Project description:Methamphetamine use disorder (MUD) is a chronic, relapsing disease that is characterized by repeated drug use despite negative consequences for which there are currently no FDA approved cessation therapeutics. Repeated methamphetamine (METH) use induces long-term gene expression changes in brain regions associated with reward processing and drug-seeking behavior, and recent evidence suggests that methamphetamine-induced neuroinflammation may also shape behavioral and molecular responses to the drug. Microglia, the resident immune cells in the brain, are principal drivers of neuroinflammatory responses and contribute to the pathophysiology of substance use disorders. Here, we investigated transcriptional and morphological changes in striatal microglia in response to methamphetamine-taking and during methamphetamine abstinence, as well as their functional contribution to drug-taking behavior. We show that methamphetamine self-administration induces transcriptional changes related to protein folding, mRNA processing, immune signaling, and neurotransmission in striatal microglia. Importantly, many of these transcriptional changes persist through abstinence, a finding supported by morphological analysis. Functionally, we report that microglial ablation increases methamphetamine-taking, possibly involving neuroimmune and neurotransmitter regulation. In contrast, microglial depletion did not alter methamphetamine-seeking behavior following 21 days of abstinence, highlighting the complexity of drug-seeking behaviors. Taken together, these results suggest that methamphetamine induces both short and long-term changes in striatal microglia that contribute to altered drug-taking behavior and may be leveraged for preclinical development of methamphetamine cessation therapeutics.
Project description:Methamphetamine is a widely abused, highly addictive drug. Regulation of synaptic proteins within the brain’s reward pathway modulates addiction behaviours, the progression of drug addiction and long-term changes in brain structure and function that result from drug use. Therefore, using large scale proteomics studies we aim to identify global protein expression changes within the dorsal striatum, a key brain region involved in the modulation of addiction. We performed LC-MS/MS analyses on rat striatal synaptosomes following 30 days of methamphetamine self-administration (2 hours/day) and 14 days abstinence. We identified a total of 84 differentially-expressed proteins with known roles in neuroprotection, neuroplasticity, cell cytoskeleton, energy regulation and synaptic vesicles. We identify significant expression changes in stress-induced phosphoprotein and protein Tppp, which have not previously been associated with addiction. In addition, we confirm the role of amphiphysin and phosphatidylethanolamine binding protein in addiction. This approach has provided new insight into the effects of methamphetamine self-administration on synaptic protein expression in a key brain region associated with addiction, showing a large set of differentially-expressed proteins that persist into abstinence.
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
