scholarly journals Differential protein abundance and function of UT-B urea transporters in human colon

2010 ◽  
Vol 298 (3) ◽  
pp. G345-G351 ◽  
Author(s):  
D. Collins ◽  
D. C. Winter ◽  
A. M. Hogan ◽  
L. Schirmer ◽  
A. W. Baird ◽  
...  
Keyword(s):  
Intestinal Bacteria ◽  
Human Colon ◽  
Immunoblot Analysis ◽  
Cellular Level ◽  
Gut Bacteria ◽  
Protein Abundance ◽  
Urea Transport ◽  
Ascending Colon ◽  
Differential Protein ◽  
Descending Colon

Facilitative UT-B urea transporters enable the passage of urea across cell membranes. Gastrointestinal urea transporters are thought to play a significant role in the urea nitrogen salvaging process that occurs between mammalian hosts and their gut bacteria. This study investigated the expression of UT-B urea transporters in different segments of human colon. Immunoblot analysis showed that human colon expressed a 35-kDa glycosylated UT-B protein in the colonic mucosa. The 35-kDa UT-B transporter was predominantly located in plasma membrane-enriched samples ( P < 0.001; n = 6), and its expression was greater in the ascending colon compared with the descending colon ( P < 0.01; n = 3). At the cellular level, UT-B transporters were located throughout colonocytes situated in the upper portion of the colonic crypts. Bidirectional trans-epithelial urea transport was significantly greater in the ascending colon than the descending colon ( P < 0.05; n = 6). In addition, the facilitative urea transporter inhibitor 1,3,dimethylurea significantly reduced urea transport in the ascending colon ( P < 0.05; n = 6) but had no effect in the descending colon (NS; n = 6). These results illustrate differential protein abundance of functional UT-B protein in different sections of the human colon, strongly correlating to regions that contain the largest populations of intestinal bacteria. This study suggests an important role for UT-B urea transporters in maintaining the symbiotic relationship between humans and their gut bacteria.

scholarly journals Changes in neuromuscular structure and functions of human colon during ageing are region-dependent

Gut ◽  
2018 ◽  
Vol 68 (7) ◽  
pp. 1210-1223 ◽  
Author(s):  
John Broad ◽  
Victor W S Kung ◽  
Alexandra Palmer ◽  
Shezan Elahi ◽  
Azadeh Karami ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Muscle Relaxation ◽  
Electrical Field Stimulation ◽  
Human Colon ◽  
The Elderly ◽  
Ascending Colon ◽  
Functional Changes ◽  
Intramuscular Nerve ◽  
Descending Colon ◽  
Oxide Synthase

ObjectiveTo determine if human colonic neuromuscular functions decline with increasing age.DesignLooking for non-specific changes in neuromuscular function, a standard burst of electrical field stimulation (EFS) was used to evoke neuronally mediated (cholinergic/nitrergic) contractions/relaxations in ex vivomuscle strips of human ascending and descending colon, aged 35–91 years (macroscopically normal tissue; 239 patients undergoing cancer resection). Then, to understand mechanisms of change, numbers and phenotype of myenteric neurons (30 306 neurons stained with different markers), densities of intramuscular nerve fibres (51 patients in total) and pathways involved in functional changes were systematically investigated (by immunohistochemistry and use of pharmacological tools) in elderly (≥70 years) and adult (35–60 years) groups.ResultsWith increasing age, EFS was more likely to evoke muscle relaxation in ascending colon instead of contraction (linear regression: n=109, slope 0.49%±0.21%/year, 95% CI), generally uninfluenced by comorbidity or use of medications. Similar changes were absent in descending colon. In the elderly, overall numbers of myenteric and neuronal nitric oxide synthase-immunoreactive neurons and intramuscular nerve densities were unchanged in ascending and descending colon, compared with adults. In elderly ascending, not descending, colon numbers of cell bodies exhibiting choline acetyltransferase immunoreactivity increased compared with adults (5.0±0.6 vs 2.4±0.3 neurons/mm myenteric plexus, p=0.04). Cholinergically mediated contractions were smaller in elderly ascending colon compared with adults (2.1±0.4 and 4.1±1.1 g-tension/g-tissue during EFS; n=25/14; p=0.04); there were no changes in nitrergic function or in ability of the muscle to contract/relax. Similar changes were absent in descending colon.ConclusionIn ascending not descending colon, ageing impairs cholinergic function.

