DRD2 Expression Research Articles

Effect of the LncRNA-LIN-miRNA-9-DRD2 regulatory network on the development of the neuronal system after inhalation of the anesthetic sevoflurane.

Animal studies have shown that exposure of newborns to general anesthesia drugs can lead to neurodegenerative diseases and subsequent decline in learning and memory abilities. The neurotoxicity of general anesthesia drugs can also occur in the fetus. Therefore, in order to investigate the effect of the Long non-coding RNA(LncRNA)-LIN-microRNA(miRNA)-9-Dopamine receptor D2(DRD2) regulatory network on the development of the neuronal system after the inhalation of the anesthetic sevoflurane, RT-qPCR was used to detect the mRNA levels of LncRNA-LIN, miRNA-9, and DRD2. A dual-luciferase reporter system was used to detect the relationship between LncRNA-LIN and miRNA-9, and miRNA-9 and DRD2. Western blotting and immunofluorescence staining was employed to detect the protein levels of DRD2 and cleaved caspase-3. Flow cytometry was carried out to detect the number of apoptotic cells. The escape latency, swimming distance, and platform crossing times were analyzed using the Morris water maze. The results showed that, after treatment with sevoflurane, the mRNA levels of LncRNA-LIN and DRD2, the expression levels of the DRD2 protein, and the number of neuronal levels of DRD2 were significantly decreased, whereas the expression levels of miRNA-9 and the cleaved caspase-3 protein and neuronal apoptosis were significantly increased. miR-9 knockdown revealed that miRNA-9 regulated DRD2 expression and affected the function of mouse neuronal cells. In turn, LncRNA-LIN overexpression indicated that LncRNA-LIN regulated miR-9 and affected the function of mouse neuronal cells. The present results demonstrated that the LncRNA-LIN-miRNA-9-DRD2 regulatory network is involved in the effects of the inhalation anesthetic sevoflurane on neuronal system development.

The Effect of Memantine on the Expression of Dopamine Receptors in the Striatum of Male Rats With Morphine Addiction

Background and Objectives: Studies have indicated that the chronic use of morphine can result in physical and psychological dependence. Morphine dependence is associated with several cellular and molecular alterations in the mesocorticolimbic system, and striatal dopamine signaling is involved in this process. In the present study, we aim to investigate possible alterations in the level of dopamine receptors DRD2 and DRD4 in the striatum of male rats following chronic oral administration of morphine and assess the effect of subcutaneous injection of memantine on morphine-induced effects. Methods: In this experimental study, 16 male Wistar rats were randomly divided into four groups: Control, morphine, memantine, and morphine+memantine. The morphine group received increasing doses of morphine (0.1-0.4 mg/kg) via their drinking water for 21 consecutive days. The memantine groups, after receiving distilled water without morphine for 21 days, received a subcutaneous injection of 5 mg memantine. The morphine memantine group received 5 mg of memantine subcutaneously on day 21 and 30 minutes after the last oral administration of morphine. After collecting striatum tissue, dopamine receptor levels were evaluated by the western blotting method. Results: The chronic use of morphine increased the levels of DRD2 and DRD4 compared to the controls. Memantine administration also increased the level of these receptors compared to the controls. In addition, the expression of DRD2 and DRD4 increased in the morphine+ memantine group compared to the memantine group. Conclusion: Morphine affects the expression of dopamine receptors in the striatum. Treatment with memantine can increases dopamine receptors’ expression.

Synergistic combination of perphenazine and temozolomide suppresses patient-derived glioblastoma tumorspheres.

Glioblastoma (GBM), a primary malignant brain tumor, has a poor prognosis, even with standard treatments such as radiotherapy and chemotherapy. In this study, we explored the anticancer effects of the synergistic combination of perphenazine (PER), a dopamine receptor D2/3 (DRD2/3) antagonist, and temozolomide (TMZ), a standard treatment for GBM, in patient-derived human GBM tumorspheres (TSs). The biological effects of the combination of PER and TMZ in GBM TSs were assessed by measuring cell viability, ATP, stemness, invasiveness, and apoptosis. Changes in protein and mRNA expression were analyzed using western blotting and RNA sequencing. Co-administration of PER and TMZ was evaluated in vivo using a mouse orthotopic xenograft model. The Severance dataset showed that DRD2 and DRD3 expression was higher in tumor tissues than in the tumor-free cortex of patients with GBM. DRD2/3 knockout by CRISPR/Cas9 in patient-derived human GBM TSs inhibited cell growth and ATP production. The combined treatment with PER and TMZ resulted in superior effects on cell viability and ATP assays compared to those in single treatment groups. Flow cytometry, western blotting, and RNA sequencing confirmed elevated apoptosis in GBM TSs following combination treatment. Additionally, the combination of PER and TMZ downregulated the expression of protein and mRNA associated with stemness and invasiveness. In vivo evaluation showed that combining PER and TMZ extended the survival period of the mouse orthotopic xenograft model. The synergistic combination of PER and TMZ has potential as a novel combination treatment strategy for GBM.

