Activation of IL-11/STAT3 pathway in preconditioned human skeletal myoblasts blocks apoptotic cascade under oxidant stress

Priming mesenchymal stem cells to develop "super stem cells"

The stem cell pre-treatment approaches at cellular and sub-cellular levels encompass physical manipulation of stem cells to growth factor treatment, genetic manipulation, and chemical and pharmacological treatment, each strategy having advantages and limitations. Most of these pre-treatment protocols are non-combinative. This editorial is a continuum of Li et al's published article and Wan et al's editorial focusing on the significance of pre-treatment strategies to enhance their stemness, immunoregulatory, and immunosuppressive properties. They have elaborated on the intricacies of the combinative pre-treatment protocol using pro-inflammatory cytokines and hypoxia. Applying a well-defined multi-pronged combinatorial strategy of mesenchymal stem cells (MSCs), pre-treatment based on the mechanistic understanding is expected to develop "Super MSCs", which will create a transformative shift in MSC-based therapies in clinical settings, potentially revolutionizing the field. Once optimized, the standardized protocols may be used with slight modifications to pre-treat different stem cells to develop "super stem cells" with augmented stemness, functionality, and reparability for diverse clinical applications with better outcomes.

Roles of IL-11 in the regulation of bone metabolism

Bone metabolism is the basis for maintaining the normal physiological state of bone, and imbalance of bone metabolism can lead to a series of metabolic bone diseases. As a member of the IL-6 family, IL-11 acts primarily through the classical signaling pathway IL-11/Receptors, IL-11 (IL-11R)/Glycoprotein 130 (gp130). The regulatory role of IL-11 in bone metabolism has been found earlier, but mainly focuses on the effects on osteogenesis and osteoclasis. In recent years, more studies have focused on IL-11's roles and related mechanisms in different bone metabolism activities. IL-11 regulates osteoblasts, osteoclasts, BM stromal cells, adipose tissue-derived mesenchymal stem cells, and chondrocytes. It's involved in bone homeostasis, including osteogenesis, osteolysis, bone marrow (BM) hematopoiesis, BM adipogenesis, and bone metastasis. This review exams IL-11's role in pathology and bone tissue, the cytokines and pathways that regulate IL-11 expression, and the feedback regulations of these pathways.

IL-11 ameliorates oxidative stress damage in neurons after spinal cord injury by activating the JAK/STAT signaling pathway

OBJECTIVE

Excess reactive oxygen species (ROS) generated by oxidative stress is a crucial factor affecting neuronal dysfunction after spinal cord injury (SCI). IL-11 has been reported to have antioxidative stress capacity. In the present study, we investigated the protective effect and mechanism of IL-11 against neuronal cell damage caused by oxidative imbalance.

METHODS

We established a H2O2-induced oxidative stress injury model in PC12 cells and observed the effects of IL-11 on cellular activity, morphology, oxidase and antioxidant enzymes, and ROS release. Furthermore, the effect of IL-11 on apoptosis of PC12 cells was assessed by flow cytometry, a TUNEL assay and Western blotting. Transcriptome analysis and rescue experiments revealed the mechanism by which IL-11 protects neurons from oxidative stress damage. For the in vivo investigation, an adenovirus-mediated IL-11 overexpression SCI rat model was constructed to validate the beneficial effect of IL-11 against SCI.

RESULTS

IL-11 significantly improved the viability and enhanced the antioxidant activity of H2O2-treated PC12 cells while reducing ROS release. In addition, IL-11 reduced H2O2-induced PC12 cell apoptosis. Transcriptome analysis revealed that the JAK/STAT pathway may be related to the antioxidant activity of IL-11. Treatment with a JAK/STAT inhibitor (Stattic) exacerbated the oxidative damage induced by H2O2 and attenuated the protective effects of IL-11. The results of in vivo studies showed that IL-11 prevented neuronal apoptosis due to oxidative imbalance and promoted the restoration of motor function in SCI rats by activating the JAK/STAT signaling pathway.

