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Asthma is a heterogeneous disease that varies in clinical presentation, severity, and underlying biology but consistently involves airway remodeling (AR) and airway hyperresponsiveness (AHR), which is characterized by excessive airway narrowing in response to various stimuli. Airway smooth muscle (ASM) cells are primary contributors to airway hyperresponsiveness and bronchoconstriction. This review focuses on ASM cells and their role in asthma. We discuss the mechanisms by which ASM mediates AHR, increases airway thickness, and contributes to AR. Signaling through G protein-coupled receptors (GPCRs) regulates many ASM functions, including contraction, growth, and the synthetic activities that drive airway inflammation and remodeling. GPCR-dependent calcium flux serves as a key signaling axis controlling the contractile responses of ASM. Here we provide a comprehensive summary of the major GPCRs as well as other non-GPCRs identified in ASM cells. GPCR-induced calcium mobilization, downstream signaling and how it has been linked to specific ASM functions are also discussed. Furthermore, we highlight the clinical significance of targeting GPCRs in asthma therapy as well as recent development of novel therapeutics in the management of asthma. Thus, this review provides a comprehensive overview of airway smooth muscle in the context of asthma pathophysiology.

The Special Issue "Glioblastoma: What Do We Know [...].

Bidirectional communication between the central nervous system and the immune system is crucial for brain function, particularly in regulating neuroplasticity: on the one hand, glial cells modulate neuronal function, brain circuitry, axon myelination, dendritic spine architecture, and information processing, while on the other hand, neuronal activity can alter the immune response. Neuroinflammation and dysregulation of astroglia and microglia can be detrimental to brain development and function. In particular, maladaptive responses and chronic glial activation have been correlated to synaptic dysfunction in diverse brain conditions. In the present review, we will provide a general introduction to the main players of the neuroimmune response and their ability to modulate neuroplasticity, followed by a comprehensive overview of experimental evidence linking the dysregulation of immune mediators to the disruption of synaptic plasticity in neurodegenerative and neurodevelopmental disorders, with a specific focus on Alzheimer's disease, Parkinson's disease, and autism spectrum disorder.

Cytokine storm is a critical driver of acute respiratory distress syndrome and multiple organ failure. Human β-defensin 2 (HBD-2) is the first inducible defensin discovered in human body. Defensin can resist pathogenic microorganisms invading the body through direct bactericidal effect and also modulates acquired immune response. Albumin exhibits immunomodulatory properties and can reduce the level of inflammatory cytokines to improve the systemic inflammatory response. We previously engineered a recombinant fusion protein, DF₂-HSA, comprising two HBD-2 molecules linked to human serum albumin. Here, we evaluated its effect on cytokine storm using a lipopolysaccharide (LPS)-induced cytokine storm murine model (BALB/c athymic mice, female). DF₂-HSA reduced the mortality in cytokine storm murine model and prolonged the retention time of HBD-2 in the body. A Luminex assay showed that DF₂-HSA reduced the production of multiple inflammatory cytokines in cytokine storm murine model. Evans blue staining showed that DF₂-HSA reduced vascular leakage. Transmission electron microscopy showed that DF₂-HSA reduced the lung injury of cytokine storm mice. The pathological results showed that DF₂-HSA alleviated the lung and small intestine damage of cytokine storm mice. In summary, DF₂-HSA effectively inhibits cytokine storms and ameliorates associated tissue damage.

GNE myopathy is a rare genetic neuromuscular disorder caused by mutations in the GNE gene. The respective gene product, UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase (GNE), is a bifunctional enzyme that initiates endogenous sialic acid biosynthesis. Sialic acids are important building blocks for the glycosylation machinery of cells and are typically found at the terminal ends of glycoprotein N- and O-glycans. The exact pathomechanism of GNE myopathy remains elusive, and a better understanding of the disease is urgently needed for the development of therapeutic strategies. The purpose of this study was to examine the effects of hyposialylation on glycan structures and subsequent downstream effects in the C2C12 Gne knockout cell model. No overall remodeling of N-glycans was observed in the absence of Gne, but differences in glycosaminoglycan expression and O-GlcNAcylation were detected. Expression analysis of myopathogenes revealed concomitant down-regulation of muscle-specific genes. Among the top candidates were the sodium channel protein type 4 subunit α (Scn4a), voltage-dependent L-type calcium channel subunit α-1s (Cacna1s), ryanodine receptor 1 (Ryr1), and glycogen phosphorylase (Pygm), which are associated with excitation-contraction coupling and energy metabolism. The results suggest that remodeling of the glycome could have detrimental effects on intracellular signaling, excitability of skeletal muscle tissue, and glucose metabolism.

Neurodegenerative diseases are distinguished by synaptic dysfunction and chronic neuroinflammation, which accelerate neuronal loss and impair network resilience. Synaptic plasticity, that is, the ability to adapt to changes, is progressively lost. This ability is part of hormesis, an adaptive biphasic response, nowadays acknowledged as a promising tool in chronic degenerative diseases, since it offers a framework for personalized interventions. Growing evidence supports exercise as a powerful approach for managing neurodegenerative disorders, due to its capacity to enhance neuroplasticity through the direct targeting of the biomolecular processes involved. Indeed, regular exercise can drive many molecular mediators and signals toward neuroplasticity improvement, potentially slowing neurodegeneration. This narrative review focuses on exercise as a promising therapeutic approach in neurodegenerative diseases, based on its ability to shape synaptic plasticity at the molecular level. Some biomediators involved in synaptic plasticity function/dysfunction and neuroinflammation/neurodegeneration are addressed as therapeutic targets of exercise, and different exercise regimens are discussed as specific therapeutic interventions to contain the burden of some neurodegenerative conditions. Some clinical trials including exercise in the treatment of neurodegenerative diseases are summarized. Since no definitive disease-modifying cure exists for these illnesses, exercise's ability to shape synaptic plasticity emerges as a highly attractive therapeutic approach.

