Thus, in order to explore the hypothesis that CNTs could affect the tissue balance between the neurotrophic mature NGF (mNGF) and its neurotoxic counterpart, the precursor proNGF,42 we delivered MWCNTs to both healthy and diabetic rats, the latter known to be affected by mild cognitive impairment associated with neurodegeneration and dysregulation of NGF production and activity, especially at the hippocampal level.27–29. This evidence concerns the gene NGF and Cognitive impairment.