Inhibition of ENNG-Induced Pyloric Stomach and Small Intestinal Carcinogenesis in Mice by High Temperature- and Pressure-Treated Garlic

Abstract

High temperature-and pressure-treated garlic (HTPG) has been shown to have enhanced antioxidative activity and polyphenol contents. Previously, we reported that HTPG inhibited 1,2-dimethylhydrazine-induced mucin depleted foci (premalignant lesions) and O 6 -methylguanine DNA adduct formation in the rat colorectum. In the present study, we investigated the modifying effects of HTPG on N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG)-induced pyloric stomach and small intestinal carcinogenesis in mice. Male C57BL/6 mice were given ENNG (100 mg/l) in drinking water for the first 4 weeks, then a basal diet or diet containing 2% or 5% HTPG for 30 weeks. The incidence and multiplicity of pyloric stomach and small intestinal (duodenal and jejunal) tumors in the 2% HTPG group (but not in the 5% HTPG group) were significantly lower than those in the control group. Cell proliferation of normal-appearing duodenal mucosa was assessed by MIB-5 immunohistochemistry and shown to be significantly lower with 2% HTPG (but again not 5% HTPG) than in controls. These results in dicate that HTPG, at 2% in the diet, inhibited ENNG-induced pyloric stomach and small intestinal (especially duodenal) tumorigenesis in mice, associated with suppression of cell proliferation.

Dietary Agents and Phytochemicals in the Prevention and Treatment of Experimental Ulcerative Colitis

“…The inflammatory pathway in UC involves ubiquitous expression of proinflammatory eukaryotic transcription factors [activator protein (AP)-1 and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB)],[45] which leads to the production of pro-inflammatory cytokines like tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-1β, with T-helper (Th)-17 cytokines such as IL-23 and IL-17 predominating, and a concomitant decrease in the anti-inflammatory cytokines and proteins. [67] This surge in pro-inflammatory cytokines is followed by an increase in the production of cyclooxygenase (COX)-2, inducible nitric oxide synthase (iNOS), myeloperoxidase,[8] and signal transducer and activator of transcription[9] -3,[56] which further increases inflammation and leads to oxidative stress[10] and a concomitant decrease in the level of antioxidants. [1011] All these events lead to an increase in cell inflammation, infiltration of the immune cells, especially the neutrophils, and culminate into epithelial cell damage and colonic barrier dysfunction.…”

“…Administration of the polyphenol EGCG also led to a decrease in the levels of COX-2,[58] myeloperoxidase,[85355] and intercellular adhesion molecule-1 (ICAM)-1,[53] and rectified the distorted actin cytoskeleton in the colonic tissue. [52] These beneficial effects of EGCG were associated with a significant reduction of NF-κB and AP-1 activation.…”

Inhibition of Azoxymethane-induced Colorectal Aberrant Crypt Foci in Mice Fed a High-fat Diet by Pleurotus eryngii (Eringi) and Hypsizygus marmoreus (Bunashimeji)

“…Ki-67 was stained to compare the positivity rate. Epithelial proliferation of the colon was determined by a slight modification of the method of Katsuki et al (2006) and Kaneko et al (2012). Briefly, the sections were retrieved in an autoclave in citrate buffer (pH 6.0) for 20 min at 120°C.…”