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Abstract Myocardial infarction (MI) is a leading cause of heart failure, disability and mortality worldwide. In this study, the effects of intramyocardial injection of human platelet lysate (HPL), bone marrow mesenchymal stem cells pretreated with HPL (PMSCs), and PMSC lysate (lys), alone and in combination were investigated on MI-induced by LAD ligation in male Wistar rats. The experiment was carried out on sham, vehicle (Veh), HPL, PMSCs, PMSC lysate (PMSC lys), HPL + PMSCs, and HPL + PMSC lys groups. SBP, DBP, and ± dp/dt max were monitored by the PowerLab physiograph. The MSC characteristics and CD31, NKX2.5, and cardiac troponin I (cTnI) contents were determined by flow cytometry, immunohistochemistry, and immunofluorescence, respectively. SBP, DBP, and ± dp/dt max that decreased in the MI group were recovered by HPL, PMSC, PMSC lys, HPL + PMSC, and HPL + PMSC lys treatments. CD31 density was higher in all treated groups compared to the Veh group. CD31 density in the HPL + PMSCs and HPL + PMSC lys groups was higher than in the PMSCs group. The number of Dil+/NKX2.5 + and Dil+/cTnI + cells was higher in the HPL + PMSCs group compared to the PMSCs group. The HPL and PMSCs mitigates heart injuries and cardiac dysfunction after MI. HPL provides an appropriate environment for cardiomyocyte differentiation from PMSCs.

Abstract Osteoarthritis (OA) is a chronic degenerative joint condition characterised by cartilage deterioration and changes in bone morphology, resulting in pain and impaired joint mobility. Investigation into the pathophysiological mechanisms underlying OA has highlighted the significance of mitochondrial dysfunction in its progression. Mitochondria, which are cellular organelles, play a crucial role in regulating energy metabolism, generating reactive oxygen species, and facilitating essential biological processes including apoptosis. In recent years, the utilisation of exogenous drugs and MT to improve mitochondrial function in chondrocytes has shown great promise in OA treatment. Numerous studies have investigated the potential of stem cells and extracellular vesicles in mitochondrial transfer. This review aims to explore the underlying mechanisms of mitochondrial dysfunction in OA and assess the progress in utilising mitochondrial transfer as a therapeutic approach for this disease.

Abstract Perianal fistulizing Crohn’s disease (CD) is a severe gastrointestinal disorder causing extensive mucosal damage with limited treatment options. Severe manifestations of the disease appear at higher rates in non-Europeans but the genetic and cellular mechanisms driving the disease phenotypes remain poorly understood. Herein, we tested whether pathologic determinants in the epithelial stem cell compartment could be detected at the transcript level in rectal organoids derived from a diverse patient population. Rectal organoid and mucosal cells from endoscopic biopsies of each patient having perianal fistulizing CD or no disease controls were prepared for and sequenced at the single cell level. After cell type annotations based on expressed marker genes, samples were analyzed by principal components, for differential transcript expression, cell type proportions, and pathway enrichment. After QC, we produced 77,044 rectal organoid cells (n = 13 patients; 8 CD, 5 controls) with high quality sequences that identified 10 distinct epithelial subtypes, that we compared to 141,367 mucosal epithelial cells (n = 29 patients; 18 CD, 11 controls). Consistent with mucosal epithelial cells, rectal organoids prominently displayed disease signatures represented by the stem and transit amplifying regions of the rectal crypt, including alterations in transcriptional signatures of metabolic, epigenetic, and proliferating pathways. Organoids also retained their gender- and ancestral-specific gene expression signatures. However, they lacked many of the inflammatory signatures observed in epithelial cells from diseased mucosa. Perianal CD patient derived rectal organoids reflect gene expression signatures related to disease, gender, and ancestry, suggesting they harbor inherent properties amenable to further patient-specific, disease-related experimentation.

Abstract Background Regulatory applications for cell therapy face more objections compared to conventional small molecule or biological drugs, leading to delays in market approval and clinical adoption. Increased regulatory objections frequently relate to issues regarding preclinical evidence, such as experimental design of animal studies, selection of animal models, endpoints, and determination of mechanism of action. Synthesis and clarification of the preclinical evidence necessary to demonstrate treatment efficacy and advance into early-phase clinical trials is needed to help researchers avoid regulatory objections. Methods We conducted a scoping review in which we searched repositories of the International Council for Harmonisation and all national member organizations (N = 38) for documents related to preclinical studies of cell therapies. Active guidance documents related to cell therapy were included, with no restrictions based on the year or language of publication. Data extraction was conducted in duplicate with conflicts resolved through consensus discussion. Results From 1215 identified documents, a total of 182 were included and analyzed, with 71% originating from ten major regulatory agencies. The most prevalent preclinical item addressed was the mechanism of action (n = 161, 88% of documents), underscoring its importance in bridging preclinical findings to clinical application. Most documents (n = 140, 77%) emphasized the importance of using clinically relevant preclinical models, though specific recommendations on models of disease were less common (n = 81, 45%). Selection of clinically relevant intervention parameters (n = 136, 75%) and outcome measures (n = 121, 66%) were also frequently recommended, but selection of relevant comparator groups appeared less frequently (n = 35, 19%). Furthermore, robust study design elements such as randomization and blinding were less frequently recommended, appearing in 31% of documents (n = 57). Comparison with clinical trial guidance revealed a significant gap in the rigor of study design recommendations for preclinical research. Conclusions Regulatory guidance for preclinical efficacy studies often recommends a strong emphasis on the clinical relevance of animal models, intervention parameters, outcomes, and mechanism of action. Incorporating these recommendations into early preclinical studies should improve the acceptability of preclinical evidence for approval by the relevant national regulators and can be used as a guide to ensure that all evidence that regulators say they expect is efficiently assembled into new clinical trial applications.

Background. The purpose of the present study was to investigate the effect of aerobic-resistance training on the population of cardiac multipotent cells, thickness, and diameter of the ventricular through the C-Kit pathway of male rats during the growth stages. Methods. Overall, 30 male Wistar rats in three age groups of 2 (n = 10), 8 (n = 10), and 96 (n = 10) weeks were accidentally divided into exercise and control groups. Resistance training programs (resistance ladder, 3 days a week) and aerobics (treadmill running, 3 days a week) were performed for 6 weeks. Hematoxylin-Eosin staining was done the heart tissue and histological images were prepared. Afterward, C-Kit gene expression was examined by the real-time polymerase chain reaction method. The statistical method of one-way analysis of variance (P ≥ 0.05) and Tukey’s test were used at a significant level (P ≥ 0.01). Results. The trained neonatal group had higher values in heart weight to body weight index, and the trained neonatal and trained young adult groups had higher values in left ventricular thickness (P ≥ 0.01). The decrease in left ventricular internal diameter in the trained young adult group was significant compared to the control group (P ≥ 0.01). There was a significant increase in C-Kit gene expression in trained young adult and trained old groups (P ≥ 0.01). Conclusion. Aerobic-resistance training can be an effective stimulus for increasing the number of cardiac stem cells and creating structural adaptations of the heart, including increasing thickness and ventricular diameter in neonatal and young adult groups. Practical Implications. Participation in aerobic-resistance training programs leads to the improvement of the cardiac structure and an increase in cardiac stem cells.