CONCLUSION

IL-11 inhibited oxidative stress-induced neuronal apoptosis at least in part by activating the JAK/STAT signaling pathway and further promoted the recovery of motor function. These findings suggest that IL-11 may be an effective target for the treatment for SCI.

Interleukin-11 regulates the fate of adipose-derived mesenchymal stem cells via STAT3 signalling pathways

Objective

Adipose‐derived mesenchymal stem cells (ADSCs) offer great promise as cell therapy for ischaemic diseases. Due to their poor survival in the ischaemic environment, the therapeutic efficacy of ADSCs is still relatively low. Interleukin‐11 (IL‐11) has been shown to play a key role in promoting cell proliferation and protecting cells from oxidative stress injury. The aim of this study was to determine whether IL‐11 could improve therapeutic efficacy of ADSCs in ischaemic diseases.

Methods and Results

ADSCs were prepared from inguinal subcutaneous adipose tissue and exposed to hypoxic environment. The protein expression of IL‐11 was decreased after hypoxic treatment. In addition, ADSCs viability was increased after IL‐11 treatment under hypoxia. Moreover, IL‐11 enhanced ADSCs viability in a dose‐dependent manner under normoxia. Importantly, IL‐11 promoted ADSCs proliferation and migration and protected ADSCs against hydrogen peroxide‐induced cellular death. Notably, IL‐11 enhanced ADSCs proliferation and migration, also promoted cell survival and apoptosis resistance by STAT3 signalling. In vivo, mice were subjected to limb ischaemia and treated with IL‐11 overexpression ADSCs and control ADSCs. IL‐11 overexpression ADSCs improved perfusion recovery in the ischaemic muscles.

Conclusions

We provide the evidence that IL‐11 promoted ADSCs proliferation, stimulated ADSCs migration and attenuated ADSCs apoptosis by activation of STAT3 signalling. These results suggest that IL‐11 facilitated ADSCs engraftment in ischaemic tissue, thereby enhanced ADSCs therapeutic efficacy.

Insight into adipokines to optimize therapeutic effects of stem cell for tissue regeneration

Stem cell therapy is considered as a promising regenerative medicine for repairing and treating damaged tissues and/or preventing various diseases. But there are still some obstacles such as low cell migration, poor stem cell engraftment and decreased cell survival that need to be overcome before transplantation. Therefore, a large body of studies has focused on improving the efficiency of stem cell therapy. For instance, preconditioning of stem cells has emerged as an effective strategy to reinforce therapeutic efficacy. Adipokines are signaling molecules, secreted by adipose tissue, which regulate a variety of biological processes in adipose tissue and other organs including the brain, liver, and muscle. In this review article, we shed light on the biological effects of some adipokines including apelin, oncostatin M, omentin-1 and vaspin on stem cell therapy and the most recent preclinical advances in our understanding of how these functions ameliorate stem cell therapy outcome.

Nicorandil potentiates sodium butyrate induced preconditioning of neurons and enhances their survival upon subsequent treatment with H2O2

Background

Extensive loss of donor neural stem cell (NSCs) due to ischemic stress and low rate of differentiation at the site of cell graft are two of the major issues that hamper optimal outcome in NSCs transplantation studies. Given that histone deacetylases (HDACs) modulate various cellular processes by deacetylating histones and non-histone proteins, we hypothesized that combined treatment with small molecules, sodium butyrate (NaB; a known HDAC inhibitor) and nicorandil, will enhance the rate neuronal differentiation of NSCs besides their preconditioning to resist oxidative stress.

Methods

NSCs derived from 14-day old Sprague Dawley rat ganglion eminence were characterized for tri-lineage differentiation. Treatment with 1 mM NaB significantly changed their culture characteristics while continuous treatment for 10 days enhanced their neural differentiation. NaB treatment also preconditioned the cells for their resistance to oxidative stress.

