Effective protection of biological membranes against photo-oxidative damage: Polymeric antioxidant forming a protecting shield over the membrane

Author(s)

Mertins, Omar ; Mathews, Patrick D. ; Gomide, Andreza B. ; Baptista, Mauricio S. ; Itri, Rosangela

• Document type: Journal article
• Source: BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES; v. 1848, n. 10, p. 8-pg., 2015-10-01.

Abstract

We have prepared a chitosan polymer modified with gallic acid in order to develop an efficient protection strategy biological membranes against photodamage. Lipid bilayers were challenged with photoinduced damage by photosensitization with methylene blue, which usually causes formation of hydroperoxides, increasing area per lipid, and afterwards allowing leakage of internal materials. The damage was delayed by a solution of gallic acid in a concentration dependent manner, but further suppressed by the polymer at very low concentrations. The membrane of giant unilamellar vesicles was covered with this modified macromolecule leading to a powerful shield against singlet oxygen and thus effectively protecting the lipid membrane from oxidative stress. The results have proven the discovery of a promising strategy for photo protection of biological membranes. (C) 2015 Elsevier B.V. All rights reserved. (AU)

• FAPESP's process: 12/50680-5 - Photosensitization in life sciences
• Grantee: Mauricio da Silva Baptista
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 10/18163-5 - Membrane photo-protection as investigated by optical microscopy on giant unilamellar vesicles.
• Grantee: Omar Mertins
• Support Opportunities: Scholarships in Brazil - Post-Doctoral