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Amiri M, Jiang M, Salari A, Xiu R, Alper SL, Seidler UE. Reduced surface pH and upregulated AE2 anion exchange in SLC26A3-deleted polarized intestinal epithelial cells. Am J Physiol Cell Physiol 2024; 326:C829-C842. [PMID: 38223928 PMCID: PMC11193482 DOI: 10.1152/ajpcell.00590.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 12/21/2023] [Accepted: 01/02/2024] [Indexed: 01/16/2024]
Abstract
Loss of function mutations in the SLC26A3 gene cause chloride-losing diarrhea in mice and humans. Although systemic adaptive changes have been documented in these patients and in the corresponding knockout mice, how colonic enterocytes adapt to loss of this highly expressed and highly regulated luminal membrane anion exchanger remains unclear. To address this question, SLC26A3 was deleted in the self-differentiating Caco2BBe colonic cell line by the CRISPR/Cas9 technique. We selected a clone with loss of SLC26A3 protein expression and morphological features indistinguishable from those of the native cell line. Neither growth curves nor development of transepithelial electrical resistance (TEER) differed between wild-type (WT) and SLC26A3 knockout (KO) cells. Real-time qPCR and Western analysis in SLC26A3-KO cells revealed an increase in AE2 expression without significant change in NHE3 expression or localization. Steady-state pHi and apical and basolateral Cl-/HCO3- exchange activities were assessed fluorometrically in a dual perfusion chamber with independent perfusion of luminal and serosal baths. Apical Cl-/HCO3- exchange rates were strongly reduced in SLC26A3-KO cells, accompanied by a surface pH more acidic than that of WT cells. Steady-state pHi was not significantly different from that of WT cells, but basolateral Cl-/HCO3- exchange rates were higher in SLC26A3-KO than in WT cells. The data show that CRISPR/Cas9-mediated SLC26A3 deletion strongly reduced apical Cl-/HCO3- exchange rate and apical surface pH, but sustained a normal steady-state pHi due to increased expression and function of basolateral AE2. The low apical surface pH resulted in functional inhibition of NHE-mediated fluid absorption despite normal expression of NHE3 polypeptide.NEW & NOTEWORTHY SLC26A3 gene mutations cause chloride-losing diarrhea. To understand how colonic enterocytes adapt, SLC26A3 was deleted in Caco2BBe cells using CRISPR/Cas9. In comparison to the wild-type cells, SLC26A3 knockout cells showed similar growth and transepithelial resistance but substantially reduced apical Cl-/HCO3- exchange rates, and an acidic surface pH. Steady-state intracellular pH was comparable between the WT and KO cells due to increased basolateral AE2 expression and function.
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Affiliation(s)
- Mahdi Amiri
- Department of Gastroenterology, Hannover Medical School, Hannover, Germany
| | - Min Jiang
- Department of Gastroenterology, Hannover Medical School, Hannover, Germany
| | - Azam Salari
- Department of Gastroenterology, Hannover Medical School, Hannover, Germany
| | - Renjie Xiu
- Department of Gastroenterology, Hannover Medical School, Hannover, Germany
| | - Seth L Alper
- Division of Nephrology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, United States
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States
| | - Ursula E Seidler
- Department of Gastroenterology, Hannover Medical School, Hannover, Germany
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Guo Y, Li X, Geng C, Song S, Xie X, Wang C. Vitamin D receptor involves in the protection of intestinal epithelial barrier function via up-regulating SLC26A3. J Steroid Biochem Mol Biol 2023; 227:106231. [PMID: 36462760 DOI: 10.1016/j.jsbmb.2022.106231] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Revised: 05/13/2022] [Accepted: 07/15/2022] [Indexed: 12/05/2022]
Abstract
BACKGROUND Vitamin D receptor (VDR) and SLC26A3 (DRA) have been identified as pivotal protective factors in maintaining gut homeostasis in IBD patients. However, the specific mechanism underlying the increased intestinal susceptibility to inflammation induced by the loss of VDR and whether DRA participates in the role of VDR regulating intestinal epithelial barrier function are undefined. AIM The current study is undertaken to elucidate the regulatory effects of VDR on DRA and VDR prevents intestinal epithelial barrier dysfunction via up-regulating the expression of DRA. METHODS WT and VDR-/- mice are used as models for intestinal epithelial response. Paracellular permeability is measured by TEER and FD-4 assays. Immunohistochemistry, immunofluorescence, qPCR and immunoblotting are performed to determine the effects of VDR and DRA on gut epithelial barrier function. RESULTS VDR-/- mice exhibits significant hyperpermeability of intestine with greatly decreased levels of ZO-1 and Claudin1 proteins. DRA is located on the intestinal epithelial apical membrane and is tightly modulated by VDR in vivo and in vitro via activating ERK1/2 MAPK signaling pathway. Notably, the current study for the first time demonstrates that VDR maintains intestinal epithelial barrier integrity via up-regulating DRA expression and the lack of DRA induced by VDR knockdown leads to a more susceptive condition for intestine to DSS-induced colitis. CONCLUSION Our study provides evidence and deep comprehension regarding the role of VDR in modulating DRA expression in gut homeostasis and makes novel contributions to better generally understanding the links between VDR, DRA and intestinal epithelial barrier function.
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Affiliation(s)
- Yaoyu Guo
- Department of Gastroenterology, West China Hospital of Sichuan University, Chengdu, China
| | - Xiao Li
- Department of Gastroenterology, West China Hospital of Sichuan University, Chengdu, China
| | - Chong Geng
- Department of Gastroenterology, West China Hospital of Sichuan University, Chengdu, China
| | - Shuailing Song
- Department of Gastroenterology, West China Hospital of Sichuan University, Chengdu, China
| | - Xiaoxi Xie
- Department of Gastroenterology, West China Hospital of Sichuan University, Chengdu, China
| | - Chunhui Wang
- Department of Gastroenterology, West China Hospital of Sichuan University, Chengdu, China.
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Shao YF, Wang H, Wang YX, Shao LP, Wang S. Prenatal diagnosis of congenital chloride diarrhea by whole exome sequencing in four Chinese families and prenatal genotype-phenotype association study. World J Pediatr 2023; 19:200-207. [PMID: 36417080 DOI: 10.1007/s12519-022-00634-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Accepted: 10/06/2022] [Indexed: 11/24/2022]
Affiliation(s)
- Ying-Fei Shao
- Renji College of Wenzhou Medical University, Wenzhou, China
- Department of Nephrology, The Affiliated Qingdao Municipal Hospital of Qingdao University, No.5 Donghai Middle Road, Qingdao, 266071, China
- Laboratory of Renal Disease, Qingdao, China
| | - Hong Wang
- Department of Nephrology, Eighth People's Hospital of Qingdao, Qingdao, China
| | - Yi-Xiu Wang
- Darpartment of Hepatic Surgery, Shanghai Cancer Center, Shanghai Medical College, Fudan University, Shanghai, China
| | - Le-Ping Shao
- Department of Nephrology, The Affiliated Qingdao Municipal Hospital of Qingdao University, No.5 Donghai Middle Road, Qingdao, 266071, China.
- Laboratory of Renal Disease, Qingdao, China.
| | - Sai Wang
- Department of Nephrology, The Affiliated Qingdao Municipal Hospital of Qingdao University, No.5 Donghai Middle Road, Qingdao, 266071, China.
- Department of Dermatology, Peking University First Hospital, Beijing, China.
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The rs12532734 Polymorphism Near the Solute Carrier 26A3 Gene Locus Is Associated With Gallstone Disease in Children. J Pediatr Gastroenterol Nutr 2022; 75:692-694. [PMID: 36084219 DOI: 10.1097/mpg.0000000000003609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Gallstones are increasingly frequent in children. In this candidate gene study, we genotyped 5 gene variants ( ANO1 , SPTLC3 , TMEM147 , TNRC6B , rs12532734) from a recent gallstone genome-wide association study (GWAS) in a cohort of 214 children with gallstones and 172 gallstone-free adult controls. In total, 138 genotyped children presented with symptomatic gallstone disease, 47 underwent cholecystectomy, and 126 received ursodeoxycholic acid (UDCA) as therapy for stones. Among 5 tested variants, the rs12532734 polymorphism modulated the gallstone risk in the studied cohort. Its genotype distribution significantly ( P = 0.025) departed from the Hardy-Weinberg equilibrium among cases, and the common allele was associated with increased odds of developing gallstones at young age (OR = 1.69, P = 0.014). SLC26A3 is the nearest gene to rs12532734 and is involved in the transepithelial bicarbonate and chloride transport. The association of rs12532734 with pediatric gallstones is a novel finding warranting further investigations also with regard to biliary bicarbonate flux and bile composition.
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Zhang T, Zhu T, Wen J, Chen Y, Wang L, Lv X, Yang W, Jia Y, Qu C, Li H, Wang H, Qu L, Ning Z. Gut microbiota and transcriptome analysis reveals a genetic component to dropping moisture in chickens. Poult Sci 2022; 102:102242. [PMID: 36931071 PMCID: PMC10036737 DOI: 10.1016/j.psj.2022.102242] [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: 12/09/2021] [Revised: 06/11/2022] [Accepted: 06/14/2022] [Indexed: 03/12/2023] Open
Abstract
High dropping moisture (DM) in poultry production has deleterious effects on the environment, feeding cost, and public health of people and animals. To explore the contributing genetic components, we classified DM of 67-wk-old Rhode Island Red (RIR) hens at 4 different levels and evaluated the underlying genetic heritability. We found the heritability of DM to be 0.219, indicating a moderately heritable trait. We then selected chickens with the highest and lowest DM levels. Using transcriptome, we only detected 12 differentially expressed genes (DEGs) between these 2 groups from the spleen, and 1,507 DEGs from intestinal tissues (jejunum and cecum). The low number of DEGs observed in the spleen suggests that differing moisture levels are not attributed to pathogenic infection. Fourteen of the intestinal high expressed genes are associated with water-salt metabolism (WSM). We also investigated the gut microbial composition by 16S rRNA gene amplicon sequencing. Six different microbial operational taxonomic units (OTUs) (Cetobacterium, Sterolibacterium, Elusimicrobium, Roseburia, Faecalicoccus, and Megamonas) between the 2 groups from jejunum and cecum are potentially biomarkers related to DM levels. Our results identify a genetic component to chicken DM, and can guide breeding strategies.
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Affiliation(s)
- Tongyu Zhang
- State Key Laboratory of Animal Nutrition, Department of Animal Genetics and Breeding, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Tao Zhu
- State Key Laboratory of Animal Nutrition, Department of Animal Genetics and Breeding, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Junhui Wen
- State Key Laboratory of Animal Nutrition, Department of Animal Genetics and Breeding, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Yu Chen
- Beijing Animal Husbandry and Veterinary Station, Beijing, China
| | - Liang Wang
- Beijing Animal Husbandry and Veterinary Station, Beijing, China
| | - Xueze Lv
- Beijing Animal Husbandry and Veterinary Station, Beijing, China
| | - Weifang Yang
- Beijing Animal Husbandry and Veterinary Station, Beijing, China
| | - Yaxiong Jia
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Changqing Qu
- Engineering Technology Research Center of Anti-aging Chinese Herbal Medicine of Anhui Province, Fuyang Normal University, Fuyang, China
| | - Haiying Li
- College of Animal Science, Xinjiang Agricultural University, Urumqi, China
| | - Huie Wang
- College of Animal Science, Tarim University, Xinjiang, China
| | - Lujiang Qu
- State Key Laboratory of Animal Nutrition, Department of Animal Genetics and Breeding, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China.
| | - Zhonghua Ning
- State Key Laboratory of Animal Nutrition, Department of Animal Genetics and Breeding, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China.
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Sun Y, Leng C, van Ijzendoorn SCD. Fetal Bowel Abnormalities Suspected by Ultrasonography in Microvillus Inclusion Disease: Prevalence and Clinical Significance. J Clin Med 2022; 11:jcm11154331. [PMID: 35893420 PMCID: PMC9332086 DOI: 10.3390/jcm11154331] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 06/28/2022] [Accepted: 07/22/2022] [Indexed: 02/01/2023] Open
Abstract
Microvillus inclusion disease (MVID) is a rare, inherited, congenital, diarrheal disorder that is invariably fatal if left untreated. Within days after birth, MVID presents as a life-threatening emergency characterized by severe dehydration, metabolic acidosis, and weight loss. Diagnosis is cumbersome and can take a long time. Whether MVID could be diagnosed before birth is not known. Anecdotal reports of MVID-associated fetal bowel abnormalities suspected by ultrasonography (that is, dilated bowel loops and polyhydramnios) have been published. These are believed to be rare, but their prevalence in MVID has not been investigated. Here, we have performed a comprehensive retrospective study of 117 published MVID cases spanning three decades. We find that fetal bowel abnormalities in MVID occurred in up to 60% of cases of MVID for which prenatal ultrasonography or pregnancy details were reported. Suspected fetal bowel abnormalities appeared in the third trimester of pregnancy and correlated with postnatal, early-onset diarrhea and case-fatality risk during infancy. Fetal bowel dilation correlated with MYO5B loss-of-function variants. In conclusion, MVID has already started during fetal life in a significant number of cases. Genetic testing for MVID-causing gene variants in cases where fetal bowel abnormalities are suspected by ultrasonography may allow for the prenatal diagnosis of MVID in a significant percentage of cases, enabling optimal preparation for neonatal intensive care.
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Affiliation(s)
- Yue Sun
- Department of Biomedical Sciences of Cells and Systems, Section Molecular Cell Biology, University of Groningen, University Medical Center Groningen, 9713 AV Groningen, The Netherlands; (Y.S.); (C.L.)
- Center for Liver, Digestive & Metabolic Disease, University of Groningen, University Medical Center Groningen, 9700 AD Groningen, The Netherlands
| | - Changsen Leng
- Department of Biomedical Sciences of Cells and Systems, Section Molecular Cell Biology, University of Groningen, University Medical Center Groningen, 9713 AV Groningen, The Netherlands; (Y.S.); (C.L.)
- Center for Liver, Digestive & Metabolic Disease, University of Groningen, University Medical Center Groningen, 9700 AD Groningen, The Netherlands
- State Key Laboratory of Oncology in South China, Collaborative Innovation Centre for Cancer Medicine, Guangdong Esophageal Cancer Institute, Department of Thoracic Surgery, Sun Yat-sen University Cancer Centre, Guangzhou 510060, China
| | - Sven C. D. van Ijzendoorn
- Department of Biomedical Sciences of Cells and Systems, Section Molecular Cell Biology, University of Groningen, University Medical Center Groningen, 9713 AV Groningen, The Netherlands; (Y.S.); (C.L.)
