Pub Date : 2023-07-01DOI: 10.1152/physiol.00014.2023
Christopher England
This issue of Physiology features four excellent review articles that highlight current research and discuss untapped areas for future work across a range of topics in physiology. First, we explore the impact that the loss of the Y chromosome in white blood cells has on men's health. Next, we discuss the pathophysiological roles of the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) in chronic inflammation. Third, we discuss how certain animals remain hydrated in seawater. Finally, we present on the systemic reprogramming of endothelial cell signaling in metastasis and cachexia.
{"title":"Physiology in Perspective.","authors":"Christopher England","doi":"10.1152/physiol.00014.2023","DOIUrl":"https://doi.org/10.1152/physiol.00014.2023","url":null,"abstract":"<p><p>This issue of <i>Physiology</i> features four excellent review articles that highlight current research and discuss untapped areas for future work across a range of topics in physiology. First, we explore the impact that the loss of the Y chromosome in white blood cells has on men's health. Next, we discuss the pathophysiological roles of the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) in chronic inflammation. Third, we discuss how certain animals remain hydrated in seawater. Finally, we present on the systemic reprogramming of endothelial cell signaling in metastasis and cachexia.</p>","PeriodicalId":49694,"journal":{"name":"Physiology","volume":"38 4","pages":"160"},"PeriodicalIF":8.4,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9691348","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-01DOI: 10.1152/physiol.00005.2023
Martin Grosell, Amanda M Oehlert
Reduction of intestinal lumen osmotic pressure by the formation of Ca(Mg)CO3, "ichthyocarbonate," is essential for osmoregulation by the only vertebrate group, ray-finned fishes, widely capable of hydrating by ingesting seawater. Ichthyocarbonate formation and excretion are under elaborate physiological control and play an important, yet still poorly defined, role in the oceanic carbon cycle.
{"title":"Staying Hydrated in Seawater.","authors":"Martin Grosell, Amanda M Oehlert","doi":"10.1152/physiol.00005.2023","DOIUrl":"https://doi.org/10.1152/physiol.00005.2023","url":null,"abstract":"<p><p>Reduction of intestinal lumen osmotic pressure by the formation of Ca(Mg)CO<sub>3</sub>, \"ichthyocarbonate,\" is essential for osmoregulation by the only vertebrate group, ray-finned fishes, widely capable of hydrating by ingesting seawater. Ichthyocarbonate formation and excretion are under elaborate physiological control and play an important, yet still poorly defined, role in the oceanic carbon cycle.</p>","PeriodicalId":49694,"journal":{"name":"Physiology","volume":"38 4","pages":"0"},"PeriodicalIF":8.4,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9956032","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-01DOI: 10.1152/physiol.00031.2022
Hiroshi Maekawa, Margaret Elizabeth Fain, Koichiro Wasano
The cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) inflammatory pathway is a component of the innate immune system that recognizes cytosolic nucleic acids. The pathway has been implicated in several processes including aging, autoinflammatory conditions, cancer, and metabolic diseases. The cGAS-STING pathway represents a promising therapeutic target in a variety of chronic inflammatory diseases.
