Search Results (849)

A diverse bacterial community colonizes the respiratory system, including commensals such as Staphylococcus epidermidis (S. epidermidis) and Streptococcus salivarius (S. salivarius), as well as facultative pathogens like Staphylococcus aureus (S. aureus). This study aimed to establish a colonized cell culture model to investigate the impact of these bacteria on influenza A virus (IAV) infection. Respiratory epithelial cells were exposed to S. epidermidis, S. salivarius, or S. aureus, using either live or heat-inactivated bacteria, followed by IAV infection. Cell integrity was assessed microscopically, cytotoxicity was measured via LDH assay, and inflammatory responses were analyzed through cytokine expression. Additionally, macrophage function was examined in response to bacterial colonization and IAV infection. While commensals maintained epithelial integrity for 48 h, S. aureus induced severe cell damage and death. The most pronounced epithelial destruction was caused by coinfection with S. aureus and IAV. Notably, commensals did not confer protection against IAV but instead enhanced epithelial inflammation. These effects were dependent on live bacteria, as inactivated bacteria had no impact. However, prior exposure to S. epidermidis and S. salivarius improved macrophage-mediated immune responses against IAV. These findings suggest that while individual commensals do not directly protect epithelial cells, they may contribute to immune training and enhance lung defense mechanisms. Full article

Colibactin toxin-producing Escherichia coli (pks+ E. coli) strains are associated with the occurrence of colorectal cancer in humans. These strains induce DNA damage when in close contact with the cells of the intestinal epithelium. Therefore, maintaining the integrity of the mucus layer that covers the intestinal epithelial mucosa is crucial for counteracting the effects of colibactin. The Vat protein is a mucin protease capable of degrading MUC2 mucus proteins that was previously described in adherent and invasive Escherichia coli strains. Our work shows that the vat gene is found in the genome of all pks+ E. coli strains isolated from patients with colon cancer. In mucus-producing HT29-16E cells, we demonstrated that the Vat protein of E. coli pks+ allows bacteria to penetrate mucus and to reach the epithelial cells. Cells infected with the E. coli pks + vat- strain show a reduction in γ-H2AX staining, a marker of DNA damage. Infection of Apc^Min/+ mice with the E. coli pks + vat+ strain or the E. coli pks + vat- mutant revealed that Vat enhances the ability of pks+ E. coli strains to colonize the intestinal mucosa and, in turn, their pro-carcinogenic effects. This study reveals that Vat promotes crossing of the intestinal mucus layer, gut colonization, and the carcinogenicity of pks+ E. coli. Full article

Mucin, a heavily glycosylated glycoprotein, serves an important function in forming protective and immune defense barriers against the exterior environment on epithelial surfaces. While secreted-type mucins are involved in mucous production, transmembrane mucins, which contain O-glycosylated tandem repeats, play a pivotal role in cellular signaling, especially in immune modulation and mediating inflammatory response. However, dysregulation in mucin expressions, such as MUC1, MUC2, MUC4, MUC5AC, and MUC16, have been observed in many cancer cells. More specifically, alterations in the expression and glycosylation of MUC1 have been associated with the upregulation of pathways involving the cell proliferation, angiogenesis, migration, and invasion of cancer cells. With mucin’s extensive involvement in cancer biology, several mucin biomarkers, such as CA125, CA19-9, and CEA, have been utilized as diagnostic and prognostic monitoring biomarkers in ovarian, pancreatic, and colon cancer. Vaccines and antibody therapy against abnormal mucin glycosylation have also been investigated for potential therapy for mucin-related cancers that are resistant to traditional chemotherapy agents. Despite the lack of specificity in mucin biomarkers and challenges in efficient drug delivery systems, the current advancement in mucin-targeted immunotherapy highlighted the pivotal potential in developing therapeutic targets to improve cancer prognosis. Full article

