Adult stem cells have been studied as a promising therapeutic modality for the functional restoration of the damaged heart. In the present study, a strategy for enhancing the angiogenic efficacy of human mesenchymal stem cells (hMSCs) using micro-RNA was examined. We investigated whether micro-RNA-146a (miR-146a) influences the secretion of vascular endothelial growth factor (VEGF) and angiogenesis of MSCs. Our data indicated that miR-146a-transfected hMSCs (hMSCmiR-146a) decreased the expression of neurofibromin 2, an inhibitor of p21-activated kinase-1 (PAK1). miR-146a also increased the expression of Ras-related C3 botulinum toxin substrate 1 and PAK1, which are known to induce VEGF expression, and the formation of vascular branches was increased in hMSCmiR-146a compared to hMSCs treated with VEGF. VEGF and p-Akt were increased in hMSCmiR-146a. Furthermore, injection of hMSCmiR-146a after ischemia/reperfusion (I/R) injury led to a reduction of fibrosis area and increased VEGF expression, confirming the regenerative capacity such as reparative angiogenesis in the infarcted area. Cardiac functions in I/R injury were improved following injection of hMSCmiR-146a compared to the I/R group. Taken together, these data suggest that miR-146 is a novel microRNA that regulates VEGF expression, and its use may be an effective strategy for enhancing the therapeutic efficacy of hMSC transplantation into the I/R-injured heart.

Keywords:
Micro-RNA-146a, Neurofibromin 2, Vascular endothelial growth factor secretion, Angiogenesis
1.
Pagidipati NJ, Gaziano TA: Estimating deaths from cardiovascular disease: a review of global methodologies of mortality measurement. Circulation 2013;127:749-756.
2.
Gnecchi M, Danieli P, Cervio E: Mesenchymal stem cell therapy for heart disease. Vasc Pharmacol 2012;57:48-55.
3.
Thakker R, Yang P: Mesenchymal stem cell therapy for cardiac repair. Curr Treat Options Cardiovasc Med 2014;16:323.
4.
Choi YH, Kurtz A, Stamm C: Mesenchymal stem cells for cardiac cell therapy. Hum Gene Ther 2011;22:3-17.
5.
Song H, Song BW, Cha MJ, Choi IG, Hwang KC: Modification of mesenchymal stem cells for cardiac regeneration. Expert Opin Biol Ther 2010;10:309-319.
6.
Sun Q, Zhang Z, Sun Z: The potential and challenges of using stem cells for cardiovascular repair and regeneration. Genes Dis 2014;1:113-119.
7.
Baraniak PR, McDevitt TC: Stem cell paracrine actions and tissue regeneration. Regen Med 2010;5:121-143.
8.
Markel TA, Wang Y, Herrmann JL, Crisostomo PR, Wang M, Novotny NM, Herring CM, Tan J, Lahm T, Meldrum DR: VEGF is critical for stem cell-mediated cardioprotection and a crucial paracrine factor for defining the age threshold in adult and neonatal stem cell function. Am J Physiol Heart Circ Physiol 2008;295:H2308-H2314.
9.
Menasche P: Stem cells for clinical use in cardiovascular medicine: current limitations and future perspectives. Thromb Haemost 2005;94:697-701.
10.
Haider KH, Ashraf M: Preconditioning approach in stem cell therapy for the treatment of infarcted heart. Prog Mol Biol Transl Sci 2012;111:323-356.
11.
Abraham MR, Gerstenblith G: Preconditioning stem cells for cardiovascular disease: an important step forward. Circ Res 2007;100:447-449.
12.
Phillips MI, Tang Y: Genetic modification of stem cells for cardiac, diabetic, and hemophilia transplantation therapies. Prog Mol Biol Transl Sci 2012;111:285-304.
13.
Dzau VJ, Gnecchi M, Pachori AS: Enhancing stem cell therapy through genetic modification. J Am Coll Cardiol 2005;46:1351-1353.
14.
Cordes KR, Srivastava D: MicroRNA regulation of cardiovascular development. Circ Res 2009;104:724-732.
15.
Latronico MV, Condorelli G: MicroRNAs and cardiac pathology. Nat Rev Cardiol 2009;6:419-429.
16.
Small EM, Frost RJ, Olson EN: MicroRNAs add a new dimension to cardiovascular disease. Circulation 2010;121:1022-1032.
17.
Hua Z, Lv Q, Ye W, Wong CK, Cai G, Gu D, Ji Y, Zhao C, Wang J, Yang BB, Zhang Y: MiRNA-directed regulation of VEGF and other angiogenic factors under hypoxia. PLoS One 2006;1:e116.
18.
Boon RA: MicroRNAs control vascular endothelial growth factor signaling. Circ Res 2012;111:1388-1390.
19.
Koul D, Shen R, Garyali A, Ke LD, Liu TJ, Yung WK: MMAC/PTEN tumor suppressor gene regulates vascular endothelial growth factor-mediated angiogenesis in prostate cancer. Int J Oncol 2002;21:469-475.
20.
Rouleau GA, Merel P, Lutchman M, Sanson M, Zucman J, Marineau C, Hoang-Xuan K, Demczuk S, Desmaze C, Plougastel B, et al: Alteration in a new gene encoding a putative membrane-organizing protein causes neuro-fibromatosis type 2. Nature 1993;363:515-521.
21.
Golovnina K, Blinov A, Akhmametyeva EM, Omelyanchuk LV, Chang LS: Evolution and origin of merlin, the product of the neurofibromatosis type 2 (NF2) tumor-suppressor gene. BMC Evol Biol 2005;5:69.
