The need for tissue selective menopausal agents

Tibolone as Hormonal Therapy and Neuroprotective Agent

Tibolone (TIB), a selective tissue estrogenic activity regulator (STEAR) in clinical use by postmenopausal women, activates hormonal receptors in a tissue-specific manner. Estrogenic activity is present mostly in the brain, vagina, and bone, while the inactive forms predominate in the endometrium and breast. Conflicting literature on TIB's actions has been observed. While it has benefits for vasomotor symptoms, bone demineralization, and sexual health, a higher relative risk of hormone-sensitive cancer has been reported. In the brain, TIB can improve mood and cognition, neuroinflammation, and reactive gliosis. This review aims to discuss the systemic effects of TIB on peri- and post-menopausal women and its role in the brain. We suggest that TIB is a hormonal therapy with promising neuroprotective properties.

Equol production capability is associated with favorable vascular function in postmenopausal women using tibolone; no effect with soy supplementation

OBJECTIVE

Equol, a gut bacterial metabolite of isoflavone daidzein, may improve health through changes in vascular function and in estrogen metabolism. Tibolone, a synthetic steroid alternative for the treatment of postmenopausal symptoms, causes a different estrogenic milieu than estrogen and may affect vascular health. We studied the effects of equol production and soy supplementation on vascular function in postmenopausal women under long-term tibolone use.

METHODS

We screened 110 women using tibolone for 3-60 months for high equol production capacity with a one-week soy challenge. Twenty women with high equol production capacity (4-fold elevation in equol level) and 20 comparable control women without this capacity were treated in a randomized placebo-controlled cross-over trial with a soy drink (52 g of soy protein containing 112 mg of isoflavones) or placebo for 8 weeks. Arterial stiffness and endothelial function were assessed before and after soy and placebo supplementation with pulse-wave analysis.

RESULTS

Prior to soy supplementation arterial stiffness, expressed as augmentation index, was lower (p=0.01) in equol producers (25.9+/-1.1%) than non-equol producers (29.6+/-0.9%). Similarly, endothelial function index was better at baseline (p=0.009) in these women (72.3+/-5.3%) compared to women lacking equol production capacity (55.2+/-3.8%). Soy supplementation had no effect on arterial stiffness or endothelial function in either group.

CONCLUSION

In postmenopausal tibolone users, endogenous equol production capability is associated with favorable vascular function. This phenomenon was not affected by soy and thus, equol producing capacity may be an independent vascular health marker, at least in postmenopausal women using tibolone.