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Alhendi A, Naser SA. In vitro neutralization of IL-6 receptor exacerbates damage to intestinal epithelial cells during Mycobacterium avium paratuberculosis infection. Front Immunol 2024; 15:1412800. [PMID: 39170608 PMCID: PMC11335550 DOI: 10.3389/fimmu.2024.1412800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Accepted: 07/23/2024] [Indexed: 08/23/2024] Open
Abstract
Like TNFα, IL-6 is upregulated in Crohn's disease (CD) especially in patients associated with Mycobacterium avium paratuberculosis (MAP) infection, and both cytokines have been targeted as a therapeutic option for the treatment of the disease despite the accepted partial response in some patients. Limited response to anti-IL-6 receptor-neutralizing antibodies therapy may be related to the homeostatic dual role of IL-6. In this study, we investigated the effects and the signaling mechanism of IL-6 involved in intestinal epithelial integrity and function during MAP infection using an in vitro model that consists of THP-1, HT-29 and Caco-2 cell lines. Clinically, we determined that plasma samples from MAP-infected CD patients have higher IL-6 levels compared to controls (P-value < 0.001). In CD-like macrophages, MAP infection has significantly upregulated the secretion of IL-6 and the shedding of (IL-6R) from THP-1 macrophages, P-value < 0.05. Intestinal cell lines (Caco-2 and HT-29) were treated with the supernatant of MAP-infected THP-1 macrophages with or without a neutralizing anti-IL-6R antibody. Treating intestinal Caco-2 cells with supernatant of MAP-infected macrophages resulted in significant upregulation of intestinal damage markers including claudin-2 and SERPINE1/PAI-1. Interestingly, blocking IL-6 signaling exacerbated that damage and further increased the levels of the damage markers. In HT-29 cells, MAP infection upregulated MUC2 expression, a protective response that was reversed when IL-6R was neutralized. More importantly, blocking IL-6 signaling during MAP infection rescued damaged Caco-2 cells from MAP-induced apoptosis. The data clearly supports a protective role of IL-6 in intestinal epithelia integrity and function especially in CD patients associated with MAP infection. The findings may explain the ineffective response to anti-IL6 based therapy and strongly support a therapeutic option that restores the physiologic level of IL-6 in patient's plasma. A new treatment strategy based on attenuation of IL-6 expression and secretion in inflammatory diseases should be considered.
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Affiliation(s)
| | - Saleh A. Naser
- Division of Molecular Microbiology, Burnett School of Biomedical Sciences, College of Medicine. University of Central Florida, Orlando, FL, United States
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2
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Lv J, Fu Y, Ga Y, Han C, Fan Y, Wei Y, Hao S, Hao Z. Lianweng Granules Alleviate Intestinal Barrier Damage via the IL-6/STAT3/PI3K/AKT Signaling Pathway with Dampness-Heat Syndrome Diarrhea. Antioxidants (Basel) 2024; 13:661. [PMID: 38929100 PMCID: PMC11201218 DOI: 10.3390/antiox13060661] [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: 05/10/2024] [Revised: 05/24/2024] [Accepted: 05/25/2024] [Indexed: 06/28/2024] Open
Abstract
Dampness-heat syndrome diarrhea (DHSD) is a common clinical disease with a high prevalence but still has no satisfactory therapeutic medicine, so the search for a safe and effective drug candidate is ongoing. This study aims to explore the efficacy and mechanisms of Lianweng granules (LWG) in the treatment of DHSD and to identify the blood transport components of LWG. We assessed the efficacy of LWG in DHSD by various in vivo metrics such as body weight, disease activity index (DAI), histopathologic examination, intestinal barrier function, levels of inflammatory, apoptotic biomarkers, and oxidative stress. We identified the blood components of LWG using ultra-high performance liquid chromatography-mass spectrometry/mass spectrometry (UHPLC-MS/MS), and the resolved key components were used to explore the relevant targets. We next predicted the potential mechanisms of LWG in treating DHSD using network pharmacology and molecular docking based on the relevant targets. Finally, the mechanisms were validated in vivo using RT-qPCR, Western blotting, ELISA, and immunofluorescence and evaluated in vitro using Cell Counting Kit-8 (CCK-8), small interfering RNA, cellular enthusiasm transfer assay (CETSA), and drug affinity response target stability (DARTS). Ninety-one pharmacodynamic components of LWG enter the bloodstream and exert possible therapeutic effects. In vivo, LWG treatment improved body weight, reduced colonic injury and DAI scores, lowered inflammation, oxidative stress, and apoptosis markers, and partially restored intestinal barrier function in DHSD mice. Guided by network pharmacology and molecular docking, it is suggested that LWG may exert therapeutic effects by inhibiting IL-6/STAT3/PI3K/AKT signaling. LWG significantly decreased the expression of IL-6, p-STAT3, p-PI3K, p-AKT, and other proteins. These findings were supported by in vitro experiments, where CETSA, DARTS, and siRNA evidenced LWG's targeting of STAT3. LWG targeted STAT3 to inhibit inflammation, oxidative stress, and apoptosis in the colon, thereby restoring the intestinal barrier function to some extent and exerting a therapeutic effect on DHSD.
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Affiliation(s)
- Jianyu Lv
- Innovation Centre of Chinese Veterinary Medicine, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China; (J.L.); (Y.F.); (Y.G.); (C.H.); (Y.F.); (Y.W.)
- Key Biology Laboratory of Chinese Veterinary Medicine, Ministry of Agriculture and Rural Affairs, Beijing 100193, China
- National Center of Technology Innovation for Medicinal Function of Food, National Food and Strategic Reserves Administration, Beijing 100193, China
| | - Yuchen Fu
- Innovation Centre of Chinese Veterinary Medicine, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China; (J.L.); (Y.F.); (Y.G.); (C.H.); (Y.F.); (Y.W.)
