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Vietnam is a country most at risk for experiencing climate change effects, especially increasing temperatures. Agricultural production is one of the biggest contributors to Vietnam's economy. Recent research has explored how climate change will impact agriculture in Vietnam. However, the impact of climate change to the health, safety, and wellbeing of Vietnamese farmers is often overlooked. In this study, we conducted five focus groups with 46 farmers representing three provinces of Vietnam. We used a convergent mixed-methods design and a Total Worker Health® framework to assess how farmers in Vietnam experience climate-change-related hazards and describe how famers associate these hazards with impacts to their health, safety, and wellbeing. Multi-dimensional scaling suggests farmers conceptualize hazards separately from health, safety, and wellbeing outcomes, but a thematic analysis of our data indicated that farmers perceive both direct and indirect impacts of climate change to their health, safety, and wellbeing. Direct impacts of climate change described included physical health effects such as heat stress. Indirect impacts included mental health stressors due to productivity demands. Gaps in available health and safety trainings for farmers were also identified. This project demonstrates the need to co-develop safety and health trainings with farmers. System-level approaches both at the societal and community levels are needed. The local governments, cooperatives, Women's Unions, and Farmers' Unions are trusted sources of information that could implement and disseminate these trainings. [ABSTRACT FROM AUTHOR]

Simple Summary: Oxidative stress generates harmful oxygen radicals that activate biomolecules in the lungs of asthmatics. The effects of these mediators are not directly targeted by first-line therapeutics. Using a clinically relevant murine model of allergic asthma, this study reveals that immuno-pharmacological neutralization of oxidized phospholipids in the lung can ameliorate inflammation and asthma symptoms. This suggests that specifically targeting mediators generated by oxidative stress could offer new therapeutic options for asthma to complement conventional therapies. Oxidative stress is associated with asthma pathobiology. We reported that oxidized phosphatidylcholines (OxPCs) are mediators of oxidative stress and accumulate in the lung in response to allergen challenge. The current study begins to unravel mechanisms for OxPC accumulation in the lung, providing the first insights about how OxPCs underpin allergic airway pathophysiology, and pre-clinical testing of selective neutralization of OxPCs in a murine model of allergic asthma. We hypothesized that intranasal delivery of E06, a natural IgM antibody that neutralizes the biological activity of OxPCs, can ameliorate allergen-induced airway inflammation and airway hyperresponsiveness. Adult BALB/c mice were intranasally (i.n.) challenged with house dust mite (HDM) (25 μg/mouse, 2 weeks). Some animals also received E06 monoclonal antibody (mAb) (10 µg) i.n. 1 hr before each HDM challenge. HDM challenge reduced mRNA for anti-oxidant genes (SOD1, SOD2, HO-1, and NFE2L2) in the lung by several orders of magnitude (p < 0.05). Concomitantly, total immune cell number in bronchoalveolar lavage fluid (BALF) increased significantly (p < 0.001). E06 mAb treatment prevented allergen-induced BALF immune cell number by 43% (p < 0.01). This included a significant blockade of eosinophils (by 48%, p < 0.001), neutrophils (by 80%, p < 0.001), macrophages (by 80%, p < 0.05), and CD4 (by 30%, p < 0.05) and CD8 (by 42%, p < 0.01) lymphocytes. E06 effects correlated with a significant reduction in TNF (by 64%, p < 0.001) and IL-1β (by 75%, p < 0.05) and a trend to diminish accumulation of other cytokines (e.g., IL-4, -10, and -33, and IFN-γ). E06 mAb treatment also inhibited HDM exposure-induced increases in total respiratory resistance and small airway resistance by 24% and 26%, respectively. In conclusion, prophylactic treatment with an OxPC-neutralizing antibody significantly limits allergen-induced airway inflammation and airway hyperresponsiveness, suggesting that OxPCs are important mediators of oxidative stress-associated allergic lung pathophysiology. [ABSTRACT FROM AUTHOR]

E-cigarette users predominantly also continue to smoke cigarettes. These Dual Users either consume e-cigarettes in locations where smoking is not allowed, but vaping is, or to reduce their consumption of cigarettes, believing it will lead to harm reduction. Whilst it is known that e-cigarette vapour is chemically less complex than cigarette smoke, it has a distinct chemical profile, and very little is known about the health impacts of exposure to both chemical profiles vs. either alone. We simultaneously exposed cells in vitro to non-toxic levels of e-cigarette vapour extract (EVE) and cigarette smoke extract (CSE) to determine their effects on 16HBE14o- airway epithelial cell metabolism and inflammatory response, as well as immune cell (THP-1 cells and monocyte-derived macrophages (MDM) from healthy volunteers) migration, phagocytosis, and inflammatory response. We observed increased toxicity, reduced metabolism (a marker of proliferation) in airway epithelial cells, and reduced monocyte migration, macrophage phagocytosis, and altered chemokine production after exposure to either CSE or EVE. These cellular responses were greater after dual exposure to CSE and EVE. The airway epithelial cells from smokers showed reduced metabolism after EVE (the Switcher model) and dual CSE and EVE exposure. When EVE and CSE were allowed to interact, the chemicals were found to be altered, and new chemicals were also found compared to the CSE and EVE profiles. Dual exposure to e-cigarette vapour and cigarette smoke led to worse functional outcomes in cells compared to either single exposure alone, adding to limited data that dual use may be more dangerous than smoking only. [ABSTRACT FROM AUTHOR]

Interleukin-8 (IL-8/CXCL8), an essential CXC chemokine, significantly influences psychoneuroimmunological processes and affects neurological and psychiatric health. It exerts a profound effect on immune cell activation and brain function, suggesting potential roles in both neuroprotection and neuroinflammation. IL-8 production is stimulated by several factors, including reactive oxygen species (ROS) known to promote inflammation and disease progression. Additionally, CXCL8 gene polymorphisms can alter IL-8 production, leading to potential differences in disease susceptibility, progression, and severity across populations. IL-8 levels vary among neuropsychiatric conditions, demonstrating sensitivity to psychosocial stressors and disease severity. IL-8 can be detected in blood circulation, cerebrospinal fluid (CSF), and urine, making it a promising candidate for a broad-spectrum biomarker. This review highlights the need for further research on the diverse effects of IL-8 and the associated implications for personalized medicine. A thorough understanding of its complex role could lead to the development of more effective and personalized treatment strategies for neuropsychiatric conditions. [ABSTRACT FROM AUTHOR]

