Curcubiturils as cholesterol carrier in biomembrane model systems

• Grant number: 11/00850-9
• Support Opportunities: Regular Research Grants
• Start date: May 01, 2011
• End date: April 30, 2012
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Maria Elisabete Darbello Zaniquelli
• Grantee: Maria Elisabete Darbello Zaniquelli
• Host Institution: Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto (FFCLRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Associated researchers: Grégoire Jean-François Demets

Abstract

Cholesterol is essential in different biochemical processes, although high concentrations are harmful to our body. There is a pulmonary pathology, acute respiratory distress syndrome (ARDS), which promotes a high cholesterol level. It is directly linked to the surfactant pulmonary system (SP) that constitutes a monolayer covering the alveolar surface and presents a complex composition containing lipids and proteins. Dipalmitoylphosphatidylcholine (DPPC) is the major molecular species among the lipids. Palmitoyl-oleylphosphatidylglycerol is important because it provides peculiar mechanical properties to the interface, due to its insaturation. The main SP function is to decrease the surface tension, avoiding the collapse alveolar during the expiration. It is known that in a non healthy person, the cholesterol level in the SP is highly increased. Therefore it is important to study the effect of cholesterol in biomembrane model systems and its elimination by different compounds which allow its transport within the body. Recently it was demonstrated the formation of soluble cholesterol compounds with methyl-b-cyclodextrin. This proposal aims to study the interaction of cholesterol with non-toxic cucurbiturils, poly(glycolurils), also able to form inclusion compounds. The study will be carried out with Langmuir monolayers as model systems for the alveolar membrane. The monolayers will be composed of DPPC and DPPC/POPG with different amounts of cholesterol in the absence and presence of cucurbiturils. Surface dilatational rheology, fluorescence microscopy and surface pressure-area isotherms measured at the Langmuir trough will be the techniques employed in the development of this proposal. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

TOVANI, CAMILA BUSSOLA; VENTRICI DE SOUZA, JOAO FRANCISCO; CAVALLINI, THIAGO DE SOUZA; DEMETS, GREGOIRE JEAN-FRANCOIS; ITO, AMANDO; BARIONI, MARINA BERARDI; PAZIN, WALLANCE MOREIRA; DARBELLO ZANIQUELLI, MARIA ELISABETE. Comparison between cucurbiturils and beta-cyclodextrin interactions with cholesterol molecules present in Langmuir monolayers used as a biomembrane model. COLLOIDS AND SURFACES B-BIOINTERFACES, v. 111, p. 398-406, NOV 1 2013. (11/00850-9, 09/54044-3)