Wenshen Xiaozheng Tang alleviates fibrosis in endometriosis by regulating differentiation and paracrine signaling of endometrium-derived mesenchymal stem cells.

ETHNOPHARMACOLOGICAL RELEVANCE: Wenshen Xiaozheng Tang (WXT), a traditional Chinese medicine (TCM) decoction, is effective for treating endometriosis. However, the effect of WXT on endometrium-derived mesenchymal stem cells (eMSCs) which play a key role in the fibrogenesis of endometriosis requires further elucidation. AIMS OF THE STUDY: The aim of this study was to clarify the potential mechanism of WXT in improving fibrosis in endometriosis by investigating the regulation of WXT on differentiation and paracrine of eMSCs. MATERIALS AND METHODS: The nude mice with endometriosis were randomly divided into model group, WXT group and mifepristone group. After 21 days of treatment, the lesion volume was calculated. Fibrosis in the lesions was evaluated by Masson staining and expression of fibrotic proteins. The differentiation of eMSCs in vivo was explored using a fate-tracking experiment. To further clarify the regulation of WXT on eMSCs, primary eMSCs from the ectopic lesions of endometriosis patients were isolated and characterized. The effect of WXT on the proliferation and differentiation of ectopic eMSCs was examined. To evaluate the role of WXT on the paracrine activity of ectopic eMSCs, the conditioned medium (CM) from ectopic eMSCs pretreated with WXT was collected and applied to treat ectopic endometrial stromal cells (ESCs), after which the expression of fibrotic proteins in ectopic ESCs was assessed. In addition, transcriptome sequencing was used to investigate the regulatory mechanism of WXT on ectopic eMSCs, and western blot and ELISA were employed to determine the key mediator. RESULTS: WXT impeded the growth of ectopic lesions in nude mice with endometriosis and reduced collagen deposition and the expression of fibrotic proteins fibronectin, collagen I, α-SMA and CTGF in the endometriotic lesions. The fate-tracking experiment showed that WXT prevented human eMSCs from differentiating into myofibroblasts in the nude mice. We successfully isolated eMSCs from the lesions of patients with endometriosis and demonstrated that WXT suppressed proliferation and myofibroblast differentiation of ectopic eMSCs. Moreover, the expression of α-SMA, collagen I, fibronectin and CTGF in ectopic ESCs was significantly down-regulated by the CM of ectopic MSCs pretreated with WXT. Combining the results of RNA sequencing, western blot and ELISA, we found that WXT not only reduced thrombospondin 4 expression in ectopic eMSCs, but also decreased thrombospondin 4 secretion from ectopic eMSCs. Thrombospondin 4 concentration-dependently upregulated the expression of collagen I, fibronectin, α-SMA and CTGF in ectopic ESCs, indicating that thrombospondin 4 was a key mediator of WXT in inhibiting the fibrotic process in endometriosis. CONCLUSION: WXT improved fibrosis in endometriosis by regulating differentiation and paracrine signaling of eMSCs. Thrombospondin 4, whose release from ectopic eMSCs is inhibited by WXT, may be a potential target for the treatment of endometriosis.

Progression of mesenchymal stem cell regulation on imbalanced microenvironment after spinal cord injury.

Spinal cord injury (SCI) results in significant neural damage and inhibition of axonal regeneration due to an imbalanced microenvironment. Extensive evidence supports the efficacy of mesenchymal stem cell (MSC) transplantation as a therapeutic approach for SCI. This review aims to present an overview of MSC regulation on the imbalanced microenvironment following SCI, specifically focusing on inflammation, neurotrophy and axonal regeneration. The application, limitations and future prospects of MSC transplantation are discussed as well. Generally, a comprehensive perspective is provided for the clinical translation of MSC transplantation for SCI.

Exosomal therapy is a luxury area for regenerative medicine.

