Role of cyclooxygenase-2 in intestinal injury in neonatal rats

Brucea javanica oil alleviates intestinal mucosal injury induced by chemotherapeutic agent 5-fluorouracil in mice

Background: Brucea javanica (L.) Merr, has a long history to be an anti-dysentery medicine for thousand of years, which is commonly called "Ya-Dan-Zi" in Chinese. The common liquid preparation of its seed, B. javanica oil (BJO) exerts anti-inflammatory action in gastrointestinal diseases and is popularly used as an antitumor adjuvant in Asia. However, there is no report that BJO has the potential to treat 5-Fluorouracil (5-FU)-induced chemotherapeutic intestinal mucosal injury (CIM). Aim of the study: To test the hypothesis that BJO has potential intestinal protection on intestinal mucosal injury caused by 5-FU in mice and to explore the mechanisms. Materials and methods: Kunming mice (half male and female), were randomly divided into six groups: normal group, 5-FU group (5-FU, 60 mg/kg), LO group (loperamide, 4.0 mg/kg), BJO group (0.125, 0.25, 0.50 g/kg). CIM was induced by intraperitoneal injection of 5-FU at a dose of 60 mg/kg/day for 5 days (from day 1 to day 5). BJO and LO were given orally 30 min prior to 5-FU administration for 7 days (from day 1 to day 7). The ameliorative effects of BJO were assessed by body weight, diarrhea assessment, and H&E staining of the intestine. Furthermore, the changes in oxidative stress level, inflammatory level, intestinal epithelial cell apoptosis, and proliferation, as well as the amount of intestinal tight junction proteins were evaluated. Finally, the involvements of the Nrf2/HO-1 pathway were tested by western blot. Results: BJO effectively alleviated 5-FU-induced CIM, as represented by the improvement of body weight, diarrhea syndrome, and histopathological changes in the ileum. BJO not only attenuated oxidative stress by upregulating SOD and downregulating MDA in the serum, but also reduced the intestinal level of COX-2 and inflammatory cytokines, and repressed CXCL1/2 and NLRP3 inflammasome activation. Moreover, BJO ameliorated 5-FU-induced epithelial apoptosis as evidenced by the downregulation of Bax and caspase-3 and the upregulation of Bcl-2, but enhanced mucosal epithelial cell proliferation as implied by the increase of crypt-localized proliferating cell nuclear antigen (PCNA) level. Furthermore, BJO contributed to the mucosal barrier by raising the level of tight junction proteins (ZO-1, occludin, and claudin-1). Mechanistically, these anti-intestinal mucositis pharmacological effects of BJO were relevant for the activation of Nrf2/HO-1 in the intestinal tissues. Conclusion: The present study provides new insights into the protective effects of BJO against CIM and suggests that BJO deserves to be applied as a potential therapeutic agent for the prevention of CIM.

Stem cell therapy as a promising strategy in necrotizing enterocolitis

Necrotizing enterocolitis (NEC) is a devastating gastrointestinal disease that affects newborns, particularly preterm infants, and is associated with high morbidity and mortality. No effective therapeutic strategies to decrease the incidence and severity of NEC have been developed to date. Stem cell therapy has been explored and even applied in various diseases, including gastrointestinal disorders. Animal studies on stem cell therapy have made great progress, and the anti-inflammatory, anti-apoptotic, and intestinal barrier enhancing effects of stem cells may be protective against NEC clinically. In this review, we discuss the therapeutic mechanisms through which stem cells may function in the treatment of NEC.

