Structural analysis of glycated human hemoglobin using native mass spectrometry

Area of Science:

• Biochemistry
• Analytical Chemistry
• Clinical Diagnostics

Background:

• Glycated hemoglobin (GHb) reflects long-term glycemic control.
• Standard methods like cation exchange chromatography separate GHb from native hemoglobin (HbA0).
• Multiple glycation sites can complicate GHb assessment.

Purpose of the Study:

• To structurally characterize in vivo glycated hemoglobin (GHb).
• To investigate the glycation pattern across alpha and beta globin chains.
• To validate mass spectrometry for accurate GHb quantification, particularly in individuals with mutant HbA.

Main Methods:

• Native mass spectrometry was employed to determine the stoichiometric composition of glycated hemoglobin.
• Analysis of glycation patterns in mono-, di-, and tri-glycated HbA0 samples.
• Correlation of mass spectrometry-based GHb quantification with conventional methods.

Main Results:

• Hemoglobin glycation occurs symmetrically across alpha and beta globin chains, preferring unmodified globin first.
• Mass spectrometry provides a reliable estimation of the glycemic index for individuals with HbA0.
• The proposed method is suitable for assessing glycemic index in individuals with mutant HbA variants.

Conclusions:

• Hemoglobin glycation follows a symmetrical pattern, enhancing the reliability of glycemic index assessment.
• Native mass spectrometry offers a robust alternative for GHb quantification, especially for diverse hemoglobin types.
• This approach improves diagnostic accuracy for long-term glucose monitoring.