Vanillin rich fraction regulates LDLR and HMGCR gene expression in HepG2 cells

Vanillin and its analogs have been exploited for their various health benefits. This work aimed to investigate the antioxidant properties and regulatory effects of vanillin rich fraction (VRF) extracted from vanilla pods using the supercritical fluid extraction (SFE) and commercial vanillin on low density lipoprotein receptor (LDLR) and 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) gene expression in HepG2 cells. The vanillin content in the VRF was 2.6% (w/w) obtained at a temperature of 80 °C and a pressure of 600 bar. The VRF exhibited better antioxidant activity compared to the vanillin in DPPH and BCB tests. LDLR mRNA level was increased significantly by 2, 3 and 1.3 fold in the VRF treated cells at 100, 200 and vanillin treated cells at 100, respectively, compared with untreated cells. On the other hand, the HMGCR mRNA level was decreased significantly by 14, 58 and 13% respectively, in the VRF treated cells at 100, 200 and V treated cells at 100, respectively, compared with untreated cells. The VRF showed potential antioxidant activity and regulated genes involved in cholesterol metabolism including LDLR and HMGCR in dose-dependent manner.     

Alleviation of plasma,erythrocyte and liver lipidemic-oxidative stress by thymoquinone and limonene in atherogenic suspension fed rats

In the present study, the antioxidant efficacies of thymoquinone (TQ) and limonene (LMN), two main constituents of Nigella sativa seeds, were investigated in relation to plasma, erythrocyte and liver oxidative abnormalities in hyperlipidemic Wistar albino rats. Pretreatment with 10 mg TQ or 200 mg LMN in atherogenic suspension fed rats, effectively reduced the plasma lipid peroxidation markers, conjugated diene, lipid hydroperoxide, malondialdehyde, and replenished the plasma antioxidant capacity by increasing its ferric reducing ability and 2,2-azinobis-3-ethylbenzothiazoline-6-sulfonic acid quenching to near normal levels and modulating the levels of reduced glutathione, enzymatic antioxidants superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione-S-transferase, and erythrocyte membrane-linked ATPases to normalcy. These results demonstrate that radical scavenging/antiperoxidative efficacies of TQ were greater than LMN. Thus, these compounds, especially TQ, play an important and useful role in the preservation of plasma antioxidant status, cellular membrane structure and function of tissues, and may be used as chemopreventative food additives in the prooxidant state related disorders.     

Suppression of diet-induced hypercholesterolaemia by saponins from Panax notoginseng in rats

Panax notoginseng saponins (PNS) are major active constituents of P. notoginseng. This study investigated the mechanisms of the hypocholesterolaemic and atheroscleroprotective effects of PNS. It was found that treatment of PNS (30 or 100 mg/kg/day, p.o.) could significantly reduce elevated serum total cholesterol, triacylglycerol, low-density lipoprotein cholesterol and atherogenic index induced by feeding rats with high cholesterol diet for 28 days. High-density lipoprotein cholesterol could also be increased by PNS treatment. Additionally, PNS significantly enhanced the hypercholesterolaemia-induced reduction of superoxide dismutase activity in the liver. In hypercholesterolaemic rats, PNS significantly improved the endothelium-dependent vasodilatation, acetylcholine-induced nitric oxide production and endothelial nitric oxide synthase mRNA expression in a dose-dependent manner. It also significantly reversed the hypercholesterolaemia-induced changes in mRNA expressions of cholesterol 7α-hydroxylase and peroxisome proliferator-activated receptor α but not HMG-CoA reductase. The findings provided evidence for using PNS to prevent the development of hypercholesterolaemia and atherosclerosis. The hypocholesterolaemic activity of PNS is likely to be resulted from inducing the biosynthesis of bile acids from cholesterol and promoting the β-oxidation of fatty acids in the liver. The vasoprotective function of PNS may be brought about by increasing the gene expression of eNOS in endothelial cells, its antioxidative activity, or both.     

