Search Results (182)

Background: Circadian disruption (CD) aggravates metabolic dysfunction-associated steatohepatitis (MASH), but supplementation with prebiotics inulin and oat β-glucan may mitigate its effects. However, their impact on colonic architecture and hepatic proteome remains unclear. Objectives: We aimed to investigate the effects of prebiotics inulin and oat β-glucan on colonic architecture and hepatic proteome in mice with CD-aggravated MASH. Methods: CD was induced by weekly reversal of the light–dark cycle to simulate shift work. Male C57BL/6J mice were subjected to non-shifted chow, non-shifted fructose, palmitate, cholesterol, and trans-fat (FPC) diet, shifted chow, or shifted FPC diet (SFPC) for 26 weeks. Prebiotics inulin and oat β-glucan supplementation were provided to the SFPC group in the final 10 weeks. Distal colon and serum samples were collected for histological examination and endotoxemia evaluation, respectively. Liver samples were collected for proteomic mass spectrometry analysis. Results: Mice with CD-aggravated MASH were found with colonic crypt loss and a distinct hepatic proteome structure compared to mice with non-CD MASH. Notably, inulin showed better effects than oat β-glucan in preserving colonic crypts in mice with CD-aggravated MASH. Furthermore, inulin supplementation restored the hepatic proteome structure similar to that of non-CD MASH mice, a benefit not observed with oat β-glucan. Conclusions: Given our prior findings showing oat β-glucan’s superior ability to enrich gut bacterial species associated with MASH improvement under CD, this study highlights inulin’s unique benefits for colonic architecture and hepatic proteome regulation in CD-aggravated MASH. Full article

Enterotoxigenic Bacteroides fragilis (ETBF) promotes colitis-associated cancer through the Bacteroides fragilis toxin (BFT), which induces colonic inflammation that can be exacerbated by external stimuli. We found that BALB/c mice infected with ETBF and treated with azoxymethane and dextran sodium sulfate (DSS) developed numerous distal colon polyps more rapidly than B6 mice, suggesting strain differences in ETBF-induced tumorigenicity. Using a bft gene-deficient ETBF strain, we confirmed BFT’s crucial role in ETBF-promoted tumorigenesis and inflammation. While both 1% and 2% DSS induced comparable polyp formation, 1% DSS minimized mortality, proving sufficient for maximizing polyp development. Mechanistically, BFT-mediated tumorigenesis involves NF-κB/CXCL1 signaling in colonic epithelial cells exposed to BFT and DSS, a pathway known to be critical for inflammation and cancer progression. This model provides a valuable platform for dissecting ETBF’s colitis-associated cancer-promoting mechanisms, particularly those involving BFT, and for evaluating BFT-targeted therapeutic interventions. Full article

