The present study was undertaken to find out the ability of black tea extract (BTE) as a suitable alternative of adjunct for calcium supplementation in treating an ovariectomized rat model of early osteoporosis. Female Wistar rats weighing 140–150？g were divided into four groups consisting of six animals in each group: (A) sham-operated control; (B) bilaterally ovariectomized; (C) bilaterally ovariectomized + BTE; (D) bilaterally ovariectomized + 17β-estradiol. Results suggest that BTE could promote intestinal absorption of calcium significantly ( for duodenum and ileum; and for jejunum). This was found associated with enhanced activities of two relevant intestinal mucosal enzymes alkaline phosphatase ( for duodenum, jejunum, and ileum) and Ca2+ activated ATPase ( for duodenum, jejunum, and ileum). Such BTE-mediated promotion of calcium absorption was coupled with increase in serum estrogen titer ( ) and recovery of all urinary, bone, and serum osteoporotic marker parameters, including bone histological features. Serum parathyroid hormone level, however, was not altered in these animals ( ). A comparative study with 17β-estradiol, a well-known adjunct for calcium supplementation, indicated that efficacy of BTE in maintaining skeletal health is close to that of 17β-estradiol. This study suggests that simultaneous use of BTE is promising as a prospective candidate for adjunctive therapies for calcium supplementation in the early stage of menopausal bone changes. 1. Introduction Menopause and increasing age are associated with a decrease in calcium absorption that can contribute to the pathogenesis of osteoporosis [1]. Calcium supplements appear to be effective in reducing bone loss in women, but there is a considerable uncertainty about the effectiveness of calcium supplementation in preventing bone loss at the early stage of the menopause [2–4]. Several adjunctive therapies with calcium supplementation were attempted earlier to prevent osteoporosis in early stage of menopause [5, 6]. Of these different adjunctive therapies, HRT, SERMs, and vitamin D were mostly advised [7, 8], but with controversial results [5, 9, 10]. In addition, HRT and SERMs are associated with well-known adverse health effects like breast cancer [11], thromboembolism [9, 12], stroke, and cardiovascular disease early in the course of therapy [13, 14]. Several phytoestrogens were attempted earlier to prevent osteoporotic damages in menopausal condition. Such studies also had controversial results [15–17]. However, black tea (Camellia sinensis) has been reported as a medicinal plant
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