Regulation And Possible Mechanism Of HDAC2 In Bisphenol A-damaged Learning And Memory

Bisphenol A(Bisphenol A)scientific name is 2,2-bis(4-hydroxyphenyl)propane,which is an organic compound containing two phenol groups.Bisphenol A is an important industrial chemical,mainly used as an intermediate in the production of polycarbonate and epoxy resins.Bisphenol A is widely used in daily life in plastics,food packaging,dental sealants and other fields.The main way of human exposure to Bisphenol A is from food intake.At present,Bisphenol A residue is an important food safety issue.However,more and more epidemiological studies show that Bisphenol A is neurotoxic,and the role of epigenetic regulation in Bisphenol A-induced neurotoxicity is still unclear.Therefore,this article wants to explore the mechanism of epigenetic regulation of Bisphenol Ainduced neurotoxicity.Methods and results: 1.Cells explore the neurotoxicity of Bisphenol A and its epigenetic regulatory mechanism.First,the effect of Bisphenol A exposure on the protrusion of rat adrenal medullary pheochromocytoma(PC12 cells)was explored.PC12 cells were exposed to 1,10 ?M Bisphenol A for 24 h to observe the effect of bisphenol A on the protrusion of cells.The results showed that Bisphenol A exposure significantly inhibited the growth of PC12 cell protrusions,and this inhibition was not dose-dependent.Then,explore the mechanism of Bisphenol A neurotoxicity and epigenetics.Western blot was used to detect the level of acetylation at the 9th position of histone H3 lysine(AcH3K9),and it was found that Bisphenol A exposure significantly reduced the protein level of Ac-H3K9.Therefore,real-time fluorescence quantitative PCR(q PCR)was used to detect the changes of various histone deacetylases(HDACs).The experiment showed that the gene levels of HDAC1,HDAC2,and HDAC3 increased significantly after the exposure of Bisphenol A.The increasing effect of histone deacetylases 2(HDAC2)is most obvious.Then use Western Blot and immunocytochemistry to verify the changes of HDAC2.Experiments showed that the level of HDAC2 increased significantly after Bisphenol A exposure.2.The role of HDAC2 in Bisphenol A-induced neurotoxicity was investigated on cells.PC12 cells were cultured,Bisphenol A was exposed and Trichostatin A(TSA,a broad-spectrum inhibitor of HDACs)was added or sh HDAC2 plasmid was transfected to inhibit HDAC2 levels,and Ac-H3K9 levels were detected by Western Blot.Experiments show that inhibiting HDAC2 expression can significantly increase the level of Ac-H3K9 after Bisphenol A exposure.Then observe the effect of inhibiting HDAC2 on PC12 cell protrusion after Bisphenol A exposure.The results show that inhibiting HDAC2 can significantly rescue the inhibitory effect of Bisphenol A on the growth of cell processes.3.Animals explored the regulatory role of HDAC2 in bisphenol A-induced neurotoxicity.C57 mice were exposed to Bisphenol A(1 mg/kg/day)by drinking water from pregnancy until 42 days after the pups were born.The pups were injected with sh HDAC2 virus stereotactically to knock down HDAC2 levels.One month after virus expression,frozen section immunofluorescence was used to detect virus expression.Then the hippocampus tissue was extracted and the levels Ac-H3K9 were detected by Western Blot.The results showed that Ac-H3K9 levels in the hippocampus of mice decreased significantly after exposure to Bisphenol A,and knocking down HDAC2 could significantly save the abnormal changes in Ac-H3K9 levels.Next,the Y maze,the Morris water maze was used to detect the effect of Bisphenol A exposure on learning and memory.The results show that Bisphenol A exposure can impair the learning and memory ability of mice,and sh HDAC2 injection to knock down the level of HDAC2 can significantly save learning and memory ability.Then,the density of dendritic spines in the CA1 and DG regions of the hippocampus was observed with Golgi staining.The results showed that Bisphenol A exposure can significantly reduce dendritic spine density in hippocampal CA1 and DG regions,while knocking down HDAC2 level can significantly save dendritic spine density.4.To explore the regulation of ?-catenin by HDAC2 in Bisphenol A-induced neurotoxicity.First,the effect of Bisphenol A exposure on ?-catenin levels and the inhibition of HDAC2 on ?-catenin levels were detected by Western Blot on PC12 cells,and the relationship between HDAC2 and ?-catenin was also detected by immunofluorescence.The results showed that Bisphenol A exposure suppressed the expression of ?-catenin,and the inhibition of HDAC2 level could save ?-catenin levels.Then the hippocampus tissues of the mice were extracted,and the effect of HDAC2 injection on the level of ?-catenin was detected by Western Blot.The results showed that the injection of virus inhibiting HDAC2 can also save ?-catenin levels.Both in vivo and in vitro studies have shown that HDAC2 plays an important role in Bisphenol A-induced neurotoxicity and provides a potential molecular target for preventing and treating Bisphenol A neurotoxicity.