FNDC5 and kidney failure: Liu et al. found significantly decreased levels of irisin in patients with T2DM and renal failure, especially in stage 5 of chronic kidney disease, without finding associations with other biomarkers of nephropathy, assigning their results to muscle wasting, insulin resistance, and alterations in energy metabolism related to kidney disease, in addition to the negative association produced by uremic toxins in the expression of FNDC5 [30].