1
|
Ren P, Lei W, Zhao C, Duan Z. HO-1-induced autophagy establishes a HO-1-p62-Nrf2 positive feedback loop to reduce gut permeability in cholestatic liver disease. Scand J Gastroenterol 2024; 59:906-917. [PMID: 38745449 DOI: 10.1080/00365521.2024.2353108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 04/22/2024] [Accepted: 05/05/2024] [Indexed: 05/16/2024]
Abstract
OBJECTIVES The gut-liver axis disruption is a unified pathogenetic principle of cholestatic liver disease (CSLD). Increased gut permeability is the leading cause of gut-liver axis disruption. HO-1 is capable of protecting against gut-liver axis injury. However, it has rarely been reported whether autophagy is involved in HO-1 protecting gut-liver barrier integrity and the underlying mechanism. MATERIALS AND METHODS Mice underwent bile duct ligation (BDL) was established as CSLD model in vivo. Caco-2 cells with LPS treatment was established as in vitro cell model. Immunofluorescence, western blot and transepithelial electrical resistance (TER) assay were used to observe epithelial tight junction (TJ) and autophagy. Liver injury and fibrosis were evaluated as well through H&E staining, masson staining, sirius red staining and ELISA. RESULTS AND CONCLUSIONS Our study demonstrated that the epithelial TJ and TER were notably reduced both in BDL mice and in LPS treated intestinal epithelial cells. Increased HO-1 expression could significantly induce intestinal epithelial cell autophagy. Additionally, this increased autophagy level reversed the reduction effects of BDL or LPS on epithelial TJ and TER in vivo and in vitro, therefore decreased transaminase level in serum and relieved liver fibrosis in BDL mice. Besides, increased autophagy level in turn upregulated the expression of HO-1 by p62 degradation of Keap1 and subsequent activation of Nrf2 pathway. Collectively, these results indicate that HO-1 reduces gut permeability by enhancing autophagy level in CSLD, the increased autophagy establishes a HO-1-p62-Nrf2 positive feedback loop to further improve gut-liver axis disruption. Therefore, our study confirms the critical role of autophagy in HO-1 ameliorating gut-liver axis injury during CSLD, highlighting HO-1 as a promising therapeutic target.
Collapse
Affiliation(s)
- Pingping Ren
- Second Department of Gastroenterology, The First Affiliated Hospital of Dalian Medical University, Dalian, China
- Second Department of Gastroenterology, The Second Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Wei Lei
- Second Department of Gastroenterology, The First Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Changcheng Zhao
- Second Department of Gastroenterology, The First Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Zhijun Duan
- Second Department of Gastroenterology, The First Affiliated Hospital of Dalian Medical University, Dalian, China
| |
Collapse
|
2
|
Liu X, Zhou Y, Zhang Y, Cui X, Yang D, Li Y. Octreotide attenuates intestinal barrier damage by maintaining basal autophagy in Caco2 cells. Mol Med Rep 2024; 29:90. [PMID: 38577927 PMCID: PMC11019401 DOI: 10.3892/mmr.2024.13214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 03/12/2024] [Indexed: 04/06/2024] Open
Abstract
The intestinal mucosal barrier is of great importance for maintaining the stability of the internal environment, which is closely related to the occurrence and development of intestinal inflammation. Octreotide (OCT) has potential applicable clinical value for treating intestinal injury according to previous studies, but the underlying molecular mechanisms have remained elusive. This article is based on a cell model of inflammation induced by lipopolysaccharide (LPS), aiming to explore the effects of OCT in protecting intestinal mucosal barrier function. A Cell Counting Kit‑8 assay was used to determine cell viability and evaluate the effectiveness of OCT. Gene silencing technology was used to reveal the mediated effect of somatostatin receptor 2 (SSTR2). The changes in intestinal permeability were detected through trans‑epithelial electrical resistance and fluorescein isothiocyanate‑dextran 4 experiments, and the alterations in tight junction proteins were detected using immunoblotting and reverse transcription fluorescence‑quantitative PCR technology. Autophagosomes were observed by electron microscopy and the dynamic changes of the autophagy process were characterized by light chain (LC)3‑II/LC3‑I conversion and autophagic flow. The results indicated that SSTR2‑dependent OCT can prevent the decrease in cell activity. After LPS treatment, the permeability of monolayer cells decreased and intercellular tight junctions were disrupted, resulting in a decrease in tight junction protein zona occludens 1 in cells. The level of autophagy‑related protein LC3 was altered to varying degrees at different times. These abnormal changes gradually returned to normal levels after the combined application of LPS and SSTR2‑dependent OCT, confirming the role of OCT in protecting intestinal barrier function. These experimental results suggest that OCT maintains basal autophagy and cell activity mediated by SSTR2 in intestinal epithelial cells, thereby preventing the intestinal barrier dysfunction in inflammation injury.
