Hippocampal PACAP signaling activation triggers a rapid antidepressant response.

BACKGROUND: The development of ketamine-like rapid antidepressants holds promise for enhancing the therapeutic efficacy of depression, but the underlying cellular and molecular mechanisms remain unclear. Implicated in depression regulation, the neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP) is investigated here to examine its role in mediating the rapid antidepressant response. METHODS: The onset of antidepressant response was assessed through depression-related behavioral paradigms. The signaling mechanism of PACAP in the hippocampal dentate gyrus (DG) was evaluated by utilizing site-directed gene knockdown, pharmacological interventions, or optogenetic manipulations. Overall, 446 mice were used for behavioral and molecular signaling testing. Mice were divided into control or experimental groups randomly in each experiment, and the experimental manipulations included: chronic paroxetine treatments (4, 9, 14 d) or a single treatment of ketamine; social defeat or lipopolysaccharides-injection induced depression models; different doses of PACAP (0.4, 2, 4 ng/site; microinjected into the hippocampal DG); pharmacological intra-DG interventions (CALM and PACAP6-38); intra-DG viral-mediated PACAP RNAi; and opotogenetics using channelrhodopsins 2 (ChR2) or endoplasmic natronomonas halorhodopsine 3.0 (eNpHR3.0). Behavioral paradigms included novelty suppressed feeding test, tail suspension test, forced swimming test, and sucrose preference test. Western blotting, ELISA, or quantitative real-time PCR (RT-PCR) analysis were used to detect the expressions of proteins/peptides or genes in the hippocampus. RESULTS: Chronic administration of the slow-onset antidepressant paroxetine resulted in an increase in hippocampal PACAP expression, and intra-DG blockade of PACAP attenuated the onset of the antidepressant response. The levels of hippocampal PACAP expression were reduced in both two distinct depression animal models and intra-DG knockdown of PACAP induced depression-like behaviors. Conversely, a single infusion of PACAP into the DG region produced a rapid and sustained antidepressant response in both normal and chronically stressed mice. Optogenetic intra-DG excitation of PACAP-expressing neurons instantly elicited antidepressant responses, while optogenetic inhibition induced depression-like behaviors. The longer optogenetic excitation/inhibition elicited the more sustained antidepressant/depression-like responses. Intra-DG PACAP infusion immediately facilitated the signaling for rapid antidepressant response by inhibiting calcium/calmodulin-dependent protein kinase II (CaMKII)-eukaryotic elongation factor 2 (eEF2) and activating the mammalian target of rapamycin (mTOR). Pre-activation of CaMKII signaling within the DG blunted PACAP-induced rapid antidepressant response as well as eEF2-mTOR-brain-derived neurotrophic factor (BDNF) signaling. Finally, acute ketamine treatment upregulated hippocampal PACAP expression, whereas intra-DG blockade of PACAP signaling attenuated ketamine's rapid antidepressant response. CONCLUSIONS: Activation of hippocampal PACAP signaling induces a rapid antidepressant response through the regulation of CaMKII inhibition-governed eEF2-mTOR-BDNF signaling.

Exploring the interplay between addiction and time perception: A systematic review and meta-analysis.

Prior studies have investigated the immediate impacts of substances on temporal perception, the impact of temporal outlook, and the consequences of modified temporal perception on addictive behaviors. These inquiries have provided valuable perspectives on the intricate associations between addiction and time perception, enriching the groundwork for forthcoming research and therapeutic strategies. This comprehensive review aims to further explore intricate correlation among diverse addictive substances-namely alcohol, cannabis, nicotine, opioids-and non-substance addictions such as internet gaming, elucidating their influence on temporal perception. Adhering to the PICOS method and adhering to PRISMA guidelines, we systematically reviewed and critically evaluated all existing research concerning temporal perception in individuals with substance and non-substance use disorders. Specifically, our analyses involved 31 pertinent articles encompassing six unique groups-alcohol, nicotine, cannabis, stimulants, opioids, and internet-related addictions-sourced from a pool of 551 papers. The findings revealed differences in time perception between addicts and control groups, as indicated by medium to large effect sizes (Hedge's g = 0.8, p < 0.001). However, the nature of these differences-whether they predominantly involve time overestimation or underestimation-is not yet definitively clear. This variability underscores the complexity of the relationship between addiction and temporal perception, paving the way for further research to unravel these intricate dynamics.

Treadmill exercise training inhibits morphine CPP by reversing morphine effects on GABA neurotransmission in D2-MSNs of the accumbens-pallidal pathway in male mice.