Helicobacter pylori (H. pylori) is a Gram-negative bacterium that colonizes the human stomach and is associated with several gastric diseases, including gastritis, peptic ulcer disease, and gastric cancer. The bacterium’s ability to thrive in the harsh gastric environment is due, to some extent, to its stress response mechanisms, with its heat shock proteins (HSPs) playing a putative, yet not fully understood, role in these adaptive processes. HSPs are a family of molecules, highly conserved throughout phylogenesis, that assist in protein folding, prevent aggregation, and ensure cellular homeostasis under stressful conditions. In H. pylori, HSPs contribute to survival in the stomach’s acidic environment and oxidative stress. Furthermore, they aid in the bacterium’s ability to adhere to gastric epithelial cells, modulate the host immune response, and form biofilms, all contributing to chronic infection and pathogenicity. The role of microbial HSPs in antibiotic resistance has also emerged as a critical area of research, as these proteins help stabilize efflux pumps, protect essential proteins targeted by antibiotics, and promote biofilm formation, thereby reducing the efficacy of antimicrobial treatments. Among bacterial HSPs, GroEL and DnaK are probably the major proteins that control most of the H. pylori’s functioning. Indeed, both proteins possess remarkable acid resistance, high substrate affinity, and dual roles in protein homeostasis and host interaction. These features make them critical for H. pylori’s adaptation, persistence, and pathogenicity in the gastric niche. In addition, recent findings have also highlighted the involvement of HSPs in the crosstalk between H. pylori and gastric epithelial cells mediated by the release of bacterial outer membrane vesicles and host-derived exosomes, both of these extracellular vesicles being part of the muco-microbiotic layer of the stomach and influencing cellular signalling and immune modulation. Considering their critical role in the survival and persistence of bacteria, microbial HSPs also represent potential therapeutic targets. Strategies aimed at inhibiting microbial HSP function, combined with conventional antibiotics or developing vaccines targeting microbial HSPs, could provide new avenues for the treatment of H. pylori infections and combat antibiotic resistance. This review explores the multifaceted roles of microbial HSPs in the pathogenesis of H. pylori, highlighting their contributions to bacterial adhesion, immune evasion, stress response, and antibiotic resistance. Full article

Background/Objectives: Indigo naturalis (IN) is a traditional Chinese medicine concocted from medicinal plants such as Baphicacanthus cusia (Nees) Bremek. IN has multifaceted pharmacological activities. Recent research highlights the remarkable efficacy of IN in treating ulcerative colitis (UC). This study investigates the efficacy of Indigo Naturalis prepared using a novel method (NIN) in ameliorating UC. Methods: We have developed a new IN processing technology without the use of lime. Correspondingly, the content of active ingredients has relatively increased in NIN. In this study, dextran sulfate sodium salt (DSS) induced UC models among male KM mice, and the protective effects of NIN on UC were verified. Results: NIN could significantly improve weight loss, diarrhea and prolapse, bloody stools, elevated Disease Activity Index (DAI) and alleviate the colitis symptoms of mice; it could also improve the shortening of colon, disappearance of intestinal crypts, epithelial cell destruction and inflammatory infiltration caused by UC; and it could also significantly reduce the Histological Index (HI). In addition, NIN relieved the inflammatory response by decreasing the content of pro-inflammatory cytokines TNF-α and IL-1β and elevating the content of anti-inflammatory cytokines IL-10 and IL-22. It also restored the intestinal mucosal barrier by increasing the level of MUC2 protein expression at the site of colonic injury. Conclusions: The significant effects of NIN on UC were verified for the first time, suggesting that NIN was worth further developing into a novel therapeutic drug and, necessarily, further safety evaluations and comparisons with traditional IN will help in the application of NIN. Full article

