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Pharmaceutics ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 184
Author(s):  
Michael Schütt ◽  
Connor O’Farrell ◽  
Konstantinos Stamatopoulos ◽  
Caroline L. Hoad ◽  
Luca Marciani ◽  
...  

The performance of solid oral dosage forms targeting the colon is typically evaluated using standardised pharmacopeial dissolution apparatuses. However, these fail to replicate colonic hydrodynamics. This study develops a digital twin of the Dynamic Colon Model; a physiologically representative in vitro model of the human proximal colon. Magnetic resonance imaging of the Dynamic Colon Model verified that the digital twin robustly replicated flow patterns under different physiological conditions (media viscosity, volume, and peristaltic wave speed). During local contractile activity, antegrade flows of 0.06–0.78 cm s−1 and backflows of −2.16–−0.21 cm s−1 were measured. Mean wall shear rates were strongly time and viscosity dependent although peaks were measured between 3.05–10.12 s−1 and 5.11–20.34 s−1 in the Dynamic Colon Model and its digital twin respectively, comparable to previous estimates of the USPII with paddle speeds of 25 and 50 rpm. It is recommended that viscosity and shear rates are considered when designing future dissolution test methodologies for colon-targeted formulations. In the USPII, paddle speeds >50 rpm may not recreate physiologically relevant shear rates. These findings demonstrate how the combination of biorelevant in vitro and in silico models can provide new insights for dissolution testing beyond established pharmacopeial methods.


Metabolites ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 49
Author(s):  
Ambrin Farizah Babu ◽  
Ville Mikael Koistinen ◽  
Soile Turunen ◽  
Gloria Solano-Aguilar ◽  
Joseph F. Urban ◽  
...  

Sterols, bile acids, and acylcarnitines are key players in human metabolism. Precise annotations of these metabolites with mass spectrometry analytics are challenging because of the presence of several isomers and stereoisomers, variability in ionization, and their relatively low concentrations in biological samples. Herein, we present a sensitive and simple qualitative LC–MS/MS (liquid chromatography with tandem mass spectrometry) method by utilizing a set of pure chemical standards to facilitate the identification and distribution of sterols, bile acids, and acylcarnitines in biological samples including human stool and plasma; mouse ileum, cecum, jejunum content, duodenum content, and liver; and pig bile, proximal colon, cecum, heart, stool, and liver. With this method, we detected 24 sterol, 32 bile acid, and 27 acylcarnitine standards in one analysis that were separated within 13 min by reversed-phase chromatography. Further, we observed different sterol, bile acid, and acylcarnitine profiles for the different biological samples across the different species. The simultaneous detection and annotation of sterols, bile acids, and acylcarnitines from reference standards and biological samples with high precision represents a valuable tool for screening these metabolites in routine scientific research.


Molecules ◽  
2021 ◽  
Vol 27 (1) ◽  
pp. 73
Author(s):  
Qiqiong Li ◽  
Florence Van Herreweghen ◽  
Marjan De Mey ◽  
Geert Goeminne ◽  
Tom Van de Wiele

The intestinal absorption of dietary catechins is quite low, resulting in most of them being metabolized by gut microbiota in the colon. It has been hypothesized that microbiota-derived metabolites may be partly responsible for the association between catechin consumption and beneficial cardiometabolic effects. Given the profound differences in gut microbiota composition and microbial load between individuals and across different colon regions, this study examined how microbial (+)-catechin metabolite profiles differ between colon regions and individuals. Batch exploration of the interindividual variability in (+)-catechin microbial metabolism resulted in a stratification based on metabolic efficiency: from the 12 tested donor microbiota, we identified a fast- and a slow-converting microbiota that was subsequently inoculated to SHIME, a dynamic model of the human gut. Monitoring of microbial (+)-catechin metabolites from proximal and distal colon compartments with UHPLC-MS and UPLC-IMS-Q-TOF-MS revealed profound donor-dependent and colon-region-dependent metabolite profiles with 5-(3′,4′-dihydroxyphenyl)-γ-valerolactone being the largest contributor to differences between the fast- and slow-converting microbiota and the distal colon being a more important region for (+)-catechin metabolism than the proximal colon. Our findings may contribute to further understanding the role of the gut microbiota as a determinant of interindividual variation in pharmacokinetics upon (+)-catechin ingestion.


