stilbenes and Hypoxia

Heterotopic ossification (HO) is associated with inflammation. The goal of this review is to examine recent findings on the roles of inflammation and the immune system in HO. We examine how inflammation changes in fibrodysplasia ossificans progressiva, in traumatic HO, and in other clinical conditions of HO. We also discuss how inflammation may be a target for treating HO.. Both genetic and acquired forms of HO show similarities in their inflammatory cell types and signaling pathways. These include macrophages, mast cells, and adaptive immune cells, along with hypoxia signaling pathways, mesenchymal stem cell differentiation signaling pathways, vascular signaling pathways, and inflammatory cytokines. Because there are common inflammatory mediators across various types of HO, these mediators may serve as common targets for blocking HO. Future research may focus on identifying new inflammatory targets and testing combinatorial therapies based on these results.

Topics: Adaptive Immunity; Animals; Anti-Inflammatory Agents, Non-Steroidal; Arthroplasty, Replacement, Hip; Blast Injuries; Brain Injuries, Traumatic; Burns; Cell Differentiation; Cytokines; Humans; Hypoxia; Immunosuppressive Agents; Inflammation; Janus Kinase Inhibitors; Macrophages; Mast Cells; Mesenchymal Stem Cells; Myositis Ossificans; Ossification, Heterotopic; Postoperative Complications; Pyrazoles; Receptors, Retinoic Acid; Retinoic Acid Receptor gamma; Signal Transduction; Sirolimus; Spinal Cord Injuries; Stilbenes; Wounds and Injuries

Resveratrol, as a natural polyphenolic compound, has a wide range of beneficial effects, which includes anti-tumor, cardiovascular protection, anti-oxidant and estrogen-like effects, and so on. Its various physiological properties are closely related to the therapeutic principle for prevention and treatment of high altitude hypoxia injury. Resveratrol may play an important role in relieving or curing high altitude diseases, especially high altitude polycythemia(HAPC). However, the literature about study and application of resveratrol in plateau medicine field is rarely reported up to now. In this review, we summarized the physiological effects of resveratrol, discussed the possible main principle of resveratrol for HAPC therapy, and looked forward to resveratrol's perspective or potential application in high altitude medicine.

Topics: Altitude; Humans; Hypoxia; Polycythemia; Resveratrol; Stilbenes

Vascular targeting agents (VTAs) for the treatment of cancer are designed to cause a rapid and selective shutdown of the blood vessels of tumors. Unlike antiangiogenic drugs that inhibit the formation of new vessels, VTAs occlude the pre-existing blood vessels of tumors to cause tumor cell death from ischemia and extensive hemorrhagic necrosis. Tumor selectivity is conferred by differences in the pathophysiology of tumor versus normal tissue vessels (e.g., increased proliferation and fragility, and up-regulated proteins). VTAs can kill indirectly the tumor cells that are resistant to conventional antiproliferative cancer therapies, i.e., cells in areas distant from blood vessels where drug penetration is poor, and hypoxia can lead to radiation and drug resistance. VTAs are expected to show the greatest therapeutic benefit as part of combined modality regimens. Preclinical studies have shown VTA-induced enhancement of the effects of conventional chemotherapeutic agents, radiation, hyperthermia, radioimmunotherapy, and antiangiogenic agents. There are broadly two types of VTAs, small molecules and ligand-based, which are grouped together, because they both cause acute vascular shutdown in tumors leading to massive necrosis. The small molecules include the microtubulin destabilizing drugs, combretastatin A-4 disodium phosphate, ZD6126, AVE8062, and Oxi 4503, and the flavonoid, DMXAA. Ligand-based VTAs use antibodies, peptides, or growth factors that bind selectively to tumor versus normal vessels to target tumors with agents that occlude blood vessels. The ligand-based VTAs include fusion proteins (e.g., vascular endothelial growth factor linked to the plant toxin gelonin), immunotoxins (e.g., monoclonal antibodies to endoglin conjugated to ricin A), antibodies linked to cytokines, liposomally encapsulated drugs, and gene therapy approaches. Combretastatin A-4 disodium phosphate, ZD6126, AVE8062, and DMXAA are undergoing clinical evaluation. Phase I monotherapy studies have shown that the agents are tolerated with some demonstration of single agent efficacy. Because efficacy is expected when the agents are used with conventional chemotherapeutic drugs or radiation, the results of Phase II combination studies are eagerly awaited.

Topics: Angiogenesis Inhibitors; Antibodies, Monoclonal; Cell Division; Clinical Trials as Topic; Diphosphates; Genetic Therapy; Humans; Hypoxia; Immunotoxins; Ligands; Models, Biological; Necrosis; Neoplasms; Organophosphorus Compounds; Peptides; Radioimmunotherapy; Stilbenes; Time Factors; Up-Regulation; Xanthones

The impact of maternal nutrition on neurodevelopment and neonatal neuroprotection is a research topic with increasing interest. Maternal diet can also have deleterious effects on fetal brain development. Fetal exposure to alcohol is responsible for poor neonatal global development, and may increase brain vulnerability to hypoxic-ischemic encephalopathy, one of the major causes of acute mortality and chronic neurological disability in newborns. Despite frequent prevention campaigns, about 10% of women in the general population drinks alcohol during pregnancy and breastfeeding. This study was inspired by this alarming fact. Its aim was to evaluate the beneficial effects of maternal supplementation with two polyphenols during pregnancy and breastfeeding, on hypoxic-ischemic neonate rat brain damages, sensorimotor and cognitive impairments, in a context of moderate maternal alcoholism. Both stilbenoid polyphenols, trans-resveratrol (RSV - 0.15 mg/kg/day), and its hydroxylated analog, trans-piceatannol (PIC - 0.15 mg/kg/day), were administered in the drinking water, containing or not alcohol (0.5 g/kg/day). In a 7-day post-natal rat model of hypoxia-ischemia (HI), our data showed that moderate maternal alcoholism does not increase brain lesion volumes measured by MRI but leads to higher motor impairments. RSV supplementation could not reverse the deleterious effects of HI coupled with maternal alcoholism. However, PIC supplementation led to a recovery of all sensorimotor and cognitive functions. This neuroprotection was obtained with a dose of PIC corresponding to the consumption of a single passion fruit per day for a pregnant woman.

Topics: Alcohol Drinking; Alcoholism; Animals; Animals, Newborn; Brain; Brain Injuries; Cognitive Dysfunction; Female; Hypoxia; Hypoxia-Ischemia, Brain; Ischemia; Male; Maternal Nutritional Physiological Phenomena; Maternal-Fetal Exchange; Neuroprotection; Neuroprotective Agents; Polyphenols; Pregnancy; Prenatal Exposure Delayed Effects; Rats; Rats, Wistar; Resveratrol; Stilbenes

Combretastatin A-4 phosphate (CA4P) is a microtubule-disrupting tumour-selective vascular disrupting agent (VDA). CA4P activates the actin-regulating RhoA-GTPase/ ROCK pathway, which is required for full vascular disruption. While hypoxia renders tumours resistant to many conventional therapies, little is known about its influence on VDA activity. Here, we found that active RhoA and ROCK effector phospho-myosin light chain (pMLC) were downregulated in endothelial cells by severe hypoxia. CA4P failed to activate RhoA/ROCK/pMLC but its activity was restored upon reoxygenation. Hypoxia also inhibited CA4P-mediated actinomyosin contractility, VE-cadherin junction disruption and permeability rise. Glucose withdrawal downregulated pMLC, and coupled with hypoxia, reduced pMLC faster and more profoundly than hypoxia alone. Concurrent inhibition of glycolysis (2-deoxy-D-glucose, 2DG) and mitochondrial respiration (rotenone) caused profound actin filament loss, blocked RhoA/ROCK signalling and rendered microtubules  CA4P-resistant. Withdrawal of the metabolism inhibitors restored the cytoskeleton and CA4P activity. The AMP-activated kinase AMPK was investigated as a potential mediator of pMLC downregulation. Pharmacological AMPK activators that generate AMP, unlike allosteric activators, downregulated pMLC but only when combined with 2DG and/or rotenone. Altogether, our results suggest that Rho/ROCK and actinomyosin contractility are regulated by AMP/ATP levels independently of AMPK, and point to hypoxia/energy depletion as potential modifiers of CA4P response.

Topics: Actins; Antineoplastic Agents, Phytogenic; Cell Membrane Permeability; Endothelium, Vascular; Human Umbilical Vein Endothelial Cells; Humans; Hypoxia; Neovascularization, Pathologic; rho-Associated Kinases; rhoA GTP-Binding Protein; Signal Transduction; Stilbenes

Vascular disrupting agents (VDAs) are emerging anticancer agents, which show rising demand for combination with cytostatic drugs (CSDs), owing to inadequate tumor inhibition when applied singly. Nevertheless, the combination remains a challenge due to the different working sites of VDAs and CSDs and hypoxia-induced drug resistance after disrupting neovasculature by VDAs. Herein, we developed a shell-stacked nanoparticle (SNP) for coencapsulation of a VDA combretastatin A-4 phosphate (CA4P) and a proteasome inhibitor bortezomib (BTZ). The SNP could spatiotemporally deliver CA4P to tumor neovasculature and BTZ to tumor cells mediated by the site-specific stimuli-activated drug release. Moreover, the SNP also reversed the drug resistance caused by the overexpressed ABCG2 under CA4P-induced hypoxic conditions. The spatiotemporally targeted combination therapy significantly inhibited the growth of both the human A549 pulmonary adenocarcinoma xenograft model and patient-derived xenograft (PDX) model of colon cancer in mice, providing a promising strategy for treating advanced cancers.

Topics: Animals; Antineoplastic Agents; Drug Resistance; Hypoxia; Mice; Nanomedicine; Stilbenes

Hypoxia-ischemia (HI) remains a major cause of perinatal mortality and chronic disability in newborns worldwide (1-6 for 1000 births) with a high risk of future motor, behavioral and neurological deficits. Keeping newborns under moderate hypothermia is the unique therapeutic approach but is not sufficiently successful as nearly 50% of infants do not respond to it. In a 7-day post-natal rat model of HI, we used pregnant and breastfeeding female nutritional supplementation with piceatannol (PIC), a polyphenol naturally found in berries, grapes and passion fruit, as a neuroprotective strategy. Maternal supplementation led to neuroprotection against neonate brain damage and reversed their sensorimotor deficits as well as cognitive impairments. Neuroprotection of per os maternal supplementation with PIC is a preventive strategy to counteract brain damage in pups induced by HI. This nutritional approach could easily be adopted as a preventive strategy in humans.

