gamma-sitosterol and Body-Weight

Hyperglycemia is a major public health problem worldwide and there is increasing demand for prevention of postprandial hyperglycemia in diabetic, prediabetic, and healthy humans.. We investigated whether rice bran and triterpene alcohol and sterol preparation (TASP) lowered hyperglycemia in mice and humans. Brown rice and white rice supplemented with TASP lowered the postprandial hyperglycemia in humans. TASP and its components (cycloartenol [CA], 24-methylene cycloartanol, β-sitosterol, and campesterol) decreased postprandial hyperglycemia in C57BL/6J mice. Glucose transport into everted rat intestinal sacs and human HuTu80 cells transfected with sodium-glucose cotransporter-1 (SGLT1) was significantly reduced by the addition of CA. Intracellular localization analysis suggested that SGLT1 translocation to the apical plasma membrane was inhibited when the cells were treated with CA.. We demonstrated for the first time that TASP from rice bran lowered postprandial hyperglycemia in mice and humans. The smaller increase in blood glucose following TASP consumption may be due to the CA-induced decrease in glucose absorption from the intestine, which may be related to decreased membrane translocation of SGLT1.

Topics: Adult; Animals; Blood Glucose; Body Mass Index; Body Weight; Cell Line, Tumor; Cholesterol; Dietary Fiber; Humans; Hyperglycemia; Insulin; Male; Mice; Mice, Inbred C57BL; Oryza; Phytosterols; Rats; Rats, Wistar; Single-Blind Method; Sitosterols; Sodium-Glucose Transporter 1; Sterols; Triterpenes

High doses of soy protein are able to decrease plasma cholesterolemia significantly, but they unbalance daily protein intake and strongly modify nutritional habits in patients.. To evaluate the antihypercholesterolemic efficacy of a low dose soy protein product with added beta-sitosterol (rapport = 4:1) in 36 moderately hypercholesterolemic subjects.. The study was divided into 3 separate periods of 40 days each: a stabilization diet period, followed by a treatment period during which all subjects took 10 g of the test product once daily and, finally, a wash out period. The following parameters were monitored: weight, dietary habits, plasma lipid levels, glycemia, uric acid, fibrinogenemia and antibodies against oxidized LDL (ox-LDL Ab).. From the end of the stabilization diet period to the end of the supplementation with the soy protein product with added beta-sitosterol we observed a 19.64 +/- 20.32 mg/dL, 8.47 +/- 54.61 mg/dL, 1.69 +/- 10.92 mg/dL, and 7.06 +/- 16.66 mg/dL mean +/- SD decrease respectively in LDL-C (p < 0.001), TG (p = 0.358), VLDLs (p = 0.358) and apoB (p = 0.016) levels, associated with a 1.31 +/- 8.08 mg/dL and 1.03 +/- 19.09 mg/dL mean increase respectively in HDLC (p = 0.251) and apoAI (p = 0.749) plasma concentrations. The dietary supplementation did not influence Lp(a) (p = 0.984) and ox-LDL Ab (p = 0.953) plasma levels. A statistically significant correlation was observed for LDL-C plasma levels, between the end of the stabilization diet period and the end of the period of supplementation with soy proteins with added beta-sitosterols (p < 0.001).. Although further long-term clinical studies are necessary before claims can be made regarding the therapeutic effects of the tested formulation, the preliminary findings regarding its efficacy and safety as an antihypercholesterolemic agent are encouraging.

Topics: Anticholesteremic Agents; Body Weight; Cholesterol; Cholesterol, HDL; Cholesterol, LDL; Dose-Response Relationship, Drug; Feeding Behavior; Female; Humans; Hypercholesterolemia; Lipid Peroxidation; Male; Middle Aged; Sitosterols; Soybean Proteins; Treatment Outcome; Triglycerides

Our aim was to test the hypocholesterolemic effect of a low-dose formulation of soy proteins supplemented with isolated b-sitosterol in a ratio of 4:1 in 20 moderately hypercholesterolemic subjects. The study has been divided in three different periods of forty days each: a stabilization diet period, then a treatment period during which all subjects assumed 10 g one time a day of the tested product and, finally, a wash out period. From the end of the stabilization diet period to the end of the soy protein added in b-sitosterol supplementation we observed a 0.45 +/- 0.30 mmol/L, 0.09 +/- 0.31 mmol/L and 0.17 +/- 0.22 mmol/L mean +/- SE decrease in respectively LDL-C, TG and apoB levels, associated with a 0.12 +/- 0.25 and 0.03 +/- 0.51 mg/dL mean increase respectively in HDL-C and apoA plasma concentrations. According to this recommends, low doses of soy protein added in b-sitosterol seems to be a practical and safe alternative for patients seeking modest reductions in LDL-C (< 15%).

Topics: Apolipoproteins A; Body Weight; Cholesterol, LDL; Female; Humans; Hypercholesterolemia; Hypolipidemic Agents; Linear Models; Male; Middle Aged; Sitosterols; Soybean Proteins

