Antilipogenic effect of green tea extract in C57BL/6J‐Lepob/ob mice

The objective of this study was to determine the effects of green tea extract (GTE) on lipid metabolism in obese animal models. Male C57BL/6J‐Lepob/ob mice were divided into control and GTE (0.05 g/100 g diet) groups, which were fed a high‐fat (20 g/100 g diet) diet for 12 weeks. Supplementation of GTE significantly reduced (p < 0.01) perirenal and total white adipose tissue weights compared with the control group. Also, the plasma HDL‐cholesterol level was significantly higher in the GTE group than in the control group, therefore the GTE group showed a higher HDL‐cholesterol/total‐cholesterol ratio (HTR) and lower atherogenic index (AI) level than the control group. A reduction of hepatic triglyceride content and adipose tissue weight in the GTE group was related to the suppression of enzyme activities for fatty acid synthesis (glucose‐6‐phosphate dehydrogenase and malic enzyme) without affecting fatty acid oxidation enzyme (β‐oxidation and carnitine palmitoyl transferase) activities in hepatic and adipose tissue. The current results showed that supplementation of green tea extract is beneficial for antiobesity by the suppression of lipogenesis via regulation of related enzyme activities in hepatic and adipose tissue. Copyright © 2008 John Wiley & Sons, Ltd.     

Effect of aqueous extract of Ajuga iva supplementation on plasma lipid profile and tissue antioxidant status in rats fed a high-cholesterol diet

The present study was designed to explore the possible antioxidant and hypolipidemic effects of the aqueous extract of Ajuga iva (0.5% in the diet) in rats fed a high-cholesterol (1%) diet (HCD). The results indicated that the HCD-Ai versus HCD treatment led to many changes in biochemical parameters. They showed a decrease of plasma total cholesterol (TC) and VLDL-cholesterol but an increase of HDL(2)-cholesterol. The triacylglycerol contents were reduced in plasma and in VLDL. The lipid peroxidation determined by TBARS was decreased by 75% in plasma. TBARS in liver, heart and kidneys were highly reduced excepted in the adipose tissue. Ajuga iva treatment enhanced superoxide dismutase activity in liver and kidney. Glutathione reductase activity was lowered in adipose tissue but increased in liver and in kidney. A significant increase was noted in glutathione peroxidase activity in liver, heart and kidney but a low value in adipose tissue was observed. In conclusion, the present study demonstrates that in addition to its potent TG and TC-lowering effects, Ajuga iva is effective in improving the antioxidant status by reducing lipid peroxidation in plasma and tissues and enhancing the antioxidant enzymes in rats fed high-cholesterol diet. Furthermore, Ajuga iva may reduce intestinal cholesterol absorption.     

Superoxide dismutase activity enhanced by green tea inhibits lipid accumulation in 3T3-L1 cells

We studied the effect of powdered green tea on intracellular superoxide dismutase activity in the adipose conversion of 3T3-L1 cells. By the 14 days of culture with insulin, the triglyceride concentration was increased. When powdered green tea and insulin were added simultaneously, the increased triglyceride content was decreased (p < 0.05), and the superoxide dismutase activities were significantly enhanced (p < 0.05). These data suggest that green tea may have an antilipogenic activity due to its radical scavenging activity mechanism.     

Anti-obesity action of Salix matsudana leaves (Part 1). Anti-obesity action by polyphenols of Salix matsudana in high fat-diet treated rodent animals

In preliminary experiments, polyphenol fractions prepared from the leaves of Salix matsudana reduced the elevation of the rat plasma triacylglycerol level at 3 and 4 h after oral administration of a lipid emulsion containing corn oil, at a dose of 570 mg/kg. The present study examined the anti-obesity action of polyphenol fractions of S. matsudana leaves by testing whether the polyphenol fractions prevented the obesity induced by feeding a high-fat diet to female mice for 9 weeks. Body weights at 2-9 weeks and the fi nal parametrial adipose tissue weights were significantly lower in mice fed the high-fat diet with 5% polyphenols of S. matsudana leaves than in those fed the high-fat diet alone. The polyphenols of S. matsudana leaves also significantly reduced the hepatic total cholesterol content, which was elevated in mice fed the high-fat diet alone. In addition, the polyphenol fractions of S. matsudana leaves inhibited palmitic acid uptake into brush border membrane vesicles prepared from rat jejunum and alpha-amylase activity, and their fractions enhanced norepinephrine-induced lipolysis in fat cells. In conclusion, it is suggested that the inhibitory effects of the flavonoid glycoside fraction of S. matsudana leaves on high-fat diet-induced obesity might be due to the inhibition of carbohydrate and lipid absorption from small intestine through the inhibition of alpha-amylase and palmitic acid uptake into small intestinal brush border membrane or by accelerating fat mobilization through enhancing norepinephrine-induced lipolysis in fat cells.     

