Disorder of thyroid hormones may cause cardiovascular diseases


Disorder of thyroid hormones may cause cardiovascular diseases

Hormones occupy a special place in accomplishment of several functions of the body. Accordingly, thyroid hormones play a key role in the management of human metabolism. Acceleration of the basal metabolic rate as well as the energy metabolism of tissues in numerous mammalian species is considered as one of the main functions of thyroid hormones1.

Hypothyroidism is characterized by under activity of the thyroid gland; it is basically an ailment in which the thyroid gland produces less than the usual quantity of thyroid hormones (T3 and T4). Whereas, reduced thyroid function is generally linked with fatigue,weight gain, depression and cold intolerance. Moreover, sub-optimal thyroid function has also been connected with amplified frequency of heart failure, coronary heart disease2.

Free radicals are regarded ashighly reactive molecules that can lead towards lipid peroxidation andcan damage the macro molecules, endothelium and erythrocytes as well as cellular structure of the organism. Oxygen free radicals possess significant effects on the pathogenesis of tissue damage of numerous pathologic conditions3. According to earlier clinical and experimental investigations, in hypothyroidism level of free radical gets altered.

These facts urged scientists for conducting a new research in order to evaluate the possibility of modification in lipid peroxidation due to hypothyroidism. For this purpose, scientists selected 28 subjects having hypothyroidism as well as thirty three subjects with euthyroid. Afterwards, scientists collected the blood samples and then measured serum malondialdehyde, T3, T4 as well as TSH4.

In conclusion, the results show that hypothyroidism may not modulate the free-radical-induced oxidative damage and that hypothyroidism may not present some protection against lipid peroxidation.

During this study, it was concluded that the enhanced lipid peroxidation can play a role in the free-radical-induced oxidative damage of some tissues in hypothyroidism. This phenomenon points towards a significant relation between hypothyroidism as well as lipid peroxidation. Conclusively; hypothyroidism is linked with amplified susceptibility to lipid peroxidation compared to that in the euthyroid state.


  1. Schawrtz, H.L. and J.H. Oppenheimer, 1978. Physiologic and biochemical actions of thyroid hormone. Pharmacol. Therapeutics, 33: 349-376.
  2. Schmidt-Oft, U.M. and D.D. Ascheim, 2006. Thyroid hormone and heart failure. Heart Foil Rep., 3: 114-119.
  3. Halliwell, B., 1994. Free radicals, antioxidants and human disease: Curiosity, cause, or consequence? Lancet, 344: 721-724.
  4. AbdoljalalMarjani, Azad Reza Mansourian, EzzetOllahGhaemi, AlirezaAhmadi and VahidKhori, 2008. Lipid Peroxidation in the Serum of Hypothyroid Patients (In Gorgan-South East of Caspian Sea) . Asian J. Cell Biol., 3: 47-50.