Oil-based products enriched with plant stanol esters can lower low-density lipoprotein (LDL) cholesterol concentrations by 10-14%. Effectiveness of low-fat products, however, has never been evaluated, although such products fit into a healthy diet. We therefore examined the effects of plant stanol esters emulsified into low-fat yoghurt (0.7% fat) on fasting concentrations of plasma lipids and lipid-soluble antioxidants, which may also change by plant stanol consumption. Sixty non-hypercholesterolemic subjects first consumed daily three cups (3 x 150 ml) of placebo yoghurt for 3 weeks. For the next 4 weeks, 30 subjects continued with the placebo yoghurt, while the other 30 subjects received three cups of experimental yoghurt. Each cup provided 1 g of plant stanols (0.71 g sitostanol plus 0.29 g campestanol) as its fatty acid ester. LDL cholesterol (mean+/-S.D.) increased by 0.06+/-0.21 mmol/l in the placebo group, but decreased by -0.34+/-0.30 mmol/l in the experimental group. The difference in changes between the two groups of 0.40 mmol or 13.7% was highly significant (P<0.001; 95% confidence interval for the difference, (-)0.26 -(-)0.53 mmol/l). Effects were already maximal after 1 week. HDL cholesterol and triacylglycerol concentrations did not change. Total tocopherol levels increased by 1.43 micromol/mmol LDL cholesterol (14.0%, P=0.015). beta-carotene levels, however, decreased by -0.02 micromol/mmol LDL cholesterol (-14.4%, P=0.038). Decreases in absolute beta-carotene concentrations were found in all apoB-containing lipoproteins. LDL-cholesterol standardised phytofluene levels decreased by 21.4+/-25.7% (P<0.001), while other plasma carotenoid (lutein/zeaxanthin, beta-cryptoxanthin, lycopene and alpha-carotene) levels did not change significantly. We conclude that low-fat yoghurt enriched with plant stanol esters lowers within 1 week LDL cholesterol to the same extent as oil-based products. LDL-cholesterol standardised concentrations of tocopherol increased. The observed decrease in beta-carotene levels, as found in many other studies, appears not to be limited to the LDL fraction.

Topics: Adolescent; Adult; Aged; Antioxidants; Body Weight; Cholesterol; Diet, Fat-Restricted; Double-Blind Method; Female; Humans; Intestinal Mucosa; Lipids; Lipoproteins; Male; Middle Aged; Netherlands; Phytosterols; Plants; Sitosterols; Solubility; Stigmasterol; Yogurt

Treatment with carbamazepine (CBZ) affects cholesterol concentrations, but little is known about the precise nature and underlying mechanisms of changes in lipoprotein metabolism. We investigated prospectively the effects of CBZ on lipid metabolism in normolipemic adults. In 21 healthy males, lipoprotein and noncholesterol sterol concentrations were measured before and during treatment with CBZ for 70 +/- 18 days. Thirteen subjects underwent kinetic studies of apolipoprotein-B (ApoB) metabolism with the use of endogenous stable isotope labeling. Lipoprotein kinetic parameters were calculated by multicompartmental modeling. Significant increases in total cholesterol, in ApoB-containing lipoproteins [very-low-density lipoprotein (VLDL), intermediate density lipoprotein (IDL), and low-density lipoprotein (LDL)], and in triglycerides, but not in high-density lipoprotein (HDL), were observed. Lipoprotein particle composition remained unchanged. Mean fractional catabolic and production rates of ApoB-containing lipoproteins were not significantly different, although mean production rates of VLDL and IDL were substantially increased (+46 +/- 139% and +30 +/- 97%, respectively), whereas mean production of LDL remained unchanged (+2.1 +/- 45.6%). Cholestanol in serum increased significantly but not the concentrations of plant sterols (campesterol, sitosterol) and the cholesterol precursors (lathosterol, mevalonic acid). There was a significant correlation between the decrease in free thyroxine and the increase in IDL cholesterol. Treatment with CBZ increases mainly ApoB-containing lipoproteins. CBZ seems not to influence endogenous cholesterol synthesis or intestinal absorption directly. The increase is neither related to increased ApoB production nor to decreased catabolism but is rather due to changes in the conversion cascade of IDL particles, most likely as an indirect effect through a decrease in thyroid hormones.

Topics: Adult; Anticonvulsants; Arteriosclerosis; Body Composition; Body Weight; Carbamazepine; Cholestanol; Cholesterol; Cholesterol, HDL; Cholesterol, LDL; Cholesterol, VLDL; Diet; Humans; Hydrocortisone; Intestinal Absorption; Lipoproteins; Male; Mevalonic Acid; Phytosterols; Sitosterols

Coronary patients with low baseline ratios of serum cholestanol and plant sterols to cholesterol (indicating low cholesterol absorption) but not those with high ratios (high absorption) experienced reduced recurrences of coronary events during simvastatin treatment in the Scandinavian Simvastatin Survival Study. Thus, in the present study, serum cholesterol, its precursor sterols (reflecting cholesterol synthesis), plant sterols (campesterol and sitosterol), and cholestanol were measured before and during a 5-year period of placebo treatment (n=433) and simvastatin treatment (n=434) in patients from a subgroup of the Scandinavian Simvastatin Survival Study to determine whether changes in cholesterol synthesis and serum levels were related to cholesterol absorption. Serum cholesterol level was unchanged, the ratios of cholesterol precursor sterols to cholesterol were decreased, and the ratios of plant sterols to cholesterol were increased in relation to increasing baseline ratios of cholestanol quartiles. The latter predicted 5-year ratios and simvastatin-induced reductions of the precursor sterols, with the lowering of the ratios (cholesterol synthesis reduction) being almost twice higher in the lowest versus the highest quartile. The ratios of plant sterols, especially campesterol, to cholesterol were markedly increased during simvastatin treatment, mostly in subjects with the highest baseline cholestanol quartiles. Simvastatin reduced serum cholesterol more (P=0.003) in the lowest versus the highest cholestanol quartile during the 5-year treatment period. The results show for the first time that baseline cholesterol metabolism, measured by serum noncholesterol sterols, predicts the effectiveness of simvastatin in reducing cholesterol synthesis and serum levels of cholesterol. The drug suppresses the synthesis of cholesterol markedly more effectively in subjects with high than with low baseline synthesis but reduces respective serum cholesterol levels less markedly than synthesis. Subjects with high cholesterol absorption and low synthesis may need a combination therapy to lower more effectively their serum cholesterol levels and prevent an increase in the levels of plant sterols.