Intestinal stem cells are regulated by the intestinal nervous system, and both of them are closely related to intestinal inflammation. Relevant studies have shown the existence of intestinal nerve dysfunction in intestinal inflammation. By summarizing the relationship among intestinal stem cells, intestinal nervous system and intestinal inflammation, this paper discusses that intestinal nervous system injury related to intestinal inflammation may be the basis for persistent alteration of intestinal function, while enteric neurons provide feasible targets for improving intestinal nerve dysfunction in inflammatory bowel diseases, so as to apply various types of stem cells to the improvement of intestinal nerve dysfunction in intestinal inflammation.

Abstract In order to survive and replicate, Salmonella has evolved mechanisms to gain access to intestinal epithelial cells of the crypt. However, the impact of Salmonella Typhimurium on stem cells and progenitors, which are responsible for the ability of the intestinal epithelium to renew and protect itself, remains unclear. Given that intestinal organoids growth is sustained by stem cells and progenitors activity, we have used this model to document the effects of Salmonella Typhimurium infection on epithelial proliferation and differentiation, and compared it to an in vivo model of Salmonella infection in mice. Among gut segments, the caecum was preferentially targeted by Salmonella. Analysis of infected crypts and organoids demonstrated increased length and size, respectively. mRNA transcription profiles of infected crypts and organoids pointed to upregulated EGFR-dependent signals, associated with a decrease in secretory cell lineage differentiation. To conclude, we show that organoids are suited to mimic the impact of Salmonella on stem cells and progenitors cells, carrying a great potential to drastically reduce the use of animals for scientific studies on that topic. In both models, the EGFR pathway, crucial to stem cells and progenitors proliferation and differentiation, is dysregulated by Salmonella, suggesting that repeated infections might have consequences on crypt integrity and further oncogenesis.

The 24th and 19th International Congresses on Reproduction and Stem Cell Biology in the Islamic Republic of Iran broughttogether experts and researchers worldwide to explore the latest advancements in these fields. Different topics werediscussed, including such as reproductive health, infertility treatments, stem cell research, and regenerative medicine.This report provides a summary of the congress’s key findings by emphasizing pioneer research and technologies thatcan influence the future of reproduction and stem cell biology programs. The presence of keynote speakers such asProfessor Nicolas Rivron, Mohammad Ebrahim Parsanezhad, Ashraf Moini, Abbas Aflatoonian, Hadi Shafiee, AnnaBrini, Omid Camron Farokhzad, and Jeffrey Schweitzer added value to the event, which had over 1100 participantsfrom around the world. While foreign speakers were from various countries Iranian speakers mainly came from Tabriz,Isfahan, Shiraz, Babol, and Tehran that all discussed cutting-edge science and successful disease treatments. Toensure a more comprehensive representation, it is suggested that a wider geographic distribution of national andforeign speakers should be considered in future plan.

Abstract Our research endeavors are directed towards unraveling the stem cell characteristics of lower-grade glioma patients, with the ultimate goal of formulating personalized treatment strategies. We computed enrichment stemness scores and performed consensus clustering to categorize phenotypes. Subsequently, we constructed a prognostic risk model using weighted gene correlation network analysis (WGCNA), random survival forest regression analysis as well as full subset regression analysis. To validate the expression differences of key genes, we employed experimental methods such as quantitative Polymerase Chain Reaction (qPCR) and assessed cell line proliferation, migration, and invasion. Three subtypes were assigned to patients diagnosed with LGG. Notably, Cluster 2 (C2), exhibiting the poorest survival outcomes, manifested characteristics indicative of the subtype characterized by immunosuppression. This was marked by elevated levels of M1 macrophages, activated mast cells, along with higher immune and stromal scores. Four hub genes—CDCA8, ORC1, DLGAP5, and SMC4—were identified and validated through cell experiments and qPCR. Subsequently, these validated genes were utilized to construct a stemness risk signature. Which revealed that Lower-Grade Glioma (LGG) patients with lower scores were more inclined to demonstrate favorable responses to immune therapy. Our study illuminates the stemness characteristics of gliomas, which lays the foundation for developing therapeutic approaches targeting CSCs and enhancing the efficacy of current immunotherapies. By identifying the stemness subtype and its correlation with prognosis and TME patterns in glioma patients, we aim to advance the development of personalized treatments, enhancing the ability to predict and improve overall patient prognosis.

Abnormalities of several oncogenes and tumor suppressor genes have been identified in carcinomas during the last decade and of pathological warfare and physiological traits, and multiple genetic changes have been demonstrated in individual carcinomas. We conducted a systematic review of studies enrolling adolescents and adults with Carcinoma, every type in which a cancer intervention was randomized, or all study designs in which there was a primary or secondary outcome. We searched Ovid MEDLINE, EMBASE, and Evidence-Based Medicine Reviews from 1990 to June 2015. Two reviewers evaluated study eligibility and abstracted data. In total, 67 studies were included and consisted of 62 randomized trials, reviews, and 5 studies. None of the studies (0/81) provided a definition. Only one randomized trial provided a definition. We were unable to identify any definitions used in studies of adolescents and adults with Carcinoma. Given that a proportion of this population may receive intensive treatment, there is an urgent need for consensus-based definitions of use across trials and review systematic & and meta-analysis.

Human induced pluripotent stem cells (hiPSCs) have great potential to be used as alternatives to embryonic stem cells (hESCs) in regenerative medicine and disease modelling. In this study, we characterise the proteomes of multiple hiPSC and hESC lines derived from independent donors and find that while they express a near-identical set of proteins, they show consistent quantitative differences in the abundance of a subset of proteins. hiPSCs have increased total protein content, while maintaining a comparable cell cycle profile to hESCs, with increased abundance of cytoplasmic and mitochondrial proteins required to sustain high growth rates, including nutrient transporters and metabolic proteins. Prominent changes detected in proteins involved in mitochondrial metabolism correlated with enhanced mitochondrial potential, shown using high-resolution respirometry. hiPSCs also produced higher levels of secreted proteins, including growth factors and proteins involved in the inhibition of the immune system. The data indicate that reprogramming of fibroblasts to hiPSCs produces important differences in cytoplasmic and mitochondrial proteins compared to hESCs, with consequences affecting growth and metabolism. This study improves our understanding of the molecular differences between hiPSCs and hESCs, with implications for potential risks and benefits for their use in future disease modelling and therapeutic applications.

By inhibiting receptor-ligand interactions in sebaceous glands, antibodies may be able to treat certain skin conditions.