A combination of grape extract, green tea extract and L-carnitine improves high-fat diet-induced obesity, hyperlipidemia and non-alcoholic fatty liver disease in mice

To develop a therapeutic agent for obesity-related metabolic disorders, a mixture of dietary components was prepared, including grape extract, green tea extract and l-carnitine (RGTC), and its effects on obesity, hyperlipidemia and non-alcoholic fatty liver disease examined. The RGTC dramatically inhibited the high-fat diet (HFD)-induced increase in body weight and fat in C57BL/6 mice, whereas food consumption was not affected by RGTC treatment. The RGTC also concentration-dependently suppressed the HFD-induced increase in plasma lipids, such as low-density lipoprotein cholesterol and triglycerides. In addition, increases in liver weight and liver steatosis were returned to normal by RGTC treatment in HFD-fed C57BL/6 mice. The plasma levels of glutamic-oxaloacetic transaminase and glutamic-pyruvic transaminase were also significantly down-regulated by RGTC treatment. These results suggest that RGTC suppressed HFD-induced obesity, hyperlipidemia and non-alcoholic fatty liver disease, suggesting that RGTC supplementation might be a promising adjuvant therapy for the treatment of these metabolic disorders.     

The hypolipidaemic activity of aqueous Erica multiflora flowers extract in Triton WR-1339 induced hyperlipidaemic rats: a comparison with fenofibrate

In the present study, an aqueous extract from Erica multiflora L. (Ericaceae) flowers was evaluated for its hypocholesterolaemic and hypotriglyceridaemic activities using Triton WR-1339 induced hyperlipemic rats as experimental model. Hyperlipideamia was developed by intraperitonial injection of Triton (200mg/kg body weight). The animals were divided into control (CG), hyperlipidaemic (HG), hyperlipidaemic plus herb extract (HG+EmE) and hyperlipidaemic plus fenofibrate (HG+FF) treated groups. Intragastric administration of Erica multiflora extract (0.25 g/100g body weight) to the rats caused a significant decrease on their plasma lipid levels (quantified using enzymatic kits). At 7h after treatment, plasma total cholesterol, triglycerides and LDL-cholesterol were decreased by 47%, 95% and 67%, respectively, but the change of HDL-cholesterol level was not significant. However, the hypolipidaemic effect of fenofibrate was limited to triglycerides and LDL-cholesterol, which were lowered by about 92% and 41%, respectively. At 24h after treatment, Erica multiflora extract reduced plasma total cholesterol by 68.5% and triglycerides by 91%. HDL-cholesterol was not significantly increased and LDL-cholesterol was lowered by 80.5%. In fenofibrate treated rats, only plasma triglyceride concentrations were lowered by 82%, while the other lipid parameters were not significantly changed indicating that this aqueous herb extract may contain products that lower plasma lipid concentrations and might be beneficial in treatment of hyperlipideamia.     

Effects of black tea extract on carbon tetrachloride-induced lipid peroxidation in liver, kidneys, and testes of rats

