Trigonelline inhibits intestinal microbial metabolism of choline and its associated cardiovascular risk.

Gut microbiota based metabolism of choline produces trimethylamine (TMA) which is further converted to a pro-atherosclerotic metabolite, trimethylamine-N-oxide (TMAO) by flavin monooxygenase (FMO3). Trigonelline from the plant Trigonella foenum-graecum has been reported for the treatment of CVD. Aim of the present study was to check the effect of trigonelline on the gut microbiota based conversion of TMA to TMAO. Trigonelline was isolated from hydroalcoholic extract of seeds of Trigonella foenum-graecum. The isolated trigonelline was characterized through TLC and UPLC-MS. Anaerobic microbe responsible for the metabolism of choline to TMA was isolated by culturing the human gut microbiota in choline enriched medium. The isolated bacteria was identified at molecular level based on PCR amplification of 1500bp of 16S rRNA gene sequence. Isolated FMO3 was used for ex vivo conversion of TMA to TMAO. Further, we investigated the effect of trigonelline in isolated gut microbe based metabolism of choline, lipid profile and TMAO levels in mice with or without suppression of gut microbiota with antibiotics. Liquid-liquid purification and chromatographic analysis confirmed the trigonelline purity (87.26%) and which was also confirmed by mass spectroscopy with m/z 137.4 in positive ionization mode. A total of 30 anaerobic microbes responsible for TMA production were isolated and Citrobacter freundii was the superior among others for the production of TMA. In vitro culture of C. freundii in choline enriched medium supplemented with trigonelline resulted in significantly reduction TMA and followed by TMAO production. In ex vivo, a maximum of 85.3% TMAO production was reduced by trigonelline at concentration of about 300 µg/mL. Serum level of lipids and TMAO were significantly altered in choline fed animals with or without suppression of gut microbiota and this phenomenon was reversed upon the oral administration of trigonelline in a dose-dependent manner. This study demonstrates the effect of trigonelline on gut microbiota responsible for choline metabolism and this can be used as a model for evaluation of herbal drugs and its effect in gut microbiota prompted cardiovascular disorders.

Fenugreek seed extract inhibit fat accumulation and ameliorates dyslipidemia in high fat diet-induced obese rats.

This study investigated the inhibitory effect of aqueous extract of Trigonella foenum-graecum seeds (AqE-TFG) on fat accumulation and dyslipidemia in high fat diet- (HFD-) induced obese rats. Female Wistar rats were fed with HFD ad libitum, and the rats on HFD were treated orally with AqE-TFG or orlistat ((HFD for 28 days+AqE-TFG (0.5 and 1.0 g/kg) or orlistat (10 mg/kg) from day 8 to 28), respectively. Treatment with AqE-TFG produced significant reduction in body weight gain, body mass index (BMI), white adipose tissue (WAT) weights, blood glucose, serum insulin, lipids, leptin, lipase, and apolipoprotein-B levels and elevation in adiponectin levels. AqE-TFG improved serum aspartate amino transferase (AST), alanine amino transferase (ALT), and lactate dehydrogenase (LDH) levels. AqE-TFG treatment reduced the hepatic and cardiac thiobarbituric acid reactive substances (TBARS) and elevated the antioxidant enzyme (glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT)) levels. In addition, liver and uterine WAT lipogenic enzyme (fatty acid synthetase (FAS) and glucose-6-phosphate dehydrogenase (G6PD)) activities were restored towards normal levels. These findings demonstrated the preventive effect of AqE-TFG on fat accumulation and dyslipidemia, due to inhibition of impaired lipid digestion and absorption, in addition to improvement in glucose and lipid metabolism, enhancement of insulin sensitivity, increased antioxidant defense, and downregulation of lipogenic enzymes.

Protective effect of Trigonella foenum-graecum Linn. on monosodium glutamate-induced dyslipidemia and oxidative stress in rats.

OBJECTIVES: The present study was designed to evaluate the effect of aqueous extract of Trigonella foenum-graecum(AqE-TFG) seeds on monosodium glutamate (MSG)-induced dyslipidemia and oxidative stress in Wistar rats. MATERIALS AND METHODS: Neonatal Wistar rats were treated subcutaneously with MSG (4 g/kg b.w.) from day 2 to 14 after birth, on alternate days. After attaining six-weeks of age, MSG-treated rats were administered with AqE-TFG (0.5 and 1 g/kg b.w., orally) or orlistat (10 mg/kg b.w., orally) for 28 days, respectively. Serum chemistry and relevant enzymes in hepato-cardiac tissues were assessed on day 29. RESULTS: AqE-TFG produced significant reduction in serum total cholesterol (TC), triglycerides (TGs), lactate dehydrogenase (LDH), aspartate amino transferase (AST), alanine amino transferase (ALT), hepatic and cardiac lipid peroxides (MDA) levels and elevation in serum high density lipoprotein cholesterol (HDL-C), hepatic and cardiac antioxidant enzymes [glutathione (GSH), and superoxide dismutase (SOD) and catalase (CAT)] levels. CONCLUSION: Results were comparable with orlistat, a standard anti-obesity drug, and provide clear evidence that the AqE-TFG treatment offered significant protection against MSG-induced dyslipidemia and oxidative stress, and may play an important role in amelioration of the free radical generated consequences like dyslipidemia and atherosclerosis.