Aquaporin 1 is a membrane water channel protein, which was studied here in spiny dogfish (Squalus acanthias) osmoregulatory tissues using a variety of techniques. The cloning of aquaporin 1 (AQP1) in the spiny dogfish identified a splice variant version of the mRNA/protein (AQP1SV1/AQP1SV1). Polymerase chain reaction (PCR) in a range of tissues showed AQP1 to be expressed at very high levels in the rectal gland with ubiquitous mRNA expression at lower levels in other tissues. Northern blotting showed that AQP1 had a mRNA size of 5.3 kb in kidney total RNA. The level of AQP1 mRNA was significantly lower in the rectal glands of fish acclimated to 120% seawater (SW; vs. 75% SW (p = 0.0007) and 100% SW (p = 0.0025)) but was significantly higher in those fish in the kidney (vs. 100% SW (p = 0.0178)) and intestine (vs. 75% SW (p= 0.0355) and 100% SW (p = 0.0285)). Quantitative PCR determined that AQP1SV1 mRNA levels were also significantly lower in the rectal glands of both 120% (p = 0.0134) and 100% SW (p = 0.0343) fish in comparison to 75% SW-acclimated dogfish. Functional expression in Xenopus oocytes showed that AQP1 exhibited significant apparent membrane water permeability (p = 0.000008–0.0158) across a range of pH values, whereas AQP1SV1 showed no similar permeability. Polyclonal antibodies produced against AQP1 (AQP1 and AQP1/2 antibodies) and AQP1SV1 had bands at the expected sizes of 28 kDa and 24 kDa, respectively, as well as some other banding. The weak AQP1 antibody and the stronger AQP1/2 antibody exhibited staining in the apical membranes of rectal gland secretory tubules, particularly towards the periphery of the gland. In the gill, the AQP1/2 antibody in particular showed staining in secondary-lamellar pavement-cell basal membranes, and in blood vessels and connective tissue in the gill arch. In the spiral valve intestine side wall and valve flap, the AQP1/2 antibody stained muscle tissue and blood vessel walls and, after tyramide signal amplification, showed some staining in the apical membranes of epithelial cells at the ends of the luminal surface of epithelial folds. In the rectum/colon, there was also some muscle and blood vessel staining, but the AQP1 and AQP1/2 antibodies both stained a layer of cells at the base of the surface epithelium. In the kidney convoluted bundle zone, all three antibodies stained bundle sheath membranes to variable extents, and the AQP1/2 antibody also showed staining in the straight bundle zone bundle sheath. In the kidney sinus zone, the AQP1/2 antibody stained the apical membranes of late distal tubule (LDT) nephron loop cells most strongly, with the strongest staining in the middle of the LDT loop and in patches towards the start of the LDT loop. There was also a somewhat less strong staining of segments of the first sinus zone nephron loop, particularly in the intermediate I (IS-I) tubule segment. Some tubules appeared to show no or only low levels of staining. The results suggest that AQP1 plays a role in rectal gland fluid secretion, kidney fluid reabsorption and gill pavement-cell volume regulation and probably a minor role in intestinal/rectal/colon fluid absorption. Full article

Background/Objectives: Inflammatory bowel disease (IBD), encompassing Crohn’s disease and ulcerative colitis, is characterized by cycles of inflammation and tissue remodeling that can culminate in fibrosis. Differentiating between early inflammatory and fibrotic bowel wall changes remains a diagnostic challenge due to overlapping imaging features. This study aimed to assess the potential of elastography, specifically pixel histogram analysis, as a non-invasive method to identify acute inflammatory changes in a rat model of 2,4,6-trinitrobenzenesulfonic (TNBS)-induced colitis. Methods: Female CRL:Wi rats were randomized into control and experimental groups, with the latter receiving intracolonic TNBS to induce acute colitis. On day 7 post-induction, all animals underwent ultrasonographic and strain elastographic assessment of the distal colon using a standardized protocol. Histogram-based analysis of red, green, and blue pixel distributions was performed on elastographic video frames. Results were compared with histologic grading of inflammation and fibrosis using hematoxylin-eosin and Masson’s trichrome staining. Results: Rats with TNBS-induced colitis exhibited significant weight loss, increased bowel wall thickness (31.5% vs. controls, p < 0.01), and elevated elastographic pixel intensity across all color channels (p < 0.05). Histologically, experimental animals showed severe inflammation and early submucosal fibrosis. A strong positive correlation was found between elastographic histogram values and histologic fibrosis scores (r = 0.86, p < 0.01), confirming the technique’s diagnostic relevance. Conclusions: Elastographic pixel histogram analysis is a reproducible, non-invasive approach capable of distinguishing acute inflammatory changes and early fibrotic remodeling in experimental colitis. These findings support its potential application as a diagnostic adjunct in the early assessment and monitoring of IBD-related bowel wall changes. Full article