{"title":"Pathophysiological Roles of the cGAS-STING Inflammatory Pathway.","authors":"Hiroshi Maekawa, Margaret Elizabeth Fain, Koichiro Wasano","doi":"10.1152/physiol.00031.2022","DOIUrl":"https://doi.org/10.1152/physiol.00031.2022","url":null,"abstract":"<p><p>The cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) inflammatory pathway is a component of the innate immune system that recognizes cytosolic nucleic acids. The pathway has been implicated in several processes including aging, autoinflammatory conditions, cancer, and metabolic diseases. The cGAS-STING pathway represents a promising therapeutic target in a variety of chronic inflammatory diseases.</p>","PeriodicalId":49694,"journal":{"name":"Physiology","volume":"38 4","pages":"0"},"PeriodicalIF":8.4,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9604216","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-01DOI: 10.1152/physiol.0009.2021_COR
{"title":"Corrigendum for Lee CE, volume 36, 2021, p. 335–349","authors":"","doi":"10.1152/physiol.0009.2021_COR","DOIUrl":"https://doi.org/10.1152/physiol.0009.2021_COR","url":null,"abstract":"","PeriodicalId":49694,"journal":{"name":"Physiology","volume":"38 4","pages":"0"},"PeriodicalIF":8.4,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9569504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-01Epub Date: 2023-03-28DOI: 10.1152/physiol.00008.2023
Soichi Sano, Mark C Thel, Kenneth Walsh
We present a brief introduction of loss of Y chromosome (LOY) in blood and describe the known risk factors for this condition. We then overview the associations between LOY and age-related disease traits. Finally, we discuss murine models and the potential mechanisms by which LOY contributes to disease.
我们简要介绍了血液中的 Y 染色体缺失(LOY),并描述了这种情况的已知风险因素。然后,我们概述了 LOY 与年龄相关疾病特征之间的关联。最后,我们讨论了小鼠模型和 LOY 导致疾病的潜在机制。
{"title":"Mosaic Loss of Y Chromosome in White Blood Cells: Its Impact on Men's Health.","authors":"Soichi Sano, Mark C Thel, Kenneth Walsh","doi":"10.1152/physiol.00008.2023","DOIUrl":"10.1152/physiol.00008.2023","url":null,"abstract":"<p><p>We present a brief introduction of loss of Y chromosome (LOY) in blood and describe the known risk factors for this condition. We then overview the associations between LOY and age-related disease traits. Finally, we discuss murine models and the potential mechanisms by which LOY contributes to disease.</p>","PeriodicalId":49694,"journal":{"name":"Physiology","volume":"38 4","pages":"0"},"PeriodicalIF":5.3,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10281780/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9705887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-01DOI: 10.1152/physiol.00001.2023
Stephanie F Preuss, Denise Grieshober, Hellmut G Augustin
Proliferating cancer cells secrete a multitude of factors impacting metabolism, interorgan communication, and tumor progression. The distribution of tumor-derived factors to distant organs occurs via the circulation, which provides an extensive reactive surface lined by endothelial cells. Primary tumor-derived proteins impact cancer progression by modulating endothelial cell activation at the (pre-)metastatic niche, which affects tumor cell dissemination as well as the outgrowth of seeded metastatic cells into overt tumors. In addition, new insight indicates that endothelial cell signaling contributes to metabolic symptoms of cancer, including cancer-associated cachexia, opening a new field of vascular metabolism research. This review addresses how tumor-derived factors systemically affect endothelial cell signaling and activation and impact distant organs as well as tumor progression.
{"title":"Systemic Reprogramming of Endothelial Cell Signaling in Metastasis and Cachexia.","authors":"Stephanie F Preuss, Denise Grieshober, Hellmut G Augustin","doi":"10.1152/physiol.00001.2023","DOIUrl":"https://doi.org/10.1152/physiol.00001.2023","url":null,"abstract":"<p><p>Proliferating cancer cells secrete a multitude of factors impacting metabolism, interorgan communication, and tumor progression. The distribution of tumor-derived factors to distant organs occurs via the circulation, which provides an extensive reactive surface lined by endothelial cells. Primary tumor-derived proteins impact cancer progression by modulating endothelial cell activation at the (pre-)metastatic niche, which affects tumor cell dissemination as well as the outgrowth of seeded metastatic cells into overt tumors. In addition, new insight indicates that endothelial cell signaling contributes to metabolic symptoms of cancer, including cancer-associated cachexia, opening a new field of vascular metabolism research. This review addresses how tumor-derived factors systemically affect endothelial cell signaling and activation and impact distant organs as well as tumor progression.