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Sex differences in learned fear regarding aversive gastrointestinal stimuli could play a role in the female preponderance of chronic abdominal pain. In a fear conditioning model with rectal pain as unconditioned stimulus (US), we compared healthy males and females with respect to neural responses during aversive visceral learning, extinction and re-activation of fear memory (i.e., reinstatement). To do so, conditioned visual stimuli (CS(+)) were consistently paired with painful rectal distensions as US, while different visual stimuli (CS(-)) were presented without US. During extinction, both CSs were presented without US, whereas during reinstatement, a single, unpaired US was presented. In region-of-interest analyses, sexes were compared with respect to conditioned anticipatory neural activation (CS(+)>CS(-)). The results revealed that in late acquisition, CS+ presentation induced significantly greater anticipatory activation of the insula in women. During extinction, women demonstrated reduced activation of the posterior cingulate cortex. During reinstatement, the CS(+) led to greater activation of the hippocampus, thalamus and cerebellum in women. These group effects in neural activation during learning and memory processes were not accounted for by sex differences in pain thresholds, pain ratings, or stress parameters. In conclusion, this is the first study to support sex differences in neural processes mediating aversive visceral learning. Our finding of enhanced neural responses during reinstatement in key brain areas relevant for memory suggests enhanced reactivation of old fear memory trace in women. Sex differences in "gut memories" could play a role in the female preponderance of chronic abdominal pain.
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Encéfalo/fisiopatologia , Medo/fisiologia , Dor Visceral/fisiopatologia , Adulto , Mapeamento Encefálico , Condicionamento Clássico/fisiologia , Feminino , Humanos , Hidrocortisona/análise , Imageamento por Ressonância Magnética , Masculino , Fatores Sexuais , Adulto JovemRESUMO
Background: Teriflunomide is a once-daily oral disease-modifying therapy (DMT) for the treatment of relapsing-remitting multiple sclerosis (RRMS). Only limited information is available about its real-world use and changes over time. Objectives: To collect real-world data on teriflunomide use in clinical routine (and comparison to the previously conducted study TAURUS-MS). Design: National, open, non-interventional, prospective, multicenter study. Methods: TAURUS-MS II was conducted at 220 German sites between July 2017 and March 2022, including RRMS patients treated with teriflunomide. Data on patient demographics, MS history, previous treatment, therapy satisfaction, and safety were collected. Results: In total, 752 patients were included (65% female) with a mean age (±standard deviation) of 43 ± 11 years. Sixty-six percent had DMT before, and 46% had discontinued their last pretreatment ≤6 months prior to study entry. Among the latter, previous DMTs were interferon (21%), glatiramer acetate (11%), and dimethyl fumarate (9%), and reasons for discontinuation were adverse events (AEs; 55%) and insufficient efficacy (16%). Over 24 months, the mean treatment Satisfaction Questionnaire for Medication scores improved by 6 ± 29 points on effectiveness, 8 ± 20 on convenience, and 12 ± 25 on global satisfaction. The mean number of MS relapses decreased from 0.81 ± 0.81 in the 24 months prior to 0.27 ± 0.57 within 24 months after study entry. Non-serious AEs occurred in 423 patients (56%) and serious AEs in 49 patients (7%). Most reported AEs were alanine aminotransferase increase (11%), hypertension (8%), and alopecia (7%). Compared to TAURUS-MS, patients in TAURUS-MS II were younger, had a higher employment rate, and a higher share of treatment-naïve patients. Conclusion: Mean number of relapses was significantly reduced. Patient satisfaction was significantly improved compared to previous DMT. Tolerability was comparable to previous trials. Trial registration: Bundesinstitut für Arzneimittel und Medizinprodukte public database for non-interventional studies, number 7138.
