scholarly journals The abundance of Akkermansia muciniphila and its relationship with sulphated colonic mucins in health and ulcerative colitis

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Helen Earley ◽  
Grainne Lennon ◽  
Áine Balfe ◽  
J. Calvin Coffey ◽  
Desmond C. Winter ◽  
...  

Abstract Akkermansia muciniphila utilises colonic mucin as its substrate. Abundance is reduced in ulcerative colitis (UC), as is the relative proportion of sulphated mucin in the mucus gel layer (MGL). It is unknown if these phenomena are related, however reduced sulphated mucins could contribute to reduced abundance, owing to a lack of substrate. The aim of this study was to quantify A. muciniphila within the MGL and to relate these findings with markers of inflammation and the relative proportion of sulphomucin present. Colonic biopsies and mucus brushings were obtained from 20 patients with active UC (AC), 14 with quiescent UC (QUC) and 20 healthy controls (HC). A. muciniphila abundance was determined by RT-PCR. High iron diamine alcian-blue staining was performed for histological analysis. Patients with AC had reduced abundance of A. muciniphila compared to HC and QUC. A positive association was found between A. muciniphila abundance and higher percentage of sulphated mucin (ρ 0.546, p = 0.000). Lower abundances of A. muciniphila correlated with higher inflammatory scores (ρ = 0.294 (p = 0.001)). This study confirms an inverse relationship between A. muciniphila and inflammation and a positive association between A. muciniphila abundance and percentage of sulfated mucin in the MGL.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Helen Earley ◽  
Grainne Lennon ◽  
J. Calvin Coffey ◽  
Desmond C. Winter ◽  
P. Ronan O’Connell

AbstractButyrate is the primary energy source for colonocytes and is essential for mucosal integrity and repair. Butyrate deficiency as a result of colonic dysbiosis is a putative factor in ulcerative colitis (UC). Commensal microbes are butyrogenic, while others may inhibit butyrate, through hydrogenotropic activity. The aim of this study was to quantify butyrogenic and hydrogenotropic species and determine their relationship with inflammation within the colonic mucus gel layer (MGL). Mucosal brushings were obtained from 20 healthy controls (HC), 20 patients with active colitis (AC) and 14 with quiescent colitis (QUC). Abundance of each species was determined by RT-PCR. Inflammatory scores were available for each patient. Statistical analyses were performed using Mann–Whitney-U and Kruskall-Wallis tests. Butyrogenic R. hominis was more abundant in health than UC (p < 0.005), prior to normalisation against total bacteria. Hydrogenotropic B. wadsworthia was reduced in AC compared to HC and QUC (p < 0.005). An inverse correlation existed between inflammation and R. hominis (ρ − 0.460, p < 0.005) and B. wadsworthia (ρ − 0.646, p < 0.005). Other hydrogenotropic species did not widely colonise the MGL. These data support a role for butyrogenic bacteria in UC. Butyrate deficiency in UC may be related to reduced microbial production, rather than inhibition by microbial by-products.


2020 ◽  
Author(s):  
Helen Earley ◽  
Grainne Lennon ◽  
Desmond Winter ◽  
Calvin Coffey ◽  
Ronan O'Connell

Abstract Butyrate is the primary energy source for colonocytes and is essential for mucosal integrity and repair. Butyrate deficiency as a result of colonic dysbiosis is a putative factor in ulcerative colitis (UC). Commensal microbes are butyrogenic, while others have an inhibitory effect, through hydrogenotropic activity. The aim of this study was to quantify butyrogenic and hydrogenotropic species and determine their relationship with inflammation within the colonic mucus gel layer (MGL).Mucosal brushings were obtained from 20 patients with active colitis (AC), 20 healthy controls (HC) and 14 with quiescent colitis (QUC). Abundance of each species was determined by RT-PCR. Inflammatory scores were available for each patient. Statistical analyses were performed using Mann-Whitney-U and Kruskall-Wallis tests.Butyrogenic R. hominis was more abundant in health than UC (p<0.005). Hydrogenotropic B. wadsworthia was reduced in AC compared to HC and QUC (p<0.005). An inverse correlation existed between inflammation and R. hominis (ρ -0.460, p >0.005) and B. wadsworthia (ρ -0.646, p >0.005). Other hydrogenotropic species did not widely colonise the MGL. These data support a role for butyrogenic and some species of hydrogenotropic bacteria in UC. Butyrate deficiency in UC may be related to reduced microbial production, rather than inhibition by microbial by-products.


2014 ◽  
Vol 51 (2) ◽  
pp. 107-112 ◽  
Author(s):  
Luiz Gustavo de OLIVEIRA ◽  
André Luiz da CUNHA ◽  
Amaury Caiafa DUARTE ◽  
Maria Christina Marques Nogueira CASTAÑON ◽  
Júlio Maria Fonseca CHEBLI ◽  
...  