Topics: Animals; Animals, Newborn; Behavior, Animal; Brain; Brain Injuries; Cognitive Dysfunction; Dietary Supplements; Disease Models, Animal; Female; Hypoxia; Hypoxia-Ischemia, Brain; Ischemia; Maternal Nutritional Physiological Phenomena; Neurons; Neuroprotection; Neuroprotective Agents; Pregnancy; Rats; Stilbenes

Stilbenes with well-known antioxidant and antiradical properties are beneficial in different pathologies including cardiovascular diseases. The present research was performed to investigate the potential protective effect of resveratrol (1) and piceatannol (2), against hypoxia-induced oxidative stress in the H9c2 cardiomyoblast cell line, and the underlying mechanisms. Compounds 1 and 2 significantly inhibited the release of peroxynitrite and thiobarbituric acid levels at na no- or submicromolar concentrations, and this effect was more evident in piceatannol-treated cells, that significantly increased MnSOD protein level in a concentration dependent manner. Furthermore, since piceatannol, which is far less abundant in natural sources, displayed a higher bioactivity than the parent compound, we hereby report on a very fast synthesis and detailed structure-based design of a focused stilbene library. Finally, taking into account that hypoxia-induced ROS accumulation also increases expression and activity of 5-lipoxygenase (5-LOX) with production of leukotrienes, we have disclosed structural key factors crucial for 5-LOX activity. Among the synthesized analogues ( 3-7), compound 7 was the most effective in improving cardiomyocytes viability and in 5-LOX inhibition. In conclusion, modeling and experimental studies provided the basis for further optimization of stilbene analogues as multi-target inhibitors of the inflammatory and oxidative pathway.

Topics: Animals; Arachidonate 5-Lipoxygenase; Cell Proliferation; Cells, Cultured; Dose-Response Relationship, Drug; Hypoxia; Lipoxygenase Inhibitors; Molecular Structure; Myocytes, Cardiac; Protective Agents; Rats; Stilbenes; Structure-Activity Relationship

Resveratrol has been demonstrated to have cardioprotective effects by attenuating ischemia/reperfusion (I/R)-induced oxidative stress injury, but its in-depth molecular mechanisms against I/R-induced oxidative stress is not fully elaborated. DJ-1 plays a role in maintenance of mitochondrial complex I activity and is closely associated with oxidative stress. Therefore, this study sought to determine the contribution of DJ-1-mediated maintenance of mitochondrial complex I activity to the anti-oxidative stress effect of Resveratrol in the H9c2 cardiomyocytes subjected to hypoxia/reoxygenation (H/R). The results showed that Resveratrol significantly attenuated the H/R-induced viability loss and lactate dehydrogenase leakage, accompanied by decreases in intracellular reactive oxygen species (ROS) and malondialdehyde contents and increases in the reduced glutathione/oxidized glutathione ratio. Furthermore, Resveratrol increased the expression and mitochondrial translocation of DJ-1 and promoted the direct binding of DJ-1 with complex I subunits ND1 and NDUFS4, which in turn improved mitochondrial complex I activity and inhibited mitochondria-derived ROS production after H/R. Intriguingly, the anti-oxidative stress effect of Resveratrol could be partially blocked by DJ-1 siRNA and Complex I inhibitor Rotenone, respectively. Conclusively, these results indicated that DJ-1 is necessary for Resveratrol-mediated cardioprotective effects against H/R-induced oxidative stress damage, at least in part, through preserving mitochondrial complex I activity, and subsequently decreasing mitochondrial ROS generation.

Topics: Animals; Cardiotonic Agents; Cell Line; Electron Transport Complex I; Hypoxia; L-Lactate Dehydrogenase; Mitochondria; Myocytes, Cardiac; Oxidative Stress; Protein Deglycase DJ-1; Rats; Reactive Oxygen Species; Reperfusion Injury; Resveratrol; RNA, Small Interfering; Stilbenes

Although recent studies have reported that mitochondria are putative oxygen sensors underlying hypoxic pulmonary vasoconstriction, little is known concerning the sirtuin 1 (SIRT1)-mediated mitochondrial biogenesis regulatory program in pulmonary arteriolar smooth muscle cells (PASMCs) during hypoxia/reoxygenation (H/R). We investigated the epigenetic regulatory mechanism of mitochondrial biogenesis and function in human PASMCs during H/R. Human PASMCs were exposed to hypoxia of 24-48 h and reoxygenation of 24-48 h. The expression of SIRT1 was reduced in a time-dependent manner. Mitochondrial transcription factor A (TFAM) expression was increased during hypoxia and decreased during reoxygenation, while the release of TFAM was increased in a time-dependent manner. Lentiviral overexpression of SIRT1 preserved SIRT3 deacetylase activity in human PASMCs exposed to H/R. Knockdown of PGC-1α suppressed the effect of SIRT1 on SIRT3 activity. Knockdown of SIRT3 abrogated SIRT1-mediated deacetylation of cyclophilin D (CyPD). Notably, knockdown of SIRT3 or PGC-1α suppressed the incremental effect of SIRT1 on mitochondrial TFAM, mitochondrial DNA (mtDNA) content and cellular ATP levels. Importantly, polydatin restored SIRT1 levels in human PASMCs exposed to H/R. Knockdown of SIRT1 suppressed the effect of polydatin on mitochondrial TFAM, mtDNA content and cellular ATP levels. In conclusion, SIRT1 expression is decreased in human PASMCs during H/R. TFAM expression in mitochondria is reduced and the release of TFAM is increased by H/R. PGC-1α/SIRT3/CyPD mediates the protective effect of SIRT1 on expression and release of TFAM and mitochondrial biogenesis and function. Polydatin improves mitochondrial biogenesis and function by enhancing SIRT1 expression in hypoxic human PASMCs.

Topics: Biomarkers; DNA-Binding Proteins; Gene Expression; Gene Knockdown Techniques; Glucosides; Humans; Hypoxia; Mitochondria, Muscle; Mitochondrial Proteins; Models, Biological; Myocytes, Smooth Muscle; Organelle Biogenesis; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; Pulmonary Artery; Sirtuin 1; Sirtuin 3; Stilbenes; Transcription Factors

Topics: Antineoplastic Agents, Phytogenic; Dose-Response Relationship, Drug; Gene Expression Regulation, Neoplastic; Hep G2 Cells; Hepatocytes; Humans; Hypoxia; Hypoxia-Inducible Factor 1, alpha Subunit; Neoplasms; Oxygen; Plasminogen Activator Inhibitor 1; Polyphenols; Resveratrol; RNA, Messenger; Stilbenes

Long-term intermittent hypoxia (IH) is a characteristic hallmark of obstructive sleep apnea (OSA) and causes most of the neurological aspects of OSA, such as spatial memory and learning deficits. These deficits are accompanied by an increase in oxidative stress and inflammation in brain areas involved in cognition, such as the hippocampus, particularly in children. Resveratrol is a natural polyphenolic compound with potent antioxidant, anti-inflammatory and neuroprotective properties.. The aim of this work is to study the possible protective effect of resveratrol against IH-induced neurobehavioral deficits and to investigate the possible mechanism of this protective effect in the young rat model of OSA.. The effect of resveratrol (5 and 10mg/kg, orally) on anxiety, spatial memory and learning deficits in young rats exposed to IH for 6 weeks and the corresponding biochemical changes were studied.. Resveratrol attenuated IH-induced anxiety and spatial memory deficits, as indicated by the elevated plus maze and Morris water maze tests, respectively, in a dose-dependent manner. In addition, resveratrol antagonized IH-induced increases in hippocampal glutamate, TBARS and 8-OHdG levels and p47Phox expression and decreases in GSH levels and GSH-Px activity in the hippocampus of IH-exposed young rats.. Resveratrol ameliorates IH-induced anxiety and spatial learning deficits through multiple beneficial effects on hippocampal oxidative pathways that involve decreased expression of the p47Phox subunit of NADPH oxidase. Hence, the potential therapeutic role of resveratrol in OSA may be utilized in the near future and deserves further exploration.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Animals; Deoxyguanosine; Disease Models, Animal; DNA Damage; Dose-Response Relationship, Drug; Glutamic Acid; Glutathione; Glutathione Reductase; Hemoglobins; Hippocampus; Hypoxia; Male; Maze Learning; Memory Disorders; NADPH Oxidases; Neuroprotective Agents; Rats; Rats, Wistar; Reaction Time; Resveratrol; Stilbenes; Thiobarbituric Acid Reactive Substances

Hypoxic activation of hypoxia-inducible factor 1α (HIF-1α) and fibrosis in adipose tissue contribute to adipose dysfunction. This study was designed to investigate the effects of metformin and resveratrol on the regulation of HIF-1α and fibrosis in hypoxic adipose tissue.. Mice were fed a high-fat diet to induce hypoxia and fibrosis in adipose tissue; adipose tissue incubated in vitro in 1% O2 showed a similar change. The effects of metformin and resveratrol on hypoxia, HIF-1α accumulation, endoplasmic reticulum stress and gene expressions of extracellular matrix components and pro-inflammatory cytokines were examined.. Oral administration of metformin or resveratrol prevented hypoxia and reduced HIF-1α accumulation with dephosphorylation of inositol-requiring enzyme 1α and eukaryotic initiation factor 2α, indicative of suppression of hypoxic HIF-1α activation and endoplasmic reticulum stress. Metformin and resveratrol down-regulated gene expressions of Col3α, Col6α, elastin and lysyl oxidase and thereby reduced collagen deposition in adipose tissue. The increased gene expressions of TNF-α, IL-6, monocyte chemoattractant protein 1 and F4/80 were also down-regulated by metformin and resveratrol. Metformin and resveratrol had similar effects in adipose tissue exposed to 1% O2 . Metformin reduced ATP production and prevented the reduction in oxygen tension in 3T3-L1 cells, suggesting that it prevented hypoxia by limiting oxygen consumption, whereas resveratrol reduced HIF-1α accumulation by promoting its proteasomal degradation via the regulation of AMPK/SIRT1.. Hypoxia and fibrosis are early causes of adipose dysfunction in obesity. Both metformin and resveratrol effectively inhibited HIF-1α activation-induced fibrosis and inflammation in adipose tissue, although by different mechanisms.

