Hormone therapy without the complications

One of the consequences of the decline in the levels of the female and male sex hormones with age is osteoporosis. Oestrogen replacement therapy can slow or prevent osteoporosis but can also have undesirable effects, for example, an increased risk of endometrial cancer.

In 9 March Cell, Stavros Manolagas and colleagues of the University of Arkansas for Medical Sciences report on the mechanism by which sex hormones protect osteoblasts from undergoing apoptosis.

Using a variety of osteoblast cell lines, they established that both oestrogens and androgens could block the effects of etoposide, dexamethasone or tumour necrosis factor-α, treatments that normally induce apoptosis (Cell 2001, 104:719-730). Furthermore, both oestrogen receptor-α and -β and the androgen receptor transmitted the anti-apoptotic signal with the same efficiency whether the ligand was an oestrogen or androgen. This finding helps explain why either class of sex hormone has been found to be equally...