Background: Cholesterol homeostasis disorders may cause dyslipidemia, atherosclerosis progression and coronary artery disease (CAD) development. Evaluation of non-cholesterol sterols (NCSs) as synthesis and absorption markers, and lipoprotein particles quality may indicate the dyslipidemia early development. This study investigates associations of different cholesterol homeostasis patterns with low-density (LDL) and high-density lipoproteins (HDL) subclasses distribution in statin-treated and statin-untreated CAD patients, and potential use of aforementioned markers for CAD treatment optimization.Methods: The study included 78 CAD patients (47 statin-untreated and 31 statin-treated) and 31 controls (CG). NCSs concentrations were quantified using gas chromatography- flame ionization detection (GC-FID). Lipoprotein subclasses were separated by gradient gel electrophoresis.Results: In patients, cholesterol-synthesis markers were significantly higher comparing to CG. Cholesterol-synthesis markers were inversely associated with LDL size in all groups. For cholesterol homeostasis estimation, each group was divided to good and/or poor synthetizers and/or absorbers according to desmosterol and β-sitosterol median values. In CG, participants with reduced cholesterol absorption, the relative proportion of small, dense LDL was higher in those with increased cholesterol synthesis compared to those with reduced synthesis (p<0.01). LDL I fraction was significantly higher in poor synthetizers/poor absorbers subgroup compared to poor synthetizers/good absorbers (p<0.01), and good synthetizers/poor absorbers (p<0.01). Statin-treated patients with increased cholesterol absorption had increased proportion of LDL IVB (p<0.05).Conclusions: The results suggest the existence of different lipoprotein abnormalities according to various patterns of cholesterol homeostasis. Desmosterol/β-sitosterol ratio could be used for estimating individual propensity toward dyslipidemia development and direct the future treatment.

Milk and dairy products exhibit a beneficial nutritional and health effects and represent 20% to 30% of global food consumption. Whey proteins have great anabolic and cardioprotective role. Increased concentration of cholesterol contained in high density lipoproteins (HDL), paraoxonase 1 (PON1) higher activity, and diminished relative proportion of small dense low density lipoproteins (sdLDL) reduce cardiovascular diseases (CVD) risk. Current longitudinal study enrolled 10 healthy volunteers. All participants consumed lyophilized goat whey (LGW) (Koza Nostra®) for two months (3 g per day). Concentrations of basic biochemical parameters were measured by routine methods. Concentration of oxidative stress status parameters were measured spectrophotometrically. Serum PON1 activity was measured kinetically using paraoxon as a substrate. Lipoproteins subfractions were separated by gradient-gel electrophoresis. A significant decrease in urea concentrations (p<0.05) and trend toward higher albumin concentrations were observed after LGW supplementation. A significant increase in values of prooxidative-antioxidative balance (p<0.05) and PON1 activity (p<0.05), as well as a trend toward lower malondialdehyde concentrations were observed after supplementation. Trends toward higher relative proportion of HDL 3c subclasses and an increase in LDL lipoprotein particle diameter were observed. The findings of the present study have shown that increased protein synthesis, PON1 enzyme activity and shift toward increased HDL 3c relative proportions could indicate that LGW has a positive effect on synthetic liver function and CVD risk reduction. Our findings suggest that LGW may protect against free radicals by stimulating the antioxidant defense mechanisms and promoting a mild prooxidative effect.