Pub Date : 2024-10-17eCollection Date: 2024-01-01DOI: 10.3389/fcell.2024.1491429
Erin M Craig, Francesca Oprea, Sajid Alam, Ania Grodsky, Kyle E Miller
While the structural organization and molecular biology of neurons are well characterized, the physical process of axonal elongation remains elusive. The classic view posited elongation occurs through the deposition of cytoskeletal elements in the growth cone at the tip of a stationary array of microtubules. Yet, recent studies reveal axonal microtubules and docked organelles flow forward in bulk in the elongating axons of Aplysia, chick sensory, rat hippocampal, and Drosophila neurons. Noting that the morphology, molecular components, and subcellular flow patterns of growth cones strongly resemble the leading edge of migrating cells and the polar regions of dividing cells, our working hypothesis is that axonal elongation utilizes the same physical mechanisms that drive cell crawling and cell division. As a test of that hypothesis, here we take experimental data sets of sub-cellular flow patterns in cells undergoing cytokinesis, mesenchymal migration, amoeboid migration, neuronal migration, and axonal elongation. We then apply active fluid theory to develop a biophysical model that describes the different sub-cellular flow profiles across these forms of motility and how this generates cell motility under low Reynolds numbers. The modeling suggests that mechanisms for generating motion are shared across these processes, and differences arise through modifications of sub-cellular adhesion patterns and the profiles of internal force generation. Collectively, this work suggests that ameboid and mesenchymal cell crawling may have arisen from processes that first developed to support cell division, that growth cone motility and cell crawling are closely related, and that neuronal migration and axonal elongation are fundamentally similar, differing primarily in the motion and strength of adhesion under the cell body.
{"title":"A simple active fluid model unites cytokinesis, cell crawling, and axonal outgrowth.","authors":"Erin M Craig, Francesca Oprea, Sajid Alam, Ania Grodsky, Kyle E Miller","doi":"10.3389/fcell.2024.1491429","DOIUrl":"10.3389/fcell.2024.1491429","url":null,"abstract":"<p><p>While the structural organization and molecular biology of neurons are well characterized, the physical process of axonal elongation remains elusive. The classic view posited elongation occurs through the deposition of cytoskeletal elements in the growth cone at the tip of a stationary array of microtubules. Yet, recent studies reveal axonal microtubules and docked organelles flow forward in bulk in the elongating axons of <i>Aplysia</i>, chick sensory, rat hippocampal, and <i>Drosophila</i> neurons. Noting that the morphology, molecular components, and subcellular flow patterns of growth cones strongly resemble the leading edge of migrating cells and the polar regions of dividing cells, our working hypothesis is that axonal elongation utilizes the same physical mechanisms that drive cell crawling and cell division. As a test of that hypothesis, here we take experimental data sets of sub-cellular flow patterns in cells undergoing cytokinesis, mesenchymal migration, amoeboid migration, neuronal migration, and axonal elongation. We then apply active fluid theory to develop a biophysical model that describes the different sub-cellular flow profiles across these forms of motility and how this generates cell motility under low Reynolds numbers. The modeling suggests that mechanisms for generating motion are shared across these processes, and differences arise through modifications of sub-cellular adhesion patterns and the profiles of internal force generation. Collectively, this work suggests that ameboid and mesenchymal cell crawling may have arisen from processes that first developed to support cell division, that growth cone motility and cell crawling are closely related, and that neuronal migration and axonal elongation are fundamentally similar, differing primarily in the motion and strength of adhesion under the cell body.</p>","PeriodicalId":12448,"journal":{"name":"Frontiers in Cell and Developmental Biology","volume":null,"pages":null},"PeriodicalIF":4.6,"publicationDate":"2024-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11524947/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142557569","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}
Pub Date : 2024-10-17eCollection Date: 2024-01-01DOI: 10.3389/fcell.2024.1472906
Ashley Harman, Tracy M Bryan
Telomeres are the protective caps at the ends of linear chromosomes of eukaryotic organisms. Telomere binding proteins, including the six components of the complex known as shelterin, mediate the protective function of telomeres. They do this by suppressing many arms of the canonical DNA damage response, thereby preventing inappropriate fusion, resection and recombination of telomeres. One way this is achieved is by facilitation of DNA replication through telomeres, thus protecting against a "replication stress" response and activation of the master kinase ATR. On the other hand, DNA damage responses, including replication stress and ATR, serve a positive role at telomeres, acting as a trigger for recruitment of the telomere-elongating enzyme telomerase to counteract telomere loss. We postulate that repression of telomeric replication stress is a shared mechanism of control of telomerase recruitment and telomere length, common to several core telomere binding proteins including TRF1, POT1 and CTC1. The mechanisms by which replication stress and ATR cause recruitment of telomerase are not fully elucidated, but involve formation of nuclear actin filaments that serve as anchors for stressed telomeres. Perturbed control of telomeric replication stress by mutations in core telomere binding proteins can therefore cause the deregulation of telomere length control characteristic of diseases such as cancer and telomere biology disorders.