Evaluation of antiobesity and cardioprotective effect of Gymnema sylvestre extract in murine model.

OBJECTIVE: Obesity plays a central role in the insulin resistance syndrome, which is associated with hyperinsulinemia, hypertension, hyperlipidemia, type 2 diabetes mellitus, and an increased risk of atherosclerotic cardiovascular disease. The present study was done to assess the effect of Gymnema sylvestre extract (GSE) in the high fat diet (HFD)-induced cellular obesity and cardiac damage in Wistar rats. MATERIALS AND METHODS: Adult male Wistar rats (150-200 g body weight) were used in this study. HFD was used to induce obesity. Body mass index, hemodynamic parameters, serum leptin, insulin, glucose, lipids, apolipoprotein levels, myocardial apoptosis, and antioxidant enzymes were assessed. Organ and visceral fat pad weights and histopathological studies were also carried out. RESULTS: Oral feeding of HFD (20 g/day) for a period of 28 days resulted in a significant increase in body mass index, organ weights, visceral fat pad weight, cardiac caspase-3, cardiac DNA laddering (indicating apoptotic inter-nucleosomal DNA fragment), and lipid peroxide levels of cardiac tissues of rats. Further, mean arterial blood pressure, heart rate, serum leptin, insulin, LDH, LDL-C, total cholesterol, triglycerides, and apolipoprotein-B levels were enhanced significantly, whereas serum HDL-C, apoliporotein-A1 levels, and cardiac Na(+) K(+) ATPase, antioxidant enzymes levels were significantly decreased. Furthermore, treatment with standardized ethanolic GSE (200 m/kg/p.o.) for a period of 28 days resulted in significant reversal of above mentioned changes in the obese Wistar rats. CONCLUSION: The present study has demonstrated the significant antiobesity potential of GSE in murine model of obesity.

Anti-apoptotic potential of gymnemic acid phospholipid complex pretreatment in Wistar rats with experimental cardiomyopathy.

Cardiomyocyte apoptosis in heart failure has been the topic of research in many recent studies. In the present investigation, the potential cardioprotective effect of gymnemic acid phospholipid complex (GPC) on myocardial apoptosis and cardiac function was studied in doxorubicin (DOX; 30 mg/kg/ip/single dose)-induced cardiomyopathy model in rats. Doxorubicin induced cardiomyopathy was evidenced by significant hemodynamic changes (increased systolic, diastolic, mean arterial pressure and heart rate), decreased heart weight to body weight ratio, increase in serum lactate dehydrogenase (LDH) and Ca2+ levels and decrease in myocardial Na+/K+ ATPase levels along with caspase-3 activation. A marked reduction in glutathione, glutathione peroxidase, glutathione reductase, glutathione-S-transferase, superoxide dismutase and catalase levels along with increase in the levels of thiobarbituric acids (TBARS) were also observed in rat myocardium. In addition, DNA laddering observed on agarose gel electrophoresis and cardiac histopathology study further supplemented myocardial apoptosis. Pre-treatment with GPC significantly reduced DOX-induced cardiac toxicity, including improvement of hemodynamic variables and heart weight to body weight ratio, decreased serum Ca2+ level and LDH levels, myocardial caspase-3 levels, increased Na+/K+ ATPase levels and decreased myocardial TBARS levels and elevated antioxidant enzymes as compared to pathogenic control group. Further, the anti-apoptotic effect of GPC was verified by prevention of internucleosomal DNA laddering on agarose gel electrophoresis and attenuation of histopathological perturbations by doxorubicin. These observations demonstrate that GPC might serve as a cardioprotective formulation in DOX-induced cardiomyopathy in rats.

Preventive effect of embelin from embelia ribes on lipid metabolism and oxidative stress in high-fat diet-induced obesity in rats.

