astaxanthine and Reperfusion-Injury

Oxidative stress induced by Reactive Oxygen Species (ROS) was shown to be involved in the pathogenesis of chronic diseases such as cardiovascular pathologies. Particularly, oxidative stress has proved to mediate abnormal platelet function and dysfunctional endothelium-dependent vasodilatation representing a key factor in the progression of ischemic injuries. Antioxidants like carotenoids have been suggested to contribute in their prevention and treatment. Astaxanthin, a xanthophyll carotenoid produced naturally and synthetically, shows interesting antioxidant and anti-inflammatory properties. In vivo studies applying different models of induced ischemia and reperfusion (I/R) injury confirm astaxanthin's protective action after oral or intravenous administration. However, some studies have shown some limitations after oral administration such as low stability, bioavailability and bioefficacy, revealing a need for the implementation of new biomaterials to act as astaxanthin vehicles in vivo. Here, a brief overview of the chemical characteristics of astaxanthin, the carrier systems developed for overcoming its delivery drawbacks and the animal studies showing its potential effect to treat I/R injury are presented.

Topics: Animals; Antioxidants; Reactive Oxygen Species; Reperfusion Injury; Xanthophylls

Disodium disuccinate astaxanthin has potent cardioprotective effects in animals, with demonstrated preclinical efficacy in the rat, rabbit, and canine models of experimental infarction. It has been effective in subchronic and acute dosing regimens after parenteral administration, and recently published data in rats demonstrate that oral cardioprotection is also readily achieved. Myocardial salvage in the canine can reach 100% with a 4-day subchronic dosing regimen; single-dose I.V. cardioprotection, when given 2 hours before experimental coronary occlusion, is on average two-thirds of that achieved with the subchronic regimen in dogs. In conscious animals, no effects on hemodynamic parameters have been observed. Recently, the beneficial properties of this prototypical astaxanthin conjugate have been extended to include second- and third-generation compounds with improved pharmacokinetic and/or potency profiles. The primary mechanism of cardioprotection appears to be antioxidant activity: potent direct scavenging of the lynchpin radical in ischemia-reperfusion injury, superoxide anion, has been documented in appropriate model systems. In addition, modulation of serum complement activity, reduction of the levels of deposition of C-reactive protein (CRP) and the membrane attack complex (MAC) in infarcted tissue, and reduction in oxidative stress markers from the arachidonic acid and linoleic acid pathways also suggest a significant anti-inflammatory component to the mechanism of cardioprotection. Favorable plasma protein binding has been demonstrated in vitro for several astaxanthin conjugates; this binding capacity overcomes the supramolecular assembly of the compounds that occurs in aqueous solution, which in itself improves the stability and shelf-life of aqueous formulations. Astaxanthin readily populates cardiac tissue after metabolic hydrolysis of both oral and parenteral administration of the astaxanthin ester derivates, providing a reservoir of cardioprotective agent with a significant half-life due to favorable ADME in mammals. Due to the well-documented safety profile of astaxanthin in humans, disodium disuccinate astaxanthin may well find clinical utility in cardiovascular applications in humans following successful completion of preclinical and clinical pharmacology and toxicology studies in animals and humans, respectively.

Topics: Animals; Antioxidants; Drug Design; Drug Evaluation, Preclinical; Humans; Protective Agents; Reactive Oxygen Species; Reperfusion Injury; Succinates; Xanthophylls

The aim of this study was to investigate the effects of astaxanthin (ASX) on testicular torsion/detorsion (T/D) damage in rats in terms of oxidative stress and endoplasmic reticulum (ER) stress.. Eighteen male Sprague-Dawley rats were divided into three groups with six rats in each group: control, T/D and T/D + 20 mg/kg ASX. Torsion and detorsion times were applied as 4 h and 2 h, respectively. ASX application was performed 30 minutes before detorsion. At the end of the period, testicular tissues were removed and biochemical and histological analyzes were performed. To evaluate the degree of oxidative stress, tissue malondialdehyde (MDA), total oxidant status (TOS) and total antioxidant status (TAS) were determined using colorimetric methods, while tissue superoxide dismutase (SOD) levels were determined using ELISA kit. To evaluate the degree of ER stress, tissue glucose regulatory protein 78 (GRP78), activating transcription factor 6 (ATF6) and C/EBP homologous protein (CHOP) levels were determined using ELISA kits. Johnsen's testicle scoring system was used for histological evaluation.. In the T/D group, it is determined that statistically significant decreasing in TAS, SOD levels and Johnsen score, and increasing in TOS, OSI, MDA, GRP78, ATF6 and CHOP levels (p < 0.001) compared with control group. ASX administration statistically significantly restored this T/D-induced damage (p < 0.01).. This is the first study to show that ASX prevent T/D-induced testicular damage through its antioxidant activity. More comprehensive studies are needed to see the underlying mechanisms.

