Osteoporosis, estrogens

RIGGS B L, KHOSLA s and MELTON L J, 111 (1998) A Unitary model for involutional osteoporosis estrogen deficiency causes both type 1 and type 11 osteoporosis in postmenopausal women and contributes to bone loss in aging men. J Bone Min Res 13, 16 i-l i. 

Age, calcium intake, hormonal status, exercise and vitamin status have all been implicated in the development of osteoporosis. Estrogen levels represent an important factor in skeletal calcium retention and homeostasis. In therapeutic trials in which post-menopausal women were given daily doses of estrogens, such therapy has been demonstrated to be partially effective in reducing the rate of bone resorption. However, this therapy has the concomitant hazard of endometrial cancer (10). Vitamin D and its hormones have been given considerable attention in the more recent studies. Without adequate dietary and tissue levels of such vitamins, calcium absorption and bone status will be impaired. 

Osteoporosis — estrogen by itself or with hypercalcemic steroid is used in the treatment of osteoporosis. 

The most frequent uses of estrogens are for contraception (see p. 268), for postmenopausal hormone therapy and for osteoporosis. Estrogens are also used extensively for replacement therapy in patients deficient in this hormone. Such a deficiency can be due to lack of development of the ovaries, menopause, or castration. 

The major clinical effects of estrogen deficiency are coronary heart disease and osteoporosis. Estrogen supplements in postmenopausal women have been directed mainly at slowing the process of osteoporosis. Nevertheless, atherosclerotic heart disease is the leading cause of death in women, accounting for more than 30%... 

Estrogens Decreased estrogens are probably responsible for postmenopausal osteoporosis. Estrogens increase renal la-hydroxylase activity. Promotes osteoblast differentiation. 

Heterocycles as synthetic estrogens in emerging therapies for the prevention or treatment of postmenopausal osteoporosis 99JMC1. 

Estrogens and progestins are diminished in menopausal or ovarectomized women. In hormone replacement therapy (HRT), these hormones are substituted to alleviate hot flushes, mood changes, sleep disorders, and osteoporosis. 

It has been shown that in postmenopausal women habitually high intakes of dietary isoflavones are associated with higher bone mineral density (BMD) values at both the spine and hip region (Mei et al, 2001). It is conceivable that an isoflavone-rich diet may help to reverse the state of secondary hyperparathyroidism associated with estrogen withdrawal and hence lower the rate of bone turnover in postmenopausal women, thus reducing the risk of osteoporosis (Valtuena et al, 2003). Phytoestrogens could be used as natural SERMs (Brzezinski and Debi, 1999) and some studies (Setchell, 2001 and refs therein) support such an idea since the molecular targets of... 

Several Grignard reactions are used on an industrial scale in drug synthesis.95 The syntheses of both tamoxifen and droloxifene, which are estrogen antagonists used in treatment of breast cancer and osteoporosis, respectively, involve Grignard addition... 

The prolonged suppression of estrogen in pre-menopausal women with hyperprolactinemia leads to decreases in bone mineral density and significant risk for the development of osteoporosis. 

Estrogen currently is indicated for the treatment of moderate to severe vasomotor symptoms and vulvovaginal atrophy associated with menopause. In addition, it is indicated for the prevention of postmenopausal osteoporosis in women with significant risk however, it is recommended that non-estrogen medications receive consideration for long-term use. Oral or transdermal estrogen products should be prescribed at the lowest... 

---