Coculture of primary human colon monolayer with human gut bacteria

2021 ◽  
Author(s):  
Jianbo Zhang ◽  
Victor Hernandez-Gordillo ◽  
Martin Trapecar ◽  
Charles Wright ◽  
Mao Taketani ◽  
...  
Keyword(s):  
Human Colon ◽  
Gut Bacteria ◽  
Human Gut

scholarly journals Fecal Calprotectin, CRP and Leucocytes in IBD Patients: Comparison of Biomarkers With Biopsy Results

2020 ◽  
Author(s):  
Barry D Kyle ◽  
Terence A Agbor ◽  
Shajib Sharif ◽  
Usha Chauhan ◽  
John Marshall ◽  
...  
Keyword(s):  
Ulcerative Colitis ◽  
Fecal Calprotectin ◽  
Dependent Manner ◽  
Ascending Colon ◽  
C Reactive Protein ◽  
Concentration Dependent Manner ◽  
Reactive Protein ◽  
Inflammatory Bowel ◽  
Descending Colon ◽  
Active Inflammation

Abstract Background This study aimed to compare fecal calprotectin (FC) levels with other commonly used parameters as part of patient care during evaluation for inflammatory bowel disease (IBD). Methods We recruited adult IBD patients with ulcerative colitis (UC) and Crohn’s disease (CD) and compared the results of the patient’s biopsy results (i.e., inflamed versus noninflamed) for six sites (i.e., ileum, ascending colon, transverse colon, descending colon, sigmoid colon, rectum) with concentrations of C-reactive protein (CRP), total leucocytes and fecal calprotectin (FC). Results We found that FC was significantly elevated in a concentration-dependent manner that correlated with the number of active inflammation sites reported in biopsy. Although CRP and leucocyte measurements trended upwards in line with inflammation reported from biopsy, the results were highly variable and highlighted poor reliability of these biomarkers for indicating IBD inflammation. Conclusions These results strongly suggest that FC correlates best with biopsy reports and is a superior marker than CRP and leucocytes.

Differential protein abundance during the first month of regeneration of the Caribbean star coral Montastraea cavernosa

Coral Reefs ◽  
2018 ◽  
Vol 38 (1) ◽  
pp. 45-61 ◽  
Author(s):  
Ryan A. Horricks ◽  
Christophe M. Herbinger ◽  
Brandon N. Lillie ◽  
Paul Taylor ◽  
John S. Lumsden
Keyword(s):  
Protein Abundance ◽  
Differential Protein ◽  
The Caribbean ◽  
Montastraea Cavernosa

Unprepared human colon does not discriminate between solids and liquids

1991 ◽  
Vol 260 (1) ◽  
pp. G13-G16 ◽  
Author(s):  
M. Proano ◽  
M. Camilleri ◽  
S. F. Phillips ◽  
G. M. Thomforde ◽  
M. L. Brown ◽  
...  
Keyword(s):  
Gamma Camera ◽  
Region Of Interest ◽  
Variable Region ◽  
Human Colon ◽  
Colonic Transit ◽  
Diethylenetriaminepentaacetic Acid ◽  
Half Time ◽  
Ascending Colon ◽  
Healthy Male ◽  
Camera System

In five healthy male volunteers, we compared solid and liquid transit though the unprepared colon. 99mTc-diethylenetriaminepentaacetic acid in 10 ml saline was injected into the cecum through an orocecal tube at 1 ml/min immediately after a methacrylate-coated medication capsule was seen to deliver 111In-labeled Amberlite IR-120PLUS pellets (avg diam, 1.0 mm) into the cecum. Segmental transits through the ascending, transverse, descending, and rectosigmoid regions were determined using a dual gamma camera system and a variable region of interest program. There was no difference between solid [half time, 247 +/- 60 (SE) min] and liquid (312 +/- 88 min) emptying from the ascending colon. Colonic transit of solids and liquids was further compared by regional counts and stool outputs at 12 and 24 h. There were no significant differences between solids and liquids (P greater than 0.05). Our data suggest that transit through the unprepared human colon is not different for solids and small volumes of liquids, when these are delivered together to the ascending colon.