- Key Biology Laboratory of Chinese Veterinary Medicine, Ministry of Agriculture and Rural Affairs, Beijing 100193, China
- National Center of Technology Innovation for Medicinal Function of Food, National Food and Strategic Reserves Administration, Beijing 100193, China
| | - Yu Ga
- Innovation Centre of Chinese Veterinary Medicine, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China; (J.L.); (Y.F.); (Y.G.); (C.H.); (Y.F.); (Y.W.)
- Key Biology Laboratory of Chinese Veterinary Medicine, Ministry of Agriculture and Rural Affairs, Beijing 100193, China
- National Center of Technology Innovation for Medicinal Function of Food, National Food and Strategic Reserves Administration, Beijing 100193, China
| | - Chao Han
- Innovation Centre of Chinese Veterinary Medicine, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China; (J.L.); (Y.F.); (Y.G.); (C.H.); (Y.F.); (Y.W.)
- Key Biology Laboratory of Chinese Veterinary Medicine, Ministry of Agriculture and Rural Affairs, Beijing 100193, China
- National Center of Technology Innovation for Medicinal Function of Food, National Food and Strategic Reserves Administration, Beijing 100193, China
| | - Yimeng Fan
- Innovation Centre of Chinese Veterinary Medicine, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China; (J.L.); (Y.F.); (Y.G.); (C.H.); (Y.F.); (Y.W.)
- Key Biology Laboratory of Chinese Veterinary Medicine, Ministry of Agriculture and Rural Affairs, Beijing 100193, China
- National Center of Technology Innovation for Medicinal Function of Food, National Food and Strategic Reserves Administration, Beijing 100193, China
| | - Yuanyuan Wei
- Innovation Centre of Chinese Veterinary Medicine, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China; (J.L.); (Y.F.); (Y.G.); (C.H.); (Y.F.); (Y.W.)
- Key Biology Laboratory of Chinese Veterinary Medicine, Ministry of Agriculture and Rural Affairs, Beijing 100193, China
- National Center of Technology Innovation for Medicinal Function of Food, National Food and Strategic Reserves Administration, Beijing 100193, China
| | - Sijia Hao
- College of Traditional Chinese Medicine, Inner Mongolia Medical University, Hohhot 010059, China;
| | - Zhihui Hao
- Innovation Centre of Chinese Veterinary Medicine, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China; (J.L.); (Y.F.); (Y.G.); (C.H.); (Y.F.); (Y.W.)
- Key Biology Laboratory of Chinese Veterinary Medicine, Ministry of Agriculture and Rural Affairs, Beijing 100193, China
- National Center of Technology Innovation for Medicinal Function of Food, National Food and Strategic Reserves Administration, Beijing 100193, China
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3
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Wang X, Huang S, Zhang M, Su Y, Pan Z, Liang J, Xie X, Wang Q, Chen J, Zhou L, Luo X. Gegen Qinlian decoction activates AhR/IL-22 to repair intestinal barrier by modulating gut microbiota-related tryptophan metabolism in ulcerative colitis mice. JOURNAL OF ETHNOPHARMACOLOGY 2023; 302:115919. [PMID: 36356716 DOI: 10.1016/j.jep.2022.115919] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 11/03/2022] [Accepted: 11/05/2022] [Indexed: 06/16/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Gegen Qinlian decoction (GQD) is a traditional Chinese medicine derived from Treatise on febrile diseases and is clinically used for the treatment of acute ulcerative colitis (UC). However, the potential mechanism of GQD treatment for UC remains elusive. AIM OF STUDY In this study, we aimed to explore the involvement of gut microbiota-related tryptophan metabolism in mediating protective effects of GQD against intestinal barrier damage. MATERIALS AND METHODS Mice with colitis were treated with 3% dextran sulfate sodium (DSS) for 6 days. The therapeutic effects of GQD in UC mice were examined based on body weight, disease activity index (DAI), organ index, length and pathological changes in the colon. The distribution of fluorescein isothiocyanate dextran (FITC-dextran) in the intestinal tract was observed using small animal imaging, while concentration of FITC-dextran in serum was detected using a fluorescein microplate analyser. Bacterial infiltration in colon tissues was observed by fluorescence in situ hybridisation (FISH), and the bacterial load in mesenteric lymph nodes (MLNs) was further examined through bacterial culture. Subsequently, colonic goblet cells were detected using Alcian blue staining. The tight junctions of the colonic epithelium were observed using transmission electron microscopy, and the expression of tight junction proteins was detected by immunofluorescence (IF) and western blot. In addition, flow cytometry was used to analyse the proportion of interleukin-22-positive (IL-22+) ILC3 cells in lamina propria lymphocytes, and the content of IL-22 in colon homogenates was determined using an ELISA kit. In addition, targeted tryptophan metabolomics was used to detect the concentration of indole derivatives produced by tryptophan metabolism in faeces, and 16S rDNA was used to investigate the composition and abundance of gut microbiota-related tryptophan metabolism. RESULTS Administration of GQD significantly alleviated the pathological symptoms, including weight loss, increased DAI score, changes in organ index, colon shortening, and colon pathological injury in UC mice. In addition, GQD reduced the diffusion of FITC-dextran in the intestinal tract, the content of FITC-dextran in serum, and bacterial infiltration in MLNs and colon tissues. Additionally, GQD significantly increased the number of colonic goblet cells, repaired the structure of epithelial tight junctions and increased the expression of tight junction proteins. Furthermore, GQD significantly increased the proportion of IL-22+ ILC3 in the lamina propria, the expression of CYP1A1 protein in colon tissue, and the level of IL-22 in colon homogenates. However, the above protective effects of GQD were inhibited by co-administration of GQD and aryl hydrocarbon receptor (AhR) antagonist. Additionally, GQD restored the content of indole derivatives generated by tryptophan metabolism, regulated the diversity of the gut microbiota, and significantly increased the abundance of genes related to tryptophan metabolism. CONCLUSION Our results confirmed that GQD repaired the damaged intestinal barrier in UC mice by regulating gut microbiota-related tryptophan metabolism and restoring the generation of indole derivatives to activate AhR-mediated IL-22 production.
