KL and metabolic syndrome: Given that a landmark study shows that inflammation and metabolism are the primary dysregulated pathways in CKD tubulointerstitium [57], in which metabolic abnormalities mainly include abnormal lipid metabolism, coupled with a parallel relationship between soluble Klotho levels in peripheral blood and renal Klotho expression levels [2], as well as dyslipidemia and elevated inflammatory markers in CKD [61, 62], we speculate that there is a close relationship between Klotho and blood lipids, inflammatory markers and kidney function in the CKD population.