Alcohol Dependence in Rats Is Associated with Global Changes in Gene Expression in the Central Amygdala.

Alcohol dependence is associated with adverse consequences of alcohol (ethanol) use and is evident in most severe cases of alcohol use disorder (AUD). The central nucleus of the amygdala (CeA) plays a critical role in the development of alcohol dependence and escalation of alcohol consumption in dependent subjects. Molecular mechanisms underlying the CeA-driven behavioral changes are not well understood. Here, we examined the effects of alcohol on global gene expression in the CeA using a chronic intermittent ethanol (CIE) vapor model in rats and RNA sequencing (RNA-Seq). The CIE procedure resulted in robust changes in CeA gene expression during intoxication, as the number of differentially expressed genes (DEGs) was significantly greater than those expected by chance. Over-representation analysis of cell types, functional groups and molecular pathways revealed biological categories potentially important for the development of alcohol dependence in our model. Genes specific for astrocytes, myelinating oligodendrocytes, and endothelial cells were over-represented in the DEG category, suggesting that these cell types were particularly affected by the CIE procedure. The majority of the over-represented functional groups and molecular pathways were directly related to the functions of glial and endothelial cells, including extracellular matrix (ECM) organization, myelination, and the regulation of innate immune response. A coordinated regulation of several ECM metalloproteinases (e.g., Mmp2; Mmp14), their substrates (e.g., multiple collagen genes and myelin basic protein; Mbp), and a metalloproteinase inhibitor, Reck, suggests a specific mechanism for ECM re-organization in response to chronic alcohol, which may modulate neuronal activity and result in behavioral changes, such as an escalation of alcohol drinking. Our results highlight the importance of glial and endothelial cells in the effects of chronic alcohol exposure on the CeA, and demonstrate further insight into the molecular mechanisms of alcohol dependence in rats. These molecular targets may be used in future studies to develop therapeutics to treat AUD.

Matrix-matched standards in the liquid chromatography-mass spectrometry determination of neonicotinoids in soil and sediment.

The use of matrix-matched standards with a solid-liquid extraction and salting out without the addition of further cleanup steps or costly cleanup procedures associated with the quick, easy, cheap, effective, robust, and safe (QuEChERS) method was evaluated to address variations in ionization efficiency in the LC-MS/MS determination of neonicotinoid pesticides in complex environmental samples. Limits of detection (1.4-3.4 ng/g) and limits of quantitation (4.6-11.3 ng/g) for various neonicotinoid analogs were comparable to previously reported QuEChERS extraction methods. Mean recovery of standard neonicotinoid samples spiked with 10 ng/g was found to be 78.0-100.5%, while samples spiked with 100 ng/g were found to be 55.1-99.9%. Recovery of analytes was matrix dependent; the highest recovery was from sediment (86.2-100.5%) followed by laboratory sand (70.9-81.7%) and agricultural soil (55.5-102.6%), respectively. Optimization of this methodology resulted in the reduction of procedure time and cost, and can aid in environmental monitoring efforts of common neonicotinoid pesticides in soils and sediments.