Low-dose cyclooxygenase-2 (COX-2) inhibitor celecoxib plays a protective role in the rat model of neonatal necrotizing enterocolitis

This study aims to investigate the effects of the cyclooxygenase-2 (COX-2) inhibitor celecoxib on neonatal necrotizing enterocolitis (NEC) in rats. After treatment with a low dose of celecoxib (0.5, 1, or 1.5 mg/kg), pathological changes in the ileum and the levels of oxidative stress and inflammatory factors in NEC rats were compared. Enzyme-linked immunosorbent assay (ELISA) was employed to detect inflammatory factors, terminal deoxyribonucleotidyl transferase (TdT)-mediated biotin-16-dUTP nick-end labeling (TUNEL) staining was employed to assess apoptotic epithelial cells in the ileum, and real-time quantitative polymerase chain reaction (qRT-PCR) and Western blotting were used to quantify gene and protein expression, respectively. The incidences of NEC rats in the 0.5, 1 and 1.5 mg/kg celecoxib groups were lower than in the model group (100%). Celecoxib improved the histopathology of the ileum in NEC rats. Moreover, low doses of celecoxib relieved oxidative stress and inflammation in NEC rats, as evidenced by decreased tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), total oxidation state (TOS), malondialdehyde (MDA) and oxidative stress index (OSI), as well as increased interleukin-10 (IL-10), total antioxidant status (TAS), superoxide dismutase (SOD) and glutathione peroxidase (GPx). With increasing celecoxib doses (0.5, 1, or 1.5 mg/kg), the amount of apoptotic epithelial cells in the ileum of NEC rats gradually declined and Caspase-3 expression was reduced. The low dose of the COX-2 inhibitor celecoxib ameliorated the histopathologic conditions of the ileum, alleviated oxidative stress and inflammation, and reduced apoptotic epithelial cells in NEC rats, thereby making it a potential therapy for NEC.

Evidence-Based Practices Reduce Necrotizing Enterocolitis and Improve Nutrition Outcomes in Very Low-Birth-Weight Infants

BACKGROUND

Necrotizing enterocolitis (NEC) is the most common gastrointestinal emergency in preterm infants. Survivors may suffer both short- and long-term morbidities. Current evidence suggests that the incidence of NEC can be reduced by standardizing the care delivery in addressing key risk factors including an altered gut microbiome, use of formula milk, hyperosmolar feeds, and unrestricted use of high-risk medications METHODS: Since 2014, the department has a workgroup who analyzed all cases of NEC within a month of diagnosis to identify preventable risk factors. Existing evidence-based quality improvement strategies were revised and new ones were implemented sequentially over the next 4 years. These strategies include (1) a standardized feeding protocol, (2) early initiation of enteral feeding using human milk, (3) optimization of the osmolality of preterm milk feeds using standardized dilution guidelines for additives, and (4) promotion of healthy microbiome by use of probiotics, early oral care with colostrum and by restricting high-risk medications and prolonged use of empirical antibiotics RESULTS: Baseline characteristics of the patients including sex, gestational age, and birth weight were similar during the study period. After implementing the evidence-based practices successively over 4 years, the incidence of NEC in very- low birth-weight (VLBW) infants dropped from 7% in 2014 to 0% (P < .001) in 2018. The duration of parenteral nutrition, use of central line, and days to full feeds were also reduced significantly (P < .05) CONCLUSION: Adopting evidence-based best practices resulted in a significant decrease in the incidence of NEC and improved the nutrition outcomes in VLBW infants.

Nesfatin-1 ameliorates oxidative bowel injury in rats with necrotizing enterocolitis: The role of the microbiota composition and claudin-3 expression

BACKGROUND AND PURPOSE

Ongoing high mortality due to necrotizing enterocolitis (NEC) necessitates the investigation of novel treatments to improve the outcome of the affected newborns. The aim was to elucidate the potential therapeutic impact of the nesfatin-1, a peptide with anti-inflammatory and anti-apoptotic effects in several inflammatory processes, on NEC-induced newborn rats.

