Daniel Sastre, Magali Colomer-Molera, Sara R Roig, Angela de Benito-Bueno, Paula G Socuellamos, Gregorio Fernandez-Ballester, Carmen Valenzuela, Antonio Felipe
{"title":"Molecular mapping of KCNE4-dependent regulation of Kv1.3.","authors":"Daniel Sastre, Magali Colomer-Molera, Sara R Roig, Angela de Benito-Bueno, Paula G Socuellamos, Gregorio Fernandez-Ballester, Carmen Valenzuela, Antonio Felipe","doi":"10.1152/ajpcell.00499.2024","DOIUrl":"https://doi.org/10.1152/ajpcell.00499.2024","url":null,"abstract":"<p><p>The voltage-gated potassium channel Kv1.3 plays a crucial role in the immune system response. In leukocytes, the channel is coexpressed with the dominant negative regulatory subunit KCNE4, which associates with Kv1.3 to trigger intracellular retention and accelerating C-type inactivation of the channel. Previous research has demonstrated that the main association between these proteins occurs through both C-termini. However, these data fail to fully elucidate the KCNE4-dependent modulation of channel kinetics. In the present study, we analyzed the contribution of each KCNE4 domain to the modulation of Kv1.3. Our results further confirmed that the C-terminus of KCNE4 is the main determinant involved in the association-triggered intracellular retention of the channel. Moreover, interactions throughout the transmembrane region were also observed. Both the C-terminus and, especially, the transmembrane domain of KCNE4 accentuated the C-type inactivation of Kv1.3. Our data provide, for the first time, the molecular effects that a KCNE peptide, such as KCNE4, exerts on a <i>Shaker</i> channel, such as Kv1.3. Our results pave the way for understanding the molecular mechanisms underlying potassium channel modulation and suggest that KCNE4 participates in the conformational rearrangement of the Kv1.3 architecture, altering the C-type inactivation of the channel.</p>","PeriodicalId":7585,"journal":{"name":"American journal of physiology. Cell physiology","volume":" ","pages":""},"PeriodicalIF":5.0,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142492909","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"ITGA3 participates in the pathogenesis of recurrent spontaneous abortion by downregulating ULK1-mediated autophagy to inhibiting trophoblast function.","authors":"Rui Qi Wang, Fangfang Dai, Zhimin Deng, Lujia Tang, Hua Liu, Liangbin Xia, Yanxiang Cheng","doi":"10.1152/ajpcell.00563.2024","DOIUrl":"https://doi.org/10.1152/ajpcell.00563.2024","url":null,"abstract":"<p><p>Recurrent spontaneous abortion (RSA) is a significant challenge encountered by couples of reproductive ages, with inadequate trophoblast invasion identified as a primary factor in RSA pathogenesis. However, the precise molecular mechanisms through which trophoblast cells dysfunction leads to RSA remain incompletely understood. Research has highlighted the critical role of integrins in embryo implantation and development. While integrin α-3 (ITGA3) is recognized for its promotion of invasion in cancer cells, its involvement in miscarriage remains poorly characterized. This investigation initially assessed ITGA3 expression in villous tissues obtained from RSA patients and induced abortion patients. The findings demonstrated a notable reduction in ITGA3 levels in the villous tissues of RSA patients compared control group. Subsequent in vitro analyses indicated that ITGA3 knockdown inhibited the migration, invasion, and proliferation of trophoblast cells. Through RNA sequencing and subsequent experimentation, it was revealed that ITGA3 regulated ULK1-mediated autophagy to influence trophoblast cells invasion, migration, and proliferation. Furthermore, utilizing a miscarriage animal model, the diminished expression of ITGA3 and ULK1 in the placentas of RSA mice was confirmed. In conclusion, the study findings suggest that the downregulation of ITGA3 suppresses ULK1 expression, consequently impeding autophagy to initiation and impeding trophoblast cells invasion and migration, thereby contributing to the pathological progression of RSA.</p>","PeriodicalId":7585,"journal":{"name":"American journal of physiology. Cell physiology","volume":" ","pages":""},"PeriodicalIF":5.0,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142492908","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lisa Hahnefeld, Juliane Hackel, Sandra Trautmann, Carlo Angioni, Yannick Schreiber, Robert Gurke, Dominique Thomas, Sabine Wicker, Gerd Geisslinger, Irmgard Tegeder