Topics: Anticholesteremic Agents; Body Weight; Cholestanol; Cholesterol; Coronary Disease; Desmosterol; Humans; Phytosterols; Placebos; Simvastatin; Sitosterols; Sterols

Climate change has become the global concern due to its drastic effects on the environment. Agriculture sector is the backbone of food security which remains at the disposal of climate change. Heat stress is the is the most concerning effect of climate change which negatively affect the plant growth and potential yields. The present experiment was conducted to assess the effects of exogenously applied β-sitosterol (Bs at 100 mg/L) and eucalyptus biochar (Eb at 5%) on the antioxidants and nutritional status in Thymus vulgaris under heat stressed conditions. The pot experiment was conducted in completely randomize design in which thymus plants were exposed to heat stress (33 °C) and as a result, plants showed a substantial decline in morpho-physiological and biochemical parameters e.g., a reduction of 59.46, 75.51, 100.00, 34.61, 22.65, and 38.65% was found in plant height, shoot fresh weight, root fresh weight, dry shoot weight, dry root weight and leaf area while in Bs + Eb + heat stress showed 21.16, 56.81, 67.63, 23.09, 12.84, and 35.89% respectively as compared to control. In the same way photosynthetic pigments, transpiration rate, plant nutritional values and water potential increased in plants when treated with Bs and Eb in synergy. Application of Bs and Eb significantly decreased the electrolytic leakage of cells in heat stressed thymus plants. The production of reactive oxygen species was significantly decreased while the synthesis of antioxidants increased with the application of Bs and Eb. Moreover, the application Bs and Eb increased the concentration of minerals nutrients in the plant body under heat stress. Our results suggested that application of Bs along with Eb decreased the effect of heat stress by maintaining nutrient supply and enhanced tolerance by increasing the production of photosynthetic pigments and antioxidant activity.

Topics: Agriculture; Antioxidants; Body Weight; Thymus Plant

β-sitosterol (SIT), the most abundant bioactive component of vegetable oil and other plants, is a highly potent antidiabetic drug. Our previous studies show that SIT controls hyperglycemia and insulin resistance by activating insulin receptor and glucose transporter 4 (GLUT-4) in the adipocytes of obesity induced type 2 diabetic rats. The current research was undertaken to investigate if SIT could also exert its antidiabetic effects by circumventing adipocyte induced inflammation, a key driving factor for insulin resistance in obese individuals. Effective dose of SIT (20 mg/kg b.wt) was administered orally for 30 days to high fat diet and sucrose induced type-2 diabetic rats. Metformin, the conventionally used antidiabetic drug was used as a positive control. Interestingly, SIT treatment restores the elevated serum levels of proinflammatory cytokines including leptin, resistin, tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) to normalcy and increases anti-inflammatory adipocytokines including adiponectin in type 2 diabetic rats. Furthermore, SIT decreases sterol regulatory element binding protein-1c (SREBP-1c) and enhances Peroxisome Proliferator-activated receptor-γ (PPAR-γ) gene expression in adipocytes of diabetic rats. The gene and protein expression of c-Jun-N-terminal kinase-1 (JNK1), inhibitor of nuclear factor kappa-B kinase subunit beta (IKKβ) and nuclear factor kappa B (NF-κB) were also significantly attenuated in SIT treated groups. More importantly, SIT acts very effectively as metformin to circumvent inflammation and insulin resistance in diabetic rats. Our results clearly show that SIT inhibits obesity induced insulin resistance by ameliorating the inflammatory events in the adipose tissue through the downregulation of IKKβ/NF-κB and c-Jun-N-terminal kinase (JNK) signaling pathway.

Topics: Adipocytes; Adipokines; Adipose Tissue; Animals; Body Weight; Cytokines; Diabetes Mellitus, Type 2; Diet, High-Fat; Down-Regulation; Feeding Behavior; I-kappa B Kinase; Inflammation; Inflammation Mediators; Insulin Resistance; Male; MAP Kinase Signaling System; Molecular Docking Simulation; NF-kappa B; Obesity; PPAR gamma; Rats; RNA, Messenger; Sitosterols; Sterol Regulatory Element Binding Protein 1; Sucrose; Up-Regulation

The hypolipidemic effect of phytosterols has been wildely recognized, but its application is limited due to its insolubility in water and low solubility in oil. In this study, β-sitosterol ester with linoleic acids and β-sitosterol self-microemulsions were prepared and their hypolipidemic effects on hyperlipidemia mice were studied.. Firstly, the mice were randomly divided into normal group and model group,they were fed with basic diet and high-fat diet for 70 days respectively. After high-fat model mice was successfully established, the model group was further divided into eight groups: HFD (high-fat diet feeding), SELA-TSO(8 ml/kg, SELA:700 mg/kg), TSO (8 ml/kg), SSSM (8 ml/kg,SS:700 mg/kg), NLSM (8 ml/kg), SSHT-TSO (8 ml/kg, SS: 700 mg/kg) and SS-TSO (8 ml/kg, SS: 700 mg/kg) groups, and treated with β-sitosterol ester with linoleic acid, β-sitosterol self-microemulsion, commercial β-sitosterol health tablets and β-sitosterol powder for 35 days, respectively, and blank control groups were established. At the end of the treatment period, the blood lipid level, tissues, cholesterol and lipids in feces of mice in each group were investigated. Statistical and analytical data with SPSS 17.0 Software,statistical significance was set at p* < 0.05 and p** < 0.01 levels .. The order of lowering blood lipid effect is listed as: SSSM> SELA-TSO > SSHT-TSO > SS-TSO, which shows that β-sitosterolself-microemulsion have the highest treatment effect among the experimental groups.. In this study, a new formulation of β-sitosterol was developed, and its hypolipidemic effect was investigated. The results showed that β-sitosterol self-microemulsion has a good blood lipid lowering effect.

