Changes in Hemodynamic Response Function Resulting From Chronic Alcohol Consumption.
Ontology highlight
ABSTRACT: Background
Functional MRI (fMRI) task-related analyses rely on an estimate of the brain's hemodynamic response function (HRF) to model the brain's response to events. Although changes in the HRF have been found after acute alcohol administration, the effects of heavy chronic alcohol consumption on the HRF have not been explored, and the potential benefits or pitfalls of estimating each individual's HRF on fMRI analyses of chronic alcohol use disorder (AUD) are not known.Methods
Participants with AUD and controls (CTL) received structural, functional, and vascular scans. During fMRI, participants were cued to tap their fingers, and averaged responses were extracted from the motor cortex. Curve fitting on these HRFs modeled them as a difference between 2 gamma distributions, and the temporal occurrence of the main peak and undershoot of the HRF was computed from the mean of the first and second gamma distributions, respectively.Results
ANOVA and regression analyses found that the timing of the HRF undershoot increased significantly as a function of total lifetime drinking. Although gray matter volume in the motor cortex decreased with lifetime drinking, this was not sufficient to explain undershoot timing shifts, and vascular factors measured in the motor cortex did not differ among groups. Comparison of random-effects analyses using custom-fitted and canonical HRFs for CTL and AUD groups showed better results throughout the brain for custom-fitted versus canonical HRFs for CTL subjects. For AUD subjects, the same was true except for the basal ganglia.Conclusions
These findings suggest that excessive alcohol consumption is associated with changes in the HRF undershoot. HRF changes could provide a possible biomarker for the effects of lifetime drinking on brain function. Changes in HRF topography affect fMRI activation measures, and subject-specific HRFs generally improve fMRI activation results.
SUBMITTER: Desmond JE
PROVIDER: S-EPMC7233451 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:Microglia are fundamentally important immune cells within the central nervous system (CNS) that respond to environmental challenges to maintain normal physiological processes. Alterations in steady-state cellular function and over-activation of microglia can facilitate the initiation and progression of neuropathological conditions such as Alzheimer’s disease, Multiple Sclerosis, and Major Depressive Disorder. Alcohol consumption disrupts signaling pathways including both innate and adaptive immune responses that are necessary for CNS homeostasis. Unbiased RNA-Seq profiling was used to identify gene expression changes in isolated microglia in response to recurring bouts of voluntary alcohol drinking behavior. Gene coexpression analysis identified a coordinately regulated group of genes, unique to microglia, that collectively are associated with alcohol consumption. Several genes in this group were involved in toll-like receptor signaling and production of the inflammatory cytokine interferon-gamma. Coordinate expression of these genes is not ascertained from an admixture of CNS cell-types, underscoring the importance of examining isolated cellular populations to reveal systematic gene expression changes arising from mature microglia. We identified a distinctive microglial gene expression signature for neuroimmune responses related to alcohol consumption that provides valuable insight into microglia-specific changes underlying the development of substance abuse, as well as related CNS disorders.
2016-12-10 | GSE91387 | GEO
Project description:Microglia are fundamentally important immune cells within the central nervous system (CNS) that respond to environmental challenges to maintain normal physiological processes. Alterations in steady-state cellular function and over-activation of microglia can facilitate the initiation and progression of neuropathological conditions such as Alzheimer's disease, Multiple Sclerosis, and Major Depressive Disorder. Alcohol consumption disrupts signaling pathways including both innate and adaptive immune responses that are necessary for CNS homeostasis. Coordinate expression of these genes is not ascertained from an admixture of CNS cell-types, underscoring the importance of examining isolated cellular populations to reveal systematic gene expression changes arising from mature microglia. Unbiased RNA-Seq profiling was used to identify gene expression changes in isolated prefrontal cortical microglia in response to recurring bouts of voluntary alcohol drinking behavior. The voluntary ethanol paradigm utilizes long-term consumption ethanol that results in escalated alcohol intake and altered cortical plasticity that is seen in humans. Gene coexpression analysis identified a coordinately regulated group of genes, unique to microglia, that collectively are associated with alcohol consumption. Genes within this group are involved in toll-like receptor signaling and transforming growth factor beta signaling. Network connectivity of this group identified Siglech as a putative hub gene and highlighted the potential importance of proteases in the microglial response to chronic ethanol. In conclusion, we identified a distinctive microglial gene expression signature for neuroimmune responses related to alcohol consumption that provides valuable insight into microglia-specific changes underlying the development of substance abuse, and possibly other CNS disorders.