Fucoidans have demonstrated a wide range of bioactivities including immune modulation and benefits in gut health. To gain a deeper understanding on the effects of fucoidan from Undaria pinnatifida (UPF) on the colonic microbiome, the short-term Simulator of the Human Intestinal Microbial Ecosystem^®, a validated in vitro gut model, was applied. Following a three-week intervention period on adult faecal samples from three healthy donors, microbial community activity of the colonic microbiota was assessed by quantifying short-chain fatty acids while composition was analysed utilising 16S-targeted Illumina sequencing. Metagenomic data were used to describe changes in community structure. To assess the secretion of cytokines, co-culture experiments using Caco-2 and THP1-Blue™ cells were performed. UPF supplementation over a three-week period had a profound butyrogenic effect while also enriching colonic microbial diversity, consistently stimulating saccharolytic genera, and reducing genera linked with potentially negative health effects in both regions of the colon. Mild immune modulatory effects of UPF were also observed. Colonic fermentation of UPF showed anti-inflammatory properties by inducing the secretion of the anti-inflammatory cytokines IL-6 and IL-10 in two out of three donors in the proximal and distal colon. In conclusion, UPF supplementation may provide significant gut health benefits. Full article

Drosophila subobscura is a Palearctic species that colonized the west coast of South and North America in the last quarter of the 20th century. This species stands out for its large chromosomal inversion polymorphism that affects its five long chromosomes. Studies of natural populations revealed that the inversion polymorphism has an adaptive character and while the arrangement U_st was classified as adapted to cold, other arrangements, such as U₁₊₂₊₆ and U₁₊₈₊₂, were considered warm adapted. Characterization of the inversion breakpoints will allow a first approach to the genes included in the inversions and to find candidates to be affected by selection. In this work, we take advantage of the existence of a reference genomic sequence carrying the U₁₊₂ arrangement to locate the breakpoints of the U₆ and U₈ inversions, mapping paired-end Illumina reads from two homokaryotypic strains to U₁₊₂₊₆ and U₁₊₈₊₂, respectively. To date, most of the characterized inversion breakpoints in D. subobscura have been generated by non-homologous end-joining. In contrast, the U₆ and U₈ inversions seem to have originated by transposons, and, at the distal breakpoint of inversion U₈, we describe a new fold-back-like element characteristic of the suboscura species group that we have named Ziga-Zaga. Full article

Ulcerative colitis (UC) is the most prevalent inflammatory bowel disease (IBD) in the USA. Current treatments present clinical limitations, underscoring the need for innovative therapeutics that promote an anti-inflammatory immune response. This study evaluates the anti-inflammatory potential of Fh15, a recombinant Fasciola hepatica fatty acid binding protein, in a DSS-induced UC mouse model. Our results demonstrated that Fh15 treatment significantly ameliorated the severity of colitis by reducing the disease activity index (DAI) and histopathological scores. Moreover, Fh15 also decreased the serum levels of myeloperoxidase (MPO) and chitinase-3-like protein 1 (CHI3L1), and the expression of S100A9, a calcium and zinc binding protein, which is an important marker for the pathogenesis of UC. Furthermore, Fh15 downregulated pro-inflammatory cytokines TNFα and IL-1β in the distal colon, suggesting modulation of macrophage activity. Immunohistochemistry analysis revealed significantly reduced neutrophil and macrophage infiltration in UC Fh15-treated mice. These findings highlight the therapeutic potential of Fh15 for UC, as it modulates inflammatory responses, reduces leukocyte infiltration, and preserves colon integrity. Full article