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Increases in peripheral cytokines during acute inflammation may affect various neuropsychological functions. The aim of this functional magnetic resonance imaging (fMRI) study was to investigate the effects of acute endotoxemia on mood and the neural response to emotionally aversive visual stimuli in healthy human subjects. In a double-blind, randomized crossover study, 18 healthy males received a bolus injection of bacterial lipopolysaccharide (LPS; 0.4 ng/kg) or saline. Plasma levels of pro- and anti-inflammatory cytokines and cortisol as well as mood ratings were analyzed together with the blood-oxygen-level dependent (BOLD) response during the presentation of aversive versus neutral pictures. Endotoxin administration induced pronounced transient increases in plasma levels of TNF-α, IL-1ra, IL-6, IL-10, and cortisol. Positive mood was decreased and state anxiety increased. In addition, activation of right inferior orbitofrontal cortex (OFC) in response to emotional visual stimuli was significantly increased in the LPS condition. Increased prefrontal activation during the presentation of emotional material may reflect enhanced cognitive regulation of emotions as an adaptive response during an acute inflammation. These findings may have implications for the putative role of inflammatory processes in the pathophysiology of depression.
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Mapeamento Encefálico , Encéfalo/fisiopatologia , Emoções/fisiologia , Endotoxemia/psicologia , Adulto , Encéfalo/efeitos dos fármacos , Citocinas/sangue , Método Duplo-Cego , Endotoxemia/sangue , Humanos , Hidrocortisona/sangue , Interpretação de Imagem Assistida por Computador , Inflamação/psicologia , Lipopolissacarídeos/toxicidade , Imageamento por Ressonância Magnética , MasculinoRESUMO
BACKGROUND AND PURPOSE: Toll like receptor 4 (TLR4) is the major recognition receptor for lipopolysaccharides and plays a major role in the inflammatory response. CD11b is expressed on the surface of many leukocytes including monocytes. The CD11b/CD18 complex is involved in the inflammatory response by mediating migration and adhesion of leukocytes. The aim of this human in vivo study was to investigate the expression of TLR4 and CD11b on the surface of human monocytes after in vivo low-dose LPS stimulation. METHODS: We performed a double-blind, randomized crossover study with 16 healthy males who received a bolus injection of bacterial lipopolysaccharide (LPS; 0.4ng/kg) or normal saline. Vital parameters, blood counts, serum cytokine levels, the expression of TLR4, and CD11b on CD14 positive cells were analyzed. RESULTS: The experimentally induced inflammatory response was reflected by transient increases in body temperature, circulating leukocyte numbers, and plasma levels of pro- (TNF-α, IL-6) and anti-inflammatory cytokines (IL-10, IL-1ra). In contrast to a significant increase in CD11b expression, no changes in TLR4 expression on circulating monocytes were detectable. CONCLUSION: Early changes in TLR4 expression on circulating monocytes are not necessarily part of the inflammatory response to low dose LPS in humans whereas the detected increase of CD11b expression might already be sufficient for optimized recognition and signalling.
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Lipopolissacarídeos/farmacologia , Modelos Biológicos , Monócitos/metabolismo , Receptor 4 Toll-Like/metabolismo , Contagem de Células Sanguíneas , Pressão Sanguínea/efeitos dos fármacos , Antígeno CD11b/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Citocinas/sangue , Frequência Cardíaca/efeitos dos fármacos , Humanos , Receptores de Lipopolissacarídeos/metabolismo , Masculino , Monócitos/efeitos dos fármacosRESUMO
Immunological responses to bacterial endotoxin can be behaviorally conditioned in rodents. However, it is unclear whether an acute systemic inflammatory response can be behaviorally conditioned in humans. Thus, in a double-blind placebo-controlled study, 20 healthy, male subjects received either a single injection of lipopolysaccharide (LPS) or saline together with a novel tasting beverage (conditioned stimulus, CS). Five days later, all subjects received a saline injection and were re-exposed to the CS. Blood was drawn prior to as well as 0.5, 1.5, 3, 4, 6, and 24 h after LPS administration or CS re-exposure. Endotoxin administration led to transient increases in plasma concentrations of interleukin (IL)-6, IL-10, and tumor necrosis factor (TNF)-α and to a significant rise in body temperature. Sole presentation of the CS during evocation did induce neither alterations in body temperature nor changes in plasma cytokine levels. However, subjects in the experimental group rated the smell of the CS significantly more aversive compared to the control group. Employing endotoxin as a US in a single trial taste-immune conditioning paradigm in humans shows a behaviorally conditioned smell aversion but no learned alterations in cytokine levels.
