Cell and Tissue Research最新文献

Limb injuries such as severe strains, deep cuts, gunshot wounds, and ischemia can cause peripheral nerve damage. This can result in a range of clinical symptoms including sensory deficits, limb paralysis and atrophy, neuralgia, and sweating abnormalities in the innervated areas affected by the damaged nerves. These symptoms can have a significant impact on patients' daily lives and work. Despite existing clinical treatments, some patients cannot achieve satisfactory therapeutic effects and continue to experience persistent paralysis and pain. Schwann cells are responsible for repairing and regenerating damaged nerves in the peripheral nervous system. They play a crucial role in the healing of nerve injuries and are essential for the restoration of proper nerve function. An increasing number of studies have focused on the various regulatory mechanisms that specifically affect the repair of damage by Schwann cells. This article aims to provide information on the different types of peripheral nerve injuries and their available treatments. We also discuss the various molecular mechanisms that regulate Schwann cell function during peripheral nerve repair and how they can be used to promote nerve repair and regeneration. Furthermore, we explore the potential therapeutic applications of precision regulation of Schwann cells for the treatment of peripheral nerve injuries.

We have previously reported detailed structures of the mucosal nerve network in the rat ileum, but the mechanisms underlying the development of this nerve network remain unclear. Therefore, we aimed to clarify the developmental process of the mucosal nerve network and submucosal neurons (SM-neurons) or ganglia (SMG), which are the main source of nerve fibers projected to the mucosa, in the rat ileum during the postnatal period. Immunohistochemistry against tubulin beta III (Tuj1) revealed that Tuj1-immunopositivities were more abundant in the lamina propria at 2 weeks old (2wk; pre-weaning) than at postnatal day 0 (P0) or 4 weeks old (4wk; post-weaning) and more frequent on the mesenteric side than on the antimesenteric side at 2wk. Hu antigen D (HuD)-immunopositive SM-neurons and SMG were also more abundantly localized on the mesenteric side than the antimesenteric side at P0 and 2wk. On the other hand, cells immunopositive for SRY-related HMG-box 10 (Sox10), which is the marker for enteric nervous system progenitor cells and enteric glial cells, were homogenously scattered in the submucosa throughout the entire circumference at all ages. Glial cell marker S100 calcium-binding protein B (S100β) in the submucosa was detected at all ages without any significant difference between the mesenteric and antimesenteric sides. These findings indicate that SMG formation and associated neurite extension into the mucosa in the rat ileum might occur preferentially on the mesenteric side by the weaning period, leading us to hypothesize that the mechanism by which the mucosal nerve network and SMG develop differs along the mesenteric-antimesenteric side axis.

Hieroglyphus banian (H. banian) is a grasshopper species, endemic to South Asia. The optic lobe in Acrididae has been characterized to a great extent in orthoptera, predominantly using Locust species like Schistocerca gregaria, Schistocerca americana, and Locusta migratoria, which are closely related to each other. In this work, we characterize the anatomical features of the optic lobe and associated pathway in the grasshopper species H. banian using tract tracing, immunohistochemistry, and intracellular fills. All the areas of the visual pathways that have been reported in the other orthoptera species could be identified in H. banian. Visual pathways exhibited similar structure and connectivity as shown in immunohistochemistry and tract-tracing results supporting the conservation of these features across species within Acrididae. Two new structures in the posterior protocerebrum, PS1 and PS2 with prominent innervations from the optic lobe were identified. Novel structure PS1 is innervated from medulla via PS1T and, PS2 from aMe via PS2T, both new tracts we have identified.

Airway smooth muscle (ASM) dysfunction is a key factor in the narrowing of airways in asthma patients, characterized by excessive secretion of inflammatory factors, increased mass, and amplified contractile responses. These pathological features are instrumental in the propagation of airway inflammation, structural remodeling, and the escalation of airway hyperresponsiveness (AHR), which are also principal factors underlying the limitations of current therapeutic strategies. In asthmatic ASM, an imbalance between oxidant production and antioxidant defenses culminates in oxidative stress, which is involved in the excessive secretion of inflammatory factors, increased mass, and amplified contractile responses of ASM, and is a critical etiological factor implicated in the dysregulation of ASM function. The molecular pathways through which oxidative stress exerts its effects on ASM in asthma are multifaceted, with the Nrf2/HO-1, MAPK, and PI3K/Akt pathways being particularly noteworthy. These characteristic pathways play a potential role by connecting with different upstream and downstream signaling molecules and are involved in the amplification of ASM inflammatory responses, increased mass, and AHR. This review provides a comprehensive synthesis of the phenotypic expression of ASM dysfunction in asthma, the interplay between oxidants and antioxidants, and the evidence base and molecular underpinnings linking oxidative stress to ASM dysfunction. Given the profound implications of ASM dysfunction on the airflow limitation in asthma and the seminal role of oxidative stress in this process, a deeper exploration of these mechanisms is essential for unraveling the pathogenesis of asthma and may offer novel perspectives for its prophylaxis and management.

