Butyrate Protects Mice from Clostridium difficile-Induced Colitis through an HIF-1-Dependent Mechanism.

Antibiotic-induced dysbiosis is a key factor predisposing intestinal infection by Clostridium difficile. Here, we show that interventions that restore butyrate intestinal levels mitigate clinical and pathological features of C. difficile-induced colitis. Butyrate has no effect on C. difficile colonization or toxin production. However, it attenuates intestinal inflammation and improves intestinal barrier function in infected mice, as shown by reduced intestinal epithelial permeability and bacterial translocation, effects associated with the increased expression of components of intestinal epithelial cell tight junctions. Activation of the transcription factor HIF-1 in intestinal epithelial cells exerts a protective effect in C. difficile-induced colitis, and it is required for butyrate effects. We conclude that butyrate protects intestinal epithelial cells from damage caused by C. difficile toxins via the stabilization of HIF-1, mitigating local inflammatory response and systemic consequences of the infection.

Conjugated linoleic acid prevents damage caused by intestinal mucositis induced by 5-fluorouracil in an experimental model.

BACKGROUND: Studies have showed the protective effects of conjugated linoleic acid (CLA) on intestinal epithelium, modulating host immune and inflammatory responses on intestinal diseases. OBJECTIVE: To evaluate the preventive effects of CLA on the intestinal mucositis induced by 5-FU in a murine model. METHODS: Sixty-four BALB/c mice were randomly divided into four groups: Control (CTL), fed a standard chow diet; CLAs, fed a diet supplemented with CLA; Mucositis (5-FU), fed a standard chow diet and underwent mucositis induction and CLAs 5-FU, fed a diet supplemented with CLA and underwent mucositis induction. Mucositis was induced by intraperitoneal injection of 300 mg/kg 5-FU. After 72 h, the animals were euthanized and intestinal permeability, bacterial translocation, inflammatory mediators, and intestinal histology were evaluated. RESULTS: Mice in the CLAs 5-FU group showed reduced weight loss compared to those in the 5-FU group (p < 0.005). Furthermore, the results also showed that the treatment with CLA reduced intestinal permeability, bacterial translocation, and biomarkers of inflammatory response besides minor damage to ZO-1 and occludin with maintenance of the integrity of the intestinal epithelium and a favorable balance between the inflammatory and regulatory cytokines. CONCLUSION: This study suggests that CLA reduced the adverse effects from 5-FU administration on the intestinal mucosa.

Intestinal toxicity evaluation of long-circulating and pH-sensitive liposomes loaded with cisplatin.

Cisplatin (CDDP) is a chemotherapeutic agent widely used in several anticancer protocols for instance head and neck, testicle, ovarian, lung and peritoneal carcinomatosis. According to the literature, the use of CDDP is associated with several side effects; among them, we highlighted the mucositis. CDDP, when administered by IP, promoted significant intestinal epithelium alterations in an experimental model. Our research group has proposed that the incorporation of CDDP into long-circulating and pH-sensitive liposomes (SpHL-CDDP) could help to overcome some side effects induced by this drug. Thus, we evaluated signs of intestinal toxicity 24h and 72h after the administration of a single i.p dose of free CDDP or SpHL-CDDP to healthy Swiss mice. Twenty-four hours after administration of free CDDP, the mice showed signs of intestinal toxicity, principally weight loss, increased intestinal permeability associated with a decrease in expression of tight junctions, and histological damage with the presence of inflammatory infiltrates and activation of ERK1/2 and NF-κB. These changes persisted after 72h. While signs of intestinal toxicity were also observed 24h after administration of SpHL-CDDP, after 72h body weight and intestinal permeability of mice in this group were similar to those of mice in the control group. In comparison with the free CDDP treatment group, 72h after treatment mice in the SpHL-CDDP group showed better histological parameters, lower levels of inflammatory infiltrate with increased IL-10 and IgA levels, and less activation of caspase-3, ERK1/2 and NF-κB. These differences could account for the recovery of the intestinal epithelium observed in mice treated with SpHL-CDDP but not in mice treated with free CDDP. In conclusion, here we show that encapsulation of CDDP in SpHL lessens intestinal damage and that, as such, SpHL-CDDP is a promising candidate for clinical use.

Effect of Conjugated Linoleic Acid-enriched Butter After 24 hours of Intestinal Mucositis Induction.

Mucositis is the most common side effect due to chemotherapy or radiotherapy. It refers to the inflammation of intestinal mucous membranes, and it is associated with complications such as diarrhea, weight loss, and increased intestinal permeability (IP). This study was designed to evaluate the effect of diet containing conjugated linoleic acid (CLA)-enriched butter on intestinal damage and inflammatory response after 24 h of 5-fluorouracil (5-FU)-induced mucositis. Mice were divided into four groups: CTL; CLA; 5-FU, and CLA 5-FU, and they were fed for 31 days. On the 30th experimental day, mucositis was induced by unique injection of 300 mg/kg of 5-FU. After 24 h (31st experimental day), IP was evaluated; ileum and fecal material were collected to determine cytokine level and myeloperoxidase (MPO) activity and secretory immunoglobulin A (sIgA). The 5-FU group showed an increase in IP and MPO activity (CTL vs. 5-FU: P < 0.05). Additionally, increased levels of IP and MPO were observed in CLA 5-FU group compared to those in the test groups (P < 0.05). Animals in the CLA 5-FU group showed reduced concentrations of sIgA (CTL vs. CLA 5-FU: P < 0.05). CLA-enriched butter exacerbating the 5-FU-induced intestinal damage. Safety concerns regarding the use of CLA require further investigation.