- Center for Liver, Digestive & Metabolic Disease, University of Groningen, University Medical Center Groningen, 9700 AD Groningen, The Netherlands
- Correspondence:
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Cavarocchi E, Whitfield M, Saez F, Touré A. Sperm Ion Transporters and Channels in Human Asthenozoospermia: Genetic Etiology, Lessons from Animal Models, and Clinical Perspectives. Int J Mol Sci 2022; 23:ijms23073926. [PMID: 35409285 PMCID: PMC8999829 DOI: 10.3390/ijms23073926] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 03/29/2022] [Accepted: 03/30/2022] [Indexed: 12/18/2022] Open
Abstract
In mammals, sperm fertilization potential relies on efficient progression within the female genital tract to reach and fertilize the oocyte. This fundamental property is supported by the flagellum, an evolutionarily conserved organelle that provides the mechanical force for sperm propulsion and motility. Importantly several functional maturation events that occur during the journey of the sperm cells through the genital tracts are necessary for the activation of flagellar beating and the acquisition of fertilization potential. Ion transporters and channels located at the surface of the sperm cells have been demonstrated to be involved in these processes, in particular, through the activation of downstream signaling pathways and the promotion of novel biochemical and electrophysiological properties in the sperm cells. We performed a systematic literature review to describe the currently known genetic alterations in humans that affect sperm ion transporters and channels and result in asthenozoospermia, a pathophysiological condition defined by reduced or absent sperm motility and observed in nearly 80% of infertile men. We also present the physiological relevance and functional mechanisms of additional ion channels identified in the mouse. Finally, considering the state-of-the art, we discuss future perspectives in terms of therapeutics of asthenozoospermia and male contraception.
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Affiliation(s)
- Emma Cavarocchi
- Institute for Advanced Biosciences, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, 38000 Grenoble, France; (E.C.); (M.W.)
| | - Marjorie Whitfield
- Institute for Advanced Biosciences, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, 38000 Grenoble, France; (E.C.); (M.W.)
| | - Fabrice Saez
- UMR GReD Institute (Génétique Reproduction & Développement) CNRS 6293, INSERM U1103, Team «Mécanismes de L’Infertilité Mâle Post-Testiculaire», Université Clermont Auvergne, 63000 Clermont-Ferrand, France
- Correspondence: (F.S.); (A.T.)
| | - Aminata Touré
- Institute for Advanced Biosciences, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, 38000 Grenoble, France; (E.C.); (M.W.)
- Correspondence: (F.S.); (A.T.)
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Meng Y, Li Y, Fang D, Huang Y. Identification of solute carrier family genes related to the prognosis and tumor-infiltrating immune cells of pancreatic ductal adenocarcinoma. ANNALS OF TRANSLATIONAL MEDICINE 2022; 10:57. [PMID: 35282128 PMCID: PMC8848431 DOI: 10.21037/atm-21-6341] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 12/23/2021] [Indexed: 12/24/2022]
Abstract
Background Pancreatic ductal adenocarcinoma (PDAC) has persisted as one of the worst prognostic tumors with a 5-year survival rate of lower than 6%. Although many studies have investigated PDAC, new biomarkers are required to ensure early diagnosis and predict the prognosis of PDAC. Methods In this study, we used bioinformatics methods to evaluate differences in the expression of solute carrier (SLC) family genes in tumors and non-tumors. A Kaplan-Meier analysis, least absolute shrinkage and selection operator (LASSO) analysis, and multivariate Cox proportional hazards regression analysis were used to evaluate the relationship between SLC genes and prognosis using The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets. The prognostic signature was constructed depending on the risk score to assess the impact of multiple genes on the prognosis, receiver operating characteristic (ROC) curves and forest plot was constructed to assess the ability to predict the prognosis and effects of clinical variables in both high- and low-risk groups. Tumor-infiltrating immune cells were evaluated using Cell-type Identification by Estimating Relative Subsets of RNA Transcripts (CIBERSORT) in both high- and low-risk groups. Results In 32 SLC genes, 9 were significantly associated with the OS after LASSO analysis. SLC19A3 (P=0.007), SLC25A39 (P=0.027), SLC39A11 (P=0.043) were significantly associated with prognosis and included into the prognostic model. CIBERSORT demonstrated that memory B cells (P=0.004), naive B cells (P=0.007), CD8 T cells (P=0.003), activated memory CD4 T cells (P=0.004), and activated NK cells (P=0.019) were significantly higher in the low-risk group. Gene set enrichment analysis (GSEA) showed that potential molecular mechanisms enriched in MYC and p53 signaling pathways. Conclusions SLC19A3, SLC25A35, and SLC39A11 were significantly relative to the prognosis of PDAC and changed the tumor microenvironment, as well as the MYC and p53 signaling pathways. The SLC19A3 gene may represent a new tumor suppressor in PDAC.
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Affiliation(s)
- Yuhua Meng
- Department of Glandular Surgery, the People's Hospital of Baise, Baise, China
| | - Yanting Li
- Department of Glandular Surgery, the People's Hospital of Baise, Baise, China
| | - Dalang Fang
- Department of Breast and Thyroid Surgery, The Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, China
| | - Yuanlu Huang
- Department of Glandular Surgery, the People's Hospital of Baise, Baise, China
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Cao D, Xu N, Chen Y, Zhang H, Li Y, Yuan Z. Construction of a Pearson- and MIC-Based Co-expression Network to Identify Potential Cancer Genes. Interdiscip Sci 2021; 14:245-257. [PMID: 34694561 DOI: 10.1007/s12539-021-00485-w] [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: 04/23/2021] [Revised: 09/29/2021] [Accepted: 09/30/2021] [Indexed: 11/26/2022]
Abstract
The weighted gene co-expression network analysis (WGCNA) method constructs co-expressed gene modules based on the linear similarity between paired gene expressions. Linear correlations are the main form of similarity between genes, however, nonlinear correlations still existed and had always been ignored. We proposed a modified network analysis method, WGCNA-P + M, which combines Pearson's correlation coefficient and the maximum information coefficient (MIC) as the similarity measures to assess the linear and nonlinear correlations between genes, respectively. Taking two real datasets, GSE44861 and liver hepatocellular carcinoma (TCGA-LIHC), as examples, we compared the gene modules constructed by WGCNA-P + M and WGCNA from four perspectives: the "Usefulness" score, GO enrichment analysis on genes in the gray module, prediction performance of the top hub gene, survival analysis and literature reports on different hub genes. The results showed that the modules obtained by WGCNA-P + M are more biological meaningful, the hub genes obtained from WGCNA-P + M have more potential cancer genes.
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Affiliation(s)
- Dan Cao
- Hunan Engineering and Technology Research Center for Agricultural Big Data Analysis and Decision-Making, Hunan Agricultural University, Changsha, 410128, Hunan, China
- College of Science, Central South University of Forestry and Technology, Changsha, 410004, Hunan, China
| | - Na Xu
- Hunan Engineering and Technology Research Center for Agricultural Big Data Analysis and Decision-Making, Hunan Agricultural University, Changsha, 410128, Hunan, China
| | - Yuan Chen
- Hunan Engineering and Technology Research Center for Agricultural Big Data Analysis and Decision-Making, Hunan Agricultural University, Changsha, 410128, Hunan, China
| | - Hongyan Zhang
- Hunan Engineering and Technology Research Center for Agricultural Big Data Analysis and Decision-Making, Hunan Agricultural University, Changsha, 410128, Hunan, China
| | - Yuting Li
- Hunan Engineering and Technology Research Center for Agricultural Big Data Analysis and Decision-Making, Hunan Agricultural University, Changsha, 410128, Hunan, China
| | - Zheming Yuan
- Hunan Engineering and Technology Research Center for Agricultural Big Data Analysis and Decision-Making, Hunan Agricultural University, Changsha, 410128, Hunan, China.
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Yan W, Xiao Y, Zhang Y, Tao Y, Cao Y, Liu K, Cai W, Wang Y. Monogenic mutations in four cases of neonatal-onset watery diarrhea and a mutation review in East Asia. Orphanet J Rare Dis 2021; 16:383. [PMID: 34503561 PMCID: PMC8427875 DOI: 10.1186/s13023-021-01995-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 07/25/2021] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Infants with neonatal-onset diarrhea present with intractable diarrhea in the first few weeks of life. A monogenic mutation is one of the disease etiologies and the use of next-generation sequencing (NGS) has made it possible to screen patients for their mutations. MAIN BODY We retrospectively reviewed the clinical data of four children from unrelated families, who presented with neonatal-onset, chronic, watery, non-bloody diarrhea. After genetic whole-exome sequencing, novel mutations were identified in the EPCAM gene of two children. Congenital chloride diarrhea was diagnosed in one case, which was associated with an SLC26A3 mutation, in which the patient presented with watery diarrhea, malnutrition, and hypochloremic alkalosis. Patient 4 was diagnosed with microvillus inclusion disease and possessed novel compound heterozygous mutations in the MYO5B gene. A review of the genetic variants of SLC26A3 reported in East Asia revealed that c.269_270 dupAA (p.G91Kfs*3) is the most frequent SLC26A3 mutation in China, compared with c.2063-1 G > T in Japan and Korea. EPCAM and MYO5B genetic variants were only sporadically reported in East Asia. CONCLUSION This study expands our knowledge of the clinical manifestations and molecular genetics of neonatal-onset watery diarrhea. Early diagnosis could be achieved by genomic analysis in those infants whose histology features are not typical. The discovery of four novel mutations in the EPCAM gene and two novel mutations in the MYO5B gene provides further etiological evidence for the association of genetic mutations with neonatal-onset diarrhea. To date, c.269_270 dupAA is the most frequent SLC26A3 mutation in China.
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Affiliation(s)
- Weihui Yan
- Division of Pediatric Gastroenterology and Nutrition, Xinhua Hospital Affiliated To Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
- Shanghai Key Laboratory of Pediatric Gastroenterology and Nutrition, Shanghai, People's Republic of China
- Innovative Research Team of High-Level Local Universities in Shanghai, Shanghai, People's Republic of China
| | - Yongtao Xiao
- Shanghai Institute for Pediatric Research, Shanghai, People's Republic of China
- Shanghai Key Laboratory of Pediatric Gastroenterology and Nutrition, Shanghai, People's Republic of China
- Innovative Research Team of High-Level Local Universities in Shanghai, Shanghai, People's Republic of China
| | - Yunyi Zhang
- Shanghai Institute for Pediatric Research, Shanghai, People's Republic of China
- Shanghai Key Laboratory of Pediatric Gastroenterology and Nutrition, Shanghai, People's Republic of China
| | - Yijing Tao
- Division of Pediatric Gastroenterology and Nutrition, Xinhua Hospital Affiliated To Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
| | - Yi Cao
- Division of Pediatric Gastroenterology and Nutrition, Xinhua Hospital Affiliated To Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
| | - Kunhui Liu
- Department of Pediatric Surgery, Xinhua Hospital Affiliated To Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
| | - Wei Cai
- Shanghai Institute for Pediatric Research, Shanghai, People's Republic of China.
- Department of Pediatric Surgery, Xinhua Hospital Affiliated To Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China.
- Shanghai Key Laboratory of Pediatric Gastroenterology and Nutrition, Shanghai, People's Republic of China.
- Innovative Research Team of High-Level Local Universities in Shanghai, Shanghai, People's Republic of China.
- Xinhua Hospital Affiliated To Shanghai Jiao Tong University School of Medicine, No.1665, Kong Jiang Road, Yangpu, Shanghai, 200092, People's Republic of China.
| | - Ying Wang
- Division of Pediatric Gastroenterology and Nutrition, Xinhua Hospital Affiliated To Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China.
- Shanghai Key Laboratory of Pediatric Gastroenterology and Nutrition, Shanghai, People's Republic of China.
- Innovative Research Team of High-Level Local Universities in Shanghai, Shanghai, People's Republic of China.
- Xinhua Hospital Affiliated To Shanghai Jiao Tong University School of Medicine, No.1665, Kong Jiang Road, Yangpu, Shanghai, 200092, People's Republic of China.
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Zheng HB, de la Morena MT, Suskind DL. The Growing Need to Understand Very Early Onset Inflammatory Bowel Disease. Front Immunol 2021; 12:675186. [PMID: 34122435 PMCID: PMC8187749 DOI: 10.3389/fimmu.2021.675186] [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: 03/02/2021] [Accepted: 05/04/2021] [Indexed: 11/24/2022] Open
Abstract
Very Early Onset Inflammatory Bowel Disease (VEO-IBD) represents a cohort of inflammatory bowel disease (IBD) patients diagnosed before 6 years of age. Unlike IBD diagnosed at older ages, VEO-IBD can be associated with underlying primary immunodeficiencies. VEO-IBD has been linked to monogenic variations in over 70 genes involved in multiple pathways of immunity. As sequencing technologies and platforms evolve and become readily available, an increasing number of genes linked to VEO-IBD have emerged. Although monogenic defects are rare in VEO-IBD, diagnosis of these variants can often dictate specific treatment. In this mini-review, we set out to describe monogenic variants previously characterized in multiple patients in the literature that contribute to VEO-IBD, diagnostic tools, unique treatment modalities for specific genetic diagnoses, and future directions in the field of VEO-IBD. Although this mini-review is by no means comprehensive of all the novel monogenic variants linked to VEO-IBD, we hope to provide relevant information that is readily accessible to clinicians and educators.
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Affiliation(s)
- Hengqi B Zheng
- Division of Gastroenterology and Hepatology, Seattle Children's Hospital, Seattle, WA, United States.,Department of Pediatrics, University of Washington, Seattle, WA, United States
| | - M Teresa de la Morena
- Department of Pediatrics, University of Washington, Seattle, WA, United States.,Division of Immunology, Seattle Children's Hospital, Seattle, WA, United States
| | - David L Suskind
- Division of Gastroenterology and Hepatology, Seattle Children's Hospital, Seattle, WA, United States.,Department of Pediatrics, University of Washington, Seattle, WA, United States
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12
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Rahman MM, Afroz S, Arthur S, Sundaram U. Mast Cell Mediated Regulation of Small Intestinal Chloride Malabsorption in SAMP1/YitFc Mouse Model of Spontaneous Chronic Ileitis. Cells 2021; 10:cells10030697. [PMID: 33801010 PMCID: PMC8004028 DOI: 10.3390/cells10030697] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Revised: 03/13/2021] [Accepted: 03/18/2021] [Indexed: 12/19/2022] Open
Abstract
In Inflammatory Bowel Disease (IBD), malabsorption of electrolytes (NaCl) results in diarrhea. Inhibition of coupled NaCl absorption, mediated by the dual operation of Na:H and Cl:HCO3 exchangers on the brush border membrane (BBM) of the intestinal villus cells has been reported in IBD. In the SAMP1/YitFcs (SAMP1) mice model of spontaneous ileitis, representing Crohn’s disease, DRA (Downregulated in Adenoma) mediated Cl:HCO3 exchange was shown to be inhibited secondary to diminished affinity of the exchanger for Cl. However, NHE3 mediated Na:H exchange remained unaffected. Mast cells and their secreted mediators are known to be increased in the IBD mucosa and can affect intestinal electrolyte absorption. However, how mast cell mediators may regulate Cl:HCO3 exchange in SAMP1 mice is unknown. Therefore, the aim of this study was to determine the effect of mast cell mediators on the downregulation of DRA in SAMP1 mice. Mast cell numbers and their degranulation marker enzyme (β-hexosaminidase) levels were significantly increased in SAMP1 mice compared to control AKR mice. However, treatment of SAMP1 mice with a mast cell stabilizer, ketotifen, restored the β-hexosaminidase enzyme levels to normal in the intestine, demonstrating stabilization of mast cells by ketotifen. Moreover, downregulation of Cl:HCO3 exchange activity was restored in ketotifen treated SAMP1 mice. Kinetic studies showed that ketotifen restored the altered affinity of Cl:HCO3 exchange in SAMP1 mice villus cells thus reinstating its activity to normal. Further, RT-qPCR, Western blot and immunofluorescence studies showed that the expression levels of DRA mRNA and BBM protein, respectively remained unaltered in all experimental conditions, supporting the kinetic data. Thus, inhibition of Cl:HCO3 exchange resulting in chloride malabsorption leading to diarrhea in IBD is likely mediated by mast cell mediators.
