Lipoprotein lipase gene polymorphism and lipid profile in patients with hypertriglyceridemia.

AIM: To assess lipid profile and the genotype distribution of lipoprotein lipase gene polymorphism at Pvu II polymorphic site within the intron between exons 6 and 7 in patients with hypertriglyceridemia. METHODS: Pvu II polymorphism was determined in 116 hypertriglyceridemic patients and 50 normolipidemic controls from Zagreb, Croatia. DNA was extracted from peripheral blood mononuclear cells. Polymerase chain reaction was used for amplification of 6th intron, which was then restricted with Pvu II-restriction endonuclease. Serum lipid and lipoprotein fractions were determined by standard enzymatic methods. Cholesterol concentrations in HDL subfractions, HDL2 and HDL3, were determined after precipitation with polyethyleneglycol. Apolipoproteins (apo) A-I and B were determined by immunonephelometry. RESULTS: Triglycerides showed a positive correlation with total cholesterol (r=0.222, 95% CI=0.041-0.389, p=0.017) and inverse correlation with HDL-cholesterol (r= -0.278, 95% CI= -0.449 to -0.088, p=0.005), especially with HDL3-cholesterol (r= -0.333, 95% CI= -0.497 to -0.147, p=0.001). The respective frequencies for genotypes /, +/, and +/+ were 22, 58, and 36 in the patient group, and 17, 17, and 16 in the control group. Serum triglycerides in the patient group, expressed as median in mmol/L, were 3.30 (range, 2.60-10.90), 3.60 (range, 2.50-21.50), and 3.99 (range, 2.50-15.56), respectively. Serum concentration of triglycerides differed significantly between the +/+ and / genotype (p=0.043). CONCLUSION: There is an association between genetic variation at the locus for lipoprotein lipase and high serum triglyceride levels. This might prove useful in the detection of individuals susceptible to the development of hypertriglyceridemia, as well as a marker in the analysis of this genetic defect in patient families.

Multiple forms of gamma-glutamyltransferase and lipoproteins.

The gamma-glutamyltransferase isoenzyme patterns originating from human serum and homogenates of liver, kidney, pancreas and intestine in the presence and in absence of isolated lipoproteins has been studied. On the basis of these results one can conclude that the distribution of a variety of gamma-glutamyltransferase activities obtained by the electrophoresis of blood serum is not a consequence of an existence of a large number of true isoenzymes, but of increased concentrations of lipoproteins which bind to the enzyme thus causing the appearance of gamma-glutamyltransferase in the region of the appropriate lipoproteins.

Effect of sodium tetrathionate on the activities of some enzymes in kidney and urine.

The activities of lactate dehydrogenase, glutamate dehydrogenase, aspartate aminotransferase, beta-galactosidase, N-acetyl-beta-D-glucosaminidase, leucine aminopeptidase, gamma-glutamyltransferase and alkaline phosphatase in renal tissue and urine of rats treated with sodium tetrathionate were determined. A decrease of enzyme activities in renal tissue and an increase in urine were observed. The largest decrease in the glutamate dehydrogenase of renal tissue amounted to 0.7 times the control value, and was correlated with an appropriate increase in the urine. Increases in urinary enzyme activity were especially marked for beta-galactosidase and N-acetyl-beta-D-glucosaminidase (3 and 6 times the control values, respectively). The increase in enzyme activities was not accompanied by a corresponding change in the urinary protein. Characterization of urinary lactate dehydrogenase and N-acetyl-beta-D-glucosaminidase isoenzymes also indicates the renal origin of these enzymes. The abnormally high enzyme activities of the urine correlated with the nature and degree of renal damage shown by electron microscopy.