Tehran University of Medical Sciences Journal of Nutritional Sciences and Dietetics 4 1 2018 01 02 215 215 EN Seyed Bahman Panahande Department of Clinical Nutrition, School of Nutritional Sciences and Dietetics, International Campus, Tehran University of Medical Sciences(IC-TUMS), Tehran, Iran. Zhila Maghbooli Endocrinology and Metabolism Research Institute of Tehran University of Medical Sciences, Tehran, Iran. Arash Hossein-nezhad Department of Medicine, Section of Endocrinology, Nutrition, and Diabetes, Vitamin D, Skin and Bone Research Laboratory, Boston University Medical Campus, Boston, Massachusetts, USA. Saeed Hosseini Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Department of Clinical Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences (TUMS), Tehran, Iran. 2018 02 08 2018 05 18 Objective: Despite the high prevalence of osteopenia in post-menopausal women, its current treatments are controversial. The present study was designed to investigate the effect of pine bark extract on the bone turnover process and its possible mechanism through OPG/RANKL signaling in postmenopausal osteopenic women. Methods: This randomized double-blind clinical trial will be conducted on postmenopausal osteopenic women in Shariati Hospital of Tehran University of Medical Sciences, Tehran, Iran. A total of 44 postmenopausal women with osteopenia will be randomly assigned to two study groups ─ one (n = 22) receiving a PBE supplement (250 mg/d) and one (n = 22) a placebo. Demographic characteristics and the past medical history (recorded measurements of bone turn-over markers, namely, PINP, BAP, CTx and OPG/RANKL) will be recorded before and after the intervention. Ethics and dissemination: The research was performed after obtaining approval from the Ethics Committee of Tehran University of Medical Sciences (IR.TUMS.VCR.REC.1395.1408), in line with the Helsinki Declaration. Prior to the commencement of the study, a written informed consent form was signed and dated by participants and investigators. The results will be released at the right time. Trial registration number: Pre-results, IRCT2015071123153N1 Discussion: This study will investigate the effect of pine bark extract supplementation on bone turnover in postmenopausal osteopenic women. The results may help practitioners to choose the better palliative treatment for osteopenic women. https://jnsd.tums.ac.ir/index.php/jnsd/article/view/215 https://jnsd.tums.ac.ir/index.php/jnsd/article/download/215/203