Previous studies have shown that green tea and black tea have antioxidant effects and chemopreventive activity against chronic disease including some forms of cancer. We have, therefore, examined the effects of an aqueous extract of black tea against carbon tetrachloride-induced lipid peroxidation as determined by the formation of thiobarbituric acid reactive substances in liver, kidneys and testes of rats. A 0.7% black tea extract was used which contained 2 mg of black tea extract solids per mL. Black tea was administered as drinking water for 3, 6, 9 and 12 months before and during carbon tetrachloride (CCl(4)) treatment in female and male rats. Rats were treated with a single oral dose of CCl(4) 1.0 mL/kg. All rats were killed 24 h after CCl(4) treatment. All animals were dosed with CCl(4) at the end of the 3, 6, 9, and 12 month of treatment. Black tea treatment for 75 days produced a decrease in CCl(4)-induced hepatic lipid peroxidation but significant decreases in thiobarbituric acid reactive substances occurred 3 months after treatment in both female and male rats. In liver and kidneys, black tea alone increased lipid peroxidation by 30%-50% in female and male rats. However, black tea decreased CCl(4)-induced lipid peroxidation in liver of female and male rats by approximately 49% and 37%, respectively. Black tea decreased CCl(4)-induced lipid peroxidation in testes by approximately 37% at a dose of 1.0 mL CCl(4)/kg. These results suggest that the protective effects of black tea against CCl(4)-induced lipid peroxidation in liver, kidneys and testes is due at least partly to its antioxidant properties, scavenging CCl(4)-associated free radicals.     

Regulation of obesity and lipid disorders by herbal extracts from Morus alba, Melissa officinalis, and Artemisia capillaris in high-fat diet-induced obese mice

Melissa officinalis L. (Labiatae), Morus alba L. (Moraceae), and Artemisia capillaris Thunb. (Compositae) are suggested to be involved in the regulation of hyperlipidemia. We hypothesized that Ob-X, a mixture of three herbs, Morus alba, Melissa officinalis and Artemisia capillaris [corrected] improves lipid metabolism, body weight gain and adiposity and that peroxisome proliferator-activated receptor alpha (PPARalpha) is associated with these events. Mice fed a high-fat diet for 12 weeks exhibited increases in body weight gain and adipose tissue mass compared with mice fed a low fat diet. However, feeding a high-fat diet supplemented with Ob-X significantly reduced these effects. Ob-X treatment also decreased the circulating levels of triglycerides and total cholesterol, and inhibited hepatic lipid accumulation. Ob-X supplementation was found to increase the hepatic mRNA levels of PPARalpha target enzymes responsible for fatty acid beta-oxidation. Moreover, Ob-X elevated the endogenous expression of a luciferase reporter gene containing three copies of a PPAR response element (PPRE) in NMu2Li liver cells. These data demonstrate that Ob-X regulates body weight gain, adipose tissue mass, and lipid metabolism in part through changes in the expression of hepatic PPARalpha target genes.     

蒺藜皂苷对预防小鼠高脂血症中肝脂酶和脂蛋白脂酶的作用及意义

目的:观察蒺藜皂苷(tribu saponin from Tribulus terrestris,STT)对预防小鼠高脂血症模型中脂蛋白脂酶(lipoprotein lipase,LPL)、肝脂酶(hepatic lipase,HL)活性的变化。方法:高脂膳食喂饲小鼠,并设正常对照、高脂对照、非诺贝特片阳性对照和STT高中低剂量组。测定血脂生化指标,同时检测血浆、肝组织中HL活性以及血浆、肝组织、脂肪组织和骨骼肌组织中LPL活性。结果:非诺贝特片及STT均能使肝组织中HL活性升高(P<0.01,P<0.05),STT能降低血浆中HL活性(P<0.05),而非诺贝特片组HL活性与高脂组无显著性差异(P>0.05)。肝组织中,非诺贝特片和STT能明显提高LPL活性(P<0.01,P<0.05);各组血浆中LPL活性均无明显改变(P>0.05);非诺贝特片和STT能提高骨骼肌组织中LPL活性(P<0.05),同时明显降低脂肪组织中LPL活性(P<0.01,P<0.05)和脂肪组织与肌肉组织中LPL的活性比值(P<0.01,P<0.05)。结论:STT能增加预防小鼠高脂血症模型肝组织中HL和LPL脂酶活性,降低脂肪组织与肌肉组织中LPL的活性比值,这一作用与降低血浆胆固醇水平和预防高脂血症密切相关。     

化痰祛瘀法治疗代谢综合征32例

目的:观察中医药治疗代谢综合征临床疗效。方法:用化痰祛瘀法,自拟方药治疗代谢综合征32例,观察空腹血糖(FPG)、甘油三酯(TG)、高密度胆固醇(HDL-C)以及血压水平的变化。结果:治疗前后比较,以空腹血糖和血脂水平的改善尤为显著,总有效率为84.37%。结论:化痰祛瘀法治疗该病,有一定的降血糖、减体重、降低甘油三酯及调节胆固醇的作用,并可控制高血压。     

