Author/Authors :
Nadimi, Hoda Department of Cellular and Molecular Nutrition - School of Nutritional Sciences and Dietetics - Tehran University of Medical Sciences , Djazayery, Abolghassem Department of Community Nutrition - School of Nutritional Sciences and Dietetic - Tehran University of Medical Sciences , Javanbakht, Mohammad Hassan Department of Cellular and Molecular Nutrition - School of Nutritional Sciences and Dietetics - Tehran University of Medical Sciences , Dehpour, Ahmadreza Experimental Medicine Research Center - Tehran University of Medical Sciences , Ghaedi, Ehsan Students’ Scientific Research Center (SSRC) - Tehran University of Medical Sciences (TUMS), Tehran , Derakhshanian, Hoda Department of Biochemistry - Nutrition and Genetics - Medical School - Alborz University of Medical Sciences, Karaj - Dietary supplements and probiotics Research Center - Alborz University of Medical Sciences, Karaj , Mohammadi, Hamed Student Research Committee - Department of Clinical Nutrition - School of Nutrition and Food Science - Isfahan University of Medical Sciences, Isfahan , Mousavi, Neda Department of Biochemistry and Nutrition - School of Medicine - Zanjan University of Medical Sciences, Zanjan , Djalali, Mahmoud Department of Cellular and Molecular Nutrition - School of Nutritional Sciences and Dietetics - Tehran University of Medical Sciences
Abstract :
Objective(s): Cyclic AMP (adenosine monophosphate) response element-binding protein (CREB) and
Brain-derived neurotrophic factor (BDNF) are reported to broadly involve in learning capacity and
memory. BDNF exerts its functions via tropomyosin receptor kinase B (TrkB). BDNF transcription
is regulated by stimulating CREB phosphorylation. The CREB-TrkB-BDNF pathway is reported to
be affected by diabetes, which may contribute to its cognitive deficits. This study was conducted to
investigate the effect of vitamin D supplementation on the hippocampal fraction of this pathway in an
animal model of type-1 diabetes mellitus (T1DM).
Materials and Methods: Thirty-six adult male Sprague-Dawley rats were randomly divided into 4
groups as follows: Group 1: normal healthy rats (n=8); group 2: normal healthy rats receiving sesame oil
supplementation as placebo (n=8); Group 3: diabetic rats receiving sesame oil (n=10); and Group 4: diabetic
rats treated with 4300 IU/kg/week vitamin D dissolved in sesame oil (n=10). Diabetes was induced by
intraperitoneal (IP) injection of streptozotocin. Blood and hippocampal samples were acquired at the end of
the experiment. RNA was extracted from the hippocampus, and real-time PCR (polymerase chain reaction)
was performed for BDNF and TrkB gene expression.
Results: Administration of vitamin D (4300 IU/kg/week) in a T1DM animal model increased CREB
phosphorylation in the hippocampus, but the serum and hippocampal BDNF levels and TrkB and
BDNF gene expression did not change significantly.
Conclusion: Vitamin D increased hippocampal CREB phosphorylation in a T1DM animal model. Our
findings showed that vitamin D might be protective against central nervous system complications in
diabetes. However, future studies are warranted.
Keywords :
Brain-derived neurotrophicfactor , CREB , Diabetes , TrkB , Vitamin D