Preventive effects of caffeic acid on lipids,lipoproteins and glycoproteins in isoproterenol induced myocardial infarcted rats

Dietary phenolic compound intake has been reported inversely related to the incidence of cardiovascular diseases. The aim of this research was to understand the preventive effects of caffeic acid, a phenolic acid on lipids, lipoproteins and glycoprotein components in isoproterenol induced myocardial infarcted rats. Rats were pretreated with caffeic acid (15 mg/kg body weight) daily for a period of 10 days. After pretreatment, rats were induced myocardial infarction by subcutaneous injection of isoproterenol (100 mg/kg body weight). Isoproterenol induced myocardial infarcted rats showed significant (P < 0.05) decreased levels of heart phospholipids and significant (P < 0.05) increased levels of serum and heart cholesterol, triglycerides, free fatty acids and serum phospholipids. Isoproterenol also significantly (P < 0.05) increased low density and very low density lipoprotein cholesterol and significantly (P < 0.05) decreased high density lipoprotein cholesterol levels. The activity of liver 3-hydroxy-3methyl glutaryl-coenzyme-A-reductase was significantly (P < 0.05) increased and lecithin cholesterol acyl transferase activity was significantly (P < 0.05) decreased in isoproterenol induced myocardial infarcted rats. In addition, the levels of glycoprotein components in the serum and heart were significantly (P < 0.05) increased in myocardial infarcted rats. Pretreatment with caffeic acid positively altered all the above mentioned biochemical parameters studied in isoproterenol induced myocardial infarcted rats.In conclusion, caffeic acid protected the rat's heart from the deleterious effects of lipids, lipoproteins and glycoproteins by its antilipidemic and antiglycative effects in isoproterenol induced myocardial infarcted rats. A diet containing caffeic acid may be beneficial to myocardial infarction.     

Antihyperlipidemic effect of diosmin: A citrus flavonoid on lipid metabolism in experimental diabetic rats

The present study was hypothesized to evaluated the antihyperlipidemic effect of diosmin (DS) on lipid metabolism in experimental diabetic rats. Diabetes was induced male albino Wistar rats by intraperitoneal administration of streptozotocin (STZ) (45 mg/kg b.w.) 15 min after the ip administration of nicotinamide (NA) (110 mg/kg b.w.). DS were administered to diabetic rats intragastrically at 100 mg/kg b.w. for 45 days. The levels of plasma and tissue lipids (cholesterol, triglycerides) (TGs), free fatty acids (FFAs) and phospholipids (PLs), low density, very low-density lipoproteins (LDL and VLDL), and high-density-cholesterol (HDL-C) were measured. The activities of 3-hydroxy 3-methylglutaryl coenzyme A (HMG-CoA) reductase, lipoprotein lipase (LPL) and lecithin cholesterol acyl transferase (LCAT) were assayed. The levels of plasma and tissue lipids decreased with significant increase in HDL-C levels. The altered activities of lipid metabolic enzymes were restored to near normal. The present findings suggest that DS can potentially ameliorate lipid abnormalities in experimental diabetes.     

Phytochemical,Toxicological, Biochemical and Haematological Studies on Avocado (Persea americana) in Experimental Animals

The avocado tree belongs to the family lauraceae and is classified as Persea americana. The analysis of the fruits extract revealed the presence of considerable amounts of vitamins A, B₂, C, K, folic acid, lutein, zeaxanthin, coenzyme Q₁₀ and beta-carotene. When administered to wistar rats for acute toxicity studies, the animals did not exhibit any sign of toxicity even when large doses were given. The maximum tolerable dose (MTD) was therefore determined to be ≥ 10 g/kg body weight. The extract was found to significantly decrease (p < 0.05) the activity of liver and heart enzymes in the treated animals when compared with the control. The extract decreased total cholesterol (TC) by 37.97%, triglycerides by 37.87%, very low density lipoproteins(VLDL) by 47,41%, low density lipoproteins(LDL) by 59.57%, and at the same time increased high density lipoprotein (HDL) by 3.64%. The extract also decreased the prothrombin time (PT) and the partial prothrombo plastin time with kaolin (PTTK). These results are discussed with regard to the preventive and possible curative values of this extract as a potential inhibitor of cardiovascular diseases and in the regulation of blood clotting time due to its significant vitamin K content.     

