Exploratory metabolomic analysis for identifying systemic signatures of Helicobacter pylori infection in children

Infections caused by the Gram-negative bacteria Helicobacter pylori (H. pylori) can result in gastritis, gastric or duodenal ulcers, and gastric cancer in humans. Examining quantitative changes in soluble biomarkers linked to H. pylori infection offers a promising approach to monitor the infection's progression, inflammatory response, and systemic effects.

This exploratory study aimed to analyze metabolomic biomarkers in the sera from children with dyspeptic symptoms infected with H. pylori and in control group of healthy children not exposed to H. pylori.

Biological samples: sera from 32 H. pylori-infected children - Hp (+) (female and male) with gastrointestinal symptoms (GIs) under the pediatric gastroenterological medical care; sera from 32 H. pylori uninfected children - Hp(-) (female and male) without GIs under general medical care. The H. pylori status in Hp(+) children was confirmed by ¹³C urea breath testing, the presence of serum anti-H. pylori IgG antibodies and gastroscopy-based tests (rapid urease test, histological examination of gastric tissue specimens for the presence of Helicobacter-like organisms-HLO and inflammation) while Hp(-) group was selected based on negative result of ¹³C urea breath test and the lack of serum anti-H. pylori IgG antibodies. Metabolomic profiling was performed using UPLC-QTOF/MS methods. Biomarkers significantly associated with H. pylori infection were identified using volcano plots and ROC analysis.

This exploratory study found 7 metabolites differentiating the serum samples of Hp(+) from Hp(-) children: carboxyethyl lysine - CEL (HMDB29447), gamma-Glutamylleucine (HMDB0011171), 13-HOTrE(y) hydroxylated and oxidized derivative of the omega-6 fatty acid arachidonic acid (HMDB0341541), 13-HODE (HMDB0004667), lauroylcarnitine (HMDB0002250), vitamin A (HMDB0000305) and 19_norandrosterone (HMDB0002697). These metabolites are associated with immune regulation, energy metabolism, lipid/fatty acid metabolism, lipid peroxidation, oxidative stress, and cell signaling, which may be linked with the pathogenesis of H. pylori infection in humans. However, this hypothesis needs to be confirmed based on direct immune measurements and longitudinal clinical outcomes.

This exploratory study delivered preliminary results on serum metabolomic profiling indicating differences between metabolites present in serum samples of H. pylori-infected and uninfected children. Further study is required for validation of proposed methodology and connecting the selected metabolites with H. pylori infection.