Collapse
Affiliation(s)
- Xiaoli Liu
- School of Basic Medical Sciences, Binzhou Medical University, Yantai, Shandong 264003, P.R. China
| | - Yan Zhou
- Department of Gastrointestinal Surgery, Yantai Mountain Hospital, Yantai, Shandong 264003, P.R. China
| | - Yu Zhang
- Department of Gastrointestinal Surgery, Yantai Affiliated Hospital of Binzhou Medical University, Yantai, Shandong 264003, P.R. China
| | - Xigang Cui
- Department of Gastrointestinal and Thyroid Surgery, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, Yantai, Shandong 264000, P.R. China
| | - Donglin Yang
- School of Basic Medical Sciences, Binzhou Medical University, Yantai, Shandong 264003, P.R. China
| | - Yuling Li
- School of Basic Medical Sciences, Binzhou Medical University, Yantai, Shandong 264003, P.R. China
| |
Collapse
|
3
|
Reches G, Piran R. Par2-mediated responses in inflammation and regeneration: choosing between repair and damage. Inflamm Regen 2024; 44:26. [PMID: 38816842 PMCID: PMC11138036 DOI: 10.1186/s41232-024-00338-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2024] [Accepted: 05/19/2024] [Indexed: 06/01/2024] Open
Abstract
The protease activated receptor 2 (Par2) plays a pivotal role in various damage models, influencing injury, proliferation, inflammation, and regeneration. Despite extensive studies, its binary roles- EITHER aggravating injury or promoting recovery-make a conclusive translational decision on its modulation strategy elusive. Analyzing two liver regeneration models, autoimmune hepatitis and direct hepatic damage, we discovered Par2's outcome depends on the injury's nature. In immune-mediated injury, Par2 exacerbates damage, while in direct tissue injury, it promotes regeneration. Subsequently, we evaluated the clinical significance of this finding by investigating Par2's expression in the context of autoimmune diabetes. We found that the absence of Par2 in all lymphocytes provided full protection against the autoimmune destruction of insulin-producing β-cells in mice, whereas the introduction of a β-cell-specific Par2 null mutation accelerated the onset of autoimmune diabetes. This pattern led us to hypothesize whether these observations are universal. A comprehensive review of recent Par2 publications across tissues and systems confirms the claim drafted above: Par2's initial activation in the immune system aggravates inflammation, hindering recovery, whereas its primary activation in the damaged tissue fosters regeneration. As a membrane-anchored receptor, Par2 emerges as an attractive drug target. Our findings highlight a crucial translational modulation strategy in regenerative medicine based on injury type.