Cholesterol lowering and vascular protective effects of ethanolic extract of dried fruit of Crataegus pinnatifida,hawthorn (Shan Zha), in diet-induced hypercholesterolaemic rat model

Consumption of functional foods for managing plasma cholesterol level has gained acceptance globally. The hypocholesterolaemic and vascular protective effects of the dried fruit of Crataegus pinnatifida, hawthorn (Shan Zha), were investigated in rats fed with normal diet, high cholesterol diet (HCD) or HCD plus Shan Zha 80% ethanolic extract treatment (30 or 100 mg/kg/day, p.o.) for 4 weeks. Shan Zha extract markedly reversed the increased plasma total cholesterol and high density lipoprotein cholesterol induced by HCD with a dose-dependent improvement on the atherogenic index. It also demonstrated good hepatoprotective function by reducing lipid content in the liver. The blunted endothelium-mediated aortic relaxation in HCD-fed rats was restored by high dosage of Shan Zha extract treatment. The current results showed that Shan Zha extract could provide its cholesterol lowering effect by up-regulating hepatic CYP7A1 mRNA expression which leads to enhanced bile acid biosynthesis. It is postulated that the hypocholesterolaemic effect is the primary beneficial effect given by Shan Zha extract; it then leads to other secondary beneficial effects such as vascular protective and hepatoprotective functions. Thus, Shan Zha extract could provide an overall improvement on the hepatic and vascular systems that may be important in relieving hypercholesterolaemia-related complications.     

Effects of a black rice extract (Oryza sativa L. indica) on cholesterol levels and plasma lipid parameters in Wistar Kyoto rats

This study was designed to evaluate the efficacy of an anthocyanin pigmented rice (e.g. black rice) to mitigate the onset of hypercholesterolemia in rats-fed atherogenic diets. Male Wistar (n = 10/group) rats were fed with atherogenic diets containing 0.5% cholesterol in the presence and in the absence of bile salt (e.g. 0.05% cholic acid) along with a standardized black rice extract (BRE) (e.g. 3%, w/w). All animals were individually housed in stainless steel cages and fed with the experimental diets during a 12-h period for 10 weeks. Body weights of rats were measured every week of the experiment. After 10 weeks fed on experimental diets, rats were sacrificed and plasma total cholesterol, HDL and LDL cholesterol and triacylglycerols were measured immediately. The total cholesterol (TC) content in the liver, heart and aorta, and the concentration of triacylglycerol (TAG) were measured after lipid extraction using Folch method. Rats fed with 0.5% cholesterol containing diets which also included bile salt exhibited a considerably more severe hypercholesterolemia than counterparts fed diets containing only 0.5% cholesterol. The inclusion of the BRE in diets significantly (p < 0.05) decreased the level of TC, LDL–TC and TAG in plasma of rats-fed control diets that either contained or were absent in bile salt (p < 0.05). There were no differences in HDL-level. Liver crude lipids and total cholesterol levels were also significantly (p < 0.05) decreased in experimental groups relative to the control group in both experiments. Thus, supplementation of atherogenic experimental diets with BRE effectively decreased lipid levels in hypercholesterolemic rats. In lieu of the mixture of bioactive components present in BRE, it is possible that more than one mechanism underlying this reduction in lipids is involved.     