2021 ◽  
Vol 8 ◽  
Author(s):  
Akihito Nakajima ◽  
Tomoyoshi Shibuya ◽  
Takashi Sasaki ◽  
Yu Jie Lu ◽  
Dai Ishikawa ◽  
...  

Nicotine affects the gastrointestinal environment and modulates ulcerative colitis (UC). However, the associations among nicotine, gut metabolites, and UC are still largely unknown. We investigated whether orally administered nicotine affected gut metabolites and dextran sodium sulfate (DSS)-induced colitis. C57BL/6 male mice were orally administered nicotine solution in drinking water prior to inducing DSS-induced colitis. Short-chain fatty acids (SCFAs) and indole in gut contents and fecal samples were measured by GC-MS and hydroxylamine-based indole assays, respectively. Oral administration of nicotine increased indole concentration in feces, but, in contrast, SCFA values did not differ with nicotine administration. Indole levels were increased in the distal colon and rectum but not in the cecum and proximal colon. DSS-induced colitis was less severe clinically and histological changes were minimal in the rectum of orally nicotine-administered mice compared to mice drinking only water. 16S rRNA microbiome on the feces revealed an increasing in Clostridium and Porphyromonas in nicotine-administered mice. In conclusion, nicotine administration was associated with increased indole levels in the distal colon and rectum and attenuated DSS-induced colitis. Oral administration of nicotine may play a potential role in indole upregulation and prevention of UC.


2021 ◽  
Vol 12 ◽  
Author(s):  
Amneris Iraida Castillo Andrade ◽  
Erika García Chávez ◽  
Cecilia Rivera Bautista ◽  
Cuauhtemoc Oros Ovalle ◽  
Miguel Angel Ruiz Cabrera ◽  
...  

The beneficial health of evaluating prebiotic effect by the consumption of Agave salmiana fructans (A. salmiana fructans) was assessed in the epithelium of the cecum and proximal colon of Wistar rats fed at different doses for 35 days with regards to mucus production, morphological cell changes, and the serum concentration of tumor necrosis factor-α (TNF-α). Results showed a significant increase in mucus-secreting cells (P < 0.05) and a normal structure with preserved crypts, without morphological damage to colonic cells for a dose of 12.5% (w/w) with respect to the control and the other doses evaluated. The concentration of pro-inflammatory cytokine TNF-α was decreased significantly (P < 0.05) in the groups with doses of 10 and 12.5% (w/w) at 7 and 35 days, respectively. This effect was positively correlated with the reduction of inflammation in epithelial cells. This study provides direct evidence of the effects of the A. salmiana fructans on the colonic epithelium, demonstrating that a diet supplemented with 12.5% of fructans for 35 days exerts health benefits through the strengthening of the mucosa layer, which favors the adherence of the bacterial population and suppresses inflammation.


2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Jamaji C. Nwanaji-Enwerem ◽  
Chijioke Nze ◽  
Andres Cardenas

Abstract Background Despite the known role of mitosis in colorectal cancer, previous associations of long-term aspirin use with suppressed cancer-related epigenetic aging did not involve epigenetic mitotic clocks. We investigated these relationships using three epigenetic mitotic clocks developed for cancer risk prediction: EpiTOC, EpiTOC2, and MiAge. We utilized publicly available HumanMethylationEPIC BeadChip data from 112 healthy colon (proximal and distal) mucosal samples taken at baseline (T1) and at 10-years follow-up (T2) from a screening cohort of 28 Polish women (11 non-users and 17 long-term [≥ 2 years] aspirin users). Mitotic clock values were divided by chronological age at each timepoint to obtain intrinsic rates (IRs). We evaluated differences in residuals of the mitotic clock IRs taken from linear mixed effects models adjusted for BMI, polyp status, and DNA methylation batch. Findings EpiTOC, EpiTOC2, and MiAge were significantly correlated with chronological age (P < 0.05) with correlations ranging from 0.41 to 0.63. The EpiTOC, EpiTOC2, and MiAge clocks were strongly correlated with each other in proximal and distal samples (r > 0.79, P < 0.0001). We observed proximal within group median clock IR deceleration for EpiTOC (-0.0004 DNAm, P = 0.008), EpiTOC2 (− 16 cell divisions, P = 0.009), and MiAge (− 3 cell divisions, P = 0.002) for long-term aspirin users from T1 to T2 but not for non-users. In distal samples, only the long-term user MiAge IR was significantly deaccelerated (− 3 cell divisions, P = 0.009). Conclusions Our observed findings support previously reported longitudinal associations of aspirin use with deceleration of other epigenetic age measures in the proximal colon. Our mitotic clock results suggest that cell proliferation could play a role in some aspirin relationships with epigenetic aging. Furthermore, the findings provide added impetus for establishing gold standards for epigenetic aging and consensus guidelines for more comprehensive reporting in future epigenetic aging cancer studies.


