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Emcitate (tiratricol)

MCT8 deficiency

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78 sources

Product information and disease descriptionPlace of product in therapyDisease description

Pathophysiology

3 evidence topics · 3 sources

Central hypothyroidism and chronic peripheral thyrotoxicosis

“Disordered thyroid hormone transport, due to mutations in the SLC16A2 gene encoding monocarboxylate transporter 8 (MCT8), is characterised by intellectual and motor disability resulting from cerebral hypothyroidism and chronic peripheral thyrotoxicosis.” (opens the source at this quote in a new tab)

Tissue-specific thyroid hormone transport and elevated serum T3

“Tri-iodothyronine (T3) transport across the blood-brain barrier is highly MCT8-dependent; therefore, individuals with MCT8 deficiency exhibit markedly low levels of T3 in the central nervous system. In contrast, T3 can enter peripheral tissues outside the central nervous system through alternative transporters, albeit with lower specificity.” (opens the source at this quote in a new tab)

“However, peripheral thyrotoxicosis in MCT8 deficiency is directly related to consistently elevated serum T3 levels, while thyroid-stimulating hormone (TSH) and free (F)T4 may be normal or only mildly altered” (opens the source at this quote in a new tab)

“It should be noted that the exact mechanisms underlying the distinctive TH profile in MCT8 deficiency have not yet been conclusively defined, and further research is needed to clarify the precise drivers of T3 elevation in these patients.” (opens the source at this quote in a new tab)

Peripheral manifestations and serum markers of thyroid hormone excess

“At the peripheral level, T3 may enter the tissues by alternative transporters and cause peripheral hyperthyroidism, manifested by warm skin, tachycardia, arterial hypertension (HTN), and poor height and weight growth. The synthesis of sex hormone binding globulin (SHBG) increases and cholesterol and creatinine levels decrease; muscle hypoplasia and low creatinine kinase (CPK) levels also occur.” (opens the source at this quote in a new tab)