CD44 and nephrolithiasis: Succinate downregulated the expression levels of osteogenesis related genes, including IL-1, IL-6, and OPN, which is very close related to kidney injury and CaOx deposition in vivo.50,51 The decreased CaOx crystal adhesion by down-regulating the expression levels of CD68 and CD44 can provide an novel pathway to inhibit CaOx deposition in kidneys.52 The results warrant further investigation of the protective effect of succinate on kidney stones and modulation.53