Age-related Changes in the Expression of Heat Shock Protein 70 and 90 on the Gastric Mucosa During Gastric Ulcer Healing

Heat shock proteins 70 and 90 (HSP-70 and HSP-90) are associated with gastroprotective and ulcer healing potentials. Reports in literatures have shown that age affects gastric ulcer healing, but the role of these heat shock proteins in relation to age has not been fully understood. This study, therefore, investigated changes in the expression of HSP-70 and HSP-90 in the gastric mucosa of 3, 6 and 18-month old rats during healing of Acetic acid-induced gastric ulcers. Male Wister rats (aged 3, 6 and 18 months) were divided into 3 groups according to their ages. Acetic acid ulcer model was used for this study. Ulcer area, oxidative stress, antioxidant markers, HSP-70 and HSP-90 concentration by ELISA and expression by immunohistochemistry was assessed. Results obtained indicate the highest percentage area healed on day 14 in 3 months old rats (100%), while percentage healing for 6 and 18 months old rats was 89.00% and 55.29%, respectively. Malondialdehyde (MDA) concentration was directly proportional to age, while antioxidant enzyme (Superoxide dismutase (SOD) and catalase (CAT)) activities were inversely proportional to age. The concentration and expression of HSP-70 were inversely proportional to age while HSP-90 had directly proportionality to age. The histological architecture also confirmed the faster rate of healing in 3-month old rats recorded in this study.This study indicates that HSP-70 and HSP-90 play different roles in age-related healing of gastric ulcers.