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Affiliation(s)
- Xiaojing Wang
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, China; The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Shaowei Huang
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Meiling Zhang
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yulin Su
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Zengfeng Pan
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Junjie Liang
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Xueqian Xie
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Qing Wang
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Jinyan Chen
- Basic Medical College, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Lian Zhou
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, China.
| | - Xia Luo
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, China.
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Sarma R, Shakya A, Karmakar A, Ghosh SK, Bhat HR, Ghimire N, Rahman O. A Review Of Preclinical Tools To Validate Anti-Diarrheal Agents. Curr Rev Clin Exp Pharmacol 2022; 19:CRCEP-EPUB-127705. [PMID: 36411576 DOI: 10.2174/2772432818666221121113622] [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: 04/23/2022] [Revised: 07/04/2022] [Accepted: 08/26/2022] [Indexed: 11/23/2022]
Abstract
BACKGROUND Since their inception, preclinical experimental models have played an important role in investigating and characterizing disease pathogenesis. These in vivo, ex vivo, and in vitro preclinical tests also aid in identifying targets, evaluating potential therapeutic drugs, and validating treatment protocols. INTRODUCTION Diarrhea is a leading cause of mortality and morbidity, particularly among children in developing countries, and it represents a huge health-care challenge on a global scale. Due to its chronic manifestations, alternative anti-diarrheal medications must be tested and developed because of the undesirable side effects of currently existing anti-diarrheal drugs. METHODS Several online databases, including Science Direct, PubMed, Web of Science, Google Scholar and Scopus, were used in the literature search. The datasets were searched for entries of studies up to May, 2022. RESULTS The exhaustive literature study provides a large number of in vivo, in vitro and ex vivo models, which have been used for evaluating the mechanism of the anti-diarrheal effect of drugs in chemically-, pathogen-, disease-induced animal models of diarrhea. The advances and challenges of each model were also addressed in this review. CONCLUSION This review encompasses diverse strategies for screening drugs with anti-diarrheal effects and covers a wide range of pathophysiological and molecular mechanisms linked to diarrhea, with a particular emphasis on the challenges of evaluating and predictively validating these experimental models in preclinical studies. This could also help researchers find a new medicine to treat diabetes more effectively and with fewer adverse effects.
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Affiliation(s)
- Rajdeep Sarma
- Department of Pharmaceutical Sciences, School of Science and Engineering, Dibrugarh University, Dibrugarh - 786004, Assam, India
| | - Anshul Shakya
- Department of Pharmaceutical Sciences, School of Science and Engineering, Dibrugarh University, Dibrugarh - 786004, Assam, India
| | - Arka Karmakar
- Department of Pharmaceutical Sciences, School of Science and Engineering, Dibrugarh University, Dibrugarh - 786004, Assam, India
| | - Surajit Kumar Ghosh
- Department of Pharmaceutical Sciences, School of Science and Engineering, Dibrugarh University, Dibrugarh - 786004, Assam, India
| | - Hans Raj Bhat
- Department of Pharmaceutical Sciences, School of Science and Engineering, Dibrugarh University, Dibrugarh - 786004, Assam, India
| | - Neha Ghimire
- Department of Pharmaceutical Sciences, School of Science and Engineering, Dibrugarh University, Dibrugarh - 786004, Assam, India
| | - Obaidur Rahman
- Department of Pharmaceutical Sciences, School of Science and Engineering, Dibrugarh University, Dibrugarh - 786004, Assam, India
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Wu J, Niu J, Li M, Miao Y. Keratin 1 maintains the intestinal barrier in ulcerative colitis. Genes Genomics 2021; 43:1389-1402. [PMID: 34562265 DOI: 10.1007/s13258-021-01166-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Accepted: 09/14/2021] [Indexed: 12/20/2022]
Abstract
BACKGROUND The intestinal mechanical barrier plays a key role in the pathogenesis of ulcerative colitis (UC). Our previous study showed keratin 1 (KRT1) was downregulated in UC, but the mechanism by which KRT1 affects the intestinal barrier remains unknown. OBJECTIVES To explore the mechanism of KRT1 in the intestinal barrier in UC. METHODS Colonic tissues were collected from 20 UC patients before and after mucosal healing (MH) and 15 healthy controls. The expression of KRT1 was measured by PCR, western blotting and immunohistochemistry (IHC). A dextran sulfate sodium (DSS)-induced colitis model was established in krt1 transgenic (TG) mice, and the mice were treated with methylprednisolone (MP) to explore the role of KRT1 in the intestinal barrier. Inflammation was evaluated through the DAI score, colon, spleen and H&E. The expression of KRT1 and tight junction (TJ) proteins in mouse was analysed by the same methods. RESULTS The transcription and expression of KRT1 in UC was decreased and recovered after MH but did not reach the level of the healthy controls. Similar to the clinical results, the expression of krt1 was decreased in DSS-induced colitis and upregulated after MP. Moreover, the krt1 TG group exhibited less inflammation than wild-type (WT) group. The expression of Occludin and ZO-1 decreased after DSS induction, the decreases in Occludin and ZO-1 in the krt1 TG group were lower than WT group, which was significantly increased after MP, while the expression of Claudin-2 exhibited the opposite effect. CONCLUSIONS Keratin 1 maintains the intestinal barrier by upregulating TJ proteins in UC.