Topics: Administration, Oral; Animals; Body Weight; Eating; Emulsions; Feces; Hyperlipidemias; Hypolipidemic Agents; Linoleic Acid; Lipids; Male; Mice; Microscopy, Electron, Transmission; Organ Size; Sitosterols; Tablets

Bombax ceiba is used traditionally to treat bone disorders, rheumatism, and joint pain. The aim of the study is to carry out osteogenic activity in-vitro and anti-osteoporotic activity in-vivo of stem bark of B. ceiba in surgical ovariectomy model in female rats.. Plant drug: B. ceiba stem bark was extracted with solvents petroleum ether and methanol using Soxhlet extraction. In-vitro osteoblastic proliferation study was performed using UMR-106 cell lines. Both the extracts were undergone to acute toxicity study as per OECD423 guidelines. Female Wistar albino rats 180-240 g were used (n = 6). Surgical ovariectomy was performed under anesthesia to induce bone porosity and loss in all animals except normal control and sham control. Each extract was administered at two dose level: 100 and 200 mg/kg and the standard Raloxifene was given at 1 mg/kg orally for 28 days. The phytochemical study of both the extracts was performed using HPLC and HPTLC.. A significant osteoblast cell proliferation and alkaline phosphatase activity were observed with B. ceiba extracts in UMR-106 cell lines. Surgical removal of ovaries produced significant (p < 0.05) decline in bone mineral density, bone breaking strength, serum ALP, calcium, phosphorus, and estradiol level and marked bone tissue destruction in histology. Administration of petroleum ether and methanolic extract for 28 days significantly (p < 0.05) ameliorated the consequences of ovariectomy induced bone porosity and restored the normal architecture of bone, as compared to OVX control. The phytochemical screening of both the extracts were also carried out. The quantification of phytoconstituents showed the presence of β-sitosterol and lupeol in petroleum ether extract, whereas the lupeol is also quantified in the methanolic extract. The presence of gallic acid was quantified in methanolic extract using HPLC.. B. ceiba: stem bark ameliorated the state of bone fragility and fracture possibly due to estrogenic modulation, as also confirmed by in-vitro osteogenic activity which may be due to the presence of lupeol, gallic acid and β-sitosterol constituents of the plant.

Topics: Animals; Body Weight; Bombax; Cell Proliferation; Chromatography, High Pressure Liquid; Chromatography, Thin Layer; Female; Gallic Acid; Osteoblasts; Osteoporosis; Ovariectomy; Pentacyclic Triterpenes; Plant Extracts; Rats; Rats, Wistar; Sitosterols

Hyperlipidemia characterized of elevated serum lipid levels is a prevalent disease frequently resulting in cardiovascular disease (CVD). Berberine and evodiamine are herbal products of traditional Chinese herb Coptis chinensis and Evodia rutaecarpa, which are indicated to exert regulation of lipid metabolism. Therefore, the objective of this study was to investigate the lipid-lowering effect of berberine and evodiamine combination in hyperlipidemic rats.. The rat model of hyperlipidemia was established by providing high-fat-diet (HFD) for 4 weeks. Berberine (BB), evodiamine (EV), and their combination (BB + EV) were orally administered to HFD induced rats for 4 weeks. Body weight, food utilization, histopathology of liver tissues, lipid profiles of serum and liver were measured. Gas chromatography (GC) analysis was applied to examine the level of plasma total cholesterol and ß- Sitosterol (BS) to estimate cholesterol absorption activity. Furthermore, intestinal NPC1L1, ACAT2, and ApoB48 protein expressions were evaluated by immunohistochemical assay.. According to the results, decreased levels of serum cholesterol (TC), triglycerides (TG), low density lipoprotein-cholesterol (LDL-C), as well as hepatic TC were showed in hyperlipidemic rats treated by combination of berberine and evodiamine. GC analysis indicated that the elevated plasma BS was significantly ameliorated by BB, EV, and BB + EV. In addition, immunohistochemical analysis revealed that BB + EV treatment down-regulated the expressions of intestinal NPC1L1 and ACAT2, and ApoB48 in HFD induced rats.. Based on the above results, combination of berberine and evodiamine exerted a promising preventive effect on hyperlipidemia, partially through inhibiting intestinal absorption of cholesterol.

Topics: Administration, Oral; Animals; Apolipoprotein B-48; Berberine; Body Weight; Cholesterol, LDL; Coptis; Diet, High-Fat; Drug Combinations; Evodia; Gene Expression Regulation; Hyperlipidemias; Hypolipidemic Agents; Intestinal Absorption; Lipid Metabolism; Liver; Male; Membrane Transport Proteins; Quinazolines; Rats; Rats, Sprague-Dawley; Sitosterols; Sterol O-Acyltransferase; Sterol O-Acyltransferase 2; Triglycerides

Laetia suaveolens, known as "casinga-cheirosa", crude extract EB719 has previously shown cytotoxic activity against prostate cancer and squamous cell carcinoma. For the first time, seven molecules were isolated from its apolar-α-tocopherol (1) and sitosterol (2)-and polar-3-O-caffeoylquinic acid (3), 4-O-caffeoylquinic acid (4), 5-O-feruloylquinic acid (5), hyperoside (6), and isoquercitrin (7)-fractions. Acute toxicity was determined in a two-stage experiment: (1) a reduced number of Balb-c male mice received 5000 mg/kg of EB719 to allow evaluation of general activity and other 27 parameters, plus death, up to the establishment of non-lethal dose (NLD), as well as lethal dose 50% (LD50); (2) NLD was administered and diazepam introduced as reference drug. EB719 showed LD50=178.0 mg/kg, and NLD 156.3 mg/kg. In stage one EB719 did not influence general activity, but provoked impairment in grasp reflexes, tail squeeze and breathing; piloerection and cyanosis were increased. In stage two, alterations occurred in auricular reflex, piloerection and breathing after diazepam administration, but not in response to EB719. Intestinal hemorrhage caused by local bleeding was observed after necropsy, and may be the main cause of animals' death other than a systemic effect of the extract. Although the isolated compounds are biologically and pharmacologically active in both men and animal systems, it is premature to relate their occurrence in EB719 to the observed intestine hemorrhage in mice.

