The effect of vitamin D on the expression levels of candidate genes associated with atherogenesis in rats with metabolic syndrome

In Metabolic Syndrome(MetS) where metabolic conditions like hypertension, central obesity,dyslipidemia,hyperglycemia coexist, and in atherosclerosis caused by high-fat and fructose nutrition, molecular pathogenesis is unclear.Aimed determine effect of Vitamin D(VitD) on aortic tissue morphology and endothelial damage during development of atherosclerosis in MetS rat model. Effect of VitD on aortic tissues of 10-12 weeks old Sprague Dawley male rats (n=32) fed normal(standard) diet and induced MetS on a high-fat-fructose(17%fat and 17%fructose feed+20%fructose water) diet,miR-21-5p and changes in miR-146a-5p expression levels by quantitative RT-PCR, histological changes in tissue morphology by Hematoxylin-Eosin,Masson triple stain and Von Kossa stains, target gene product of miR-21-5p TIMP3 and also α-SMA,p16,AMPK investigated immunohistochemically in aortic tissues.Half of control and MetS groups administered VitD(170 IU/week, oral) for 12 weeks. Skin thickness,waist circumference,weight,blood glucose monitored in all rats.Results evaluated statistically. End of experiment determined VitD had a significant effect on blood glucose and waist circumference values between groups compared to baseline(p≤0.05).Expression levels of miR-146a-5p found to increase with VitD between groups(p≤0.05).In histopathological examination, it was observed that smooth muscle cells in MetS group vacuolized in some areas and moved away from their healthy appearance,and vascular structure deteriorated, and this damage was largely corrected with VitD.Compared other groups, MetS group showed increase number of p16, α-SMA and AMPK immune positive cells, and decrease number of TIMP3 immune positive cells, although there was no statistical difference in expression levels of miR-146a-5p. Result, it was determined that metabolic syndrome caused by a high-fat-fructose diet, disrupted vascular structure, and vitD greatly corrected damage.