Collapse
Affiliation(s)
- Gal Reches
- The Azrieli Faculty of Medicine, Bar-Ilan University, 8 Henrietta Szold St, Safed, Israel
| | - Ron Piran
- The Azrieli Faculty of Medicine, Bar-Ilan University, 8 Henrietta Szold St, Safed, Israel.
| |
Collapse
|
4
|
Chang YF, Li JJ, Liu T, Wei CQ, Ma LW, Nikolenko VN, Chang WL. Morphological and biochemical characteristics associated with autophagy in gastrointestinal diseases. World J Gastroenterol 2024; 30:1524-1532. [PMID: 38617452 PMCID: PMC11008416 DOI: 10.3748/wjg.v30.i11.1524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 01/05/2024] [Accepted: 02/20/2024] [Indexed: 03/21/2024] Open
Abstract
Autophagy is a cellular catabolic process characterized by the formation of double-membrane autophagosomes. Transmission electron microscopy is the most rigorous method to clearly visualize autophagic engulfment and degradation. A large number of studies have shown that autophagy is closely related to the digestion, secretion, and regeneration of gastrointestinal (GI) cells. However, the role of autophagy in GI diseases remains controversial. This article focuses on the morphological and biochemical characteristics of autophagy in GI diseases, in order to provide new ideas for their diagnosis and treatment.
Collapse
Affiliation(s)
- Yi-Fan Chang
- Department of Gastrointestinal Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan Province, China
| | - Jia-Jing Li
- Department of Pathology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan Province, China
| | - Tao Liu
- Department of Gastrointestinal Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan Province, China
| | - Chong-Qing Wei
- Department of Gastrointestinal Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan Province, China
| | - Li-Wei Ma
- Department of Clinical Laboratory, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan Province, China
| | - Vladimir N Nikolenko
- Department of Human Anatomy and Histology, I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow 119991, Russia
| | - Wei-Long Chang
- Department of Gastrointestinal Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan Province, China
| |
Collapse
|
5
|
Hou JJ, Ding L, Yang T, Yang YF, Jin YP, Zhang XP, Ma AH, Qin YH. The proteolytic activity in inflammatory bowel disease: insight from gut microbiota. Microb Pathog 2024; 188:106560. [PMID: 38272327 DOI: 10.1016/j.micpath.2024.106560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 01/20/2024] [Accepted: 01/22/2024] [Indexed: 01/27/2024]
Abstract
Inflammatory bowel disease (IBD) is a chronic, recurrent inflammatory disease caused by the destruction of the intestinal mucosal epithelium that affects a growing number of people worldwide. Although the etiology of IBD is complex and still elucidated, the role of dysbiosis and dysregulated proteolysis is well recognized. Various studies observed altered composition and diversity of gut microbiota, as well as increased proteolytic activity (PA) in serum, plasma, colonic mucosa, and fecal supernatant of IBD compared to healthy individuals. The imbalance of intestinal microecology and intestinal protein hydrolysis were gradually considered to be closely related to IBD. Notably, the pivotal role of intestinal microbiota in maintaining proteolytic balance received increasing attention. In summary, we have speculated a mesmerizing story, regarding the hidden role of PA and microbiota-derived PA hidden in IBD. Most importantly, we provided the diagnosis and therapeutic targets for IBD as well as the formulation of new treatment strategies for other digestive diseases and protease-related diseases.
Collapse
Affiliation(s)
- Jun-Jie Hou
- Department of Gastroenterology, Shaoxing People's Hospital, Shaoxing, PR China
| | - Liang Ding
- Department of Gastroenterology, Shaoxing People's Hospital, Shaoxing, PR China
| | - Tao Yang
- Department of Gastroenterology, Shaoxing People's Hospital, Shaoxing, PR China
| | - Yan-Fei Yang
- Department of Gastroenterology, Shaoxing People's Hospital, Shaoxing, PR China
| | - Yue-Ping Jin
- Department of Gastroenterology, Shaoxing People's Hospital, Shaoxing, PR China
| | - Xiao-Ping Zhang
- Department of Gastroenterology, Shaoxing People's Hospital, Shaoxing, PR China
| | - A-Huo Ma
- Department of Gastroenterology, Shaoxing People's Hospital, Shaoxing, PR China
| | - Yue-Hua Qin
- Department of Gastroenterology, Shaoxing People's Hospital, Shaoxing, PR China.