Topics: alpha-Tocopherol; Animals; Body Weight; Diazepam; Gastrointestinal Hemorrhage; Humans; Lethal Dose 50; Male; Mice; Mice, Inbred BALB C; Organ Size; Piloerection; Plant Extracts; Quercetin; Quinic Acid; Respiration; Salicaceae; Sitosterols

β-Sitosterol has been shown to have antidiabetic and antioxidant effects in animal models. The objective of the study is to investigate the effects of β-sitosterol on insulin sensitivity, oxidative and nitrosative stress and lipid abnormalities in liver of high fat-fed rat model of insulin resistance (IR) and to assess whether nitric oxide (NO) is involved in its action. Adult male albino Wistar rats of body weight 150-180g were fed either control diet (CON) or high fat diet (HFD). Each dietary group was divided into two and treated or untreated with β-sitosterol (10mg/kgb.w.(-1)day(-1)) for 4weeks. Inhibition of total nitric oxide synthase (NOS) by administration of nitro-l-arginine methyl ester (L-NAME) and inducible NOS (iNOS) by aminoguanidine (AG) in HFD and HFD+ β-sitosterol groups were accomplished to identify the role of NO. After 28days, assays were performed in plasma and liver. HFD-fed rats showed hyperglycemia, hyperinsulinemia, IR, oxidative damage, nitrosative stress, lipid accumulation and elevated serum aminotransferases. Increased expression of iNOS and decreased expression of endothelial NOS (eNOS) were observed in them. Hepatic fat accumulation was further confirmed by histology. The biochemical and histological abnormalities associated with HFD feeding were significantly reduced by β-sitosterol administration. Administration of L-NAME to HFD-fed rats caused decrease in insulin sensitivity and increase in oxidative stress. Co-administration of L-NAME for the last seven days to β-sitosterol-treated HFD rats abolished the glucose lowering effect of β-sitosterol, but the ability to decrease oxidative stress remained unaltered. On the other hand, administration of AG resulted in improved glucose homeostasis and antioxidant levels but decreased oxidative stress and enhanced antioxidant potential in both HFD and HFD+ β-sitosterol treated groups. Thus, β-sitosterol promotes insulin sensitivity in rats fed HFD possibly by improving NO levels. With additional studies, β-sitosterol might be used as a functional drug or as an adjuvant in the management of IR and associated fatty liver disease.

Topics: Analysis of Variance; Animals; Blood Glucose; Body Weight; Diet, High-Fat; Guanidines; Hepatocytes; Insulin; Insulin Resistance; Lipid Metabolism; Liver; Male; NG-Nitroarginine Methyl Ester; Nitric Oxide; Nitric Oxide Synthase Type III; Nitrites; Organ Size; Oxidative Stress; Rats; Rats, Wistar; Sitosterols

The use of medicinal plants has turned out to be an alternative method for the treatment of diseases, such as diabetes mellitus. The recommendation of the World Health Organization Committee on Diabetes encouraging research on hypoglycemic agents of plant origin used in traditional medicine has greatly motivated research in this area. The hypoglycemic activity of Ipomoea digitata tuber extract was investigated in streptozotocin-induced diabetic rats.. An oral administration of the hydroalcoholic extract of I. digitata tuber (100 and 200 mg/kg) and glibenclamide was given for 28 days. Blood glucose levels were measured at 0, 2, 4, 6, and 24 h in the acute study and at 0, 7, 14, 21, and 28 days in the chronic study. The weight of rats was recorded before and after the study period of 28 days.. In the acute study, both doses of the extract showed a significant reduction in the blood glucose level compared with the control but less significant than glibenclamide. In the chronic study, all treatments showed a significant blood glucose reduction in diabetic rats. The extract and glibenclamide not only prevented a further body weight loss but also maintained the body weight during the study period.. The result of the study concluded that I. digitata exhibits a considerable hypoglycemic activity, which could be due to the presence of flavonoids and β-sitosterol as active principles, although the mechanism of action remains to be determined. Thus, the plant can be the key contributor in the treatment of diabetes as an alternative medicine.

Topics: Administration, Oral; Animals; Blood Glucose; Body Weight; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 2; Dose-Response Relationship, Drug; Flavonoids; Glyburide; Hypoglycemic Agents; Ipomoea; Plant Extracts; Rats; Rats, Wistar; Sitosterols; Streptozocin; Time Factors

In the present study, the efficacy of β-sitosterol isolated from an n-butanol extract of the seeds of the plant Moringa oleifera (Moringaceae) was examined against ovalbumin-induced airway inflammation in guinea pigs. All animals (except group I) were sensitized subcutaneously and challenged with aerosolized 0.5% ovalbumin. The test drugs, β-sitosterol (2.5mg/kg) or dexamethasone (2.5mg/kg), were administered to the animals (p.o.) prior to challenge with ovalbumin. During the experimental period (on days 18, 21, 24 and 29), a bronchoconstriction test (0.25% acetylcholine for 30s) was performed and lung function parameters (tidal volume and respiration rate) were measured for each animal. On day 30, blood and bronchoalveolar lavaged fluid were collected to assess cellular content, and serum was collected for cytokine assays. Lung tissue was utilized for a histamine assay and for histopathology. β-sitosterol significantly increased the tidal volume (V(t)) and decreased the respiration rate (f) of sensitized and challenged guinea pigs to the level of non-sensitized control guinea pigs and lowered both the total and differential cell counts, particularly eosinophils and neutrophils, in blood and bronchoalveolar lavaged fluid. Furthermore, β-sitosterol treatment suppressed the increase in cytokine levels (TNFα, IL-4 and IL-5), with the exception of IL-6, in serum and in bronchoalveolar lavaged fluid detected in model control animals. Moreover, treatment with β-sitosterol protected against airway inflammation in lung tissue histopathology. β-sitosterol possesses anti-asthmatic actions that might be mediated by inhibiting the cellular responses and subsequent release/synthesis of Th2 cytokines. This compound may have therapeutic potential in allergic asthma.