{"title":"Healthy plasma lipidomic signatures depend on sex, age, body mass index, and contraceptives but not perceived stress.","authors":"Lisa Hahnefeld, Juliane Hackel, Sandra Trautmann, Carlo Angioni, Yannick Schreiber, Robert Gurke, Dominique Thomas, Sabine Wicker, Gerd Geisslinger, Irmgard Tegeder","doi":"10.1152/ajpcell.00630.2024","DOIUrl":"https://doi.org/10.1152/ajpcell.00630.2024","url":null,"abstract":"<p><p>Perceived stress is thought to contribute to the pathogenesis of metabolic, vascular, mental, and immune diseases, with different susceptibilities in women and men. The present study investigated if and how perceived stress and/or demographic variables including sex, age, body mass index, regular prescription drugs, occasional analgesics, or dietary supplements manifested in plasma lipidomic profiles, obtained by targeted and untargeted mass spectrometry analyses. The study included 217 healthy women and 108 healthy men, aged 18-68 years, who were recruited in a 2:1 female:male ratio to account for women with/without contraceptives. As expected, dehydroepiandrosterone sulfate (DHEAS) and ceramides were higher in men than women, and DHEAS decreased with age, while ceramides increased. Contrary to expectations, neither DHEAS nor ceramides were associated with perceived stress (PSQ30 questionnaire), which was however, associated with BMI in men, but not in women. None of the lipid species or classes showed a similar \"age X sex X BMI\" interaction, but the endocannabinoid palmitoylethanolamide (PEA) correlated with BMI and hypertension. Independent of perceived stress, lysophosphatidylcholines (LPCs) were lower in women than men, whereas LPC metabolites, lysophosphatidic acids (LPAs), were higher in women. The LPA:LPC ratio was particularly high in women using oral contraceptives suggesting a strong hormone-induced extracellular conversion of LPCs to LPAs, which is catalyzed by the phospholipase D, autotaxin. The results reveal complex sex differences in perceived stress and lipidomic profiles, the latter being exacerbated by contraceptive use, but perceived stress and lipids were not directly correlated.</p>","PeriodicalId":7585,"journal":{"name":"American journal of physiology. Cell physiology","volume":" ","pages":""},"PeriodicalIF":5.0,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142492906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"TFEB signaling promotes autophagic degradation of NLRP3 to attenuate neuroinflammation in diabetic encephalopathy.","authors":"Yijia Lin, Lizhen Cheng, Yixin Chen, Wei Li, Qihao Guo, Ya Miao","doi":"10.1152/ajpcell.00322.2024","DOIUrl":"https://doi.org/10.1152/ajpcell.00322.2024","url":null,"abstract":"<p><p>Diabetic encephalopathy (DE), a neurological complication of diabetes mellitus, has an unclear etiology. Shreds of evidence show that the Nucleotide-binding oligomerization domain-like receptor family protein 3 (NLRP3) inflammasome-induced neuroinflammation and transcription factor EB (TFEB)-mediated autophagy impairment may take part in DE development. The crosstalk between these two pathways and their contribution to DE remains to be explored. A mouse model of type 2 diabetes mellitus (T2DM) exhibiting cognitive dysfunction was created, along with high glucose (HG) cultured BV2 cells. Following, 3-methyladenine (3-MA) and rapamycin were utilized to modulate autophagy. To evaluate the potential therapeutic benefits of TFEB in DE, we overexpressed and knocked down TFEB in both mice and cells. Autophagy impairment and NLRP3 inflammasome activation were noticed in T2DM mice and HG-cultured BV2 cells. The inflammatory response caused by NLRP3 inflammasome activation was decreased by rapamycin-induced autophagy enhancement, while 3-MA treatment further deteriorated it. Nuclear translocation and expression of TFEB were hampered in HG-cultured BV2 cells and T2DM mice. Exogenous TFEB overexpression boosted NLRP3 degradation via autophagy, which in turn alleviated microglial activation as well as ameliorated cognitive deficits and neuronal damage. Additionally, TFEB knockdown exacerbated neuroinflammation by decreasing autophagy-mediated NLRP3 degradation. Our findings have unraveled the pathogenesis of a previously underappreciated disease, implying that the activation of NLRP3 inflammasome and impairment of autophagy in microglia are significant etiological factors in the DE. The TFEB-mediated autophagy pathway can reduce neuroinflammation by enhancing NLRP3 degradation. This could potentially serve as a viable and innovative treatment approach for DE.