Stem cell-based therapies have made significant advancements in tissue regeneration and medical engineering. However, there are limitations to cell transplantation therapy, such as immune rejection and limited cell viability. These limitations greatly impede the translation of stem cell-based tissue regeneration into clinical practice. In recent years, exosomes, which are packaged vesicles released from cells, have shown promising progress. Specifically, exosomes derived from stem cells have demonstrated remarkable therapeutic benefits. Exosomes are nanoscale extracellular vesicles that act as paracrine mediators. They transfer functional cargos, such as miRNA and mRNA molecules, peptides, proteins, cytokines, and lipids, from MSCs to recipient cells. By participating in intercellular communication events, exosomes contribute to the healing of injured or diseased tissues and organs. Studies have shown that the therapeutic effects of MSCs in various experimental paradigms can be solely attributed to their exosomes. Consequently, MSC-derived exosomes can be modified and utilized to develop a unique cell-free therapeutic approach for treating multiple diseases, including neurological, immunological, heart, and other diseases. This review is divided into several categories, including the current understanding of exosome biogenesis, isolation techniques, and their application as therapeutic tools.

1,25-dihydroxyvitamin-D3 distinctly impacts the paracrine and cell-to-cell contact interactions between hPDL-MSCs and CD4+ T lymphocytes.

Introduction: Human periodontal ligament-derived mesenchymal stromal cells (hPDL-MSCs) possess a strong ability to modulate the immune response, executed via cytokine-boosted paracrine and direct cell-to-cell contact mechanisms. This reciprocal interaction between immune cells and hPDL-MSCs is influenced by 1,25-dihydroxyvitamin-D3 (1,25(OH)2D3). In this study, the participation of different immunomodulatory mechanisms on the hPDL-MSCs-based effects of 1,25(OH)2D3 on CD4+ T lymphocytes will be elucidated using different co-culture models with various cytokine milieus. Material and methods: hPDL-MSCs and CD4+ T lymphocytes were co-cultured indirectly and directly with inserts (paracrine interaction only) or directly without inserts (paracrine and direct cell-to-cell contact interaction). They were stimulated with TNF-α or IL-1ß in the absence/presence of 1,25(OH)2D3. After five days of co-cultivation, the CD4+ T lymphocyte proliferation, viability, and cytokine secretion were analyzed. Additionally, the gene expression of soluble and membrane-bound immunomediators was determined in hPDL-MSCs. Results: In the indirect and direct co-culture model with inserts, 1,25(OH)2D3 decreased CD4+ T lymphocyte proliferation and viability. The direct co-culture model without inserts caused the opposite effect. 1,25(OH)2D3 mainly decreased the CD4+ T lymphocyte-associated secretion of cytokines via hPDL-MSCs. The degree of these inhibitions varied between the different co-culture setups. 1,25(OH)2D3 predominantly decreased the expression of the soluble and membrane-bound immunomediators in hPDL-MSCs to a different extent, depending on the co-culture models. The degree of all these effects depended on the absence and presence of exogenous TNF-α and IL-1ß. Conclusion: These data assume that 1,25(OH)2D3 differently affects CD4+ T lymphocytes via the paracrine and direct cell-to-cell contact mechanisms of hPDL-MSCs, showing anti- or pro-inflammatory effects depending on the co-culture model type. The local cytokine microenvironment seems to be involved in fine-tuning these effects. Future studies should consider this double-edged observation by executing different co-culture models in parallel.

LRG1 promotes metastatic colorectal cancer growth through HER3 signaling.

