The Role of the Liver in High Density Lipoprotein Metabolism

We measured the levels of HDL2 and HDL3 cholesterol in patients with liver cirrhosis or chronic hepatitis, and in normal control subjects by high performance liquid chromatography to clarify the metabolic mechanism of HDL subfractions. Twenty three patients with liver cirrhosis and thirteen patients with chronic hepatitis, and twenty two normal control subjects were studied. The diagnosis in the patients with liver cirrhosis or chronic hepatitis was based on liver biopsy, laparoscopy, and laboratory tests.The values of HDL, HDL2, and HDL3 cholesterol were compared between male patients with liver deseases (liver cirrhosis and chronic hepatitis) and normal male controls. The values of obesity index and triglyceride were matched between the patients with liver cirrhosis and the normal controls. There was no significant difference in HDL cholesterol levels between the patients with liver cirrhosis and the normal controls. However in liver cirrhosis there was a decrease in HDL3 cholesterol and a increase in HDL2 cholesterol as compared with normal subjects (p<0.001, Fig. 1).Table 1 and Table 2 show the correlation of HDL subfractions with liver function tests in thirty-six patients with liver diseases (liver cirrhosis and chronic hepatitis). We found a positive correlation of HDL3-cholesterol with serum albumin and choline esterase values, and a negative correlation of HDL3 cholesterol with ICG test, serum alkaline phosphatase, and serum total bilirubin values. Furthermore we found a positive correlation of HDL2 cholesterol with ICG test, serum alkaline phosphatase, and serum total bilirubin values, and a negative correlation of HDL2 cholesterol with serum albumin and choline esterase values.The decrease of HDL3 cholesterol in liver cirrhosis and the positive correlation of HDL3 cholesterol with other indicators of hepatic protein synthesis (albumin and choline esterase) suggest that HDL3 are secreted from the liver. The increase of HDL2 cholesterol in liver cirrhosis and the positive correlation with ICG test, serum alkaline phosphatase, and total bilirubin values indicate the possibility that HDL2 may be taken up and degraded in the liver.