Topics: 3T3-L1 Cells; Adipose Tissue; Animals; Cells, Cultured; Dose-Response Relationship, Drug; Fibrosis; Hypoxia; Hypoxia-Inducible Factor 1, alpha Subunit; Inflammation; Male; Metformin; Mice; Mice, Inbred ICR; Resveratrol; Stilbenes; Structure-Activity Relationship

To investigate the polarization effect of Malibatol A on oxygen-glucose deprivation (OGD)-BV-2 cells, and the possible molecular mechanism involved in c-Abl-MST signaling pathway.. The OGD BV-2 cell model was established. BV-2 cells were exposed to OGD for 8 h followed by reperfusion for 15 h with Malibatol A at different concentration of 0.5, 1, 2, 4, 8, 16 μM or without it. And then cells, mRNA and protein were harvested respectively. The cell viability and apoptosis were measured by MTT assay and flow cytometry. The mRNA of classical activated microglia (M1) markers (MCP-1, IL-1 and TNF-α) and alternatively activated microglia (M2) markers (Ym-1, CD206, IL-10, TGF-β) in BV-2 cells were measured by RT-PCR. Meanwhile, the proteins of Ym-1 and CD206 was assayed by flow cytometry. Furthermore, the expression of c-Abl and MST was measured by Western blot.. Malibatol A significantly decreased apoptosis and increased viability of OGD BV-2 cells in a dose-dependent manner. In the presence of Malibatol A, the mRNA levels of Ym-1, CD206, IL-10 and TGF-β mRNA was significantly increased in OGD-BV-2 cells, while the mRNA levels of MCP-1, IL-1 and TNF-α was obviously down-regulated. Meanwhile, the proteins of Ym-1 and CD206 was raised in OGD BV-2 cells with Malibatol A. Besides, Malibatol A also inhibited OGD-induced p-MST1(Y433) in BV-2 cells.. Malibatol A could attenuate OGD-induced BV-2 cell injury and promote M2 microglia polarization. The mechanism may be related to inhibition of MST1 phosphorylation at Y433.

Topics: Animals; Apoptosis; Cell Line, Transformed; Dose-Response Relationship, Drug; Doxorubicin; Flow Cytometry; Gene Expression Regulation; Glucose; Hypoxia; Lectins, C-Type; Mannose Receptor; Mannose-Binding Lectins; Mice; Microglia; Phosphorylation; Protein Serine-Threonine Kinases; Receptors, Cell Surface; RNA, Messenger; Signal Transduction; Stilbenes

This study aims to investigate the effects of metformin and resveratrol on muscle insulin resistance with emphasis on the regulation of lipolysis in hypoxic adipose tissue. ICR mice were fed with high fat diet (HFD) for 10days with administration of metformin, resveratrol, or intraperitoneal injection of digoxin. Adipose hypoxia, inflammation and cAMP/PKA-dependent lipolysis were investigated. Moreover, lipid deposition and insulin resistance were examined in the muscle. Metformin and resveratrol attenuated adipose hypoxia, inhibited HIF-1α expression and inflammation in the adipose tissue of HFD-fed mice. Metformin and resveratrol inhibited lipolysis through prevention of PKA/HSL activation by decreasing the accumulation of cAMP via preserving PDE3B. Metformin and resveratrol reduced FFAs influx and DAG accumulation, and thus improved insulin signaling in the muscle by inhibiting PKCθ translocation. This study presents a new view of regulating lipid metabolism to ameliorate insulin resistance and provides the clinical guiding significance for obesity and type 2 diabetes with metformin and resveratrol treatment.

Topics: 3T3-L1 Cells; Adipose Tissue; Administration, Oral; Animals; Cyclic AMP; Cyclic AMP-Dependent Protein Kinases; Diet, High-Fat; Diglycerides; Fatty Acids; Feeding Behavior; Glucose; Hypoxia; Inflammation; Insulin; Insulin Resistance; Lipolysis; Male; Metformin; Mice; Mice, Inbred ICR; Models, Biological; Muscles; Resveratrol; Signal Transduction; Stilbenes

Tumor hypoxia is associated with treatment resistance, cell proliferation, and metastatic potential, all of which contribute to a poor prognosis. Resveratrol [RES (trans-3,4',5-trihydroxystilbene)], a naturally occurring polyphenol, is enriched in grapes and red wine. This study investigated whether the resveratrol analog HS-1793 modulates the hypoxic status and the level of perfusion in mouse breast cancer FM3A cells. Our data show that HS-1793 decreased the levels of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor protein under hypoxic conditions in FM3A cells. HS-1793 improved perfusion and hypoxic status in tumor tissues and inhibited angiogenesis through HIF-1α suppression in mice. Moreover, HS-1793 inhibited hypoxia-induced cancer stem cell properties and enhanced ionizing radiation-induced apoptosis in hypoxic FM3A cells. Collectively, the resveratrol analog HS-1793 might act as a potent radiosensitizer and be a useful adjuvant agent against radiotherapy-resistant hypoxic cells in solid tumors.

Topics: Animals; Antineoplastic Agents, Phytogenic; Blotting, Western; Cell Movement; Cell Survival; Enzyme-Linked Immunosorbent Assay; Female; Hypoxia; Mammary Neoplasms, Experimental; Mice; Mice, Inbred C3H; Microscopy, Fluorescence; Naphthols; Neoplastic Stem Cells; Neovascularization, Pathologic; Radiation Tolerance; Radiation-Sensitizing Agents; Real-Time Polymerase Chain Reaction; Resorcinols; Resveratrol; Stilbenes; Tumor Cells, Cultured

Topics: Animals; Antioxidants; Hypertension, Pulmonary; Hypoxia; Hypoxia-Inducible Factor 1, alpha Subunit; Inflammation; NF-E2-Related Factor 2; Random Allocation; Rats; Reactive Oxygen Species; Resveratrol; Stilbenes; Thioredoxins

Polyphenols possess antioxidant and anti-inflammatory properties. Oxidative stress (OS) and inflammation have been implicated in the pathogenesis of cytotoxic brain edema in cerebral ischemia. In addition, OS and pro-inflammatory cytokines also damage the endothelial cells and the neurovascular unit. Endothelial cell swelling may contribute to a leaky blood-brain barrier which may result in vasogenic edema in the continued presence of the existing cytotoxic edema. We investigated the protective effects of polyphenols on cytotoxic cell swelling in bEND3 endothelial cultures subjected to 5 hours oxygen-glucose deprivation (OGD). A polyphenol trimer from cinnamon (cinnamtannin D1), a polyphenol-rich extract from green tea, and resveratrol prevented the OGD-induced rise in mitochondrial free radicals, cell swelling, and the dissipation of the inner mitochondrial membrane potential. Monocyte chemoattractant protein (also called CCL2), a chemokine, but not tumor necrosis factor-α or interleukin-6, augmented the cell swelling. This effect of monochemoattractant protein 1-1 was attenuated by the polyphenols. Cyclosporin A, a blocker of the mitochondrial permeability transition pore, did not attenuate cell swelling but BAPTA-AM, an intracellular calcium chelator did, indicating a role of [Ca(2+)]i but not the mPT in cell swelling. These results indicate that the polyphenols reduce mitochondrial reactive oxygen species and subsequent cell swelling in endothelial cells following ischemic injury and thus may reduce brain edema and associated neural damage in ischemia. One possible mechanism by which the polyphenols may attenuate endothelial cell swelling is through the reduction in [Ca(2+)]i.

Topics: Animals; Antioxidants; Brain Ischemia; Calcium; Cell Line; Chemokine CCL2; Cyclosporine; Egtazic Acid; Endothelial Cells; Glucose; Hypoxia; Interleukin-6; Membrane Potential, Mitochondrial; Mice; Mitochondria; Mitochondrial Membrane Transport Proteins; Mitochondrial Permeability Transition Pore; Oxidative Stress; Plant Extracts; Polyphenols; Proanthocyanidins; Reactive Oxygen Species; Resveratrol; Stilbenes; Tea; Tumor Necrosis Factor-alpha

Obstructive sleep apnea can induce chronic intermittent hypoxia (CIH) during sleep and is associated with obesity and diabetes. Resveratrol (RSV), a polyphenolic phytoalexin, can regulate glucose metabolism, thereby reducing insulin resistance. The present study aimed to assess whether RSV attenuates CIH-induced insulin resistance in rats and the underlying mechanisms. A total of 40 rats were randomly assigned into five groups: i) Control; ii) subjected to CIH only; iii) subjected to CIH and treated with 3 mg/kg/day of RSV; iv) subjected to CIH and treated with 30 mg/kg/day of RSV; v) subjected to CIH and treated with 60 mg/kg/day of RSV. All animals were sacrificed following 28 days of treatment. Subsequently, the blood and livers were harvested and blood insulin and glucose levels were measured. Levels of sirtuin (Sirt) 1, insulin receptor (InsR) and glucose transporter 2 (Glut2) in the liver were measured. RSV treatment was demonstrated to suppress weight gain and improve hepatic morphology. RSV treatment also significantly reduced the homeostasis model assessment estimate of insulin resistance of the rats exposed to CIH. This effect occurred in a dose-dependent manner. RSV significantly upregulated liver Sirt1 levels and inhibited InsR and Glut2 expression in the liver. Additionally, RSV activated the phosphorylation of phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) and AKT. The present study demonstrates that RSV prevents CIH-induced insulin resistance in rats. Upregulation of Sirt1 and activation of PI3K/AKT signaling may be involved in this process.