A high-fat diet (HFD) results in hyperlipidemia and an increase in oxidative stress. The purpose of this study was to investigate the preventive effect of embelin against hyperlipidemia and oxidative stress in HFD-induced obesity in rats. Male Wistar rats aged 12 weeks (150-200 g) were fed with an HFD for a period of 28 days to induce experimental obesity. HFD-induced obese rats were treated with embelin (50 mg/kg) or orlistat (10 mg/kg) for 21 days. A range of parameters were tested including body weight gain, body mass index (BMI), blood pressure, visceral fat pad weights, serum levels of glucose, insulin, leptin, apolipoprotein B (ApoB), total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), hepatic thiobarbituric acid-reactive substances (TBARS), superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH). Twenty-one days of embelin (50 mg/kg) treatment produced effects similar to orlistat in reducing body weight gain, blood pressure, visceral fat pad weight, serum lipid levels, as well as coronary artery risk and atherogenic indices of HFD-fed rats. Embelin treatment also lowered the serum levels of glucose by 24.77 %, insulin by 35.03 %, and leptin by 43.39 %. Furthermore, embelin treatment significantly (p < 0.01) decreased the hepatic TBARS levels, while increasing the SOD, CAT, and GSH levels in obese rats. The present study indicated the preventive effect of embelin in HFD-induced obesity and its related complications. Embelin could be valuable in the development of new drug therapies to prevent obesity, hyperlipidemia, and oxidative stress.

Ameliorative role of atorvastatin on methionine-induced hyperhomocysteinemia and hematological changes in albino rats.

Methionine (1g/kg, po) administration to pathogenic control rats for 30 days significantly increased the levels of homocysteine, total cholesterol (TC), low density lipoprotein (LDL-C), very low density lipoprotein (VLDL-C) and triglycerides (TGs) and decreased the levels of high density lipoprotein (HDL-C) in serum. Hematological observations of the peripheral blood smears of pathogenic rats fed with methionine also showed crenation of RBCs cell membrane and significant increase in total leukocyte count, differential leukocyte count and platelet counts with significant decrease in the mean hemoglobin levels as compared to vehicle control rats. Administration of atorvastatin (0.2 mg/kg/po) to hyperhomocysteinemic rats significantly decreased the levels of homocysteine, TC, TGs, LDL-C and VLDL-C and increased the levels of HDL-C in serum. The present results provide clear evidence that oral treatment with atorvastatin exhibit homocysteine and lipid lowering activity and also reversal of hematological changes induced by methionine in albino rats.

Antiapoptotic potential of herbal drugs in cardiovascular disorders: an overview.

Cardiomyocyte apoptosis has been reported in a number of cardiovascular disorders, including myocardial infarction, ischemia-reperfusion, end-stage heart failure, arrhythmogenic right ventricular dysplasia, and adriamycin-induced cardiomyopathy. Prevention of myocyte apoptosis has emerged as a potential new target in a multimodel therapeutic approach to cardiac disease. Herbal therapy may be an alternative strategy for the prevention and treatment of heart disease. The present review summarizes the list of plants/herbal formulations studied for their antiapoptotic activity in cardiovascular disorders. However, despite extensive positive research data from experimental studies for herbal drugs in cardiovascular disorders, and the anecdotal clinical experience of many practitioners and patients, its potential in the field of cardiac apoptosis remains largely untapped, and large scale clinical trials are needed to explore the potential of herbal medicines as a new treatment regime for targeting cardiovascular apoptosis.

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.

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.

Evaluation of antioxidant and neuroprotective effect of ethanolic extract of Embelia ribes Burm in focal cerebral ischemia/reperfusion-induced oxidative stress in rats.

Antioxidants have been the focus of studies for developing neuroprotective agents to be used in the therapy for stroke, which is an acute and progressive neurodegenerative disorder and is the second leading cause of death throughout the world. In fact, many herbal antioxidants have been developed in in vitro and in vivo experiments and some of these have been tested in clinical studies of stroke. Embelia ribes have been reported to have antioxidant and antidiabetic effects. In addition to these effects, this study was designed to investigate the neuroprotective effect of ethanolic extract of E. ribes Burm fruits on middle cerebral artery occlusion (MCAO)-induced focal cerebral ischemia in rats. Male Wistar albino rats were fed ethanolic E. ribes extract (100 and 200 mg/kg body weight; p.o.) for 30 days. After 30 days of feeding, all 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. Ischemia followed by reperfusion in ischemic group rats significantly (P < 0.001) reduced the grip strength activity and non-enzymatic (reduced glutathione, GSH) and enzymatic [glutathione peroxidase (GPx), glutathione reductase (GR) and glutathione-S-transferase (GST)] antioxidant levels in hippocampus and frontal cortex compared to sham-operated rats. Further, serum lactate dehydrogenase (LDH) and thiobarbituric acid reactive substance (TBARS) levels in hippocampus and frontal cortex were significantly increased in ischemic group compared to sham-operated rats. Furthermore, ethanolic E. ribes extracts pretreatment significantly (P < 0.001) increased the grip strength activity, and GSH, GPx, GR and GST levels in hippocampus and frontal cortex with significant decrease in LDH levels in serum and TBARS levels in hippocampus and frontal cortex compared to MCAO + vehicle group rats. The data from this study suggest that chronic treatment with ethanolic E. ribes extract enhances the antioxidant defense against MCAO- induced focal cerebral ischemia in rats and exhibits neuroprotective activity.