| S-EPMC5990017 | biostudies-literature
Project description:Chronic alcohol abuse is associated with neurophysiological changes in brain activity; however, these changes are not well localized in humans. Non-human primate models of alcohol abuse enable control over many potential confounding variables associated with human studies. The present study utilized high-resolution magnetoencephalography (MEG) to quantify the effects of chronic EtOH self-administration on resting state (RS) brain function in vervet monkeys.Adolescent male vervet monkeys were trained to self-administer ethanol (n=7) or an isocaloric malto-dextrin solution (n=3). Following training, animals received 12 months of free access to ethanol. Animals then underwent RS magnetoencephalography (MEG) and subsequent power spectral analysis of brain activity at 32 bilateral regions of interest associated with the chronic effects of alcohol use.demonstrate localized changes in brain activity in chronic heavy drinkers, including reduced power in the anterior cingulate cortex, hippocampus, and amygdala as well as increased power in the right medial orbital and parietal areas.The current study is the first demonstration of whole-head MEG acquisition in vervet monkeys. Changes in brain activity were consistent with human electroencephalographic studies; however, MEG was able to extend these findings by localizing the observed changes in power to specific brain regions. These regions are consistent with those previously found to exhibit volume loss following chronic heavy alcohol use. The ability to use MEG to evaluate changes in brain activity following chronic ethanol exposure provides a potentially powerful tool to better understand both the acute and chronic effects of alcohol on brain function.
| S-EPMC5540330 | biostudies-literature
Project description:Functional magnetic resonance imaging (fMRI) has been used to infer age-differences in neural activity from the hemodynamic response function (HRF) that characterizes the blood-oxygen-level-dependent (BOLD) signal over time. BOLD literature in healthy aging lacks consensus in age-related HRF changes, the nature of those changes, and their implications for measurement of age differences in brain function. Between-study discrepancies could be due to small sample sizes, analysis techniques, and/or physiologic mechanisms. We hypothesize that, with large sample sizes and minimal analysis assumptions, age-related changes in HRF parameters could reflect alterations in one or more components of the neural-vascular coupling system. To assess HRF changes in healthy aging, we analyzed the large population-derived dataset from the Cambridge Center for Aging and Neuroscience (CamCAN) study (Shafto et al., 2014). During scanning, 74 younger (18-30 years of age) and 173 older participants (54-74 years of age) viewed two checkerboards to the left and right of a central fixation point, simultaneously heard a binaural tone, and responded via right index finger button-press. To assess differences in the shape of the HRF between younger and older groups, HRFs were estimated using FMRIB's Linear Optimal Basis Sets (FLOBS) to minimize a priori shape assumptions. Group mean HRFs were different between younger and older groups in auditory, visual, and motor cortices. Specifically, we observed increased time-to-peak and decreased peak amplitude in older compared to younger adults in auditory, visual, and motor cortices. Changes in the shape and timing of the HRF in healthy aging, in the absence of performance differences, support our hypothesis of age-related changes in the neural-vascular coupling system beyond neural activity alone. More precise interpretations of HRF age-differences can be formulated once these physiologic factors are disentangled and measured separately.
| S-EPMC6450381 | biostudies-literature
Project description:Alcohol consumption is a risk factor for chronic pancreatitis (CP), but the mechanism in humans remains obscure because prolonged alcohol consumption in most humans and animal models fails to produce alcoholic chronic pancreatitis (ACP). We hypothesize that the process leading to ACP is triggered by a sentinel acute pancreatitis (AP) event; this event causes recruitment of inflammatory cells, which initiates fibrosis driven by the anti-inflammatory response to recurrent AP and/or chronic oxidative stress. The aim was to determine whether chronic alcohol consumption accelerates fibrosis in response to cerulein-induced pancreatitis in the rat. Wistar male rats were pair-fed control (C) or 5% ethanol (E) Lieber-DeCarli liquid diets. Animals were studied without pancreatitis (P0), with cerulein pancreatitis induced once (P1), or with cerulein-induced pancreatitis weekly for 3 weeks (P3). AP markers, inflammation, and fibrosis were measured histologically, by gene expression profiling and protein expression. Macrophage infiltration was reduced in EP0 versus CP0 rats, but the pattern was reversed after AP. Microabscess, severe necrosis, and early calcification were only induced in the EP3 rats. Fibrosis was significantly induced in the EP3 rats versus EP1, CP1, and CP3 by histology, hydroxyproline content, and mRNA expression for collagen alpha1(1) and procollagen alpha2(1). Proinflammatory cytokine mRNAs were up-regulated shortly after induction of AP, while the anti-inflammatory cytokines (interleukin-10 and transforming growth factor-beta) were strongly up-regulated later and in parallel with fibrogenesis, especially in the EP3 rats. Pancreatic fibrosis develops after repeated episodes of AP and is potentiated by alcohol. Expression of fibrosis-associated genes was associated with expression of anti-inflammatory cytokines in alcohol-fed rats.
