Potential Association of Triglyceride Glucose Index with Cardiac Autonomic Neuropathy in Type 2 Diabetes Mellitus Patients.

Cardiac autonomic neuropathy (CAN) is a common and most neglected complication of diabetes, estimated to be roughly 8% in recently diagnosed patients and greater than 50% in patients with chronic disease history. The insulin resistance (IR) itself is bidirectionally associated with increased risk of type 2 diabetes mellitus (T2DM) and CAN is a predisposing factor. The primary objective of the present study was aimed to find a correlation of triglyceride glucose index (TyG index) in CAN patients along with the prevalence of CAN in T2DM patients as a secondary objective. This prevalence study was conducted on 202 patients visiting the diabetic clinic of Hamdard Institute of Medical Sciences and Research, Jamia Hamdard (HIMSR) teaching hospital in New Delhi, India who fulfilled the inclusion criteria. The Ewings autonomic function test was used for diagnosis of CAN. TyG index was calculated for patients based on fasting levels of glucose and triglyceride. The CAN was diagnosed in 62 participants out of 202 T2DM patients (overall prevalence 30.7%). The mean ± standard deviation (SD) for TyG index was 10.3 ± 0.2 and 9.5 ± 0.2 in CAN positive, T2DM patients, respectively. The difference of TyG index, in CAN positive and T2DM patients, was highly significant (P < 0.001). Further correlation analysis was performed to find an association of TyG index, duration, and age with patient groups. TyG index showed a positive correlation with heart rate during deep breathing (HRD), heart rate variation during standing (HRS), blood pressure (BP) response to handgrip and BP response to standing. Our finding highlights the TyG index, low-cost IR index, might be useful as an alternative tool for the early screening of patients at a high risk of diabetic neuropathy.

Protective effect of pioglitazone on cardiomyocyte apoptosis in low-dose streptozotocin & high-fat diet-induced type-2 diabetes in rats.

BACKGROUND & OBJECTIVES: Cardiomyocyte apoptosis is one of the pathologic phenomena associated with diabetes and related conditions including obesity, insulin resistance and hyperlipidaemia. In the present study, the protective effects of pioglitazone on cardiomyocyte apoptosis was evaluated in experimental diabetes induced by low dose of streptozoticin (STZ) combined with high fat diet (HFD) in rats. METHODS: Male Wistar rats (150-200 g) were injected with low-dose STZ (45 mg/kg, i.v., single dose) and orally fed with a HFD (20 g/day/rat) for a period of 28 days and simultaneously treated with pioglitazone (20 mg/kg/p.o.) for a period of 21 days (from 8 th day to 28 th day). On 29 th day blood was collected, serum separated and used for biochemical parameters. Heart tissue was used for cardiomyocyte apoptosis measurement and also for histopathological examination. RESULTS: Pioglitazone treatment resulted in a decrease in cardiomyocyte apoptosis as revealed by a decrease in cardiac caspase-3, lactate dehydrogenase (LDH) levels and DNA fragmentation, and an increase in Na+K+ATPase levels in diabetic rats. Cardiac histology of diabetic control rats showed dense focal fatty infiltration in the myocardial cells whereas normal architecture with regular morphology and well preserved cytoplasm was observed with pioglitazone treatment. Pioglitazone treatment significantly reduced the heart rate, mean arterial blood pressure, body mass index (BMI) and levels of serum glucose, leptin, insulin, HOMA-IR, total cholesterol (TC) and triglycerides (TGs), apoliproprotein-B glycosylated haemoglobin (HbA1c) levels and atherogenic index, and increased the levels of serum high density lipoprotein cholesterol (HDL-C) and cardiac antioxidant enzymes. INTERPRETATION & CONCLUSIONS: The present study results suggest that pioglitazone possesses cardiac anti-apoptotic potential in diabetic rat model and can be further explored for its use for treatment of diabetic cardiomyopathy.

Hidden attributes of zymosan in the pathogenesis of inflammatory diseases: A tale of the fungal agent.

Inflammation triggers immune system-mediated actions that contribute to the development of multiple diseases. Zymosan, a polysaccharide derived from the Saccharomyces cerevisiae cell wall, is mainly made up of glucan and mannan residues and is used as an inflammatory agent. Zymosan is a fungal product that activates the immune system through the activation of inflammatory signaling pathways, and releases a variety of harmful chemicals including pattern recognition receptors, reactive oxygen species (ROS), and the excitatory amino acid glutamate, cytokines, adhesion molecules, etc. Furthermore, we will dive into the molecular mechanistic insights through which this fungal agent induces and influences various inflammatory diseases such as cardiovascular, neuroinflammation, diabetes, arthritis, and sepsis. Based on the evidence, zymosan appears to be a promising inflammatory-inducing agent. Nonetheless, more animal data is the need of the hour to catch a glimpse and unravel the capacity of zymosan.