端粒是真核生物线性染色体末端的保护帽。端粒结合蛋白,包括称为 "庇护蛋白 "的复合体的六个组成部分,介导端粒的保护功能。它们通过抑制典型 DNA 损伤反应的许多环节来实现这一功能,从而防止端粒的不适当融合、切除和重组。其中一种方法是通过端粒促进DNA复制,从而防止 "复制压力 "反应和主激酶ATR的激活。另一方面,DNA损伤反应(包括复制应激和ATR)在端粒上发挥着积极作用,可触发端粒延长酶端粒酶的招募,从而抵消端粒的丢失。我们推测,端粒复制应激的抑制是端粒酶招募和端粒长度控制的共同机制,是包括TRF1、POT1和CTC1在内的几种核心端粒结合蛋白的共同机制。复制胁迫和 ATR 导致端粒酶招募的机制尚未完全阐明,但涉及作为受胁迫端粒锚的核肌动蛋白丝的形成。因此,核心端粒结合蛋白的突变导致端粒复制压力控制失调,可引起端粒长度控制失调,这是癌症和端粒生物学紊乱等疾病的特征。
{"title":"Telomere maintenance and the DNA damage response: a paradoxical alliance.","authors":"Ashley Harman, Tracy M Bryan","doi":"10.3389/fcell.2024.1472906","DOIUrl":"10.3389/fcell.2024.1472906","url":null,"abstract":"<p><p>Telomeres are the protective caps at the ends of linear chromosomes of eukaryotic organisms. Telomere binding proteins, including the six components of the complex known as shelterin, mediate the protective function of telomeres. They do this by suppressing many arms of the canonical DNA damage response, thereby preventing inappropriate fusion, resection and recombination of telomeres. One way this is achieved is by facilitation of DNA replication through telomeres, thus protecting against a \"replication stress\" response and activation of the master kinase ATR. On the other hand, DNA damage responses, including replication stress and ATR, serve a positive role at telomeres, acting as a trigger for recruitment of the telomere-elongating enzyme telomerase to counteract telomere loss. We postulate that repression of telomeric replication stress is a shared mechanism of control of telomerase recruitment and telomere length, common to several core telomere binding proteins including TRF1, POT1 and CTC1. The mechanisms by which replication stress and ATR cause recruitment of telomerase are not fully elucidated, but involve formation of nuclear actin filaments that serve as anchors for stressed telomeres. Perturbed control of telomeric replication stress by mutations in core telomere binding proteins can therefore cause the deregulation of telomere length control characteristic of diseases such as cancer and telomere biology disorders.</p>","PeriodicalId":12448,"journal":{"name":"Frontiers in Cell and Developmental Biology","volume":null,"pages":null},"PeriodicalIF":4.6,"publicationDate":"2024-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11524846/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142557573","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}
Pub Date : 2024-10-17eCollection Date: 2024-01-01DOI: 10.3389/fcell.2024.1492821
Xuan Wang, Jiaying Guo, Qiangfu Dai
Systemic sclerosis (SSc) is a complex autoimmune disease with clinical symptoms of vascular damage, immune disorders, and fibrosis, presenting significant treatment challenges and limited therapeutic options. Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) have been demonstrated in numerous studies as more effective than MSCs in treating autoimmune diseases. Recent studies demonstrate that MSC-EVs can significantly ameliorate the symptoms of SSc and mitigate pathological changes such as vascular injury, immune dysregulation, and fibrosis. These findings underscore the promising therapeutic potential of MSC-EVs in the treatment of SSc. MSC-EVs promote angiogenesis, modulate immune dysfunction, and combat fibrosis. This article summarizes the therapeutic applications and possible mechanisms of MSC-EVs for SSc, thereby offering a novel therapeutic direction for the treatment of SSc.
