Faculty Collaboration Database

miR-21 contributes to renal protection by targeting prolyl hydroxylase domain protein 2 in delayed ischaemic preconditioning. Nephrology (Carlton) 2017 May;22(5):366-373

Date

04/01/2016

Pubmed ID

27030384

DOI

10.1111/nep.12787

Scopus ID

2-s2.0-85017014820 (requires institutional sign-in at Scopus site)   18 Citations

Abstract

AIM: Upregulation of miR-21 in renal ischaemic preconditioning (IPC) was associated with increased hypoxia inducible factor (HIF)-1α expression. Hypoxic induction of HIF-1α is mediated by inhibition of prolyl hydroxylase domain protein 2 (PHD2) .We hypothesized that miR-21 regulated HIF-1α by targeting PHD2 in the renal IPC.

METHODS: Luciferase reporter assay examined if miR-21 target the 3'-untranslated region of PHD2. In vitro, human proximal tubular cell line (HK-2) was incubated in hypoxia or hypoxia/ reoxygenation condition. Kidneys of Mice were respectively subjected to ischaemia/reperfusion injury (IRI) and IPC. Locked nucleic acid (LNA) modified anti-miR-21 was used to knockdown miR-21. Serum creatinine and histological changes estimated the renal injury. Levels of HIF-1α, PHD2, VEGF and miR-21 were examined by western blot or real-time PCR.

RESULT: miR-21 targeting of PHD2 was confirmed by 3'-untranslated region reporter assay. miR-21 was significantly upregulated by hypoxia/reoxygenation in HK-2 cell, while PHD2 protein level decreased significantly. LNA anti-miR-21 significantly repressed miR-21 levels and increased the abundance of PHD2. In vivo, IPC upregulated miR-21 expression 24 h after the second ischaemia, while PHD2 expression decreased significantly with upregulation of HIF-1α protein and VEGF mRNA. MiR-21 induced by delayed IPC was effectively inhibited by the LNA anti-miR-21. With downregulation of miR-21, the protection of delayed IPC was attenuated and PHD2 protein was increased. Furthermore, upregulation of HIF-1α and VEGF were abolished after the LNA anti-miR-21 treatment.

CONCLUSION: miR-21 could protect kidney against IRI via HIF-1α by inhibiting its target PHD2.The study suggested a new relationship between miR-21 and HIF-1α.

Author List

Jiao X, Xu X, Fang Y, Zhang H, Liang M, Teng J, Ding X

MESH terms used to index this publication - Major topics in bold

3' Untranslated Regions
Animals
Binding Sites
Cell Hypoxia
Cell Line
Disease Models, Animal
Humans
Hypoxia-Inducible Factor 1, alpha Subunit
Hypoxia-Inducible Factor-Proline Dioxygenases
Ischemic Preconditioning
Kidney Diseases
Kidney Tubules, Proximal
Male
Mice, Inbred C57BL
MicroRNAs
Reperfusion Injury
Signal Transduction
Time Factors
Transfection
Vascular Endothelial Growth Factor A