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Whitmore M, Tobin I, Burkardt A, Zhang G. Nutritional Modulation of Host Defense Peptide Synthesis: A Novel Host-Directed Antimicrobial Therapeutic Strategy? Adv Nutr 2024; 15:100277. [PMID: 39053604 DOI: 10.1016/j.advnut.2024.100277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 06/11/2024] [Accepted: 07/19/2024] [Indexed: 07/27/2024] Open
Abstract
The escalating threat of antimicrobial resistance underscores the imperative for innovative therapeutic strategies. Host defense peptides (HDPs), integral components of innate immunity, exhibit profound antimicrobial and immunomodulatory properties. Various dietary compounds, such as short-chain fatty acids, vitamins, minerals, sugars, amino acids, phytochemicals, bile acids, probiotics, and prebiotics have been identified to enhance the synthesis of endogenous HDPs without provoking inflammatory response or compromising barrier integrity. Additionally, different classes of these compounds synergize in augmenting HDP synthesis and disease resistance. Moreover, dietary supplementation of several HDP-inducing compounds or their combinations have demonstrated robust protection in rodents, rabbits, pigs, cattle, and chickens from experimental infections. However, the efficacy of these compounds in inducing HDP synthesis varies considerably among distinct compounds. Additionally, the regulation of HDP genes occurs in a gene-specific, cell type-specific, and species-specific manner. In this comprehensive review, we systematically summarized the modulation of HDP synthesis and the mechanism of action attributed to each major class of dietary compounds, including their synergistic combinations, across a spectrum of animal species including humans. We argue that the ability to enhance innate immunity and barrier function without triggering inflammation or microbial resistance positions the nutritional modulation of endogenous HDP synthesis as a promising host-directed approach for mitigating infectious diseases and antimicrobial resistance. These HDP-inducing compounds, particularly in combinations, harbor substantial clinical potential for further exploration in antimicrobial therapies for both human and other animals.
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Affiliation(s)
- Melanie Whitmore
- Department of Animal and Food Sciences, Oklahoma State University, Stillwater, OK, United States
| | - Isabel Tobin
- Department of Animal and Food Sciences, Oklahoma State University, Stillwater, OK, United States
| | - Amanda Burkardt
- Department of Animal and Food Sciences, Oklahoma State University, Stillwater, OK, United States
| | - Guolong Zhang
- Department of Animal and Food Sciences, Oklahoma State University, Stillwater, OK, United States.
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Li S, Mu R, Guo X. Defensins regulate cell cycle: Insights of defensins on cellular proliferation and division. Life Sci 2024; 349:122740. [PMID: 38777302 DOI: 10.1016/j.lfs.2024.122740] [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: 02/20/2024] [Revised: 05/12/2024] [Accepted: 05/18/2024] [Indexed: 05/25/2024]
Abstract
Defensins are a class of small antimicrobial peptides that play a crucial role against pathogens. However, recent research has highlighted defensins exhibit the ability to influence cell cycle checkpoints, promoting or inhibiting specific phases such as G1 arrest or S/M transition. By regulating the cell cycle, defensins impact the proliferation of normal and cancerous cells, with implications for cancer development and progression. Dysregulation of defensin expression can disrupt the delicate balance of cell cycle regulation, leading to uncontrolled cell growth and an increased risk of tumor formation. Defensins contribute to the resolution of inflammation, stimulate angiogenesis, and enhance the migration and proliferation of cells involved in tissue repair. Furthermore, The ability of defensins to respond to microenvironmental changes further demonstrates the significance of these peptides in host defense mechanisms and immune function. By adjusting their expression, defensins continue to combat pathogens effectively and maintain homeostasis within the body. This review highlights the multifaceted role of defensins in regulating the cell cycle and their broader implications in cancer progression, tissue repair, and microenvironmental response.
