Age-related decrease of urinary excretion of human epidermal growth factor (hEGF)

Area of Science:

• Biochemistry
• Endocrinology
• Gerontology

Background:

• Epidermal Growth Factor (EGF) is a potent mitogen with largely undetermined physiological roles in humans.
• EGF has been isolated from mouse submandibular glands and human urine.
• Understanding human EGF (hEGF) physiology is crucial for various health aspects.

Purpose of the Study:

• To investigate the effect of aging on urinary hEGF excretion in normal subjects.
• To determine if age influences the levels of hEGF found in urine.
• To compare hEGF excretion between different age groups and sexes.

Main Methods:

• A homologous radioimmunoassay (RIA) was employed to quantify hEGF.
• Urinary hEGF levels were measured in a cohort of normal subjects aged 20-79 years.
• hEGF excretion was normalized to creatinine levels to account for urinary concentration variations.

Main Results:

• Urinary hEGF excretion, when normalized to creatinine, showed a significant decline with increasing age.
• Females exhibited significantly higher urinary hEGF excretion compared to males across the studied age range.
• A clear inverse correlation between age and hEGF levels was observed.

Conclusions:

• Urinary hEGF excretion decreases in normal individuals as they age.
• The observed decrease may be attributed to reduced synthesis and/or secretion of hEGF.
• Sex-based differences in hEGF excretion warrant further investigation regarding age-related changes.