Insulin treatment prevents LDL from accelerated oxidation in patients with diabetes.
In a study population, we compared the level of malondialdehyde-modified LDL (MDA-LDL) with the concentrations of lipid parameters in serum and found a strong correlation between MDA-LDL and apolipoprotein B (apo B) concentrations. Their interrelations had a turning point at an apo B concentration of 1,150 mg/l. In diabetic patients, the ratio of MDA-LDL/apo B increased at apo B concentrations above 1,150 mg/l. This ratio represents the extent of modification of apo B by MDA. In the control subjects, this ratio remained stable. When we divided the patients into medication groups (statins and insulin), we found that the 1,150 mg/l threshold disappeared. At apo B concentrations above 1,150 mg/l, the ratio of MDA-LDL/apo B in the statin group was as high as that in the non-drug group. In the insulin group, the means of MDA-LDL/apo B in all ranges of apo B levels decreased to an extent statistically indistinguishable from those of the control group. In conclusion, insulin therapy represses LDL oxidation even at apo B concentrations > 1,150 mg/l and should be noted for its anti-oxidation properties.
Kondo
Akira
A
Department of Laboratory Medicine, Hamamatsu University School of Medicine, Shizuoka, Japan. kondoh@daiichichem.co.jp
Manabe
Mitsuhisa
M
Saito
Kazunori
K
Maekawa
Masato
M
Kanno
Takashi
T
D000328:Adult; D000368:Aged; D001055:Apolipoproteins B / Q000378:metabolism; D008076:Cholesterol, HDL / Q000378:metabolism; D008078:Cholesterol, LDL / Q000378:metabolism*; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy* / Q000378:metabolism*; D004586:Electrophoresis; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007004:Hypoglycemic Agents / Q000008:administration & dosage*; D000960:Hypolipidemic Agents / Q000008:administration & dosage; D007328:Insulin / Q000008:administration & dosage*; D008077:Lipoproteins, LDL / Q000378:metabolism; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D008875:Middle Aged; D014280:Triglycerides / Q000378:metabolism; D019014:fas Receptor / Q000378:metabolism
D001055:Apolipoproteins B; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D007004:Hypoglycemic Agents; D000960:Hypolipidemic Agents; D007328:Insulin; D008077:Lipoproteins, LDL; D014280:Triglycerides; D019014:fas Receptor; C099252:oxidized low density lipoprotein; D008315:Malondialdehyde