An UHPLC-MS/MS method for simultaneous determination of ten sex steroid hormones in ovariectomy-induced osteoporosis rat and its application in discovery of sex steroid hormones regulatory components of Xian-Ling-Gu-Bao capsule.

Sex steroid hormones could directly affect the bone metabolism by regulating cell physiological functions. In female, it inevitably causes the abnormal levels of sex steroid hormones at post-menopause in vivo. Ovariectomized rats and mice are classic animal models of osteoporosis to better understand the action mechanism of anti-osteoporosis drugs. However, it is not clear whether Xian-Ling-Gu-Bao capsule (XLGB), a kidney-tonifying traditional Chinese medicine prescription, treat osteoporosis via regulating multiple sex steroid hormones. In the present study, a reliable method involving ultra high-performance liquid chromatography coupled with triple quadrupole mass spectrometry (UHPLC/TQ-XS-MS) was developed for simultaneous quantitative analysis of ten sex steroid hormones (three estrogens, five androgens and two progestogens) in rat and mouse serum. The results of methodology were acceptable. The validated method was then successfully applied in the determination of the levels of sex steroid hormones in ovariectomy-induced osteoporosis rats, as well as drug (17β-estradiol and XLGB) intervened rats. As a result, XLGB could not only significantly increase the level of 17β-estradiol, but also improve the levels of progesterone, 17α-hydroxyprogesterone and androstenedione. Combined with molecular docking results and pharmacokinetic parameters, psoralen, isopsoralen and sweroside were considered as the key effective components of XLGB to activate adenylyl cyclase on promoting the biosynthesis of multiple sex steroid hormones. It is the first time to evaluate the regulatory effect of kidney-tonifying traditional Chinese medicine prescription on the levels of steroids in ovariectomy-induced osteoporosis rat, as well as the potential substance basis and mechanism of steroid hormone regulation.