Early-life stress altered pancreatic Krebs cycle-related enzyme activities in response to young adulthood physical and psychological stress in male rat offspring

Objectives: Early-life stress (ELS) increases the risk of metabolic disorders in later life. The present study investigated the ELS effect on pancreatic pyruvate dehydrogenase (PDH) protein level, alpha-ketoglutarate dehydrogenase (alpha-KGDH), and aconitase activities as metabolic enzymes in response to young adulthood stress in male rat offspring. Methods: Male Wistar rats were divided into six groups: Control, early life stress (Early STR), young adult foot-shock stress (Y. adult F-SH STR), early + young adult foot-shock stress (Early + Y. adult F-SH STR), young adult psychological stress (Y. adult Psy STR) and early + young adult psychological stress (Early + Y. adult Psy STR). Stress was induced by a communication box at 2 weeks of age and young adulthood for five consecutive days. The blood samples were collected in young adult rats, then pancreases were removed to measure its PDH protein level and aconitase and alpha-KGDH activities. Results: In ELS animals, applying foot-shock stress in young adulthood increased PDH protein level, decreased alpha-KGDH and aconitase activities, and increased plasma glucose, insulin, and corticosterone concentrations. However, exposure to young adulthood psychological stress only decreased alpha-KGDH and aconitase activities. Conclusions: It seems that ELS altered metabolic response to young adulthood stress through changes of Krebs cycle-related enzymes activities, though the type of adulthood stress was determinant.