Vasopressin Regulates Extracellular Vesicle Uptake by Kidney Collecting Duct Cells

Abstract

Extracellular vesicles (ECVs) facilitate intercellular communication along the nephron, with the potential to change the function of the recipient cell. However, it is not known whether this is a regulated process analogous to other signaling systems. We investigated the potential hormonal regulation of ECV transfer and report that desmopressin, a vasopressin analogue, stimulated the uptake of fluorescently loaded ECVs into a kidney collecting duct cell line (mCCD) and into primary cells. Exposure of mCCD cells to ECVs isolated from cells overexpressing microRNA-503 led to downregulated expression of microRNA-503 target genes, but only in the presence of desmopressin. Mechanistically, ECV entry into mCCD cells required cAMP production, was reduced by inhibiting dynamin, and was selective for ECVs from kidney tubular cells. In vivo, we measured the urinary excretion and tissue uptake of fluorescently loaded ECVs delivered systemically to mice before and after administration of the vasopressin V2 receptor antagonist tolvaptan. In control-treated mice, we recovered 2.5% of administered ECVs in the urine; tolvaptan increased recovery five-fold and reduced ECV deposition in kidney tissue. Furthermore, in a patient with central diabetes insipidus, desmopressin reduced the excretion of ECVs derived from glomerular and proximal tubular cells. These data are consistent with vasopressin-regulated uptake of ECVs in vivo We conclude that ECV uptake is a specific and regulated process. Physiologically, ECVs are a new mechanism of intercellular communication; therapeutically, ECVs may be a vehicle by which RNA therapy could be targeted to specific cells for the treatment of kidney disease.

The effect of renal dysfunction and haemodialysis on circulating liver specific miR‐122

“…( Figure 3A). Haemodialysis induced a statistically significant, but clinically insignificant, increase in ALT from 12 (9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19) to 13 (11-21) IU l À1 . By contrast with ALT, miR-122 was not different when healthy controls were compared with CKD ( Figure 3B).…”

“…The Ago2-bound form of miR-122 may be more sensitive to enzymatic digestion compared with ECV-encapsulated miR-122. A priori it could be hypothesized that the ECV fraction would differ between patients with ESRD and healthy controls because work by our group [17], and others [18], has clearly demonstrated that systemically injected ECVs are excreted in urine. This would suggest that their clearance may be altered in ESRD.…”

Vesicles bearing gifts: the functional importance of micro-RNA transfer in extracellular vesicles in chronic kidney disease

“…There is also evidence that transport of EVs into cells is a specific and tightly regulated process. For example, the transport of renal tubular EVs carrying miR-503 into collecting duct epithelial cells has been shown to be hormonally regulated (118).…”

Renal extracellular vesicles: from physiology to clinical application

“…This process can be manipulated to deliver miRNA to collecting duct cells resulting in downregulation of target transcripts (Oosthuyzen et al . ). This study demonstrated that uEV signalling is a physiologically regulated process, which can be manipulated to deliver miRNA.…”