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13
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Yu Q. Slc26a3 (DRA) in the Gut: Expression, Function, Regulation, Role in Infectious Diarrhea and Inflammatory Bowel Disease. Inflamm Bowel Dis 2021; 27:575-584. [PMID: 32989468 DOI: 10.1093/ibd/izaa256] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND The transport of transepithelial Cl- and HCO3- is crucial for the function of the intestinal epithelium and maintains the acid-based homeostasis. Slc26a3 (DRA), as a key chloride-bicarbonate exchanger protein in the intestinal epithelial luminal membrane, participates in the electroneutral NaCl absorption of intestine, together with Na+/H+ exchangers. Increasing recent evidence supports the essential role of decreased DRA function or expression in infectious diarrhea and inflammatory bowel disease (IBD). METHOD In this review, we give an overview of the current knowledge of Slc26a3, including its cloning and expression, function, roles in infectious diarrhea and IBD, and mechanisms of actions. A better understanding of the physiological and pathophysiological relevance of Slc26a3 in infectious diarrhea and IBD may reveal novel targets for future therapy. CONCLUSION Understanding the physiological function, regulatory interactions, and the potential mechanisms of Slc26a3 in the pathophysiology of infectious diarrhea and IBD will define novel therapeutic approaches in future.
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Affiliation(s)
- Qin Yu
- Department of Gastroenterology, Tongji Hospital, Huazhong University of Science and Technology, Wuhan City, China
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14
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Kumar A, Priyamvada S, Ge Y, Jayawardena D, Singhal M, Anbazhagan AN, Chatterjee I, Dayal A, Patel M, Zadeh K, Saksena S, Alrefai WA, Gill RK, Zadeh M, Zhao N, Mohamadzadeh M, Dudeja PK. A Novel Role of SLC26A3 in the Maintenance of Intestinal Epithelial Barrier Integrity. Gastroenterology 2021; 160:1240-1255.e3. [PMID: 33189700 PMCID: PMC7956241 DOI: 10.1053/j.gastro.2020.11.008] [Citation(s) in RCA: 59] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 11/02/2020] [Accepted: 11/03/2020] [Indexed: 02/08/2023]
Abstract
BACKGROUND & AIMS The down-regulated in adenoma (DRA) protein, encoded by SLC26A3, a key intestinal chloride anion exchanger, has recently been identified as a novel susceptibility gene for inflammatory bowel disease (IBD). However, the mechanisms underlying the increased susceptibility to inflammation induced by the loss of DRA remain elusive. Compromised barrier is a key event in IBD pathogenesis. The current studies were undertaken to elucidate the impact of DRA deficiency on epithelial barrier integrity and to define underlying mechanisms. METHODS Wild-type and DRA-knockout (KO) mice and crypt-derived colonoids were used as models for intestinal epithelial response. Paracellular permeability was measured by using fluorescein isothiocyanate-dextran flux. Immunoblotting, immunofluorescence, immunohistochemistry, and ribonucleoprotein immunoprecipitation assays were performed. Gut microbiome analysis was conducted to investigate the impact of DRA deficiency on gut microbial communities. RESULTS DRA-KO mice exhibited an increased colonic paracellular permeability with significantly decreased levels of tight junction/adherens junction proteins, including ZO-1, occludin, and E-cadherin. A similar expression pattern of occludin and E-cadherin was observed in colonoids derived from DRA-KO mice and short hairpin RNA-mediated DRA knockdown in Caco-2 cells. Microbial analysis showed gut dysbiosis in DRA-KO mice. However, cohousing studies showed that dysbiosis played only a partial role in maintaining tight junction protein expression. Furthermore, our results showed increased binding of RNA-binding protein CUGBP1 with occludin and E-cadherin genes in DRA-KO mouse colon, suggesting that posttranscriptional mechanisms play a key role in gut barrier dysfunction. CONCLUSIONS To our knowledge, our studies demonstrate a novel role of DRA in maintaining the intestinal epithelial barrier function and potential implications of its dysregulation in IBD pathogenesis.
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Affiliation(s)
- Anoop Kumar
- Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois; Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Shubha Priyamvada
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Yong Ge
- Department of Infectious Diseases and Immunology and Division of Gastroenterology, Hepatology and Nutrition, Department of Medicine, University of Florida, Gainesville, Florida
| | - Dulari Jayawardena
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Megha Singhal
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Arivarasu N Anbazhagan
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Ishita Chatterjee
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Aneal Dayal
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Mitul Patel
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Kimia Zadeh
- Department of Infectious Diseases and Immunology and Division of Gastroenterology, Hepatology and Nutrition, Department of Medicine, University of Florida, Gainesville, Florida
| | - Seema Saksena
- Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois; Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Waddah A Alrefai
- Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois; Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Ravinder K Gill
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Mojgan Zadeh
- Department of Infectious Diseases and Immunology and Division of Gastroenterology, Hepatology and Nutrition, Department of Medicine, University of Florida, Gainesville, Florida
| | - Ni Zhao
- Department of Infectious Diseases and Immunology and Division of Gastroenterology, Hepatology and Nutrition, Department of Medicine, University of Florida, Gainesville, Florida
| | - Mansour Mohamadzadeh
- Department of Infectious Diseases and Immunology and Division of Gastroenterology, Hepatology and Nutrition, Department of Medicine, University of Florida, Gainesville, Florida
| | - Pradeep K Dudeja
- Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois; Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois.
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15
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Yin J, Sunuwar L, Kasendra M, Yu H, Tse CM, Talbot CC, Boronina T, Cole R, Karalis K, Donowitz M. Fluid shear stress enhances differentiation of jejunal human enteroids in Intestine-Chip. Am J Physiol Gastrointest Liver Physiol 2021; 320:G258-G271. [PMID: 33074011 PMCID: PMC8202237 DOI: 10.1152/ajpgi.00282.2020] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
There is increasing evidence that the study of normal human enteroids duplicates many known aspects of human intestinal physiology. However, this epithelial cell-only model lacks the many nonepithelial intestinal cells present in the gastrointestinal tract and exposure to the mechanical forces to which the intestine is exposed. We tested the hypothesis that physical shear forces produced by luminal and blood flow would provide an intestinal model more closely resembling normal human jejunum. Jejunal enteroid monolayers were studied in the Emulate, Inc. Intestine-Chip under conditions of constant luminal and basolateral flow that was designed to mimic normal intestinal fluid flow, with human umbilical vein endothelial cells (HUVECs) on the basolateral surface and with Wnt3A, R-spondin, and Noggin only on the luminal surface. The jejunal enteroids formed monolayers that remained confluent for 6-8 days, began differentiating at least as early as day 2 post plating, and demonstrated continuing differentiation over the entire time of the study, as shown by quantitative real-time polymerase chain reaction and Western blot analysis. Differentiation impacted villus genes and proteins differently with early expression of regenerating family member 1α (REG1A), early reduction to a low but constant level of expression of Na+-K+-2Cl- cotransporter 1 (NKCC1), and increasing expression of sucrase-isomaltase (SI) and downregulated in adenoma (DRA). These results were consistent with continual differentiation, as was shown to occur in mouse villus enterocytes. Compared with differentiated enteroid monolayers grown on Transwell inserts, enteroids exposed to flow were more differentiated but exhibited increased apoptosis and reduced carbohydrate metabolism, as shown by proteomic analysis. This study of human jejunal enteroids-on-chip suggests that luminal and basolateral flow produce a model of continual differentiation over time and NaCl absorption that mimics normal intestine and should provide new insights in intestinal physiology.NEW & NOTEWORTHY This study showed that polarized enteroid models in which there is no basolateral Wnt3a, are differentiated, regardless of the Wnt3a status of the apical media. The study supports the concept that in the human intestine villus differentiation is not an all or none phenomenon, demonstrating that at different days after lack of basolateral Wnt exposure, clusters of genes and proteins exist geographically along the villus with different domains having different functions.
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Affiliation(s)
- Jianyi Yin
- 1Department of Medicine, Division of Gastroenterology and Hepatology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Laxmi Sunuwar
- 1Department of Medicine, Division of Gastroenterology and Hepatology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | | | - Huimin Yu
- 1Department of Medicine, Division of Gastroenterology and Hepatology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Chung-Ming Tse
- 1Department of Medicine, Division of Gastroenterology and Hepatology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - C. Conover Talbot
- 3Institute for Basic Biomedical Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Tatiana Boronina
- 4Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Robert Cole
- 4Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Katia Karalis
- 2Emulate, Inc., Boston, Massachusetts,5Biomedical Sciences Research Center (BSRC) Alexander Fleming, Vari, Greece,7Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Mark Donowitz
- 1Department of Medicine, Division of Gastroenterology and Hepatology, Johns Hopkins University School of Medicine, Baltimore, Maryland,7Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland
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16
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Konishi KI, Mizuochi T, Honma H, Etani Y, Morikawa K, Wada K, Yamamoto K. A novel de novo SLC26A3 mutation causing congenital chloride diarrhea in a Japanese neonate. Mol Genet Genomic Med 2020; 8:e1505. [PMID: 32951339 PMCID: PMC7667310 DOI: 10.1002/mgg3.1505] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 08/27/2020] [Accepted: 08/31/2020] [Indexed: 01/06/2023] Open
Abstract
Background Congenital chloride diarrhea (CCD) is characterized by persistent chloride (Cl)‐rich diarrhea evident from birth. CCD is a rare autosomal recessive disorder caused by defects in the solute carrier family 26 member 3 (SLC26A3) gene, which encodes an intestinal Cl−/HCO3−, Na+‐independent exchanger. Various mutations of SLC26A3 have been described in CCD. However, no de novo mutations have been found to be responsible for CCD. Here we report the first such occurrence. Methods Clinical and laboratory findings during the perinatal period were obtained retrospectively from medical records. Mutations involving SLC26A3 were detected by Sanger sequencing. Results The male infant reported here was delivered at 29 weeks of gestation. Just after birth, he had watery diarrhea without meconium passage. High chloride concentrations in the diarrhea led to a diagnosis of CCD. Direct sequencing of all coding exons in SLC26A3 including exon‐intron boundaries disclosed 2 compound heterozygous mutations: c.382G>A, p.G128S and c.2063‐1g>t. The c. 2063‐1g>t mutation was confirmed in his mother's DNA, but c.382G>A, p.G128S was absent in both mother and father. Conclusion We concluded that c.382G>A, p.G128S represented a de novo mutation of SLC26A3, a very rare event in autosomal recessive disorders. To our knowledge, this is the first CCD case involving a de novo novel mutation of SLC26A3.
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Affiliation(s)
- Ken-Ichiro Konishi
- Department of Pediatrics and Child Health, Kurume University School of Medicine, Kurume, Japan.,Department of Pediatric Surgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Tatsuki Mizuochi
- Department of Pediatrics and Child Health, Kurume University School of Medicine, Kurume, Japan
| | - Hitoshi Honma
- Department of Gastroenterology and Endocrinology, Osaka Women's and Children's Hospital, Osaka, Japan
| | - Yuri Etani
- Department of Gastroenterology and Endocrinology, Osaka Women's and Children's Hospital, Osaka, Japan
| | - Kazue Morikawa
- Department of Neonatal Medicine, Osaka Women's and Children's Hospital, Osaka, Japan
| | - Kazuko Wada
- Department of Neonatal Medicine, Osaka Women's and Children's Hospital, Osaka, Japan
| | - Ken Yamamoto
- Department of Medical Biochemistry, Kurume University School of Medicine, Kurume, Japan
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17
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Kelsen JR, Sullivan KE, Rabizadeh S, Singh N, Snapper S, Elkadri A, Grossman AB. North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition Position Paper on the Evaluation and Management for Patients With Very Early-onset Inflammatory Bowel Disease. J Pediatr Gastroenterol Nutr 2020; 70:389-403. [PMID: 32079889 DOI: 10.1097/mpg.0000000000002567] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The rate of pediatric inflammatory bowel disease (IBD) has been increasing over the last decade and this increase has occurred most rapidly in the youngest children diagnosed <6 years, known as very early-onset inflammatory bowel disease (VEO-IBD). These children can present with more extensive and severe disease than older children and adults. The contribution of host genetics in this population is underscored by the young age of onset and the distinct, aggressive phenotype. In fact, monogenic defects, often involving primary immunodeficiency genes, have been identified in children with VEO-IBD and have led to targeted and life-saving therapy. This position paper will discuss the phenotype of VEO-IBD and outline the approach and evaluation for these children and what factors should trigger concern for an underlying immunodeficiency. We will then review the immunological assays and genetic studies that can facilitate the identification of the underlying diagnosis in patients with VEO-IBD and how this evaluation may lead to directed therapies. The position paper will also aid the pediatric gastroenterologist in recognizing when a patient should be referred to a center specializing in the care of these patients. These guidelines are intended for pediatricians, allied health professionals caring for children, pediatric gastroenterologists, pediatric pathologists, and immunologists.
