Effects of Herbal Preparations Containing Isoflavones on Bone Metabolism in Postmenopausal Women
JIAN-PEI HUANG1,6, SUNG-YUAN WANG2, TZAY-SHING YANG3, HEN-HONG CHANG4, YUN-TING HSU2, CHIH-JUNG CHUNG1 AND YUH-CHENG YANG1,2,5,6*
1. Department of Obstetrics and Gynecology, 92, Sec. 2, Chung-Shan North Rd., Taipei City 104, Taiwan, R.O.C.
2. Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan, R.O.C.
3. Department of Obstetrics and Gynecology, Veterans General Hospital, Taipei, Taiwan, R.O.C.
4. Center for Traditional Chinese Medicine, Chang Gung Memorial Hospital & Graduate Institute of Traditional Chinese Medicine, Chang Gung University, Taoyuan, Taiwan, R.O.C.
5. College of Medicine, Taipei Medical University, Taipei, Taiwan, R.O.C.
6. Mackay Medicine, Nursing and Management College, Taipei, Taiwan, R.O.C.
(Received: January 24, 2005; Accepted: June 16, 2005)
ABSTRACT
The effects of the mixed herbal preparation “Tzuo-Kuai-Wuan” (TKW) on bone metabolism were compared with a single herb containing equivalent amounts of isoflavones, daidzein and genistein, and a combined estrogen-progesterone therapy (EPT). One hundred women completed the trial, 33 in group A, consuming a single herb, 30 in group B, consuming TKW, and 37 in group C, receiving EPT. In both herbal groups, the serum levels of daidzein significantly increased after treatment for 6 months (224% in group A and 234% in group B, both p < 0.01), though the serum levels of genistein did not change significantly. In group C , serum levels of either isoflavone changed only slightly. After 6 months of treatment, the bone formation marker (bone specific alkaline phosphatase [BSAP]) significantly increased in group B, but not in group A (25.4% vs. 15.9%, p < 0.01 and p 0.09, respectively). The elevation of BSAP was related to increased serum daidzein and genistein (ß = 0.498 and 0.248, p < 0.01 and p = 0.03, respectively). The bone resorption marker (urinary deoxypyridinolines/creatinine [Dpd/Cr]) was nearly the same at beginning of the study and after treatment in both herbal groups. In contrast, BSAP and Dpd/Cr significantly decreased after 3 and 6 months of treatment in group C (BSAP: 10.4% and 30.3%; Dpd/Cr: 21.7% and 43.8%, all p < 0.01 in paired t-tests). Thus, we conclude that TKW stimulates bone formation, in contrast to EPT which primarily inhibits resorption. This effect appears to be related to the amount of isoflavones. Further, the stronger effect in women consuming TKW than consuming a single herb that contains equivalent amounts of isoflavones suggests higher synergistic or additive effect of other components than isoflavones in TKW.
Key words: bone metabolism, daidzein, genistein, herb, isoflavones, osteoporosis