Stem Cells Translational Medicine最新文献

Retinal pigment epithelium (RPE) atrophy is a significant cause of human blindness worldwide, occurring in polygenic diseases such as age-related macular degeneration (AMD) and monogenic diseases such as Stargardt diseases (STGD1) and late-onset retinal degeneration (L-ORD). The patient-induced pluripotent stem cells (iPSCs)-derived RPE (iRPE) model exhibits many advantages in understanding the cellular basis of pathological mechanisms of RPE atrophy. The iRPE model is based on iPSC-derived functionally mature and polarized RPE cells that reproduce several features of native RPE cells, such as phagocytosis of photoreceptor outer segments (POS) and replenishment of visual pigment. When derived from patients, iRPE are able to recapitulate critical cellular phenotypes of retinal degenerative diseases, such as the drusen-like sub-RPE deposits in the L-ORD and AMD models; lipid droplets and cholesterol accumulation in the STGD1 and AMD models. The iRPE model has helped discover the unexpected role of RPE in understanding retinal degenerative diseases, such as a cell-autonomous function of ABCA4 in STGD1. The iRPE model has helped uncover the pathological mechanism of retinal degenerative diseases, including the roles of alternate complement cascades and oxidative stress in AMD pathophysiology, abnormal POS processing in STGD1 and L-ORD, and its association with lipid accumulation. These studies have helped better understand-the role of RPE in retinal degenerative diseases, and molecular mechanisms underlying RPE atrophy, and have provided a basis to discover therapeutics to target RPE-associated diseases.

We previously have shown the potential of human endomyocardial biopsy (EMB)-derived cardiac adherent proliferating cells (CardAPs) as a new cell-therapeutic treatment option for virus-induced myocarditis. To overcome the limited cell yield per EMB, CardAPs have been isolated from the human right atrial appendage (RAA) in view of allogeneic application and off-the-shelf use. We aimed to investigate the cardioprotective and immunomodulatory potential of RAA-CardAPs in experimental acute and chronic Coxsackievirus B3 (CVB3)-induced myocarditis upon injection in the viral and inflammatory phase. In the acute model, male C57BL6/J mice were intraperitoneally (i.p.) injected with the CVB3 Nancy strain or phosphate buffered saline (PBS). One day after infection, mice were intravenously (i.v.) injected with RAA-CardAPs, EMB-CardAPs (as reference cells) or PBS. For the chronic model, male Naval Medical Research Institute mice were i.p. injected with the CVB3 31-1-93 strain or PBS. Ten days after infection, mice were i.v. injected with RAA-CardAPs. Cardiac function was characterized, followed by harvest of the left ventricle (LV) and spleen for subsequent analysis, 7 and 28 days after CVB3 infection in the acute and chronic model, respectively. In the acute model, RAA-CardAPs decreased cardiac fibrosis and improved cardiac function in CVB3 mice. RAA-CardAPs mice exerted immunomodulatory effects as evidenced by lower LV chemokines expression (C-C motif ligand [CCL]2 and CCL7), CD68+ cells presence, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, tumor necrosis factor-α, and IL-6 mRNA expression. In the chronic model, RAA-CardAPs reduced cardiac fibrosis and the severity of myocarditis, associated with an improvement in LV function. We conclude that RAA-CardAPs represent a treatment strategy to reduce the development of acute and chronic CVB3-induced myocarditis.

Introduction: Pathogenic variants in canonical transforming growth factor β (TGFβ) signaling genes predispose patients to thoracic aortic aneurysm and dissection (TAAD), predominantly in aortic root. Although TAAD pathogenesis associated with TGFβ receptor defects is well characterized, distinct and redundant mechanisms of TGFβ isoforms in TAAD incidence and severity remain elusive.

Objective: Here we examined the biological role of TGFB2 in smooth muscle cell (SMC) differentiation and investigated how TGFB2 defects can lead to regional TAAD manifestations.

Methods: To characterize the role of TGFB2 in SMC differentiation and function, we employed human-induced pluripotent stem cell (hiPSC)-derived SMC differentiation, CRISPR/Cas9 gene editing, three-dimensional SMC constructs, and human aortic tissue samples.

