Antidiabetic and antioxidant effects of <Emphasis Type="Italic">Picrorhiza kurrooa</Emphasis> rhizome extracts in diabetic rats

Picrorhiza kurrooa is mentioned in Ayurveda for the treatment of many disorders, but it has not been subjected to systematic scientific investigations to assess its antidiabetic effect. The oral administration of aqueous and methanol extracts of P. kurrooa rhizomes (250 and 500 mg / kg body weight / day) for 15 days significantly reduced blood glucose, glycosylated haemoglobin and increased total hemoglobin, plasma insulin in alloxan-induced diabetes in albino rats. The treatment also showed significant correction in the level of nitric oxide radicals, superoxide radicals, peroxynitrite radical, lipid peroxidation, glutathione, glutathione reductase, glutathione-S-transferase, glutathione peroxidase, superoxide dismutase and catalase in the pancreas of alloxan diabetic rats.     

Hypoglycaemic, hypolipidemic and antioxidant properties of tulsi (Ocimum sanctum linn) on streptozotocin induced diabetes in rats

Effect of oral administration of 200 mg/Kg body weight of the aqueous extract ofOcimum sanctum (Tulsi) mixed with diet for eight weeks to diabetic (streptozotocin induced) rats was studied. There was significant reduction in fasting blood glucose, serum lipid profile, lipid peroxidation products, (LPO) and improvement in glucose tolerance. The aqueous extract also decreased LPO formation (thiobarbituric acid reactive substances TBARS) and increased antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), glutathione transferase (GT) and one antioxidant reduced glutathione (GSH) in plasma and rat liver, lung, kidney and brain. The decrease in TBARS and increase in GSH, SOD, CAT, GPX, and GT clearly shows the antioxidant property ofOcimum sanctum.     

Effect ofOcimum sanctum (Tulsi) and vitamin E on biochemical parameters and retinopathy in streptozotocin induced diabetic rats

This study was carried out to see the effect of the aqueous extract ofOcitum sanctum Linn (Tulsi) with Vitamin E on biochemical parameters and retinopathy in the streptozotocin-induced diabetic albino male rats. Adult albino male rats weighing 150–200 gm were made diabetic by intraperitoneal injection of streptozotocin in the dose 60 mg/kg in citrate buffer (pH 6.3). The diabetic animals were left for one month to develop retinopathy. Biochemical parameters like plasma glucose, oral glucose tolerance and glycosylated hemoglobin HbA_1c, were measured along with lipid profile, and enzymes like glutathione peroxidase (GPX), lipid peroxidase (LPO), superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST) in normal, untreated diabetic rats and diabetic rats treated withOcimum sanctum L extracts and vitamin E. Fluorescein angiography test was done for assessing retinopathy. Results on biochemical parameters were analyzed statistically by using ANOVA followed by Dunnet's ‘t’-test. A p-value of <0.05 was considered as significant. Evaluation of biochemical profile in treated groups showed statistically significant reduction in plasma levels of glucose, HbA_1c, lipid profile and LPO, and elevation of GPX, SOD, CAT and GST. Treatment of the diabetic animals withOcimum sanctum and Vitamin E, alone and in combination for 16 weeks showed reversal of most of the parameters studied including plasma glucose levels. Angiography showed improvement in retinal changes following combined antidiabetic treatment.     

Lipid peroxidation and the levels of antioxidant enzymes in coronary artery disease

Coronary Artery Disease is the major cause of mortality and morbidity worldwide. Traditional risk factors account for only half of the morbidity and mortality from coronary artery disease. There is substantial evidence that oxidative stress plays the major role in the atherosclerotic process. The present study was undertaken to evaluate the level of lipid peroxidation (by measuring malondialdehyde) and antioxidant enzymes (ceruloplasmin, glutathione, superoxide dismutase) in coronary artery disease. Serum malondialdehyde levels and serum ceruloplasmin levels were significantly raised in all the subgroups of study group as compared to control group (p<0.001). Whole blood glutathione levels and hemolysate superoxide dismutase activity was significantly decreased in all the subgroups of study group as compared to control group (p<0.001). Above results suggests that the patients of coronary artery disease show increased oxidative stress and decreased levels of antioxidant enzymes. So it is recommended that the management protocol for coronary artery disease patients should include antioxidant supplementation along with simultaneous lowering of lipid peroxidation.     

