Proof of pore formation and biophysical perturbations through a 2D amoxicillin-lipid membrane interaction approach

• Type: Article in International Scientific Journal
• Date: 2017

Authors

Lopes, D (Author) Other; Nunes, C (Author) Other; Fontaine, P (Author) Other; Sarmento, B (Author) Other; Salette Reis (Author) FFUP

Journal

Title: Biochimica et Biophysica Acta: Biomembranes

Vol. 1859

Pages: 803-812

ISSN: 0005-2736

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 6 Citations

Scopus - 11 Citations

Other information

Authenticus ID: P-00M-F8C

DOI: 10.1016/j.bbamem.2017.01.031

Abstract (EN): Amoxicillin is a worldwide used antibiotic, and it is classified as a first-line drug against Helicobacter pylori gastric infections. However, the current treatment of these infections has several limitations, such as the side effects and the low therapeutic compliance. Amoxicillin has been associated with gastrointestinal and renal side effects, with higher toxicity when the pH is lower. By considering this association and the well-known pH gradient of the gastric mucosa, this work aims to evaluate the influence of pH on the toxicity of amoxicillin. For that purpose, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) monolayers were used since phosphatidylcholines are the most common phospholipid headgroup of biological membranes. To have insight of the effects of amoxicillin, different techniques were employed, namely, isotherm measurements, infrared reflection-absorption spectroscopy, grazing incident X-ray diffraction and Brewster angle microscopy. The monolayers of DPPC spread onto different buffer solutions (pH 1.2, pH 5 and pH 7.4) showed different structural and packing properties. The interaction with amoxicillin also depended on the pH. At pH 7.4, the highest effect was visualized at lower pressures, with partial restoration of the biophysical properties of the monolayer at 30 mN.m(-1). A higher perturbation is shown at acidic pH, in which pores were visualized by Brewster angle microscopy. These perturbations may ultimately be related with amoxicillin toxicity.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10