Distal Colon Research Articles

Nanoencapsulation of Curcuma longa L. extract for the treatment of experimental colitis

Inflammatory bowel diseases (IBDs) are gastrointestinal chronic inflammatory diseases characterized by chronic and recurrent intestinal ulcerations. Curcuminoids are naturally occurring polyphenolic compounds with remarkable bioactivity; however, their low water affinity and bioavailability usually hinder their application. Encapsulation techniques can be coupled with extraction procedures to yield nanoparticles that may have enhanced properties. In this work, curcuminoids were extracted from rhizomes of Curcuma longa L. and simultaneously encapsulated using ultrasound. The characterization of the curcuminoids nanoparticles showed that particles ranging from 124 ± 81 to 252 ± 68 nm were formed, and the main properties of the curcuminoids were maintained after encapsulation. Experimental colitis was induced in rats by 2,4,6-trinitrobenzene sulfonic acid, and they were subsequently treated with 10, 25, or 50 mg kg-1 of nanoencapsulated curcuminoids for 7 days through gavage, during which the disease activity index (DAI) was evaluated. Then the rats were euthanized, and the distal colon was removed for macroscopic analysis and the assessment of the activity of the enzymes myeloperoxidase and N-acetylglucosaminidase. The dose of 25 mg kg-1 of nanoencapsulated curcuminoids reduced the DAI and the activity of inflammatory enzymes compared to the untreated group and was established as the minimum effective dose to be used in the treatment of this model of experimental colitis in rats.

New insight on the enteric cholinergic innervation of the pig colon by central and peripheral nervous systems: reduction by repeated loperamide administration.

The central and peripheral nervous systems provide cholinergic innervation in the colon. The ability to assess their neuroanatomical distinctions is still a challenge. The pig is regarded as a relevant translational model due to the close similarity of its enteric nervous system (ENS) with that of human. Opioid-induced constipation is one of the most common side effects of opioid therapy. We developed an approach to differentiate the central and peripheral cholinergic innervation of the pig colon using double immunolabeling with a novel mouse anti-human peripheral type of choline acetyltransferase (hpChAT) antibody combined with a rabbit anti-common type of ChAT (cChAT) antibody, a reliable marker of cholinergic neurons in the central nervous system. We examined their spatial configurations in 3D images of the ENS generated from CLARITY-cleared colonic segments. The density was quantitated computationally using Imaris 9.7. We assessed changes in the distal colon induced by daily oral treatment for 4 weeks with the μ opioid receptor agonist, loperamide (0.4 or 3 mg/kg). The double labeling showed strong cChAT immunoreactive (ir) fibers in the cervical vagus nerve and neuronal somata and fibers in the ventral horn of the sacral (S2) cord while hpChAT immunoreactivity was visualized only in the ENS but not in the vagus or sacral neural structures indicating the selectivity of these two antibodies. In the colonic myenteric plexus, dense hpChAT-ir neurons and fibers and varicose cChAT-ir fibers surrounding hpChAT-ir neurons were simultaneously visualized in 3D. The density of cChAT-ir varicose fibers in the outer submucosal plexus of both males and females were higher in the transverse and distal colon than in the proximal colon and in the myenteric plexus compared to the outer submucosal plexus and there was no cChAT innervation in the inner submucosal plexus. The density of hpChAT in the ENS showed no segmental or plexus differences in both sexes. Loperamide at the highest dose significantly decreased the density hpChAT-ir fibers + somata in the myenteric plexus of the distal colon. These data showed the distinct density of central cholinergic innervation between myenteric and submucosal plexuses among colonic segments and the localization of cChAT-ir fibers around peripheral hpChAT neurons in 3D. The reduction of cholinergic myenteric innervation by chronic opiate treatment points to target altered prokinetic cholinergic pathway to counteract opiate constipation.

Commensal Escherichia coli Strains of Bovine Origin Competitively Mitigated Escherichia coli O157:H7 in a Gnotobiotic Murine Intestinal Colonization Model with or without Physiological Stress.