Background Understanding human stem cell differentiation into osteoblasts and osteoclasts is crucial for bone regeneration and disease modeling. Numerous morphological techniques have been employed to assess this differentiation, but a comprehensive review of their application and effectiveness is lacking. Methods Guided by the PRISMA framework, we conducted a rigorous search through the PubMed, Web of Science and Scopus databases, analyzing 254 articles. Each article was scrutinized against pre-defined inclusion criteria, yielding a refined selection of 14 studies worthy of in-depth analysis. Results The trends in using morphological approaches were identified for analyzing osteoblast and osteoclast differentiation. The three most used techniques for osteoblasts were Alizarin Red S (mineralization; six articles), von Kossa (mineralization; three articles) and alkaline phosphatase (ALP; two articles) followed by one article on Giemsa staining (cell morphology) and finally immunochemistry (three articles involved Vinculin, F-actin and Col1 biomarkers). For osteoclasts, tartrate-resistant acid phosphatase (TRAP staining) has the highest number of articles (six articles), followed by two articles on DAPI staining (cell morphology), and immunochemistry (two articles with VNR, Cathepsin K and TROP2. The study involved four stem cell types: peripheral blood monocyte, mesenchymal, dental pulp, and periodontal ligament. Conclusion This review offers a valuable resource for researchers, with Alizarin Red S and TRAP staining being the most utilized morphological procedures for osteoblasts and osteoclasts, respectively. This understanding provides a foundation for future research in this rapidly changing field.

Precision gene editing in primary hematopoietic stem and progenitor cells (HSPCs) would facilitate both curative treatments for monogenic disorders as well as disease modelling. Precise efficiencies even with the CRISPR/Cas system, however, remain limited. Through an optimization of guide RNA delivery, donor design, and additives, we have now obtained mean precise editing efficiencies >90% on primary cord blood HSCPs with minimal toxicity and without observed off-target editing. The main protocol modifications needed to achieve such high efficiencies were the addition of the DNA-PK inhibitor AZD7648, and the inclusion of spacer-breaking silent mutations in the donor in addition to mutations disrupting the PAM sequence. Critically, editing was even across the progenitor hierarchy, did not substantially distort the hierarchy or affect lineage outputs in colony-forming cell assays or the frequency of high self-renewal potential long-term culture initiating cells. As modelling of many diseases requires heterozygosity, we also demonstrated that the overall editing and zygosity can be tuned by adding in defined mixtures of mutant and wild-type donors. With these optimizations, editing at near-perfect efficiency can now be accomplished directly in human HSPCs. This will open new avenues in both therapeutic strategies and disease modelling.

Objectives: It is thought that Taiwanese indigenous people were the “first people” to populate Taiwan (Formosa) having been there for over 5000 years, preceding the Dutch colonization (from 1624 to 1662) and Spanish colonization (from 1626 to 1642). Taiwan's indigenes, represented by Austronesian language speakers, currently constitute approximately 2% of the total population in Taiwan. It is unknown whether they evolved from Taiwan's Paleolithic or Neolithic cultures, arrived during or after the Neolithic period from China or Southeast Asia or both. HLA studies on the Taiwanese indigenous population have found several intriguing genetic information showing one or two relatively frequently observed alleles and a small number of relatively less frequently observed ones. We report here a relatively frequently observed HLA-C*07:359 allele in the Taiwanese indigenous population, its linkage with HLA-B*39:01, and its probable associated HLA haplotype in two Taiwanese indigenous families. HLA-C*07:359 is a rarely observed allele in the HLA-C locus in the world populations. The objective of this study is to report the allele HLA-C*07:359 that is more frequently found in the Taiwanese population, especially in the Taiwanese indigenous people, to demonstrate that it has a close linkage with HLA-B*39:01 allele in the HLA-B locus and to show the plausible deduced HLA-A-C-B-DRB1-DQB1 haplotypes in association with HLA-C*07:359 in two families of Taiwanese indigenous unrelated individuals. Materials and Methods: The samples were peripheral whole blood, with dipotassium ethylenediaminetetraacetic acid and/or acid citrate dextrose anticoagulation additives. The sequence-based typing method was employed to confirm the low incidence of the allele of HLA-C*07:359 observed in Taiwanese. Polymerase chain reaction was carried out to amplify exons 2, 3, and 4 of the HLA-A,-B,-C,-DRB1 and-DQB1 loci with group-specific primer sets. Amplicons were sequenced using the BigDye Terminator Cycle Sequencing Ready Reaction Kit in both directions according to the manufacturer's protocol. Results: C*07:359 is an uncommon allele in the HLA-C locus in the world general population, according to our literature review. However, in this study, it is observed in the general Taiwanese population (frequency 0.41%), especially in the Taiwanese indigenous people at a frequency of 0.23%. In addition, we deduced two probable HLA haplotypes in association with C*07:359 in two indigenous families: A*24:02-C*07:359-B*39:01-DRB1*04:36 and A*24:02-C*07:359-B*39:01-DRB1*04:04. Conclusion: The two deduced HLA haplotypes associated with the uncommon C*07:359 allele that we report here are valuable for HLA tissue typing laboratories for reference purposes and for stem cell transplantation donor search coordinators to determine the likelihood of finding compatible donors in unrelated bone marrow donor registries for patients bearing the uncommon HLA allele. Since C*07:359 was found mostly in the Taiwanese indigenous population, we think the allele and its haplotypes we report here are important in population and anthropological studies.

Abstract Exosomes are tiny extracellular vesicles secreted by most cell types, which are filled with proteins, lipids, and nucleic acids (non-coding RNAs, mRNA, DNA), can be released by donor cells to subsequently modulate the function of recipient cells. Skin photoaging is the premature aging of the skin structures over time due to repeated exposure to ultraviolet (UV) which is evidenced by dyspigmentation, telangiectasias, roughness, rhytides, elastosis, and precancerous changes. Exosomes are associated with aging-related processes including, oxidative stress, inflammation, and senescence. Anti-aging features of exosomes have been implicated in various in vitro and pre-clinical studies. Stem cell-derived exosomes can restore skin physiological function and regenerate or rejuvenate damaged skin tissue through various mechanisms such as decreased expression of matrix metalloproteinase (MMP), increased collagen and elastin production, and modulation of intracellular signaling pathways as well as, intercellular communication. All these evidences are promising for the therapeutic potential of exosomes in skin photoaging. This review aims to investigate the molecular mechanisms and the effects of exosomes in photoaging.

