Anti-Menopausal Effect of Heat-Killed HDB7040 via Estrogen Receptor-Selective Modulation in MCF-7 Cells and Ovariectomized Rats.

Menopause is induced by spontaneous ovarian failure and leads to life quality deterioration with various irritating symptoms. Hormonal treatment can alleviate these symptoms, but long-term treatment is closely associated with breast and uterine cancer, and stroke. Therefore, developing alternative therapies with novel anti-menopausal substances and improved safety is needed. In our study, heat-killed HDB7040 significantly promoted MCF-7 cell proliferation in a dose-dependent manner under estrogen-free conditions, similar to 17β-estradiol. This strain also triggered expression, but not , in MCF-7 cells. Moreover, administrating HDB7040 to ovariectomized (OVX) Sprague-Dawley (SD) female rats reduced estrogen deficiency-induced weight gain, fat mass, blood triglyceride, and total cholesterol levels. It also recovered collapsed trabecular microstructure by improving trabecular morphometric parameters (bone mineral density, bone volume per tissue volume, trabecular number, and trabecular separation) and decreasing blood alkaline phosphatase levels with no significant changes in uterine size and blood estradiol. HDB7040 also significantly regulated the expression of , , and , but not in uteri of OVX rats. Heat-killed HDB7040 exerts an anti-menopausal effect via the specific regulation of ERβ in vitro and in vivo, suggesting its potential as a novel substance for improving and treating menopausal syndrome.