Background and Objectives: Colonic anastomotic leaks are still a critical cause of morbidity and mortality. The study aimed to investigate the effects of esomeprazole on anastomotic healing after left colon anastomosis in rats with an ischemic colon. Material and Methods: Thirty-five male Wistar albino rats were divided into acute (CONTROL-A, ESP-A) and chronic (CONTROL-C, ESP-C) stage groups. Rats in the CONTROL-A and CONTROL-C groups underwent colonic anastomosis after hypoxia-reperfusion injury in the colon, and intraperitoneal saline was administered for three and ten days, respectively. Intraperitoneal 10 mg/day esomeprazole was given to the rats in the ESP-A and ESP-C groups for three and ten days after similar surgical procedures. Then, at scheduled times, 2 cm proximal and distal regions of the anastomosis line were resected, and bursting pressure was measured. Hydroxyproline (HYP), myeloperoxidase (MPO), malondialdehyde (MDA), caspase-3 (CSP3) and catalase (CAT), nitric oxide (NO), reduced glutathione (RGT), superoxide dismutase (SOD), TNF-α, IL-6, aspartate aminotransferase (AST), alanine aminotransferase (ALT) levels were measured in tissue and blood serum samples. Results: In the acute stage, CAT, NO, RGT, and SOD values in ESP-A group were lower than CONTROL-A group values. In addition, TNF, IL-6, ALT, and AST values in the ESP-A group were higher than the CONTROL-A group values between groups (p < 0.05). However, HYP and burst pressure values were not different between the groups. In the chronic stage, CAT, NO, RGT, SOD, CSP3, and burst pressure values in the ESP-A group were higher than CONTROL-A group values (p = 0.05). In contrast, TNF, IL-6, ALT, AST, HYP, MPO, and MDA values in the ESP-A group were lower than the CONTROL-A group values (p < 0.05). Conclusions: These results suggest that esomeprazole has anti-inflammatory and antioxidant activity in the chronic phase of ischemia–reperfusion injury, thus protecting the intestinal tissue from ischemic damage and enhancing the healing of the anastomosis line. Full article

Introduction: Many orally administered drugs are either unstable in the acidic environment of the stomach or cause moderate to severe side effects in the upper gastrointestinal tract (GIT). These limitations can reduce therapeutic efficacy, discourage patient compliance, worsen the disease, and even contribute to the risk of cancer development. To overcome these issues, drug release often needs to be modified and targeted to the distal parts of the GIT. This is typically achieved through the use of pH-sensitive polymer coatings or incorporation into polymeric delivery systems. With this in mind, the aim of this project was to design, develop, and characterize gellan gum-based beads for colon-specific prolonged release of mesalazine, with potential application in the chemoprevention and treatment of bowel diseases. Materials and Methods: The dehydrated capsules were characterized using Raman spectroscopy and scanning electron microscopy. The crosslinked gellan gum was additionally evaluated for cytotoxicity. Key parameters such as pH-dependent swelling behavior, drug content, encapsulation efficiency, and drug release in simulated gastrointestinal fluids were also assessed. Furthermore, the behavior of the capsules in the gastrointestinal tract was studied in a rat model to evaluate their in vivo performance. Results: Significant differences in drug release profiles were observed between formulations crosslinked solely with calcium ions and those additionally crosslinked with glutaraldehyde (GA). The incorporation of GA effectively prolonged the release of mesalazine. These findings were further supported by in vivo studies conducted on Wistar rats, where the GA-crosslinked formulation demonstrated a markedly extended release compared to the formulation prepared using only ionotropic gelation. Conclusions: The combination of ionotropic gelation and glutaraldehyde crosslinking in gellan gum-based beads appears to be a promising strategy for achieving colon-specific prolonged release of mesalazine, facilitating targeted delivery to the distal regions of the gastrointestinal tract. Full article

Backwash ileitis (BWI) refers to inflammation in the distal ileum in patients with extensive ulcerative colitis (UC) that is thought to be caused by a “reflux” or “backwash” of colonic contents. In the absence of well-defined diagnostic criteria for BWI, more recently, the term UC-associated ileitis was proposed in favor of the backwash theory, which questions the existence of backwash ileitis as a distinct disease-specific subset of patients. Moreover, distinguishing UC-associated BWI from terminal ileitis of Crohn’s disease or other conditions could be a diagnostic challenge and significantly affect treatment management. Therefore, clinical, endoscopic, histologic, and imagistic diagnostic features may aid in making this distinction. This literature review related to BWI outlines the hypothesis that the ileum may also become involved in UC as a primary manifestation of UC based on recent findings. This study also highlights the possibility that associated ileitis in UC patients may represent a potential risk factor for neoplasia, a positive association with primary sclerosing cholangitis, and a higher risk for the subsequent development of pouchitis after restorative proctocolectomy. It synthesizes recent key findings and highlights areas for further research. Full article