</p>","PeriodicalId":7585,"journal":{"name":"American journal of physiology. Cell physiology","volume":" ","pages":""},"PeriodicalIF":5.0,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142492911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"5-Aminoimidazole-4-carboxamide ribonucleotide formyltransferase/inosine monophosphate cyclohydrolase promotes pulmonary arterial smooth muscle cell proliferation via the Ras signaling pathway.","authors":"Xiaofan Shi, Qian Ma, Yuqing Huo, Yunchao Su","doi":"10.1152/ajpcell.00262.2024","DOIUrl":"10.1152/ajpcell.00262.2024","url":null,"abstract":"<p><p>Pulmonary arterial hypertension (PAH) is a debilitating vascular disorder characterized by abnormal pulmonary artery smooth muscle cell (PASMC) proliferation and collagen synthesis, contributing to vascular remodeling and elevated pulmonary vascular resistance. This study investigated the critical role of 5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase/inosine monophosphate cyclohydrolase (ATIC) in cell proliferation and collagen synthesis in PASMCs in PAH. Here we show that ATIC levels are significantly increased in the lungs of monocrotaline (MCT)-induced PAH rat model, hypoxia-induced PAH mouse model, and platelet-derived growth factor (PDGF)-stimulated PASMCs. Inhibition of ATIC attenuated PDGF-induced cell proliferation and collagen I synthesis in PASMCs. Conversely, overexpression or knockdown of ATIC causes a significant promotion or inhibition of Ras and ERK activation, cell proliferation, and collagen synthesis in PASMCs. Moreover, ATIC deficiency attenuated Ras activation in the lungs of hypoxia-induced PAH mice. Furthermore, Ras inhibition attenuates ATIC overexpression- and PDGF-induced collagen synthesis and PASMC proliferation. Notably, we identified that transcription factors MYC, early growth response protein 1 (EGR1), and specificity protein 1 (SP1) directly binds to promoters of <i>Atic</i> gene and regulate ATIC expression. These results provide the first evidence that ATIC promotes PASMC proliferation in pulmonary vascular remodeling through the Ras signaling pathway.<b>NEW & NOTEWORTHY</b> Our findings highlight the important role of ATIC in the PASMC proliferation of pulmonary vascular remodeling through its modulation of the Ras signaling pathway and its regulation by transcription factors MYC, EGR1, and SP1. ATIC's modulation of Ras signal pathway represents a novel mechanism contributing to PAH development.</p>","PeriodicalId":7585,"journal":{"name":"American journal of physiology. Cell physiology","volume":" ","pages":"C901-C912"},"PeriodicalIF":5.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11481986/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141915823","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
André L L Monteiro, Marcos Eliezeck, Sérgio R A Scalzo, Mário Morais Silva, Bruno Sanches, Katyana K S Ferreira, Maristela O Poletini, Rodrigo A Peliciari-Garcia, Stêfany B A Cau, Robson A Souza Santos, Silvia Guatimosim