Antioxidant status in patients with acute myocardial infarction

Free radicals play an important role in the pathogenesis of tissue damage in many clinical disorders, including atherosclerosis. Antioxidants protect the body from damage caused by free radicals. In this study we investigated oxidative stress, antioxidants and inflammatory molecules in patients with acute myocardial infarction. This study has been carried out on 106 patients with acute myocardial infarction, (89 men and 17 females). The control group consisted of 50 healthy, age-matched subjects (40 men and 10 females). Levels of Glucose, lipid profile, glutathione reduced, glutathione peroxidase, Superoxide dismutase, Glycosylated hemoglobin, fibrinogen, vitamin C, vitamin E, malondialdehyde, ceruloplasmin, adenosine deaminase, lysozyme and sialic acid were measured. Malondialdehyde and ceruloplasmin levels were significantly high and antioxidants such as vitamin C, vitamin E, glutathione reduced, glutathione peroxidase and superoxide dismutase were significantly decreased in diabetic and non-diabetic AMI patients as compared with control (p<0.001). Inflammatory markers showed significant rise in diabetic patients as compared with controls. Our results clearly show increased inflammation and oxidative stress in patients with acute myocardial infarction. Depression of antioxidant system in these patients confirms this conclusion.     

Antioxidant status in neonatal jaundice before and after phototherapy

Phototherapy has been related to increased oxidative stress and lipid peroxidation. In the present study, thirty full term jaundiced neonates with appropriate weight were analyzed before and after completion of phototherapy for malondialdehyde (MDA), reduced glutathione (GSH), total thiols, vitamin C and superoxide dismutase (SOD) levels in hemolysate and albumin levels in plasma. These parameters were analyzed in cord blood samples of 20 healthy neonates as control. It was observed that levels of MDA were elevated significantly (p<0.001) in patients as compared to controls and that the levels increased significantly after phototherapy (p<0.001). Levels of SOD were also found to be increased significantly as compared to controls and the levels rose after phototherapy (p<0.001). On the other hand, the levels of non-enzymatic antioxidants such as GSH, total thiols and vitamin C were significantly low (p<0.001) as compared to controls and the levels decreased significantly after phototherapy (p<0.001). The plasma albumin levels also were found to be decreased significantly after phototherapy (p<0.01). Therefore, phototherapy increases oxidative stress and should be used with care.     

Preliminary studies on the hypoglycemic effect of <Emphasis Type="Italic">Peganum harmala</Emphasis> L. Seeds ethanol extract on normal and streptozotocin induced diabetic rats

Peganum harmala L. (Zygophyllaceae) is a traditional medicine used for the treatment of variety of human ailments, including antidepression, hallucination, antileishmaniasis etc. We report for first time the hypoglycemic activity of the ethanolic extract of this plant at two dose levels of 150 and 250mg/kg bw in sucrose challenged normal as well as in rats with streptozotocin induced diabetes. The oral administration of ethanolic extract causes maximum fall of blood glucose level to 22.9% (p<0.05) and 29.4% (p<0.01) respectively with the two doses in normal and 30.3% (p<0.01) and 48.4% (p<0.001) in diabetic rats. The standard drug metformin treated group showed 28.0% (p<0.01) and 45.5% (p<0.001) respectively in normal and diabetic rats. The above results show that the ethanolic extract of P. harmala is as effective as metformin in reducing the blood glucose levels of normoglycemic and streptozotocin-induced diabetic rats.     

Anti-Oxidative Effect of <Emphasis Type="Italic">Cassia auriculata</Emphasis> on Streptozotocin Induced Diabetic Rats

The anti oxidative effect of administration of 100 mg/kg bw and 200 mg/kg bw of the flower powder of Cassia auriculata (CFP) for 45 days to normoglycemic and diabetic rats (streptozotocin induced) was studied. Anti oxidative effect was not observed in normoglycemic rats in the experiment. There was significant (P > 0.05) increase in the level of Thio Barbituric Acid Reactive Substances (TBARS), hydroperoxide and conjugated dienes and significant (P > 0.05) decrease in the catalase, superoxide dismutase and glutathione peroxidase activities and in the level of ascorbic acid, vitamin E and reduced glutathione in diabetic rats. The flower powder of Cassia auriculata significantly (P > 0.05) decreased the TBARS, hydroperoxide and conjugated dienes and increased the antioxidant enzymes (catalase, superoxide dismutase and glutathione peroxidase) and non enzymic anti oxidants (ascorbic acid, vitamin E and reduced glutathione). The antioxidatve effect of 200 mg/kg bw CFP was significantly (P > 0.05) better than 100 mg/kg bw CFP and the reference drugs (tolbutamide and metformin). The mode of action of CFP remains to be elicited.     