Integrating network pharmacology and bioinformatics to explore the mechanism of Xiaojian Zhongtang in treating major depressive disorder: An observational study.

Major depressive disorder (MDD) is a common mental illness. The traditional Chinese medicine compound Xiaojian Zhongtang (XJZT) has a good therapeutic effect on MDD, but the specific mechanism is not clear. The aim of this study is to explore the molecular mechanism of XJZT in the treatment of MDD through network pharmacology and bioinformatics. The traditional Chinese medicine system pharmacology database was used to screen the chemical components and targets of XJZT, while the online Mendelian inheritance in man, DisGeNET, Genecards, and therapeutic target database databases were used to collect MDD targets and identify the intersection targets of XJZT and MDD. A "drugs-components-targets" network was constructed using the Cytoscape platform, and the STRING was used for protein-protein interaction analysis of intersecting targets. Gene Ontology and Kyoto encyclopedia of genes and genomes analysis of intersecting targets was performed using the DAVID database. Obtain serum and brain transcriptome datasets of MDD from the gene expression omnibus database, and perform differentially expressed genes, weighted gene co-expression network analysis, gene set enrichment analysis, and receiver operating characteristic analysis. A total of 127 chemical components and 767 targets were obtained from XJZT, among which quercetin, kaempferol, and maltose are the core chemical components, and 1728 MDD targets were screened out, with 77 intersecting targets between XJZT and MDD. These targets mainly involve AGE-RAGE signaling pathway in diabetic complexes, epidermal growth factor receptor tyrosine kinase inhibitor resistance, and HIF-1 signaling pathway, and these core targets have strong binding activity with core components. In addition, 1166 differentially expressed genes were identified in the MDD serum transcriptome dataset, and weighted gene co-expression network analysis identified the most relevant gene modules (1269 genes), among which RAC-alpha serine/threonine-protein kinase (AKT1), D(4) dopamine receptor (DRD4), and kynurenine 3-monooxygenase (KMO) were target genes for the treatment of MDD with XJZT, these 3 genes are mainly related to the ubiquitin-mediated proteolysis, arachidonic acid (AA) metabolism, and Huntington disease pathways, and the expression of AKT1, DRD4, and KMO was also found in the MDD brain transcriptome dataset, which is significantly correlated with the occurrence of MDD. We have identified 3 key targets for XJZT treatment of MDD, including AKT1, KMO, and DRD4, and they can be regulated by the key components of XJZT, including quercetin, maltose, and kaempferol. This provides valuable insights for the early clinical diagnosis and development of therapeutic drugs for MDD.

Ferroptosis-related gene signature predicts prognosis and immune microenvironment in prostate cancer.