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.

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.

Effect of rosuvastatin on obesity-induced cardiac oxidative stress in Wistar rats--a preliminary study.

The prevalence of obesity has been rising alarmingly and it has now become a global concern causing an enormous economic burden on the health care system. Obesity is generally linked to complications in lipid metabolism and oxidative stress. The aim of the present study was to investigate the effect of rosuvastatin (10 mg/kg, po) on obesity-induced oxidative stress in high fat-fed Wistar rats. Oral administration of rosuvastatin (10 mg/kg) for 21 days along with high fat diet brought about significant elevation in serum high density lipoprotein and cardiac antioxidant enzymes levels (superoxide dismutase, catalase, glutathione, glutathione peroxidase, glutathione peroxidase-, glutathione reductase- and glutathione-S-transferase) while decreasing in serum lactate dehydrogenase, apolipoprotein-B, lipids (triglycerides, total cholesterol, low density lipoprotein-cholesterol, very low density lipoprotein-cholesterol and atherogenic index) and cardiac thiobarbituric acid reactive substances levels. The results were comparable with orlistat, a standard antiobesity drug. These preliminary results for the first time demonstrate that administration of rosuvastatin can be beneficial for the suppression of obesity-induced oxidative stress and dyslipidemia in high fat-fed Wistar rats.

Enhancement of antioxidant defense mechanism by pitavastatin and rosuvastatin on obesity-induced oxidative stress in Wistar rats.

CONTEXT: There has been a steady increase in the epidemiology of obesity over the last 30 years with developed countries leading the way. Oxidative stress was believed to be the principle contributor to the development of cardiovascular disorders that linked with obesity. OBJECTIVE: To evaluate the enhancement of antioxidant defense mechanism by Pitavastatin (PTV) and Rosuvastatin (RSV) on obesity-induced oxidative stress in Wistar rats. METHODS: Fifty Wistar albino rats were divided into five groups. High fat diet (HFD, 20 g/day/rat) pellets were given for 28 days to produce obesity-induced oxidative stress in Wistar rats. Oral administration of HFD along with PTV, RSV and Orlistat [(HFD for 28 days + from 8th day PTV (1 mg/kg), RSV (5 mg/kg) and Orlistat (10 mg/kg) to 28th day] were given respectively. RESULTS: Both PTV and RSV produced significant (p < 0.01) reduction in serum apolipoprotein-B (Apo-B), total cholesterol (TC), triglycerides (TGs), cardiac-lipid peroxides (TBARS) levels and elevation in serum high density lipoprotein (HDL-C), cardiac antioxidant enzymes [glutathione (GSH), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S-transferase (GST), superoxide dismutase (SOD) and catase (CAT)] levels. DISCUSSION AND CONCLUSION: Results were comparable with Orlistat, a standard antiobesity drug and present initial evidence that Pitavastatin and Rosuvastatin are useful for the treatment of obesity by enhancing the antioxidant defense mechanism. However, the effects of PTV were more prominent than RSV. The present findings of Pitavastatin and Rosuvastatin raise the possibility of a new application as an antiobesity therapeutic modality.

Anti-PCSK9 monoclonal antibody attenuates high-fat diet and zymosan-induced vascular inflammation in C57BL/6 mice by modulating TLR2/NF-ƙB signaling pathway.

Objectives: Excess intake of a high-fatty diet (HFD) together with zymosan administration mediates vasculitis response which leads to impaired serum lipid levels and causes arterial stiffness. In the development of new cholesterol-lowering medications, PCSK9 inhibitor (proprotein convertase subtilisin/kexin type 9) is an emerging therapeutic. The goal of the present study was to see whether anti-PCSK9 mAb1 might prevent vasculitis in C57BL/6 mice by blocking TLR2/NF-B activation in HFD and Zymosan-induced vasculitis. Materials and Methods: Protein-protein molecular docking was performed to validate the binding affinity of anti-PCSK9 mAb1 against TLR2. Under the experimental study, mice were randomly allocated to the following groups: Group I: standard mice diet (30 days) + Zymosan vehicle (sterile PBS solution of 5mg/ml on 8th day); Group II: HFD (30 days) + Zymosan ( single IP dose 80 mg/kg on day 8th); Group III: HFD+Zymosan + anti-PCSK9 mAb1 (6 mg/kg, s.c. on 10th and 20th days); Group IV: HFD+Zymosan+anti-PCSK9 mAb1 (10 mg/kg, s.c. on 10th and 20th days). Results: In comparison with the low dose of anti-PCSK9 mAb1 (6 mg/kg), the high dose of anti-PCSK9 mAb1 (10 mg/kg) together with HFD and Zymosan inhibited vasculitis more effectively by decreasing aortic TLR2 and NF-B levels, reducing serum TNF- and IL-6, and up-regulating liver LDLR levels, which down-regulated serum LDL-C and improved serum lipids levels. Histopathological studies showed that anti-PCSK9 mAb1 treatment reduced plaque accumulation in the aorta of mice. Conclusion: These findings indicate that anti-PCSK9 mAb1 has therapeutic potential in reducing HFD and Zymosan-induced vascular inflammation.