Results

The highest rate of neural differentiation and preconditioning effect was achieved when the NSCs were treated concomitantly with NaB and nicorandil. Cell proliferation assay showed that concomitant treatment with NaB and nicorandil retarded their rate of proliferation.

Conclusion

These data conclude that preconditioning of NSCs with NaB and nicorandil effectively enhances their differentiation capacity besides preconditioning the cells to support their survival under ischemic conditions.

Electronic supplementary material

The online version of this article (10.1186/s40035-017-0097-1) contains supplementary material, which is available to authorized users.

TMED3 promotes hepatocellular carcinoma progression via IL-11/STAT3 signaling

Transmembrane p24 trafficking protein 3(TMED3) is a metastatic suppressor in colon cancer, but its function in the progression of hepatocellular carcinoma (HCC) is unknown. Here, we report that TMED3 was up-regulated in HCC and portal vein tumor thrombus. TMED3 up-regulation in HCC was significantly correlated with aggressive characteristics and predicted poor prognosis in HCC patients. TMED3 overexpression in HCC cell lines promoted cell migration and invasion. In contrast, TMED3 knockdown suppressed HCC metastasis both in vitro and in vivo. Gene microarray analysis revealed decreased IL-11 expression in TMED3-knockdown cells. We propose that TMED3 promotes HCC metastasis through IL-11/STAT3 signaling. Taken together, these findings demonstrate that TMED3 promotes HCC metastasis and is a potential prognostic biomarker in HCC.

Cardiopulmonary Bypass Decreases Activation of the Signal Transducer and Activator of Transcription 3 (STAT3) Pathway in Diabetic Human Myocardium

BACKGROUND

Cardiopulmonary bypass (CPB) is associated with increased myocardial oxidative stress and apoptosis in diabetic patients. A mechanistic understanding of this relationship could have therapeutic value. To establish a possible mechanism, we compared the activation of the cardioprotective signal transducer and activator of transcription 3 (STAT3) pathway between patients with uncontrolled diabetes (UD) and nondiabetic (ND) patients.

METHODS

Right atrial tissue and serum were collected before and after CPB from 80 patients, 39 ND and 41 UD (HbA1c ≥ 6.5), undergoing cardiac operations. The samples were evaluated with Western blotting, immunohistochemistry, and microarray.

RESULTS

On Western blot, leptin levels were significantly increased in ND post-CPB (p < 0.05). Compared with ND, the expression of Janus kinase 2 and phosphorylation (p-) of STAT3 was significantly decreased in UD (p < 0.05). The apoptotic proteins p-Bc12/Bc12 and caspase 3 were significantly increased (p < 0.05), antiapoptotic proteins Mcl-1, Bcl-2, and p-Akt were significantly decreased (p < 0.05) in UD compared with ND. The microarray data suggested significantly increased expression of interleukin-6 R, proapoptotic p-STAT1, caspase 9, and decreased expression of Bc12 and protein inhibitor of activated STAT1 antiapoptotic genes (p = 0.05) in the UD patients. The oxidative stress marker nuclear factor-κB was significantly higher (p < 0.05) in UD patients post-CPB compared with the pre-CPB value, but was decreased, albeit insignificantly, in ND patients post-CPB.

CONCLUSIONS

Compared with ND, UD myocardium demonstrated attenuation of the cardioprotective STAT3 pathway. Identification of this mechanism offers a possible target for therapeutic modulation.