Ferroptosis, an iron-dependent form of programmed cell death, significantly impacts cancer, yet its link to prostate cancer (PCa) prognosis remains underexplored. This study aims to develop and validate a ferroptosis-related gene signature to predict PCa prognosis and immune microenvironment differences, potentially identifying therapeutic targets. RNA-sequencing data of 478 PCa patients and corresponding clinical data were downloaded from The Cancer Genome Atlas (TCGA) database. We investigated the disease-free survival (DFS) rates of the high- and low-risk groups using the Kaplan-Meier method. Functional differences between the high- and low-risk groups were investigated by a gene set enrichment analysis (GSEA), and Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. The link between ferroptosis risk score and immune status was examined using CIBERSORT. The expression levels of core prognostic genes in benign prostatic hyperplasia (BPH) and PCa were verified using quantitative real-time polymerase chain reaction (qRT-PCR), Western blot, and immunohistochemistry (IHC). A novel ferroptosis-related prognostic gene signature was established and tested in the Gene Expression Omnibus (GEO) database based on univariate and multivariate Cox regression analyses. Patients with PCa were classified into high- and low-risk groups based on this ferroptosis signature. Patients in the high-risk group had worse outcomes than those in the low-risk group. The predictive accuracy of the model was demonstrated by a receiver operating characteristic (ROC) analysis. An additional enrichment analysis of TCGA cohort revealed the immune-related pathways were significantly upregulated in the high-risk group, with areas under the curve (AUCs) of 0.85 at 1 year, 0.82 at 3 years, and 0.76 at 5 years. In the GEO cohort, the AUCs reached 0.69 at 1 year, 0.74 at 3 years, and 0.75 at 5 years. An additional enrichment analysis indicated a significant upregulation of cytokine-related pathways, immune receptor activity, and other immune-related pathways in the high-risk group. Furthermore, the analysis revealed that the proportions of mast cells and plasma cells were significantly lower in the high-risk group compared to the low-risk group of PCa patients. Conversely, the proportion of regulatory T cells (Tregs) was significantly higher in the high-risk group than in the low-risk group. According to the qRT-PCR, Western blot, and IHC results, DRD4, SRC, AKR1C2, and AIFM2 expression was significantly higher in PCa than BPH. We also showed that the ferrostatin 1-treated LNCaP cells had higher expression levels of DRD4, SRC, and AKR1C2. A prognostic signature of eight ferroptosis-related genes (FRGs) that may accurately predict PCa patient outcomes was constructed and validated. FRGs may contribute to anti-tumor immunity and serve as therapeutic targets in PCa.

Integrating Molecular Biology and Network Pharmacology to Analyze the Antidepressant Mechanism of Glycyrrhizaglabra.

Antidepressants have adverse effects and induce drug resistance when used excessively or frequently. Therefore, adjuvants are needed to reduce the use of antidepressants during treatment. Traditional Chinese medicine (TCM) is an important adjunctive approach to depression with safety, environmental protection, and low toxicity. Glycyrrhizaglabra (licorice, GG) is a plant commonly used in various herbal remedies. We investigated the antidepressant activity of GG, its active constituents, and potential depression-related targets. We combined animal behavioral and molecular biological assays with network pharmacology to analyze the antidepressant mechanism of GG. GG extracts reversed lipopolysaccharide (LPS)-induced depression-like behavior in behavioral tests. We selected 56 active compounds and 695 target compounds of licorice from TCMSP. The PPI network screened 80 core targets for enrichment analysis. It shows that GG significantly affected neurodegeneration pathways, neuroactive ligand-receptor interaction, cAMP signaling pathway, serotonergic synapse, dopaminergic synapse, and MAPK signaling pathway. Mechanistic studies showed that GG reduced IL-1β, IL-6, and TNF-α levels, 5-HTRA1 expression, and GSK3β phosphorylation in mouse hippocampus. It also increased BDNF and DRD1 expression and CREB and ERK1/2 phosphorylation. It shows that GG acted on these proteins to affect multiple pathways that mediate the pathogenesis of depression.

Dopamine Receptors and TAAR1 Functional Interaction Patterns in the Duodenum Are Impaired in Gastrointestinal Disorders.

Currently, there is a growing amount of evidence for the involvement of dopamine receptors and the functionally related trace amine-associated receptor, TAAR1, in upper intestinal function. In the present study, we analyzed their expression in the duodenum using publicly accessible transcriptomic data. We revealed the expression of DRD1, DRD2, DRD4, DRD5, and TAAR1 genes in different available datasets. The results of the gene ontology (GO) enrichment analysis for DRD2 and especially TAAR1 co-expressed genes were consistent with the previously described localization of D2 and TAAR1 in enteric neurons and secretory cells, respectively. Considering that co-expressed genes are more likely to be involved in the same biological processes, we analyzed genes that are co-expressed with TAAR1, DRD2, DRD4, and DRD5 genes in healthy mucosa and duodenal samples from patients with functional dyspepsia (FD) or diabetes-associated gastrointestinal symptoms. Both pathological conditions showed a deregulation of co-expression patterns, with a high discrepancy between DRDs and TAAR1 co-expressed gene sets in normal tissues and patients' samples and a loss of these genes' functional similarity. Meanwhile, we discovered specific changes in co-expression patterns that may suggest the involvement of TAAR1 and D5 receptors in pathologic or compensatory processes in FD or diabetes accordingly. Despite our findings suggesting the possible role of TAAR1 and dopamine receptors in functional diseases of the upper intestine, underlying mechanisms need experimental exploration and validation.

Sex and Age Differences in Ontogeny of Alloparenting: A Relation to Forebrain DRD1, DRD2, and HTR2A mRNA Expression?