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Affiliation(s)
| | - Kathleen E Sullivan
- Division of Immunology and Allergy, Children's Hospital of Philadelphia, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Shervin Rabizadeh
- Division of Gastroenterology, Hepatology, and Nutrition, Cedar-Sinai Medical Center, Los Angeles, CA
| | - Namita Singh
- Division of Gastroenterology, Department of Pediatrics, Seattle Children's Hospital, University of Washington, Seattle, WA
| | - Scott Snapper
- Division of Gastroenterology, Hepatology, and Nutrition, Boston Children's Hospital, Department of Pediatrics, Harvard Medical School
- Division of Gastroenterology, Department of Medicine, Brigham & Women's Hospital and Harvard Medical School, Boston, MA
| | - Abdul Elkadri
- Division of Gastroenterology, Hepatology, and Nutrition, Medical College of Wisconsin, Milwaukee, WI
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18
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Kurteva E, Lindley KJ, Hill SM, Köglmeier J. Mucosal Abnormalities in Children With Congenital Chloride Diarrhea-An Underestimated Phenotypic Feature? Front Pediatr 2020; 8:365. [PMID: 32850522 PMCID: PMC7403178 DOI: 10.3389/fped.2020.00365] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Accepted: 06/01/2020] [Indexed: 01/12/2023] Open
Abstract
Objectives and Study: Congenital chloride diarrhea (CCD) is a rare, autosomal recessive disorder caused by mutations in the SLC26A3 gene encoding a transmembrane chloride/bicarbonate ion exchanger mainly expressed in the apical brush border of the ileal and colonic epithelium. Lifelong, secretory, chloride-rich diarrhea and hypochloremic, hypokalemic metabolic alkalosis are characteristic. Histological evidence of bowel inflammation is not typically described in CCD and has only been reported in a few patients. Methods: We report four cases of CCD who received adequate resuscitation with appropriate replacement of their fecal salt and water losses. Three had associated inflammatory bowel changes at endoscopy. The index case of CCD who developed frankly bloodstained diarrhea aged 7 months was found to have histologically confirmed colitis at endoscopy. An electronic search of the hospital database to identify all patients with confirmed CCD was performed. A further three children underwent de novo diagnostic evaluation and treatment. A retrospective case note review was undertaken to determine the incidence and subtype of inflammatory bowel disease (IBD) by clinical, endoscopic, and histological means. Results: Four children with genetically confirmed CCD were identified, two being female. The first girl had a granulomatous colitis with ulceration. She went into remission with a combination of steroids and azathioprine. Immunosuppression was subsequently discontinued without a further flare of colitis. A second girl was found to have patchy inflammatory changes in the small bowel and focal active colitis. A third patient, a boy, demonstrated mild inflammatory changes in the small bowel with apoptotic debris and mild inflammation in the colon. A fourth patient did not develop intestinal inflammation. Conclusion: Our case series highlights the potential association of CCD with panenteric inflammation. While our cohort was small, CCD is rare and three out of four children referred to our tertiary referral center were affected. While early diagnosis and adequate salt replacement therapy are crucial in CCD management, the clinician should also be aware of bowel inflammation as a potential cause of failure of CCD therapy to control bowel symptomatology. Further insight is needed to understand the underlying patho-mechanism giving rise to bowel inflammation in this group.
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Affiliation(s)
- Elena Kurteva
- Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
| | - Keith J Lindley
- Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
| | - Susan M Hill
- Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
| | - Jutta Köglmeier
- Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
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19
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Jayawardena D, Alrefai WA, Dudeja PK, Gill RK. Recent advances in understanding and managing malabsorption: focus on microvillus inclusion disease. F1000Res 2019; 8. [PMID: 31824659 PMCID: PMC6896243 DOI: 10.12688/f1000research.20762.1] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/29/2019] [Indexed: 12/11/2022] Open
Abstract
Microvillus inclusion disease (MVID) is a rare congenital severe malabsorptive and secretory diarrheal disease characterized by blunted or absent microvilli with accumulation of secretory granules and inclusion bodies in enterocytes. The typical clinical presentation of the disease is severe chronic diarrhea that rapidly leads to dehydration and metabolic acidosis. Despite significant advances in our understanding of the causative factors, to date, no curative therapy for MVID and associated diarrhea exists. Prognosis mainly relies on life-long total parenteral nutrition (TPN) and eventual small bowel and/or liver transplantation. Both TPN and intestinal transplantation are challenging and present with many side effects. A breakthrough in the understanding of MVID emanated from seminal findings revealing mutations in
MYO5B as a cause for MVID. During the last decade, many studies have thus utilized cell lines and animal models with knockdown of
MYO5B to closely recapitulate the human disease and investigate potential therapeutic options in disease management. We will review the most recent advances made in the research pertaining to MVID. We will also highlight the tools and models developed that can be utilized for basic and applied research to increase our understanding of MVID and develop novel and effective targeted therapies.
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Affiliation(s)
- Dulari Jayawardena
- Division of Gastroenterology & Hepatology, University of Illinois at Chicago, Chicago, IL, USA
| | - Waddah A Alrefai
- Division of Gastroenterology & Hepatology, University of Illinois at Chicago, Chicago, IL, USA.,Jesse Brown VA Medical Center, Chicago, IL, USA
| | - Pradeep K Dudeja
- Division of Gastroenterology & Hepatology, University of Illinois at Chicago, Chicago, IL, USA.,Jesse Brown VA Medical Center, Chicago, IL, USA
| | - Ravinder K Gill
- Division of Gastroenterology & Hepatology, University of Illinois at Chicago, Chicago, IL, USA
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20
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Walther B, Lett AM, Bordoni A, Tomás‐Cobos L, Nieto JA, Dupont D, Danesi F, Shahar DR, Echaniz A, Re R, Fernandez AS, Deglaire A, Gille D, Schmid A, Vergères G. GutSelf: Interindividual Variability in the Processing of Dietary Compounds by the Human Gastrointestinal Tract. Mol Nutr Food Res 2019; 63:e1900677. [PMID: 31483113 PMCID: PMC6900003 DOI: 10.1002/mnfr.201900677] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 07/25/2019] [Indexed: 12/19/2022]
Abstract
Nutritional research is currently entering the field of personalized nutrition, to a large extent driven by major technological breakthroughs in analytical sciences and biocomputing. An efficient launching of the personalized approach depends on the ability of researchers to comprehensively monitor and characterize interindividual variability in the activity of the human gastrointestinal tract. This information is currently not available in such a form. This review therefore aims at identifying and discussing published data, providing evidence on interindividual variability in the processing of the major nutrients, i.e., protein, fat, carbohydrates, vitamins, and minerals, along the gastrointestinal tract, including oral processing, intestinal digestion, and absorption. Although interindividual variability is not a primary endpoint of most studies identified, a significant number of publications provides a wealth of information on this topic for each category of nutrients. This knowledge remains fragmented, however, and understanding the clinical relevance of most of the interindividual responses to food ingestion described in this review remains unclear. In that regard, this review has identified a gap and sets the base for future research addressing the issue of the interindividual variability in the response of the human organism to the ingestion of foods.
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Affiliation(s)
- Barbara Walther
- AgroscopeFederal Department of Economic AffairsEducation and Research EAER3003BerneSwitzerland
| | - Aaron M. Lett
- Section for Nutrition ResearchDepartment of MedicineImperial College LondonLondonUK
| | - Alessandra Bordoni
- Department of Agri‐Food Sciences and TechnologiesUniversity of Bologna47521CesenaItaly
| | | | | | - Didier Dupont
- UMR 1253Science et Technologie du Lait et de l'ŒufINRA35000RennesFrance
| | - Francesca Danesi
- Department of Agri‐Food Sciences and TechnologiesUniversity of Bologna47521CesenaItaly
| | - Danit R. Shahar
- Department of Public HealthThe S. Daniel Abraham International Center for Health and NutritionBen‐Gurion University of the Negev84105Beer‐ShevaIsrael
| | - Ana Echaniz
- Cambridge Food Science LtdCB23 5ABCambridgeUK
| | - Roberta Re
- Cambridge Food Science LtdCB23 5ABCambridgeUK
| | | | - Amélie Deglaire
- UMR 1253Science et Technologie du Lait et de l'ŒufINRA35000RennesFrance
| | - Doreen Gille
- AgroscopeFederal Department of Economic AffairsEducation and Research EAER3003BerneSwitzerland
| | - Alexandra Schmid
- AgroscopeFederal Department of Economic AffairsEducation and Research EAER3003BerneSwitzerland
| | - Guy Vergères
- AgroscopeFederal Department of Economic AffairsEducation and Research EAER3003BerneSwitzerland
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21
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Konishi KI, Mizuochi T, Yanagi T, Watanabe Y, Ohkubo K, Ohga S, Maruyama H, Takeuchi I, Sekine Y, Masuda K, Kikuchi N, Yotsumoto Y, Ohtsuka Y, Tanaka H, Kudo T, Noguchi A, Fuwa K, Mushiake S, Ida S, Fujishiro J, Yamashita Y, Taguchi T, Yamamoto K. Clinical Features, Molecular Genetics, and Long-Term Outcome in Congenital Chloride Diarrhea: A Nationwide Study in Japan. J Pediatr 2019; 214:151-157.e6. [PMID: 31477378 DOI: 10.1016/j.jpeds.2019.07.039] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 06/26/2019] [Accepted: 07/12/2019] [Indexed: 12/23/2022]
Abstract
OBJECTIVE To clarify clinical and genetic features of Japanese children with congenital chloride diarrhea (CCD). STUDY DESIGN This was a multi-institutional, retrospective survey of 616 pediatric centers in Japan with identified patients with CCD between 2014 and 2018. Mutations involving SLC26A3 were detected by Sanger sequencing. RESULTS Thirteen patients met all entry criteria including mutations in SLC26A3, and 14 patients satisfied clinical diagnostic criteria. Homozygous or compound heterozygous mutations in SLC26A3, including 6 novel mutations, were identified in 13 of these 14 patients (93%). The most common (detected in 7 of 13) was c.2063-1g>t. Median age at diagnosis was 1 day. Nine of the patients meeting all criteria were diagnosed as neonates (69%). Median follow-up duration was 10 years. When studied, 8 patients had <5 stools daily (62%), and all had fewer than in infancy. Only 1 patient had nephrocalcinosis, and 3 (23%) had mild chronic kidney disease. Neurodevelopment was generally good; only 1 patient required special education. Five patients (38%) received long-term sodium, potassium, and chloride supplementation. CONCLUSIONS Early fetal ultrasound diagnosis and prompt long-term sodium, potassium, and chloride supplementation were common management features. Genetic analysis of SLC26A3 provided definitive diagnosis of CCD. In contrast with previously reported localities, c.2063-1g>t might be a founder mutation in East Asia.
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Affiliation(s)
- Ken-Ichiro Konishi
- Department of Pediatrics and Child Health, Kurume University School of Medicine, Kurume, Japan; Department of Pediatric Surgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Tatsuki Mizuochi
- Department of Pediatrics and Child Health, Kurume University School of Medicine, Kurume, Japan.
| | - Tadahiro Yanagi
- Department of Pediatrics and Child Health, Kurume University School of Medicine, Kurume, Japan
| | - Yoriko Watanabe
- Department of Pediatrics and Child Health, Kurume University School of Medicine, Kurume, Japan
| | - Kazuhiro Ohkubo
- Department of Pediatrics, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Shouichi Ohga
- Department of Pediatrics, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Hidehiko Maruyama
- Division of Neonatology, National Center for Child Health and Development, Tokyo, Japan
| | - Ichiro Takeuchi
- Division of Gastroenterology, National Center for Child Health and Development, Tokyo, Japan
| | - Yuji Sekine
- Department of Emergency and General Medicine, Shizuoka Children's Hospital, Shizuoka, Japan
| | - Kei Masuda
- Department of Pediatrics, Doai Memorial Hospital, Tokyo, Japan
| | - Nobuyuki Kikuchi
- Department of Pediatrics, Yokohama City Minato Red Cross Hospital, Yokohama, Japan
| | - Yuka Yotsumoto
- Department of Pediatrics, Takatsuki General Hospital, Takatsuki, Japan
| | | | - Hidenori Tanaka
- Department of Pediatrics, Komaki City Hospital, Komaki, Japan
| | - Takahiro Kudo
- Department of Pediatrics, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Atsuko Noguchi
- Department of Pediatrics, Akita University Graduate School of Medicine, Akita, Japan
| | - Kazumasa Fuwa
- Department of Pediatrics and Child Health, Nihon University School of Medicine, Tokyo, Japan
| | - Sotaro Mushiake
- Department of Pediatrics, Nara Hospital Kinki University, Ikoma, Japan
| | - Shinobu Ida
- Department of Pediatric Gastroenterology, Nutrition and Endocrinology, Osaka Women's and Children's Hospital, Osaka, Japan
| | - Jun Fujishiro
- Department of Pediatric Surgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Yushiro Yamashita
- Department of Pediatrics and Child Health, Kurume University School of Medicine, Kurume, Japan
| | - Tomoaki Taguchi
- Department of Pediatric Surgery, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Ken Yamamoto
- Department of Medical Biochemistry, Kurume University School of Medicine, Kurume, Japan
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22
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Chang YN, Jaumann EA, Reichel K, Hartmann J, Oliver D, Hummer G, Joseph B, Geertsma ER. Structural basis for functional interactions in dimers of SLC26 transporters. Nat Commun 2019; 10:2032. [PMID: 31048734 PMCID: PMC6497670 DOI: 10.1038/s41467-019-10001-w] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Accepted: 04/13/2019] [Indexed: 12/13/2022] Open
Abstract
The SLC26 family of transporters maintains anion equilibria in all kingdoms of life. The family shares a 7 + 7 transmembrane segments inverted repeat architecture with the SLC4 and SLC23 families, but holds a regulatory STAS domain in addition. While the only experimental SLC26 structure is monomeric, SLC26 proteins form structural and functional dimers in the lipid membrane. Here we resolve the structure of an SLC26 dimer embedded in a lipid membrane and characterize its functional relevance by combining PELDOR/DEER distance measurements and biochemical studies with MD simulations and spin-label ensemble refinement. Our structural model reveals a unique interface different from the SLC4 and SLC23 families. The functionally relevant STAS domain is no prerequisite for dimerization. Characterization of heterodimers indicates that protomers in the dimer functionally interact. The combined structural and functional data define the framework for a mechanistic understanding of functional cooperativity in SLC26 dimers.
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Affiliation(s)
- Yung-Ning Chang
- Institute of Biochemistry, Biocenter, Goethe University Frankfurt, Max-von-Laue Str. 9, 60438, Frankfurt am Main, Germany
| | - Eva A Jaumann
- Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt, Max-von-Laue Str. 7, 60438, Frankfurt am Main, Germany
| | - Katrin Reichel
- Department of Theoretical Biophysics, Max Planck Institute of Biophysics, Max-von-Laue Str. 3, 60438, Frankfurt am Main, Germany
| | - Julia Hartmann
- Department of Neurophysiology, Institute of Physiology and Pathophysiology, Philipps University, 35037, Marburg, Germany
| | - Dominik Oliver
- Department of Neurophysiology, Institute of Physiology and Pathophysiology, Philipps University, 35037, Marburg, Germany.,DFG Research Training Group, Membrane Plasticity in Tissue Development and Remodeling, Philipps University, GRK 2213, Philipps, Germany
| | - Gerhard Hummer
- Department of Theoretical Biophysics, Max Planck Institute of Biophysics, Max-von-Laue Str. 3, 60438, Frankfurt am Main, Germany. .,Institute of Biophysics, Goethe University Frankfurt, Max-von-Laue Str. 1, 60438, Frankfurt am Main, Germany.
| | - Benesh Joseph
- Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt, Max-von-Laue Str. 7, 60438, Frankfurt am Main, Germany. .,Institute of Biophysics, Goethe University Frankfurt, Max-von-Laue Str. 1, 60438, Frankfurt am Main, Germany.
| | - Eric R Geertsma
- Institute of Biochemistry, Biocenter, Goethe University Frankfurt, Max-von-Laue Str. 9, 60438, Frankfurt am Main, Germany.