Topics: Animals; Blood Glucose; Body Weight; Gene Expression Regulation; Glucose Transporter Type 2; Hypoxia; Insulin; Insulin Resistance; Liver; Male; Phosphatidylinositol 3-Kinases; Phosphorylation; Protective Agents; Proto-Oncogene Proteins c-akt; Rats; Receptor, Insulin; Resveratrol; RNA, Messenger; Signal Transduction; Sirtuin 1; Stilbenes

Chronic intermittent hypoxia during sleep (IH), as occurs in sleep apnea, promotes systemic insulin resistance. Resveratrol (Resv) has been reported to ameliorate high-fat diet-induced obesity, inflammation, and insulin resistance. To examine the effect of Resv on IH-induced metabolic dysfunction, male mice were subjected to IH or room air conditions for 8 weeks and treated with either Resv or vehicle (Veh). Fasting plasma levels of glucose, insulin, and leptin were obtained, homeostatic model assessment of insulin resistance index levels were calculated, and insulin sensitivity tests (phosphorylated AKT [also known as protein kinase B]/total AKT) were performed in 2 visceral white adipose tissue (VWAT) depots (epididymal [Epi] and mesenteric [Mes]) along with flow cytometry assessments for VWAT macrophages and phenotypes (M1 and M2). IH-Veh and IH-Resv mice showed initial reductions in food intake with later recovery, with resultant lower body weights after 8 weeks but with IH-Resv showing better increases in body weight vs IH-Veh. IH-Veh and IH-Resv mice exhibited lower fasting glucose levels, but only IH-Veh had increased homeostatic model assessment of insulin resistance index vs all 3 other groups. Leptin levels were preserved in IH-Veh but were significantly lower in IH-Resv. Reduced VWAT phosphorylated-AKT/AKT responses to insulin emerged in both Mes and Epi in IH-Veh but normalized in IH-Resv. Increases total macrophage counts and in M1 to M2 ratios occurred in IH-Veh Mes and Epi compared all other 3 groups. Thus, Resv ameliorates food intake and weight gain during IH exposures and markedly attenuates VWAT inflammation and insulin resistance, thereby providing a potentially useful adjunctive therapy for metabolic morbidity in the context of sleep apnea.

Topics: Animals; Anti-Obesity Agents; Drug Evaluation, Preclinical; Eating; Hypoxia; Insulin; Insulin Resistance; Intra-Abdominal Fat; Leptin; Macrophages; Male; Mice, Inbred C57BL; Random Allocation; Resveratrol; Stilbenes; Weight Gain

Ineffective mucociliary clearance (MCC) is a common pathophysiologic process that underlies airway inflammation and infection. A dominant fluid and electrolyte secretory pathway in the nasal airways is governed by the cystic fibrosis transmembrane conductance regulator (CFTR). Decreased transepithelial Cl(-) transport secondary to an acquired CFTR deficiency may exacerbate respiratory epithelial dysfunction by diminishing MCC and increasing mucus viscosity. The objectives of the present study are to 1) develop a model of acquired CFTR deficiency in sinonasal epithelium using hypoxia, 2) investigate whether the polyphenol resveratrol promotes CFTR-mediated anion transport, 3) explore resveratrol mechanism of action and determine therapeutic suitability for overcoming acquired CFTR defects, and 4) test the drug in the hypoxic model of acquired CFTR deficiency in preparation for a clinical trial in human sinus disease. We hypothesize that hypoxia will induce depletion of airway surface liquid (ASL) secondary to acquired CFTR deficiency and that resveratrol will restore transepithelial Cl(-) secretion and recover ASL hydration.. Basic science.. Murine nasal septal (MNSE) and human sinonasal epithelial (HSNE) cultures were incubated under hypoxic conditions (1% O2 , 5% CO2 ) and transepithelial ion transport (change in short-circuit current = ΔISC ) evaluated in Ussing chambers. Resveratrol was tested using primary cells and HEK293 cells expressing human CFTR by Ussing chamber and patch clamp techniques under both phosphorylating and nonphosphorylating conditions. CFTR activation was evaluated in human explants and by murine in vivo (nasal potential difference) assessment. Cellular cyclic adenosine monophosphate (cAMP) (ELISA) and subsequent CFTR regulatory domain (R-D) phosphorylation (gel-shift assay) were also evaluated. Effects of hypoxia and resveratrol on ASL were tested using confocal laser scanning microscopy (CLSM) and micro-optical coherence tomography (µOCT).. Hypoxia significantly decreased ΔISC (in µA/cm(2) ) attributable to CFTR at 12 and 24 hours of exposure in both MNSE (13.55 ± 0.46 [12 hours]; 12.75 ± 0.07 [24 hours] vs. 19.23 ± 0.18 [control]; P < 0.05) and HSNE (19.55 ± 0.56 [12 hours]; 17.67 ± 1.13 [24 hours] vs. 25.49 ± 1.48 [control]; P < 0.05). We have shown that resveratrol (100 μM) enhanced CFTR-dependent Cl(-) secretion in HSNE to an extent comparable to the recently Food and Drug Administration-approved CFTR potentiator, ivacaftor. Cl(-) transport across human sinonasal explants (78.42 ± 1.75 vs. 1.75 ± 1.5 [control]; P < 0.05) and in vivo murine nasal epithelium (-4 ± 1.8 vs. -0.8 ± 1.7 mV [control]; P < 0.05) were also significantly increased by the drug. No increase in cAMP or CFTR R-D phosphorylation was detected. Inside-out patches showed increased CFTR open probability (NPo/N (N = channel number]) compared to controls in both MNSE (0.329 ± 0.116 vs. 0.119 ± 0.059 [control]; P < 0.05) and HEK293 cells (0.22 ± 0.048 vs. 0.125 ± 0.07 [control]; P < 0.05). ASL thickness was decreased under hypoxic conditions when measured by CLSM (4.19 ± 0.44 vs. 6.88 ± 0.67 [control]; P < 0.05). A 30-minute apical application of resveratrol increased ASL depth in normal epithelium (8.08 ± 1.68 vs. 6.11 ± 0.47 [control]; P < 0.05). Furthermore, hypoxia-induced abnormalities of fluid and electrolyte secretion in sinonasal epithelium were restored with resveratrol treatment (5.55 ± 0.74 vs. 3.13 ± 0.17 [control]; P < 0.05).. CFTR activation with a leading edge Cl(-) secretagogue such as resveratrol represents an innovative approach to overcoming acquired CFTR defects in sinus and nasal airway disease. This exciting new strategy bears further testing in non-CF individuals with chronic rhinosinusitis.. N/A. Laryngoscope, 125:S1-S13, 2015.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Biological Transport, Active; Cells, Cultured; Chloride Channels; Cyclic AMP; Cystic Fibrosis Transmembrane Conductance Regulator; Epithelial Cells; HEK293 Cells; Humans; Hypoxia; Ion Transport; Mice; Mice, Inbred C57BL; Microscopy, Confocal; Models, Biological; Mucociliary Clearance; Nasal Mucosa; Paranasal Sinuses; Patch-Clamp Techniques; Phosphorylation; Resveratrol; Stilbenes; Swine

Resveratrol is a natural polyphenol enriched in Polygonum cuspidatum and has been found to afford neuroprotective effects against neuroinflammation in the brain. Activated microglia can secrete various pro-inflammatory cytokines and neurotoxic mediators, which may contribute to hypoxic brain injuries. The aim of this study is to investigate the potential role of resveratrol in attenuating hypoxia-induced neurotoxicity via its anti-inflammatory actions through in vitro models of the BV-2 microglial cell line and primary microglia. We found that resveratrol significantly inhibited hypoxia-induced microglial activation and reduced subsequent release of pro-inflammatory factors. In addition, resveratrol inhibited the hypoxia-induced degradation of IκB-alpha and phosphorylation of p65 NF-κB protein. Hypoxia-induced ERK1/2 and JNK phosphorylation was also strongly inhibited by resveratrol, whereas resveratrol had no effect on hypoxia-stimulated p38 MAPK phosphorylation. Importantly, treating primary cortical neurons with conditioned medium (CM) from hypoxia-stimulated microglia induced neuronal apoptosis, which was reversed by CM co-treated with resveratrol. Taken together, resveratrol exerts neuroprotection against hypoxia-induced neurotoxicity through its anti-inflammatory effects in microglia. These effects were mediated, at least in part, by suppressing the activation of NF-ĸB, ERK and JNK MAPK signaling pathways.

Topics: Animals; Cell Line; Cells, Cultured; Hypoxia; Interleukin-1beta; Mice; Microglia; Mitogen-Activated Protein Kinases; Neuroprotective Agents; NF-kappa B; Nitric Oxide; Resveratrol; Stilbenes; Tumor Necrosis Factor-alpha

To investigate the effects of resveratrol on the expression of hypoxia-inducible factor 1α (HIF-1α) and vascular endothelial growth factor (VEGF) in human adult retinal pigment epithelial (ARPE-19) cells, and on experimental choroidal neovascularization (CNV) in mice.. ARPE-19 cells were treated with different concentrations of resveratrol and then incubated under hypoxic conditions with subsequent evaluation of cell viability, expression of HIF-1α, and expression of VEGF. The effects of resveratrol on the synthesis and degradation of hypoxia-induced HIF-1α were evaluated using inhibitors of the PI3K/Akt/mTOR and the ubiquitin proteasome pathways. In animal studies, CNV lesions were induced in C57BL/6 mice by laser photocoagulation. After 7 days of oral administration of resveratrol or vehicle, which began one day after CNV induction, image analysis was used to measure CNV areas on choroidal flat mounts stained with isolectin IB4.. In ARPE-19 cells, resveratrol significantly inhibited HIF-1α and VEGF in a dose-dependent manner, by blocking the PI3K/Akt/mTOR signaling pathway and by promoting proteasomal HIF-1α degradation. In mice experiments, orally administered resveratrol significantly inhibited CNV growth in a dose-dependent manner.. Resveratrol may have therapeutic value in the management of diseases involving pathological neovascularization.

