Restoration of Hypothalamic-Pituitary-Adrenal Axis Function in Rescue of Posttraumatic Stress Disorder in Curcumin-Treated Rats

摘要

Curcumin, an active ingredient of Curcuma longa, has been reported to enhance serotonin levels in various regions of the brain. The aim of this study was to evaluate the effect of curcumin in the treatment of posttraumatic stress disorder (PTSD) and on cortisol levels. The effect of curcumin on PTSD was studied using the predator scent stress (PSS) model at two dose levels (5 and 10 mg/kg), two phases of treatment (short term, 14 days, and long term, 28 days) and in two categories of rats (unexposed and exposed to PSS). Behavioral parameters such as performance on an elevated plus maze (EPM) and freezing response on re-exposure to the PSS were observed. Serum cortisol levels were estimated using chemiluminescence and were compared with those in paroxetine-treated groups. Long term treatment with both dose levels of curcumin effected a marked increase in the number of open arm entries, while short term treatment had a significant effect only at 10 mg/kg. Cortisol levels were also increased significantly on long term treatment with curcumin. This decrease in the anxiety index and freezing response indicates the therapeutic potential of curcumin for treating PTSD. Further, the increased cortisol levels reinforce the restoration of HPA-axis function, which normally becomes dysfunctional in PTSD.