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Clostridioides difficile, a spore-forming anaerobic bacterium, is the primary cause of hospital antibiotic-associated diarrhea. Key virulence factors, toxins A (TcdA) and B (TcdB), significantly contribute to C. difficile infection (CDI). Yet, the specific impact of these toxins, particularly on enteric glial cells (EGCs), still needs to be fully understood. This study examines the role of the transient receptor potential vanilloid 4 (TRPV4), a calcium-permeable channel, in the inflammatory response and apoptosis of EGCs induced by TcdA and TcdB and evaluates TRPV4 expression in the cecum and colon of infected mice. EGCs were treated with TcdA (50ng/mL) or TcdB (1ng/mL) for 18 h, with or without the TRPV4 antagonist RN-1734 (100 µM), to assess TRPV4 gene and protein levels, inflammatory markers, and cell death. C. difficile infected mice were euthanized on day 3 post-infection for TRPV4 expression in the cecum and colon. Findings reveal that EGCs naturally express TRPV4, increasing its expression by TcdA and TcdB exposure. CDI significantly upregulates TRPV4 in the cecum and colon's submucosal and myenteric plexus regions. TRPV4 mediates TNF-α release in EGCs and is partially involved in the increase in IL-6 gene expression triggered by these toxins. Our results highlight TRPV4's role in triggering EGC apoptosis via caspase 3 activation and inhibiting the reduction of Bcl-2, an anti-apoptotic protein in EGCs caused by C. difficile toxins. These results highlight TRPV4's significant role in CDI pathogenesis and its potential as a therapeutic target to counteract the detrimental effects of C. difficile toxins on enteric glia., Competing Interests: Declarations. Ethics approval: The study’s experimental protocol received approval from the Ethics of Animal Experiments Committee at the University of Virginia (Protocol number 4096). Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Background: Evaluate the impact of Spondias mombin L. juice (SM), alone and in combination with Lactobacillus acidophilus, in an experimental model of intestinal mucositis., Methods: Swiss mice were orally administered with saline, SM, or SM combined with L. acidophilus NRRL B-4495 at 1 × 10 9 colony-forming unit (CFU/mL) for 15 days before the induction of intestinal mucositis by a single intraperitoneal injection of 5-fluorouracil (5-FU) at 450 mg/kg. On the 18th day, following euthanasia, tissue samples were collected for histopathological examination. Jejunum tissues were analyzed for MUC-2 immunoexpression, concentrations of interleukin-1-beta (IL-1β), interleukin 6 (IL-6) and tumor necrosis factor (TNF)-α, and invertase activity., Key Results: 5-FU induced intestinal damage in all intestinal segments, and this damage involved villus blunting, flattened and vacuolated cells, crypt necrosis, inflammatory cell infiltration, and mucosa and submucosal edema compared to the control group. In contrast, SM or SM with L. acidophilus prevented these morphological alterations in all intestinal segments (p < 0.05). Both treatments reduced the intestinal concentration of IL-1 beta (p < 0.05), IL-6 (p < 0.05), and TNF-alpha (p < 0.05). Notably, the combination of SM and L. acidophilus, but not SM alone, prevented the 5-FU-induced decrease in invertase activity and mucin expression (p < 0.05). Furthermore, SM combined with L. acidophilus resulted in an increased population of lactic acid bacteria in feces on the 7th and 18th days. Combining SM with L. acidophilus also decreased fecal excretion of γ-Ergostenol and γ-sitosterol., Conclusions and Inferences: SM, alone and combined with Lactobacillus acidophilus demonstrated significant protective effects against 5-FU-induced intestinal mucositis, reducing inflammatory markers., (© 2024 John Wiley & Sons Ltd.)

