Tiron ameliorates acetic acid-induced colitis in rats: Role of TGF-ß/EGFR/PI3K/NF-κB signaling pathway.

BACKGROUND: Ulcerative colitis (UC), an ongoing inflammatory disorder of the colon, is marked by persistent mucosal surface irritation extending from the rectum to the near-proximal colon. Tiron is a synthetic analogue of vitamin E which is known to have antioxidant and anti-inflammatory effects in various animal models, so the goal of this study was to find out whether Tiron had any preventive impacts on UC inflicted by acetic acid (A.A) exposure in rats. METHOD: Tiron (235 and 470 mg/kg) was administered intra-peritoneally for 2 weeks, and A.A (2 ml, 3 % v/v) was injected intra-rectally to cause colitis. Colon tissues and blood samples were then collected for measurement of various inflammatory and oxidative stress biomarkers. RESULTS: Tiron administration significantly diminished lactate dehydrogenase (LDH), C-reactive protein (CRP), colon weight, and the weight/length ratio of the colon as compared to A.A-injected rats. Additionally, Tiron attenuated oxidative stress biomarkers. Tiron also enforced the levels of Glucagon-like peptide-1 (GLP-1) and trefoil factor-3 (TFF-3), while it greatly lowered the expression of nuclear factor kappa B (NF-κB), interleukin-6 (IL-6), interferon-γ (IFN-γ), and transforming growth factor-1(TGF-ß1), phosphorylated epidermal growth factor receptor (P-EGFR), phosphatidylinositol-3-kinase (PI3K) and protein kinase B (AKT) expression in colonic cellular structures. Furthermore, colonichistopathologic damages, revealed by hematoxylin and eosin (H&E) and Alcian Blue stain, were significantly decreased upon Tiron administration. CONCLUSION: Tiron prevented A.A-induced colitis in rats via modulating inflammatory pathway TGF-ß1/P-EGFR/PI3K/AKT/NF-κB, alongside managing the oxidant/antioxidant equilibrium, and boosting the reliability of the intestinal barrier.

Eicosapentaenoic acid mitigates ulcerative colitis-induced by acetic acid through modulation of NF-κB and TGF-ß/ EGFR signaling pathways.

BACKGROUND: Ulcerative colitis (UC) is a chronic mucosal inflammation of the large intestine that mostly affects the rectum and colon. The absence of safe and effective therapeutic agents encourages the discovery of novel therapeutic agents to effectively treat UC and its complications. The purpose of this research was to examine the protective impact of Eicosapentaenoic acid (EPA) in rats with UC induced by acetic acid (AA). METHOD: AA (2 ml, 3 % v/v) was injected intrarectally to cause UC. Before administering AA, EPA (300 and 1000 mg/kg) was given orally for 28 days. RESULTS: EPA inhibited AA-induced UC by enhancing colonic histopathological changes like inflammation, goblet cell loss, glandular hyperplasia and mucosal ulceration, concomitant with a reduction in colon weight, colon weight/length ratio, C-reactive protein (CRP), and serum lactate dehydrogenase (LDH). EPA also effectively restored the imbalance between oxidants and antioxidants caused by AA. In addition, EPA increased the levels of trefoil factor-3 (TFF-3) and glucagon-like peptide-1 (GLP-1), while significantly reducing the expression of nuclear factor kappa B (NF-κB), interferon-γ (IFN-γ), and interleukin-6 (IL-6), transforming growth factor-1(TGF-ß1), and phosphorylated epidermal growth factor receptor (P-EGFR), phosphatidylinositol-3-kinase (PI3K) and protein kinase B (AKT) expression in colonic tissues. CONCLUSION: EPA inhibited AA-induced UC in rats by modulating the TGF-ß/P-EGFR and NF-κB inflammatory pathways, regulating the oxidant/antioxidant balance, and enhancing the colon barrier integrity.