22.
Hamaratoglu F, Willecke M, Kango-Singh M, Nolo R, Hyun E, Tao C, Jafar-Nejad H, Halder G: The tumour-suppressor genes NF2/merlin and expanded act through Hippo signalling to regulate cell proliferation and apoptosis. Nat Cell Biol 2006;8:27-36.
23.
Yu FX, Guan KL: The Hippo pathway: regulators and regulations. Genes Dev 2013;27:355-371.
24.
Ramos A, Camargo FD: The Hippo signaling pathway and stem cell biology. Trends Cell Biol 2012;22:339-346.
25.
Hirokawa Y, Tikoo A, Huynh J, Utermark T, Hanemann CO, Giovannini M, Xiao GH, Testa JR, Wood J, Maruta H: A clue to the therapy of neurofibromatosis type 2: NF2/merlin is a PAK1 inhibitor. Cancer J 2004;10:20-26.
26.
Kissil JL, Wilker EW, Johnson KC, Eckman MS, Yaffe MB, Jacks T: Merlin, the product of the NF2 tumor suppressor gene, is an inhibitor of the p21-activated kinase, Pak1. Mol Cell 2003;12:841-849.
27.
Bagheri-Yarmand R, Vadlamudi RK, Wang RA, Mendelsohn J, Kumar R: Vascular endothelial growth factor up-regulation via p21-activated kinase-1 signaling regulates heregulin-beta1-mediated angiogenesis. J Biol Chem 2000;275:39451-39457.
28.
Gururaj AE, Rayala SK, Kumar R: p21-activated kinase signaling in breast cancer. Breast Cancer Res 2005;7:5-12.
29.
Huang NF, Sievers RE, Park JS, Fang Q, Li S, Lee RJ: A rodent model of myocardial infarction for testing the efficacy of cells and polymers for myocardial reconstruction. Nat Protoc 2006;1:1596-1609.
30.
Bustelo XR, Sauzeau V, Berenjeno IM: GTP-binding proteins of the Rho/Rac family: regulation, effectors and functions in vivo. Bioessays 2007;29:356-370.
31.
Knaus UG, Wang Y, Reilly AM, Warnock D, Jackson JH: Structural requirements for PAK activation by Rac GTPases. J Biol Chem 1998;273:21512-21518.
32.
Abid MR, Guo S, Minami T, Spokes KC, Ueki K, Skurk C, Walsh K, Aird WC: Vascular endothelial growth factor activates PI3K/Akt/forkhead signaling in endothelial cells. Arterioscler Thromb Vasc Biol 2004;24:294-300.
33.
Liu P, Wilson MJ: miR-520c and miR-373 upregulate MMP9 expression by targeting mTOR and SIRT1, and activate the Ras/Raf/MEK/Erk signaling pathway and NF-kappaB factor in human fibrosarcoma cells. J Cell Physiol 2012;227:867-876.
34.
Pluda JM: Tumor-associated angiogenesis: mechanisms, clinical implications, and therapeutic strategies. Semin Oncol 1997;24:203-218.
35.
Carmeliet P: VEGF as a key mediator of angiogenesis in cancer. Oncology 2005;69(suppl 3):4-10.
36.
Mankame TP, Lingen MW: The RB tumor suppressor positively regulates transcription of the anti-angiogenic protein NOL7. Neoplasia 2012;14:1213-1222.
37.
Schwarte-Waldhoff I, Volpert OV, Bouck NP, Sipos B, Hahn SA, Klein-Scory S, Luttges J, Kloppel G, Graeven U, Eilert-Micus C, Hintelmann A, Schmiegel W: Smad4/DPC4-mediated tumor suppression through suppression of angiogenesis. Proc Natl Acad Sci USA 2000;97:9624-9629.
38.
Kim MS, Kwon HJ, Lee YM, Baek JH, Jang JE, Lee SW, Moon EJ, Kim HS, Lee SK, Chung HY, Kim CW, Kim KW: Histone deacetylases induce angiogenesis by negative regulation of tumor suppressor genes. Nat Med 2001;7:437-443.
39.
Na X, Wu G, Ryan CK, Schoen SR, di'Santagnese PA, Messing EM: Overproduction of vascular endothelial growth factor related to von Hippel-Lindau tumor suppressor gene mutations and hypoxia-inducible factor-1 alpha expression in renal cell carcinomas. J Urol 2003;170:588-592.
40.
Wong HK, Shimizu A, Kirkpatrick ND, Garkavtsev I, Chan AW, di Tomaso E, Klagsbrun M, Jain RK: Merlin/NF2 regulates angiogenesis in schwannomas through a Rac1/semaphorin 3F-dependent mechanism. Neoplasia 2012;14:84-94.
41.
Diebold I, Petry A, Djordjevic T, Belaiba RS, Fineman J, Black S, Schreiber C, Fratz S, Hess J, Kietzmann T, Gorlach A: Reciprocal regulation of Rac1 and PAK-1 by HIF-1alpha: a positive-feedback loop promoting pulmonary vascular remodeling. Antioxid Redox Signal 2010;13:399-412.
42.
Mahon PC, Hirota K, Semenza GL: FIH-1: a novel protein that interacts with HIF-1alpha and VHL to mediate repression of HIF-1 transcriptional activity. Genes Dev 2001;15:2675-2686.
43.
Li J, Huang J, Dai L, Yu D, Chen Q, Zhang X, Dai K: miR-146a, an IL-1beta responsive miRNA, induces vascular endothelial growth factor and chondrocyte apoptosis by targeting Smad4. Arthritis Res Ther 2012;14:R75.
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