{"title":"Time of day affects MrgD-dependent modulation of cardiomyocyte contractility.","authors":"André L L Monteiro, Marcos Eliezeck, Sérgio R A Scalzo, Mário Morais Silva, Bruno Sanches, Katyana K S Ferreira, Maristela O Poletini, Rodrigo A Peliciari-Garcia, Stêfany B A Cau, Robson A Souza Santos, Silvia Guatimosim","doi":"10.1152/ajpcell.00049.2024","DOIUrl":"10.1152/ajpcell.00049.2024","url":null,"abstract":"<p><p>The renin-angiotensin system (RAS) is composed of a series of peptides, receptors, and enzymes that play a pivotal role in maintaining cardiovascular homeostasis. Among the most important players in this system are the angiotensin-II and angiotensin-(1-7) peptides. Our group has recently demonstrated that alamandine (ALA), a peptide with structural and functional similarities to angiotensin-(1-7), interacts with cardiomyocytes, enhancing contractility via the Mas-related G protein-coupled receptor member D (MrgD). It is currently unknown whether this modulation varies along the distinct phases of the day. To address this issue, we assessed the ALA-induced contractility response of cardiomyocytes from mice at four Zeitgeber times (ZTs). At ZT2 (light phase), ALA enhanced cardiomyocyte shortening in an MrgD receptor-dependent manner, which was associated with nitric oxide (NO) production. At ZT14 (dark phase), ALA induced a negative modulation on the cardiomyocyte contraction. β-Alanine, an MrgD agonist, reproduced the time-of-day effects of ALA on myocyte shortening. <i>N</i><sup>G</sup>-nitro-l-arginine methyl ester, an NO synthase inhibitor, blocked the increase in fractional shortening induced by ALA at ZT2. No effect of ALA on myocyte shortening was observed at ZT8 and ZT20. Our results show that ALA/MrgD signaling in cardiomyocytes is subject to temporal modulation. This finding has significant implications for pharmacological approaches that combine chronotherapy for cardiac conditions triggered by disruption of circadian rhythms and hormonal signaling.<b>NEW & NOTEWORTHY</b> Alamandine, a member of the renin-angiotensin system, serves critical roles in cardioprotection, including the modulation of cardiomyocyte contractility. Whether this effect varies along the day is unknown. Our results provide evidence that alamandine via receptor MrgD exerts opposing actions on cardiomyocyte shortening, enhancing, or reducing contraction depending on the time of day. These findings may have significant implications for the development and effectiveness of future cardiac therapies.</p>","PeriodicalId":7585,"journal":{"name":"American journal of physiology. Cell physiology","volume":" ","pages":"C1143-C1149"},"PeriodicalIF":5.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142003396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lei Lei, Ting Zhu, Tian-Jiao Cui, Yvonne Liu, Johann-Georg Hocher, Xin Chen, Xue-Mei Zhang, Kai-Wen Cai, Zi-Yan Deng, Xiao-Hua Wang, Chun Tang, Lian Lin, Christoph Reichetzeder, Zhi-Hua Zheng, Berthold Hocher, Yong-Ping Lu
{"title":"Renoprotective effects of empagliflozin in high-fat diet-induced obesity-related glomerulopathy by regulation of gut-kidney axis.","authors":"Lei Lei, Ting Zhu, Tian-Jiao Cui, Yvonne Liu, Johann-Georg Hocher, Xin Chen, Xue-Mei Zhang, Kai-Wen Cai, Zi-Yan Deng, Xiao-Hua Wang, Chun Tang, Lian Lin, Christoph Reichetzeder, Zhi-Hua Zheng, Berthold Hocher, Yong-Ping Lu","doi":"10.1152/ajpcell.00367.2024","DOIUrl":"10.1152/ajpcell.00367.2024","url":null,"abstract":"<p><p>The increasing prevalence of obesity-related glomerulopathy (ORG) poses a significant threat to public health. Sodium-glucose cotransporter-2 (SGLT2) inhibitors effectively reduce body weight and total fat mass in individuals with obesity and halt the progression of ORG. However, the underlying mechanisms of their reno-protective effects in ORG remain unclear. We established a high-fat diet-induced ORG model using C57BL/6J mice, which were divided into three groups: normal chow diet (NCD group), high-fat diet (HFD) mice treated with placebo (ORG group), and HFD mice treated with empagliflozin (EMPA group). We conducted 16S ribosomal RNA gene sequencing of feces and analyzed metabolites from kidney, feces, liver, and serum samples. ORG mice showed increased urinary albumin creatinine ratio, cholesterol, triglyceride levels, and glomerular diameter compared with NCD mice (all <i>P</i> < 0.05). EMPA treatment significantly alleviated these parameters (all <i>P</i> < 0.05). Multitissue metabolomics analysis revealed lipid metabolic reprogramming in ORG mice, which was significantly altered by EMPA treatment. MetOrigin analysis showed a close association between EMPA-related lipid metabolic pathways and gut microbiota alterations, characterized by reduced abundances of <i>Firmicutes</i> and <i>Desulfovibrio</i> and