Spontaneous apoptosis of cells in therapeutic stem cell preparation exert immunomodulatory effects through release of phosphatidylserine

AbstractMesenchymal stem cell (MSC)-mediated immunomodulation has been harnessed for the treatment of human diseases, but its underlying mechanism has not been fully understood. Dead cells, including apoptotic cells have immunomodulatory properties. It has been repeatedly reported that the proportion of nonviable MSCs in a MSC therapeutic preparation varied from 5~50% in the ongoing clinical trials. It is conceivable that the nonviable cells in a MSC therapeutic preparation may play a role in the therapeutic effects of MSCs. We found that the MSC therapeutic preparation in the present study had about 5% dead MSCs (DMSCs), characterized by apoptotic cells. Namely, 1 × 106 MSCs in the preparation contained about 5 × 104 DMSCs. We found that the treatment with even 5 × 104 DMSCs alone had the equal therapeutic effects as with 1 × 106 MSCs. This protective effect of the dead MSCs alone was confirmed in four mouse models, including concanavalin A (ConA)- and carbon tetrachloride (CCl4)-induced acute liver injury, LPS-induced lung injury and spinal cord injury. We also found that the infused MSCs died by apoptosis in vivo. Furthermore, the therapeutic effect was attributed to the elevated level of phosphatidylserine (PS) upon the injection of MSCs or DMSCs. The direct administration of PS liposomes (PSLs) mimic apoptotic cell fragments also exerted the protective effects as MSCs and DMSCs. The Mer tyrosine kinase (MerTK) deficiency or the knockout of chemokine receptor C–C motif chemokine receptor 2 (CCR2) reversed these protective effects of MSCs or DMSCs. These results revealed that DMSCs alone in the therapeutic stem cell preparation or the apoptotic cells induced in vivo may exert the same immunomodulatory property as the “living MSCs preparation” through releasing PS, which was further recognized by MerTK and participated in modulating immune cells.

Download Full-text

Neural stem cell-derived exosomes facilitate spinal cord functional recovery after injury by promoting angiogenesis

Experimental Biology and Medicine ◽

10.1177/1535370219895491 ◽

2020 ◽

Vol 245 (1) ◽

pp. 54-65 ◽

Cited By ~ 6

Author(s):

Dong Zhong ◽

Yong Cao ◽

Cheng-Jun Li ◽

Miao Li ◽

Zi-Jie Rong ◽

...

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

Functional Recovery ◽

Underlying Mechanism ◽

Regeneration Ability ◽

Therapeutic Effects ◽

Cord Injury ◽

Angiogenic Effect

Acute traumatic spinal cord injury is a devastating event without effective therapeutic approach. The feeble plasticity of spinal cord microvascular endothelial cells (SCMECs) after trauma is one of the major causes for the exacerbation of spinal cord injury. Therefore, improving the plasticity and regeneration of SCMECs is crucial to promote recovery after spinal cord injury. For the present study, we explored the influence of exosomes derived from neural stem cells (NSCs-Exos) on the spinal cord microvascular regeneration after spinal cord injury and determined the underlying mechanisms. After the primary NSCs and SCMECs were extracted, exosomes were isolated from NSCs conditioned medium and used to co-incubated with the SCMECs in vitro, and then the effect of exosomes on the angiogenic activities of SCMECs was measured. The candidate molecules involved in the NSCs-Exos-mediated angiogenesis were screened using Western blotting. The effect of NSCs-Exos on angiogenesis and spinal cord functional recovery after injury in vivo was analyzed. The results demonstrated that NSCs-Exos could enhance the angiogenic activities of SCMECs, and were highly enriched in VEGF-A. The level of VEGF-A was downregulated in NSCsshVEGF-A-Exos and the pro-angiogenic effects on cocultured SCMECs were inhibited. Furthermore, NSCs-Exos significantly accelerated the microvascular regeneration, reduced the spinal cord cavity, and improved the Basso mouse scale scores in spinal cord injury mice. This work provides the evidence of the underlying mechanism of NSCs-Exos-mediated angiogenesis and suggests a novel therapeutic target for spinal cord injury. Impact statement The feeble plasticity of SCMECs after trauma is one of the major causes for the exacerbation of SCI. Therefore, improving the regeneration ability of SCMECs is crucial to promote spinal cord functional recovery after injury. Our current study uncovered that NSCs-Exos could promote SCMECs migration, tube formation and proliferation in vitro, and further identified that exosomal VEGF-A mediated the pro-angiogenic effect. Furthermore, we observed a remarkable microvascular density increase, spinal cord cavity shrinkage, and motor function recovery in SCI mice treated with NSCs-Exos, which confirmed the therapeutic effects of NSCs-Exos to alleviate SCI. Downregulating VEGF-A partially abolished these effects of NSCs-Exos. This is the first study to reveal that NSCs-Exos has the pro-angiogenic effect on SCMECs by transferring VEGF-A and promote microvascular regeneration and tissue healing, indicating that NSCs-Exos can become a promising therapeutic bioagent for facilitating the functional recovery of SCI.

