Cardioprotective effect of aqueous extract of Embelia ribes Burm fruits against isoproterenol-induced myocardial infarction in albino rats.

In the present study, cardioprotective effect of aqueous extract of fruits of Embelia ribes Burm (ER) was evaluated in a rat model having acute myocardial infarction, induced by isoproterenol (5.25 and 8.5 mg/kg, sc, for two consecutive days). Aqueous ER extract (100 mg/kg) pretreatment orally for 40 days in isoproterenol (ISO)-treated rats significantly decreased the heart rate, systolic blood pressure, increased levels of serum lactate dehydrogenase, serum creatine kinase and myocardial lipid peroxides and significantly increased the myocardial endogenous antioxidants (glutathione, superoxide dismutase and catalase) levels. The results of biochemical observations in serum and heart tissues were supplemented by histopathological examination of rat's heart sections to confirm the myocardial injury. The results were comparable to that of gliclazide treated group. The present results provide evidence for the first time, that aqueous ER extract pretreatment ameliorated myocardial injury and enhanced the antioxidant defense against ISO-induced myocardial infarction in rats and exhibited cardioprotective property.

Antihyperglycaemic activity of aqueous extract of Embelia ribes Burm in streptozotocin-induced diabetic rats.

Forty days of orally feeding the aqueous E. ribes extract (100 and 200 mg/kg) to streptozotocin (40 mg/kg, iv, single dose) induced diabetic rats produced significant decrease in heart rate, systolic blood pressure, blood glucose, blood glycosylated hemoglobin, serum lactate dehydrogenase, creatine kinase and increase in blood glutathione levels as compared to pathogenic diabetic rats. Further, the extract significantly decreased the levels of pancreatic lipid peroxides and increased the levels of pancreatic superoxide dismutase, catalase and glutathione. The results suggest that aqueous E. ribes extract exhibits a significant blood glucose and blood pressure lowering potential. Further, it enhances endogenous antioxidant defense against free radicals produced under hyperglycaemic conditions, thereby, seemingly protects the pancreatic beta-cells against loss in streptozotocin induced diabetic rats.

Protective effect of Embelia ribes Burm on methionine-induced hyperhomocysteinemia and oxidative stress in rat brain.

The present study was aimed to find out the protective effect of ethanolic extract of E. ribes fruits on homocysteine, lactate dehydrogenase (LDH) and lipid profile in serum, lipid peroxidation (LPO) and non-enzymatic antioxidant glutathione (GSH) levels in brain homogenates and histopathological examination of brain tissue in methionine (1 g/kg body weight, orally for 30 days) induced hyperhomocysteinemic rats. A significant increase in homocysteine, LDH, total cholesterol, triglycerides, low density lipoprotein (LDL-C) and very low density lipoprotein (VLDL-C) levels was observed in serum. Increased LPO levels in brain homogenates with reduced serum high density lipoprotein (HDL-C) levels and decreased GSH content were other salient features observed in methionine treated pathogenic control rats. Administration of ethanolic E. ribes extract (100 mg/kg body weight, orally) for 30 days to methionine-induced hyperhomocysteinemic rats produced a significant decrease in the levels of homocysteine, LDH, total cholesterol, triglycerides, LDL-C, VLDL-C in serum and LPO levels in brain homogenates with significant increase in serum HDL-C levels and GSH content in brain homogenates, when compared with pathogenic control rats. Biochemical observations were further substantiated with histological examination of brain. Degenerative changes of neuronal cells in methionine treated rats were minimized to near normal morphology by ethanolic E. ribes extract administration as evident by histopathological examination. The results provide clear evidence for the first time, that ethanolic E. ribes extract treatment enhances the antioxidant defense against methionine-induced hyperhomocysteinemia and oxidative stress in brain.

Modulatory effect of curcumin on methionine-induced hyperlipidemia and hyperhomocysteinemia in albino rats.

The present study was designed to investigate the antioxidant effect of curcumin on methionine-induced hyperlipidemia and hyperhomocysteinemia in Wistar rats (200-250 g) of either sex. The vehicle control rats were treated with 1% Tween 80 in normal saline (2 ml/kg, po) for 30 days. Hyperlipidemia and hyperhomocysteinemia was induced by methionine administration (1 g/kg, po) for 30 days. A significant increase in total cholesterol, triglycerides, low density lipoprotein cholesterol (LDL-C) and homocysteine levels in serum and thiobarbituric acid reactive substances (TBARS) levels in heart homogenates were observed with a concomitant decrease in serum high density lipoprotein (HDL-C) levels in pathogenic control (i.e. group II) rats, as compared to vehicle control (i.e. group I) rats. Further, curcumin (200 mg/kg, p.o.) treatment in methionine treated rats for 30 days significantly decreased the total cholesterol, triglycerides, LDL-C and homocysteine levels in serum and TBARS levels in heart homogenates and increased serum HDL-C levels, as compared to pathogenic control (i.e. group II) rats. The results of biochemical observations were supplemented by histopathological examination of rat's aortic section. The results of test drug were comparable to that obtained with folic acid (100 mg/kg, p.o.). The results suggest that curcumin has significant antihyperlipidemic and antihyperhomocysteinemic effect against methionine-induced hyperlipidemia and hyperhomocysteinemia in rats.

Ethanolic Zingiber officinale R. extract pretreatment alleviates isoproterenol-induced oxidative myocardial necrosis in rats.

Ethanolic Z. officinale (ZO) extract (200 mg/kg) pretreatment for 20 days in isoproterenol (ISO)-treated rats significantly increased the levels of endogenous myocardial antioxidants (catalase, superoxide dismutase and tissue glutathione), decreased the levels of serum marker enzymes (lactate dehydrogenase, creatine kinase, aspartate transaminase and alanine transaminase) and increased myocardial lipid peroxides. Histological examination of rat's heart section confirmed myocardial injury with ISO administration and near normal pattern with ethanolic ZO extract pretreatment. The results of the present study, for the first time, provide clear evidence that the ethanolic ZO extract pretreatment enhances the antioxidant defense against ISO-induced oxidative myocardial injury in rats and exhibit cardioprotective property.

Protective effect of aqueous extract of Embelia ribes Burm fruits in middle cerebral artery occlusion-induced focal cerebral ischemia in rats.

OBJECTIVE: The present study was carried out to evaluate the neuroprotective effect of the aqueous extract of Embelia ribes, in focal ischemic brain. MATERIALS AND METHODS: Adult male Wistar albino rats were fed with the aqueous extract of Embelia ribes (100 and 200 mg/kg, p.o.) for 30 days. After 30 days of feeding, all the animals were anaesthetized with chloral hydrate (400 mg/kg, i.p.). The right middle cerebral artery was occluded with a 4-0 suture for 2 h. The suture was removed after 2 h, to allow reperfusion injury. The animals were used for grip strength measurement, biochemical estimation in serum and brain tissue (hippocampus and frontal cortex) and cerebral infarct size measurement. RESULTS: In the ischemic group, a significant (P < 0.01) alteration in the markers of oxidative damage (thiobarbituric acid reactive substances (TBARS); reduced glutathione (GSH); glutathione peroxidase (GPx); glutathione reductase (GR); and, glutathione-S-transferase (GST)) was observed in the hippocampus and frontal cortex, as compared to sham operated rats. We observed that the animals treated with the aqueous extract of Embelia ribes had a significant (P < 0.01) increase in the poststroke grip strength activity. Further, supplementation with aqueous extract of Embelia ribes reversed the levels/activities of the above mentioned biochemical parameters significantly (P< 0.01) and also resulted in decreased cerebral infarct area, as compared to the ischemic group. CONCLUSION: The results of our study, for the first time, provide clear evidence that aqueous extract of Embelia ribes pretreatment ameliorates cerebral ischemia/reperfusion injury and enhances the antioxidant defense against middle cerebral artery occlusion-induced cerebral infarction in rats; it exhibits neuroprotective property.

Effect of rosuvastatin on methionine-induced hyperhomocysteinaemia and haematological changes in rats.

The present study was designed to investigate the protective effect of rosuvastatin on methionine-induced hyperhomocysteinaemia and haematological changes in albino rats. Methionine (1 g/kg, orally) administration to pathogenic control rats (i.e. group II) for 30 days significantly (P < 0.01) increased the levels of homocysteine, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), very low-density lipoprotein cholesterol (VLDL-C) and triglycerides (TGs) and decreased the levels of high-density lipoprotein cholesterol (HDL-C) in serum. Haematological observations of the peripheral blood smears of pathogenic rats (i.e. group II) fed with methionine also showed crenation of red blood cells cell membrane and significant (P < 0.01) increase in total leucocyte count, differential leucocyte count and platelet counts with significant (P < 0.01) decrease in the mean haemoglobin levels as compared to vehicle control rats (group I). Administration of rosuvastatin (0.5 mg/kg/day, orally) to hyperhomocysteinaemic rats for 30 days significantly (P < 0.01) decreased the levels of homocysteine, TC, TGs, LDL-C, VLDL-C and increased the levels of HDL-C in serum. The present results provide clear evidence that oral treatment with rosuvastatin produces homocysteine and lipid lowering activity and also reversal of haematological changes induced by methionine in rats.

The effect of aqueous extract of Embelia ribes Burm on serum homocysteine, lipids and oxidative enzymes in methionine induced hyperhomocysteinemia.

OBJECTIVE: The present study was designed to evaluate the effect of the aqueous extract of Embelia ribes Burm fruits on methionine-induced hyperhomocysteinemia, hyperlipidemia and oxidative stress in albino rats. MATERIALS AND METHODS: Adult male Wistar albino rats were fed with the aqueous extract of Embelia ribes (100 and 200 mg/kg, p.o.) for 30 days. Hyperhomocysteinemia was induced by methionine treatment (1 g/kg, p.o.) for 30 days and folic acid (100 mg/kg, p.o.) was used as a standard drug. The animals were evaluated for various biochemical parameters in serum and brain homogenates, followed by histopathological studies at the end of the study. RESULTS: Administration of methionine (1 g/kg, p.o.) for 30 days to vehicle control rats produced significant increase (P < 0.01) in homocysteine, lactate dehydrogenase (LDH), total cholesterol, triglycerides, low density lipoprotein (LDL-C), very low density lipoprotein (VLDL-C) levels in serum and lipid peroxides (LPO) levels in brain homogenates, with reduction in high density lipoprotein (HDL-C) levels in serum, and glutathione (GSH) content in brain homogenates, as compared to vehicle control rats. Administration of the aqueous extract of Embelia ribes (100 and 200 mg/kg, p.o.) for 30 days, to hyperhomocysteinemic rats, significantly (P < 0.01) decreased the levels of homocysteine, LDH, total cholesterol, triglycerides, LDL-C and VLDL-C and increased the HDL-C levels in serum. In addition, a significant (P < 0.01) decrease in LPO levels with increase in GSH content was observed in hyperhomocysteinemic rats treated with the aqueous extract of Embelia ribes. The results were comparable to those obtained with folic acid, a standard antihyperhomocysteinemic drug. CONCLUSION: The present results provide clear evidence that the aqueous extract of Embelia ribes treatment enhances the antioxidant defense against methionine-induced hyperhomocysteinemia, hyperlipidemia and oxidative stress in brain.