不同茶叶及茶多酚对高脂饲料致大鼠脂肪肝的影响

目的:考察不同产地绿茶、红茶以及绿茶多酚对高脂饲料致大鼠脂肪肝的影响.方法:大鼠喂饲高脂饲料制备大鼠脂肪肝模型,喂饲含不同茶叶或茶多酚的高脂饲料,观察体重变化、睾丸脂肪垫重量、血清TG和TC、肝脏脂肪性变、肝匀浆甘油三酯和胆固醇含量.结果:各受试物组睾丸脂肪垫重量均较模型对照组减轻,云南绿茶组和四川绿茶组肝匀浆甘油三酯和胆固醇均明显低于模型对照;茶多酚组肝匀浆甘油三酯也明显低于模型对照组,但高于云南绿茶组和四川绿茶,茶多酚组肝匀浆胆固醇低于模型对照组,但明显高于云南绿茶组和四川绿茶组;云南红茶组肝匀浆甘油三酯和胆固醇与模型对照组相当.结论:云南绿茶和四川绿茶均对高脂饲料致大鼠脂肪肝的形成有明显抑制作用;茶多酚也有一定作用;但云南红茶作用不明显.     

Parkinsonia aculeata aqueous extract fraction: biochemical studies in alloxan-induced diabetic rats

The antidiabetic effect of Parkinsonia aculeata water soluble fraction (WSF) made of aerial parts of the plant (leaves and flowers) was investigated in alloxan diabetic rats. Its effect was compared with that of insulin (positive control). The physico-metabolic parameters measured were: body weight, food and liquid intake, urinary volume, hepatic glycogen, serum glucose, total cholesterol, HDL-cholesterol, triglycerides, urinary glucose and urea, and the weight of epididymal adipose tissue, liver, kidneys and the skeletal muscles (soleus and extensor digitorum longus). Oral administration of WSF (125 or 250 mg/kg) for 16 days exhibited a significant reduction in serum and urinary glucose, urinary urea, total cholesterol, HDL-cholesterol and triglycerides in alloxan diabetic rats. An improvement of hepatic glycogen, a decrease of liquid and food intake, and a significantly positive actions in the weight of skeletal muscles (soleus and extensor digitorum longus) and kidneys were also observed, but just diabetic group treated with WSF at a dose of 125 mg/kg showed significant reduction in urinary volume, body weight, an improvement of epididymal adipose tissue and a positive action in liver weight. The effects of WSF on the physico-metabolic parameters was comparable to those observed in diabetic insulin treated group. The results of this work suggest that P. aculeate may have new clinical significant choice in diabetes mellitus illness, and could explain the basis for its traditional use to manage diabetes-related complications by rural community of northeast of Brazil.     

Lutein ameliorates high-fat diet-induced obesity,fatty liver,and glucose intolerance in C57BL/6J mice

Obesity is a multi-factorial metabolic syndrome that increases the risk of cardiovascular diseases, diabetes, and cancer. We recently demonstrated the antiadipogenic efficacy of lutein using a 3 T3-L1 cell culture model. This study aimed to examine the antiobesity efficacy of lutein on high-fat (60% kcal fat) diet-induced C57BL/6J obese mice model. Lutein (300 and 500 μM), Orlistat (30 mg/kg body weight - positive control), and its combination (orlistat, 15 mg/kg body weight+lutein, 300 μM) were administered in high-fat diet (HFD)-fed mice every other day for 24 weeks. The effect on serum and hepatic lipid parameters was estimated using biochemical assay kits. The adipose tissue expression of adipocyte differentiation markers at gene and protein levels was analyzed by RT-PCR and western blotting, respectively. The results showed that lutein administration and drug significantly reduced epididymal and abdominal adipose tissue weights. Further, lutein reduced the serum cholesterol and LDL-C concentration compared to the HFD group. The HFD-induced elevation in the hepatic triglycerides and cholesterol levels were significantly blocked by lutein and its combination with the drug. Similarly, lutein and its drug combination efficiently lowered the HFD-mediated elevated blood glucose levels. Lutein downregulated the expression of CEBP-α, PPAR-γ, and FAS in the epididymal adipose tissue. Thus, supplementation of lutein may control diet-induced obesity and associated complications in the human population.     

