Infection with Helicobacterpylori increases apoptosis and the activity of the inducible form of NO synthase (;NOS) in gastric mucosa. However, whether NO triggers apoptosis or exerts a defensive role in such circumstances is unclear. The purpose of this work was therefore firstly to examine apoptotic responses of rat gastric mucosal cells subjected to long term exposure to exogenous NO in vitro, and secondly to determine whether induction of iNOS in vivo, by injection of lipopolysaccharide (LPS), caused similar changes to those obtained in vitro. The specific involvement of NO in effects of LPS were examined by using the selective iNOS inhibitor 1400W. Apoptotic activity was assessed by assay of caspase )-like activity and from fragmentation of DNA. Caspase Mike activity in isolated rat gastric mucosal cells at 24, 36, 48 and 60 h after plating of cells was substantially greater in the detached cells than in those that were attached to the culture plate. For both attached and detached cells the addition of the NO donor S-nitroso-Nacetyl-penicillamine (SNAP, 0.05 -2 mM) on plating produced a doserelated inhibition of caspase 3-like activity. Also at 60 h after plating the presence of SNAP (2 mM) prevented the appearance of DNA ladders (apoptotic DNA fragmentation) in cells which had detached from the plate. Injection of LPS (3 mg/kg, i.v.) to rats in vivo increased caspase 3-like activity measured 5 and 24 h later in rat gastric mucosa. Co-administration of the selective iNOS inhibitor, 1400 W (5 mglkg, i.v.), with LPS enhanced caspase 3-like activity above that with LPS alone. In conclusion data obtained both in vitro and zn vivo suggest that NO exerts an anti-apoptotic effect in rat gastric mucosa. VP5, 5'teminal small open reading frame (small ORF) of the A segment of the aquatic birnavirus (infectious pancreatic necroaia virus, IPNV) genome, encodes a 17 kDa non-structure protein.In recently, we reported that apoptosis induced by IPNV in a fish cell line. In the present study, we cloned and identified the VP5 and test its function. Compared the amino acids sequence of VP5 with well known Bcl-2 family member proteins that found the VP5 protein also contains the Bcl-2 homology (BH) domains BH1, BH2, BH3 and BH4 but the absence of the transmembrane region (TM). In addition VP5 stable clone either CHSE-VP5 or ZLE-VP5 also showed delay cell death and DNA internucleoso-ma1 cleavage during IPNV infection. O n the other hand, VP5 could both up-regulation of the survival factor Mcl-1 for enhance host survival and could to limit-regulate the specific viral proteins expression in early replication cycle. Taken together, these results suggest that the aquatic birnavirus may use a notable strategy with VP5 (a novel viral Bcl-2 family member protein) to against the host defense and enhance the progeny production.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.