Green tea ( Camellia sinensis ) aqueous extract alleviates postmenopausal osteoporosis in ovariectomized rats and prevents RANKL-induced osteoclastogenesis in vitro

• Published in: Food & nutrition research Vol. 62; pp. 1 - 11
• Main Authors: Wu, Xin, Xie, Chuan-Qi, Zhu, Qiang-Qiang, Wang, Ming-Yue, Sun, Bin, Huang, Yan-Ping, Shen, Chang, An, Meng-Fei, Zhao, Yun-Li, Wang, Xuan-Jun, Sheng, Jun
• Format: Journal Article
• Language: English
• Published: Sweden Swedish Nutrition Foundation, SNF 08.10.2018; Open Academia; Swedish Nutrition Foundation
• Subjects: Acid phosphatase; Acid phosphatase (tartrate-resistant); Acid resistance; Acids; Alkaline phosphatase; Animal models; Biocompatibility; Biomedical materials; Bone loss; Bone mass; Bones; c-Fos protein; Cancellous bone; Cancer; Cardiovascular disease; Cathepsin K; Change detection; Cytokines; Estrogens; Fractures; Gene expression; Green tea; green tea aqueous extract; Homeostasis; Hormone replacement therapy; Immunoglobulins; In vitro methods and tests; In vivo methods and tests; Interleukin 6; Ligands; Lymphocytes; Matrix metalloproteinase; Menopause; Metabolism; Metalloproteinase; NF-AT protein; Oral administration; Original; Osteocalcin; osteoclast; Osteoclastogenesis; Osteoporosis; Ovariectomy; Phosphatase; Polymerase chain reaction; Polyphenols; Post-menopause; Prevention; Proteins; Rats; receptor activator of the nuclear factor kappa B ligand; Receptor mechanisms; Rodents; Tea; TRANCE protein; Transcription factors; Womens health; Beijing China; United States > US; China; receptor activator of the nuclear factor kappa B ligand; osteoclast; osteoporosis; ovariectomy; green tea aqueous extract
• ISSN: 1654-661X; 1654-661X
• DOI: 10.29219/fnr.v62.1478

Green tea ( [L.] Kuntze) belongs to the plant family Theaceae and is mainly distributed in East Asia, the Indian subcontinent and Southeast Asia. This plant has been proven to be beneficial to human health, and green tea is the second most consumed beverage in the world after water. However, until now, the effect of green tea aqueous extract (GTE) upon postmenopausal osteoporosis has remained unclear. In this study, we investigated the therapeutic effects of GTE on estrogen deficiency-induced osteoporosis and explored the possible mechanisms and . Ovariectomized (OVX) female rats were orally administered with GTE at doses of 60, 120, and 370 mg kg for 13 consecutive weeks. The biochemical parameters, bone gla protein, alkaline phosphatase, acid phosphatase, estrogen, interleukin-1β, and interleukin-6 in blood samples were detected, and histological change in bones was analyzed by hematoxylin and eosin staining. Meanwhile, the mechanisms of GTE on osteoclast formation were explored in RAW 264.7 cells induced by receptor activation of the nuclear factor kappa B ligand (RANKL). The results showed that GTE could increase bone mass and inhibit trabecular bone loss in OVX rats. Furthermore, real-time quantitative reverse transcription polymerase chain reaction analysis from experiments also showed that GTE reduced the mRNA expression of osteoclast-associated genes such as (cath-K), , , (NFATc1) and . In addition, GTE caused a reduction in the protein levels of NFATc1, c-Fos, c-src and cath-K. Evidence from both animal models and experiments suggested that GTE might effectively ameliorate the symptoms of osteoporosis in OVX rats and inhibit RANKL-induced osteoclast-specific gene and protein expression.