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Condicionamento Psicológico , Citocinas/sangue , Odorantes , Paladar , Adulto , Afeto/fisiologia , Ansiedade/fisiopatologia , Aprendizagem da Esquiva , Temperatura Corporal , Citocinas/fisiologia , Método Duplo-Cego , Humanos , Interleucina-10/sangue , Interleucina-10/fisiologia , Interleucina-6/sangue , Interleucina-6/fisiologia , Lipopolissacarídeos/farmacologia , Masculino , Paladar/imunologia , Paladar/fisiologia , Fatores de Tempo , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/fisiologiaRESUMO
Active immunization with amyloid-ß (Aß) peptide 1-42 reverses amyloid plaque deposition in the CNS of patients with Alzheimer's disease and in amyloid precursor protein transgenic mice. However, this treatment may also cause severe, life-threatening meningoencephalitis. Physiological responses to immunization with Aß(1-42) are poorly understood. In this study, we characterized cognitive and immunological consequences of Aß(1-42)/CFA immunization in C57BL/6 mice. In contrast to mice immunized with myelin oligodendrocyte glycoprotein (MOG)(35-55)/CFA or CFA alone, Aß(1-42)/CFA immunization resulted in impaired exploratory activity, habituation learning, and spatial-learning abilities in the open field. As morphological substrate of this neurocognitive phenotype, we identified a disseminated, nonfocal immune cell infiltrate in the CNS of Aß(1-42)/CFA-immunized animals. In contrast to MOG(35-55)/CFA and PBS/CFA controls, the majority of infiltrating cells in Aß(1-42)/CFA-immunized mice were CD11b(+)CD14(+) and CD45(high), indicating their blood-borne monocyte/macrophage origin. Immunization with Aß(1-42)/CFA was significantly more potent than immunization with MOG(35-55)/CFA or CFA alone in activating macrophages in the secondary lymphoid compartment and peripheral tissues. Studies with TLR2/4-deficient mice revealed that the TLR2/4 pathway mediated the Aß(1-42)-dependent proinflammatory cytokine release from cells of the innate immune system. In line with this, TLR2/4 knockout mice were protected from cognitive impairment upon immunization with Aß(1-42)/CFA. Thus, this study identifies adjuvant effects of Aß(1-42), which result in a clinically relevant neurocognitive phenotype highlighting potential risks of Aß immunotherapy.
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Vacinas contra Alzheimer/efeitos adversos , Peptídeos beta-Amiloides/imunologia , Imunidade Inata/imunologia , Transtornos da Memória/imunologia , Fragmentos de Peptídeos/imunologia , Vacinação/efeitos adversos , Adjuvantes Imunológicos/farmacologia , Vacinas contra Alzheimer/imunologia , Peptídeos beta-Amiloides/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Encéfalo/imunologia , Encéfalo/patologia , Separação Celular , Citocinas/biossíntese , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Adjuvante de Freund/imunologia , Adjuvante de Freund/farmacologia , Humanos , Macrófagos/imunologia , Transtornos da Memória/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Monócitos/imunologia , Fragmentos de Peptídeos/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Receptor 2 Toll-Like/biossíntese , Receptor 2 Toll-Like/imunologia , Receptor 4 Toll-Like/biossíntese , Receptor 4 Toll-Like/imunologiaRESUMO
BACKGROUND: Alemtuzumab is an anti-CD52 antibody approved for the treatment of relapsing remitting multiple sclerosis (RRMS). The summary of product characteristics (SmPC) provides recommendations on the administration of alemtuzumab to prevent or reduce the risk of serious side effects associated with alemtuzumab infusion, including myocardial ischemia, hemorrhagic stroke, arterial dissection, and pulmonary alveolar hemorrhage. However, real-world implementation of alemtuzumab infusion management recommendations has not been previously assessed. METHODS: Here we provide a large-scale multi-center (in- and outpatient) observational study on alemtuzumab infusion management in daily clinical care in Germany (ALEMLL08025; INFUSE-MS; NIS-no. 364). Parameters of infusion management - including infusion administration, clinical and laboratory monitoring - were assessed, compared between study centers and the occurrence of infusion-associated reactions (IARs) was documented. Moreover, the TSQM and MSIS-29 questionnaires were used to quantify patient satisfaction and health-related quality of life. RESULTS: 140 RRMS patients were enrolled in this study. Alemtuzumab infusion regimes (treatment course 1 and 2) were comparable between infusion sites and in accordance with recommendations by the SmPC. Standardization of infusion management was associated with a satisfactory safety profile. IARs were usually mild, headache (13.6%), rash (10.7%), and pyrexia (6.4%) being the most common ones. TSQM and MSIS-29 scores denoted high patient satisfaction and health-related quality of life among RRMS patients treated with alemtuzumab. CONCLUSION: In conclusion, our results indicate that infusion management of alemtuzumab is highly standardized and in line with the SmPC. Alemtuzumab treatment and implementation of infusion management recommendations are associated with a satisfactory safety profile regarding the occurrence of IARs, a high patient satisfaction and health-related quality of life as important indicators for the quality of MS care.
