Menhaden fish oil attenuates postpartum depression in rat model via inhibition of NLRP3-inflammasome driven inflammatory pathway

Background and aim: Postpartum depression (PPD) is a familiar problem which is associated with about 10-20% of women after child delivery. Fish oil (FO) has a therapeutic potentials to many diseases including mood disorders. However, there is paucity of data on the effects of FO supplementation on PPD rat model. Hence, this study aimed at investigating the potentials of FO in ameliorating depressive-like behaviors in PPD rat by evaluating the involvement of NLRP3-inflammasome. Experimental procedure: Thirty six virgin adult female rats (n=6) were randomly divided into six groups; Group 1-3 were normal control (NC), Sham (SHAM) and ovariectomized group (OVX) respectively whereas group 4-6 were PPD rats forced-fed once daily with distilled water (PPD), fish oil (PPD+FO; 9 g/kg) and Fluoxetine (PPD + FLX; 15 mg/kg) respectively from postpartum day 1 and continued for 10 consecutive days. Rats behaviors were evaluated on postpartum day 10 through open field test (OFT) and forced swimming test (FST), followed by biochemical analysis of NLRP3 inflammasome proteins pathway in their brain and determination of neutrophil to lymphocyte ratio (NLR). Results: PPD-induced rats exhibited high immobility and low swimming time in FST with increased inflammatory status; NLR, IL-1β and NFкB/NLRP3/caspase-1 activity in their hippocampus. However, administration of FO or fluoxetine reversed the aforementioned abnormalities. Conclusion: In conclusion, 10 days supplementation with FO ameliorated the depressive-like behaviors in PPD rats by targeting the NFкB/NLRP3/caspase-1/IL-1β activity. This has shed light on the potential of NLRP3 as a therapeutic target in treatment of PPD in rats.