RESUMO
Impaired lipid metabolism is an important health problem in postmenopausal women with insufficient estrogens, because dyslipidemia is a risk factor for development of atherosclerosis and the incidence of cardiovascular disease markedly increases after menopause. Pueraria mirifica (PM), a Thai herb, has been noticed as a source of phytoestrogens, estrogen-mimicking plant compounds. However, the clinical effects of PM on lipid metabolism and the underlying molecular mechanisms remain undetermined. Therefore, we examined the effects of PM on serum lipid parameters in a randomized, double-blind, placebo-controlled clinical trial. Nineteen postmenopausal women were randomly assigned to receive oral administration of PM powder or placebo. After 2 months of treatment, the PM group showed a significant increase in serum concentrations of high-density lipoprotein (HDL) cholesterol and apolipoprotein (apo) A-1 (34% and 40%, respectively), and a significant decrease in low-density lipoprotein (LDL) cholesterol and apo B (17% and 9%, respectively), compared with baseline measurements. Moreover, significant decreases were observed in the ratios of LDL cholesterol to HDL cholesterol (37%) and apo B to apo A-1 (35%). Next, we determined the effects of PM phytoestrogens on the activation of estrogen receptor (ER)-mediated transactivation by transient expression assays of a reporter gene in cultured cells. Among PM phytoestrogens, miroestrol and coumestrol enhanced both ERalpha- and ERbeta-mediated transactivation, whereas other phytoestrogens, including daidzein and genistein, preferentially enhanced ERbeta-mediated transactivation. In conclusion, PM has a beneficial effect on lipid metabolism in postmenopausal women, which may result from the activation of gene transcription through selective binding of phytoestrogens to ERalpha and ERbeta.
Assuntos
Dislipidemias/tratamento farmacológico , Fitoestrógenos/farmacologia , Fitoestrógenos/uso terapêutico , Pós-Menopausa , Pueraria , Receptores de Estrogênio/agonistas , Animais , Células Cultivadas , Chlorocebus aethiops , Método Duplo-Cego , Dislipidemias/genética , Dislipidemias/metabolismo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Modelos Biológicos , Fitoestrógenos/isolamento & purificação , Placebos , Pós-Menopausa/efeitos dos fármacos , Isoformas de Proteínas/agonistas , Isoformas de Proteínas/metabolismo , Isoformas de Proteínas/fisiologia , Pueraria/química , Receptores de Estrogênio/metabolismo , Receptores de Estrogênio/fisiologiaRESUMO
AIM: The purpose of this study was to examine the effects of copper supplementation on lipid profiles in elderly patients with copper deficiency. METHODS: Nine long-term bed-ridden, patients (5 men and 4 women, mean age 83.3+/-8.7 years old) with severe copper deficiency, who had a serum copper of 15 microg/dL or less (normal range 70-140 microg/dL), had their diets supplemented with copper sulfate (3 mg/day) over 12 weeks in addition to their diet of only one kind of enteral food with a low concentration of copper. Copper, ceruloplasmin, total cholesterol (TC), triacylglycerides (TG), HDL-cholesterol (HDL-C), c-reactive protein (CRP), creatinine (Cr), zinc (Zn) and albumin (Alb) in the serum were measured before, 4 weeks and 12 weeks after copper supplementation. RESULTS: Serum copper and ceruloplasmin were significantly increased at 4 weeks after copper supplementation. TG was significantly increased at 4 weeks after copper supplementation, but at 12 weeks the increase of TG was not significant. TC, HDL-C, CRP, Cr, Zn and Alb were not changed by copper supplementation. CONCLUSION: TG was transiently increased by copper supplementation in elderly patients with copper deficiency. TC and HDL-C were not changed by copper supplementation.