Topics: Acetylcholine; Animals; Anti-Asthmatic Agents; Asthma; Body Weight; Bronchial Spasm; Bronchoalveolar Lavage Fluid; Bronchoconstriction; Cell Count; Cytokines; Disease Models, Animal; Guinea Pigs; Histamine; Inflammation; Lung; Male; Ovalbumin; Respiratory System; Sitosterols; Th2 Cells

Lippia nodiflora L. (Verbenaceae) is a creeping perennial herb widely used in traditional system of medicine to treat ulcers, bronchitis and heart diseases; it also possesses antidiabetic property. In the present study, γ-sitosterol isolated from Lippia nodiflora was screened for its antidiabetic property in streptozotocin (STZ) induced diabetic rats. Insulin secretion in response to glucose was evaluated in isolated rat islets. Oral administration of γ-sitosterol (20 mg/kg body weight) once daily for 21 days in STZ-induced diabetic rats resulted in a significant decrease in blood glucose and glycosylated hemoglobin with a significant increase in plasma insulin level, body weight and food intake. Furthermore γ-sitosterol showed antihyperlipidemic activity as evidenced by significant decrease in serum total cholesterol, triglycerides and very low density lipoprotein-cholesterol levels coupled with elevation of high density lipoprotein-cholesterol levels in treated rats. A significant decrease in the activities of alanine aminotransaminase, aspartate aminotransaminase, alkaline phosphatase and acid phosphatase in γ-sitosterol treated rats when compared to diabetic control rats indicated its protective role against liver damage. γ-Sitosterol increased insulin secretion in response to glucose. Immunohistochemical study of pancreas also confirmed the biochemical findings. These results indicated that γ-sitosterol, the compound isolated from L. nodiflora, possessed antihyperglycemic activity.

Topics: Animals; Biomarkers; Blood Glucose; Body Weight; Carbohydrate Metabolism; Diabetes Mellitus, Experimental; Fasting; Glycated Hemoglobin; Glycogen; Hypoglycemic Agents; Insulin; Insulin Secretion; Lipid Metabolism; Lippia; Liver; Male; Muscles; Rats; Rats, Wistar; Sitosterols

Phytosterols or plant sterols (PS) are consumed as natural remedies and margarines by the general population in developed countries to lower elevated serum cholesterol levels. They are also present in high concentrations in pulp mill effluents. The aim of the study was to screen the endocrine and metabolic parameters of the European polecat (Mustela putorius) for the effects of PS. The results showed an increase in the plasma estradiol and TH levels with no effects on the hypophyseal regulatory hormones. The plasma ghrelin levels decreased. PS also affected intermediary metabolism. The liver glycogen content increased as did the kidney glucose-6-phosphatase activity. The liver lipase esterase activity, on the other hand, decreased due to PS. In serum lipids the total cholesterol did not change, but the low-density lipoprotein levels increased and the high-density lipoprotein-cholesterol ratio decreased. PS had widespread previously unreported effects on the physiology of the polecat. The multiple effects indicate the need of a thorough risk assessment of the effects and interactions of PS.

Topics: Animals; Body Weight; Carnivora; Dose-Response Relationship, Drug; Endocrine Glands; Estradiol Congeners; Estrogens, Non-Steroidal; Female; Glycogen; Hormones; Hypolipidemic Agents; Inactivation, Metabolic; Isoflavones; Kidney; Lipids; Liver; Male; Metabolism; Organ Size; Phytoestrogens; Phytosterols; Plant Preparations; Sitosterols

This study was designed to clarify the mechanisms of hypocholesterolemic action of beta-lactoglobuline tryptic hydrolysate (LTH) and to identify the novel hypocholesterolemic peptide derived from LTH by screening using Caco-2 cells and animal studies. Serum and liver cholesterol levels were significantly lower in rats fed LTH than in those fed casein tryptic hydrolysate (CTH). The present study suggests that the inhibition of micellar solubility of cholesterol which causes the suppression of cholesterol absorption by a direct interaction between cholesterol mixed micelles, and LTH in the jejunal epithelia is part of the mechanism underlying the hypocholesterolemic action of LTH. Though no one could trace the hypocholesterolemic peptide to any protein origin, we identified, for the first time, a novel hypocholesterolemic peptide, Ile-Ile-Ala-Glu-Lys (IIAEK). Surprisingly, the present study provides the first direct evidence that a new hypocholesterolemic peptide derived from beta-lactoglobuline can powerfully influence serum cholesterol levels and exhibit a greater hypocholesterolemic activity in comparison with that of medicine, beta-sitosterol, in animal studies.

Topics: Administration, Oral; Animals; Anticholesteremic Agents; Body Weight; Caco-2 Cells; Caseins; Cattle; Cholesterol; Chromatography, High Pressure Liquid; Feces; Food Deprivation; Humans; Jejunum; Lactoglobulins; Liver; Male; Micelles; Milk; Organ Size; Peptide Fragments; Peptides; Protein Hydrolysates; Rats; Rats, Wistar; Sitosterols; Taurocholic Acid