{"title":"Mesenchymal stem cell-derived extracellular vesicles in systemic sclerosis: role and therapeutic directions.","authors":"Xuan Wang, Jiaying Guo, Qiangfu Dai","doi":"10.3389/fcell.2024.1492821","DOIUrl":"10.3389/fcell.2024.1492821","url":null,"abstract":"<p><p>Systemic sclerosis (SSc) is a complex autoimmune disease with clinical symptoms of vascular damage, immune disorders, and fibrosis, presenting significant treatment challenges and limited therapeutic options. Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) have been demonstrated in numerous studies as more effective than MSCs in treating autoimmune diseases. Recent studies demonstrate that MSC-EVs can significantly ameliorate the symptoms of SSc and mitigate pathological changes such as vascular injury, immune dysregulation, and fibrosis. These findings underscore the promising therapeutic potential of MSC-EVs in the treatment of SSc. MSC-EVs promote angiogenesis, modulate immune dysfunction, and combat fibrosis. This article summarizes the therapeutic applications and possible mechanisms of MSC-EVs for SSc, thereby offering a novel therapeutic direction for the treatment of SSc.</p>","PeriodicalId":12448,"journal":{"name":"Frontiers in Cell and Developmental Biology","volume":null,"pages":null},"PeriodicalIF":4.6,"publicationDate":"2024-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11524835/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142557572","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}
Pub Date : 2024-10-16eCollection Date: 2024-01-01DOI: 10.3389/fcell.2024.1453566
Corin Stansfield, Kevin J Parsons
Efforts to reconcile development and evolution have demonstrated that development is biased, with phenotypic variation being more readily produced in certain directions. However, how this "developmental bias" can influence micro- and macroevolution is poorly understood. In this review, we demonstrate that defining features of adaptive radiations suggest a role for developmental bias in driving adaptive divergence. These features are i) common ancestry of developmental systems; ii) rapid evolution along evolutionary "lines of least resistance;" iii) the subsequent repeated and parallel evolution of ecotypes; and iv) evolutionary change "led" by biased phenotypic plasticity upon exposure to novel environments. Drawing on empirical and theoretical data, we highlight the reciprocal relationship between development and selection as a key driver of evolutionary change, with development biasing what variation is exposed to selection, and selection acting to mold these biases to align with the adaptive landscape. Our central thesis is that developmental biases are both the causes and consequences of adaptive radiation and divergence. We argue throughout that incorporating development and developmental bias into our thinking can help to explain the exaggerated rate and scale of evolutionary processes that characterize adaptive radiations, and that this can be best achieved by using an eco-evo-devo framework incorporating evolutionary biology, development, and ecology. Such a research program would demonstrate that development is not merely a force that imposes constraints on evolution, but rather directs and is directed by evolutionary forces. We round out this review by highlighting key gaps in our understanding and suggest further research programs that can help to resolve these issues.