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Affiliation(s)
- Shuang Li
- Institute of Wound Prevention and Treatment, Shanghai University of Medicine & Health Sciences, Shanghai, 201318, China.
| | - Rongrong Mu
- Affiliated Hospital of Sichuan Nursing Vocational College, The Third People's Hospital of Sichuan Province, China
| | - Xueqin Guo
- Department of Pathology, Gaomi City People's Hospital, Gaomi 261500, China
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Yan D, Wei G, Ai Z, Song S, Zhang L, Dong N, Dou X, Shan A. CXCR2, as a key regulatory gene of HDP-PG-1, maintains intestinal mucosal homeostasis. Int J Biol Macromol 2024; 269:132025. [PMID: 38704076 DOI: 10.1016/j.ijbiomac.2024.132025] [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: 03/05/2024] [Revised: 04/28/2024] [Accepted: 04/29/2024] [Indexed: 05/06/2024]
Abstract
The intestine defends against pathogenic microbial invasion via the secretion of host defense peptides (HDPs). Nutritional immunomodulation can stimulate the expression of endogenous HDPs and enhance the body's immune defense, representing a novel non-antibiotic strategy for disease prevention. The project aims to explore the regulatory mechanism of protegrin-1 (PG-1) expression using sodium phenylbutyrate (PBA) by omics sequencing technology and further investigate the role of key regulatory genes on intestinal health. The results showed that PBA promoted PG-1 expression in intestinal epithelial cells based on cell density through epidermal growth factor receptor (EGFR) and G protein-coupled receptor (GPR43). Transcriptome sequencing and microRNA sequencing revealed that C-X-C motif chemokine receptor 2 (CXCR2) exhibited interactions with PG-1. Pre-treatment cells with a CXCR2 inhibitor (SB225002) effectively suppressed the induction of PG-1 by PBA. Furthermore, SB225002 significantly suppressed the gene expression of HDPs in the jejunum of mice without influencing on the morphology, number of goblet cells, and proliferation of the intestine. CXCR2 inhibition significantly reduced the expression of HDPs during E. coli infection, and resulted in the edema of jejunal epithelial cells. The 16S rDNA analysis of cecal contents showed that the E. coli and SB225002 treatments changed gut microbiota diversity and composition at different taxonomic levels. Correlation analysis suggested a potential regulatory relationship between gut microbiota and HDPs. To that end, a gene involved in the HDP expression, CXCR2, has been identified in the study, which contributes to improving intestinal immune function. PBA may be used as a functional additive to regulate intestinal mucosal function, thereby enhancing the health of the intestinal and host.
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Affiliation(s)
- Di Yan
- College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China
| | - Guoyang Wei
- College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China
| | - Zichun Ai
- College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China
| | - Shuang Song
- College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China
| | - Licong Zhang
- College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China
| | - Na Dong
- College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China
| | - Xiujing Dou
- College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China.
| | - Anshan Shan
- College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China.
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Fu J, Zong X, Jin M, Min J, Wang F, Wang Y. Mechanisms and regulation of defensins in host defense. Signal Transduct Target Ther 2023; 8:300. [PMID: 37574471 PMCID: PMC10423725 DOI: 10.1038/s41392-023-01553-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 04/11/2023] [Accepted: 06/26/2023] [Indexed: 08/15/2023] Open
Abstract
As a family of cationic host defense peptides, defensins are mainly synthesized by Paneth cells, neutrophils, and epithelial cells, contributing to host defense. Their biological functions in innate immunity, as well as their structure and activity relationships, along with their mechanisms of action and therapeutic potential, have been of great interest in recent years. To highlight the key research into the role of defensins in human and animal health, we first describe their research history, structural features, evolution, and antimicrobial mechanisms. Next, we cover the role of defensins in immune homeostasis, chemotaxis, mucosal barrier function, gut microbiota regulation, intestinal development and regulation of cell death. Further, we discuss their clinical relevance and therapeutic potential in various diseases, including infectious disease, inflammatory bowel disease, diabetes and obesity, chronic inflammatory lung disease, periodontitis and cancer. Finally, we summarize the current knowledge regarding the nutrient-dependent regulation of defensins, including fatty acids, amino acids, microelements, plant extracts, and probiotics, while considering the clinical application of such regulation. Together, the review summarizes the various biological functions, mechanism of actions and potential clinical significance of defensins, along with the challenges in developing defensins-based therapy, thus providing crucial insights into their biology and potential clinical utility.