Cattle are a primary reservoir of enterohemorrhagic Escherichia coli (EHEC) O157:H7. Currently, there are no effective methods of eliminating this important zoonotic pathogen from cattle, and colonization resistance in relation to EHEC O157:H7 in cattle is poorly understood. We developed a gnotobiotic EHEC O157:H7 murine model to examine aspects of the cattle pathogen-microbiota interaction, and to investigate competitive suppression of EHEC O157:H7 by 18 phylogenetically distinct commensal E. coli strains of bovine origin. As stress has been suggested to influence enteric colonization by EHEC O157:H7 in cattle, corticosterone administration (±) to incite a physiological stress response was included as an experimental variable. Colonization of the intestinal tract (IT) of mice by the bovine EHEC O157:H7 strain, FRIK-2001, mimicked characteristics of bovine IT colonization. In this regard, FRIK-2001 successfully colonized the IT and temporally incited minimal impacts on the host relative to other EHEC O157:H7 strains, including on the renal metabolome. The presence of the commensal E. coli strains decreased EHEC O157:H7 densities in the cecum, proximal colon, and distal colon. Moreover, histopathologic changes and inflammation markers were reduced in the distal colon of mice inoculated with commensal E. coli strains (both propagated separately and communally). Although stress induction affected the behavior of mice, it did not influence EHEC O157:H7 densities or disease. These findings support the use of a gnotobiotic murine model of enteric bovine EHEC O157:H7 colonization to better understand pathogen-host-microbiota interactions toward the development of effective on-farm mitigations for EHEC O157:H7 in cattle, including the identification of bacteria capable of competitively colonizing the IT.

Disinfection by-products in drinking water and risk of colorectal cancer: a population-based cohort study.

Colorectal cancer is the third most common malignancy worldwide and is strongly linked to lifestyle and environmental risk factors. Although several drinking-water disinfection by-products are confirmed rodent carcinogens, the evidence in humans for carcinogenicity associated with these by-products, including colorectal cancer, is still inconclusive. We assessed the association of long-term exposure to trihalomethanes (THMs), the most prevalent disinfection by-products in chlorinated drinking water, with incidence of colorectal cancer in 58 672 men and women in 2 population-based cohorts. Exposure was assessed by combining long-term information of residential history with drinking water-monitoring data. Participants were categorized according to no exposure, low exposure (<15µg/L), and high exposure (≥15µg/L). Incident cases of colorectal cancer were ascertained by use of the Swedish National Cancer Register. During an average follow-up of 16.8years (988 144 person-years), 1913 cases of colorectal cancer were ascertained (1176 cases in men and 746 in women, respectively). High THM concentrations in drinking water (≥15 µg/L) were associated with increased risk of colorectal cancer in men (hazard ratio = 1.26, 95% confidence interval = 1.05-1.51) compared with no exposure. When subsites were assessed, the association was statistically significant for proximal colon cancer (hazard ratio = 1.59, 95% confidence interval = 1.11 to 2.27) but not for distal colon cancer or rectal cancer. In women, we observed overall no association of THMs with colorectal cancer. These results add further evidence that disinfection by-products in drinking water may be a possible risk factor for proximal colon cancer in men. This observation was made at THM concentrations lower than those in most previous studies.

A Gradient of Intestinal Inflammation in Primary Sclerosing Cholangitis.

Primary sclerosing cholangitis (PSC) is a progressive liver disease associated with inflammatory bowel disease (IBD). The percentage of PSC patients diagnosed with concomitant IBD varies considerably between studies. This raises the question whether all PSC patients would show intestinal inflammation if screened thoroughly, even in the absence of symptoms. To address this question, we collected intestinal biopsies of healthy controls (n = 34), PSC (n = 25), PSC-IBD (n = 41), and IBD (n = 51) patients in a cross-sectional study and carried out cytokine expression profiling, 16S sequencing, in-depth histology, and endoscopy scoring. We found that the vast majority of PSC patients even without clinically manifest IBD showed infiltration of immune cells and increased expression of IL17A and IFNG in intestinal biopsies. However, expression of IL10 and FOXP3 were likewise increased, which may explain why these PSC patients have intestinal inflammation only on a molecular level. This subclinical inflammation in PSC patients was focused in the distal colon, whereas PSC-IBD patients showed inflammation either at the distal colon or on the right side of the colon and the terminal ileum. Furthermore, we observed that PSC patients without IBD showed signs of dysbiosis and exhibited a distinct microbial profile compared with healthy controls. We found a gradient of intestinal inflammation in the vast majority of PSC patients even in the absence of IBD. Thus, further studies evaluating the effect of anti-inflammatory therapies in PSC patients and their impact on the emergence of clinically manifest IBD and colorectal cancer development are needed.

