3.2.3. Diabetic Neuropathy

Neurodegeneration is characterized by increased free radical production and oxidative stress [115]. It has been proved that tea had neuroprotective e ffects due to its anti-inflammatory and antioxidant properties [116]. An in vivo study found that green tea could prevent autonomic nervous dysfunction by blocking the change of arterial pressure variability [77]. Furthermore, green tea extract could restore the analgesic e ffect of morphine on diabetic neuropathic pain by inhibiting the production of NO [117]. Further, EGCG could reduce the formation of neural tube defects in embryo caused by maternal diabetes mellitus in mice through blocking the expression and activity of DNA methyltransferase, and inhibiting DNA hypermethylation, and restoring the expression of neural tube closure essential gene [118]. However, the protective e ffects of tea other than green tea on diabetic neuropathy have been much less investigated, and it could be interesting to investigate whether other types of tea can be also e ffective to protect against diabetic neuropathy.