Download Full-text

Propofol attenuates lung ischemia/reperfusion injury though the involvement of the MALAT1/microRNA-144/GSK3β axis

Molecular Medicine ◽

10.1186/s10020-021-00332-0 ◽

2021 ◽

Vol 27 (1) ◽

Author(s):

Jian-Ping Zhang ◽

Wei-Jing Zhang ◽

Miao Yang ◽

Hua Fang

Keyword(s):

Cell Apoptosis ◽

Ischemia Reperfusion Injury ◽

Glycogen Synthase ◽

Ischemia Reperfusion ◽

Inflammatory Factors ◽

Therapeutic Effects ◽

Protective Effects ◽

Loss Of Function

Abstract Background Propofol, an intravenous anesthetic, was proven to protect against lung ischemia/reperfusion (I/R) injury. However, the detailed mechanism of Propofol in lung I/R injury is still elusive. This study was designed to explore the therapeutic effects of Propofol, both in vivo and in vitro, on lung I/R injury and the underlying mechanisms related to metastasis-associated lung adenocarcinoma transcript 1 (MALAT1)/microRNA-144 (miR-144)/glycogen synthase kinase-3β (GSK3β). Methods C57BL/6 mice were used to establish a lung I/R injury model while pulmonary microvascular endothelial cells (PMVECs) were constructed as hypoxia/reperfusion (H/R) cellular model, both of which were performed with Propofol treatment. Gain- or loss-of-function approaches were subsequently employed, followed by observation of cell apoptosis in lung tissues and evaluation of proliferative and apoptotic capabilities in H/R cells. Meanwhile, the inflammatory factors, autophagosomes, and autophagy-related proteins were measured. Results Our experimental data revealed that Propofol treatment could decrease the elevated expression of MALAT1 following I/R injury or H/R induction, indicating its protection against lung I/R injury. Additionally, overexpressing MALAT1 or GSK3β promoted the activation of autophagosomes, proinflammatory factor release, and cell apoptosis, suggesting that overexpressing MALAT1 or GSK3β may reverse the protective effects of Propofol against lung I/R injury. MALAT1 was identified to negatively regulate miR-144 to upregulate the GSK3β expression. Conclusion Overall, our study demonstrated that Propofol played a protective role in lung I/R injury by suppressing autophagy and decreasing release of inflammatory factors, with the possible involvement of the MALAT1/miR-144/GSK3β axis.

Download Full-text

Enhancing therapeutic effects and in vivo tracking of adipose tissue derived mesenchymal stem cells for liver injury using bioorthogonal click chemistry

Nanoscale ◽

10.1039/d0nr07272a ◽

2020 ◽

Author(s):

Naishun Liao ◽

Da Zhang ◽

Ming Wu ◽

Huang-Hao Yang ◽

Xiaolong Liu ◽

...

