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Thyroid hormone metabolism in heart failure: iodothyronine deiodinases in focus

Emerson L Olivares1, Denise P Carvalho

  • 1Departamento de Ciências Fisiológicas, Instituto de Biologia, Universidade Federal Rural do Rio de Janeiro, Rio de Janeiro, Brazil.

Current Opinion in Endocrinology, Diabetes, and Obesity
|July 21, 2010
PubMed

Insights

Heart failure alters thyroid hormone levels, decreasing T3 and increasing rT3. Understanding this "low T3-syndrome" and its regulation is key to developing new heart failure treatments.

Area of Science:

  • Cardiology
  • Endocrinology
  • Metabolic Regulation

Background:

  • Heart disease is a leading global cause of mortality with limited effective treatments.
  • Thyroid hormones, known for their cardiovascular effects, are being explored as a therapeutic avenue for heart disease.
  • While thyroid hormone replacement shows promise in heart failure, its precise role and metabolic changes remain unclear.

Purpose of the Study:

  • To review alterations in thyroid hormone economy.
  • To specifically examine thyroid hormone metabolism in heart failure models.
  • To elucidate the pathophysiology of thyroid hormone dysregulation in heart failure.

Main Methods:

  • Review of existing clinical and experimental studies.
  • Analysis of thyroid hormone levels (T3, rT3) in heart failure.
  • Investigation of the role of deiodinase enzymes, particularly type 3 deiodinase (D3).

Main Results:

  • Heart failure is associated with the 'low T3-syndrome' (decreased T3, increased rT3).
  • Some models show compensatory stimulation of the hypothalamus-pituitary-thyroid axis.
  • Increased activity of type 3 deiodinase is a primary driver of decreased T3, resembling 'consumptive hypothyroidism'.

Conclusions:

  • Cardiac thyroid hormone T3 levels are tightly regulated in heart failure.
  • Understanding the underlying pathophysiology can guide the development of novel heart failure therapies.
  • Further research into thyroid hormone metabolism is crucial for effective heart failure treatment strategies.
Abstract

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