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Esclerose Múltipla Recidivante-Remitente , Qualidade de Vida , Alemtuzumab/efeitos adversos , Alemanha , Humanos , Esclerose Múltipla Recidivante-Remitente/terapia , Satisfação do Paciente , Satisfação PessoalRESUMO
BACKGROUND AND AIMS: To investigate effectiveness and safety of teriflunomide (14 mg once daily) in association with age and pre-treatment in unselected MS patients. METHODS: Prespecified analysis of a non-interventional, prospective, real-world study in Germany. RESULTS: A total of 558 (49.5%) patients were above 45 years old, and 593 patients (52.6%) had been pre-treated within 6 months prior to teriflunomide. Baseline Expanded Disability Status Scale (EDSS) was higher with older age, with lower number of relapses. Relapse rate decreased in all age groups, and in both treatment-naïve (0.82 ± 0.73 at baseline; 0.25 ± 0.55 under teriflunomide) and pre-treated (from 0.48 ± 0.76; 0.22 ± 0.50) patients after 12 months compared with the year before teriflunomide initiation. EDSS remained stable in patients of all age groups as well as in therapy-naïve and pre-treated patients over 24 months. The percentage of patients with adverse events (AEs) ranged between 29.2% (age group >25-35) and 38.9% (age group >55-65), with an increased discontinuation rate (most commonly due to diarrhoea, alopecia and nausea) in the higher age groups. AE rates were lower in pre-treated compared with treatment-naïve patients. CONCLUSION: Overall, patients of all age groups including older patients, and irrespective of pre-treatment, benefit from teriflunomide treatment in routine clinical practice. REGISTRATION: BfArM public study database number 2075.
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INTRODUCTION: In patients with multiple sclerosis (MS), fatigue, depression, and physical disability are important determinants that negatively affect health-related quality of life (HRQoL). In studies about MS, HRQoL and treatment satisfaction are emerging endpoints representing the patients' perspective. However, the association of HRQoL and MS treatment satisfaction has not been evaluated so far. PURPOSE: Our objective was to evaluate the relationship of different dimensions of HRQoL and treatment satisfaction (effectiveness, side effects, convenience), and to assess which factors of treatment satisfaction, besides disease-related and sociodemographic explanatory factors, can best describe HRQoL. PATIENTS AND METHODS: We analyzed data from a cross-sectional, observational multicenter study in Germany (THEPA-MS, N=2990 eligible patients for first-line treatment). The instruments used were the SF-36 for HRQoL and the TSQM for treatment satisfaction. Correlation analyses, classification and regression trees and multivariate linear regression with the least absolute shrinkage and selection operator (LASSO) for global variable selection were used to analyze explanatory factors of HRQoL. RESULTS: The SF-36 physical summary score was 45.49 ±12.03 and mental component summary score 42.87 ±12.12, with currently untreated patients (N=250) reporting lower HRQoL than patients under first-line treatment (N=2740) (p<0.001). Physical disability (standardized beta (b)=0.408) was the strongest cross-sectional predictor for physical health, followed by employment status (b=0.163), age (b=0.159) and treatment satisfaction in terms of side effects (b=0.146) and effectiveness (b=0.137). For the mental summary health dimension, presence of a major depressive episode (b=0.234) had the greatest impact, followed by satisfaction with side effects (b=0.152) and effectiveness (b=0.131). CONCLUSION: Satisfaction with the effectiveness and side effects of treatment was part of the main independent explanatory variables for mental and physical HRQoL in patients with MS. To improve HRQoL, patients' needs and satisfaction measures may be integral part of disease management beyond treatment of physical disability, depression or fatigue.
