Evaluation of Glutamate Dehydrogenase Activity and Insulin Secretion in Mice Exposed to Dexamethasone

Abstract

Background and Aims: Diabetes is one of the most important endocrine disrupters and is associated with various hormones, including those that
can lead to diabetes. Glucocorticoid use may lead to insulin resistance. Dexamethasone is one of these glucocorticoid compounds. Glutamate dehydrogenase plays a key role in the production of glutamate in the secretion of insulin. Based on these hormonal interactions, the aim of this study was to determine the activity of glutamate dehydrogenase and insulin secretion in dexamethasone-exposed mice.

Materials and Methods: Twenty eight mice were divided into 4 experimental groups. Group 1 received standard normal saline as a control. Group 2 received standard food and received 1 mg / kg dexamethasone per day. Group 3 received standard diet and dexamethasone 3 mg / kg / day and group 4 with standard diet 5 mg / kg dexamethasone per day. After 21 days, the animals were killed, the pancreas and glutamate dehydrogenase, insulin, and serum glucose levels were determined.

Results: Dexamethasone increased serum glucose levels significantly (P <0.05). Dexamethasone increased the glutamate dehydrogenase activity and insulin levels in dexamethasone treated mice (p<0.05)

Conclusions: These results suggestd that dexamethasone increases glucose which leads to elevating glutamate dehydrogenase activity, and then increasing insulin. However, insulin was not enough to normalize glucose levels and
led to hyperglycemia. Therefore, it is suggested to reduce dexamethasone administration.