Objective: Chicoric acid (CA) is a natural product with promising antioxidant and anti-inflammatory properties; however, its protective effect on methotrexate (MTX)-induced acute kidney injury (AKI) hasn't been reported. We investigated the effect of CA on MTX-induced AKI in rats, pointing to the role of NF-κB/NLRP3 inflammasome and Nrf2/ARE/HO-1 signaling.
Materials and methods: Wistar rats received 25 mg/kg and 50 mg/kg CA for 15 days and a single injection of MTX at day 16. At day 19, the rats were killed, and samples were collected for analyses.
Results: MTX induced a significant increase in serum creatinine and urea, and kidney Kim-1, reactive oxygen species (ROS), malondialdehyde and nitric oxide levels. In addition, MTX-induced rats exhibited multiple histopathological alterations, diminished antioxidant defenses, and decreased expression of Nrf2, NQO-1 and HO-1. CA prevented histological alterations, ameliorated kidney function markers, attenuated ROS production and lipid peroxidation, and boosted antioxidant defenses. CA suppressed the expression of NF-κB p65, NLRP3, caspase-1 and IL-1β in the kidney of MTX-induced rats. Furthermore, CA inhibited MTX-induced apoptosis as evidenced by the decreased expression of BAX and caspase-3, and increased Bcl-2 gene expression.
Conclusions: CA prevented MTX-induced AKI through activation of Nrf2/ARE/HO-1 signaling, and attenuation of ROS-induced activation of NF-κB/NLRP3 inflammasome signaling.
Keywords: Chicoric acid; Methotrexate; NLRP3 inflammasome; Nrf2; ROS.