The proliferative effect of tempeh in female ovariectomized rats

Hormone Replacement Therapy (HRT) is an evolving therapy for estrogen deficiency. However, the long-term use possesses side-effect such as induction to breast cancer. Genistein, a phytoestrogen compound contained in tempeh, exerts estrogenic activity. This research aims to study the effects of tempeh in uterine weight and the mammary gland proliferation of ovariectomized rat and senescence effect using in vitro model. In this study, we used Indonesian standardized (SNI) tempeh. Female rats Sprague-Dawley strain aged 7 wk to 8 wk were divided to five groups of treatment (negative, ovariectomy (OVX) baseline, positive control, OVX+tempeh 500 mg · kgBW−1, OVX+tempeh 1 000 mg · kgBW−1). Estradiol and tempeh were administered to rats for two weeks. At the end of treatment, rats were necropsied, and the uterine and breasts were isolated. Tempeh treatment did not increase uterine weight due to OVX. Haematoxylin-Eosin staining on breast tissue showed significant enhancement of lobules on OVX+tempeh 1 000 mg · kgBW−1 rat treated group compared to OVX. Moreover, AgNOR staining showed that tempeh treatment in both doses significantly increased black dots compared to OVX group. Examination of senescence by SA-β-galactosidase on CHO-K1 cells showed that treatment of tempeh 30 µg · mL−1 was not differed from control, however, at a dose of 150 µg · mL−1 tempeh significantly induced senescence. Therefore, it was concluded that tempeh has the potential to be developed as phytoestrogens in menopausal women with certain dose settings.