The plant-derived α-linolenic acid (ALA) is an essential n-3 acid highly susceptible to oxidation, present in oils of flaxseeds, walnuts, canola, perilla, soy, and chia. After ingestion, it can be incorporated in to body lipid pools (particularly triglycerides and phospholipid membranes), and then endogenously metabolized through desaturation, elongation, and peroxisome oxidation to eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), with a very limited efficiency (particularly for DHA), beta-oxidized as an energy source, or directly metabolized to C18-oxilipins. At this moment, data in the literature about the effects of ALA supplementation on metabolic syndrome (MetS) in humans are inconsistent, indicating no effects or some positive effects on all MetS components (abdominal obesity, dyslipidemia, impaired insulin sensitivity and glucoregulation, blood pressure, and liver steatosis). The major effects of ALA on MetS seem to be through its conversion to more potent EPA and DHA, the impact on the n-3/n-6 ratio, and the consecutive effects on the formation of oxylipins and endocannabinoids, inflammation, insulin sensitivity, and insulin secretion, as well as adipocyte and hepatocytes function. It is important to distinguish the direct effects of ALA from the effects of EPA and DHA metabolites. This review summarizes the most recent findings on this topic and discusses the possible mechanisms. [ABSTRACT FROM AUTHOR]

Simple Summary: The effects of a rho-kinase inhibitor alone and in combination with a bronchodilator in the presence of a small-amplitude oscillatory strain on the mechanical properties of airway smooth muscle were described in this brief review. Findings from relevant studies provide a strong basis for human trials using rho-kinase alone or in combination with other interventions in the treatment of asthma. Rho-kinase inhibitors have been identified as a class of potential drugs for treating asthma because of their ability to reduce airway inflammation and active force in airway smooth muscle (ASM). Past research has revealed that, besides the effect on the ASM's force generation, rho-kinase (ROCK) also regulates actin filament formation and filament network architecture and integrity, thus affecting ASM's cytoskeletal stiffness. The present review is not a comprehensive examination of the roles played by ROCK in regulating ASM function but is specifically focused on passive tension, which is partially determined by the cytoskeletal stiffness of ASM. Understanding the molecular basis for maintaining active force and passive tension in ASM by ROCK will allow us to determine the suitability of ROCK inhibitors and its downstream enzymes as a class of drugs in treating airway hyperresponsiveness seen in asthma. Because clinical trials using ROCK inhibitors in the treatment of asthma have yet to be conducted, the present review focuses on the in vitro effects of ROCK inhibitors on ASM's mechanical properties which include active force generation, relaxation, and passive stiffness. The review provides justification for future clinical trials in the treatment of asthma using ROCK inhibitors alone and in combination with other pharmacological and mechanical interventions. [ABSTRACT FROM AUTHOR]

Type 2 diabetes (T2D) is a heterogenous disease, and conventionally, peripheral insulin resistance (IR) was thought to precede islet β-cell dysfunction, promoting progression from prediabetes to T2D. New evidence suggests that T2D-lean individuals experience early β-cell dysfunction without significant IR. Regardless of the primary event (i.e., IR vs. β-cell dysfunction) that contributes to dysglycemia, significant early-onset oxidative damage and mitochondrial dysfunction in multiple metabolic tissues may be a driver of T2D onset and progression. Oxidative stress, defined as the generation of reactive oxygen species (ROS), is mediated by hyperglycemia alone or in combination with lipids. Physiological oxidative stress promotes inter-tissue communication, while pathological oxidative stress promotes inter-tissue mis-communication, and new evidence suggests that this is mediated via extracellular vesicles (EVs), including mitochondria containing EVs. Under metabolic-related stress conditions, EV-mediated cross-talk between β-cells and skeletal muscle likely trigger mitochondrial anomalies leading to prediabetes and T2D. This article reviews the underlying molecular mechanisms in ROS-related pathogenesis of prediabetes, including mitophagy and mitochondrial dynamics due to oxidative stress. Further, this review will describe the potential of various therapeutic avenues for attenuating oxidative damage, reversing prediabetes and preventing progression to T2D. [ABSTRACT FROM AUTHOR]

Bronchial asthma is an extremely heterogenous chronic respiratory disorder with several distinct endotypes and phenotypes. These subtypes differ not only in the pathophysiological changes and/or clinical features but also in their response to the treatment. Therefore, precise diagnostics represent a fundamental condition for effective therapy. In the diagnostic process, metabolomic approaches have been increasingly used, providing detailed information on the metabolic alterations associated with human asthma. Further information is brought by metabolomic analysis of samples obtained from animal models. This article summarizes the current knowledge on metabolomic changes in human and animal studies of asthma and reveals that alterations in lipid metabolism, amino acid metabolism, purine metabolism, glycolysis and the tricarboxylic acid cycle found in the animal studies resemble, to a large extent, the changes found in human patients with asthma. The findings indicate that, despite the limitations of animal modeling in asthma, pre-clinical testing and metabolomic analysis of animal samples may, together with metabolomic analysis of human samples, contribute to a novel way of personalized treatment of asthma patients. [ABSTRACT FROM AUTHOR]

It is well known that significant differences exist between males and females in both physiology and disease. Thus, it is important to identify and analyze sex-biased miRNAs. However, previous studies investigating sex differences in miRNA expression have predominantly focused on healthy individuals or restricted their analysis to a single disease. Therefore, it is necessary to comprehensively identify and analyze the sex-biased miRNAs in diseases. For this purpose, in this study, we first identified the miRNAs showing sex-biased expression between males and females in diseases based on a number of miRNA expression datasets. Then, we performed a bioinformatics analysis for these sex-biased miRNAs. Notably, our findings revealed that women exhibit a greater number of conserved miRNAs that are highly expressed compared to men, and these miRNAs are implicated in a broader spectrum of diseases. Additionally, we explored the enriched transcription factors, functions, and diseases associated with these sex-biased miRNAs using the miRNA set enrichment analysis tool TAM 2.0. The insights gained from this study could carry implications for endeavors such as precision medicine and possibly pave the way for more targeted and tailored approaches to disease management. [ABSTRACT FROM AUTHOR]

