MicroRNA-125b as a new potential biomarker on diagnosis of renal ischemia-reperfusion injury.

BACKGROUND: Acute renal failure is commonly seen in the perioperative period. Ischemia-reperfusion (IR) injury plays a major role in acute renal failure and delayed graft function. MicroRNAs (miRs), which are pivotal modulators of cell activities, offer a major opportunity for affective diagnosis and treatment strategies because they are tissue specific and in the center of gene expression modulation. The effect of bardoxolone methyl (BM) on miR-21, miR-223-5p, and miR-125b in renal IR injury was evaluated in this study.

METHODS: Wistar-Albino rats (12-16 wk old, weighing 300-350 g) were used in the study. Rats (n = 6) were randomized into three groups (control, IR, and BM + IR). Tissue levels of miRs were analyzed with reverse transcription polymerase chain reaction.

RESULTS: Significant reduction of urea and total oxidant status, increase of total antioxidant status, and oxidative stress index were identified in the IR + BM group compared with the IR group. Significant increases of miR-21 (2842.82-fold) and miR-125b (536.8-fold) were identified in the IR group compared with the control group; however, miR-223-5p levels did not show any significant difference. Also, miR-21 and miR-125b were significantly reduced in the IR + BM group compared with the IR group. Reduced histopathologic changes were observed in the IR + BM group. A significant decrease in the number of tunel-positive cells was identified in the IR + BM group compared with the IR group.

CONCLUSIONS: miR-125b was significantly increased in IR injury; thus, miR-125b can be a potential novel marker that can be used in diagnosis and treatment of renal IR injury. BM reduces miR-21 and miR-125b in case of IR injury and makes functional and histopathologic repairs.