In neurons, the type 3 deiodinase (D3) inactivates thyroid hormone and reduces oxygen consumption, thus creating a state of cell-specific hypothyroidism. Here we show that hypoxia leads to nuclear import of D3 in neurons, without which thyroid hormone signaling and metabolism cannot be reduced. After unilateral hypoxia in the rat brain, D3 protein level is increased predominantly in the nucleus...

BACKGROUND Similar to other systems, the endocrine system is affected by aging. Thyroid hormone, the action of which is affected by many factors, has been shown to be associated with longevity. The most useful marker for the assessment of thyroid hormone action is TSH level. Although age and gender are believed to modify the pituitary set point or response to free thyroid hormone concentration,...

Thyroid hormone has been studied in cardiovascular disease but rarely in cerebrovascular disease (CVD). Recently, hypothyroidism has been suggested to be related to risk factors such as atherosclerosis but not directly to CVD. We reported a 52-year-old woman with acute ischemic stroke, and greatly improved general conditions after thyroid hormone replacement. Hypothyroidism is reported to be on...

Unrecognized congenital hypothyroidism leads to mental retardation. Newborn screening and thyroid therapy started within 2 weeks of age can normalize cognitive development. The primary thyroid-stimulating hormone screening has become standard in many parts of the world. However, newborn thyroid screening is not yet universal in some countries. Initial dosage of 10 to 15 microg/kg levothyroxine ...

Background: Although there is little information about the prevalence of thyroid disorders in young women, but they are common Iraq. Objective: To hormones test abnormality females at reproductive age attending al-batool maternity teaching hospital Patients and Methods: This study involved 1570 female ages patients Al-batool Maternity Hospital Diyala Province, Serum levels T3, T4, TSH were meas...

The genomic actions of thyroid hormone and steroids depend upon primary interactions of the hormones with their specific nuclear receptor proteins. Formation of nuclear co-activator or co-repressor complexes involving the liganded receptors subsequently result in transcriptional events-either activation or suppression-at genes that are specific targets of thyroid hormone or steroids. Nongenomic...

BACKGROUND Hydroxylated polybrominated diphenyl ethers (HO-PBDEs) may disrupt thyroid hormone status because of their structural similarity to thyroid hormone. However, the molecular mechanisms of interactions with thyroid hormone receptors (TRs) are not fully understood. OBJECTIVES We investigated the interactions between HO-PBDEs and TRbeta to identify critical structural features and physi...

In the treatment of primary hypothyroidism, guidelines issued by some organizations advise merely normalizing the TSH, reducing it to any value within the reference range. However, many studies show that this approach often produces little improvement in symptoms or in the risk of diseases associated with hypothyroidism. For this reason, some organizations and experts recommend titrating T4 dos...

The heart is an organ sensitive to the action of thyroid hormone, and measurable changes in cardiac performance are detected with small variations in thyroid hormone serum concentrations. Most patients with hyperthyroidism experience cardiovascular manifestations, and the most serious complications of hyperthyroidism occur as a result of cardiac involvement. Recent studies provide important ins...

Synthetic thyroxine has replaced animal thyroid gland extract as the preferred drug in chronic thyroid hormone replacement. Synthetic thyroxine monotherapy is used to treat overt primary and secondary hypothyroidism, and some cases of subclinical hypothyroidism. In addition, thyroid-stimulating hormone suppressive therapy with thyroxine is a component of the chronic treatment for differentiated...