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1.
JACC Case Rep ; 4(3): 121-127, 2022 Feb 02.
Article in English | MEDLINE | ID: mdl-35199001

ABSTRACT

Acute cardiorespiratory distress following device closure of ruptured sinus of Valsava (RSOV) aneurysm can have a battery of differentials. We report a case of acute left ventricular dysfunction with aspiration that caused cardiorespiratory distress immediately following RSOV device closure. Supportive medical therapy led to complete recovery. (Level of Difficulty: Intermediate.).

2.
Monaldi Arch Chest Dis ; 91(3)2021 04 06.
Article in English | MEDLINE | ID: mdl-33840182

ABSTRACT

The coronary angiographic (CAG) findings of ST elevation myocardial infarction (STEMI) in patients of coronavirus disease 2019 (COVID-19) range from increased coronary artery thrombus burden to normal coronaries due to STEMI mimics. Here we report the case of a 45-year-old gentleman who presented with evolved inferior wall myocardial infarction with ongoing angina along with mild COVID-19. CAG showed normal epicardial coronaries except for distal right posterior descending coronary artery (RPDA) 100% occlusion on careful examination. He was treated for the myocardial infarction with medical management along with treatment of COVID-19. The importance of our case is to highlight the possibility of distal total occlusion of small coronary branches which may be missed if not carefully looked for as a normal CAG in COVID-19 patient will require only supportive therapy, while the finding of distal 100% occlusion of RPDA deemed us to prescribe optimal medical therapy as per acute myocardial infarction protocol along with treatment for COVID-19.


Subject(s)
COVID-19 , Myocardial Infarction , ST Elevation Myocardial Infarction , Coronary Angiography , Humans , Male , Middle Aged , Myocardial Infarction/diagnostic imaging , SARS-CoV-2 , ST Elevation Myocardial Infarction/diagnostic imaging
3.
J Nutr ; 146(10): 1980-1990, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27629573

ABSTRACT

BACKGROUND: Campylobacter jejuni causes diarrhea worldwide; young children are most susceptible. Binding of virulent C. jejuni to the intestinal mucosa is inhibited ex vivo by α1,2-fucosylated carbohydrate moieties, including human milk oligosaccharides (HMOSs). OBJECTIVE: The simplest α1,2-fucosylated HMOS structure, 2'-fucosyllactose (2'-FL), can be predominant at ≤5 g/L milk. Although 2'-FL inhibits C. jejuni binding ex vivo and in vivo, the effects of 2'FL on the cell invasion central to C. jejuni pathogenesis have not been tested. Clinical isolates of C. jejuni infect humans, birds, and ferrets, limiting studies on its mammalian pathobiology. METHODS: Human epithelial cells HEp-2 and HT-29 infected with the virulent C. jejuni strain 81-176 human isolate were treated with 5 g 2'-FL/L, and the degree of infection and inflammatory response was measured. Four-week-old male wild-type C57BL/6 mice were fed antibiotics to reduce their intestinal microbiota and were inoculated with C. jejuni strain 81-176. The sensitivity of the resulting acute transient enteric infection and immune response to inhibition by 2'-FL ingestion was tested. RESULTS: In HEp-2 and HT-29 cells, 2'-FL attenuated 80% of C. jejuni invasion (P < 0.05) and suppressed the release of mucosal proinflammatory signals of interleukin (IL) 8 by 60-70%, IL-1ß by 80-90%, and the neutrophil chemoattractant macrophage inflammatory protein 2 (MIP-2) by 50% (P < 0.05). Ingestion of 2'-FL by mice reduced C. jejuni colonization by 80%, weight loss by 5%, histologic features of intestinal inflammation by 50-70%, and induction of inflammatory signaling molecules of the acute-phase mucosal immune response by 50-60% (P < 0.05). This acute model did not induce IL-17 (adaptive T cell response), a chronic response. CONCLUSIONS: In human cells in vitro (HEp-2, HT-29) and in a mouse infection model that recapitulated key pathologic features of C. jejuni clinical disease, 2'-FL inhibited pathogenesis and its sequelae. These data strongly support the hypothesis that 2'-FL represents a new class of oral agent for prevention, and potentially for treatment, of specific enteric infectious diseases.