Sensory nerves belong to the afferent nerve part of the peripheral nervous system. Their role is to accept the stimuli inside and outside the body and transmit them to the center nerve system to form sensations or reflexes. Sensory nerve damage can be caused by trauma, tumor invasion, surgical injury, etc. Sensory nerve injury may cause decline or loss of some sensory organs function in patients. Damage of important sensory nerves such as optic nerves and auditory nerves can bring profound troubles to patients' lives. So far, the main clinical method to repair sensory nerves is autologous nerve transplantation. However, its application is limited by various factors, and the recovery effect of nerve function is often limited. Stem cells have the potential of multi-directional differentiation, which can differentiate into Schwann cells, and then secrete neurotrophic factors to promote axonal growth and myelin regeneration. Schwann cells directionally proliferate and form Büngner zones which guide nerve regeneration. Stem cells can also differentiate into neurons and construct nerve defect repair materials, which is an ideal choice for nerve repair. At present, the tissue engineering technology based on stem cells, combined with several key biotechnology, such as the use of biopolymerized or artificial surface micro-patterning nerve conduit to bridge nerve defects, and the use of microspheres to achieve the controlled release of extracellular matrix proteins and neurotrophic factors, is being widely studied and has achieved certain research results. This article reviews the research progress of stem cells in the repair of several major sensory nerves, such as optic nerves, olfactory nerves, cochlear nerves and sensory nerve fibers of sciatic nerve, expecting to provide a new perspective for neural repair of stem cells, broaden the preclinical research in nerve repair, and provide reference for follow-up clinical application.

Abstract TAR DNA-binding protein 43 (TDP-43) is a versatile RNA/DNA-binding protein with multifaceted processes. While TDP-43 has been extensively studied in the context of degenerative diseases, recent evidence has also highlighted its crucial involvement in diverse life processes beyond neurodegeneration. Here, we mainly reviewed the function of TDP-43 in non-neurodegenerative physiological and pathological processes, including spermatogenesis, embryonic development, mammary gland development, tumor formation, and viral infection, highlighting its importance as a key regulatory factor for the maintenance of normal functions throughout life. TDP-43 exhibits diverse and sometimes opposite functionality across different cell types through various mechanisms, and its roles can shift at distinct stages within the same biological system. Consequently, TDP-43 operates in both a context-dependent and a stage-specific manner in response to a variety of internal and external stimuli. Video Abstract

Alveoli are an important part of the respiratory system whose function is to exchange oxygen and carbon dioxide molecules from the bloodstream. Maintaining the integrity and barrier function of the alveoli requires complex interactions of multiple cell lineages. Hence, comprehensive understanding of the biology of lung stem cells could improve the treatment of patients with lung disorders such as acute respiratory distress syndrome, fibrotic lung disease and cancer. This review focuses on recent progresses on mammalian alveolar stem cell subpopulations and PSC-derived lung models and discusses insights about the regeneration-specific cell status of alveolar stem cells. We also provide future directions for an improved understanding of post-injury lung repair processes and lung diseases.

The remarkable similarity between non-human primates (NHPs) and humans establishes them as essential models for understanding human biology and diseases, as well as for developing novel therapeutic strategies, thereby providing more comprehensive reference data for clinical treatment. Pluripotent stem cells such as embryonic stem cells and induced pluripotent stem cells provide unprecedented opportunities for cell therapies against intractable diseases and injuries. As continue to harness the potential of these biotechnological therapies, NHPs are increasingly being employed in preclinical trials, serving as a pivotal tool to evaluate the safety and efficacy of these interventions. Here, we review the recent advancements in the fundamental research of stem cells and the progress made in studies involving NHPs.

Background: Stem cells have been widely used in various fields of the health sector, one of which is dental health. Teeth with malocclusion require orthodontic treatment to achieve good function and aesthetics. Orthodontic tooth movement (OTM) occurs due to a bone remodeling process, namely deposition in areas of tension and resorption in areas of pressure. Differentiated stem cells are thought to influence OTM through several different mechanisms. Purpose: This narrative review seeks to explain how stem cells affect the mobility of orthodontic teeth. Review(s): OTM is aided by inflammatory mediators that are produced as a result of the induction of stem cells in the periodontal ligament. These mediators control osteoclast and osteoblast differentiation and proliferation, as well as bone remodeling. Periodontal ligament stem cells (PDLSCs) are important local immune response modulators in the inflammatory milieu and have an impact on a range of immune cells. Conclusion: PDLSCs, which are included in mesenchymal stem cells (MSCs), play a role in OTM through various mechanisms that can cause acceleration in OTM.

Abstract Electrical impulses from cardiac pacemaker cardiomyocytes initiate cardiac contraction and blood pumping and maintain life. Abnormal electrical impulses bring patients with low heart rates to cardiac arrest. The current therapy is to implant electronic devices to generate backup electricity. However, complications inherent to electronic devices remain unbearable suffering. Therefore, cardiac biological pacing has been developed as a hardware-free alternative. The approaches to generating biological pacing have evolved recently using cell reprogramming technology to generate pacemaker cardiomyocytes in-vivo or in-vitro. Different from conventional methods by electrical re-engineering, reprogramming-based biological pacing recapitulates various phenotypes of de novo pacemaker cardiomyocytes and is more physiological, efficient, and easy for clinical implementation. This article reviews the present state of the art in reprogramming-based biological pacing. We begin with the rationale for this new approach and review its advances in creating a biological pacemaker to treat bradyarrhythmia.

Introduction: Although there have been many studies on stem cells, few have investigated how neurotransmitters and stem cell proliferation interact to regenerate dental pulp. Dental pulp regeneration is an innovative procedure for reviving dental pulp, if feasible for the entire tooth. Upon tooth injury, activated platelets release serotonin and dopamine in bulk to mobilize dental pulp stem cells to mediate natural dental repair. This has induced research on the role of neurotransmitters in increasing the proliferation rate of stem cells. This review also covers prospective future treatments for dental pulp regeneration. Methods: A literature search was performed via PubMed and ScienceDirect from 2001 to 2022, using the keywords “neurotransmitter,” “stem cell,” “tooth regeneration,” “tooth repair,” “regenerative dentistry,” and “dental pulp.” Different inclusion/exclusion criteria were used, and the search was restricted to English articles. Results: Nine publications reporting neurotransmitter interactions with stem cells for tooth and pulp regeneration were selected. Conclusion: Neurotransmitters were found to interact with dental stem cells. Evidence pointing to neurotransmitters as a factor in the increased proliferation of stem cells was found. This review thus gives hope for tooth pulp regeneration and repair.

Systemic toxicity is a major challenge in the development of therapeutics. Consequently, cell-type-specific targeting is needed to improve on-target efficacy while reducing off-target toxicity. Here, we describe a cell-targeting system we have termed BRAID (BRidged Activation by Intra/intermolecular Division) whereby an active molecule is divided into two inactive or less active parts that are subsequently brought together via a so-called ‘bridging receptor’ on the target cell. This concept was validated using the WNT/β-catenin signaling system, demonstrating that a multivalent WNT agonist molecule divided into two inactive components assembled from different epitopes via the hepatocyte receptor βKlotho induces signaling specifically on hepatocytes. These data provide proof of concept for this cell-specific targeting strategy, and in principle, this may also allow activation of multiple signaling pathways where desirable. This approach has broad application potential for other receptor systems.