</p>","PeriodicalId":49694,"journal":{"name":"Physiology","volume":"38 4","pages":"0"},"PeriodicalIF":8.4,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10281790/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9710402","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-05-01DOI: 10.1152/physiol.2023.38.s1.5733420
Jamal M. Alzahrani, Bryce J Gambino, C. Delgado, Michael T. Rua, Iris Young, Kevin J. Cusack, T. Clanton
Exertional heat stroke (EHS) is a life-threatening illness that can lead to short- and long-term adverse health outcomes. Several human epidemiology studies have shown that heat stroke exposure is highly associated with the development of cardiovascular disease later in life. However, whether EHS causes heart disease or individuals with predispositions to heart disease are more susceptible to EHS is unknown. Previously, our laboratory demonstrated metabolic abnormalities in the myocardium of mice, two weeks after EHS, characterized by lipid accumulation. In this study, we hypothesized that EHS exposure in mice leads to long-term susceptibilities to cardiovascular disease that is accelerated by co-exposure to a Western diet. METHODS: Sixty-four male (n=32) and female (n=32) C57BL/6 mice were exposed to either EHS (forced wheel running in 34.5°C for males and 37.5°C for females) or sham exercise controls (EXC, forced wheel running in ~22.5°C). Fourteen days later, mice were placed on either a Western diet (WD) or a standard diet (SD) and then followed for 9 additional weeks. At week 12, post interventions (EHS or EXC), animals were euthanized and samples collected for analysis. RESULTS: Male mice exposed to EHS with either WD ( P = 0.0001) or SD ( P = 0.0001) gained more body mass over the 9-week diet period compared to diet matched EXC controls. Also, regardless of diet, male mice exposed to EHS consumed more food compared to matched EXC (WD: P < 0.005 and SD: P < 0.04). However, only female mice exposed to EHS with WD gained more body mass compared to female EXC mice with WD ( P < 0.04). At the end of the study, and regardless of diet, male mice exposed to EHS showed enlarged hearts in terms of absolute mass (WD: P=0.0241, SD: P=0.0069) and relative mass/tibia length (WD: P=0.013, SD P=0.03). On the other hand, EHS female mice exposed to WD showed enlarged heart mass compared to EHS on SD ( P=0.0005). CONCLUSIONS: These results demonstrate that EHS exposure in mice leads to a long-term metabolic disorder characterized by greatly accelerated weight gain, greater appetite and cardiac hypertrophy. Effects were more evident and consistent in males. Such a response is typical of early stages of metabolic syndrome and would likely contribute to eventual cardiac disease. Therefore, the data is consistent with EHS exposure being a risk factor for long term heart disease. U.S. Army Grant BA180078 and from King Saud University, Saudi Arabia This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.
{"title":"Exertional heart stroke causes long-term obesity and cardiac hypertrophy in mice","authors":"Jamal M. Alzahrani, Bryce J Gambino, C. Delgado, Michael T. Rua, Iris Young, Kevin J. Cusack, T. Clanton","doi":"10.1152/physiol.2023.38.s1.5733420","DOIUrl":"https://doi.org/10.1152/physiol.2023.38.s1.5733420","url":null,"abstract":"Exertional heat stroke (EHS) is a life-threatening illness that can lead to short- and long-term adverse health outcomes. Several human epidemiology studies have shown that heat stroke exposure is highly associated with the development of cardiovascular disease later in life. However, whether EHS causes heart disease or individuals with predispositions to heart disease are more susceptible to EHS is unknown. Previously, our laboratory demonstrated metabolic abnormalities in the myocardium of mice, two weeks after EHS, characterized by lipid accumulation. In this study, we hypothesized that EHS exposure in mice leads to long-term susceptibilities to cardiovascular disease that is accelerated by co-exposure to a Western diet. METHODS: Sixty-four male (n=32) and female (n=32) C57BL/6 mice were exposed to either EHS (forced wheel running in 34.5°C for males and 37.5°C for females) or sham exercise controls (EXC, forced wheel running in ~22.5°C). Fourteen days later, mice were placed on either a Western diet (WD) or a standard diet (SD) and then followed for 9 additional weeks. At week 12, post interventions (EHS or EXC), animals were euthanized and samples collected for analysis. RESULTS: Male mice exposed to EHS with either WD ( P = 0.0001) or SD ( P = 0.0001) gained more body mass over the 9-week diet period compared to diet matched EXC controls. Also, regardless of diet, male mice exposed to EHS consumed more food compared to matched EXC (WD: P < 0.005 and SD: P < 0.04). However, only female mice exposed to EHS with WD gained more body mass compared to female EXC mice with WD ( P < 0.04). At the end of the study, and regardless of diet, male mice exposed to EHS showed enlarged hearts in terms of absolute mass (WD: P=0.0241, SD: P=0.0069) and relative mass/tibia length (WD: P=0.013, SD P=0.03). On the other hand, EHS female mice exposed to WD showed enlarged heart mass compared to EHS on SD ( P=0.0005). CONCLUSIONS: These results demonstrate that EHS exposure in mice leads to a long-term metabolic disorder characterized by greatly accelerated weight gain, greater appetite and cardiac hypertrophy. Effects were more evident and consistent in males. Such a response is typical of early stages of metabolic syndrome and would likely contribute to eventual cardiac disease. Therefore, the data is consistent with EHS exposure being a risk factor for long term heart disease. U.S. Army Grant BA180078 and from King Saud University, Saudi Arabia This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.","PeriodicalId":49694,"journal":{"name":"Physiology","volume":"16 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90243300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-05-01DOI: 10.1152/physiol.2023.38.s1.5732992
Madison Boskind, Nikitha Nelapudi, Grace Williamson, Rucha Juarez, Bobby Mendez, Lubo Zhang, A. Blood, Christopher Wilson, S. Wilson
Intracellular Ca2+ signals are well regarded for their regulation of cellular processes ranging from myocyte contraction, hormonal secretion, neural transmission, cellular metabolism, transcriptional regulation, and cell proliferation. Measurement of cellular Ca2+ is routinely performed using fluorescent microscopy techniques with biological indicators. Analysis of deterministic signals is relatively straightforward as relevant data can be discriminated based on the timing of cellular responses. However, analysis of stochastic events in complex tissues takes considerable time and effort that often includes visual analysis by trained investigators. The purpose of the current study was to determine if the image analysis workflow could be automated without introducing errors. This evaluation was addressed by re-analyzing a published “gold standard” dataset through visual analysis of Ca2+ signals from recordings made in pulmonary arterial myocytes of en face arterial preparations. We applied a combination of data-driven and statistical approaches with comparisons to our published data to assess the fidelity of the various approaches. Regions of interest with Ca2+ oscillations were detected automatically post-hoc using the LC Pro plug-in for ImageJ. Oscillatory signals were separated based on event durations between 4 and 40 seconds. These data were filtered based on cutoffs obtained from multiple methods and compared to the published manually curated “gold standard” dataset. After filtering, the number of true positives, false positives, and false negatives were calculated through comparisons to the gold standard dataset. Positive predictive value, sensitivity and false discovery rates were calculated. There were very few significant differences between the quality of the events and no systematic biases based on the data curation or filtering techniques. The lack of difference between manual data curation and statistically derived critical cutoff techniques leads us to question the importance of manually curating stochastic Ca2+ event datasets using labor-intensive visual observation techniques. NIH R01HL155295, R01HL149608 This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.