Allergy and asthma pathogenesis are associated with the dysregulation of metabolic pathways. To understand the effects of allergen sensitization on metabolic pathways, we conducted a multi-omics study using BALB/cJ mice sensitized to house dust mite (HDM) extract or saline. Lung tissue was used to perform untargeted metabolomics and transcriptomics while both lung tissue and plasma were used for targeted lipidomics. Following statistical comparisons, an integrated pathway analysis was conducted. Histopathological changes demonstrated an allergic response in HDM-sensitized mice. Untargeted metabolomics showed 391 lung tissue compounds were significantly different between HDM and control mice (adjusted p < 0.05); with most compounds mapping to glycerophospholipid and sphingolipid pathways. Several lung oxylipins, including 14-HDHA, 8-HETE, 15-HETE, 6-keto-PGF1α, and PGE2 were significantly elevated in HDM-sensitized mice (p < 0.05). Global gene expression analysis showed upregulated calcium channel, G protein–signaling, and mTORC1 signaling pathways. Genes related to oxylipin metabolism such as Cox, Cyp450s, and cPla2 trended upwards. Joint analysis of metabolomics and transcriptomics supported a role for glycerophospholipid and sphingolipid metabolism following HDM sensitization. Collectively, our multi-omics results linked decreased glycerophospholipid and sphingolipid compounds and increased oxylipins with allergic sensitization; concurrent upregulation of associated gene pathways supports a role for bioactive lipids in the pathogenesis of allergy and asthma. [ABSTRACT FROM AUTHOR]

Since COPD is a heterogeneous disease, a specific anti-inflammatory therapy for this disease has not been established yet. Oxidative stress is recognized as a major predisposing factor to COPD related inflammatory responses, resulting in pathological features of small airway fibrosis and emphysema. However, little is known about effects of oxidative stress on airway smooth muscle. Cigarette smoke increases intracellular Ca2+ concentration and enhances response to muscarinic agonists in human airway smooth muscle. Cigarette smoke also enhances proliferation of these cells with altered mitochondrial protein. Hydrogen peroxide and 8-isoprostans are increased in the exhaled breath condensate in COPD. These endogenous oxidants cause contraction of tracheal smooth muscle with Ca2+ dynamics through Ca2+ channels and with Ca2+ sensitization through Rho-kinase. TNF-α and growth factors potentiate proliferation of these cells by synthesis of ROS. Oxidative stress can alter the function of airway smooth muscle through Ca2+ signaling. These phenotype changes are associated with manifestations (dyspnea, wheezing) and pathophysiology (airflow limitation, airway remodeling, airway hyperresponsiveness). Therefore, airway smooth muscle is a therapeutic target against COPD; oxidative stress should be included in treatable traits for COPD to advance precision medicine. Research into Ca2+ signaling related to ROS may contribute to the development of a novel agent for COPD. [ABSTRACT FROM AUTHOR]

Background and Objectives: Asthma constitutes a constant, prolonged, inflammation-related pulmonary disorder in childhood with serious public health concerns. Several maternal risk factors can enhance the prevalence of its development in this stage of life; however, the currently available data remain contradictory and/or inconsistent. We aim to evaluate the potential impacts of mothers' sociodemographic, anthropometric and prenatal and perinatal factors on the prevalence of developing asthma in pre-school children. Materials and Methods: This is a retrospective cross-sectional survey, which includes 5133 women and their matched pre-school children. Childhood asthma was diagnosed using validated questionnaires. Statistical analysis was accomplished to evaluate whether maternal sociodemographic, anthropometric and prenatal and perinatal factors can increase the probability of childhood asthma in pre-school age. Results: A prevalence of 4.5% of childhood asthma was recorded in pre-school age. Maternal age and pre-pregnancy overweight and obesity, caesarean section, gestational diabetes and hypertension and not breastfeeding were associated with childhood asthma after adjustment for multiple confounding factors. Conclusion: Our research showed that several maternal factors increase the prevalence of childhood asthma in pre-school age. Suitable and effective health policies and strategies should be taken into account to confront the predominant maternal factors that increase its prevalence in pre-school age. [ABSTRACT FROM AUTHOR]

Simple Summary: This review is focused on the role of oxidative stress in childhood asthma. The term "oxidative stress" indicates an imbalance between production of radical oxygen species and antioxidant defense systems. Cigarette smoke, allergens, viruses, and other environmental contaminants, as well as a detrimental lifestyle, elevate airway oxidative stress. Uncontrolled oxidative stress within airways amplifies inflammatory responses and tissue damage and alters immune responses, thus increasing the risk of asthma onset and asthma progression in children. Early lifestyle and dietary interventions and use of new antioxidant therapies to restore oxidant/antioxidant balance are all valuable strategies to preserve airway homeostasis. Exposure to cigarette smoke, allergens, viruses, and other environmental contaminants, as well as a detrimental lifestyle, are the main factors supporting elevated levels of airway oxidative stress. Elevated oxidative stress results from an imbalance in reactive oxygen species (ROS) production and efficiency in antioxidant defense systems. Uncontrolled increased oxidative stress amplifies inflammatory processes and tissue damage and alters innate and adaptive immunity, thus compromising airway homeostasis. Oxidative stress events reduce responsiveness to corticosteroids. These events can increase risk of asthma into adolescence and prompt evolution of asthma toward its most severe forms. Development of new therapies aimed to restore oxidant/antioxidant balance and active interventions aimed to improve physical activity and quality/quantity of food are all necessary strategies to prevent asthma onset and avoid in asthmatics evolution toward severe forms of the disease. [ABSTRACT FROM AUTHOR]

In this paper, we want to refute the notion that the microbiota should be considered an organ, given that an organ comprises tissue of similar or different embryological origin, while the microbiota is a pool of different microbial species originating individually from single replications and not from a common ancestral cellular element. Hence, we would like to propose a new morphological interpretation of its nature, based on the comprehensive context in which these microbes live: a muco-microbiotic layer of hollow organs, such as the airways and the bowel. The above concept should represent not only a new terminological annotation but also a more accurate portrayal of the physiology and pathophysiology of these organs. Indeed, a better understanding of the biological nature of this part of the human body can help scientists develop more specific experimental protocols, potentially leading to the establishment of better therapeutic strategies. [ABSTRACT FROM AUTHOR]

Background: Sarcopenia seems to be an emerging health issue worldwide, concerning the progressive loss of skeletal muscle mass, accompanied by adverse outcomes. Asthma is a chronic inflammatory respiratory condition that is widespread in the world, affecting approximately 8% of adults. Although data are scarce, we aim to shed light on the potential association between low muscle mass and asthma and point out any probable negative feedback on each other. Methods: We searched within the PubMed, Scopus, MEDLINE, and Google Scholar databases. Study selections: Three studies were included in our analysis. Only original studies written in English were included, while the references of the research articles were thoroughly examined for more relevant studies. Moreover, animal model studies were excluded. Results: 2% to 17% of asthmatics had sarcopenia according to the existent literature. Sarcopenic asthmatic patients seem to have reduced lung function, while their mortality risk may be increased. Furthermore, patients with asthma- chronic obstructive pulmonary disease (COPD) overlap syndrome phenotype and sarcopenia might have a higher risk of osteopenia and osteoporosis progression, leading consequently to an increased risk of fractures and disability. Conclusions: Emerging data support that pulmonologists should be aware of the sarcopenia concept and be prepared to evaluate the existence of low muscle mass in their asthmatic patients. [ABSTRACT FROM AUTHOR]