Subject(s)
Campylobacter Infections/prevention & control , Campylobacter jejuni/pathogenicity , Epithelial Cells/cytology , Intestinal Mucosa/microbiology , Milk, Human/chemistry , Trisaccharides/administration & dosage , Animals , Cell Line, Tumor , Chemokine CXCL2/metabolism , Disease Models, Animal , Epithelial Cells/metabolism , Epithelial Cells/microbiology , Gastrointestinal Microbiome , HT29 Cells , Humans , Inflammation/microbiology , Inflammation/prevention & control , Interleukin-1beta/metabolism , Interleukin-8/metabolism , Intestinal Mucosa/metabolism , Male , Mice , Mice, Inbred C57BL , RNA, Messenger/metabolism , Tumor Necrosis Factor-alpha/metabolism
4.
J Nutr ; 146(2): 358-67, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26701795

ABSTRACT

BACKGROUND: The immature intestinal mucosa responds excessively to inflammatory insult, but human milk protects infants from intestinal inflammation. The ability of galactosyllactoses [galactosyloligosaccharides (GOS)], newly found in human milk oligosaccharides (HMOS), to suppress inflammation was not known. OBJECTIVE: The objective was to test whether GOS can directly attenuate inflammation and to explore the components of immune signaling modulated by GOS. METHODS: Galactosyllactose composition was measured in sequential human milk samples from days 1 through 21 of lactation and in random colostrum samples from 38 mothers. Immature [human normal fetal intestinal epithelial cell (H4)] and mature [human metastatic colonic epithelial cell (T84) and human normal colon mucosal epithelial cell (NCM-460)] enterocyte cell lines were treated with the pro-inflammatory molecules tumor necrosis factor-α (TNF-α) or interleukin-1ß (IL-1ß) or infected with Salmonella or Listeria. The inflammatory response was measured as induction of IL-8, monocyte chemoattractant protein 1 (MCP-1), or macrophage inflammatory protein-3α (MIP-3α) protein by ELISA and mRNA by quantitative reverse transcriptase-polymerase chain reaction. The ability of HMOS or synthetic GOS to attenuate this inflammation was tested in vitro and in immature human intestinal tissue ex vivo. RESULTS: The 3 galactosyllactoses (3'-GL, 4-GL, and 6'-GL) expressed in colostrum rapidly declined over early lactation (P < 0.05). In H4 cells, HMOS attenuated TNF-α- and IL-1ß-induced expression of IL-8, MIP-3α, and MCP-1 to 48-51% and pathogen-induced IL-8 and MCP-1 to 26-30% of positive controls (P < 0.001). GOS reduced TNF-α- and IL-1ß-induced inflammatory responses to 25-26% and pathogen-induced IL-8 and MCP-1 to 36-39% of positive controls (P < 0.001). GOS and HMOS mitigated nuclear translocation of nuclear transcription factor κB (NF-κB) p65. HMOS quenched the inflammatory response to Salmonella infection by immature human intestinal tissue ex vivo to 26% and by GOS to 50% of infected controls (P < 0.01). CONCLUSION: Galactosyllactose attenuated NF-κB inflammatory signaling in human intestinal epithelial cells and in human immature intestine. Thus, galactosyllactoses are strong physiologic anti-inflammatory agents in human colostrum and early milk, contributing to innate immune modulation. The potential clinical utility of galactosyllactose warrants investigation.


Subject(s)
Anti-Inflammatory Agents/therapeutic use , Cytokines/metabolism , Inflammation Mediators/metabolism , Inflammation/prevention & control , Intestinal Mucosa/drug effects , Milk, Human/chemistry , Oligosaccharides/therapeutic use , Animals , Anti-Inflammatory Agents/analysis , Anti-Inflammatory Agents/pharmacology , Cell Line , Colon/drug effects , Colon/metabolism , Colon/pathology , Colostrum/chemistry , Female , Humans , Inflammation/immunology , Inflammation/metabolism , Intestinal Mucosa/metabolism , Intestinal Mucosa/pathology , Lactation , Lactose/analysis , Lactose/pharmacology , Lactose/therapeutic use , Listeria , Mice , Oligosaccharides/chemical synthesis , Oligosaccharides/pharmacology , Pregnancy , Salmonella , Salmonella Infections/immunology , Salmonella Infections/microbiology , Salmonella Infections/pathology , Signal Transduction , Trisaccharides/analysis , Trisaccharides/pharmacology , Trisaccharides/therapeutic use
5.
J Clin Diagn Res ; 9(12): ZC43-6, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26816991