{"title":"Developmental bias as a cause and consequence of adaptive radiation and divergence.","authors":"Corin Stansfield, Kevin J Parsons","doi":"10.3389/fcell.2024.1453566","DOIUrl":"10.3389/fcell.2024.1453566","url":null,"abstract":"<p><p>Efforts to reconcile development and evolution have demonstrated that development is biased, with phenotypic variation being more readily produced in certain directions. However, how this \"developmental bias\" can influence micro- and macroevolution is poorly understood. In this review, we demonstrate that defining features of adaptive radiations suggest a role for developmental bias in driving adaptive divergence. These features are i) common ancestry of developmental systems; ii) rapid evolution along evolutionary \"lines of least resistance;\" iii) the subsequent repeated and parallel evolution of ecotypes; and iv) evolutionary change \"led\" by biased phenotypic plasticity upon exposure to novel environments. Drawing on empirical and theoretical data, we highlight the reciprocal relationship between development and selection as a key driver of evolutionary change, with development biasing what variation is exposed to selection, and selection acting to mold these biases to align with the adaptive landscape. Our central thesis is that developmental biases are both the causes and consequences of adaptive radiation and divergence. We argue throughout that incorporating development and developmental bias into our thinking can help to explain the exaggerated rate and scale of evolutionary processes that characterize adaptive radiations, and that this can be best achieved by using an eco-evo-devo framework incorporating evolutionary biology, development, and ecology. Such a research program would demonstrate that development is not merely a force that imposes constraints on evolution, but rather directs and is directed by evolutionary forces. We round out this review by highlighting key gaps in our understanding and suggest further research programs that can help to resolve these issues.</p>","PeriodicalId":12448,"journal":{"name":"Frontiers in Cell and Developmental Biology","volume":null,"pages":null},"PeriodicalIF":4.6,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11521891/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142544719","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}
Pub Date : 2024-10-16eCollection Date: 2024-01-01DOI: 10.3389/fcell.2024.1469541
Shuifen Sun, Linping Wang, Qisheng Tang, Jialian Yi, Xin Yu, Yu Cao, Lihong Jiang, Jie Liu
Background: Mesenchymal stem cells (MSCs) are safe and effective in treating myocardial infarction (MI) and have broad application prospects. However, the heterogeneity of MSCs may affect their therapeutic effect on the disease. We recently found that MSCs derived from different segments of the same umbilical cord (UC) showed significant difference in the expression of genes that are related to heart development and injury repair. We therefore hypothesized that those MSCs with high expression of above genes are more effective to treat MI and tested it in this study.
Methods: MSCs were isolated from 3 cm-long segments of the maternal, middle and fetal segments of the UC (maternal-MSCs, middle-MSCs and fetal-MSCs, respectively). RNA-seq was used to analyze and compare the transcriptomes. We verified the effects of MSCs on oxygen-glucose deprivation (OGD)-induced cardiomyocyte apoptosis in vitro. In vivo, a rat MI model was established by ligating the left anterior descending coronary artery, and MSCs were injected into the myocardium surrounding the MI site. The therapeutic effects of MSCs derived from different segments of the UC were evaluated by examining cardiac function, histopathology, cardiomyocyte apoptosis, and angiogenesis.
Results: Compared to fetal-MSCs and middle-MSCs, maternal-MSCs exhibited significantly higher expression of genes that are associated with heart development, such as GATA-binding protein 4 (GATA4), and myocardin (MYOCD). Coculture with maternal-MSCs reduced OGD-induced cardiomyocyte apoptosis. In rats with MI, maternal-MSCs significantly restored cardiac contractile function and reduced the infarct size. Mechanistic experiments revealed that maternal-MSCs exerted cardioprotective effects by decreasing cardiomyocyte apoptosis, and promoting angiogenesis.
Conclusion: Our data demonstrated that maternal segment-derived MSCs were a superior cell source for regenerative repair after MI. Segmental localization of the entire UC when isolating hUCMSCs was necessary to improve the effectiveness of clinical applications.