Obesity is rapidly becoming a global health problem affecting about 13% of the world's population affecting women and children the most. Recent studies have stated that obese asthmatic subjects suffer from an increased risk of asthma, encounter severe symptoms, respond poorly to anti-asthmatic drugs, and ultimately their quality-of-life decreases. Although, the association between airway hyperresponsiveness (AHR) and obesity is a growing concern among the public due to lifestyle and environmental etiologies, however, the precise mechanism underlying this association is yet to establish. Apart from aiming at the conventional antiasthmatic targets, treatment should be directed towards ameliorating obesity pathogenesis too. Understanding the pathogenesis underlying the association between obesity and AHR is limited, however, a plethora of obesity pathologies have been reported viz., increased pro-inflammatory and decreased anti-inflammatory adipokines, depletion of ROS controller Nrf2/HO-1 axis, NLRP3 associated macrophage polarization, hypertrophy of WAT, and down-regulation of UCP1 in BAT following down-regulated AMPKα and melanocortin pathway that may be correlated with AHR. Increased waist circumference (WC) or central obesity was thought to be related to severe AHR, however, some recent reports suggest body mass index (BMI), not WC tends to exaggerate airway closure in AHR due to some unknown mechanisms. This review aims to co-relate the above-mentioned mechanisms that may explain the copious relation underlying obesity and AHR with the help of published reports. A proper understanding of these mechanisms discussed in this review will ensure an appropriate treatment plan for patients through advanced pharmacological interventions., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

The term asthma-COPD overlap (ACO) has been used to identify a heterogeneous condition in which patients present with airflow limitation that is not completely reversible and clinical and inflammatory features of both asthma and chronic obstructive pulmonary disease (COPD). ACO diagnosis may be difficult in clinical practice, while controversy still exists regarding its definition, pathophysiology, and impact. Patients with ACO experience a greater disease burden compared to patients with asthma or COPD alone, but in contrast they show better response to inhaled corticosteroid treatment than other COPD phenotypes. Current management recommendations focus on defining specific and measurable treatable clinical traits, according to disease phenotypes and underlying biological mechanisms for every single patient. In this publication, we review the current knowledge on definition, pathophysiology, clinical characteristics, and management options of ACO. [ABSTRACT FROM AUTHOR]

The impaired production of extracellular matrix (ECM) proteins by airway smooth muscle cells (ASMC) and pulmonary fibroblasts (PF) is a part of airway remodeling in asthma. This process might be influenced by eosinophils that migrate to the airway and abundantly secrete various cytokines, including TGF-β. We aimed to investigate the effect of asthmatic eosinophils on the gene expression of ECM proteins in ASMC and PF. A total of 34 study subjects were recruited: 14 with allergic asthma (AA), 9 with severe non-allergic eosinophilic asthma (SNEA), and 11 healthy subjects (HS). All AA patients underwent bronchial allergen challenge with D. pteronyssinus. The peripheral blood eosinophils were isolated using high-density centrifugation and magnetic separation. The individual cell cultures were made using hTERT ASMC and MRC-5 cell lines and the subjects' eosinophils. The gene expression of ECM and the TGF-β signaling pathway was analyzed using qRT-PCR. We found that asthmatic eosinophils significantly promoted collagen I, fibronectin, versican, tenascin C, decorin, vitronectin, periostin, vimentin, MMP-9, ADAM33, TIMP-1, and TIMP-2 gene expression in ASMC and collagen I, collagen III, fibronectin, elastin, decorin, MMP-2, and TIMP-2 gene expression in PF compared with the HS eosinophil effect. The asthmatic eosinophils significantly increased the gene expression of several canonical and non-canonical TGF-β signaling pathway components in ASMC and PF compared with the HS eosinophil effect. The allergen-activated AA and SNEA eosinophils had a greater effect on these changes. In conclusion, asthmatic eosinophils, especially SNEA and allergen-activated eosinophils, imbalanced the gene expression of ECM proteins and their degradation-regulating proteins. These changes were associated with increased gene expression of TGF-β signaling pathway molecules in ASMC and PF. [ABSTRACT FROM AUTHOR]

Asthma is a complex disease of airways, where the interactions of immune and structural cells result in disease outcomes with airway remodeling and airway hyper-responsiveness. Polyamines, which are small-sized, natural super-cations, interactwith negatively charged intracellular macromolecules, and altered levels of polyamines and their interactions have been associated with different pathological conditions including asthma. Elevated levels of polyamines have been reported in the circulation of asthmatic patients as well as in the lungs of a murine model of asthma. In various studies, polyamines were found to potentiate the pathogenic potential of inflammatory cells, such as mast cells and granulocytes (eosinophils and neutrophils), by either inducing the release of their pro-inflammatory mediators or prolonging their life span. Additionally, polyamines were crucial in the differentiation and alternative activation of macrophages, which play an important role in asthma pathology. Importantly, polyamines cause airway smooth muscle contraction and thus airway hyper-responsiveness, which is the key feature in asthma pathophysiology. High levels of polyamines in asthma and their active cellular and macromolecular interactions indicate the importance of the polyamine pathway in asthma pathogenesis; therefore, modulation of polyamine levels could be a suitable approach in acute and severe asthma management. This review summarizes the possible roles of polyamines in different pathophysiological features of asthma. [ABSTRACT FROM AUTHOR]

Airway wall remodeling is a pathology occurring in chronic inflammatory lung diseases including asthma, chronic obstructive pulmonary disease, and fibrosis. In 2017, the American Thoracic Society released a research statement highlighting the gaps in knowledge and understanding of airway wall remodeling. The four major challenges addressed in this statement were: (i) the lack of consensus to define "airway wall remodeling" in different diseases, (ii) methodologic limitations and inappropriate models, (iii) the lack of anti-remodeling therapies, and (iv) the difficulty to define endpoints and outcomes in relevant studies. This review focuses on the importance of cell-cell interaction, especially the bronchial epithelium, in asthma-associated airway wall remodeling. The pathology of "airway wall remodeling" summarizes all structural changes of the airway wall without differentiating between different pheno- or endo-types of asthma. Indicators of airway wall remodeling have been reported in childhood asthma in the absence of any sign of inflammation; thus, the initiation event remains unknown. Recent studies have implied that the interaction between the epithelium with immune cells and sub-epithelial mesenchymal cells is modified in asthma by a yet unknown epigenetic mechanism during early childhood. [ABSTRACT FROM AUTHOR]

