The Mechanism Of Thioredoxin-1 Regulating Addiction Induced By Environmental Toxicant Morphine

Morphine is used to treat pain in clinic,however,long-term use of morphine will lead to tolerance and addiction.Long-term use of morphine leads to pathological changes in the related brain areas and produces related pathological behaviors,such as drug seeking,withdrawal and relapse.Morphine addiction is mainly involved in prefrontal cortex(PFC),ventral ventral tegmental area(VTA),nucleus accumbens(NAc),and hippocampus(Hip).Morphine addiction results in changes of dopaminergic,glutamatergic and y-aminobutyric acid(GABA)systems.With environmental pollution,ionizing radiation,alcoholism,smoking,will lead to oxidative stress.Thioredoxin-1(Trx-1)is a redox regulatory protein with multiple biological functions.Trx-1 can resist apoptosis,regulate glucocorticoid and endoplasmic reticulum stress,and immune response.However,morphine seriously endanger the health of human.Morphine cultivation will lead to the loss of water and soil.Morphine extraction will lead to river pollution and air pollution.Therefore,it is of great significance to explore the mechanism of morphine addiction for the health of the human.Therefore,we can use the reductive activity of thioredoxin-1 to protect human health from environmental toxicant morphine addiction.However,it is not clear whether Trx-1 is involved in regulating morphine addiction and its molecular mechanism.(1)Overexpression of Trx-1 transgenic(TG)mice resisted morphine induced conditioned place preference(CPP).In this experiment,wild type mice were randomly divided into two groups:wild type saline group and wild type morphine group.Overexpression of Trx-1 mice were randomly divided into two groups,transgenic mice saline group and transgenic mice morphine group.By using the mice CPP instrument and the behavior recording device,CPP induced by morphine in mice was dectected.The results showed that morphine induced CPP expression in wild type mice,but not in Trx-1 transgenic mice.This indicates that overexpression of Trx-1 inhibits morphine induced CPP.The expression of Trx-1 was increased by morphine in VTA,NAc,Hip and PFC,which was not increased further in Trx-1 TG mice.(2)The role of Trx-1 regulating the ? receptor.In the CPP model,Western Blot showed that the expression of[,receptor was decreased induced by morphine,while the expression of ?receptor was restored in TG mice.Trx-1 binds ? receptor in PC 12 cells by Co-Immunoprecipitation(CO-IP).Dithiothreitol or hydrogen peroxide regulated the interaction between Trx-1 and ? receptor in PC12 cells.(3)The role of Trx-1 regulating the transcription factors.In the morphine CPP model,the expression of cAMP-response element binding protein(CREB),AFosB,and Cyclin-dependent Kinase 5(CDK5)were increased by morphine in the VTA and NAc,which were not increased in TG mice.The level of p-eIF2a was decreased by morphine,while the level of p-eIF2a was restored in TG mice.The expressions of p-CREB and CDK5 were increased by morphine in Hip,which were not increased in TG mice.The expressions of AFosB and CDK5 were increased by morphine in PFC,which were not increased in TG mice.(4)The role of Trx-1 regulating the dopaminergic system.In the morphine CPP model,the expression of dopamine receptor 1(D1R),dopamine receptor 2(D2R)and tyrosine hydroxylase(TH)were increased by morphine in the VTA and NAc,which were not increased in TG mice.The expression of DIR and TH were increased by morphine in Hip and PFC,which were not increased in TG mice.(5)The role of Trx-1 regulating glutamatergic system.In the morphine CPP mode,the expression of NR2B and AMPAR were increased in the VTA,NAc and Hip,which were not increased in TG mice.The expression of VGLUT3 was decreased in the VTA,NAc and Hip,which were restored in TG mice.The expression of NR2B were increased in PFC,which were not increased in TG mice.(6)In the morphine CPP model,the number of synapse in VTA was increased significantly,and the number of synapse was increased in TG mice compared to wild type mice,but the number of synapse was not increased by morphine in TG mice.The expression of PSD-95 was increased in VTA,which was not further increased by morphine in TG mice.(7)The role of Trx-1 regulating GABAergic system.In the morphine CPP model,the expression of GABABR was decreased by morphine in the VTA,NAc,Hip and PFC,which was restored in TG mice.The leve of GABA in VTA and NAc were significantly decreased by morphine,which was restored in TG mice through using high performance liquid chromatography(HPLC).In conclusion,the study showed that overexpression of Trx-1 resists the CPP expression induced by morphine and inhibited changes of dopaminergic,glutamatergic,and GABAergic systems related with addiction in the VTA,NAc,Hip and PFC.Overexpression of Trx-1 blocked the increase of synapse in VTA.Thus,Trx-1 may be a target for treating reward effects induced by morphine.