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

Adipose Tissue ◽

Stem Cell ◽

Liver Injury ◽

Mesenchymal Stem Cell ◽

Liver Diseases ◽

Therapeutic Effects

Adipose tissue derived mesenchymal stem cell (ADSC)-based therapy is attractive for liver diseases, but the long-term therapeutic outcome is still far from satisfaction due to low hepatic engraftment efficiency of...

Download Full-text

Mesenchymal Stromal (stem) Cell (MSC) therapy modulates miR-193b-5p expression to attenuate sepsis-induced acute lung injury

European Respiratory Journal ◽

10.1183/13993003.04216-2020 ◽

2021 ◽

pp. 2004216

Author(s):

Claudia C. dos Santos ◽

Hajera Amatullah ◽

Chirag M. Vaswani ◽

Tatiana Maron-Gutierrez ◽

Michael Kim ◽

...

Keyword(s):

Stem Cell ◽

Lung Injury ◽

Conditioned Media ◽

Therapeutic Effects ◽

Host Immune System ◽

Gene And Protein Expression ◽

Stromal Stem Cell ◽

Mesenchymal Stromal Stem Cell ◽

Deficient Mice

Although mesenchymal stromal (stem) cell (MSC) administration attenuates sepsis-induced lung injury in pre-clinical models, the mechanism(s) of action and host immune system contributions to its therapeutic effects, remain elusive. We show that treatment with MSCs decreased expression of host-derived microRNA (miR)-193b-5p and increased expression of its target gene, the tight junctional protein occludin (Ocln), in lungs from septic mice. Mutating the Ocln 3′ UTR miR-193b-5p binding sequence impaired binding to Ocln mRNA. Inhibition of miR-193b-5p in human primary pulmonary microvascular endothelial cells (HPMECs) prevents tumor necrosis factor (TNF)-induced decrease in Ocln gene and protein expression and loss of barrier function. MSC conditioned media mitigated TNF-induced miR-193b-5p upregulation and Ocln downregulation in vitro. When administered in vivo, MSC conditioned media recapitulated the effects of MSC administration on pulmonary miR-193b-5p and Ocln expression. MiR-193b deficient mice were resistant to pulmonary inflammation and injury induced by LPS instillation. Silencing of Ocln in miR-193b deficient mice partially recovered the susceptibility to LPS-induced lung injury. In vivo inhibition of miR-193b-5p protected mice from endotoxin-induced lung injury. Finally, the clinical significance of these results was supported by the finding of increased miR-193b-5p expression levels in lung autopsy samples from Acute Respiratory Distress Syndrome patients who died with diffuse alveolar damage.

Download Full-text

Molecular Imaging in Traditional Chinese Medicine Therapy for Neurological Diseases

BioMed Research International ◽

10.1155/2013/608430 ◽

2013 ◽

Vol 2013 ◽

pp. 1-11 ◽

Cited By ~ 15

Author(s):

Zefeng Wang ◽

Haitong Wan ◽

Jinhui Li ◽

Hong Zhang ◽

Mei Tian

Keyword(s):

Chinese Medicine ◽

Molecular Imaging ◽

Traditional Chinese Medicine ◽

Neurological Disorders ◽

Neurological Diseases ◽

Chinese Herb ◽

Public Health Care ◽

Therapeutic Effects ◽

Cord Injury

With the speeding tendency of aging society, human neurological disorders have posed an ever increasing threat to public health care. Human neurological diseases include ischemic brain injury, Alzheimer’s disease, Parkinson’s disease, and spinal cord injury, which are induced by impairment or specific degeneration of different types of neurons in central nervous system. Currently, there are no more effective treatments against these diseases. Traditional Chinese medicine (TCM) is focused on, which can provide new strategies for the therapy in neurological disorders. TCM, including Chinese herb medicine, acupuncture, and other nonmedication therapies, has its unique therapies in treating neurological diseases. In order to improve the treatment of these disorders by optimizing strategies using TCM and evaluate the therapeutic effects, we have summarized molecular imaging, a new promising technology, to assess noninvasively disease specific in cellular and molecular levels of living models in vivo, that was applied in TCM therapy for neurological diseases. In this review, we mainly focus on applying diverse molecular imaging methodologies in different TCM therapies and monitoring neurological disease, and unveiling the mysteries of TCM.