Topics: Animals; Antioxidants; Endoplasmic Reticulum Stress; Humans; Male; Malondialdehyde; Oxidative Stress; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Spermatic Cord Torsion; Superoxide Dismutase; Xanthophylls

Excitotoxicity and oxidative stress are central to the pathology of the nervous system, and inhibition of excitotoxicity induced by glutamate is one of the therapeutic goals determined for stroke. The present study aimed to investigate the effects of Astaxanthin, a potent natural antioxidant, on complications caused by acute cerebral stroke. In this research, 60 male Wistar rats were used which were divided into 5 groups as follow: (1) the sham group (vehicle), (2) the ischemic control group (vehicle), and the ischemic groups treated by Astaxanthin with doses of 25, 45, and 65 mg/kg. In the ischemic groups, ischemic model was performed by middle cerebral artery occlusion (MCAO) method, and the Astaxanthin administration was carried out after the artery occlusion and before opening the artery. The obtained results indicated that Astaxanthin could significantly reduce stroke volume, neurological deficits, and lipid peroxidation. Moreover, it was able to restore total oxidant status (TOS) and caspase 3 level to the normal level. The activity of antioxidant enzyme glutathione peroxidase (GPX), and the expression of catalase, GPx and nuclear factor kappa B (NFκb) genes, which were reduced after ischemia, were increased. This phenomenon was particularly pronounced for glutamate transporter 1 (GLT-1). Furthermore, Astaxanthin decreased the augmented pro-apoptotic gene Bax and restored the reduced Bcl2 expression to the normal level. Significant effects on the P53 and PUMA expression were not observed. Overall, the medium dosage of Astaxanthin appears to be more effective in reducing the complications of ischemia, particularly on our major study endpoints (stroke volume and neurological defects). Longer studies with a more frequent administration of Astaxanthin are required to better understand the precise mechanism of Astaxanthin.

Topics: Animals; Antioxidants; Brain Injuries; Brain Ischemia; Disease Models, Animal; Infarction, Middle Cerebral Artery; Male; Neuroprotective Agents; Rats; Rats, Wistar; Reperfusion; Reperfusion Injury; Stroke; Xanthophylls

Astaxanthin is a powerful biological antioxidant and is naturally generated in a great variety of living organisms. Some studies have demonstrated the neuroprotective effects of ATX against ischemic brain injury in experimental animals. However, it is still unknown whether astaxanthin displays neuroprotective effects against severe ischemic brain injury induced by longer (severe) transient ischemia in the forebrain. The purpose of this study was to evaluate the neuroprotective effects of astaxanthin and its antioxidant activity in the hippocampus of gerbils subjected to 15-min transient forebrain ischemia, which led to the massive loss (death) of pyramidal cells located in hippocampal cornu Ammonis 1-3 (CA1-3) subfields. Astaxanthin (100 mg/kg) was administered once daily for three days before the induction of transient ischemia. Treatment with astaxanthin significantly attenuated the ischemia-induced loss of pyramidal cells in CA1-3. In addition, treatment with astaxanthin significantly reduced ischemia-induced oxidative DNA damage and lipid peroxidation in CA1-3 pyramidal cells. Moreover, the expression of the antioxidant enzymes superoxide dismutase (SOD1 and SOD2) in CA1-3 pyramidal cells were gradually and significantly reduced after ischemia. However, in astaxanthin-treated gerbils, the expression of SOD1 and SOD2 was significantly high compared to in-vehicle-treated gerbils before and after ischemia induction. Collectively, these findings indicate that pretreatment with astaxanthin could attenuate severe ischemic brain injury induced by 15-min transient forebrain ischemia, which may be closely associated with the decrease in oxidative stress due to astaxanthin pretreatment.

Topics: Animals; Antioxidants; Brain Injuries; Gerbillinae; Hippocampus; Ischemia; Neuroprotective Agents; Oxidative Stress; Reperfusion Injury; Superoxide Dismutase-1; Xanthophylls

We aimed to compare biochemical and histopathological findings of astaxanthin's potential effects on oxidative stress in ischemia/reperfusion damage (I/R).. Thirty-two rats were randomly divided into four groups: control group; I/R group; I/R + treatment group; drug group. Astaxanthin was orally administered to groups C and D for 14 days. In groups B and C, the femoral artery was clamped for 2 h to form ischemia. The clamp was opened, and reperfusion was performed for 1 h. In all groups, 4 ml of blood sample through intracardiac puncture and gastrocnemius muscle tissue samples were collected. Serum and tissue samples were analyzed by measuring malondialdehyde (MDA), superoxide dismutase (SOD), total antioxidant capacity (TAC), and total oxidative level (TOL). Necrosis, inflammation, and caspase-3 in muscle tissue collected for histopathological examination were evaluated.. Tissue MDA, SOD and TOL values significantly differed between groups. Serum MDA, SOD, TOL and TAC values significantly differed between groups. On necrosis examination, there was a significant difference between groups B and C. Although signs of inflammation significantly differed between groups, there was no significant difference between groups A and C and groups A and D. Although there was a significant difference in caspase-3 results between groups, there was no significant difference between groups A and C.. The use of astaxanthin before and after surgery showed preventive or therapeutic effects against I/R damage.

