iridoids and Hypoxia

As the main effector cells of chronic inflammation and hyperplasia of synovium, fibroblast-like synoviocytes (FLSs) show abnormal proliferation and insufficient apoptosis in the hypoxic microenvironment, which is due to the increase of BNIP3-mediated autophagy. This study aimed to explore the mechanism of geniposide (GE) on hypoxia-induced hyper-proliferative FLSs with a focus on autophagy and the JNK-BNIP3 pathway.. The dynamic changes of autophagy, apoptosis, and hypoxia-related proteins in adjuvant arthritis (AA) rats were detected by immunohistochemistry and Western blot. The proliferation, autophagy, apoptosis, and mitochondrial state of FLSs were detected by CCK-8, flow cytometry, immunofluorescence, and transmission electron microscopy, respectively. Western blot, qRT-PCR, and co-immunoprecipitation were used to detect the expression of the JNK-BNIP3 pathway.. The excessive accumulation of BNIP3 in the synovium of AA rats was accompanied by inhibition of apoptosis and an increase in autophagy. GE inhibited the expression of BNIP3, enhanced apoptosis, decreased autophagy, and improved chronic inflammation and hyperplasia of synovium. The amount of autophagy under different oxygen concentrations was the key to mediating the different survival rates of FLSs, and the inhibition of autophagy triggered apoptosis. GE suppressed the proliferation of FLSs and down-regulated autophagy, leading to the accumulation of ROS and the decrease of mitochondrial membrane potential, induced the increase of apoptosis, and suppressed the accumulation of BNIP3 and the hyperphosphorylation of JNK.. GE inhibited autophagy by restoring the hypoxia-induced activated JNK-BNIP3 pathway, inducing mitochondrial oxidative damage, augmented apoptosis, and decreased survival rate of FLSs.

Topics: Animals; Apoptosis; Arthritis, Experimental; Autophagy; Fibroblasts; Hyperplasia; Hypoxia; Inflammation; Iridoids; Membrane Proteins; Mitochondrial Proteins; Rats; Synoviocytes

Background Neurological deficits in hypoxic-ischemic encephalopathy, even with therapeutic hypothermia, are partially attributed to white matter injury. We theorized that proteasome insufficiency contributes to white matter injury. Methods and Results Neonatal piglets received hypoxia-ischemia ( HI ) or sham procedure with normothermia, hypothermia, or hypothermia+rewarming. Some received a proteasome activator drug (oleuropein) or white matter-targeted, virus-mediated proteasome knockdown. We measured myelin oligodendrocyte glycoprotein, proteasome subunit 20S (P20S), proteasome activity, and carbonylated and ubiquitinated protein levels in white matter and cerebral cortex. HI reduced myelin oligodendrocyte glycoprotein levels regardless of temperature, and myelin oligodendrocyte glycoprotein loss was associated with increased ubiquitinated and carbonylated protein levels. Ubiquitinated and carbonyl-damaged proteins increased in white matter 29 hours after HI during hypothermia to exceed levels at 6 to 20 hours. In cortex, ubiquitinated proteins decreased. Ubiquitinated and carbonylated protein accumulation coincided with lower P20S levels in white matter; P20S levels also decreased in cerebral cortex. However, proteasome activity in white matter lagged behind that in cortex 29 hours after HI during hypothermia. Systemic oleuropein enhanced white matter P20S and protected the myelin, whereas proteasome knockdown exacerbated myelin oligodendrocyte glycoprotein loss and ubiquitinated protein accumulation after HI . At the cellular level, temperature and HI interactively affected macroglial P20S enrichment in subcortical white matter. Rewarming alone increased macroglial P20S immunoreactivity, but this increase was blocked by HI . Conclusions Oxidized and ubiquitinated proteins accumulate with HI -induced white matter injury. Proteasome insufficiency may drive this injury. Hypothermia did not prevent myelin damage, protect the proteasome, or preserve oxidized and ubiquitinated protein clearance after HI .