{"title":"Improved workflow for analysis of smooth muscle calcium signals from intact arterial preparations","authors":"Madison Boskind, Nikitha Nelapudi, Grace Williamson, Rucha Juarez, Bobby Mendez, Lubo Zhang, A. Blood, Christopher Wilson, S. Wilson","doi":"10.1152/physiol.2023.38.s1.5732992","DOIUrl":"https://doi.org/10.1152/physiol.2023.38.s1.5732992","url":null,"abstract":"Intracellular Ca2+ signals are well regarded for their regulation of cellular processes ranging from myocyte contraction, hormonal secretion, neural transmission, cellular metabolism, transcriptional regulation, and cell proliferation. Measurement of cellular Ca2+ is routinely performed using fluorescent microscopy techniques with biological indicators. Analysis of deterministic signals is relatively straightforward as relevant data can be discriminated based on the timing of cellular responses. However, analysis of stochastic events in complex tissues takes considerable time and effort that often includes visual analysis by trained investigators. The purpose of the current study was to determine if the image analysis workflow could be automated without introducing errors. This evaluation was addressed by re-analyzing a published “gold standard” dataset through visual analysis of Ca2+ signals from recordings made in pulmonary arterial myocytes of en face arterial preparations. We applied a combination of data-driven and statistical approaches with comparisons to our published data to assess the fidelity of the various approaches. Regions of interest with Ca2+ oscillations were detected automatically post-hoc using the LC Pro plug-in for ImageJ. Oscillatory signals were separated based on event durations between 4 and 40 seconds. These data were filtered based on cutoffs obtained from multiple methods and compared to the published manually curated “gold standard” dataset. After filtering, the number of true positives, false positives, and false negatives were calculated through comparisons to the gold standard dataset. Positive predictive value, sensitivity and false discovery rates were calculated. There were very few significant differences between the quality of the events and no systematic biases based on the data curation or filtering techniques. The lack of difference between manual data curation and statistically derived critical cutoff techniques leads us to question the importance of manually curating stochastic Ca2+ event datasets using labor-intensive visual observation techniques. NIH R01HL155295, R01HL149608 This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.","PeriodicalId":49694,"journal":{"name":"Physiology","volume":"4 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90284859","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-05-01DOI: 10.1152/physiol.2023.38.s1.5728289
J. Meegan, L. Ware, J. Bastarache
Introduction: Disruption of the microvascular endothelial barrier is a critical pathological feature of sepsis-induced acute lung injury. Plasma cell-free hemoglobin (CFH) is elevated in approximately 80% of patients with sepsis and is independently associated with development of acute respiratory distress syndrome (ARDS) and mortality. Oxidized CFH (ferric, 3+) can oxidize low-density lipoprotein (oxLDL), which signals through its major endothelial receptor, the lectin-like oxidized LDL receptor 1 (LOX-1), to cause endothelial dysfunction through several pro-inflammatory pathways including activation of mitogen-activated protein kinases (MAPKs). However, little is known regarding whether LOX-1 receptor signaling leads to microvascular endothelial hyperpermeability or acute lung injury, especially in the context of sepsis. We hypothesized that oxidation of LDL by CFH contributes to lung microvascular endothelial barrier dysfunction and worse outcomes during sepsis through LOX-1 and downstream p38 MAPK. Methods: To test whether generation of oxLDL by CFH is associated with endothelial injury in clinical sepsis, circulating levels of CFH, oxLDL, and vascular injury marker sVE-cadherin were measured in 24 sepsis patients via ELISA and tested for association with development of ARDS. LDL was oxidized by combining LDL with CFH in a test tube overnight at 37°C and oxLDL was quantified by TBARS assay. In primary human lung microvascular endothelial cells (HLMVEC) transendothelial electrical resistance (TER), a measure of barrier dysfunction, was assessed by Electric Cell-substrate Impedance Sensing (ECIS). LOX-1 receptor was blocked using BI-0115 (Boehringer Ingelheim, 20 μM) and p38 MAPK was inhibited using NiPp (100 μM). Results: In sepsis patients, plasma oxLDL levels correlated with CFH (r=0.686, p=0.016) and sVE-cadherin (r=0.603, p=0.012), and tended to be higher in those who developed ARDS (38 U/L [IQR 27, 45] vs. 27 U/L [IQR 19, 35], p=0.1). Oxidation of LDL by CFH exacerbated HLMVEC barrier dysfunction compared to control, LDL, or CFH. Barrier dysfunction induced by CFH or oxLDL was attenuated by blocking the LOX-1 receptor or p38 MAPK. Conclusions: Increased plasma CFH and oxLDL are associated with vascular injury during clinical sepsis; one mechanism by which CFH may cause vascular hyperpermeability and sepsis-mediated lung injury is through oxidation of LDL which can drive signaling through the endothelial LOX-1 receptor and activation of p38 MAPK. NIH R35HL150783, R21GM144915, R01HL158906, R01HL164937, T32HL094296; Parker B. Francis Fellowship This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.