Topics: Adult; Animals; Cell Survival; Choroidal Neovascularization; Humans; Hypoxia; Hypoxia-Inducible Factor 1, alpha Subunit; Mice; Mice, Inbred C57BL; Phosphatidylinositol 3-Kinases; Phosphoinositide-3 Kinase Inhibitors; Proteasome Endopeptidase Complex; Proto-Oncogene Proteins c-akt; Resveratrol; Retinal Pigment Epithelium; Signal Transduction; Stilbenes; TOR Serine-Threonine Kinases; Ubiquitin; Vascular Endothelial Growth Factor A

Reducing oxidative stress is crucial to prevent hypoxia-reoxygenation (H/R)-induced lung injury. Resveratrol has excellent antioxidant and anti-inflammatory effects, and this study investigated its role in H/R-induced type II pneumocyte dysfunction. H/R conditions increased expression of inflammatory cytokines including interleukin (IL)-1β (142.3 ± 21.2%, P < 0.05) and IL-6 (301.9 ± 35.1%, P < 0.01) in a type II alveolar epithelial cell line (A549), while the anti-inflammatory cytokine IL-10 (64.6 ± 9.8%, P < 0.05) and surfactant proteins (SPs) decreased. However, resveratrol treatment effectively inhibited these effects. H/R significantly activated an inflammatory transcription factor, nuclear factor (NF)-κB, while resveratrol significantly inhibited H/R-induced NF-κB transcription activities. To the best of our knowledge, this is the first study showing resveratrol-mediated reversal of H/R-induced inflammatory responses and dysfunction of type II pneumocyte cells in vitro. The effects of resveratrol were partially mediated by promoting SP expression and inhibiting inflammation with NF-κB pathway involvement. Therefore, our study provides new insights into mechanisms underlying the action of resveratrol in type II pneumocyte dysfunction.

Topics: Anti-Inflammatory Agents; Cell Line; Epithelial Cells; Humans; Hypoxia; Interleukin-1beta; Interleukin-6; Lung Injury; Oxygen; Pulmonary Alveoli; Resveratrol; Stilbenes

To explore the effects of polydatin on human kidney tubular epithelial cells (HK-2 cells) with oxygen-glucose deprivation/re-oxygenation (OGD/R)-induced injury and potential mechanisms.. HK-2 cells were cultured under normal or OGD/R condition with different drug treatment methods, including 10, 20 and 40 μmol/L polydatin, and 1 μmol/L Wortmannin, a specific phosphatidylinositol 3-kinase (PI3K) inhibitor. MTT assay was used to detect the survival ability of cells in different groups. The contents of tumor necrosis factor α (TNF-α) and interleukine 1β (IL-1β) in supernatant fluids of the cultured cells were examined by ELISA. And Western blotting was performed to determine the protein levels of total Akt (t-Akt), phospho-Akt (p-Akt) and Sonic hedgehog (Shh) in different groups.. Polydatin significantly improved the viability of cells with OGD/R treatment, and apparently inhibited the secretion of TNF-α and IL-1β induced by OGD/R. The inhibition of PI3K/Akt signaling pathway counteracted the anti-inflammation and pro-survival effects of polydatin and blocked the protein expression of Shh in HK-2 cells. The exogenous addition of human recombinant Shh protein not only improved the survival of cells with OGD/R treatment, but also inhibited the inflammation induced by OGD/R in HK-2 cells.. Polydatin can exert protective effects on HK-2 cells with OGD/R through regulating the PI3K/Akt-dependent Shh pathway.

Topics: Cell Survival; Cells, Cultured; Cytoprotection; Glucosides; Hedgehog Proteins; Humans; Hypoxia; Phosphatidylinositol 3-Kinases; Proto-Oncogene Proteins c-akt; Signal Transduction; Stilbenes

The pathogenesis of obstructive sleep apnea--hypopnea syndrome (OSAHS) is summarized as the narrow anatomic structure of upper airway (UA) and the defective function of UA dilator muscles. Up to now, there have been no specific treatments for the UA dilator muscle deficiency. We previously found that some estrogen-like compounds exert protective effects on genioglossus, but this protection tends to be less satisfactory. A novel phytoestrogen derivative was synthesized in recent years and was verified to have some cytoprotective activity. This study was designed to compare the effects of natural estrogens and the synthetic resveratrol dimer on genioglossus contraction and expression of estrogen receptors (ERs) under chronic intermittent hypoxia (CIH) condition. Genioglossus myoblasts of rat were isolated and cultured in a culture medium with different agents (estradiol, genistein, resveratrol, and resveratrol dimer, respectively) under hypoxia condition, and ERs expressions were detected. In vivo study, 48 ovariectomized female rats were randomized into six groups. After CIH exposure and agents injection, rats were tested for genioglossus contractile properties and further analysis of ERs expression. Estradiol up-regulated ERα level and exerted the best protective effect of fatigue resistance. Genistein, resveratrol and resveratrol dimer primarily up-regulated the expression of ERβ. Resveratrol dimer exhibited better protection of fatigue resistance than genistein and resveratrol, and expressed higher binding affinity for ERβ than for ERα. Besides estrogenic effects, there may be some other mechanisms for the fatigue resistance improvement contributed by phytoestrogens and their derivatives.

Topics: Animals; Cells, Cultured; Disease Models, Animal; Estradiol; Estradiol Congeners; Estrogen Receptor alpha; Estrogen Receptor beta; Estrogens; Female; Genistein; Hypoxia; Indenes; Muscle Contraction; Muscle Fatigue; Muscle, Skeletal; Myoblasts, Skeletal; Rats; Rats, Sprague-Dawley; Resorcinols; Resveratrol; Sleep Apnea, Obstructive; Stilbenes; Tongue

Recent studies show that resveratrol exerts beneficial effects on prevention of pulmonary hypertension. This study is performed to explore the effects of trimethoxystilbene, a novel resveratrol analog, on rat pulmonary vascular remodeling and right ventricular hypertrophy in hypoxia-induced pulmonary arterial hypertension (PAH) and the underlying mechanisms. Sprague-Dawley rats were placed in a chamber and exposed to 10% O(2) continuously for 4 weeks to induce PAH. The effects of trimethoxystilbene (5 or 10 mg/kg per day, intragastric [i.g.]) and resveratrol (as a positive control, 25 mg/kg per day, i.g.) on hypoxia-induced PAH vascular remodeling and right ventricle hypertrophy were evaluated. At the end of experiments, the index for pulmonary vascular remodeling and right ventricle hypertrophy, inflammatory cell infiltration in lung tissue, the plasma levels and lung tissue contents of hydrogen peroxide (H(2)O(2)), the mRNA and protein levels for NADPH oxidases (NOX2, NOX4) and vascular peroxidase 1 (VPO1) in pulmonary artery or right ventricle were measured. The results showed that trimethoxystilbene treatment significantly attenuated hypoxia-induced pulmonary vascular remodeling (such as decrease in the ratio of wall thickness to vessel external diameter) and right ventricle hypertrophy (such as decrease in the ratio of right ventricle weight to the length of the tibia), accompanied by downregulation of NOX2, NOX4, and VPO1 expression in pulmonary artery or right ventricle, decrease in H(2)O(2) production and inflammatory cell infiltration in lung tissue. Trimethoxystilbene is able to prevent pulmonary vascular remodeling and right ventricle hypertrophy in hypoxia-induced rat model of PAH, which is related to inhibition of the NOX/VPO1 pathway-mediated oxidative stress and the inflammatory reaction.

Topics: Animals; Hemeproteins; Hypertension, Pulmonary; Hypoxia; Inflammation; Male; Membrane Glycoproteins; NADPH Oxidase 2; NADPH Oxidase 4; NADPH Oxidases; Peroxidases; Random Allocation; Rats; Rats, Sprague-Dawley; Resveratrol; Signal Transduction; Stilbenes; Ventricular Remodeling

Pulmonary artery smooth muscle cell (PASMC) proliferation plays a fundamental role in the vascular remodeling seen in pulmonary hypertensive diseases associated with hypoxia. Arginase II, an enzyme regulating the first step in polyamine and proline synthesis, has been shown to play a critical role in hypoxia-induced proliferation of human PASMC (hPASMC). In addition, there is evidence that patients with pulmonary hypertension have elevated levels of arginase in the vascular wall. Resveratrol, a natural polyphenol found in red wine and grape skins, has diverse biochemical and physiological actions including antiproliferative properties. Furthermore, resveratrol has been shown to attenuate right ventricular and pulmonary artery remodeling, both pathological components of pulmonary hypertension. The present studies tested the hypothesis that resveratrol would prevent hypoxia-induced pulmonary artery smooth muscle cell proliferation by inhibiting hypoxia-induced arginase II expression. Our data indicate that hypoxia-induced hPASMC proliferation is abrogated following treatment with resveratrol. In addition, the hypoxic induction of arginase II was directly attenuated by resveratrol treatment. Furthermore, we found that the inhibitory effect of resveratrol on arginase II in hPASMC was mediated through the PI3K-Akt signaling pathway. Supporting these in vitro findings, resveratrol normalized right ventricular hypertrophy in an in vivo neonatal rat model of chronic hypoxia-induced pulmonary hypertension. These novel data support the notion that resveratrol may be a potential therapeutic agent in pulmonary hypertension by preventing PASMC arginase II induction and proliferation.

