Effects of Yuanhu- Zhitong tablets on alcohol-induced conditioned place preference in mice

This study aimed at determining the synergistic effects of Yuanhu Zhitong tablets (YHZTP) on alcohol-induced conditioned place preference (CPP) in mice, in addition, the intervention mechanism was preliminarily explored based on traditional Chinese Medicine (TCM) network pharmacology on alcohol addiction.

Alcohol-induced CPP mice were used to evaluate the effects of either YHZTP or levo-tetrahydropalmatine (l-THP) plus imperatorin (IMP) administration on animal behavior. The network pharmacological strategy was used to establish the "compound-target" and "disease-drug-target" network. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed on the shared targets between the compound and the disease. Twelve algorithms on CytoHubba were used to find the hub genes that were verified by qPCR.

Systemic administration (2 g/kg, i.p.) of ethanol (EtOH) to mice was used to induce CPP. YHZTP On its own did not induce CPP or conditioned place aversion (CPA) at the doses of 0.3 g/kg or 0.6 g/kg (i.g.), but attenuated the acquisition and expression of EtOH-induce CPP in mice. In addition, YHZTP (0.3 or 0.6 g/kg) did not exhibit any effect on the motor activity of mice. Acquisition of alcohol-induced CPP was blocked by a combination of l-THP (5 mg/kg, i.g.) + IMP (2.5 mg/kg, i.g.) or l-THP (10 mg/kg, i.g.) + IMP (5 mg/kg, i.g.). However, the combination of l-THP (2.5 mg/kg, i.g.) + IMP (1.25 mg/kg, i.g.) or mono-administration of l-THP and IMP did not exhibit any effect on alcohol-induced CPP. YHZTP was also shown to reverse the up-regulation of Gabra1, Ptgs2, Mapk1, Mapk8, Mapk14, Nr3c, Prkca and Sirt1 genes and the down-regulation of Hhtr2a and Drd2 genes in the prefrontal cortex of EtOH induced CPP mice. These genes were associated with neuroactive ligand-receptor interactions, activation of the sphingolipid, calcium, cAMP, ErbB, NF-kappa B and MAPK signaling pathways.

YHZTP inhibits EtOH-induced CPP behavior in mice while a combination of l-THP and IMP exerts a synergistic effect on the reduction of EtOH-induced CPP. Possible pharmacological mechanisms include inhibition of the expression of inflammatory factors and regulation of neurotransmitter receptor levels. Therefore, YHZTP is a novel candidate for the treatment of alcohol addiction.