{"title":"Cell-free hemoglobin-mediated oxidation of low-density lipoprotein (oxLDL) contributes to lung microvascular endothelial dysfunction during sepsis","authors":"J. Meegan, L. Ware, J. Bastarache","doi":"10.1152/physiol.2023.38.s1.5728289","DOIUrl":"https://doi.org/10.1152/physiol.2023.38.s1.5728289","url":null,"abstract":"Introduction: Disruption of the microvascular endothelial barrier is a critical pathological feature of sepsis-induced acute lung injury. Plasma cell-free hemoglobin (CFH) is elevated in approximately 80% of patients with sepsis and is independently associated with development of acute respiratory distress syndrome (ARDS) and mortality. Oxidized CFH (ferric, 3+) can oxidize low-density lipoprotein (oxLDL), which signals through its major endothelial receptor, the lectin-like oxidized LDL receptor 1 (LOX-1), to cause endothelial dysfunction through several pro-inflammatory pathways including activation of mitogen-activated protein kinases (MAPKs). However, little is known regarding whether LOX-1 receptor signaling leads to microvascular endothelial hyperpermeability or acute lung injury, especially in the context of sepsis. We hypothesized that oxidation of LDL by CFH contributes to lung microvascular endothelial barrier dysfunction and worse outcomes during sepsis through LOX-1 and downstream p38 MAPK. Methods: To test whether generation of oxLDL by CFH is associated with endothelial injury in clinical sepsis, circulating levels of CFH, oxLDL, and vascular injury marker sVE-cadherin were measured in 24 sepsis patients via ELISA and tested for association with development of ARDS. LDL was oxidized by combining LDL with CFH in a test tube overnight at 37°C and oxLDL was quantified by TBARS assay. In primary human lung microvascular endothelial cells (HLMVEC) transendothelial electrical resistance (TER), a measure of barrier dysfunction, was assessed by Electric Cell-substrate Impedance Sensing (ECIS). LOX-1 receptor was blocked using BI-0115 (Boehringer Ingelheim, 20 μM) and p38 MAPK was inhibited using NiPp (100 μM). Results: In sepsis patients, plasma oxLDL levels correlated with CFH (r=0.686, p=0.016) and sVE-cadherin (r=0.603, p=0.012), and tended to be higher in those who developed ARDS (38 U/L [IQR 27, 45] vs. 27 U/L [IQR 19, 35], p=0.1). Oxidation of LDL by CFH exacerbated HLMVEC barrier dysfunction compared to control, LDL, or CFH. Barrier dysfunction induced by CFH or oxLDL was attenuated by blocking the LOX-1 receptor or p38 MAPK. Conclusions: Increased plasma CFH and oxLDL are associated with vascular injury during clinical sepsis; one mechanism by which CFH may cause vascular hyperpermeability and sepsis-mediated lung injury is through oxidation of LDL which can drive signaling through the endothelial LOX-1 receptor and activation of p38 MAPK. NIH R35HL150783, R21GM144915, R01HL158906, R01HL164937, T32HL094296; Parker B. Francis Fellowship This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.","PeriodicalId":49694,"journal":{"name":"Physiology","volume":"78 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90360074","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-05-01DOI: 10.1152/physiol.2023.38.s1.5793685
L. Petersen
