NGF and Alzheimer disease: In addition, NSCs produce a range of neurotrophic molecules, notably brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF), which support endogenous neurogenesis and synaptic remodeling, thereby helping to improve the impaired neural microenvironment observed in AD (L et al., 2021; Hsu et al., 2007; Salgado et al., 2015).