Serum and plasma epidermal growth factor in thyroid disorders

Area of Science:

• Endocrinology
• Molecular Biology

Background:

• Epidermal growth factor (EGF) is a key mitogen.
• Thyroid hormone levels influence EGF secretion in neonates.
• EGF is present in human serum (platelet-associated) and plasma, with plasma origin unclear.

Purpose of the Study:

• To investigate the relationship between thyroid disorders and serum/plasma EGF levels in humans.
• To determine if EGF levels change with altered thyroid states (hyperthyroidism, hypothyroidism).

Main Methods:

• Serum and plasma EGF levels were measured in hyperthyroid and hypothyroid patients before and after treatment.
• Comparison with normal control subjects.
• Correlation and regression analyses were performed with serum-free thyroxine index (FTI) and platelet count.

Main Results:

• Serum EGF was significantly elevated in untreated hyperthyroid patients compared to controls.
• Serum EGF normalized after hyperthyroid treatment.
• Hypothyroid patients showed no significant difference in serum EGF levels.
• Plasma EGF was elevated in hyperthyroid patients, undetectable in controls and hypothyroid subjects.
• Serum EGF correlated significantly with serum-free thyroxine index (FTI).
• Both serum FTI and platelet count independently affected serum EGF levels.

Conclusions:

• Thyroid status, particularly hyperthyroidism, significantly influences serum and plasma EGF levels.
• EGF levels normalize with restoration of euthyroidism.
• Serum EGF is influenced by both thyroid hormone status and platelet count.