Acid and neutral lipase activity in lymphocytes of patients with increased serum cholesterol and triglyceride level.

Acid lipase activity (ALA) and neutral lipase activity (NLA) in lymphocytes of patients with primary hyperlipidemia (hypercholesterolemia or/and hypertriglyceridemia) were compared with that of an age-matched control group (blood donors). The specificity of lipase was confirmed by the use of cardiolipin the well known activator of acidic lipase. beta-D-glucuronidase activity was used as a marker of the lysosomal release reaction. ALA (by 33%) and beta-D-glucuronidase (by 55%) activity, but not NLA in lymphocytes of the group of hyperlipidemic patients, was significantly lower when compared to the control group. A negative correlation between the serum cholesterol level and ALA, NLA and beta-D-glucuronidase release from lymphocytes of hyperlipidemic subjects was observed. The serum HDL cholesterol level was positively correlated with ALA within this group. These results suggest that the high cholesterol level in serum can unspecifically supress ALA and (to the smaller degree) NLA activity in lymphocytes of hyperlipidemic subjects. The decrease of lipase activity may promote deposition of lipids in cells and the development of atherosclerosis. The parallel decrease of beta-D-glucuronidase activity in lymphocytes of hypercholesterolemic patients suggests the impairment of immune system in hypercholesterolemia.