Effect of methylene blue on oxidative stress and antioxidant defence parameters of rat hepatic and renal tissues.

The objective of the present study was to investigate the effect of administration of 1 mM methylene blue (MB) in drinking water for 30 days on hepatic and renal antioxidant status in female adult Wistar strain rats (n=5). MB failed to induce significant change in any of the measured antioxidant defence parameters namely, superoxide dismutase (SOD), catalase (CAT) and reduced glutathione (GSH). However, a marginally significant (P<0.05) increase in the level of lipid peroxidation (LPx) was recorded in liver, while a reduction (P<0.05) in its level in the kidney was noticed. Serum alanine amino transferase (AlaAT) and creatinine levels significantly (P<0.001) decreased in MB treated rats without any change in blood urea nitrogen (BUN) level. Our findings suggest that the effect of MB as administered in the present study was tissue specific with regard to the level of LPx, however, in general, it does not impair liver and kidney functions as evidenced by serum parameters.

Photochemical effect of MB on the inactivation of E. coli in blood and biologic functions of blood cells / 第三军医大学学报

Objective To observe the photochemical effect of methylene blue (MB) on the inactivation of E. coli in blood and on biological functions of blood cells. Methods The blood was treated with 15 ?mol/L MB, 40 000 Lux halogen lamp irradiation and 0.35 mmol/l rutin for 10～40 min. The photochemical effect of MB on the inactivation of E.coli in blood was observed. The changes of biologic functions of blood cells were measured by means of RBC membrane binding to poly L lysine, reaction promoted by ATP enzyme and neutrophil phagocytosis tests. Results After treatment for 40 min, the E.coli count in blood decreased by 5 log units. The value of T/E of MB and irradiation of halogen lamp was higher than 1. No obvious changes of the morphology of blood cell were found. The negative electrical charges on membrane of RBC decreased by 11.23%～25.49%. After treatment of the blood for 20～30 min, the activity of Na + K +ATP enzyme of RBC membrane increased by 7.60%～20.07%. When the blood had been treated for 10～20 min, the positive rate of neutrophil phagocytosis enhanced by 9.00%. Conclusion MB photochemical treatment can effectively inactivate E. coli in blood. Under morphology specific condition of effectively inactivated blood bacteria, the shapes and functions of blood cells are not altered, but the RBC adhesion may increase by about 11.23%～25.49%.