Curcuma comosa reduces visceral adipose tissue and improves dyslipidemia in ovariectomized rats

Ethnopharmacological relevance: Curcuma comosa Roxb. (C. comosa) or Wan chak motluk Zingiberaceae family, is widely used in Thai traditional medicine for treatment of gynecological problems as well as relief of postmenopausal symptoms. Since C. comosa contains phytoestrogen and causes lipid lowering effect by an unknown mechanism, we investigated its effect on adiposity and lipid metabolism in estrogen-deprived rats. Materials and methods: Adult female rats were ovariectomized (OVX) and received daily doses of either a phytoestrogen from C. comosa [(3R)-1,7-diphenyl-(4E,6E)-4,6-heptadien-3-ol; DPHD], C. comosa extract, or estrogen (17 beta-estradiol; E2) for 12 weeks. Adipose tissue mass, serum levels of lipids and adipokines were determined. In addition, genes and proteins involved in lipid synthesis and fatty acid oxidation in visceral adipose tissue were analyzed. Results: Ovariectomy for 12 weeks elevated level of serum lipids and increased visceral fat mass and adipocyte size. These alterations were accompanied with the up-regulation of lipogenic mRNA and protein expressions including LXR-alpha, SREBP1c and their downstream targets. OVX rats showed decrease in proteins involved in fatty acid oxidation including AMPK-alpha and PPAR-alpha in adipose tissue, as well as alteration of adipokines; leptin and adiponectin. Treatments with E2, DPHD or C. comosa extract in OVX rats prevented an increase in adiposity, down-regulated lipogenic genes and proteins with marked increases in the protein levels of AMPK-alpha and PPAR alpha. These findings indicated that their lipid lowering effects were mediated via the suppression of lipid synthesis in concert with an increase in fatty acid oxidation. Conclusions: C. comosa exerts a lipid lowering effect in the estrogen deficient rats through the modulations of lipid synthesis and AMPK-alpha activity in adipose tissues, supporting the use of this plant for health promotion in the post-menopausal women.