Lipid peroxidation and antioxidant vitamins in urolithasis

The present, study was conducted to determine the level of malondialdehyde (MDA) as an index of free radial induced lipid peroxidation and antioxidant vitamins-vitamins A, vitamin C and vitamin E in 75 confirmed cases of urolithiasis. Significantly high level of MDA (p<0.001) with significantly low levels of vitamin E (p<0.001) and vitamin A (p<0.001) with no significant decrease in vitamin C (p>0.05) were observed in the plasma of urolithiasis cases as compared to normal controls. In conclusion, it appears that a role of lipid peroxidation and oxidative function exists in the pathogenesis of urolithiasis. But, the exact mechanism how this occurs remains to be elucidated.     

Protective Effect of Emblica officinalis Against Alcohol-Induced Hepatic Injury by Ameliorating Oxidative Stress in Rats

The effect of Emblica officinalis fruit extract (EFE) against alcohol-induced hepatic damage in rats was investigated in the present study. In vitro studies showed that EFE possesses antioxidant as well nitric oxide (NO) scavenging activity. In vivo administration of alcohol (5 g/kg b.wt/day) for 60 days resulted increased liver lipid peroxidation, protein carbonyls, nitrite plus nitrate levels. Alcohol administration also significantly lowers the activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione S-transferase and reduced glutathione as compared with control rats. Administration of EFE (250 mg/kg body weight) to alcoholic rats significantly brought the plasma enzymes towards near normal level and also significantly reduced the levels of lipid peroxidation, protein carbonyls and restored the enzymic and non-enzymatic antioxidants level. This observation was supplemented by histopathological examination in liver. Our data indicate that the tannoid, flavonoid and NO scavenging compounds present in EFE may offer protection against free radical mediated oxidative stress in rat hepatocytes of animals with alcohol-induced liver injury.     

Antidiabetic and ameliorative potential of Ficus bengalensis bark extract in streptozotocin induced diabetic rats

The aim of the present study was to evaluate the antidiabetic and ameliorative potential of aqueous extract of Ficus bengalensis bark in streptozotocin induced diabetic rats. The effect of oral administration of aqueous extract of F. bengalensis bark on blood glucose, serum electrolytes, serum glycolytic enzymes, liver microsomal protein, hepatic cytochrome P-450 dependent monooxygenase enzymes and lipid peroxidation in liver and kidney of streptozotocin -induced diabetic rats was studied. Oral administration of Ficus bengalensis to fed, fasted and glucose loaded diabetic rats significantly [F > 0.05 (ANOVA) and P< 0.05 (DMRT)] decreased the blood glucose level at 5 hrs and restored the levels of serum electrolytes, glycolytic enzymes and hepatic cytochrome P-450 dependent enzyme systems and decreased the formation of liver and kidney lipid peroxides at the end of 12 weeks. Further, the aqueous extract of Ficus bengalensis at a dose of 500mg/kg/day exhibits significant antidiabetic and ameliorative activity as evidenced by histological studies in normal and Ficus bengalensis treated streptozotocin induced diabetic rats. On the basis of our findings, it could be used as an antidiabetic and ameliorative agent for better management of diabetes mellitus.     

Plasma MDA and antioxidant vitamins in diabetic retinopathy

Hyperglycemia and dyslipidemia in diabetes mellitus induce increased lipid peroxidation and peroxyl radical formation, an important mechanism in genesis of microangiopathy. We took up a study on oxidative stress, measured by plasma MDA and antioxidant vitamin status in type − 2 DM patients with and without retinopathy and compared them with a control non-diabetic group. Lipid peroxidation marker MDA was significantly elevated (p < 0.001) in both the diabetic groups whereas, serum vitamin E and vitamin C registered a significant fall (p<0.001) as compared to controls. Our correlation study revealed a significant positive association between plasma MDA with both fasting and 2hr post prandial plasma glucose (r=0.81, p < 0.001, r=0.92, p <0.001) suggesting the role of hyperglycemia in free radical production. Plasma MDA also depicted significant positive relation (p< 0.001) with all lipid parameters except serum HDLc pointing the role of dyslipidemia towards lipid peroxidation. Plasma MDA level was also found to be negatively correlated with both the vitamins (p<0.001, p<0.001) in the study group explaining their protective consumption in the oxidative process prevailing in diabetic retinopathy.     

