European Journal of Biomedical and Pharmaceutical Sciences

DOWN-REGULATION OF BRAIN DERIVED NEUROTROPHIC FACTOR AND OXIDATIVE STRESS MARKERS IN INDUCED ANXIETY/DEPRESSIVE STATE IN RAT’S BRAIN

*Olorunfemi O. J., Okoseimiema S. C., Ibeachu P. C.

ABSTRACT

The prevalence of brain diseases due to depression caused by stress is alarmingly high and requires global attention. This work aimed at investigating brain derived neurotrophic factor (BDNF) in depressive states of stress-evoked Male Wistar rats. Hundred and fifty Male rats of about three-month old (180-200 g) were used for this study. The rats were grouped into A (control- normal rats, rats without any drugs or shock), B (rats injected celebrex drugs and left to stay for one week, seven weeks and fourteen weeks (acute, subchronic and chronic levels), C ( rats given ear shock/foot shock and left to stay for one week, seven weeks and forteen weeks), D ( rats given retro-inversion/head-down maneuver shock and left to stay for one week, seven weeks and fourteen weeks), E (rats given tail immersion/tail clip shock and left to stay for one week, seven weeks and fourteen weeks) and F ( rats given mechanical shock and left to stay for one week, seven weeks and fourteen weeks). The celebrex drugs used were injected to the rats at 0.1 mg/kg bw. Brain neurotrophic factor levels and antioxidant status were determined using enzyme-linked immunosorbent assay (ELISA) kits. BDNF levels decreased significantly in rats in groups D, E and F at subchronic and chronic levels when compared with the control. Total antioxidant capacity (TAC) increased significantly in rats in groups D and F while catalase (CAT) activities, superoxide dismutase (SOD) and reduced glutathione (GSH) levels increased significantly in rats in groups B, C, D and F respectively. Levels of malondialdehyde (MDA) increased significantly in groups B and E. The levels of BDNF in depressive states of stress-evoked Male Wistar rats therefore decreased. There was an increase in time spent in the Elevated plus maze, Novel Object recognition and Barnes maze which revealed a decline in memory, cognition and depression. In the overall, depression becomes established in the brain whenever the concentration of BDNF decreased abysmally low but became insignificant in expression whenever there is concomitant increase in the level of BDNF implying that BDNF could be chief determinant of depression.

Keywords: BDNF, depression, stress, anxiety, Antioxidant capacity.