Efeitos do estrogênio, raloxifeno e extrato de soja rico em genisteína sobre o osso de ratas adultas ovariectomizadas previamente androgenizadas

Abstract

Não houve diferença estatística significante do PCR em tempo real na análise dos transcritos entre os grupos estudados. CONCLUSÃO: A combinação de estrogênio com raloxifeno ou extrato de soja rico em genisteína não trouxe benefícios adicionais na qualidade do tecido ósseo, como ocorreu com esses fármacos isoladamente.

Tratamento com raloxifeno induz à expressão dos receptores de kisspeptina, insulina e androgênio em ossos de ratas adultas castradas

“…Nine days after birth, the rats received testosterone propionate (0.1 mg/g), subcutaneously, in order to induce an increase in final bone mass. 6,7 After 6 months of life, the weight range observed was 278 g to 312 g. At that time, 40 rats underwent ovariectomy (►Fig. 1).…”

“…After 21 days, a colpocytological examination was carried out to prove the effect of castration. 6,7 Three months after ovariectomy, the 40 rats were randomly divided into 5 equal groups, containing 8 rats each, namely: G2-ovariectomized rats that received conjugated equine estrogens, dose of 50 µg/Kg/day; G3-ovariectomized rats that received raloxifene, 0.75 mg/kg/day; G4-ovariectomized rats that received soy extract enriched with genistein, 300 mg/kg/day; G5-ovariectomized rats that received soy extract enriched with genistein and combined estrogens; and G6-ovariectomized rats that received raloxifene and combined estrogens. These substances were administered for 120 consecutive days, with the aid of a metal probe, as previously described.…”

“…6 Castration of female rats induces a pathological process similar to that of diseases that affect the bone structure, with consequent weight gain and decreased absorption of intestinal calcium. 6,7 The experimental model that best mimics osteoporosis in postmenopausal women is obtained by performing ovariectomy in rats > 6 months old. 7,8 Aware of the relevance of estrogen in physiology and the complications of classical hormonal therapy and selective estrogen receptor modulators (SERMs), phytoestrogens have aroused great clinical interest as a therapeutic alternative.…”

“…6,7 The experimental model that best mimics osteoporosis in postmenopausal women is obtained by performing ovariectomy in rats > 6 months old. 7,8 Aware of the relevance of estrogen in physiology and the complications of classical hormonal therapy and selective estrogen receptor modulators (SERMs), phytoestrogens have aroused great clinical interest as a therapeutic alternative. These molecules show high structural and chemical similarity to estrogens.…”

“…For instance, genistein shares a structure similar to that of 17 β-estradiol, enabling it to bind to estrogen receptors (ERs) and functionally possess estrogenic and antiestrogenic activities. 6,7 Raloxifene (benzothiophene analogue) acts as a selective modulator of estrogen receptors, being used in the treatment and prevention of osteoporosis. Studies show that raloxifene increases bone density and reduces the risk of vertebrae fractures by up to 50% in women with early menopause.…”