TAK1-AMPK Pathway in Macrophages Regulates Hypothyroid Atherosclerosis

Area of Science:

• Cardiovascular Research
• Endocrinology
• Molecular Biology

Background:

• Hypothyroidism (HT) is linked to accelerated atherosclerosis (AS), a major cause of coronary artery disease (CAD).
• The effectiveness of current treatments for hypothyroid-associated AS is debated, highlighting the need for novel therapeutic strategies.
• Understanding the molecular mechanisms underlying HT-induced AS acceleration is crucial for reducing residual cardiovascular risk.

Purpose of the Study:

• To elucidate the mechanisms by which hypothyroidism accelerates atherosclerosis.
• To identify potential new therapeutic targets for hypothyroid AS.
• To decrease the residual risk of coronary artery disease in patients with hypothyroidism.

Main Methods:

• Collected peripheral venous blood samples from 20 patients across four groups: normal, HT, CAD, and HT+CAD.
• Utilized mRNA microarray and bioinformatics analysis to identify differentially expressed genes and pathways.
• Validated findings in ApoE knockout mice and Raw264.7 cell models.

Main Results:

• Identified 1218 differentially expressed genes and altered pathway activity between CAD and HT+CAD groups.
• Confirmed significantly decreased expression of MAP3K7 (transforming growth factor-β-activated kinase 1, TAK1) in patients with both HT and CAD.
• Observed reduced TAK1 expression and AMP-activated protein kinase (AMPK) phosphorylation in hypothyroid and atherosclerotic conditions in animal and cellular models.

Conclusions:

• Accelerated atherosclerosis in hypothyroid patients may result from the suppression of the TAK1-AMPK pathway within macrophages.
• The TAK1-AMPK pathway represents a potential novel therapeutic target for managing atherosclerosis in hypothyroid individuals.
• Further research into the TAK1-AMPK pathway could lead to improved strategies for preventing and treating cardiovascular disease in this patient population.