Acid-sensing ion channels (ASICs), activated under acidic conditions, play a critical role in ischemic brain injury, but the detailed mechanisms and signaling pathways remain unclear. Our previous studies have shown that activation of ASIC1a channels contributes to acidosis-induced neuronal injury, partially mediated by increased calcium influx. In this study, we provide evidence that activation of ASIC2a-containing channels induces zinc influx. In cultured mouse cortical neurons, ASIC currents that were insensitive to PcTx1 inhibition were potentiated by extracellular zinc. In Chinese Hamster Ovary cells transfected with different ASIC subunits, large inward currents were recorded upon a pH drop from 7.4 to 5.0 in cells expressing homomeric ASIC1a, ASIC2a, or heteromeric ASIC1a/2a channels when normal Na⁺-rich extracellular fluid (ECF) was used. However, when ECF was modified to one containing zinc as the primary cation, the same pH drop induced an inward current only in cells expressing homomeric ASIC2a or heteromeric ASIC1a/2a, but not homomeric ASIC1a. Fluorescence imaging revealed rapid zinc influx in cells expressing ASIC2a but not ASIC1a when zinc was applied with the acidic ECF. Additionally, at pH values where ASIC2a-containing channels were activated, acid-mediated neurotoxicity was exacerbated by zinc. Thus, ASIC2a-containing channels may represent a novel pathway for zinc entry and activation of these channels might contribute to zinc-mediated neurotoxicity.

Diabetes mellitus encompasses a heterogeneous group of metabolic disorders defined by abnormalities in insulin secretion, function, or both. Exogenous insulin therapy has long been the principal treatment strategy for patients with type 1 diabetes and for those in advanced stages of type 2 diabetes. Stem cell therapy has gained significant attention in recent years as a potential curative approach for several life-threatening disorders. In this review, we focus on the use of induced pluripotent stem cells as an alternative source for beta-cell generation, offering a solution to organ scarcity and providing a sustainable supply of insulin-producing cells. We further evaluate current developments in encapsulation technologies and transplantation sites, while noting that the issue of immune-mediated graft rejection continues to be widely debated. The aim of this review is to outline encapsulation techniques and transplantation approaches explored in animal models, and to discuss the risks and challenges anticipated in human clinical trials.

The oncogene KRAS drives tumor growth by activating pathways such as MAPK and PI3K-AKT in a constitutive manner. Although direct KRAS inhibitors exist, they are often limited in clinical use due to therapeutic resistance and toxicity. Therefore, alternative combinatorial therapeutic strategies are urgently needed. This study examined the knockout of five KRAS-related proteins-galectin-3 (GAL3), phosphodiesterase delta (PDEδ), nucleophosmin (NPM1), IQ motif-containing GTPase-activating protein 1 (IQGAP1), and SHOC2-using CRISPR-Cas9 in adenocarcinoma cell lines harboring the KRAS(G12V) oncogenic mutation, as well as in the noncancerous HEK-293 cell line. These proteins act as critical modulators that regulate KRAS activity, cellular localization, and that of its downstream signaling components. We analyzed the downstream activation of ERK and AKT kinases and evaluated subsequent cancer cell proliferation. Knockout of GAL3 and PDEδ was highly effective, significantly reducing MAPK and PI3K-AKT pathway activity and substantially impairing cell proliferation. SHOC2 knockout selectively and potently disrupted MAPK activation, while NPM1 knockout resulted in the complex, reciprocal modulation of the two major pathways. Notably, knocking out IQGAP1 enhanced PI3K-AKT and mTORC2-AKT signaling without affecting the MAPK pathway. These distinct modulatory roles highlight the non-redundant functions of the accessory proteins. In conclusion, our findings establish GAL3 and PDEδ, two KRAS-associated proteins, as promising combinatorial drug targets. Targeting these modulators provides an effective alternative strategy to overcome resistance mechanisms and enhance the clinical utility of existing KRAS inhibitors.

T cells play an important role in the development and progression of type 1 diabetes (T1D). Checkpoint receptors regulate T cell activity, and their expression may be linked to the cells' metabolic state. This study aims to investigate the association between T regulatory (Treg) and T conventional (Tconv) cells expressing various checkpoint inhibitors and glucose metabolism in type 1 diabetes patients and healthy controls (HCs). The study included 28 participants, with 16 of them diagnosed with type 1 diabetes, while 12 constituted a healthy control group. Multicolor flow cytometry, spectrophotometric analysis, and bead-based multiplex assays were utilized for the analyses. The study revealed that the most significant difference in T cell subsets in peripheral blood concerned TIGIT. Compared to healthy subjects, the percentages of TIGIT+ Tregs and TIGIT+ Tconvs were lower in T1D patients. Interestingly, hyperglycemia in in vitro cultures reduced percentages of TIGIT+ Tregs and TIGIT+ Tconvs, and to some extent also CTLA-4+ Tregs. A decreased percentage of these subsets was, in turn, associated with reduced glucose uptake and lower activity of the enzymes responsible for various stages of glucose metabolism. The described associations suggest a negative influence of hyperglycemia in T1D on immune regulation via a TIGIT-dependent mechanism. Hyperglycemia seems to reduce the percentage of highly regulatory TIGIT+ Tregs both in vivo and in vitro, and it is associated with reduced glucose consumption by these cells. At the same time, a reduction in the percentage of TIGIT+ Tconvs under such conditions may facilitate higher activity of Tconvs, including aberrant autoimmune reactions.