The aim of this study was to investigate the influence of solid dispersion (SD) formulation factors on improvement of the bioavailability and pharmacokinetic profile of clopidogrel after peroral administration using an in vitro–in silico approach. A clopidogrel-specific, physiologically based biopharmaceutical model (PBBM) was developed and validated to predict absorption and distribution of clopidogrel after peroral administration of the tested formulations. Clopidogrel solid dispersions were prepared using two polymers (poloxamer 407 and copovidone) and a drug-to-polymer ratio of 1:5 and 1:9. The results of the in vitro dissolution test under pH–media change conditions showed that the type and ratio of polymers notably influenced the release of clopidogrel from the SDs. It can be observed that an increase in the polymer content in the SDs leads to a decrease in the release of clopidogrel from the SDs. The predictive power of the constructed clopidogrel-specific PBBM was demonstrated by comparing the simulation results with pharmacokinetic data from the literature. The in vitro dissolution data were used as inputs for the PBBM to predict the pharmacokinetic profiles of clopidogrel after the peroral administration of SDs. SDs with copovidone (1:5) and poloxamer (1:9) showed the potential to achieve the highest drug absorption and bioavailability, with an improvement of over 100% compared to an immediate-release (IR) tablet. The sample with poloxamer (1:9) may have the potential to reduce inter-individual variability in clopidogrel pharmacokinetics due to absorption in the cecum and colon and associated lower first-pass metabolism in the liver. This suggests that distal intestine may be the targeted delivery site for clopidogrel, leading to improved absorption and bioavailability of the drug. This study has shown that an in vitro–in silico approach could be a useful tool for the development and optimization of clopidogrel formulations, helping in decision making regarding the composition of the formulation to achieve the desired pharmacokinetic profile. Full article

Colorectal cancer (CRC) is a leading cause of cancer-related morbidity and mortality, influenced by both genetic and epigenetic factors. Long non-coding RNAs (lncRNAs) such as GAS5 and CASC8 have been implicated in cancer susceptibility. This study aimed to assess the association of GAS5 rs145204276 ins/del and CASC8 rs10505477 A>G polymorphisms with CRC risk in a Romanian population. A case-control study was conducted, including 156 CRC patients and 195 healthy controls. Genotyping for GAS5 and CASC8 polymorphisms was performed using real-time PCR, and the association with CRC risk was evaluated using logistic regression to calculate odds ratios (OR) and 95% confidence intervals (CI). The carriers of GAS5 rs145204276 del allele was significantly associated with increased CRC risk (OR: 2.13, 95% CI: 1.24–3.63, p = 0.005) in a dominant model. In the subgroup analysis, the association of GAS5 rs145204276 ins/del polymorphism was restricted to distal colon cancer cases (OR: 2.98, 95% CI: 1.57–5.66, p = 0.001), advanced tumor stages (III + IV) (OR: 2.54, 95% CI: 1.31–4.91, p = 0.007), and poorly differentiated tumors (G3) (OR: 3.98, 95% CI: 1.49–10.59, p = 0.009). No significant correlation was found for the CASC8 rs10505477 A>G polymorphism. GAS5 rs145204276 polymorphism may influence CRC susceptibility, particularly in distal tumors and advanced stages. However, CASC8 rs10505477 polymorphism showed no association with CRC risk in this Romanian cohort. Full article

