title: Melatonin is more effective than ascorbic acid and β-carotene in improvement of gastric mucosal damage induced by intensive stress.
abstract: BACKGROUND
  Oxidative stress has been considered to play a primary role in the pathogenesis of stress-induced gastric damage. The aim of this study was to investigate the effects of melatonin, ascorbic acid and β-carotene on stress-induced gastric mucosal damage.
  
  
  METHODS
  Fifty-six male Wistar albino rats were divided into control, stress, stress + standard diet, stress + saline, stress + melatonin, stress + ascorbic acid and stress + β-carotene groups. The rats from stress groups were exposed to starvation, immobilization and cold by immobilizing for 8 h at +4°C following 72-hour food restriction. Following stress application, melatonin, ascorbic acid and β-carotene were administered for 7 days. Specimens of gastric tissue were prepared for microscopic and biochemical examinations.
  
  
  RESULTS
  Mean histopathological damage scores and mean tissue malondialdehyde levels were significantly decreased but mean tissue glutathione levels and glutathione peroxidase and superoxide dismutase activities were increased in treatment groups vs. stress groups in general. Mean histopathological damage scores of the stress + Mel group was lower than those of stress + D, stress + S, stress + β-car (p < 0.05) and stress + Asc groups (p < 0.005). Additionally, mean tissue catalase activity of the stress + Mel group was higher than that of stress + S (p < 0.005), stress + D (p < 0.05) and stress + β-car groups (p < 0.05).
  
  
  CONCLUSIONS
  Melatonin is more effective than ascorbic acid and β-carotene in improvement of gastric damage induced by intensive stress. We suggest that as well as the direct antioxidant and free radical scavenging potency of melatonin, its indirect effect via the brain-gut axis might account for its greater beneficial action against stress-induced gastric damage.
authors.affiliation: Dogu Fertil Tup Bebek Merkezi, Malatya, Turkey.
authors.forename: Aysin
authors.initials: A
authors.lastname: Akinci
authors.affiliation: Department of Histology and Embryology, Medical Faculty, Bezmialem Vakif University, Istanbul, Turkey.
authors.forename: Mukaddes
authors.initials: M
authors.lastname: Esrefoglu
authors.affiliation: Department of Histology and Embryology, Medical Faculty, Inonu University, Malatya, Turkey.
authors.forename: Asli
authors.initials: A
authors.lastname: Cetin
authors.affiliation: Department of Chemistry, Faculty of Science and Art, Inonu University, Malatya, Turkey.
authors.forename: Burhan
authors.initials: B
authors.lastname: Ates
keywords: ascorbic acid; melatonin; stress; β-carotene