Modulation of membrane physical properties by natural insecticidal ketones

MIGUEL, V.; SÁNCHEZ-BORZONE, M.E.; MARIANI, M.E.; GARCÍA, D.A.

BIOPHYSICAL CHEMISTRY

ELSEVIER SCIENCE BV

Año: 2021 vol. 269

0301-4622

The insecticidal activity of Mentha oil and its main components has been tested andestablished for various insects/pests. Several mint ketones have demonstrated to acton GABA A receptors (GABA A -R), a transmembrane channel target of severalimportant insecticides whose activity can be modulated by surface-active compoundsand by changes in the physical properties of the lipid membrane. In the present work,we analyze the capacity of monoterpenic ketones most commonly found in Menthaspecies, pulegone and menthone, to interact with DPPC membranes by moleculardynamics (MD) simulations and Langmuir monolayers. The experimental resultsindicate that the presence of menthone and pulegone in the subphase modify theinterfacial characteristics of DPPC isotherms. The changes were reflected asexpansion of the isotherms and disappearance or bringing forward of DPPC phasetransition. MD simulation corroborate these results and indicate that both ketones arelocated at the region of the carbonyl group, at the interface with the acyl chains. Ketoneintercalation between lipid molecules would induce an increasing intermolecularinteraction, diminishing the film elasticity and causing an ordering effect. Our resultssuggest that the insecticidal activity of both ketones could involve their interaction withlipid molecules causing disturbance of the cell membrane as postulated for severallarvicide compounds, or at least modulating the receptor surrounding