Mitochondrial DNA Haplogroup Related to the Prevalence of Helicobacter pylori

Area of Science:

• Mitochondrial biology
• Infectious diseases
• Genetics

Background:

• Mitochondria are vital organelles involved in energy production, metabolism, calcium homeostasis, and apoptosis.
• Bacteria, including Helicobacter pylori (H. pylori), exploit host cell mitochondria to promote infection.
• The role of mitochondrial DNA (mtDNA) polymorphism, specifically haplogroups, in H. pylori infection remains understudied.

Purpose of the Study:

• To investigate the association between mitochondrial haplogroups and H. pylori prevalence.
• To determine if mitochondrial haplogroups influence the severity of H. pylori-induced cellular damage.
• To analyze the accumulation and location of mtDNA mutations in H. pylori-positive individuals.

Main Methods:

• Identification of seven mtDNA haplogroups in H. pylori-positive subjects.
• Comparative analysis of haplogroup frequencies between H. pylori-positive and negative populations.
• Assessment of fibroblast apoptosis and mitochondrial respiration post-H. pylori infection.
• Analysis of mtDNA mutation accumulation and distribution in different age groups and infection statuses.

Main Results:

• Haplogroup B was more frequent, and haplogroup D less frequent in H. pylori-positive individuals.
• Fibroblasts with high-frequency haplogroups showed increased apoptosis and reduced mitochondrial respiration after H. pylori infection.
• mtDNA mutations accumulated more in H. pylori-positive individuals, particularly in RNA genes and protein-coding regions.

Conclusions:

• Mitochondrial haplogroups are associated with H. pylori prevalence and infection outcomes.
• H. pylori infection can lead to increased mitochondrial damage, influenced by host mtDNA haplogroup.
• mtDNA mutations may play a role in the pathogenesis of gastric diseases caused by H. pylori.