leptin and salvin

As postmenopausal women experience a rapid increase in cardiovascular disease (CVD) risk with an increase in abdominal fat, dietary interventions to reduce CVD risk have been emphasized. This study was aimed at investigating the effect of a high-fat diet (HFD) in combination with an ovariectomy on liver and adipose tissue fat metabolism. The efficacy of carnosic acid (CA) supplementation in the suppression of HFD- and ovariectomy-induced obesity was also evaluated. Ovariectomized (OVX) or sham-operated mice at eight weeks of age were fed with a normal diet (ND), HFD, ND and 0.02% CA, or HFD and 0.02% CA for 12 weeks. All of the animals were sacrificed at the age of 20 weeks. The blood and tissue markers of the lipogenesis and adipocyte differentiation were measured. As expected, ovariectomy decreased the uterus weight and serum 17β-estradiol concentration. The HFD and ovariectomy significantly contributed to increases in the body weight and total fat mass, which were effectively inhibited by CA supplementation. The circulating concentrations of insulin, leptin, and TG (triglyceride) were significantly higher in the HFD group, and the concentrations were two to five times higher in the OVX and HFD group compared with those of the ND group. The CA supplementation significantly lowered the insulin, leptin, and TG concentrations in the OVX and HFD mice. The hepatic protein expressions of pAMPK and pACC were up-regulated by CA supplementation in OVX mice fed either ND or HFD. The expressions of hepatic SREBP1c and FAS mRNA were the highest in the OVX and HFD group, which were suppressed by CA supplementation. The adipose tissue PPARγ, aP2, and lipoprotein lipase (LPL) mRNA expressions were up-regulated by a HFD or ovariectomy, while they were significantly reduced in the mice fed a CA supplemented diet. The TNF-α and IL-6 mRNA levels in the adipose tissue were decreased by providing CA in the OVX groups. These results suggest that HFD and ovariectomy independently contribute to body fat accumulation, and CA effectively alleviated the ovariectomy-induced increases in lipogenesis and adipocyte differentiation. Further human trials are required in order to evaluate the efficacy of rosemary-derive CA as natural anti-adipogenic compounds, especially in postmenopausal women.

Topics: Abietanes; Adipocytes; Adipogenesis; Adipose Tissue; Animals; Body Weight; Cell Differentiation; Diet; Diet, High-Fat; Dietary Supplements; Female; Insulin; Leptin; Lipogenesis; Liver; Mice, Inbred C57BL; Obesity; Ovariectomy; Phytotherapy; Plant Extracts; Postmenopause; Rosmarinus; Triglycerides

Carnosic acid (CA) and rosemary extracts (REs) have antiobesity effects but the mechanisms are not understood. We investigated some of the potential mechanisms contributing to the metabolic effects of an RE enriched in CA.. An RE (∼40% CA) was administered to lean (Le, fa/+) and obese (Ob, fa/fa) female Zucker rats for 64 days. Several adipocytokines, brain-derived neurotrophic factor, phosphorylated AMP-activated protein kinase, and hepatic gene expression changes were investigated. The RE significantly decreased circulating tumor necrosis factor alpha (RE/CT = 0.36, p < 0.0003), IL-1β (0.48, p < 0.032), and leptin (0.48, p < 0.002), and upregulated adiponectin (1.47, p < 0.045) in the Le rats. The RE also induced phase I and phase II gene expression and the peroxisome proliferator-activated receptor gamma coactivator 1-alpha. Notably, the RE decreased adipose phosphorylated AMP-activated protein kinase and did not affect hepatic peroxisome proliferator-activated receptor gamma coactivator 1-alpha in the Ob rats.. Our results show that an RE rich in CA exerts anti-inflammatory effects and affects hepatic metabolism in normal Le rats. We report significant differences in the expression and regulation of key metabolic sensors between Le and Ob rats that may contribute to explain the different ability of the two genotypes to respond to the RE.