Topics: Animals; Arginase; Cell Proliferation; Cells, Cultured; Humans; Hypertension, Pulmonary; Hypertrophy, Right Ventricular; Hypoxia; Myocytes, Smooth Muscle; Proto-Oncogene Proteins c-akt; Rats; Resveratrol; Stilbenes

Resveratrol (3,4',5-trihydroxy-trans-stilbene) is known to enhance the cytotoxicity of the anticancer drug doxorubicin. On the other hand, breast cancer MCF-7 cells acquire resistance to doxorubicin under hypoxic conditions. In this study, we investigated the effect of resveratrol on hypoxia-induced resistance to doxorubicin in MCF-7 cells. Resveratrol and its derivative 3,5-dihydroxy-4'-methoxy-trans-stilbene, but not 3,5-dimethoxy-4'-hydroxy-trans-stilbene, cancelled hypoxia-induced resistance to doxorubicin at a concentration of 10 μM. Carbonyl reductase 1 (CBR1) catalyzes the conversion of doxorubicin to its metabolite doxorubicinol, which is much less effective than doxorubicin. Hypoxia increased the expression of CBR1 at both mRNA and protein levels, and knockdown of CBR1 inhibited hypoxia-induced resistance to doxorubicin in MCF-7 cells. Knockdown of hypoxia-inducible factor (HIF)-1α repressed the hypoxia-induced expression of CBR1. Resveratrol repressed the expression of HIF-1α protein, but not HIF-1α mRNA, and decreased hypoxia-activated HIF-1 activity. Resveratrol repressed the hypoxia-induced expression of CBR1 at both mRNA and protein levels. Likewise, 3,5-dihydroxy-4'-methoxy-trans-stilbene decreased the hypoxia-induced expression of CBR1 protein, but not 3,5-dimethoxy-4'-hydroxy-trans-stilbene. Furthermore, resveratrol decreased the expression of HIF-1α protein even in the presence of the proteasome inhibitor MG132 in hypoxia. Theses results indicate that in MCF-7 cells, HIF-1α-increased CBR1 expression plays an important role in hypoxia-induced resistance to doxorubicin and that resveratrol and 3,5-dihydroxy-4'-methoxy-trans-stilbene decrease CBR1 expression by decreasing HIF-1α protein expression, perhaps through a proteasome-independent pathway, and consequently repress hypoxia-induced resistance to doxorubicin.

Topics: Alcohol Oxidoreductases; Antineoplastic Agents; Breast Neoplasms; Doxorubicin; Drug Resistance, Neoplasm; Female; Humans; Hypoxia; Hypoxia-Inducible Factor 1, alpha Subunit; Leupeptins; MCF-7 Cells; Phytotherapy; Plant Extracts; Resveratrol; RNA, Messenger; Stilbenes

To detect the role of surviving (SVV) in the protective effect of resveratrol against hypoxia/reperfusion injury (H/RI) of cardiac microvascular endothelial cells (CMECs).. CMECs isolated from the hearts of adult rats were exposed to hypoxia (94% N₂, 5% CO₂, 1% O₂) for 2 h followed by 4 h reoxygenation (95% O₂, 5% CO₂). The cell proliferation of CMECs was measured by MTT assay and Transwell method was used to detect migration ability of CMEC, PI-AnnexinV double staining and flow cytometry technique were employed to observe the apoptotic rate of CMECs. The SVV protein expression was detected with Western blot method.. Compared to control group, the proliferation (0.19 ± 0.03 vs. 0.42 ± 0.07, P < 0.01) and migration ((28 ± 2)/5HPF vs. (50 ± 3)/5 HPF, P < 0.01) abilities were impaired and the apoptosis index ((19.7 ± 0.8)% vs. (5.4 ± 0.3)%, (P < 0.05) of CMEC was increased after H/RI. The proliferation (0.36 ± 0.07 vs. 0.19 ± 0.03, P < 0.05) and migration ((55 ± 3)/5HPF vs. (28 ± 2)/5HPF, P < 0.05) abilities of CMEC were significantly improved while the apoptosis index ((9.6 ± 0.7)% vs. (19.7 ± 0.8)%, P < 0.05) was significantly decreased in H/RI+resveratrol group compared to H/RI group.SVV protein expression was also upregulated in H/RI+resveratrol group compared to H/RI group (P < 0.05). To further ascertain the role of SVV in the protective effects of resveratrol, PI3K specific inhibitor LY294002 was added to H/RI+resveratrol group, the proliferation (0.25 ± 0.05 vs. 0.36 ± 0.07, P < 0.05) and migration ((34 ± 3)/5HPF vs. (55 ± 3)/5HPF, P < 0.05) abilities were significantly decreased, the apoptosis index ((16.2 ± 0.6)% vs. (9.6 ± 0.7)%, P < 0.05) was increased and the protein expression of SVV was downregulated (P < 0.05) in LY294002+H/RI+resveratrol group compared to H/RI+resveratrol group.. Resveratrol could significantly reduce H/RI induced apoptosis and attenuate H/RI induced cardiac microvascular endothelial cells dysfunction through up-regulating PI3K/Akt/SVV pathways.

Topics: Animals; Apoptosis; Cell Proliferation; Chromones; Endothelial Cells; Enzyme Inhibitors; Heart; Hypoxia; Morpholines; Myocardium; Myocytes, Cardiac; Phosphatidylinositol 3-Kinases; Proto-Oncogene Proteins c-akt; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Resveratrol; Stilbenes; Up-Regulation

Resveratrol has been shown to be a therapeutic agent for cardiovascular disorders by maintaining a lower redox level in vivo through its anti-oxidant properties. Resveratrol can prevent cells from p53- and reactive oxygen species-dependent apoptosis induced by interleukin-1b. We identified an inhibitory effect of resveratrol against oxidative stress and apoptosis using the TUNEL assay in NG-Nitro-l-arginine methyl ester-induced preeclampsia in rats. To investigate a possible association between resveratrol and the apoptosis caused by oxidative stress in vitro, assays for superoxide dismutase and malondialdehyde as well as flow cytometric analyses were conducted in HTR-8/SVneo cells after hypoxic treatment with or without resveratrol for 24 h. These data suggest that resveratrol significantly opposes the effects of oxidative stress in vivo and in vitro.

Topics: Animals; Antioxidants; Apoptosis; Blood Pressure; Cell Line; Disease Models, Animal; Female; Hypoxia; Oxidative Stress; Phenotype; Placenta; Pre-Eclampsia; Pregnancy; Rats; Resveratrol; Stilbenes; Trophoblasts

An in vitro model of ischemic cerebral stroke [oxygen-glucose deprivation (OGD) for 6 h followed by 24 h reoxygenation (R)] with PC12 cells increases Ca(2+) influx by upregulating native L-type Ca(2+) channels and reactive oxygen species (ROS) generation. This reactive oxygen species generation and increase in intracellular Ca(2+) triggers the expression of hypoxic homeostasis transcription factors such as hypoxia induced factor-1 alpha (HIF-1α), Cav-beta 3 (Cav β3), signal transducer and activator of transcription 3 (STAT3), heat shock protein 27 (hsp-27), and cationic channel transient receptor potential melastatin 7 (TRPM7). OGD insulted PC12 cells were subjected to biologically safe doses (5, 10, and 25 μM) of trans-resveratrol in three different treatment groups: 24 h prior to OGD (pre-treatment); 24 h post OGD (post-treatment); and from 24 h before OGD to end of reoxygenation period (whole-treatment). Here, we demonstrated that OGD-R-induced neuronal injury/death is by reactive oxygen species generation, increase in intracellular calcium levels, and decrease in antioxidant defense enzymes. trans-Resveratrol increases the viability of OGD-R insulted PC12 cells, which was assessed by using MTT, NRU, and LDH release assay. In addition, trans-resveratrol significantly decreases reactive oxygen species generation, intracellular Ca(2+) levels, and hypoxia associated transcription factors and also increases the level of antioxidant defense enzymes. Our data shows that the whole-treatment group of trans-resveratrol is most efficient in decreasing hypoxia induced cell death through its antioxidant properties.

Topics: Animals; Antioxidants; Calcium; Calcium Channels; Cell Death; Cell Hypoxia; HSP27 Heat-Shock Proteins; Hypoxia; Hypoxia-Inducible Factor 1, alpha Subunit; Ischemia; L-Lactate Dehydrogenase; PC12 Cells; Rats; Reactive Oxygen Species; Resveratrol; STAT3 Transcription Factor; Stilbenes; Superoxide Dismutase; Superoxide Dismutase-1; TRPM Cation Channels

Hypoxia modulates the production of proteins involved in e.g. inflammation, angiogenesis and glucose utilization and hypoxia may therefore be an important factor underlying adipose tissue dysfunction in obesity. Resveratrol (RSV) is a natural polyphenolic compound and has been shown to have powerful anti-inflammatory effects and beneficial effects on several obesity-related complications. Thus, in the present study we investigated whether RSV has effects on hypoxic markers (GLUT-1, VEGF), hypoxia-induced key markers of inflammation (IL8, IL6), and leptin in human adipose tissue in vitro. Hypoxia was induced by incubating human adipose tissue fragments with 1% O2 for 24h as compared to 21% O2 The gene expressions were investigated by RT-PCR and protein release by Elisa. Hypoxia increases the expression of glucose transporter-1 (GLUT-1) (19-fold, p<0.001), vascular endothelial growth factor (VEGF) (10-fold, p<0.05), interleukin-8 (IL8) (8-fold, p<0.05), interleukin-6 (IL6) (5-fold, p<0.05) and leptin (9-fold). The protein levels of VEGF released to the medium was increased (8-fold, p<0.01) by hypoxia. RSV dose-dependently inhibited several of these hypoxia-induced expressions and at a concentration of 50 μM RSV almost completely inhibited the hypoxic responses at the above mentioned gene expression levels (p<0.05-p<0.001) and significantly attenuated the hypoxia-induced protein releases by 50-60%. These results demonstrate that hypoxia induces extensive changes in human adipose tissue in the expression and release of inflammation and angiogenesis-related adipokines. In addition the inhibition of hypoxia-mediated inflammation and angiogenesis might represent a novel mechanism of RSV in preventing obesity-related pathologies.

Topics: Adipose Tissue; Adult; Angiogenesis Inhibitors; Anti-Inflammatory Agents; Female; Glucose Transporter Type 1; Humans; Hypoxia; In Vitro Techniques; Inflammation; Interleukin-6; Interleukin-8; Leptin; Neovascularization, Physiologic; Resveratrol; RNA, Messenger; Stilbenes; Vascular Endothelial Growth Factor A

Damage from oxidative stress plays a critical role in spinal cord injury. Nuclear factor erythroid 2-related factor (Nrf-2) signaling pathway can be activated by cellular oxidative stress. Resveratrol, a plant-derived polyphenolic compound found in red wine, has antioxidant properties. In the present study, we have examined the neuroprotective effect of resveratrol and the role of Nrf-2 in spinal cord hypoxic injury. The spinal cord was removed from adult male Wistar rats from T2-T10 and the dorsal column was used to induce hypoxic injury in vitro with and without treatment with resveratrol (50μM). Significant changes were found in the compound action potential (CAP) of spinal cord dorsal column, and hematoxyline and eosin (H&E) staining showed that resveratrol significantly improved neuronal injury. The biochemical assays showed significant changes in lipid peroxidase (LPO), reduced glutathione (GSH), superoxide dismutase (SOD), protein carbonyl (PC), mitochondrial ATP content, and mitochondrial Ca(++). Furthermore, using immunohistochemistry and Western blot, we found that after resveratrol treatment during hypoxic injury there was a significant activation of NrF-2 and down regulation of the glial fibrillary acidic protein (GFAP) content. The results show that resveratrol treatment has neuroprotective effects on CAP, Ca(++) loading, and biochemical parameters after hypoxic injury. The neuroprotective effect is likely to be exerted by increased activation of transcription factor Nrf-2 by resveratrol along with its direct antioxidant effect to ameliorate the oxidative damage and preserve mitochondrial function.

