Neurotoxicity of prenatal alcohol exposure on medullary pre-B?tzinger complex neurons in neonatal rats

Prenatal alcohol exposure disrupts the development of normal fetal respiratory function, but whether it perturbs respiratory rhythmical discharge activity is unclear. Furthermore, it is unknown whether the 5-hydroxytryptamine 2A receptor（5-HT2AR） is involved in the effects of prenatal alcohol exposure. In the present study, pregnant female rats received drinking water containing alcohol at concentrations of 0%, 1%, 2%, 4%, 8% or 10%（v/v） throughout the gestation period. Slices of the medulla from 2-day-old neonatal rats were obtained to record respiratory rhythmical discharge activity. 5-HT2 AR protein and m RNA levels in the pre-B？tzinger complex of the respiratory center were measured by western blot analysis and quantitative RT-PCR, respectively. Compared with the 0% alcohol group, respiratory rhythmical discharge activity in medullary slices in the 4%, 8% and 10% alcohol groups was decreased, and the reduction was greatest in the 8% alcohol group. Respiratory rhythmical discharge activity in the 10% alcohol group was irregular. Thus, 8% was the most effective alcohol concentration at attenuating respiratory rhythmical discharge activity. These findings suggest that prenatal alcohol exposure attenuates respiratory rhythmical discharge activity in neonatal rats by downregulating 5-HT2 AR protein and m RNA levels.

AB049.Astrogliosis in the monkey retina in response to moderate fetal alcohol exposure

Background:Exposure to ethanol in utero leads to several brain development disorders including retinal abnormalities whose underlying cellular pathogenesis remains elusive.We have previously reported changes in electroretinogram recordings in moderate fetal alcohol exposure(MFAE)vervet monkeys.The goal of this study is to characterize the anatomical effects of moderate MFAE during the third trimester in the vervet monkey retina.Methods:Using immunohistochemistry and Western blots,we analyzed changes in the expression of cell-type specific proteins that may occur in the MFAE retina compared to the normal retina.We also compared the basic retinal anatomy across groups by examining retinal layering and thickness.Results:Our main result indicates that GFAP(a potent marker of astrocytes)immunoreactivity was increased in the MFAE retina indicating strong astrogliosis.There was no obvious change in the overall anatomy in the MFAE retina and no significant differences in the mean thickness of each retinal layer.Furthermore,no significant changes in the morphology of the photoreceptors,horizontal cells,bipolar cells,and amacrines cells was observed.Conclusions:These data indicate that astrogliosis is a consequence of prenatal alcohol exposure and might explain the reported changes in the electroretinographic responses.

Adolescent alcohol exposure changes RNA modifications in adult brain by mass spectrometry-based comprehensive profiling analysis

Alcohol consumption is one of the leading causes of death worldwide.Adolescence is a critical period of structural and functional maturation of the brain.Adolescent alcohol use can alter epigenetic modifications.However,little is known on the long-term effects of alcohol consumption during adolescence on RNA epigenetic modifications in brain.Herein,we systematically explored the long-term effects of alcohol exposure during adolescence on small RNA modifications in adult rat brain tissues by comprehensive liquid chromatography-electrospray ionization-tandem mass spectrometry(LC-ESI-MS/MS)analysis.We totally detected 26 modifications in small RNA of brain tissues.Notably,we observed most of these modifications were decreased in brain tissues.These results suggest that alcohol exposure during adolescence may impose a long-lasting impact on RNA modifications in brain tissues.This is the first report that alcohol use during adolescence can alter RNA modifications in adult brain.Collectively,this study suggests a long-term adverse effects of alcohol consumption on brain from RNA epigenetics angle by comprehensive mass spectrometry analysis.

Adolescent alcohol exposure alters DNA and RNA modifications in peripheral blood by liquid chromatography-tandem mass spectrometry analysis

Alcohol consumption is a critical risk factor contributing to a verity of human diseases. The incidence of alcohol use disorder increases across adolescence in recent years. Accumulating line of evidence suggests that alcohol-induced changes of DNA cytosine methylation(5-methyl-2-deoxycytidine, 5 m C) in genomes play an important role in the development of diseases. However, systemic investigation of the effects of adolescent alcohol exposure on DNA and RNA modifications is still lacked. Especially, there hasn’t been any report to study the effects of alcohol exposure on RNA modifications. Similar to DNA modifications,RNA modifications recently have been identified to function as new regulators in modulating numbers of biological processes. In the current study, we systematically investigated the effects of alcohol exposure on both DNA and RNA modifications in peripheral blood of adolescent rats by liquid chromatographyelectrospray ionization-tandem mass spectrometry(LC-ESI-MS/MS) analysis. The developed LC-ESI-MS/MS method enabled the sensitive and accurate determination of 2 DNA modifications and 12 RNA modifications. As for the alcohol exposure experiments, the adolescent rats were intraperitoneally injected with ethanol with an interval of one day for a total 14 days. The quantification results by LC-ESI-MS/MS analysis showed that adolescent alcohol exposure could alter both DNA and RNA modifications in peripheral blood. Specifically, we observed an overall decreased trend of RNA modifications. The discovery of the significant alteration of the levels of DNA and RNA modifications under alcohol exposure indicates that alcohol consumption may increase the risk of the incidence and development of diseases through dysregulating DNA and RNA modifications.

Ceramide is involved in alcohol-induced neural proliferation

Prenatal alcohol exposure, especially during early pregnancy, can lead to fetal alcohol syndrome. The pharmacological and toxicological mechanisms of ethanol are related to the effects of ceramide In this study, we established an alcohol exposure model in wild-type mice and in knockout mice for the key enzyme involved in ceramide metabolism, sphingomyelin synthase 2. This model received daily intragastric administration of 25% ethanol, and pups were used at postnatal days 0, 7, 14, 30 for experiments. Serology and immunofluorescence staining found that ethanol exposure dose-dependently reduced blood sphingomyelin levels in two genotypes of pups, and increased neural cell proliferation and the number of new neurons in the hippocampal dentate gyrus. Western blot analysis showed that the relative expression level of protein kinase C e increased in two genotypes of pups after ethanol exposure. Compared with witd-type pups, the expression level of the important activator protein of the ceramide/ceramide-l-phosphate pathway, protein kinase C a, was reduced in the hippocampus of sphingomyelin synthase 2 knockouts. Our findings illustrate that ceramide is involved in alcohol-induced neural proliferation in the hippocampal dentate gyrus of pups after prenatal ethanol exposure, and the mechanism may be associated with increased ex- pression of protein kinase C a activating the ceramide/ceramide-l-phosphate pathway.

Glial plasticity after hexahydrobenzene exposure

The organic solvents are not only utilized in industrial processes,but also as drugs of abuse.In fact,solvent consumption represents the fourth option for drug users just after alcohol,tobacco and marijuana.In humans,intentional inhalation of volatile drugs impairs the function of central nervous system,