Hypolipidemic activity and mechanism of purified herbal extract of Salvia miltiorrhiza in hyperlipidemic rats

AIM OF THE STUDY: The study aimed at evaluating the hypolipidemic effects of Purified Salvia miltiorrhiza extract (PSME) and investigating the potential molecular mechanisms by which PSME modulated lipid profiles in hyperlipidemic rats. MATERIALS AND METHODS: Sprague-Dawley male rats on a high-fat/high-cholesterol diet were treated orally with PSME, GW3965 (a selective liver X receptor agonist) or vehicle alone. Gene expression analysis and transactivation assays were used to clarify the molecular mechanisms of action of PSME. RESULTS: The concentrations of plasma total cholesterol, low-density lipoprotein cholesterol (LDL-cholesterol) and triglycerides in rats treated with PSME at 150mgkgday(-1) were significantly decreased (P<0.01), accompanied with significantly decreased concentrations of liver total cholesterol and triglycerides (P<0.01). In both drug-treated rats, the concentration of high-density lipoprotein cholesterol (HDL-cholesterol) was significantly elevated (P<0.01). Intriguingly, short heterodimer partner (SHP) mRNA level was significantly higher in PSME-treated rats (P<0.01), accompanied with the significantly decreased mRNA level of sterol regulatory element binding protein 1c (SREBP1c) (P<0.01), which contributed to the decreases of liver and plasma triglycerides through a farnesoid X receptor-SHP-SREBP1c pathway. ATP-binding Cassette Transporter B11 (ABCB11) and murine Mdr2 P-glycoprotein (also known as ABCB4) were significantly induced by PSME, which were responsible for biliary cholesterol solubility by proper biliary secretion of bile salts and phospholipids. The transactivation assays were used to identify PSME as a farnesoid X receptor/liver X receptor alpha coagonist. CONCLUSION: These results indicated that PSME as a farnesoid X receptor/liver X receptor alpha coagonist largely improved the lipid profiles in the hyperlipidemic rats.     

虎杖提取液对非酒精性脂肪肝大鼠肿瘤坏死因子α基因表达的影响

应用RT qPCR方法检测分析非酒精性脂肪肝动物模型药物干预效果.经过4周的干预试验,干预组大鼠脂肪组织的TNF-αt mRNA相对水平比对照组显著下降(t=2.452,P=0.022).干预组的肝组织甘油三酯、总胆固醇和葡萄糖含量均低于对照组,其中总胆固醇含量的差异显著(t=2.555,P=0.019).研究表明,虎杖水提液可以显著地降低NAFLD大鼠脂肪组织的TNF-α mRNA水平,也可以降低大鼠肝组织甘油三酯、总胆固醇和葡萄糖的含量,在调节肝脂、肝糖代谢和改善肝细胞脂肪变性具有一定效果.     

Hypolipedaemic activity of picroliv in albino rats

The hypolipidaemic action of picroliv, a standarized preparaton from Picrorhiza kurrooa, has been studied in normal as well as in triton- and cholesterol-fed rats. Serum lipids were found to be lowered by picroliv (25 mg/kg b.w.) in triton WR-1339-induced hyperlipaemia. Chronic feeding of this drug (6 mg/kg b.w.) in normal rats and in animals simultaneously treated with cholesterol (25 mg/kg b.w.) for 30 days caused lowering in the lipid and protein levels constituting β-lipoproteins followed by an increase in high density lipoprotein cholesterol in experimental animals. Picroliv alters lipolytic activities in plasma, liver, heart an adipose tissues and stimulated receptor mediated catabolism of low density lipoprotein. The lipid lowering action of the natural product is mediated through inhibition of cholesterol biosynthesis in liver, increased faecal bile acid excretion and enhanced plasma lecithin: cholesterol acyltransferase activity.     