{"title":"Myocardial infarction in rats was alleviated by MSCs derived from the maternal segment of the human umbilical cord.","authors":"Shuifen Sun, Linping Wang, Qisheng Tang, Jialian Yi, Xin Yu, Yu Cao, Lihong Jiang, Jie Liu","doi":"10.3389/fcell.2024.1469541","DOIUrl":"10.3389/fcell.2024.1469541","url":null,"abstract":"<p><strong>Background: </strong>Mesenchymal stem cells (MSCs) are safe and effective in treating myocardial infarction (MI) and have broad application prospects. However, the heterogeneity of MSCs may affect their therapeutic effect on the disease. We recently found that MSCs derived from different segments of the same umbilical cord (UC) showed significant difference in the expression of genes that are related to heart development and injury repair. We therefore hypothesized that those MSCs with high expression of above genes are more effective to treat MI and tested it in this study.</p><p><strong>Methods: </strong>MSCs were isolated from 3 cm-long segments of the maternal, middle and fetal segments of the UC (maternal-MSCs, middle-MSCs and fetal-MSCs, respectively). RNA-seq was used to analyze and compare the transcriptomes. We verified the effects of MSCs on oxygen-glucose deprivation (OGD)-induced cardiomyocyte apoptosis <i>in vitro</i>. <i>In vivo</i>, a rat MI model was established by ligating the left anterior descending coronary artery, and MSCs were injected into the myocardium surrounding the MI site. The therapeutic effects of MSCs derived from different segments of the UC were evaluated by examining cardiac function, histopathology, cardiomyocyte apoptosis, and angiogenesis.</p><p><strong>Results: </strong>Compared to fetal-MSCs and middle-MSCs, maternal-MSCs exhibited significantly higher expression of genes that are associated with heart development, such as GATA-binding protein 4 (GATA4), and myocardin (MYOCD). Coculture with maternal-MSCs reduced OGD-induced cardiomyocyte apoptosis. In rats with MI, maternal-MSCs significantly restored cardiac contractile function and reduced the infarct size. Mechanistic experiments revealed that maternal-MSCs exerted cardioprotective effects by decreasing cardiomyocyte apoptosis, and promoting angiogenesis.</p><p><strong>Conclusion: </strong>Our data demonstrated that maternal segment-derived MSCs were a superior cell source for regenerative repair after MI. Segmental localization of the entire UC when isolating hUCMSCs was necessary to improve the effectiveness of clinical applications.</p>","PeriodicalId":12448,"journal":{"name":"Frontiers in Cell and Developmental Biology","volume":null,"pages":null},"PeriodicalIF":4.6,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11521943/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142544722","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}
Rho guanine nucleotide exchange factors (RhoGEFs) comprise a wide range of proteins with a common domain responsible for the activation of the Rho family of small GTPases and various domains in other regions. The evolutionary divergence of RhoGEFs enables actin cytoskeletal reorganization, leading to complex cellular responses in higher organisms. In this review, we address the involvement of RhoGEFs in the mechanical stress response of mammalian cells. The cellular mechanical stress response is essential for the proper and orderly regulation of cell populations, including the maintenance of homeostasis, tissue morphogenesis, and adaptation to the mechanical environment. In particular, this review focuses on the recent findings regarding the Dbl family of RhoGEFs involved in mechanical stress responses at the cell-cell and cell-substrate adhesion sites, and their molecular mechanisms underlying actin cytoskeleton remodeling and signal transduction.
{"title":"Roles of the Dbl family of RhoGEFs in mechanotransduction - a review.","authors":"Kazumasa Ohashi, Aoi Kunitomi, Shuhei Chiba, Kensaku Mizuno","doi":"10.3389/fcell.2024.1485725","DOIUrl":"10.3389/fcell.2024.1485725","url":null,"abstract":"<p><p>Rho guanine nucleotide exchange factors (RhoGEFs) comprise a wide range of proteins with a common domain responsible for the activation of the Rho family of small GTPases and various domains in other regions. The evolutionary divergence of RhoGEFs enables actin cytoskeletal reorganization, leading to complex cellular responses in higher organisms. In this review, we address the involvement of RhoGEFs in the mechanical stress response of mammalian cells. The cellular mechanical stress response is essential for the proper and orderly regulation of cell populations, including the maintenance of homeostasis, tissue morphogenesis, and adaptation to the mechanical environment. In particular, this review focuses on the recent findings regarding the Dbl family of RhoGEFs involved in mechanical stress responses at the cell-cell and cell-substrate adhesion sites, and their molecular mechanisms underlying actin cytoskeleton remodeling and signal transduction.</p>","PeriodicalId":12448,"journal":{"name":"Frontiers in Cell and Developmental Biology","volume":null,"pages":null},"PeriodicalIF":4.6,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11521908/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142544724","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}
Pub Date : 2024-10-16eCollection Date: 2024-01-01DOI: 10.3389/fcell.2024.1467799
Brandon A Coughlin, Barbara Christian, Brett Trombley, Susanne Mohr
Introduction: Inflammation and cell death play an important role in the pathogenesis of diabetic retinopathy. Previously we observed sustained activation of pro-inflammatory caspase-1 in retinas of diabetic animals and patients. In this study, we aimed to look at mechanisms underlying chronic caspase-1 activation in vitro and in vivo.
