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Abstract
Well-known associations have been proved to exist between age-dependent androgen level decrease in males and risk of development of insulin resistance, metabolic syndrome, and hypogonadism. The authors present a hypothetic scheme describing the mechanism of development of these conditions. There are
grounds to affirm that an investigation of androgen receptor (АR) gene may be a useful additional method permitting to assess the risk of development of type 2 diabetes complications. One of such approaches is determination of polymorphic length CAG (cytosineadenine-guanine) trinucleotide repeats (CAGn) in the АR gene, this length being inversely correlated with the transcriptional activity of target genes of testosterone. The determination of (CAG)n length has been carried out parallel with an assessment of anthropometric, lipid, and hormonal status of 42 males with type 2 diabetes aged from 50 to 80 years. These
patients were treated with hypoglycemic tablets and were divided into two groups depending on their serum C-peptide levels (in the range 0.75-3.0 ng/ml and above 3.0 ng/ml). 15 males of corresponding age formed the control group. Besides, this group included also 20 males of corresponding age for which only (CAG)n length of the AR gene was determined. The (CAG)n was assessed using the polymerase chain reaction with DNA samples isolated from blood
leucocytes, the DNA fragments being analyzed on an automatic fluorescent analyzer. In elderly males with type 2 diabetes, in the presence of an increase
in C-peptide level, testosterone (T) levels - both total and free T - have been shown to decrease gradually compared with healthy subjects. The authors conclude that triglyceride levels in males with type 2 diabetes are increasing; this is especially expressed in males with C-peptide levels >3.0 ng/ml. The investigation of interactions between CAG-repeats number in the АR gene and androgen level shows the decrease in CAGn in this gene to be associated with a
reduction in serum T levels in males with type 2 diabetes. Positive correlations between CAG-repeat length and lipoprotein levels of both high and low density have been found both in healthy males and subjects with type 2 diabetes.
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