Relapse is a major challenge in the treatment of drug addiction, and exercise has been shown to decrease relapse to drug seeking in animal models. However, the neural circuitry mechanisms by which exercise inhibits morphine relapse remain unclear. In this study, we report that 4-week treadmill training prevented morphine conditioned place preference (CPP) expression during abstinence by acting through the nucleus accumbens (NAc)-ventral pallidum (VP) pathway. We found that neuronal excitability was reduced in D2-dopamine receptor-expressing medium spiny neurons (D2-MSNs) following repeated exposure to morphine and forced abstinence. Enhancing the excitability of NAc D2-MSNs via treadmill training decreased the expression of morphine CPP. We also found that the effects of treadmill training were mediated by decreasing enkephalin levels and that restoring opioid modulation of GABA neurotransmission in the VP, which increased neurotransmitter release from NAc D2-MSNs to VP, decreased morphine CPP. Our findings suggest the inhibitory effect of exercise on morphine CPP is mediated by reversing morphine-induced neuroadaptations in the NAc-to-VP pathway.

Altered N-linked glycosylation in depression: A pre-clinical study.

BACKGROUND: Neuroimmune plays an important role in major depressive disorders (MDD). N-linked protein glycosylation (NLG) might contribute to depression by regulating the neuroinflammatory response. As microglia is the main executor of neuroimmune function in the central neural system (CNS), targeting the process of N-linked protein glycosylation of microglia in the mice used for studying depression might potentially offer new avenues for the strategy for MDD. METHODS: The chronic unpredictable mild stress (CUMS) mouse model was established for the whole brain microglia isolating. Then, RNA samples of microglia were extracted for transcriptome sequencing and mRNA analysis. Immunofluorescence (IF) was used to identify the expression level of NLG-related enzyme, B4galt1, in microglia. RESULTS: The data showed that NLG was positively related to depression. Moreover, the NLG-related gene, B4galt1 increased expression in the microglia of CUMS mice. Then, the inhibition of NLG reversed the depressive behavior in CUMS mice. The expression level of B4galt1 in CUMS mice was upregulating following the NLG-inhibitor treatment. Similar results haven't been observed in neurons. Information obtained from these experiments showed increasing expression of B4galt1 in microglia following depressive-like behaviors. CONCLUSIONS: These findings indicate that NLG in microglia is associated with MDD, and suggest that therapeutically targeting NLG might be an effective strategy for depression. LIMITATIONS: How to modulate the B4galt1 or NLG pathways in microglia efficiently and economically request new technologies.

Dynamics of N6-methyladenosine modification during Alzheimer's disease development.

N6-methyladenosine (m6A) modification is a common RNA modification in the central nervous system and has been linked to various neurological disorders, including Alzheimer's disease (AD). However, the dynamic of mRNA m6A modification and m6A enzymes during the development of AD are not well understood. Therefore, this study examined the expression profiles of m6A and its enzymes in the development of AD. The results showed that changes in the expression levels of m6A regulatory factors occur in the early stages of AD, indicating a potential role for m6A modification in the onset of the disease. Additionally, the analysis of mRNA m6A expression profiles using m6A-seq revealed significant differences in m6A modification between AD and control brains. The genes with differential methylation were found to be enriched in GO and KEGG terms related to processes such as inflammation response, immune system processes. And the differently expressed genes (DEGs) are negatively lryassociated with genes involved in microglia hemostasis, but positively associated with genes related to "disease-associated microglia" (DAM) associated genes. These findings suggest that dysregulation of mRNA m6A modification may contribute to the development of AD by affecting the function and gene expression of microglia.

Multiple mediation of the association between childhood emotional abuse and adult obesity by anxiety and bulimia - a sample from bariatric surgery candidates and healthy controls.

