Genome-wide DNA methylation changes after 24 hours at high altitude.

Area of Science:

• Environmental Epigenetics
• Human Physiology
• Molecular Biology

Background:

• High altitude induces hypobaric hypoxia, a stressor with known physiological responses.
• The impact of acute hypoxia on epigenetic modifications, specifically DNA methylation, is not well understood.

Purpose of the Study:

• To investigate DNA methylation patterns following acute exposure to high altitude.
• To identify specific genes and pathways affected by short-term hypoxic conditions.

Main Methods:

• Peripheral blood mononuclear cells (PBMCs) were collected from 12 healthy adults at sea level and after 24 hours at 3800 m.
• DNA methylation was analyzed using the Illumina MethylationEPIC array.

Main Results:

• Over 58,000 differentially methylated positions were identified, with a majority showing increased methylation (hypermethylation) at high altitude.
• Differentially methylated sites were enriched in hypoxia-inducible factor (HIF) pathway-related genes, including Notch and AKT1 signaling.
• Key pathways implicated included calcium regulation, DNA damage repair, zinc finger proteins, glucose metabolism, and erythropoiesis.

Conclusions:

• Acute high-altitude exposure induces significant, global DNA hypermethylation.
• DNA methylation dynamically responds to environmental hypoxia, potentially mediating cellular responses.
• Epigenetic changes are linked to critical biological processes affected by hypoxia, such as calcium regulation and HIF signaling.