ABSTRACT

INTRODUCTION: Compromised alveolar ridge in vertical and horizontal dimension is a common finding in patients visiting practitioners for dental prosthesis. Various treatment modalities are available for correction of deficient ridges among which alveolar distraction osteogenesis is one. AIM: To study the efficacy of alveolar distraction osteogenesis in augmentation of alveolar ridges deficient in vertical dimension. MATERIALS AND METHODS: Ten patients aged 16 to 46 years with deficient alveolar ridge underwent ridge augmentation in 11 alveolar segments using the distraction osteogenesis method. For each patient a custom made distraction device was fabricated. The device was indigenously manufactured with SS-316 (ISO 3506). RESULTS: The vertical bone gain reached more than 10mm without the use of bone transplantation. Certain complications like incorrect vector of distraction, paresthesia, pain and loss of transport segment were encountered during the course of the study. CONCLUSION: Alveolar vertical distraction osteogenesis is a reliable and predictable technique for both hard and soft tissue genesis. Implant placement is feasible with primary stability in neogenerated bone at the level of the distracted areas.

6.
Indian J Dent Res ; 25(5): 667-71, 2014.
Article in English | MEDLINE | ID: mdl-25511071

ABSTRACT

Dentofacial deformities involve deviations from the normal facial proportions and dental relationships and can range from mild to being severe enough to be severely handicapping.The term handicapping malocclusions though not a term commonly used, involves a fortunately small section (2-4%) of patients who can suffer from esthetic,psychological and functional problems. Craniofacial Orthodontics is the area of orthodontics that treats patients with congenital and acquired deformities of the integument and it's underlying musculoskeletal system within the craniofacial area and associated structures.This case report of a young woman with severe mandibular deficiency and facial asymmetry due to condylar ankylosis highlights the importance of team work in rehabilitation of such severe craniofacial deformities.


Subject(s)
Ankylosis/complications , Dentofacial Deformities/therapy , Facial Asymmetry/therapy , Mandible/abnormalities , Temporomandibular Joint Disorders/complications , Bicuspid/surgery , Cephalometry/methods , Dentofacial Deformities/etiology , Dentofacial Deformities/surgery , Facial Asymmetry/etiology , Facial Asymmetry/surgery , Female , Humans , Mandible/surgery , Molar/surgery , Osteogenesis, Distraction/methods , Palatal Expansion Technique , Patient Care Planning , Retrognathia/etiology , Retrognathia/therapy , Tooth Extraction , Tooth Movement Techniques/methods , Tooth, Impacted/surgery , Young Adult
7.
Glycobiology ; 23(10): 1131-41, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23887940

ABSTRACT

At weaning, the intestinal mucosa surface glycans change from predominantly sialylated to fucosylated. Intestinal adaptation from milk to solid food is regulated by intrinsic and extrinsic factors. The contribution by glucocorticoid, an intrinsic factor, and colonization by microbiota, an extrinsic factor, was measured as the induction of α1,2/3-fucosyltransferase and sucrase-isomaltase (SI) activity and gene expression in conventionally raised, germ-free, and bacteria-depleted mice. In conventionally raised mice, cortisone acetate (CA) precociously accelerated SI gene expression up to 3 weeks and fut2 to 4 weeks of age. In germ-free mice, CA treatment induces only SI expression but not fucosyltransferase. In post-weaning bacteria-deficient (germ-free and bacteria-depleted) mice, fut2 expression remains at low suckling levels. In microbiota deficient mice, intestinal fut2 (but not fut1, fut4 or fut7) was induced only by adult microbiota, but not immature microbiota or CA. Fut2 induction could also be restored by colonization by Bacteroides fragilis, but not by a B. fragilis mutant unable to utilize fucose. Restoration of fut2 expression (by either microbiota or B. fragilis) in bacteria-depleted mice is necessary for recovery from dextran sulfate sodium-induced mucosal injury. Thus, glucocorticoids and microbes regulate distinct aspects of gut ontogeny: CA precociously accelerates SI expression and, only in colonized mice, fut2 early expression. The adult microbiota is required for the fut2 induction responsible for the highly fucosylated adult gut phenotype and is necessary for recovery from intestinal injury. Fut2-dependent recovery from inflammation may explain the high incidence of inflammatory disease (Crohn's and necrotizing enterocolitis) in populations with mutant FUT2 polymorphic alleles.