Early polyuria and urinary concentrating defect in potassium deprivation

2000 ◽  
Vol 279 (4) ◽  
pp. F655-F663 ◽  
Author(s):  
Hassane Amlal ◽  
Carissa M. Krane ◽  
Qian Chen ◽  
Manoocher Soleimani
Keyword(s):  
Time Course ◽  
Northern Blot Analysis ◽  
Urine Volume ◽  
Urine Osmolality ◽  
Immunoblot Analysis ◽  
Early Event ◽  
Protein Abundance ◽  
Outer Medulla ◽  
Potassium Deprivation ◽  
Concentrating Defect

The time course of the onset of nephrogenic diabetes insipidus and its relationship to aquaporin-2 (AQP2) expression in K+ deprivation (KD) remains unknown. Rats were fed a K+-free diet and killed after 12 h, 1, 2, 3, 6, or 21 days. Serum K+ concentration was decreased only after, but not before, 3 days of a K+-free diet. Urine osmolality, however, decreased as early as 12 h of KD (1,061 ± 26 vs. 1,487 ± 102 mosmol/kgH2O in control, P < 0.01). It decreased further at 24 h (to 858 ± 162 mosmol/kgH2O in KD, P < 0.004) and remained low at 21 days of KD (436 ± 58 mosmol/kgH2O, P < 0.0001 compared with baseline). Water intake decreased at 12 h ( P < 0.002) but increased at 24 h ( P < 0.05) and remained elevated at 21 days of KD. Urine volume increased at 24 h of KD (8 ± 2 to 15 ± 2 ml/24 h, P < 0.05) and remained elevated at 21 days. Immunoblot analysis demonstrated that AQP2 protein abundance in the outer medulla remained unchanged at 12 h ( P > 0.05), decreased at 24 h (∼44%, P < 0.001), and remained suppressed (∼52%, P < 0.03) at 21 days of KD. In the inner medulla the AQP2 protein abundance remained unchanged at both 12 and 24 h of KD. AQP2 protein abundance in the cortex, however, decreased at 12 h (∼47%, P < 0.01) and remained suppressed at 24 h (∼77%, P < 0.001) of KD. Northern blot analysis showed that AQP2 mRNA decreased as early as 12 h of KD in both cortex ( P < 0.02) and outer medulla ( P < 0.01) and remained suppressed afterward. In conclusion, the urinary concentrating defect in KD is an early event and precedes the onset of hypokalemia. These studies further suggest that the very early urinary concentrating defect in KD (after 12 but before 24 h) results primarily from the suppression of cortical AQP2, whereas the later onset of a urinary concentrating defect (after 24 h) also involves a downregulation of medullary AQP2.

scholarly journals Metabolism of Linoleic Acid by Human Gut Bacteria: Different Routes for Biosynthesis of Conjugated Linoleic Acid

2007 ◽  
Vol 189 (6) ◽  
pp. 2566-2570 ◽  
Author(s):  
Estelle Devillard ◽  
Freda M. McIntosh ◽  
Sylvia H. Duncan ◽  
R. John Wallace
Keyword(s):  
Linoleic Acid ◽  
Conjugated Linoleic Acid ◽  
Vaccenic Acid ◽  
Intestinal Bacteria ◽  
Gut Bacteria ◽  
Human Tissues ◽  
Human Gut ◽  
Gram Positive ◽  
Health Promoting

ABSTRACT A survey of 30 representative strains of human gram-positive intestinal bacteria indicated that Roseburia species were among the most active in metabolizing linoleic acid (cis-9,cis-12-18:2). Different Roseburia spp. formed either vaccenic acid (trans-11-18:1) or a 10-hydroxy-18:1; these compounds are precursors of the health-promoting conjugated linoleic acid cis-9,trans-11-18:2 in human tissues and the intestine, respectively.

Characterization of motor patterns in isolated human colon: are there differences in patients with slow-transit constipation?

2012 ◽  
Vol 302 (1) ◽  
pp. G34-G43 ◽  
Author(s):  
Nick J. Spencer ◽  
Melinda Kyloh ◽  
David A. Wattchow ◽  
Anthony Thomas ◽  
Tiong Cheng Sia ◽  
...  
Keyword(s):  
Muscle Tension ◽  
Human Colon ◽  
Slow Transit Constipation ◽  
Organ Bath ◽  
Motor Patterns ◽  
Slow Transit ◽  
Descending Colon ◽  
Transit Constipation

