3-Aminobenzamide Prevents Concanavalin A-Induced Acute Hepatitis by an Anti-inflammatory and Anti-oxidative Mechanism.

BACKGROUND AND AIMS: Concanavalin A is known to activate T cells and to cause liver injury and hepatitis, mediated in part by secretion of TNFα from macrophages. Poly(ADP-ribose) polymerase-1 (PARP-1) inhibitors have been shown to prevent tissue damage in various animal models of inflammation. The objectives of this study were to evaluate the efficacy and mechanism of the PARP-1 inhibitor 3-aminobenzamide (3-AB) in preventing concanavalin A-induced liver damage. METHODS: We tested the in vivo effects of 3-AB on concanavalin A-treated mice, its effects on lipopolysaccharide (LPS)-stimulated macrophages in culture, and its ability to act as a scavenger in in vitro assays. RESULTS: 3-AB markedly reduced inflammation, oxidative stress, and liver tissue damage in concanavalin A-treated mice. In LPS-stimulated RAW264.7 macrophages, 3-AB inhibited NFκB transcriptional activity and subsequent expression of TNFα and iNOS and blocked NO production. In vitro, 3-AB acted as a hydrogen peroxide scavenger. The ROS scavenger N-acetylcysteine (NAC) and the ROS formation inhibitor diphenyleneiodonium (DPI) also inhibited TNFα expression in stimulated macrophages, but unlike 3-AB, NAC and DPI were unable to abolish NFκB activity. PARP-1 knockout failed to affect NFκB and TNFα suppression by 3-AB in stimulated macrophages. CONCLUSIONS: Our results suggest that 3-AB has a therapeutic effect on concanavalin A-induced liver injury by inhibiting expression of the key pro-inflammatory cytokine TNFα, via PARP-1-independent NFκB suppression and via an NFκB-independent anti-oxidative mechanism.

Effects of Helicobacter Pylori Colonization/Infection on the Metabolic Profile of Obese Persons Undergoing Sleeve Gastrectomy Surgery for Weight Reduction.

BACKGROUND: Helicobacter pylori (HP) infection of the gastric mucosa may be involved in the development of insulin resistance (IR). OBJECTIVES: To investigate the association between HP status in stomach biopsies and weight reduction in patients who underwent laparoscopic sleeve gastrectomy (LSG). METHODS: In this retrospective analysis of medical charts, all patients who underwent LSG for weight reduction and had at least 1 year of follow-up were included. HP status was ascertained by two to four biopsies of the removed stomach. RESULTS: The study group comprised 70 patients; their mean age was 45.9 ± 11.9 years and 31.9% were males. Fourteen patients (20%) tested positive for HP colonization in gastric mucosa. HP status was not associated with age or smoking status. No difference was noted in the rate of diabetes mellitus (DM) or hypertension, but patients with HP had lower rates of hyperlipidemia (0 vs. 29 patients, 52%, P < 0.001). Patients lost an average of 10.5 kg/m2 after 12 months of follow-up, and no difference was noted between HP-positive and HP-negative patients. The rate of DM control was also similar between HP-positive and HP-negative patients at baseline (33.3 vs. 29.4, P = NS) and at 12 months of follow-up (70% vs. 50%, P = NS). CONCLUSIONS: HP status was not associated with changes in metabolic profiles and co-morbidity status, or in the efficacy of LSG.