Project description:Sevoflurane is the most commonly used general anesthetic in pediatric surgery, but it has the potential to be neurotoxic. Previous research found that long-term or multiple sevoflurane exposures could cause cognitive deficits in newborn mice but not adult mice, whereas short-term or single inhalations had little effect on cognitive function at both ages. The mechanisms behind these effects, however, are unclear. In the current study, 6- and 60-day-old C57bl mice in the sevoflurane groups were given 3% sevoflurane plus 60% oxygen for three consecutive days, each lasting 2 hours, while those in the control group only got 60% oxygen. The cortex tissues were harvested on the 8th or 62nd day. The tandem mass tags (TMT)pro-based quantitative proteomics combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysi were applied to analyze the influences of multiple sevoflurane anesthesia on the cerebral cortex in mice with various ages. A total of 6247 proteins were measured using the combined quantitative proteomics methods of TMTpro-labeled and LC-MS/MS, 443 of which were associated to the age-dependent neurotoxic mechanism of repeated sevoflurane anesthesia. Our findings would help to further the mechanistic study of age-dependent anesthetic neurotoxicity and contribute to seek for effective protection in the developing brain under general anesthesia.
Project description:Repeated exposures to insulin-induced hypoglycemia in diabetic patients progressively impair the counter-regulatory response (CRR) that restores normoglycemia. This defect is characterized by reduced secretion of glucagon and other counter-regulatory hormones. Evidence indicates that glucose responsive neurons located in the hypothalamus, orchestrate the CRR. Here, we aimed at identifying the changes in hypothalamic gene and protein expression that underlie impaired CRR. High fat diet fed and low dose streptozocin-treated C57BL6N mice were exposed to one (acute hypoglycemia, AH) or multiple (recurrent hypoglycemia, RH) insulin-induced hypoglycemic episodes. Single nuclei RNA sequencing (snRNAseq) data were obtained from the hypothalamus and cortex of AH and RH mice. Proteomic data were also obtained from hypothalamic synaptosomal fractions. The present study shows that repeated moderate hypoglycemia in diabetic mice lead, in the hypothalamus, to multiple cellular physiology changes, affecting all cell types and their interactions, which show striking features of neurodegenerative diseases. It also shows that repeated hypoglycemic episodes affect very differently the hypothalamus and the cortex.
Project description:Studies on aging have largely included one or two OMICS layers, which may not necessarily reflect the signatures of other layers. Moreover, most aging studies have often compared very young (4-5 wks) mice with old (24 months) mice which does not reflect the aging transition after the attainment of adulthood. Therefore, we aimed to study and compared muti-OMICS aging signatures across key metabolic tissues of mature adults (6 months) and old (24 months) C57BL/6J mice (the most commonly used mouse strain). Here we compared the differentially regulated genes and enriched pathways for transcriptome, proteome and epigenome (H3K27ac, H3K4me3, H3K27me3, DNA methylation) across liver, heart, and quadriceps muscle. The major aging associated pathways cross multiple layers and tissues are decreased RNA metabolism, transcription, and translation at transcript and protein levels however increased potential of transcription at DNA methylation and H3K27ac levels.