Current Opinion in Physiology最新文献

The cellular ‘powerhouse’, mitochondria play vital roles in cardiac cells, including the modulation of contractility. Among the various mechanisms, the modulation of cardiac mitochondria by adrenergic signaling stands out as a crucial component in orchestrating cardiac function. Adrenergic system serving as the primary regulator of cardiac contractility, exerts its effects through α- and ß-adrenoceptors, which are regulated by G-protein-coupled receptor kinase 2 (GRK2) and ß-arrestin. In recent years, it has been revealed that these components of adrenergic signaling interact with mitochondria in diverse ways. α- and ß-adrenoceptors are reported to contribute to mitochondrial biogenesis, dynamics, and function. Besides, GRK2 is known to be localized to mitochondria, following oxidative stress or ischemic injury, and exerts negative metabolic effects. In this review, we outlined the contributions of these pivotal elements of adrenergic signaling to mitochondrial function. The better understanding of this delicate relationship holds crucial implications for novel therapeutic options to treat cardiovascular pathologies.

Vasculopathy is a generic feature of autoimmune rheumatic disease and there is substantial evidence that endothelial cell dysfunction has a role in pathogenesis and clinical manifestations of this challenging group of diseases. Endothelial cells (EC) are a target for injury and through their essential functional role in vascular homoeostasis, this has significant impact. In addition, the emerging recognition that EC are important regulators of other cell types and can differentiate into other relevant cell types has direct relevance. These aspects are reviewed with a focus on recent published evidence regarding the importance of EC in development, progression and treatment of autoimmune rheumatic disease. The potential role of the adaptive and innate immune system in causing endothelial cell damage, including anti-endothelial cell autoantibodies, will be reviewed. Recent advances in understanding how EC may differentiate into mesenchymal lineages and the interplay between physiological roles in healing or tissue repair and dysfunctional responses in acquired connective tissue disease will be reviewed.

The lethality of heart failure, particularly in the context of post-acute sequelae SARS-CoV-2 infection-related myocarditis, necessitates the discovery of the cellular pathways implicated in cardiovascular disease. We summarize the signaling mechanisms of the catecholamine-binding β-adrenergic receptors (β-ARs), with an emphasis on the role of β-arrestins. β-ARs, a subset of G protein-coupled receptors (GPCRs), canonically propagate signals through heterotrimeric G proteins. However, since their discovery in the late 1980s, β-arrestins have been shown to both (i) quench G protein signaling and (ii) initiate their own independent signaling cascades, which is influenced by posttranslational modifications. β-arrestin-biased agonism by the beta-blocker carvedilol and its allosteric modulation can serve a cardioprotective role. The increasingly labyrinthine nature of GPCR signaling suggests that ligand-dependent β-AR signaling, either stimulated by an agonist or blocked by an antagonist, is selectively enhanced or suppressed by allosteric modulations, which are orchestrated by novel drugs or endogenous posttranslational modifications.

The average lifespan of humans is increasing worldwide, and the percentage of older adults is substantially growing. The adrenergic system is a crucial determinant for the cardiovascular homeostasis during aging. In this short review, we discuss the new insights that emerged concerning the role of adrenergic receptors and relative signaling in the aging of the heart and vasculature with particular emphasis on molecular mechanisms involved. We also examine specific therapeutic interventions that modulate the adrenergic system feasibly counteracting and delaying age-induced pathophysiological changes in cardiovascular function and structure.

Adrenergic receptors (AR) are essential regulators of vascular physiology and are largely used as pharmacological targets. This chapter will review the main roles of the vascular AR in both the endothelium and vascular smooth muscle. We will discuss the ability of ARs to regulate key functions in endothelial and smooth muscle cells and their involvement in several pathologic conditions such as hypertension, atherosclerosis, and heart failure.

Cancer progression involves complex interactions between tumor cells and the surrounding microenvironment. Chronic psychosocial stress and sympathetic nervous system activation lead to abnormal catecholamine release, impacting tumor cells directly and indirectly and fuelling cancer-promoting effects. However, the same adrenergic Receptor (AR) that mediate these effects could also convey exercise-related beneficial changes. Epidemiological studies show conflicting associations between stress, AR inhibitors, and breast cancer (BC) metastatic progression. Adrenergic sympathetic stress triggers sustained inflammatory and hypoxic-related signaling pathways, alters function and distribution of immune cell populations, and remodels blood vessels, leading to immunosuppression and premetastatic site formation. Activated AR initiate feedback loops with tyrosine kinase receptors and chemokine receptors, affecting stem-related transcription factors, pro-inflammatory mediators, angiogenic factors, and energy metabolism regulators, promoting tumor growth and invasion. Understanding molecular mechanisms of agonistic and antagonistic AR ligands and crosstalk with other signaling pathways is crucial for developing effective therapies targeting adrenergic-driven BC progression.

Angiogenesis, the process of building new vessels, is important in physiology. In addition, it is involved in different pathologies, including cancers, ischemia, macular degeneration and inflammatory bowel disease. The regulation of angiogenesis is multifaceted and according to recent data includes transcriptional modulation by enhancers and non-coding RNAs as well as post-transcriptional regulation by microRNAs. In this review, we highlight recent findings in this field that relate both to physiological and pathological angiogenesis and discuss the effects on key angiogenic factors.

To survive, all organisms must detect and respond to mechanical cues in their environment. Cells are subjected to a plethora of mechanical forces, such as hydrostatic pressure, cell-cell contact, stretch, compression, and shear stress. Mechanosensitive (MS) membrane proteins have evolved across all life kingdoms to sense and respond to forces in the membrane. Bacterial MS ion channels provide a blueprint for understanding the fundamental mechanisms that underpin cellular responses to mechanical signals. Recently, the identification of eukaryotic force transducers, which includes membrane proteins other than channels, has led to the recognition of common structural hallmarks and unified biophysical mechanisms that could potentially link these diverse proteins. Accumulating evidence suggests G protein-coupled receptors (GPCRs) are candidates for pressure sensing in mammals. This review summarises the current knowledge on MS GPCRs, describes the tools used to assess their mechanosensitivity, and aims to highlight the key characteristics that link these receptors to established mechanosensors.

Myocarditis is frequently caused by viral infections, but animal models that closely resemble human disease suggest that virus-triggered autoimmune disease is the most likely cause of myocarditis. Myocarditis is a rare condition that occurs primarily in men under age 50. The incidence of myocarditis rose at least 15x during the coronavirus disease 2019 (COVID-19) pandemic from 1–10 to 150–400 cases/100 000 individuals, with most cases occurring in men under age 50. COVID-19 vaccination was also associated with rare cases of myocarditis primarily in young men under 50 years of age with an incidence as high as 50 cases/100 000 individuals reported for some mRNA vaccines. Sex differences in the immune response to COVID-19 are virtually identical to the mechanisms known to drive sex differences in myocarditis pre-COVID based on clinical studies and animal models. The many similarities between COVID-19 vaccine-associated myocarditis to COVID-19 myocarditis and non-COVID myocarditis suggest common immune mechanisms drive disease.