Background and Aims: Pulp necrosis in immature teeth disrupts root development and makes the teeth susceptible to fracture. Regenerative endodontics is a relatively new modality of treatment where the necrotic pulp is replaced with newly formed healthy tissue which has normal functionality. Many clinical reports have demonstrated the potential of this strategy to induce root maturation and apical closure. However, clinical outcomes are patient-dependent and unpredictable. Developing predictable protocols can be achieved through the interplay of three basic elements of tissue engineering, namely, scaffolds, stem cells, and signaling molecules. Furthermore, the clinical success of this treatment is influenced by both the method of preparing the inner space of the root and the type of biomaterial utilized in the coronal part. In this review, we discuss recent advances in tissue engineering-based strategies for regeneration of the pulp/dentine complex along with their advantages and limitations.

Abstract Background Epithelial-to-mesenchymal transition (EMT) and cancer stem-like cells (CSLCs) play crucial role in tumor metastasis and drug-resistance. Disheveled3 (DVL3) is involved in malignant behaviors of cancer. However, the role and potential mechanism of DVL3 remain elusive in EMT and CSLCs of colorectal cancer (CRC). Methods UALCAN and PrognoScan databases were employed to evaluate DVL3 expression in CRC tissues and its correlation with CRC prognosis, respectively. Transwell, sphere formation and CCK8 assay were used to assess metastasis, stemness and drug sensitivity of CRC cells, respectively. Western blotting and dual luciferase assay were performed to analyze the protein expression and Wnt/β-catenin activation, respectively. Lentiviral transfection was used to construct the stable cell lines. Animal studies were performed to analyze the effect of silencing DVL3 on tumorigenicity and metastasis of CRC cells in vivo. Results DVL3 was overexpressed in CRC tissues and several CRC cell lines. DVL3 expression was also higher in CRC tissues with lymph node metastasis than tumor tissues without metastasis, and correlated with poor prognosis of CRC patients. DVL3 positively regulated the abilities of migration, invasion and EMT-like molecular changes in CRC cells. Moreover, DVL3 promoted CSLCs properties and multidrug resistance. We further identified that Wnt/β-catenin was crucial for DVL3-mediated EMT, stemness and SOX2 expression, while silencing SOX2 inhibited DVL3-mediated EMT and stemness. Furthermore, c-Myc, a direct target gene of Wnt/β-catenin, was required for SOX2 expression and strengthened EMT and stemness via SOX2 in CRC cells. Finally, knockdown of DVL3 suppressed tumorigenicity and lung metastasis of CRC cells in nude mice. Conclusion DVL3 promoted EMT and CSLCs properties of CRC via Wnt/β-catenin/c-Myc/SOX2 axis, providing a new strategy for successful CRC treatment.

Duchenne muscular dystrophy is a highly progressive muscle wasting disease of early childhood and characterized by complex pathophysiological and histopathological changes in the voluntary contractile system, including myonecrosis, chronic inflammation, fat substitution and reactive myofibrosis. The continued loss of functional myofibres and replacement with non-contractile cells, as well as extensive tissue scarring and decline in tissue elasticity, leads to severe skeletal muscle weakness. In addition, dystrophic muscles exhibit a greatly diminished regenerative capacity to counteract the ongoing process of fibre degeneration. In normal muscle tissues, an abundant stem cell pool consisting of satellite cells that are localized between the sarcolemma and basal lamina, provides a rich source for the production of activated myogenic progenitor cells that are involved in efficient myofibre repair and tissue regeneration. Interestingly, the self-renewal of satellite cells for maintaining an essential pool of stem cells in matured skeletal muscles is increased in dystrophin-deficient fibres. However, satellite cell hyperplasia does not result in efficient recovery of dystrophic muscles due to impaired asymmetric cell divisions. The lack of expression of the full-length dystrophin isoform Dp427-M, which is due to primary defects in the DMD gene, appears to affect key regulators of satellite cell polarity causing a reduced differentiation of myogenic progenitors, which are essential for myofibre regeneration. This review outlines the complexity of dystrophinopathy and describes the importance of the pathophysiological role of satellite cell dysfunction. A brief discussion of the bioanalytical usefulness of single cell proteomics for future studies of satellite cell biology is provided.

Highly potent animal stem cells either self renew or launch complex differentiation programs, using mechanisms that are only partly understood. Drosophila female germline stem cells (GSCs) perpetuate without change over evolutionary time and generate cystoblast daughters that develop into nurse cells and oocytes. Cystoblasts initiate differentiation by generating a transient syncytial state, the germline cyst, and by increasing pericentromeric H3K9me3 modification, actions likely to suppress transposable element activity. Relatively open GSC chromatin is further restricted by Polycomb repression of testis or somatic cell-expressed genes briefly active in early female germ cells. Subsequently, Neijre/CBP and Myc help upregulate growth and reprogram GSC metabolism by altering mitochondrial transmembrane transport, gluconeogenesis, and other processes. In all these respects GSC differentiation resembles development of the totipotent zygote. We propose that the totipotent stem cell state was shaped by the need to resist transposon activity over evolutionary timescales.

Experiments on female fruit flies reveal more about the molecular mechanisms involved as germline stem cells transition to become egg cells.

Background Endometrial cancer stem-like cells (ECSCs) have been proven to be responsible for recurrence, metastasis, and drug-resistance in patients with endometrial cancer. The HIPPO pathway has been shown to play an important role in the development and maintenance of stemness in a variety of tumors. While there was less research about its function in ECSCs. The aim of this study was to explore the role of YAP1, a core molecular of HIPPO pathway, in the stemness of endometrial cancer and to reveal its influence on prognosis. Methods We collected specimens and clinical data from 774 patients with endometrial cancer to analyze the correlation between YAP1 expression and prognosis. We then examined the expression of YAP1 in ECSCs and EC cell lines (Ishikawa; HEC1-A) in vitro experiments. Changes in the stemness of cell lines were detected after YAP1 silencing by siRNA. Finally, high-throughput sequencing was used to predict the potential molecular interactions and mechanisms of YAP1’s effect on stemness. Result Down-regulation of YAP1 significantly suppresses the stemness of EC cell lines. High expression of YAP1 leads to poor prognosis in EC by regulation of stemness. Conclusion YAP1 plays an important role in the prognosis of patients with EC by regulation of stemness.