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Affiliation(s)
- Jing Wu
- Department of Gastroenterology, The First Affiliated Hospital of Kunming Medical University, No. 295 Xichang Road, Kunming, 650032, Yunnan, China
| | - Junkun Niu
- Department of Gastroenterology, The First Affiliated Hospital of Kunming Medical University, No. 295 Xichang Road, Kunming, 650032, Yunnan, China
| | - Maojuan Li
- Department of Gastroenterology, The First Affiliated Hospital of Kunming Medical University, No. 295 Xichang Road, Kunming, 650032, Yunnan, China
| | - Yinglei Miao
- Department of Gastroenterology, The First Affiliated Hospital of Kunming Medical University, No. 295 Xichang Road, Kunming, 650032, Yunnan, China.
- Yunnan Province Clinical Research Center for Digestive Diseases, Kunming, Yunnan, China.
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6
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Rodríguez Basso A, Carranza A, Zainutti VM, Bach H, Gorzalczany SB. Pharmacologycal activity of peperina (Minthostachys verticillata) on gastrointestinal tract. JOURNAL OF ETHNOPHARMACOLOGY 2021; 269:113712. [PMID: 33352243 DOI: 10.1016/j.jep.2020.113712] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 12/15/2020] [Accepted: 12/16/2020] [Indexed: 06/12/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Minthostachys verticillata (Griseb.) Epling (Lamiaceae), known as Peperina is a medicinal native plant, with a traditional use as a digestive, antispasmodic and antidiarrheic. AIM OF THE STUDY Despite its folkloric use, no scientific evaluation of this plant related to the gastrointestinal inflammatory process has been carried out to date. The present study aims to assess the effects of M. verticillata on gastrointestinal system in experimental models. MATERIALS AND METHODS M. verticillata (250 and 500 mg/kg) was orally tested in a colitis model induced by acetic acid. Colon weight/length ratio, oxidative stress (oxidized and reduced glutathione), histological changes using Alcian blue and hematoxylin & eosin staining and expression of IL1β, TNFα, iNOS, COX-2 were evaluated. The effect of the extract in three additional in vivo models were studied: intestinal motility and diarrhea induced by ricin oil, and visceral pain induced by intracolonic administration of capsaicin. Finally, the activity on concentration response curves of acetylcholine, calcium chloride, potassium and serotonin were achieved in isolated rat jejunum. RESULTS In the colitis model, M. verticillata induced a significant reduction in the colon weight/length ratio, oxidative stress and expression levels of IL-1β, iNOS and COX-2. Also, the extract diminished the severity of microscopic tissue damage and showed protective effect on goblet cells. Intestinal motility, diarrhea, visceral pain-related behaviors and referred hyperalgesia were significantly reduced when the animals were treated with the extract. Furthermore, in isolated jejunum, M. verticillata significantly reduced the contraction induced by serotonin and acetylcholine. Likewise, the extract non-competitively inhibited the response-concentration induced by CaCl2 and inhibited both low and high K+-induced contractions. CONCLUSIONS This is the first study to validate traditional use of M. verticillata for digestive disorders and demonstrated that its aqueous extract could represent a promising strategy in targeting the multifactorial pathophysiology of inflammatory bowel disease.
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Affiliation(s)
- A Rodríguez Basso
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Farmacología, Junín 956, C1113AAD, Buenos Aires, Argentina
| | - A Carranza
- CONICET- Universidad de Buenos Aires. Instituto Alberto C. Taquini de Investigaciones en Medicina Traslacional (IATIMET), Buenos Aires, Argentina
| | - V M Zainutti
- Hospital Interzonal de Agudos "Evita", Río de Janeiro, 1910, B1824DL, Buenos Aires, Argentina
| | - H Bach
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Farmacobotánica y Museo de Farmacobotánica, Argentina
| | - S B Gorzalczany
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Farmacología, Junín 956, C1113AAD, Buenos Aires, Argentina.
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7
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Swarte JC, Douwes RM, Hu S, Vich Vila A, Eisenga MF, van Londen M, Gomes-Neto AW, Weersma RK, Harmsen HJ, Bakker SJ. Characteristics and Dysbiosis of the Gut Microbiome in Renal Transplant Recipients. J Clin Med 2020; 9:E386. [PMID: 32024079 PMCID: PMC7074359 DOI: 10.3390/jcm9020386] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 01/26/2020] [Accepted: 01/28/2020] [Indexed: 02/07/2023] Open
Abstract
Renal transplantation is life-changing in many aspects. This includes changes to the gut microbiome likely due to exposure to immunosuppressive drugs and antibiotics. As a consequence, renal transplant recipients (RTRs) might suffer from intestinal dysbiosis. We aimed to investigate the gut microbiome of RTRs and compare it with healthy controls and to identify determinants of the gut microbiome of RTRs. Therefore, RTRs and healthy controls participating in the TransplantLines Biobank and Cohort Study (NCT03272841) were included. We analyzed the gut microbiome using 16S rRNA sequencing and compared the composition of the gut microbiome of RTRs to healthy controls using multivariate association with linear models (MaAsLin). Fecal samples of 139 RTRs (50% male, mean age: 58.3 ± 12.8 years) and 105 healthy controls (57% male, mean age: 59.2 ± 10.6 years) were collected. Median time after transplantation of RTRs was 6.0 (1.5-12.5)years. The microbiome composition of RTRs was significantly different from that of healthy controls, and RTRs had a lower diversity of the gut microbiome (p < 0.01). Proton-pump inhibitors, mycophenolate mofetil, and estimated glomerular filtration rate (eGFR) are significant determinants of the gut microbiome of RTRs (p < 0.05). Use of mycophenolate mofetil correlated to a lower diversity (p < 0.01). Moreover, significant alterations were found in multiple bacterial taxa between RTRs and healthy controls. The gut microbiome of RTRs contained more Proteobacteria and less Actinobacteria, and there was a loss of butyrate-producing bacteria in the gut microbiome of RTRs. By comparing the gut microbiome of RTRs to healthy controls we have shown that RTRs suffer from dysbiosis, a disruption in the balance of the gut microbiome.
