Human extracellular microvesicles from renal tubules reverse kidney ischemia-reperfusion injury in rats
Fig 14
Rat renal tubular cell death by hypoxia/re-oxygenation and the role of human tubular cell exosomes.
Primary renal tubular cells were divided into four groups and cultured on 35 mm dishes in normoxic medium (38% O2 and 5% CO2) for 5 days. Two groups were continued in normoxic medium for 36 more hours (left, normoxia). One of these groups received exosomes during the final 24 hours (not shown). The other two groups were switched to hypoxic medium (1% O2 and 5% CO2) for 12 hours and then one hypoxic group was returned to normoxic medium for 24 more hours (hypoxia). One hypoxic group was also returned to normoxic medium which contained added human renal cell exosomes (right, HYPOXIA/EXO). Cells were then incubated with propidium iodide, fixed and individual dead cells visualized (red dots) and counted. The bar diagram summarizes the average number of dead cells measured in the dishes (n = 5). The number of dead cells in hypoxia/re-oxygenation (hypoxia) was higher than in normoxia, and cell death was significantly limited by exosomes (hypoxia/EXO). The bar diagram on right summarizes the enrichment of catalase (CAT) and superoxide dismutase (SOD) transcripts in exosomes with respect to the originating cells and normalized for actin mRNA. Both anti-oxidant transcripts were significantly higher in exosomes than in the originating cells (n = 5).