Stem Cell Reviews and Reports最新文献

Background: T cells play a crucial role in the pathogenesis of systemic lupus erythematosus (SLE), with their functions regulated by various metabolic pathways. This study explores SLE pathogenesis and the therapeutic effects of human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) via metabolic reprogramming.

Methods: Clinical data and peripheral blood samples were collected from 15 SLE patients and matched healthy controls. CD4⁺ T cells were isolated and activated in vitro with anti-CD3/CD28. Following 72 h of co-culture with hUC-MSCs, CD4⁺ T cell viability was assessed using the CCK-8 assay. The oxygen consumption rate (OCR) and glycolytic proton efflux rate (glycoPER) were measured with a Seahorse analyzer. Cytokine levels were detected by multiplex assay, and transcriptome sequencing was performed. Western blotting analyzed glucose metabolism-related enzymes and signaling pathways in lupus model mice.

Results: Compared to healthy controls, activated CD4⁺ T cells from SLE patients exhibited significantly increased OCR and glycoPER levels (P < 0.05). Following 72 h of co-culture with hUC-MSCs, OCR, glycoPER, cell viability, and pro-inflammatory factors in SLE-CD4⁺ T cells decreased markedly (P < 0.01). Upregulation of 434 genes and downregulation of 172 genes was observed, particularly in the JAK-STAT and PI3K-Akt pathways. hUC-MSCs inhibited the expression of glucose metabolism-related enzymes and the JAK-STAT and PI3K-Akt signaling pathways in lupus model mice.

Conclusion: hUC-MSCs inhibited the proliferation and function of aberrant CD4⁺ T cells in SLE patients by modulating glycometabolism and the JAK-STAT and PI3K-Akt signaling pathways, providing new insights into the therapeutic mechanisms of MSCs based on metabolic reprogramming.

Background: Several studies have reported the effectiveness of stem cell-derived extracellular vesicles (SC-EVs) in disease treatment. However, the efficacy of SC-EVs for severe acute pancreatitis (SAP) remains uncertain. This systematic review aimed to analyze and evaluate the effect of SC-EVs in the treatment of SAP in animal models by summarizing data from published studies.

Methods: We searched Pubmed, Embase, and Web of Science databases to identify preclinical studies investigating the therapeutic effect of SC-EVs on SAP. The primary outcome was the histopathological scores of pancreatic tissues, including inflammation, edema, and necrosis. Other outcome measures included levels of amylase, IL-6, IL-10, and TNF-α. Eligible studies were selected based on the inclusion and exclusion criteria. SYRCLE checklist was adopted to assess the quality and bias risks of included studies. Mean differences and 95% confidence intervals were calculated using the inverse variance method with a random effects model. All statistical analyses were performed using RevMan 5.3 software.

Results: A total of 8 studies including 126 animals were included. The results of meta-analysis revealed that SC-EVs treatment significantly reduced pancreatic histopathologic scores (total score: MD = -5.17, 95% CI: -5.79, -4.55; inflammation score: MD = -1.44, 95% CI: -1.70, -1.19; edema score: MD = -1.42, 95% CI: -1.75, -1.09; necrosis score: MD = -1.42, 95% CI: -1.80, -1.04), inhibited pro-inflammatory factor release (IL-6: SMD = -3.20, 95% CI: -4.51, -1.88; TNF-α SMD = -5.18, 95% CI: -6.96, -3.40), and enhancing the release of anti-inflammatory factors (IL-10 SMD = 4.15, 95% CI: 2.49, 5.81). Further subgroup analyses displayed SC-EVs treatment obviously attenuated animal pancreatic pathologic injury in traumatic pancreatitis and drug-induced acute pancreatitis, and the effect of SC-EVs to inhibit TNF-α secretion in the drug-induced SAP model was correlated with the dose of SC-EVs injection.

Conclusions: This meta-analysis displayed that SC-EVs were correlated with SAP injury alleviation and pancreas function reservation. Research into the treatment of SAP with SC-EVs is still in its early stage, necessitating further comprehensive investigations in the future to elucidate the therapeutic mechanisms of SC-EVs and their potential application in SAP.