BACKGROUND AND AIMS: Therapy failure in patients with metastatic colorectal cancer (mCRC, ∼80% occur in the liver) remains an overarching challenge. Preclinical studies demonstrated that HER3 promotes CRC cell survival, but therapies blocking the neuregulin-induced canonical HER3 signaling have made little impact in the clinic. Recent studies suggest that the liver microenvironment promotes CRC growth by activating HER3 in a neuregulin-independent fashion, thus elucidation of these mechanisms may reveal new strategies for treating patients with mCRC. METHODS: Patient-derived primary liver endothelial cells (ECs) were used to interrogate EC-CRC crosstalk. We conducted proteomic analysis to identify EC-secreted factor(s) that triggers non-canonical HER3 activation in CRC, and determined the subsequent effects on mCRC using diverse murine mCRC models. In vitro studies with genetic and pharmacological interventions were used to map the non-canonical HER3 pathway. RESULTS: We demonstrated that EC-secreted leucine-rich alpha-2-glycoprotein 1 (LRG1) directly binds and activates HER3 and promotes CRC growth distinct from neuregulin, the canonical HER3 ligand. Blocking host-derived LRG1 by gene knockout or a neutralizing antibody impaired mCRC outgrowth in the liver and prolonged mouse survival. We identified protein synthesis activated by the PI3K-PDK1-RSK-eIF4B axis as the biologically relevant signaling cascade downstream of the LRG1-HER3 interaction, which was not blocked by conventional HER3-specific antibodies that failed in prior clinical trials. CONCLUSIONS: LRG1 is a novel HER3 ligand and mediates liver-mCRC crosstalk. The LRG1-HER3 signaling axis is distinct from canonical HER3 signaling and represents a new therapeutic opportunity to treat patients with mCRC, and potentially other types of liver metastases.

Neuroscience of cancer: Research progress and emerging of the field.

Cancer cells immediately expand and penetrate adjoining tissues, as opposed to metastasis, that is the spread of cancer cells through the circulatory or lymphatic systems to more distant places via the invasion process. We found that a lack of studies discussed tumor development with the nervous system, by the aspects of cancer-tissue invasion (biological) and chemical modulation of growth that cascades by releasing neural-related factors from the nerve endings via chemical substances known as neurotransmitters. In this review, we aimed to carefully demonstrate and describe the cancer invasion and interaction with the nervous system, as well as reveal the research progress and the emerging neuroscience of cancer. An initial set of 160 references underwent systematic review and summarization. Through a meticulous screening process, these data were refined, ultimately leading to the inclusion of 98 studies that adhered to predetermined criteria. The outcomes show that one formidable challenge in the realm of cancer lies in its intrinsic heterogeneity and remarkable capacity for rapid adaptation. Despite advancements in genomics and precision medicine, there is still a need to identify new molecular targets. Considering cancer within its molecular and cellular environment, including neural components, is crucial for addressing this challenge. In conclusion, this review provides good referential data for direct, indirect, biological, and chemical interaction for nerve tissue-tumor interaction, suggesting the establishment of new therapy techniques and mechanisms by controlling and modifying neuron networks that supply signals to tumors.

Paracrine Activation of STAT3 Drives GM-CSF Expression in Breast Carcinoma Cells, Generating a Symbiotic Signaling Network with Breast Carcinoma-Associated Fibroblasts.

This study evaluated the paracrine signaling between breast carcinoma-associated fibroblasts (CAFs) and breast cancer (BCa) cells. Resolving cell-cell communication in the BCa tumor microenvironment (TME) will aid the development of new therapeutics. Here, we utilized our patented TAME (tissue architecture and microenvironment engineering) 3D culture microphysiological system, which is a suitable pathomimetic avatar for the study of the BCa TME. We cultured in 3D BCa cells and CAFs either alone or together in cocultures and found that when cocultured, CAFs enhanced the invasive characteristics of tumor cells, as shown by increased proliferation and spread of tumor cells into the surrounding matrix. Secretome analysis from 3D cultures revealed a relatively high secretion of IL-6 by CAFs. A marked increase in the secretion of granulocyte macrophage-colony stimulating factor (GM-CSF) when carcinoma cells and CAFs were in coculture was also observed. We theorized that the CAF-secreted IL-6 functions in a paracrine manner to induce GM-CSF expression and secretion from carcinoma cells. This was confirmed by evaluating the activation of STAT3 and gene expression of GM-CSF in carcinoma cells exposed to CAF-conditioned media (CAF-CM). In addition, the treatment of CAFs with BCa cell-CM yielded a brief upregulation of GM-CSF followed by a marked decrease, indicating a tightly regulated control of GM-CSF in CAFs. Secretion of IL-6 from CAFs drives the activation of STAT3 in BCa cells, which in turn drives the expression and secretion of GM-CSF. As a result, CAFs exposed to BCa cell-secreted GM-CSF upregulate inflammation-associated genes such as IL-6, IL-6R and IL-8, thereby forming a positive feedback loop. We propose that the tight regulation of GM-CSF in CAFs may be a novel regulatory pathway to target for disrupting the CAF:BCa cell symbiotic relationship. These data provide yet another piece of the cell-cell communication network governing the BCa TME.