Tumor-associated macrophages (TAMs) play a pivotal role in cancer regulation by influencing tumor growth, metastasis, and the immune microenvironment. By providing low doses and ultra-low doses (ULD) of immune regulators to the organism, micro-immunotherapy (MI) medicines (MIM) could be seen as valuable adjuvant drugs in the context of a wide range of pathological conditions, including cancers. Thus, these MIM could target TAMs, affecting their phenotype and activities. In this study, the anti-tumor and the immune-stimulatory effects of four capsules out of the ten composing the Labo’life’s MIM 2LC1^® (2LC1-1, 2LC1-6, 2LC1-7, and 2LC1-8), as well as the specific nucleic acid (SNA^®) sequence SNA-MYC present at ULD in this medicine have been evaluated in vitro, in several cancer models, and in human monocyte-derived macrophages. Our results showed that the tested MI formulations increased the tumor cell death of spheroids from HCT-116 colon cancer cells, while reducing the spheroid volume. Moreover, the treatments impaired the clonogenic capabilities of two cancer cell lines from epithelial origin, the LNCaP prostate cancer and the MCF-7 breast cancer cells. Interestingly, ULD of the SNA-MYC shared similar anti-cancer capabilities in those models, and it led to a significant reduction in the expression of C-MYC when evaluated in a model of human M2 macrophages. In the same model, the MI formulations also increased the expression of CD86 and HLA-DR, two markers of M1 anti-tumor macrophages. In addition, the tested items modulated the secretion of a panel of chemokines related to macrophage activity and immune cell recruitment. Finally, our results showed that 2LC1-8 increased the phagocytosis capabilities of human monocyte-derived macrophages, thus possibly contributing to sustaining the immune functions of M1, which are crucial in the context of cancer. Even if more research is needed to uncover their exact mechanism of action, these results suggest that the tested capsules of 2LC1 as well as ULD of SNA-MYC display both anti-tumor and immune-enhancing effects. Full article

Inflammatory bowel disease (IBD), encompassing Crohn’s disease and ulcerative colitis, is characterized by chronic intestinal inflammation and epithelial barrier disruption. Emerging evidence highlights mitochondrial dysfunction as a pivotal contributor to IBD pathogenesis, where impaired mitochondrial homeostasis in intestinal epithelial cells (IECs) disrupts redox balance, exacerbates oxidative stress, and triggers apoptosis, further compromising barrier integrity. This study investigated the therapeutic effects of Engeletin (Eng), a dihydroflavonoid from Smilax glabra Roxb., in dextran sulfate sodium (DSS)-induced colitis mice and colonic organoid models. Eng administration (10, 20, 40 mg/kg) significantly alleviated colitis symptoms, including weight loss, disease activity index (DAI) scores, and colon shortening, while restoring intestinal barrier integrity through the upregulation of tight junction proteins (ZO-1, claudin-1) and goblet cell preservation. Eng suppressed NF-κB-mediated inflammation and activated the Nrf2 antioxidant pathway, as well as reduced oxidative stress markers (MDA, CAT, GSH, and SOD). It attenuated epithelial apoptosis by balancing pro- and anti-apoptotic proteins (Bax/Bcl2, c-caspase3) and ameliorated mitochondrial dysfunction via enhanced ATP production, mtDNA levels, and complex I/IV activity. Mechanistically, Eng activated the AMPK/SIRT1/PGC-1α axis, and pharmacological inhibition of PGC-1α abolished its mitochondrial protective and anti-apoptotic effects. These findings demonstrate that Eng alleviates colitis by targeting mitochondrial homeostasis and oxidative stress through AMPK/SIRT1/PGC-1α signaling, offering a multitargeted strategy for IBD therapy. Full article

