Micro RNAs and neuron survival have become important, with micro RNA 34a (miR 34a), which inhibits Sirt 1, relevant to metabolic diseases and neurogenesis (Figure 3), possibly through interactions with hepatocyte nuclear factor (HNF4/HNF1) alpha (MODY gene), which may be relevant to the diagnosis of NAFLD and neurodegenerative diseases [2,94,95,96]. Here, HNF4A is linked to neurodegenerative disease.