Pflugers Archiv : European journal of physiology最新文献

{"title":"Automated patch-clamp recordings for detecting activators and inhibitors of the epithelial sodium channel (ENaC).","authors":"Florian Sure, Markus Rapedius, Alexei Diakov, Marko Bertog, Alison Obergrussberger, Niels Fertig, Christoph Korbmacher, Alexandr V Ilyaskin","doi":"10.1007/s00424-025-03087-3","DOIUrl":"10.1007/s00424-025-03087-3","url":null,"abstract":"<p><p>The epithelial sodium channel (ENaC) is crucial for sodium absorption in several epithelial tissues including lung and kidney. Its involvement in various renal and pulmonary disorders makes ENaC a potential drug target. High-throughput screening using the automated patch-clamp (APC) technique appears to be a promising approach to discover novel ENaC modulators with (patho-)physiological and therapeutic implications. The aim of this methodological study was to establish APC measurements of ENaC-mediated currents. First, we confirmed functional expression of ENaC in a HEK293 cell line stably transfected with human αβγ-ENaC using conventional manual whole-cell patch-clamp recordings. For APC measurements, a standard enzymatic cell-detachment procedure was used to prepare single cell suspensions. This resulted in a high success rate of APC recordings with amiloride inhibitable ENaC currents. Using a γ-inhibitory peptide and the small molecule ENaC activator S3969, we demonstrate that APC recordings could reveal inhibitory as well as stimulatory effects on ENaC. Interestingly, the enzymatic cell-detachment protocol resulted in partial proteolytic ENaC activation. The portion of proteolytically activated channels could be reduced by prolonged incubation of suspended cells in cell culture medium. This recovery protocol enhanced the relative stimulatory effect of chymotrypsin, a prototypical serine protease known to cause proteolytic ENaC activation. Thus, this protocol may be particularly useful for identifying novel ENaC activators mimicking proteolytic channel activation. In conclusion, we have established a high-throughput screening method for the identification of novel ENaC activators and inhibitors using APC.</p>","PeriodicalId":19954,"journal":{"name":"Pflugers Archiv : European journal of physiology","volume":" ","pages":"857-872"},"PeriodicalIF":2.9,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12092551/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144032747","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sphingosine kinase 1 inhibition aggravates vascular smooth muscle cell calcification.","authors":"Mehdi Razazian, Sheyda Bahiraii, Isratul Jannat, Adéla Tiffner, Georg Beilhack, Bodo Levkau, Jakob Voelkl, Ioana Alesutan","doi":"10.1007/s00424-025-03068-6","DOIUrl":"10.1007/s00424-025-03068-6","url":null,"abstract":"<p><p>Medial vascular calcification is common in chronic kidney disease patients and linked to hyperphosphatemia. Upon phosphate exposure, intricate signaling events orchestrate pro-calcific effects in the vasculature mediated by vascular smooth muscle cells (VSMCs). Sphingosine kinase 1 (SPHK1) produces sphingosine-1-phosphate (S1P) and is associated with complex effects in the vascular system. The present study investigated a possible involvement of SPHK1 in VSMC calcification. Experiments were performed in primary human aortic VSMCs under pro-calcific conditions, with pharmacological inhibition or knockdown of SPHK1 or SPNS2 (a lysolipid transporter involved in cellular S1P export), as well as in Sphk1-deficient and wild-type mice treated with cholecalciferol. In VSMCs, SPHK1 expression was up-regulated by pro-calcific conditions. Calcification medium up-regulated osteogenic marker mRNA expression and activity as well as calcification of VSMCs, effects significantly augmented by co-treatment with the SPHK1 inhibitor SK1-IN-1. SK1-IN-1 alone was sufficient to up-regulate osteogenic signaling in VSMCs during control conditions. Similarly, the SPHK1 inhibitor PF-543 and SPHK1 knockdown up-regulated osteogenic signaling in VSMCs and aggravated VSMC calcification. In contrast, co-treatment with the SPNS2 inhibitor SLF1081851 suppressed osteogenic signaling and calcification of VSMCs, effects abolished by silencing of SPHK1. In addition, Sphk1 deficiency aggravated vascular calcification and aortic osteogenic marker expression in mice after cholecalciferol overload. In conclusion, SPHK1 inhibition, knockdown, or deficiency aggravates vascular pro-calcific signaling and calcification. The reduced calcification after inhibition of S1P export suggests a possible involvement of intracellular S1P, but further studies are required to elucidate the complex roles of SPHKs and S1P signaling in calcifying VSMCs.