{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,10]],"date-time":"2026-08-10T23:29:10Z","timestamp":1786404550386,"version":"build-2736575974"},"reference-count":31,"publisher":"Georg Thieme Verlag KG","issue":"08","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Horm Metab Res"],"published-print":{"date-parts":[[2026,8]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Severe vitamin D deficiency commonly results in secondary hyperparathyroidism and\n                    increased bone turnover. Despite the well-established inverse relationship\n                    between vitamin D and parathyroid hormone, the impact of vitamin D repletion on\n                    collagen matrix remodeling and adipose\u2013bone signaling remains unclear, and the\n                    combined response of prolidase and leptin has not been previously examined. This\n                    prospective observational study included 36 female patients with severe vitamin\n                    D deficiency and secondary hyperparathyroidism who received oral vitamin D\n                    supplementation (50,000 IU\/wk) for 8 weeks. Serum 25-hydroxyvitamin D,\n                    parathyroid hormone, alkaline phosphatase, prolidase activity, and leptin levels\n                    were assessed before and after treatment, and correlations among biochemical\n                    changes were analyzed. Vitamin D supplementation significantly increased serum\n                    25-hydroxyvitamin D levels and reduced parathyroid hormone and alkaline\n                    phosphatase concentrations (all p&lt;0.001). Serum prolidase activity\n                    increased significantly (p=0.027), whereas leptin levels showed a modest,\n                    non-significant decrease. Changes in prolidase activity were positively\n                    associated with baseline parathyroid hormone levels and inversely related to\n                    parathyroid hormone reduction. Post-treatment vitamin D levels demonstrated a\n                    modest positive correlation with leptin concentrations (r=0.347 and\n                        p=0.045), while no significant associations were observed between\n                    changes in vitamin D and prolidase or leptin levels. Vitamin D repletion in\n                    patients with severe vitamin D deficiency\u2013related secondary hyperparathyroidism\n                    was associated with distinct biochemical responses, with early collagen matrix\n                    remodeling reflected by increased prolidase activity and subtler changes in\n                    adipose\u2013bone signaling. These findings suggest temporally divergent pathways of\n                    skeletal recovery and support prolidase as a potential dynamic marker of early\n                    matrix adaptation.<\/jats:p>","DOI":"10.1055\/a-2897-4134","type":"journal-article","created":{"date-parts":[[2026,7,7]],"date-time":"2026-07-07T22:33:20Z","timestamp":1783463600000},"page":"311-317","source":"Crossref","is-referenced-by-count":0,"title":["Impact of Vitamin D Replacement on the Vitamin D\u2013Leptin\u2013Prolidase\n                    Axis in Secondary Hyperparathyroidism"],"prefix":"10.1055","volume":"58","clinical-trial-number":[{"clinical-trial-number":"nct05716750","registry":"10.18810\/clinical-trials-gov"}],"author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9462-9990","authenticated-orcid":false,"given":"Hatice K.","family":"Asik","sequence":"additional","affiliation":[{"name":"University of Health Sciences, Turkey","place":["Istanbul"],"department":["Department of Physical Medicine and Rehabilitation"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tugba","family":"\u015eahbaz","sequence":"additional","affiliation":[{"name":"Beykent University, Turkey","place":["Istanbul"],"department":["Department of Physical Medicine and Rehabilitation"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yildiz","family":"Atamer","sequence":"additional","affiliation":[{"name":"Beykent University, Turkey","place":["Istanbul"],"department":["Department of Medical Biochemistry"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Serdar","family":"Sara\u00e7","sequence":"additional","affiliation":[{"name":"Private Erenk\u00f6y Physical Therapy Center, Turkey","place":["Istanbul"],"department":["Department of Physical Medicine and Rehabilitation"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aytac","family":"Atamer","sequence":"additional","affiliation":[{"name":"Uskudar University, Istanbul, Turkey","place":["\u00dcsk\u00fcdar"],"department":["Department of Internal Medicine"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"194","published-online":{"date-parts":[[2026,7,7]]},"reference":[{"issue":"03","key":"ref1","doi-asserted-by":"crossref","first-page":"266","DOI":"10.1056\/NEJMra070553","article-title":"Vitamin