Plasma Kisspeptin Levels in Type 2 Diabetic Males at The Korle-Bu Teaching Hospital

ABSTRACT 

People living with type 2 diabetes mellitus is on the increase and research has established that there is decreased secretion of testosterone in Type 2 Diabetic Mellitus males which may be linked to decreased levels of kisspeptin secretion that can cause the development of diabetic complications such as erectile dysfunction. Decreased kisspeptin levels have strongly been linked to decreased secretion of gonadotropins from the pituitary gland and this causes type 2 diabetic males to have decreased levels of testosterone resulting in secondary hypogonadism. Kisspeptins, therefore exerts a major influence in the downstream regulations of gonadotropins and testosterone production in men with type 2 diabetes mellitus. The work aimed to determine the concentrations of plasma kisspeptin levels in type 2 diabetic males in Ghana, to establish a relationship between low kisspeptin and testosterone concentrations in Ghanaian males above age of 30, and also to identify factor(s) that may be linked to low kisspeptin in these men. One hundred and twenty male subjects above the age of 30 (60 type 2 diabetics and 60 nondiabetic) were selected for this investigation. Diabetic subjects were contacted during outpatient clinic appointments at the National Diabetes Management and Research Centre (NDMRC), KorleBu Teaching Hospital. Non-diabetic matched control subjects were recruited by convenience sampling at the same catchment area. Kisspeptin, luteinizing hormone (LH), follicle stimulating hormone (FSH) and testosterone (TT) concentrations in subject’s sera were assessed using ELISA assays performed according to manufacturer’s instructions. Age, blood pressure, lipid profile, body mass index (BMI), and waist circumference of subjects were assessed. Significant lower levels of kisspeptin (ng/ml) was seen in diabetic males compared to the non-diabetic males (8.34±7.6 vs 16.26±12.72, p=0.001). Serum TT (ng/ml) was similarly significantly lower in the diabetic males compared with non-diabetic group (6.49±9.62 vs 11.38±2.56, p=0.001). Serum LH (mlU/ml) in v subjects (14.67±9.62 vs 10.82±2.37, p=0.003) and FSH (mlU/ml) in subjects (5.83±17.29 vs 10.39±2.65, p=0.017) were both significantly elevated in type 2 diabetic males than in the control group. The results revealed a significant difference in BMI and blood pressure of diabetic group compared to the non-diabetic controls (p0.005). Both FBG and HbA1c were raised in diabetic subjects compared to non-diabetic and the difference was significant (p=0.001 in both cases). Plasma kisspeptin levels in type 2 diabetic males showed significant inversely association with age (r=-0.590, p=0.0001), BMI (r=-0.389, p=0.002) and T. Chol/HDL (r=-0.321, p=0.012) and a significant association with TT (r=0.531, p=0.0001), LH (r=0.432, p=0.001), FSH (r=0.366, p=0.004) and HDL (r=0.362, p=0.005). Blood pressure, waist circumference, FBG, HbA1c, T. Chol, TG, LDL, and VLDL did not show statistical significance (p>0.005) with plasma kisspeptin levels in males having type 2 diabetes mellitus. This investigation showed that low testosterone (OR= 1.473, p=0.003) and increase in age (OR= 0.890, p=0.004) are independent risk factors for low kisspeptin levels in males with type 2 diabetes mellitus. It can be concluded that low testosterone is a major risk factor for the development of low kisspeptin in Ghanaian adult males living with type 2 diabetes mellitus.