Meripilus giganteus (Pers.) P. Karst. is a basidiomycete fungus known for its bioactive properties, including antioxidant, antimicrobial, and cytotoxic effects. Although research has largely focused on fruiting bodies, mycelium obtained through in vitro culture offers a sustainable and potentially scalable source of bioactive metabolites. This study aimed to compare the chemical composition and biological activity of extracts from the fruiting bodies and mycelium of M. giganteus. Key compound groups were analyzed using high-performance liquid chromatography (HPLC), and biological activity was assessed through DPPH and ABTS antioxidant assays and MTT-based cytotoxicity testing on human gastrointestinal cancer and normal colon epithelial cell lines. The results revealed distinct metabolite profiles between fungal forms and demonstrated that solvent type strongly influenced extraction efficiency. Cytotoxicity assays indicated moderate activity of both extract types, with some selectivity towards colorectal cancer cell lines. These findings suggest that M. giganteus mycelium may serve as a promising alternative to fruiting bodies for the production of antioxidant and potentially chemopreventive compounds. Further studies are recommended to optimize cultivation and extraction conditions to enhance both metabolite yield and biological activity. Full article

Background/Objectives: Colon adenocarcinoma (COAD), the most prevalent form of colorectal cancer, remains a leading cause of cancer-related mortality. Advances in various treatments for COAD have significantly improved treatment outcomes. However, therapeutic limitations persist, highlighting the need for personalized strategies driven by novel biomarkers. The aim was to identify key hub genes that could be potential biomarkers of COAD using comprehensive bioinformatic analyses. Methods: Differentially expressed genes (DEGs) and co-DEGs were identified from COAD gene expression datasets. Functional enrichment analyses, including Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, were performed. Hub genes were extracted from protein–protein interaction (PPI) networks and validated epigenetically using microRNA (miRNA) and DNA methylation datasets. Their expression patterns were further examined via single-cell RNA sequencing (scRNA-seq) and immune cell infiltration analysis. Prognostic relevance was assessed based on tumor metastasis and survival outcomes. Results: Gene expression profiling identified 118 co-DEGs, with GO and KEGG pathway analyses revealing significant pathway enrichment. PPI network analysis pinpointed 27 key co-DEGs. Epigenetic profiling indicated that both miRNA interference and DNA methylation regulate CLDN1, INHBA, and CXCL12 expression levels. scRNA-seq analysis showed elevated CLDN1 expression in epithelial cells and INHBA in myeloid cells, and reduced CXCL12 expression in stromal cells. Prognostic analysis further demonstrated that CLDN1 and INHBA are significantly associated with poor COAD outcomes. Conclusions: We identified some potential prognostic biomarkers for patients with COAD. Further experimental validation is required to translate these findings into precision medicine for COAD. Full article

Respiratory viral infections trigger immune and inflammatory responses that can be associated with excessive oxidative stress, glutathione (GSH) depletion, and a cytokine storm that drives virus-induced cell/tissue damage and severe disease. Erdosteine is a thiol-based drug with proven mucolytic, anti-inflammatory, antioxidant, and antibacterial properties, but less is known about its antiviral effects. We performed in vitro studies to investigate the antiviral and anti-inflammatory activity of erdosteine in A549-hACE2 human lung epithelial cells infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or respiratory syncytial virus (RSV) and in Caco-2 human colon carcinoma cells infected with influenza A virus (H1N1). The cells were treated with different concentrations of erdosteine or its active metabolite 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MET-1) before and after viral infection. The viral replication/load in the cell culture supernatants was measured by real-time quantitative polymerase chain reaction (RT-qPCR) assay and digital droplet PCR. The gene expression of innate immune response signaling pathways and oxidative stress was analyzed by reverse transcription PCR custom-array. The results showed that erdosteine and its active metabolite, at concentrations consistent with an approved therapeutic human dosage, were not directly cytotoxic and had significant antiviral effects in cells pre-infected with SARS-CoV-2, RSV, and H1N1. The transcriptome analysis showed that erdosteine activated innate immune responses by stimulating overexpression of type I interferon and inflammasome pathways and modulated oxidative stress by inducing the modulation of oxidative stress and GSH pathways. These findings suggest that erdosteine may be a useful treatment for respiratory viral infections. Full article