Alloparenting refers to the practice of caring for the young by individuals other than their biological parents. The relationship between the dynamic changes in psychological functions underlying alloparenting and the development of specific neuroreceptors remains unclear. Using a classic 10-day pup sensitization procedure, together with a pup preference and pup retrieval test on the EPM (elevated plus maze), we showed that both male and female adolescent rats (24 days old) had significantly shorter latency than adult rats (65 days old) to be alloparental, and their motivation levels for pups and objects were also significantly higher. In contrast, adult rats retrieved more pups than adolescent rats even though they appeared to be more anxious on the EPM. Analysis of mRNA expression using real-time-PCR revealed a higher dopamine D2 receptor (DRD2) receptor expression in adult hippocampus, amygdala, and ventral striatum, along with higher dopamine D1 receptor (DRD1) receptor expression in ventral striatum compared to adolescent rats. Adult rats also showed significantly higher levels of 5-hydroxytryptamine receptor 2A (HTR2A) receptor expression in the medial prefrontal cortex, amygdala, ventral striatum, and hypothalamus. These results suggest that the faster onset of alloparenting in adolescent rats compared to adult rats, along with the psychological functions involved, may be mediated by varying levels of dopamine DRD1, DRD2, and HTR2A in different forebrain regions.

Expression Profiles of Dopamine-Related Genes and miRNAs Regulating Their Expression in Breast Cancer.

This study aimed to assess the expression profile of messenger RNA (mRNA) and microRNA (miRNA) related to the dopaminergic system in five types of breast cancer in Polish women. Patients with five breast cancer subtypes were included in the study: luminal A (n = 130), luminal B (n = 196, including HER2-, n = 100; HER2+, n = 96), HER2+ (n = 36), and TNBC (n = 43); they underwent surgery, during which tumor tissue was removed along with a margin of healthy tissue (control material). The molecular analysis included a microarray profile of mRNAs and miRNAs associated with the dopaminergic system, a real-time polymerase chain reaction preceded by reverse transcription for selected genes, and determinations of their concentration using enzyme-linked immunosorbent assay (ELISA). The conducted statistical analysis showed that five mRNAs statistically significantly differentiated breast cancer sections regardless of subtype compared to control samples; these were dopamine receptor 2 (DRD2), dopamine receptor 3 (DRD3), dopamine receptor 25 (DRD5), transforming growth factor beta 2 (TGF-β-2), and caveolin 2 (CAV2). The predicted analysis showed that hsa-miR-141-3p can regulate the expression of DRD2 and TGF-β-2, whereas hsa-miR-4441 is potentially engaged in the expression regulation of DRD3 and DRD5. In addition, the expression pattern of DRD5 mRNA can also be regulated by has-miR-16-5p. The overexpression of DRD2 and DRD3, with concomitant silencing of DRD5 expression, confirms the presence of dopaminergic abnormalities in breast cancer patients. Moreover, these abnormalities may be the result of miR-141-3P, miR-16-5p, and miR-4441 activity, regulating proliferation or metastasis.

Dopamine-driven Increase in IL-1β in Myeloid Cells is Mediated by Differential Dopamine Receptor Expression and Exacerbated by HIV.

The catecholamine neurotransmitter dopamine is classically known for regulation of central nervous system (CNS) functions such as reward, movement, and cognition. Increasing evidence also indicates that dopamine regulates critical functions in peripheral organs and is an important immunoregulatory factor. We have previously shown that dopamine increases NF-κB activity, inflammasome activation, and the production of inflammatory cytokines such as IL-1β in human macrophages. As myeloid lineage cells are central to the initiation and resolution of acute inflammatory responses, dopamine-mediated dysregulation of these functions could both impair the innate immune response and exacerbate chronic inflammation. However, the exact pathways by which dopamine drives myeloid inflammation are not well defined, and studies in both rodent and human systems indicate that dopamine can impact the production of inflammatory mediators through both D1-like dopamine receptors (DRD1, DRD5) and D2-like dopamine receptors (DRD2, DRD3, and DRD4). Therefore, we hypothesized that dopamine-mediated production of IL-1β in myeloid cells is regulated by the ratio of different dopamine receptors that are activated. Our data in primary human monocyte-derived macrophages (hMDM) indicate that DRD1 expression is necessary for dopamine-mediated increases in IL-1β, and that changes in the expression of DRD2 and other dopamine receptors can alter the magnitude of the dopamine-mediated increase in IL-1β. Mature hMDM have a high D1-like to D2-like receptor ratio, which is different relative to monocytes and peripheral blood mononuclear cells (PBMCs). We further confirm in human microglia cell lines that a high ratio of D1-like to D2-like receptors promotes dopamine-induced increases in IL-1β gene and protein expression using pharmacological inhibition or overexpression of dopamine receptors. RNA-sequencing of dopamine-treated microglia shows that genes encoding functions in IL-1β signaling pathways, microglia activation, and neurotransmission increased with dopamine treatment. Finally, using HIV as an example of a chronic inflammatory disease that is substantively worsened by comorbid substance use disorders (SUDs) that impact dopaminergic signaling, we show increased effects of dopamine on inflammasome activation and IL-1β in the presence of HIV in both human macrophages and microglia. These data suggest that use of addictive substances and dopamine-modulating therapeutics could dysregulate the innate inflammatory response and exacerbate chronic neuroimmunological conditions like HIV. Thus, a detailed understanding of dopamine-mediated changes in inflammation, in particular pathways regulating IL-1β, will be critical to effectively tailor medication regimens.