Topics: Abietanes; Adiponectin; AMP-Activated Protein Kinases; Animals; Anti-Inflammatory Agents; Anti-Obesity Agents; Brain-Derived Neurotrophic Factor; Female; Genotype; Interleukin-1beta; Leptin; Liver; Obesity; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; Plant Extracts; Rats; Rats, Zucker; Rosmarinus; Transcription Factors; Tumor Necrosis Factor-alpha; Up-Regulation

This study determined the efficacy of carnosic acid (CA) for suppressing colon carcinogenesis associated with excess adiposity.. Cell growth regulation by CA was evaluated in HT-29 colon adenocarcinoma cells cocultured with 3T3-L1 adipocytes. To determine the in vivo efficacies, male A/J mice were divided into four groups and fed one of the following experimental diets for 11 wk: 15% fat, 45% fat, 45% fat + 0.01% CA, or 45% fat + 0.02% CA. Azoxymethane was administered at the beginning of experimental diet and two cycles of dextran sodium sulfate were supplied 1 wk after the azoxymethane injection. The proliferation of HT-29 cells cocultured with 3T3-L1 cells was significantly higher than proliferation of control cells (p < 0.05). CA treatment suppressed the growth of cocultured HT-29 cells through cell cycle arrest and enhanced apoptosis by inhibiting leptin receptor (Ob-R) signaling, including Akt and extracellular signal-regulated kinase (ERK) phosphorylation. CA supplementation in vivo decreased the number of colon tumors and reduced circulating concentrations of leptin, adiponectin, insulin, and insulin-like growth factor 1. Colonic expression of Ob-R, insulin receptor (IR), p-Akt, p-ERK, B-cell lymphoma extra large (Bcl-xL), and cyclinD1 protein was also suppressed in animals fed CA.. CA appears to alleviate adipocity-related acceleration of colon tumor formation.

Topics: 3T3-L1 Cells; Abietanes; Adipocytes; Adipogenesis; Adiponectin; Adiposity; Animals; Apoptosis; Azoxymethane; bcl-X Protein; Cell Proliferation; Colon; Colonic Neoplasms; Cyclin D1; Dextran Sulfate; Extracellular Signal-Regulated MAP Kinases; HT29 Cells; Humans; Insulin; Insulin-Like Growth Factor I; Interleukin-6; Leptin; Male; Mice; Plant Extracts; Proto-Oncogene Proteins c-akt; Receptor, Insulin; Receptors, Leptin; STAT3 Transcription Factor

Carnosic acid (CA), found in rosemary, has been reported to have antioxidant and anti-adipogenic properties. We recently demonstrated that CA protects against steatosis in ob/ob mice. In the present report, we investigated the molecular mechanism by which CA inhibits lipids accumulation both in vivo and in vitro.. In the in vivo study, ob/ob mice were fed a standard chow diet with or without CA for 5 weeks, then their hepatocyte lipid accumulation was determined. The serum concentrations of cytokines, the levels of lipid regulatory mediators, and the hepatic metabolic and signaling molecules were also evaluated. In the in vitro study, HepG2 cells were used to further clarify the effects of CA on cellular lipid accumulation and to confirm the signaling pathways involved in these effects.. CA significantly reduced hepatocyte lipid accumulation. This effect was associated with repressed levels of hepatic PPARγ, reduced expression of inflammatory cytokines such as IL-1β, IL-12, IL-17, IFN-γ, MCP-1, and MIP-1β, and increased ATP, acetyl CoA, NAD(P)(+), and NAD(P)H. Other signaling molecules, such as EGFR, MAPK, AMPK, and ACC, which regulate lipid metabolism, were activated in mice fed the CA diet. CA inhibited palmitate-induced cellular lipid accumulation and stimulated the phosphorylation of both EGFR and MAPK. Pretreatment with either the EGFR inhibitor AG1478 or the MEK-specific inhibitor U0126 abolished the effects of CA on cellular lipid accumulation and decreased both the protein expression and activity of PPARγ.. EGFR/MAPK signaling plays an important role in the inhibitory effect of CA on hepatocyte lipid accumulation.

Topics: Abietanes; Animals; Antioxidants; Cytokines; ErbB Receptors; Hep G2 Cells; Hepatocytes; Humans; Leptin; Lipid Metabolism; Male; MAP Kinase Signaling System; Mice; Mice, Obese; Phosphorylation; Plant Extracts; PPAR gamma; Signal Transduction