The patterns of motor activity that exist in isolated full-length human colon have not been described. Our aim was to characterize the spontaneous motor patterns in isolated human colon and determine whether these patterns are different in whole colons obtained from patients with slow-transit constipation (STC). The entire colon (excluding the anus), was removed from patients with confirmed STC and mounted longitudinally in an organ bath ∼120 cm in length, containing oxygenated Krebs' solution at 36°C. Changes in circular muscle tension were recorded from multiple sites simultaneously along the length of colon, by use of isometric force transducers. Recordings from isolated colons from non-STC patients revealed cyclical colonic motor complexes (CMCs) in 11 of 17 colons, with a mean interval and half-duration of contractions of 4.0 ± 0.6 min and 51.5 ± 15 s, respectively. In the remaining six colons, spontaneous irregular phasic contractions occurred without CMCs. Interestingly, in STC patients robust CMCs were still recorded, although their CMC pacemaker frequencies were slower. Intraluminal balloon distension of the ascending or descending colon evoked an ascending excitatory reflex contraction, or evoked CMC, in 8 of 30 trials from non-STC (control) colons, but not from colons obtained from STC patients. In many control segments of descending colon, spontaneous CMCs consisted of simultaneous ascending excitatory and descending inhibitory phases. In summary, CMCs can be recorded from isolated human colon, in vitro, but their intrinsic pacemaker frequency is considerably faster in vitro compared with previous human recordings of CMCs in vivo. The observation that CMCs occur in whole colons removed from STC patients suggests that the intrinsic pacemaker mechanisms underlying their generation and propagation are preserved in vitro, despite impaired transit along these same regions in vivo.

scholarly journals Colonization of Cattle Intestines by Campylobacter jejuni and Campylobacter lanienae

2005 ◽  
Vol 71 (9) ◽  
pp. 5145-5153 ◽  
Author(s):  
G. Douglas Inglis ◽  
Lisa D. Kalischuk ◽  
Hilma W. Busz ◽  
John P. Kastelic
Keyword(s):  
Beef Cattle ◽  
Campylobacter Jejuni ◽  
Large Intestine ◽  
Initial Study ◽  
Beef Steers ◽  
Ascending Colon ◽  
Tissue Samples ◽  
Real Time Quantitative Pcr ◽  
Colon And Rectum ◽  
Descending Colon

ABSTRACT The location and abundance of Campylobacter jejuni and Campylobacter lanienae in the intestines of beef cattle were investigated using real-time quantitative PCR in two studies. In an initial study, digesta and tissue samples were obtained along the digestive tract of two beef steers known to shed C. jejuni and C. lanienae (steers A and B). At the time of slaughter, steer B weighed 540 kg, compared to 600 kg for steer A, yet the intestine of steer B (40.5 m) was 36% longer than the intestine of steer A (26.1 m). In total, 323 digesta samples (20-cm intervals) and 998 tissue samples (3.3- to 6.7-cm intervals) were processed. Campylobacter DNA was detected in the digesta and in association with tissues throughout the small and large intestines of both animals. Although C. jejuni and C. lanienae DNA were detected in both animals, only steer A contained substantial quantities of C. jejuni DNA. In both digesta and tissues of steer A, C. jejuni was present in the duodenum and jejunum. Considerable quantities of C. jejuni DNA also were observed in the digesta obtained from the cecum and ascending colon, but minimal DNA was associated with tissues of these regions. In contrast, steer B contained substantial quantities of C. lanienae DNA, and DNA of this bacterium was limited to the large intestine (i.e., the cecum, proximal ascending colon, descending colon, and rectum); the majority of tissue-associated C. lanienae DNA was present in the cecum, descending colon, and rectum. In a second study, the location and abundance of C. jejuni and C. lanienae DNA were confirmed in the intestines of 20 arbitrarily selected beef cattle. DNA of C. jejuni and C. lanienae were detected in the digesta of 57% and 95% of the animals, respectively. C. jejuni associated with intestinal tissues was most abundant in the duodenum, ileum, and rectum. However, one animal contributed disproportionately to the abundance of C. jejuni DNA in the ileum and rectum. C. lanienae was most abundant in the large intestine, and the highest density of DNA of this bacterium was found in the cecum. Therefore, C. jejuni colonized the proximal small intestine of asymptomatic beef cattle, whereas C. lanienae primarily resided in the cecum, descending colon, and rectum. This information could be instrumental in developing efficacious strategies to manage the release of these bacteria from the gastrointestinal tracts of cattle.

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