An opium alkaloid-papaverine ameliorates ethanol-induced hepatotoxicity: Diminution of oxidative stress

In this communication, we show the modulatory potential of papaverine, an opium alkaloid and a well known vasodilator agent on the ethanol-induced hepatic oxidative stress in male Wistar rats. Ethanol treatment (50% v/v) enhanced lipid peroxidation significantly accompanied by a decline in the activities of glutathione peroxidase (G-Px), glutathione reductase (GR) and depletion in levels of hepatic glutathione (GSH). Ethanol administration increased hepatic glutathione-s-transferases (GST). Enhanced lipid peroxidation induced by ethanol was significantly reduced when papverine was coadministered (P<0.05). In addition, the depleted levels of glutathione and inhibited activities of G-Px and GR recovered significantly (P<0.05) levelling off to control values on co-exposure. Papaverine (200 mg/kg bw) effectively antagonised the ethanol-induced lipid peroxidation and impaired glutathione levels and glutathione dependent enzyme systems. Our results suggest that papaverine is an effective chemopreventive agent in the liver and may suppress the ethanol-induced hepatotoxicity.     

Effect of vitamin E on platelet enzymatic anti-oxidants in the patients of myocardial infarction

Effect of administration of 600 mg. vitamin E each day, for six days, was observed on activity of some of the anti-oxidant enzymes and levels of malondialdehyde (as an index of free radical mediated damage) in the platelets of patients reperfused after myocardial infarction. It has been found that vitamin E administration significantly lowers the level of malondialdehyde in the patients. Vitamin E administration increases the activities of anti oxidant enzymes (viz. superoxide dismutase, glutathione reductase and catalase) tested both in the patients and healthy controls. Vitamin E administration causes general stimulation of anti-oxidant enzyme activities both in healthy persons and the patients, however, lowering of lipid per-oxidation upon administration of vitamin E is specific for patients. These findings exhibit beneficial role of vitamin E administration in the management of the patients reperfused after myocardial infarction.     

Oxidative stress and antioxidants in tubercular meningitis

Oxidative stress is implicated in the etiopathogenesis of a variety of human diseases. Therefore, in the present study, erythrocyte lipid peroxidation, percentage hemolysis, antioxidant enzymes viz., glutathione reductase, glutathione peroxidase, superoxide dismutase and plasma antioxidants viz., ceruloplasmin, vitamins A,E and C have been determined in 19 patients with tubercular meningitis (TBM) and 50 normals. Six patients who were treated with antibiotics were considered for the follow up. The statistical analysis was carried out by Mann Whitney U test and Wilcoxon rank sum test. Lipid peroxidation (P<0.02), percentage hemolysis (P<0.001) and plasma ceruloplasmin (P<0.0001) of TBM patients were significantly higher, whereas erythrocyte glutathione reductase (P<0.05) and plasma antioxidant vitamins A, E and C (P<0.01, P<0.05 respectively) were significantly lower than those of the controls. In the follow up patients the glutathione reductase and catalase levels were significantly high (P<0.05) compared to their pre-treated condition. Vitamin C and E levels have attained normal range. This study indicated that the blood antioxidant status of TBM patients which was low compared to controls improved after treatment, suggesting the role of free radicals in TBM.     

Hypoglycemic, hypolipidemic and antioxidant properties of combination ofCurcumin fromCurcuma longa, Linn, and partially purified product fromAbroma augusta, Linn. in streptozotocin induced diabetes

Dietary spice components ofCurcuma longa andAbroma augusta have been screened for their protective effect against reactive oxygen species induced lipid peroxidation. They have been found to be efficient antioxidant when administered in combination. The purpose of the study was to investigate the effect of oral administration (300mg/Kg) of the aqueous extract of turmeric whose active ingredient isCurcumin andAbromine powder as a hypoglycemic agent mixed with diet. The effect of this aqueous extract on blood glucose, lipid peroxidation (LPO) and the antioxidant defense system in rat tissues like liver, lung, kidney and brain was studied for 8 weeks in streptozotocin induced diabetic rats. The administration of an aqueous extract of turmeric and abromine powder resulted in a significant reduction in blood glucose and an increase in total haemoglobin. The aqueous extract also resulted in decreased free radical formation in the tissues studied. The decrease in thiobarbituric acid reactive substances (TBARS) and increase in reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) clearly showed the antioxidant property of the mixture. It is suggested that these changes initially counteract the oxidative stress in diabetes however, a gradual decrease in the antioxidative process may be one of the factors which results in chronic diabetes. These results indicate that the mixture of the two plants have shown antidiabetic activity and also reduced oxidative stress in diabetes. A combination ofAbroma augusta and Curcuma longa also restored the other general parameters in diabetic animals. The results were statistically analyzed and indicated that combination of herbal extracts showed better efficacy as compared to individual herbal plant extracts used.     