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23
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Kamal NM, Khan HY, El-Shabrawi MH, Sherief LM. Congenital chloride losing diarrhea: A single center experience in a highly consanguineous population. Medicine (Baltimore) 2019; 98:e15928. [PMID: 31145360 PMCID: PMC6709049 DOI: 10.1097/md.0000000000015928] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Congenital chloride losing diarrhea (CCLD) is a rare type of chronic watery diarrhea due to mutations in SLC26A3 gene leading to defective chloride-bicarbonate exchanges with the resultant loss of chloride and retention of bicarbonate.We aim to define pediatric Saudi CCLD patients' characteristics to achieve prompt diagnosis, management, follow up with good quality of life, and prevention of complications in these patients.We carried retrospective data review of demographic, clinical, laboratory, radiographic, and outcome of all pediatric patients fulfilling the criteria of CCLD over 10 years from 2004 to 2014 from a single center in Taif region, Saudi Arabia.Forty-nine patients fulfilled the criteria of CCLD from 21 families with more than one affected patient in the same family in 90% of them and positive consanguinity in 91% of the cohort. Most patients were born preterm with intrauterine growth restriction and usually neonatal intensive care unit (NICU) admissions with prematurity and its complications. Thirteen patients were discharged without diagnosis of CCLD and 3 were misdiagnosed as intestinal obstruction with unnecessary surgical intervention. Many complications do existed with renal complications being the most common with three patients received renal transplantation.Prematurity with abdominal distension and stool like urine were the commonest presentation of CCLD in Saudi children. Positive consanguinity and more than one affected sibling are present in most of our cohort.High index of suspicion by clinicians is a cornerstone for early diagnosis with subsequent favorable outcome.A multicenter national incidence study of CCLD in KSA and its genetic attributes is recommended. Premarital screening should be implemented specially for consanguineous marriage.
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Affiliation(s)
- Naglaa M. Kamal
- Pediatrics and Pediatric Hepatology, Faculty of Medicine, Cairo University, Egypt
- Pediatric Hepatology and Gastroenterology, Alhada Armed Forces Hospital, Taif, KSA
| | | | | | - Laila M. Sherief
- Pediatrics and Pediatric Hematology, Faculty of Medicine, Zagazig University, Egypt
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24
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Seidler U, Nikolovska K. Slc26 Family of Anion Transporters in the Gastrointestinal Tract: Expression, Function, Regulation, and Role in Disease. Compr Physiol 2019; 9:839-872. [DOI: 10.1002/cphy.c180027] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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25
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Liaugaudiene O, Stoniene D, Kucinskiene R, Buffat C, Asmoniene V. Case Report on a Rare Disease in Lithuania: Congenital Chloride Diarrhea. J Pediatr Genet 2019; 8:24-26. [PMID: 30775050 DOI: 10.1055/s-0038-1669437] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 07/21/2018] [Indexed: 10/28/2022]
Abstract
Congenital chloride diarrhea (CCD) is a rare disease, manifesting with secretory diarrhea and life-threatening electrolyte imbalance during infancy. The early diagnosis of CCD is therefore necessary for the adequate treatment. The long-term prognosis of properly managed CCD is favorable. We present a case of complicated CCD with necrotizing enterocolitis. The child was born to nonconsanguineous parents of Lithuanian origin. CCD was suspected due to watery diarrhea, progressive hypochloremia, and high fecal chlorides. Despite oral electrolytes being prescribed, volvulus of small intestine developed requiring several surgical interventions. The clinical diagnosis of CCD was confirmed by molecular genetic testing of SLC26A3 , which revealed two Polish founder mutations in the DNA of the patient. The prevalence of CCD in Lithuanian neighbor Poland is approximately 1 in 200,000 live births. This is the first described case of CCD in Lithuania to our knowledge, leading to the suggestion that this disease may be underdiagnosed.
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Affiliation(s)
- Olga Liaugaudiene
- Department of Genetics and Molecular Medicine, Hospital of Lithuanian University of Health Sciences, Kaunas, Lithuania
| | - Dalia Stoniene
- Department of Neonatology, Hospital of Lithuanian University of Health Sciences, Kaunas, Lithuania
| | - Ruta Kucinskiene
- Department of Pediatric, Hospital of Lithuanian University of Health Sciences, Kaunas, Lithuania
| | - Christophe Buffat
- Laboratoire de Biologie Moléculaire, Hôpital de la Conception, Assistance Publique Hôpitaux de Marseille, Marseille, France
| | - Virginija Asmoniene
- Department of Genetics and Molecular Medicine, Hospital of Lithuanian University of Health Sciences, Kaunas, Lithuania
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26
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Najafi M, Kordi-Tamandani DM, Behjati F, Sadeghi-Bojd S, Bakey Z, Karimiani EG, Schüle I, Azarfar A, Schmidts M. Mimicry and well known genetic friends: molecular diagnosis in an Iranian cohort of suspected Bartter syndrome and proposition of an algorithm for clinical differential diagnosis. Orphanet J Rare Dis 2019; 14:41. [PMID: 30760291 PMCID: PMC6375149 DOI: 10.1186/s13023-018-0981-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2018] [Accepted: 12/14/2018] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Bartter Syndrome is a rare, genetically heterogeneous, mainly autosomal recessively inherited condition characterized by hypochloremic hypokalemic metabolic alkalosis. Mutations in several genes encoding for ion channels localizing to the renal tubules including SLC12A1, KCNJ1, BSND, CLCNKA, CLCNKB, MAGED2 and CASR have been identified as underlying molecular cause. No genetically defined cases have been described in the Iranian population to date. Like for other rare genetic disorders, implementation of Next Generation Sequencing (NGS) technologies has greatly facilitated genetic diagnostics and counseling over the last years. In this study, we describe the clinical, biochemical and genetic characteristics of patients from 15 Iranian families with a clinical diagnosis of Bartter Syndrome. RESULTS Age range of patients included in this study was 3 months to 6 years and all patients showed hypokalemic metabolic alkalosis. 3 patients additionally displayed hypercalciuria, with evidence of nephrocalcinosis in one case. Screening by Whole Exome Sequencing (WES) and long range PCR revealed that 12/17 patients (70%) had a deletion of the entire CLCNKB gene that was previously identified as the most common cause of Bartter Syndrome in other populations. 4/17 individuals (approximately 25% of cases) were found to suffer in fact from pseudo-Bartter syndrome resulting from congenital chloride diarrhea due to a novel homozygous mutation in the SLC26A3 gene, Pendred syndrome due to a known homozygous mutation in SLC26A4, Cystic Fibrosis (CF) due to a novel mutation in CFTR and apparent mineralocorticoid excess syndrome due to a novel homozygous loss of function mutation in HSD11B2 gene. 1 case (5%) remained unsolved. CONCLUSIONS Our findings demonstrate deletion of CLCNKB is the most common cause of Bartter syndrome in Iranian patients and we show that age of onset of clinical symptoms as well as clinical features amongst those patients are variable. Further, using WES we were able to prove that nearly 1/4 patients in fact suffered from Pseudo-Bartter Syndrome, reversing the initial clinical diagnosis with important impact on the subsequent treatment and clinical follow up pathway. Finally, we propose an algorithm for clinical differential diagnosis of Bartter Syndrome.
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Affiliation(s)
- Maryam Najafi
- Genome Research Division, Human Genetics department, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525KL, Nijmegen, The Netherlands.,Departement of Biology, University of Sistan and Baluchestan, Zahedan, Iran
| | | | - Farkhondeh Behjati
- Genetics Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | - Simin Sadeghi-Bojd
- Children and Adolescents Health Research Center, resistant tuberculosis institute, Zahedan University of Medical Sciences, Zahedan, Iran
| | - Zeineb Bakey
- Genome Research Division, Human Genetics department, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525KL, Nijmegen, The Netherlands.,Center for Pediatrics and Adolescent Medicine, Freiburg University Hospital, Freiburg University Faculty of Medicine, Mathildenstrasse 1, 79112, Freiburg, Germany
| | - Ehsan Ghayoor Karimiani
- Razavi Cancer Research, Razavi Hospital, Imam Reza International University, Mashhad, Iran.,Next Generation Genetic Polyclinic, Mashhad, Iran
| | - Isabel Schüle
- Center for Pediatrics and Adolescent Medicine, Freiburg University Hospital, Freiburg University Faculty of Medicine, Mathildenstrasse 1, 79112, Freiburg, Germany
| | - Anoush Azarfar
- Department of Pediatrics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Miriam Schmidts
- Genome Research Division, Human Genetics department, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525KL, Nijmegen, The Netherlands. .,Center for Pediatrics and Adolescent Medicine, Freiburg University Hospital, Freiburg University Faculty of Medicine, Mathildenstrasse 1, 79112, Freiburg, Germany. .,Center for Pediatrics and Adolescent Medicine, University Hospital Freiburg, 79112, Freiburg, Germany.
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27
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Dávid É, Török D, Farkas K, Nagy N, Horváth E, Kiss Z, Oroszlán G, Balogh M, Széll M. Genetic investigation confirmed the clinical phenotype of congenital chloride diarrhea in a Hungarian patient: a case report. BMC Pediatr 2019; 19:16. [PMID: 30635044 PMCID: PMC6330408 DOI: 10.1186/s12887-019-1390-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 01/02/2019] [Indexed: 01/22/2023] Open
Abstract
Background Congenital chloride diarrhea (CCD, OMIM 214700) is a rare autosomal recessively inherited condition characterized by watery diarrhea, hypochloremia and metabolic alkalosis. Mutations of the solute carrier family 26, member 3 (SLC26A3, OMIM 126650) gene are responsible for the disease. The gene encodes a transmembrane protein, which is essential for intestinal chloride absorption. Case presentation Here we report a Hungarian boy, presenting the clinical phenotype of CCD. The patient born at 32 weeks of gestation and underwent surgery for abdominal distension and intestinal obstruction related to malrotation. After recovery, electrolyte replacement therapy was necessary due to several periods of diarrhea. After exclusion of other possible causes, increased chloride concentration in the feces supported the diagnosis of CCD. The diagnosis was confirmed by molecular genetic testing. Direct sequencing revealed compound-heterozygosity for a frameshift mutation c.1295delT (p.Leu432Argfs*11) and the known Polish founder mutation c.2024_2026dupTCA (p.Ile675_Arg676insLeu). Conclusions Here we present the clinical symptoms of the first patient in Hungary diagnosed with CCD. Based on the clinical symptoms, stool analysis and genetic testing, the diagnosis of CCD was established. Our study provides expansion for the mutation spectrum of the SLC26A3 gene and the genetic background of CCD.
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Affiliation(s)
- Éva Dávid
- Department of Pediatrics, Markusovszky Teaching Hospital, Szombathely, Hungary
| | - Dóra Török
- Department of Medical Genetics, University of Szeged, Szeged, Hungary.
| | - Katalin Farkas
- Department of Medical Genetics, University of Szeged, Szeged, Hungary
| | - Nikoletta Nagy
- Department of Medical Genetics, University of Szeged, Szeged, Hungary
| | - Emese Horváth
- Department of Medical Genetics, University of Szeged, Szeged, Hungary
| | - Zsuzsanna Kiss
- Genetic Counseling Outpatient Clinic, Markusovszky Teaching Hospital, Szombathely, Hungary
| | - György Oroszlán
- Department of Pediatrics, Markusovszky Teaching Hospital, Szombathely, Hungary
| | - Márta Balogh
- Department of Pediatrics, Markusovszky Teaching Hospital, Szombathely, Hungary
| | - Márta Széll
- Department of Medical Genetics, University of Szeged, Szeged, Hungary.,MTA-SZTE Dermatological Research Group, University of Szeged, Szeged, Hungary
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28
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Nishihara K, Kato D, Suzuki Y, Kim D, Nakano M, Yajima Y, Haga S, Nakano M, Ishizaki H, Kawahara-Miki R, Kono T, Katoh K, Roh SG. Comparative transcriptome analysis of rumen papillae in suckling and weaned Japanese Black calves using RNA sequencing. J Anim Sci 2018; 96:2226-2237. [PMID: 29762736 DOI: 10.1093/jas/skx016] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 11/23/2017] [Indexed: 12/20/2022] Open
Abstract
The length and density of rumen papillae starts to increase during weaning and growth of ruminants. This significant development increases the intraruminal surface area and the efficiency of VFA (acetate, propionate, butyrate, etc.) uptake. Thus, it is important to investigate the factors controlling the growth and development of rumen papillae during weaning. This study aimed to compare the transcriptomes of rumen papillae in suckling and weaned calves. Total RNA was extracted from the rumen papillae of 10 male Japanese Black calves (5 suckling calves, 5 wk old; 5 weaned calves, 15 wk old) and used in RNA-sequencing. Transcript abundance was estimated and differentially expressed genes were identified and these data were then used in Ingenuity Pathway Analysis (IPA) to predict the major canonical pathways and upstream regulators. Among the 871 differentially expressed genes screened by IPA, 466 genes were upregulated and 405 were downregulated in the weaned group. Canonical pathway analysis showed that "atherosclerosis" was the most significant pathway, and "tretinoin," a derivative of vitamin A, was predicted as the most active upstream regulator during weaning. Analyses also predicted IgG, lipopolysaccharides, and tumor-necrosis factor-α as regulators of the microbe-epithelium interaction that activates rumen-related immune responses. The functional category and the up-regulators found in this study provide a valuable resource for studying new candidate genes related to the proliferation and development of rumen papillae from suckling to weaning Japanese Black calves.