Anatomical location, risk factors, and outcomes of lower gastrointestinal bleeding in colorectal cancer patients: a national inpatient sample analysis (2009-2019).

This study aimed to investigate the incidence, predictors, and impact of lower gastrointestinal bleeding (LGIB) on inpatient mortality among colorectal cancer patients, due to its clinical significance and potential influence on patient outcomes. We conducted a retrospective analysis of data from the National Inpatient Sample database between 2009 and 2019, including 2,598,326 colorectal cancer patients with and without LGIB. Univariate and multivariate logistic regression analyses were performed to determine predictors of LGIB and its association with inpatient outcomes. The highest incidence of LGIB was observed in rectal cancer patients (3.8%), followed by distal colon cancer patients (1.4%) and proximal colon cancer patients (1.2%). Several factors were significantly associated with LGIB, including older age; male sex; certain racial such as Black, Hispanic, and Asia/Pacific Islander patients; or lower socioeconomic status. Multivariate analysis identified independent predictors of LGIB, such as severe sepsis, use of anticoagulants, long-term use of aspirin or antiplatelet drugs, palliative care, malnutrition, cachexia, chemotherapy or immunotherapy, metastasis, alcohol abuse, hypertension, obesity, and family history of digestive cancer. No significant difference in inpatient mortality was observed between patients with and without LGIB. Our study underscores the importance of considering colorectal cancer location and identified risk factors for LGIB assessment. Clinicians should address modifiable risk factors and healthcare disparities. Future research should explore underlying mechanisms, targeted interventions, and long-term outcomes beyond inpatient mortality.

Clinical and endoscopic characteristics and management of 220 cases with serrated polyps

BackgroundSerrated polyps are considered the precursor lesions of colorectal cancer through the serrated pathway. In the present study, we aimed to evaluate and discuss the clinical and endoscopic characteristics and management of serrated polyps. MethodsThe data of 220 cases with serrated polyps between September 2018 and November 2021 in Shenzhen People's Hospital were retrospectively analyzed. ResultsOf all these cases, 32 were hyperplastic polyps, 36 were traditional serrated adenomas, 126 were sessile serrated lesions, 25 were SSLs with dysplasia, and one was an unclassified serrated adenoma. Although most patients were males aged ≥50 years and most serrated polyps were located in the distal colon and rectum with a size of 6–10 mm and the shape of type 0-Is, there was no significant difference (P > 0.05). Serrated polyps of ≤5 mm in size and type 0-IIa were mostly removed by cold biopsy forceps. Cold snare polypectomy was primarily used for those of 6–10 mm in size. Endoscopic mucosal resection was used for those of 6–20 mm, and endoscopic submucosal dissection was used for those of ≥20 mm (P < 0.05). All complications occurred in SSL patients with or without dysplasia (P < 0.05). ConclusionsClinical and endoscopic characteristics were beneficial for distinguishing and diagnosing serrated polyps. In addition, management options were crucial to prevent recurrence and progression. However, the detection rate of serrated polyps was relatively low. Therefore, prospective multicenter studies with large samples are necessary to better assess colorectal serrated polyps.

Expression of Cyclooxygenase-2 in Patients With Snow-White Sign of Advanced Colorectal Adenomas

