DCXR, also known as HCR2, belongs to the short-chain dehydrogenases/reductases (SDR) family. It is highly expressed in kidney, liver and epididymis. In the epididymis, DCXR is mainly expressed in the proximal and distal sections of the corpus region. HCR2 is weakly or not expressed in brain, lung, heart, spleen and testis. DCXR catalyzes the NADPH-dependent reduction of several pentoses, tetroses, trioses, alpha-dicarbonyl compounds and L-xylulose. DCXR participates in the uronate cycle of glucose metabolism. It may play a role in the water absorption and cellular osmoregulation in the proximal renal tubules by producing xylitol, an osmolyte, thereby preventing osmolytic stress from occurring in the renal tubules.