β-Conglycinin (7S) and glycinin (11S) exert a hypocholesterolemic effect comparable to that of fenofibrate in rats fed a high-cholesterol diet

The hypocholesterolemic effect of isolated soybean proteins and fenofibrate in rats was compared. Forty-five rats were divided into five groups: standard (STD; casein), high cholesterol (HC; STD plus 1% cholesterol/0.5% cholic acid), HC + β-conglycinin, HC + glycinin and HC + fenofibrate. The proteins and the drug were administered by gavage for 28 days. The proteins decreased total cholesterol (TC) and triacylglycerol (TG) in the plasma of the rats fed HC diet, to values very close to those fed on fenofibrate. High density lipoprotein cholesterol (HDL-C) levels in the plasma were increased by the β-conglycinin, glycinin and fenofibrate groups. The largest TC reduction in the liver was observed in the fenofibrate group; in contrast, the β-conglycinin and glycinin groups exhibited reduced the levels of hepatic TG and TC. Based on these data, it could be suggested that the oral daily administration of isolated soybean proteins, in the range of 2.75% of the protein ingested daily, can promote a reduction in TC and TG in the plasma of rats fed hypercholesterolemic diets.     

Hypocholesterolemic effect of dietary evening primrose (Oenothera paradoxa) cake extract in rats

The objective of this study was to determine the effects of dietary evening primrose cake extract (E) on the lipid indices and lipid peroxidation products in growing rats fed cholesterol-free standard diet (S) or diets enriched with 1% cholesterol (C). All animals were divided into five groups of 10 and were fed during 4 weeks experimental diets: group (Gr) 1–standard diet (S); Gr 2–S diet supplemented with 1% E (S+1%E); Gr 3–with 1% C (S+1%C); Gr 4–S+1%C+0.5%E and Gr 5–S+1%C+1%E. Dietary E significantly decreased plasma total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C) but did not change the high density lipoprotein cholesterol (HDL-C) either in rats fed cholesterol-free or enriched-in-cholesterol diets. Plasma TC were 98.7, 81.3, 144.6, 114.5 and 99.1 mg 100 ml⁻¹, whereas LDL-C values were 19.4, 7.6, 77.2, 43.6 and 27.6 mg 100 ml⁻¹ in Groups 1–5, respectively. Supplementation of diet with E significantly elevated triglyceride and phospholipid concentrations in the liver; also 1% E with C (S+1%C+1%E) caused significant TC accumulation in the liver and elevated malondialdehyde concentrations in plasma and erythrocytes. In conclusion, this study demonstrates, for the first time, that evening primrose cake extract (E) possesses strong hypocholesterolemic action. Its antioxidative properties, especially in animals loaded with dietary cholesterol, are less clear and need further studies..     

Sorghum distillers dried grain lipid extract increases cholesterol excretion and decreases plasma and liver cholesterol concentration in hamsters

Grain sorghum is a rich source of phytochemicals. In this study, male hamsters were fed AIN-93M diets supplemented with a hexane-extractable lipid fraction from sorghum distillers dried grains with solubles (DDGS). Diets contained 0.0%, 0.5%, 1.0%, and 5.0% (w/w) DDGS lipid extract. After 4 wk, the 5.0% DDGS lipids group had significantly lower plasma non-HDL cholesterol and liver esterified cholesterol concentration. Faecal neutral sterol (i.e., cholesterol) excretion was significantly higher in the 5.0% DDGS lipids group compared to the other treatments (66% higher compared to controls). Bile acid excretion was not affected by DDGS lipid intake. Faecal cholesterol excretion was negatively correlated with liver cholesterol concentration (r = ?0.97, P = 0.026), and liver cholesterol concentration was directly correlated with plasma total cholesterol concentration (r = 0.96, P = 0.041). Thus, lipid extract of sorghum DDGS exhibited cholesterol-lowering properties due, at least in part, to increased cholesterol excretion from the body and could provide health benefits when incorporated into human diets.     

Antihypertensive activity of AMC3, an engineered 11S amaranth globulin expressed in Escherichia coli,in spontaneously hypertensive rats

The acidic-subunit of 11S seed storage globulin of Amaranthus hypochondriacus was recently modified by the incorporation of antihypertensive biopeptides: four units of Val–Tyr dipeptides (VY) in tandem and one of Ile–Pro–Pro tripeptide (IPP), was named AMC3. The in vivo effect of AMC3 enzymatic hydrolysates (AEH) produced in Escherichia coli, was evaluated in spontaneously hypertensive rats (SHR) by once-oral administration experiments. As positive control a SHR group received a dose of captopril (50 mg/kg) (an angiotensin-converting enzyme (ACE) inhibitor used for the treatment of hypertension). Mean arterial pressure (MAP) was measured for 6 h after AEH or captopril administration. AEH administration at maximal dose (100 mg/kg) significantly reduced MAP similar to the group treated with captopril. The maximal reduction in MAP was observed after 3.5 h after AEH oral administration. The present study showed that enzymatic hydrolysates of AMC3 containing ACE inhibitory peptides (4xVY and IPP) sequences had significant antihypertensive action by oral administration in spontaneously hypertensive rats (SHR).     

