{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,9]],"date-time":"2026-02-09T23:08:13Z","timestamp":1770678493346,"version":"3.49.0"},"reference-count":48,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2017,1,11]],"date-time":"2017-01-11T00:00:00Z","timestamp":1484092800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>The potential role of non-antibiotic medicinal products in the treatment of multidrug-resistant Gram-negative bacteria has recently been investigated. It is highly likely that the presence of efflux pumps may be one of the reasons for the weak activity of non-antibiotics, as in the case of some non-steroidal anti-inflammatory drugs (NSAIDs), against Gram-negative rods. The activity of eight drugs of potential non-antibiotic activity, active substance standards, and relevant medicinal products were analysed with and without of efflux pump inhibitors against 180 strains of five Gram-negative rod species by minimum inhibitory concentration (MIC) value determination in the presence of 1 mM MgSO4. Furthermore, the influence of non-antibiotics on the susceptibility of clinical strains to quinolones with or without PA\u03b2N (Phe-Arg-\u03b2-naphthylamide) was investigated. The impacts of PA\u03b2N on the susceptibility of bacteria to non-antibiotics suggests that amitriptyline, alendronate, nicergoline, and ticlopidine are substrates of efflux pumps in Gram-negative rods. Amitriptyline\/Amitriptylinum showed the highest direct antibacterial activity, with MICs ranging 100\u2013800 mg\/L against all studied species. Significant decreases in the MIC values of other active substances (acyclovir, atorvastatin, and famotidine) tested with pump inhibitors were not observed. The investigated non-antibiotic medicinal products did not alter the MICs of quinolones in the absence and in the presence of PA\u03b2N to the studied clinical strains of five groups of species.<\/jats:p>","DOI":"10.3390\/molecules22010114","type":"journal-article","created":{"date-parts":[[2017,1,11]],"date-time":"2017-01-11T10:36:49Z","timestamp":1484131009000},"page":"114","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":27,"title":["The Impact of Efflux Pump Inhibitors on the Activity of Selected Non-Antibiotic Medicinal Products against Gram-Negative Bacteria"],"prefix":"10.3390","volume":"22","author":[{"given":"Agnieszka","family":"Laudy","sequence":"first","affiliation":[{"name":"Department of Pharmaceutical Microbiology, Medical University of Warsaw, Oczki 3 Str., 02-007 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ewa","family":"Kuli\u0144ska","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Microbiology, Medical University of Warsaw, Oczki 3 Str., 02-007 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Stefan","family":"Tyski","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Microbiology, Medical University of Warsaw, Oczki 3 Str., 02-007 Warsaw, Poland"},{"name":"Department of Antibiotics and Microbiology, National Medicines Institute, Che\u0142mska 30\/34 Str., 00-725 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,1,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"340","DOI":"10.1111\/j.1574-6976.2011.00290.x","article-title":"Broad-specificity efflux pumps and their role in multidrug resistance of Gram-negative bacteria","volume":"36","author":"Nikaido","year":"2012","journal-title":"FEMS Microbiol. 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