Subject(s)
Cortisone/analogs & derivatives , Fucosyltransferases/metabolism , Intestines/enzymology , Microbiota , Animals , Bacteroides fragilis , Cortisone/pharmacology , Fucose/metabolism , Fucosyltransferases/genetics , Homeostasis , Intestines/drug effects , Intestines/microbiology , Mice , Sucrase-Isomaltase Complex/genetics , Sucrase-Isomaltase Complex/metabolism , Galactoside 2-alpha-L-fucosyltransferase
8.
J Pediatr Gastroenterol Nutr ; 54(5): 630-8, 2012 May.
Article in English | MEDLINE | ID: mdl-22067113

ABSTRACT

OBJECTIVES: Breast milk transforming growth factor (TGF)-ß2 is associated with healthy immune maturation and reduced risk of immune-mediated disease in infants. We sought to investigate whether conditioning with TGF-ß2 may result in a more mature immune responder phenotype in immature human intestinal epithelial cells (IECs). METHODS: Primary human fetal IECs (hFIECs) and the human fetal small intestinal epithelial cell line (H4 cells) were conditioned with breast milk levels of TGF-ß2, and an inflammatory response was subsequently induced. Inflammatory cytokine secretion and mRNA expression were measured by enzyme-linked immunosorbent assay and quantitative real-time polymerase chain reaction, respectively. Alterations in activation of inflammatory signaling pathways were detected from IECs by immunoblotting and immunofluorescence. The effects of TGF-ß2 conditioning on gene expression patterns in hFIECs were assessed by cDNA microarray analysis and quantitative PCR. RESULTS: Conditioning with TGF-ß2 significantly attenuated subsequent interleukin (IL)-1ß-, TNF-α-, and poly I:C-induced IL-8 and IL-6 responses in immature human IECs. Conditioning with TGF-ß2 inhibited IL-1ß-induced IκB-α degradation and NF-κB p65 nuclear translocation, which may partially result from TGF-ß2-induced changes in the expression of genes in the NF-κB signaling pathway detected by cDNA microarray and qPCR. CONCLUSIONS: Conditioning with TGF-ß2 attenuates the subsequent inflammatory cytokine response in immature human IECs by inhibiting signaling in the NF-κB pathway. The immunomodulatory potential of breast milk may in part be mediated by TGF-ß2, which may provide a novel means of supporting intestinal immune maturation in neonates.


Subject(s)
Epithelial Cells/metabolism , Intestines/growth & development , NF-kappa B/metabolism , Transforming Growth Factor beta2/pharmacology , Cell Line , Enzyme-Linked Immunosorbent Assay , Epithelial Cells/cytology , Gene Expression , Humans , I-kappa B Kinase/antagonists & inhibitors , I-kappa B Kinase/metabolism , Interleukin-1/antagonists & inhibitors , Interleukin-1/metabolism , Interleukin-1beta/metabolism , Interleukin-6/metabolism , Interleukin-8/metabolism , Intestines/cytology , Milk, Human/chemistry , Oligonucleotide Array Sequence Analysis , Real-Time Polymerase Chain Reaction , Signal Transduction , Tumor Necrosis Factor-alpha/metabolism
9.
Neonatology ; 99(3): 192-201, 2011.
Article in English | MEDLINE | ID: mdl-20881435