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Affiliation(s)
- Koki Nishihara
- Laboratory of Animal Physiology, Graduate School of Agricultural Science, Tohoku University, Sendai, Miyagi, Japan
| | - Daichi Kato
- Laboratory of Animal Physiology, Graduate School of Agricultural Science, Tohoku University, Sendai, Miyagi, Japan
| | - Yutaka Suzuki
- Research Faculty of Agriculture, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Dahye Kim
- Laboratory of Animal Physiology, Graduate School of Agricultural Science, Tohoku University, Sendai, Miyagi, Japan
| | - Misato Nakano
- Laboratory of Animal Physiology, Graduate School of Agricultural Science, Tohoku University, Sendai, Miyagi, Japan
| | - Yu Yajima
- Laboratory of Animal Physiology, Graduate School of Agricultural Science, Tohoku University, Sendai, Miyagi, Japan
| | - Satoshi Haga
- Division of Grassland Farming, NARO Institute of Livestock and Grassland Science, Nasushiobara, Tochigi, Japan
| | - Miwa Nakano
- Division of Grassland Farming, NARO Institute of Livestock and Grassland Science, Nasushiobara, Tochigi, Japan
| | - Hiroshi Ishizaki
- Division of Grassland Farming, NARO Institute of Livestock and Grassland Science, Nasushiobara, Tochigi, Japan
| | - Ryouka Kawahara-Miki
- Department of Bioscience, Tokyo University of Agriculture, Sakuragaoka, Setagaya, Tokyo, Japan.,NODAI Genome Research Center, Tokyo University of Agriculture, Sakuragaoka, Setagaya, Tokyo, Japan
| | - Tomohiro Kono
- Department of Bioscience, Tokyo University of Agriculture, Sakuragaoka, Setagaya, Tokyo, Japan.,NODAI Genome Research Center, Tokyo University of Agriculture, Sakuragaoka, Setagaya, Tokyo, Japan
| | - Kazuo Katoh
- Laboratory of Animal Physiology, Graduate School of Agricultural Science, Tohoku University, Sendai, Miyagi, Japan
| | - Sang-Gun Roh
- Laboratory of Animal Physiology, Graduate School of Agricultural Science, Tohoku University, Sendai, Miyagi, Japan
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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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30
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Kumar A, Chatterjee I, Gujral T, Alakkam A, Coffing H, Anbazhagan AN, Borthakur A, Saksena S, Gill RK, Alrefai WA, Dudeja PK. Activation of Nuclear Factor-κB by Tumor Necrosis Factor in Intestinal Epithelial Cells and Mouse Intestinal Epithelia Reduces Expression of the Chloride Transporter SLC26A3. Gastroenterology 2017; 153:1338-1350.e3. [PMID: 28823863 PMCID: PMC5669803 DOI: 10.1053/j.gastro.2017.08.024] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 07/26/2017] [Accepted: 08/02/2017] [Indexed: 12/02/2022]
Abstract
BACKGROUND & AIMS Diarrhea associated with inflammatory bowel diseases has been associated with increased levels of inflammatory cytokines, including tumor necrosis factor (TNF). The intestinal mucosa of patients with inflammatory bowel diseases has reduced expression of solute carrier family 26 member 3 (SLC26A3, also called DRA). We investigated whether TNF directly affects expression of DRA in human intestinal epithelial cells (IECs) and in the intestines of mice, and studied the mechanisms of these effects. METHODS We performed quantitative reverse transcription polymerase chain reaction, immunofluorescence, and immunoblot analyses in Caco-2, HT-29, and T-84 cells human IECs cultured in 2 or 3 dimensions with or without TNF (50 ng/mL for 6-24 hours). We purified nuclear extracts and quantified nuclear factor-κB (NF-κB) activation and DNA binding. We isolated intestinal crypts from C57BL/6 mice, cultured enteroids, incubated these with TNF (50 ng/mL, 24 hours), and quantified messenger RNAs. DRA-mediated exchange of Cl- for HCO3- was measured by uptake of 125I. Expression of the NF-κB inhibitor α (IkBa) was knocked down in Caco-2 cells with small interfering RNAs. Activation of NF-κB in response to TNF was measured by luciferase reporter assays; binding of the NF-κB subunit p65 in cells was analyzed in chromatin immunoprecipitation assays. DRA promoter activity was measured in a luciferase reporter assay. C57BL/6 mice were injected with TNF (5 μg/mouse for 3-6 hours) or vehicle (control); intestines were collected and analyzed by immunofluorescence, or RNA and protein were collected from the mucosa. RESULTS Incubation of IECs with TNF reduced expression of DRA. Knockdown of NF-κB inhibitor α in IECs led to nuclear translocation of the NF-κB subunit p65 and reduced levels of DRA messenger RNA and protein. Expression of a transgene encoding p65 or p50 in IECs led to significant reductions in the promoter activity of DRA and its expression. In chromatin immunoprecipitation assays, p65 bound directly to the promoter of DRA, at the regions of -935 to -629 and -375 to -84. Injection of mice with TNF or incubation of crypt-derived enteroids with TNF reduced their expression of DRA messenger RNA and protein. CONCLUSIONS In human IECs and intestinal tissues from mice, we found TNF to activate NF-κB, which reduced expression of the Cl- / HCO3- exchanger DRA (SLC26A3), via direct binding to the promoter of DRA. This pathway is an important therapeutic target for inflammatory bowel disease-associated diarrhea.
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Affiliation(s)
- Anoop Kumar
- Division of Gastroenterology and Hepatology, University of Illinois at Chicago, Chicago, Illinois
| | - Ishita Chatterjee
- Division of Gastroenterology and Hepatology, University of Illinois at Chicago, Chicago, Illinois
| | - Tarunmeet Gujral
- Division of Gastroenterology and Hepatology, University of Illinois at Chicago, Chicago, Illinois
| | - Anas Alakkam
- Division of Gastroenterology and Hepatology, University of Illinois at Chicago, Chicago, Illinois
| | - Hayley Coffing
- Department of Microbiology and Immunology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Arivarasu N Anbazhagan
- Division of Gastroenterology and Hepatology, University of Illinois at Chicago, Chicago, Illinois
| | - Alip Borthakur
- Division of Gastroenterology and Hepatology, University of Illinois at Chicago, Chicago, Illinois
| | - Seema Saksena
- Division of Gastroenterology and Hepatology, University of Illinois at Chicago, Chicago, Illinois; Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
| | - Ravinder K Gill
- Division of Gastroenterology and Hepatology, University of Illinois at Chicago, Chicago, Illinois
| | - Waddah A Alrefai
- Division of Gastroenterology and Hepatology, University of Illinois at Chicago, Chicago, Illinois; Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
| | - Pradeep K Dudeja
- Division of Gastroenterology and Hepatology, University of Illinois at Chicago, Chicago, Illinois; Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois.
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Chatterjee I, Kumar A, Castilla-Madrigal RM, Pellon-Cardenas O, Gill RK, Alrefai WA, Borthakur A, Verzi M, Dudeja PK. CDX2 upregulates SLC26A3 gene expression in intestinal epithelial cells. Am J Physiol Gastrointest Liver Physiol 2017; 313:G256-G264. [PMID: 28572085 PMCID: PMC5625132 DOI: 10.1152/ajpgi.00108.2017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 05/26/2017] [Accepted: 05/26/2017] [Indexed: 01/31/2023]
Abstract
SLC26A3 [downregulated in adenoma (DRA)] plays a key role in mammalian intestinal NaCl absorption, in that it mediates apical membrane Cl-/[Formula: see text] exchange. DRA function and expression are significantly decreased in diarrhea associated with inflammatory bowel disease. DRA is also considered to be a marker of cellular differentiation and is predominantly expressed in differentiated epithelial cells. Caudal-type homeobox protein-2 (CDX2) is known to regulate genes involved in intestinal epithelial differentiation and proliferation. Reduced expression of both DRA and CDX2 in intestinal inflammation prompted us to study whether the DRA gene is directly regulated by CDX2. Our initial studies utilizing CDX2 knockout (CDX2fV/fV;Cre+) mice showed a marked reduction in DRA mRNA and protein levels in proximal and distal colon. In silico analysis of the DRA promoter showed two consensus sites for CDX2 binding. Therefore, we utilized Caco-2 cells as an in vitro model to examine if DRA is a direct target of CDX2 regulation. siRNA-mediated silencing of CDX2 in Caco-2 cells resulted in a marked (~50%) decrease in DRA mRNA and protein levels, whereas ectopic overexpression of CDX2 upregulated DRA expression and also stimulated DRA promoter activity, suggesting transcriptional regulation. Electrophoretic mobility shift and chromatin immunoprecipitation assays demonstrated direct binding of CDX2 to one of the two putative CDX2 binding sites in the DRA promoter (+645/+663). In summary, our studies, for the first time, demonstrate transcriptional regulation of DRA expression by CDX2, implying that reduced expression of DRA in inflammatory bowel disease-associated diarrhea may, in part, be due to downregulation of CDX2 in the inflamed mucosa.NEW & NOTEWORTHY SLC26A3 [downregulated in adenoma (DRA)] mediates intestinal luminal NaCl absorption and is downregulated in inflammatory bowel disease-associated diarrhea. Since both DRA and caudal-type homeobox protein-2 (CDX2) are reduced in intestinal inflammation and the DRA promoter harbors CDX2 binding sites, we examined whether the DRA gene is regulated by CDX2. Our studies, for the first time, demonstrate transcriptional regulation of DRA expression by CDX2 via direct binding to the DRA promoter, suggesting that reduced expression of DRA in inflammatory bowel disease-associated diarrhea could, in part, be attributed to downregulation of CDX2.
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Affiliation(s)
- Ishita Chatterjee
- 2Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois;
| | - Anoop Kumar
- 2Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois;
| | | | | | - Ravinder K. Gill
- 2Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois;
| | - Waddah A. Alrefai
- 1Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois; ,2Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois;
| | - Alip Borthakur
- 2Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois;
| | - Michael Verzi
- 4Department of Genetics, Rutgers University, Piscataway, New Jersey
| | - Pradeep K. Dudeja
- 1Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois; ,2Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois;
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Lacruz RS, Habelitz S, Wright JT, Paine ML. DENTAL ENAMEL FORMATION AND IMPLICATIONS FOR ORAL HEALTH AND DISEASE. Physiol Rev 2017; 97:939-993. [PMID: 28468833 DOI: 10.1152/physrev.00030.2016] [Citation(s) in RCA: 223] [Impact Index Per Article: 31.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 01/10/2017] [Accepted: 01/10/2017] [Indexed: 12/16/2022] Open
Abstract
Dental enamel is the hardest and most mineralized tissue in extinct and extant vertebrate species and provides maximum durability that allows teeth to function as weapons and/or tools as well as for food processing. Enamel development and mineralization is an intricate process tightly regulated by cells of the enamel organ called ameloblasts. These heavily polarized cells form a monolayer around the developing enamel tissue and move as a single forming front in specified directions as they lay down a proteinaceous matrix that serves as a template for crystal growth. Ameloblasts maintain intercellular connections creating a semi-permeable barrier that at one end (basal/proximal) receives nutrients and ions from blood vessels, and at the opposite end (secretory/apical/distal) forms extracellular crystals within specified pH conditions. In this unique environment, ameloblasts orchestrate crystal growth via multiple cellular activities including modulating the transport of minerals and ions, pH regulation, proteolysis, and endocytosis. In many vertebrates, the bulk of the enamel tissue volume is first formed and subsequently mineralized by these same cells as they retransform their morphology and function. Cell death by apoptosis and regression are the fates of many ameloblasts following enamel maturation, and what cells remain of the enamel organ are shed during tooth eruption, or are incorporated into the tooth's epithelial attachment to the oral gingiva. In this review, we examine key aspects of dental enamel formation, from its developmental genesis to the ever-increasing wealth of data on the mechanisms mediating ionic transport, as well as the clinical outcomes resulting from abnormal ameloblast function.
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Affiliation(s)
- Rodrigo S Lacruz
- Department of Basic Science and Craniofacial Biology, College of Dentistry, New York University, New York, New York; Department of Preventive and Restorative Dental Sciences, University of California, San Francisco, San Francisco, California; Department of Pediatric Dentistry, School of Dentistry, University of North Carolina, Chapel Hill, North Carolina; Herman Ostrow School of Dentistry, Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, California
| | - Stefan Habelitz
- Department of Basic Science and Craniofacial Biology, College of Dentistry, New York University, New York, New York; Department of Preventive and Restorative Dental Sciences, University of California, San Francisco, San Francisco, California; Department of Pediatric Dentistry, School of Dentistry, University of North Carolina, Chapel Hill, North Carolina; Herman Ostrow School of Dentistry, Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, California
| | - J Timothy Wright
- Department of Basic Science and Craniofacial Biology, College of Dentistry, New York University, New York, New York; Department of Preventive and Restorative Dental Sciences, University of California, San Francisco, San Francisco, California; Department of Pediatric Dentistry, School of Dentistry, University of North Carolina, Chapel Hill, North Carolina; Herman Ostrow School of Dentistry, Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, California
| | - Michael L Paine
- Department of Basic Science and Craniofacial Biology, College of Dentistry, New York University, New York, New York; Department of Preventive and Restorative Dental Sciences, University of California, San Francisco, San Francisco, California; Department of Pediatric Dentistry, School of Dentistry, University of North Carolina, Chapel Hill, North Carolina; Herman Ostrow School of Dentistry, Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, California
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Abstract
OBJECTIVES We aimed to improve the knowledge of pathogenic mutations in sporadic cases of congenital chloride diarrhea (CCD) and emphasize the importance of functional studies to define the effect of novel mutations. METHODS All member 3 of solute carrier family 26 (SLC26A3) coding regions were sequenced in 17 sporadic patients with CCD. Moreover, the minigene system was used to analyze the effect of 2 novel splicing mutations. RESULTS We defined the SLC26A3 genotype of all 17 patients with CCD and identified 12 novel mutations. Using the minigene system, we confirmed the in silico prediction of a complete disruption of splicing pattern caused by 2 of these novel mutations: the c.971+3_971+4delAA and c.735+4_c.735+7delAGTA. Moreover, several prediction tools and a structure-function prediction defined the pathogenic role of 6 novel missense mutations. CONCLUSIONS We confirm the molecular heterogeneity of sporadic CCD adding 12 novel mutations to the list of known pathogenic mutations. Moreover, we underline the importance, for laboratories that offer molecular diagnosis and genetic counseling, to perform fast functional analysis of novel mutations.
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Pathogen-induced secretory diarrhea and its prevention. Eur J Clin Microbiol Infect Dis 2016; 35:1721-1739. [DOI: 10.1007/s10096-016-2726-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 07/05/2016] [Indexed: 12/19/2022]
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Kravtsov DV, Ahsan MK, Kumari V, van Ijzendoorn SCD, Reyes-Mugica M, Kumar A, Gujral T, Dudeja PK, Ameen NA. Identification of intestinal ion transport defects in microvillus inclusion disease. Am J Physiol Gastrointest Liver Physiol 2016; 311:G142-55. [PMID: 27229121 PMCID: PMC4967175 DOI: 10.1152/ajpgi.00041.2016] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 05/08/2016] [Indexed: 01/31/2023]
Abstract
Loss of function mutations in the actin motor myosin Vb (Myo5b) lead to microvillus inclusion disease (MVID) and death in newborns and children. MVID results in secretory diarrhea, brush border (BB) defects, villus atrophy, and microvillus inclusions (MVIs) in enterocytes. How loss of Myo5b results in increased stool loss of chloride (Cl(-)) and sodium (Na(+)) is unknown. The present study used Myo5b loss-of-function human MVID intestine, polarized intestinal cell models of secretory crypt (T84) and villus resembling (CaCo2BBe, C2BBe) enterocytes lacking Myo5b in conjunction with immunofluorescence confocal stimulated emission depletion (gSTED) imaging, immunohistochemical staining, transmission electron microscopy, shRNA silencing, immunoblots, and electrophysiological approaches to examine the distribution, expression, and function of the major BB ion transporters NHE3 (Na(+)), CFTR (Cl(-)), and SLC26A3 (DRA) (Cl(-)/HCO3 (-)) that control intestinal fluid transport. We hypothesized that enterocyte maturation defects lead villus atrophy with immature secretory cryptlike enterocytes in the MVID epithelium. We investigated the role of Myo5b in enterocyte maturation. NHE3 and DRA localization and function were markedly reduced on the BB membrane of human MVID enterocytes and Myo5bKD C2BBe cells, while CFTR localization was preserved. Forskolin-stimulated CFTR ion transport in Myo5bKD T84 cells resembled that of control. Loss of Myo5b led to YAP1 nuclear retention, retarded enterocyte maturation, and a cryptlike phenotype. We conclude that preservation of functional CFTR in immature enterocytes, reduced functional expression of NHE3, and DRA contribute to Cl(-) and Na(+) stool loss in MVID diarrhea.