Download Full-text

Overexposure to apoptosis via disrupted glial specification perturbs Drosophila macrophage function and reveals roles of the CNS during injury

10.1101/2020.03.04.977546 ◽

2020 ◽

Cited By ~ 1

Author(s):

Emma Louise Armitage ◽

Hannah Grace Roddie ◽

Iwan Robert Evans

Keyword(s):

Inflammatory Responses ◽

Apoptotic Cell ◽

Calcium Waves ◽

Apoptotic Cells ◽

Phagocytic Cells ◽

Macrophage Function ◽

Apoptotic Cell Clearance ◽

Cell Clearance ◽

Wound Responses

AbstractApoptotic cell clearance by phagocytes is a fundamental process during development, homeostasis and the resolution of inflammation. However, the demands placed on phagocytic cells such as macrophages by this process, and the limitations these interactions impose on subsequent cellular behaviours are not yet clear. Here we seek to understand how apoptotic cells affect macrophage function in the context of a genetically-tractable Drosophila model in which macrophages encounter excessive amounts of apoptotic cells. We show that loss of the glial transcription factor repo, and corresponding removal of the contribution these cells make to apoptotic cell clearance, causes macrophages in the developing embryo to be challenged with large numbers of apoptotic cells. As a consequence, macrophages become highly vacuolated with cleared apoptotic cells and their developmental dispersal and migration is perturbed. We also show that the requirement to deal with excess apoptosis caused by a loss of repo function leads to impaired inflammatory responses to injury. However, in contrast to migratory phenotypes, defects in wound responses cannot be rescued by preventing apoptosis from occurring within a repo mutant background. In investigating the underlying cause of these impaired inflammatory responses, we demonstrate that wound-induced calcium waves propagate into surrounding tissues, including neurons and glia of the ventral nerve cord, which exhibit striking calcium waves on wounding, revealing a previously unanticipated contribution of these cells during responses to injury. Taken together these results demonstrate important insights into macrophage biology and how repo mutants can be used to study macrophage-apoptotic cell interactions in the fly embryo.Furthermore, this work shows how these multipurpose cells can be ‘overtasked’ to the detriment of their other functions, alongside providing new insights into which cells govern macrophage responses to injury in vivo.

Download Full-text

Protective effects of ginsenoside Rg1 on intestinal ischemia/reperfusion injury-induced oxidative stress and apoptosis via activation of the Wnt/β-catenin pathway

Scientific Reports ◽

10.1038/srep38480 ◽

2016 ◽

Vol 6 (1) ◽

Cited By ~ 27

Author(s):

Guo Zu ◽

Jing Guo ◽

Ningwei Che ◽

Tingting Zhou ◽

Xiangwen Zhang

Keyword(s):

Signaling Pathway ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Inflammatory Factors ◽

Therapeutic Effects ◽

Protective Effects ◽

Ginsenoside Rg1 ◽

Intestinal Ischemia Reperfusion

Abstract Ginsenoside Rg1 (Rg1) is one of the major bioactive ingredients in Panax ginseng, and it attenuates inflammation and apoptosis. The aims of our study were to explore the potential of Rg1 for the treatment of intestinal I/R injury and to determine whether the protective effects of Rg1 were exerted through the Wnt/β-catenin signaling pathway. In this study, Rg1 treatment ameliorated inflammatory factors, ROS and apoptosis that were induced by intestinal I/R injury. Cell viability was increased and cell apoptosis was decreased with Rg1 pretreatment following hypoxia/reoxygenation (H/R) in the in vitro study. Rg1 activated the Wnt/β-catenin signaling pathway in both the in vivo and in vitro models, and in the in vitro study, the activation was blocked by DKK1. Our study provides evidence that pretreatment with Rg1 significantly reduces ROS and apoptosis induced by intestinal I/R injury via activation of the Wnt/β-catenin pathway. Taken together, our results suggest that Rg1 could exert its therapeutic effects on intestinal I/R injury through the Wnt/β-catenin signaling pathway and provide a novel treatment modality for intestinal I/R injury.

