The Effects of Thyroid Hormones on Glucokinase Enzyme Activity in diabetic Rat Liver Tissues
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
References
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Details
Primary Language
English
Subjects
Clinical Sciences
Journal Section
Research Article
Publication Date
August 9, 2019
Submission Date
May 12, 2019
Acceptance Date
July 3, 2019
Published in Issue
Year 2019 Volume: 2 Number: 3