| Abstract: | The heterogeneity of serum low-density lipoproteins (LDL) was studied in patients with cholelithiasis (CL) and gallbladder cholesterolosis (GBC). Native gradient (3-12%) polyacrylamide gel electrophoresis was used, followed by densitometric scanning and analysis; a correlation analysis of the levels of cholesterol levels, the body-mass index (BMI), and age was made. Various heterogeneity of LDL was revealed in CL and GBC. In the group of patients with GBC, the subfraction spectrum of LDL was characterized by a predominance of minor dense particles of LDL (Rf = 0.171 +/- 0.003), which significantly differed from that in the patients with CL (Rf = 0.146 +/- 0.004) and the controls (Rf = 0.144 +/- 0.013, p < 0.05). The increased levels of total cholesterol were associated with the changes in the subfraction spectrum of LDL with a moderate correlation (r = 0.596 and r = 0.343, respectively). However, a correlation was found between the variability of LDL, BMI, and age (r = 0.533 and r = 0.363, respectively) whereas in GBC it was absent (r = 0.148 and r = 0.117). The findings suggest that the minor dense subfractions of LDL are a risk factor for GBC irrespective of age and body mass. The modified minor particles of LDL more rapidly penetrate than other LDL fractions into the gallbladder tissue, where the gallbladder wall is intensively captured by macrophages, and participate in the formation of foamy cells. In CL, the increase in total cholesterol levels is not followed by so marked changes in the structure of LDL. The much lower proportion of minor dense particles that are components of LDL is a cause of the low entry of apolipoproteins into the gallbladder wall in CL as compared with GBC. |
