Biology subjects

Salisbury, R.

Publications and source records attributed to Salisbury, R..

3 recordsLinked to original sources

bioRxiv2023

Uncovering circadian rhythm disruptions of synaptic proteome signaling in prefrontal cortex and nucleus accumbens associated with opioid use disorder

Opioid craving and relapse vulnerability is associated with severe and persistent sleep and circadian rhythm disruptions. Understanding the neurobiological underpinnings of circadian rhythms and opioid use disorder (OUD) may prove valuable for developing new treatments for opioid addiction. Previous work indicated molecular rhythm disruptions in the human brain associated with OUD, highlighting synaptic alterations in the dorsolateral prefrontal cortex (DLPFC) and nucleus accumbens (NAc)--key brain regions involved in cognition and reward, and heavily implicated in the pathophysiology of OUD. To provide further insights into the synaptic alterations in OUD, we used mass-spectrometry based proteomics to deeply profile protein expression alterations in bulk tissue and synaptosome preparations from DLPFC and NAc of unaffected and OUD subjects. We identified 55 differentially expressed (DE) proteins in DLPFC homogenates, and 44 DE proteins in NAc homogenates, between unaffected and OUD subjects. In synaptosomes, we identified 161 and 56 DE proteins in DLPFC and NAc, respectively, of OUD subjects. By comparing homogenate and synaptosome protein expression, we identified proteins enriched specifically in synapses that were significantly altered in both DLPFC and NAc of OUD subjects. Across brain regions, synaptic protein alterations in OUD subjects were primarily identified in glutamate, GABA, and circadian rhythm signaling. Using time-of-death (TOD) analyses, where the TOD of each subject is used as a time-point across a 24- hour cycle, we were able to map circadian-related changes associated with OUD in synaptic proteomes related to vesicle-mediated transport and membrane trafficking in the NAc and platelet derived growth factor receptor beta signaling in DLPFC. Collectively, our findings lend further support for molecular rhythm disruptions in synaptic signaling in the human brain as a key factor in opioid addiction.

neuroscience↗

bioRxiv2022

Dynamic proteomic and phosphoproteomic atlas of corticostriatal axon neurodevelopment

Mammalian axonal development begins in embryonic stages and continues postnatally. After birth, axonal proteomic landscape changes rapidly, coordinated by transcription, protein turnover, and post-translational modifications. Comprehensive profiling of axonal proteomes across neurodevelopment is limited, with most studies lacking cell-type and neural circuit specificity, resulting in substantial information loss. We create a Cre-dependent APEX2 reporter mouse line and map cell-type specific proteome of corticostriatal projections across postnatal development. We synthesize analysis frameworks to define temporal patterns of axonal proteome and phosphoproteome, identifying co-regulated proteins and phosphorylations associated with genetic risk for human brain disorders. We discover proline-directed kinases as major developmental regulators. APEX2 transgenic reporter proximity labeling offers flexible strategies for subcellular proteomics with cell type specificity in early neurodevelopment, a critical period for neuropsychiatric disease.

neuroscience↗

bioRxiv2019

Synaptic Proteome Alterations in the Primary Auditory Cortex of Schizophrenia

ImportanceFindings from unbiased genetic studies have consistently implicated synaptic protein networks in Schizophrenia (Sz), but the molecular pathology at these networks and their potential contribution to the synaptic and circuit deficits thought to underlie disease symptoms remain unknown.\n\nObjectiveTo determine if protein levels are altered within synapses from primary auditory cortex (A1) of subjects with Sz; and if so, are these differences restricted to the synapse or present throughout the grey matter?\n\nDesignA paired case-control design was utilized for this study. Biochemical fractional - targeted Mass Spectrometry (MS) was used to measure the levels of >350 proteins in A1 grey matter homogenate and synaptosome preparations, respectively. All experimenters were blinded to diagnosis at every stage of sample preparation, MS analysis, and raw data processing. The effects of postmortem interval (PMI) and antipsychotic drug treatment on protein levels were assessed in mouse and monkey models, respectively.\n\nSettingAll cases were recruited from a single site, The Allegheny County Office of the Medical Examiner, and all tissues were processed at the University of Pittsburgh.\n\nParticipantsBrain specimens from all subjects were obtained during autopsies conducted at the Allegheny County Office of the Medical Examiner after receiving consent from the next-of-kin. An independent panel of experienced clinicians made consensus Diagnostic and Statistical Manual of Mental Disorders Fourth Edition diagnoses. Unaffected comparison subjects underwent identical assessments and were determined to be free of lifetime psychiatric illness. Each Sz subject was matched by sex, and as closely as possible for age and PMI, with one unaffected comparison subject.\n\nMain Outcomes and MeasuresPrimary measures were homogenate and synaptosome protein levels and their co-regulation network features. Prior to data collection we hypothesized: 1. That levels of canonical postsynaptic proteins in A1 synaptosome preparations would differ between Sz and control subjects; and 2. That these differences would not be explained by changes in total A1 homogenate protein levels.\n\nResultsMean subject age was 48 years for both groups with a range of 17-83; each group included 35 males and 13 females; mean PMI was 17.7 hours in controls and 17.9 in Sz. We observed robust alterations (q < 0.05) in synaptosome levels of canonical mitochondrial and postsynaptic proteins that were highly co-regulated and not readily explained by postmortem interval, antipsychotic drug treatment, synaptosome yield, or underlying alterations in homogenate protein levels.\n\nConclusions and RelevanceOur findings indicate a robust and highly coordinated rearrangement of the synaptic proteome likely driven by aberrant synaptic, not cell-wide, proteostasis. In line with unbiased genetic findings, our results identified alterations in synaptic levels of postsynaptic proteins, providing a road map to identify the specific cells and circuits that are impaired in Sz A1.

neuroscience↗