Abstract
Lysophospholipase activity in brain subcellular fractions was measured by the release of myristic acid from 1-myristoylglycerophosphocholine or through the formation of [32P]glycerophosphocholine from [32P]lysophosphatidylcholine. Although the lysophospholipase activity was highest in microsomes, considerable enzyme activity was also found in other subcellular membrane fractions. The pH optimum for the microsomal enzyme was around 7, whereas the synaptosomes and non-synaptic plasma membranes exhibited a pH maximum around 8. Although the enzyme did not require divalent cations for activity, divalent cations (1 mM) such as Hg2+, Cu2+, and Zn2+ inhibited potently the enzyme activity. Enzyme activity was also partially inhibited by both saturated and polyunsaturated fatty acids (25–200 μM), and the inhibition seemed to be greater in the membrane than in the cytosolic fractions. Ionic detergents such as deoxycholate and taurocholate inhibited the lysophospholipase. On the other hand, the effect of Triton X-100 was biphasic, i.e., stimulation at concentrations below 100 μg/mg protein and inhibition at higher concentrations. Addition of cholesterol (50–250 μg/ml), but not cholesteryl esters, also potently inhibited enzyme activity. The presence of active lysophospholipase(s) in brain is probably an important mechanism for preventing unnecessary accumulation of lysophospholipids which may exert a deleterious effect on the membranes because, of their detergent properties.
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Sun, G. Y., Su, K. L., Der, O. M., and Tang, W. 1979. Enzymic regulation of arachidonate metabolism in brain membrane phosphoglycerides. Lipids 14:229–235.
Weltzien, H. U. 1979. Cytolytic and membrane-perturbing properties of lysophosphatidylcholine. Biochim. Biophys. Acta 559:259–287.
Shier, W. T., Baldwin, J. H., Nilsen-Hamilton, M., Hamilton, R. T., and Thanassi, N. M. 1976. Regulation of guanylate and adenylate cyclase activities by lysolecithin. Proc. Natl. Acad. Sci. (USA) 73:1586–1590.
Van den Bosch, H. and Van den Besselaar, A. M. H. P. 1978. Intracellular formation and removal of lysophospholipids, Pages 59–75,in C. Galli and G. Porcellati (eds.) Advances in Prostaglandin and Thromboxanes Research, Raven Press, New York.
Van den Bosch, H. 1980. Intracellular phospholipases A. Biochim. Biophys. Acta 604:191–246.
De Jong, J. G. N., Van den Bosch, H., Rejken, D., and Van Deenen, L. L. M. 1974. Studies on lysophospholipases. III. The complete purification of two proteins with lysophospholipase activity from beef liver. Biochim. Biophys. Acta 369:50–63.
Van den Bosch, H., and De Jong, J. G. N. 1975. Studies on lysophospholipases. IV. The subcellular distribution of two lysolecithinhydrolyzing enzymes in beef liver. Biochim. Biophys. Acta 398:244–257.
Leibovitz-BenGershon, Z., Kobiler, I., and Gatt, S. 1972. Lysophospholipases of rat brain. J. Biol. Chem. 247:6840–6847.
Leibovitz-BenGershon, Z., and Gatt, S. 1974. Lysolecithinase of rat brain. Further analysis of the effect of substrate on the particulate and microsomal enzyme. J. Biol. Chem. 249:1525–1529.
Gross, R. W., and Sobel, B. E. 1983. Rabbit myocardial cytosolic lysophospholipase. Purification, characterization, and competitive inhibition byl-palmitoyl carnitine. J. Biol. Chem. 258:5221–5226.
Huang, H-M., and Sun, G. Y. 1984. Properties of two plasma membrane fractions isolated from rat brain. Fed. Proc. 43:773 (Abstr).
Sottocasa, G. L., Kuylenstierna, B., Ernster, L., and Bergstrand, A. 1967. An electron transport system associated with the outer membrane of liver mitochondria. A biochemical and morphological study. J. Cell Biol. 32:415–438.
Anner, B., and Moosmayer, M. 1975. Rapid determination of inorganic phosphate in biological systems by a highly sensitive photometric method. Analyt. Biochem. 65:305–309.
Muszbek, L., Szabo, T., and Fesus, L. 1977. A highly sensitive method for the measurement of ATPase activity. Analyt. Biochem. 77:286–288.
Sun, A. Y., and Samorajski, T. 1970. Effects of ethanol on the activity of adenosine triphosphatase and acetylcholinesterase in synaptosomes isolated from guinea pig brain. J. Neurochem. 17:1365–1372.
Lowry, O. H., Rosebrough, N. J., Farr, A. L., and Randall, R. 1951. Protein measurement with folin phenol reagent. J. Biol. Chem. 193:265–275.
Strosznajder, J., Foudin, L., Tang, W., and Sun, G. Y. 1983. Serum albumin washing specifically enhances arachidonate incorporation into synaptosomal phosphatidylinositols. J. Neurochem. 40:84–90.
Franson, R. C., and Van den Bosch, H. 1982. Lysophospholipase activity of bovine adrenal medulla. Biochim. Biophys. Acta 711:75–82.
Chen, D-E., White, A. A. Tumbleson, M. E., and Sun, G. Y. 1985. Metabolism of lysophosphatidylcholine by swine platelets. Lipids 20:133–140.
De Jong, J. G. N., Van den Bosch, H., Aarsman, A. J., and Van Deenen, L. L. M. 1973. Studies on lysophospholipases. II. Substrate specificity of a lysolecithin hydrolyzing carboxylesterase from beef pancreas. Biochim. Biophys. Acta 296:105–115.
Gunawan, J., and Debuch, H. 1982. Lysoplasmalogenase—A microsomal enzyme from rat brain. J. Neurochem. 39:693–699.
Klopfenstein, W. E., deKruff, B., Verkleij, A. J., Demel, R. A., and van Deenen, L. L. M. 1974. Differential scanning colorimetry on mixtures of lecithin, lysolecithin and cholesterol. Chem. Phys. Lipid 13:215–222.
Kitagawa, T., Inoble, K., and Nojima, S. 1976. Cholesterollysolecithin complex. J. Biochem. (Tokyo) 79:1123–1133.
Ramsammy, L. S., and Brockerhoff, H. 1982. Lysophosphatidylcholine-cholesterol complex. J. Biol. Chem. 257:3570–3574.
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Sun, G.Y., Tang, W., Huang, S.FL. et al. Lysophospholipase activity in rat brain subcellular fractions. Neurochem Res 12, 451–458 (1987). https://doi.org/10.1007/BF00972297
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DOI: https://doi.org/10.1007/BF00972297