ABSTRACT

BACKGROUND: Breast milk is known to protect the infant against infectious and immuno-inflammatory diseases, but the mechanisms of this protection are poorly understood. OBJECTIVES: We hypothesized that transforming growth factor-ß2 (TGF-ß2), an immunoregulatory cytokine abundant in breast milk, may have a direct anti-inflammatory effect on immature human intestinal epithelial cells (IECs). METHODS: Human fetal ileal organ culture, primary human fetal IECs, and the human fetal small intestinal epithelial cell line H4 were stimulated with interleukin 1ß (IL-1ß) with or without TGF-ß2. Pro-inflammatory cytokine secretion and mRNA expression were measured by ELISA and quantitative real-time polymerase chain reaction, respectively. Alterations in ERK signalling were detected from IECs by immunoblotting and in fetal ileal tissue culture by immunohistochemistry. SMAD6 knockdown was performed by transfecting the cells with SMAD6 siRNA. RESULTS: TGF-ß2 significantly attenuated IL-1ß-induced pro-inflammatory cytokine production in fetal intestinal organ culture and the cell culture models. In addition, TGF-ß2 reduced the IL-1ß-induced IL-8 and IL-6 mRNA response in H4 cells. TGF-ß2 markedly inhibited IL-1ß-induced phosphorylation of ERK, which was necessary for the cytokine response. The inhibitory effect of TGF-ß2 on IL-1ß-induced cytokine production was completely abrogated by SMAD6 siRNA knockdown. CONCLUSIONS: TGF-ß2 attenuates IL-1ß-induced pro-inflammatory cytokine production in immature human IECs by inhibiting ERK signalling. The anti-inflammatory effect of TGF-ß2 is dependent on SMAD6. Breast milk TGF-ß2 may provide the neonate with important immunoregulatory support. TGF-ß2 might provide a novel means to improve intestinal immunophysiology in premature neonates.


Subject(s)
Extracellular Signal-Regulated MAP Kinases/immunology , Interleukin-1beta/immunology , Intestine, Small/immunology , Milk, Human/immunology , Smad6 Protein/immunology , Transforming Growth Factor beta2/pharmacology , Cell Line , Epithelial Cells/cytology , Epithelial Cells/immunology , Extracellular Signal-Regulated MAP Kinases/antagonists & inhibitors , Fetus , Flavonoids/pharmacology , Humans , In Vitro Techniques , Infant, Newborn , Interleukin-6/genetics , Interleukin-6/immunology , Interleukin-8/genetics , Interleukin-8/immunology , Intestine, Small/cytology , Protein Kinase Inhibitors/pharmacology , RNA, Messenger/chemistry , RNA, Messenger/genetics , RNA, Small Interfering/pharmacology , Reverse Transcriptase Polymerase Chain Reaction , Smad6 Protein/antagonists & inhibitors
10.
Am J Physiol Gastrointest Liver Physiol ; 293(4): G780-7, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17673542

ABSTRACT

The intestinal epithelium of the adult gut supports a complex, dynamic microbial ecosystem and expresses highly fucosylated glycans on its surface. Uncolonized gut contains little fucosylated glycan. The transition toward adult colonization, such as during recovery from germ-free status or from antibiotic treatment, increased expression of fucosylated epitopes in the colonic epithelium. This increase in fucosylation is accompanied by induction of fut2 mRNA expression and alpha1,2/3-fucosyltransferase activity. Colonization stimulates ERK and JNK signal transduction pathways, resulting in activation of transcription factors ATF2 and c-Jun, respectively. This increases transcription of fut2 mRNA and expression of alpha1,2/3-fucosyltransferase activity, resulting in a highly fucosylated intestinal mucosa characteristic of the adult mammalian gut. Blocking the ERK and JNK signaling cascade inhibits the ability of colonization to induce elevated fut2 mRNA and fucosyltransferase activity in the mature colon. Thus pioneer-mutualist symbiotic bacteria may utilize the ERK and JNK signaling cascade to induce the high degree of fucosylation characteristic of adult mammalian colon, and we speculate that this fucosylation facilitates colonization by adult microbiota.