Wound healing, a physiological process, involves several different types of cells, from immune cells to non-immune cells, including mesenchymal stromal/stem cells (MSC), and their interactions. Immune cells including macrophages, neutrophils, dendritic cells (DC), innate lymphoid cells (ILC), natural killer (NK) cells, and B and T lymphocytes participate in wound healing by secreting various mediators and interacting with other cells. MSCs, as self-renewing, fast proliferating, and multipotent stromal/stem cells, are found in a wide variety of tissues and critically involved in different phases of wound healing by secreting various molecules that help to improve tissue healing and regeneration. In this review, first, we described the four main phases of wound healing, second, we reviewed the function of MSCs, MSC secretome and immune cells in improving the progress of wound repair (mainly focusing on skin wound healing), third, we explained the immune cells/MSCs interactions in the process of wound healing and regeneration, and finally, we introduce clinical applications of MSCs to improve the process of wound healing.

Progress of human brain in vitro models stands as a keystone in neurological and psychiatric research, addressing the limitations posed by species-specific differences in animal models. The generation of human neurons from induced pluripotent stem cells (iPSCs) using transcription factor reprogramming protocols has been shown to reduce heterogeneity and improve consistency across different stem cell lines. Despite notable advancements, the current protocols still exhibit several shortcomings. This study focuses on standardizing and optimizing the procedure for iPSC-derived glutamatergic neurons generation through the inducible overexpression of Neurogenin-2. Noteworthy refinements include stringent scrutiny of genomic rearrangements post-fibroblast reprogramming, selection of a homogeneously integrated NGN2-cassettes population, and the incorporation of an intermediate step during neuronal differentiation to store neuronal progenitors. The neural culture showed a high degree of neuronal maturation and consistency, as shown by single-cell and network electrophysiological recordings. These advancements aim to provide more reliable tools for disease modelling and drug screening in neurological disorders.

Evidence accumulated mitochondria, as the "powerplants of the cell," express several functional receptors for external ligands that modify their function and regulate cell biology. This review sheds new light on the role of these organelles in sensing external stimuli to facilitate energy production for cellular needs. This is possible because mitochondria express some receptors on their membranes that are responsible for their autonomous responses. This is not surprising given the widely accepted hypothesis that these intracellular organelles originated from prokaryotic ancestors that fused with eukaryotic cells during early evolution. It has been reported that mitochondria express functional estrogen, androgen, glucocorticoid, 5-hydroxytryptamine, melatonin, and cannabinoid receptors. What is intriguing is recent evidence showing that mitochondria could also be directly regulated by active mediators of intracellular complement (complosome) and intrinsic mediators of purinergic signaling. Accordingly, they express receptors for intracellular complement cleavage fragments (C5a and C3a) as well as for adenosine triphosphate (ATP), which, besides its crucial role in transferring energy in the cells, is also an important signaling molecule interacting with P2X7 receptor expressed not only on the cell surface but also on the mitochondria membrane. Based on this, intrinsic complosome and purinergic signaling mediators emerge as important cooperating regulators of reactive oxygen species (ROS) release from mitochondria and activators of intracellular pattern recognition receptor Nlrp3 inflammasome. This activation within the beneficial "hormetic zone response" regulates cell metabolism, proliferation, migration, and adaptation to the surrounding challenges of the microenvironment in a favorable way.

Background: Conventional post-stroke edema management strategies are limitedly successful as in multiple cases of hemorrhagic transformation is being reported. Clinically, acute-ischemic-stroke (AIS) intervention by endovascular mesenchymal stem cells (MSCs) have shown benefits by altering various signaling pathways. Our previous studies have reported that intra-arterial administration of 1*10⁵ MSCs (IA-MSCs) were beneficial in alleviating post-stroke edema by modulating PKCδ/MMP9/AQP4 axis and helpful in preserving the integrity of blood-brain-barrier (BBB). However, the role of mitochondrial dysfunction and ROS generation post-AIS cannot be overlooked in context to the alteration of the BBB integrity and edema formation through the activation of inflammatory pathways. The anti-inflammatory activity of IA-MSCs in stroke has been reported to be regulated by sirtuin-1 (SIRT-1). Hence, the relationship between SIRT-1 and AQP4 towards regulation of post-stroke edema needs to be further explored. Therefore, the present study deciphers the molecular events towards AQP4 upregulation, mitochondrial dysfunction and BBB disruption in context to the modulation of SIRT-1/PKCδ/NFκB loop by IA-MSCs administration.

Methods: Ovariectomized SD rats were subjected to focal ischemia. SIRT-1 activator, SIRT-1 inhibitor, NFkB inhibitor and IA-MSCs were administered at optimized dose. At 24 h of reperfusion, behavioral tests were performed, and brains were harvested following euthanasia for molecular studies.

