Purpose: For understanding the neurochemical mechanism of neuropsychiatric conditions associated with cognitive deficits it is of major relevance to elucidate the influence of serotonin (5-HT) agonists and antagonists on memory function as well dopamine (DA) and 5-HT release and metabolism. In the present study, we assessed the effects of the 5-HT receptor agonist 2,5-dimethoxy-4-iodoamphetamine (DOI) and the 5-HT receptor altanserin (ALT) on object and place recognition memory and cerebral neurotransmitters and metabolites in the rat.
Methods: Rats underwent a 5-min exploration trial in an open field with two identical objects.
Introduction: Patients with inflammatory bowel disease (IBD) are predisposed to the reactivation of viral infections such as cytomegalovirus (CMV). Clinical discrimination of disease flares and colonic CMV reactivation is difficult in patients with established diagnosis of IBD, and there are no reliable noninvasive diagnostic tools yet. Furthermore, the influence of novel therapeutics including biologicals and Janus kinase inhibitors on the risk of CMV colitis is unclear.
View Article and Find Full Text PDFBoth dopamine (DA) and serotonin (5-HT) play key roles in numerous functions including motor control, stress response and learning. So far, there is scarce or conflicting evidence about the effects of 5-HT1A and 5-HT2A receptor (R) agonists and antagonists on recognition memory in the rat. This also holds for their effect on cerebral DA as well as 5-HT release.
View Article and Find Full Text PDFIn the present studies, we assessed the effect of the 5-HT receptor (R) agonist 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) on motor and exploratory behaviors, object and place recognition and dopamine transporter (DAT) and serotonin transporter (SERT) binding in the rat brain. In Experiment I, motor/exploratory behaviors were assessed in an open field after injection of either 8-OH-DPAT (0.1 and 3 mg/kg) or vehicle for 30 min without previous habituation to the open field.
View Article and Find Full Text PDFAberrant CD4 T cell reactivity against intestinal microorganisms is considered to drive mucosal inflammation in inflammatory bowel diseases. The disease-relevant microbial species and the corresponding microorganism-specific, pathogenic T cell phenotypes remain largely unknown. In the present study, we identified common gut commensal and food-derived yeasts, as direct activators of altered CD4 T cell reactions in patients with Crohn's disease (CD).
View Article and Find Full Text PDFBackground: Histological disease severity assessment in ulcerative colitis [UC] has become a mainstay in the definition of clinical endpoints ['histological remission'] in clinical trials of UC. Several scores have been established in the microscopic assessment of disease activity, but the Nancy index [NI] stands out as being the histological index with the fewest scoring items. To what extent histological assessment using the NI is affected by interobserver reliability in a real-word setting is poorly understood.
View Article and Find Full Text PDFGenetic variants in the DNA methyltransferase 3 A (DNMT3A) locus have been associated with inflammatory bowel disease (IBD). DNMT3A is part of the epigenetic machinery physiologically involved in DNA methylation. We show that DNMT3A plays a critical role in maintaining intestinal homeostasis and gut barrier function.
View Article and Find Full Text PDFBackground And Aims: Treatment with tumor necrosis factor α (TNFα) antagonists in IBD patients suffers from primary non-response rates of up to 40%. Biomarkers for early prediction of therapy success are missing. We investigated the dynamics of gene expression and DNA methylation in blood samples of IBD patients treated with the TNF antagonist infliximab and analyzed the predictive potential regarding therapy outcome.
View Article and Find Full Text PDFNeurosci Biobehav Rev
October 2022
Rats and mice are used for studying neuronal circuits underlying recognition memory due to their ability to spontaneously remember the occurrence of an object, its place and an association of the object and place in a particular environment. A joint employment of lesions, pharmacological interventions, optogenetics and chemogenetics is constantly expanding our knowledge of the neural basis for recognition memory of object, place, and their association. In this review, we summarize current studies on recognition memory in rodents with a focus on the novel object preference, novel location preference and object-in-place paradigms.
View Article and Find Full Text PDFImmunosuppressants and biologicals are widely used therapeutics for various chronic inflammatory diseases (CID). To gain more detailed insight into their downstream effects, we examined their impact on serum immunoglobulin G (IgG) glycosylation. We analyzed IgG subclass-specific fragment crystallizable (Fc) N-glycosylation in patients suffering from various CID using the LC-MS approach.
View Article and Find Full Text PDFThe precise cortical and subcortical mechanisms of Tourette syndrome (TS) are still not fully understood. In the present retrospective analysis, adolescent and adult medication-naïve patients showed increased DA transporter (DAT) binding in nucleus caudate (CAUD), putamen (PUT) and/or whole neostriatum (NSTR). D receptor (R) binding and DA release were not different from controls throughout the nigrostriatal and mesolimbocortical system.
View Article and Find Full Text PDFAlterations in cognitive functions, social behaviors and stress reactions are commonly diagnosed in chronic mental illnesses (CMI). Animal models expressing mutant genes associated to CMI represent either rare mutations or those contributing only minimally to genetic risk. Non-genetic causes of CMI can be modeled by disturbing downstream signaling pathways, for example by inducing protein misassembly or aggregation.