| S-EPMC1602301 | biostudies-literature
Project description:Alterations in hypothalamic-pituitary-adrenal axis function contribute to many of the adverse behavioral effects of chronic voluntary alcohol drinking, including alcohol dependence and mood disorders; limbic brain structures such as the bed nucleus of the stria terminalis (BNST) may be key sites for these effects. Here, we measured circulating levels of several steroid hormones and performed whole-cell electrophysiological recordings from acutely prepared BNST slices of male rhesus monkeys allowed to self-administer alcohol for 12?months or a control solution. Initial comparisons revealed that BNST neurons in alcohol-drinking monkeys had decreased membrane resistance, increased frequency of spontaneous inhibitory postsynaptic currents (sIPSCs) with no change in spontaneous excitatory postsynaptic currents (sEPSCs). We then used a combined variable cluster analysis and linear mixed model statistical approach to determine whether specific factors including stress and sex hormones, age and measures of alcohol consumption and intoxication are related to these BNST measures. Modeling results showed that specific measures of alcohol consumption and stress-related hormone levels predicted differences in membrane conductance in BNST neurons. Distinct groups of adrenal stress hormones were negatively associated with the frequency of sIPSCs and sEPSCs, and alcohol drinking measures and basal neuronal membrane properties were additional positive predictors of inhibitory, but not excitatory, PSCs. The amplitude of sEPSCs was highly positively correlated with age, independent of other variables. Together, these results suggest that chronic voluntary alcohol consumption strongly influences limbic function in non-human primates, potentially via interactions with or modulation by other physiological variables, including stress steroid hormones and age.
| S-EPMC4732920 | biostudies-literature
Project description:This study investigated changes in gene expression associated with ethanol drinking in adult male P rats under the following conditions for 8 weeks: continuous access (24 hr/day, 7 days/week), multiple scheduled access (three 1-hr sessions during the dark cycle/day, 5 days/week) and ethanol-naive (water). The objective of this study was to investigate changes in gene expression associated with ethanol drinking. Adult male alcohol-preferring (P) rats were given Ethanol in their home-cages under continuous access (CA; 24 hr/day, 7 days/week) or multiple scheduled access (MSA; three 1-hr sessions during the dark cycle/day, 5 days/week) conditions for 8 weeks. A third group was ethanol-naïve (W group). Average ethanol intakes, across the 8 weeks, for the CA and MSA groups were approximately 9.5 and 6.5 g/kg/day, respectively. Fifteen hr after the last ethanol drinking episode, rats were euthanized, the brains rapidly extracted, and the nucleus accumbens (ACB) dissected. RNA was extracted and purified for microarray analysis. The only significant differences, overall, were between the CA and W groups (p < 0.01; Storey false discovery rate = 0.15); there were 374 significant differences in unique named genes between these 2 groups. There were 20 significant Gene Ontology (GO) biological processes categories, which included ‘negative regulation of protein kinase activity’, ‘anti-apoptosis’, and ‘regulation of G-protein-coupled receptor protein signaling pathway’. Ingenuity® analysis indicated a network of transcription factors, involving oncogenes (Fos, Jun, Junb had higher expression levels in the ACB of the CA than W group), suggesting increased neuronal activity in the CA group. There were 13 genes (Hspa5, Stom, Lcn7, Tceb3, Cdc42, Rap1ga1, Ece1, Dhrs3, Plod1, Kif1b, Nmnat1, Srpr, Esam) significantly different between the CA and W groups located within both mouse and rat ethanol QTLs, suggesting that these genes may contribute to ethanol drinking behavior. In conclusion, the robust differences in gene expression found between the CA and W groups, but not observed between the MSA and W groups, may be a result of the higher daily ethanol intakes of the CA group, and/or its initial ethanol withdrawal. Keywords: comparison of gene expression profiles for treated vs. control
2009-09-01 | GSE13524 | GEO