Topics: Animals; Antioxidants; Caspase 3; Inflammation; Necrosis; Oxidative Stress; Rats; Reperfusion Injury; Superoxide Dismutase; Xanthophylls

Various effects of Astaxanthin were shown in the studies, including its antioxidant, anti-inflammatory, anti-tumor and immunoregulatory effects.. The aim of this study was to evaluate the beneficial effects of Astaxanthin on renovascular occlusion induced renal injury and to investigate the possible mechanisms.. The rats were randomly assigned into three groups as follows: Group 1: control group (n=12), Group 2: renal ischemia-reperfusion injury group (n=12), Group 3: renal ischemia-reperfusion + asthaxantine treated group (n=12). The control group and the renal ischemia-reperfusion group were given 2cc/kg/g olive oil for 7 days before establishing ischemia to renal tissue. Astaxanthin dissolved in olive oil was given orally to the renal ischemia+astaxanthin group for 7 days before inducing renal ischemia. Caspase-(3, 8, 9), GSH, SOD, Total Thiol, TNF-α, IL-6, 8-OHdG were evaluated in each group.. Renal IRI was verified by analysing the pathological changes of renal tissues and the renal functions after renal reperfusion. Much less renal tubular damage was determined in the IRI+ASX group in comparison to the IRI group. Caspase-8, -9 and -3 immunoreactivity was observed to be minimal in the control group. Apoptosis was observed to be significantly reduced in the IRI + ASX group with respect to the IRI group and close to the level of the control group (p <0.05). Caspase-3 levels of tissue samples were significantly increased in the IRI group compared to the other groups, but significantly lower in the IRI+ASX group with respect to the IRI group (p<0.05). The TOS and OSI levels, indicating increased oxidative stress, were significantly lower in the IRI+ASX group with respect to the IRI group (p <0.001), but still higher than the control group (p <0.001). In addition to GSH, SOD and Total Thiol levels, TAS levels were also significantly higher in the IRI + ASX group in comparison to the IRI group (p <0.05). TNF-α, IL-6, lipid hydroperoxide, AOPP and 8-OHdG levels were lower in the IRI+ASX group than the IRI group (p <0.001). MPO, IL-6, TNF-α levels, representing the parameters indicating neutrophil infiltration and inflammation of the renal tissues, significantly increased in the IRI group with respect to the other groups (p <0.005).. When all the data obtained in our study were evaluated, ASX was determined to prevent renal damage due to renovascular occlusion to a great extent, through complex mechanisms involving antioxidant, anti-inflammatory and antiapoptotic effects. Biochemical, histological and oxidative stress parameters were improved due to ASX.

Topics: Animals; Kidney; Oxidative Stress; Rats; Reperfusion Injury; Xanthophylls

Testicular torsion is one of the conditions of the acute scrotum that requires immediate surgical intervention. If not recognized at time, it can result of ischemic injuries and testicular loss. Restoration of blood flow is essential to save ischemic tissue, but reperfusion itself paradoxically causes further damage. Seaweed and sponges are considered to be the richest source of bioactive compounds that have antioxidant activity. The antioxidant activity of astaxanthin is 10 times higher than zeaxanthin, lutein, canthaxanthin, β-carotene and 100 times higher than α-tocopherol. Since to date there is no drug given to patients with torsion-detorsion testicular injury, we have investigated the effect of this powerful antioxidant.. The aim of this study was to determine the effect of astaxanthin (ASX) on testicular torsion-detorsion injury in rats.. Thirty-two male Fischer prepubertal rats were divided into 4 groups of 8 individuals. Group 1 underwent sham surgery to determine basal values for histological evaluation. In group 2 (torsion-detorsion group), right testis was twisted at 720° for 90 min. After 90min of reperfusion, the testis was removed. Astaxanthin was administered intraperitoneally at the time of detorsion (group 3) and 45 min after detorsion (group 4) in the treatment groups. Using software ImageJ®, histological morphometric values were measured.. MSTD (mean seminiferous tubule diameter) values increase statistically significantly in ASX groups compared to T/D group. MSLD (mean seminiferous lumen diameter) value was statistically significantly lower in the ASX group 3 compared to the T/D group. Epithelial height was statistically significantly higher in ASX groups compared to the T/D group. Tubular area is statistically significantly higher in ASX group 4, while the luminal area is statistically significantly lower in the ASX group 3 compared to the T/D group. Johnsen score was statistically significantly higher in the ASX groups compared to the T/D group.. This is the first scientific paper to study the effects of a single powerful antioxidant on all morphometric parameters. In previous scientific papers, scientists have mainly measured MSTD and the Johnsen score.. By measuring all histological morphometric parameters (mean seminiferous tubule diameter, mean seminiferous lumen diameter, epithelial height, tubular area, luminal area, Johnsen score) it can be concluded that astaxanthin has a favorable effect comparing the treated groups to untreated group.