Abstract Background Esophageal squamous cell carcinoma (ESCC) is a deadly gastrointestinal malignancy, and chemotherapy resistance is a key factor leading to its poor prognosis. M2 tumor-associated macrophages (M2-TAMs) may be an important cause of chemoresistance in ESCC, but its exact mechanism is still unclear. Methods In order to study the role of M2-TAMs in ESCC chemoresistance, CCK-8, clone formation assay, flow cytometric apoptosis assay, qRT-PCR, western blotting, and serum-free sphere formation assays were used. In vivo animal experiments and human ESCC tissues were used to confirm the findings. Results In vitro and in vivo animal experiments, M2-TAMs reduced the sensitivity of ESCC cells to cisplatin. Mechanistically, M2-TAMs highly secreted TGF-β1 which activated the TGFβR1-smad2/3 pathway to promote and maintain the stemness characteristic of ESCC cells, which could inhibit the sensitivity to cisplatin. Using TGFβ signaling inhibitor SB431542 or knockdown of TGFβR1 could reverse the cisplatin resistance of ESCC cells. In 92 cases of human ESCC tissues, individuals with a high density of M2-TAMs had considerably higher levels of TGF-β1. These patients also had worse prognoses and richer stemness markers. Conclusion TGF-β1 secreted from M2-TAMs promoted and maintained the stemness characteristic to induce cisplatin resistance in ESCC by activating the TGFβ1-Smad2/3 pathway.

Abstract Background Regenerative medicine has the potential to treat genetic disorders and replace damaged or missing tissue. The use of donor or animal tissue raises many well-known issues, including limited tissue availability, the possibility of rejection and patient infection. Stem cell therapy raised hope of overcoming these issues, but created new risks including tumour formation and limited benefit if the desired target tissue does not form. The recent development of 3-dimensional tissues, including organoids, allows the creation of more complex tissues for personalised regenerative medicine. Methods This article details the potential health risks of 3-dimensional organoid and tissue therapy versus dissociated stem cell therapy. The current ethical and regulatory issues surrounding 3-dimensional organoid and tissue therapy are presented with a focus on the highly influential FDA and International Society of Stem Cell Research (ISSCR) guidelines. Conclusions The potential use of 3-dimensional organoid and tissue therapy may deliver greater patient benefits than other regenerative medicine approaches, but raises new health and ethical risks. Preclinical testing of these therapies will not mitigate some of their risks; they may only be understood after first-in-human trials. The potential irreversibility and high risk of these therapies affects how clinical trials should be structured, including post-trial care for participants.

ObjectiveTo analyze the effectiveness and safety of clinical use of different types of stem cells to provide evidence for governmental supervision of key issues in clinical utilization of stem cells.MethodsSix literature databases in China and abroad were searched for relevant literature published from January 2010 to July 2020， and a systematic review was conducted.ResultsThe study showed 72 studies concerning the effectiveness and safety of different types of stem cells in clinical utilization. Although clinical utilization of stem cells had some therapeutic effects for certain diseases， their long-term effect and safety need to be further evaluated， especially their potential risk of tumorigenicity.ConclusionTo protect the patients’ interest， physicians should fully weigh the benefits against the risks of clinical utilization of stem cells， and relevant governmental departments should strengthen supervision of ethics of clinical research and therapies involving stem cells as well as supervision of stem cell products.

In the paper， national and international ethical requirements and supervision on stem cell research and clinical application were analyzed after literature review. It is suggested that the development of stem cell technology should be timely tracked， prospective ethical research related to stem cells should be enhanced， and that stem cell research and clinical translation should comply with relevant international ethical guidelines and national regulations in China. In addition， it is indicated that the oversight of stem cell products and their clinical use will be continuously improved in our country.

Objective: The human large intergenic non-coding RNA-regulator of reprogramming program (linc-ROR) is known as astem cell specific linc-RNA. linc-ROR counteracts differentiation via sequestering microRNA-145 (miR-145) that targets OCT4 transcript. Despite the research on the expression and function, the exact structure of Linc-ROR transcripts is not clear. Considering the contribution of alternative splicing in transcripts structures and function, identifying different spliced variants of linc-ROR is necessary for further functional analyses. We aimed to find the alternatively spliced transcripts of linc-ROR and investigate their expression pattern in stem and cancer cell lines and during neural differentiation of NT2 cells as a model for understanding linc-ROR role in stem cell and differentiation.Materials and Methods: In this experimental study, linc-ROR locus was scanned for identifying novel exons. Different primer sets were used to detect new spliced variants by reverse transcription polymerase chain reaction (RT-PCR) and direct sequencing. Quantitative PCR (qPCR) and RT-PCR were employed to profile expression of linc-ROR transcripts in different cell lines and during neural differentiation of stem cells.Results: We could discover 13 novel spliced variants of linc-ROR harboring unique array of exons. Our work uncoveredsix novel exons, some of which were the product of exonized transposable elements. Monitoring expression profile of the linc-ROR spliced variants in a panel of pluripotent and non-pluripotent cells exhibited that all transcripts were primarily expressed in pluripotent cells. Moreover, the examined linc-ROR spliced variants showed a similar downregulation during neural differentiation of NT2 cells.Conclusion: Altogether, our data showed despite the difference in the structure and composition of exons, various spliced variants of linc-ROR showed similar expression pattern in stem cells and through differentiation.

Salivary gland function impairment is one example of a Type 2 Diabetes Mellitus (T2DM) consequence caused by a loss of microcirculation. Mesenchymal stem cells' (MSCs) metabolite may modulate the immune response and fight pathogen infection through the synthesis of cathelicidin (LL-37) for tissue regeneration. Objectives to investigate the active compound of the MSCs' metabolite, namely cathelicidin (LL-37), which binds to the effects of interleukin (IL)-10, IL-17, vascular endothelial growth factor (VEGF), fibroblast growth factor-2 (FGF-2), tumor growth factor beta (TGFß), insulin growth factor (IGF), platelet-derived growth factor (PDGF), epidermal growth factor (EGF), hepatocyte growth factor (HGF), tissue inhibitor matrix metalloproteinase-1 (TIMP-1), matrix metalloproteinase (MMP)- 8 and -9, dectin, flaggelin, and peptidoglycan through a bioinformatics approach, in silico study. RCSB PDB was used to prepare the peptide Cathelicidin (LL37) (RCSB ID: 2K6O) and the biomarker targets for IL-10, VEGF, FGF2, IGF, HGF, EGF, TGFß, PDGF, TIMP-1, Dectin, Flagelin, Peptidoglycan, IL-17, MMP-9, and MMP-8. PyMol v2.5 software for molecular docking optimization and standard publication-style visualization was used to remove water molecules and ligand impurities from target surfaces. Cathelicidin (LL-37) has a great negative binding energy value with IL-10, VEGF, FGF2, IGF, HGF, EGF, TGFß, PDGF, TIMP1, Dectin, Flagelin, Peptidoglycan, IL-17, MMP-9, and MMP-8. Cathelicidins (LL-37) in MSC's metabolite has high negative binding energy value that may inhibits pro-inflammatory cytokines, microbial, tissue degradation enzyme related biomarkers and increase anti-inflammatory cytokines and growth factor as documented in silico. [ABSTRACT FROM AUTHOR]

Co-regulated genes of the Imprinted Gene Network are involved in the control of growth and body size, and imprinted gene dysfunction underlies human paediatric disorders involving the endocrine system. Imprinted genes are highly expressed in the pituitary gland, among them, Dlk1, a paternally expressed gene whose membrane-bound and secreted protein products can regulate proliferation and differentiation of multiple stem cell populations. Dosage of circulating DLK1 has been previously implicated in the control of growth through unknown molecular mechanisms. Here we generate a series of mouse genetic models to modify levels of Dlk1 expression in the pituitary gland and demonstrate that the dosage of DLK1 modulates the process of stem cell commitment with lifelong impact on pituitary gland size. We establish that stem cells are a critical source of DLK1, where embryonic disruption alters proliferation in the anterior pituitary, leading to long-lasting consequences on growth hormone secretion later in life.