Project description:The objective of this study was to determine the effects of binge-like alcohol drinking on gene expression changes in the nucleus accumbens (ACB) of alcohol-preferring (P) rats. Adult male P rats were given ethanol under multiple scheduled access (MSA; three 1-h dark cycle sessions/day) conditions for 8 weeks. For comparison purposes, a second ethanol drinking group was given continuous/daily alcohol access (CA; 24h/day). A third group was ethanol-naïve (W group). Average ethanol intakes for the CA and MSA groups were approximately 9.5 and 6.5 g/kg/day, respectively. Fifteen hours after the last drinking episode, rats were euthanized, the brains extracted, and the ACB dissected. RNA was extracted and purified for microarray analysis. The only significant differences were between the CA and W groups (p<0.01; Storey false discovery rate=0.15); there were 374 differences in named genes between these 2 groups. There were 20 significant Gene Ontology (GO) categories, which included negative regulation of protein kinase activity, anti-apoptosis, and regulation of G-protein coupled receptor signaling. Ingenuity analysis indicated a network of transcription factors, involving oncogenes (Fos, Jun, Junb had higher expression in the ACB of the CA group), suggesting increased neuronal activity. There were 43 genes located within rat QTLs for alcohol consumption and preference; 4 of these genes (Tgfa, Hspa5, Mtus1 and Creb3l2) are involved in anti-apoptosis and increased transcription, suggesting that they may be contributing to cellular protection and maintaining high alcohol intakes. Overall, these findings suggest that chronic CA drinking results in genomic changes that can be observed during the early acute phase of ethanol withdrawal. Conversely, chronic MSA drinking, with its associated protracted withdrawal periods, results in genomic changes that may be masked by tight regulation of these genes following repeated experiences of ethanol withdrawal.
| S-EPMC2771758 | biostudies-literature
Project description:BackgroundRoutine alcohol screening scores are increasingly available in electronic health records (EHRs). Changes in such scores could be useful for monitoring response to brief intervention or treatment of alcohol use disorder. However, it is unclear whether changes in clinically-documented AUDIT-C alcohol screening scores reflect true changes in drinking. This study evaluated associations between changes in EHR AUDIT-C scores and changes in high density lipoprotein cholesterol (HDL), a laboratory test that reflects average alcohol consumption.MethodsNational U.S. Veterans Affairs EHR data (2004-2007) were used to identify patients screened with the AUDIT-C (0-12 points), on two occasions at least a year apart, who had HDL measured in the year after each screen. First differencing linear regression estimated associations between changes in AUDIT-C score (-12 to 12 points; modeled categorically to allow for non-linear associations) and subsequent changes in HDL (mg/dL), adjusting for baseline HDL. Additional analyses evaluated whether associations between changes in AUDIT-C and changes in HDL were modified by baseline AUDIT-C.ResultsAmong 316,712 patients, increases-but not decreases-in AUDIT-C scores were associated with commensurate changes in HDL. However, a significant interaction was observed with baseline AUDIT-C score (p < 0.00001), which revealed that decreases in AUDIT-C scores were also associated with commensurate decreases in HDL (p-values<0.05) except among the 1.5% of patients with the highest baseline AUDIT-C scores (10-12).ConclusionsFindings suggest that changes in EHR AUDIT-C scores reflect changes in drinking. These results support the use of clinically-documented alcohol screening scores for monitoring patients' alcohol use over time.
| S-EPMC7001877 | biostudies-literature
Project description:AIMS:Within-country temporal changes in alcohol consumption in the United States, Finland and Norway were examined to assess (i) whether a change in mean alcohol consumption is accompanied by a change in the prevalence of heavy drinkers, (ii) whether this mean change reflects a collective displacement in the whole distribution of consumption and (iii) whether collective displacement is found for both an upward and a downward shift in mean consumption. METHODS:We applied repeated cross-sectional survey data on distribution measures for estimated annual alcohol consumption from national population sample surveys covering 30-40-year periods in two countries with increasing trends in mean consumption (Finland and Norway) and one country with decreasing trends (the United States). RESULTS:There was a strong positive association (P?<?0.001) between changes in mean consumption and changes in the prevalence of heavy drinkers in all three countries. Moreover, a change in mean consumption was accompanied by a consumption change in the same direction in all consumer categories in all three countries, i.e. a collective displacement. The regression coefficients were approximately 1. CONCLUSIONS:Drinkers at all levels of consumption appear to move in concert, both up and down the consumption scale, in Finland, Norway and the United States, as predicted by Skog's theory of the collectivity of drinking cultures.
| S-EPMC4127118 | biostudies-literature