2021 ◽  
Author(s):  
Gerard Cantero ◽  
Carla Burballa ◽  
Yuki Ohkawa ◽  
Tomohiko Fukuda ◽  
Yoichiro Harada ◽  
...  

Fucosylation of mucins, the main macrocomponents of the mucus layer that protects the digestive tract from pathogens, increases their viscoelasticity and shear stress resistance. These properties are altered in patients with ulcerative colitis (UC), which is marked by a chronic inflammation of the distal part of the colon. Here we show that the levels of Fucosyltransferase 8 (FUT8) and specific mucins are increased in the distal inflamed colon of UC patients compared to normal individuals. Overexpressing FUT8, as observed in UC, in mucin-producing HT29-18N2 colonic cell line increases trafficking of MUC1 to plasma membrane and secretion of MUC2/MUC5AC. FUT8 depletion (FUT8 KD), instead, causes intracellular accumulation of MUC1 and alters the ratio of secreted MUC2 to MUC5AC. Mucins secreted by FUT8 overexpressing cells are more resistant to shear stress compared to mucins secreted by FUT8 KD cells. These data fit well with the Fut8-/- mice phenotype, which are protected against UC. Fut8-/- mice exhibit a thinner proximal colon mucus layer with an altered ratio of neutral to acidic mucins compared to Fut8+/+ mice. Together, these data reveal that FUT8 optimizes the viscoelastic properties of the extracellular mucous by controlling the quantities of mucins secreted.


2021 ◽  
Author(s):  
Su Bum Park ◽  
Seong-Jung Kim ◽  
Jun Lee ◽  
Yoo Jin Lee ◽  
Dong Hoon Baek ◽  
...  

Abstract Background: Endoscopic assessment of disease activity is a key parameter in the management of ulcerative colitis. Whether sigmoidoscopy alone is sufficient to evaluate the disease activity in ulcerative colitis lacks studies. Methods: We retrospectively analyzed the medical records and endoscopic results of patients with ulcerative colitis followed by colonoscopy in seven tertiary hospitals between January 2012 and December 2018. Endoscopic disease activity was scored using the Mayo Endoscopic Score (MES) and Ulcerative Colitis Endoscopic Index of Severity (UCEIS) for each segment from the colonoscopy images. Concordance was evaluated by comparing the highest MES and UCEIS in the rectosigmoid and proximal regions to confirm the usefulness of sigmoidoscopy. Results: A total of 500 colonoscopic examinations from 333 patients were enrolled. Only in 7.6% [k(kappa): 0.893, r(Spearman): 0.906, p<0.001] and 8.6% [k(kappa): 0.890, r(Spearman): 0.914; p<0.001] of cases, MES and UCEIS scored more severely in the proximal colon. Comparison of active disease (MES ≥2) in the rectosigmoid area and the entire colon showed a high concordance rate [k(kappa): 0.899, r(Spearman): 0.904, p<0.001]. Endoscopic healing (MES=0) also showed a high concordance rate [k(kappa): 0.882, r(Spearman): 0.887, p<0.001]. In 38 cases (7.6%) of patients with a higher MES in the proximal area, it was significantly higher in patients with previous extensive colitisConclusions: Sigmoidoscopy and colonoscopy showed a high concordance rate. Therefore, sigmoidoscopy is considered a sufficient substitute for colonoscopy. However, colonoscopy should be considered in patients with previous extensive colitis