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BACKGROUND: Teriflunomide is a once-daily oral immunomodulatory agent approved for the treatment of relapsing-remitting multiple sclerosis (MS). We aimed to obtain data on the effectiveness, tolerability, and subject satisfaction with teriflunomide (Aubagio®) under clinical practice conditions in unselected MS patients. METHODS: This work was a non-interventional, prospective, longitudinal, observational study in 307 sites in Germany. RESULTS: A total of 1128 patients were eligible for the efficacy analysis [67.5% female; mean age (± standard deviation) 44.9 ± 9.7 years, range 20-73 years]. Time since first MS symptoms was 10.6 ± 8.2 years, and time since MS diagnosis was 8.9 ± 7.6 years. Expanded Disability Status Scale (EDSS) score at inclusion was 2.3 ± 1.5 (70.4% with score < 3.5). The mean observation period was 16.3 ± 9.1 months. A total of 75.2% had received previous disease-modifying therapies (DMTs) at any time. Of these patients, 504 (44.7%) received no DMT within 6 months of study entry, 593 patients (52.6%) had DMT discontinued prior to study entry [glatiramer acetate in 10.6%, subcutaneous interferon-beta 1a (IFNß-1a) in 9.3%, intramuscular IFNß-1a or IFNß-1b in 6.6% each, azathioprine oral in 0.4%, other in 7.3%, last medication not known in 12.0%]. The mean annualized relapse rate decreased from 0.87 in the 24 months prior to study entry to 0.35 in the 24 months after study entry (n = 468; p ⩽ 0.001). EDSS and Fatigue Severity Scale remained stable. In patients who received previous MS treatments, Treatment Satisfaction Questionnaire (TSQM-9) values (maximum = 100), for the observation at 24 months improved by 8.1 points for effectiveness, 17.0 points for convenience, and 15.3 points for global satisfaction (p ⩽ 0.001 each, compared with study entry). In the safety cohort (n = 1139), the proportion of patients with adverse events (AEs) of any severity was 35.8%, and with serious events 13.0%. The most frequently reported AEs were diarrhea (n = 55), followed by MS relapse (n = 48), hair thinning (n = 38), and viral upper respiratory tract infection (n = 31). CONCLUSIONS: Relapse rate was halved during the observation period in comparison with the same time period before study entry. Patient satisfaction with teriflunomide was high in this real-world observation of patients, the majority of whom switched from other DMTs. The safety and tolerability profile of teriflunomide was similar to that reported in previous clinical trials.
