Caveolin-1 forms a complex with P2X7 receptor and tunes P2X7-mediated ATP signaling in mouse bone marrow-derived macrophages

Ca2+ microdomains in vascular smooth muscle cells: Roles in vascular tone regulation and hypertension

Vascular smooth muscle cells (VSMCs) modulate blood pressure by adjusting vascular contractility. Specific families of ion channels that are expressed in VSMCs regulate membrane potential and intracellular Ca2+ concentration ([Ca2+]cyt). Subsets of them are known to form molecular complexes with Ca2+-sensitive molecules via scaffolding proteins such as caveolin and junctophilin. This enables localized and molecular complex-specific signal transduction to regulate vascular contractility. This intracellular region is referred to as a Ca2+ microdomain. When hypertensive stimuli are applied to blood vessels, gene expression of ion channels and scaffold proteins in vascular cells changes dramatically, often leading to membrane depolarization and increased [Ca2+]cyt. As a result, blood vessels undergo functional remodeling characterized by enhanced contractility. In addition, the transcription of inflammatory genes in vascular cells is also upregulated. This induces leukocyte infiltration into the vascular wall and structural remodeling mediated by VSMC proliferation and extracellular matrix remodeling. This functional and structural remodeling perpetuates the hypertensive state, leading to progressive damage to systemic organs. This review summarizes recent findings on the mechanisms by which Ca2+ microdomains in VSMCs regulate contractility. In addition, the changes in Ca2+ microdomains due to hypertensive stimuli and their contributions to both functional and structural remodeling are summarized.

Pyroptosis for osteoarthritis treatment: insights into cellular and molecular interactions inflammatory

Osteoarthritis (OA) is a widely prevalent chronic degenerative disease often associated with significant pain and disability. It is characterized by the deterioration of cartilage and the extracellular matrix (ECM), synovial inflammation, and subchondral bone remodeling. Recent studies have highlighted pyroptosis-a form of programmed cell death triggered by the inflammasome-as a key factor in sustaining chronic inflammation. Central to this process are the inflammatory cytokines interleukin-1β (IL-1β) and interleukin-18 (IL-18), which play crucial roles mediating intra-articular pyroptosis through the NOD-like receptor protein 3 (NLRP3) inflammasome. This paper investigates the role of the pyroptosis pathway in perpetuating chronic inflammatory diseases and its linkage with OA. Furthermore, it explores the mechanisms of pyroptosis, mediated by nuclear factor κB (NF-κB), the purinergic receptor P2X ligand-gated ion channel 7 (P2X7R), adenosine monophosphate (AMP)-activated protein kinase (AMPK), and hypoxia-inducible factor-1α (HIF-1α). Additionally, it examines the interactions among various cellular components in the context of OA. These insights indicate that targeting the regulation of pyroptosis presents a promising therapeutic approach for the prevention and treatment of OA, offering valuable theoretical perspectives for its effective management.

Targeting Caveolin-1 for enhanced rotator cuff repair: findings from single-cell RNA sequencing

Rotator cuff injury (RCI), a prevalent cause of shoulder pain and disability, often leads to significant functional impairments due to adipocyte infiltration into the damaged tissue. Caveolin-1 (Cav-1), a critical membrane protein, plays a significant role in adipocyte differentiation and lipid metabolism. This study utilized single-cell RNA sequencing (scRNA-seq) to investigate the heterogeneity of cell subpopulations in RCI tissues and assess the regulatory effects of Cav-1. The findings revealed that Cav-1 expression negatively correlates with adipogenic activity, and its modulation through exercise or targeted therapies can significantly reduce adipocyte infiltration and enhance tissue repair. Further, Cav-1 knockout and overexpression models demonstrated the protein's impact on key genes involved in adipocyte differentiation and lipid metabolism, such as Scd1, fatty acid synthase (FASN), and peroxisome proliferator-activated receptor gamma (Pparg). Animal studies corroborated these results, showing that exercise intervention increased Cav-1 expression, decreased adipocyte infiltration, and promoted structural repair. These insights suggest that targeting Cav-1 could offer a novel therapeutic strategy for improving RCI outcomes.

