Standard values of rapid turnover proteins and zinc in Japanese children

Area of Science:

• Pediatric Nutrition
• Biochemical Markers
• Clinical Chemistry

Background:

• Rapid-turnover proteins are crucial for nutrition assessment, influenced by zinc metallo-enzymes.
• Establishing age-specific reference values for these proteins in children is essential for accurate nutritional status evaluation.
• Zinc's role in protein metabolism highlights the need to consider zinc status alongside protein measurements.

Purpose of the Study:

• To determine reference values for rapid turnover proteins (transthyretin and retinol-binding protein) in healthy Japanese children.
• To investigate the relationship between these protein levels, zinc status, and anthropometric parameters in pediatric populations.
• To provide updated nutritional assessment standards for Japanese children.

Main Methods:

• Cross-sectional study involving Japanese children aged 0-12 years with specific health conditions (hernias) and normal BMI z-scores (-2 to 2).
• Measurement of transthyretin and retinol-binding protein levels.
• Analysis of correlations between protein levels, age, and anthropometric measurements.

Main Results:

• Established standard reference ranges for transthyretin and retinol-binding protein across infant, preschool, and preadolescent age groups.
• Found no significant differences in rapid turnover protein levels among the studied age groups.
• Transthyretin showed weak positive correlations with age and lean body mass; retinol-binding protein did not correlate with these parameters.

Conclusions:

• Provided essential reference values for transthyretin and retinol-binding protein in Japanese children, considering zinc status.
• Demonstrated that these rapid turnover proteins have limited correlation with anthropometric parameters for assessing protein-energy malnutrition in this cohort.
• These findings support the use of established reference values for nutritional assessment in pediatric populations.