| |
Collapse
|
6
|
Veres-Székely A, Szász C, Pap D, Szebeni B, Bokrossy P, Vannay Á. Zonulin as a Potential Therapeutic Target in Microbiota-Gut-Brain Axis Disorders: Encouraging Results and Emerging Questions. Int J Mol Sci 2023; 24:ijms24087548. [PMID: 37108711 PMCID: PMC10139156 DOI: 10.3390/ijms24087548] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 04/05/2023] [Accepted: 04/18/2023] [Indexed: 04/29/2023] Open
Abstract
The relationship between dysbiosis and central nervous diseases has been proved in the last 10 years. Microbial alterations cause increased intestinal permeability, and the penetration of bacterial fragment and toxins induces local and systemic inflammatory processes, affecting distant organs, including the brain. Therefore, the integrity of the intestinal epithelial barrier plays a central role in the microbiota-gut-brain axis. In this review, we discuss recent findings on zonulin, an important tight junction regulator of intestinal epithelial cells, which is assumed to play a key role in maintaining of the blood-brain barrier function. In addition to focusing on the effect of microbiome on intestinal zonulin release, we also summarize potential pharmaceutical approaches to modulate zonulin-associated pathways with larazotide acetate and other zonulin receptor agonists or antagonists. The present review also addresses the emerging issues, including the use of misleading nomenclature or the unsolved questions about the exact protein sequence of zonulin.
Collapse
Affiliation(s)
- Apor Veres-Székely
- Pediatric Center, MTA Center of Excellence, Semmelweis University, 1083 Budapest, Hungary
- ELKH-SE Pediatrics and Nephrology Research Group, 1052 Budapest, Hungary
| | - Csenge Szász
- Pediatric Center, MTA Center of Excellence, Semmelweis University, 1083 Budapest, Hungary
| | - Domonkos Pap
- Pediatric Center, MTA Center of Excellence, Semmelweis University, 1083 Budapest, Hungary
- ELKH-SE Pediatrics and Nephrology Research Group, 1052 Budapest, Hungary
| | - Beáta Szebeni
- Pediatric Center, MTA Center of Excellence, Semmelweis University, 1083 Budapest, Hungary
- ELKH-SE Pediatrics and Nephrology Research Group, 1052 Budapest, Hungary
| | - Péter Bokrossy
- Pediatric Center, MTA Center of Excellence, Semmelweis University, 1083 Budapest, Hungary
| | - Ádám Vannay
- Pediatric Center, MTA Center of Excellence, Semmelweis University, 1083 Budapest, Hungary
- ELKH-SE Pediatrics and Nephrology Research Group, 1052 Budapest, Hungary
| |
Collapse
|
7
|
Jeong S, Kim Y, Park S, Lee D, Lee J, Hlaing SP, Yoo JW, Rhee SH, Im E. Lactobacillus plantarum Metabolites Elicit Anticancer Effects by Inhibiting Autophagy-Related Responses. Molecules 2023; 28:molecules28041890. [PMID: 36838877 PMCID: PMC9966080 DOI: 10.3390/molecules28041890] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 02/10/2023] [Accepted: 02/13/2023] [Indexed: 02/19/2023] Open
Abstract
Lactobacillus plantarum (L. plantarum) is a probiotic that has emerged as novel therapeutic agents for managing various diseases, such as cancer, atopic dermatitis, inflammatory bowel disease, and infections. In this study, we investigated the potential mechanisms underlying the anticancer effect of the metabolites of L. plantarum. We cultured L. plantarum cells to obtain their metabolites, created several dilutions, and used these solutions to treat human colonic Caco-2 cells. Our results showed a 10% dilution of L. plantarum metabolites decreased cell viability and reduced the expression of autophagy-related proteins. Moreover, we found co-treatment with L. plantarum metabolites and chloroquine, a known autophagy inhibitor, had a synergistic effect on cytotoxicity and downregulation of autophagy-related protein expression. In conclusion, we showed the metabolites from the probiotic, L. plantarum, work synergistically with chloroquine in killing Caco-2 cells and downregulating the expression of autophagy-related proteins, suggesting the involvement of autophagy, rather than apoptosis, in their cytotoxic effect. Hence, this study provides new insights into new therapeutic methods via inhibiting autophagy.
