Resveratrol attenuates oxidative stress and histological alterations induced by liver ischemia/reperfusion in rats

AIM: To investigate the effects of resveratrol on liver ischemia/reperfusion (I/R) injury in rats

Iloprost, a prostacyclin (PGI2) analogue, reduces liver injury in hepatic ischemiareperfusion in rats Iloprost, um análogo da prostaciclina (PGI2), reduz danos da isquemia/reperfusão hepática em ratos

PURPOSE: To evaluate the effects of iloprost a prostacyclin analogue on the hepatic IR injury in rats. METHODS: Forty male Sprague-Dawley rats (250-300 g) were divided into four groups each containing 10 rats;(1)- controls: data from unmanipulated animals; (2) sham group: rats subjected to the surgical procedure, except for liver I/R, and given saline; (3) I/R group: rats that underwent liver ischemia for 45 min followed by reperfusion for 45 min; (4) IR/ Iloprost group: rats pretreated with iloprost (10 µg kg-1, i.v). Liver tissues were taken to determine SOD, CAT, GSH, and MDA levels and for biochemical and histological evaluation. RESULTS: The plasma ALT and AST levels were increased in group 3 than in group 4. MDA values and the liver injury score decreased, while the SOD, CAT, and GSH values increased in group 4 compared to group 3. In group 3, hepatocytes were swollen with marked vacuolization. In group 4, there were regular sinusoidal structures with normal morphology without any signs of congestion. CONCLUSION: We demonstrated hepatoprotective effects of iloprost against severe ischemia and reperfusion injury in rat liver.<br>OBJETIVO: Avaliar os efeitos do iloprost, um análogo da prostaciclina nos danos causados ao fígado de ratos pela lesão de IR. MÉTODOS: Quarenta ratos machos Sprague-Dawley (250-300 g) foram distribuídos em quatro grupos de dez; - (1) grupo de controle: dados de animais não manipulados; (2) grupo "sham": ratos que sofreram intervenção cirúrgica sem I/R, aos quais foram administrados solução salina; (3) grupo I/R; animais que foram submetidos à isquemia por 45 minutos seguida de reperfusão por 45 minutos; (4) grupo I R/Iloprost: ratos previamente tratados com Iloprost ( 10µ kg-1, i.v). Tecidos hepáticos foram retirados para determinar os níveis de SOD, CAT, GSH, e MDA e para avaliação bioquímica e histológica. RESULTADOS: Os níveis de plasma ALT e AST aumentaram no grupo 3 mais do que no grupo 4. Os valores de MDA e o índice de lesões hepáticas diminuíram, enquanto os valores de SOD, CAT e GSH aumentaram no grupo 4, em comparação com o grupo3. No grupo 3, os hepatócitos se apresentaram edemaciados, e vacuolizados. No grupo 4, havia estruturas sinusoidais regulares, apresentando morfologia normal, sem sinais de congestão. CONCLUSÃO: Demonstramos os efeitos hepato-protetores do Iloprost contra a isquemia grave e o dano de reperfusão no fígado de ratos

The Changes in Status of Antioxidant Defence System on Temporary Cerebral Ischemia and the Protective Effect of Vitamin E and C

Time-dependent changes in antioxidant defence system and the effect ofvitamin C and E supplementation on temporary cerebral ischemia wasinvestigated in this study. This study was performed in 140 male Wistaralbino rats weighting 300-400g. Before 30 minutes cerebral ischemiavitamin E (α-tocopherol) 10 mg/kg/day and vitamin C 30 mg/kg/day wereapplied intraperitoneally for a week period. Animals were sacrifiedfollowing 24 h and 72 h ischemia and the brain was removed as quick aspossible. Brain water content, süperoxide dismutase (SOD) ) and catalase(CAT) activities and the level of nonenzymatic antioxidant, reduced vitaminC and α-tocopherol levels were measured. Moreover the level ofmalondialdehyde (MDA) as an indicator of lipid peroxidation wasdetermined. At 24 h of reperfusion superoxide dismutase (SOD) andcatalase (CAT) activities, vitamin C and E level decreased significantly inischemic brain area (p<0.05, p<0.05, p<0.01 and p<0.01 respectively). After72 h of reperfusion SOD and CAT activities surpassed the pre-ischemiclevel (p<0.01 and p<0.05 respectively). The level of vitamin C and Eincreased significantly at 72 hours after ischemia but, did not reach preischemiclevels (p<0.01 and p<0.01 respectively). Administration of vitaminC and E a week before cerebral ischemia prevented the decrease in SODand CAT activities after 24 hours of reperfusion (p<0.01 and p<0.01respectively). Furthermore, the increase in ischemia induced lipidperoxidation and cerebral edema were decreased significantly byadministration of these vitamins (p<0.01 and p<0.01 respectively). Invitamins applied groups, increase in SOD and catalase activities at 72 hoursafter ischemia was similar to control. The results indicated that there isnegative correlation between vitamin C or E level and lipid peroxidation orcerebral edema. Similar relationship was found between SOD or CATactivitiy and lipid peroxidation or cerebral edama.Temporary cerebral ischemia changed the state of anti-oxidant defencesystem and these changes were significantly prevented by treatment with Cand E vitamins before ischemia

Influence of coumarin and some coumarin derivatives on serum lipid profiles in carbontetrachloride-exposed rats

In the present study, coumarin and some coumarin derivatives (esculetin, scoparone, and 4-methylumbelliferone) were investigated for their lipid-lowering effect in rats. Male Sprague-Dawley rats (150-200 g) were divided into six groups and each group comprised of five rats. Hepatic injury-dependent hyperlipidemia was induced by carbon tetrachloride (CCl4, 1.25 ml/kg). Coumarin and coumarin derivatives esculetin (35 mg/kg), scoparone (35 mg/kg), 4-methylumbelliferone (35 mg/kg), or coumarin (30 mg/kg) were administered to experimental groups at 12-h intervals. Animals received the derivatives esculetin, scoparone or 4-methylumbelliferone prior to the administration of a single toxic dose of CCl4. Serum total cholesterol (TC), triglyceride (TG), very low-density lipoprotein cholesterol (VLDL-C), and low-density lipoprotein cholesterol (LDL-C) levels significantly increased in CCl4-treated group (p < 0.05, p < 0.01, p < 0.01, and p < 0.05, respectively), while levels of serum high-density lipoprotein cholesterol (HDL-C) decreased (p < 0.01). 4-Methylumbelliferone had no recovery effects on serum TC levels, however, significantly prevented CCl4-induced hyperlipidemia by reducing TG and VLDL-C levels (p < 0.05 and p < 0.05, respectively). In addition, coumarin had no recovery effect on any of the serum lipid parameters against CCl4-induced hyperlipidemia. Among the coumarin derivatives only esculetin and scoparone significantly prevented serum HDL-C in CCl4-induced dyslipidemia. The results from this study indicate that the chemical structure of coumarins plays an important role on the regulation of serum lipid profiles