Results: Despite the similar effects of different TGFβ isoforms on hiPSC-derived SMC differentiation, siRNA experiments revealed that TGFB2 distinctively displays TGFBR3 dependence for signal transduction, an understudied TGFβ receptor in TAAD. Molecular evaluation of different thoracic aorta regions suggested TGFB2 and TGFBR3 enrichment in the aortic root tunica media. TGFB2 haploinsufficiency (TGFB2KO/+) and TGFB2 neutralization impaired the differentiation of second heart field-derived SMCs. TGFBR3KO/KO prevented the molecular rescue of TGFB2KO/+ by TGFB2 supplementation indicating the involvement of TGFBR3 in TGFB2-mediated SMC differentiation. Lastly, a missense TGFB2 variant (TGFB2G276R/+) caused mechanical defects in SMC tissue ring constructs that were rescued by TGFB2 supplementation or genetic correction.

Conclusion: Our data suggests the distinct regulation and action of TGFB2 in SMCs populating the aortic root, while redundant activities of TGFβ isoforms provide implications about the milder TAAD aggressiveness of pathogenic TGFB2 variants.

Background: Bladder dysfunction may occur with high frequency in postmenopausal women with metabolic syndrome (MetS). This study evaluated the therapeutic effects of human amniotic fluid stem cells (hAFSCs) on bladder dysfunction in ovariectomized rats with MetS.

Materials and methods: Forty-eight female rats were divided into 4 groups: normal control, ovariectomy (OVX), and OVX and MetS without (OVX + MetS) and with hAFSCs treatment (OVX + MetS + hAFSCs). We assessed cystometric parameters, serum biochemistry parameters, wall thickness of iliac artery, apoptotic cells and collagen volume in bladder tissues, and the expressions of purinergic and muscarinic receptors, apoptosis-associated mitochondrial proteins, and markers of inflammation, fibrosis, and oxidative stress at posttreatment 1 and 3 months.

Results: OVX + MetS rats showed significant dysfunction of bladder storage, including reduced intercontraction intervals and bladder capacity, along with increased residual urine volume and nonvoiding contractions. There was a significant increase in iliac artery wall thickness, bladder collagen volume, and number of apoptotic cells. Also, there were elevated expressions of P2X3 purinergic and M2/M3 muscarinic receptors, pro-apoptotic proteins, and markers of inflammation, fibrosis, and oxidative stress, with a concurrent decrease in anti-apoptotic protein, Bcl-2. Treatment with hAFSCs helped restoring bladder function, ameliorating histological abnormalities, and reducing pathological markers at 1 and/or 3 months.

Conclusion: These findings suggest that hAFSCs can effectively mitigate bladder dysfunction in rats with ovarian hormone deficiency and MetS by modulating oxidative stress and mitochondrial apoptotic pathways.

The rapidly developing field of renal spheroids and organoids has emerged as a valuable tool for modeling nephrotoxicity, kidney disorders, and kidney development. However, existing studies have relied on intricate and sophisticated differentiation protocols to generate organoids and tubuloids, necessitating the external administration of multiple growth factors within precise timeframes. In our study, we demonstrated that human adult renal progenitor cells (ARPCs) isolated from the urine of both healthy subjects and patients can form spheroids that naturally generated very long tubule-like structures. Importantly, the generation of these tubule-like structures is driven solely by ARPCs, without the need for the external use of chemokines or growth factors to artificially induce this process. These tubule-like structures exhibit the expression of structural and functional renal tubule markers and bear, in some cases, striking structural similarities to various nephron regions, including the distal convoluted tubule, the loop of Henle, and proximal convoluted tubules. Furthermore, ARPC spheroids express markers typical of pluripotent cells, such as stage-specific embryonic antigen 4 (SSEA4), secrete elevated levels of renin, and exhibit angiogenic properties. Notably, ARPCs isolated from the urine of patients with IgA nephropathy form spheroids capable of recapitulating the characteristic IgA1 deposition observed in this disease. These findings represent significant advancements in the field, opening up new avenues for regenerative medicine in the study of kidney development, mechanisms underlying renal disorders, and the development of regenerative therapies for kidney-related ailments.

Many electronic cigarettes (ECs) contain high concentrations of menthol. The effect of menthol on human embryos in pregnant women who vape is not well understood. Human embryonic stem cells (hESCs) (an epiblast model) were used to test the hypothesis that 6.4-640 nM and 19.2-192 µM menthol, which activates TRP (transient-receptor-potential) channels, alters calcium homeostasis in embryos and adversely affects processes that are critical to gastrulation. Micromolar concentrations of menthol inhibited mitochondrial reductase activity in hESCs, an effect that was blocked by TRPA1 and TRPM8 inhibitors. Pulsatile exposure to menthol elevated intracellular calcium primarily by activating TRPA1 channels at nanomolar concentrations and TRPM8 channels at µM concentrations. nM menthol significantly inhibited colony growth by activating TRPA1 channels, while both TRPA1 and TRPM8 were activated by µM menthol. Inhibition of colony growth was attributed to cell death induced by menthol activation of TRPA1 and TRPM8 channels. nM menthol altered colony phenotype by increasing the major/minor axis ratio via TRPA1 and TRPM8 channels. Both nM and µM menthol induced alterations in hESC colony motility, an effect that was blocked only by the TRPM8 inhibitor. The menthol-induced increase in intracellular calcium adversely influenced growth, death, and migration, processes that are critical in gastrulation. Menthol concentrations that reach embryos in women who vape are high enough to activate TRPA1 and TRPM8 channels and perturbed calcium homeostasis. Pregnant women who vape likely expose their embryos to menthol concentrations that are harmful. These data could help prevent birth defects or embryo/fetal death.