Topics: Animals; Humans; Male; Malondialdehyde; Rats; Reperfusion Injury; Spermatic Cord Torsion; Testis; Xanthophylls

Skin flaps are the first-line treatment modality for skin defect reconstruction. With the increased importance and use of flap surgery, a growing number of studies have investigated the ways for the prevention of ischemia-reperfusion injury. The aim of this study was to investigate the effect of astaxanthin, which is an antioxidant molecule from the xanthophyll family, on the survival of random pattern skin flaps.. Thirty-two Sprague-Dawley rats with a caudally based random pattern skin flap (3 × 9 cm) were divided into 4 groups: group A (astaxanthin orally 1 mg/kg per day), group B (astaxanthin orally 4 mg/kg per day), group C (astaxanthin orally 16 mg/kg per day), and the control group. On postoperative day 7, the flaps were evaluated by photographic, scintigraphic, and histological methods. Photographs were taken to investigate the total flap, necrotic flap, and surviving flap areas. A scintigraphic evaluation was undertaken to analyze the surviving area. The flaps were evaluated histopathologically for vascularization, acute inflammation, and chronic inflammation.. The rate of surviving flap areas was observed to increase in parallel to the increase in the astaxanthin dose. Surviving flap areas and flap perfusion values were higher in group C compared with the control group and group A (P < 0.05). The values were also significantly higher in group B compared with control group (P < 0.05). All study groups were shown to have statistically significantly higher vascular density than the control group (P < 0.05), whereas lymphocyte and neutrophil densities were similar among all groups (P > 0.05). The photographic and scintigraphic evaluations for the viable area percentages of the flaps correlated with each other (rs = 0.913, P < 0.001).. Orally administered astaxanthin, if given at doses higher than 4 mg/kg, increases flap viability rates and vascularization and can be used as an adjunctive agent.

Topics: Administration, Oral; Animals; Graft Survival; Prospective Studies; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Skin Transplantation; Surgical Flaps; Xanthophylls

Activated inflammation and oxidant stress during cerebral ischemia reperfusion injury (IRI) lead to brain damage. Astaxanthin (ASX) is a type of carotenoid with a strong antioxidant effect.. The aim of this study was to investigate the role of ASX on brain IRI.. A total of 42 adult male Sprague-Dawley rats were divided into 3 groups as control (n=14) group, IRI (n=14) group and IRI + ASX (n=14) group. Cerebral ischemia was instituted by occluding middle cerebral artery for 120 minutes and subsequently, reperfusion was performed for 48 hours. Oxidant parameter levels and protein degradation products were evaluated. Hippocampal and cortex cell apoptosis, neuronal cell count, neurological deficit score were evaluated.. In the IRI group, oxidant parameter levels and protein degradation products in the tissue were increased compared to control group. However, these values were significantly decreased in the IRI + ASX group (p<0.05). There was a significant decrease in hippocampal and cortex cell apoptosis and a significant increase in the number of neuronal cells in the IRI + ASX group compared to the IRI group alone (p<0.05). The neurological deficit score which was significantly lower in the IRI group compared to the control group was found to be significantly improved in the IRI + ASX group (p<0.05).. Astaxanthin protects the brain from oxidative damage and reduces neuronal deficits due to IRI injury.

Topics: Animals; Brain; Disease Models, Animal; Hydrochloric Acid; Injections, Intraperitoneal; Male; Neuroprotective Agents; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Xanthophylls

Ischemia-reperfusion injury of the spinal cord (SCII) often leads to unalterable neurological deficits, which may be associated with apoptosis induced by oxidative stress and inflammation. Astaxanthin (AST) is a strong antioxidant and anti-inflammatory agent with multitarget neuroprotective effects. This study aimed to investigate the potential therapeutic effects of AST for SCII and the molecular mechanism.. Rat models of SCII with abdominal aortic occlusion for 40 min were carried out to investigate the effects of AST on the recovery of SCII. Tarlov's scores were used to assess the neuronal function; HE and TUNEL staining were used to observe the pathological morphology of lesions. Neuron oxidative stress and inflammation were measured using commercial detection kits. Flow cytometry was conducted to assess the mitochondrial swelling degree. Besides, Western blot assay was used to detect the expression of PI3K/Akt/GSK-3β pathway-related proteins, as well as NOX2 and NLRP3 proteins.. The results demonstrated that AST pretreatment promoted the hind limb motor function recovery and alleviated the pathological damage induced by SCII. Moreover, AST significantly enhanced the antioxidative stress response and attenuated mitochondrial swelling. However, AST pretreatment hardly inhibited the levels of proinflammatory cytokines after SCII. Most importantly, AST activated p-Akt and p-GSK-3β expression levels. Meanwhile, cotreatment with LY294002 (a PI3K inhibitor) was found to abolish the above protective effects observed with the AST pretreatment.. Overall, these results suggest that AST pretreatment not only mitigates pathological tissue damage but also effectively improves neural functional recovery following SCII, primarily by alleviating oxidative stress but not inhibiting inflammation. A possible underlying molecular mechanism of AST may be mainly attributed to the activation of PI3K/Akt/GSK-3β pathway.

Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Apoptosis; Glycogen Synthase Kinase 3 beta; Male; Mitochondrial Swelling; Neuroprotective Agents; Oxidative Stress; Phosphatidylinositol 3-Kinases; Proto-Oncogene Proteins c-akt; Rats, Sprague-Dawley; Reperfusion Injury; Signal Transduction; Spinal Cord Ischemia; Xanthophylls

Ischemic stroke is a leading cause of human death in present times. Two phases of pathological impact occur during an ischemic stroke, namely, ischemia and reperfusion. Both periods include individual characteristic effects on cell injury and apoptosis. Moreover, these conditions can cause severe cell defects and harm the blood-brain barrier (BBB). Also, the BBB components are the major targets in ischemia-reperfusion injury. The BBB owes its enhanced protective roles to capillary endothelial cells, which maintain BBB permeability. One of the nerve growth factor (NGF) receptors initiating cell signaling, once activated, is the p75 neurotrophin receptor (p75NTR). This receptor is involved in both the survival and apoptosis of neurons. Although many studies have attempted to explain the role of p75NTR in neurons, the mechanisms in endothelial cells remain unclear. Endothelial cells are the first cells to encounter p75NTR stimuli. In this study, we found the upregulated p75NTR expression and reductive expression of tight junction proteins after in vivo and in vitro ischemia-reperfusion injury. Moreover, astaxanthin (AXT), an antioxidant drug, was utilized and was found to reduce p75NTR expression and the number of apoptotic cells. This study verified that p75NTR plays a prominent role in endothelial cell death and provides a novel downstream target for AXT.

Topics: Animals; Animals, Newborn; Antioxidants; Blotting, Western; Brain; Cell Survival; Endothelial Cells; Immunochemistry; Immunohistochemistry; In Situ Nick-End Labeling; Male; Mice; Mice, Inbred C57BL; Receptor, Nerve Growth Factor; Reperfusion Injury; Xanthophylls

(1) Background: Reperfusion injury refers to the cell and tissue damage induced, when blood flow is restored after an ischemic period. While reperfusion reestablishes oxygen supply, it generates a high concentration of radicals, resulting in tissue dysfunction and damage. Here, we aimed to challenge and achieve the potential of a delivery system based on astaxanthin, a natural antioxidant, in attenuating the muscle damage in an animal model of femoral hind-limb ischemia and reperfusion. (2) Methods: The antioxidant capacity and non-toxicity of astaxanthin was validated before and after loading into a polysaccharide scaffold. The capacity of astaxanthin to compensate stress damages was also studied after ischemia induced by femoral artery clamping and followed by varied periods of reperfusion. (3) Results: Histological evaluation showed a positive labeling for CD68 and CD163 macrophage markers, indicating a remodeling process. In addition, higher levels of Nrf2 and NQO1 expression in the sham group compared to the antioxidant group could reflect a reduction of the oxidative damage after 15 days of reperfusion. Furthermore, non-significant differences were observed in non-heme iron deposition in both groups, reflecting a cell population susceptible to free radical damage. (4) Conclusions: Our results suggest that the in situ release of an antioxidant molecule could be effective in improving the antioxidant defenses of ischemia/reperfusion (I/R)-damaged muscles.

Topics: 3T3 Cells; Animals; Antioxidants; Cell Line; Disease Models, Animal; Macrophages; Male; Mice; Muscle, Skeletal; Oxidative Stress; Rats; Reperfusion Injury; Xanthophylls

Oxidative stress has been implicated in the pathogenesis of neurodegenerative disorders, such as vascular cognitive impairment (VCI). The present study was performed to investigate the potential neuroprotective effect of the antioxidant astaxanthin (ATX) in a mouse model of VCI. VCI was induced in male ICR mice by repeated occlusion of the bilateral common carotid artery, leading to repeated cerebral ischemia/reperfusion (IR) injury. After surgery, the mice received ATX or an equal volume of vehicle by daily intragastric administration for 28days. The results showed that ATX treatment ameliorated learning and memory deficits after repeated cerebral IR. ATX administration rescued the number of surviving pyramidal neurons in the CA1 and CA3 regions. The concentration of malondialdehyde was decreased, and the levels of reduced glutathione and superoxide dismutase in the hippocampus were increased. Electron microphotography revealed that damage to the ultrastructure of neurons was also reduced by ATX administration. In addition, the expression levels of Cytochrome C (Cyt C), cleaved Caspase-3 and Bax were lower and the expression of Bcl-2 was higher compared to control IR mice. Our findings demonstrate that ATX is able to suppresse learning and memory impairment caused by repeated cerebral IR and that this effect is associated with attenuation of oxidative stress.