Objective To analyze the expression of cyclooxygenase-2 (COX-2) in the patients with snow-white sign of advanced colorectal adenoma (ACA) and explore its clinical significance.Method Western blotting was employed to determine the expression of COX-2 in the adenoma tissue and the normal tissue adjacent to the adenoma tissue (>5 cm away from the distal end of the adenoma tissue) of 40 ACA patients with snow-white sign and 40 ACA patients without snow-white sign.Results The appearance of snow-white sign in ACA patients was associated with patient age (P=0.001) and not associated with sex,smoking history,drinking history,ethnic groups,family history of colorectal cancer,abdominal pain,diarrhea,constipation,fecal occult blood,or tumor markers (all P>0.05).Snow-white sign mainly appeared in the ACA patients with multiple adenomas (P=0.004),large adenomas (P=0.006),adenomas in distal colon (P=0.015),protruding polyps (P=0.044),and late-stage pathology (P=0.010).The occurrence of snow-white sign showed no difference in the ACA patients with different results of Japan NBI Expert Team classification (P=0.502).The expression of COX-2 in the adenoma tissue was higher than that in the adjacent normal tissue in the patients with and without snow-white sign (P<0.001,P=0.004).The patients with snow-white sign had higher expression of COX-2 protein in the adenoma tissue than the patients without snow-white sign (P=0.001).The expression of COX-2 protein in the adjacent healthy tissue had no significant difference between the patients with and without snow-white sign (P=0.603).Conclusions Snow-white sign is more like to appear in the ACA patients with young age,multiple and large adenomas,adenomas in distal colon,protruding polyps,and late-stage pathology.Moreover,the expression of COX-2 in the ACA patients with snow-white sign is significantly higher than that in the ACA patients without snow-white sign.The adults with snow-white sign are prone to cancerization than those without snow-white sign.

DRG afferents that mediate physiologic and pathologic mechanosensation from the distal colon

The properties of dorsal root ganglia (DRG) neurons that innervate the distal colon are poorly defined, hindering our understanding of their roles in normal physiology and gastrointestinal (GI) disease. Here, we report genetically defined subsets of colon-innervating DRG neurons with diverse morphologic and physiologic properties. Four colon-innervating DRG neuron populations are mechanosensitive and exhibit distinct force thresholds to colon distension. The highest threshold population, selectively labeled using Bmpr1b genetic tools, is necessary and sufficient for behavioral responses to high colon distension, which is partly mediated by the mechanosensory ion channel Piezo2. This Aδ-HTMR population mediates behavioral over-reactivity to colon distension caused by inflammation in a model of inflammatory bowel disease. Thus, like cutaneous DRG mechanoreceptor populations, colon-innervating mechanoreceptors exhibit distinct anatomical and physiological properties and tile force threshold space, and genetically defined colon-innervating HTMRs mediate pathophysiological responses to colon distension, revealing a target population for therapeutic intervention.

Pathogenic roles of microRNAs and competing endogenous RNAs in Hirschsprung disease (HSCR): Potential diagnostic markers for HSCR

AbstractMicroRNAs (miRNAs) are endogenous small non‐coding single‐stranded RNAs. They can bind to the 3′‐untranslated region (3′UTR) of mRNAs and regulate the expression of their target genes by inducing degradation or translation inhibition of the corresponding mRNAs. Competing endogenous RNAs (ceRNAs) can disable miRNAs by combining miRNAs response elements (MREs) with miRNAs. Hirschsprung disease (HSCR) is a common pediatric surgical disease in which cells derived from the enteric neural crest fail to colonize the distal colon, but its pathogenesis is not very clear. In recent years, with more and more studies on miRNAs in HSCR, miRNAs seem to be involved in the pathogenesis of HSCR. miRNAs in HSCR affect the proliferation and migration of enteric neural crest cells mainly through target genes, and ceRNAs inhibit miRNAs, thus participating in the pathogenesis of HSCR. It was reported that some miRNAs in the serum of children with HSCR were significantly higher than those in the control group. Therefore, miRNAs are expected to be a new noninvasive early screening biomarker and targeted therapy point for HSCR. Here, we provide a summary of the understanding of miRNAs and ceRNAs in regulating enteric nervous system proliferation and migration and their roles in the pathogenesis of HSCR.

The lncRNA HOXA11os regulates mitochondrial function in myeloid cells to maintain intestinal homeostasis

This study reveals a previously uncharacterized mechanism to restrict intestinal inflammation via a regulatory RNA transcribed from a noncoding genomic locus. We identified a novel transcript of the lncRNA HOXA11os specifically expressed in the distal colon that is reduced to undetectable levels in colitis. HOXA11os is localized to mitochondria under basal conditions and interacts with a core subunit of complex 1 of the electron transport chain (ETC) to maintain its activity. Deficiency of HOXA11os in colonic myeloid cells results in complex I deficiency, dysfunctional oxidative phosphorylation (OXPHOS), and the production of mitochondrial reactive oxygen species (mtROS). As a result, HOXA11os-deficient mice develop spontaneous intestinal inflammation and are hypersusceptible to colitis. Collectively, these studies identify a new regulatory axis whereby a lncRNA maintains intestinal homeostasis and restricts inflammation in the colon through the regulation of complex I activity.

