FIG. 1.

IPC induced miR-107 expression in MSC. (A) IPC significantly increased miR-107 expression in ^PCMSC as compared with native ^non-PCMSC. Cells treated with two cycles (PCx2) of 30 min A/R showed higher expression as compared with the cells treated with one cycle (PCx1). (B) Western blots showing significantly higher phosphorylation of Akt in ^PCMSC as compared with ^non-PCMSC, which was abrogated by pretreatment with 40 μM Wort for 45 min. (C) The induction of miR-107 in ^PCMSC was abrogated by pretreatment with Wort. Fold change for miR-107 in (A, C) was determined from densitometric ratio normalized to U6 expression and for pAkt in (B) from densitometric ratios between pAkt/total Akt in the respective samples. (D) Phase-contrast photomicrographs showed a better preserved morphology in the ^PCMSC treated with PCx2 as compared with PCx1 on subsequent exposure to 6 h of lethal anoxia. (E) Preconditioning attenuated cellular injury as examined by LDH assay subsequent to 6 h of lethal anoxia. Preconditioning by PCx2 was more effective in the protection of cells as compared with PCx1, using ^non-PCMSC as controls. Pretreatment with 40 μM Wort significantly abolished the effects of preconditioning. A/R, anoxia/re-oxygenation; IPC, ischemic preconditioning; LDH, lactate dehydrogenase; miR, microRNA; MSC, mesenchymal stem cells; ^PCMSC, preconditioned MSC; ^non-PCMSC, non-preconditioned MSC; Wort, Wortmannin.