Iloperidone and Temozolomide Synergistically Inhibit Growth, Migration and Enhance Apoptosis in Glioblastoma Cells.

Glioblastoma (GBM) is a fatal astrocytic glioma with poor prognosis and treatment resistance. Repurposing potential FDA-approved drugs like anti-psychotics can address the concerns in a timely and cost-effective manner. Epidemiological studies have shown that patients with schizophrenic using anti-psychotics have a low incidence of GBM. Therefore, we aimed to investigate the therapeutic potential of atypical anti-psychotic Iloperidone (ILO) alone and in combination with Temozolomide (TMZ) against GBM. The study assessed the growth inhibitory effect of ILO, TMZ, and their combination (ILO + TMZ) on U-87MG and T-98G cell lines using an MTT assay. The drug interaction coefficient (CDI) was determined, and doses with synergistic effects were used for subsequent experiments, including migratory, invasion, and TUNEL assays. The expressions of DRD2, β-catenin, Dvl2, Twist, and Slug were assessed by RTq-PCR, whereas the β-catenin protein expression was also determined by immunocytochemistry. ILO (p < 0.05) and TMZ (p < 0.01) significantly inhibited the growth of U-87MG cells at all tested doses. The combination of 60 µM of both drugs showed synergistic activity with CDI < 1. The inhibition of migration and apoptosis was more pronounced in the case of combination treatment (p < 0.001). Inhibition of the invading cells was also found to be significant in ILO- and combination-treated groups (p < 0.001). ILO and combination treatment also significantly downregulated the expression of DRD2, while TMZ upregulated the expression (p < 0.001). The expressions of β-catenin (p < 0.001), Dvl2 (p < 0.001), Twist (p < 0.001), and Slug (p < 0.001) were also significantly downregulated in all treatment groups as compared to the vehicle control. The data suggest that ILO possesses strong growth inhibitory activity, possibly due to its effect on DRD2 and β-catenin expression and has the potential to be repurposed against GBM.

PM2.5 exposure contributes to anxiety and depression-like behaviors via phenyl-containing compounds interfering with dopamine receptor

As a global problem, fine particulate matter (PM2.5) really needs local fixes. Considering the increasing epidemiological relevance to anxiety and depression but inconsistent toxicological results, the most important question is to clarify whether and how PM2.5 causally contributes to these mental disorders and which components are the most dangerous for crucial mitigation in a particular place. In the present study, we chronically subjected male mice to a real-world PM2.5 exposure system throughout the winter heating period in a coal combustion area and revealed that PM2.5 caused anxiety and depression-like behaviors in adults such as restricted activity, diminished exploratory interest, enhanced repetitive stereotypy, and elevated acquired immobility, through behavioral tests including open field, elevated plus maze, marble-burying, and forced swimming tests. Importantly, we found that dopamine signaling was perturbed using mRNA transcriptional profile and bioinformatics analysis, with Drd1 as a potential target. Subsequently, we developed the Drd1 expression-directed multifraction isolating and nontarget identifying framework and identified a total of 209 compounds in PM2.5 organic extracts capable of reducing Drd1 expression. Furthermore, by applying hierarchical characteristic fragment analysis and molecular docking and dynamics simulation, we clarified that phenyl-containing compounds competitively bound to DRD1 and interfered with dopamine signaling, thereby contributing to mental disorders. Taken together, this work provides experimental evidence for researchers and clinicians to identify hazardous factors in PM2.5 and prevent adverse health outcomes and for local governments and municipalities to control source emissions for diminishing specific disease burdens.