</p>","PeriodicalId":19954,"journal":{"name":"Pflugers Archiv : European journal of physiology","volume":" ","pages":"815-826"},"PeriodicalIF":2.9,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12092484/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143080789","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Consecutive SSCs increase the SSC effect in skinned rat muscle fibres.","authors":"Tobias Elst, Sven Weidner, André Tomalka, Daniel Hahn, Florian Kurt Paternoster, Wolfgang Seiberl, Tobias Siebert","doi":"10.1007/s00424-025-03088-2","DOIUrl":"10.1007/s00424-025-03088-2","url":null,"abstract":"<p><p>Muscle function is essential for generating force and movement, with stretch-shortening cycles (SSCs) playing a fundamental role in the economy of everyday locomotion. Compared with pure shortening contractions, the SSC effect is characterised by increased force, work, and power output during the SSC shortening phase. Few studies have investigated whether SSC effects transfer across consecutive SSCs. Therefore, we investigated SSC effects over three consecutive SSCs in skinned rat muscle fibres by analysing the isometric force immediately before stretch onset (F_onset), the peak force at the end of stretching (F_peak), and the minimum force at the end of shortening (F_min), along with mechanical (Work_SSC) and shortening work (Work_SHO) at different activation levels (20%, 60%, and 100%). Each SSC was followed by an isometric hold phase, allowing force to return to a steady state. Results indicated an increase in both F_peak (20.3%) and Work_SSC (60.9%) from SSC1 to SSC3 across all activation levels tested. At 20% and 60% activation, F_onset, F_min, and Work_SHO increased (range: 4.5-28.5%) from SSC1 to SSC3. However, at 100% activation, F_onset and Work_SHO remained unchanged, while F_min decreased (- 8.5%) from SSC1 to SSC3. These results suggest that the increase in SSC effects at submaximal activation may be primarily due to increased cross-bridge forces. The absence of increases in F_onset, F_min, and Work_SHO at 100% activation suggests that increases in F_peak and Work_SSC may not be attributed to increased cross-bridge force but could instead be caused by additional effects, possibly involving modulation of non-cross-bridge structures, likely titin, and their stiffness.</p>","PeriodicalId":19954,"journal":{"name":"Pflugers Archiv : European journal of physiology","volume":" ","pages":"873-888"},"PeriodicalIF":2.9,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12092553/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144037767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The formation and function of calciprotein particles.","authors":"Edward R Smith, Stephen G Holt","doi":"10.1007/s00424-025-03083-7","DOIUrl":"10.1007/s00424-025-03083-7","url":null,"abstract":"<p><p>Vertebrate extracellular fluids lie below the threshold for spontaneous calcium phosphate (Ca-P_i) precipitation; yet, they remain supersaturated enough to foster crystal growth if unchecked. Calciprotein particles (CPP) and their smaller precursor calciprotein monomers (CPM) have emerged as fast-acting \"mineral buffers\" that mitigate abrupt local oversaturation. Although these complexes typically contain only trace amounts of Ca-P_i relative to total plasma levels, they exhibit remarkably high turnover kinetics, with clearance from the circulation within minutes, far outpacing hormonal loops that operate on timescales of hours to days. By forming ephemeral colloidal assemblies, CPM/CPP help maintain fluid-phase stability and avert uncontrolled crystallization \"accidents\" in microenvironments such as the intestine or bone-remodeling sites. However, under chronic mineral stress, such as in chronic kidney disease, multiple inhibitory factors (e.g., fetuin-A, pyrophosphate) can become deficient, enabling persistent generation of more advanced, crystalline CPP species. These \"modified\" CPP can adsorb additional ligands (e.g., apolipoproteins, microbial remnants, growth factors) and have been linked to inflammatory and pro-calcific changes in vascular and immune cells. Despite their minor quantitative contribution, these rapidly mobilized colloids may exert outsized influence on vascular and skeletal homeostasis, underscoring the need to clarify their origins, biological roles, and potential therapeutic targeting in disorders of mineral metabolism.