Relationship between apoptotic markers (Bax and Bcl-2) and biochemical markers in type 2 diabetes mellitus

Hasnan J, Yusoff MI, Damitri TD, Faridah AR, Adenan AS, Norbaini TH
Correspondence: Dr. Mohd Imran Yusof, drimran@kb.usm.my

ABSTRACT
Introduction Bax is essential for apoptosis in normal cells. However, overexpression of Bcl-2 enhances cell survival by suppressing apoptosis in cells subjected to apoptosis-inducing stimuli. The aim of this study was to examine the expression of apoptotic (Bax and Bcl-2) and biochemical markers in type 2 diabetics mellitus.
Methods A test group comprising 41 type 2 diabetes mellitus patients and a control group comprising 36 non-diabetic patients were enrolled in this study. Skin biopsy tissue samples were stained immunohistochemically for Bcl-2 and Bax expressions. Fasting plasma glucose (FPG), triglycerides, total cholesterol (TC), high-density lipoprotein cholesterol (HDLC) and glycosylated haemoglobin A1c (A1C) were analysed. Low-density lipoprotein cholesterol (LDLC) was calculated.
Results Bcl-2 expression was significantly higher (p-value is less than 0.001) in the control group. Bax expression was significantly higher (p-value is 0.018) in the diabetic group. Positive Bcl-2 expression was observed in 18 of 36 (50 percent) controls. Positive Bcl-2 expression was found in 5 of 41 (12.2 percent) diabetics. There was a significant difference (p-value is less than 0.001) between the two groups for mean FPG, HDLC and A1C. There was no significant difference for TC, LDLC and triglycerides between the two groups. Positive Bax expression was found in 11 of 35 (31.4 percent) controls. The odds of developing Bcl-2 among non-diabetics were 12.67 times compared to diabetics (p-value is less than 0.001).
Conclusion Prolonged hyperglycaemia induces apoptosis in the endothelial cells of diabetic ulcers, which aggravates microvasculopathy and delays tissue healing and regeneration.

Keywords: type 2 diabetes mellitus, apoptosis, biochemical markers
Singapore Med J 2010; 51(1): 50-55