Gastric intestinal metaplasia (GIM) is a precancerous lesion and the key risk factor in the development of gastric cancer (GC), but early detection and treatment remain challenging. The traditional endoscopic diagnosis of metaplastic lesions is complicated by an increased rate of inappropriateness and false negativity. Although early interventions with H. pylori eradication, as well as endoscopic therapy results, were promising, there is still a significant unmet need to control GIM progression and recurrences. Molecular alterations, such as an increased DNA methylation index, have been identified as a crucial factor in the downregulation of tumor suppressor genes, such as the caudal-type homeobox (CDX2) gene, which regulates epithelial cell proliferation and GIM progression and is associated with treatment failure. CDX2 is downregulated by promoter hypermethylation in the colonic-type epithelium, in which the methylation was correlated with reduced intake of dietary folate sources. Tumor cells alter to dietary methionine sources in the biosynthesis of S-Adenosylmethionine, a universal methyl donor for transmethylation, under the conditions of limited folate and B12 availability. The gut microbiota also exhibited a shift in microbial composition, which could influence the host’s dietary methionine metabolism. Meanwhile, activated oncogenic signaling via the PI3K/Akt/mTORC1/c-MYC pathway could promotes rewiring dietary methionine and cellular proliferation. Tumor methionine dependence is a metabolic phenotype that could be helpful in predictive screening of tumorigenesis and as a target for preventive therapy to enhance precision oncology. This review aimed to discuss the molecular alterations in GIM to shed light on the alteration of methionine metabolism, with insight into new diagnostic and treatment approaches and future research directions. Full article

The atypical activation of the epithelial-to-mesenchymal transition represents one of the main mechanisms driving cancer cell dissemination. It enables epithelial cancer cells to detach from the primary tumor mass and gain survival advantages in the bloodstream, significantly contributing to the spread of circulating tumor cells. Notably, epithelial-to-mesenchymal transition is not a binary process but rather leads to the formation of a wide range of cell subpopulations characterized by the simultaneous expression of both epithelial and mesenchymal markers. Therefore, analyzing the modulation of EMT hallmarks during the conversion from healthy cells to metastatic cancer cells, which acquire stem mesenchymal characteristics, is of particular interest. This study investigates the expression of a panel of epithelial-to-mesenchymal transition-related genes in healthy cells, primary and metastatic cancer cells, and in mesenchymal cell lines, derived from various tissues, including the lung, colon, pancreas, skin, and neuro-ectoderm, with the aim of identifying potential cut-off values for assessing cancer aggressiveness. Interestingly, we found that the expression levels of CDH1, which encodes the epithelial marker E-cadherin, CDH5, encoding vascular endothelial cadherin, and the epithelial-to-mesenchymal transition-transcription factor ZEB1, effectively distinguished primary from metastatic cancer cells. Additionally, our data suggest a tissue-specific signature in the modulation of epithelial-to-mesenchymal transition markers during cancer progression. Overall, our results underscore the importance of investigating epithelial-to-mesenchymal transition as a tissue-specific process to identify the most suitable markers acting as potential indicators of disease aggressiveness and therapeutic responsiveness. Full article

Sanghuang (Sanghuangporus sanghuang, SS) is a medicinal fungus with multiple pharmacological effects, including antioxidant, anti-inflammatory, immune-boosting, and anti-cancer activities. 5-fluorouracil (5-FU) is a commonly used chemotherapeutic agent for the treatment of colorectal cancer. It primarily exerts its antitumor effect by inhibiting DNA and RNA synthesis, leading to cell apoptosis. However, it frequently induces adverse effects These issues limit the clinical application of 5-FU. This research aims to determine the potential of SS as a therapeutic agent in reducing 5-FU-induced intestinal mucositis in a mouse model. The results indicated that 5-FU administration significantly increased diarrhea severity, reduced colon length, caused small intestinal villus atrophy, disrupted intestinal architecture, led to insufficient crypt cell proliferation, and resulted in weight loss. It also significantly upregulated inflammatory responses, apoptosis, oxidative stress, and epithelial–mesenchymal transition (EMT) pathways, and disrupted the integrity of intestinal mucosal tight junction, while elevating pro-inflammatory cytokines and reducing antioxidant capacity. However, SS significantly ameliorating alleviating the adverse impacts of the chemotherapeutic agent on the intestinal mucosa. In conclusion, this investigation provides the first evidence of the protective effects of SS on 5-FU-induced mucositis. These findings suggest SS as a potential therapeutic application, offering a promising strategy for reducing the adverse effects of 5-FU chemotherapy and improving the treatment and quality of life for colorectal cancer patients. Full article