Further studies on antioxidant potential and protection of pancreatic beta-cells by Embelia ribes in experimental diabetes.

This study was designed to examine the antioxidant defense by ethanolic extract of Embelia ribes on streptozotocin-(40 mg/kg, intravenously, single-injection) induced diabetes in Wistar rats. Forty days of oral feeding the extract (100 mg/kg and 200 mg/kg) to diabetic rats resulted in significant (P < .01) decrease in blood glucose, blood glycosylated haemoglobin, serum lactate dehydrogenase, creatine kinase, and increase in blood glutathione levels as compared to pathogenic diabetic rats. Further, the extract also significantly (P < .01) decreased the pancreatic thiobarbituric acid-reactive substances (TBARS) levels and significantly (P < .01) increased the superoxide dismutase, catalase, and glutathione levels as compared to above levels in pancreatic tissue of pathogenic diabetic rats. The islets were shrunken in diabetic rats in comparison to normal rats. In the drug-treated diabetic rats, there was expansion of islets. The results of test drug were comparable to gliclazide (25 mg/kg, daily), a standard antihyperglycemic agent. The study concludes that Embelia ribes enhances the antioxidant defense against reactive oxygen species produced under hyperglycemic condition and this protects beta-cells against loss, and exhibit antidiabetic property.

Effect of ethanolic extract of Zingiber officinale on dyslipidaemia in diabetic rats.

The lipid lowering and antioxidant potential of ethanolic extract of Zingiber officinale Roscoe (family, Zingiberaceae) was evaluated in streptozotocin (STZ)-induced diabetes in rats. Ethanolic extract of Zingiber officinale (200 mg/kg) fed orally for 20 days produced, significant antihyperglycaemic effect (P < 0.01) in diabetic rats. Further, the extract treatment also lowered serum total cholesterol, triglycerides and increased the HDL-cholesterol levels when compared with pathogenic diabetic rats (P < 0.01). STZ-treatment also induced a statistically significant increase in liver and pancreas lipid peroxide levels (P < 0.01) as compared to normal healthy control rats. Zingiber officinale extract treatment lowered the liver and pancreas thiobarbituric acid reactive substances (TBARS) values (P < 0.01) as compared to pathogenic diabetic rats. The results of test drug were comparable to gliclazide (25 mg/kg, orally), a standard antihyperglycaemic agent. The results indicate that ethanolic extract of Zingiber officinale Roscoe can protect the tissues from lipid peroxidation. The extract also exhibit significant lipid lowering activity in diabetic rats. The present study is the first pilot study to assess the potential of Zingiber officinale in diabetic dyslipidaemia.

Effect of ethanolic extract of Embelia ribes on dyslipidemia in diabetic rats.

Diabetes mellitus has been treated orally with herbal remedies based on folk medicine since ancient times. Embelia ribes burm (Myrsinaceae), known commonly as vidanga, was used in Ayurveda for its anthelmintic activity. Ayurveda describes vidanga as pungent, causes increase in digestive fire, and cures flatulence and colic. A single study reported the antihyperglycemic activity of decoction of E. ribes in glucose-induced hyperglycemic albino rabbits. In the present study, the lipid-lowering and antioxidant potential of ethanolic extract of E. ribes burm was investigated in streptozotocin (40 mg/kg, IV, single injection)-induced diabetes in rats. Twenty days of orally feeding the extract (200 mg/kg) to diabetic rats resulted in significant (P < 0.01) decrease in blood glucose, serum total cholesterol, and triglycerides, and increase in HDL-cholesterol levels when compared to pathogenic diabetic rats. Further, the extract also lowered the liver and pancreas thiobarbituric acid-reactive substances (TBARSs) values (P < 0.01) when compared to TBARS values of liver and pancreas of pathogenic diabetic rats. The results of test drug were comparable to gliclazide (25 mg/kg, orally), a standard antihyperglycemic agent. This is the first pilot study to provide biochemical evidence of potential of E. ribes in diabetic dyslipidemia.