The Role of MALAT1 in Regulating the Proangiogenic Functions, Invasion, and Migration of Trophoblasts in Selective Fetal Growth Restriction.

Epigenetic regulation is an important entry point to study the pathogenesis of selective fetal growth restriction (sFGR), and an understanding of the role of long noncoding RNAs (lncRNAs) in sFGR is lacking. Our study aimed to investigate the potential role of a lncRNA, metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), in sFGR using molecular biology experiments and gain- or loss-of-function assays. We found that the levels of MALAT1, ERRγ, and HSD17B1 were downregulated and that of miR-424 was upregulated in the placental shares of the smaller twins. Moreover, angiogenesis was impaired in the placental share of the smaller fetus and MALAT1 could regulate the paracrine effects of trophoblasts on endothelium angiogenesis and proliferation by regulating miR-424. In trophoblasts, MALAT1 could competitively bind to miR-424 to regulate the expression of ERRγ and HSD17B1, thus regulating trophoblast invasion and migration. MALAT1 overexpression could decrease apoptosis and promote proliferation, alleviating cell damage induced by hypoxia. Taken together, the downregulation of MALAT1 can reduce the expression of ERRγ and HSD17B1 by competitively binding to miR-424, impairing the proangiogenic effect of trophoblasts, trophoblast invasion and migration, and the ability of trophoblasts to compensate for hypoxia, which may be involved in the pathogenesis of sFGR through various aspects.

Hypoxic Upregulation of IER2 Increases Paracrine GMFG Signaling of Endoplasmic Reticulum Stress-CAF to Promote Chordoma Progression via Targeting ITGB1.

Currently, the oncogenic mechanism of endoplasmic reticulum stress-CAF (ERS-CAF) subpopulation in chordoma remains unknown. Here, single-cell RNA sequencing, spatial transcriptomics, GeoMx Digital Spatial Profiler, data-independent acquisition proteomics, bulk RNA-seq, and multiplexed quantitative immunofluorescence are used to unveil the precise molecular mechanism of how ERS-CAF affected chordoma progression. Results show that hypoxic microenvironment reprograms CAFs into ERS-CAF subtype. Mechanistically, this occurrs via hypoxia-mediated transcriptional upregulation of IER2. Overexpression of IER2 in CAFs promotes chordoma progression, which can be impeded by IER2 knockdown or use of ERS inhibitors. IER2 also induces expression of ERS-CAF marker genes and results in production of a pro-tumorigenic paracrine GMFG signaling, which exert its biological function via directly binding to ITGB1 on tumor cells. ITGB1 inhibition attenuates tumor malignant progression, which can be partially reversed by exogenous GMFG intervention. Further analyses reveal a positive correlation between ITGB1high tumor cell counts and SPP1+ macrophage density, as well as the spatial proximity of these two cell types. Clinically, a significant correlation of high IER2/ITGB1 expression with tumor aggressive phenotype and poor patient survival is observed. Collectively, the findings suggest that ERS-CAF regulates SPP1+ macrophage to aggravate chordoma progression via the IER2/GMFG/ITGB1 axis, which may be targeted therapeutically in future.

Mechanical force regulates the paracrine functions of ADSCs to assist skin expansion in rats.