Bulimia, which means a person has episodes of eating a very large amount of food (bingeing) during which the person feels a loss of control over their eating, is the most primitive reason for being overweight and obese. The extended literature has indicated that childhood emotional abuse has a close relationship with adverse mood states, bulimia, and obesity. To comprehensively understand the potential links among these factors, we evaluated a multiple mediation model in which anxiety/depression and bulimia were mediators between childhood emotional abuse and body mass index (BMI). A set of self-report questionnaires, including the Childhood Trauma Questionnaire (CTQ), Beck Anxiety Inventory, Beck Depression Inventory (BDI), and Eating Disorder Inventory (EDI), was sent out. Clinical data from 37 obese patients (age: 29.65 ± 5.35, body mass index (BMI): 37.59 ± 6.34) and 37 demographically well-matched healthy people with normal body weight (age: 31.35 ± 10.84, BMI: 22.16 ± 3.69) were included in the investigation. We first performed an independent t-test to compare all scales or subscale scores between the two groups. Then, we conducted Pearson correlation analysis to test every two variables' pairwise correlation. Finally, multiple mediation analysis was performed with BMI as the outcome variable, and childhood emotional abuse as the predictive variable. Pairs of anxiety, bulimia, and depression, bulimia were selected as the mediating variables in different multiple mediation models separately. The results show that the obese group reported higher childhood emotional abuse (t = 2.157, p = 0.034), worse mood state (anxiety: t = 5.466, p < 0.001; depression: t = 2.220, p = 0.030), and higher bulimia (t = 3.400, p = 0.001) than the healthy control group. Positive correlations were found in every pairwise combination of BMI, childhood emotional abuse, anxiety, and bulimia. Multiple mediation analyses indicate that childhood emotional abuse is positively linked to BMI (ß = 1.312, 95% CI = 0.482-2.141). The model using anxiety and bulimia as the multiple mediating variables is attested to play roles in the relationship between childhood emotional abuse and obesity (indirect effect = 0.739, 95% CI = 0.261-1.608, 56.33% of the total effect). These findings confirm that childhood emotional abuse contributes to adulthood obesity through the multiple mediating effects of anxiety and bulimia. The present study adds another potential model to facilitate our understanding of the eating psychopathology of obesity.

The resting-state brain activity signatures for addictive disorders.

BACKGROUND: Addiction is a chronic and relapsing brain disorder. Despite numerous neuroimaging and neurophysiological studies on individuals with substance use disorder (SUD) or behavioral addiction (BEA), currently a clear neural activity signature for the addicted brain is lacking. METHODS: We first performed systemic coordinate-based meta-analysis and partial least-squares regression to identify shared or distinct brain regions across multiple addictive disorders, with abnormal resting-state activity in SUD and BEA based on 46 studies (55 contrasts), including regional homogeneity (ReHo) and low-frequency fluctuation amplitude (ALFF) or fractional ALFF. We then combined Neurosynth, postmortem gene expression, and receptor/transporter distribution data to uncover the potential molecular mechanisms underlying these neural activity signatures. FINDINGS: The overall comparison between addiction cohorts and healthy subjects indicated significantly increased ReHo and ALFF in the right striatum (putamen) and bilateral supplementary motor area, as well as decreased ReHo and ALFF in the bilateral anterior cingulate cortex and ventral medial prefrontal cortex, in the addiction group. On the other hand, neural activity in cingulate cortex, ventral medial prefrontal cortex, and orbitofrontal cortex differed between SUD and BEA subjects. Using molecular analyses, the altered resting activity recapitulated the spatial distribution of dopaminergic, GABAergic, and acetylcholine system in SUD, while this also includes the serotonergic system in BEA. CONCLUSIONS: These results indicate both common and distinctive neural substrates underlying SUD and BEA, which validates and supports targeted neuromodulation against addiction. FUNDING: This work was supported by the National Natural Science Foundation of China and Intramural Research Program of the National Institute on Drug Abuse, National Institutes of Health.

An Electroencephalography Profile of Paroxysmal Kinesigenic Dyskinesia.

Paroxysmal kinesigenic dyskinesia (PKD) is associated with a disturbance of neural circuit and network activities, while its neurophysiological characteristics have not been fully elucidated. This study utilized the high-density electroencephalogram (hd-EEG) signals to detect abnormal brain activity of PKD and provide a neural biomarker for its clinical diagnosis and PKD progression monitoring. The resting hd-EEGs are recorded from two independent datasets and then source-localized for measuring the oscillatory activities and function connectivity (FC) patterns of cortical and subcortical regions. The abnormal elevation of theta oscillation in wildly brain regions represents the most remarkable physiological feature for PKD and these changes returned to healthy control level in remission patients. Another remarkable feature of PKD is the decreased high-gamma FCs in non-remission patients. Subtype analyses report that increased theta oscillations may be related to the emotional factors of PKD, while the decreased high-gamma FCs are related to the motor symptoms. Finally, the authors established connectome-based predictive modelling and successfully identified the remission state in PKD patients in dataset 1 and dataset 2. The findings establish a clinically relevant electroencephalography profile of PKD and indicate that hd-EEG can provide robust neural biomarkers to evaluate the prognosis of PKD.

An electroencephalographic signature predicts craving for methamphetamine.