</p>","PeriodicalId":19954,"journal":{"name":"Pflugers Archiv : European journal of physiology","volume":" ","pages":"753-772"},"PeriodicalIF":2.9,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12092497/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144017128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"IRBITs, signaling molecules of great functional diversity.","authors":"Ying Liu, Xuhui Feng, Han Wu, Tianxiang Gui, Mingfeng Fu, Xudong Luo, Lei Zhao, Li-Ming Chen","doi":"10.1007/s00424-025-03095-3","DOIUrl":"https://doi.org/10.1007/s00424-025-03095-3","url":null,"abstract":"<p><p>IRBIT1 and IRBIT2 (collectively, the IRBITs) are signaling molecules with great universality in their expression (ubiquitous distribution in all major tissues in animals) and considerable versatility in their biological functions. Structurally, the IRBITs are highly homologous to S-adenosyl-L-homocysteine hydrolase (AHCY). However, the IRBITs had lost the catalytic activity during the evolution but gained new functions by the addition of a unique N-terminal IRBIT domain. By direct protein interaction, the IRBITs modulate the functions of an array of target proteins of distinct biological functions, ranging from membrane channels and transporters to cytosolic protein kinase, lipid kinases, ribonucleotide reductase, etc. The interaction of the IRBITs with specific target proteins is modulated by the redox couple NAD⁺/NADH. The IRBITs are involved in the regulation of many cellular processes, such as Ca²⁺ signaling, intracellular pH regulation, transepithelial transport of electrolytes and fluid, apoptosis, and DNA metabolism. However, what we have known about the IRBITs is likely just the tip of the iceberg. The present review covers the expression and distribution, physiological and pathological roles, and the structural organization of the IRBITs. It provides a comprehensive review on the binding partners of the IRBITs. Finally, the review addresses the evolution of the IRBITs in reference to the evolution of AHCY.</p>","PeriodicalId":19954,"journal":{"name":"Pflugers Archiv : European journal of physiology","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144187599","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microbiota, mitochondria, and epigenetics in health and disease: converging pathways to solve the puzzle.","authors":"Natalia Lucia Rukavina Mikusic, Paula Denise Prince, Marcelo Roberto Choi, Luiz Gustavo A Chuffa, Vinícius Augusto Simão, Claudia Castro, Walter Manucha, Isabel Quesada","doi":"10.1007/s00424-025-03072-w","DOIUrl":"10.1007/s00424-025-03072-w","url":null,"abstract":"<p><p>Dysbiosis, which refers to an imbalance in the composition of the gut microbiome, has been associated with a range of metabolic disorders, including type 2 diabetes, obesity, and metabolic syndrome. Although the exact mechanisms connecting gut dysbiosis to these conditions are not fully understood, various lines of evidence strongly suggest a substantial role for the interaction between the gut microbiome, mitochondria, and epigenetics. Current studies suggest that the gut microbiome has the potential to affect mitochondrial function and biogenesis through the production of metabolites. A well-balanced microbiota plays a pivotal role in supporting normal mitochondrial and cellular functions by providing metabolites that are essential for mitochondrial bioenergetics and signaling pathways. Conversely, in the context of illnesses, an unbalanced microbiota can impact mitochondrial function, leading to increased aerobic glycolysis, reduced oxidative phosphorylation and fatty acid oxidation, alterations in mitochondrial membrane permeability, and heightened resistance to cellular apoptosis. Mitochondrial activity can also influence the composition and function of the gut microbiota. Because of the intricate interplay between nuclear and mitochondrial communication, the nuclear epigenome can regulate mitochondrial function, and conversely, mitochondria can produce metabolic signals that initiate epigenetic changes within the nucleus. Given the epigenetic modifications triggered by metabolic signals from mitochondria in response to stress or damage, targeting an imbalanced microbiota through interventions could offer a promising strategy to alleviate the epigenetic alterations arising from disrupted mitochondrial signaling.</p>","PeriodicalId":19954,"journal":{"name":"Pflugers Archiv : European journal of physiology","volume":" ","pages":"635-655"},"PeriodicalIF":2.9,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143670557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The NFAT5 chronicles: a transcription factor's tale of hypoxia, pulmonary drama, and endothelial resilience to hypoxia.","authors":"Dörthe M Katschinski","doi":"10.1007/s00424-025-03080-w","DOIUrl":"10.1007/s00424-025-03080-w","url":null,"abstract":"","PeriodicalId":19954,"journal":{"name":"Pflugers Archiv : European journal of physiology","volume":" ","pages":"683-684"},"PeriodicalIF":2.9,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12003427/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143736122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatio-temporal segregation between sensory relay and swallowing pre-motor population activities by optical imaging in the rat