Chlorogenic Acid Exhibits Cholesterol Lowering and Fatty Liver Attenuating Properties by Up‐regulating the Gene Expression of PPAR‐α in Hypercholesterolemic Rats Induced with a High‐Cholesterol Diet

Hypercholesterolemia is a major risk factor for the development of cardiovascular disease and nonalcoholic fatty liver disease. Natural compounds have been proved to be useful in lowering serum cholesterol to slow down the progression of cardiovascular disease and nonalcoholic fatty liver disease. In the present study, the hypocholesterolemic and hepatoprotective effects of the dietary consumption of chlorogenic acid were investigated by monitoring plasma lipid profile (total cholesterol, triglycerides, high‐density lipoprotein and low‐density lipoprotein) in Sprague–Dawley rats fed with a normal diet, a high‐cholesterol diet or a high‐cholesterol diet supplemented with chlorogenic acid (1 or 10 mg/kg/day p.o.) for 28 days. Chlorogenic acid markedly altered the increased plasma total cholesterol and low‐density lipoprotein but decreased high‐density lipoprotein induced by a hypercholesterolemic diet with a dose‐dependent improvement on both atherogenic index and cardiac risk factor. Lipid depositions in liver were attenuated significantly in hypercholesterolemic animals supplemented with chlorogenic acid. It is postulated that hypocholesterolemic effect is the primary beneficial effect given by chlorogenic acid, which leads to other secondary beneficial effects such as atheroscleroprotective, cardioprotective and hepatoprotective functions. The hypocholesterolemic functions of chlorogenic acid are probably due to the increase in fatty acids unitization in liver via the up‐regulation of peroxisome proliferation‐activated receptor α mRNA. Copyright © 2012 John Wiley & Sons, Ltd.     

Plasma lipid-lowering and lipogenesis-stimulating actions of ginseng saponins in tumor-bearing rats

Ascited hepatoma (AH41C or AH130) was transplanted to male rats Donryu strain. Plasma cholesterol, triglyceride (TG) and non-esterified fatty acid levels were reduced with oral administration of ginseng principle fraction 3 (saponin content, ca. 1/5). Incorporation of 1-[14C]-acetate into total lipids and fatty acids in adipose tissue was increased by fraction 3 administration in both normal and tumor-bearing rats. The incorporation increased in the earlier stage of tumor growth and decreased in the later one. Incorporation of 1-[14C]-acetate into total lipid, free and esterified cholesterol, TG and phospholipid in the liver was also enhanced by fraction 3 administration in both normal and tumor-bearing animals. In vitro addition of ginseng principle fraction 4 (saponin content, ca. 1/2) increased incorporation of 1-[14C]-acetate into lipid fractions in adipose tissue and liver. Incorporation of 1-[14C]-acetate into lipid fractions in ascites hepatoma cells remained unchanged with both oral administration of fraction 3 and in vitro addition of fraction 4. DNA and protein synthesis in the tumor cells was not changed with in vitro addition of fraction 4.     

Therapeutic role of Cuminum cyminum on ethanol and thermally oxidized sunflower oil induced toxicity

Ethanol is one of the most widely used and abused drugs, increasing lipid levels in humans and experimental animals. Heating of oil rich in polyunsaturated fatty acids (PUFA) produces various lipid peroxidative end products that can aggravate the pathological changes produced by ethanol. In the present communication, the effect of Cuminum cyminum was investigated on alcohol and thermally oxidized oil induced hyperlipidaemia. The results showed increased activity of aspartate transaminase (AST), alkaline phosphatase (ALP) and gamma glutamyl transferase (GGT) and increased levels of cholesterol, triglycerides and phospholipids in the plasma of rats given alcohol, thermally oxidized oil and alcohol+thermally oxidized oil when compared with the normal control group. The levels of tissue (liver and kidney) cholesterol and triglycerides were increased significantly in rats groups given alcohol, thermally oxidized oil and alcohol+thermally oxidized oil when compared with the normal control rats. The levels were decreased when cumin was given along with alcohol and thermally oxidized oil. The level of phospholipids decreased significantly in the liver and kidney of groups given alcohol, thermally oxidized oil and alcohol+thermally oridized oil when compared with the normal control rats. The level increased when cumin was administered along with alcohol and thermally oxidized oil. The activity of phospholipase A and C increased significantly in the liver of groups given alcohol, thermally oxidized oil and alcohol+thermally oxidized oil when compared with the normal control rats, whereas the activity was decreased with the cumin treatment. The results obtained indicate that cumin can decrease the lipid levels in alcohol and thermally oxidized oil induced hepatotoxicity.