URINARY EXTRACELLULAR VESICLES CARRYING KLOTHO IMPROVE THE RECOVERY OF RENAL FUNCTION IN AN ACUTE TUBULAR INJURY MODEL

Abstract Acute kidney injury, defined by a rapid deterioration of the renal function, is a common complication in hospitalized patients. Among the recent therapeutic options, the use of extracellular vesicles (EVs) is considered a promising strategy. Here we propose a possible therapeutic use of renal-derived EVs isolated from normal urine (uEVs) in a murine model of acute injury generated by glycerol injection. uEVs accelerated renal recovery, stimulating tubular cell proliferation, reducing the expression of inflammatory and injury markers and restoring endogenous Klotho loss. When intravenously injected, labelled uEVs localized within injured kidneys and transferred their miRNA cargo. Moreover, uEVs contained the reno-protective Klotho molecule. Murine uEVs derived from Klotho null mice lost the reno-protective effect observed using murine EVs from wild type mice. This was regained when Klotho negative murine uEVs were reconstituted with recombinant Klotho. Similarly, ineffective fibroblast-derived EVs acquired reno-protection when engineered with human recombinant Klotho. Our results reveal a novel potential use of uEVs, as a new therapeutic strategy for acute kidney injury, highlighting the presence and role of the reno-protective factor Klotho.