Effect of surgical weight loss on free radical and antioxidant balance: a preliminary report.
BACKGROUND
This study observes the effect of surgical weight loss on free radical and antioxidant vitamin balance.


METHODS
22 consecutive morbidly obese patients undergoing vertical banded gastroplasty (VBG) were chosen for the study. Postoperative studies were done at 12 and 24 weeks. Plasma antioxidant and vitamin determinations were performed by HPLC method.


RESULTS
Subjects lost a significant amount of weight (P < 0.01). Compared to preoperative measurements, postoperative measurements of plasma beta-carotene were not statististically different both at 12 and 24 weeks (13.86 +/- 1.26 microg/dl, 12.35 +/- 1.2, P = 0.44; 14.33 +/- 2.03, P = 0.77; preoperatively, 12 and 24 weeks respectively). Alpha-tocopherol increased slightly at the 12th week; the difference was not significant (8.50 +/- 0.77; 9.56 +/- 0.82, P = 0.37; preoperatively and 12th week respectively). The levels of alpha-tocopherol rose at 24th week significantly (10.89 +/- 0.55, P = 0.028). The indicator of lipid peroxidation (malondialdehyde) decreased with weight loss (1.505 +/- 0.11 micromol/L preoperatively; 0.75 +/- 0.062 at 12th week, P = 0.01; 0.712 +/- 0.05 at 24th week, P < 0.01).


CONCLUSIONS
Our data show that free radical generation falls markedly in association with weight loss after VBG. Surgical weight loss leads to significant decrease in oxidant production and also leads to increase in some antioxidant vitamins. The demonstration of decreased free radical generation and correction of balance between free radicals and antioxidant vitamins has important implications for oxidative mechanisms underlying obesity-associated disorders.
Kisakol
Gurcan
G
Department of Internal Medicine, Section of Endocrinology, Meram Medical Faculty of Selcuk University, Meram/Konya, Turkey. gurcank@hotmail.com
Guney
Engin
E
Bayraktar
Firat
F
Yilmaz
Candeger
C
Kabalak
Taylan
T
Ozmen
Dilek
D
D000328:Adult; D000975:Antioxidants / Q000032:analysis*; D005260:Female; D005609:Free Radicals / Q000032:analysis*; D015391:Gastroplasty; D006801:Humans; D015227:Lipid Peroxidation; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D008875:Middle Aged; D009752:Nutritional Status; D011184:Postoperative Period; D015431:Weight Loss / Q000502:physiology*; D024502:alpha-Tocopherol / Q000097:blood; D019207:beta Carotene / Q000097:blood
D000975:Antioxidants; D005609:Free Radicals; D019207:beta Carotene; D008315:Malondialdehyde; D024502:alpha-Tocopherol