Effect of Helicobacter pylori on NFKB1, p38α and TNF-α mRNA expression levels in human gastric mucosa

Abstract

<i>Helicobacter pylori</i> infects ~50% of the world population, causing chronic gastritis and other forms of cellular damage. The present study assessed the influence of <i>H. pylori</i> on the mRNA expression levels of nuclear factor-κB1 (<i>NFKB1</i>), <i>p38α</i> and tumor necrosis factor-α (<i>TNF-α</i>) in human gastric mucosa in a southern Brazilian population. Human gastric tissue was collected by upper endoscopy and <i>H. pylori</i> diagnosis was performed using a rapid urease test and histological analysis. Total RNA was extracted and purified for subsequent cDNA synthesis and analysis by quantitative polymerase chain reaction (qPCR). The gastric tissue samples were divided into four groups as follows: Normal, inactive chronic gastritis, active chronic gastritis and intestinal metaplasia. The <i>SDHA</i> gene was classified as the most stable when compared with <i>ACTB</i>, <i>GAPDH</i>, <i>B2M</i> and <i>HPRT1</i> genes, and was therefore selected as the reference gene for qPCR data normalization. TNF-α mRNA expression was significantly higher in samples that were positive for <i>H. pylori</i> and with active chronic gastritis. However, no difference was detected in the mRNA expression levels of <i>NFKB1</i> and <i>p38α</i> between the groups. The present study concluded that the presence of <i>H. pylori</i> is associated with <i>TNF-α</i> upregulation in human gastric mucosa, but had no effect on <i>NFKB1</i> and <i>p38α</i> mRNA expression levels.