The Pharmacodynamics Evalution Of Thpbs And The Role Of Cell Cycle Regulation In Pathophysiology Mechenism Of Schizophrenia

With the accelerated pace of modern work and life,people have to face more and more severe pressure of competition,which leads to the continuously rising prevalence of mental diseases and causing heavy economic and social burden onto the society and families.People have been looking for safe and effective drugs to treat mental illness.l-tetrahydropalmatine(l-THP),a tetrahydroprotoberberine(THPBS)alkaloid that is extracted from the Chinese herb Corydalis yanhusuo,has been used clinically to treat anxious insomnia in China for the past 40 years.Therefore,we synthesized the leading compounds l-Scoulerine(l-SLR)and l-Tetrahydroberberrubine(l-THBr),performed screening for their effect of anxiolytic and anti-addiction and explored their mechanisms,so as to provide the experimental basis for the development of safe and effective antipsychotic drugs.In the study of the pathogenesis of mental diseases,oligodendrocytes have attracted much attention.The main function of oligodendrocytes(OL)is the formation of myelin sheath around the axons of nerve fibers,which is involved in the rapid conduction of axons.In recent years,it has been found that there are abnormal development and differentiation deficits of oligodendrocytes in schizophrenia.Microarray analysis revealed that the expression of myelin related genes was decreased in the multiple brain regions in schizophrenia.It is suggested that the abnormal regulation of cell cycle may be an important factor leading to the differentiation deficits of oligodendrocytes in patients with schizophrenia.We intend to establish the oligodendrocyte damage model of schizophrenia,test the cell cycle and cycle regulation factors and clarify the effects of antipsychotic drug in cell cycle.The results are of great significance to reveal the pathophysiological process and treatment of schizophrenia.The investigation is composed of two parts: Part 1: The pharmacodynamics evalution of THPBsThe aim of this study was to evaluate the pharmacodynamic effects of the THPBs.We investigated the effects of l-SLR on methamphetamine induced abnormal behaviour in zebrafish and mice,as well as the anxiolytic effect and mechanism of l-THBr,using behavioral test and receptor binding assays.The pharmacodynamics of l-SLR on the abnormal behaviour of zebrafish and mice induced by methamphetamineWe investigated the effects of l-SLR on METH-induced anxiety-like behaviour in zebrafish and METH-induced addictive behaviour in mice.The zebrafish models were performed using novel tank experiment and mirror stimulating experiment.And the mice models included spontaneous activity,conditioned place preference and behavioral sensitization test.We found that:1.Acute administration of METH induced anxiety-like behaviour in zebrafish.In the novel tank test,METH induced a significant decrease in the number of total vertical transitions and time spent in the upper zone.Moreover,METH produced significant avoidance behavior showing increased swimming time in the central area and high speed movement in the mirror area in the mirror stimulation test;these anxiety-like changes were attenuated by l-SLR.2.Chronic administration of METH produced a steady increase in locomotor activity and conditione place preference in mice.l-SLR failed to reduce acute METH-induced hyperlocomotion,but attenuated chronic METH-induced behavioural sensitization and significantly blocked the expression of conditioned place preference induced by METH in mice.The research on the pharmacodynamics and mechanism of l-THBr in anxiolytic-effectThe purpose of this study was to evaluate the anxiolytic effect and mechanism of l-THBr.The experiment is mainly divided into two parts,elevated plus maze test and light dark box were performed to test the anxiolytic-like effects of l-THBr.Competitive binding assays were performed to examine the binding affinites of l-THBr to neurotransmitter receptors known to be involved in sedation,hypnosis and anxiety and cAMP and [35S]GTP?S assays were used to determine the agonist or antagonist properties of l-THBr at dopamine(D1,D2)or serotonin(5-HT)receptors.We found that:1.l-THBr-treatedrodents exhibit anxiolytic-like effects in the light/dark box and elevated plus-maze tests.l-THBr increased the ratio of entries into the open arms and the ratio of time spent in the open arms,and increased the number of transitions between the light/dark sides.The anxiolytic effect of l-THBr was inhibited by WAY-100635,a selective 5-HT1 A receptor antagonist,suggesting that the anxiolytic effect of l-THBr mainly through serotonin receptors.2.Radioligand binding assay showed that l-THBr mainly acts on dopamine and 5-serotonin receptor,and has no affinity with GABA receptor.c AMP detection and [35S]GTP?S experiments proved that l-THBr displays D1 and D2 antagonist and 5-HT1 A agonist properties.The purpose of this study was to investigate the role of the regulation of oligodendrocyte cell cycle in the pathophysiological process and treatment of schizophrenia.The experiment is composed of three parts.In the first experiment of this study,the cuprizong(CPZ)model was established,we examined the expression of cell cycle related genes and performed double labeling to calculate cell cycle exit index in the mice.In the second experiment,we evaluated effects of a CDK inhibitor flavopiridol(FLA)on CPZ-induced neuropathological changes and spatial working memory impairment in mice.In the third experiment,we detected the effects of antipsychotic drug quetiapine on the regulation of cell cycle in oligodendrocytes,RT-PCR assay was performed to test the expression of genes related to cell cycle after the chronic administration of quetiapine.1.Our results showed that CPZ administration up-regulated the expression of 16 cell cycle related genes,but down-regulated the expression of only one in the prefrontal cortex(PFC)of mice compared to control group.Most of the up-regulated genes are cell cycle positive regulators,and the only one down-regulated gene is believed to maintain genome stability.In addition,CPZ inhibited potential precursor cells exit from cell cycle.2.We evaluated effects of the CDK inhibitor flavopiridol(FLA)on CPZ-induced neuropathological changes and spatial working memory impairment in mice.FLA treatment for one week effectively attenuated the CPZ-induced increases in NG2 positive cells,microglia and astrocytes,alleviated the concurrent mature oligodendrocyte loss and myelin breakdown,and improved spatial working memory deficit in the CPZ-exposed mice.3.Antipsychotic drug quetiapine inhibits PDGF induced proliferation and also inhibits the reduction of cell cycle exit index induced by PDGF in primary cultured oligodendrocytes.Quetiapine does not induce the apoptosis of the cells at the effective doses.Chronic administration of quetiapine increases p21 expression significantly.Therefore,we hypothesized that quetiapine may regulate oligodendrocyte differentiation through the cell cycle arrest.In summary,we evaluated the anxiolytic and anti-addictive effects of the leading compounds l-Scoulerine(l-SLR)and l-Tetrahydroberberrubine(l-THBr),also examined the affinites of l-THBr to the neurotransmitter receptors.Zebrafish and mouse models were used to evaluate the effects of l-SLR on METH induced abnormal behaviour.Results showed that l-SLR was able to inhibit the METH induced anxiety-like behaviour in zebrafish and METH-induced addictive behavior in mice.l-THBr treated rodents exhibit anxiolytic-like effects in the light/dark box and elevated plus-maze tests.Moreover,l-THBr displayed D1 and D2 antagonist and 5-HT1 A agonist properties and had no affinity with GABA receptor.The present study Part 2: The role of the regulation effect of oligodendrocyte cell cycle in the pathophysiology and treatment of schizophrenia suggests that THPBs may be promising agents for the treatment of addiction and anxiety.We also investigate the role of the regulation of oligodendrocyte cycle in the pathogenesis and treatment of schizophrenia.The results indicat that cell cycle dysfunction of oligodendrocyte may be one of the important factors that contribute to the differentiation deficits in the schizophrenic.Antipsychotic drug quetiapine may promote the differentiation of oligodendrocytes by regulating cell cycle.The results are of great significance to reveal the pathophysiological process and treatment of schizophrenia.