Search Results (558)

Biofilms are a spontaneously formed slimy matrix of extracellular polymeric substances (EPS) enveloping miniature bacterial colonies, which aid in pathogen colonization, shielding the bacteria from antibiotics, as well as imparting them resistance towards the same. Biofilms employ a robust communication mechanism called quorum sensing that serves to keep their population density constant. What is most significant about biofilms is that they contribute to the development of bacterial virulence by providing protection to pathogenic species, allowing them to colonize the host, and also inhibiting the activities of antimicrobials on them. They grow on animate surfaces (such as on teeth and intestinal mucosa, etc.) and inanimate objects (like catheters, contact lenses, pacemakers, endotracheal devices, intrauterine devices, and stents, etc.) alike. It has been reported that as much as 80% of human infections involve biofilms. Serious implications of biofilms include the necessity of greater concentrations of antibiotics to treat common human infections, even contributing to antimicrobial resistance (AMR), since bacteria embedded within biofilms are protected from the action of potential antibiotics. This review explores various contemporary strategies for controlling biofilms, focusing on their modes of action, mechanisms of drug resistance, and innovative approaches to find a solution in this regard. This review interestingly targets the extracellular polymeric matrix as a highly effective strategy to counteract the potential harm of biofilms since it plays a critical role in biofilm formation and significantly contributes to antimicrobial resistance. Full article

Ulcerative colitis is a chronic intestinal disorder that belongs to the category of inflammatory bowel diseases, and is usually characterized by the presence of bloody diarrhea and abdominal pain, due to an accelerated transit and intestinal sensibilization following inflammation of the colonic mucosa. However, the literature reports that ulcerative colitis may sometimes feature fecal stasis with constipation. This apparent paradox may be partially explained by the motor abnormalities of the large bowel following inflammation, damage to the enteric innervation, and the onset of parietal fibrosis over time. Moreover, some anorectal abnormalities such pelvic floor dyssynergia may explain the symptoms of constipation reported in subsets of patients. Since these abnormalities may be responsible for diagnostic delays and non- or partial responses to therapy, it is important to recognize them as early as possible to avoid incorrect clinical and therapeutic approaches to these patients. Full article

Crohn’s disease is a chronic inflammation affecting the gastrointestinal tract. To date, patients are commonly treated with corticosteroids or more aggressive biologics for high-risk subjects. Stem Cell Educator therapy has been successfully utilized to treat patients with type 1 diabetes and other autoimmune conditions. A 78-year-old patient with long-standing Crohn’s disease received one treatment with the Stem Cell Educator therapy, followed by clinical, radiographic, pathological examinations and immune marker testing by flow cytometry. After the treatment with Stem Cell Educator therapy, the patient’s clinical symptoms were quickly improved with normal bowel movements, without abdominal pain or rectal bleeding. Flow cytometry analysis revealed a marked decline in inflammatory markers, such as the percentage of monocyte/macrophage-associated cytokine interleukin-1 beta (IL-1β)⁺ cells, which reduced from 94.98% at the baseline to 18.21%, and down-regulation of the percentage of chemokine CXCL16⁺ cells from 91.92% at baseline to 42.58% at 2-month follow-up. Pathologic examination of the biopsy specimens from colonoscopy five weeks and six months post-treatment showed ileal mucosa with no specific abnormality and no significant inflammation or villous atrophy; no granulomas were identified. A follow-up CT scan four and one-half months post-treatment showed no evidence of the previously seen stenosis of the ilio-colonic anastomosis with proximal dilatation. Stem Cell Educator therapy markedly reduced inflammation in the subject with Crohn’s disease, leading to durable clinical, immunological, radiographic, and pathological improvements. Full article

