Project description:Progressive aging is associated with changes in sympathetic nervous system (SNS) regulation, suggesting an effect of advancing age on the functionality of central sympathetic premotor neurons. The rostral ventral lateral medulla (RVLM) contains sympathetic premotor neurons and plays a key role in SNS regulation, and it is plausible to speculate that age-related changes in the molecular mechanisms in the RVLM may contribute to alterations in SNS regulation. The present study tested the hypothesis that aging is associated with altered gene expression in the RVLM with emphasis on immune system associated gene transcripts. RVLM tissue punches from young, middle-aged, and aged F344 rats were analyzed using Agilent’s whole rat genome microarray. The RVLM gene expression profile varied with age and an association between chronological age and specific RVLM gene expression patterns was observed (p<0.05, FDR<0.3). Functional analysis of RVLM microarray data via gene ontology profiling and pathway analysis has identified up-regulation of genes associated with immune- and stress- related responses, and down-regulation of genes associated with lipid biosynthesis and neurotransmission in aged compared with middle-aged and young rats. Differentially expressed genes associated with complement system and microglial cells were further validated by quantitative PCR with separate RVLM samples (p<0.05, FDR<0.1). The present results are the first to demonstrate age-related changes in the RVLM molecular mechanisms, modifications that may provide the molecular backdrop for understanding immune-associated changes in SNS regulation.
Project description:We used RNA sequencing to screen differentially expressed genes (DEGs) in the rostral ventral medulla (RVM) and thalamus of rats during persistent orofacial pain to explore the mechanism of chronic orofacial pain.
Project description:The 5HT system is organized into rostral and caudal populations with discrete anatomical locations and opposite axonal trajectories in the developing hindbrain. 5HT neuron cell bodies in the rostral subdivision migrate to the midbrain and pons and extend ascending projections throughout the forebrain. 5HT cell bodies in the caudal subdivision migrate to the ventral medulla and caudal half of the pons and provide descending projections to the brainstem and spinal cord.
Project description:The 5HT system is organized into rostral and caudal populations with discrete anatomical locations and opposite axonal trajectories in the developing hindbrain. 5HT neuron cell bodies in the rostral subdivision migrate to the midbrain and pons and extend ascending projections throughout the forebrain. 5HT cell bodies in the caudal subdivision migrate to the ventral medulla and caudal half of the pons and provide descending projections to the brainstem and spinal cord. Experiment Overall Design: We used microarrays to determine genes expressed by both rostral and caudal 5HT neurons as well as genes that are differentially expressed between rostral and caudal 5HT neurons at E12.5 when axon pathfinding and cell migration are underway. E12.5 neural tubes were isolated from ePet-EYFP embryos and dissected into a rostral domain (mesecephalic flexure to pontine flexure) and a caudal domain (pontine flexure to spinal cord). After cell dissociation (details under growth protocol), cells were subjected to fluorescent activated cell sorting (FACS) to obtain 4 cell populations. R+ = rostral ePetEYFP positive 5HT neurons; R- = YFP negative non-serotonergic cells in the rostral neural tube; C+ = caudal ePetEYFP positive 5HT neurons; C- = YFP negative non-serotonergic cells in the caudal neural tube. 200,000 cells for each of the 4 cell types (R+, R-, C+, C-) were collected for RNA extraction and hybridization to Affymetrix Mouse 430 2.0 arrays.
Project description:This study was performed to investigate the effect of aging and high fat diet on gut microbiota in F344 rats by the pyrosequencing method.
Project description:This study investigated the epigenetic mark of DNA methylation in the medial prefrontal cortex (mPFC) as a function of age and cognition. Young and aged F344 rats were characterized in a cognitive flexibility task, set shifting, and whole-genome bisulfite sequencing was performed in an Illumina system. The results indicate that differential methylation was linked to the expression of genes within functional categories which may mediate impaired cognition in aging. Differences in aging included hypermethylation of genes linked to synaptic function and GTPase activity. Further, age-related cognitive flexibility impairment was correlated to hypermethylation of synaptic, postsynaptic density and ion channel activity genes.
