Intravenously transplanted mesenchymal stromal cells: a new endocrine reservoir for cardioprotection

Therapeutic trends of priming mesenchymal stem cells: A bibliometric analysis

Mesenchymal stem cells (MSCs) have gained substantial attention in regenerative medicine due to their multilineage differentiation potential and immunomodulatory capabilities. MSCs have demonstrated therapeutic promise in numerous preclinical and clinical studies across a variety of diseases, including neurodegenerative disorders, cardiovascular diseases, and autoimmune conditions. Recently, priming MSCs has emerged as a novel strategy to enhance their therapeutic efficacy by preconditioning them for optimal survival and function in challenging in vivo environments. This study presented a comprehensive bibliometric analysis of research activity in the field of priming mesenchymal stem cells (MSCs) from 2003 to 2023. Utilizing a dataset of 585 documents, we explored research trends, leading authors and countries, productive journals, and frequently used keywords. We also explored priming strategies to augment the therapeutic efficacy of MSCs. Our findings show increasing research productivity with a peak in 2019, identified the United States as the leading contributor, and highlighted WANG JA as the most prolific author. The most published journal was Stem Cell Research & Therapy. Keyword analysis revealed core research areas emerging hotspots, while coword and cited sources visualizations elucidated the conceptual framework and key information sources. Further studies are crucial to advance the translation of primed MSCs from bench to bedside, potentially revolutionizing the landscape of regenerative medicine.

Mitochondria in Mesenchymal Stem Cells: Key to Fate Determination and Therapeutic Potential

Mesenchymal stem cells (MSCs) have become popular tool cells in the field of transformation and regenerative medicine due to their function of cell rescue and cell replacement. The dynamically changing mitochondria serve as an energy metabolism factory and signal transduction platform, adapting to different cell states and maintaining normal cell activities. Therefore, a clear understanding of the regulatory mechanism of mitochondria in MSCs is profit for more efficient clinical transformation of stem cells. This review highlights the cutting-edge knowledge regarding mitochondrial biology from the following aspects: mitochondrial morphological dynamics, energy metabolism and signal transduction. The manuscript mainly focuses on mitochondrial mechanistic insights in the whole life course of MSCs, as well as the potential roles played by mitochondria in MSCs treatment of transplantation, for seeking pivotal targets of stem cell fate regulation and stem cell therapy.

Extracellular vesicles derived from HuMSCs alleviate daunorubicin-induced cardiac microvascular injury via miR-186-5p/PARP9/STAT1 signal pathway

Introduction

It is essential to acknowledge that the cardiovascular toxicity associated with anthracycline drugs can be partially attributed to the damage inflicted on blood vessels and endothelial cells. Extracellular vesicles (EVs) derived from mesenchymal stem cells (MSCs) have the potential to repair cellular processes and promote tissue regeneration through the transfer of signaling molecules such as miRNAs. In the present study, we investigated the effects of MSC-EVs on daunorubicin (DNR)-damaged human cardiac microvascular endothelial cells (HCMEC) and developing blood vessels of Chicken Chorioallantoic Membrane (CAM) in vivo.

Materials and methods

We constructed in vitro and in vivo models of DNR-damaged endothelial cells and developing blood vessel. Scratch wound assays, EdU assays, tube formation assays, and SA-β-Gal staining were used to evaluate the effects of MSC-EVs on cell migration, proliferation, angiogenesis capacity and cell senescence. Blood vessel area was used to assess the effects of MSC-EVs on CAM vasculature. RT-qPCR was used to detect the mRNA expression levels of inflammatory molecules. RNA sequencing was employed to compare differential gene expression and downstream regulatory mechanisms. RNA interference experiments and miRNA mimic overexpression experiments were used to validate the regulatory effects of target genes and downstream signaling pathways.

Results

We found that MSC-EVs improved the migration, proliferation, and angiogenesis of HCMEC, while also alleviating cellular senescence. The angiogenic effect on the developing blood vessels was confirmed in vivo. We identified that MSC-EVs downregulated the expression of PARP9, thereby inhibiting the STAT1/pSTAT1 signaling pathway. This downregulation effect is likely mediated by the transfer of miR-186-5p from MSC-EVs to HCMEC. Overexpression of miR-186-5p in DNR-damaged HCMEC also exhibited the aforementioned downregulation effect. In vivo, the introduction of miR-186-5p mimics enhanced angiogenesis in the CAM model.

