Curcumin mitigates lipopolysaccharide-induced anxiety/depression-like behaviors, blood–brain barrier dysfunction and brain edema by decreasing cerebral oxidative stress in male rats

Oxidative stress is a well-known risk factor for the development of anxiety and depression disorders. Curcumin, a natural compound, is an antioxidant with well-known neuroprotective functions. In the present study, we aimed to investigate the putative anxiolytic and antidepressant-like properties of curcumin, and its protective effects on blood-brain barrier (BBB) dysfunction and brain edema in lipopolysaccharide (LPS)-challenged rats, and the potential involvement of antioxidant properties of curcumin pretreatment. For this purpose, rats received 50 mg/kg of curcumin (gavage, 14 consecutive days) or saline prior to intraperitoneal administration of LPS. Subsequently, animals were submitted to the elevated plus maze (EPM), open field tests (OFT), and forced swimming test (FST), 24 h after LPS administration. Furthermore, BBB permeability and brain water contents were assessed in the brain tissue. Hence, GPX and SOD enzyme activity and MDA concentration were determined in the brain tissue using ELISA assay. Our results showed that curcumin significantly reduced LPS-induced anxiety-like behavior in EPM and OFT, increased exploratory activity, but without significant change in the locomotor activity. Pretreatment with curcumin attenuate LPS-induced BBB permeability and brain water content. Our biochemical assays showed that curcumin significantly increased the activity of SOD and GPX enzymes, as well as reduced MDA concentration in the brain tissue after LPS administration. Together, these results suggest that pretreatment with curcumin might mitigate LPS- induced anxiety and depressive-like behaviors, and attenuate brain edema and BBB permeability, possibly by its antioxidant properties.