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Affiliation(s)
- J. Casper Swarte
- Department of Internal Medicine, Division of Nephrology, University Medical Center Groningen, University of Groningen, 9700RB Groningen, The Netherlands
- Department of Gastroenterology and Hepatology, University Medical Center Groningen, University of Groningen, 9700RB Groningen, The Netherlands
| | - Rianne M. Douwes
- Department of Internal Medicine, Division of Nephrology, University Medical Center Groningen, University of Groningen, 9700RB Groningen, The Netherlands
| | - Shixian Hu
- Department of Gastroenterology and Hepatology, University Medical Center Groningen, University of Groningen, 9700RB Groningen, The Netherlands
- Department of Genetics, University Medical Center Groningen, University of Groningen, 9700RB Groningen, The Netherlands
| | - Arnau Vich Vila
- Department of Gastroenterology and Hepatology, University Medical Center Groningen, University of Groningen, 9700RB Groningen, The Netherlands
- Department of Genetics, University Medical Center Groningen, University of Groningen, 9700RB Groningen, The Netherlands
| | - Michele F. Eisenga
- Department of Internal Medicine, Division of Nephrology, University Medical Center Groningen, University of Groningen, 9700RB Groningen, The Netherlands
| | - Marco van Londen
- Department of Internal Medicine, Division of Nephrology, University Medical Center Groningen, University of Groningen, 9700RB Groningen, The Netherlands
| | - António W. Gomes-Neto
- Department of Internal Medicine, Division of Nephrology, University Medical Center Groningen, University of Groningen, 9700RB Groningen, The Netherlands
| | - Rinse K. Weersma
- Department of Gastroenterology and Hepatology, University Medical Center Groningen, University of Groningen, 9700RB Groningen, The Netherlands
| | - Hermie J.M. Harmsen
- Department of Medical Microbiology, University Medical Center Groningen, University of Groningen, 9700RB Groningen, The Netherlands
| | - Stephan J.L. Bakker
- Department of Internal Medicine, Division of Nephrology, University Medical Center Groningen, University of Groningen, 9700RB Groningen, The Netherlands
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Yasukawa Z, Inoue R, Ozeki M, Okubo T, Takagi T, Honda A, Naito Y. Effect of Repeated Consumption of Partially Hydrolyzed Guar Gum on Fecal Characteristics and Gut Microbiota: A Randomized, Double-Blind, Placebo-Controlled, and Parallel-Group Clinical Trial. Nutrients 2019; 11:E2170. [PMID: 31509971 PMCID: PMC6769658 DOI: 10.3390/nu11092170] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 08/27/2019] [Accepted: 09/02/2019] [Indexed: 02/08/2023] Open
Abstract
Partially hydrolyzed guar gum (PHGG) is a water-soluble dietary fiber and is used in solid and liquid food to regulate gut function. The aim of this study was to investigate effects of PHGG on bowel movements (stool form and frequency), plasma bile acids, quality of life, and gut microbiota of healthy volunteers with a tendency toward diarrhea, i.e., irritable bowel syndrome diarrhea (IBS-D)-like symptoms. A randomized, double-blind, placebo-controlled, and parallel trial was performed on 44 healthy volunteers (22 males, 22 females, 41.9 ± 6.3 years old (average ± SD)) with minimum 7 bowel movements every week, wherein above 50% of their stool was between the Bristol stool scale (BSS) value of 5 and 6. Intake of the PHGG for 3 months significantly improved stool form, evaluated using BSS, and had no effects on stool frequency. BSS was significantly normalized in the group consuming the PHGG compared with the placebo. Comprehensive fecal microbiome analysis by the 16S rRNA-sequence method detected significant changes in the ratio of some bacteria, such as an increase of Bifidobacterium (p < 0.05) in the PHGG group. Our results suggest that intake of PHGG improves human stool form via regulating intestinal microbiota.
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Affiliation(s)
- Zenta Yasukawa
- Nutrition Division, Taiyo Kagaku Co., Ltd., Yokkaichi, Mie 510-0844, Japan.
- Academic-Industrial Graduate School, Mie University, Tsu, Mie 514-8507, Japan.
| | - Ryo Inoue
- Laboratory of Animal Science, Department of Agricultural and Life Sciences, Kyoto Prefectural University, Kyoto 606-8522, Japan.
| | - Makoto Ozeki
- Nutrition Division, Taiyo Kagaku Co., Ltd., Yokkaichi, Mie 510-0844, Japan.
- Academic-Industrial Graduate School, Mie University, Tsu, Mie 514-8507, Japan.
| | - Tsutomu Okubo
- Nutrition Division, Taiyo Kagaku Co., Ltd., Yokkaichi, Mie 510-0844, Japan.
- Academic-Industrial Graduate School, Mie University, Tsu, Mie 514-8507, Japan.
| | - Tomohisa Takagi
- Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan.
| | - Akira Honda
- Gastroenterology, Tokyo Medical University Ibaraki Medical Center, Inashiki, Ibaraki 300-0395, Japan.
| | - Yuji Naito
- Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan.