Enterotoxigenic Bacteroides fragilis (ETBF) is an intestinal bacterium that secretes the metalloprotease Bacteroides fragilis toxin (BFT), which induces E-cadherin cleavage and interleukin-8 secretion in human intestinal epithelial cell lines. ETBF-induced E-cadherin cleavage is proposed to be the underlying reason for the promotion of colitis in ETBF-infected mice. However, a BFT-responsive murine cell line has not yet been reported. In the current study, we report that the mouse colonic epithelial cell line CMT93 undergoes E-cadherin ectodomain cleavage, cell rounding, and proliferation in response to BFT treatment. The amino acid sequence of the putative cleavage site of E-cadherin is identical in both BFT-responsive (CMT93) and BFT-nonresponsive (MSIE, CT26, YAMC, and B16) cell lines, suggesting that the E-cadherin amino acid sequence is not responsible for this observation. After E-cadherin ectodomain cleavage, the membrane-bound intracellular E-cadherin domain underwent cleavage by γ-secretase and was subsequently degraded by the proteasome. Moreover, BFT induced the secretion of two chemokines (LIX and KC) and the formation of soluble TNFR1 in the CMT93 cell line. The identification of a BFT-responsive murine cell line may be used to elucidate the mechanism of ETBF pathogenesis in ETBF murine infection models. Full article

Although it has been shown that the tumor extracellular matrix (ECM) may sustain the cancer stem cell (CSC) niche, its role in the modulation of CSC properties remains poorly characterized. To elucidate this, paired tumor and adjacent normal mucosa, derived from colon cancer patients’ surgical resections, were decellularized and recellularized with two distinct colon cancer cells, HT-29 or HCT-15. Methods: The matrix impact on cancer stem cell marker expression was evaluated by flow cytometry and qRT-PCR, while transforming growth factor-β (TGF-β) secretion and matrix metalloprotease (MMP) activity were quantified by ELISA and zymography. Results: In contrast to their paired normal counterparts, the tumor decellularized matrices enhanced HT-29 expression of the pluripotency and stemness genes NANOG (p = 0.0117), SOX2 (p = 0.0156), and OCT4 (p = 0.0312) and of the epithelial-to-mesenchymal transition (EMT)-associated transcription factor SNAI1 (p = 0.0156). Notably, no significant differences were found in the expression of SLUG or TGFB on HT-29 or of the six transcripts on HCT-15 cells. HT-29 mRNA alterations were followed by enhanced expression of the stemness-associated receptors cluster of differentiation 44 (CD44), CD133, and CD166 (p = 0.0078), the secretion of TGF-β (p = 0.0286), and MMP-2 (p = 0.0081) and MMP-9 (p = 0.0402) proteolysis. To infer the clinical relevance of these findings, we assessed cohort databases and evidenced that patients expressing higher levels of the four stemness-associated genes (NANOG/SOX2/OCT4/SNAI1) had worse overall survival. This study demonstrates that normal and tumor matrices harbor different stemness potential and suggest patient-derived decellularized matrices as an excellent three-dimensional (3D) model to unveil stemness signatures, appointing candidates for future therapeutic strategies. Full article