Green Tea Intake Reduces High-Fat Diet-Induced Sensory Neuropathy in Mice by Upregulating the Antioxidant Defense System in the Spinal Cord

One of the most common complications of obesity is peripheral nerve damage, which progresses to sensory neuropathy. Green tea (GT) intake has been associated with weight loss and metabolic biomarkers modulation due to its antioxidant properties. The present work characterized the effects of GT in high-fat diet (HFD)-induced neuropathy and investigated the mechanisms involved. C57BL/6J male mice were fed an HFD or control diet, associated with GT or vehicle intake for 16 weeks. Weight, blood glucose, and nociceptive thresholds were assessed. Morphological and morphometric analyses of the sciatic nerves were performed. Activation of the cellular antioxidant system in the spinal cord was assessed by real-time PCR. GT intake reduced weight gain, hyperglycemia, and the development of sensory neuropathy. Furthermore, in HFD-fed mice that consumed GT, the morphology of the sciatic nerve was preserved. RT-qPCR analysis showed that HFD-fed mice ingesting GT had higher spinal levels of superoxide dismutase, catalase, glutathione peroxidase, and nuclear factor erythroid 2-related factor 2 (NRF2) mRNA compared to the HFD-fed mice ingesting vehicle, suggesting that the endogenous antioxidant system was more activated in response to GT consumption. In conclusion, the data suggest that GT intake reduces HFD-induced neuropathy, probably by upregulating antioxidant gene expression.