D deficiency","volume":"357","author":"M F Holick","year":"2007","journal-title":"N Engl J Med"},{"issue":"04","key":"ref2","doi-asserted-by":"crossref","first-page":"477","DOI":"10.1210\/edrv.22.4.0437","article-title":"Vitamin D deficiency and secondary hyperparathyroidism in the elderly:\n                    consequences for bone loss and fractures and therapeutic implications","volume":"22","author":"P Lips","year":"2001","journal-title":"Endocr Rev"},{"issue":"01","key":"ref3","doi-asserted-by":"crossref","first-page":"132","DOI":"10.1186\/s40795-023-00786-x","article-title":"Evaluating the effect of vitamin D supplementation on serum levels of 25-hydroxy\n                    vitamin D, 1,25-dihydroxy vitamin D, parathyroid hormone and\n                    renin-angiotensin-aldosterone system: A systematic review and meta-analysis of\n                    clinical trials","volume":"9","author":"A Khodadadiyan","year":"2023","journal-title":"BMC Nutr"},{"issue":"01","key":"ref4","doi-asserted-by":"crossref","first-page":"83","DOI":"10.1007\/s00424-018-2231-z","article-title":"Physiological regulation of phosphate by vitamin D, parathyroid hormone (PTH)\n                    and phosphate (Pi)","volume":"471","author":"G Jacquillet","year":"2019","journal-title":"Pflugers Arch"},{"issue":"04","key":"ref5","doi-asserted-by":"crossref","first-page":"1109","DOI":"10.1210\/er.2018-00126","article-title":"Skeletal and extraskeletal actions of vitamin D: Current evidence and\n                    outstanding questions","volume":"40","author":"R Bouillon","year":"2019","journal-title":"Endocr Rev"},{"issue":"07","key":"ref6","first-page":"1","article-title":"Vitamin D in the endocrine circuit: Focus on interactions between vitamin D","volume":"16","author":"S Rosini","year":"2025","journal-title":"PTH and leptin. 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Dardeno","year":"2010","journal-title":"Front Neuroendocrinol"},{"issue":"19","key":"ref14","doi-asserted-by":"crossref","first-page":"e15832","DOI":"10.14814\/phy2.15832","article-title":"Impact of leptin deficiency on male tibia and vertebral body 3D bone\n                    architecture independent of changes in body weight","volume":"11","author":"A Williamson","year":"2023","journal-title":"Physiol Rep"},{"issue":"01","key":"ref15","first-page":"93","article-title":"Osteoporosis and leptin: A systematic review","volume":"53","author":"S M Mohammadi","year":"2024","journal-title":"Iran J Public Health"},{"key":"ref16","doi-asserted-by":"crossref","first-page":"1044039","DOI":"10.3389\/fendo.2023.1044039","article-title":"Effect of adipokine and ghrelin levels on BMD and fracture risk: An\n                    updated systematic review and meta-analysis","volume":"14","author":"S Lee","year":"2023","journal-title":"Front Endocrinol\n                        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Pogoda","year":"2006","journal-title":"J Bone Miner Res"},{"key":"ref23","doi-asserted-by":"crossref","first-page":"156053","DOI":"10.1016\/j.metabol.2024.156053","article-title":"Evidence from clinical studies of leptin: Current and future clinical\n                    applications in humans","volume":"161","author":"N Perakakis","year":"2024","journal-title":"Metabolism"},{"issue":"05","key":"ref24","doi-asserted-by":"crossref","first-page":"847","DOI":"10.1016\/j.bone.2003.07.008","article-title":"Serum leptin as a determinant of bone resorption in healthy postmenopausal\n                    women","volume":"33","author":"C Roux","year":"2003","journal-title":"Bone"},{"issue":"02","key":"ref25","doi-asserted-by":"crossref","first-page":"265","DOI":"10.1530\/JOE-12-0344","article-title":"1,25-Dihydroxyvitamin D3 upregulates leptin expression in mouse adipose\n                    tissue","volume":"216","author":"J Kong","year":"2013","journal-title":"J 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Biochem"}],"container-title":["Hormone and Metabolic Research"],"original-title":[],"language":"en","link":[{"URL":"http:\/\/www.thieme-connect.de\/products\/ejournals\/pdf\/10.1055\/a-2897-4134.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,10]],"date-time":"2026-08-10T22:59:56Z","timestamp":1786402796000},"score":1,"resource":{"primary":{"URL":"http:\/\/www.thieme-connect.de\/DOI\/DOI?10.1055\/a-2897-4134"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,7,7]]},"references-count":31,"journal-issue":{"issue":"08","published-online":{"date-parts":[[2026,8,10]]},"published-print":{"date-parts":[[2026,8]]}},"URL":"https:\/\/doi.org\/10.1055\/a-2897-4134","archive":["Portico","CLOCKSS"],"relation":{},"ISSN":["0018-5043","1439-4286"],"issn-type":[{"value":"0018-5043","type":"print"},{"value":"1439-4286","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,7,7]]}}}