Aging and Western diet consumption jointly impair thyroid hormone metabolism in the liver through altered deiodinase enzyme activity, depleting active thyroid hormone at the cellular level and accelerating fatty liver disease progression. Restoring thyroid hormone signaling reverses senescence markers and reduces inflammation, identifying a therapeutic pathway for metabolic liver disease in aging populations.
Key Points
- Aging decreases Dio1 activity, blocking T4-to-T3 conversion in hepatocytes.
- Western diet and aging synergistically reduce intrahepatic thyroid hormone levels.
- Thyroid hormone agonist reverses cellular senescence and inflammatory markers.
Longevity Analysis
The liver's capacity to activate thyroid hormone declines with age, and dietary patterns amplify this deficit through enzyme dysregulation. This reveals a mechanistic link between aging, nutritional stress, and metabolic disease that operates at the level of hormone signaling within individual cells. The finding redirects therapeutic attention from symptom management to restoring the body's ability to generate active thyroid hormone locally—a function critical to energy metabolism, inflammation regulation, and cellular regeneration. For practitioners evaluating metabolic health in aging patients, this suggests the value of assessing hepatic thyroid hormone metabolism as a distinct target, separate from systemic thyroid function assessments, particularly in those consuming a high-fructose diet.
Original published by Wiley Aging Cell, by Xinru Zhang, Madhulika Tripathi, Chun Ting Goh, Chee Seng Chan, Anita Boelen, Paul M. Yen, Brijesh Kumar Singh, Eveline Bruinstroop .