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9
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Abstract
Inflammatory bowel diseases broadly categorized into Crohn's disease (CD) and ulcerative colitis (UC), are chronic inflammatory disorders of the gastrointestinal tract with increasing prevalence worldwide. The etiology of the disease is complex and involves a combination of genetic, environmental, immunological and gut microbial factors. Recurring and bloody diarrhea is the most prevalent and debilitating symptom in IBD. The pathogenesis of IBD-associated diarrhea is multifactorial and is essentially an outcome of mucosal damage caused by persistent inflammation resulting in dysregulated intestinal ion transport, impaired epithelial barrier function and increased accessibility of the pathogens to the intestinal mucosa. Altered expression and/or function of epithelial ion transporters and channels is the principle cause of electrolyte retention and water accumulation in the intestinal lumen leading to diarrhea in IBD. Aberrant barrier function further contributes to diarrhea via leak-flux mechanism. Mucosal penetration of enteric pathogens promotes dysbiosis and exacerbates the underlying immune system further perpetuating IBD associated-tissue damage and diarrhea. Here, we review the mechanisms of impaired ion transport and loss of epithelial barrier function contributing to diarrhea associated with IBD.
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Affiliation(s)
- Arivarasu N Anbazhagan
- a Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago , Chicago , IL , USA
| | - Shubha Priyamvada
- a Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago , Chicago , IL , USA
| | - Waddah A Alrefai
- a Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago , Chicago , IL , USA.,b Jesse Brown VA Medical Center , Chicago , IL , USA
| | - Pradeep K Dudeja
- a Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago , Chicago , IL , USA.,b Jesse Brown VA Medical Center , Chicago , IL , USA
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10
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Thomas S, Izard J, Walsh E, Batich K, Chongsathidkiet P, Clarke G, Sela DA, Muller AJ, Mullin JM, Albert K, Gilligan JP, DiGuilio K, Dilbarova R, Alexander W, Prendergast GC. The Host Microbiome Regulates and Maintains Human Health: A Primer and Perspective for Non-Microbiologists. Cancer Res 2017; 77:1783-1812. [PMID: 28292977 PMCID: PMC5392374 DOI: 10.1158/0008-5472.can-16-2929] [Citation(s) in RCA: 215] [Impact Index Per Article: 30.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 12/19/2016] [Accepted: 12/21/2016] [Indexed: 02/07/2023]
Abstract
Humans consider themselves discrete autonomous organisms, but recent research is rapidly strengthening the appreciation that associated microorganisms make essential contributions to human health and well being. Each person is inhabited and also surrounded by his/her own signature microbial cloud. A low diversity of microorganisms is associated with a plethora of diseases, including allergy, diabetes, obesity, arthritis, inflammatory bowel diseases, and even neuropsychiatric disorders. Thus, an interaction of microorganisms with the host immune system is required for a healthy body. Exposure to microorganisms from the moment we are born and appropriate microbiome assembly during childhood are essential for establishing an active immune system necessary to prevent disease later in life. Exposure to microorganisms educates the immune system, induces adaptive immunity, and initiates memory B and T cells that are essential to combat various pathogens. The correct microbial-based education of immune cells may be critical in preventing the development of autoimmune diseases and cancer. This review provides a broad overview of the importance of the host microbiome and accumulating knowledge of how it regulates and maintains a healthy human system. Cancer Res; 77(8); 1783-812. ©2017 AACR.
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Affiliation(s)
- Sunil Thomas
- Lankenau Institute for Medical Research, Wynnewood, Pennsylvania.
| | - Jacques Izard
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, Nebraska
| | - Emily Walsh
- Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, Massachusetts
| | - Kristen Batich
- Department of Neurosurgery, Duke Brain Tumor Immunotherapy Program, Duke University Medical Center, Durham, North Carolina
- Department of Surgery, Duke Brain Tumor Immunotherapy Program, Duke University Medical Center, Durham, North Carolina
- Department of Pathology, Duke University Medical Center, Durham, North Carolina
| | - Pakawat Chongsathidkiet
- Department of Neurosurgery, Duke Brain Tumor Immunotherapy Program, Duke University Medical Center, Durham, North Carolina
- Department of Surgery, Duke Brain Tumor Immunotherapy Program, Duke University Medical Center, Durham, North Carolina
- Department of Pathology, Duke University Medical Center, Durham, North Carolina
| | - Gerard Clarke
- Department of Psychiatry and Neurobehavioural Science, APC Microbiome Institute University College Cork, Cork, Ireland
| | - David A Sela
- Department of Food Science, University of Massachusetts, Amherst, Massachusetts
- Department of Microbiology, University of Massachusetts, Amherst, Massachusetts
- Center for Microbiome Research, University of Massachusetts Medical School, Worcester, Massachusetts
| | | | - James M Mullin
- Lankenau Institute for Medical Research, Wynnewood, Pennsylvania
| | - Korin Albert
- Molecular and Cellular Biology Graduate Program, University of Massachusetts, Amherst, Massachusetts
- Department of Food Science, University of Massachusetts, Amherst, Massachusetts
| | - John P Gilligan
- Lankenau Institute for Medical Research, Wynnewood, Pennsylvania
| | | | - Rima Dilbarova
- Lankenau Institute for Medical Research, Wynnewood, Pennsylvania
| | - Walker Alexander
- Lankenau Institute for Medical Research, Wynnewood, Pennsylvania
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11
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Priyamvada S, Gomes R, Gill RK, Saksena S, Alrefai WA, Dudeja PK. Mechanisms Underlying Dysregulation of Electrolyte Absorption in Inflammatory Bowel Disease-Associated Diarrhea. Inflamm Bowel Dis 2015; 21:2926-35. [PMID: 26595422 PMCID: PMC4662046 DOI: 10.1097/mib.0000000000000504] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Inflammatory bowel diseases (IBDs), including Crohn's disease and ulcerative colitis, are chronic relapsing inflammatory disorders of the gastrointestinal tract. Chronic inflammation of the intestine affects the normal fluid and electrolyte absorption leading to diarrhea, the hallmark symptom of IBD. The management of IBD-associated diarrhea still remains to be a challenge, and extensive studies over the last 2 decades have focused on investigating the molecular mechanisms underlying IBD-associated diarrhea. These studies have shown that the predominant mechanism of diarrhea in IBD involves impairment of electroneutral NaCl absorption, with very little role if any played by anion secretion. The electroneutral NaCl absorption involves coupled operation of Na/H exchanger 3 (NHE3 or SLC9A3) and Cl/HCO3 exchanger DRA (Down Regulated in Adenoma, or SLC26A3). Increasing evidence now supports the critical role of a marked decrease in NHE3 and DRA function and/or expression in IBD-associated diarrhea. This review provides a detailed analysis of the current knowledge related to alterations in NHE3 and DRA function and expression in IBD including the mechanisms underlying these observations and highlights the potential of these transporters as important and novel therapeutic targets.