Afferent vagal neurons convey gut–brain signals related to the mechanical and chemical sensing of nutrients, with the latter also mediated by gut hormones secreted from enteroendocrine cells. Cell bodies of these neurons are located in the nodose ganglia (NG), with the right NG playing a key role in metabolic regulation. Notably, glucagon-like peptide-1 receptor (GLP1R) neurons primarily innervate the muscle layer of the stomach, distant from glucagon-like peptide-1 (GLP-1)-secreting gut cells. However, the co-expression of gut hormone receptors in these NG neurons remains unclear. Using RNAscope combined with immunohistochemistry, we confirmed GLP1R expression in a large population of NG neurons, with Glp1r, cholecystokinin A receptor (Cckar), and Neuropeptide Y Y2 Receptor (Npy2r) being more highly expressed in the right NG, while neurotensin receptor 1 (Ntsr), G protein-coupled receptor (Gpr65), and 5-hydroxytryptamine receptor 3A (5ht3a) showed equal expressions in the left and right NG. Co-expression analysis demonstrated the following: (i) most Glp1r, Cckar, and Npy2r neurons co-expressed all three receptors; (ii) nearly all Ntsr1- and Gpr65-positive neurons co-expressed both receptors; and (iii) 5ht3a was expressed in subpopulations of all peptide-hormone-receptor-positive neurons. Retrograde labeling demonstrated that the anterior part of the stomach was preferentially innervated by the left NG, while the right NG innervated the posterior part. The entire gastrointestinal (GI) tract, including the distal colon, was strongly innervated by NG neurons. Most importantly, dual retrograde labeling with two distinct tracers identified a population of neurons co-expressing Glp1r, Cckar, and Npy2r that innervated both the stomach and the colon. Thus, neurons co-expressing GLP-1, cholecystokinin (CCK), and peptide YY (PYY) receptors, predominantly found in the right NG, sample chemical, nutrient-induced signals along the entire GI tract and likely integrate these with mechanical signals from the stomach. Full article

The aim of this study was to investigate the microbiota composition and its potential interactions across seven gut locations (stomachs, jejuna, ilea, ceca, proximal colons, distal colons, and recta) in weaned pigs to identify key influencing microbiotas. To compare between microbiota compositions, 16S rRNA gene amplicon sequencing was performed. Six 70-day-old healthy crossbred (Duroc × Large White × Landrace) piglets were introduced as donors. A Bayesian network (BN) was used to examine the directional interactions among the microbiotas evaluated (seven mucosal and seven digesta microbiotas). Based on edge connectivity frequency, the microbiota in jejunal mucosa was the central hub node, influencing other microbiotas, especially the mucosal microbiotas of the ileum, cecum, distal colon, and rectum. The jejunal mucosa was dominated by Prevotella and lactobacilli, both recognized for their contributions to pig health. Among Prevotella, Prevotella copri and Prevotella sp. were predominant in jejunal mucosa (4.6% and 2.9%, respectively). Lactobacilli, including eight distinct species, were distributed throughout the gastrointestinal tract. Notably, Ligilactobacillus salivarius and Lactobacillus amylovorus, known as immune-enhancing bacteria, were abundant in jejunal mucosa (1.0% and 0.8%) and digestas (0.9% and 19.2%), respectively. The BN identified rectal mucosa and digestas as two terminal nodes, influenced by upstream microbiotas in the gastrointestinal tract. This finding supports the link between fecal microbiota and pig productivity, as the fecal microbiota, closely resembling the rectal microbiota, reflects the conditions of the microbiota throughout the gastrointestinal tract. Full article

Inflammatory bowel disease (IBD), encompassing Crohn’s disease and ulcerative colitis, involves chronic inflammation of the gastrointestinal tract. Current immune-modulating therapies are insufficient for 30–50% of patients or cause significant side effects, emphasizing the need for new treatments. Targeting the innate immune system and enhancing drug delivery to inflamed gut regions are promising strategies. Neutrophils play a central role in IBD by releasing reactive oxygen species (ROS) and neutrophil extracellular traps (NETs) —DNA-based structures with cytotoxic proteins—that contribute to mucosal damage and inflammation. Recent studies linking ROS production, DNA repair, and NET formation have identified NETs as potential therapeutic targets, with preclinical models showing positive outcomes from NET inhibition. Innovative oral drug delivery systems designed to target gut inflammation directly—without systemic absorption—could improve treatment precision and reduce side effects. Advanced formulations utilize properties such as particle size, surface modifications, and ROS-triggered release to selectively target the distal ileum and colon. A dual strategy that combines a deeper understanding of IBD pathophysiology to identify inflammation-related therapeutic targets with advanced drug delivery systems may offer significant promise. For instance, pairing NET inhibition with ROS-responsive nanocarriers could enhance treatment efficacy, though further research is needed. This synergistic approach has the potential to greatly improve outcomes for IBD patients. Full article