Original article

Kuei-Lu-Er-Xian-Jiao extract enhances BMP-2 production in osteoblasts

¹ Physical Education Office, Tunghai University, Taichung 407, Taiwan
² Sports Recreation and Health Management Continuing Studies, Tunghai University, Taichung 407, Taiwan
³ School of Pharmacy, Tajen University, Pingtung 907, Taiwan
⁴ Graduate Institute of Chinese Medicine, China Medical University, Taichung 404, Taiwan
⁵ Department of Chinese Medicine, China Medical University Hospital, Taichung 404, Taiwan
⁶ Division of Endocrinology and Metabolism, Department of Internal Medicine, Taichung Veterans General Hospital, Taichung 407, Taiwan
⁷ Graduate Institute of Basic Medical Science, China Medical University, Taichung 404, Taiwan
⁸ Department of Pharmacology, School of Medicine, China Medical University, Taichung 404, Taiwan
⁹ Department of Biotechnology, College of Health Science, Asia University, Taichung 413, Taiwan

^* Corresponding author. Graduate Institute of Basic Medical Science, China Medical University, No. 91, Hsueh-Shih Road, Taichung 404, Taiwan. E-mail addresses: chtang@mail.cmu.edu.tw (C.-H. Tang); pochuen@tajen.edu.tw (P.-C. Shieh).

Received: 30 August 2016
Accepted: 14 September 2016

Abstract

Osteoporosis is a common skeletal disorder, resulting from an imbalance in bone resorption relative to formation. Bone morphogenetic protein (BMP) is a key regulator in bone formation and osteoblastic differentiation. Hence, compounds that promote BMP expression may be suitable candidates for osteoporosis treatment. This study examined the effects of the traditional Chinese medicinal agent, Kuei-Lu-Er-Xian-Jiao (KLEXJ), on BMP-2 production in osteoblasts. We found that KLEXJ extract promoted osteoblastic differentiation marker ALP activity and increased BMP-2 production; pretreatment with PI3K and Akt inhibitors, or small interfering RNA (siRNA), reduced these effects. KLEXJ also enhanced PI3K and Akt phosphorylation. Treatment of osteoblastic cells with NF-κB inhibitors (TPCK or PDTC) markedly inhibited KLEXJ-enhancement of ALP activity and BMP-2 production. KLEXJ also significantly promoted p65 phosphorylation, while treatment with PI3K and Akt inhibitors antagonized KLEXJ-enhanced p65 phosphorylation. Thus, KLEXJ enhances ALP activity and BMP-2 production of osteoblasts through the PI3K/Akt/ NF-κB signaling pathway and hence may be suitable in the treatment of osteoporosis.