Binding of CML-Modified as Well as Heat-Glycated β-lactoglobulin to Receptors for AGEs is Determined by Charge and Hydrophobicity

International Journal of Molecular Sciences

Arifa Ewaz¹  HuubF. J. Savelkoul¹  Malgorzata Teodorowicz¹  R.J. Joost van Neerven¹  HannahE. Zenker²  KasperA. Hettinga²  NicoletteW. De Jong³  HarryJ. Wichers⁴ 

[1] Cell Biology & Immunology, Wageningen University & Research Centre, 6700 AH Wageningen, The Netherlands;Food Quality & Design Group, Wageningen University & Research Centre, 6708 WG Wageningen, The Netherlands;Internal Medicine, dept. Allergology & Clinical Immunology and Erasmus University Medical Centre Rotterdam, 3000CA Rotterdam, The Netherlands;Wageningen Food & Biobased Research, Wageningen University & Research Centre, 6708 WG Wageningen, The Netherlands;

关键词: CD36;    charge;    Galectin-3;    glycation;    sRAGE;    Nε-carboxymethyl lysine;   

DOI  :  10.3390/ijms21124567

来源: DOAJ

【 摘 要 】

Intake of dietary advanced glycation end products (AGEs) is associated with inflammation-related health problems. Nε-carboxymethyl lysine (CML) is one of the best characterised AGEs in processed food. AGEs have been described as ligands for receptors present on antigen presenting cells. However, changes in protein secondary and tertiary structure also induce binding to AGE receptors. We aimed to discriminate the role of different protein modifications in binding to AGE receptors. Therefore, β-lactoglobulin was chemically modified with glyoxylic acid to produce CML and compared to β-lactoglobulin glycated with lactose. Secondary structure was monitored with circular dichroism, while hydrophobicity and formation of β-sheet structures was measured with ANS-assay and ThT-assay, respectively. Aggregation was monitored using native-PAGE. Binding to sRAGE, CD36, and galectin-3 was measured using inhibition ELISA. Even though no changes in secondary structure were observed in all tested samples, binding to AGE receptors increased with CML concentration of CML-modified β-lactoglobulin. The negative charge of CML was a crucial determinant for the binding of protein bound CML, while binding of glycated BLG was determined by increasing hydrophobicity. This shows that sRAGE, galectin-3, and CD36 bind to protein bound CML and points out the role of negatively charged AGEs in binding to AGE receptors.

【 授权许可】

Unknown