Conclusions

To summarize, our study reveals that MSC-EVs can restore the cellular function of DNR-damaged HCMEC and alleviate cellular senescence through the miR-185-5p-PARP9-STAT1/pSTAT1 pathway. This finding highlights the potential of MSC-EVs as a therapeutic strategy for mitigating the detrimental effects of anthracycline-induced endothelial damage.

Human PSC-derived cardiac cells and their products: therapies for cardiac repair

Despite the dramatic improvements in the management of patients with chronic heart failure which have occurred over the last decades, some of them still exhaust conventional drug-based therapies without being eligible for more aggressive options like heart transplantation or implantation of a left ventricular assist device. Cell therapy has thus emerged as a possible means of filling this niche. Multiple cell types have now been tested both in the laboratory but also in the clinics and it is fair to acknowledge that none of the clinical trials have yet conclusively proven the efficacy of cell-based approaches. These clinical studies, however, have entailed the use of cells from various sources but of non-cardiac lineage origins. Although this might not be the main reason for their failures, the discovery of pluripotent stem cells capable of generating cardiomyocytes now raises the hope that such cardiac-committed cells could be therapeutically more effective. In this review, we will first describe where we currently are with regard to the clinical trials using PSC-differentiated cells and discuss the main issues which remain to be addressed. In parallel, because the capacity of cells to stably engraft in the recipient heart has increasingly been questioned, it has been hypothesized that a major mechanism of action could be the cell-triggered release of biomolecules that foster host-associated reparative pathways. Thus, in the second part of this review, we will discuss the rationale, clinically relevant advantages and pitfalls associated with the use of these PSC "products".

A Review of Labeling Approaches Used in Small Extracellular Vesicles Tracing and Imaging

Small extracellular vesicles (sEVs), a subset of extracellular vesicles (EVs) originating from the endosomal compartment, are a kind of lipid bilayer vesicles released by almost all types of cells, serving as natural carriers of nucleic acids, proteins, and lipids for intercellular communication and transfer of bioactive molecules. The current findings suggest their vital role in physiological and pathological processes. Various sEVs labeling techniques have been developed for the more advanced study of the function, mode of action, bio-distribution, and related information of sEVs. In this review, we summarize the existing and emerging sEVs labeling techniques, including fluorescent labeling, radioisotope labeling, nanoparticle labeling, chemical contrast agents labeling, and label-free technique. These approaches will pave the way for an in-depth study of sEVs. We present a systematic and comprehensive review of the principles, advantages, disadvantages, and applications of these techniques, to help promote applications of these labeling approaches in future research on sEVs.

Targeted cell delivery of mesenchymal stem cell therapy for cardiovascular disease applications: a review of preclinical advancements

Cardiovascular diseases (CVD) continue to be the leading cause of morbidity and mortality globally and claim the lives of over 17 million people annually. Current management of CVD includes risk factor modification and preventative strategies including dietary and lifestyle changes, smoking cessation, medical management of hypertension and cholesterol lipid levels, and even surgical revascularization procedures if needed. Although these strategies have shown therapeutic efficacy in reducing major adverse cardiovascular events such as heart attack, stroke, symptoms of chronic limb-threatening ischemia (CLTI), and major limb amputation significant compliance by patients and caregivers is required and off-target effects from systemic medications can still result in organ dysfunction. Stem cell therapy holds major potential for CVD applications but is limited by the low quantities of cells that are able to traffic to and engraft at diseased tissue sites. New preclinical investigations have been undertaken to modify mesenchymal stem cells (MSCs) to achieve targeted cell delivery after systemic administration. Although previous reviews have focused broadly on the modification of MSCs for numerous local or intracoronary administration strategies, here we review recent preclinical advances related to overcoming challenges imposed by the high velocity and dynamic flow of the circulatory system to specifically deliver MSCs to ischemic cardiac and peripheral tissue sites. Many of these technologies can also be applied for the targeted delivery of other types of therapeutic cells for treating various diseases.