Blastocyst complementation can potentially generate a rodent model with humanized nasopharyngeal epithelium (NE) that supports sustained Epstein-Barr virus (EBV) infection, enabling comprehensive studies of EBV biology in nasopharyngeal carcinoma. However, during this process, the specific gene knockouts required to establish a developmental niche for NE remain unclear. We performed bioinformatics analyses and generated Foxa1 mutant mice to confirm that Foxa1 disruption could potentially create a developmental niche for NE. Subsequently, MYD88-inactivated human pluripotent stem cells (hPSCs) were constructed and complemented with Foxa1-deficient mouse blastocysts, with Nosip-deficient mouse blastocysts as a control. The chimerism of human cells in mouse embryos was evaluated from E8.5 to E12.5 using genomic DNA PCR and immunohistochemistry. Our bioinformatics analysis indicated that the expression patterns of Foxa1 in E8.5 to E16.5 mouse embryos underscore its critical role in NE development. The generated mice with Foxa1 disordered region mutations displayed morphological abnormality in NE, suggesting Foxa1-knockouts could potentially establish a developmental niche for NE. In chimeric assays, human cells integrated into 80.00% of Foxa1-deficient embryos, compared with the 4.17% in controls. Immunohistochemistry results revealed robust proliferation of human cells in Foxa1-deficient mouse embryos. However, chimeras from Foxa1-deficient mouse embryos did not survive beyond E10.5, hindering the evaluation of human cell integration in mouse NE. Foxa1 disruption in mouse embryos significantly enhances the integration of human cells in human-mouse interspecies chimeras, thereby facilitating the generation of endoderm-derived organs through blastocyst complementation. Overcoming chimeras' embryonic lethality is crucial for successfully generating humanized NE in Foxa1-deficient mouse embryos.

A detailed understanding of the precise regulatory mechanisms governing buffalo skeletal muscle is crucial for improving meat quality and yield. Proper skeletal muscle fate decisions necessitate the accurate regulation of key enhancers. This study screened nine potential enhancers linked to muscle development by analysing ATAC-seq data from buffalo myoblasts during the proliferative and differentiative phases. The enhancer activity of these candidates was confirmed in buffalo myoblasts, C2C12, and human skeletal muscle myoblasts using a dual-luciferase reporter system. The CRISPRi system and RT-qPCR were used to test the effects of 9 candidate enhancers on buffalo myoblasts. The active enhancer, Enh483, was selected based on its significant impact. Upon successful inhibition of Enh483 using CRISPRi, decreases in the expression of buffalo myogenic proliferation marker genes (PCNA, CyclinD1, and CDK2) were observed via RT-qPCR and Western blot. Subsequent proliferation assays using CCK-8 and EdU confirmed the promotive effect of Enh483 on buffalo myogenic cell proliferation. Following a 5-day differentiation induction period, changes in the expression of differentiation marker genes (MyoD1, MyoG, and MyHC) were analysed using RT-qPCR and Western blot. Additionally, fused myotube numbers were quantified, and the impact of Enh483 on buffalo myogenic cell differentiation was assessed through immunofluorescence. Our findings indicate that Enh483 facilitates buffalo myogenic cell differentiation. Further interaction analysis utilising 3C-PCR revealed a direct association between Enh483 and the FAXC promoter. In summary, the results from this study lay a foundational framework for deciphering the intricate regulatory mechanisms underpinning buffalo muscle development.

