Effect of lipid peroxides and antioxidants on glycation of hemoglobin: an in vitro study on human erythrocytes.
BACKGROUND
Glycation and lipid peroxidation are two important processes known to play a key role in complications of many pathophysiological process. We sought to assess the possibility of an interaction between these processes in vitro and to examine the effect of lipoic acid and taurine on the glycation of hemoglobin and lipid peroxidation.


METHODS
Human erythrocytes in phosphate buffered saline (pH 7.4) were incubated with 5 or 50 mmol/l glucose. To study the effect of antioxidants on glycation of hemoglobin, erythrocytes were incubated with either lipoic acid or taurine and then exposed to glucose concentration of either 5 or 50 mmol/l. To clarify if lipid peroxides per se enhances the glycated hemoglobin level, an in vitro study was performed by incubating erythrocyte suspension containing either 5 or 50 mmol/l glucose with or without MDA. Lipid peroxides and glycated hemoglobin levels were determined in the glucose treated cells.


RESULTS
Glycated hemoglobin levels were higher in erythrocytes incubated with 50 mmol/l glucose concentrations than in erythrocytes incubated with 5 mmol/l glucose. The increase in glycated hemoglobin levels was blocked significantly when erythrocytes were pretreated with either lipoic acid or taurine. Both the antioxidants used in the present study markedly reduced the MDA levels. The level of glycated hemoglobin in erythrocyte incubated in the presence of MDA was increased significantly when compared to erythrocyte incubated with glucose alone.


CONCLUSIONS
Lipid peroxides per se may have a role to play in glycation of hemoglobin and antioxidants (lipoic acid and taurine) can partially inhibit the formation of glycated hemoglobin by lowering the levels of lipid peroxides.
Selvaraj
N
N
Department of Biochemistry, Jawaharlal Institute of Postgraduate Medical Education and Research, Pondicherry, 605 006, India.
Bobby
Zachariah
Z
Sathiyapriya
V
V
D000975:Antioxidants / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004912:Erythrocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D005947:Glucose / Q000494:pharmacology; D006442:Glycated Hemoglobin / Q000378:metabolism*; D006801:Humans; D008054:Lipid Peroxides / Q000097:blood*; D008315:Malondialdehyde / Q000378:metabolism / Q000494:pharmacology; D013654:Taurine / Q000494:pharmacology; D008063:Thioctic Acid / Q000494:pharmacology
D000975:Antioxidants; D005947:Glucose; D006442:Glycated Hemoglobin; D008054:Lipid Peroxides; D008315:Malondialdehyde; D013654:Taurine; D008063:Thioctic Acid