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Affiliation(s)
- Jie Fu
- Key Laboratory of Molecular Animal Nutrition, Ministry of Education, College of Animal Sciences, Zhejiang University, Hangzhou, China
- Key Laboratory of Animal Nutrition and Feed Science in Eastern China, Ministry of Agriculture, Hangzhou, Zhejiang Province, China
| | - Xin Zong
- Key Laboratory of Molecular Animal Nutrition, Ministry of Education, College of Animal Sciences, Zhejiang University, Hangzhou, China
- Key Laboratory of Animal Nutrition and Feed Science in Eastern China, Ministry of Agriculture, Hangzhou, Zhejiang Province, China
| | - Mingliang Jin
- Key Laboratory of Molecular Animal Nutrition, Ministry of Education, College of Animal Sciences, Zhejiang University, Hangzhou, China
- Key Laboratory of Animal Nutrition and Feed Science in Eastern China, Ministry of Agriculture, Hangzhou, Zhejiang Province, China
| | - Junxia Min
- The First Affiliated Hospital, Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, 310058, China
| | - Fudi Wang
- The Second Affiliated Hospital, School of Public Health, State Key Laboratory of Experimental Hematology, Zhejiang University School of Medicine, Hangzhou, China.
- The First Affiliated Hospital, Basic Medical Sciences, School of Public Health, Hengyang Medical School, University of South China, Hengyang, China.
| | - Yizhen Wang
- Key Laboratory of Molecular Animal Nutrition, Ministry of Education, College of Animal Sciences, Zhejiang University, Hangzhou, China.
- Key Laboratory of Animal Nutrition and Feed Science in Eastern China, Ministry of Agriculture, Hangzhou, Zhejiang Province, China.
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Dou X, Yan D, Liu S, Gao N, Ma Z, Shi Z, Dong N, Shan A. Host Defense Peptides in Nutrition and Diseases: A Contributor of Immunology Modulation. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:3125-3140. [PMID: 36753427 DOI: 10.1021/acs.jafc.2c08522] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Host defense peptides (HDPs) are primary components of the innate immune system with diverse biological functions, such as antibacterial ability and immunomodulatory function. HDPs are produced and released by immune and epithelial cells against microbial invasion, which are widely distributed in humans, animals, plants, and microbes. Notably, there are great differences in endogenous HDP distribution and expression in humans and animals. Moreover, HDP expression could be regulated by exogenous substances, such as nutrients, and different physiological statuses in health and disease. In this review, we systematically assessed the regulation of expression and mechanism of endogenous HDPs from nutrition and disease perspectives, providing a basis to identify the specificity and regularity of HDP expression. Furthermore, the regulation mechanism of HDP expression was summarized systematically, and the differences in the regulation between nutrients and diseases were explored. From this review, we provide novel ideas targeted the immune regulation of HDPs for protecting host health in nutrition and practical and effective new ideas using the immune regulation theory for further research on protecting host health from pathogenic infection and excessive immunity diseases under the global challenge of the antibiotic-abuse-induced series of problems, including food security and microbial resistance.
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Affiliation(s)
- Xiujing Dou
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, Heilongjiang 150030, People's Republic of China
| | - Di Yan
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, Heilongjiang 150030, People's Republic of China
| | - Siqi Liu
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, Heilongjiang 150030, People's Republic of China
| | - Nan Gao
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, Heilongjiang 150030, People's Republic of China
| | - Ziwen Ma
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, Heilongjiang 150030, People's Republic of China
| | - Zixuan Shi
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, Heilongjiang 150030, People's Republic of China
| | - Na Dong
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, Heilongjiang 150030, People's Republic of China
| | - Anshan Shan
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, Heilongjiang 150030, People's Republic of China