Craving is central to methamphetamine use disorder (MUD) and both characterizes the disease and predicts relapse. However, there is currently a lack of robust and reliable biomarkers for monitoring craving and diagnosing MUD. Here, we seek to identify a neurobiological signature of craving based on individual-level functional connectivity pattern differences between healthy control and MUD subjects. We train high-density electroencephalography (EEG)-based models using data recorded during the resting state and then calculate imaginary coherence features between the band-limited time series across different brain regions of interest. Our prediction model demonstrates that eyes-open beta functional connectivity networks have significant predictive value for craving at the individual level and can also identify individuals with MUD. These findings advance the neurobiological understanding of craving through an EEG-tailored computational model of the brain connectome. Dissecting neurophysiological features provides a clinical avenue for personalized treatment of MUD.

Advances in neuroimaging studies of alcohol use disorder (AUD).

Alcohol use disorder (AUD) is a worldwide problem and the most common substance use disorder. Chronic alcohol consumption may have negative effects on the body, the mind, the family, and even society. With the progress of current neuroimaging methods, an increasing number of imaging techniques are being used to objectively detect brain impairment induced by alcoholism and serve a vital role in the diagnosis, prognosis, and treatment assessment of AUD. This article organizes and analyzes the research on alcohol dependence concerning the main noninvasive neuroimaging methods, structural magnetic resonance imaging, functional magnetic resonance imaging, and electroencephalography, as well as the most common noninvasive brain stimulation - transcranial magnetic stimulation, and intersperses the article with joint intra- and intergroup studies, providing an outlook on future research directions.

Working memory dysfunction in insomniac adults: a systematic metanalytical review / Disfunção da memória de trabalho em adultos insones: uma revisão sistemática

BACKGROUND: Insomnia is the most commonly occurring sleep disorder: recent reports estimate that 25-30% of adults in the general population occasional instances of experience insomnia, while 10% suffer from disturbances severe enough to meet diagnostic criteria for insomnia. Little is known about the mechanisms, causes, clinical course, and consequences of this condition. Over 30 studies have been published on the matter but only a small proportion has found differences in the working memory of individuals with vs. without insomnia. OBJECTIVE: To summarize evidence regarding the differences in working memory performance between insomniac vs. normal adult sleepers. METHODS: The survey was conducted using an advanced search in the ISI Web of Science and MEDLINE/PubMed with the terms "sleep", "insomnia" and "working memory" as major descriptors; these were crossed with the following keywords: "psychological tests", "neuropsychology" and "performance". RESULTS: A total of 112 articles were identified in the search conducted in PubMed and Web of Science. After the screening, 102 articles unrelated to the proposed theme were excluded. Thus, 10 articles were analyzed by the eligibility and exclusion criteria, and included in this systematic review. CONCLUSION: The information resulting from the analysis of the reviewed articles suggests that mild, but not definitive deficits in cognitive performance might be masked by insignificant disparities in studies comparing insomniac individuals with normal sleepers. This shortcoming can be circumvented by larger and better-characterized samples, together with optimized methodological control of factors which might otherwise result in confounding variations among participants.

INTRODUÇÃO: A insônia é o distúrbio do sono mais comum: relatórios recentes estimam que 25-30% dos adultos sofrem episódios de insônia, enquanto 10% sofrem de distúrbio do sono suficientemente grave para cumprir os critérios de diagnóstico para insônia. Além disso, pouco se sabe sobre os mecanismos, causas, evolução clínica, e consequências desta doença crónica altamente prevalente. Mais de 30 estudos foram publicados sobre o assunto, mas apenas uma pequena proporção encontrou diferenças entre os indivíduos com e sem insônia, por exemplo, na memória de trabalho. OBJETIVO: Examinar as evidências sobre as diferenças entre adultos insones e normais no desempenho da memória de trabalho. MÉTODOS: A pesquisa foi realizada usando uma pesquisa avançada no ISI Web of Science e MEDLINE/PubMed com os termos "sleep", "insônia" e "memória de trabalho" como os principais descritores, que foram cruzados com as seguintes palavras-chave: "testes psicológicos", "neuropsicologia" e "performance". RESULTADOS: Um total de 132 artigos foram identificados na pesquisa realizada no PubMed e Web of Science; 20 duplicações foram excluídas. Após a triagem, 102 artigos foram excluídos, que não estavam relacionadas com o tema proposto. Assim, 10 artigos foram selecionados por critérios de elegibilidade e de exclusão, e incluídos na revisão sistemática. CONCLUSÃO: As descobertas relatadas em nosso estudo sugerem que os deficits leves mas não permanentes de desempenho cognitivo podem ser mascarados por disparidades insignificantes em estudos que comparam indivíduos com insônia com pessoas com sono normal. Tal deficiência pode ser contornada pela análise de amostras maiores e mais bem caracterizadas, em conjunto com o controle metodológico otimizado de fatores que potencialmente podem incorrer em variações entre os participantes.