Hepatitis B Virus (HBV) is an Old World virus with a high mutation rate, which puts its origins in Africa alongside the origins of Homo sapiens, and is a member of the Hepadnaviridae family that is characterized by a unique viral replication cycle. It targets human hepatocytes and can lead to chronic HBV infection either after acute infection via horizontal transmission usually during infancy or childhood or via maternal–fetal transmission. HBV has been found in ~85% of HBV-related Hepatocellular Carcinomas (HCC), and it can integrate the whole or part of its genome into the host genomic DNA. The molecular mechanisms involved in the HBV DNA integration is not yet clear; thus, multiple models have been described with respect to either the relaxed-circular DNA (rcDNA) or the double-stranded linear DNA (dslDNA) of HBV. Various genes have been found to be affected by HBV DNA integration, including cell-proliferation-related genes, oncogenes and long non-coding RNA genes (lincRNAs). The present review summarizes the advances in the research of HBV DNA integration, focusing on the evolutionary and molecular side of the integration events along with the arising clinical aspects in the light of WHO's commitment to eliminate HBV and viral hepatitis by 2030. [ABSTRACT FROM AUTHOR]

Background: Asthma is a chronic inflammatory condition linked to hyperresponsiveness in the airways. There is currently no cure available for asthma, and therapy choices are limited. Asthma is the result of the interplay between genes and the environment. The exact molecular genetic mechanism of asthma remains elusive. Aims: The aim of this study is to provide a comprehensive, detailed molecular etiology profile for the molecular factors that regulate the severity of asthma and pathogenicity using integrative bioinformatics tools. Methods: The GSE43696 omnibus gene expression dataset, which contains 50 moderate cases, 38 severe cases, and 20 healthy controls, was used to investigate differentially expressed genes (DEGs), susceptible chromosomal loci, gene networks, pathways, gene ontologies, and protein–protein interactions (PPIs) using an intensive bioinformatics pipeline. Results: The PPI network analysis yielded DEGs that contribute to interactions that differ from moderate-to-severe asthma. The combined interaction scores resulted in higher interactions for the genes STAT3, AGO2, COL1A1, CLCN6, and KSR for moderate asthma and JAK2, INSR, ERBB2, NR3C1, and PTK6 for severe asthma. Enrichment analysis (EA) demonstrated differential enrichment between moderate and severe asthma phenotypes; the ion transport regulation pathway was significantly enhanced in severe asthma phenotypes compared to that in moderate asthma phenotypes and involved PER2, GCR, IRS-2, KCNK7, KCNK6, NOX1, and SCN7A. The most enriched common pathway in both moderate and severe asthma is the development of the glucocorticoid receptor (GR) signaling pathway followed by glucocorticoid-mediated inhibition of proinflammatory and proconstrictory signaling in the airway of smooth muscle cell pathways. Gene sets were shared between severe and moderate asthma at 16 chromosome locations, including 17p13.1, 16p11.2, 17q21.31, 1p36, and 19q13.2, while 60 and 48 chromosomal locations were unique for both moderate and severe asthma, respectively. Phylogenetic analysis for DEGs showed that several genes have been intersected in phases of asthma in the same cluster of genes. This could indicate that several asthma-associated genes have a common ancestor and could be linked to the same biological function or gene family, implying the importance of these genes in the pathogenesis of asthma. Conclusion: New genetic risk factors for the development of moderate-to-severe asthma were identified in this study, and these could provide a better understanding of the molecular pathology of asthma and might provide a platform for the treatment of asthma. [ABSTRACT FROM AUTHOR]

The intrauterine environment may be related to the future development of chronic diseases in the offspring. The St. Carlos gestational diabetes mellitus (GDM) prevention study, is a randomized controlled trial that evaluated the influence of the early (before 12th gestational week) Mediterranean diet (MedDiet) on the onset of GDM and adverse gestational outcomes. Out of 874 women assessed after delivery (440 control group (CG)/434 intervention group (IG)), 703 children were followed (365/338; CG/IG), with the aim to assess whether the adherence to a MedDiet during pregnancy induces health benefits for the offspring during the first two years of life. Logistic regression analysis showed that the IG in children of mothers with pre-gestational body mass index (BMI) < 25 kg/m2 and normal glucose tolerance (NGT), was associated with a lower risk (RR(95% CI)) of suffering from severe events requiring hospitalization due to bronchiolitis/asthma (0.75(0.58–0.98) and 0.77(0.59–0.99), respectively) or other diseases that required either antibiotic (0.80(0.65–0.98) and 0.80(0.65–0.99), respectively), corticosteroid treatment (0.73(0.59–0.90) and 0.79(0.62–1.00) respectively) or both (all p < 0.05). A nutritional intervention based on the MedDiet during pregnancy is associated with a reduction in offspring's hospital admissions, especially in women with pre-gestational BMI < 25 kg/m2 and NGT. [ABSTRACT FROM AUTHOR]

Eosinophils infiltration and releasing TGF-β1 in the airways has been implicated in the pathogenesis of asthma, especially during acute episodes provoked by an allergen. TGF-β1 is a major mediator involved in pro-inflammatory responses and fibrotic tissue remodeling in asthma. We aimed to evaluate the effect of in vivo allergen-activated eosinophils on the expression of COL1A1 and FN in ASM cells in asthma. A total of 12 allergic asthma patients and 11 healthy subjects were examined. All study subjects underwent bronchial challenge with D. pteronyssinus allergen. Eosinophils from peripheral blood were isolated before and 24 h after the bronchial allergen challenge using high-density centrifugation and magnetic separation. Individual co-cultures of blood eosinophils and immortalized human ASM cells were prepared. The TGF-β1 concentration in culture supernatants was analyzed using ELISA. Gene expression was analyzed using qRT-PCR. Eosinophils integrins were suppressed with linear RGDS peptide before co-culture with ASM cells. Results: The expression of TGF-β1 in asthmatic eosinophils significantly increased over non-activated asthmatic eosinophils after allergen challenge, p < 0.001. The TGF-β1 concentration in culture supernatants was significantly higher in samples with allergen-activated asthmatic eosinophils compared to baseline, p < 0.05. The effect of allergen-activated asthmatic eosinophils on the expression of TGF-β1, COL1A1, and FN in ASM cells was more significant compared to non-activated eosinophils, p < 0.05, however, no difference was found on WNT-5A expression. The incubation of allergen-activated asthmatic eosinophils with RGDS peptide was more effective compared to non-activated eosinophils as the gene expression in ASM cells was downregulated equally to the same level as healthy eosinophils. [ABSTRACT FROM AUTHOR]

