ACAN and Alzheimer disease: Most studies report that hyperosmolarity inhibits differentiation-related gene and protein expression (Tao et al., 2013; Potocar et al., 2016); however, some studies indicate that moderate hyperosmolarity (around 400 mOsm) may promote the differentiation of AD-MSCs and BMSCs towards a chondrogenic phenotype and upregulate markers such as collagen II and aggrecan (Caron et al., 2013; Ahmadyan et al., 2018).