Perinatal nitrogen accretion in muscles and fingernails

Area of Science:

• Biochemistry
• Neonatalogy
• Nutritional Science

Background:

• Intrauterine growth retardation (IGR) impacts neonatal health and development.
• Accurate assessment of protein status is crucial for monitoring perinatal growth.
• Noninvasive biomarkers are needed for evaluating nutritional status in neonates.

Purpose of the Study:

• To investigate the relationship between muscle nitrogen and fingernail nitrogen content in neonates.
• To explore the potential of using fingernail nitrogen as a noninvasive marker for protein economy.
• To assess protein quality and growth in normally grown (NG) and IGR neonates.

Main Methods:

• Autopsy samples of triceps muscle and fingernails were collected from 41 neonates (25 NG, 16 IGR).
• Muscle samples were processed (desiccated, defatted, ground).
• Nitrogen content in muscle and fingernails was quantified using a modified micro-Kjeldahl technique.

Main Results:

• Muscle nitrogen content was similar between NG and IGR neonates, and across gestational ages.
• Fingernail nitrogen content showed no significant variation related to intrauterine growth.
• A significant positive linear correlation was found between fingernail and muscle nitrogen content in both groups (r=0.59, P<0.001).

Conclusions:

• Fingernail nitrogen content serves as a reliable indicator of muscle nitrogen content in neonates.
• Noninvasive fingernail analysis offers a promising method for monitoring protein economy during perinatal development.
• This approach could aid in assessing the quality of growth in both normally grown and growth-restricted infants.