Plasticity of colonic enteric nervous system following spinal cord injury in male and female rats.

Neurogenic bowel is a dysmotility disorder following spinal cord injury (SCI) that negatively impacts quality of life, social integration, and physical health. Colonic transit is directly modulated by the enteric nervous system. Interstitial Cells of Cajal (ICC) distributed throughout the small intestine and colon serve as specialized pacemaker cells, generating rhythmic electrical slow waves within intestinal smooth muscle, or serve as an interface between smooth muscle cells and enteric motor neurons of the myenteric plexus. Interstitial Cells of Cajal loss has been reported for other preclinical models of dysmotility, and our previous experimental SCI study provided evidence of reduced excitatory and inhibitory enteric neuronal count and smooth muscle neural control. Immunohistochemistry for the ICC-specific marker c-Kit was utilized to examine neuromuscular remodeling of the distal colon in male and female rats with experimental SCI. Myenteric plexus ICC (ICC-MP) exhibited increased cell counts 3 days following SCI in male rats, but did not significantly increase in females until 3 weeks after SCI. On average, ICC-MP total primary arborization length increased significantly in male rats at 3-day, 3-week, and 6-week time points, whereas in females, this increase occurred most frequently at 6 weeks post-SCI. Conversely, circular muscle ICC (ICC-CM) did not demonstrate post-SCI changes. These data demonstrate resiliency of the ICC-MP in neurogenic bowel following SCI, unlike seen in other related disease states. This plasticity underscores the need to further understand neuromuscular changes driving colonic dysmotility after SCI in order to advance therapeutic targets for neurogenic bowel treatment.

Decaying kidney function during cirrhosis correlates with remodeling of distal colon aldosterone target gene expression.

Liver cirrhosis is associated to circulatory abnormalities leading to hypovolemia and stimulation of the renin-angiotensin-aldosterone system (RAAS). Advanced stages of the disease cause renal failure, impairing K+ and Na+ homeostasis. It has been proposed that the distal colon undergoes functional remodeling during renal failure, in particular by aldosterone-driven increased K+ excretion. In this study, we compared the transcriptional response of aldosterone target genes in the rat distal colon under two models of increased circulating aldosterone (one with concomitant RAAS activation) and in a model of secondary hyperaldosteronism induced by cirrhosis. The expression of a subset of these genes was also tested in distal colon biopsies from control subjects or patients with cirrhosis with varying levels of disease progression and treated or not with mineralocorticoid receptor inhibitor spironolactone. We examined known aldosterone-regulated transcripts involved in corticosteroid signaling and transepithelial ion transport. In addition, we included aldosterone-regulated genes related to cell proliferation. Our comparison revealed multiple aldosterone target genes upregulated in the rat distal colon during decompensated cirrhosis. Epithelial Na+ channel β and γ subunit expression correlated positively with plasma aldosterone concentration and negatively with glomerular filtration rate. Patients with cirrhosis showed increased expression of 11-β-hydroxysteroid-dehydrogenase 2 (11βHSD2), which was reverted by spironolactone treatment, suggesting a sensitization of the distal colon to aldosterone action. In summary, our data show that decaying kidney function during cirrhosis progression toward a decompensated state with hypovolemia correlates with remodeling of distal colon ion transporter expression, supporting a role for aldosterone in the process.NEW & NOTEWORTHY Liver cirrhosis progression significantly alters ion transporter subunit expression in the rat distal colon, a change that correlated well with declining kidney function and the severity of the disease. Our data suggest that the steroid hormone aldosterone participates in this homeostatic response to maintain electrolyte balance.

2'-fucosyllactose alone or combined with resistant starch increases circulating short-chain fatty acids in lean men and men with prediabetes and obesity.