Curing cancer has always presented a formidable clinical challenge. Among the various treatment strategies for combating tumors, the combination of targeted therapy and immunotherapy has recently assumed significant importance. Regrettably, while targeted drugs demonstrate efficiency in the early stages of cancer treatment, patients inevitably develop drug resistance as treatment progresses, ultimately resulting in treatment failure and death. Currently, effective countermeasures against drug-resistant tumor cells remain limited, and research into the mechanisms of drug resistance continues to garner profound interest. The current understanding of drug resistance primarily focuses on two aspects: intrinsic or primary drug resistance, and acquired or secondary drug resistance. Further explanations delve into molecular mechanisms, including acquired gene mutations, epigenetic modifications, the plasticity of cancer stem cells, and the mediation of exosomes. With the advancement of single-cell analysis, our understanding of these potential mechanisms has become more comprehensive. In this review, we initially explore classical signaling pathways related to tumorigenesis and cancer cell progression. Additionally, we summarize recent findings regarding gene mutations and modifications related to drug resistance in cancer. Finally, we discuss the plasticity of cancer stem cells and the latest research on exosome-mediated tumor drug resistance.

Extracellular vesicles (EVs) are lipid bilayer-enclosed structures released by cells and encapsulate bioactive cargoes that act as an emerging messenger of intercellular communication in the development of kidney diseases. Currently, an increasing number of studies documented that, urinary EVs are packed with proteins and RNAs derived from renal resident cells, which could be served as a source of diagnostic biomarker. Furthermore, EVs are natural nanocarriers in the body with intrinsic characteristics, including great biocompatibility, low immunogenicity and low toxicity， which makes them great potential to apply for the treatment of kidney diseases. This review will focus on the current studies on EVs-based theranostics of kidney diseases.

As a highly conserved signal pathway in evolution, the WNT signaling pathway plays an essential role in periodontium growth, development and injury repair. The Axin-associated protein Axin2 is a direct effector molecule of the WNT signaling pathway and labels WNT-responsive cells well. Studies have shown that Axin2-positive (Axin2+) cells in the periodontium have the potential for self-renewal, replication and multidirectional differentiation. This article reviews the temporal and spatial distribution of Axin2+ cells in periodontal tissue development and the role and regulatory mechanism of Axin2+ cells in periodontal tissue development, regeneration and tissue remodeling to provide new ideas for periodontal tissue regeneration. The literature review showed that Axin2+ cells were the main cell source of periodontium development, and Axin2+ cells played essential roles in tooth extraction socket healing, implant osseointegration, periodontal tissue remodeling and junctional epithelium regeneration. The function of Axin2+ cells was positively regulated by the canonical WNT signaling pathway. However, the regulatory mechanisms of other signaling pathways on Axin2+ cells remain to be elucidated.

Idiopathic pulmonary fibrosis (IPF) consists of fibrotic alveolar remodeling and progressive loss of pulmonary function. Genetic and experimental evidence indicates that chronic alveolar injury and failure to properly repair the respiratory epithelium are intrinsic to IPF pathogenesis. Loss of alveolar type 2 (AT2) stem cells or mutations that either impair their self-renewal and/or impair their differentiation into AT1 cells can serve as a trigger of pulmonary fibrosis. Recent reports indicate increased YAP activity in respiratory epithelial cells in IPF lungs. Individual IPF epithelial cells with aberrant YAP activation in bronchiolized regions frequently co-express AT1, AT2, conducting airway selective markers and even mesenchymal or EMT markers, demonstrating ‘indeterminate’ states of differentiation and suggesting that aberrant YAP signaling might promote pulmonary fibrosis. Yet, Yap and Taz have recently also been shown to be important for AT1 cell maintenance and alveolar epithelial regeneration after Streptococcus pneumoniae-induced injury. To investigate how epithelial Yap/Taz might promote pulmonary fibrosis or drive alveolar epithelial regeneration, we inactivated the Hippo pathway in AT2 stem cells resulting in increased nuclear Yap/Taz, and found that this promotes their alveolar regenerative capacity and reduces pulmonary fibrosis following bleomycin injury by pushing them along the AT1 cell lineage. Vice versa, inactivation of both Yap1 and Wwtr1 (encoding Taz) or Wwtr1 alone in AT2 cell stem cells impaired alveolar epithelial regeneration and resulted in increased pulmonary fibrosis upon bleomycin injury. Interestingly, the inactivation of only Yap1 in AT2 stem cells promoted alveolar epithelial regeneration and reduced pulmonary fibrosis. Together, these data suggest that epithelial Yap promotes, and epithelial Taz reduces pulmonary fibrosis suggesting that targeting Yap but not Taz-mediated transcription might help promote AT1 cell regeneration and treat pulmonary fibrosis.

Background and objective: The aims of this study were to create Bisphonates Related Osteonecrosis of the Jaw (BRONJ) in rats and treat them with an angiogenesis factor (A-Heal) and ABMDO (Autologous Bone Marrow Derived Osteoblasts). Materials and methods: Thirty female Wistar rats were procured. Rats were labeled as Group I to III. Group I = Osteoblast group, Group II = A-Heal and Group III Control group. In Groups I-III, BRONJ was created and treated in Group I with ABMDO, Group II with A-Heal and Group III was the control group. At the end of the four weeks post treatment, all the animals were humanely killed. The intact maxillae were removed in total. Histopathological and radiological examinations were carried out with physicians blinded to the groups. Results: Computerized tomography revealed that Groups I and II demonstrated the presence of dense osteosclerosis, intralesional calcifications, and adequate healing of the overlying soft tissues compared to Group III, which showed the presence of bone erosions at the alveolar ridge with a lack of intralesional calcifications and ulceration of the overlying soft tissues. Histologically, H&E staining Group 1 and Group 2 both showed marked reactive bone formation. Group 2 additionally revealed the most prominent vascular proliferation (also highlighted by Factor VIII, an endothelial cell marker) among all groups. Group 3 showed cartilaginous proliferation with less reactive bone formation, implicating decreased endochondral ossification compared to Groups 1 and 2. Conclusion: This study shows that angiogenesis factor (A-Heal) and ABMDO were successful in the treatment of experimentally created BRONJ in an animal model.

