The inhibitory effect of flavonoids on interleukin-8 release by human gastric adenocarcinoma (AGS) cells infected with cag PAI (+) Helicobacter pylori.

INTRODUCTION

It is well known that the presence of Helicobacter pylori in the stomach induces gastritis and causes an immune response. Exposure of gastric epithelial cell lines to this germ induces the secretion of interleukin-8 (IL-8), which is a potent PMN-activating chemotactic cytokine. Interleukin-8 is usually elevated in gastric biopsy samples of patients with H. pylori-associated gastritis and significantly increases in the supernatant of in vitro cultivated biopsy samples of gastric mucosa with active H. pylori gastritis. Interleukin-8 is an activating factor for leucocytes and other pro-inflammatory factors, free radicals, and proteolytic enzymes. That is why natural compounds potentially useful in therapy are still investigated - among them flavonoids. They reveal anti-oxidative and anti-inflammatory activities and significantly inhibit the gastric mucosa damage.

THE AIM OF THE STUDY: Was the estimation of the anti-inflammatory effects of flavonoids on H. pylori-induced activation of human gastric adenocarcinoma cells (AGS). After infection of AGS cells by cag PAI (+) H. pylori in vitro, secretion of IL-8, effects of flavonoids on viability of AGS cells, and effects of flavonoids on increase of H. pylori were determined. Such flavones as chrysin, quercetin, kaemferide, flavanone, galangin, and kaempferol were examined.

RESULTS

This study has shown an inhibitory effect of flavonoids on the release of IL-8 through infected AGS cells (except chrysin), and no toxic effects to AGS cells were observed. Galangin revealed antibacterial effects against H. pylori. Flavonoids limit the inflammatory process through the inhibition of IL-8 release in infected AGS cells with H. pylori. The strongest inhibitor of IL-8 was galangin.