Subject(s)
Colon/microbiology , Extracellular Signal-Regulated MAP Kinases/physiology , Fucosyltransferases/physiology , Intestinal Mucosa/microbiology , JNK Mitogen-Activated Protein Kinases/physiology , Signal Transduction/physiology , Symbiosis , Animals , Germ-Free Life , Mice , Galactoside 2-alpha-L-fucosyltransferase
11.
Pediatr Res ; 62(2): 139-44, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17597654

ABSTRACT

Zinc deficiency enhances infectious diarrhea whereas probiotics may inhibit pathogen enterocyte invasion. The effect of probiotics on zinc-deficient versus normal human intestinal epithelium (Caco-2 and T-84) with regard to invasion and subsequent inflammatory response by Salmonella typhimurium was determined. Cells were infected with pathogens and preincubated with media conditioned by several lactobacilli or Bifidobacterium bifidum 12. Pathogen invasion was quantified, inflammation was determined by IL-8 secretion, and MAP kinase activation in the epithelium was analyzed. Probiotic inhibiting factors were partially characterized based on physicochemical properties. Zinc deficiency allowed for greater pathogen invasion and enhanced IL-8 secretion. Probiotic conditioned media reduced activation of proinflammatory signaling via the ERK and p38 pathway. Probiotic factors reverse increased susceptibility of zinc-deficient enterocytes to S. typhimurium invasion, suggesting an additive protective effect of probiotics in zinc deficiency. Probiotic conditioned media but not bacteria inhibited pathogen invasion and IL-8 production in zinc deficient enterocytes. Probiotic inhibitory factors are stable to treatment with proteases, deoxyribonucleases (DNAses), ribonucleases (RNAse), strong acid, and heat.


Subject(s)
Bifidobacterium/metabolism , Enterocytes/drug effects , Intestinal Mucosa/drug effects , Lactobacillus/metabolism , Probiotics/pharmacology , Salmonella Infections/prevention & control , Salmonella typhimurium/drug effects , Zinc/deficiency , Caco-2 Cells , Culture Media, Conditioned/metabolism , Deoxyribonucleases/metabolism , Dose-Response Relationship, Drug , Enterocytes/enzymology , Enterocytes/metabolism , Enterocytes/microbiology , Enterocytes/pathology , Enzyme Activation , Extracellular Signal-Regulated MAP Kinases/metabolism , Hot Temperature , Humans , Hydrogen-Ion Concentration , Inflammation/metabolism , Inflammation/microbiology , Inflammation/prevention & control , Interleukin-8/metabolism , Intestinal Mucosa/enzymology , Intestinal Mucosa/metabolism , Intestinal Mucosa/microbiology , Intestinal Mucosa/pathology , Peptide Hydrolases/metabolism , Probiotics/metabolism , Probiotics/therapeutic use , Ribonucleases/metabolism , Salmonella Infections/metabolism , Salmonella Infections/microbiology , Salmonella typhimurium/isolation & purification , Salmonella typhimurium/pathogenicity , Signal Transduction/drug effects , p38 Mitogen-Activated Protein Kinases/metabolism
12.
Glycobiology ; 15(3): 221-32, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15483270

ABSTRACT

Intestinal maturation can be influenced by intrinsic factors (glucocorticoid hormones) and by extrinsic factors (resident microflora); their relative roles in ontogeny of mouse intestinal trehalase expression, a marker of general gut development, and of beta1,4-galactosyltransferase (beta GT), a marker of glycosyltransferase development, were investigated. In conventional (CONV) mice, beta GT and trehalase gene expression rapidly increased to adult levels by the fourth postnatal week. In germ-free (GF) mice, beta GT expression remained at initial low levels and was rapidly induced on reintroduction of luminal microbes of the adult gut but not of microbes characteristic of the suckling gut. Similar developmental patterns were observed for colonic galactosyl beta1,4-linked glycoconjugates, products of beta GT activity. These results indicate an essential role for microbes in the ontogeny of beta GT. In both CONV and GF mice, cartisone acetate (CA) precociously accelerated the ontogeny of beta GT and trehalase until maturation of the gut occurred (day 22). In the mature gut of CONV mice, both beta GT and trehalase are elevated and insensitive to CA; in GF mature mice, the expression of beta GT remains low, whereas the expression of trehalase was at mature levels, regardless of CA treatment. These changes in enzyme activity were accompanied by parallel changes in mRNA, implying transcriptional regulation. Thus both microbes and cortisone regulate gut ontogeny, but only suckling gut responds to CA, an intrinsic factor, whereas adult gut beta GT expression remains sensitive to microflora, an extrinsic factor. However, induction of the adult pattern of glycosyltransferase expression in mature gut requires colonization by microflora typical of adult gut, suggesting an essential role for intestinal colonization in the ontogeny of normal intestinal mucosal cell surface glycoconjugate receptors.