Therapeutic potential of extracellular vesicles derived from cardiac progenitor cells in rodent models of chemotherapy-induced cardiomyopathy

Background

Current treatments of chemotherapy-induced cardiomyopathy (CCM) are of limited efficacy. We assessed whether repeated intravenous injections of human extracellular vesicles from cardiac progenitor cells (EV-CPC) could represent a new therapeutic option and whether EV manufacturing according to a Good Manufacturing Practices (GMP)-compatible process did not impair their bioactivity.

Methods

Immuno-competent mice received intra-peritoneal injections (IP) of doxorubicin (DOX) (4 mg/kg each; cumulative dose: 12 mg/kg) and were then intravenously (IV) injected three times with EV-CPC (total dose: 30 billion). Cardiac function was assessed 9-11 weeks later by cardiac magnetic resonance imaging (CMR) using strain as the primary end point. Then, immuno-competent rats received 5 IP injections of DOX (3 mg/kg each; cumulative dose 15 mg/kg) followed by 3 equal IV injections of GMP-EV (total dose: 100 billion). Cardiac function was assessed by two dimensional-echocardiography.

Results

In the chronic mouse model of CCM, DOX + placebo-injected hearts incurred a significant decline in basal (global, epi- and endocardial) circumferential strain compared with sham DOX-untreated mice (p = 0.043, p = 0.042, p = 0.048 respectively) while EV-CPC preserved these indices. Global longitudinal strain followed a similar pattern. In the rat model, IV injections of GMP-EV also preserved left ventricular end-systolic and end-diastolic volumes compared with untreated controls.

Conclusions

Intravenously-injected extracellular vesicles derived from CPC have cardio-protective effects which may make them an attractive user-friendly option for the treatment of CCM.

Superior protective effects of PGE2 priming mesenchymal stem cells against LPS-induced acute lung injury (ALI) through macrophage immunomodulation

BACKGROUND

Mesenchymal stem cells (MSCs) have demonstrated remarkable therapeutic promise for acute lung injury (ALI) and its severe form, acute respiratory distress syndrome (ARDS). MSC secretomes contain various immunoregulatory mediators that modulate both innate and adaptive immune responses. Priming MSCs has been widely considered to boost their therapeutic efficacy for a variety of diseases. Prostaglandin E2 (PGE2) plays a vital role in physiological processes that mediate the regeneration of injured organs.

METHODS

This work utilized PGE2 to prime MSCs and investigated their therapeutic potential in ALI models. MSCs were obtained from human placental tissue. MSCs were transduced with firefly luciferase (Fluc)/eGFP fusion protein for real-time monitoring of MSC migration. Comprehensive genomic analyses explored the therapeutic effects and molecular mechanisms of PGE2-primed MSCs in LPS-induced ALI models.

RESULTS

Our results demonstrated that PGE2-MSCs effectively ameliorated lung injury and decreased total cell numbers, neutrophils, macrophages, and protein levels in bronchoalveolar lavage fluid (BALF). Meanwhile, treating ALI mice with PGE2-MSCs dramatically reduced histopathological changes and proinflammatory cytokines while increasing anti-inflammatory cytokines. Furthermore, our findings supported that PGE2 priming improved the therapeutic efficacy of MSCs through M2 macrophage polarization.

CONCLUSION

PGE2-MSC therapy significantly reduced the severity of LPS-induced ALI in mice by modulating macrophage polarization and cytokine production. This strategy boosts the therapeutic efficacy of MSCs in cell-based ALI therapy.