Various man-made agents like pesticides, industrial chemicals and some natural substances have the potential to alter hormonal pathways that regulate reproductive processes in certain species of wildlife. Until now, only a few investigations have been undertaken to determine the effects of these substances on reproductive capacities (fecundity and fertility) in exposed invertebrate aquatic species. In this study one of the most abundant mollusc of European limnic systems, the hermaphroditic gastropod Lymnaea stagnalis was investigated to determine the effects of endocrine modulating substances on reproductive parameters. Known endocrine modulating substances were tested using the following nominal concentrations; Tributyltin (TBT in ng Sn/l) and beta-sitosterol at 1, 10 and 100 ng/l, respectively, and 4-nonylphenol (4-NP) at 1, 10 and 100 microg/l. In addition, experiments were carried out with 1, 10 and 100 ng/l of t-methyltestosterone. All the testing was carried out on recently matured adults of Lymnaea. Fifteen to twenty snails per treatment were exposed for between 7 and 12 weeks in a semi-static test with a weekly exchange of testwater. Shell height and weight and mortality of the adults, egg production, hatching rate of the eggs, and histopathology of the adult snails were analysed. The same parameters were investigated on F(1) generation snails from exposed parents at two dates (1 week after exposure and at the end of the exposure duration). Treatments with TBT and 4-NP had only slight effects on the egg production of the adults and hatching rate of the eggs. However, increased histopathological changes were observed in epithelial tissues of the adult snails, e.g. lung and foot also characterised by extreme inflammatory processes. While beta-sitosterol and t-methyltestosterone had no effect on the shell height and weight or the mortality of adult snails nor on the egg production or ensuing egg hatching rate, beta-sitosterol treated snails presented a distinct atrophy of the albumen gland and so did t-methyltestosterone, albeit with a lower degree of atrophy. The observed histopathological effects due to exposure to tributyltin or 4-NP are suggested to lead to long-term adverse reproductive effects mediated by an impairment of the fitness of the snails. In the experiments the steroid-dependant (beta-sitosterol and t-methyltestosterone) degeneration of the albumen gland caused no obvious adverse effects on the fecundity nor fertility of the adults o

Topics: Animals; Body Weight; Fertility; Lymnaea; Methyltestosterone; Phenols; Reproduction; Sitosterols; Time Factors; Trialkyltin Compounds

The dietary effect of phytosterols (PS) versus cholesterol on the growth and metastasis of the PC-3 human prostate cancer cells in SCID mice was studied. Also, their direct effect on the growth and migration of these cells in vitro was analysed. In the in vivo experiment, SCID mice were fed a diet containing 2% of either PS mixture or cholesterol plus 0.2% cholic acid and implanted with 2 x 10(6) tumour cells per mouse. Tumour growth was monitored for 8 weeks post inoculation. Animals fed the PS diet had tumours 40-43% smaller than those fed the cholesterol diet. Furthermore, the number of mice with lymph node and lung metastasis was almost one-half that of the cholesterol-fed group. In the in vitro studies, both beta-sitosterol and campesterol inhibited the growth of PC-3 cells by 70% and 14%, respectively, while cholesterol supplementation increased the growth by 18% when compared with controls. PS inhibited the invasion of PC-3 cells into Matrigel-coated membranes by 78% while cholesterol increased it by 43% as compared with the cells in the control media. Migration of tumour cells through 8 microm pore membranes was reduced by 60-93% when the PC-3 cells were in PS media, as compared with a 67% increase after cholesterol supplementation. PS supplementation reduced the binding of PC-3 cells to laminin by 15-38% and fibronectin by 23% while cholesterol increased binding to type IV collagen by 36%. It was concluded that PS indirectly (in vivo as a dietary supplement) and directly (in tissue culture media) inhibited the growth and metastasis of PC-3 cells. beta-Sitosterol was more effective than campesterol in offering this protection in most of the parameters studied.

Topics: Animals; Body Weight; Cell Adhesion; Cholesterol; Humans; Male; Mice; Mice, SCID; Models, Animal; Neoplasm Metastasis; Phytosterols; Prostatic Neoplasms; Sitosterols; Tumor Cells, Cultured

Rapeseed oil fed to 24 hypercholesterolemic patients (50 g/day) reduced serum cholesterol (-8.5%) and cholestanol concentrations but increased those of campesterol and sitosterol. Continuation of rapeseed oil alone or with added sitosterol (625 mg/day) or sitostanol (630 mg/day) had no further effect on serum cholesterol. Rapeseed oil with sitosterol increased further its own proportion to cholesterol in serum but reduced that of campesterol while rapeseed oil with sitostanol reduced the proportions of both sitosterol and campesterol proportionately to the pretreatment values. The changes in the campesterol and sitosterol proportions were negatively and positively related to each other during the sitosterol and sitostanol additions, respectively. Thus, concentrations of unsaturated plant sterols in serum reflect their dietary intakes, saturated plant sterols are virtually not absorbed, plant sterols interfere with absorption of unsaturated structurally different plant sterols and cholestanol, and plant sterol-induced reduction of sterol absorption may be positively related to absorption efficiency of sterols.

Topics: Adult; Body Weight; Brassica; Cholesterol; Dietary Fats; Female; Humans; Hypercholesterolemia; Male; Middle Aged; Phytosterols; Plant Oils; Sitosterols

In two inbred strains of rabbits with high or low response of plasma cholesterol to dietary saturated versus polyunsaturated fatty acids, the efficiency of intestinal cholesterol absorption was measured. The feeding of a cholesterol-free purified diet containing saturated fatty acids in the form of coconut fat, when compared with a diet containing corn oil as polyunsaturated fatty acids, did not influence the efficiency of cholesterol absorption in the two rabbit strains. Irrespective of the dietary fat source, the hyperresponsive rabbits absorbed cholesterol more efficiently. It is concluded that the hypercholesterolemic effect of dietary coconut fat versus corn oil is not exerted by influencing cholesterol absorption.

Topics: Animals; Body Weight; Cholesterol; Cholesterol, Dietary; Coconut Oil; Cocos; Corn Oil; Dietary Fats; Feeding Behavior; Hypercholesterolemia; Intestinal Absorption; Liver; Male; Plant Oils; Rabbits; Sitosterols; Species Specificity

Chronic administration of beta-sitosterol subcutaneously to rats for 60 days was well tolerated and there was no clear cut evidence of any gross or microscopic lesions either in the liver or kidney. Liver and kidney function tests were assessed by determining the blood/serum parameters like haemoglobin, blood glucose, serum protein, serum bilirubin, serum cholesterol, serum GPT and serum GOT. All the parameters were in the normal range except serum protein and serum cholesterol. Serum cholesterol was the only variable which depleted markedly in both sexes in a dose-dependent manner suggesting intrinsic hypocholesterolemic effect of the sterol.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Bilirubin; Blood Glucose; Body Weight; Cholesterol; Dose-Response Relationship, Drug; Drug Administration Schedule; Female; Hemoglobins; Kidney; Liver; Male; Organ Size; Rats; Rats, Inbred Strains; Sex Characteristics; Sitosterols