Caveolin-1-mediated LDL transcytosis across endothelial cells in atherosclerosis

Atherosclerosis is widely recognized as a chronic inflammatory disease of the arterial wall characterized by the progressive accumulation of lipids, inflammatory cells, and fibrous material in the subendothelial space of large arteries. The occurrence and pathogenesis of atherosclerosis are intricately linked to the deposition of low-density lipoprotein (LDL) in the arterial wall. LDL must cross the intact endothelium to reach the subendothelial space, with caveolin-1 assuming a crucial role in this process. Caveolin-1 is a 21-24 kDa membrane protein located in caveolae and highly expressed in endothelial cells. Previous investigations have demonstrated the pivotal role of caveolin-1 in fostering atherosclerosis through its modulation of membrane trafficking, cholesterol metabolism, and cellular signaling. However, how caveolin-1 regulates LDL transcytosis across endothelial cells in atherosclerosis remains unclear. We provide a comprehensive overview of recent research on the interplay between caveolin-1 and atherosclerosis, with a specific focus on elucidating the role of caveolin-1 in mediating LDL transcytosis across endothelial cells. This review furnishes theoretical foundations supporting the pivotal role of caveolin-1 in both the inception and progression of atherosclerosis. It underscores the prospective viability of caveolin-1 as a new therapeutic target for atherosclerosis and introduces novel perspectives for treatment strategies in the early stages of atherosclerosis.

Comprehensive insights into potential roles of purinergic P2 receptors on diseases: Signaling pathways involved and potential therapeutics

BACKGROUND

Purinergic P2 receptors, which can be divided into ionotropic P2X receptors and metabotropic P2Y receptors, mediate cellular signal transduction of purine or pyrimidine nucleoside triphosphates and diphosphate. Based on the wide expression of purinergic P2 receptors in tissues and organs, their significance in homeostatic maintenance, metabolism, nociceptive transmission, and other physiological processes is becoming increasingly evident, suggesting that targeting purinergic P2 receptors to regulate biological functions and signal transmission holds significant promise for disease treatment.

AIM OF REVIEW

This review highlights the detailed mechanisms by which purinergic P2 receptors engage in physiological and pathological progress, as well as providing prospective strategies for discovering clinical drug candidates.

KEY SCIENTIFIC CONCEPTS OF REVIEW

The purinergic P2 receptors regulate complex signaling and molecular mechanisms in nervous system, digestive system, immune system and as a result, controlling physical health states and disease progression. There has been a significant rise in research and development focused on purinergic P2 receptors, contributing to an increased number of drug candidates in clinical trials. A few influential pioneers have laid the foundation for advancements in the evaluation, development, and of novel purinergic P2 receptors modulators, including agonists, antagonists, pharmaceutical compositions and combination strategies, despite the different scaffolds of these drug candidates. These advancements hold great potential for improving therapeutic outcomes by specifically targeting purinergic P2 receptors.

Ca2+ signaling in vascular smooth muscle and endothelial cells in blood vessel remodeling: a review

Vascular smooth muscle cells (VSMCs) and endothelial cells (ECs) act together to regulate blood pressure and systemic blood flow by appropriately adjusting blood vessel diameter in response to biochemical or biomechanical stimuli. Ion channels that are expressed in these cells regulate membrane potential and cytosolic Ca2+ concentration ([Ca2+]cyt) in response to such stimuli. The subsets of these ion channels involved in Ca2+ signaling often form molecular complexes with intracellular molecules via scaffolding proteins. This allows Ca2+ signaling to be tightly controlled in localized areas within the cell, resulting in a balanced vascular tone. When hypertensive stimuli are applied to blood vessels for extended periods, gene expression in these vascular cells can change dramatically. For example, alteration in ion channel expression often induces electrical remodeling that produces a depolarization of the membrane potential and elevated [Ca2+]cyt. Coupled with endothelial dysfunction blood vessels undergo functional remodeling characterized by enhanced vasoconstriction. In addition, pathological challenges to vascular cells can induce inflammatory gene products that may promote leukocyte infiltration, in part through Ca2+-dependent pathways. Macrophages accumulating in the vascular adventitia promote fibrosis through extracellular matrix turnover, and cause structural remodeling of blood vessels. This functional and structural remodeling often leads to chronic hypertension affecting not only blood vessels, but also multiple organs including the brain, kidneys, and heart, thus increasing the risk of severe cardiovascular events. In this review, we outline recent advances in multidisciplinary research concerning Ca2+ signaling in VSMCs and ECs, with an emphasis on the mechanisms underlying functional and structural vascular remodeling.