The effect of carvacrol on experimental chronic stress in rats

Chronic Unpredictable Mild Stress (CUMS) is the closest stress model to the etiology of depression in humans. Carvacrol (CAR) is an active ingredient in the essential oil obtained from the thyme plant. It is frequently researched in humans and animals with its neuroprotective and many other beneficial properties. In this study, it was aimed to investigate the behavioral, anti-oxidant and anti-inflammatory effects of Carvacrol in rats with a CUMS model. A total of 49 Wistar Albino male rats (250-350 g) were randomly divided into 7 groups. The groups were as follows: Stress+DMSO (SDMSO); Stress+Carvacrol (40 mg/kg, SCAR); Stress+Fluoxetine (10 mg/kg, SFLU); Stress+Carvacrol+Fluoxetine (SCARFLU); Control+Carvacrol (CCAR), Control+DMSO (CDMSO); Control+Saline (CSALIN). The stress model was applied at moderate and unpredictable times for six weeks (42 days) according to a certain calendar. The treatments were applied once a day from the 20th day. The open field test (OFT) and elevated plus maze (EPM) were used for anxiety-like behavior, forced swim test (FST) for depression-like behavior, and the Barnes Maze test (BMT) for learning and memory. In addition, serum cortisol, thiol-disulfide homeostasis, total antioxidant level (TAS), total oxidant level (TOS), oxidative stress index (OSI) and IL1-beta levels were also evaluated. In rats with the CUMS model, serum cortisol, TOS, OSI levels increased and learning memory disorders were triggered. Conversely, administration of CAR and FLU prevented abnormal behavioral changes and changes in serum values. No significant difference difference was observed between the CAR treated rat groups and the FLU treated rat groups. Co-administration of CAR and FLU was less effective than their separate administration. The available data suggest that the therapeutic potential of CAR on chronic stress is comparable to that of FLU and that CAR is a potential candidate for future drug studies.