Enteroendocrine cells (EECs) are specialized secretory cells in the gut epithelium that differentiate from intestinal stem cells (ISCs). Mature EECs secrete incretin hormones that stimulate pancreatic insulin secretion and regulate appetite. Decreased EEC numbers and impaired secretion of the incretin glucagon-like peptide-1 (GLP1) have been implicated in obesity-associated metabolic complications. Gut microbial metabolites of dietary tryptophan (TRP) were recently shown to modulate ISC proliferation and differentiation. However, their specific effects on EEC differentiation are not known. We hypothesized that the gut microbial metabolites of dietary tryptophan counteract impaired GLP1 production and function in obesity by stimulating EEC differentiation from ISCs. We utilized complementary models of human and rat intestines to determine the effects of obesity or TRP metabolites on EEC differentiation. EEC differentiation was assessed by the EEC marker chromogranin A (CHGA) levels in the intestinal mucosa of normal versus obese rats. The effects of TRP metabolites on EEC differentiation were determined in human intestinal organoids treated with indole, a primary TRP metabolite, or the culture supernatant of Lactobacillus acidophilus grown in TRP media (LA-CS-TRP). Our results showed that the mRNA and protein levels of CHGA, the EEC marker, were significantly decreased (~60%) in the intestinal mucosa of high-fat-diet-induced obese rat intestines. The expression of the transcription factors that direct the ISC differentiation towards the EEC lineage was also decreased in obesity. In human organoids, treatment with indole or LA-CS-TRP significantly increased (more than 2-fold) CHGA levels, which were blocked by the aryl hydrocarbon receptor (AhR) antagonist CH-223191. Thus, the stimulation of EEC differentiation by colonic microbial metabolites highlights a novel therapeutic role of TRP metabolites in obesity and associated metabolic disorders. Full article

Diverticulosis is characterized by sac-like bulges of the mucosa through weakened portions of the intestinal wall, and is a common pathology observed in adult patient populations. The majority of diverticular disease and associated complications, such as inflammation of diverticula, form within the colon, with less frequent cases of diverticular disease observed in the small bowel. We present the case of a 48-year-old female who presented to the emergency department with a two-day history of abdominal pain, fever, and nausea. Upon admission, vital signs indicated fever and laboratory analysis demonstrated elevated white blood cell count. The patient’s workup included a computed tomography (CT) scan of the abdomen which revealed diffuse small bowel diverticulitis with surrounding inflammation, lymph node enlargement, and bowel wall thickening. CT scan of the abdomen with evidence of diverticula in the bowel wall is diagnostic of diverticulosis. Treatment could include bowel rest, clear liquid diet, broad-spectrum antibiotics, or surgical intervention. This case emphasizes the importance of CT imaging and consideration of broad differential diagnosis in patients presenting with abdominal pain due to the rare presentation of small bowel diverticulitis and aims to contribute to the current understanding and treatment of clinically significant diverticular pathologies. Full article

The aim of this study was to determine whether a low dose of zearalenone (ZEN) affects the mRNA expression of the CYP1A1 (P450 cytochrome) and GSTπ1 (glutathione S-transferase) genes in the large intestine of pre-pubertal gilts. Materials: Control (C) group gilts (n = 18) received a placebo. Experimental (E) group gilts (n = 18) were orally administered 40 μg ZEN/kg body weight (BW) each day before morning feeding for 42 days. Three animals from each group were sacrificed each week of the study. Tissue samples were collected from the medial parts of the ascending colon and the descending colon on six dates. Results: Zearalenone concentrations were multiple times higher in the last three weeks of exposure, and ZEN metabolites were not detected. In phase I, CYP1A1 mRNA expression in the ascending colon was suppressed in the final three weeks of exposure, which substantially increased the ZEN concentration in the descending colon. In phase II, ZEN levels were high in the descending colon due to CYP1A1 suppression in the ascending colon. Consequently, the phase II detoxification processes could not take place due to the absence of a substrate. Conclusion: This study demonstrated that low-dose ZEN mycotoxicosis disrupts the expression of the CYP1A1 and GSTπ1 genes, which co-participate in the enzymatic biotransformation of ZEN in both examined sections of the large intestine. The above could have contributed to increased ZEN accumulation in the mucosa of the descending colon in the last three weeks of exposure. Full article