Saroglitazar ameliorates monosodium glutamate-induced obesity and associated inflammation in Wistar rats: Plausible role of NLRP3 inflammasome and NF- κB.

Objectives: Inflammation is the major progenitor of obesity and associated metabolic disorders. The current study investigated the modulatory role of saroglitazar on adipocyte dysfunction and associated inflammation in monosodium glutamate (MSG) obese Wistar rats. Materials and Methods: The molecular docking simulation studies of saroglitazar and fenofibrate were performed on the ligand-binding domain of NLRP3 and NF- κB. Under in vivo study, neonatal pups received normal saline or MSG (4 g/kg, SC) for 7 alternate days after birth. After keeping for 42 days as such, animals were divided into seven groups: Normal control; MSG control; MSG + saroglitazar (2 mg/kg); MSG + saroglitazar (4 mg/kg); saroglitazar (4 mg/kg) per se; MSG + fenofibrate (100 mg/kg); fenofibrate (100 mg/kg) per se. Drug treatments were given orally, from the 42nd to 70th day. On day 71, blood was collected and animals were sacrificed for isolation of liver and fat pads. Results: In silico study showed significant binding of saroglitazar and fenofibrate against NLRP3 and NF- κB. Saroglitazar significantly reduced body weight, body mass index, Lee's index, fat pad weights, adiposity index, decreased serum lipids, interleukin-1ß (IL-1ß), tumor necrosis factor-α(TNF-α), interleukin-6 (IL-6), leptin, insulin, blood glucose, HOMA-IR values, oxidative stress in the liver and increased hepatic low-density lipoprotein receptor levels. Histopathological analysis of the liver showed decreased inflammation and vacuolization, and reduced adipocyte cell size. Immunohistochemical analysis showed suppression of NLRP3 in epididymal adipocytes and NF- κB expression in the liver. Conclusion: Saroglitazar ameliorated obesity and associated inflammation via modulation of NLRP3 inflammasome and NF- κB in MSG obese Wistar rats.

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.

Modulatory role of atorvastatin against high-fat diet and zymosan-induced activation of TLR2/NF-ƙB signaling pathway in C57BL/6 mice.

OBJECTIVES: Accumulated evidence provides a strong connection between the immune system and vascular inflammation. The innate immune system's main sensors are toll-like receptors (TLRs). Zymosan (Zym), a fungal product, induces an inflammatory response via activating TLR2 of the immune system. Atorvastatin, a potent statin, possesses pleiotropic effects including immunomodulatory, lipid-lowering, and anti-inflammatory. Therefore, the current study aimed to evaluate the protective role of atorvastatin against a high-fat diet (HFD) and Zym-induced vascular inflammation in C57BL/6 mice via modulation of TLR2/NF-ƙB signaling pathway. MATERIALS AND METHODS: In silico study was conducted to confirm the binding affinity of atorvastatin against TLR2. Under in vivo study, mice were divided into four groups: Normal control: normal standard chow-diet fed for 30 days + Zym vehicle (sterile PBS, 5 mg/ml on 8th day); HFD (30 days) + Zym (80 mg/kg, IP, on 8th day); HFD/Zym + atorvastatin vehicle (0.5% CMC, p.o., from 10th to 30th day); HFD/Zym + atorvastatin (3.6 mg/kg, p.o., from 10th to 30th day). RESULTS: Atorvastatin treatment along with HFD and Zym inhibited vascular inflammation by suppressing the levels of aortic TLR2, cardiac NF-ƙB and decrease in serum TNF-α and IL-6. Further, there was an increase in hepatic LDLR levels, resulting in a decrease in serum LDL-C and an increase in HDL-C levels. Histopathological examination of the aorta showed a reduction in plaque accumulation with the atorvastatin-treated group as compared with HFD and Zym-treated group. CONCLUSION: Atorvastatin attenuates vascular inflammation mediated by HFD and Zym through suppression of TLR2, NF-ƙB, TNF-α, IL-6, and upregulation of LDLR levels.

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.

Involvement of the toll-like receptors-2/nuclear factor-kappa B signaling pathway in atherosclerosis induced by high-fat diet and zymosan A in C57BL/6 mice.