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Ge L, Zou S, Yuan Z, Chen W, Wang S, Cao X, Lv X, Getachew T, Mwacharo JM, Haile A, Sun W. Sheep β-Defensin 2 Regulates Escherichia coli F17 Resistance via NF-κB and MAPK Signaling Pathways in Ovine Intestinal Epithelial Cells. BIOLOGY 2021; 10:biology10121356. [PMID: 34943272 PMCID: PMC8698448 DOI: 10.3390/biology10121356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 12/16/2021] [Accepted: 12/17/2021] [Indexed: 11/16/2022]
Abstract
Simple Summary This study was conducted to explore the antibacterial ability of sheep β-defensin 2 (SBD-2) against E. coli F17 infection in ovine intestinal epithelial cells (OIECs). Our data revealed that E. coli F17 induces SBD-2 expression in OIECs in vitro, which appears to be mediated through the activation of the signaling pathways NF-κB and MAPK. Our results provide a novel insight for the functionality of SBD-2, which could be useful for developing anti-infective drugs and/or breeding for E. coli diarrhea disease-resistant sheep. Abstract Escherichia coli (E. coli) F17 is a member of enterotoxigenic Escherichia coli, which can cause massive diarrhea and high mortality in newborn lambs. β-defensin is mainly produced by the epithelial tissue of the gastrointestinal tract in response to microbial infection. However, the molecular mechanism of sheep β-defensin 2 (SBD-2) against E. coli F17 remains unclear. This study aims to reveal the antibacterial ability of SBD-2 against E. coli F17 infection in sheep. Firstly, we established the culture system of ovine intestinal epithelial cells (OIECs) in vitro, treated with different concentrations of E. coli F17 for an indicated time. Secondly, we performed RNA interference and overexpression to investigate the effect of SBD-2 expression on E. coli F17 adhesion to OIECs. Finally, inhibitors of NF-κB and MAPK pathways were pre-treated to explore the possible relationship involving in E. coli F17 infection regulating SBD-2 expression. The results showed that E. coli F17 markedly (p < 0.01) upregulated the expression levels of SBD-2 mRNA and protein in a concentration- and time-dependent manner. Overexpression of SBD-2 contributed to enhancing E. coli F17 resistance in OIECs, while silencing SBD-2 dramatically improved the adhesion of E. coli F17 to OIECs (p < 0.05 or p < 0.01). Furthermore, E. coli F17 stimulated SBD-2 expression was obviously decreased by pre-treatment with NF-κB inhibitor PDTC, p38 MAPK inhibitor SB202190 and ERK1/2 MAPK inhibitor PD98095 (p < 0.05 or p < 0.01). Interestingly, adhesion of E. coli F17 to OIECs were highly enhanced by pre-treated with PDTC, SB202190 and PD98095. Our data suggested that SBD-2 could inhibit E. coli F17 infection in OIECs, possibly through NF-κB and MAPK signaling pathways. Our results provide useful theoretical basis on developing anti-infective drug and breeding for E. coli diarrhea disease-resistant sheep.
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Affiliation(s)
- Ling Ge
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225000, China; (L.G.); (S.Z.); (W.C.); (S.W.)
| | - Shuangxia Zou
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225000, China; (L.G.); (S.Z.); (W.C.); (S.W.)
| | - Zehu Yuan
- Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education, Yangzhou University, Yangzhou 225000, China; (Z.Y.); (X.C.); (X.L.)
| | - Weihao Chen
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225000, China; (L.G.); (S.Z.); (W.C.); (S.W.)
| | - Shanhe Wang
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225000, China; (L.G.); (S.Z.); (W.C.); (S.W.)
| | - Xiukai Cao
- Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education, Yangzhou University, Yangzhou 225000, China; (Z.Y.); (X.C.); (X.L.)
| | - Xiaoyang Lv
- Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education, Yangzhou University, Yangzhou 225000, China; (Z.Y.); (X.C.); (X.L.)
| | - Tesfaye Getachew
- International Centre for Agricultural Research in the Dry Areas, Addis Ababa 999047, Ethiopia; (T.G.); (J.M.M.); (A.H.)
| | - Joram M. Mwacharo
- International Centre for Agricultural Research in the Dry Areas, Addis Ababa 999047, Ethiopia; (T.G.); (J.M.M.); (A.H.)
| | - Aynalem Haile
- International Centre for Agricultural Research in the Dry Areas, Addis Ababa 999047, Ethiopia; (T.G.); (J.M.M.); (A.H.)
| | - Wei Sun
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225000, China; (L.G.); (S.Z.); (W.C.); (S.W.)
- Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education, Yangzhou University, Yangzhou 225000, China; (Z.Y.); (X.C.); (X.L.)