Asthma increases worldwide without any definite reason and patient numbers double every 10 years. Drugs used for asthma therapy relax the muscles and reduce inflammation, but none of them inhibited airway wall remodeling in clinical studies. Airway wall remodeling can either be induced through pro-inflammatory cytokines released by immune cells, or direct binding of IgE to smooth muscle cells, or non-immunological stimuli. Increasing evidence suggests that airway wall remodeling is initiated early in life by epigenetic events that lead to cell type specific pathologies, and modulate the interaction between epithelial and sub-epithelial cells. Animal models are only available for remodeling in allergic asthma, but none for non-allergic asthma. In human asthma, the mechanisms leading to airway wall remodeling are not well understood. In order to improve the understanding of this asthma pathology, the definition of "remodeling" needs to be better specified as it summarizes a wide range of tissue structural changes. Second, it needs to be assessed if specific remodeling patterns occur in specific asthma pheno- or endo-types. Third, the interaction of the immune cells with tissue forming cells needs to be assessed in both directions; e.g., do immune cells always stimulate tissue cells or are inflamed tissue cells calling immune cells to the rescue? This review aims to provide an overview on immunologic and non-immunologic mechanisms controlling airway wall remodeling in asthma. [ABSTRACT FROM AUTHOR]

Asthma is characterized by airway inflammation and remodeling. 2-Undecanone (methyl nonyl ketone), a volatile organic compound originating from Houttuynia cordata, has the potential to ameliorate inflammatory diseases. This study aimed to explore potential benefits of 2-undecanone in asthma. 2-Undecanone (100, 200, or 400 mg/kg) was administered intragastrically to ovalbumin (OVA)-challenged BALB/c mice. Lung tissues were collected to observe histopathological changes, and bronchoalveolar lavage fluid (BALF) was collected for the detection of inflammatory cells and cytokine production. The results showed that 2-undecanone ameliorated OVA-induced pathologic changes of lungs, including reducing inflammatory cell infiltration, goblet cell hyperplasia, and airway smooth muscle thickness. The number of inflammatory cells and the levels of IL-4, IL-5, IL-13, and IgE in BALF were decreased by 2-undecanone in asthmatic mice. Furthermore, abnormal activation of NF-[kappa]B pathway in lung tissues of asthmatic mice was impeded by 2-undecanone. In vitro, 2-undecanone (12.5, 25, or 50 [micro]M) suppressed platelet-derived growth factor-BB-induced proliferation and migration of primary airway smooth muscle cells (ASMCs), and inhibited the switching of ASMCs from contractile phenotype to synthetic phenotype. Consistently, 2-undecanone blocked NF-[kappa]B activation in ASMCs. Collectively, 2-undecanone relieves asthma through alleviating airway inflammation and remodeling, and this beneficial effect is achieved by inhibiting NF-[kappa]B pathway. Key words: asthma, 2-undecanone, NF-[kappa]B pathway, airway inflammation, airway remodeling, Introduction Asthma is a common chronic respiratory disease characterized by reversible and intermittent airflow obstruction, airway hyperresponsiveness, airway remodeling, and chronic inflammation (Barcik et al. 2020; Schoettler and Strek 2020). [...]

The mechanisms whereby anticholinergics improve asthma outcomes, such as lung function, symptoms, and rate of exacerbation, can be numerous. The most obvious is by affecting the contraction of airway smooth muscle (ASM). The acetylcholine released from the cholinergic nerves is the most important bronchoconstrictor that sets the baseline degree of contractile activation of ASM in healthy individuals. Although the degree of ASM's contractile activation can also be fine-tuned by a plethora of other bronchoconstrictors and bronchodilators in asthma, blocking the ceaseless effect of acetylcholine on ASM by anticholinergics reduces, at any given moment, the overall degree of contractile activation. Because the relationships that exist between the degree of contractile activation, ASM force, ASM shortening, airway narrowing, airflow resistance, and respiratory resistance are not linear, small decreases in the contractile activation of ASM can be greatly amplified and thus translate into important benefits to a patient's well-being. Plus, many inflammatory and remodeling features that are often found in asthmatic lungs synergize with the contractile activation of ASM to increase respiratory resistance. This review recalls that the proven effectiveness of anticholinergics in the treatment of asthma could be merely attributed to a small reduction in the contractile activation of ASM. Key words: long-acting muscarinic antagonists, airway smooth muscle, airway narrowing, airway hyperresponsiveness, respiratory resistance. Les modes d'action par lesquels les anticholinergiques ameliorent l'asthme--sur le plan de la fonction pulmonaire, des symptomes et de la frequence des exacerbations--peuvent etre nombreux. Le plus evident constitue les effets sur la contraction du muscle lisse des voies aeriennes (MLVA). L'acetylcholine liberee des nerfs cholinergiques represente le plus important bronchoconstricteur dans l'etablissement du niveau de base de l'activation contractile du MLVA chez des personnes en bonne sante. Meme si le degre d'activation contractile du MLVA peut aussi etre regle finement par une plethore d'autres bronchocontricteurs et bronchodilatateurs dans l'asthme, l'inhibition des effets incessants de l'acetylcholine sur le MLVA a l'aide d'anticholinergiques permet de reduire, en tout temps, le degre total d'activation contractile. Puisque les relations qui existent entre le degre d'activation contractile, la force du MLVA, le raccourcissement des cellules du MLVA, le retrecissement des voies aeriennes, la resistance au debit d'air et la resistance pulmonaire ne sont pas lineaires, de petites diminutions de l'activation contractile du MLVA peuvent etre amplifiees de facon tres marquee et donc se traduire par des avantages importants sur le plan du bien-etre du patient. En plus, de nombreuses caracteristiques de l'inflammation et du remodelage, que l'on retrouve souvent dans les poumons de patients atteints d'asthme, entrent en synergie avec l'activation contractile du MLVA afin d'augmenter la resistance pulmonaire. Cet article de synthese rappelle que l'efficacite averee des anticholinergiques dans le traitement de l'asthme pourrait etre simplement attribuable a une faible reduction de l'activation contractile du MLVA. [Traduit par la Redaction] Mots-cles : antagonistes muscariniques a longue duree d'action, muscle lisse des voies aeriennes, retrecissement des voies aeriennes, hyperreactivite des voies aeriennes, resistance pulmonaire., Introduction The symptoms of asthma are either persistent or episodic and generally coincide with perennial or time-varying exposure to environmental factor(s). The diagnosis of asthma is usually straightforward as it [...]