Dopamine D2 receptors in the bed nucleus of the stria terminalis modulate alcohol-related behaviors

Dysregulation of the dopamine (DA) system is a hallmark of substance use disorders, including alcohol use disorder (AUD). Of the DA receptor subtypes, the DA D2 receptors (D2Rs) play a key role in the reinforcing effects of alcohol. D2Rs are expressed in numerous brain regions associated with the regulation of appetitive behaviors. One such region is the bed nucleus of the stria terminalis (BNST), which has been linked to the development and maintenance of AUD. Recently, we identified alcohol withdrawal-related neuroadaptations in the periaqueductal gray/dorsal raphe to BNST DA circuit in male mice. However, the role of D2R-expressing BNST neurons in voluntary alcohol consumption is not well characterized. In this study, we used a CRISPR-Cas9-based viral approach, to selectively reduce the expression of D2Rs in BNST GABA neurons (BNSTvgat Drd2) and interrogated the impact on alcohol-related behaviors. In male mice, reduced BNSTvgat Drd2 expression potentiated the stimulatory effects of alcohol and increased voluntary consumption of 20% w/v alcohol in a two-bottle choice intermittent access paradigm. This effect was not specific to alcohol, as BNSTvgat Drd2 knockdown also increased sucrose intake in male mice. Interestingly, reduction in BNSTvgat Drd2 expression in female mice did not alter alcohol-related behaviors but lowered the threshold for mechanical pain sensitivity. Collectively, our findings suggest a role for postsynaptic BNST D2Rs in the modulation of sex-specific behavioral responses to alcohol and sucrose.

Study on mechanism of regulation of sex hormones in treatment of hyperprolactinemia-induced ovulatory disorder infertility with Bushen Culuan Formula

Transcriptomics was used to investigate the mechanism of action of Bushen Culuan Formula in the treatment of infertility caused by hyperprolactinemia(HPRL), and animal experiments were carried out to verify the results. After establishing an animal model of HPRL-induced infertility, the mice were divided into normal group, model group, Bushen Culuan Formula groups with high-, medium-, and low-doses, and bromocriptine group, and they were observed in terms of the estrous cycle, gonadal index, serum sex hormones, morphology of ovary and mammary gland, follicle count, and fertility. The results showed that the Bushen Culuan Formula could effectively restore the estrous cycle, down-regulate the levels of prolactin(PRL), follicle-stimulating hormone(FSH), and luteinizing hormone(LH), up-regulate the level of estradiol(E_2), increase the number of primordial follicles and sinus follicles, and improve the ovulation rate and fertility of mice. Through RNA sequencing combined with biosignature analysis, Bushen Culuan Formula may regulate the metabolism of lipids, antioxidant enzymes, and other substances in the cells of the ovary and pituitary gland through the signaling pathways of cAMP-PKA, Kiss-1/GPR54, and Hippo and exert therapeutic effects. The results of animal experiments showed that Bushen Culuan Formula could up-regulate serum dopamine(DA) level and pituitary DRD2 expression, down-regulate hypothalamus and ovary cAMP levels, as well as protein expressions of the pituitary gland and ovary PKA, CREB, and p-CREB, and treat HPRL-induced infertility by regulating the cAMP-PKA signaling pathway.

Lesion network of oculogyric crises maps to brain dopaminergic transcriptomic signature.

Oculogyric crises are acute episodes of sustained, typically upward, conjugate deviation of the eyes. Oculogyric crises usually occur as the result of acute D2-dopamine receptor blockade, but the brain areas causally involved in generating this symptom remain elusive. Here, we used data from 14 previously reported cases of lesion-induced oculogyric crises and employed lesion network mapping to identify their shared connections throughout the brain. This analysis yielded a common network that included basal ganglia, thalamic and brainstem nuclei, as well as the cerebellum. Comparison of this network with gene expression profiles associated with the dopamine system revealed spatial overlap specifically with the gene coding for dopamine receptor type 2 (DRD2), as defined by a large-scale transcriptomic database of the human brain. Furthermore, spatial overlap with DRD2 and DRD3 gene expression was specific to brain lesions associated with oculogyric crises when contrasted to lesions that led to other movement disorders. Our findings identify a common neural network causally involved in the occurrence of oculogyric crises and provide a pathophysiological link between lesion locations causing this syndrome and its most common pharmacological cause, namely DRD2 blockade.