Preconditioning strategy in stem cell transplantation therapy

Stem cell transplantation therapy has emerged as a promising regenerative medicine for ischemic stroke and other neurodegenerative disorders. However, many issues and problems remain to be resolved before successful clinical applications of the cell-based therapy. To this end, some recent investigations have sought to benefit from well-known mechanisms of ischemic/hypoxic preconditioning. Ischemic/hypoxic preconditioning activates endogenous defense mechanisms that show marked protective effects against multiple insults found in ischemic stroke and other acute attacks. As in many other cell types, a sub-lethal hypoxic exposure significantly increases the tolerance and regenerative properties of stem cells and progenitor cells. So far, a variety of preconditioning triggers have been tested on different stem cells and progenitor cells. Preconditioned stem cells and progenitors generally show much better cell survival, increased neuronal differentiation, enhanced paracrine effects leading to increased trophic support, and improved homing to the lesion site. Transplantation of preconditioned cells helps to suppress inflammatory factors and immune responses, and promote functional recovery. Although the preconditioning strategy in stem cell therapy is still an emerging research area, accumulating information from reports over the last few years already indicates it as an attractive, if not essential, prerequisite for transplanted cells. It is expected that stem cell preconditioning and its clinical applications will attract more attention in both the basic research field of preconditioning as well as in the field of stem cell translational research. This review summarizes the most important findings in this active research area, covering the preconditioning triggers, potential mechanisms, mediators, and functional benefits for stem cell transplant therapy.

Cell based therapies for ischemic stroke: from basic science to bedside

Cell therapy is emerging as a viable therapy to restore neurological function after stroke. Many types of stem/progenitor cells from different sources have been explored for their feasibility and efficacy for the treatment of stroke. Transplanted cells not only have the potential to replace the lost circuitry, but also produce growth and trophic factors, or stimulate the release of such factors from host brain cells, thereby enhancing endogenous brain repair processes. Although stem/progenitor cells have shown a promising role in ischemic stroke in experimental studies as well as initial clinical pilot studies, cellular therapy is still at an early stage in humans. Many critical issues need to be addressed including the therapeutic time window, cell type selection, delivery route, and in vivo monitoring of their migration pattern. This review attempts to provide a comprehensive synopsis of preclinical evidence and clinical experience of various donor cell types, their restorative mechanisms, delivery routes, imaging strategies, future prospects and challenges for translating cell therapies as a neurorestorative regimen in clinical applications.

IL-11/IL11RA receptor mediated signaling: a web accessible knowledgebase

Abstract Interleukin-11 (IL-11) is a pleiotropic cytokine that belongs to gp130 family. It plays a significant role in the synthesis and maturation of hematopoietic cells, inhibition of adipogenesis, regulation of embryo implantation, and trophoblasts invasion. Although IL-11 signaling has been described in several biological processes, a centralized resource documenting these molecular reactions induced by IL-11 is not publicly available. In the current study, we have manually annotated the molecular reactions and interactions induced by IL-11 from literature available. We have documented 40 unique molecules involved in 18 protein-protein interactions, 26 enzyme-substrate reactions, 7 translocation events, and 4 activation/ inhibition reactions. We have also annotated 23 genes reported to be differentially regulated under IL-11 stimulation. We have enabled the data availability in standard exchange formats from 'NetPath', a repository for signaling pathways. We believe that this will help in the identification of potential therapeutic targets in IL-11-associated disorders.

Preconditioning approach in stem cell therapy for the treatment of infarcted heart

Nearly two decades of research in regenerative medicine have been focused on the development of stem cells as a therapeutic option for treatment of the ischemic heart. Given the ability of stem cells to regenerate the damaged tissue, stem-cell-based therapy is an ideal approach for cardiovascular disorders. Preclinical studies in experimental animal models and clinical trials to determine the safety and efficacy of stem cell therapy have produced encouraging results that promise angiomyogenic repair of the ischemically damaged heart. Despite these promising results, stem cell therapy is still confronted with issues ranging from uncertainty about the as-yet-undetermined "ideal" donor cell type to the nonoptimized cell delivery strategies to harness optimal clinical benefits. Moreover, these lacunae have significantly hampered the progress of the heart cell therapy approach from bench to bedside for routine clinical applications. Massive death of donor cells in the infarcted myocardium during acute phase postengraftment is one of the areas of prime concern, which immensely lowers the efficacy of the procedure. An overview of the published data relevant to stem cell therapy is provided here and the various strategies that have been adopted to develop and optimize the protocols to enhance donor stem cell survival posttransplantation are discussed, with special focus on the preconditioning approach.