Author(s):  
Hiroyuki Nakamori ◽  
Koji Iida ◽  
Hikaru Hashitani

Glucagon-like peptide-1 (GLP-1), a well-known insulin secretagogue, is released from enteroendocrine L cells both luminally and basolaterally to exert different effects. Basolaterally released GLP-1 increases epithelial ion transport by activating CGRP-containing enteric afferent neurons. Although bath-applied GLP-1 reduced the contractility of colonic segments, GLP-1-induced stimulation of afferent neurons could also accelerate peristaltic contractions. Here, the roles of endogenous GLP-1 in regulating colonic peristalsis were investigated using isolated colonic segments. Isolated segments of rat proximal colon were placed in an organ bath, serosally perfused with oxygenated physiological salt solution and luminally perfused with degassed 0.9% saline. Colonic wall motion was recorded using a video camera and converted into spatio-temporal maps. Intraluminal administration of GLP-1 (100 nM) stimulating the secretion of GLP-1 from L cells increased the frequency of oro-aboral propagating peristaltic contractions. The acceleratory effect of GLP-1 was blocked by luminally-applied exendin-3 (9-39) (100 nM), a GLP-1 receptor antagonist. GLP-1-induced acceleration of peristaltic contractions was also prevented by bath-applied BIBN4069 (1 μM), a CGRP receptor antagonist. In colonic segments that had been exposed to bath-applied capsaicin (100 nM) that desensitizes extrinsic afferents, GLP-1 was still capable of exerting its prokinetic effect. Stimulation of endogenous GLP-1 secretion with a luminally-applied cocktail of short-chain fatty acids (1 mM) increased the frequency of peristaltic waves in an exendin-3 (9-39)-sensitive manner. Thus, GLP-1 activates CGRP-expressing intrinsic afferents to accelerate peristalsis in the proximal colon. Short-chain fatty acids appear to stimulate endogenous GLP-1 secretion from L cells resulting in the acceleration of colonic peristalsis.


Author(s):  
Kenichi Utano ◽  
Koichi Nagata ◽  
Tetsuro Honda ◽  
Takashi Kato ◽  
Alan Kawarai Lefor ◽  
...  

Abstract Purpose CT colonography enables three-dimensional measurement of colon length. However, previous studies using CT colonography have not examined the association with gender, age, physique, a history of laparotomy and bowel habits, all possible contributory factors to colon length. The aim of this study is to investigate factors associated with colon length. Materials and methods We conducted a post hoc analysis based on data obtained from a previous multi-center trial including 321 patients with positive fecal immunochemical tests who underwent CT colonography. Colon length was measured using a computer-generated center line and was divided at the iliac crest level into the distal and proximal colons. Bowel habits were classified into three groups: A—daily; B—once every 2 or 3 days; and C—less than once in 3 days. Statistical comparison was made using one-way ANOVA with Bonferroni’s correction. Results A total of 295 patients were analyzed. The entire colon length (cm, mean ± standard deviation) of individual patients was 150.3 ± 18.5 cm and ranged from 109.7 to 195.9 cm. The female colon was significantly longer than the male colon (154.3 ± 18.1 cm vs. 147.1 ± 18.3 cm; p = 0.022). Colon length showed trends associated with age (p = 0.18) and a history of laparotomy (p = 0.14). According to bowel habits, the entire colon measured 147.4 ± 17.9 in group A, 154.7 ± 18.5 in group B and 158.6 ± 18.3 in group C, and significant differences were observed for “A vs. C” (p = 0.002) and “A vs. B” (p = 0.014). In subgroup analysis by colon segment, the proximal colon trended similarly to the entire colon while there were no trends for the distal colon. Conclusions This study has clearly demonstrated that bowel habits and gender both correlate with the length of the entire colon measured by CT colonography, and in particular, the proximal colon. Secondary abstract Using CT colonography, we measured the colon length in 295 patients. The entire colon length was 150.3 ± 18.5 cm on average. Females and constipated (less frequent defecation) patients have a significantly longer colon, and in particular, the proximal colon. Colon length showed trends associated with age and a history of laparotomy.


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