Barrero M A Ospina, Pietralonga P A G, Schwarz D G G, Silva A, Paula S O, Moreira M A S
Laboratório de Doenças Bacterianas, Setor de Medicina Veterinária Preventiva e Saúde Pública (SMVPSP), Departamento de Veterinária (DVT), Universidade Federal de Viçosa (UFV) Campus Universitário, 36570-000, Viçosa, Minas Gerais, Brazil.
Laboratório de Virologia Animal, SMVPSP, DVT, UFV, Viçosa, Minas Gerais, Brazil.
Res Vet Sci. 2014 Oct;97(2):176-81. doi: 10.1016/j.rvsc.2014.05.013. Epub 2014 Jun 6.
The multidrug efflux system in bacteria can reduce antibiotic concentration inside the cell, leading to failure in the treatment of bacterial diseases. This study evaluated the influence of two efflux pump inhibitors (EPIs), phenylalanine arginyl ß-naphthylamide (PAßN) and 1-(1-naphthylmethyl)-piperazine (NMP), on the gene expression of three multidrug efflux systems, AcrAB, AcrEF and EmrAB in Escherichia coli bovine mastitis isolates resistant to ampicillin and sulfamethoxazole/trimethoprim simultaneously. Each isolate had at least three multidrug efflux system genes. The acrA and acrB had the lowest expression levels in all treatments, while the emrA or emrB showed the highest expression levels in the presence of ampicillin, sulfamethoxazole/trimethoprim, PAβN and NMP. EPIs also contributed to the decrease in arcF expression when used in combination with ampicillin treatment. Since PAßN showed stronger effects than NMP, it may serve as an alternative to assist in the antimicrobial therapy of mastitis.
细菌中的多药外排系统可降低细胞内抗生素浓度，导致细菌性疾病治疗失败。本研究评估了两种外排泵抑制剂（EPI），苯丙氨酸精氨酰β-萘酰胺（PAβN）和1-（1-萘甲基）哌嗪（NMP），对同时耐氨苄西林和磺胺甲恶唑/甲氧苄啶的大肠杆菌牛乳腺炎分离株中三种多药外排系统AcrAB、AcrEF和EmrAB基因表达的影响。每个分离株至少有三个多药外排系统基因。在所有处理中，acrA和acrB的表达水平最低，而在氨苄西林、磺胺甲恶唑/甲氧苄啶、PAβN和NMP存在的情况下，emrA或emrB的表达水平最高。当与氨苄西林联合使用时，EPI也有助于降低arcF的表达。由于PAβN的效果比NMP更强，它可能作为辅助乳腺炎抗菌治疗的替代药物。