This study evaluated the inhibitory activity of quercetin at sub-inhibitory concentrations on quorum-sensing (QS) molecules in vitro and the effects of dietary supplementation with quercetin (for 24 consecutive days) on enterotoxigenic Escherichia coli (ETEC)-induced inflammatory and oxidative stress responses in weaned piglets. The piglets were fed one of three diets: the basal diet (Con), ETEC challenge (K88) after the basal diet, or ETEC challenge (quercetin + K88) after the basal diet supplemented with 0.2% quercetin. In vitro experiments revealed that 5 mg/mL quercetin exhibited the strongest QS inhibitory activity and reduced pigment production by Chromobacterium violaceum ATCC12472 by 67.70%. In vivo experiments revealed that quercetin + K88 significantly increased immunoglobulin A (IgA), immunoglobulin M (IgM), and immunoglobulin G (IgG) levels in the serum, ileum mucosa, and colon mucosa; increased glutathione peroxidase (GSH-Px), catalase (CAT), and superoxide dismutase (SOD) levels in the serum, liver, and colon mucosa; and decreased cluster of differentiation 3 (CD3) and cluster of differentiation 8 (CD8)activity in the serum compared with K88 alone. Quercetin + K88 significantly alleviated pathological damage to the liver and spleen and upregulated antioxidant genes (nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1(HO-1), CAT, SOD, and glutathione s-transferase (GST)). Inducible nitric oxide synthase (iNOS) and kelch-like ech-associated protein 1 (Keap1), which cause oxidative damage to the liver and spleen, were significantly downregulated. The acetic acid content in the cecum was significantly increased, and the E. coli count and QS signal molecule autoinducer-2 (AI-2) yield were significantly reduced. In conclusion, 0.2% dietary quercetin can alleviate ETEC-induced inflammation and oxidative stress in weaned piglets. Full article

Helicobacter pylori, which colonizes the human gastric mucosa, uses a cluster of polar, sheathed flagella to swim across the mucous layer of the stomach. The function and biogenesis of the H. pylori flagellar sheath are poorly understood. Cardiolipin is a phospholipid that accumulates in regions of the membrane that have negative curvature, such as the cell pole, cell septum, and flagellar sheath. The final step in cardiolipin biosynthesis is catalyzed by cardiolipin synthase. H. pylori has at least two cardiolipin synthases, one of which is cardiolipin synthase C (ClsC). Bioinformatic analysis revealed that homologs of H. pylori ClsC are restricted to Helicobacter species that have sheathed flagella and the ClsC homologs are predicted lipoproteins. Fluorescence microscopy revealed that a ClsC super-folder green fluorescent protein localized to the cell pole and cell septum in H. pylori G27. Comparing the proteomes of isolated sheathed flagella from the H. pylori B128 wild type and a clsC::cat mutant, we identified five proteins that were absent in the mutant flagellum preparations. One of the proteins was FaaA, an autotransporter that localizes to the flagellar sheath. These findings suggest that the localization of FaaA and possibly other proteins to the flagellar sheath is dependent on ClsC. Full article

Three-dimensional (3D) scaffold systems have proven instrumental in advancing our understanding of polymicrobial biofilm dynamics and probiotic interactions within the oral environment. Among oral probiotics, Streptococcus salivarius K12 (Ssk12) has shown considerable promise in modulating microbial homeostasis; however, its long-term therapeutic benefits are contingent upon successful and sustained colonization of the oral mucosa. Despite its clinical relevance, the molecular mechanisms underlying the adhesion, persistence, and integration of Ssk12 into the native oral microbiome/biofilm remain inadequately characterized. In this pilot study, we explored the temporal colonization dynamics of Ssk12 and its impact on the structure and functional profiles of salivary-derived biofilms cultivated on melt-electrowritten poly(ε-caprolactone) (MEW-mPCL) scaffolds, which emulate the native oral niche. Colonization was monitored via fluorescence in situ hybridization (smFISH), confocal microscopy, and RT-qPCR, while shifts in community composition and function were assessed using 16S rRNA sequencing and meta-transcriptomics. A single administration of Ssk12 exhibited transient colonization lasting up to 7 days, with detectable presence diminishing by day 10. This was accompanied by short-term increases in Lactobacillus and Bifidobacterium populations. Functional analyses revealed increased transcriptional signatures linked to oxidative stress resistance and metabolic adaptation. These findings suggest that even short-term probiotic colonization induces significant functional changes, underscoring the need for strategies to enhance probiotic persistence. Full article

