The comparison of vitamin C and vitamin E on the protein oxidation of diabetic rats.
1 We measured the plasma glucose and the glycosylated haemoglobin at the time of sacrifice in streptozotocin-induced diabetic mellitus (DM) rats. 2 In diabetic rats, plasma glucose and glycosylated haemoglobin was increased as compared with normal rats, and vitamin E inhibited the increase of glycosylated haemoglobin level but vitamin C had no effect. 3 The peroxidized proteins and lipids from the diabetic organs such as liver or kidney were measured to assess the oxidative damage. The 2,4-dinitrophenyl-hydrazine (DNPH) incorporation method was used to measure the peroxidized protein. In diabetic rats, DNPH incorporation was increased as compared with normal rats and vitamin E also inhibited the increase of DNPH incorporation but vitamin C had no effect. It suggests that the protein oxidation occurred on the liver in diabetic rats and the oxidative stress is general in the diabetic condition. 4 We measured the systolic arterial pressure and mean arterial pressure in normal rats, nephrectomy (NEPH)-rats, diabetic rats (DM), and NEPH-diabetic rats (NEPH-DM). Blood pressure was significantly increased in DM and NEPH-DM as compared with normal rats. 5 In conclusion, plasma glucose, glycosylated haemoglobin, and the oxidation of proteins or lipid were increased in diabetic rats. Vitamin E decreased the plasma glucose, glycosylated haemoglobin and the oxidation of proteins and lipid, but vitamin C had no effects.
Je
H D
HD
Department of Pharmacology, College of Pharmacy, Chung Ang University, Seoul 156-756, Republic of Korea.
Shin
C Y
CY
Park
H S
HS
Huh
I H
IH
Sohn
U D
UD
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D001205:Ascorbic Acid / Q000494:pharmacology*; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism*; D015227:Lipid Peroxidation; D008099:Liver / Q000378:metabolism; D008297:Male; D009392:Nephrectomy; D010084:Oxidation-Reduction; D011506:Proteins / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013311:Streptozocin; D014810:Vitamin E / Q000494:pharmacology*
D000975:Antioxidants; D011506:Proteins; D014810:Vitamin E; D013311:Streptozocin; D001205:Ascorbic Acid