Sustenance of visual function is the ultimate focus of ophthalmologists. Failure of complete recovery of visual function and complications that follow conventional treatments have shifted search to a new form of therapy using stem cells. Stem cell progenitors play a major role in replenishing degenerated cells despite being present in low quantity and quiescence in our body. Unlike other tissues and cells, regeneration of new optic cells responsible for visual function is rarely observed. Understanding the transcription factors and genes responsible for optic cells development will assist scientists in formulating a strategy to activate and direct stem cells renewal and differentiation. We review the processes of human eye development and address the strategies that have been exploited in an effort to regain visual function in the preclinical and clinical state. The update of clinical findings of patients receiving stem cell treatment is also presented.

Proper differentiation of sperm from germline stem cells, essential for production of the next generation, requires dramatic changes in gene expression that drive remodeling of almost all cellular components, from chromatin to organelles to cell shape itself. Here, we provide a single nucleus and single cell RNA-seq resource covering all of spermatogenesis in Drosophila starting from in-depth analysis of adult testis single nucleus RNA-seq (snRNA-seq) data from the Fly Cell Atlas (FCA) study. With over 44,000 nuclei and 6000 cells analyzed, the data provide identification of rare cell types, mapping of intermediate steps in differentiation, and the potential to identify new factors impacting fertility or controlling differentiation of germline and supporting somatic cells. We justify assignment of key germline and somatic cell types using combinations of known markers, in situ hybridization, and analysis of extant protein traps. Comparison of single cell and single nucleus datasets proved particularly revealing of dynamic developmental transitions in germline differentiation. To complement the web-based portals for data analysis hosted by the FCA, we provide datasets compatible with commonly used software such as Seurat and Monocle. The foundation provided here will enable communities studying spermatogenesis to interrogate the datasets to identify candidate genes to test for function in vivo.

Brain development is a unique process characterized by mechanisms defined as neuroplasticity (synaptogenesis, synapse elimination, neurogenesis, and cerebral angiogenesis). Numerous neurodevelopmental disorders brain damage, and aging are manifested by neurological deficits that are caused by aberrant neuroplasticity. The presence of stem and progenitor cells in neurogenic niches of the brain is responsible for the formation of new neurons capable of integrating into preexisting synaptic assemblies. The determining factors for the cells within the neurogenic niche are the activity of the vascular scaffold and the availability of active regulatory molecules that establish the optimal microenvironment. It has been found that regulated intramembrane proteolysis plays an important role in the control of neurogenesis in brain neurogenic niches. Molecules generated by the activity of specific proteases can stimulate or suppress the activity of neural stem and progenitor cells, their proliferation and differentiation, migration and integration of newly formed neurons into synaptic networks. Local neoangiogenesis supports the processes of neurogenesis in neurogenic niches, which is guaranteed by the multivalent action of peptides formed from transmembrane proteins. Identification of new molecules regulating the neuroplasticity (neurogenesis and angiogenesis). i. e. enzymes, substrates, and products of intramembrane proteolysis, will ensure the development of protocols for detecting the neuroplasticity markers and targets for efficient pharmacological modulation.

Mechanisms communicating changes in tissue stiffness and size are particularly relevant in the intestine because it is subject to constant mechanical stresses caused by peristalsis of its variable content. Using the Drosophila intestinal epithelium, we investigate the role of vinculin, one of the best characterised mechanoeffectors, which functions in both cadherin and integrin adhesion complexes. We discovered that vinculin regulates cell fate decisions, by preventing precocious activation and differentiation of intestinal progenitors into absorptive cells. It achieves this in concert with α-catenin at sites of cadherin adhesion, rather than as part of integrin function. Following asymmetric division of the stem cell into a stem cell and an enteroblast (EB), the two cells initially remain connected by adherens junctions, where vinculin is required, only on the EB side, to maintain the EB in a quiescent state and inhibit further divisions of the stem cell. By manipulating cell tension, we show that vinculin recruitment to adherens junction regulates EB activation and numbers. Consequently, removing vinculin results in an enlarged gut with improved resistance to starvation. Thus, mechanical regulation at the contact between stem cells and their progeny is used to control tissue cell number.

Background There have been promising results published regarding the potential of stem cells in regenerative medicine. However, the vast variety of choices of techniques and the lack of a standard approach to analyse human osteoblast and osteoclast differentiation may reduce the utility of stem cells as a tool in medical applications. Therefore, this review aims to systematically evaluate the findings based on stem cell differentiation to define a standard gene expression profile approach. Methods This review was performed following the PRISMA guidelines. A systematic search of the study was conducted by retrieving articles from the electronic databases PubMed and Web of Science to identify articles focussed on gene expression and approaches for osteoblast and osteoclast differentiation. Results Six articles were included in this review; there were original articles of in vitro human stem cell differentiation into osteoblasts and osteoclasts that involved gene expression profiling. Quantitative polymerase chain reaction (qPCR) was the most used technique for gene expression to detect differentiated human osteoblasts and osteoclasts. A total of 16 genes were found to be related to differentiating osteoblast and osteoclast differentiation. Conclusion Qualitative information of gene expression provided by qPCR could become a standard technique to analyse the differentiation of human stem cells into osteoblasts and osteoclasts rather than evaluating relative gene expression. RUNX2 and CTSK could be applied to detect osteoblasts and osteoclasts, respectively, while RANKL could be applied to detect both osteoblasts and osteoclasts. This review provides future researchers with a central source of relevant information on the vast variety of gene expression approaches in analysing the differentiation of human osteoblast and osteoclast cells. In addition, these findings should enable researchers to conduct accurately and efficiently studies involving isolated human stem cell differentiation into osteoblasts and osteoclasts.

Basal cells are multipotent stem cells of a variety of organs, including the respiratory tract, where they are major components of the airway epithelium. However, it remains unclear how diverse basal cells are and how distinct subpopulations respond to airway challenges. Using single cell RNA-sequencing and functional approaches, we report a significant and previously underappreciated degree of heterogeneity in the basal cell pool, leading to identification of six subpopulations in the adult murine trachea. Among these, we found two major subpopulations, collectively comprising the most uncommitted of all the pools, but with distinct gene expression signatures. Notably, these occupy distinct ventral and dorsal tracheal niches and differ in their ability to self-renew and initiate a program of differentiation in response to environmental perturbations in primary cultures and in mouse injury models in vivo. We found that such heterogeneity is acquired prenatally, when the basal cell pool and local niches are still being established, and depends on the integrity of these niches, as supported by the altered basal cell phenotype of tracheal cartilage-deficient mouse mutants. Finally, we show that features that distinguish these progenitor subpopulations in murine airways are conserved in humans. Together, the data provide novel insights into the origin and impact of basal cell heterogeneity on the establishment of regionally distinct responses of the airway epithelium during injury-repair and in disease conditions.