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BACKGROUND: Improved clinical effectiveness and therefore positive modification of multiple sclerosis (MS) with basic therapy can be achieved by long-term regular intake of drugs as prescribed but investigations have shown that a high percentage of patients do not take their medications as prescribed. OBJECTIVES: We assessed the satisfaction and adherence of patients with MS with their current disease-modifying treatment under clinical practice conditions. We compared different facets of satisfaction as well as their internal relationship and identified predictors in an exploratory manner. METHODS: Therapy satisfaction in patients with relapsing-remitting multiple sclerosis (THEPA-MS) was a noninterventional, prospective cross-sectional study performed throughout Germany in 2013 and 2014, and included patients with clinically isolated syndrome or relapsing-remitting MS. We applied a standardized approach to document satisfaction and adherence by patient-reported outcomes (Treatment Satisfaction Questionnaire for Medication) as well as by physician ratings. RESULTS: Of 3312 patients with a mean age of 43.7 years, 73.3% were women and the mean level of disability according to the Expanded Disability Status Scale was 2.29; 13.3% did not receive any medication at the time of documentation, 21.3% received interferon ß1a intramuscularly, 20.7% had interferon ß1a subcutaneously, 17.0% had interferon ß1b subcutaneously and 23.7% had glatiramer acetate. Adherence rates varied between 60% (lifetime) and 96.5% (current medication). Differences between current medications were found for side effects and convenience scores but not for effectiveness, satisfaction and adherence. Higher global satisfaction and effectiveness were associated with fewer relapses, longer duration of medication, lower disability score and the absence of several side effects. CONCLUSION: In a connected model of patient satisfaction, effectiveness, side effects, convenience and adherence, patients' individual needs and concerns have to be addressed. Most differences were found with respect to side effects and convenience of treatment. Therefore, an improvement in these two domains seems to be the most promising proximate approach to elevate adherence levels.
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Regional changes in brain structure have been reported in patients with altered visceral sensitivity and chronic abdominal pain, such as in irritable bowel syndrome. It remains unknown whether structural brain changes are associated with visceral sensitivity. Therefore, we present the first study in healthy individuals to address whether interindividual variations in gray matter volume (GMV) in pain-relevant regions correlate with visceral sensitivity. In 92 healthy young adults (52 female), we assessed rectal sensory and pain thresholds and performed voxel-based morphometry (VBM) to compute linear regression models with visceral sensory and pain thresholds, respectively, as independent variable and GMV in a priori-defined regions of interest (ROIs) as dependent variable. All results were familywise error (FWE) corrected at a level of PFWE<.05 and covaried for age. The mean (±SEM) rectal thresholds were 14.78±0.46mm Hg for first sensation and 33.97±1.13mm Hg for pain, without evidence of sex differences. Lower rectal sensory threshold (ie, increased sensitivity) correlated significantly with reduced GMV in the thalamus, insula, posterior cingulate cortex, ventrolateral and orbitofrontal prefrontal cortices, amygdala, and basal ganglia (all PFWE<.05). Lower rectal pain threshold was associated with reduced GMV in the right thalamus (PFWE=.051). These are the first data supporting that increased visceral sensitivity correlates with decreased gray matter volume in pain-relevant brain regions. These findings support that alterations in brain morphology not only occur in clinical pain conditions but also occur according to normal interindividual variations in visceral sensitivity.
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Córtex Cerebral/patologia , Córtex Cerebral/fisiologia , Voluntários Saudáveis , Imageamento por Ressonância Magnética/métodos , Limiar da Dor/fisiologia , Dor Visceral/diagnóstico , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Tamanho do Órgão , Dor Visceral/fisiopatologia , Adulto JovemRESUMO
Acute peripheral inflammation with corresponding increases in peripheral cytokines affects neuropsychological functions and induces depression-like symptoms. However, possible effects of increased immune responses on social cognition remain unknown. Therefore, this study investigated the effects of experimentally induced acute inflammation on performance and neural responses during a social cognition task assessing Theory of Mind (ToM) ability. In this double-blind randomized crossover functional magnetic resonance imaging study, 18 healthy right-handed male volunteers received an injection of bacterial lipopolysaccharide (LPS; 0.4 ng/kg) or saline, respectively. Plasma levels of pro- and anti-inflammatory cytokines as well as mood ratings were analyzed together with brain activation during a validated ToM task (i.e. Reading the Mind in the Eyes Test). LPS administration induced pronounced transient increases in pro- (IL-6, TNF-α) and anti-inflammatory (IL-10, IL-1ra) cytokines as well as decreases in mood. Social cognition performance was not affected by acute inflammation. However, altered neural activity was observed during the ToM task after LPS administration, reflected by increased responses in the fusiform gyrus, temporo-parietal junction, superior temporal gyrus and precuneus. The increased task-related neural responses in the LPS condition may reflect a compensatory strategy or a greater social cognitive processing as a function of sickness.
