Pharmacokinetic profile of equol in the combination of 70% ethanolic extract dayak onion bulbs (Eleutherine bulbosa (mill.) urb) and cowpea (vigna unguiculata (l.) walp.) and their effect on postmenopause syndrome

Alternative therapies for postmenopausal conditions are needed because of the high risks that outweigh the benefits of using hormone replacement therapy. Equol is metabolized from daidzein and is well-known as a supplement for postmenopausal conditions. Lately, liquiritigenin is also known to have a good effect on postmenopausal conditions. The aim of this study was to note the effect of the combination of Eleutherina bulbosa 70% Ethanol Extract (EEB) containing daidzein and Vigna unguiculata (EVU) containing liquiritigenin to obtain a better effect for uterine morphology, vaginal histopathology, and hot flushes. The other aim was to analyze the pharmacokinetic interaction that can affect the level of equol from EVU. Thirty-six female Sprague-Dawley rats were used in this study, 32 rats were ovariectomized (OVX) and 4 rats were Sham. Rats were divided into 9 groups: Sham group (CMC), negative group (CMC), positive group (raloxifene), EVU (100 mg/200g BW), EEB (18 mg/200g BW), The four various doses of combination EEB and EVU (D1-D4) were, EVU dosage was 100 mg/200 g BW and EEB were 36 mg, 18 mg, 9 mg, 4.5 mg/200 g BW respectively. Equol in rat serum was analyzed using HPLC/UV-V is in an isocratic condition. Observation of hot flushes was carried out every week, uterus weight wet and vaginal epithelium at the end of the treatment. The D3 and D4 combination decreased the average tail skin temperature 1.86±0.31°C and 1.83± 0.20°C respectively and the rectal temperature 0.58±0.49°C and 0.71±0.28°C (P<0.05). All groups except Sham did not increase the weight of the uterus. The D3 group increased vaginal epithelial thickness to 38.24 ± 6.47 μm (P<0.05). The combination did not significantly change equol pharmacokinetic parameters. The combination of Eleutherina bulbosa 70% ethanol extract (EEB) and Vigna unguiculata is better than EVU and EEB alone in reduced post-menopause syndrome in hypoestrogen rats without changing equol pharmacokinetic parameters.