Activation of tyrosine hydroxylase RNA expression by water extract of vernonia cinerea in nicotine-pretreated PC12 cells

Abstract

Background: Vernonia cinerea (VC) has been widely applied for smoking cessation. In tobacco users, the activation of dopaminergic neurons via nicotinic cholinergic receptors results in activated brain reward pathways by nicotine. However, molecular mechanism of this Vernonia species in tobacco-addiction is unclear. Objective: The present study aimed to reveal a mechanism whether tyrosine hydroxylase (TH), a rate limiting enzyme in dopaminergic pathway, involved in the bioactivity of Vernonia cinerea on a cellular model of nicotine addict. Materials and Methods: Rat pheochromocytoma 12 (PC12), dopaminergic cell line, was pre-treated and post-treated under medium containing nicotine and medium containing water extract of Vernonia cinerea, respectively. Treated cells were analyzed for the levels of transcripts of TH to determine the functional alteration of genes encoding for this enzyme. Results: TH transcripts was up-regulated under treatment of various concentration of Vernonia extract. Upon cell cytotoxicity, its activation was not resulted from the promotion of cell death. Conclusion: The present study was firstly described the TH activation of bioactive substance in the water extract of Vernonia cinerea. © JOURNAL OF THE MEDICAL ASSOCIATION OF THAILAND| 2019.