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Encéfalo/fisiopatologia , Cognição/fisiologia , Endotoxemia/fisiopatologia , Neuroimunomodulação/fisiologia , Percepção Social , Teoria da Mente/fisiologia , Doença Aguda , Adulto , Afeto/fisiologia , Mapeamento Encefálico , Estudos Cross-Over , Citocinas/sangue , Método Duplo-Cego , Emoções/fisiologia , Expressão Facial , Voluntários Saudáveis , Humanos , Lipopolissacarídeos , Imageamento por Ressonância Magnética , Masculino , Distribuição Aleatória , Percepção Visual/fisiologiaRESUMO
Salivary α-amylase (sAA) is a digestive enzyme that plays also an important role in mucosal immunity. Secretion of the sAA is largely under the control of the autonomic nervous system and increases in sAA activity have repeatedly been observed in response to various stressors. The present study aimed at investigating whether and to what extent sAA activity levels are affected during systemic inflammation. Fourteen healthy male volunteers received intravenous injections of either bacterial endotoxin or placebo at two different occasions in a randomized and double-blinded manner. sAA activity was monitored over a period of 6h together with inflammatory markers, plasma norepinephrine (NE) and salivary cortisol levels, vital parameters, and state anxiety. Endotoxin administration elicited a transient inflammatory response reflected by increases in body temperature, whole blood cell counts, and circulating levels of interleukin (IL)-6. The immune changes were accompanied by a transient increase in sAA activity, elevations in salivary cortisol and plasma NE concentrations, as well as increases in heart rate and state anxiety. Although sAA and plasma NE responses showed distinct time courses, a significant positive correlation over the total observation period was found. Whether the observed sAA response is driven by an increase in sympathetic activity or more generally reflects inflammation induced changes in sympathetic-parasympathetic balance remains to be elucidated.
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Endotoxemia/fisiopatologia , Endotoxinas/toxicidade , Glândulas Salivares/metabolismo , alfa-Amilases Salivares/metabolismo , Adulto , Pressão Sanguínea/efeitos dos fármacos , Temperatura Corporal , Método Duplo-Cego , Endotoxemia/sangue , Endotoxemia/enzimologia , Frequência Cardíaca/efeitos dos fármacos , Humanos , Hidrocortisona/sangue , Interleucina-6/sangue , Contagem de Leucócitos , Masculino , Norepinefrina/sangue , Sistema Nervoso Parassimpático/fisiopatologia , Distribuição Aleatória , Glândulas Salivares/enzimologia , Sistema Nervoso Simpático/fisiopatologiaRESUMO
Clinical and experimental evidence document that inflammation and increased peripheral cytokine levels are associated with depression-like symptoms and neuropsychological disturbances in humans. However, it remains unclear whether and to what extent cognitive functions like memory and attention are affected by and related to the dose of the inflammatory stimulus. Thus, in a cross-over, double-blind, experimental approach, healthy male volunteers were administered with either placebo or bacterial lipopolysaccharide (LPS) at doses of 0.4 (nâ=â18) or 0.8 ng/kg of body weight (nâ=â16). Pro- and anti-inflammatory cytokines, norephinephrine and cortisol concentrations were analyzed before and 1, 1.75, 3, 4, 6, and 24 h after injection. In addition, changes in mood and anxiety levels were determined together with working memory (n-back task) and long term memory performance (recall of emotional and neutral pictures of the International Affective Picture System). Endotoxin administration caused a profound transient physiological response with dose-related elevations in body temperature and heart rate, increases in plasma interleukin (IL)-6, IL-10, tumor necrosis factor (TNF)-α and IL-1 receptor antagonist (IL-1ra), salivary and plasma cortisol, and plasma norepinephrine. These changes were accompanied by dose-related decreased mood and increased anxiety levels. LPS administration did not affect accuracy in working memory performance but improved reaction time in the high-dose LPS condition compared to the control conditon. In contrast, long-term memory performance was impaired selectively for emotional stimuli after administration of the lower but not of the higher dose of LPS. These data suggest the existence of at least two counter-acting mechanisms, one promoting and one inhibiting cognitive performance during acute systemic inflammation.