Inhibition of lipoprotein lipolysis by polyarginine and evaluation of the mechanism of its interaction with lipoprotein lipase
Klimov, A.N.; Serrano, D.S.; Kliueva, N.N.; Soliternova, I.B.; Nikul'cheva, N.G.
Biokhimiia 50(5): 804-813
1985
ISSN/ISBN: 0320-9725 PMID: 4005323 Document Number: 261427
It was found that polyarginine (Mr 40 000-60 000) is a strong inhibitor of the lipoprotein lipase activity in vivo and in vitro. The inhibitory effect in vivo was observed after a single intravenous injection of 0.85-3.5 mg/kg to rabbits, that in vitro at the polypeptide concentration of greater than or equal to 2.5 micrograms/ml. Within the first few hours after intravenous injection of polyarginine hyperlipidemia occurred with an obvious increase in the plasma triglyceride and VLDL fractions and a slight decrease of the LDL and HDL fractions. These changes typical for reduced lipoprotein lipolysis were due to the formation of a polyarginine-heparin complex, on the one hand, and to the formation of a polyarginine-enzyme complex devoid of the lipolytic properties, on the other. The inhibitory effect of polyarginine on lipoprotein lipase is related to the whole polypeptide molecule or its large fragment, since arginine and metformine (bi-guanidine compound) have no effect on the enzyme activity.