High Vitamin D Status before Conception, but Not during Pregnancy, Is Inversely Associated with Maternal Gestational Diabetes Mellitus in Guinea Pigs. Issue 12 (23rd October 2014)

• Record Type: Journal Article
• Authors: Tabatabaei, Negar; Rodd, Celia J; Kremer, Richard; Weiler, Hope A
• Is Part Of: Journal of nutrition. Volume 144:Issue 12(2014)
• Page Start: 1994
• Page End: 2001
• Publication Date: 2014-10-23
• Subjects: Vitamin D -- dose-response -- pregnancy -- gestational diabetes -- guinea pig; Nutrition -- Periodicals; Diet -- Periodicals; 613.205
• DOI: 10.3945/jn.114.197814
• Languages: English
• ISSNs: 0022-3166

Abstract

Abstract: Background: Whether there is a dose-dependent effect of maternal dietary cholecalciferol during pregnancy on maternal glucose tolerance is unknown. In addition, circulating osteocalcin is increased by 1, 25-dihydroxyvitamin D [1, 25(OH)2 D] and may improve glucose homeostasis. Objective: This study was designed to test whether dietary cholecalciferol during pregnancy dose-dependently affects maternal glucose tolerance and maternal and neonatal glucose concentrations in relation to plasma osteocalcin and body composition. Methods: Female guinea pigs ( n = 45; 4 mo old) were randomly assigned to 5 doses of cholecalciferol (0, 0.25, 0.5, 1, or 2 IU/g diet) fed from mating to delivery. Plasma vitamin D metabolites, minerals, and osteocalcin, and blood glucose were measured before mating, at midgestation (day 42), and at day 2 postpartum in sows and in 2-d-old pups. At day 50 of pregnancy (early third trimester), a 3-h oral-glucose-tolerance test (OGTT) (2 g/kg) was conducted. Body composition was measured before mating and at day 2 postpartum in sows and in pups. Results: A positive dose-response to dietary cholecalciferol was observed for change in maternal plasma 25-hydroxyvitamin D [25(OH)D] through pregnancy ( P < 0.0001), with 1, 25(OH)2 D increasing by 198% in the 1-IU/g group by midgestation vs. a reduction of 43.6% in the 0-IU/g group ( P = 0.05). Twenty-four (54.5%) sows had gestational diabetes mellitus (GDM) on the basis of nonfed glucose and 39 (88.6%) had GDM on the basis of 2-h OGTT glucose concentrations. There were no group differences in maternal OGTT or changes in glucose, minerals, osteocalcin concentrations, and body composition. Pre-mating 25(OH)D was inversely related to 3-h area under the curve for blood glucose from the OGTT ( r = −0.31, P = 0.05). In guinea pig pups, although both 25(OH)D ( P < 0.0001) and 1, 25(OH)2 D ( P < 0.0001) followed a dose-response to maternal diet, glucose, osteocalcin, minerals, and body composition were not altered. Conclusions: Dietary vitamin D intake during pregnancy in guinea pigs does not affect the already high rate of GDM, whereas higher prepregnancy vitamin D status appears to be protective.