nucleus of the solitary tract.","authors":"Shinya Fuse, Yoichiro Sugiyama, Rishi R Dhingra, Shigeru Hirano, Mathias Dutschmann, Yasumasa Okada, Yoshitaka Oku","doi":"10.1007/s00424-025-03065-9","DOIUrl":"10.1007/s00424-025-03065-9","url":null,"abstract":"<p><p>The nucleus tractus solitarius (NTS) contains neurons that relay sensory swallowing commands information from the oropharyngeal cavity and swallowing premotor neurons of the dorsal swallowing group (DSG). However, the spatio-temporal dynamics of the interplay between the sensory relay and the DSG is not well understood. Here, we employed fluorescence imaging after microinjection of the calcium indicator into the NTS in an arterially perfused brainstem preparation of rat (n = 8) to investigate neuronal population activity in the NTS in response to superior laryngeal nerve (SLN) stimulation. Respiratory and swallowing motor activities were determined by simultaneous recordings of phrenic and vagal nerve activity (PNA, VNA). The analysis of SLN stimulation near the threshold triggering a swallowing allowed us to analyze Ca²⁺ signals related to the sensory relay and the DSG. We show that activation of sensory relay neurons triggers spatially confined Ca²⁺ signals exclusively unilateral to the stimulated SLN at short latencies (114.3 ± 94.4 ms). However, SLN-evoked swallowing triggered Ca²⁺ signals bilaterally at longer latencies (200 ± 145.2 ms) and engaged anatomically distributed DSG activity across the dorsal medulla oblongata. The Ca²⁺ signals originating from the DSG preceded evoked VNA swallow motor bursts, thus the swallowing premotor neurons that drive laryngeal motor pools are located outside the DSG. In conclusion, the study illuminates the spatial-temporal features of sensory-motor integration of swallowing in the NTS and further supports the hypothesis that the NTS harbors swallowing pre-motor neurons that may generate the swallowing motor activity, while first-order pre-motor pools are located outside the DSG.</p>","PeriodicalId":19954,"journal":{"name":"Pflugers Archiv : European journal of physiology","volume":" ","pages":"719-727"},"PeriodicalIF":2.9,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12003619/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143040911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Epidemiology of metabolic syndrome.","authors":"Iris Pigeot, Wolfgang Ahrens","doi":"10.1007/s00424-024-03051-7","DOIUrl":"10.1007/s00424-024-03051-7","url":null,"abstract":"<p><p>The global increase of overweight and obesity in children and adults is one of the most prominent public health threats, often accompanied by insulin resistance, hypertension, and dyslipidemia. The simultaneous occurrence of these health problems is referred to as metabolic syndrome. Various criteria have been proposed to define this syndrome, but no general consensus on the specific markers and the respective cut-offs has been achieved yet. As a consequence, it is difficult to assess regional variations and temporal trends and to obtain a comprehensive picture of the global burden of this major health threat. This limitation is most striking in childhood and adolescence, when metabolic parameters change with developmental stage. Obesity and related metabolic disorders develop early in life and then track into adulthood, i.e., the metabolic syndrome seems to originate in the early life course. Thus, it would be important to monitor the trajectories of cardio-metabolic parameters from early on. We will summarize selected key studies to provide a narrative overview of the global epidemiology of the metabolic syndrome while considering the limitations that hinder us to provide a comprehensive full picture of the problem. A particular focus will be given to the situation in children and adolescents and the risk factors impacting on their cardio-metabolic health. This summary will be complemented by key findings of a pan-European children cohort and first results of a large German adult cohort.</p>","PeriodicalId":19954,"journal":{"name":"Pflugers Archiv : European journal of physiology","volume":" ","pages":"669-680"},"PeriodicalIF":2.9,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12003477/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143040888","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The enigma of ENaC activation by proteolytic cleavage: a never ending quest?","authors":"Eric Feraille, Ali Sassi, Monika Gjorgjieva","doi":"10.1007/s00424-025-03081-9","DOIUrl":"10.1007/s00424-025-03081-9","url":null,"abstract":"","PeriodicalId":19954,"journal":{"name":"Pflugers Archiv : European journal of physiology","volume":" ","pages":"681-682"},"PeriodicalIF":2.9,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143753408","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}