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bioRxiv · 10.1101/2024.11.07.622429

Pancreatic changes in obese mice supplemented with vitamin D

da Rocha, G.·dos Santos, N. P.·Mendonca, J. C.·Fassis, N. O. B.·Calsa, B.·Milanski, M.·Amaral, M. E.
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Abstract

This study investigates the impact of vitamin D supplementation on insulin secretion and pancreatic islet morphometry in a high-fat diet-induced obese mouse model. Male C57BL/6 mice were randomly assigned to two groups: a control group receiving a standard diet (C) and an obese group receiving a high-fat diet (H). After 12 weeks, the obese group was subdivided, with one subset continuing on the high-fat diet (H) and the other receiving vitamin D supplementation (HD) at 500 IU/kg via oral gavage for four weeks. Glucose tolerance tests, insulin sensitivity assessments, insulin secretion assays, and histological and immunohistochemical analyses for glucagon and PCNA were conducted. Vitamin D supplementation led to a reduction in fasting blood glucose levels and a significant increase in insulin secretion at 20 mM glucose, as indicated by an improved HOMA%B index, suggesting enhanced {beta}-cell protection. Additionally, vitamin D treatment resulted in a {beta}-cell percentage comparable to the control group and a notable increase in -cell population relative to the untreated obese group. However, elevated circulating cholesterol levels were observed in both obese groups, with a significant rise in hepatic triglycerides in the vitamin D-treated group. These findings highlight the potential of vitamin D to improve pancreatic secretory function in obese mice.

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da Rocha, G., dos Santos, N. P., Mendonca, J. C., Fassis, N. O. B., Calsa, B., Milanski, M., Amaral, M. E.. 2024-11-08. Pancreatic changes in obese mice supplemented with vitamin D. https://doi.org/10.1101/2024.11.07.622429

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