Effects of Apocynin and Natural Antioxidant from Spinach on Inducible Nitric Oxide Synthase and Cyclooxygenase‐2 Induction in Lipopolysaccharide‐Induced Hepatic Injury in Rat

Abstract

Abstract:The immunoreactivity of inducible nitric oxide synthase, and cyclooxygenase-2 was compared among groups of male Wistar rats comprising those injected with lipopolysaccharide following pretreatment with either natural antioxidant from spinach or the antioxidant apocynin, with lipopolysaccharide without pretreatment with antioxidants, with each of the two antioxidants alone, and untreated controls. The grade of staining of both inducible nitric oxide synthase and cyclooxygenase-2 increased with the severity of the inflammatory reaction in the lipopolysaccharide-treated animals, compared to the antioxidant-treated groups. Interpretation of the results of the immunostained tissues indicated that pretreatment with either antioxidant significantly (P∞0.05) attenuated the lipopolysaccharide-stimulated inducible nitric oxide synthase induction. Analysis of the cycloxygenase-2-stained liver samples indicated that the pretreatment with the natural antioxidant NAO significantly (P∞0.05) attenuated lipopolysaccharide-stimulated cycloxygenase-2 induction; whereas, in animals pretreated with apocynin, there was a trend of reduction in the cyclooxygenase-2 expression, but not statistically significant (P±0.05). The negative nitrotyrosine immunoreactivity of the lipopolysaccharide-related hepatic lesions may indicate that there was relatively low interaction between superoxide anions and nitric oxide to form peroxynitrite or that the expression levels of the nitrotyrosine were below the limit of detection. In all treatment groups a positive correlation (P∞0. 05, rΩ0.86) found between the inducible nitric oxide synthase and cyclooxygenase-2 scores suggests a strong relationship between these two parameters. The results indicate the possible therapeutic efficacy of NAO and apocynin in the prevention of liver damage related to clinical endotoxemia known to be associated with oxidative stress.

Synergistic activity between a spinach-derived natural antioxidant (NAO) and commercial antioxidants in a variety of oxidation systems

“…Its efficiency was tested and proven in a variety of biological systems in vivo and in vitro (Breitbart et al, 2001;Lomnitski et al, 2000aLomnitski et al, , 2000bLomnitski et al, , 2003Nyska et al, 2001Nyska et al, , 2003.…”

Slowing Tumorigenic Progression in TRAMP Mice and Prostatic Carcinoma Cell Lines Using Natural Anti-Oxidant from Spinach, NAO—A Comparative Study of Three Anti-Oxidants

“…NAO has previously exhibited dramatic anti-inflammatory properties in lipopolysaccharide(LPS)-induced septic shock in rat and rabbit models (3,4,34,35). Anti-inflammatory compounds have been proven effective in preventing prostatic cancer development in transgenic TRAMP mice (57).…”

Redox protective potential of fruits and vegetables: A review

“…Spinach is known for its iron content, however, natural antioxidant mixture of spinach leaves has been shown to have antioxidative, antiproliferative and anti-inflammatory properties in biological systems [79]. Its antioxidant properties are due to presence of glucuronic acid derivatives of flavonoids, trans and cis isomers of p-coumaric acid and meso-tartrate derivatives of p-coumaric acid which were detected in aqueous extract of spinach [80].…”