Topics: Animals; Antioxidants; Apoptosis; Brain Ischemia; Cytochromes c; Dementia, Vascular; Disease Models, Animal; Glutathione; Hippocampus; Learning; Male; Malondialdehyde; Maze Learning; Memory Disorders; Mice; Mice, Inbred ICR; Neurons; Neuroprotective Agents; Oxidative Stress; Reperfusion; Reperfusion Injury; Superoxide Dismutase; Xanthophylls

Steatosis has a low tolerance against ischemia-reperfusion injury (IRI). To prevent IRI in the steatotic liver, we attempted to elucidate the protective effect of astaxanthin (ASTX) in the steatotic liver model by giving mice a methionine and choline-deficient high fat (MCDHF) diet. Levels of lipid peroxidation and apoptosis, the expression of inflammatory cytokines and heme oxygenase (HO)-1, in the liver were assessed. Reactive oxygen species (ROS), inflammatory cytokines, apoptosis-related proteins and members of the signaling pathway were also examined in isolated Kupffer cells and/or hepatocytes from the steatotic liver. ASTX decreased serum ALT and AST levels, the amount of TUNEL, F4/80, or 4HNE-positive cells and the mRNA levels of inflammatory cytokines in MCDHF mice by IRI. Moreover, HO-1 and HIF-1α, phosphorylation of Akt and mTOR expressions were increased by ASTX. The inflammatory cytokines produced by Kupffer, which were subjected to hypoxia and reoxygenation (HR), were inhibited by ASTX. Expressions of Bcl-2, HO-1 and Nrf2 in hepatocytes by HR were increased, whereas Caspases activation, Bax and phosphorylation of ERK, MAPK, and JNK were suppressed by ASTX. Pretreatment with ASTX has a protective effect and is a safe therapeutic treatment for IRI, including for liver transplantation of the steatotic liver.

Topics: Animals; Apoptosis; bcl-2-Associated X Protein; Cell Hypoxia; Cytoprotection; Gene Expression Regulation, Enzymologic; Heme Oxygenase-1; Hepatocytes; Hypoxia-Inducible Factor 1, alpha Subunit; Kupffer Cells; Liver; Male; Mice; Mice, Inbred C57BL; Non-alcoholic Fatty Liver Disease; Oxygen; Phosphorylation; Proto-Oncogene Proteins c-akt; Proto-Oncogene Proteins c-bcl-2; Reactive Oxygen Species; Reperfusion Injury; Signal Transduction; TOR Serine-Threonine Kinases; Xanthophylls

Astaxanthin exhibits various pharmacological activities, including anti-oxidative, anti-tumor, and anti-inflammatory effects, and is thought to exert a neuroprotective effect via these mechanisms. The purpose of this study was to investigate the protective effects of astaxanthin on neuronal cell death using a retinal ischemia/reperfusion model.. In vivo, retinal ischemia was induced by 5 h unilateral ligation of the pterygopalatine artery (PPA) and the external carotid artery (ECA) in ddY mice. Astaxanthin (100 mg/kg) was administered orally 1 h before induction of ischemia, immediately after reperfusion, at 6 or 12 h after reperfusion, and twice daily for the following 4 days. Histological analysis and an electroretinogram (ERG) were performed 5 days after ischemia/reperfusion. In vitro, cell death was induced in the RGC-5 (retinal precursor cells) by oxygen-glucose deprivation (OGD), and the rates of cell death and production of intracellular reactive oxygen species (ROS) were measured using nuclear staining and a ROS reactive reagent, CM-H. Histological studies revealed that astaxanthin significantly reduced retinal ischemic damage and ERG reduction. In in vitro studies, astaxanthin inhibited cell death and ROS production in a concentration-dependent manner.. Collectively, these results indicate that astaxanthin inhibits ischemia-induced retinal cell death via its antioxidant effect. Hence, astaxanthin might be effective in treating retinal ischemic pathologies.

Topics: Animals; Apoptosis; Cells, Cultured; Disease Models, Animal; Electroretinography; Fibrinolytic Agents; Ischemia; Male; Mice; Oxidative Stress; Reactive Oxygen Species; Reperfusion Injury; Retinal Diseases; Retinal Ganglion Cells; Xanthophylls

Astaxanthin (ATX) is a powerful antioxidant that occurs naturally in a wide variety of living organisms. Previous studies have shown that ATX has effects of eliminating oxygen free radicals and can protect organs from ischemia/reperfusion (IR) induced injury. The present study was designed to further investigate the protective effects of ATX on oxidative stress induced toxicity in tubular epithelial cells and on IR induced renal injury in mice. ATX, at a concentration of 250 nM, attenuated 100 μM H2O2-inudced viability decrease of tubular epithelial cells. In vivo, ATX preserved renal function 12 h or 24 h post IR. Pretreatment of ATX via oral gavage for 14 consecutive days prior to IR dramatically prevented IR induced histological damage 24 h post IR. Histological results showed that the pathohistological score, number of apoptotic cells, and the expression of α-smooth muscle actin were significantly decreased by pretreatment of ATX. In addition, oxidative stress and inflammation in kidney samples were significantly reduced by ATX 24 h post IR. Taken together, the current study suggests that pretreatment of ATX is effective in preserving renal function and histology via antioxidant activity.

