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Objectives. To determine the effect of end-stage renal failure on the biochemical composition of blood lipoprotein complexes. Material and methods. The work is carried out within the frames of the State Research Program «Translational Medicine, 2020 - 2025», subprogram 4.2 «Fundamental Aspects of Medical Science» on task 3.37, State Registration Number 20220305. The study group of patients was composed of 15 men (36-60 years old) and 16 women (36-55 years old) with the end-stage chronic kidney disease, the control group consisted of 15 healthy men and women of the same age. Lipoprotein complexes (LPC) were isolated by sequential ultracentrifugation on the preparative ultracentrifuge, the amount of protein in native LPC was determined by the Lowry method, cholesterol and triacylglycerides – by a biochemical method, proprotein convertase subtilisin kexin 9 (PCSK9) – by enzyme immunoassay in blood serum. Results. There are no gender differences characteristic of healthy subjects in the individuals of the study group. In patients with chronic renal failure (CRF), the level of VLDL TG is higher than that in the control group, and cholesterol and VLDL protein are increased compared to healthy women. The amount of LDL TG in the study group is higher compared to the control group, and the amount of LDL protein is increased in comparison with women in the control group. Conclusion. CRF possesses a proatherogenic effect and eliminates gender differences characteristic of healthy individuals, and it also has a stronger effect on women, increasing the content of total VLDL cholesterol and VLDL and LDL protein. CRF does not affect the amount of PCSK9.

• Electrodialysis treatment time increases with protein concentration factor. • Demineralization is not sufficient to lower ionic strength alone. • A dilution after electrodialysis treatment increases defatting rate. • Proteins can also precipitate in protein complexes. Every year, sweet whey is generated in huge quantities and its valorization is often accompanied by a preliminary skimming step by centrifugation. However, some residual lipids may still be present after skimming process and cause technological issues. Electrodialysis with bipolar membrane (EDBM) can be used to remove these residual lipids as it simultaneously decreases pH and ionic strength allowing the formation of lipoprotein complexes than can further be recovered. The aim of this work was to treat whey protein concentrates (WPCs) with different protein concentration factor (2.27X, 3.34X, 3.56X and 3.80X) by EDBM and to evaluate the impact of the protein concentration factor on the process efficiency, particularly on the defatting rate (when a dilution was applied or not). It appeared that, whatever the protein concentration factor, a dilution was needed to reach higher defatting rates (ex.: 8.37 ± 1.72% without dilution vs 78.02 ± 0.66% with a 6X dilution for WPC 3.80X), as EDBM was not sufficient alone to lower ionic strength to promote lipoprotein complex formation. Furthermore, when a dilution was applied after EDBM treatment, a higher protein concentration factor slightly increased the defatting rate (ex.: 72.76 ± 0.71% for WPC 2.27X vs 78.02 ± 0.66% for WPC 3.80X) as a further lower ionic strength and a higher protein content favorized the lipoprotein complex formation. The increase in the defatting rate was however not proportional to the protein concentration factor. Furthermore, these conditions also allowed proteins to form protein complexes that precipitated along with the lipoprotein complexes. To our best knowledge, it was the first time that protein concentration factor of sweet whey was studied regarding the defatting rate after treatment by EDBM. [ABSTRACT FROM AUTHOR]