ContextInflammatory bowel disease, including ulcerative colitis and Crohn’s disease, comprising a broad spectrum of diseases those have in common chronic inflammation of the gastrointestinal tract, histological alterations and an increased activity levels of certain enzymes, such as, metalloproteinases.ObjectivesEvaluate a possible correlation of disease activity index with the severity of colonic mucosal damage and increased activity of metalloproteinases in a model of ulcerative colitis induced by dextran sulfate sodium.MethodsColitis was induced by oral administration of 5% dextran sulfate sodium for seven days in this group (n=10), whereas control group (n=16) received water. Effects were analyzed daily by disease activity index. In the seventh day, animals were euthanized and hematological measurements, histological changes (hematoxylin and eosin and Alcian Blue staining), myeloperoxidase and metalloproteinase activities (MMP-2 and MMP-9) were determined.ResultsDextran sulfate sodium group showed elevated disease activity index and reduced hematological parameters. Induction of colitis caused tissue injury with loss of mucin and increased myeloperoxidase (P<0.001) and MMP-9 activities (45 fold) compared to the control group.ConclusionsIn this study, we observed a disease activity index correlation with the degree of histopathological changes after induction of colitis, and this result may be related mainly to the increased activity of MMP-9 and mieloperoxidase.


2003 ◽  
Vol 62 (1) ◽  
pp. 237-243 ◽  
Author(s):  
Vicki Strugala ◽  
Adrian Allen ◽  
Peter W. Dettmar ◽  
Jeffrey P. Pearson

Mucus is a water-insoluble gel secreted by the gastrointestinal tract. It exists as a protective gel layer adherent to the epithelial surface of the stomach, small intestine and colon. The mucus gel is composed of 1–10% (w/v) mucin glycoprotein in a plasma-like fluid. Since the mucus gel is predominantly water, standard histological techniques dehydrate the mucus, making visualisation of the functional barrier difficult. Specialist techniques have been developed to enable visualisation of the intact mucus layer. A simple histological method using snap-frozen tissue, sectioned with a cryostat and stained with modified periodic acid-Schiff s/Alcian blue in mucus-preserving conditions will be described. A second powerfulin vivoanimal model is described which enables measurement of mucus secretion over time. The use of these two methods has allowed the characterisation of the normal mucus layer in the colon and the determination of how it is affected by disease and dietary intervention, in particular the effect of dietary fibre, and evidence that fibre deficiency results in colonic mucosal fragility is presented.


PLoS ONE ◽  
2015 ◽  
Vol 10 (10) ◽  
pp. e0135280 ◽  
Author(s):  
Helen Earley ◽  
Grainne Lennon ◽  
Aine Balfe ◽  
Michelle Kilcoyne ◽  
Marguerite Clyne ◽  
...  

1967 ◽  
Vol 125 (3) ◽  
pp. 409-428 ◽  
Author(s):  
Betsy G. Bang ◽  
Frederik B. Bang

Infectious laryngotracheitis can be produced in chickens as an experimental model of severe nonfatal rhinitis and sinusitis. Inoculated intranasally into unanesthetized baby chicks it remains limited to the nasal fossa, produces acute desquamation of all nasal epithelia, results in functional recovery of the respiratory epithelium, but leaves important residual abnormalities. From the earliest recognizable lesions through 4½ months' convalescence, the principal changes are as follows: 1. Initial lesions, or small syncytia of intranuclear "inclusions", first identifiable in the mucociliated cells of the shallowest portion of the epithelium at about 21 hr postinoculum (the inner surface of the maxillary conchal scroll). 2. Acute sloughing, (about 3 to 7 days), marked by: (a) spread of lesions from cell to cell via multinucleated "giant cells" which progressively slough and desquamate respiratory, olfactory, and sinus epithelia, epithelial neural elements and blood vessels; (b) appearance of numbers of eosinophilic leukocytes along the basement membrane at the sites of lesions just previous to sloughing; intensive infiltration of the submucosa with small lymphocytes after sloughing begins; (c) histochemical change in the intracellular mucus of the cells which comprise the syncytia: this mucus stains with Alcian blue alone when stained with AB-PAS; and (d) all cartilages of the maxillary conchae become flaccid, and the cell nuclei and matrix lose both basophilic and Alcian blue staining properties, effects which recede by about the 8th day. 3. Repair (about 8 to 21 days), marked by rapid initial spread of a sheet of epithelial cells over the infiltrated subrmucosa, appearance of numbers of plasma cells circulating in the tissues, formation of encapsulated secondary nodules, and mucosal adhesions. 4. Convalescence (about 1 to 4½ months when experiments terminated), marked by functional restoration of the mucociliary lining of the nasal fossa. However, at 4½ months eight specimens all show complete metaplasia of the olfactory organ (end nerves, supporting cells, and glands of Bowman) to mucociliated epithelium, all show abnormal formation and alignment of mucous acini, and about 50% have severe persistent sinusitis.


