**2. Material and methods**

Experiments were planned to develop a diet-induced MS in Golden Syrian hamsters of different sex and age (4 weeks, 20 weeks, 1 year at the beginning of the experiment), which were kept in a standard vivarium condition. Animals were fed a standard normal diet (intact group), and for 5 weeks a high-calorie diet that contained 29% of fats (predominantly saturat‐ ed) with fructose addition – 1 g daily per 100 g body weight (MS groups) [27, 63]. Blood and liver samples were taken after decapitation in necessary terms and prepared according to individual procedures.

Experiments were carried out according to the "European Convention for the Protection of Vertebrate Animals used for Experimental and other Scientific Purposes" (Strasbourg, 1985).

Lipoprotein fractions (very low density lipoproteins (VLDL); low density lipoproteins (LDL), and high density lipoproteins (HDL)) were determined using electroforesis. Total LDL and apoB-containing lipoproteins (apoB-LP) in blood serum and hepatic cytosol were determined by gradient gel electrophoresis [1]. Using these data (apoВ-LP concentration and data of LP fractions percentage), we calculated the content of every LP fraction. Total lipids (TL) were fractionated by thin layer chromatography on the plates with silica layers Silufol U.V.254'' (Sklarny Kavalier, Czech Republic).

Triacylglycerol (TAG) content was determined by enzymatic assay ("KONE," Finland).

Free and esterified cholesterol (CE) was determined by enzymatic assays ("Boehringer Mannheim GmbH diagnostica," Germany). Total lipid concentration was determined by standard test using vanillin reagent (Eagle Diagnostics, USA).

Cholesterol esterification rate and cholesterol ester (CE) transfer was estimated in the HDL fraction received by centrifugation and then incubation of material and measuring of choles‐ terol and CE before and after incubation (for determination of cholesterol esterification rate – adding 5,5′-dithiobis(2-nitrobenzoic acid) [82].

Lipoprotein lipase (LPL, EC 3.1.1.34) activity and hepatic triglyceride lipase (HL, EC 3.1.1.3) were determined by the method of Lithell and Boberg [52].

Glucose-6-phosphate dehydrogenase (G6PDH, EC 1.1.1.49) activity was measured using assay kit (Cayman Chemical, USA), 6-phosphogluconate dehydrogenase (6PGD, EC 1.1.1.44) using assay kit (Biocompare, USA), and malate dehydrogenase (EC 1.1.1.40) using assay kit (Biovi‐ sion, USA).

Lysosomal acid lipase (LAL, EC 3.1.1.3) activity was measured in hepatic mitochondrial/ lysosomal fraction by the substrate hydrolysis – 4-methylumbelliferone determined fluoro‐ metrically (Е=449 nm, 410 nm) [86]. Protein content was determined by Lowry in Miller modification.

Statistical analysis was performed using nonparametric van der Waerden criterion [21, 87] with packet Excel and Statistica, and the correlation coefficient was calculated by Spearman.
