Plasma 25-Hydroxyvitamin D Is Related to Protein Signaling Involved in Glucose Homeostasis in a Tissue-Specific Manner
AbstractVitamin D has been suggested to play a role in glucose metabolism. However, previous findings are contradictory and mechanistic pathways remain unclear. We examined the relationship between plasma 25-hydroxyvitamin D (25(OH)D), insulin sensitivity, and insulin signaling in skeletal muscle and adipose tissue. Seventeen healthy adults (Body mass index: 26 ± 4; Age: 30 ± 12 years) underwent a hyperinsulinemic-euglycemic clamp, and resting skeletal muscle and adipose tissue biopsies. In this cohort, the plasma 25(OH)D concentration was not associated with insulin sensitivity (r = 0.19, p = 0.56). However, higher plasma 25(OH)D concentrations correlated with lower phosphorylation of glycogen synthase kinase-3 (GSK-3) αSer21 and βSer9 in skeletal muscle (r = −0.66, p = 0.015 and r = −0.53, p = 0.06, respectively) and higher GSK-3 αSer21 and βSer9 phosphorylation in adipose tissue (r = 0.82, p < 0.01 and r = 0.62, p = 0.042, respectively). Furthermore, higher plasma 25(OH)D concentrations were associated with greater phosphorylation of both protein kinase-B (AktSer473) (r = 0.78, p < 0.001) and insulin receptor substrate-1 (IRS-1Ser312) (r = 0.71, p = 0.01) in adipose tissue. No associations were found between plasma 25(OH)D concentration and IRS-1Tyr612 phosphorylation in skeletal muscle and adipose tissue. The divergent findings between muscle and adipose tissue with regard to the association between 25(OH)D and insulin signaling proteins may suggest a tissue-specific interaction with varying effects on glucose homeostasis. Further research is required to elucidate the physiological relevance of 25(OH)D in each tissue. View Full-Text
Scifeed alert for new publicationsNever miss any articles matching your research from any publisher
- Get alerts for new papers matching your research
- Find out the new papers from selected authors
- Updated daily for 49'000+ journals and 6000+ publishers
- Define your Scifeed now
Parker, L.; Levinger, I.; Mousa, A.; Howlett, K.; de Courten, B. Plasma 25-Hydroxyvitamin D Is Related to Protein Signaling Involved in Glucose Homeostasis in a Tissue-Specific Manner. Nutrients 2016, 8, 631.
Parker L, Levinger I, Mousa A, Howlett K, de Courten B. Plasma 25-Hydroxyvitamin D Is Related to Protein Signaling Involved in Glucose Homeostasis in a Tissue-Specific Manner. Nutrients. 2016; 8(10):631.Chicago/Turabian Style
Parker, Lewan; Levinger, Itamar; Mousa, Aya; Howlett, Kirsten; de Courten, Barbora. 2016. "Plasma 25-Hydroxyvitamin D Is Related to Protein Signaling Involved in Glucose Homeostasis in a Tissue-Specific Manner." Nutrients 8, no. 10: 631.
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.