Download Full-text

Fully reduced HMGB1 accelerates the regeneration of multiple tissues by transitioning stem cells to GAlert

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1802893115 ◽

2018 ◽

Vol 115 (19) ◽

pp. E4463-E4472 ◽

Cited By ~ 46

Author(s):

Geoffrey Lee ◽

Ana Isabel Espirito Santo ◽

Stefan Zwingenberger ◽

Lawrence Cai ◽

Thomas Vogl ◽

...

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Tissue Regeneration ◽

Cell Function ◽

Elective Surgery ◽

High Mobility ◽

Underlying Mechanism ◽

Clinical Scenarios ◽

Stem And Progenitor Cells

A major discovery of recent decades has been the existence of stem cells and their potential to repair many, if not most, tissues. With the aging population, many attempts have been made to use exogenous stem cells to promote tissue repair, so far with limited success. An alternative approach, which may be more effective and far less costly, is to promote tissue regeneration by targeting endogenous stem cells. However, ways of enhancing endogenous stem cell function remain poorly defined. Injury leads to the release of danger signals which are known to modulate the immune response, but their role in stem cell-mediated repair in vivo remains to be clarified. Here we show that high mobility group box 1 (HMGB1) is released following fracture in both humans and mice, forms a heterocomplex with CXCL12, and acts via CXCR4 to accelerate skeletal, hematopoietic, and muscle regeneration in vivo. Pretreatment with HMGB1 2 wk before injury also accelerated tissue regeneration, indicating an acquired proregenerative signature. HMGB1 led to sustained increase in cell cycling in vivo, and using Hmgb1−/− mice we identified the underlying mechanism as the transition of multiple quiescent stem cells from G0 to GAlert. HMGB1 also transitions human stem and progenitor cells to GAlert. Therefore, exogenous HMGB1 may benefit patients in many clinical scenarios, including trauma, chemotherapy, and elective surgery.

Download Full-text

Adipose mesenchymal stem cell transplantation alleviates spinal cord injury-induced neuroinflammation partly by suppressing the Jagged1/Notch pathway

10.21203/rs.2.17540/v1 ◽

2019 ◽

Author(s):

Zhou Zhilai ◽

Tian Xiaobo ◽

Mo Biling ◽

Xu Huali ◽

Yao Shun ◽

...

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

Stem Cell ◽

Mesenchymal Stem Cell ◽

Notch Signaling ◽

Signaling Pathway ◽

Notch Signaling Pathway ◽

Therapeutic Effects ◽

Mesenchymal Stem Cell Transplantation ◽

Cord Injury

Abstract Background The therapeutic effects of adipose-derived mesenchymal stem cell (ADSC) transplantation have been demonstrated in several models of central nervous system (CNS) injury and are thought to involve the modulation of the inflammatory response. However, the exact underlying molecular mechanism is poorly understood. Activation of the Jagged1/Notch signaling pathway is thought to involve inflammatory and gliotic events in the CNS. Here, we elucidated the effect of ADSC transplantation on the inflammatory reaction after spinal cord injury (SCI) and the potential mechanism mediated by Jagged1/Notch signaling pathway suppression.Methods Using a mouse model of compression SCI, ADSCs and Jagged1 small interfering RNA (siRNA) were injected into the spinal cord. Locomotor function, spinal cord tissue morphology and the levels of various proteins and transcripts were compared between groups.Results ADSC treatment resulted in significant downregulation of proinflammatory mediator expression and reduced ionized calcium binding adapter molecule 1 (Iba1) and ED1 staining in the injured spinal cord, promoting the survival of neurons. These changes were accompanied by improved functional recovery. The augmentation of the Jagged1/Notch signaling pathway after SCI was suppressed by ADSC transplantation. The inhibition of the Jagged1/Notch signaling pathway by Jagged1 siRNA resulted in a decrease in SCI-induced proinflammatory cytokines as well as the activation of microglia. Furthermore, Jagged1 knockdown suppressed the phosphorylation of JAK/STAT3 following SCI.Conclusion The results of this study demonstrated that the therapeutic effects of ADSCs in SCI mice were partly due to Jagged1/notch signaling pathway inhibition and a subsequent reduction in JAK/STAT3 phosphorylation.