Effect of protein hydrolysates from sardinelle (Sardinella aurita) on the oxidative status and blood lipid profile of cholesterol-fed rats

This study was designed to test the hypolipidemic properties and antioxidative activities of sardinelle (Sardinella aurita) protein hydrolysates (SPHs) obtained by treatment with crude enzyme preparations from Bacillus pumilus A1(SPHA1), Bacillus mojavensis A21(SPHA21) and crude enzyme extract from sardinelle viscera (SPHEE).Wistar rats were fed during 7 weeks a standard laboratory diet, a cholesterol-enriched diet (1%) or a cholesterol SPH-enriched diet. The hypercholesterolemic diet induced the elevation of total cholesterol (TC), triglycerides (TG), and low-density lipoprotein cholesterol (LDL-C). Supplementing cholesterol-enriched diet with SPHs or whole sardinelle protein (WSP) at a concentration of 5% (w/w) increased the serum level of high-density lipoprotein cholesterol (HDL-C) and HDL-C/TC ratio and decreased the serum levels of TC, TG, LDL-C and LDL-C/HDL-C ratio significantly.The thiobarbituric acid-reactive substances (TBARS) level, as an indicator of lipid peroxidation, and the activity of superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) were examined. The hepatic antioxidant enzymes activities were significantly decreased and the malondialdehyde (MDA) level was increased in rats fed a cholesterol-enriched diet compared to those fed a standard diet. The treatment of hypercholesterolemic (HCD) diet rats with SPHs reduced the MDA concentration and increased the antioxidant enzyme activities.These results suggested that the hypolipidemic effect of SPHs might be due to their abilities to lower serum TC, TG, and LDL-C levels as well as to their antioxidant activities preventing the lipid peroxidation process.     

Antiobesity and lipid lowering effects of theaflavins on high-fat diet induced obese rats

Theaflavins are major polyphenols in black tea. This study investigated antiobesity and lipid lowering effects of black tea extract (BTE), a highly purified theaflavins mixture (TFs, 83.84%) and theaflavin (TF1, 93.25%) on high-fat diet (HFD) induced obese rats. The body weight was slightly reduced by BTE and TFs (p > 0.05), and was significantly decreased by TF1 (p < 0.05) relative to the HFD control group. All samples remarkably decreased the food intake, adiposity index and the serum levels of total cholesterol (TC), triacylglycerol (TG) and low-density lipoprotein cholesterol (LDL-C) (p < 0.05), except that BTE and TF1 insignificantly decreased the TC concentration (p > 0.05). Moreover, administration of BTE, TFs and TF1 all significantly decreased atherogenic index (AI), enhanced insulin sensitive index (ISI), inhibited the hepatic lipase (HL) activity (p < 0.05), and slightly reduced leptin level in liver, decreased serum alanine transaminase (ALT) activity and increased serum superoxide dismutase (SOD) activity (p > 0.05) as compared to that of the HFD controls. These results indicated that theaflavins were one of the functional components which contributed to the antiobesity and lipid lowering effects of black tea, and might reduce the risk of type 2 diabetes and cardiovascular disease (CVD) in obese patients.     