Topics: Animals; Antioxidants; Blotting, Western; Fluorescent Antibody Technique; Hypoxia; Immunohistochemistry; Male; Neuroprotective Agents; NF-E2-Related Factor 2; Oxidative Stress; Rats; Rats, Wistar; Resveratrol; Spinal Cord; Spinal Cord Injuries; Stilbenes

Resveratrol is known to exert a cardioprotective effect against hypoxia/reoxygenation (H/R) injury. HS-1793 is a novel, more stable resveratrol analog, but its cardioprotective effects were unknown. The present study aimed to test the cardioprotective effect of HS-1793 against H/R injury and investigate the role of mitochondria in Sprague Dawley rat heart damage using an ex vivo Langendorff system. HS-1793 ameliorated H/R-induced mitochondrial dysfunction by reducing mitochondrial reactive oxygen species production, improving mitochondrial oxygen consumption and suppressing mitochondrial calcium (Ca(2+)) overload during reperfusion. Moreover, HS-1793-treated rat heart showed reduced infarct size. Our data suggest that HS-1793 can protect cardiac against mitochondrial damage following H/R, thereby suppressing injury.

Topics: Animals; Calcium; Heart; Hypoxia; Mitochondria; Myocardial Reperfusion Injury; Naphthols; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Resorcinols; Resveratrol; Stilbenes

This pre-clinical study was designed to investigate the effect of various vascular disrupting agents (VDAs) that have undergone or are in clinical evaluation, had on the oxygenation status of tumours and what effects that could have on the combination with radiation.. The tumour model was a C3H mammary carcinoma grown in the right rear foot of female CDF1 mice and treated when at 200 mm(3) in size. The VDAs were the flavenoid compounds flavone acetic acid (FAA) and its more recent derivative 5,6-dimethylxanthenone-4-acetic acid (DMXAA), and the leading tubulin binding agent combretastatin A-4 phosphate (CA4P) and the A-1 analogue OXi4503. Oxygenation status was estimated using the Eppendorf oxygen electrode three hours after drug injection. Radiation response was determined following single or fractionated (10 fractions in 12 days) irradiations with a 240 kV x-ray machine using either a tumour re-growth or local tumour control assay.. All VDAs significantly reduced the oxygenation status of the tumours. They also influenced radiation response, but the affect was time and sequence dependent using single radiation schedules; an enhanced effect when the VDAs were injected at the same time or after irradiating, but no or even a reduced effect when given prior to irradiation. Only OXi4503 showed an increased response when given before the radiation. CA4P and OXi4503 also enhanced a fractionated radiation treatment if the drugs were administered after fractions 5 and 10.. VDAs clearly induced tumour hypoxia. This had the potential to decrease the efficacy of radiation. However, if the appropriate timing and scheduling were used an enhanced effect was observed using both single and fractionated radiation treatments.

Topics: Animals; Antineoplastic Agents; Blood Vessels; Chemoradiotherapy; Diphosphates; Female; Flavonoids; Hypoxia; Mammary Neoplasms, Experimental; Mice; Mice, Inbred C3H; Oxygen; Stilbenes; X-Ray Therapy; Xanthones

We have previously shown that adult offspring exposed to a prenatal hypoxic insult leading to intrauterine growth restriction (IUGR) are more susceptible to cardiovascular pathologies. Our objectives were to evaluate the interaction between hypoxia-induced IUGR and postnatal diet in the early development of cardiovascular pathologies. Furthermore, we sought to determine whether the postnatal administration of resveratrol could prevent the development of cardiovascular disorders associated with hypoxia-induced IUGR. On day 15 of pregnancy, Sprague-Dawley rats were randomly assigned to hypoxia (11.5% oxygen), to induce IUGR, or normal oxygen (control) groups. For study A, male offspring (3 wk of age) were randomly assigned a low-fat (LF, <10% fat) or a high-fat (HF, 45% fat) diet. For study B, offspring were randomized to either HF or HF+resveratrol diets. After 9 wk, cardiac and vascular functions were evaluated. Prenatal hypoxia and HF diet were associated with an increased myocardial susceptibility to ischemia. Blood pressure, in vivo cardiac function, and ex vivo vascular function were not different among experimental groups; however, hypoxia-induced IUGR offspring had lower resting heart rates. Our results suggest that prenatal insults can enhance the susceptibility to a second hit such as myocardial ischemia, and that this phenomenon is exacerbated, in the early stages of life by nutritional stressors such as a HF diet. Supplementing HF diets with resveratrol improved cardiac tolerance to ischemia in offspring born IUGR but not in controls. Thus we conclude that the additive effect of prenatal (hypoxia-induced IUGR) and postnatal (HF diet) factors can lead to the earlier development of cardiovascular pathology in rats, and postnatal resveratrol supplementation prevented the deleterious cardiovascular effects of HF diet in offspring exposed to prenatal hypoxia.

Topics: Animals; Blood Pressure; Body Weight; Diet, High-Fat; Female; Fetal Growth Retardation; Heart; Heart Rate; Hypoxia; Male; Pregnancy; Prenatal Exposure Delayed Effects; Rats; Rats, Sprague-Dawley; Resveratrol; Stilbenes

Hypoxic pulmonary hypertension is a life-threatening emergency if untreated. Consistent pulmonary hypertension also leads to arteries and ventricular remodeling. The clinical therapeutic strategy for pulmonary hypertension and the corresponding remodeling mainly interacts with NO, angiotensin II (Ang II) and elevated endothelin (ET) targets. In the present study, we evaluated the effects of polydatin on hypoxia-induced pulmonary hypertension. It was observed that polydatin attenuated hypoxic pulmonary hypertension, reversed remodeling, and regulated NO, Ang II, ET contents in the serum and lung samples. However, forced activation of PKC signaling by its selective activator thymeleatoxin (THX) could abate the effects of polydatain. These results suggest that polydatin might be a promising candidate for hypoxic pulmonary treatment through interaction with PKC mechanisms.

Topics: Angiotensin II; Animals; Endothelins; Glucosides; Hypertension, Pulmonary; Hypoxia; Male; Nitric Oxide; Phorbol Esters; Protein Kinase C; Rats; Rats, Sprague-Dawley; Signal Transduction; Stilbenes; Vascular Remodeling

Pulmonary arterial hypertension (PAH) is a hyperproliferative vascular disorder observed predominantly in women. Estrogen is a potent mitogen in human pulmonary artery smooth muscle cells and contributes to PAH in vivo; however, the mechanisms attributed to this causation remain obscure. Curiously, heightened expression of the estrogen-metabolizing enzyme cytochrome P450 1B1 (CYP1B1) is reported in idiopathic PAH and murine models of PAH.. Here, we investigated the putative pathogenic role of CYP1B1 in PAH. Quantitative reverse transcription-polymerase chain reaction, immunoblotting, and in situ analysis revealed that pulmonary CYP1B1 is increased in hypoxic PAH, hypoxic+SU5416 PAH, and human PAH and is highly expressed within the pulmonary vascular wall. PAH was assessed in mice via measurement of right ventricular hypertrophy, pulmonary vascular remodeling, and right ventricular systolic pressure. Hypoxic PAH was attenuated in CYP1B1(-/-) mice, and the potent CYP1B1 inhibitor 2,3',4,5'-tetramethoxystilbene (TMS; 3 mg · kg(-1) · d(-1) IP) significantly attenuated hypoxic PAH and hypoxic+SU5416 PAH in vivo. TMS also abolished estrogen-induced proliferation in human pulmonary artery smooth muscle cells and PAH-pulmonary artery smooth muscle cells. The estrogen metabolite 16α-hydroxyestrone provoked human pulmonary artery smooth muscle cell proliferation, and this mitogenic effect was greatly pronounced in PAH-pulmonary artery smooth muscle cells. ELISA analysis revealed that 16α-hydroxyestrone concentration was elevated in PAH, consistent with CYP1B1 overexpression and activity. Finally, administration of the CYP1B1 metabolite 16α-hydroxyestrone (1.5 mg · kg(-1) · d(-1) IP) caused the development of PAH in mice.. Increased CYP1B1-mediated estrogen metabolism promotes the development of PAH, likely via the formation of mitogens, including 16α-hydroxyestrone. Collectively, this study reveals a possible novel therapeutic target in clinical PAH.

