Myricetin reduces 6-hydroxydopamine-induced dopamine neuron degeneration in rats.

The effects of myricetin on 6-hydroxydopamine (6-OHDA)-induced neurodegeneration in the substantia nigra-striatum system were investigated. By high-performance liquid chromatography electrochemical detection, we showed that the dopamine content in the striatum decreased after 6-OHDA treatment, which could be restored by myricetin. The immunohistochemistry and semiquantitative reverse transcription-PCR studies showed that myricetin could prevent the 6-OHDA-induced decrease of tyrosine hydroxylase positive neurons and the tyrosine hydroxylase mRNA expression in the substantia nigra. Perls' iron staining study further demonstrated that myricetin prevented the 6-OHDA-induced increase of iron-staining cells in the substantia nigra. These results suggested that the protective effects of myricetin on the toxicity of 6-OHDA could be attributed to the myricetin-suppressed iron toxicity.