Henry Morgane A, Alexis Maria N
Department of Fish Nutrition and Pathology, Institute of Aquaculture, Hellenic Centre for Marine Research, Aghios Kosmas, Elliniko 16604, Greece.
Vet Immunol Immunopathol. 2009 Aug 15;130(3-4):236-42. doi: 10.1016/j.vetimm.2009.02.014. Epub 2009 Feb 28.
Antimicrobial, anti-inflammatory and immunomodulating properties of lactoferrin have been demonstrated in mammals and in fish. However, in vivo, lactoferrin is digested by gastric pepsin treatment into the N-terminal derived peptide named lactoferricin. This has been so far overlooked in fish in vitro studies. The aim of the present study was to assess in vitro the effects of both lactoferricin and lactoferrin on the head kidney cells of European sea bass (Dicentrarchus labrax, L.) in order to determine their potential as dietary additives and to get some insight into their mode of action. In vitro lactoferricin decreased significantly the chemiluminescent response of head kidney cells but did not affect the zymosan-triggered chemiluminescence activity. On the other hand, a high concentration of lactoferrin directly stimulated chemiluminescence but reduced the zymosan-triggered chemiluminescence. The bactericidal activity of head kidney cells was also significantly diminished by pre-incubation with lactoferrin in a dose-dependent manner. Although no significant effect of lactoferricin or lactoferrin was evidenced on head kidney cellular viability, absent or negative effect on the priming of respiratory burst activity suggested that care should be taken when using lactoferrin in the diet of sea bass and high doses should be avoided. Hypotheses about the mechanisms of action of lactoferricin and lactoferrin are presented.
乳铁蛋白的抗菌、抗炎和免疫调节特性已在哺乳动物和鱼类中得到证实。然而，在体内，乳铁蛋白经胃蛋白酶处理后会被消化成名为乳铁蛋白肽的N端衍生肽。这一点在鱼类体外研究中一直被忽视。本研究的目的是在体外评估乳铁蛋白肽和乳铁蛋白对欧洲海鲈（Dicentrarchus labrax, L.）头肾细胞的影响，以确定它们作为饲料添加剂的潜力，并深入了解其作用方式。体外实验中，乳铁蛋白肽显著降低了头肾细胞的化学发光反应，但不影响酵母聚糖引发的化学发光活性。另一方面，高浓度的乳铁蛋白直接刺激化学发光，但降低了酵母聚糖引发的化学发光。头肾细胞的杀菌活性也因与乳铁蛋白预孵育而以剂量依赖的方式显著降低。虽然未证明乳铁蛋白肽或乳铁蛋白对头肾细胞活力有显著影响，但对呼吸爆发活性启动的缺失或负面影响表明，在海鲈饲料中使用乳铁蛋白时应谨慎，应避免高剂量使用。文中还提出了关于乳铁蛋白肽和乳铁蛋白作用机制的假设。