Topics: Animals; Aryl Hydrocarbon Hydroxylases; Cell Hypoxia; Cells, Cultured; Chronic Disease; Cytochrome P-450 CYP1B1; Enzyme Induction; Estradiol; Estrogens; Female; Humans; Hydroxyestrones; Hypertension, Pulmonary; Hypertrophy, Right Ventricular; Hypoxia; Lung; Male; Mice; Mice, Knockout; Myocytes, Smooth Muscle; Pulmonary Artery; Reverse Transcriptase Polymerase Chain Reaction; Stilbenes; Up-Regulation

Orthodontic force causes gradual compression of the periodontal ligament tissues, which leads to local hypoxia in the compression side of the tissues. In this study, we investigated whether antioxidants exert a regulatory effect on two factors: the expression of pro-inflammatory cytokines in human periodontal ligament fibroblasts (PDLFs) that were exposed to mechanical compression and hypoxia and the rate of orthodontic tooth movement in rats. Exposure of PDLFs to mechanical compression (0.5-3.0 g/cm(2)) or hypoxic conditions increased the production of intracellular reactive oxygen species. Hypoxic treatment for 24 h increased the mRNA levels of IL-1β, IL-6 and IL-8 as well as vascular endothelial growth factor (VEGF) in PDLFs. Resveratrol (10 nM) or N-acetylcysteine (NAC, 20 mM) diminished the transcriptional activity of hypoxiainducible factor-1 and hypoxia-induced expression of VEGF. Combined treatment with mechanical compression and hypoxia significantly increased the expression levels of IL-1β, IL-6, IL-8, TNF-α and VEGF in PDLFs. These levels were suppressed by NAC and resveratrol. The maxillary first molars of rats were moved mesially for seven days using an orthodontic appliance. NAC decreased the amount of orthodontic tooth movement compared to the vehicle-treated group. The results from immunohistochemical staining demonstrated that NAC suppressed the expression of IL-1β and TNF-α in the periodontal ligament tissues compared to the vehicle-treated group. These results suggest that antioxidants have the potential to negatively regulate the rate of orthodontic tooth movement through the down-regulation of pro-inflammatory cytokines in the compression sides of periodontal ligament tissues.

Topics: Acetylcysteine; Animals; Antioxidants; Cells, Cultured; Fibroblasts; Humans; Hypoxia; Inflammation; Inflammation Mediators; Interleukin-1beta; Male; Molar; Periodontal Ligament; Rats; Rats, Sprague-Dawley; Resveratrol; Stilbenes; Stress, Mechanical; Tooth Mobility; Tumor Necrosis Factor-alpha; Up-Regulation

A prenatal hypoxic insult leading to intrauterine growth restriction (IUGR) increases the susceptibility to develop metabolic syndrome (MetS) later in life. Since resveratrol (Resv), the polyphenol produced by plants, exerts insulin-sensitizing effects, we tested whether Resv could prevent deleterious metabolic effects of being born IUGR.. Pregnant rats were exposed to either a normoxic (control; 21% O(2)) or a hypoxic (IUGR; 11.5% O(2)) environment during the last third of gestation. After weaning, male offspring were randomly assigned to receive either a high-fat (HF; 45% fat) diet or an HF diet with Resv (4 g/kg diet) for 9 weeks when various parameters of the MetS were measured.. Relative to normoxic controls, hypoxia-induced IUGR offspring developed a more severe MetS, including glucose intolerance and insulin resistance, increased intra-abdominal fat deposition and intra-abdominal adipocyte size, and increased plasma triacylglycerol (TG) and free fatty acids, as well as peripheral accumulation of TG, diacylglycerol, and ceramides. In only IUGR offspring, the administration of Resv reduced intra-abdominal fat deposition to levels comparable with controls, improved the plasma lipid profile, and reduced accumulation of TG and ceramides in the tissues. Moreover, Resv ameliorated insulin resistance and glucose intolerance as well as impaired Akt signaling in the liver and skeletal muscle of IUGR offspring and activated AMP-activated protein kinase, which likely contributed to improved metabolic parameters in Resv-treated IUGR rats.. Our results suggest that early, postnatal administration of Resv can improve the metabolic profile of HF-fed offspring born from pregnancies complicated by IUGR.

Topics: Animals; Antioxidants; Body Weight; Calorimetry, Indirect; Dietary Fats; Energy Intake; Female; Fetal Growth Retardation; Hypoxia; Insulin Resistance; Male; Metabolic Syndrome; Motor Activity; Pregnancy; Prenatal Exposure Delayed Effects; Rats; Resveratrol; Stilbenes

Incubation of rat striatal slices in anoxic medium caused significant alterations in dopamine (DA) and 3,4-dihydroxyphenylacetic acid (DOPAC) outputs; while DA release increased several times, 50% decline in DOPAC output was observed under this condition. Tissue ATP level, on the other hand, was decreased 40% by anoxia. Presence of resveratrol in the medium decreased anoxia-induced DA release in a concentration-dependent manner. Enhanced DA output, however, was declined slightly by epicatechine and catechine, and not altered significantly by morin hydrate and quercetin dehydrate which are other penolic compounds present in the red wine. In contrary to DA output, anoxia-induced decline in tissue ATP level was not ameliorated by resveratrol. In addition to anoxia, resveratrol, as observed with DA uptake blocker nomifensine, also reduced DA release stimulated by ouabain. Efficiencies of both resveratrol and nomifensine to attenuate ouabain-induced DA output, however, were closely dependent on ouabain concentration in the medium. These results indicate that some phenolic compounds, particularly resveratrol decrease anoxia-induced DA output and appear promising agents to improve the alterations occurred under anoxic-ischemic conditions.

Topics: 3,4-Dihydroxyphenylacetic Acid; Adenosine Triphosphate; Animals; Antioxidants; Corpus Striatum; Dopamine; Dopamine Uptake Inhibitors; Enzyme Inhibitors; Female; Hypoxia; Male; Nomifensine; Ouabain; Rats; Rats, Wistar; Resveratrol; Stilbenes

The objective was a comprehensive investigation of the mechanisms and sites of resveratrol cardioprotection during and following ischemia-reperfusion (I-R) injury, and to determine whether direct preservation of cardiomyocytes is an important site of cardioprotection. We now provide the first definitive evidence that resveratrol specifically protects cardiomyocytes from I-R injury via a combination of suppression of superoxide levels and activation of potassium channels. This protection is apparent whether resveratrol is present for the full duration of the insult or only on recovery. In addition, resveratrol improved postischemic recovery of left ventricular contractile function, attenuated myocardial injury, and increased myocardial activation of the survival kinase Akt in the intact heart. Furthermore, resveratrol elicited direct concentration-dependent protective actions on the vasculature (vasorelaxation, superoxide suppression) and enhanced endothelium-dependent vasodilatation. Resveratrol thus targets a number of consequences of myocardial I-R, including release of reactive oxygen species, loss of recovery of contractile function, and impaired endothelium-dependent vasodilatation. Previous evidence indicates that resveratrol elicits potent preconditioning in the heart. Given that myocardial ischemic events are often unpredictable in humans, the findings that resveratrol protection is also evident when administered during and/or after the insult adds new dimensions to the clinical potential of resveratrol.

Topics: Animals; Antioxidants; Carotid Arteries; Dose-Response Relationship, Drug; Endothelial Cells; Heart; Humans; Hypoxia; In Vitro Techniques; Male; Myocytes, Cardiac; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Resveratrol; Stilbenes

Topics: Animals; Antioxidants; Brain Ischemia; DNA, Mitochondrial; Flavonoids; Humans; Hypoxia; Mice; Mitochondria; Models, Biological; Phenols; Polyphenols; Reactive Oxygen Species; Reperfusion Injury; Resveratrol; Stilbenes; Stroke

The cardiac Na(+)/Ca(2+) exchanger (NCX) contributes to cellular injury during hypoxia, as its altered function is largely responsible for a rise in cytosolic Ca(2+) concentration ([Ca(2+)](i)). In addition, the NCX in guinea pig ventricular myocytes undergoes profound inhibition during hypoxia and rapid reactivation during reoxygenation. The mechanisms underlying these changes in NCX activity are likely complex due to the participation of multiple inhibitory factors including altered cytosolic Na(+) concentration, pH, and ATP. Our main hypothesis is that oxidative stress is an essential trigger for rapid NCX reactivation in guinea pig ventricular myocytes and is thus a critical factor in determining the timing and magnitude of Ca(2+) overload. This hypothesis was evaluated in cardiac myocytes using fluorescent indicators to measure [Ca(2+)](i) and oxidative stress. An NCX antisense oligonucleotide was used to decrease NCX protein expression in some experiments. Our results indicate that NCX activity is profoundly inhibited in hypoxic guinea pig ventricular myocytes but is reactivated within 1-2 min of reoxygenation at a time of rising oxidative stress. We also found that several interventions to decrease oxidative stress including antioxidants and diazoxide prevented NCX reactivation and Ca(2+) overload during reoxygenation. Furthermore, application of exogenous H(2)O(2) was sufficient by itself to reactivate the NCX during sustained hypoxia and could reverse the suppression of reoxygenation-mediated NCX reactivation by diazoxide. These data suggest that elevated oxidative stress in reoxygenated guinea pig ventricular myocytes is required for rapid NCX reactivation, and thus reactivation should be viewed as an active process rather than being due to the simple decline of NCX inhibition.

Topics: Animals; Antioxidants; Cells, Cultured; Chromans; Diazoxide; Free Radical Scavengers; Guinea Pigs; Heart Ventricles; Hypoxia; Metalloporphyrins; Myocardial Reperfusion Injury; Myocytes, Cardiac; Oxidative Stress; Reactive Oxygen Species; Resveratrol; Sodium-Calcium Exchanger; Stilbenes

Reactive oxygen intermediates (ROIs) are important mediators of a variety of pathological processes, including inflammation and ischemia/reperfusion injury. Cytokines and chemokines are detected at mRNA level in human and animal ischemic brains. This suggests that hypoxia/reoxygenation may induce cytokine production through generation of ROIs. In this study, we investigated the cytokine induction and inhibition by antioxidants in rat cortical mixed glial cells exposed to in vitro ischemia-like insults (hypoxia plus glucose deprivation). The results showed that interleukin-6 (IL-6) mRNA and protein, but not tumor necrosis factor-alpha (TNF-alpha) or interleukin-1beta (IL-1beta), were induced during hypoxia/hypoglycemia followed by reoxygenation in the mixed glial cells. The accumulation of IL-6 mRNA was induced as early as 15 min after hypoxia/hypoglycemia and its level was further increased after subsequent reoxygenation. Among the antioxidants studied, only resveratrol suppressed IL-6 gene expression and protein secretion in mixed glial cultures under hypoxia/hypoglycemia followed by reoxygenation. These findings suggest that resveratrol might be useful in treating ischemic-induced inflammatory processes in stroke.

Topics: Animals; Antioxidants; Cerebral Cortex; Hyperglycemia; Hypoxia; Interleukin-6; Neuroglia; NF-kappa B; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Resveratrol; Stilbenes