Background and Aims: First-degree relatives of gastric cancer patients are at increased risk of developing gastric cancer. Increased oxidative stress, including lipid peroxidation, has been associated with gastric carcinogenesis. Whether first-degree relatives of gastric cancer patients have increased oxidative stress remains unknown. We aimed to compare oxidative stress in patients with gastric cancer, their first-degree relatives, and dyspeptic controls., Methods: A total of 155 patients undergoing upper endoscopy were prospectively enrolled, including 50 with gastric cancer, 49 first-degree relatives of gastric cancer patients, and 56 controls. Serum concentrations of malondialdehyde (MDA) and glutathione) and activities of superoxide dismutase (SOD) and catalase were measured. Multivariate analysis adjusting for sex, age, smoking status, and alcohol consumption was performed., Results: Lipid peroxidation, as measured by concentration of MDA (nmol/mL), was higher ( p = 0.04), and glutathione levels were lower ( p < 0.001) in the gastric cancer group compared to controls. There was no difference in the catalase activity among the groups. There was no difference in glutathione and MDA concentration or catalase activity between the different stages of gastric cancer based on the TNM classification. Relatives of gastric cancer patients had higher glutathione concentration ( μ mol/mL) compared to gastric cancer patients (262.5 vs. 144.6; p = 0.018), while there was no difference in MDA concentration. Catalase and superoxide dismutase activity were lower in the gastric cancer group (3.82 vs. 0.91; p < 0.001 and 1.04 vs. 0.6; p < 0.001) compared to their first-degree relatives. Interestingly, MDA concentration in the first-degree relative group was higher than in the control group (7.9 vs. 5.1; p = 0.03)., Conclusions: In this study, similarly to gastric cancer patients, their first-degree relatives were found to have increased oxidative stress compared to controls. Further studies are warranted to validate this observation and to better understand the role of oxidative stress as a possible biomarker in this population., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2021 Manuel B. Braga-Neto et al.)

Extra domain B of fibronectin (FN-EDB) is upregulated in the extracellular matrix during tissue remodeling and has been postulated as a potential biomarker for atherosclerosis, yet no systematic test for FN-EDB in plaques has been reported. We hypothesized that FN-EDB expression would intensify in advanced plaques. Furthermore, engineering of FN-EDB-targeted nanoparticles (NPs) could enable imaging/diagnosis and local delivery of payloads to plaques. Methods: The amount of FN-EDB in human atherosclerotic and normal arteries (ages: 40 to 85 years) was assessed by histological staining and quantification using an FN-EDB-specific aptide (APT FN-EDB ). FN-EDB-specific NPs that could serve as MRI beacons were constructed by immobilizing APT FN-EDB on the NP surface containing DTPA[Gd]. MRI visualized APT FN-EDB -[Gd]NPs administered to atherosclerotic apolipoprotein E-deficient mice in the brachiocephalic arteries. Analysis of the ascending-to-descending thoracic aortas and the aortic roots of the mice permitted quantitation of Gd, FN-EDB, and APT FN-EDB -[Gd]NPs. Cyanine, a model small molecule drug, was used to study the biodistribution and pharmacokinetics of APT FN-EDB -NPs to evaluate their utility for drug delivery. Results: Atherosclerotic tissues had significantly greater FN-EDB-positive areas than normal arteries ( P < 0.001). This signal pertained particularly to Type III ( P < 0.01), IV ( P < 0.01), and V lesions ( P < 0.001) rather than Type I and II lesions (AHA classification). FN-EDB expression was positively correlated with macrophage accumulation and neoangiogenesis. Quantitative analysis of T1-weighted images of atherosclerotic mice revealed substantial APT FN-EDB -[Gd]NPs accumulation in plaques compared to control NPs, conventional MRI contrast agent (Gd-DTPA) or accumulation in wild-type C57BL/6J mice. Additionally, the APT FN-EDB -NPs significantly prolonged the blood-circulation time (t 1/2 : ~ 6 h) of a model drug and increased its accumulation in plaques (6.9-fold higher accumulation vs. free drug). Conclusions: Our findings demonstrate augmented FN-EDB expression in Type III, IV, and V atheromata and that APT FN-EDB -NPs could serve as a platform for identifying and/or delivering agents locally to a subset of atherosclerotic plaques., Competing Interests: Competing Interests: O.C.F. declares financial interests in Selecta Biosciences, Tarveda Therapeutics, Placon Therapeutics, and Seer Biosciences.