Szeszel-Fedorowicz W, Rosiński G, Issberner J, Osborne R, Janssen I, De Loof A, Konopińska D
Faculty of Chemistry, University of Wrocław, Wrocław, Poland.
Acta Pol Pharm. 2000 Nov;57 Suppl:88-9.
Novel analogs, modified by L- or D- phenylglycine and p-substituted derivatives, of the neuromodulator proctolin (Arg-Tyr-Leu-Pro-Thr) and of the Trypsin Modulating Oostatic Factor from the gray flesh fly Neobellieria bullata (Neb-TMOF-Asn-Pro-Thr-Asn-Leu-His) were synthesized and checked for activity. Proctolin analogs were modified at position 2: Arg-Phg-Leu-Pro-Thr (I), Arg-D-Phg-Leu-Pro-Thr (II), Arg-Phg(p-OH)-Leu-Pro-Thr (III), Arg-D-Phg(p-OH)-Leu-Pro-Thr (IV), Arg-Phg(p-NO2)-Leu-Pro-Thr (V) Arg-D-Phg(p-NO2)-Leu-Pro-Thr (VI), Arg-Phg(p-NH2)-Leu-Pro-Thr (VII), Arg-D-Phg(p-NH2)-Leu-Pro-Thr (VIII), Arg-Phg(p-N,N-di-Me)-Leu-Pro-Thr (IX), Arg-D-Phg(pp-N,N-di-Me)-Leu-Pro-Thr (X) while analogs of Neb-TMOF underwent modifications at position 6: Asn-Pro-Thr-Asn-Leu-Phg(p-NO2) (XI), Asn-Pro-Thr-Asn-Leu-D-Phg(p-NO2) (XII), Asn-Pro-Thr-Asn-Leu-Phg(p-NH2) (XIII), Asn-Pro-Thr-Asn-Leu-D-Phg(p-NH2) (XIV), Asn-Pro-Thr-Asn-Leu-Phg(p-N,N-di-Me) (XV), Asn-Pro-Thr-Asn-Leu-D-Phg(p-N,N-di-Me) (XVI). Earlier studies on proctolin demonstrated that the presence of the -CH2- group between C-alpha and the phenyl ring at position 2 of the peptide chain is important for the myotropic activity. Based on these results, we replaced Tyr at position 2 by different phenylglycine derivatives, lacking the methylene group at the side chain. Myotropic activity of the proctolin analogs was assayed in vitro on the semi-isolated heart of the mealworm Tenebrio molitor and on the foregut of the locust Schistocerca gregaria. All analogs (I-X) were practically inactive. For Neb-TMOF, it was previously demonstrated that the exchange of His-6 by p-substituted Phe-derivatives, especially by Phe(p-NH2), an amino acid containing a basic function, results into analogs which inhibit trypsin biosynthesis in the gray fleshfly. For this reason these new Neb-TMOF analogs with L- or D-phenylglycine p-substituted derivatives at position 6, were developed and tested (in vivo) in the trypsin biosynthesis assay of the gray fleshfly N. bullata. Only analogs XV and XVI slightly inhibited trypsin biosynthesis in the midgut. Because more than 50% of the injected animals died and none of the surviving animals ate much of the liver meal, the lower trypsin level in the gut might be a indirect effect. Other peptides (XI-XIV) had no effect on the level of trypsin biosynthesis in the midgut.
合成了经L-或D-苯甘氨酸及对位取代衍生物修饰的神经调质原肠促动素（精氨酸-酪氨酸-亮氨酸-脯氨酸-苏氨酸）和来自灰肉蝇（新贝拉丽蝇）的胰蛋白酶调节抑卵因子（Neb-TMOF-天冬酰胺-脯氨酸-苏氨酸-天冬酰胺-亮氨酸-组氨酸）的新型类似物，并检测了其活性。原肠促动素类似物在第2位进行了修饰：精氨酸-苯甘氨酸-亮氨酸-脯氨酸-苏氨酸（I）、精氨酸-D-苯甘氨酸-亮氨酸-脯氨酸-苏氨酸（II）、精氨酸-苯甘氨酸（对羟基）-亮氨酸-脯氨酸-苏氨酸（III）、精氨酸-D-苯甘氨酸（对羟基）-亮氨酸-脯氨酸-苏氨酸（IV）、精氨酸-苯甘氨酸（对硝基）-亮氨酸-脯氨酸-苏氨酸（V）、精氨酸-D-苯甘氨酸（对硝基）-亮氨酸-脯氨酸-苏氨酸（VI）、精氨酸-苯甘氨酸（对氨基）-亮氨酸-脯氨酸-苏氨酸（VII）、精氨酸-D-苯甘氨酸（对氨基）-亮氨酸-脯氨酸-苏氨酸（VIII）、精氨酸-苯甘氨酸（对N,N-二甲基）-亮氨酸-脯氨酸-苏氨酸（IX）、精氨酸-D-苯甘氨酸（对N,N-二甲基）-亮氨酸-脯氨酸-苏氨酸（X），而Neb-TMOF类似物在第6位进行了修饰：天冬酰胺-脯氨酸-苏氨酸-天冬酰胺-亮氨酸-苯甘氨酸（对硝基）（XI）、天冬酰胺-脯氨酸-苏氨酸-天冬酰胺-亮氨酸-D-苯甘氨酸（对硝基）（XII）、天冬酰胺-脯氨酸-苏氨酸-天冬酰胺-亮氨酸-苯甘氨酸（对氨基）（XIII）、天冬酰胺-脯氨酸-苏氨酸-天冬酰胺-亮氨酸-D-苯甘氨酸（对氨基）（XIV）、天冬酰胺-脯氨酸-苏氨酸-天冬酰胺-亮氨酸-苯甘氨酸（对N,N-二甲基）（XV）、天冬酰胺-脯氨酸-苏氨酸-天冬酰胺-亮氨酸-D-苯甘氨酸（对N,N-二甲基）（XVI）。早期对原肠促动素的研究表明，肽链第2位的α-碳原子与苯环之间存在-CH2-基团对肌动活性很重要。基于这些结果，我们将第2位的酪氨酸替换为侧链缺乏亚甲基的不同苯甘氨酸衍生物。在黄粉虫（黄粉甲）的半离体心脏和沙漠蝗（飞蝗）的前肠上对原肠促动素类似物的肌动活性进行了体外测定。所有类似物（I-X）实际上均无活性。对于Neb-TMOF，先前已证明用对位取代的苯丙氨酸衍生物，尤其是含碱性官能团的苯丙氨酸（对氨基）取代第6位的组氨酸，可产生抑制灰肉蝇胰蛋白酶生物合成的类似物。因此，开发了这些在第6位带有L-或D-苯甘氨酸对位取代衍生物的新型Neb-TMOF类似物，并在灰肉蝇的胰蛋白酶生物合成测定中进行了（体内）测试。只有类似物XV和XVI对中肠中的胰蛋白酶生物合成有轻微抑制作用。由于超过50%的注射动物死亡，且存活的动物均未大量食用肝粉，肠道中较低的胰蛋白酶水平可能是一种间接效应。其他肽（XI-XIV）对中肠中的胰蛋白酶生物合成水平没有影响。