Collapse
Affiliation(s)
- Sihyun Jeong
- College of Pharmacy, Pusan National University, Busan 46241, Republic of Korea
| | - Yuju Kim
- College of Pharmacy, Pusan National University, Busan 46241, Republic of Korea
| | - Soyeong Park
- College of Pharmacy, Pusan National University, Busan 46241, Republic of Korea
| | - Doyeon Lee
- College of Pharmacy, Pusan National University, Busan 46241, Republic of Korea
| | - Juho Lee
- College of Pharmacy, Pusan National University, Busan 46241, Republic of Korea
| | - Shwe Phyu Hlaing
- College of Pharmacy, Pusan National University, Busan 46241, Republic of Korea
| | - Jin-Wook Yoo
- College of Pharmacy, Pusan National University, Busan 46241, Republic of Korea
- Research Institute for Drug Development, Pusan National University, Busan 46241, Republic of Korea
| | - Sang Hoon Rhee
- Department of Biological Sciences, Oakland University, Rochester, MI 48309, USA
| | - Eunok Im
- College of Pharmacy, Pusan National University, Busan 46241, Republic of Korea
- Research Institute for Drug Development, Pusan National University, Busan 46241, Republic of Korea
- Correspondence: ; Tel.:+82-51-510-2812; Fax:+82-50-513-6754
| |
Collapse
|
8
|
McArthur S. Regulation of Physiological Barrier Function by the Commensal Microbiota. Life (Basel) 2023; 13:life13020396. [PMID: 36836753 PMCID: PMC9964120 DOI: 10.3390/life13020396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Revised: 01/27/2023] [Accepted: 01/29/2023] [Indexed: 02/04/2023] Open
Abstract
A fundamental characteristic of living organisms is their ability to separate the internal and external environments, a function achieved in large part through the different physiological barrier systems and their component junctional molecules. Barrier integrity is subject to multiple influences, but one that has received comparatively little attention to date is the role of the commensal microbiota. These microbes, which represent approximately 50% of the cells in the human body, are increasingly recognized as powerful physiological modulators in other systems, but their role in regulating barrier function is only beginning to be addressed. Through comparison of the impact commensal microbes have on cell-cell junctions in three exemplar physiological barriers-the gut epithelium, the epidermis and the blood-brain barrier-this review will emphasize the important contribution microbes and microbe-derived mediators play in governing barrier function. By extension, this will highlight the critical homeostatic role of commensal microbes, as well as identifying the puzzles and opportunities arising from our steadily increasing knowledge of this aspect of physiology.
Collapse
Affiliation(s)
- Simon McArthur
- Institute of Dentistry, Faculty of Medicine & Dentistry, Queen Mary University of London, Blizard Institute, 4, Newark Street, London E1 2AT, UK
| |
Collapse
|
9
|
Parrón-Ballesteros J, Gordo RG, López-Rodríguez JC, Olmo N, Villalba M, Batanero E, Turnay J. Beyond allergic progression: From molecules to microbes as barrier modulators in the gut-lung axis functionality. FRONTIERS IN ALLERGY 2023; 4:1093800. [PMID: 36793545 PMCID: PMC9923236 DOI: 10.3389/falgy.2023.1093800] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 01/10/2023] [Indexed: 01/31/2023] Open
Abstract
The "epithelial barrier hypothesis" states that a barrier dysfunction can result in allergy development due to tolerance breakdown. This barrier alteration may come from the direct contact of epithelial and immune cells with the allergens, and indirectly, through deleterious effects caused by environmental changes triggered by industrialization, pollution, and changes in the lifestyle. Apart from their protective role, epithelial cells can respond to external factors secreting IL-25 IL-33, and TSLP, provoking the activation of ILC2 cells and a Th2-biased response. Several environmental agents that influence epithelial barrier function, such as allergenic proteases, food additives or certain xenobiotics are reviewed in this paper. In addition, dietary factors that influence the allergenic response in a positive or negative way will be also described here. Finally, we discuss how the gut microbiota, its composition, and microbe-derived metabolites, such as short-chain fatty acids, alter not only the gut but also the integrity of distant epithelial barriers, focusing this review on the gut-lung axis.