Diosgenin and beta-sitosterol (1% in diet) were administered to CRJ:CD-1 male mice for 15 days, in order to examine the changes in bile acid metabolism. There were some differences between diosgenin and beta-sitosterol in their effects on diet intake, liver weight, and plasma cholesterol level. However, both phytosterols caused no statistically significant changes in body weight gain, decreased cholesterol absorption to about one-third that observed in control mice, decreased liver cholesterol level, increased fecal excretion of cholesterol, and decreased fecal excretion of bile acids. Most of the increase in fecal excretion of cholesterol occurred 2 days after the start of feeding of phytosterols and gradually declined thereafter, but the levels on day 15 were nevertheless higher than those in the control mice. The fecal excretion of bile acids decreased progressively after the treatment with phytosterols. The decrease of bile acid derived from chenodeoxycholic acid was more predominant than the decrease of those derived from cholic acid, resulting in an increase of the cholic acid/chenodeoxycholic acid ratio. The biliary cholesterol, phospholipid, and bile acid mole % ratios and the lithogenic index were not changed, but the percentages of cholic acid and its related bile acids (the cholic acid group) to the total bile acids increased and those of the chenodeoxycholic acid group decreased after the treatments. The pool size of bile acids decreased in the mice given diosgenin but not in those given beta-sitosterol. Distribution of bile acids between the gallbladder and intestine was not altered by either phytosterol.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Animals; Bile; Bile Acids and Salts; Body Weight; Cholesterol; Diet; Diosgenin; Feces; Kinetics; Liver; Male; Mice; Mice, Inbred Strains; Sapogenins; Sitosterols

Effects of spinasterol and sitosterol on plasma and liver cholesterol levels and biliary and fecal sterol and bile acid excretions were examined with male mice. Both phytosterols were added to the diet at a 1% concentration and fed to mice for 15 days. Spinasterol increased the fecal cholesterol excretion and decreased the plasma and liver cholesterol levels, the bile acid pool size and the fecal bile acid excretion, especially those derived from chenodeoxycholic acid. Fecal coprostanol excretion remained unchanged. These changes were similar to those produced by sitosterol. These data led to the conclusions 1) that spinasterol, as well as sitosterol, inhibits cholesterol absorption, resulting in decreases of the plasma and liver cholesterol levels and 2) that when cholesterol absorption is inhibited, the synthesis of bile acids, especially that of chenodeoxycholic acid, decreases, suggesting that the dietary cholesterol is preferentially metabolized to chenodeoxycholic acid in mice.

Topics: Animals; Bile; Bile Acids and Salts; Body Weight; Cholesterol; Feces; Liver; Male; Mice; Phospholipids; Phytosterols; Sitosterols; Sterols; Stigmasterol

Outbred male Sprague-Dawley CD rats were fed a complete semisynthetic diet and were given supplemental low doses (2 ppm) of selenium as H2SeO3 in their drinking water or 50 mg 13-cis-retinoic acid (13-cis-RA) and 2 g beta-sitosterol/kg diet either singly, in combinations of two, or in combinations of all three. Intestinal tumors were induced with eight weekly sc injections of 8 mg azoxymethane (AOM)/kg body weight, and inhibition of tumor formation was determined by tumor counts after 26 weeks. Noncarcinogen controls for each dietary group received eight injections of sterile water. Tumor inhibition was statistically significant in 2 groups of animals: Dietary control animals had a tumor frequency of 5.07 tumors/rat, rats receiving selenium- plus 13-cis-RA supplementation had a tumor frequency of 3.77, and those being given the combination of all three inhibitors had 2.75 tumors/rat. Analysis of fecal steroids from 3 AOM groups (dietary controls, the beta-sitosterol plus 13-cis-RA-supplemented group, and the group receiving all three additives) after 4 months of supplementation showed that the addition of beta-sitosterol to the diet had no effect on acidic or neutral steroids, regardless of the observed difference in tumor frequency. These results suggest that subpharmacologic doses of inhibitors, particularly those that inhibit the process by different mechanisms, while ineffective alone, may provide significant inhibition of tumorigenesis when used in combination.

Topics: Animals; Azo Compounds; Azoxymethane; Body Weight; Drinking; Eating; Intestinal Neoplasms; Male; Rats; Rats, Inbred Strains; Selenium; Sitosterols; Tretinoin

The effect of feeding 20 g beta-sitosterol/kg alone or in combination with cholestyramine (20 g/kg) during neonatal life of guinea-pigs on their subsequent response to a dietary cholesterol challenge in adult life was examined. 2. beta-Sitosterol pretreated animals showed higher plasma cholesterol values following 2 weeks on a cholesterol challenge (2-5 g/kg) diet, but did not differ significantly from control values for the remainder of the cholesterol challenge period. 3. Guinea-pigs pretreated with beta-sitosterol plus cholestyramine, on the other hand, showed a marked increase in plasma cholesterol levels over those of controls during the cholesterol challenge period, and this "hyper-responder" behaviour was maintained throughout the study period. 4. Despite the increase in plasma cholesterol, beta-sitosterol plus cholestyramine pretreated animals excreted significantly (P less than 0.05) greater amounts of bile acids and total sterols. 5. These findings demonstrate that neonatal pretreatment with beta-sitosterol plus cholestyramine has detrimental effects on the handling of a cholesterol challenge in adult life, and does not achieve the beneficial effect previously noted with pretreatment with cholestyramine alone.

Topics: Animals; Animals, Newborn; Bile Acids and Salts; Body Weight; Cholesterol; Cholesterol, Dietary; Cholestyramine Resin; Diet; Feces; Guinea Pigs; Male; Sitosterols; Sterols