The Effects of Thyroid Hormones on Glucokinase Enzyme Activity in diabetic Rat Liver Tissues

Year 2019, Volume: 2 Issue: 3, 105 - 112, 09.08.2019

Duygu Şahin , Nilgün Altan Aylin Sepici-dinçel Atilla Engin

Abstract

Objective: We aimed to investigate the effcts of insulin and various doses of thyroid hormones with combine treatment on glucokinase (GK) enzyme activity, which is the one of the key enzyme in carbohydrate metabolism, diabetes and hypothyroidism. 

Material and methods: Rats were assigned to eight groups: Group 1: control, Group 2: diabetes (DM), Group 3: DM + insulin, Group 4: thyroidectomized control, Group 5: thyroidectomized + DM, Group 6: thyroidectomized + DM + insulin, Group 7: thyroidectomized + DM + insulin + thyroid hormone (TH) (2.5μg/kg), Group 8: thyroidectomized + DM + insulin + TH (5 μg/kg). Glucose concentration, HbA1c and thyroid hormone levels were measured in blood samples and GK enzyme activities were determined in liver tissue samples.

Results: Our results showed that the glucokinase enzyme activities were significantly decreased in diabetic rat liver tissues compared to control group. Moreover it was observed that the enzyme activities were slightly regulated by insulin. It is demonstrated that decreased GK enzyme activity in thyroidectomized diabetic rat liver was regulated by insulin and various doses of thyroid hormones.

Conclusion: As a result the possible contribution of thyroid hormones to insulin effct to normalize diabetic induced changes in liver tissue has been shown.

Keywords

Glucokinase, Thyroid hormone, Diabetes Mellitus, Rat liver

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