increased abundance of <i>Akkermansia</i> (all <i>P</i> < 0.05). The metabolic homeostasis of ORG mice, especially in lipid metabolism, was disrupted and closely associated with gut microbiota alterations, contributing to the progression of ORG. EMPA treatment improved kidney function and morphology by regulating lipid metabolism through the gut-kidney axis, highlighting a novel therapeutic approach for ORG. <b>NEW & NOTEWORTHY</b> Our study uncovered that empagliflozin (EMPA) potentially protects renal function and morphology in obesity-related glomerulopathy (ORG) mice by regulating the gut-kidney axis. EMPA's reno-protective effects in ORG mice are associated with the lipid metabolism, especially in glycerophospholipid metabolism and the pantothenate/CoA synthesis pathways. EMPA's modulation of gut microbiota appears to be pivotal in suppressing glycerol 3-phosphate and CoA synthesis. The insights into gut microbiota-host metabolic interactions offer a novel therapeutic approach for ORG.</p>","PeriodicalId":7585,"journal":{"name":"American journal of physiology. Cell physiology","volume":" ","pages":"C994-C1011"},"PeriodicalIF":5.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11481992/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142054662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Tumor microenvironment-like conditions alter pancreatic cancer cell metabolism and behavior.","authors":"Georgina Louise Gardner, Jeffrey Alan Stuart","doi":"10.1152/ajpcell.00452.2024","DOIUrl":"10.1152/ajpcell.00452.2024","url":null,"abstract":"<p><p>The tumor microenvironment is complex and dynamic, characterized by poor vascularization, limited nutrient availability, hypoxia, and an acidic pH. This environment plays a critical role in driving cancer progression. However, standard cell culture conditions used to study cancer cell biology in vitro fail to replicate the in vivo environment of tumors. Recently, \"physiological\" cell culture media that closely resemble human plasma have been developed (e.g., Plasmax, HPLM), along with more frequent adoption of physiological oxygen conditions (1%-8% O<sub>2</sub>). Nonetheless, further refinement of tumor-specific culture conditions may be needed. In this study, we describe the development of a tumor microenvironment medium (TMEM) based on murine pancreatic ductal adenocarcinoma (PDAC) tumor interstitial fluid. Using RNA-sequencing, we show that murine PDAC cells (KPCY) cultured in tumor-like conditions (TMEM, pH 7.0, 1.5% O<sub>2</sub>) exhibit profound differences in gene expression compared with plasma-like conditions (mouse plasma medium, pH 7.4, 5% O<sub>2</sub>). Specifically, the expression of genes and pathways associated with cell migration, biosynthesis, angiogenesis, and epithelial-to-mesenchymal transition were altered, suggesting tumor-like conditions promote metastatic phenotypes and metabolic remodeling. Using functional assays to validate RNA-seq data, we confirmed increased motility at 1.5% O<sub>2</sub>/TMEM, despite reduced cell proliferation. Moreover, a hallmark shift to glycolytic metabolism was identified via measurement of glucose uptake/lactate production and mitochondrial respiration. Taken together, these findings demonstrate that growth in 1.5% O<sub>2</sub>/TMEM alters several biological responses in ways relevant to cancer biology, and more closely models hallmark cancerous phenotypes in culture. This highlights the importance of establishing tumor microenvironment-like conditions in standard cancer research. <b>NEW & NOTEWORTHY</b> Standard cell culture conditions do not replicate the complex tumor microenvironment experienced by cells in vivo. Although currently available plasma-like media are superior to traditional supraphysiological media, they fail to model tumor-like conditions. Using RNA-seq analysis and functional metabolic and migratory assays, we show that tumor microenvironment medium (TMEM), used with representative tumor hypoxia, better models cancerous phenotypes in culture. This emphasizes the critical importance of accurately modeling the tumor microenvironment in cancer research.</p>","PeriodicalId":7585,"journal":{"name":"American journal of physiology. Cell physiology","volume":" ","pages":"C959-C978"},"PeriodicalIF":5.