Predictive Factors for Methadone Maintenance Treatment Compliance: Exploring Resistance and Tolerance in Heroin Addiction

Background: Methadone maintenance treatment (MMT) has been a cornerstone in heroin addiction management. However, its efficacy varies among individuals. The complex interplay of genetic backgrounds and demographic data could influence the response to MMT in heroin addiction. No previous adoption study has aimed to merge these findings into a potential pre-treatment screening tool. Objectives: This study aimed to investigate the combined influence of dopamine and opioid receptors and receptor endocytosis machinery genes, individual genetic backgrounds, and demographic data on the response to MMT in patients with heroin addiction. Methods: We enrolled 80 heroin addicts receiving MMT for 3 months alongside 80 healthy individuals in a comparative study. The approach utilized multinomial, linear, and binary logistic regression analyses to investigate the interplay of genetic factors (DRD1-5, opioid receptors [µ1, δ1, and κ1], DNM1L, RAB22A, and COMT), demographic independent variables, including, family history, heroin duration, age onset, heroin dose, and methadone dose, and clinical markers Subjective Opiate Withdrawal Scale (SOWS) with compliance with MMT protocols. Results: Results revealed that a positive family history and a higher level of heroin dose significantly predicted poor compliance to MMT. Additionally, the patients with lower expression levels of DRD2 and higher expression levels of DNM1L and COMT genes were at higher risk for poor compliance with the treatment. Conclusions: By utilizing a comprehensive dataset of gene expression profiles and demographic and clinical parameters, this study developed a regression model predicting resistance or response to methadone. This innovative approach seeks to bridge the gap between pharmacogenomics and clinical practice and offer a potential pre-treatment screening tool for personalized MMT strategies in opioid addiction management. The obtained findings hold intriguing promise for future research, potentially unlocking deeper insights into the underlying risk factors of addiction.

Effects of the Phosphodiesterase 10A Inhibitor MR1916 on Alcohol Self-Administration and Striatal Gene Expression in Post-Chronic Intermittent Ethanol-Exposed Rats.

Alcohol use disorder (AUD) requires new neurobiological targets. Problematic drinking involves underactive indirect pathway medium spiny neurons (iMSNs) that subserve adaptive behavioral selection vs. overactive direct pathway MSNs (dMSNs) that promote drinking, with a shift from ventromedial to dorsolateral striatal (VMS, DLS) control of EtOH-related behavior. We hypothesized that inhibiting phosphodiesterase 10A (PDE10A), enriched in striatal MSNs, would reduce EtOH self-administration in rats with a history of chronic intermittent ethanol exposure. To test this, Wistar rats (n = 10/sex) with a history of chronic intermittent EtOH (CIE) vapor exposure received MR1916 (i.p., 0, 0.05, 0.1, 0.2, and 0.4 µmol/kg), a PDE10A inhibitor, before operant EtOH self-administration sessions. We determined whether MR1916 altered the expression of MSN markers (Pde10a, Drd1, Drd2, Penk, and Tac1) and immediate-early genes (IEG) (Fos, Fosb, ΔFosb, and Egr1) in EtOH-naïve (n = 5-6/grp) and post-CIE (n = 6-8/grp) rats. MR1916 reduced the EtOH self-administration of high-drinking, post-CIE males, but increased it at a low, but not higher, doses, in females and low-drinking males. MR1916 increased Egr1, Fos, and FosB in the DLS, modulated by sex and alcohol history. MR1916 elicited dMSN vs. iMSN markers differently in ethanol-naïve vs. post-CIE rats. High-drinking, post-CIE males showed higher DLS Drd1 and VMS IEG expression. Our results implicate a role and potential striatal bases of PDE10A inhibitors to influence post-dependent drinking.

Ameliorating effects of Acanthopanax koreanum extract and components on nicotine dependence and withdrawal symptoms.

