Structural and Nonlinear Optical Characteristics of In Vitro Glycation of Human Low-Density Lipoprotein, as a Function of Time
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Modified low-density lipoprotein (LDL) is a well-known risk marker for diabetes and cardiovascular disease. In vitro and in vivo studies have shown that native LDL particles, when modified by oxidation and/or glycation processes, become proatherogenic. Other studies have shown that high LDL concentrations also contribute to atherogenic diseases. In the present in vitro study, we investigate structural characteristics, linear and nonlinear optical properties of LDL particles modified by glycation, compared to modified-control and non-modified LDL (LDLnat). LDL particles were isolated from normolipidemic individuals and aliquots were incubated in PBS (LDLcontrol) and glycated (LDLglyc) with glycolaldehyde (GAD) from 2 to 6 days. The nonlinear optical Z-Scan experiments indicate that GAD modifies the optical properties of the LDL. These results indicate the application of a nonlinear optical technique as a tool to investigate the characteristics of LDL particles, in particular when modifications are induced in the particles by glycation.
KeywordsLDL Structure Glycation Z-scan technique
From Brazil, we acknowledge the National Council for Scientific and Technological Development (CNPq – 465259/2014-6), the Coordination for the Improvement of Higher Education Personnel (CAPES), the National Institute of Science and Technology Complex Fluids (INCT-FCx), and the São Paulo Research Foundation (FAPESP – 2014/50983-3 and 2016/24531-3).
A.P.Q.M. wrote the manuscript and made the LDL glycation; G.A. made the Z-Scan experiment; D.H.G.E. did the linear optical experiment and analyzed the Z-Scan data; D.R. did the X-ray experiment and analysis; A.M.F.N. designed the experiment, wrote and revised the manuscript, and researched data. The guarantor is Prof. Dr. Antonio Martins Figueiredo Neto.
Compliance with Ethical Standards
The project was approved by the ethics committee of the university and all participants provided written informed consent prior to study initiation.
Conflict of interest
The authors declare that they have no conflict of interest.
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