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142054663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Junctions at the crossroads: the impact of mechanical cues on endothelial cell-cell junction conformations and vascular permeability.","authors":"Ken D Brandon, William E Frank, Kimberly M Stroka","doi":"10.1152/ajpcell.00605.2023","DOIUrl":"10.1152/ajpcell.00605.2023","url":null,"abstract":"<p><p>Cells depend on precisely regulating barrier function within the vasculature to maintain physiological stability and facilitate essential substance transport. Endothelial cells achieve this through specialized adherens and tight junction protein complexes, which govern paracellular permeability across vascular beds. Adherens junctions, anchored by vascular endothelial (VE)-cadherin and associated catenins to the actin cytoskeleton, mediate homophilic adhesion crucial for barrier integrity. In contrast, tight junctions composed of occludin, claudin, and junctional adhesion molecule A interact with Zonula Occludens proteins, reinforcing intercellular connections essential for barrier selectivity. Endothelial cell-cell junctions exhibit dynamic conformations during development, maturation, and remodeling, regulated by local biochemical and mechanical cues. These structural adaptations play pivotal roles in disease contexts such as chronic inflammation, where junctional remodeling contributes to increased vascular permeability observed in conditions from cancer to cardiovascular diseases. Conversely, the brain microvasculature's specialized junctional arrangements pose challenges for therapeutic drug delivery due to their unique molecular compositions and tight organization. This commentary explores the molecular mechanisms underlying endothelial cell-cell junction conformations and their implications for vascular permeability. By highlighting recent advances in quantifying junctional changes and understanding mechanotransduction pathways, we elucidate how physical forces from cellular contacts and hemodynamic flow influence junctional dynamics.</p>","PeriodicalId":7585,"journal":{"name":"American journal of physiology. Cell physiology","volume":" ","pages":"C1073-C1086"},"PeriodicalIF":5.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11481987/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141915846","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Physiologic hypoxia in the intestinal mucosa: a central role for short-chain fatty acids.","authors":"Timothy Wang, Ruth X Wang, Sean P Colgan","doi":"10.1152/ajpcell.00472.2024","DOIUrl":"10.1152/ajpcell.00472.2024","url":null,"abstract":"<p><p>The intestinal mucosa is a dynamic surface that facilitates interactions between the host and an outside world that includes trillions of microbes, collectively termed the microbiota. This fine balance is regulated by an energetically demanding physical and biochemical barrier that is formed by the intestinal epithelial cells. In addition, this homeostasis exists at an interface between the anaerobic colonic lumen and a highly oxygenated, vascularized lamina propria. The resultant oxygen gradient within the intestine establishes \"physiologic hypoxia\" as a central metabolic feature of the mucosa. Although oxygen is vital for energy production to meet cellular metabolism needs, the availability of oxygen has far-reaching influences beyond just energy provision. Recent studies have shown that the intestinal mucosa has purposefully adapted to use differential oxygen levels largely through the presence of short-chain fatty acids (SCFAs), particularly butyrate (BA). Intestinal epithelial cells use butyrate for a multitude of functions that promote mucosal homeostasis. In this review, we explore how the physiologic hypoxia profile interfaces with SCFAs to benefit host mucosal tissues.</p>","PeriodicalId":7585,"journal":{"name":"American journal of physiology. Cell physiology","volume":" ","pages":"C1087-C1093"},"PeriodicalIF":5.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11482044/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142003395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}