Neuroprotective effects of increasing levels of HSP70 against neuroinflammation in Parkinson's disease model by inhibition of NF-κB and STAT3

Aims: The present study was aimed to investigate the neuroprotective effect of HSP70 against neuroinflammation in a rotenone-induced Parkinson's disease model. Materials and methods: In the present study, SH-SY5Y cells were treated with HSP70 (5-20 mg/L) for 72 h. Cell viability, reactive oxygen species (ROS) levels, mitochondrial membrane potential (MMP), levels of oxidative markers, mitochondrial fragmentation, apoptosis, and mRNA and protein expressions of signal transducer and activator of transcription (STAT)-3 and nuclear factor-kappa B (NF-kappa B) were assessed. Key findings: Cells treated with 5, 10, 15, and 20 mg/L of HSP70 exhibited increased, by 61.7%, 70.3%, 84.6%, and 96.7%, respectively, in cell viability. ROS and lipid peroxidation levels decreased following treatment with HSP70, and reductions in glutathione (GSH), catalase, glutathione peroxidase (Gpx), and superoxide dismutase (SOD) levels were reversed following treatment with HSP70. Additionally, MMP levels were reduced by 29.7, 46.4, 79.5, and 125.2 relative units following treatment with 5-20 mg/L of HSP70, respectively. HSP70 treatment also decreased levels of fragmented mitochondria and apoptosis, and mRNA and protein expressions of NFKB and STAT3 were reduced by > 25%. Significance: Taken together, these findings indicate that supplementation with HSP70s recovered cell viability and MMP and reduced levels of ROS, apoptosis, and mitochondrial fragmentation. Additionally, supplementation with HSP70 significantly reduced the expressions of STAT3 and NF-kappa B.