- Correspondence:
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Gerbeth L, Glauben R. Histone Deacetylases in the Inflamed Intestinal Epithelium-Promises of New Therapeutic Strategies. Front Med (Lausanne) 2021; 8:655956. [PMID: 33842512 PMCID: PMC8032862 DOI: 10.3389/fmed.2021.655956] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 03/05/2021] [Indexed: 12/22/2022] Open
Abstract
The intestinal epithelium is a complex, dynamic barrier that separates luminal contents from the immune compartment while mediating nutrient absorption and controlled passage of antigens to convey oral tolerance. A compromised epithelial barrier often leads to inflammation because immune cells in the lamina propria come into direct contact with luminal antigens. Defects in epithelial cell function were also shown to be involved in the etiology of inflammatory bowel diseases. These are severe, chronically relapsing inflammatory conditions of the gastrointestinal tract that also increase the risk of developing colorectal cancer. Despite major efforts of the scientific community, the precise causes and drivers of these conditions still remain largely obscured impeding the development of a permanent cure. Current therapeutic approaches mostly focus on alleviating symptoms by targeting immune cell signaling. The protein family of histone deacetylases (HDACs) has gained increasing attention over the last years, as HDAC inhibitors were shown to be potent tumor cell suppressors and also alleviate morbid inflammatory responses. Recent research continuously identifies new roles for specific HDACs suggesting that HDACs influence the cell signaling network from many different angles. This makes HDACs very interesting targets for therapeutic approaches but predicting effects after system manipulations can be difficult. In this review, we want to provide a comprehensive overview of current knowledge about the individual roles of HDACs in the intestinal epithelium to evaluate their therapeutic potential for inflammatory conditions of the gut.
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Affiliation(s)
- Lorenz Gerbeth
- Department of Gastroenterology, Infectious Diseases and Rheumatology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany.,Department of Medical Biotechnology, Institute of Biotechnology, Technische Universität Berlin, Berlin, Germany
| | - Rainer Glauben
- Department of Gastroenterology, Infectious Diseases and Rheumatology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
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Dou X, Gao N, Lan J, Han J, Yang Y, Shan A. TLR2/EGFR Are Two Sensors for pBD3 and pEP2C Induction by Sodium Butyrate Independent of HDAC Inhibition. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:512-522. [PMID: 31870150 DOI: 10.1021/acs.jafc.9b06569] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Host defense peptides (HDPs) are vital mucosal defense effectors of the innate immune response. The expression of HDPs is inducible in epithelial cells by potent endogenous inducers. Herein, our results demonstrate that sodium butyrate (NaB) induces the expression of porcine β-defensin-3 (pBD3) and porcine epididymis protein 2 splicing variant C (pEP2C) in a dose- and time-dependent manner, without modifying the production of proinflammatory cytokines, in porcine intestinal epithelial cells (IPEC J2). Moreover, NaB promotes toll-like receptor 2 (TLR2) expression. TLR2 silencing inhibits the pBD3 and pEP2C expression induced by NaB but does not abolish the histone deacetylase (HDAC) inhibitory activity of NaB. We found that NaB activated the nuclear factor-κB (NF-κB) pathway. Importantly, the degree of cell confluence governs the regulatory responses but does not affect the HDAC activity of NaB. Furthermore, epidermal growth factor receptor (EGFR), but not the mitogen-activated protein kinase (MAPK) pathway, is vital during the NaB-induced pBD3 and pEP2C regulation process. We also demonstrated that pBD3 overexpression increases interleukin-18 levels. This study showed that NaB simultaneously induces pBD3 and pEP2C via TLR2 and EGFR in IPEC J2 cells without increasing the risk of a harmful inflammatory response.
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Affiliation(s)
- Xiujing Dou
- Institute of Animal Nutrition , Northeast Agricultural University , Harbin 150030 , P.R. China
| | - Nan Gao
- Institute of Animal Nutrition , Northeast Agricultural University , Harbin 150030 , P.R. China
| | - Jing Lan
- Institute of Animal Nutrition , Northeast Agricultural University , Harbin 150030 , P.R. China
| | - Junlan Han
- Institute of Animal Nutrition , Northeast Agricultural University , Harbin 150030 , P.R. China
| | - Yang Yang
- Institute of Animal Nutrition , Northeast Agricultural University , Harbin 150030 , P.R. China
| | - Anshan Shan
- Institute of Animal Nutrition , Northeast Agricultural University , Harbin 150030 , P.R. China
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