BACKGROUND: In the repair of massive tissue defects using expanded large skin flaps, the incidence of complications increases with the size of the expanded area. Currently, stem cell therapy has limitations to solve this problem. We hypothesized that conditioned medium of adipose-derived stem cells (ADSC-CM) collected following mechanical pretreatment can assist skin expansion. METHODS: Rat aortic endothelial cells and fibroblasts were cultured with ADSC-CM collected under 0%, 10%, 12%, and 15% stretching force. Ten-milliliter cylindrical soft tissue expanders were subcutaneously implanted into the backs of 36 Sprague-Dawley rats. The 0% and 10% stretch groups were injected with ADSC-CM collected under 0% and 10% stretching force, respectively, while the control group was not injected. After 3, 7, 14, and 30 days of expansion, expanded skin tissue was harvested for staining and qPCR analyses. RESULTS: Endothelial cells had the best lumen formation and highest migration rate, and fibroblasts secreted the most collagen upon culture with ADSC-CM collected under 10% stretching force. The skin expansion rate was significantly increased in the 10% stretch group. After 7 days of expansion, the number of blood vessels in the expanded area, expression of the angiogenesis-associated proteins vascular endothelial growth factor, basic fibroblast growth factor, and hepatocyte growth factor, and collagen deposition were significantly increased in the 10% stretch group. CONCLUSIONS: The optimal mechanical force upregulates specific paracrine proteins in ADSCs to increase angiogenesis and collagen secretion, and thereby promote skin regeneration and expansion. This study provides a new auxiliary method to expand large skin flaps.

Stromal KITL/SCF promotes pancreas tissue homeostasis and restrains tumor progression.

Components of normal tissue architecture serve as barriers to tumor progression. Inflammatory and wound-healing programs are requisite features of solid tumorigenesis, wherein alterations to immune and non-immune stromal elements enable loss of homeostasis during tumor evolution. The precise mechanisms by which normal stromal cell states limit tissue plasticity and tumorigenesis, and which are lost during tumor progression, remain largely unknown. Here we show that healthy pancreatic mesenchyme expresses the paracrine signaling molecule KITL, also known as stem cell factor, and identify loss of stromal KITL during tumorigenesis as tumor-promoting. Genetic inhibition of mesenchymal KITL in the contexts of homeostasis, injury, and cancer together indicate a role for KITL signaling in maintenance of pancreas tissue architecture, such that loss of the stromal KITL pool increased tumor growth and reduced survival of tumor-bearing mice. Together, these findings implicate loss of mesenchymal KITL as a mechanism for establishing a tumor-permissive microenvironment.

Immunoregulatory paracrine effect of mesenchymal stem cells and mechanism in the treatment of osteoarthritis.

Osteoarthritis (OA) is a degenerative joint disease caused by chronic inflammation that damages articular cartilage. At present, the treatment of OA includes drug therapy to relieve symptoms and joint replacement therapy for advanced OA. However, these palliatives cannot truly block the progression of the disease from the immunological pathogenesis of OA. In recent years, bone marrow mesenchymal stem cell (BMSC) transplantation has shown great potential in tissue engineering repair. In addition, many studies have shown that BMSC paracrine signals play an important role in the treatment of OA through immune regulation and suppressing inflammation. At present, the mechanism of inflammation-induced OA and the use of BMSC transplantation in joint repair have been reviewed, but the mechanism and significance of BMSC paracrine signals in the treatment of OA have not been fully reviewed. Therefore, this article focused on the latest research progress on the paracrine effects of BMSCs in the treatment of OA and the related mechanisms by which BMSCs secrete cytokines to inhibit the inflammatory response, regulate immune balance, and promote cell proliferation and differentiation. In addition, the application potential of BMSC-Exos as a new type of cell-free therapy for OA is described. This review aimed to provide systematic theoretical support for the clinical application of BMSC transplantation in the treatment of OA.

Paracrine signalling in breast cancer: Insights into the tumour endothelial phenotype.

