Effects of some aldehydes on brain microtubular protein

4-Hydroxynonenal is one of the main breakdown products of lipid peroxidation. It has an antiproliferative effect, which may partly be the consequence of an interaction with cytoskeletal structures. Its effects on microtubular protein are compared with those of homologous aldehydes with the same number of carbon atoms, and with that of benzaldehyde. Unlike the other aliphatic aldehydes, this latter aldehyde does not impair microtubular functions at every concentration in the range. Nonanal has the greatest effect on tubulin polymerization, whereas it only slightly impairs colchicine binding activity. 2-Nonenal and 4-hydroxynonenal have less inhibiting effect on tubulin polymerization; their effect on colchicine binding activity is dose-dependent. The targets of 4-hydroxynonenal on tubulin are -SH groups; the action mechanism of other aldehydes has not yet been identified.