Exercise induced arterial hypertension and post-exercise arterial hypotension (PEH) are well-described phenomena with direct impact on cerebral blood flow. Cerebral perfusion pressure is given by the difference between mean arterial pressure at brain-level (MAPbrain) and intracranial pressure (ICP), however, little is known about effects of moderate aerobic exercise on ICP. We hypothesize that moderate exercise does not increase ICP thereby facilitating the augmented cerebral blood flow and that a post-exercise decrease in ICP is a contributing mechanism to maintained cerebral blood flow during PEH.Non-invasive (N=14) and invasive (N=3) ICP recordings and cardiovascular parameters were measured upright and supine before, during, and after 30 minutes of seated moderate aerobic bicycle exercise. Exercise elevated MAPbrain from 68±4 to 82±7 mmHg (mean±SEM, P<0.05) without elevating ICP, thus increasing CPP (72±3 to 87±6 mmHg, P<0.05). Compared to before exercise, we found significant PEH with a decrease in MAPbrain of 5±3% (5 mmHg; P<0.05), predominantly driven by a 26±5% (P<0.0001) decrease in total peripheral resistance (TPR). Because post-exercise ICP decreased concomitantly by 58±20% (P<0.0001) CPP remained unchanged. Recovery of ICP towards baseline was similarly correlated to TPR-recovery (R2=0.92, P<0.001), all variables returned to baseline within one hour.Here, we show for the first time ICP during and following aerobic exercise and consequences for cerebral perfusion. Periodic PEH is cardio-vascular protective and has long-term benefits for hypertensive patients, here we suggest that post-exercise decreases in ICP could similarly be cerebo-protective and in part explain the long-term beneficial effects of exercise for cerebral health and cognition. This work was supported by NASA grant no 80NSSC19K0020 and the Novo Nordic Foundation grant no NNF15OC0019196 This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.
{"title":"Arterial and Intracranial Hypotension During and Following Exercise","authors":"L. Petersen","doi":"10.1152/physiol.2023.38.s1.5793685","DOIUrl":"https://doi.org/10.1152/physiol.2023.38.s1.5793685","url":null,"abstract":"Exercise induced arterial hypertension and post-exercise arterial hypotension (PEH) are well-described phenomena with direct impact on cerebral blood flow. Cerebral perfusion pressure is given by the difference between mean arterial pressure at brain-level (MAPbrain) and intracranial pressure (ICP), however, little is known about effects of moderate aerobic exercise on ICP. We hypothesize that moderate exercise does not increase ICP thereby facilitating the augmented cerebral blood flow and that a post-exercise decrease in ICP is a contributing mechanism to maintained cerebral blood flow during PEH.Non-invasive (N=14) and invasive (N=3) ICP recordings and cardiovascular parameters were measured upright and supine before, during, and after 30 minutes of seated moderate aerobic bicycle exercise. Exercise elevated MAPbrain from 68±4 to 82±7 mmHg (mean±SEM, P<0.05) without elevating ICP, thus increasing CPP (72±3 to 87±6 mmHg, P<0.05). Compared to before exercise, we found significant PEH with a decrease in MAPbrain of 5±3% (5 mmHg; P<0.05), predominantly driven by a 26±5% (P<0.0001) decrease in total peripheral resistance (TPR). Because post-exercise ICP decreased concomitantly by 58±20% (P<0.0001) CPP remained unchanged. Recovery of ICP towards baseline was similarly correlated to TPR-recovery (R2=0.92, P<0.001), all variables returned to baseline within one hour.Here, we show for the first time ICP during and following aerobic exercise and consequences for cerebral perfusion. Periodic PEH is cardio-vascular protective and has long-term benefits for hypertensive patients, here we suggest that post-exercise decreases in ICP could similarly be cerebo-protective and in part explain the long-term beneficial effects of exercise for cerebral health and cognition. This work was supported by NASA grant no 80NSSC19K0020 and the Novo Nordic Foundation grant no NNF15OC0019196 This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.","PeriodicalId":49694,"journal":{"name":"Physiology","volume":"20 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90371064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}