Topics: Actins; Animals; Antioxidants; Apoptosis; Cell Survival; Cells, Cultured; Enzyme-Linked Immunosorbent Assay; Free Radicals; Humans; Hydrogen Peroxide; Inflammation; Kidney; Kidney Tubules; Male; Malondialdehyde; Mice; Mice, Inbred ICR; Muscle, Smooth; Oxidative Stress; Reperfusion Injury; Superoxide Dismutase; Xanthophylls

Hepatic ischemia reperfusion (IR) is an important issue in complex liver resection and liver transplantation. The aim of the present study was to determine the protective effect of astaxanthin (ASX), an antioxidant, on hepatic IR injury via the reactive oxygen species/mitogen-activated protein kinase (ROS/MAPK) pathway.. Mice were randomized into a sham, IR, ASX or IR + ASX group. The mice received ASX at different doses (30 mg/kg or 60 mg/kg) for 14 days. Serum and tissue samples at 2 h, 8 h and 24 h after abdominal surgery were collected to assess alanine aminotransferase (ALT), aspartate aminotransferase (AST), inflammation factors, ROS, and key proteins in the MAPK family.. ASX reduced the release of ROS and cytokines leading to inhibition of apoptosis and autophagy via down-regulation of the activated phosphorylation of related proteins in the MAPK family, such as P38 MAPK, JNK and ERK in this model of hepatic IR injury.. Apoptosis and autophagy caused by hepatic IR injury were inhibited by ASX following a reduction in the release of ROS and inflammatory cytokines, and the relationship between the two may be associated with the inactivation of the MAPK family.

Topics: Animals; Antioxidants; Apoptosis; Autophagy; Cytokines; Disease Models, Animal; Dose-Response Relationship, Drug; Down-Regulation; Inflammation Mediators; Liver Diseases; Male; Mice; Mice, Inbred BALB C; Mitogen-Activated Protein Kinases; Reactive Oxygen Species; Reperfusion Injury; Time Factors; Xanthophylls

Ischemia/reperfusion (I/R) injury must be overcome in order to succeed in small intestinal transplantation. Reactive oxygen species (ROS) are generated by I/R, and they induce lipid peroxidation which is one of the causes of mucosal lesion. We previously reported the protection effects of antioxidants to I/R injury in the in vitro study. In the present study, we examined the inhibitive effect of antioxidants on intestinal I/R injury in the in vivo study. Intestinal ischemia was induced in Wistar/ST rats using the spring scale and the surgical suture for 1 h, followed by reperfusion for 1 h. We used 4,5-dihydroxy-1,3-benzene-disulfonic acid (Tiron), astaxanthin (ATX) and epigallocatechin gallate (EGCG) as antioxidants. The inhibitive effects on mucosal lesion, opening of TJ and decrease in protein expression level of P-gp by in vivo intestinal I/R were admitted by three kinds of antioxidant. Tiron and EGCG inhibited P-gp function but ATX did not. Therefore, for the use of P-gp substrate like immunosuppressants after the intestinal transplantation, ATX, which does not inhibit P-gp is considered to be effective for intestinal I/R injury.

Topics: 1,2-Dihydroxybenzene-3,5-Disulfonic Acid Disodium Salt; Animals; Antioxidants; ATP Binding Cassette Transporter, Subfamily B, Member 1; Catechin; Dextrans; Fluorescein-5-isothiocyanate; Intestinal Absorption; Intestinal Mucosa; Intestines; Male; Rats; Rats, Wistar; Reperfusion Injury; Xanthophylls

This study investigated the effect of astaxanthin (ASX; 3,3-dihydroxybeta, beta-carotene-4,4-dione), a water-dispersible synthetic carotenoid, on liver ischemia-reperfusion (IR) injury. Astaxanthin (5 mg/kg/day) or olive oil was administered to rats via intragastric intubation for 14 consecutive days before the induction of hepatic IR. On the 15th day, blood vessels supplying the median and left lateral hepatic lobes were occluded with an arterial clamp for 60 min, followed by 60 min reperfusion. At the end of the experimental period, blood samples were obtained from the right ventricule to determine plasma alanine aminotransferase (ALT) and xanthine oxidase (XO) activities and animals were sacrificed to obtain samples of nonischemic and postischemic liver tissue. The effects of ASX on IR injury were evaluated by assessing hepatic ultrastructure via transmission electron microscopy and by histopathological scoring. Hepatic conversion of xanthine dehygrogenase (XDH) to XO, total GSH and protein carbonyl levels were also measured as markers of oxidative stress. Expression of NOS2 was determined by immunohistochemistry and Western blot analysis while nitrate/nitrite levels were measured via spectral analysis. Total histopathological scoring of cellular damage was significantly decreased in hepatic IR injury following ASX treatment. Electron microscopy of postischemic tissue demonstrated parenchymal cell damage, swelling of mitochondria, disarrangement of rough endoplasmatic reticulum which was also partially reduced by ASX treatment. Astaxanthine treatment significantly decreased hepatic conversion of XDH to XO and tissue protein carbonyl levels following IR injury. The current results suggest that the mechanisms of action by which ASX reduces IR damage may include antioxidant protection against oxidative injury.

