Boucrot P, Bobin-Dubigeon C, Elkihel L, Letourneux Y, Jugé M, Gandemer G, Petit J Y
Laboratoire d'étude des interactions des molécules alimentaires, INRA, Nantes, France.
Fundam Clin Pharmacol. 1998;12(4):433-41. doi: 10.1111/j.1472-8206.1998.tb00968.x.
Compounds able to inhibit phospholipases A2 can be considered as potential anti-inflammatory drugs. In this respect, the inhibitory effect of the phospholipid analogue 1-decyl 2-octyl-rac-glycero-3-phosphocholine (decyloctyl-GPC) added to the culture medium of rat peritoneal macrophages stimulated with ionophore A23187 was determined. (a) The substrate of phospholipase A2 1-octadecanoyl 2-[14C]eicosatetraenoyl-sn-glycero-3-phosphocholine ([14C]20:4-GPC) was added to the culture medium. In macrophages + extracellular fluids, its hydrolysis at the 2-position, produced [14C]non-phosphorous lipids which reached 12% of the dose at 0.14 microM, 73% at 0.9 and > 90% at 1.6 microM; in experiments where macrophages and extracellular fluids were analyzed separately, decyloctyl-GPC initially added at 4 microM, significantly inhibited the release of [14C]fatty acids and the eicosanoid synthesis, demonstrating its ability to inhibit secreted and/or intracellular phospholipases A2. (b) Extracellular fluids were separated from the macrophages and incubated with [14C]20:4-GPC: 48% of the dose was hydrolyzed by extracellular fluid-associated secreted phospholipase A2 and decyloctyl-GPC at 3 microM, reduced this hydrolysis by 50%. (c) [3H]arachidonic acid ([3H]20:4) was added to the culture medium and was esterified in the macrophage membrane phospholipids. Activation of intracellular phospholipase A2 induced the release of [3H] fatty acids and eicosanoid synthesis. These releases were inhibited by 50% with decyloctyl-GPC added at 4 microM. (d) [3H]20:4 and [14C]20:4-GPC were added to the culture medium of the macrophages. [3H] and [14C] fatty acids and eicosanoids were released in macrophages or extracellular fluids. They were significantly reduced by the phospholipid analogue added at 4 microM. It is concluded that secreted and intracellular phospholipases A2 were both inhibited by decyloctyl-GPC which extensively reduced the 20:4 release from exogenous and membrane phospholipids and therefore eicosanoid synthesis.
能够抑制磷脂酶A2的化合物可被视为潜在的抗炎药物。在这方面，测定了添加到用离子载体A23187刺激的大鼠腹腔巨噬细胞培养基中的磷脂类似物1-癸基2-辛基-消旋甘油-3-磷酸胆碱（癸基辛基-GPC）的抑制作用。（a）将磷脂酶A2的底物1-十八烷酰基2-[14C]二十碳四烯酰基-sn-甘油-3-磷酸胆碱（[14C]20:4-GPC）添加到培养基中。在巨噬细胞+细胞外液中，其在2位的水解产生了[14C]无磷脂质，在0.14 microM时达到剂量的12%，在0.9 microM时达到73%，在1.6 microM时>90%；在分别分析巨噬细胞和细胞外液的实验中，最初以4 microM添加的癸基辛基-GPC显著抑制了[14C]脂肪酸的释放和类花生酸的合成，证明了其抑制分泌型和/或细胞内磷脂酶A2的能力。（b）将细胞外液与巨噬细胞分离，并用[14C]20:4-GPC孵育：48%的剂量被细胞外液相关的分泌型磷脂酶A2水解，3 microM的癸基辛基-GPC使这种水解减少了50%。（c）将[3H]花生四烯酸（[3H]20:4）添加到培养基中，并在巨噬细胞膜磷脂中酯化。细胞内磷脂酶A2的激活诱导了[3H]脂肪酸的释放和类花生酸的合成。添加4 microM的癸基辛基-GPC可使这些释放减少50%。（d）将[3H]20:4和[14C]20:4-GPC添加到巨噬细胞培养基中。[3H]和[14C]脂肪酸及类花生酸在巨噬细胞或细胞外液中释放。添加4 microM的磷脂类似物可使其显著减少。结论是，癸基辛基-GPC抑制了分泌型和细胞内磷脂酶A2，广泛减少了外源性和膜磷脂中20:4的释放，从而减少了类花生酸的合成。