Recent pan-cancer transcriptome analysis has revealed differential activity of two alternative PHF19 gene promoters in malignant versus non-malignant gut mucosa. One of these promoters upregulated in colon cancer leads to the expression of the PHF19-207 transcript, suggesting its potential role in tumor promotion. The objective of this study was to investigate the function of PHF19-207 using in silico tools and publicly available data, as well as to assess its expression in colon cancer. Expression analyses were conducted via qPCR and RNA sequencing on RNA extracted from the immortalized colonic epithelial cell line HCEC-1CT, as well as a series of colon cancer cell lines cultured in both 2D and 3D environments. The expression of PHF19-207 was found to be elevated in all malignant cell lines compared to the non-malignant HCEC-1CT cell line in both culture conditions, with the most prominent increase observed in cell lines derived from advanced stages of the disease and in the HCEC-1CT cell line overexpressing KRAS. Furthermore, the PHF19-207 transcript was detected in exosomes derived from malignant cells. These findings suggest that PHF19-207 holds potential as a diagnostic biomarker. In addition, in silico analyses indicate that this transcript may function as a long non-coding RNA involved in the regulation of gene expression. Further functional investigations are required to elucidate its precise role in colon carcinogenesis. Full article

Repairing and regenerating tissue barriers is a key challenge in regenerative medicine. Stem cells play a crucial role in restoring the structural and functional integrity of key epithelial barrier surfaces, including the skin and mucosa. This review analyzes the role of dental pulp stem cells (DPSCs) and their derivatives, including extracellular vesicles, conditioned medium, and intracellular factors, in accelerating skin wound healing. The key mechanisms include: (1) DPSCs regulating inflammatory microenvironments by promoting anti-inflammatory M2 macrophage polarization; (2) DPSCs activating vascular endothelial growth factor (VEGF) to drive angiogenesis; (3) DPSCs optimizing extracellular matrix (ECM) spatial structure through matrix metalloproteinase/tissue inhibitor of metalloproteinase (MMP/TIMP) balance; and (4) DPSCs enhancing transforming growth factor-β (TGF-β) secretion to accelerate granulation tissue formation. Collectively, these processes promote wound healing. In addition, we explored potential factors that accelerate wound healing in DPSCs, such as oxidative stress, mechanical stimulation, hypertension, electrical stimulation, and organoid modeling. In addition to demonstrating the great potential of DPSCs for skin repair, this review explores their translational prospects in mucosal regenerative medicine. It covers the oral cavity, esophagus, colon, and fallopian tube. Some studies have found that combining DPSCs and their derivatives with drugs can significantly enhance their biological effects. By integrating insights from skin and mucosal models, this review offers novel ideas and strategies for treating chronic wounds, inflammatory bowel disease, and mucosal injuries. It also lays the foundation for connecting basic research results with clinical practice. This represents a significant step forward in tackling these complex medical challenges and lays a solid scientific foundation for developing more targeted and efficient regenerative therapies. Full article

Background/Objectives: Keratins form a crucial component of the epithelial cytoskeleton, playing an essential role in maintaining tissue architecture and coordinating key cellular functions. KRT80 is a type II keratin that has emerged as an oncogenic driver in several malignancies, yet its involvement in colorectal cancer (CRC) remains unclear. Here, we investigated the molecular interaction between miR-195-5p, KRT80 expression, and CRC growth. Methods: Potential miR-195-5p binding sites in the KRT80 3′-UTR were identified through the use of integrated bioinformatic analyses, while publicly available datasets confirmed a significant overexpression of KRT80 in CRC tissues compared to normal mucosa. This finding was further validated through the use of mRNA and protein analysis in paired tumor and adjacent normal samples from CRC patients. Results: Functional assays involving CRC cell lines showed that transfection with miR-195-5p mimics led to a significant downregulation of KRT80 expression, reflecting the effects of direct KRT80 silencing by siRNA. Both molecular approaches induced G₁-phase cell cycle arrest, concomitantly with reductions in G₂/M populations. Furthermore, the in vivo delivery of miR-195-5p mimics in a mouse model of colitis-associated CRC resulted in a significant reduction in Krt80 expression in the colon. Conclusions: Collectively, our results reveal that miR-195-5p negatively regulates KRT80 expression, contributing to its tumor-suppressive activity in colorectal cancer and highlighting a molecular mechanism with potential therapeutic relevance. Full article

