Basabe-Tuero Liliana, Ayala Lázara, Espinosa Ivette, Machín Yeleiny, Coto Liany, Duarte Carlos, Piloto Soraya, Morales Antonio, Rodrigo Osmany, Diago David, Sosa Iliana, Estrada Mario Pablo, Martínez Rebeca
Metabolic Modifiers for Aquaculture, Agricultural Biotechnology Department, Center for Genetic Engineering and Biotechnology (CIGB), 31st Avenue and 190, Havana 10600, Cuba.
Institute of Animal Science (ICA), Carretera Central km 47 ½, San José de las Lajas, Mayabeque 32700, Cuba.
Res Vet Sci. 2025 Mar;184:105523. doi: 10.1016/j.rvsc.2024.105523. Epub 2024 Dec 26.
Porcine respiratory diseases have a huge economic impact on pig production. The highest incidence of these diseases is commonly linked to Streptococcus suis, Pasteurella multocida and Bordetella bronchiseptica, some of which are zoonotic posing a risk to human health. The inappropriate and excessive use of conventional antibiotics, as usual procedure for treating respiratory diseases in pigs, has generated the emergence of antimicrobial resistance (AMR), which urgently requires the development of alternative approaches to current antimicrobials. Antimicrobial peptides (AMPs) have rapidly garnered interest as novel therapeutic candidates. Oreochromicin-2 (Oreoch-2), an AMP previously isolated from Oreochromis niloticus gills, has shown broad antibacterial properties against several species. However, studies about its effect on porcine respiratory pathogens and its potential use for the treatment of swine respiratory diseases are not available. In this work we determined the in vitro antimicrobial activity of the peptide against S. suis by a broth microdilution method. Oreoch-2 showed a MIC of 3.13 μM against this pathogen. For in vivo experiments, Yorkshire x Landrace crossbred (LYxL35) weaning pigs aged 30-33 days were allocated in pens containing ten pigs each. To study the influence of the peptide on health status, a total clinical score was determined. The administration of Oreoch-2 improved the clinical behavior of the animals, similar to the conventional antibiotic shotapen, respect to the placebo group. A reduction of bacterial loads in the respiratory tract and lungs was observed in Oreoch-2-treated animals as compared to the placebo group. It was shown that peptide treated-piglets displayed significantly higher serum IgG concentration compared to the control group. These results demonstrated Oreoch-2 potential as an antimicrobial and immunostimulant drug candidate against respiratory diseases in pigs.
猪呼吸道疾病对养猪业造成了巨大的经济影响。这些疾病的最高发病率通常与猪链球菌、多杀性巴氏杆菌和支气管败血波氏杆菌有关，其中一些是人畜共患病，对人类健康构成风险。作为治疗猪呼吸道疾病的常规方法，常规抗生素的不当和过度使用导致了抗菌药物耐药性（AMR）的出现，这迫切需要开发替代当前抗菌药物的方法。抗菌肽（AMPs）作为新型治疗候选物迅速引起了人们的关注。Oreochromicin-2（Oreoch-2）是一种先前从尼罗罗非鱼鳃中分离出的抗菌肽，已显示出对多种物种具有广泛的抗菌特性。然而，关于其对猪呼吸道病原体的作用及其在治疗猪呼吸道疾病中的潜在用途的研究尚未见报道。在这项工作中，我们通过肉汤微量稀释法测定了该肽对猪链球菌的体外抗菌活性。Oreoch-2对该病原体的最低抑菌浓度（MIC）为3.13 μM。对于体内实验，将30-33日龄的约克夏×长白杂交（LYxL35）断奶仔猪分配到每栏饲养十头猪的猪舍中。为了研究该肽对健康状况的影响，测定了总临床评分。与安慰剂组相比，Oreoch-2的给药改善了动物的临床行为，类似于常规抗生素舒他西林。与安慰剂组相比，在接受Oreoch-2治疗的动物中观察到呼吸道和肺部细菌载量的降低。结果表明，与对照组相比，肽处理的仔猪血清IgG浓度显著更高。这些结果证明了Oreoch-2作为治疗猪呼吸道疾病的抗菌和免疫刺激药物候选物的潜力。
