Effects of hyperthyroidism on glucose, glutamine and ketone-body metabolism in the gut of the rat

Diabetic ketoacidosis as the initial presentation of hyperthyroidism

Abdominal pain is a common chief complaint that encompasses a broad differential diagnosis at emergency department (ED), ranging from general discomfort to life-threatening disease. Abdominal pain induced by a metabolic disorder should also be considered. Diabetic ketoacidosis (DKA) is a common complication of new-onset type 1 diabetes mellitus in young patients. Although DKA that presented to the ED with complaint of abdominal pain is not uncommon, it is precipitated by hyperthyroidism, which is rare and more complicated. Herein, we present a case of a 20-year-old women who came to our ED with the chief complaint of abdominal pain, which was actually the result of DKA caused by hyperthyroidism without underlying disease.

The effect of thyroid hormones on blood insulin level and metabolic parameters in diabetic rats

The effect of exogenous thyroid hormones on blood insulin and metabolic parameters in diabetic rats was investigated. Three groups of rats were treated with streptozotocin (STZ; 50 mg/kg b.w., intravenously) and one group receiving only saline served as control. Beginning with the third day after STZ treatment, until the last day before decapitation, i.e. for 11 days, two groups of diabetic rats were treated with T3 (50 microg/kg b.w., i.p.) or T4 (250 microg/kg b.w., i.p.). After two weeks, STZ injected rats had lower body weight, hyperglycemia with a simultaneous drop in blood insulin and decrease of T3 and T4 concentrations in comparison to control animals. Liver glycogen content was also reduced, whereas serum lactate, free fatty acids, triglycerides and cholesterol were elevated. Exogenous thyroid hormones given to diabetic rats substantially attenuated hyperglycemia without any significant changes in blood insulin concentration. An additional reduction of body weight gain and depletion in liver glycogen stores were also observed. Thyroid hormones augmented serum lactate and cholesterol and had no beneficial effect on elevated free fatty acids and triglycerides. It can be concluded that in spite of partial restriction of hyperglycemia, thyroid hormones evoked several unfavourable changes strongly limiting their potential use in diabetes.

Mitigation of thyroxine-induced hyperglycaemia by two plant extracts

Extracts of Trigonella foenum-graecum (TFG) seed and Allium sativum (AS) bulb were evaluated for their efficacy to ameliorate l-thyroxine (l-T4) induced hyperglycaemia in rats. Simultaneously, the serum cholesterol concentration, a supporting parameter for thyroid function, was also estimated. Thyroxine treatment in rats (300 microg/kg b. wt./day) increased the levels of both the thyroid hormones, namely thyroxine (T4) and tri-iodothyronine (T3) with a concomitant elevation in serum glucose concentration and a reduction in serum cholesterol level. Administration of TFG (220 mg/kg/day) and AS (500 mg/kg/day) extracts in hyperthyroid animals decreased the serum glucose concentration as well as the serum thyroid hormones. For comparison, propyl thiouracil (PTU), an antithyroid compound, was used as the standard at a daily dose of 10 mg/kg. The reductions in serum glucose and thyroid hormone concentrations in the plant extract treated groups were comparable to that in PTU treated animals. Our findings indicate that TFG seed and AS bulb extracts may prove to be effective in the treatment of thyroxine-induced hyperglycaemia.