Collapse
Affiliation(s)
- Jorge Parrón-Ballesteros
- Department of Biochemistry and Molecular Biology, Faculty of Chemistry, Complutense University of Madrid, Madrid, Spain
| | - Rubén García Gordo
- Department of Biochemistry and Molecular Biology, Faculty of Chemistry, Complutense University of Madrid, Madrid, Spain
| | - Juan Carlos López-Rodríguez
- The Peter Gorer Department of Immunobiology, King's College London, London, United Kingdom,The Francis Crick Institute, London, United Kingdom
| | - Nieves Olmo
- Department of Biochemistry and Molecular Biology, Faculty of Chemistry, Complutense University of Madrid, Madrid, Spain
| | - Mayte Villalba
- Department of Biochemistry and Molecular Biology, Faculty of Chemistry, Complutense University of Madrid, Madrid, Spain
| | - Eva Batanero
- Department of Biochemistry and Molecular Biology, Faculty of Chemistry, Complutense University of Madrid, Madrid, Spain
| | - Javier Turnay
- Department of Biochemistry and Molecular Biology, Faculty of Chemistry, Complutense University of Madrid, Madrid, Spain,Correspondence: Javier Turnay
| |
Collapse
|
10
|
Yan JT, Zhu YZ, Liang L, Feng XY. NE-activated β 2-AR/β-arrestin 2/Src pathway mediates duodenal hyperpermeability induced by water-immersion restraint stress. Am J Physiol Cell Physiol 2023; 324:C133-C141. [PMID: 36440855 DOI: 10.1152/ajpcell.00412.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Stress causes a rapid spike in norepinephrine (NE) levels, leading to gastrointestinal dysfunction. NE reduces the expression of tight junctions (TJs) and aggravates intestinal mucosal damage, but the regulatory mechanism is still unclear. The present study aimed to investigate the molecular mechanisms underlying the regulation of stress-associated duodenal hyperpermeability by NE. Fluorescein isothiocyanate-dextran permeability, transepithelial resistance, immunofluorescence, Western blot, and high-performance liquid chromatography analysis were used in water-immersion restraint stress (WIRS) rats in this study. The results indicate that the duodenal permeability, degradation of TJs, mucosal NE, and β2-adrenergic receptor (β2-AR) increased in WIRS rats. The duodenal intracellular cyclic adenosine monophosphate levels were decreased, whereas the expression of β-arrestin 2 negatively regulates G protein-coupled receptors signaling, was significantly increased. Src recruitment was mediated by β-arrestin; thus, the levels of Src kinase activation were enhanced in WIRS rats. NE depletion, β2-AR, or β-arrestin 2 blockade significantly decreased mucosal permeability and increased TJs expression, suggesting improved mucosal barrier function. Moreover, NE induced an increased duodenal permeability of normal rats with activated β-arrestin 2/Src signaling, which was significantly inhibited by β2-AR blockade. The present findings demonstrate that the enhanced NE induced an increased duodenal permeability in WIRS rats through the activated β2-AR/β-arrestin 2/Src pathway. This study provides novel insight into the molecular mechanism underlying the regulation of NE on the duodenal mucosal barrier and a new target for treating duodenal ulcers induced by stress.
Collapse
Affiliation(s)
- Jing-Ting Yan
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China.,Department of Anesthesiology, The First Affiliated Hospital of Shandong First Medical University & Shandong Provincial Qianfoshan Hospital, Shandong Institute of Anesthesia and Respiratory Critical Medicine, Jinan, China
| | - Yin-Zhe Zhu
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Liang Liang
- Grade 2020 Pediatrics, School of Basic Medical Science, Capital Medical University, Beijing, China
| | - Xiao-Yan Feng
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| |
Collapse
|