Interleukin-10 Deficiency Impairs Bone Marrow–Derived Endothelial Progenitor Cell Survival and Function in Ischemic Myocardium

Abstract

Rationale Endothelial progenitor cell (EPC) survival and function in the injured myocardium is adversely influenced by hostile microenvironment like ischemia, hypoxia and inflammatory response, thereby compromising full benefits of EPC-mediated myocardial repair. Objective We hypothesized that interleukin-10 (IL-10) modulates EPC biology leading to enhanced survival and function following transplantation in the ischemic myocardium. Methods and Results Myocardial infarction (MI)-induced mobilization of bone marrow EPC (Sca-1+Flk1+ cells) into the circulation was significantly impaired in IL-10 KO-mice. Bone marrow transplantation (BMT) to replace IL-10 KO-marrow with WT-marrow attenuated these effects. Impaired mobilization was associated with lower SDF-1 expression levels in the myocardium of KO-mice. Interestingly, SDF-1 administration reversed mobilization defect in KO-mice. In vitro, hypoxia-mediated increases in CXCR4 expression and cell survival were lower in IL-10-deficient-EPCs. Furthermore, SDF-1-induced migration of WT-EPCs was inhibited by AMD3100, an inhibitor of CXCR4. To further study the effect of IL-10 on in vivo EPC survival and engraftment into vascular structures, GFP-labeled EPC were injected intramyocardially after induction of MI, and the mice were treated with either saline or recombinant IL-10. IL-10-treated group showed increased retention of transplanted EPCs in the myocardium and was associated with significantly reduced EPC apoptosis post-MI. Interestingly, increased EPC retention and their association with the vascular structures was observed in IL-10 treated mice. Increased EPC survival and angiogenesis in the myocardium of IL-10-treated mice corroborated with improved LV function, reduced infarct size and fibrosis in the myocardium. In vitro, IL-10-induced increase in VEGF expression in WT-EPC was abrogated by STAT3 inhibitor suggesting IL-10 signals via STAT3 activation. Conclusions Taken together, our studies demonstrate that MI-induced EPC mobilization was impaired in IL-10 KO-mice and that IL-10 increases EPC survival and function possibly via activation of STAT3/VEGF signaling cascades, leading to attenuation of MI-induced LV dysfunction and remodeling.

Interleukin-10 overexpression improves the function of endothelial progenitor cells stimulated with TNF-α through the activation of the STAT3 signaling pathway

“…Several studies have demonstrated that BM-mononuclear cells (MNCs), as well as mesenchymal stem cells (MSCs), have the ability to immunoregulate and improve tissue repair through IL-10 secretion (9)(10)(11). A further study by Krishnamurthy et al (12) demonstrated that IL-10 has a role on EPC mobilization following myocardial injury. Therefore, we hypothesized that IL-10 modulates EPC biology and enhances its function via activation of the signal transducer and activator of transcription 3 (STAT3) signaling pathway.…”

Alcohol Consumption Negates Estrogen-mediated Myocardial Repair in Ovariectomized Mice by Inhibiting Endothelial Progenitor Cell Mobilization and Function

“…Bone Marrow Transplant (BMT) and Identification of Transgenic EPCs in Myocardium-BMTs were conducted as reported previously (15,24). Briefly, recipient C57BL/6 mice were lethally irradiated with a 9.0-gray dose followed by a BMT from a transgenic donor mouse expressing ␤-gal encoded by the lacZ gene under the transcriptional regulation of an endothelial-specific promoter Tie-2 (Tie2-lacZ mice) via an intravenous injection of 2 ϫ 10 6 donor BM cells.…”

“…Bone Marrow Cell Isolation and EPC Culture-EPC isolation, ex vivo expansion, and culture of EPCs was performed as described previously (24). In brief, bone marrow mononuclear cells were isolated from mice by density gradient centrifugation with Histopaque-1083 (Sigma) and macrophage-depleted by allowing isolated cells to attach to uncoated plates.…”

“…Harvest of Cardiac Tissue, Histology, and Immunofluorescent Assessments-All hearts were harvested after the 28-day echocardiographic analysis as described previously (25,26), embedded in paraffin, and cut into sections for immunohistochemical staining as described previously (22)(23)(24)27). Specimens were fixed in 10% (v/v) buffered formaldehyde, dehydrated with graded ethanol series, and embedded in paraffin.…”

Imaging Angiogenesis Using 99mTc-Macroaggregated Albumin Scintigraphy in Patients with Peripheral Artery Disease

“…Recently, the therapeutic focus has shifted to regenerative techniques that induce angiogenesis. Human bone marrow is a diverse reservoir for several progenitor cell populations, including endothelial progenitor cells (EPCs) (3). The use of progenitor cells (stem cells) for cell-based regenerative therapy is promising because of the high proliferative capacity and multilineage differentiation potential of the progenitor cells and also because of their contribution to angiogenesis or arteriogenesis (4) through the recruitment of EPCs (5) and their functionality and secretion of growth factors (6) and cytokines (7)(8)(9) that promote cell survival.…”