MATERIALS AND METHODS

Sprague-Dawley pups were separated from their mothers, fed with a hyperosmolar formula and exposed to hypoxia, while control pups had no intervention. NEC-induced pups received saline or nesfatin-1 (0.2 μg/kg/day) for 3 days, while some nesfatin-1 treated pups were injected with capsaicin (50 μg/g) for the chemical ablation of afferent neurons. On the 4th day, clinical state and macroscopic gut assessments were made. In intestines, immunohistochemical staining of cycloxygenase-2 (COX-2), nuclear factor (NF)-κB-p65 (RelA), vascular endothelial growth factor (VEGF), claudin-3 and zonula occludens-1 (ZO-1) were performed, while gene expressions of COX-2, occludin, claudin-3, NF-κB-p65 (RelA) and VEGF were determined using q-PCR. In fecal samples, relative abundance of bacteria was quantified by q-PCR. Biochemical evaluation of oxidant/antioxidant parameters was performed in both intestinal and cerebral tissues.

RESULTS

Claudin-3 and ZO-1 immunoreactivity scores were significantly elevated in the nesfatin-1 treated control pups. Nesfatin-1 reduced NEC-induced high macroscopic and clinical scores, inhibited NF-κB-65 pathway and maintained the balance of oxidant/antioxidant systems. NEC increased the abundance of Proteobacteria with a concomitant reduction in Actinobacteria and Bacteroidetes, while nesfatin-1 treatment reversed these alterations. Modulatory effects of nesfatin-1 on microbiota and oxidative injury were partially reversed by capsaicin. Immunohistochemistry demonstrated that nesfatin-1 abolished NEC-induced reduction in claudin-3. Gene expressions of COX-2, NF-κB, occludin and claudin-3 were elevated in saline-treated NEC pups, while these up-regulated mRNA levels were not further altered in nesfatin-1-treated NEC pups.

CONCLUSION

Nesfatin-1 could be regarded as a potential preventive agent for the treatment of NEC.

Ginger (Zingiber officinale Roscoe) for the treatment and prevention of necrotizing enterocolitis

ETHNOPHARMACOLOGICAL RELEVANCE

Necrotizing enterocolitis (NEC) is the most important gastrointestinal emergency affecting especially preterm infants and causes severe morbidities and mortality. However, there is no cure. Oxidant stress, inflammation, apoptosis, as well as prematurity are believed to responsible in the pathogenesis of the disease. Ginger and its compounds have anti-inflammatory, antimicrobial, anti-oxidant properties and immunomodulatory, cytoprotective/regenerative actions.

AIM OF THE STUDY

This study aimed to evaluate the beneficial effects of ginger on the intestinal damage in an experimental rat model of NEC.

MATERIALS AND METHODS

Thirty newborn Wistar rats were divided into three groups: NEC, NEC + ginger and control in this experimental study. NEC was induced by injection of intraperitoneal lipopolysaccharide, feeding with enteral formula, hypoxia-hyperoxia and cold stress exposure. The pups in the NEC + ginger group were orally administered ginger at a dose of 1000 mg/kg/day. Proximal colon and ileum were excised. Histopathological, immunohistochemical (TUNEL for apoptosis, caspase 3 and 8) and biochemical assays including xanthine oxidase (XO), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), malonaldehyde (MDA) and myeloperoxidase (MPO), tumor necrosis factor-α (TNF-α), interleukin1β (IL-1β), and interleukin 6 (IL-6) activity were evaluated.

RESULTS

Compared with the NEC group, the rat pups in the NEC + ginger group had better clinical disease scores and weight gain (p < 0.05). Macroscopic evaluation, Histopathologic and apoptosis assessment (TUNEL, caspase 3 and 8) releaved that severity of intestinal damage were significantly lower in the NEC + ginger group (p < 0.05). The levels of TNF-α, IL-1β and IL-6 in the ginger treated group were significantly decreased (P < 0.05). The GSH-Px and SOD levels of the ginger treated group were significantly preserved in the NEC + ginger group (p < 0.05). The tissue XO, MDA and MPO levels of the NEC + ginger group were significantly lower than those in the NEC group (P < 0.05).

CONCLUSION

Ginger therapy efficiently ameliorated the severity of intestinal damage in NEC and may be a promising treatment option.