Parasitology ◽  
1969 ◽  
Vol 59 (3) ◽  
pp. 505-518 ◽  
Author(s):  
R. E. Howells ◽  
D. A. Erasmus

Regional differences in the tegumentary tissue of Moniezia expansa, as revealed at the light-microscope level by histological and histochemical techniques, are described and evidence for secretory activity by the interproglottidal glands is presented.In very immature proglottides the interproglottidal glands are at the ‘precryptic’ stage. Gland cells may be differentiated from other tegumentary cells by their high RNA content and in certain gland cells the presence of an alcian blue staining material.In mature proglottides the glands consist of rosette-like clusters of cells around crypt-like intuckings of the tegument. Two types of cells are found in the gland, small alcian blue-staining cells which are most numerous in the neck region of the crypt, and larger cells, the predominant gland cells, which do not stain with alcian blue but possess non-specific esterase activity. No other tegumentary cells in Moniezia exhibit this activity. Esterase and phosphatase activity is found in the tegument and crypt of the glands and in the interproglottidal folds.The non-enzyme histochemistry confirms and extends the observations of previous workers.Cytochrome oxidase and succinic dehydrogenase were detected in the tegumentary cells and tegument. Very strong reactions were given in the neck and scolex, with a progressive diminution of activity posteriorly along the strobila. Very low activities were recorded in the tegument of the glands.


1997 ◽  
Vol 110 (21) ◽  
pp. 2691-2701 ◽  
Author(s):  
N.S. Stott ◽  
C.M. Chuong

Members of the vertebrate hedgehog gene family (HH) are involved in patterning and modulation of differentiation. Recently it has been shown that ectopic expression of HH gene family members in vivo blocks chondrocyte maturation through activation of a parathyroid hormone related peptide (PTHrP) dependent negative regulatory loop in the perichondrium. However, the direct effect of HH on chondrocyte maturation has not been tested. Here, we studied the effect of retroviral overexpression of the chicken sonic hedgehog gene (Shh) on the growth and maturation of limb bud cells in micromass cultures. Shh is neither expressed nor required for the initiation of cellular condensation in normal micromass cultures. With Shh over-expression, micromass cultures developed novel tightly whorled nodules in addition to the normal Alcian Blue positive cartilage nodules. We characterized the new nodules and showed that they are strongly positive for alkaline phosphatase, enriched in type X collagen and weakly positive for Alcian Blue staining. Shh overexpression also increased cell proliferation, but this cannot account for the formation of the new nodules. This current study shows that misexpression of Shh in in vitro chondrogenic cultures promotes characteristics of hypertrophic chondrocytes. Thus HH has two complementary functions; a direct positive effect on chondrocyte hypertrophy in the absence of PTHrP pathway, and an indirect negative feedback loop through PTHrP to prevent other less differentiated chondrocytes from becoming hypertrophic. These two complementary actions of HH coordinate the progression of cartilage maturation.


Development ◽  
1986 ◽  
Vol 94 (1) ◽  
pp. 189-205
Author(s):  
Betty C. Gallagher

The developing chick lung was examined in the electron microscope for intimate cell contacts between epithelium and mesenchyme, discontinuities in the basal lamina and substructure of the basement membrane. Cell filopodia were seen which crossed the basal lamina from both the epithelial and the mesenchymal cells. Ruthenium red and tannic acid staining of the basal lamina of the chick lung showed it to be thin and sometimes discontinuous at the tips compared to the more substantial basal lamina in the interbud areas. The bilaminar distribution of particles seen with ruthenium red is similar to those seen in the cornea and lens. With tannic acid staining, filaments could be seen which crossed the lamina lucida and connected with the lamina densa. Spikes perpendicular to the basal lamina were sometimes seen with a periodicity of approximately 110 nm. Alcian blue staining revealed structure similar to that seen by ruthenium red staining in the salivary and mammary glands, although the interparticle spacing was closer. Collagen was located in areas of morphogenetic stability, as has been seen by other investigators in different tissues. Collagen was coated with granules (probably proteoglycan) at periodic intervals when stained with ruthenium red. The fibrils were oriented circumferentially around the mesobronchus and were assumed to continue into the bud, but the fibres curve laterally at the middle of a bud. This orientation is opposite to that seen by another investigator in the mouse lung. In general, the observations made in the avian lung are similar to those seen in branching mammalian tissue. It is likely, therefore, that the chick lung uses strategies in its morphogenesis that are similar to those that have been elucidated previously in developing mammalian organs.


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