REN and chronic kidney disease: Surprisingly, despite the state-of-the-art therapeutic and advanced pharmaceutical strategies, such as the uses of angiotensin converting enzyme inhibitor (ACEI), angiotensin II type I receptor blockade (ARB), and direct renin inhibitor (DRI), as well as good education, and renewed guideline for CKD precise management, progressive deterioration of renal function is frequently observed, subsequently leading to the adverse development of end-stage renal disease (ESRD) in CKD patients [15–20].