Antioxidant effect of EGb 761 on hydrogen peroxide-induced lipoperoxidation of G-6-PD deficient erythrocytes.
ABSTRACT In order to reduce the haemolytic susceptibility of glucose-6-phosphate dehydrogenase (G-6-PD) deficient erythrocytes, Ginkgo biloba extract (EGb 761) and vitamin E (vit E) were used as antioxidant agents and their effects compared. The erythrocyte suspensions from control and G-6-PD deficient patients were subjected to hydrogen peroxide (H2O2) incubation for 1 h. The produced thiobarbituric acid reactive substance (TBARS) levels measured as nmol/g Hb were compared with those of the erythrocytes administered 250 microg/mL EGb 761 or vit E previously or concomitantly with H2O2. Preincubation with EGb 761 reduced the TBARS levels from 317.14 +/- 25.27 to 160.09 +/- 21.97 nmol/g Hb in controls and from 348.24 +/- 7.79 to 205.60 +/- 14.22 nmol/g Hb in deficient erythrocytes. Concomitant application of EGb 761 with H2O2 resulted in similar but less reduction. The antioxidative effects of vitamin E were comparable to those of EGb 761. Contrary to the results obtained from oxidant conditions, the antioxidant characteristics of EGb 761 and vitamin E were not observed when they were applied directly to the erythrocytes without oxidative stress. The findings demonstrate that irrespective of administration time, EGb 761 significantly reduced TBARS levels in the erythrocytes of control and G-6-PD deficient patients subjected to oxidative stress.
Article: ORAL SUPPLEMENTATION OF VITAMIN E REDUCES OSMOTIC FRAGILITY OF RBC IN HEMOLYTIC ANEMIC PATIENTS WITH G6PD DEFICIENCY[show abstract] [hide abstract]
ABSTRACT: Background: Vitamin E has role in maintaining the integrity of red cell membrane by preventing oxidation of polyunsaturated fatty acids, thus protects cells from oxidative stress-induced lysis in G6PD deficiency. Changes in osmotic fragility of RBC and some absolute values like MCV, MCH & MCHC may occur in haemolytic anaemic patients with G6PD deficiency. Objective: To observe the effects of vitamin E supplementation on these changes in order to evaluate the role of this anti-oxidant vitamin in reducing chronic haemolysis in G6PD deficient patients. Research design and method: A total number of 102 subjects with age ranged of 5 to 40 years of both sexes were included in the study. Among them 68 were G6PD enzyme deficient patients, of whom 34 were in supplemented group (experimental group) and 34 were in non-supplemented group (control group). The supplemented group received vitamin E supplementation for 60 consecutive days at a dose of 800 IU/day for adult and 400 IU/day for children ≤12 years (in a divided dose, i.e., 4 times daily). Age and sex matched 34 apparently healthy subjects with normal blood G6PD level were taken to observe the base line data (healthy control) and also for comparison. All the G6PD deficient patients were selected from Out Patient Department (OPD) of Haematology, Banglabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh from July 2005 to June 2006 and all healthy subjects were selected from personal contact. Blood G6PD level, osmotic fragility of RBC were measured by standard techniques and MCV, MCH, and MCHC were obtained by calculation. All the parameters were measured on day 1 of their first visit and also were on day 60 in deficient group. Data were compared among the deficient groups, also in supplemented group just before and after supplementation. Analysis of data was done by appropriate statistical method. Result: Mean starting and completing points of osmotic fragility of RBC were significantly higher but MCV. MCH, MCHC were significantly lower in patients suffering from haemolytic anaemia due to G6PD deficiency in comparison to those of the healthy control. After supplementation with vitamin E starting and completing points of osmotic fragility of RBC were significantly decreased whereas, MCV, MCH, MCHC were significantly increased towards those of healthy of healthy control in supplemented group of patients in comparison to those of their pre-supplemented (day-1) and non-supplemented groups both on day 1 and day 60. Conclusion: From this study it may be concluded that, disturbances of some of the haematological parameter like higher osmotic fragility of RBC and lower MCV, MCH, MCHC occur in G6PD deficient haemolytic anaemic patients, which returned towards normal after supplementation of vitamin E, which clearly indicates the role of this anti-oxidant vitamin in maintaining red cell membrane integrity and thereby decreases the rate of haemolysis in this group of patients. So, vitamin E can be supplemented along with other drugs for better management of the patients.Pak J Physiol. 01/2009; 5.