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Affiliation(s)
- Shubha Priyamvada
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, IL
| | - Rochelle Gomes
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, IL
| | - Ravinder K. Gill
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, IL
| | - Seema Saksena
- Jesse Brown VA Medical Center, University of Illinois at Chicago, Chicago, IL
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, IL
| | - Waddah A. Alrefai
- Jesse Brown VA Medical Center, University of Illinois at Chicago, Chicago, IL
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, IL
| | - Pradeep K. Dudeja
- Jesse Brown VA Medical Center, University of Illinois at Chicago, Chicago, IL
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, IL
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12
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Arora K, Sinha C, Zhang W, Moon CS, Ren A, Yarlagadda S, Dostmann WR, Adebiyi A, Haberman Y, Denson LA, Wang X, Naren AP. Altered cGMP dynamics at the plasma membrane contribute to diarrhea in ulcerative colitis. THE AMERICAN JOURNAL OF PATHOLOGY 2015; 185:2790-804. [PMID: 26261085 DOI: 10.1016/j.ajpath.2015.06.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Revised: 05/31/2015] [Accepted: 06/29/2015] [Indexed: 12/19/2022]
Abstract
Ulcerative colitis (UC) belongs to inflammatory bowel disorders, a group of gastrointestinal disorders that can produce serious recurring diarrhea in affected patients. The mechanism for UC- and inflammatory bowel disorder-associated diarrhea is not well understood. The cystic fibrosis transmembrane-conductance regulator (CFTR) chloride channel plays an important role in fluid and water transport across the intestinal mucosa. CFTR channel function is regulated in a compartmentalized manner through the formation of CFTR-containing macromolecular complexes at the plasma membrane. In this study, we demonstrate the involvement of a novel macromolecular signaling pathway that causes diarrhea in UC. We found that a nitric oxide-producing enzyme, inducible nitric oxide synthase (iNOS), is overexpressed under the plasma membrane and generates compartmentalized cGMP in gut epithelia in UC. The scaffolding protein Na(+)/H(+) exchanger regulatory factor 2 (NHERF2) bridges iNOS with CFTR, forming CFTR-NHERF2-iNOS macromolecular complexes that potentiate CFTR channel function via the nitric oxide-cGMP pathway under inflammatory conditions both in vitro and in vivo. Potential disruption of these complexes in Nherf2(-/-) mice may render them more resistant to CFTR-mediated secretory diarrhea than Nherf2(+/+) mice in murine colitis models. Our study provides insight into the mechanism of pathophysiologic occurrence of diarrhea in UC and suggests that targeting CFTR and CFTR-containing macromolecular complexes will ameliorate diarrheal symptoms and improve conditions associated with inflammatory bowel disorders.
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Affiliation(s)
- Kavisha Arora
- Division of Pulmonary Medicine, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio; Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Chandrima Sinha
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Weiqiang Zhang
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee; Department of Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Chang Suk Moon
- Division of Pulmonary Medicine, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio; Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Aixia Ren
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Sunitha Yarlagadda
- Division of Pulmonary Medicine, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio; Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
| | | | - Adebowale Adebiyi
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Yael Haberman
- Division of Gastroenterology, Hepatology, and Nutrition, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Lee A Denson
- Division of Gastroenterology, Hepatology, and Nutrition, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Xusheng Wang
- Department of Structural Biology and Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, Tennessee
| | - Anjaparavanda P Naren
- Division of Pulmonary Medicine, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio; Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee.
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13
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Abstract
Bile acid malabsorption (BAM) is a common but an underestimated and often neglected sign of inflammatory bowel diseases (IBDs), especially those affecting the distal ileum. Clinically relevant BAM is most often present in patients with Crohn's ileitis and particularly in ileal-resected Crohn's disease patients. However, deterioration of bile acid (BA) metabolism occurs also in patients with IBD without ileal disease or in those in clinical remission, and the role of BAM in these patients is not well appreciated by clinicians. In a majority of cases, BAM in IBD is caused by impaired conjugated BA reabsorption, mediated by apical sodium/BA cotransporting polypeptide, localized at the luminal surface of the ileal enterocytes. As a consequence, numerous pathological sequelae may occur, including the malfunction of lipid digestion with clinical steatorrhea, impaired intestinal motility, and/or significant changes in the intestinal microflora environment. In this review, a detailed description of the pathophysiological mechanisms of BAM-related diarrhea is presented. Although BAM is present in a significant number of patients with Crohn's disease, its laboratory assessment is not routinely included in diagnostic workups, partially because of costs, logistical reasons, or the unavailability of the more sophisticated laboratory equipment needed. Simultaneously, novel findings related to the effects of the BA signaling pathways on immune functions (mediated through TGR5, cell membrane G protein-coupled BA receptor 1, nuclear farnesoid X receptor, nuclear pregnane X receptor, or nuclear vitamin D receptor) are discussed along with intestinal metabolism in its relationship to the pathogenesis of IBD.