Effect of Lactobacillus-fermented adlay-based milk on lipid metabolism of hamsters fed cholesterol-enriched diet

The aim of this study was to investigate the effect of adlay milk and adlay-soymilk fermented with Lactobacillus plantarum or Lactobacillus paracasei on lipid metabolism in hamsters fed with a cholesterol-enriched diet. Adlay milk and fermented adlay milk with or without soymilk administered to hamsters significantly decreased (p < 0.05) serum cholesterol levels and ratio of low-density lipoprotein cholesterol to high-density lipoprotein cholesterol, when compared to a high-cholesterol diet group; there was also a significant (p < 0.05) increase in the level of fecal cholesterol and triglycerides. The group administered adlay milk fermented with L. plantarum or L. paracasei presented increased superoxide dismutase and total antioxidant status activity in the blood, thus relieving the levels of thinobarbituric acid reactive substances as compared to other treatment groups. Adlay milk and Lactobacillus-fermented adlay milk with or without a soymilk supplement, could be used as a potential cholesterol-lowering ingredient; it could also relieve hyperlipidemia-induced oxidative stress to improve hypercholesterolemia.     

Protective effect of tetrahydrocurcumin and chlorogenic acid against streptozotocin–nicotinamide generated oxidative stress induced diabetes

The present study was undertaken to investigate the protective effect of tetrahydrocurcumin (THC) and chlorogenic acid (CGA) against streptozotocin (STZ)–nicotinamide (NA)-induced type 2 diabetes in adult Wistar rats. Diabetes was induced in experimental rats weighing 180–220 g, by a single intraperitoneal (i.p.) injection of STZ (45 mg/kg BW), 15 min after the (i.p.) administration of NA (110 mg/kg BW). THC (80 mg/kg BW) and CGA (5 mg/kg BW) were orally administered to diabetic rats for a period of 45 days. Fasting plasma glucose, glycosylated haemoglobin (HbA_1C), thiobarbituric acid reactive substances (TBARS) and lipid hydroperoxides (LOOH) were significantly increased, whereas insulin, total haemoglobin (Hb), non-enzymic antioxidants (reduced glutathione (GSH), vitamin C, vitamin E and ceruloplasmin) were decreased significantly in diabetic rats. Though the diabetic rats treated with THC and CGA individual exerts beneficial effects in all the biochemical parameters in (STZ)-induced diabetic rats. The combined treatment with THC and CGA normalized all the above-mentioned biochemical parameters in STZ-induced diabetic rats. Normal pancreatic histological architecture in THC and CGA treated diabetic rats revealed that these phytochemical exert higher degree of protection when administered in combination than single treatment of individual compounds.     

Flavanoid rich ethyl acetate fraction of Musa paradisiaca inflorescence down-regulates the streptozotocin induced oxidative stress,hyperglycaemia and mRNA levels of selected inflammatory genes in rats

Musa paradisiaca inflorescence is a commonly used vegetable. The purpose of this study was to evaluate the antioxidant; hypoglycaemic and anti-inflammatory activities of flavanoid rich fraction of M. paradisiaca inflorescence (MPIF) in streptozotocin (STZ) induced diabetes mellitus. Diabetic rats were treated with MPIF (200 mg/kg body weight/day) for 60 days. Diabetic rats showed significant (p < 0.05) increase in blood glucose, HbA₁C and lipid peroxidation products (LPO) and reduction in the activities of antioxidant enzymes in liver. The activities of inflammatory markers COX-2 and 5-LOX in monocytes and mRNA expressions of NF-κB, TGF-β₁, TNF-α and IL-6 in liver were significantly (p < 0.05) increased in diabetic group. In addition, the histopathological analysis of liver showed that severe steatosis and inflammation in diabetic group. But all these parameters were significantly (p < 0.05) reduced to near normal level and restored the histopathological alterations in MPIF treated group. In addition, HPLC and ESI-MS analysis of MPIF revealed that the presence of gallic acid (4.49 g%), quercetin (1.13 g%) and epicatechin. This indicates that the supplementation of MPIF may be beneficial as food supplement for the prevention or attenuation of diabetic complications.     