Tumour endothelial cells (TECs) are genetically and phenotypically distinct from their normal, healthy counterparts and provide various pro-tumourigenic effects. This study aimed to investigate the impact of conditioned media (CM) from non-tumourigenic MCF-12A breast epithelial cells as well as from MCF-7 and MDA-MB-231 breast cancer cells on human umbilical vein endothelial cells (HUVECs). Significant increases in cell viability were observed across all breast CM groups compared to controls, with notable differences between the MCF-12A, MCF-7, and MDA-MB-231 groups. Despite increased viability, no significant differences in MCM2 expression, a marker of cell proliferation, were detected. Morphological changes in HUVECs, including elongation, lumen formation, and branching, were more pronounced in breast cancer CM groups, especially in the MDA-MB-231 CM group. qPCR and Western blot analyses showed increased expression of TEC markers such as MDR1, LOX, and TEM8 in HUVECs treated with MCF-12A CM. The MCF-7 CM group significantly enhanced HUVEC migratory activity compared to MCF-12A CM, as evidenced by a scratch assay. These findings underscore distinct angiogenic responses elicited by non-tumourigenic and tumourigenic breast epithelial cells, with tumourigenic cells inducing a hyperactivated angiogenic response. The study highlights the differential effects of breast cancer cell paracrine signalling on endothelial cells and suggests the need for further investigation into TEC markers' role in both physiological and tumour angiogenesis.

Stem cell therapies for neurological disorders: current progress, challenges, and future perspectives.

Stem cell-based therapies have emerged as a promising approach for treating various neurological disorders by harnessing the regenerative potential of stem cells to restore damaged neural tissue and circuitry. This comprehensive review provides an in-depth analysis of the current state of stem cell applications in primary neurological conditions, including Parkinson's disease (PD), Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), multiple sclerosis (MS), stroke, spinal cord injury (SCI), and other related disorders. The review begins with a detailed introduction to stem cell biology, discussing the types, sources, and mechanisms of action of stem cells in neurological therapies. It then critically examines the preclinical evidence from animal models and early human trials investigating the safety, feasibility, and efficacy of different stem cell types, such as embryonic stem cells (ESCs), mesenchymal stem cells (MSCs), neural stem cells (NSCs), and induced pluripotent stem cells (iPSCs). While ESCs have been studied extensively in preclinical models, clinical trials have primarily focused on adult stem cells such as MSCs and NSCs, as well as iPSCs and their derivatives. We critically assess the current state of research for each cell type, highlighting their potential applications and limitations in different neurological conditions. The review synthesizes key findings from recent, high-quality studies for each neurological condition, discussing cell manufacturing, delivery methods, and therapeutic outcomes. While the potential of stem cells to replace lost neurons and directly reconstruct neural circuits is highlighted, the review emphasizes the critical role of paracrine and immunomodulatory mechanisms in mediating the therapeutic effects of stem cells in most neurological disorders. The article also explores the challenges and limitations associated with translating stem cell therapies into clinical practice, including issues related to cell sourcing, scalability, safety, and regulatory considerations. Furthermore, it discusses future directions and opportunities for advancing stem cell-based treatments, such as gene editing, biomaterials, personalized iPSC-derived therapies, and novel delivery strategies. The review concludes by emphasizing the transformative potential of stem cell therapies in revolutionizing the treatment of neurological disorders while acknowledging the need for rigorous clinical trials, standardized protocols, and multidisciplinary collaboration to realize their full therapeutic promise.

FGF2 is secreted in extracellular vesicles from lung cells.