Infusion of short-chain fatty acids (SCFA) to the distal colon beneficially affects human substrate and energy metabolism. Here, we hypothesized that the combination of 2'-fucosyllactose (2'-FL) with resistant starch (RS) increases distal colonic SCFA production and improves metabolic parameters. In this randomized, crossover study, 10 lean (BMI 20-24.9 kg/m2) and nine men with prediabetes and overweight/obesity (BMI 25-35 kg/m2) were supplemented with either 2'-FL, 2'-FL+RS, or placebo one day before a clinical investigation day (CID). During the CID, blood samples were collected after a overnight fast and after intake of a liquid high-fat mixed meal to determine plasma SCFA (primary outcomes). Secondary outcomes were fasting and postprandial plasma insulin, glucose, free fatty acid (FFA), glucagon-like peptide-1, and peptide YY concentrations. In addition, fecal SCFA and microbiota composition, energy expenditure and substrate oxidation (indirect calorimetry), and breath hydrogen excretion were determined. In lean men, supplementation with 2'-FL increased postprandial plasma acetate (P = 0.017) and fasting H2 excretion (P = 0.041) compared to placebo. Postprandial plasma butyrate concentration increased after 2'-FL and 2'-FL+RS as compared to placebo (P < 0.05) in lean men and men with prediabetes and overweight/obesity. Additionally, 2'-FL+RS decreased fasting and postprandial plasma FFA concentrations compared to placebo (P < 0.05) in lean men. Supplementation of 2'-FL with/without RS the day before investigation increased systemic butyrate concentrations in lean men as well as in men with prediabetes and obesity, while acetate only increased in lean men. The combination of 2'-FL with RS showed a putatively beneficial metabolic effect by lowering plasma FFA in lean men, indicating a phenotype-specific effect. nr. NCT04795804.

Establishment and identification of an animal model of Hirschsprung disease in suckling mice

BackgroundHirschsprung disease (HSCR) is a congenital intestinal malformation. Previous HSCR animal model needs invasive operation on adult animal. The aim of this study is to establish an early-onset animal model which is consistent with the clinical manifestation of HSCR patients.MethodsThe neonatal mice were randomly divided into the benzalkonium chloride (BAC) group, treated with BAC via enema, and the control group, treated with saline. Weight changes, excretion time of carmine, CT scan, hematoxylin-eosin staining and immunofluorescence staining were used to evaluate the effect of the model. Differentially expressed genes (DEGs) in the HSCR mice were analyzed by using DAVID 6.8 database and compared with DEGs from HSCR patients.ResultsThe weight of mice was lower and the excretion time of carmine was longer in the BAC group. Moreover, distal colon stenosis and proximal colon enlargement appeared in the BAC group. Neurons in the distal colon decreased significantly after 4 weeks of BAC treatment and almost disappeared completely after 12 weeks. Transcriptome profiling of the mouse model and HSCR patients is similar in terms of altered gene expression.ConclusionsAn economical and reliable HSCR animal model which has similar clinical characteristics to HSCR patients was successfully established.ImpactThe animal model of Hirschsprung disease was first established in BALB/c mice.This model is an animal model of early-onset HSCR that is easy to operate and consistent with clinical manifestations.Transcriptome profiling of the mouse model and HSCR patients is similar in terms of altered gene expression.

Association of sugar-sweetened beverages with the risk of colorectal cancer: a systematic review and meta-analysis.