View Article and Find Full Text PDFSerotonin(5-HT)ergic projections run from the raphe nuclei to dopamin(DA)ergic cells in substantia nigra/ventral tegmental area (SN/VTA) and to the terminal fields of DA neurons in nucleus accumbens, caudateputamen and neocortex. In the present studies, we assessed the effect of the 5-HT receptor (R) antagonist N-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-N-2-pyridinylcyclohexanecarbox-amide maleate (WAY-100635) on motor and exploratory behaviors and on DR binding in the rat brain with in vivo imaging methods. DR binding was determined in the same animals after systemic application of WAY-100635 (0.
View Article and Find Full Text PDFBackground And Aims: Inflammatory bowel disease [IBD] is a chronic relapsing disorder of the gastrointestinal tract, which generally manifests as Crohn's disease [CD] or ulcerative colitis [UC]. These subtypes are heterogeneous in terms of disease location and histological features, while sharing common clinical presentation, genetic associations and, thus, common immune regulatory pathways.
Methods: Using miRNA and mRNA coupled transcriptome profiling and systems biology approaches, we report a comprehensive analysis of blood transcriptomes from treatment-naïve [n = 110] and treatment-exposed [n = 177] IBD patients as well as symptomatic [n = 65] and healthy controls [n = 95].
Background: The persistence of the SARS-CoV2 pandemic, partly due to the appearance of highly infectious variants, has made booster vaccinations necessary for vulnerable groups. Questions remain as to which cohorts require SARS-CoV2 boosters. However, there is a critical lack of data on the dynamics of vaccine responses in patients with chronic inflammatory diseases (CID) undergoing immunosuppressive/disease modifying anti-rheumatic (DMARD) treatment.
View Article and Find Full Text PDFThe 5-HT receptor (R) is known to modulate dopamine (DA) release in the mammalian brain. Altanserin (ALT) and 2,5-dimethoxy-4-iodoamphetamine (DOI) act as 5-HTR antagonist and agonist, respectively. In the present study, we assessed the effects of ALT and DOI on motor and exploratory behaviors and on DR binding in the rat brain with imaging methods.
View Article and Find Full Text PDFDisturbances of dopamine (DA), serotonin (5-HT) and/or norepinephrine (NE) functions are implied in attention-deficit hyperactivity disorder (ADHD). However, the precise cortical and subcortical mechanisms are still not fully understood. In the present survey, we conducted a PUBMED search, which provided 37 investigations with PET and SPECT on 419 ADHD patients and 490 controls.
View Article and Find Full Text PDFBackground & Aims: A large unmet therapeutic need exists in inflammatory bowel disease (IBD). Inhibition of interleukin (IL)-6 appears to be effective, but the therapeutic benefit of a complete IL6/IL6 receptor (IL6R) blockade is limited by profound immunosuppression. Evidence has emerged that chronic proinflammatory activity of IL6 is mainly mediated by trans-signaling via a complex of IL6 bound to soluble IL6R engaging the gp130 co-receptor without the need for membrane-bound IL6R.
View Article and Find Full Text PDFJ Crohns Colitis
August 2021
The dopamine (DA) system has a profound impact on reward-motivated behavior and is critically involved in neurodevelopmental disorders, such as autism spectrum disorder (ASD). Although DA defects are found in autistic patients, it is not well defined how the DA pathways are altered in ASD and whether DA can be utilized as a potential therapeutic agent for ASD. To this end, we employed a phenotypic and a genetic ASD model, i.
View Article and Find Full Text PDFIn this review, a series of experiments is presented, in which γ-amino butyric acid (GABA)ergic and glutamatergic effects on dopamine function in the rat nigrostriatal and mesolimbic system was systematically assessed after pharmacological challenge with GABAA receptor (R) and and N-methyl d-aspartate (NMDA)R agonists and antagonists. In these studies, [123I]iodobenzamide binding to the D2/3R was mesured in nucleus accumbens (NAC), caudateputamen (CP), substantia nigra/ventral tegmental area (SN/VTA), frontal (FC), motor (MC) and parietal cortex (PC) as well as anterior (aHIPP) and posterior hippocampus (pHIPP) with small animal SPECT in baseline and after injection of either the GABAAR agonist muscimol (1 mg/kg), the GABAAR antagonist bicuculline (1 mg/kg), the NMDAR agonist d-cycloserine (20 mg/kg) or the NMDAR antagonist amantadine (40 mg/kg). Muscimol reduced D2/3R binding in NAC, CP, SN/VTA, THAL and pHIPP, while, after amantadine, decreases were confined to NAC, CP and THAL.
View Article and Find Full Text PDFBackground: In chronic fatigue syndrome (CFS) little is known about how partner-related factors influence patients' fatigue symptoms and treatment outcome. We examined partners' fatigue severity, and determined the role of partner-related factors for patients' symptoms and the outcome of cognitive behavioural therapy (CBT).
Methods: 1356 CFS patients and their partners completed baseline measures of fatigue severity (Checklist Individual Strength), causal attributions of symptoms, partner responses to patient symptoms, and relationship satisfaction.