Annan Chen, Jian Zhang, Zhixin Yan, Yufei Lu, Weize Chen, Yingxue Sun, Qiuyu Gu, Fang Li, Yan Yang, Shanfang Qiu, Xueping Lin, Dong Zhang, Jie Teng, Yi Fang, Bo Shen, Nana Song, Xiaoqiang Ding
{"title":"酸性预处理通过局灶粘附激酶依赖性激活钠氢交换子1的动态磷酸化诱导细胞内酸适应以保护肾损伤。","authors":"Annan Chen, Jian Zhang, Zhixin Yan, Yufei Lu, Weize Chen, Yingxue Sun, Qiuyu Gu, Fang Li, Yan Yang, Shanfang Qiu, Xueping Lin, Dong Zhang, Jie Teng, Yi Fang, Bo Shen, Nana Song, Xiaoqiang Ding","doi":"10.1186/s12964-024-01773-w","DOIUrl":null,"url":null,"abstract":"<p><strong>Background: </strong>Disruptions in intracellular pH (pH<sub>i</sub>) homeostasis, causing deviations from the physiological range, can damage renal epithelial cells. However, the existence of an adaptive mechanism to restore pH<sub>i</sub> to normalcy remains unclear. Early research identified H<sup>+</sup> as a critical mediator of ischemic preconditioning (IPC), leading to the concept of acidic preconditioning (AP). This concept proposes that short-term, repetitive acidic stimulation can enhance a cell's capacity to withstand subsequent adverse stress. While AP has demonstrated protective effects in various ischemia-reperfusion (I/R) injury models, its application in kidney injury remains largely unexplored.</p><p><strong>Methods: </strong>An AP model was established in human kidney (HK2) cells by treating them with an acidic medium for 12 h, followed by a recovery period with a normal medium for 6 h. To induce hypoxia/reoxygenation (H/R) injury, HK2 cells were subjected to hypoxia for 24 h and reoxygenation for 1 h. In vivo, a mouse model of IPC was established by clamping the bilateral renal pedicles for 15 min, followed by reperfusion for 4 days. Conversely, the I/R model involved clamping the bilateral renal pedicles for 35 min and reperfusion for 24 h. Western blotting was employed to evaluate the expression levels of cleaved caspase 3, cleaved caspase 9, NHE1, KIM1, FAK, and NOX4. A pH-sensitive fluorescent probe was used to measure pH<sub>i</sub>, while a Hemin/CNF microelectrode monitored kidney tissue pH. Immunofluorescence staining was performed to visualize the localization of NHE1, NOX4, and FAK, along with the actin cytoskeleton structure in HK2 cells. Cell adhesion and scratch assays were conducted to assess cell motility.</p><p><strong>Results: </strong>Our findings demonstrated that AP could effectively mitigate H/R injury in HK2 cells. This protective effect and the maintenance of pH<sub>i</sub> homeostasis by AP involved the upregulation of Na<sup>+</sup>/H<sup>+</sup> exchanger 1 (NHE1) expression and activity. The activity of NHE1 was regulated by dynamic changes in pH<sub>i</sub>-dependent phosphorylation of Focal Adhesion Kinase (FAK) at Y397. This process was associated with NOX4-mediated reactive oxygen species (ROS) production. Furthermore, AP induced the co-localization of FAK, NOX4, and NHE1 in focal adhesions, promoting cytoskeletal remodeling and enhancing cell adhesion and migration capabilities.</p><p><strong>Conclusions: </strong>This study provides compelling evidence that AP maintains pH<sub>i</sub> homeostasis and promotes cytoskeletal remodeling through FAK/NOX4/NHE1 signaling. This signaling pathway ultimately contributes to alleviated H/R injury in HK2 cells.</p>","PeriodicalId":55268,"journal":{"name":"Cell Communication and Signaling","volume":null,"pages":null},"PeriodicalIF":8.2000,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11308338/pdf/","citationCount":"0","resultStr":"{\"title\":\"Acidic preconditioning induced intracellular acid adaptation to protect renal injury via dynamic phosphorylation of focal adhesion kinase-dependent activation of sodium hydrogen exchanger 1.\",\"authors\":\"Annan Chen, Jian Zhang, Zhixin Yan, Yufei Lu, Weize Chen, Yingxue Sun, Qiuyu Gu, Fang Li, Yan Yang, Shanfang Qiu, Xueping Lin, Dong Zhang, Jie Teng, Yi Fang, Bo Shen, Nana Song, Xiaoqiang Ding\",\"doi\":\"10.1186/s12964-024-01773-w\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><strong>Background: </strong>Disruptions in intracellular pH (pH<sub>i</sub>) homeostasis, causing deviations from the physiological range, can damage renal epithelial cells. However, the existence of an adaptive mechanism to restore pH<sub>i</sub> to normalcy remains unclear. Early research identified H<sup>+</sup> as a critical mediator of ischemic preconditioning (IPC), leading to the concept of acidic preconditioning (AP). This concept proposes that short-term, repetitive acidic stimulation can enhance a cell's capacity to withstand subsequent adverse stress. While AP has demonstrated protective effects in various ischemia-reperfusion (I/R) injury models, its application in kidney injury remains largely unexplored.</p><p><strong>Methods: </strong>An AP model was established in human kidney (HK2) cells by treating them with an acidic medium for 12 h, followed by a recovery period with a normal medium for 6 h. To induce hypoxia/reoxygenation (H/R) injury, HK2 cells were subjected to hypoxia for 24 h and reoxygenation for 1 h. In vivo, a mouse model of IPC was established by clamping the bilateral renal pedicles for 15 min, followed by reperfusion for 4 days. Conversely, the I/R model involved clamping the bilateral renal pedicles for 35 min and reperfusion for 24 h. Western blotting was employed to evaluate the expression levels of cleaved caspase 3, cleaved caspase 9, NHE1, KIM1, FAK, and NOX4. A pH-sensitive fluorescent probe was used to measure pH<sub>i</sub>, while a Hemin/CNF microelectrode monitored kidney tissue pH. Immunofluorescence staining was performed to visualize the localization of NHE1, NOX4, and FAK, along with the actin cytoskeleton structure in HK2 cells. Cell adhesion and scratch assays were conducted to assess cell motility.