title: Association of leptin, 25-hydroxyvitamin D, and parathyroid hormone in women.
abstract: Vitamin D deficiency and adipocytokines have been implicated in the etiology of aging-related diseases such as cancer, osteoporosis, and diseases of the cardiovascular system. The association between elevated parathyroid hormone (PTH) and low 25-hydroxyvitamin D (25-OH-VitD) in plasma is used to define vitamin D deficiency, yet their associated mechanistic pathways are unclear. Utilizing plasma samples from women in a previous intervention study, we measured plasma 25-OH-VitD, leptin, adiponectin, PTH, and lipid levels. We observed strong positive associations for leptin with PTH, gamma -tocopherol, and body mass index (BMI) and inverse associations with 25-OH-VitD and adiponectin. Although commonly accepted that vitamin D deficiency causes hyperparathyroidism, we observed this association primarily in individuals with elevated leptin levels, suggesting that leptin may be an important modifier of this effect consistent with 25-OH-VitD-mediated inhibition of leptin. Leptin was highly correlated with the BMI/25-OH-VitD ratio (r = 0.80; P < 0.0001), consistent with a model in which BMI (adiposity) and 25-OH-VitD are the primary determinants of circulating leptin and PTH levels. This model may explain the failure of some studies to observe elevated PTH in vitamin D deficient adolescents and provides important insight into epidemiological studies exploring the associations of these individual biomarkers with chronic disease risk and mortality.
authors.affiliation: Cancer Research Center of Hawaii, 1236 Lauhala Street, Honolulu, HI 96813, USA.
authors.forename: Micah
authors.initials: M
authors.lastname: Maetani
authors.forename: Gertraud
authors.initials: G
authors.lastname: Maskarinec
authors.forename: Adrian A
authors.initials: AA
authors.lastname: Franke
authors.forename: Robert V
authors.initials: RV
authors.lastname: Cooney
mesh_terms: D052242:Adiponectin / Q000097:blood; D000328:Adult; D015992:Body Mass Index; D002338:Carotenoids; D004032:Diet; D005260:Female; D005638:Fruit; D006801:Humans; D006961:Hyperparathyroidism / Q000097:blood; D020738:Leptin / Q000097:blood*; D008055:Lipids / Q000097:blood; D010281:Parathyroid Hormone / Q000097:blood*; D012044:Regression Analysis; D012307:Risk Factors; D014675:Vegetables; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood
chemical_list: D052242:Adiponectin; D020738:Leptin; D008055:Lipids; D010281:Parathyroid Hormone; D014807:Vitamin D; D002338:Carotenoids; C104450:25-hydroxyvitamin D