Topics: Animals; Animals, Newborn; Asphyxia; Brain Ischemia; Cerebral Cortex; Gene Knockdown Techniques; Heart Arrest; Hypothermia; Hypoxia; Iridoid Glucosides; Iridoids; Leukoencephalopathies; Male; Myelin-Oligodendrocyte Glycoprotein; Proteasome Endopeptidase Complex; Random Allocation; Rewarming; Swine; White Matter

Previously, we reported that high-fat-diet (HFD)-induced obesity stimulates melanoma progression in the B16F10 allograft model. In this study, we examined whether oleuropein (OL), the most abundant phenolic compound in olives, inhibits HFD-induced melanoma progression. Four-week-old male C57BL/6N mice were fed a HFD-diet with or without OL. After 16 weeks of feeding, B16F10-luc cells were subcutaneously injected and the primary tumor was resected 3 weeks later. OL suppressed HFD-induced solid tumor growth. In the tumor tissues, OL reduced HFD-induced expression of angiogenesis (CD31, VE-cadherin, VEGF-A, and VEGFR2), lymphangiogenesis (LYVE-1, VEGF-C, VEGF-D, and VEGFR3), and hypoxia (HIF-1α and GLUT-1) markers as well as HFD-induced increases in lipid vacuoles and M2 macrophages (MΦs). All animals were euthanized 2.5 weeks after tumor resection. OL suppressed HFD-induced increases in lymph node (LN) metastasis; expression of VEGF-A, VEGF-C, and VEGF-D in the LN; and M2-MΦs and the size of adipocytes in adipose tissues surrounding LNs. Co-culture results revealed that the crosstalk between B16F10s, M2-MΦs, and differentiated 3T3-L1 cells under hypoxic conditions increased the secretion of VEGF-A and -D, which stimulated tube formation and migration of endothelial cells (HUVECs) and lymphatic endothelial cells (LEC), respectively. Additionally, OL directly inhibited the differentiation of 3T3-L1 preadipocytes and tube formation by HUVECs and LECs. The overall results indicated that dietary OL inhibits lipid and M2-MΦ accumulation in HFD-fed mice, which contributes to decreases in VEGF secretion, thereby leading to inhibition of angiogenesis and lymphangiogenesis.

Topics: Adipose Tissue; Allografts; Angiogenesis Inhibitors; Animals; Apoptosis; Cell Proliferation; Diet, High-Fat; Dietary Supplements; Hypoxia; Iridoid Glucosides; Iridoids; Lipid Metabolism; Lymphangiogenesis; Lymphatic Metastasis; Macrophages; Melanoma, Experimental; Mice; Neovascularization, Pathologic; Tumor Burden; Vascular Endothelial Growth Factors

Radiotherapy in ovarian cancer frequently invokes resistance; this severely compromises its therapeutic effect and results in poor clinical prognosis. How to overcome the acquired resistance and re-sensitize tumors to radiation is the central question in this clinical setting. Cancer cell survival was evaluated using a clonogenic assay. The microRNA expression profile was analyzed using a microarray. Transcript expression was determined using real time PCR. The expression of protein was determined by immunoblotting. Transcription activation was measured using a luciferase reporter assay. Transcription factor binding was determined using ChIP-PCR. Xenograft model was established and exposed to radiation with the simultaneous administration of oleuropein. Tumor growth was monitored. We demonstrated that treatment of oleuropein-sensitized ovarian cells with radiation altered the microRNA expression profile. The endogenous expression of miR-299 was suppressed by a hypoxia inducible factor and relieved in response to oleuropein, which in turn suppressed HPSE1 expression and consequently led to increased sensitivity to radiation. Our data elucidates an unappreciated mechanism mediating radiotherapy resistance in ovarian cancer and exploits the potential synergistic effect of oleuropein with radiation, which warrants further clinical investigation.

Topics: Animals; Cell Line, Tumor; Female; Gene Expression Regulation, Neoplastic; Glucuronidase; Humans; Hypoxia; Iridoid Glucosides; Iridoids; Mice; Mice, Inbred BALB C; MicroRNAs; Ovarian Neoplasms; Radiation-Sensitizing Agents

To clarify the protective roles of compatibility of geniposide and ginsenoside (Rg1) in regulating ischemia injured microglia homeostasis by comparing the difference in regulatory roles of geniposide, Rg1, or ginsenoside + Rg1 in balancing secretion of oxygen glucose deprivation induced microglia inflammatory cytokines.. The mimic ischemia injured microglia model was induced by oxygen-glucose deprivation (OGD). Then geniposide, Rg1, or ginsenoside + Rg1 (Tongluo Jiunao Injection, TJI) was respectively added. The NO content was determined by Griess Reagent. The cyto activity was detected using cell count kit. Contents of TNF-alpha and TGF-beta and their expression levels were detected by ELISA and Western blot.. Geniposide + Rg1 could significantly inhibit the release of NO, elevate the TGF-beta level, and decrease the content of TNF-alpha without influencing the cell survival. The two active ingredients played different therapeutic roles. The compatible use was obviously superior to use any one of the two active ingredients alone.. Geniposide, Rg1, or Ginsenoside + Rg1 had regulating roles in balancing ischemia injured microglia homeostasis. Its mechanisms might be related to up-regulating the TGF-beta expression and down-regulating TNF-alpha expression.

