Dataset Information

Mechanisms underlying the metabolic actions of galegine that contribute to weight loss in mice.

ABSTRACT: Galegine and guanidine, originally isolated from Galega officinalis, led to the development of the biguanides. The weight-reducing effects of galegine have not previously been studied and the present investigation was undertaken to determine its mechanism(s) of action.Body weight and food intake were examined in mice. Glucose uptake and acetyl-CoA carboxylase activity were studied in 3T3-L1 adipocytes and L6 myotubes and AMP activated protein kinase (AMPK) activity was examined in cell lines. The gene expression of some enzymes involved in fat metabolism was examined in 3T3-L1 adipocytes.Galegine administered in the diet reduced body weight in mice. Pair-feeding indicated that at least part of this effect was independent of reduced food intake. In 3T3-L1 adipocytes and L6 myotubes, galegine (50 microM-3 mM) stimulated glucose uptake. Galegine (1-300 microM) also reduced isoprenaline-mediated lipolysis in 3T3-L1 adipocytes and inhibited acetyl-CoA carboxylase activity in 3T3-L1 adipocytes and L6 myotubes. Galegine (500 microM) down-regulated genes concerned with fatty acid synthesis, including fatty acid synthase and its upstream regulator SREBP. Galegine (10 microM and above) produced a concentration-dependent activation of AMP activated protein kinase (AMPK) in H4IIE rat hepatoma, HEK293 human kidney cells, 3T3-L1 adipocytes and L6 myotubes.Activation of AMPK can explain many of the effects of galegine, including enhanced glucose uptake and inhibition of acetyl-CoA carboxylase. Inhibition of acetyl-CoA carboxylase both inhibits fatty acid synthesis and stimulates fatty acid oxidation, and this may to contribute to the in vivo effect of galegine on body weight.

SUBMITTER: Mooney MH

PROVIDER: S-EPMC2438274 | biostudies-other | 2008 Apr

REPOSITORIES: biostudies-other

ACCESS DATA

Similar Datasets

Project description:The metabolic impact of the common peroxisome proliferator-activated receptor gamma isoform 2 (PPARÎ³2) variant Pro12Ala in human populations has been widely debated. We demonstrate using a Pro12Ala knock-in model that on chow Ala/Ala mice are leaner, have improved insulin sensitivity and plasma lipid profiles, and longer lifespan. Gene-environment interactions played a key role as high-fat feeding eliminated the beneficial effects of the Pro12Ala variant on adiposity, plasma lipids, and insulin sensitivity. The underlying molecular mechanisms involve changes in cofactor interaction and adiponectin signaling. Altogether, our results establish the Pro12Ala variant of PparÎ³2 as an important modulator in metabolic control that strongly depends on the metabolic context. PparÎ³ Pro12Ala and wild-type littermates were fed regular rodent chow or high-fat diet (D12330, 5560 kcal/kg, Research Diets, New Brunswick, NJ), as indicated. Only males were used to minimize possible effects of variation in estrus status of females. Since the body weight development of Pro/Ala heterozygote mice was intermediate to that of Pro/Pro and Ala/Ala mice, we focused on the two homozygote genotypes in further experimentation. Mice were housed with a 12h light-dark cycle and had free access to water and food. Eight week old male Pro/Pro and Ala/Ala littermate mice were fed either regular rodent chow or high-fat diet (as above) for 15 weeks (n = 8-10 per group), at which time blood and tissue samples were collected. Total RNA extraction, sample amplification, labeling, and microarray (Genechip Mouse Genome 430 2.0 Array, Affymetrix Inc., Santa Clara, CA) processing steps were performed by the Rosetta Inpharmatics Gene Expression Laboratory (Seattle, WA) using custom automated procedures in compliance with manufacturer protocols. Microarray data was processed using Rosetta Resolver (Rosetta Inpharmatics, Seattle, WA) and expressed as relative to the virtual pool of HFD â Pro/Pro group (mlratio). Gene expression signatures were generated from these mlratios for expressed genes (25% of RMA processed intensities above 60% quantile) by T-testing (Pro/Pro vs. Ala/Ala) and correcting for multiple testing (20% cut-off for False Discovery Rate). GSEA was performed according to provider suggestions, Pro/Pro vs. Ala/Ala. Statistical significance was declared if P < 0.05.

Dataset Information

Mechanisms underlying the metabolic actions of galegine that contribute to weight loss in mice.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure