title: Hepatoprotective effect of 17β-estradiol as antioxidant modulators against stress damage.
abstract: BACKGROUND
  Liver is one of the most important organs affected by exercise. According to the literature a few study to date has investigated the effects of estrogen supplementation on exercise-induced oxidative stress in liver tissue of rats.
  
  
  OBJECTIVE
  We aimed to investigate the effects of estrogen supplementation on oxidative stress markers in liver tissue of exercised rats.
  
  
  METHODS
  Male rats (n = 35) were divided as estrogen supplemented (n = 18) and non-supplemented groups (n = 17); these groups were further divided as rest and eccentric exercised groups. Eccentric exercise groups were further divided as rats killed after 1 hour and 48 hours of eccentric exercise. Estrogen (10 mg/kg) was administered subcutaneously for 30 days. Eccentric exercise was applied as treadmill run (15° downhill, 20 m/min) consisting of periods of "5 min" run and 2 min rest repeated 18 times. The rat liver was examined biochemically and histologically. Activities of GST, GSH-Px, CAT, SOD and MDA concentration were also measured spectrophotometrically.
  
  
  RESULTS
  Some disruptions were detected in experimental groups compared with the control group. Additionally, exercise training caused an increase in SOD and decrease in GSH-Px activities in some experimental groups. SOD activities increased significantly in group 3 (Estrogen (-), eccentric exercise (+) killed (after 1 h), compared with group 5 (Estrogen (-), eccentric exercise (+) killed (after 48 h). On the other hand, GSH-Px activities were also significantly decreased in groups 3, 4 and 5 compared with the control group. Leukocyte infiltration in liver increased after 48 hours compared with after 1 hour and estrogen supplementation was not able to prevent this infiltration.
  
  
  CONCLUSIONS
  Estrogen seemed to be not very effective to prevent eccentric exercise-induced liver damage.
authors: Department of Physiology, Medical Faculty, Kafkas University, Kars, Turkey.
authors: Serpil
authors: S
authors: Can
authors: Department of Emergency Medicine, Medical Faculty, Kafkas University, Kars, Turkey.
authors: Gulsen
authors: G
authors: Cigsar
authors: Department of Medical Laboratory Techniques, Vocational School of Health Services, Ataturk University, Erzurum, Turkey.
authors: Fatma
authors: F
authors: Gur Ozabacigil
authors: Department of Histology and Embryology, Medical Faculty, Kafkas University, Kars, Turkey.
authors: Selina
authors: S
authors: Aksak Karamese
authors: Department of Histology and Embryology, Medical Faculty, Ataturk University, Erzurum, Turkey.
authors: Jale
authors: J
authors: Selli
authors: Department of Physiology, Medical Faculty, Ataturk University, Erzurum, Turkey.
authors: Gulsum
authors: G
authors: Bacak
authors: Department of Histology and Embryology, Veterinary Faculty, Ataturk University, Erzurum, Turkey.
authors: Semin
authors: S
authors: Gedikli
authors: Department of Medical Biology, Medical Faculty, Kafkas University, Kars, Turkey.
authors: Gonul Zisan
authors: GZ
authors: Sahin
authors: Department of Emergency Medicine, Medical Faculty, Kafkas University, Kars, Turkey.
authors: Serdar
authors: S
authors: Yigit
authors: Department of Histology and Embryology, Medical Faculty, Kafkas University, Kars, Turkey.
authors: Ismail
authors: I
authors: Can
authors: Department of Physiology, Medical Faculty, Ataturk University, Erzurum, Turkey.
authors: Mustafa
authors: M
authors: Gul
keywords: Antioxidants; Estrogens; Exercise; Liver