Topics: Alanine Transaminase; Animals; Antioxidants; Disease Models, Animal; Glutathione; Liver; Male; Nitrates; Nitric Oxide Synthase Type II; Nitrites; Protein Carbonylation; Rats; Rats, Wistar; Reperfusion Injury; Xanthine Dehydrogenase; Xanthine Oxidase; Xanthophylls

Astaxanthin (AST) is a powerful antioxidant that occurs naturally in a wide variety of living organisms. Much experimental evidence has proved that AST has the function of eliminating oxygen free radicals and can protect organisms from oxidative damage. The present study was carried out to further investigate the neuroprotective effect of AST on oxidative stress induced toxicity in primary culture of cortical neurons and on focal cerebral ischemia-reperfusion induced brain damage in rats. AST, over a concentration range of 250-1000nM, attenuated 50μM H(2)O(2)-induced cell viability loss. 500nM AST pretreatment significantly inhibited H(2)O(2)-induced apoptosis measured by Hoechst 33342 staining and restored the mitochondrial membrane potential (MMP) measured by a fluorescent dye, Rhodamine 123. In vivo, AST prevented cerebral ischemic injury induced by 2h middle cerebral artery occlusion (MCAO) and 24h reperfusion in rats. Pretreatment of AST intragastrically twice at 5h and 1h prior to ischemia dramatically diminished infarct volume and improved neurological deficit in a dose-dependent manner. Nissl staining showed that the neuronal injury was significantly improved by pretreatment of AST at 80mg/kg. Taken together, these results suggest that pretreatment with AST exhibits noticeable neuroprotection against brain damage induced by ischemia-reperfusion and the antioxidant activity of AST maybe partly responsible for it.

Topics: Animals; Apoptosis; Behavior, Animal; Cell Death; Cells, Cultured; Coloring Agents; Fluorescent Dyes; Hydrogen Peroxide; Infarction, Middle Cerebral Artery; Ischemic Attack, Transient; Male; Matrix Metalloproteinases; Neurons; Neuroprotective Agents; Oxidants; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Rhodamine 123; Tetrazolium Salts; Thiazoles; Xanthophylls

We previously established a in vitro system for assessing early ischemia/reperfusion injury using monolayers of human intestinal epithelial cell line Caco-2, in which lipid peroxidation caused by tertiary-butylhydroperoxide (t-BuOOH), a lipid peroxidation inducer, acts as a trigger of the injury. By now, we have shown that superoxide anion participates in the opening of tight junctions (TJ) induced by reoxygenation following the induction of lipid peroxidation by t-BuOOH at a low concentration. The present objectives are to elucidate the dysfunction of P-glycoprotein (P-gp) in addition to the opening of TJ by t-BuOOH at a high concentration condition using rhodamine123 (Rho123) as a P-gp substrate and cyclosporine A (CyA) as a P-gp inhibitor. Also, we compared the inhibition effect of lutein and other compounds such as biliverdin as a radical scavenger on the opening of TJ and the dysfunction of P-gp. t-BuOOH at a high concentration increased the permeability of Rho123 in the apical to basal direction and decreased basal to apical direction when compared with control conditions. t-BuOOH at a high concentration showed no significant difference between directional transport of Rho123 and no inhibition was observed in the permeability of both directions by CyA. The staining intensity of Western blot was decreased by t-BuOOH at a high concentration. Although lutein and the other compounds had recovery effects on the opening of TJ and P-gp dysfunction induced by t-BuOOH, lutein is more advantageous than other compounds since it has effective effects at the lower concentration. In conclusion, the barrier dysfunction such as the inhibition of P-gp in addition to the opening of TJ was induced by t-BuOOH at a high concentration condition. The above two barrier dysfunctions was ameliorated by antioxidant such as lutein and biliverdin.

Topics: 1,2-Dihydroxybenzene-3,5-Disulfonic Acid Disodium Salt; Antioxidants; ATP Binding Cassette Transporter, Subfamily B, Member 1; Biliverdine; Blotting, Western; Caco-2 Cells; Cell Membrane Permeability; Dose-Response Relationship, Drug; Epithelial Cells; Fluorescent Dyes; Humans; Indicators and Reagents; Intestinal Mucosa; Intestines; Lipid Peroxidation; Lutein; Reperfusion Injury; Rhodamine 123; tert-Butylhydroperoxide; Vitamin E; Xanthophylls