Constipation, a widespread gastrointestinal disorder, imposes significant burdens on healthcare systems the and global health-related quality of life, yet current options remain suboptimal due to limited mechanistic understanding and efficacy limitations. Given the pivotal significance of the interactions between the gut microbiota and the host on governing bowel movement, we employed a multi-modal approach integrating animal experiments, ELISA, histopathology, qRT-PCR, GC-MS, and 16S rRNA metagenomics to evaluate the functional potential of Lactobacillus rhamnosus LRa05 against loperamide-induced constipation in mice. LRa05 treatment markedly alleviated constipation symptoms, as evidenced by reduced first black stool expulsion time, increased fecal moisture, and enhanced intestinal motility. Mechanistic investigations revealed that LRa05 balanced gastrointestinal regulatory peptides. It also downregulated aquaporin (AQP4/AQP8) mRNA levels and activated the SCF/C-Kit signaling pathway. These effects contributed to the restoration of intestinal peristalsis. Furthermore, LRa05 rebalanced gut microbiota composition by enriching beneficial, including Alloprevotella and Lachnospiraceae NK4A136, key SCFA producers. Thus, LRa05 could boost short chain fatty acid (SCFA) production, which is vital for stimulating intestinal motility, improving mucosal function, and relieving constipation. These findings demonstrated that LRa05 could mitigate constipation through a multi-target mechanism: regulating motility-related gene transcription, restructuring the microbial community, balancing gastrointestinal peptides, repairing the colonic mucosa, and promoting SCFAs for fecal hydration. Our study positions LRa05 as a promising probiotic candidate for constipation management. Full article

Background and Objectives: Infant feeding practices play a crucial role in shaping the oral microbiome, modulating inflammatory responses, and maintaining epithelial health during the first year of life. Breastfeeding promotes the growth of beneficial bacteria and supports a diverse, stable microbial community. In contrast, formula feeding is associated with increased colonization by potentially pathogenic bacteria, such as Staphylococcus and Escherichia coli, which may elevate the risk of infections, oral diseases, and inflammation. This study investigates the effects of breastfeeding versus formula feeding on oral bacterial growth, epithelial cell integrity, and interleukin-17 (IL-17) expression in infants aged 1–12 months. Materials and Methods: A total of 60 infants (30 breastfed and 30 formula-fed) were recruited from pediatric clinics in the Qassim region. Microbial cultures quantified bacterial colony-forming units (CFUs), and epithelial cell morphology was assessed through the microscopic analysis of mucosal scrapings. IL-17 concentrations were quantified from the oral mucosa through enzyme-linked immunosorbent assay. Statistical analyses, including t-tests and chi-square tests, compared bacterial loads, IL-17 levels, and indicators of epithelial health between groups. Adjustment for potential confounders was achieved through multivariate statistical analysis. Results: Formula-fed infants showed significantly higher IL-17 levels than breastfed infants (p < 0.001), indicating a stronger pro-inflammatory profile. Breastfed infants exhibited lower inflammation, improved epithelial health, and reduced cellular debris compared to formula-fed infants, who had higher bacterial loads. A significant correlation was found between epithelial health and bacterial clustering, with clearer epithelial cells associated with lower bacterial colonization. Conclusions: Formula feeding was associated with increased salivary IL-17 levels, greater bacterial colonization, and compromised epithelial integrity, indicating a heightened pro-inflammatory state and potential vulnerability to mucosal irritation or infection. Breastfeeding appeared to confer protective effects by promoting healthier microbial balance, epithelial integrity, and reducing inflammatory responses. These findings underscore the immunological and microbial benefits of breastfeeding in supporting oral health during infancy. Full article

Ulcerative colitis (UC) is a chronic inflammatory bowel disease (IBD) associated with recurrent inflammation and ulceration of the colonic mucosa. Conventional treatments, including corticosteroids, have significant side effects, driving the need for safer, effective alternatives. The present study aimed to investigate the mitigating effects of Epilobium angustifolium extract (EAE) in a Dextran sulfate sodium (DSS)-induced colitis mouse model, in a comparative manner to the reference drug dexamethasone (DXM). The severity and progression of colitis were evaluated through disease activity indices and a range of inflammatory and oxidative stress markers, assessed using multiple analytical methods. EAE treatment significantly reduced colonic inflammation, as indicated by decreased myeloperoxidase (MPO) activity, lower levels of malondialdehyde (MDA), and reduced white blood cell counts. EAE also enhanced antioxidant defenses, increasing glutathione (GSH) levels by 64%, and boosting catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) activities by 36%, 53%, and 70%, respectively. Histopathological analysis confirmed EAE’s efficacy in attenuating colonic injury and inflammation. The blood parameters hemoglobin, erythrocytes, and hematocrit were also improved. Our study shows that EAE has potential as a natural therapeutic candidate for the treatment of UC, demonstrating efficacy comparable to that of conventional pharmacological treatments. Full article