Airway smooth muscle (ASM) plays a central role in the excessive narrowing of the airway that characterizes the primary functional impairment in asthma. This phenomenon is known as airway hyper-responsiveness (AHR). Emerging evidence suggests that the development and maintenance of ASM force involves dynamic reorganization of the subcellular filament network in both the cytoskeleton and the contractile apparatus. In this review, evidence is presented to support the view that regulation of ASM contraction extends beyond the classical actomyosin interaction and involves processes within the cytoskeleton and at the interfaces between the cytoskeleton, the contractile apparatus, and the extracellular matrix. These processes are initiated when the muscle is activated, and collectively they cause the cytoskeleton and the contractile apparatus to undergo structural transformation, resulting in a more connected and solid state that allows force generated by the contractile apparatus to be transmitted to the extracellular domain. Solidification of the cytoskeleton also serves to stiffen the muscle and hence the airway. Oscillatory strain from tidal breathing and deep inspiration is believed to be the counter balance that prevents hypercontraction and stiffening of ASM in vivo. Dysregulation of this balance could lead to AHR seen in asthma. Key words: asthma, Rho-kinase, cytoskeleton, cross-bridge, length adaptation, force adaptation. Le muscle lisse respiratoire (MLR) joue un role central dans le retrecissement excessif des voies respiratoires qui caracterise la principale deterioration fonctionnelle associee a l'asthme. Ce phenomene est connu sous le nom d'hyperreactivite bronchique (HRB). Une donnee nouvelle suggere que le developpement et le maintien de la force du MLR implique la reorganization dynamique du reseau de filaments subcellulaires du cytosquelette et de l'appareil contractile. Dans cet article de revue, les auteurs presentent une preuve qui appuie la vision que la contraction du MLR va au-dela de l'interaction classique de l'actomyosine et implique des processus a l'interieur du cytosquelette et a l'interface entre le cytosquelette, l'appareil contractile et la matrice extracellulaire. Ces processus sont inities lorsque le muscle est active, et ils provoquent collectivement une transformation structurale du cytosquelette et de l'appareil contractile resultant en un etat mieux connecte et solide qui permet a la force generee par l'appareil contractile de se transmettre au domaine extracellulaire. La solidification du cytosquelette sert aussi a durcir le muscle et, consequemment, les voies respiratoires. On croit que la pression oscillatoire de la respiration courante et de l'inspiration profonde constitue la contrebalance qui previent l'hyper-contraction et le durcissement du MLR in vivo. La deregulation de cette balance pourrait conduire a l'HRB observee dans l'asthme. [Traduit par la Redaction] Mots-cles: asthme, Rho-kinase, cytosquelette, ponts transversaux, adaptation de la longueur, adaptation de la force., Introduction The regulation of the mechanical properties of smooth muscle, such as the ability to generate force and maintain tensile stiffness, is fundamental to the proper functioning of the muscle. [...]

It has long been known that airway smooth muscle (ASM) contraction contributes significantly to the reversible airflow obstruction that defines asthma. It has also been postulated that phenotypic changes in ASM contribute to the airway hyperresponsiveness (AHR) that is a characteristic feature of asthma. Although there is agreement that the mass of ASM surrounding the airways is significantly increased in asthmatic compared with non-asthmatic airways, it is still uncertain whether there are quantitative or qualitative changes in the level of expression of the genes and proteins involved in the canonical contractile pathway in ASM that could account for AHR. This review will summarize past attempts at quantifying gene expression changes in the ASM of asthmatic lungs as well as non-asthmatic ASM cells stimulated with various inflammatory cytokines. The lack of consistent findings in asthmatic samples coupled with the relative concordance of results from stimulated ASM cells suggests that changes to the contractility of ASM tissues in asthma may be dependent on the presence of an inflammatory environment surrounding the ASM layer. Removal of the ASM from this environment could explain why hypercontractility is rarely seen ex vivo. Key words: asthma, airway smooth muscle, gene expression, protein expression, cytokines. On sait depuis longtemps que la contraction du muscle lisse respiratoire (MLR) contribue de maniere significative a l'obstruction reversible du debit d'air qui definit l'asthme. Il a aussi ete postule que des changements phenotypiques dans le MLR contribue a l'hyperreactivite bronchique (HRB) qui caracterise l'asthme. Meme si l'on s'accorde sur le fait que la masse de MLR qui entoure les voies respiratoires est significativement plus importante en situation d'asthme comparativement a l'absence d'asthme, on ne sait pas encore avec certitude si des changements quantitatifs ou qualitatifs du niveau d'expression de genes et de proteines impliques dans les voies standards de regulation de la contraction chez le MLR pourraient expliquer l'HRB. Cet article de revue resumera les tentatives passees de quantification de changements d'expression genique dans des cellules de MLR de poumons asthmatiques et non asthmatiques, stimulees a l'aide de differentes cytokines inflammatoires. L'absence de donnees coherentes issues d'echantillons asthmatiques, couplee a la concordance relative des resultats obtenus a partir de cellules de MLR stimulees suggere que les changements de contractilite du MLR dans l'asthme peuvent etre dependants de la presence d'un environnement inflammatoire autour de la couche de MLR. Le fait de retirer le MLR de son environnement pourrait expliquer pourquoi l'hyper-contractilite est rarement observee ex vivo. [Traduit par la Redaction] Mots-cles: asthme, muscle lisse respiratoire, expression genique, expression proteique, cytokines., Introduction Asthma is a disease that affects nearly 300 million people worldwide (Masoli et al. 2004) and is characterized by periods of breathlessness and wheezing caused by narrowing of the [...]

