Because of dose-dependent serious side effects such as back pain, injection site hyperalgesia, clinical trials of using NGF to treat various disorders such as diabetic neuropathies, chemotherapy-induced and human immunodeficiency virus-associated peripheral neuropathies were all discontinued.
In addition, salivary NGF was positively correlated with pro-inflammatory cytokines and further studies should be performed to evaluate whether it could be useful to detect diabetic neuropathy in T2D patients.
These findings suggest abnormally increased expression of NGF in diabetic neuropathy, which may represent a compensatory mechanism for impaired phenotype in NGF-responsive neurones.
The increased expression of p75NGFR in diabetic nerves is consistent with an axonopathic defect and further suggests involvement of NGF and other neurotrophins in the pathogenesis of human diabetic neuropathy.