CSF2RB overexpression promotes the protective effects of mesenchymal stromal cells against ischemic heart injury

Aims: The invasive intramyocardial injection of mesenchymal stromal cells (MSCs) allows for limited repeat injections and shows poor therapeutic efficacy against ischemic heart failure. Intravenous injection is an alternative method because this route allows for repeated, noninvasive, and easy delivery. However, the lack of targeting of MSCs hinders the ability of these cells to accumulate in the ischemic area after intravenous injections. We investigated whether and how the overexpression of colony-stimulating factor 2 receptor beta subunit (CSF2RB) may regulate the cardiac homing of MSCs and their cardioprotective effects against ischemic heart failure. Methods and Results: Adult mice were subjected to myocardial ischemia/reperfusion (MI/R) or sham operations. We observed significantly higher CSF2 protein expression and secretion by the ischemic heart from 1 day to 2 weeks after MI/R. Mouse adipose tissue-derived MSCs (ADSCs) were infected with adenovirus harboring CSF2RB or control adenovirus. Enhanced green fluorescent protein (EGFP)-labeled ADSCs were intravenously injected into MI/R mice every three days for a total of 7 times. Compared with ADSCs infected with control adenovirus, intravenously delivered ADSCs overexpressing CSF2RB exhibited markedly increased cardiac homing. Histological analysis revealed that CSF2RB overexpression significantly enhanced the ADSC-mediated proangiogenic, antiapoptotic, and antifibrotic effects. More importantly, ADSCs overexpressing CSF2RB significantly increased the left ventricular ejection fraction and cardiac contractility/relaxation in MI/R mice. In vitro experiments demonstrated that CSF2RB overexpression increases the migratory capacity and reduces the hypoxia/reoxygenation-induced apoptosis of ADSCs. We identified STAT5 phosphorylation as the key mechanism underlying the effects of CSF2RB on promoting ADSC migration and inhibiting ADSC apoptosis. RNA sequencing followed by cause-effect analysis revealed that CSF2RB overexpression increases the expression of the ubiquitin ligase RNF4. Coimmunoprecipitation and coimmunostaining experiments showed that RNF4 binds to phosphorylated STAT5. RNF4 knockdown reduced STAT5 phosphorylation as well as the antiapoptotic and promigratory actions of ADSCs overexpressing CSF2RB. Conclusions: We demonstrate for the first time that CSF2RB overexpression optimizes the efficacy of intravenously delivered MSCs in the treatment of ischemic heart injury by increasing the response of the MSCs to a CSF2 gradient and CSF2RB-dependent STAT5/RNF4 activation.

Effects of Malate Ringer's solution on myocardial injury in sepsis and enforcement effects of TPP@PAMAM-MR

BACKGROUND

Myocardial dysfunction played a vital role in organ damage after sepsis. Fluid resuscitation was the essential treatment in which Lactate Ringer's solution (LR) was commonly used. Since LR easily led to hyperlactatemia, its resuscitation effect was limited. Malate Ringer's solution (MR) was a new resuscitation crystal liquid. Whether MR had a protective effect on myocardial injury in sepsis and the relevant mechanism need to be studied.

METHODS

The cecal ligation and puncture (CLP) inducing septic model and lipopolysaccharide (LPS) stimulating cardiomyocytes were used, and the cardiac function, the morphology and function of mitochondria were observed. The protective mechanism of MR on myocardial injury was explored by proteomics. Then the effects of TPP@PAMAM-MR, which consisted of the mitochondria- targeting polymer embodied malic acid, was further observed.

RESULTS

Compared with LR, MR resuscitation significantly prolonged survival time, improved the cardiac function, alleviated the damages of liver, kidney and lung following sepsis in rats. The proteomics of myocardial tissue showed that differently expressed proteins between MR and LR infusion involved oxidative phosphorylation, apoptosis. Further study found that MR decreased ROS, improved the mitochondrial morphology and function, and ultimately enhanced mitochondrial respiration and promoted ATP production. Moreover, MR infusion decreased the expression of apoptosis-related proteins and increased the expression of anti-apoptotic proteins. TPP@PAMAM@MA was a polymer formed by wrapping L-malic acid with poly amido amine (PAMAM) modified triphenylphosphine material. TPP@PAMAM-MR (TPP-MR), which was synthesized by replacing the L-malic acid of MR with TPP@PAMAM@MA, was more efficient in targeting myocardial mitochondria and was superior to MR in protecting the sepsis-inducing myocardial injury.

CONCLUSION

MR was suitable for protecting myocardial injury after sepsis. The mechanism was related to MR improving the function and morphology of cardiomyocyte mitochondria and inhibiting cardiomyocyte apoptosis. The protective effect of TPP-MR was superior to MR.