OBJECTIVE: Accumulated evidence reported a link between the immune system, microbial infection, and the development of atherosclerosis. Excess intake of high-fat diet (HFD) increases blood lipid levels and induces inflammatory pathways whereas zymosan A (Zym), a microbial component, mediates inflammatory response through the stimulation of specific ligand of toll-like receptors (TLRs) of the immune system. The current research work was aimed to evaluate the mechanism behind atherosclerosis mediated by HFD and Zym in C57BL/6 mice. MATERIALS AND METHODS: The mice were orally fed with HFD for 30 days and Zym (80 mg/kg, single intraperitoneal injection on day 8th). On the 31st day, blood was withdrawn from overnight fasted mice by tail vein puncture and estimated for serum lipids and tumor necrosis factor-alpha (TNF-α). Animals were sacrificed, and cardiac, liver, and aortic tissues were isolated for the estimation of cardiac TLR-2, nuclear factor-kappa B (NF-ƙB); hepatic low-density lipoprotein receptors (LDLR); and base of aorta analyzed for histopathology. RESULTS: It was found that HFD and Zym administration increased arterial inflammation directly through modulation of the TLR-2/NF-ƙB pathway, thereby upregulate serum TNF-α, cardiac TLR-2, and NF-ƙB levels. Further, HFD and Zym treatment significantly increased serum lipid levels and marked decrease in LDLR protein expression in the liver when compared to normal control mice. Histopathological analysis showed the formation of atherosclerotic plaque. CONCLUSION: The study is first, to our current knowledge, to demonstrate the involvement of the TLR-2/NF-ƙB signaling pathway in atherosclerosis induced by HFD and Zym in C57BL/6 mice, resulting in increased degradation of LDLR protein, thereby, increasing the serum lipid levels.

Suppression of isoproterenol-induced cardiotoxicity in rats by raspberry ketone via activation of peroxisome proliferator activated receptor-α.

The peroxisome proliferator-activated receptor-α (PPAR-α) controls the lipid and glucose metabolism and also affects inflammation, cell proliferation and apoptosis during cardiovascular disease. Raspberry ketone (RK) is a red raspberry (Rubusidaeus, Family-Rosaceae) plant constituent, which activates PPAR-α. This study was conducted to assess the cardioprotective action of RK against isoproterenol (ISO)-induced cardiotoxicity. Wistar rats were randomly divided into six groups (six rats/group). Rats were orally administered with RK (50, 100 and 200 mg/kg, respectively) and fenofibrate (standard, 80 mg/kg) for 28 days and ISO was administered (85 mg/kg, subcutaneously) on 27th and 28th day. Administration of ISO in rats significantly altered hemodynamic and electrocardiogram patterns, total antioxidant capacity, PPAR-α, and apolipoprotein C-III levels. These myocardial aberrations were further confirmed during infarct size, heart weight to body weight ratio and immunohistochemical assessments (caspase-3 and nuclear factor-κB). RK pretreatment (100 and 200 mg/kg) significantly protected rats against oxidative stress, inflammation, and dyslipidemia caused by ISO as demonstrated by change in hemodynamic, biochemical and histological parameters. The results so obtained were quite comparable with fenofibrate. Moreover, RK was found to have binding affinity with PPAR-α, as confirmed by docking analysis. PPAR-α expression and concentration was also found increased in presence of RK which gave impression that RK probably showed cardioprotection via PPAR-α activation, however direct binding study of RK with PPAR-α is needed to confirm this assumption.

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.

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.

Raspberry ketone protects against isoproterenol-induced myocardial infarction in rats.

AIM: The cardioprotective role of raspberry ketone (RK) against isoproterenol (ISO)-induced myocardial infarction (MI) in rats was assessed. MATERIALS AND METHODS: Rats were randomly divided into Group I - Vehicle control; Group II - Toxic control ISO (85mg/kg, s.c.); Group III, IV and V - RK (50, 100 and 200mg/kg, respectively) with ISO; Group VI- RK (200mg/kg) alone; Group VII - Propranolol (10mg/kg) with ISO; and Group VIII - Propranolol (10mg/kg) alone. After twenty-four hours of the last dose, animals were sacrificed and creatine kinase-MB, lactate dehydrogenase, total cholesterol, triglycerides, high-density-lipoprotein, low-density-lipoprotein, very-low-density-lipoprotein, malondialdehyde, reduced glutathione, superoxide dismutase, catalase, Na+, K+-ATPase, nitric oxide, histopathological and immunohistochemical analysis (tumor necrosis factor-α and inducible nitric oxide synthase) were performed. KEY FINDINGS: Treatment with ISO significantly deviated the biochemical parameters from the normal levels, which were considerably restored by RK at 100 and 200mg/kg doses. 50mg/kg dose, however, did not demonstrate any significant cardioprotective action. The histopathological and immunohistochemical analysis further substantiated these findings. SIGNIFICANCE: Our study showed a dose-dependent reduction in oxidative stress, inflammation and dyslipidemia by RK in ISO-intoxicated rats, which signifies that RK from the European red raspberry plant might be a valuable entity for the management of MI.