Myrtle berry seed aqueous extract inhibits human neutrophil myeloperoxidase in vitro and attenuates acetic acid-induced ulcerative colitis in rats

Abstract

International audienceWe aimed in the present study to investigate the protective effect of a myrtle (Myrtus communis L.) berry seed aqueous extract (MBSAE) on acetic acid (AA)-induced colitis in rats as well as the mechanism implicated in this coli-protection. The use of the LC/MS technique allowed us to identify 18 phenolic compounds in the MBSAE. Secondly, we found that the MBSAE inhibited the luminol-amplified chemiluminescence of resting neutrophils and N-formyl-methionylleucyl-phenylalanine (fMLF) or phorbolmyristate acetate (PMA) stimulated neutrophils in a dose-dependent manner. The MBSAE had no effect on superoxide anions, but it inhibited H2O2 production in the cell free system stimulated with horseradish peroxidase (HRPO) and MPO release from the neutrophils. In vivo, the pre-treatment of rats with sulfasalazine (100 mg kg(-1)) and the MBSAE (25, 50, and 100 mg kg(-1)) significantly reduced AA-induced colonic mucosa lesions as well as histopathological changes. The MBSAE counteracted AA-induced lipid peroxidation and the depletion of the activity of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). We also found that the myrtle extract inhibited the increase of the plasma scavenging activity (PSA) and preserved the content of non-enzymatic antioxidants such as sulfhydryl groups (-SH) and reduced glutathione (GSH). More importantly, acetic acid administration increased colonic hydrogen peroxide (H2O2), free iron and calcium levels, while the MBSAE pre-treatment reversed all intracellular mediator perturbations. In conclusion, our data suggests that the MBSAE exerted a potential protective effect against AA-induced injury and oxidative stress in the rat colon. This coli-protection might be related in part to its antioxidant and ROS scavenging activities or by negatively regulating Fenton reaction components such as H2O2 and free iron, which are known to lead to cytotoxicity mediated by intracellular calcium deregulation

Protective Effects of Honey and Spirulina Platensis on Acetic Acid-Induced Ulcerative Colitis in Rats

“…Interactions between environmental factors and genetic and immune responses may account for the overproduction of free radicals, reactive oxygen species (ROS), and proinflammatory cytokines, which start inflammatory responses to involve in the pathogenesis of IBD. An imbalance between oxidant/antioxidant systems results in oxidative stress and inflammatory cascade (4)(5)(6).…”

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“…The BM free iron chelation and H2O2 scavenging activities can be attributed to its richness in antioxidants molecules and the improving of these activities by myrtle adding is may be due to the phenolic compounds allowing to H2O2 reduction to water (Rice-Evans et al, 1997). The same mechanism was previously described in the small intestines (Jabri et al, 2016) and in the colon (Jabri et al, 2015).…”

“…Glutathione regulates the ROS level in the cells; it acts as a growth factor, an antiapoptotic factor in leukocytes and is involved in the cytokine secretion regulation (Sprietsma 1999). The addition of myrtle in bovine milk improved its antioxidant power, in fact a broad range of phenolic compounds has been identified in the myrtle berries (Messaoud and Boussaid 2011) and seeds (Jabri et al, 2015). Polyphenols are the most abundant antioxidants in our diets.…”

“…Similarly, lactoferrin, a whey protein has been shown to provide anti-inflammatory effects against colitis induced by dextran sulphate sodium (DSS) in mice (Haversen et al, 2003). More importantly, supplementation myrtle berries to milk improves its anti-inflammatory properties, seen the wealth of myrtle berries of chemical compounds known by their anti-ulcer and antiinflammatory effects (Jabri et al, 2015;Messaoud and Boussaid 2011;Sumbul et al, 2010). In this context several studies have shown the importance of fruit supplementation to dairy products in their improvement much as functional beverages (Zulueta et al, 2007;Cilla et al, 2012;Zulueta et al, 2007).…”

“…Ulcerative colitis was induced according to the procedures described by Jabri et al (2015). Briefly, animals were fasted for 24 h with free access to water and colitis was induced by the infusion of acetic acid (3% v/v, 5 mL/kg b.w.)…”