MP025RAPAMYCIN PROMOTES PODOCYTE AUTOPHAGY AND AGGRAVATES RENAL INJURY IN IUPUS NEPHRITIS

the last able to be phosphorylated by ILK.Therefore, we tested the hypothesis that ILK is required for NFATc-regulated AQP2 expression.METHODS: Adult conditional ILK knock-down (cKD-ILK) and NFATc3 isoform KO (NFATc3 KO) mice urine volumes and osmolality were compared with their corresponding littermates under physiological conditions.Their excised inner medullas were processed to determine the proteins levels.Collecting duct mIMCD3 cells, subjected to ILK depletion with siRNAs, were transfected with reporter plasmids for NFAT transcriptional activity.RESULTS: NFATc3 KO mice behaved similarly to cKD-ILK compared with their corresponding wildtypes as Nephrogenic Diabetes Insipidus (NDI) transgenic models, because the decreased AQP2 abundance and its capacity to concentrate urine.cKD-ILK renal inner medullas have increased levels of NFATc3, however its nuclear location is reduced.The activation of GSK3b was increased in these medullas, manifested as decreased serine-9 phosphorylation in the protein.We previously published (Cano-Peñalver et al.FASEB J. 2014) that ILK-depleted mIMCD3 have decreased AQP2 expression.New ILK-depleted cells show decreased phosphorylation of GSK3b and NFAT luciferase reporter activity, confirming its transcriptional reduced nuclear activity.This effect was reversed by the GSK3b inhibitor LiCl (0,1M).CONCLUSIONS: ILK inactivation may increase GSK3b-mediated nuclear export of NFATc3, leading to diminished AQP2 transcription.