{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,16]],"date-time":"2026-09-16T12:11:19Z","timestamp":1789560679608,"version":"build-2803163510"},"reference-count":64,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2018,2,22]],"date-time":"2018-02-22T00:00:00Z","timestamp":1519257600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["81528024"],"award-info":[{"award-number":["81528024"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"The Hong Kong Polytechnic University Central Allocation Fund","award":["15100015"],"award-info":[{"award-number":["15100015"]}]},{"name":"The Hong Kong Polytechnic University","award":["1BBAB"],"award-info":[{"award-number":["1BBAB"]}]},{"name":"Shenzhen Basic Research Program","award":["JCYJ20151030164008764"],"award-info":[{"award-number":["JCYJ20151030164008764"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Oleanolic acid (OA) is a triterpenoid with reported bone anti-resorption activities. The present study aimed to characterize its bone protective effects in vivo and to study its effects on vitamin D metabolism, both in vivo and in vitro. OA significantly increased bone mineral density, improved micro-architectural properties, reduced urinary Ca excretion, increased 1,25(OH)2D3 and renal CYP27B1 mRNA expression in mature C57BL\/6 ovariectomised (OVX) mice. OA also improved bone properties, Ca balance, and exerted modulatory effects on renal CYP27B1 and CYP24A1 expressions in aged normal female Sprague\u2013Dawley rats. In addition, OA significantly increased renal CYP27B1 mRNA and promoter activity, and suppressed CYP24A1 mRNA and protein expressions in human proximal tubule HKC-8 cells. OA exerted bone protective effects in mature OVX mice and aged female rats. This action on bone might be, at least in part, associated with its effects on Ca and vitamin D metabolism. The present findings suggest that OA is a potential drug candidate for the management of postmenopausal osteoporosis.<\/jats:p>","DOI":"10.3390\/nu10020247","type":"journal-article","created":{"date-parts":[[2018,2,22]],"date-time":"2018-02-22T07:05:41Z","timestamp":1519283141000},"page":"247","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":25,"title":["Oleanolic Acid Exerts Osteoprotective Effects and Modulates Vitamin D Metabolism"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7413-295X","authenticated-orcid":false,"given":"Sisi","family":"Cao","sequence":"first","affiliation":[{"name":"Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiao-Li","family":"Dong","sequence":"additional","affiliation":[{"name":"Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China"},{"name":"Shenzhen Key Laboratory of Food Biological Safety Control, The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen 518057, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ming-Xian","family":"Ho","sequence":"additional","affiliation":[{"name":"Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wen-Xuan","family":"Yu","sequence":"additional","affiliation":[{"name":"Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ka-Chun","family":"Wong","sequence":"additional","affiliation":[{"name":"Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xin-Sheng","family":"Yao","sequence":"additional","affiliation":[{"name":"Institute of Traditional Chinese Medicine &amp; Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0729-8618","authenticated-orcid":false,"given":"Man-Sau","family":"Wong","sequence":"additional","affiliation":[{"name":"Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China"},{"name":"Shenzhen Key Laboratory of Food Biological Safety Control, The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen 518057, China"},{"name":"State Key Laboratory of Chinese Medicine and Molecular Pharmacology (Incubation), The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen 518057, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2018,2,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1837","DOI":"10.1016\/j.clinthera.2015.06.006","article-title":"The Pathophysiology and Treatment of Osteoporosis","volume":"37","author":"Drake","year":"2015","journal-title":"Clin. 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