Relationship between hyperglycemia, antioxidant capacity and some enzymatic and non-enzymatic antioxidants in African patients with type 2 diabetes.

BACKGROUND AND PURPOSE: Studies demonstrate that free radicals are involved in the pathogenesis of diabetic complications. The aim of this study was to determine the implication of total antioxidant capacity (TAC) and some enzymatic and non-enzymatic antioxidants as suitable biomarkers of diabetic complications risk factors. METHODS: A total of 90 patients (70 patients with or without diabetic complications +20 normal healthy) were examined by evaluating the level of lipid peroxidation, nitrogen monoxide (NO), fasting blood glucose, glycated haemoglobin (HbA1c), enzymatic and non-enzymatic antioxidants using standard spectrophotometric methods. RESULTS: The fasting blood glucose and HbA1c levels were respectively 2.05 and 2.32 times higher in the group of patients with diabetes and complications (DPWC) compared to those of healthy persons. A statistically higher level of malondialdehyde (MDA), NO and TAC was observed in a group of patients with diabetes and complications compared to those without complications (DPNC). A significant positive correlation was found between catalase (CAT) and fasting blood glucose while a significant and negative correlation was noted between reduced glutathione (GSH) and fasting blood glucose. Also was noted a significant relationship between HbA1c and other markers of oxidative stress. CONCLUSIONS: The results suggest that the plasma levels of CAT, TAC and reduced glutathione could give information on the risk of developing complications of diabetes, considering that the modification of these biomarkers levels were associated with oxidative stress.

Oxidative profile of sickle cell patients in a Cameroonian urban hospital.

BACKGROUND: Sickle cell disease (SCD) is a class of hemoglobinopathy resulting from a single mutation in the ß-globin chain inducing the substitution of valine for glutamic acid at the sixth amino acid position which leads to the production of abnormal haemoglobin (haemoglobin S [HbS]). Studies demonstrated the implication of oxidative stress in the development of the sickle cell disease. METHODS: The study aim was to determine the level of oxidative stress markers in a group of sickle cell homozygous patients (SS) in the Yaounde Central Hospital above 15 years of age. Hemolysates obtained from patients were used to investigate some oxidative stress markers including malondialdehyde (MDA), nitric oxide (NO), catalase (CAT), superoxide dismutase (SOD), peroxidase, total antioxidant capacity (TAC) and total protein concentration. RESULTS: Eighty four individuals, 42 males and 42 females participated (50 % each) with an age range of 15 to 55 years. The levels of markers were significantly higher in the healthy AA group than sickle (SS) (p < 0.05), with the exception of MDA which was significantly high in sickle cell (SS) patients than healthy (p = 0.037). With respect to the gender, both healthy and SS females showed a greater Total anti-oxidant capacity (65 µM) compared to the males (55 µM). CONCLUSION: The increase in the oxidative stress level especially MDA in sickle cell homozygous patients compared to healthy AA individuals confirms that oxidative stress is involved in the pathogenesis of the sickle cell disease.