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Affiliation(s)
- Dmitri V. Kravtsov
- 1Department of Pediatrics/Gastroenterology and Hepatology, Yale School of Medicine, New Haven, Connecticut;
| | - Md Kaimul Ahsan
- 1Department of Pediatrics/Gastroenterology and Hepatology, Yale School of Medicine, New Haven, Connecticut;
| | - Vandana Kumari
- 1Department of Pediatrics/Gastroenterology and Hepatology, Yale School of Medicine, New Haven, Connecticut;
| | - Sven C. D. van Ijzendoorn
- 2Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands;
| | | | - Anoop Kumar
- 4Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois and Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois; and
| | - Tarunmeet Gujral
- 4Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois and Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois; and
| | - Pradeep K. Dudeja
- 4Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois and Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois; and
| | - Nadia A. Ameen
- 1Department of Pediatrics/Gastroenterology and Hepatology, Yale School of Medicine, New Haven, Connecticut; ,5Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, Connecticut
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Asghar MN, Priyamvada S, Nyström JH, Anbazhagan AN, Dudeja PK, Toivola DM. Keratin 8 knockdown leads to loss of the chloride transporter DRA in the colon. Am J Physiol Gastrointest Liver Physiol 2016; 310:G1147-54. [PMID: 27125276 PMCID: PMC4935477 DOI: 10.1152/ajpgi.00354.2015] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 04/23/2016] [Indexed: 02/06/2023]
Abstract
Keratins (K) are intermediate filament proteins important in protection from stress. The roles of keratins in the intestine are not clear, but K8 knockout (K8(-/-)) mice develop a Th2-type colonic inflammation, epithelial hyperproliferation, and mild diarrhea caused by a keratin level-dependent decrease in short-circuit current and net sodium and chloride absorption in the distal colon. The lack of K8 leads to mistargeting or altered levels of membrane proteins in colonocytes; however, the main transporter responsible for the keratin-related ion transport defect is unknown. We here analyzed protein and mRNA levels of candidate ion transporters CFTR, PAT-1, NHE-3, and DRA in ileum, cecum, and proximal and distal colon. Although no differences were observed for CFTR, PAT-1, or NHE-3, DRA mRNA levels were decreased by three- to fourfold and DRA protein was almost entirely lost in K8(-/-) cecum and proximal and distal colon compared with K8(+/+), whereas the levels in ileum were normal. In K8(+/-) mice, DRA mRNA levels were unaltered, while decreased DRA protein levels were detected in the proximal colon. Immunofluorescence staining confirmed the loss of DRA in K8(-/-) distal colon, while K8(+/-) displayed a similar but more patchy apical DRA distribution compared with K8(+/+) DRA was similarly decreased when K8 was knocked down in Caco-2 cells, confirming that K8 levels modulate DRA levels in an inflammation-independent manner. Taken together, the loss of DRA in the K8(-/-) mouse colon and cecum explains the dramatic chloride transport defect and diarrheal phenotype after K8 inactivation and identifies K8 as a novel regulator of DRA.
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Affiliation(s)
- M. Nadeem Asghar
- 1Cell Biology, Biosciences, Faculty of Science and Engineering, Åbo Akademi University and Turku Center for Disease Modeling, University of Turku, Turku, Finland; and
| | - Shubha Priyamvada
- 2University of Illinois at Chicago, Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
| | - Joel H. Nyström
- 1Cell Biology, Biosciences, Faculty of Science and Engineering, Åbo Akademi University and Turku Center for Disease Modeling, University of Turku, Turku, Finland; and
| | | | - Pradeep K. Dudeja
- 2University of Illinois at Chicago, Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
| | - Diana M. Toivola
- 1Cell Biology, Biosciences, Faculty of Science and Engineering, Åbo Akademi University and Turku Center for Disease Modeling, University of Turku, Turku, Finland; and
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Anbazhagan AN, Priyamvada S, Alakkam A, Kumar A, Borthakur A, Saksena S, Gill RK, Alrefai WA, Dudeja PK. Transcriptional modulation of SLC26A3 (DRA) by sphingosine-1-phosphate. Am J Physiol Gastrointest Liver Physiol 2016; 310:G1028-35. [PMID: 27079615 PMCID: PMC4935485 DOI: 10.1152/ajpgi.00308.2015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 04/12/2016] [Indexed: 01/31/2023]
Abstract
SLC26A3 or Downregulated in adenoma (DRA) is the major Cl(-)/HCO3 (-) exchanger involved in electroneutral NaCl absorption in the mammalian intestine. Alterations in DRA function and expression have been implicated in diarrheal diseases associated with inflammation or infection. Therefore, agents that upregulate DRA activity may serve as potential antidiarrheals. In this regard, sphingosine-1-phosphate (S1P), a member of the bioactive sphingolipid family, has been shown to modulate various cellular processes including improvement of intestinal barrier function. However, the role of S1P in modulating intestinal chloride absorption by regulating DRA is not known. Therefore, the present studies were designed to examine the direct effects of S1P on apical Cl(-)/HCO3 (-) exchange activity and DRA expression. S1P significantly increased Cl(-)/HCO3 (-) exchange activity and also significantly increased DRA mRNA and protein expression. Increased DRA mRNA by S1P was accompanied by enhanced DRA promoter activity, indicating involvement of transcriptional mechanisms. The specific S1P receptor subtype-2 (S1PR2) antagonist JTE-013 blocked the stimulatory effects of S1P on DRA promoter activity, indicating the involvement of S1PR2 S1P-mediated increase in DRA promoter activity involved PI3K/Akt pathway. Progressive deletions of the DRA promoter indicated that the putative S1P-responsive elements are present in the -790/-398 region of the DRA promoter. Furthermore, results obtained from electrophoretic mobility shift assay showed that S1P stimulated DRA promoter activity via increased binding of Ying-Yang1 (YY1) in the S1P-responsive region. In conclusion, transcriptional modulation of DRA expression and function in response to S1P through a PI3/Akt pathway represents a novel role of S1P as a potential proabsorptive agent.
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Affiliation(s)
- Arivarasu N. Anbazhagan
- 2Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Shubha Priyamvada
- 2Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Anas Alakkam
- 2Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Anoop Kumar
- 2Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Alip Borthakur
- 2Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Seema Saksena
- 1Jesse Brown VA Medical Center, Research Service, Chicago, Illinois; and ,2Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Ravinder K. Gill
- 2Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Waddah A. Alrefai
- 1Jesse Brown VA Medical Center, Research Service, Chicago, Illinois; and ,2Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Pradeep K. Dudeja
- 1Jesse Brown VA Medical Center, Research Service, Chicago, Illinois; and ,2Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
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Lu X, Sun D, Xu B, Pan J, Wei Y, Mao X, Yu D, Liu H, Gao B. In Silico Screening and Molecular Dynamic Study of Nonsynonymous Single Nucleotide Polymorphisms Associated with Kidney Stones in the SLC26A6 Gene. J Urol 2016; 196:118-23. [PMID: 26812303 DOI: 10.1016/j.juro.2016.01.093] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/14/2016] [Indexed: 10/22/2022]
Abstract
PURPOSE SLC26A6 is a multifunctional anion transporter with a critical physiological role in the transport of oxalate anions. Recognizing a genetic variant of SLC26A6 would advance our understanding of oxalate transport in the formation of calcium oxalate stones. MATERIALS AND METHODS All nsSNPs (nonsynonymous single nucleotide polymorphisms) reported in human SLC26A6 were investigated using 4 in silico tools, including SIFT (Sorting Intolerant From Tolerant), PROVEAN (Protein Variation Effect Analyzer), PhD-SNP (Predictor of human Deleterious Single Nucleotide Polymorphisms) and MutPred. A total of 426 subjects, including 225 with kidney stones and 201 healthy controls, were included in study to genotype the candidate disease associated nsSNP using allele specific polymerase chain reaction. Furthermore, the structural consequences due to the mutation were assessed using homology modeling and molecular dynamics simulation methods. RESULTS The nsSNP rs184187143 was identified as a more probable disease associated variant in the SLC26A6 gene by in silico screening. The C allele carrier showed a 6.1-fold increased kidney stone risk compared with G allele carriers in the nsSNP (OR 6.1, 95% CI 1.36-27.38, p = 0.007). We found that the mutation from arginine to glycine leads to the loss of 2 hydrogen bonds and to an unstable structure in the STAS domain of SLC26A6. CONCLUSIONS Our results indicate that the variant G539R in the SLC26A6 gene is associated with kidney stone risk, providing a clear clue to further achieve insight into oxalate transport in kidney stone formation.
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Affiliation(s)
- Xiuli Lu
- Department of Biochemistry and Cell Biology, School of Life Science, Liaoning University, Shenyang, People's Republic of China; Research Center for Computer Simulating and Information Processing of Bio-macromolecules of Liaoning Province, Shenyang, People's Republic of China
| | - Deliang Sun
- Department of Biochemistry and Cell Biology, School of Life Science, Liaoning University, Shenyang, People's Republic of China
| | - Bo Xu
- Department of Biochemistry and Cell Biology, School of Life Science, Liaoning University, Shenyang, People's Republic of China
| | - Jichuan Pan
- Department of Cell Biology and Genetics, Shenyang Medical College, Shenyang, People's Republic of China
| | - Yanhong Wei
- Department of Cell Biology and Genetics, Shenyang Medical College, Shenyang, People's Republic of China
| | - Xu Mao
- Department of Cell Biology and Genetics, Shenyang Medical College, Shenyang, People's Republic of China
| | - Daojun Yu
- Department of Cell Biology and Genetics, Shenyang Medical College, Shenyang, People's Republic of China
| | - Hongsheng Liu
- Research Center for Computer Simulating and Information Processing of Bio-macromolecules of Liaoning Province, Shenyang, People's Republic of China
| | - Bing Gao
- Department of Cell Biology and Genetics, Shenyang Medical College, Shenyang, People's Republic of China; Key Laboratory of Environment and Population Health of Liaoning Education Ministry, Shenyang Medical College, Shenyang, People's Republic of China; China-Japan Kidney Stone Research Center, Shenyang, People's Republic of China.
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Di Stadio CS, Altieri F, Miselli G, Elce A, Severino V, Chambery A, Quagliariello V, Villano V, de Dominicis G, Rippa E, Arcari P. AMP18 interacts with the anion exchanger SLC26A3 and enhances its expression in gastric cancer cells. Biochimie 2015; 121:151-60. [PMID: 26700142 DOI: 10.1016/j.biochi.2015.12.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Accepted: 12/01/2015] [Indexed: 01/05/2023]
Abstract
AMP18 is a stomach-specific secreted protein expressed in normal gastric mucosa but absent in gastric cancer. AMP18 plays a major role in maintaining gastric mucosa integrity and is characterized by the presence of a BRICHOS domain consisting of about 100 amino acids, present also in several unrelated proteins, and probably endowed with a chaperon-like activity. In this work, we exploited a functional proteomic strategy to identify potential AMP18 interactors with the aim to add knowledge on its functional role within gastric cell lines and tissues. To this purpose, recombinant biotinylated AMP18 was purified and incubated with protein extract from human normal gastric mucosa by applying an affinity chromatography strategy. The interacting proteins were identified by peptide mass fingerprinting using MALDI-TOF mass spectrometry. The pool of interacting proteins contained SLC26A3, a protein expressed in the apical membrane of intestinal epithelial cells, supposed to play a critical role in Cl(-) absorption and fluid homeostasis. The interaction was also confirmed by Western blot with anti-SLC26A3 on transfected AGS cell extract following AMP18 pull-down. Furthermore, the interaction between AMP18 and SLC26A3 was also validated by confocal microscopy that showed a co-localization of both proteins at plasma membrane level. More importantly, for the first time, we showed that SLC26A3 is down-regulated in gastric cancer and that the overexpression of AMP18 in AMP-transfected gastric cancer cells up-regulated the expression of SLC26A3 both at transcriptional and translational level, the latter probably through the activation of the MAP kinases pathway. These findings strongly suggest that AMP18 might play an anti-inflammatory role in maintaining mucosal integrity also by regulating SLC26A3 level.
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Affiliation(s)
- Chiara Stella Di Stadio
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy
| | - Filomena Altieri
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy
| | - Giuseppina Miselli
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy
| | - Ausilia Elce
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy
| | - Valeria Severino
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, Second University of Naples, Caserta, Italy
| | - Angela Chambery
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, Second University of Naples, Caserta, Italy; IRCCS Multimedica, Milan, Italy
| | - Vincenzo Quagliariello
- Laboratory of Biotechnology, Department of Anesthesia, Surgical and Emergency Sciences, Second University of Naples, Via Costantinopoli 16, I-80138, Naples, Italy
| | - Valentina Villano
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy
| | | | - Emilia Rippa
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy.
| | - Paolo Arcari
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy; CEINGE, Advanced Biotechnology Scarl, Via Gaetano Salvatore 486, I-80145, Naples, Italy.
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Effect of SLC26 anion transporter disease-causing mutations on the stability of the homologous STAS domain of E. coli DauA (YchM). Biochem J 2015; 473:615-26. [PMID: 26635355 DOI: 10.1042/bj20151025] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 12/03/2015] [Indexed: 01/08/2023]
Abstract
The human solute carrier 26 (SLC26) family of anion transporters consists of ten members that are found in various organs in the body including the stomach, intestine, kidney, thyroid and ear where they transport anions including bicarbonate, chloride and sulfate, typically in an exchange mode. Mutations in these genes cause a plethora of diseases such as diastrophic dysplasia affecting sulfate uptake into chondrocytes (SLC26A2), congenital chloride-losing diarrhoea (SLC26A3) affecting chloride secretion in the intestine and Pendred's syndrome (SLC26A4) resulting in hearing loss. To understand how these mutations affect the structures of the SLC26 membrane proteins and their ability to function properly, 12 human disease-causing mutants from SLC26A2, SLC26A3 and SLC26A4 were introduced into the equivalent sites of the sulfate transporter anti-sigma factor antagonist (STAS) domain of a bacterial homologue SLC26 protein DauA (YchM). Biophysical analyses including size-exclusion chromatography, circular dichroism (CD), differential scanning fluorimetry (DSF) and tryptophan fluorescence revealed that most mutations caused protein instability and aggregation. The mutation A463K, equivalent to N558K in human SLC26A4, which is located within α-helix 1 of the DauA STAS domain, stabilized the protein. CD measurements showed that most disease-related mutants had a mildly reduced helix content, but were more sensitive to thermal denaturation. Fluorescence spectroscopy showed that the mutants had more open structures and were more readily denatured by urea, whereas DSF indicated more labile folds. Overall, we conclude that the disease-associated mutations destabilized the STAS domain resulting in an increased propensity to misfold and aggregate.
