MicroRNA-132 enhances transition from inflammation to proliferation during wound healing
Dongqing Li, … , Mona Ståhle, Ning Xu Landén
Dongqing Li, … , Mona Ståhle, Ning Xu Landén
Published June 29, 2015
Citation Information: J Clin Invest. 2015;125(8):3008-3026. https://doi.org/10.1172/JCI79052.
View: Text | PDF
Research Article Inflammation

MicroRNA-132 enhances transition from inflammation to proliferation during wound healing

Abstract

Wound healing is a complex process that is characterized by an initial inflammatory phase followed by a proliferative phase. This transition is a critical regulatory point; however, the factors that mediate this process are not fully understood. Here, we evaluated microRNAs (miRs) in skin wound healing and characterized the dynamic change of the miRNome in human skin wounds. miR-132 was highly upregulated during the inflammatory phase of wound repair, predominantly expressed in epidermal keratinocytes, and peaked in the subsequent proliferative phase. TGF-β1 and TGF-β2 induced miR-132 expression in keratinocytes, and transcriptome analysis of these cells revealed that miR-132 regulates a large number of immune response– and cell cycle–related genes. In keratinocytes, miR-132 decreased the production of chemokines and the capability to attract leukocytes by suppressing the NF-κB pathway. Conversely, miR-132 increased activity of the STAT3 and ERK pathways, thereby promoting keratinocyte growth. Silencing of the miR-132 target heparin-binding EGF-like growth factor (HB-EGF) phenocopied miR-132 overexpression in keratinocytes. Using mouse and human ex vivo wound models, we found that miR-132 blockade delayed healing, which was accompanied by severe inflammation and deficient keratinocyte proliferation. Together, our results indicate that miR-132 is a critical regulator of skin wound healing that facilitates the transition from the inflammatory to the proliferative phase.

Authors

Dongqing Li, Aoxue Wang, Xi Liu, Florian Meisgen, Jacob Grünler, Ileana R. Botusan, Sampath Narayanan, Erdem Erikci, Xi Li, Lennart Blomqvist, Lei Du, Andor Pivarcsi, Enikö Sonkoly, Kamal Chowdhury, Sergiu-Bogdan Catrina, Mona Ståhle, Ning Xu Landén

×

Figure 6

HB-EGF is targeted by miR-132 in keratinocytes.

Options: View larger image (or click on image) Download as PowerPoint
HB-EGF is targeted by miR-132 in keratinocytes. (A) Nucleotide resolutio...
(A) Nucleotide resolution of the predicted miR-132–binding sites in the 3′-UTR of HB-EGF mRNA: seed sequence (green letters) and mutated miR-132–binding sites (red letters). (B) Keratinocytes were transfected with luciferase reporter plasmid containing WT or mutant (Mut) HB-EGF 3′-UTR or empty vector (Vector), together with pre-miR-132 or pre-miR-Ctrl. Luciferase activity was measured 24 hours later (n = 3). (C) qRT-PCR analysis of HB-EGF mRNA expression in keratinocytes transfected with pre-miR-132/pre-miR-Ctrl/anti–miR-132/anti-miR-Ctrl for 48 hours, then treated with TNF-α for 24 hours (n = 3). Total and cell surface HB-EGF protein were analyzed by Western blotting in cells transfected with pre-miR-132/pre-miR-Ctrl (D) or with anti–miR-132/anti–miR-Ctrl (E). (F) HB-EGF shed into culture medium was analyzed by ELISA (n = 3). (G) qRT-PCR analysis of HB-EGF expression in wound biopsies from healthy donors (n = 7) at 0 hours, 24 hours, 1 week, and 1 month after injury. *P < 0.05, **P < 0.01, ***P < 0.001, and ****P < 0.0001 by Student’s t test.