</p><p><strong>Results: </strong>Our findings demonstrated that AP could effectively mitigate H/R injury in HK2 cells. This protective effect and the maintenance of pH<sub>i</sub> homeostasis by AP involved the upregulation of Na<sup>+</sup>/H<sup>+</sup> exchanger 1 (NHE1) expression and activity. The activity of NHE1 was regulated by dynamic changes in pH<sub>i</sub>-dependent phosphorylation of Focal Adhesion Kinase (FAK) at Y397. This process was associated with NOX4-mediated reactive oxygen species (ROS) production. Furthermore, AP induced the co-localization of FAK, NOX4, and NHE1 in focal adhesions, promoting cytoskeletal remodeling and enhancing cell adhesion and migration capabilities.</p><p><strong>Conclusions: </strong>This study provides compelling evidence that AP maintains pH<sub>i</sub> homeostasis and promotes cytoskeletal remodeling through FAK/NOX4/NHE1 signaling. This signaling pathway ultimately contributes to alleviated H/R injury in HK2 cells.</p>\",\"PeriodicalId\":55268,\"journal\":{\"name\":\"Cell Communication and Signaling\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":8.2000,\"publicationDate\":\"2024-08-08\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11308338/pdf/\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Cell Communication and Signaling\",\"FirstCategoryId\":\"99\",\"ListUrlMain\":\"https://doi.org/10.1186/s12964-024-01773-w\",\"RegionNum\":2,\"RegionCategory\":\"生物学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"CELL BIOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Cell Communication and Signaling","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1186/s12964-024-01773-w","RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CELL BIOLOGY","Score":null,"Total":0}
Acidic preconditioning induced intracellular acid adaptation to protect renal injury via dynamic phosphorylation of focal adhesion kinase-dependent activation of sodium hydrogen exchanger 1.
Background: Disruptions in intracellular pH (pHi) homeostasis, causing deviations from the physiological range, can damage renal epithelial cells. However, the existence of an adaptive mechanism to restore pHi to normalcy remains unclear. Early research identified H+ as a critical mediator of ischemic preconditioning (IPC), leading to the concept of acidic preconditioning (AP). This concept proposes that short-term, repetitive acidic stimulation can enhance a cell's capacity to withstand subsequent adverse stress. While AP has demonstrated protective effects in various ischemia-reperfusion (I/R) injury models, its application in kidney injury remains largely unexplored.
Methods: An AP model was established in human kidney (HK2) cells by treating them with an acidic medium for 12 h, followed by a recovery period with a normal medium for 6 h. To induce hypoxia/reoxygenation (H/R) injury, HK2 cells were subjected to hypoxia for 24 h and reoxygenation for 1 h. In vivo, a mouse model of IPC was established by clamping the bilateral renal pedicles for 15 min, followed by reperfusion for 4 days. Conversely, the I/R model involved clamping the bilateral renal pedicles for 35 min and reperfusion for 24 h. Western blotting was employed to evaluate the expression levels of cleaved caspase 3, cleaved caspase 9, NHE1, KIM1, FAK, and NOX4. A pH-sensitive fluorescent probe was used to measure pHi, while a Hemin/CNF microelectrode monitored kidney tissue pH. Immunofluorescence staining was performed to visualize the localization of NHE1, NOX4, and FAK, along with the actin cytoskeleton structure in HK2 cells. Cell adhesion and scratch assays were conducted to assess cell motility.
Results: Our findings demonstrated that AP could effectively mitigate H/R injury in HK2 cells. This protective effect and the maintenance of pHi homeostasis by AP involved the upregulation of Na+/H+ exchanger 1 (NHE1) expression and activity. The activity of NHE1 was regulated by dynamic changes in pHi-dependent phosphorylation of Focal Adhesion Kinase (FAK) at Y397. This process was associated with NOX4-mediated reactive oxygen species (ROS) production. Furthermore, AP induced the co-localization of FAK, NOX4, and NHE1 in focal adhesions, promoting cytoskeletal remodeling and enhancing cell adhesion and migration capabilities.
Conclusions: This study provides compelling evidence that AP maintains pHi homeostasis and promotes cytoskeletal remodeling through FAK/NOX4/NHE1 signaling. This signaling pathway ultimately contributes to alleviated H/R injury in HK2 cells.
期刊介绍:
Cell Communication and Signaling (CCS) is a peer-reviewed, open-access scientific journal that focuses on cellular signaling pathways in both normal and pathological conditions. It publishes original research, reviews, and commentaries, welcoming studies that utilize molecular, morphological, biochemical, structural, and cell biology approaches. CCS also encourages interdisciplinary work and innovative models, including in silico, in vitro, and in vivo approaches, to facilitate investigations of cell signaling pathways, networks, and behavior.
Starting from January 2019, CCS is proud to announce its affiliation with the International Cell Death Society. The journal now encourages submissions covering all aspects of cell death, including apoptotic and non-apoptotic mechanisms, cell death in model systems, autophagy, clearance of dying cells, and the immunological and pathological consequences of dying cells in the tissue microenvironment.