The still young and developing space age, characterized by lunar and Martian exploration and the vision of extraterrestrial settlements, presents a unique environment to study the impact of microgravity (µg) on human physiology and disease development. Cancer research is currently a key focus of international space science, as µg fundamentally impacts cellular processes like differentiation, adhesion, migration, proliferation, survival, cell death, or growth of cancer cells as well as the cytoskeleton and the extracellular matrix (ECM). By creating three-dimensional (3D) tumor models in a µg-environment, like multicellular spheroids (MCS), researchers can expedite drug discovery and development, reducing the need for animal testing. This concise review analyses the latest knowledge on the influence of µg on cancer cells and MCS formation. We will focus on cells from brain tumors, lung, breast, thyroid, prostate, gastrointestinal, and skin cancer exposed to real (r-) and simulated (s-) µg-conditions.

Mesenchymal stromal/stem cells (MSCs) are promising candidates for regenerative medicine owing to their self-renewal properties, multilineage differentiation, immunomodulatory effects, and angiogenic potential. MSC spheroids fabricated by 3D culture have recently shown enhanced therapeutic potential. MSC spheroids create a specialized niche with tight cell-cell and cell-extracellular matrix interactions, optimizing their cellular function by mimicking the in vivo environment. Methods for 3D cultivation of MSCs can be classified into 2 main forms: static suspension culture and dynamic suspension culture. Numerous studies have reported the beneficial influence of these methods on MSCs, which is displayed by increased differentiation, angiogenic, immunomodulatory, and anti-apoptotic effects, and stemness of MSC spheroids. Particularly, recent studies highlighted the benefits of dynamic suspension cultures of the MSC spheroids in terms of faster and more compact spheroid formation and the long-term maintenance of stemness properties. However, only a few studies have compared the behavior of MSC spheroids formed using static and dynamic suspension cultures, considering the significant differences between their culture conditions. This review summarizes the differences between static and dynamic suspension culture methods and discusses the biological outcomes of MSC spheroids reported in the literature. In particular, we highlight the advantages of the dynamic suspension culture of MSC spheroids and contemplate its future applications for various diseases.

Extracellular vesicles (EVs) are evolutionarily conserved communication mediators that play key roles in the development of periodontal disease as well as in regeneration processes. This concise review first outlines the pathogenic mechanisms through which EVs derived from bacteria lead to the progression of periodontitis, with a focus on the enrichment of virulence factors, the amplification of immune responses, and the induction of bone destruction as key aspects influenced by bacterial EVs. This review aims to elucidate the positive effects of EVs derived from mesenchymal stem cells (MSC-EVs) on periodontal tissue regeneration. In particular, the anti-inflammatory properties of MSC-EVs and their impact on the intricate interplay between MSCs and various immune cells, including macrophages, dendritic cells, and T cells, are described. Moreover, recent advancements regarding the repair-promoting functions of MSC-EVs are detailed, highlighting the mechanisms underlying their ability to promote osteogenesis, cementogenesis, angiogenesis, and the homing of stem cells, thus contributing significantly to periodontal tissue regeneration. Furthermore, this review provides insights into the therapeutic efficacy of MSC-EVs in treating periodontitis within a clinical context. By summarizing the current knowledge, this review aims to provide a comprehensive understanding of how MSC-EVs can be harnessed for the treatment of periodontal diseases. Finally, a discussion is presented on the challenges that lie ahead and the potential practical implications for translating EV-based therapies into clinical practices for the treatment of periodontitis.

Regenerative therapies are currently lacking for spinal cord injury (SCI). Neural progenitor cells (NPCs) have emerged as a promising therapeutic approach. To facilitate translation of NPCs into the clinic, studying human NPCs in rodent models is required. The preclinical study of human NPCs in rodent models of SCI necessitates an optimal selection of immunomodulatory strategies, requiring a balance between modulating the immune system and preserving its functionality.