Results: IA-MSCs downregulated AQP4, PKCδ and NFkB expression, and upregulated SIRT-1 expression. SIRT-1 upregulation renders mitochondrial protection via reduction of oxidative stress resulting in BBB protection.

Conclusion: IA-MSCs can modulate SIRT-1 mediated AQP4 expression via mitochondrial ROS reduction and modification of NFkB transcriptional regulation.

Background: The hypobaric hypoxic atmosphere can cause adverse reactions or sickness. The purpose of this study was to explore the preventive effect and mechanism of human umbilical cord mesenchymal stem cells (hUC-MSCs) on acute pathological injury in mice exposed to high-altitude.

Methods: We pretreated C57BL/6 mice with hUC-MSCs via the tail vein injection, and then the mice were subjected to hypobaric hypoxic conditions for five days. The effects of hUC-MSCs on the pathological injury of lung, heart, brain were assessed by biochemical analysis, histopathological testing, quantitative real-time polymerase chain reaction (qPCR), and western blot (WB). Further, transcriptome sequencing was used to screen for the potential therapeutic targets of hUC-MSCs in acute pathological injury, the identified signaling axis was characterized using Apoe^-/- mice, qPCR and WB.

Results: hUC-MSCs administration notably prevented and relieved gastrointestinal symptoms and inflammation of lung and heart, increased blood oxygen saturation and serum superoxide dismutase (SOD) level, decreased serum malondialdehyde (MDA) level, rescued lung tissue injury and myocardial mitochondrial disorder, elevated nissl bodies number in brain tissue and reduced the degree of pulmonary and cerebral edema. Furthermore, hUC-MSCs pretreatment reversed the down-regulated Apoe and up-regulated Pdgf-b and p-Erk1/2 in the lung of hypobaric hypoxic mice. Thus, hUC-MSCs protected against acute pathological injury caused by hypobaric hypoxic condition via the Apoe/Pdgf-b/p-Erk1/2 axis, and the identified pathway was confirmed by the negative results of Apoe^-/- mice.

Conclusion: hUC-MSCs possess the preventive effect on acute pathological injury caused by hypobaric hypoxia environment at high-altitude.

Reliable models of the blood-brain barrier (BBB), wherein brain microvascular endothelial cells (BMECs) play a key role in maintenance of barrier function, are essential tools for developing therapeutics and disease modeling. Recent studies explored generating BMEC-like cells from human pluripotent stem cells (hPSCs) by mimicking brain-microenvironment signals or genetic reprogramming. However, due to the lack of comprehensive transcriptional studies, the exact cellular identity of most of these cells remains poorly defined. In this study we aimed to identify the most likely master transcription factors (TFs) for inducing brain endothelial cell (EC) fate and assess the transcriptomic changes following their introduction into immature ECs. Therefore, we first generated PSC-derived immature ECs by transient overexpression of the TF, ETV2. Subsequently, by performing an extensive meta-analysis of transcriptome studies of brain and non-brain ECs, 12 candidate TFs were identified, which might fate immature ECs towards cells with brain EC features. Following combinatorial overexpression of these 12 TFs tagged with unique barcodes, single cell transcriptomics identified a subset of transduced cells that resembled mid-gestational human brain ECs. Assessment of the TF barcodes present in these cells revealed significant enrichment of the TFs ZIC3, TFAP2C, TFAP2A, and DLX2. These TFs might be useful to fate PSC-EC to BMEC-like cells, which could be incorporated in human in vitro BBB models.

Human-induced pluripotent stem cell (hiPSC) technology has been applied in pathogenesis studies, drug screening, tissue engineering, and stem cell therapy, and patient-specific hiPSC-derived cardiomyocytes (hiPSC-CMs) have shown promise in disease modeling, including diabetic cardiomyopathy. High glucose (HG) treatment induces lipotoxicity in hiPSC-CMs, as evidenced by changes in cell size, beating rate, calcium handling, and lipid accumulation. Empagliflozin, an SGLT2 inhibitor, effectively mitigates the hypertrophic changes, abnormal calcium handling, and contractility impairment induced by HG. Glucose concentration influences SGLT2 expression in cardiomyocytes, highlighting its potential role in diabetic cardiomyopathy. These findings support the potential utility of hiPSC-CMs in studying diabetic cardiomyopathy and the efficacy of empagliflozin in ameliorating HG-induced cardiomyocyte dysfunction. Such research may advance developments in precision medicine and therapeutic interventions for patients with diabetic cardiomyopathy.