A summary of the related literature showed that the bioactive compounds (asiatic acid, asiaticoside and madecassic acid) isolated from Centella asiatica extract [Fig. 10(a–c)] had positive effects against neurological diseases, generally through the mitogen-activated protein kinase (MAPK) signalling pathway by increasing the brain-derived neurotrophic factor (BDNF) contents [160]. This evidence concerns the gene WNK2 and nervous system disorder.