The association between sugar-sweetened beverages intake and colorectal cancer (CRC) remains controversial. A metaanalysis was performed to clarify the correlation between sugar-sweetened beverages and CRC risk/mortality. A systematic literature search was conducted in PubMed, Web of Science, Embase, China National Knowledge Infrastructure (CNKI), Sinomed (CBM), Wanfang Data Knowledge Service Platform, and China Science and Technology Journal VIP database. Articles were restricted to be available in any language until March 31, 2022. The highest exposed categories were used to calculate the pooled relative risks (RR) values. Pooled relative risks (RR) and 95% confidence intervals (CI) were used to estimate the association of sugar-sweetened beverages with CRC risk and mortality. Heterogeneity was assessed with the Cochran Q statistic and quantified with the I2 statistic. A total of 17 studies (6 case-control and 11 cohort) involving 557,391 subjects were included in this meta-analysis. The pooled RRs for CRC incidence and mortality among people taking sugar-sweetened beverages were 1.17 (95% CI: 1.07-1.28) and 1.13 (95% CI: 0.99-1.29), respectively. In subgroup analysis, a correlation was found in the distal colon with a pooled RR of 1.41 (95% CI: 1.10-1.80). There was no correlation in the proximal colon with a pooled RR of 1.58 (95% CI: 0.79-3.17). We found statistically significant associations between CRC incidence and sugar-sweetened beverages intake in North America and Oceania, with pooled RRs of 1.16 (95% CI: 1.00-1.33) and 1.32 (95% CI: 1.13-1.55), respectively. In sensitivity analysis, after excluding each study and calculating heterogeneity and effect sizes, there was still a correlation between sugar-sweetened beverages intake and CRC risk. This meta-analysis suggests that sugar-sweetened beverages intake may increase CRC risk, independent of CRC mortality. Whether CRC risk increases with increased sugar-sweetened beverage intake needs further investigation in the future. This meta-analysis aimed to indicate the relationship between sugar-sweetened beverages intake and the risk and mortality of colorectal cancer. A total of 17 studies involving 557,391 subjects were included. The results showed that sugar-sweetened beverages may increase the risk of colorectal cancer but may not be associated with colorectal cancer mortality.

Quantitative differences in synthetic gut microbial inoculums do not affect the final stabilized in vitro community compositions.

In vitro studies of synthetic gut microbial communities (SGMCs) can provide valuable insights into the ecological structure and function of gut microbiota. However, the importance of the quantitative composition of an SGMC inoculum and its effect on the eventual stable in vitro microbial community has not been studied. To address this, we constructed two 114-member SGMCs differing only in their quantitative composition-one reflecting the average human fecal microbiome and another mixed in equal proportions based on cell counts. We inoculated each in an automated anaerobic multi-stage in vitro gut fermentor simulating two different colonic conditions, mimicking proximal and distal colons. We replicated this setup with two different nutrient media, periodically sampled the cultures for 27 days, and profiled their microbiome compositions using 16S rRNA gene amplicon sequencing. While nutrient medium explained 36% of the variance in microbiome composition, initial inoculum composition failed to show a statistically significant effect. Under all four conditions, paired fecal and equal SGMC inoculums converged to reach stable community compositions resembling each other. Our results have broad implications for simplifying in vitro SGMC investigations. IMPORTANCE In vitro cultivation of synthetic gut microbial communities (SGMCs) can provide valuable insights into the ecological structure and function of gut microbiota. However, it is currently not known whether the quantitative composition of the initial inoculum can influence the eventual stable in vitro community structure. Hence, using two SGMC inoculums consisting of 114 unique species mixed in either equal proportions (Eq inoculum) or resembling proportions in an average human fecal microbiome (Fec inoculum), we show that initial inoculum compositions did not influence the final stable community structure in a multi-stage in vitro gut fermentor. Under two different nutrient media and two different colon conditions (proximal and distal), both Fec and Eq communities converged to resemble each other's community structure. Our results suggest that the time-consuming preparation of SGMC inoculums may not be needed and has broad implications for in vitro SGMC studies.

Adult-onset megacolon with focal hypoganglionosis: A detailed phenotyping and prospective cohort study.

In this prospective cohort study, we evaluated features of "adult-onset megacolon with focal hypoganglionosis." We assessed the radiologic, endoscopic, and histopathologic phenotyping and treatment outcomes of 29 patients between 2017 and 2020. Data from community controls, consisting of 19,948 adults undergoing health screenings, were analyzed to identify risk factors. Experts reviewed clinical features and pathological specimens according to the London Classification for gastrointestinal neuromuscular pathology. The median age of the patients with adult-onset megacolon with focal hypoganglionosis at symptom onset was 59 years (range, 32.0-74.9 years), with mean symptom onset only 1 year before diagnosis. All patients had focal stenotic regions with proximal bowel dilatation (mean diameter, 78.8 mm; 95% confidence interval [CI], 72-86). The comparison with community controls showed no obvious risk factors. Ten patients underwent surgery, and all exhibited significant hypoganglionosis: 5.4 myenteric ganglion cells/cm (interquartile range [IQR], 3.7-16.4) in the stenotic regions compared to 278 cells/cm (IQR, 190-338) in the proximal and 95 cells/cm (IQR, 45-213) in the distal colon. Hypoganglionosis was associated with CD3+ T cells along the myenteric plexus. Colectomy was associated with significant symptom improvement compared to medical treatment [change in the Global Bowel Satisfaction score, -5.4 points (surgery) vs. -0.3 points (medical treatment); p < 0.001]. Adult-onset megacolon with focal hypoganglionosis has distinct features characterized by hypoganglionosis due to inflammation. Bowel resection appears to benefit these patients.