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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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Bile acids inhibit Na⁺/H⁺ exchanger and Cl⁻/HCO₃⁻ exchanger activities via cellular energy breakdown and Ca²⁺ overload in human colonic crypts. Pflugers Arch 2015; 467:1277-90. [PMID: 25015415 DOI: 10.1007/s00424-014-1560-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Accepted: 06/17/2014] [Indexed: 12/17/2022]
Abstract
Bile acids play important physiological role in the solubilisation and absorption of dietary lipids. However, under pathophysiological conditions, such as short bowel syndrome, they can reach the colon in high concentrations inducing diarrhoea. In this study, our aim was to characterise the cellular pathomechanism of bile-induced diarrhoea using human samples. Colonic crypts were isolated from biopsies of patients (controls with negative colonoscopic findings) and of cholecystectomised/ileum-resected patients with or without diarrhoea. In vitro measurement of the transporter activities revealed impaired Na⁺/H⁺ exchanger (NHE) and Cl⁻/HCO₃⁻ exchanger (CBE) activities in cholecystectomised/ileum-resected patients suffering from diarrhoea, compared to control patients. Acute treatment of colonic crypts with 0.3 mM chenodeoxycholate caused dose-dependent intracellular acidosis; moreover, the activities of acid/base transporters (NHE and CBE) were strongly impaired. This concentration of chenodeoxycholate did not cause morphological changes in colonic epithelial cells, although significantly reduced the intracellular ATP level, decreased mitochondrial transmembrane potential and caused sustained intracellular Ca²⁺ elevation. We also showed that chenodeoxycholate induced Ca²⁺ release from the endoplasmic reticulum and extracellular Ca²⁺ influx contributing to the Ca²⁺ elevation. Importantly, our results suggest that the chenodeoxycholate-induced inhibition of NHE activities was ATP-dependent, whereas the inhibition of CBE activity was mediated by the sustained Ca²⁺ elevation. We suggest that bile acids inhibit the function of ion transporters via cellular energy breakdown and Ca²⁺ overload in human colonic epithelial cells, which can reduce fluid and electrolyte absorption in the colon and promote the development of diarrhea.
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Priyamvada S, Anbazhagan AN, Gujral T, Borthakur A, Saksena S, Gill RK, Alrefai WA, Dudeja PK. All-trans-retinoic Acid Increases SLC26A3 DRA (Down-regulated in Adenoma) Expression in Intestinal Epithelial Cells via HNF-1β. J Biol Chem 2015; 290:15066-77. [PMID: 25887398 PMCID: PMC4463450 DOI: 10.1074/jbc.m114.566356] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Revised: 04/10/2015] [Indexed: 11/06/2022] Open
Abstract
All-trans-retinoic acid (ATRA) is an active vitamin A derivative known to modulate a number of physiological processes, including growth and development, differentiation, and gene transcription. The protective effect of ATRA in gut inflammation and diarrheal diseases has been documented. In this regard, down-regulated in adenoma (DRA, a key luminal membrane Cl(-) transporter involved in NaCl absorption) has been shown to be suppressed in intestinal inflammation. This suppression of DRA is associated with diarrheal phenotype. Therefore, current studies were undertaken to examine the effects of ATRA on DRA expression. DRA mRNA levels were significantly elevated (∼4-fold) in response to ATRA with induction starting as early as 8 h of incubation. Similarly, ATRA increased DRA protein expression by ∼50%. Furthermore, DRA promoter activity was significantly increased in response to ATRA indicating transcriptional activation. ATRA effects on DRA expression appeared to be mediated via the RAR-β receptor subtype, as ATRA remarkably induced RAR-β mRNA levels, whereas RAR-β knockdown substantially attenuated the ability of ATRA to increase DRA expression. Results obtained from agonist (CH-55) and antagonist (LE-135) studies further confirmed that ATRA exerts its effects through RAR-β. Furthermore, ATRA treatment resulted in a significant increase in HNF-1β mRNA levels. The ability of ATRA to induce DRA expression was inhibited in the presence of HNF-1β siRNA indicative of its involvement in ATRA-induced effects on DRA expression. In conclusion, ATRA may act as an antidiarrheal agent by increasing DRA expression via the RAR-β/HNF-1β-dependent pathway.
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Affiliation(s)
- Shubha Priyamvada
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612
| | - Arivarasu N Anbazhagan
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612
| | - Tarunmeet Gujral
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612
| | - Alip Borthakur
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612
| | - Seema Saksena
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612
| | - Ravinder K Gill
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612
| | - Waddah A Alrefai
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612 From the Jesse Brown Veterans Affairs Medical Center
| | - Pradeep K Dudeja
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612 From the Jesse Brown Veterans Affairs Medical Center,
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Abou Ziki MD, Verjee MA. Rare mutation in the SLC26A3 transporter causes life-long diarrhoea with metabolic alkalosis. BMJ Case Rep 2015; 2015:bcr-2014-206849. [PMID: 25568271 DOI: 10.1136/bcr-2014-206849] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
SLC26A3, a chloride/bicarbonate transporter mainly expressed in the intestines, plays a pivotal role in chloride absorption. We present a 23-year-old woman with a history of congenital chloride diarrhoea (CCD) and renal transplant who was admitted for rehydration and treatment of acute kidney injury after she presented with an acute diarrhoeal episode. Laboratory investigations confirmed metabolic alkalosis and severe hypochloraemia, consistent with her underlying CCD. This contrasts with most other forms of diarrhoea, which are normally associated with metabolic acidosis. Genetic testing was offered and revealed a homozygous non-sense mutation in SLC26A3 (Gly-187-Stop). This loss-of-function mutation results in bicarbonate retention in the blood and chloride loss into the intestinal lumen. Symptomatic management with daily NaCl and KCl oral syrups was supplemented with omeprazole therapy. The loss of her own kidneys is most likely due to crystal-induced nephropathy secondary to chronic volume contraction and chloride depletion. This case summarises the pathophysiology and management of CCD.
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Affiliation(s)
- Maen D Abou Ziki
- Yale Waterbury Internal Medicine Residency Program, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Mohamud A Verjee
- Department of Medical Education, Weill Cornell Medical College in Qatar, Doha, Qatar
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Kumar A, Hecht C, Priyamvada S, Anbazhagan AN, Alakkam A, Borthakur A, Alrefai WA, Gill RK, Dudeja PK. Probiotic Bifidobacterium species stimulate human SLC26A3 gene function and expression in intestinal epithelial cells. Am J Physiol Cell Physiol 2014; 307:C1084-92. [PMID: 25143346 DOI: 10.1152/ajpcell.00194.2014] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
SLC26A3, or downregulated in adenoma (DRA), plays a major role in mediating Cl(-) absorption in the mammalian intestine. Disturbances in DRA function and expression have been implicated in intestinal disorders such as congenital Cl(-) diarrhea and gut inflammation. We previously showed that an increase in DRA function and expression by Lactobacillus acidophilus and its culture supernatant (CS) might underlie antidiarrheal effects of this probiotic strain. However, the effects of Bifidobacterium species, important inhabitants of the human colon, on intestinal Cl(-)/HCO3 (-) exchange activity are not known. Our current results demonstrate that CS derived from Bifidobacterium breve, Bifidobacterium infantis, and Bifidobacterium bifidum increased anion exchange activity in Caco-2 cells (∼1.8- to 2.4-fold). Consistent with the increase in DRA function, CS also increased the protein, as well as the mRNA, level of DRA (but not putative anion transporter 1). CS of all three Bifidobacterium sp. increased DRA promoter activity (-1,183/+114 bp) in Caco-2 cells (1.5- to 1.8-fold). Furthermore, the increase in DRA mRNA expression by CS of B. breve and B. infantis was blocked in the presence of the transcription inhibitor actinomycin D (5 μM) and the ERK1/2 MAPK pathway inhibitor U0126 (10 μM). Administration of live B. breve, B. infantis, and B. bifidum by oral gavage to mice for 24 h increased DRA mRNA and protein levels in the colon. These data demonstrate an upregulation of DRA via activation of the ERK1/2 pathway that may underlie potential antidiarrheal effects of Bifidobacterium sp.
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Affiliation(s)
- Anoop Kumar
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois; Singhania University Pacheri Bari, Rajasthan, India
| | - Cameron Hecht
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Shubha Priyamvada
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Arivarasu N Anbazhagan
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Anas Alakkam
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Alip Borthakur
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Waddah A Alrefai
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois; Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois; and
| | - Ravinder K Gill
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Pradeep K Dudeja
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois; Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois; and
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Li J, Xia F, Reithmeier RAF. N-glycosylation and topology of the human SLC26 family of anion transport membrane proteins. Am J Physiol Cell Physiol 2014; 306:C943-60. [PMID: 24647542 DOI: 10.1152/ajpcell.00030.2014] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The human solute carrier (SLC26) family of anion transporters consists of 10 members (SLCA1-11, SLCA10 being a pseudogene) that encode membrane proteins containing ~12 transmembrane (TM) segments with putative N-glycosylation sites (-NXS/T-) in extracellular loops and a COOH-terminal cytosolic STAS domain. All 10 members of the human SLC26 family, FLAG-tagged at the NH2 terminus, were transiently expressed in HEK-293 cells. While most proteins were observed to contain both high-mannose and complex oligosaccharides, SLC26A2 was mainly in the complex form, SLC26A4 in the high-mannose form, and SLC26A8 was not N-glycosylated. Mutation of the putative N-glycosylation sites showed that most members contain multiple N-glycosylation sites in the second extracytosolic (EC) loop, except SLC26A11, which was N-glycosylated in EC loop 4. Immunofluorescence staining of permeabilized cells localized the proteins to the plasma membrane and the endoplasmic reticulum, with SLC26A2 highly localized to the plasma membrane. N-glycosylation was not a necessary requirement for cell surface expression as the localization of nonglycosylated proteins was similar to their wild-type counterparts, although a lower level of cell-surface biotinylation was observed. No immunostaining of intact cells was observed for any SLC26 members, demonstrating that the NH2-terminal FLAG tag was located in the cytosol. Topological models of the SLC26 proteins that contain an even number of transmembrane segments with both the NH2 and COOH termini located in the cytosol and utilized N-glycosylation sites defining the positions of two EC loops are presented.
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Affiliation(s)
- Jing Li
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Fan Xia
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
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Cordat E, Reithmeier RA. Structure, Function, and Trafficking of SLC4 and SLC26 Anion Transporters. CURRENT TOPICS IN MEMBRANES 2014; 73:1-67. [DOI: 10.1016/b978-0-12-800223-0.00001-3] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Seo KA, Lee NM, Kim GJ, Yun SW, Chae SA, Lim IS, Choi ES, Yoo BH. Congenital chloride diarrhea in dizygotic twins. Pediatr Gastroenterol Hepatol Nutr 2013; 16:195-9. [PMID: 24224154 PMCID: PMC3819694 DOI: 10.5223/pghn.2013.16.3.195] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Revised: 08/13/2013] [Accepted: 08/23/2013] [Indexed: 11/18/2022] Open
Abstract
Congenital chloride diarrhea (CLD) is a rare inherited autosomal recessive disorder. Mutations of the solute carrier family 26 member 3 gene cause profuse, chloride ion rich diarrhea, which results in hypochloremia, hyponatremia and metabolic alkalosis with dehydration. If a fetal ultrasound shows bowel dilatation suggestive of bowel obstruction, or if a neonate shows persistent diarrhea and metabolic alkalosis, CLD should be considered in the differential diagnosis. The severity of CLD varies, but early detection and early therapy can prevent complications including growth failure. We report a case of dizygotic twins affected by CLD who had been born to non-consanguineous parents. Both of them showed growth failure, but one of the twins experienced worse clinical course. He showed developmental delay, along with dehydration and severe electrolyte imbalance. He was diagnosed with CLD first at 6-month age, and then the other one was also diagnosed with CLD.
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Affiliation(s)
- Kyung Ah Seo
- Department of Pediatrics, College of Medicine, Chung-Ang University, Seoul, Korea
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Bakouh N, Bienvenu T, Thomas A, Ehrenfeld J, Liote H, Roussel D, Duquesnoy P, Farman N, Viel M, Cherif-Zahar B, Amselem S, Taam RA, Edelman A, Planelles G, Sermet-Gaudelus I. Characterization of SLC26A9 in patients with CF-like lung disease. Hum Mutat 2013; 34:1404-14. [PMID: 24272871 DOI: 10.1002/humu.22382] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2012] [Accepted: 07/10/2013] [Indexed: 01/07/2023]
Abstract
Diffuse bronchiectasis is a common problem in respiratory clinics. We hypothesized that mutations in the solute carrier 26A9 (SLC26A9) gene, encoding for a chloride (Cl(-)) transporter mainly expressed in lungs, may lead to defects in mucociliary clearance. We describe two missense variants in the SLC26A9 gene in heterozygote patients presenting with diffuse idiopathic bronchiectasis : p.Arg575Trp, identified in a patient also heterozygote for p.Phe508del in the CFTR gene; and p.Val486Ile. Expression of both mutants in Xenopus laevis oocytes abolished SLC26A9-mediated Cl(-) conductance without decreasing protein membrane expression. Coexpression of CFTR with SLC26A9-p.Val486Ile resulted in a significant increase in the Cl(-) current induced by PKA stimulation, similar to that obtained in oocytes expressing CFTR and SLC26A9-WT. In contrast, coexpression of CFTR with SLC26A9-p.Arg575Trp inhibited SLC26A9-enhanced CFTR activation upon PKA. Further structure-function analyses led us to propose a site encompassing Arg575 in the SLC26A9-STAS domain for CFTR-SLC26A9 interaction. We hypothesize that SLC26A9-p.Arg575Trp prevented SLC26A9-mediated functional activation of CFTR by altering SLC26A9-CFTR interaction. Although we cannot confirm that these mutations by themselves are deleterious, we propose that they trigger the pathogenic role of a single CFTR mutation and provide insight into a novel mechanism of Cl(-) transport alteration across the respiratory mucosa, based on functional inhibition of CFTR.
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Affiliation(s)
- Naziha Bakouh
- INSERM U 845, Paris, France; Faculté de Médecine, Université René Descartes, Paris V, Paris, France
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Hong J, Seo JK, Ko JS, Cheong HI, Choi JH, Lee JH, Seo JW. Congenital chloride diarrhea in Korean children: novel mutations and genetic characteristics. Eur J Pediatr 2013; 172:545-50. [PMID: 23274434 DOI: 10.1007/s00431-012-1905-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2012] [Accepted: 11/28/2012] [Indexed: 11/28/2022]
Abstract
UNLABELLED Congenital chloride diarrhea (CLD, OMIM#214700) is an autosomal recessive disorder caused by mutations in the solute carrier family 26 member 3 (SLC26A3) gene, which encodes an intestinal chloride/bicarbonate exchanger. While more than 50 mutations have been identified throughout the world, there have been no data on the genetic characteristics of the patients of East Asian ethnic origin. In this study, we performed genetic analysis by direct sequencing of the 20 exons and parts of exon-intron boundaries of the SLC26A3 gene in eight patients of Korean origin with non-consanguineous parents. We identified three novel mutations, including two splice-site mutations (c.2063-1G>T in intron 18, c.1047+3 A>C in intron 12) and one missense mutation (p.Ser134Asn in exon 5). One previously identified mutation was also found (p.Pro131Leu in exon 5). The most common mutation was c.2063-1G>T, which was found in at least one allele of all patients. CONCLUSION This is the first report to demonstrate the genetic background of CLD in a single ethnic group of East Asian descent. The c.2063-1G>T mutation could be suggested as a founder mutation in Korean population so that the targeting sequencing for the mutation would be a cost-efficient screening method to confirm a diagnosis of CLD in patients of Korean descent.
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Affiliation(s)
- Jeana Hong
- Division of Pediatric Gastroenterology, Hepatology and Nutrition, Seoul National University Children's Hospital, 101 Daehak-ro, Jongno-gu, Seoul 110-169, South Korea
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