Tobacco smoking is a serious health problem in society. While smoking rates are declining, smoking remains a serious risk to national health. Currently, there are several medications available to aid in smoking cessation. However, these medications have the disadvantages of low success rates in smoking cessation and various side effects. Therefore, natural-based smoking cessation aids are being suggested as a good alternative due to their accessibility and minimal side effects. The roots and stems of Acanthopanax koreanum (AK) Nakai, a plant that is native to Jeju Island, South Korea, have traditionally been used as tonic and sedatives. Moreover, eleutheroside B and chlorogenic acid are the main components of AK stem extract. In the present study, we investigated the effect of 70% ethanol AK extract and its components on ameliorating nicotine dependence and withdrawal symptoms by using behavioural tests in mice. In addition, alterations in the dopaminergic and DRD1-EPAC-ERK-CREB pathways were observed using dopamine ELISA and western blotting using mouse brains. Our findings demonstrate that the AK extract and its components effectively mitigated the effects of nicotine treatment in behavioural tests. Furthermore, it normalized the dopamine concentration and the expression level of nicotine acetylcholine receptor α7. Additionally, it was observed that AK extract and its components led to the normalization of DRD1, ERK and CREB expression levels. These results indicate that AK extract exhibits effects in ameliorating nicotine dependence behaviour and alleviating withdrawal symptoms. Moreover, EB and CGA are considered potential marker components of AK extract.

Identification of genes regulated by trait sensitivity to negative feedback and prolonged alcohol consumption in rats.

The results of our previous studies demonstrated that low sensitivity to negative feedback (NF) is associated with increased vulnerability to the development of compulsive alcohol-seeking in rats. In the present study, we investigated the molecular underpinnings of this relationship. Using TaqMan Gene Expression Array Cards, we analyzed the expression of the genes related to NF sensitivity and alcohol metabolism in three cortical regions (medial prefrontal cortex [mPFC], anterior cingulate cortex [ACC], orbitofrontal cortex [OFC]) and two subcortical regions (nucleus accumbens [Nacc], amygdala [Amy]). Gene expression differences were confirmed at the protein level with Western blot. Sensitivity to NF was characterized by differences in Gad2, Drd2, and Slc6a4 expression in the ACC, Maoa in the mPFC, and Gria1, Htr3a, and Maoa in the OFC. Chronic alcohol consumption was associated with differences in the expression of Comt and Maoa in the ACC, Comt, Adh1, and Htr2b in the mPFC, Adh1, and Slc6a4 in the Nacc, Gad2, and Htr1a in the OFC, and Drd2 in the Amy. Interactions between the sensitivity to NF and alcohol consumption were observed in the expression of Gabra1, Gabbr2, Grin2a, Grin2b, and Grm3 in the ACC, and Grin2a in the OFC. The observed differences were confirmed at the protein level for MAO-A in the mPFC, and ADH1 in the mPFC and Nacc. Our findings contribute to a better understanding of the molecular mechanisms underlying the relationship between trait sensitivity to NF and compulsive alcohol consumption.

Theobromine improves hyperactivity, inattention, and working memory via modulation of dopaminergic neural function in the frontal cortex of spontaneously hypertensive rats.

Attention-deficit/hyperactivity disorder (ADHD) is a developmental disorder and dopaminergic dysfunction in the prefrontal cortex (PFC) may play a role. Our previous research indicated that theobromine (TB), a methylxanthine, enhances cognitive function in rodents via the PFC. This study investigates TB's effects on hyperactivity and cognitive function in stroke-prone spontaneously hypertensive rats (SHR), an ADHD animal model. Male SHRs (6-week old) received a diet containing 0.05% TB for 40 days, while control rats received normal diets. Age-matched male Wistar-Kyoto rats (WKY) served as genetic controls. During the TB administration period, we conducted open-field tests and Y-maze tasks to evaluate hyperactivity and cognitive function, then assessed dopamine concentrations and tyrosine hydroxylase (TH), dopamine receptor D1-5 (DRD1-5), dopamine transporter (DAT), vesicular monoamine transporter-2 (VMAT-2), synaptosome-associated protein-25 (SNAP-25), and brain-derived neurotrophic factor (BDNF) expressions in the PFC. Additionally, the binding affinity of TB for the adenosine receptors (ARs) was evaluated. Compared to WKY, SHR exhibited hyperactivity, inattention and working memory deficits. However, chronic TB administration significantly improved these ADHD-like behaviors in SHR. TB administration also normalized dopamine concentrations and expression levels of TH, DRD2, DRD4, SNAP-25, and BDNF in the PFC of SHR. No changes were observed in DRD1, DRD3, DRD5, DAT, and VMAT-2 expression between SHR and WKY rats, and TB intake had minimal effects. TB was found to have affinity binding to ARs. These results indicate that long-term TB supplementation mitigates hyperactivity, inattention and cognitive deficits in SHR by modulating dopaminergic nervous function and BDNF levels in the PFC, representing a potential adjunctive treatment for ADHD.