Topics: Animals; Ginsenosides; Hypoxia; Iridoids; Mice; Microglia; Nitric Oxide; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

To investigate the protective mechanism of geniposide, baicalin and berberine on hypoxia and reoxygenation injury in cultured rat cerebral microvascular endothelial cells.. A model of four hours hypoxia and twelve hours reoxygenation injury in rat cerebral microvascular endothelial cells in vitro was established. The injured cells were treated with geniposide (0.128, 0.064, 0.032 mmol x L(-1)), baicalin (0.028, 0.014, 0.007 mmol L(-1)) and berberine (0.024, 0.012, 0.006 mmol L(-1)), respectively. The immunocytochemical method and techniques of image quantitative analysis were used to detect the mean optical density and mean area in order to match the protein expression of VCAM-1. The method of RT-PCR was adopted to observe and match the mRNA expression of VCAM-1.. As compared with the normal group, the mean optical density, the mean area and the mRNA expression of VCAM-1 of model group were significant increased (P < 0.01, P < 0.01, P < 0.01). As compared with the model group, both the mean optical density and the mean area of all treated groups were decreased, and there was significant difference between them (P < 0.01, P < 0.01). As compared with normal group, the mean optical density of baicalin (0.007 mmol x L(-1)) and berberine (0.012, 0.006 mmol x L(-1)) were significant decreased (P < 0.05, P < 0.01, P < 0.01), but there was no significant difference between the other groups and the normal group. As compared with normal group, the mean area of baicalin (0.0014 mmol x L(-1)) was significant decreased (P < 0.05), but there was significant difference between the other groups and the normal group. The mRNA expression of all treated groups was not only lower than that of the model group but also higher than that of the normal group (P < 0.05, P < 0.05).. The results suggest that geniposide, baicalin and berberine, which are effective compositions of huanglian jiedu decoting, can protect hypoxia-reoxygenation injuried rat cerebral microvascular endothelial cells. One of the protected mechanisms is that they can inhibit the expression of VCAM-1.

Topics: Animals; Berberine; Cell Hypoxia; Cells, Cultured; Cerebrum; Drugs, Chinese Herbal; Endothelium, Vascular; Flavonoids; Gene Expression; Humans; Hypoxia; Iridoids; Male; Oxygen; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Vascular Cell Adhesion Molecule-1

Catalpol has been identified to have neuroprotective effect on gerbils subjected to transient global cerebral ischemia. However, the mechanism that catalpol prevents ischemia is still unclear. In the present study, PC12 cells, exposed to oxygen and glucose deprivation (OGD) followed by reperfusion, were used as an in vitro model of ischemia. The protective effects of catalpol were investigated in ischemic-induced apoptosis in PC12 cells.. After OGD for 3 hours and reoxygenation for 18 hours, cell survival was quantified by the reduction of 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). The activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) were determined using commercially available kits. Caspase-3 assay was performed using caspase-3 assay kit. Microplate reader was used to detect the intensities of rhodamine123 (Rh123) and reactive oxygen species (ROS). The level of Bcl-2 protein was measured by flow cytometry.. Catalpol attenuated ischemia-induced apoptotic death via preventing the decrease in the level of Bcl-2 protein and the activities of SOD and GSH-PX, inhibiting the reduction of mitochondrial membrane potential and suppressing activation of caspase-3.. The results suggest that the catalpol has the potential to prevent ischemic-induced apoptosis.

Topics: Animals; Apoptosis; Caspase 3; Cell Count; Dose-Response Relationship, Drug; Drugs, Chinese Herbal; Glucose; Glucosides; Glutathione Peroxidase; Hypoxia; Iridoid Glucosides; Iridoids; Membrane Potential, Mitochondrial; PC12 Cells; Proto-Oncogene Proteins c-bcl-2; Rats; Reactive Oxygen Species; Superoxide Dismutase

Geniposide from Gardenia jasminoides protected neuronal cells from damage in oxygen and glucose deprivation-exposed hippocampal slice culture. Geniposide showed a greater protective effect on the granule cell layer than on the pyramidal cell layer including CA 1 and CA 3. On the basis of the experimental results, geniposide may be a therapeutic agent for ischemia in patients.

Topics: Animals; Cell Death; Gardenia; Glucose; Hippocampus; Hypoxia; Iridoids; Neurons; Organ Culture Techniques; Pyramidal Cells; Pyrans; Rats; Rats, Sprague-Dawley