Subject(s)
Cortisone/analogs & derivatives , Galactosyltransferases/metabolism , Glucocorticoids/pharmacology , Intestines/enzymology , Intestines/microbiology , Trehalase/metabolism , Animals , Cortisone/pharmacology , Intestines/drug effects , Mice , Spectrometry, Fluorescence
13.
Am J Physiol Gastrointest Liver Physiol ; 288(1): G85-92, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15591589

ABSTRACT

Necrotizing enterocolitis (NEC) is a major inflammatory disease of the premature human intestine that can be prevented by glucocorticoids if given prenatally before the 34th wk of gestation. This observation suggests that a finite period of steroid responsiveness exists as has been demonstrated in animal models. Human intestinal xenografts were used to determine whether a glucocorticoid responsive period exists in the developing human intestine. Developmental responsiveness was measured by lactase activity and inflammatory responsiveness by IL-8, IL-6, and monocyte chemotactic protein-1 (MCP-1) induction after an endogenous (IL-1 beta) or exogenous (LPS) proinflammatory stimulus, respectively. Functional development of ileal xenografts were monitored for 30 wk posttransplantation, and the lactase activity recapitulated that predicted by in utero development. Cortisone acetate accelerated the ontogeny of lactase at 20 wk (immature) but the effect was lost by 30 wk (mature) posttransplant. Concomitant with accelerated maturation, the IL-8 response to both IL-1 beta and LPS was significantly dampened (from 6- to 3-fold) by glucocorticoid pretreatment in the immature but not mature xenografts. The induction of IL-8 was reflected at the level of IL-8 mRNA, suggesting transcriptional regulation. The excessive activation of IL-8 in the immature gut was mediated by a prolonged activation of ERK and p38 kinases and nuclear translocation of NF-kappa B due to low levels of I kappa B. Steroid pretreatment in immature intestine dampens activation of all three signaling pathways in response to proinflammatory stimuli. Therefore, accelerating intestinal maturation by glucocorticoids within the responsive period by accelerating functional and inflammatory maturation may provide an effective preventive therapy for NEC.


Subject(s)
Cortisone/analogs & derivatives , Enterocolitis, Necrotizing/prevention & control , Enterocolitis, Necrotizing/physiopathology , Glucocorticoids/pharmacology , Ileum/embryology , Ileum/growth & development , Animals , Child , Child, Preschool , Cortisone/pharmacology , Humans , Ileum/pathology , Infant , Infant, Newborn , Inflammation , Interleukin-8/biosynthesis , Interleukin-8/pharmacology , Mice , Mice, SCID , Signal Transduction , Transcription, Genetic , Transplantation, Heterologous
14.
Am J Physiol Regul Integr Comp Physiol ; 285(1): R162-70, 2003 Jul.
Article in English | MEDLINE | ID: mdl-12560204

ABSTRACT

The aim of this study was to determine whether intestinal xenografts could recapitulate human in utero development by using disaccharidases as markers. Twenty-week-old fetal intestine was transplanted into immunocompromised mice and was followed. At 20-wk of gestation, the fetal human intestine was morphologically developed with high sucrase and trehalase but had low lactase activities. By 9-wk posttransplantation, jejunal xenografts were morphologically and functionally developed and were then monitored for