Lipid peroxidation and antioxidant status in blood of rheumatoid arthritis patients

The main objective of the study was to assess the oxidative stress in plasma and erythrocytes of rheumatoid arthritis patients by measuring the levels of thiobarbituric acid reactive substances (TBARS), non-enzymatic antioxidants (vitamin E, C and reduced glutathione) and enzymatic antioxidants [superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSHPx)]. This study has been conducted on twenty-two adult female rheumatoid arthritis patients and an equal number of healthy subjects. Elevated lipid peroxidation and multidirectional changes in the antioxidant defence system were noticed in patients with rheumatoid arthritis. The enhanced lipid peroxidation accompanied by disturbance in antioxidant status indicates that rheumatoid arthritis patients are more prone to free radical mediated oxidative damage.     

Lipid peroxidation and antioxidant status in patients with rheumatoid arthritis

The changes in the erythrocyte lipid peroxidation products (MDA), levels of glutathione (GSH), ascorbic acid and plasma vitamin E (non enzymatic antioxidant parameters) and activities of antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase (GP_X), catalase in erythrocytes and plasma glutathione - S - transferase (GST) activity were estimated in patients with rheumatoid arthritis. This work was undertaken to assess oxidative stress and anti oxidant status in patients with rheumatoid arthritis. It was observed that there was a significant increase in erythrocyte MDA levels, activities of SOD, GP_X, plasma GST and a significant decrease in erythrocyte GSH, ascorbic acid, plasma vitamin E levels and catalse activity in patients with rheumatoid arthritis when compared to controls. The results of our study suggests higher oxygen free radical production, evidenced by increased MDA and decreased GSH, ascorbic acid, vitamin E and Catalase activity, support to the oxidative stress in rheumatoid arthritis. The increased activities of antioxidant enzymes may be a compensatory regulation in response to increased oxidative stress.     

The Appraisement of Antioxidant and Oxidant Status in Women Undergoing Surgical Menopause

The present study was undertaken to study the impact of surgical menopause on oxidant and antioxidant status in relation to estrogen levels after 3 months of surgery. Total 130 women who had undergone total hysterectomy (TH) with or without bilateral salpingo-oophorectomy (BSO) were included in this study. The oxidant status was assessed by measuring plasma levels of malondialdehyde and antioxidant status was assessed by measuring superoxide dismutase, catalase, glutathione, glutathione peroxidase, estrogen, and Vitamin A, E and C levels. The malondialdehyde level was significantly increased (p < 0.05) in all women who underwent TH with or without BSO. Significant increased levels of superoxide dismutase were observed in women who underwent TH with BSO. The blood glutathione levels were significantly decreased in women after TH only but significantly increased in women who had undergone TH with BSO. The levels of estrogen, vitamin E and vitamin C were significantly decreased in women who underwent TH with BSO. The catalase, GPx and vitamin A did not differ significantly in all groups. The result suggests that surgical menopause is associated with oxidative stress which reiterates the fact that ovaries retain some function even after menopause.     

Study of lipid peroxide and lipid profile in diabetes mellitus

The study was designed to find out the correlation between lipid peroxidation, lipoprotein levels to severity and complication of diabetes mellitus. Degree of lipid peroxidation was measured in terms of malondialdehyde (MDA) along with lipid profile and blood glucose in diabetes mellitus. It is categorised into insulin dependent diabetes mellitus (IDDM), non insulin dependent diabetes mellitus (NIDDM) and diabetes mellitus(DM) with complication. Total 112 known diabetic patients and 52 non-diabetic controls were studied. These patients were grouped as per the concentration of fasting blood glucose level i.e. controlled, poorly controlled, and uncontrolled group. There are significant increase in the lipid peroxide (MDA) and lipid profile except HDL cholesterol which is decreased, has been found in all groups as compared to controls In NIDDM group lipid peroxidation was markedly increased than IDDM group and it was higher in DM with complications. Other finding observed was that the level of lipid peroxide increased as per the increase in concentration of blood glucose. The increase lipid peroxidation in the hyperglycemic condition may be explained, as the superoxide dismutase enzyme which is antioxidant becomes inactive due the formation of superoxide radical within the cell. Maximum lipid peroxidation leads to the damage of the tissue and organs which results into complication in diabetic patients. High levels of total cholesterol appear due to increased cholesterol synthesis. The triglyceride levels changes according to the glycemic, control. The increase may be due to overproduction of VLDL-TG. It is concluded that good metabolic control of hyperglycemia will prevent in alteration in peroxidation and the lipid metabolism, which may help in good prognosis and preventing manifestation of vascular and secondary complication in diabetes mellitus.