The 18-kDa isoform of basic fibroblast growth factor (bFGF/FGF2) lacks a conventional signal peptide sequence and is exported by a novel membrane-associated transport pathway. Extracellular vesicles (EVs) are increasingly recognized as mediators of intercellular communication in the lung, and our prior work demonstrates that EVs carry cargo that contributes to hyperoxic lung injury and are biomarkers for bronchopulmonary dysplasia. We used primary human bronchial epithelial (HBE), pulmonary artery endothelial (HPAE), and fibroblast (HNF) cells to determine whether FGF2 was secreted in EVs. EVs were isolated by ultracentrifugation from HBE, HPAE, and HNF exposed to either normoxia or hyperoxia, followed by nanoparticle tracking analysis and electron microscopy. Hyperoxia exposure increased the total EV number. All three cell types released FGF2-18kDa both directly into the extracellular environment (secretome), as well as in EVs. HBE released more FGF2-18kDa in EVs during hyperoxia, and these were internalized and localized to both nuclei and cytoplasm of recipient cells. By co-immunoprecipitation, we identified potential binding partners of FGF2-18kDa in the nuclei, including histone 1.2 (H1.2) binding protein, that may mediate downstream effects that do not involve FGF2 binding to cell surface receptors. FGF2-18kDa interaction with H1.2 binding protein may indicate a mechanism by which FGF2 secreted in EVs modulates cellular processes. FGF2 was also found to increase angiogenesis by Matrigel assay. Further studies are necessary to determine the biological relevance of FGF2 in EVs as modulators of lung injury and disease.NEW & NOTEWORTHY We found that multiple lung cell types release basic fibroblast growth factor (FGF2)-18kDa both directly into the extracellular environment (secretome), as well as in extracellular vesicles (EVs). Bronchial epithelial cells released more FGF2-18kDa in EVs during hyperoxia, which could be internalized rapidly by recipient cells. We also identified potential binding partners of FGF2-18kDa in nuclei that may mediate downstream effects that do not involve FGF2 binding to cell surface receptors. We also confirmed a potential angiogenic role for FGF2-18kDa.

Compact bone mesenchymal stem cells-derived paracrine mediators for cell-free therapy in sepsis.

Sepsis, a life-threatening condition resulting in multiple organ dysfunction, is characterized by a dysregulated immune response to infection. Current treatment options are limited, leading to unsatisfactory outcomes for septic patients. Here, we present a series of studies utilizing compact bone mesenchymal stem cells (CB-MSCs) and their derived paracrine mediators, especially exosome (CB-MSCs-Exo), to treat mice with cecal ligation and puncture-induced sepsis. Our results demonstrate that CB-MSCs treatment significantly improves the survival rate of septic mice by mitigating excessive inflammatory response and attenuating sepsis-induced organ injuries. Furthermore, CB-MSCs-conditioned medium, CB-MSCs secretome (CB-MSCs-Sec), and CB-MSCs-Exo exhibit potent anti-inflammatory effects in lipopolysaccharide (LPS)-stimulated murine macrophage (RAW264.7). Intriguingly, intravenous administration of CB-MSCs-Exo confers superior protection against inflammation and organ damage in septic mice compared to CB-MSCs in certain aspects. Using liquid chromatography-tandem mass spectrometry (LC-MS/MS) shotgun proteomic analysis, we identify a range of characterized proteins derived from the paracrine activity of CB-MSCs, involved in critical biological processes such as immunomodulation and apoptosis. Our findings highlight that the paracrine products of CB-MSCs could serve as a promising cell-free therapeutic agent for sepsis.

Mesenchymal Stromal Cells Nanovesicles Carry microRNA with Nephroprotective Proprieties Regardless of Aging.

Containing information molecules from their parent cells and inclining to fuse with targeted cells, bone marrow mesenchymal stromal cells-derived extracellular vesicles (MSCs- EV) are valuable in nanomedicine. BACKGROUND: The effects of aging on the paracrine mechanism and in the production and action of MSCs-EV and their cargos of miR-26a and siRNA-26a for the treatment of tubular renal cells under nephrotoxicity injury remain unelucidated. OBJECTIVE: The purpose of this study was to evaluate MSCs-EV of different ages and their ability to deliver the cargos of miR-26a and siRNA-26a to target renal tubular cells affected by nephrotoxicity injury. METHODS: In a model of gentamicin-induced nephrotoxicity, renal tubular cells treated with MSCs-EV expressing or not expressing microRNA-26a were analyzed. Western blotting was utilized to evaluate cell cycle markers, and MTT assay was utilized to evaluate auto-renovation capacity. RESULTS: Tubular cells under nephrotoxicity injury showed decreased proliferative capacity, but the treatment in the tubular renal cells under nephrotoxicity injury with MSCs-EV expressing microRNA-26a showed nephroprotective effects, regardless of EV age. While the treatment with EV-mediated siRNA-26a failed to preserve the nephroprotective effects equally, regardless of age. CONCLUSION: Mesenchymal stromal cell nanovesicles carry microRNA with nephroprotective proprieties regardless of aging.

