Quercetin mitigates doxorubicin-induced neurodegenerative changes in the cerebral cortex and hippocampus of rats; insights to DNA damage, inflammation, synaptic plasticity

Doxorubicin (Dox) is one of the most effective anti-neoplastic agents. Quercetin (QE) exhibits antioxidant and anti-inflammatory properties. To detect neuroprotective properties of quercetin in rats exposed to doxorubicin-induced brain injury. 48 rats were allocated equally into four groups: control group : (given normal saline), QE group : (given 80 mg/kg of QE orally daily for 2 weeks), Dox group : (received 2.5 mg/kg of Dox every other day for a total of seven intraperitoneal injections), and Dox+QE group : (received 2.5 mg/kg of Dox every other day for a total of seven intraperitoneal injections and 80 mg/kg of QE orally daily for 2 weeks). Subsequently, biochemical analyses were carried out along with histopathological (light and electron microscopic) and immunohistochemical examinations of the cerebral cortex and hippocampus. The Dox group revealed a decline in the activities of superoxide dismutase, catalase, and glutathione peroxidase, along with an increase in malondialdehyde and an increase in DNA damage. Furthermore, sections of the cerebral cortex and hippocampus revealed neurodegenerative changes, decreased synaptophysin, and increased Interleukin-1 beta expressions. Biochemical and histopathological results were markedly improved by QE administration. It can be concluded that QE induces protective effects against Dox-induced neurotoxicity.