Subject(s)
Cortisone/analogs & derivatives , Cortisone/pharmacology , Fetal Tissue Transplantation , Jejunum/transplantation , Animals , Biomarkers , Humans , Jejunum/enzymology , Jejunum/growth & development , Lactase , Mice , Mice, Nude , Mice, SCID , Sucrase/metabolism , Transplantation, Heterologous , Trehalase/metabolism , beta-Galactosidase/metabolism
15.
FASEB J ; 17(1): 44-6, 2003 Jan.
Article in English | MEDLINE | ID: mdl-12475916

ABSTRACT

Most enteric bacteria use intestinal brushborder glycoconjugates as their target host cell receptors. It has been postulated that resident microbes regulate specific glycosyltransferases that are responsible for synthesizing brushborder glycoconjugates. To investigate this hypothesis, we measured glycosyltransferase enzyme activities in intestine from different regions of maturing conventional (CONV), germ-free (GF), and ex-germ-free (XGF) mice and compared them to general enzyme markers of gut development, for example, disaccharidases. High alpha2,3/6-Sialyltransferase (ST) activity and low alpha1,2-fucosyltransferase (FT) activities were detected from duodenum to colon in suckling CONV mice, but the relative levels of these activities reversed during the third postnatal wk, rapidly reaching adult levels by the fourth wk. These age-related enzyme changes were significantly attenuated in GF mice, maintaining an immature pattern well past 3 wk. Introduction of gut microflora in GF mice rapidly initiated maturation of glycosyltransferase activity but had no significant affect on developmental programming of dissacharidases. Therefore, in mice, intestinal glycosyltransferase activities are under tissue and developmental control and microflora play a major role in their specific ontogeny but not in overall development. These findings may help explain the regional specificity of commensal bacteria and of enteric pathogens and may also relate age-related changes in microflora to susceptibility to enteropathogens.


Subject(s)
Fucosyltransferases/metabolism , Intestinal Mucosa/enzymology , Intestinal Mucosa/microbiology , Sialyltransferases/metabolism , Age Factors , Animals , Disaccharidases/metabolism , Intestinal Mucosa/growth & development , Mice , Microvilli/enzymology , Organ Specificity , Specific Pathogen-Free Organisms
16.
Am J Physiol Gastrointest Liver Physiol ; 282(3): G480-90, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11841998

ABSTRACT

Regional differences in the ontogeny of mouse intestinal alpha-2,6-sialyltransferase activities (alpha-2,6-ST) and the influence of cortisone acetate (CA) on this expression were determined. High ST activity and alpha-2,6-ST mRNA levels were detected in immature small and large intestine, with activity increasing distally from the duodenum. As the mice matured, ST activity (predominantly alpha-2,6-ST) in the small intestine decreased rapidly to adult levels by the fourth postnatal week. CA precociously accelerated this region-specific ontogenic decline. A similar decline of ST mRNA levels reflected ST activity in the small, but not the large, intestine. Small intestinal sialyl alpha-2,6-linked glycoconjugates displayed similar developmental and CA induced-precocious declines when probed using Sambucus nigra agglutinin (SNA) lectin. SNA labeling demonstrated age-dependent diminished sialyl alpha2,6 glycoconjugate expression in goblet cells in the small (but not large) intestine, but no such regional specificity was apparent in microvillus membrane. This suggests differential regulation of sialyl alpha-2,6 glycoconjugates in absorptive vs. globlet cells. These age-dependent and region-specific differences in sialyl alpha-2,6 glycoconjugates may be mediated in part by altered alpha-2,6-ST gene expression regulated by trophic factors such as glucocorticoids.


Subject(s)
Aging , Cortisone/pharmacology , Intestines/enzymology , Intestines/growth & development , Plant Lectins , Sialyltransferases/metabolism , Animals , Animals, Suckling , Asialoglycoproteins/metabolism , Carbohydrate Conformation , Colon/enzymology , Duodenum/enzymology , Fetuins , Fluorescein-5-isothiocyanate , Fluorescent Dyes , Glycoconjugates/analysis , Ileum/enzymology , Intestines/drug effects , Jejunum/enzymology , Lectins , Mice , N-Acetylneuraminic Acid/metabolism , RNA, Messenger/analysis , Ribosome Inactivating Proteins , Sialyltransferases/genetics , Tissue Distribution , alpha-Fetoproteins/metabolism
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