Methods: Non-diabetic and diabetic wild type and IL-1 receptor (IL-1R1) knockout mice were used for in vivo experiments. Diabetes was induced using STZ (streptozotocin). Human Müller cells were used for in vitro studies. Cells were treated with either 5 mM or 25 mM glucose or interleukin-1beta (IL-1β) in the presence or absence of IL-1 receptor antagonist (IL-1ra) or siRNA against RIP2 (receptor interacting protein-2) for up to 96 h. Outcome measurements to assess Müller cell functions included measurements of caspase-1 activity using a fluorescence peptide substrate, production of IL-1β by Elisa, and cell death using trypan blue exclusion assays.
Results: Our in vivo results demonstrate that caspase-1 activation progresses from an IL-1R1 independent mechanism at 10 weeks of diabetes to an IL-1R1 dependent mechanism at 20 weeks indicating that feedback through IL-1R1 is crucial for sustained caspase-1 activity in retinas of mice. A similar hyperglycemia-mediated caspase-1/IL-1β/IL-1R1 feedback signaling was detected in vitro in human Müller cells which was prevented by treatment with IL-1ra. Our data also indicate that hyperglycemia induces caspase-1 activation initially but IL-1β sustains caspase-1 activation via caspase-1/IL-1β/IL-1R1 feedback and we identified RIP2 as mediator for both hyperglycemia- and IL-1β-induced caspase-1 activation. Activation of caspase-1/IL-1β/IL-1R1 feedback signaling caused Müller cell death which was prevented by RIP2 knockdown.
Discussion: We conclude that any intervention in caspase-1/IL-1β/IL-1R1 feedback signaling presents novel therapeutic options for the treatment of diabetic retinopathy.
{"title":"Interleukin-1 receptor-dependent and -independent caspase-1 activity in retinal cells mediated by receptor interacting protein 2.","authors":"Brandon A Coughlin, Barbara Christian, Brett Trombley, Susanne Mohr","doi":"10.3389/fcell.2024.1467799","DOIUrl":"10.3389/fcell.2024.1467799","url":null,"abstract":"<p><strong>Introduction: </strong>Inflammation and cell death play an important role in the pathogenesis of diabetic retinopathy. Previously we observed sustained activation of pro-inflammatory caspase-1 in retinas of diabetic animals and patients. In this study, we aimed to look at mechanisms underlying chronic caspase-1 activation <i>in vitro</i> and <i>in vivo</i>.</p><p><strong>Methods: </strong>Non-diabetic and diabetic wild type and IL-1 receptor (IL-1R1) knockout mice were used for <i>in vivo</i> experiments. Diabetes was induced using STZ (streptozotocin). Human Müller cells were used for <i>in vitro</i> studies. Cells were treated with either 5 mM or 25 mM glucose or interleukin-1beta (IL-1β) in the presence or absence of IL-1 receptor antagonist (IL-1ra) or siRNA against RIP2 (receptor interacting protein-2) for up to 96 h. Outcome measurements to assess Müller cell functions included measurements of caspase-1 activity using a fluorescence peptide substrate, production of IL-1β by Elisa, and cell death using trypan blue exclusion assays.