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14
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Abstract
The epithelium of the gastrointestinal tract is one of the most versatile tissues in the organism, responsible for providing a tight barrier between dietary and bacterial antigens and the mucosal and systemic immune system while maintaining efficient digestive and absorptive processes to ensure adequate nutrient and energy supply. Inflammatory bowel diseases (Crohn's disease and ulcerative colitis) are associated with a breakdown of both functions, which in some cases are clearly interrelated. In this updated literature review, we focus on the effects of intestinal inflammation and the associated immune mediators on selected aspects of the transepithelial transport of macronutrients and micronutrients. The mechanisms responsible for nutritional deficiencies are not always clear and could be related to decreased intake, malabsorption, and excess losses. We summarize the known causes of nutrient deficiencies and the mechanism of inflammatory bowel disease-associated diarrhea. We also overview the consequences of impaired epithelial transport, which infrequently transcend its primary purpose to affect the gut microbial ecology and epithelial integrity. Although some of those regulatory mechanisms are relatively well established, more work needs to be done to determine how inflammatory cytokines can alter the transport process of nutrients across the gastrointestinal and renal epithelia.
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Santiago A, Panda S, Mengels G, Martinez X, Azpiroz F, Dore J, Guarner F, Manichanh C. Processing faecal samples: a step forward for standards in microbial community analysis. BMC Microbiol 2014; 14:112. [PMID: 24884524 PMCID: PMC4021188 DOI: 10.1186/1471-2180-14-112] [Citation(s) in RCA: 109] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Accepted: 04/25/2014] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND The microbial community analysis of stools requires optimised and standardised protocols for their collection, homogenisation, microbial disruption and nucleic acid extraction. Here we examined whether different layers of the stool are equally representative of the microbiome. We also studied the effect of stool water content, which typically increases in diarrhoeic samples, and of a microbial disruption method on DNA integrity and, therefore, on providing an unbiased microbial composition analysis. RESULTS We collected faecal samples from healthy subjects and performed microbial composition analysis by pyrosequencing the V4 region of the 16S rRNA gene. To examine the effect of stool structure, we compared the inner and outer layers of the samples (N = 8). Both layers presented minor differences in microbial composition and abundance at the species level. These differences did not significantly bias the microbial community specific to an individual. To evaluate the effect of stool water content and bead-beating, we used various volumes of a water-based salt solution and beads of distinct weights before nucleic acid extraction (N = 4). The different proportions of water did not affect the UniFrac-based clustering of samples from the same subject However, the use or omission of a bead-beating step produced different proportions of Gram-positive and Gram-negative bacteria and significant changes in the UniFrac-based clustering of the samples. CONCLUSION The degree of hydration and homogenisation of faecal samples do not significantly alter their microbial community composition. However, the use of bead-beating is critical for the proper detection of Gram-positive bacteria such as Blautia and Bifidobacterium.
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Affiliation(s)
| | | | | | | | | | | | | | - Chaysavanh Manichanh
- Vall d'Hebron Research Institute, Digestive System Research Unit, Passeig de la Vall d'Hebron 119-129, Barcelona 08035, Spain.
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16
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Antonioli L, Colucci R, Pellegrini C, Giustarini G, Tuccori M, Blandizzi C, Fornai M. The role of purinergic pathways in the pathophysiology of gut diseases: pharmacological modulation and potential therapeutic applications. Pharmacol Ther 2013; 139:157-88. [PMID: 23588157 DOI: 10.1016/j.pharmthera.2013.04.002] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Accepted: 03/15/2013] [Indexed: 02/08/2023]
Abstract
Gut homeostasis results from complex neuro-immune interactions aimed at triggering stereotypical and specific programs of coordinated mucosal secretion and powerful motor propulsion. A prominent role in the regulation of this highly integrated network, comprising a variety of immune/inflammatory cells and the enteric nervous system, is played by purinergic mediators. The cells of the digestive tract are literally plunged into a "biological sea" of functionally active nucleotides and nucleosides, which carry out the critical task of driving regulatory interventions on cellular functions through the activation of P1 and P2 receptors. Intensive research efforts are being made to achieve an integrated view of the purinergic system, since it is emerging that the various components of purinergic pathways (i.e., enzymes, transporters, mediators and receptors) are mutually linked entities, deputed to finely modulating the magnitude and the duration of purinergic signaling, and that alterations occurring in this balanced network could be intimately involved in the pathophysiology of several gut disorders. This review article intends to provide a critical appraisal of current knowledge on the purinergic system role in the regulation of gastrointestinal functions, considering these pathways as a whole integrated network, which is capable of finely controlling the levels of bioactive nucleotides and nucleosides in the biophase of their respective receptors. Special attention is paid to the mechanisms through which alterations in the various compartments of the purinergic system could contribute to the pathophysiology of gut disorders, and to the possibility of counteracting such dysfunctions by means of pharmacological interventions on purinergic molecular targets.
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Affiliation(s)
- Luca Antonioli
- Department of Clinical and Experimental Medicine, University of Pisa, Italy.
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