Evolving Strategies for Extracellular Vesicles as Future Cardiac Therapeutics: From Macro- to Nano-Applications.

Cardiovascular disease represents the foremost cause of mortality and morbidity worldwide, with a steadily increasing incidence due to the growth of the ageing population. Cardiac dysfunction leading to heart failure may arise from acute myocardial infarction (MI) as well as inflammatory- and cancer-related chronic cardiomyopathy. Despite pharmacological progress, effective cardiac repair represents an unmet clinical need, with heart transplantation being the only option for end-stage heart failure. The functional profiling of the biological activity of extracellular vesicles (EVs) has recently attracted increasing interest in the field of translational research for cardiac regenerative medicine. The cardioprotective and cardioactive potential of human progenitor stem/cell-derived EVs has been reported in several preclinical studies, and EVs have been suggested as promising paracrine therapy candidates for future clinical translation. Nevertheless, some compelling aspects must be properly addressed, including optimizing delivery strategies to meet patient needs and enhancing targeting specificity to the cardiac tissue. Therefore, in this review, we will discuss the most relevant aspects of the therapeutic potential of EVs released by human progenitors for cardiovascular disease, with a specific focus on the strategies that have been recently implemented to improve myocardial targeting and administration routes.

Bioorthogonal non-canonical amino acid tagging to track transplanted human induced pluripotent stem cell-specific proteome.

BACKGROUND: Human induced pluripotent stem cells (hiPSCs) and their differentiated cell types have a great potential for tissue repair and regeneration. While the primary focus of using hiPSCs has historically been to regenerate damaged tissue, emerging studies have shown a more potent effect of hiPSC-derived paracrine factors on tissue regeneration. However, the precise contents of the transplanted hiPSC-derived cell secretome are ambiguous. This is mainly due to the lack of tools to distinguish cell-specific secretome from host-derived proteins in a complex tissue microenvironment in vivo. METHODS: In this study, we present the generation and characterization of a novel hiPSC line, L274G-hiPSC, expressing the murine mutant methionyl-tRNA synthetase, L274GMmMetRS, which can be used for tracking the cell specific proteome via biorthogonal non-canonical amino acid tagging (BONCAT). We assessed the trilineage differentiation potential of the L274G-hiPSCs in vitro and in vivo. Furthermore, we assessed the cell-specific proteome labelling in the L274G-hiPSC derived cardiomyocytes (L274G-hiPSC-CMs) in vitro following co-culture with wild type human umbilical vein derived endothelial cells and in vivo post transplantation in murine hearts. RESULTS: We demonstrated that the L274G-hiPSCs exhibit typical hiPSC characteristics and that we can efficiently track the cell-specific proteome in their differentiated progenies belonging to the three germ lineages, including L274G-hiPSC-CMs. Finally, we demonstrated cell-specific BONCAT in transplanted L274G-hiPSC-CMs. CONCLUSION: The novel L274G-hiPSC line can be used to study the cell-specific proteome of hiPSCs in vitro and in vivo, to delineate mechanisms underlying hiPSC-based cell therapies for a variety of regenerative medicine applications.

Alexander Friedenstein, Mesenchymal Stem Cells, Shifting Paradigms and Euphemisms.

Six decades ago, Friedenstein and coworkers published a series of seminal papers identifying a cell population in bone marrow with osteogenic potential, now referred to as mesenchymal stem cells (MSCs). This work was also instrumental in establishing the identity of hematopoietic stem cell and the identification of skeletal stem/progenitor cell (SSPC) populations in various skeletal compartments. In recognition of the centenary year of Friedenstein's birth, I review key aspects of his work and discuss the evolving concept of the MSC and its various euphemisms indorsed by changing paradigms in the field. I also discuss the recent emphasis on MSC stromal quality attributes and how emerging data demonstrating a mechanistic link between stromal and stem/progenitor functions bring renewed relevance to Friedenstein's contributions and much needed unity to the field.