Airway inflammation is a key aspect of diseases such as asthma. Several inflammatory cytokines (e.g., TNFα and IL-13) increase cytosolic [Ca.sup.2+] ([[[Ca.sup.2+]].sub.cyt]) responses to agonist stimulation and [Ca.sup.2+] sensitivity of force generation, thereby enhancing airway smooth muscle (ASM) contractility (hyper-reactive state). Inflammation also induces ASM proliferation and remodeling (synthetic state). In normal ASM, the transient elevation of [[[Ca.sup.2+]].sub.cyt] induced by agonists leads to a transient increase in mitochondrial [Ca.sup.2+] ([[[Ca.sup.2+]].sub.mito]) that may be important in matching ATP production with ATP consumption. In human ASM (hASM) exposed to TNFα and IL-13, the transient increase in [[[Ca.sup.2+]].sub.mito] is blunted despite enhanced [[[Ca.sup.2+]].sub.cyt] responses. We also found that TNFα and IL-13 induce reactive oxidant species (ROS) formation and endoplasmic/sarcoplasmic reticulum (ER/SR) stress (unfolded protein response) in hASM. ER/SR stress in hASM is associated with disruption of mitochondrial coupling with the ER/SR membrane, which relates to reduced mitofusin 2 (Mfn2) expression. Thus, in hASM it appears that TNFα and IL-13 result in ROS formation leading to ER/SR stress, reduced Mfn2 expression, disruption of mitochondrion-ER/SR coupling, decreased mitochondrial [Ca.sup.2+] buffering, mitochondrial fragmentation, and increased cell proliferation. Key words: inflammation, ER/SR stress, airway, asthma, unfolded protein response. L'inflammation de voies respiratoires est un aspect cle de maladies comme l'asthme. Plusieurs cytokines inflammatoires (ex. TNFα et IL-13) augmentent le [Ca.sup.2+] cytosolique ([[[Ca.sup.2+]].sub.cyt]) en reponse a une stimulation par un agoniste et la sensibilite de la generation de forces au calcium, augmentant ainsi la contractilite du muscle lisse respiratoire (MLR) (etat d'hyperreactivite). L'inflammation induit aussi la proliferation et le remodelage des cellules du MLR (etat de synthese). Chez le MLR, l'elevation transitoire de [[[Ca.sup.2+]].sub.cyt] induite par un agoniste mene a une augmentation transitoire du [Ca.sup.2+] mitochondrial ([[[Ca.sup.2+]].sub.mito]) qui peut etre importante pour arrimer la production d'ATP a sa consommation. Chez les cellules de MLR humain (hMLR) exposees au TNFα et a l'IL-13, l'augmentation transitoire de [[[Ca.sup.2+]].sub.mito] est attenuee malgre l'augmentation de [[[Ca.sup.2+]].sub.cyt]. Les auteurs trouvent aussi que le TNFα et l'IL-13 induisent la formation d'especes reactives d'oxygene (ERO) et un stress du reticulum endoplasmique/ sarcoplasmique (RE/RS) (reponse aux proteines depliees) chez les hMLR. Le stress RE/RS chez les hMLR est associe au decouplage de la mitochondrie a la membrane du RE/RS, phenomene relie a la reduction de l'expression de la mitofusine 2 (Mfn2). Ainsi, chez les hMLR, il semble que le TNFα et l'IL-13 induisent la formation d'ERO conduisant a un stress du RE/RS, a la reduction de l'expression de Mfn2, au decouplage de la mitochondrie au RE/RS, a la diminution du tamponnage du [Ca.sup.2+] mitochondrial, a la fragmentation mitochondriale et a l'augmentation de la proliferation cellulaire. [Traduit par la Redaction] Mots-cles: inflammation, stress du RE/RS, voies respiratoires, asthme, reponse aux proteines depliees., Introduction Asthma affects more than 20 million people in the USA (~10% of the population), and more than 300 million people world-wide (GINA 2012). It is now recognized that inflammation [...]

The standard method for measuring the phosphorylation of the regulatory myosin light chain (MLC20) in smooth muscle is extraction of the light chain using a urea extraction buffer, urea-glycerol gel electrophoresis of the soluble portion of the extract (supernatant) and Western blot analysis. The undissolved portion of the tissue during extraction (the pellet) is usually discarded. Because the pellet contains a finite amount of MLC20, omission of the pellet could result in inaccurate measurement of MLC20 phosphorylation. In this study we compared the level of tracheal smooth muscle MLC20 phosphorylation in the supernatant alone, with that in the complete tissue homogenate (supernatant and pellet) using the standard method. The supernatant fraction showed the well-known double bands representing phosphorylated and un-phosphorylated MLC20. The dissolved pellet fraction showed varying amounts of un-phosphorylated and phosphorylated MLC20. There was a small but statistically significant overestimation of the percent MLC20 phosphorylation if the pellet was not taken into consideration. The overestimation was 7% ± 2% (mean ± SEM) (p < 0.05) in unstimulated muscle and 2% ± 1% (p < 0.05) in acetylcholine (10-6 mol/L) stimulated muscle. This finding suggests that for accurate estimation of the stoichiometry of MLC20 phosphorylation it is necessary to consider the contribution from the pellet portion of the muscle tissue homogenate. Key words: urea-glycerol gel electrophoresis, MLC20 phosphorylation, supernatant and pellet, Western blots. La methode standard pour mesurer la phosphorylation de la chaine legere de la myosine regulatrice (MLC20) dans le muscle lisse consiste en une extraction de la chaine legere dans un tampon d'extraction comprenant de l'uree, une electrophorese sur gel d'uree-glycerol de la portion soluble de l'extrait (surnageant) et d'un buvardage Western. La portion tissulaire non dissoute lors de l'extraction (culot) est habituellement jetee. Parce que le culot contient une faible quantite de MLC20, l'omission du culot pourrait resulter en une mesure imprecise de la phosphorylation de la MLC20. Dans cette etude, les auteurs ont compare le niveau de phosphorylation de MLC20 du muscle lisse tracheal dans le surnageant seul a celui de l'homogenat tissulaire complet (surnageant et culot) a l'aide de la methode standard. La fraction du surnageant montrait les doubles bandes bien connues representant la MLC20 phosphorylee et non phosphorylee. La fraction dissoute du culot contenait des quantites variables de MLC20 phosphorylee et non phosphorylee. Il y avait une legere mais significative surestimation du pourcentage de MLC20 phosphorylee si le culot n'etait pas considere. La surestimation etait de7%±2% (moyenne ± ESM) (p < 0,05) dans le muscle non stimule et de 2%[+ or -]1%(p < 0,05) dans le muscle stimule a l'acetylcholine (10-6 mol/L). Ces donnees suggerent que l'estimation precise de la strechiometrie de la phosphorylation de la MLC20 necessite de considerer la contribution de la portion du culot issue de l'homogenat de tissu musculaire. [Traduit par la Redaction] Mots-cles: electrophorese sur gel uree-glycerol, phosphorylation de la MLC20, surnageant et culot, buvardages Western., Introduction The crucial step for the initiation of the ATP-dependent actomyosin interaction in smooth muscle is the phosphorylation of the myosin light chain 20 (MLC20) (Frearson et al. 1976; Sobieszek [...]