Increasing dietary nutrient levels modulates colon immune adaptation and alleviates inflammation in the epithelial heterogeneous nuclear ribonucleoprotein I (Hnrnp I) knockout mice

Heterogeneous nuclear ribonucleoprotein I (HNRNP I) is an RNA-binding protein essential for neonatal immune adaptation by downregulating interleukin-1 receptor-associated kinase (IRAK1) in toll-like receptor (TLR)-mediated NF-κB signaling pathways. TLR-mediated NF-κB is associated with chronic inflammation, including the development of inflammatory bowel diseases. Meanwhile, dietary protein intake is one of the major concerns for individuals with inflammatory bowel diseases. The present study aims to investigate the effects of a protein-enriched diet on intestinal inflammation and immune responses in a mouse model with aberrant NF-κB signaling in the colon. A transgenic mouse model with intestinal-epithelial-cell (IEC) specific Hnrnp I knocked out was used to investigate the effects of protein intake on the immune system in the colon. A control diet (CON) and a nutrient-dense modified diet (MOD) were fed to both the wild-type (WT) and the knockout (KO) male mice for 14 weeks. Inflammatory markers and colonic immune responses were examined, with gene expression and protein expression levels analyzed. IEC-specific Hnrnp I knocked out mice had significantly increased expression of the active NF-κB subunit, P65, in their colons. There was a concomitant induction of mRNA expression of Il1β, Il6, Cxcl1, and Ccl2. The number of CD4+ T cells in the distal colon was also increased in the KO mice. The results confirmed that KO mice had proinflammatory responses with aberrant NF-κB signaling in the colon. Importantly, increased nutrient density in their diets attenuated colon inflammation by decreasing the expression of proinflammatory cytokines, reducing P65 translocation, downregulating IRAK1, and limiting the number of CD4+ T cells recruited in Hnrnp I KO mice colon. In summary, this study found that a diet with increased nutrient density relieved the inflammation induced by knockout of Hnrnp I, attributable partially to the reduced expression of inflammatory and immune-modulating cytokines in the mouse distal colon.

The Effect of Lunasin on Inhibition of KI67, BCL-2 and C-MYC Expression in Azoxymethane and Dextran Sodium Sulfate Induced Mice Colon

Treatment of cancer using medicinal-plant based has been important due to minimal side effects, high efficiency and low cost. Lunasin from soybean is known as potential chemopreventive agent. This study aimed to study and investigate the proteins involved in the mechanisms of action of lunasin underlie its chemopreventive effects in Azoxymethane (AOM) and Dextran Sodium Sulfate (DSS) induced mice. A total 30 BLAB/c mice were separated into six groups. In five of the groups - a negative control group, positive control group, and three intervention groups - carcinogenesis was induced with AOM and DSS; the sixth group received no interventions. Lunasin were given in different doses of Low Dose Lunasin (75 mg/kgBW), Moderate Dose Lunasin (150 mg/kgBW), and High Dose Lunasin (200 mg/kgBW) to intervention groups. Immunohistochemistry was conducted to measure Ki67, C-myc, and Bcl-2 expressions from the distal colons of mice that had been sacrificed. The samples were microscopically assessed and photographed, and cell counts were performed using the Image J application. Further, the H-score method was used to quantify of Ki67, C-myc and Bcl-2 expressions. The results of this show that there is significant differences between the negative control and the intervention groups were found at the 75 mg/kgBW and 150 mg/kgBW (p &lt; 0.05) lunasin dosage levels. This demonstrates that Lunasin inhibits proliferation and induces apoptosis in the colon mice induced by AOM and DSS.