</p><p><strong>Results: </strong>Our <i>in vivo</i> results demonstrate that caspase-1 activation progresses from an IL-1R1 independent mechanism at 10 weeks of diabetes to an IL-1R1 dependent mechanism at 20 weeks indicating that feedback through IL-1R1 is crucial for sustained caspase-1 activity in retinas of mice. A similar hyperglycemia-mediated caspase-1/IL-1β/IL-1R1 feedback signaling was detected <i>in vitro</i> in human Müller cells which was prevented by treatment with IL-1ra. Our data also indicate that hyperglycemia induces caspase-1 activation initially but IL-1β sustains caspase-1 activation via caspase-1/IL-1β/IL-1R1 feedback and we identified RIP2 as mediator for both hyperglycemia- and IL-1β-induced caspase-1 activation. Activation of caspase-1/IL-1β/IL-1R1 feedback signaling caused Müller cell death which was prevented by RIP2 knockdown.</p><p><strong>Discussion: </strong>We conclude that any intervention in caspase-1/IL-1β/IL-1R1 feedback signaling presents novel therapeutic options for the treatment of diabetic retinopathy.</p>","PeriodicalId":12448,"journal":{"name":"Frontiers in Cell and Developmental Biology","volume":null,"pages":null},"PeriodicalIF":4.6,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11525982/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142557571","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}
Pub Date : 2024-10-16eCollection Date: 2024-01-01DOI: 10.3389/fcell.2024.1461581
Christian Stoess, Aleksandra Leszczynska, Lin Kui, Ariel E Feldstein
[This corrects the article DOI: 10.3389/fcell.2023.1218807.].
[此处更正了文章 DOI:10.3389/fcell.2023.1218807]。
{"title":"Corrigendum: Pyroptosis and gasdermins-Emerging insights and therapeutic opportunities in metabolic dysfunction-associated steatohepatitis.","authors":"Christian Stoess, Aleksandra Leszczynska, Lin Kui, Ariel E Feldstein","doi":"10.3389/fcell.2024.1461581","DOIUrl":"https://doi.org/10.3389/fcell.2024.1461581","url":null,"abstract":"<p><p>[This corrects the article DOI: 10.3389/fcell.2023.1218807.].</p>","PeriodicalId":12448,"journal":{"name":"Frontiers in Cell and Developmental Biology","volume":null,"pages":null},"PeriodicalIF":4.6,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11522226/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142544718","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}
Pub Date : 2024-10-16eCollection Date: 2024-01-01DOI: 10.3389/fcell.2024.1480217
Min Wang, Xiaojuan Liu, Yin Fang, Qintong Li
Individuals with neurodevelopmental disorders (NDDs) are frequently diagnosed with comorbidities in other organs, indicating that NDD risk genes may have extra-cerebral functions. The engineered mouse models are pivotal in understanding the functions of candidate NDD genes. Here, we report that Emx1-Cre and nestin-Cre mouse strains, the popular tools to study brain development, also exhibit recombination activity in the kidney. We find that both Emx1-Cre and nestin-Cre can drive recombination in epithelial cells lining proximal and distal convoluted tubules of the nephron. Additionally, nestin-Cre drives recombination in the glomerulus of the nephron. Furthermore, we use Emx1-Cre and nestin-Cre to knock out Larp7, a gene linked to a human NDD called Alazami syndrome. We find that Larp7 knockout using nestin-Cre, but not Emx1-Cre, results in elevated blood urea nitrogen. This result suggests a compromised kidney function, reminiscent of recently revealed renal anomalies in Alazami syndrome patients. Many genes have been knocked out using Emx1-Cre and nestin-Cre to study their roles during embryonic neurogenesis. It will be of great interest to reinvestigate whether the renal development and function is affected in these existing mouse models.