Download Full-text

Exosome derived from mesenchymal stem cells enhance autophagy and inhibit iNOS/TXNIP/NLRP3 inflammasome axis in injured spinal cord

10.21203/rs.3.rs-16805/v1 ◽

2020 ◽

Author(s):

Bin Lv ◽

Lei Wang ◽

Anquan Huang ◽

Tianming Zou ◽

Jishan Yuan

Keyword(s):

Nitric Oxide ◽

Spinal Cord ◽

Nlrp3 Inflammasome ◽

Neuroprotective Effect ◽

Neuronal Cells ◽

Tissue Loss ◽

Protective Effects ◽

Sprague Dawley ◽

Cord Injury

Abstract Background: Neuroinflammation, autophagy, NLRP3 inflammasome, and microglia polarizationhave been implicated in spinal cord injury (SCI).Moreover, exosomes, a classic nanovesicles secreted by MSCs, may have a neuroprotective effect on transformation of microglia from the M1 state to the M2 phenotype. However, the effect of MSCs derived exosomes on neuroinflammation is still unclear. Here, we investigated the mechanisms of MSCs derived exosomes mediated NLRP3 inflammasome signaling cascades and its protective effects in SCI. Methods:The SCI model was performed by weight-drop impact in adult male Sprague-Dawley (SD) rats. Control andexosome rats were randomly subjecttoexosomeadminister (20 mg/kg) or placebo via intraperitoneal route 1 h after SCI.Autophagy inhibitor(3-MA) was administered intraperitoneally 20 min before experiment.Neurological function was measured by Basso-Beattie-Bresnahan (BBB) scoring and an open-field test.Neuronal death was measured by HE stainingandNisslstaining.Inducible nitric oxide synthase (iNOS) levels were determined using fluorescent probes. The autophagy and TXNIP and its downstream signaling pathways-mediated polarization of macrophages/microglia was assessed by immunohistochemistry. Results:Exosome significantly downregulated intracellular iNOS and inhibited TXNIP, pyrin domain-containing 3 (NLRP3) inflammasome pathway activation by activating autophagy. Additionally, Exosomepromoted expression of autophagy markers, such as LC3A/B and beclin1,and abrogated the expression of p62. Autophagy inhibitor, 3-MA, blockage of autophagy flux abolished the inhibition of apoptosis and iNOS/TXNIP/NLRP3 inflammasome axisafterSCI. Here, we demonstrated that exosomeadministration in spinal cord markedly reduced tissue loss, attenuate pathological morphology of the injuredregion, and promoted tissue recovery. Moreover. our resultshowed that exosome administration alleviated neuronal cells apoptosis, and inhibited nitric oxide release in microglia.The activation of inflammatoryresponse in neuronal cells facilitates interactions of iNOS‐NLRP3 andTXNIP‐NLRP3and inhibited NLRP3 inflammasome where neuronal cells apoptosis was induced.Further, we found that exosome could suppress macrophages/microglia polarized to M1 phenotype in vivo and in vitro.Taken together, exosome administration exerts protective effects in neuronal cells through inhibiting iNOS production, and exosome administration could inhibit iNOS/TXNIP/NLRP3 inflammasome axis via enhancing autophagy and both in vitro and in vivo. Conclusions:These resultsreveal that exosometreatment alleviatedneuroinflammation and mitigates neuronal apoptosis via autophagy-mediate inhibition of the iNOS/TXNIP/NLRP3 inflammasome axis. Our findings suggest that exosome may be a novel therapeutic target for treating SCI.

Download Full-text