The adult electric organ in weakly electric mormyrid fish consists of action-potential-generating electrocytes, structurally and functionally modified skeletal muscle cells. The electrocytes have a disc-shaped portion and, on one of its sides, numerous thin processes, termed stalklets. These unite to stalks leading to a single main stalk that carries the innervation site. Here, we describe the 3-dimensional layout of the stalklet/stalk system in adult Campylomormyrus compressirostris by differential interference contrast microscopy and confocal fluorescence microscopy. Using antibodies against Na⁺/K⁺-ATPase α-subunit and plasma membrane Ca²⁺-ATPase, we show that these ion pumps are differentially distributed over the stalklet/stalk system, with plasma membrane Ca²⁺-ATPase being enriched on the stalklet membrane. Stalklets are distributed and organized in a quite uniform pattern on the posterior face of the electrocyte disc and fuse to terminal stalks. The latter then unite in a mostly dichotomic mode to stalks of increasing thickness, with the main stalk measuring about 100 µm in diameter. We further analyse the structural organization of stalklets and stalks, with a characteristic cytoskeletal system of bundled actin filaments in the centre and nuclei in subsurface position. These results suggest that the stalklet/stalk system is adapted in its structural layout to generate an action potential highly synchronized over the entire disc-portion of the electrocyte, accounting for the short electric organ discharge in this species. Our results suggest that actin-related proteins overexpressed in electrocytes, as shown previously by transcriptome analysis, may be involved in the organization of the unique F-actin system in stalklets and stalks.

Sustenance of ischemia in the surviving cardiac tissue following myocardial infarction (MI) elicits a proinflammatory milieu resulting in subsequent pathological episodes. Also, the activation and release of ribosomal proteins under ischemic insults have been unveiled; however, their extra ribosomal functions are unknown. We identified the ribosomal proteins including RPL10A, RPL14, RPL30, RPS18, FAU-40 (RPS30), and RPSA (Laminin Receptor, LR) in the vesicles of ischemia challenged epicardial adipose tissue derived stromal cells (EATDS). The present study aimed to assess the association of these proteins in the epicardial adipose tissues (EAT) and left ventricular (LV) myocardium and isolated stromal cells (EATDS and LVSCs) from hyperlipidemic (HL), MI and coronary artery bypass graft (CABG) swine models. The findings revealed an upregulation of RPL10A, RPL14, RPL30, RPS18, RPS30, and RPSA in the LV tissues of CABG and HL swine with a concomitant reduction in the MI group. RPS30 displayed similar upregulation in EAT, whereas the expression of other ribosomal proteins was not significantly altered. Additionally, the ischemic LVSCs and EATDS displayed altered expression status of these genes compared to the control. Also, the RPS18 + , RPL30 + and RPSA + LVSCs favored ischemia and revealed similar anti-inflammatory and regenerative sub-phenotypes reflecting the protective/survival mechanisms. Further understanding regarding the underlying molecular mechanisms and functions of these ribosomal proteins offers immense translational opportunities in the better management of ischemic cardiac complications.

Alpha-synuclein (α-syn) is widely expressed in presynaptic neuron terminals, and its structural alterations play an important role in the pathogenesis of Parkinson's disease (PD). Aggregated α-syn has been found in brain, in the peripheral nerves of the enteric nervous system (ENS) and in the intestinal neuroendocrine cells during synucleinopathies and inflammatory bowel disorders. In the present study, we evaluated the histomorphological features of murine colon with 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis, a common model of colitis. Thereafter, we investigated the expression of α-syn, Toll-like receptor 4 (TLR4), choline acetyltransferase (ChAT), vasoactive intestinal peptide (VIP), tyrosine hydroxylase (TH), calcitonin gene-related peptide (CGRP), and calcitonin-like receptor (CALCR). Finally, we investigated the presence of phosphorylated α-syn (pS129 α-syn) aggregates and their relationship with inflammatory cells. Colon from TNBS mice showed an increase in inflammatory cells infiltrate and significative changes in the architecture of the intestinal mucosa. α-Syn expression was significantly higher in inflamed colon. VIP was increased in both the mucosa and muscularis externa of TNBS mice, while TH, CGRP, and CALCR were significantly reduced in TNBS mice. Amyloid aggregates of pS129 α-syn were detectable in the ENS, as in the macrophages around the glands of the mucosa correlating with the markers of inflammation. This study describes - for the first time - the altered expression of α-syn and the occurrence of amyloid α-syn aggregates in the inflammatory cells under colitis, supporting the critical role of bowel inflammation in synucleinopathies and the involvement of α-syn in IBD.