{"title":"Extra-cerebral recombination activity of Emx1-Cre and nestin-Cre in the kidney.","authors":"Min Wang, Xiaojuan Liu, Yin Fang, Qintong Li","doi":"10.3389/fcell.2024.1480217","DOIUrl":"10.3389/fcell.2024.1480217","url":null,"abstract":"<p><p>Individuals with neurodevelopmental disorders (NDDs) are frequently diagnosed with comorbidities in other organs, indicating that NDD risk genes may have extra-cerebral functions. The engineered mouse models are pivotal in understanding the functions of candidate NDD genes. Here, we report that Emx1-Cre and nestin-Cre mouse strains, the popular tools to study brain development, also exhibit recombination activity in the kidney. We find that both Emx1-Cre and nestin-Cre can drive recombination in epithelial cells lining proximal and distal convoluted tubules of the nephron. Additionally, nestin-Cre drives recombination in the glomerulus of the nephron. Furthermore, we use Emx1-Cre and nestin-Cre to knock out <i>Larp7</i>, a gene linked to a human NDD called Alazami syndrome. We find that <i>Larp7</i> knockout using nestin-Cre, but not Emx1-Cre, results in elevated blood urea nitrogen. This result suggests a compromised kidney function, reminiscent of recently revealed renal anomalies in Alazami syndrome patients. Many genes have been knocked out using Emx1-Cre and nestin-Cre to study their roles during embryonic neurogenesis. It will be of great interest to reinvestigate whether the renal development and function is affected in these existing mouse models.</p>","PeriodicalId":12448,"journal":{"name":"Frontiers in Cell and Developmental Biology","volume":null,"pages":null},"PeriodicalIF":4.6,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11521858/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142550053","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}
Pub Date : 2024-10-16eCollection Date: 2024-01-01DOI: 10.3389/fcell.2024.1494398
Yong Kang Jia, Yang Yu, Li Guan
Embryonic stem cells (ESCs) sourced from the inner cell mass of blastocysts, are akin to this tissue in function but lack the capacity to form all extraembryonic structures. mESCs are transient cell populations that express high levels of transcripts characteristic of 2-cell (2C) embryos and are identified as "2-cell-like cells" (2CLCs). Previous studies have shown that 2CLCs can contribute to both embryonic and extraembryonic tissues upon reintroduction into early embryos. Approximately 1% of mESCs dynamically transition from pluripotent mESCs into 2CLCs. Nevertheless, the scarcity of mammalian embryos presents a significant challenge to the molecular characterization of totipotent cells. To date, Previous studies have explored various methods for reprogramming pluripotent cells into totipotent cells. While there is a good understanding of the molecular regulatory network maintaining ES pluripotency, the process by which pluripotent ESCs reprogram into totipotent cells and the associated molecular mechanisms of totipotent regulation remain poorly understood. This review synthesizes recent insights into the regulatory pathways of ESC reprogramming into 2CLC, exploring molecular mechanisms modulated by transcriptional regulators, small molecules, and epigenetic changes. The objective is to construct a theoretical framework for the field of researchers.
{"title":"Advances in understanding the regulation of pluripotency fate transition in embryonic stem cells.","authors":"Yong Kang Jia, Yang Yu, Li Guan","doi":"10.3389/fcell.2024.1494398","DOIUrl":"10.3389/fcell.2024.1494398","url":null,"abstract":"<p><p>Embryonic stem cells (ESCs) sourced from the inner cell mass of blastocysts, are akin to this tissue in function but lack the capacity to form all extraembryonic structures. mESCs are transient cell populations that express high levels of transcripts characteristic of 2-cell (2C) embryos and are identified as \"2-cell-like cells\" (2CLCs). Previous studies have shown that 2CLCs can contribute to both embryonic and extraembryonic tissues upon reintroduction into early embryos. Approximately 1% of mESCs dynamically transition from pluripotent mESCs into 2CLCs. Nevertheless, the scarcity of mammalian embryos presents a significant challenge to the molecular characterization of totipotent cells. To date, Previous studies have explored various methods for reprogramming pluripotent cells into totipotent cells. While there is a good understanding of the molecular regulatory network maintaining ES pluripotency, the process by which pluripotent ESCs reprogram into totipotent cells and the associated molecular mechanisms of totipotent regulation remain poorly understood. This review synthesizes recent insights into the regulatory pathways of ESC reprogramming into 2CLC, exploring molecular mechanisms modulated by transcriptional regulators, small molecules, and epigenetic changes. The objective is to construct a theoretical framework for the field of researchers.</p>","PeriodicalId":12448,"journal":{"name":"Frontiers in Cell and Developmental Biology","volume":null,"pages":null},"PeriodicalIF":4.6,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11521825/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142544715","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}