Nigella sativa oil affects glucose metabolism and lipid concentrations in patients with type 2 diabetes: A randomized,double-blind,placebo-controlled trial

The aim of the present study was to determine the effects of Nigella sativa (NS) oil on glucose metabolism and lipid concentrations in patients with type 2 diabetes (T2DM). In this double-blind randomized controlled clinical trial, 72 volunteer subjects at Endocrinology Clinics of Kermanshah were recruited. Participants were patients aged 30–60 years old with T2DM. They were randomly divided into intervention (n = 36) and placebo groups (n = 36) and received 3 g/day (one three times a day) NS oil or sunflower soft gel capsules for 12 weeks. At baseline and at the end of the trial, anthropometric indices, dietary intake and biochemical parameters were measured. Sixty-seven patients completed the trial (intervention n = 34, placebo n = 33). Since the data analysis was based on intention-to-treat approach, all 72 subjects (36 in each group) were included for data analysis. Two groups were similar in the baseline characteristics. After the intervention, weight and body mass index decreased in the intervention group compared to the baseline, but it was not significant between the two groups. Dietary intake in both groups changed compared to baseline. Comparison of the two groups indicated that fasting blood sugar, glycated hemoglobin, triglyceride and low density lipoprotein–cholesterol changed significantly in intervention group compared to the placebo group (p < 0.05, adjusted for confounder factors). Insulin level and insulin resistance decreased and high density lipoprotein–cholesterol increased in the intervention group, but after adjusting for confounder factors, they were not significant. Supplementation with NS oil can improve glycemic status and lipid profile in patients with T2DM.     

Myricetin modulates streptozotocin–cadmium induced oxidative stress in long term experimental diabetic nephrotoxic rats

Oxidative stress plays a pivotal role in the development of diabetic nephropathy. The present study was aimed to evaluate the modulatory potential of myricetin on streptozotocin (STZ)–cadmium (Cd) induced oxidative stress in diabetic nephrotoxic rats. Diabetic nephrotoxicity was induced by single intraperitoneal injection of STZ at a dose of (40 mg/kg body weight (b/w)) and Cd as cadmium chloride (CdCl₂) (100 p.p.m.). Myricetin was administered to diabetic nephrotoxic rats by intraperitoneally at 1.0 mg/kg b/w for a period of 12 weeks to assess its effects on fasting plasma glucose, plasma insulin, total haemoglobin, glycosylated haemoglobin, lipid peroxidation products viz., thiobarbituric acid reactive substances (TBARS), lipid hydroperoxides (LOOH), protein carbonyl content (PCO) and non-enzymatic antioxidants namely vitamins C and E and reduced glutathione (GSH) and also enzymatic antioxidants such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST) and glutathione reductase (GR). Improvement of antioxidant status in myricetin supplemented diabetic nephrotoxic rats revealed its cellular protective effect. Histopathology of liver and kidney confirmed the protective effects of myricetin in diabetic nephrotoxic rats. The outcome of this study concludes that myricetin could be therapeutic flavonol for regulating oxidative mechanism in STZ–Cd induced diabetic nephrotoxic rats.     

Hypocholesteremic effect of bile salt hydrolase from Lactobacillus buchneri ATCC 4005

The effect of oral administration of the immobilized bile salt hydrolase enzyme on serum cholesterol, triglyceride, high density lipoprotein levels and its application in the therapeutic treatment of hypercholesteremia was assessed. Culture conditions were optimized for the production of bile salt hydrolase, which resulted in 2.9-fold enhancement in activity. Bile salt hydrolase (BSH; E.C.3.5.1.24) was isolated from Lactobacillus buchneri ATCC 4005 and immobilized in 0.5% gellan gum gel. The immobilized enzyme was orally delivered in wistar rats, induced with hypercholesteremia by triton X-100. The serum cholesterol and triglycerides were reduced by 50% and 15%, respectively, in the group fed with immobilized enzyme 10 IU/kg dose whereas administration of 20 IU/kg immobilized enzyme resulted in reduction of serum cholesterol by 58% and triglycerides by 45%, respectively. The results indicate that bile salt hydrolase has potential cholesterol lowering property and oral administration of the immobilized enzyme is an alternative pharmacological approach to reduce serum cholesterol levels.