Background

Doxorubicin (DOX)-induced neurotoxicity is widely reported in previous studies. Oxidative stress has been validated as a critical event involved in DOX-induced neurotoxicity. As a selective autophagy adaptor protein, p62 is reported to regulate Keap1-Nrf2-ARE antioxidant pathway in response to oxidative stress. Curcumin (CUR) relieves depressive-like state through the mitigation of oxidative stress and the activation of Nrf2-ARE signaling pathway. However, the exact mechanism of CUR in alleviating DOX-induced neurotoxicity is still unknown.

Materials and methods

The rats were randomly divided into three groups: control group, DOX group, and DOX + CUR group. At the end of 3 weeks, the behavior tests as sucrose preference test (SPT), forced swimming test (FST), and novelty-suppressed feeding test (NSFT) were performed to assess anxiety- and depression-like behaviors. The rats were sacrificed after behavior tests, and the brain tissues were collected for biochemical analysis.

Results

It was observed that the administration of CUR could effectively reverse DOX-induced depressive-like behaviors. The exposure of DOX activated autophagy and increased oxidative stress levels, and the administration of CUR could significantly inhibit DOX-induced autophagy and suppress oxidative stress. More importantly, we also found that Keap1-Nrf2-ARE signaling pathway was involved in DOX-induced neurotoxicity and oxidative stress regulated by autophagy.

Conclusion

Our study demonstrated that CUR could effectively reverse DOX-induced neurotoxicity through suppressing autophagy and mitigating oxidative stress and endoplasmic reticulum (ER) stress.