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1.
Breast Cancer Res ; 26(1): 87, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38816770

ABSTRACT

BACKGROUND: Despite progress understanding the mechanisms underlying tumor spread, metastasis remains a clinical challenge. We identified the choline-producing glycerophosphodiesterase, EDI3 and reported its association with metastasis-free survival in endometrial cancer. We also observed that silencing EDI3 slowed cell migration and other cancer-relevant phenotypes in vitro. Recent work demonstrated high EDI3 expression in ER-HER2+ breast cancer compared to the other molecular subtypes. Silencing EDI3 in ER-HER2+ cells significantly reduced cell survival in vitro and decreased tumor growth in vivo. However, a role for EDI3 in tumor metastasis in this breast cancer subtype was not explored. Therefore, in the present work we investigate whether silencing EDI3 in ER-HER2+ breast cancer cell lines alters phenotypes linked to metastasis in vitro, and metastasis formation in vivo using mouse models of experimental metastasis. METHODS: To inducibly silence EDI3, luciferase-expressing HCC1954 cells were transduced with lentiviral particles containing shRNA oligos targeting EDI3 under the control of doxycycline. The effect on cell migration, adhesion, colony formation and anoikis was determined in vitro, and significant findings were confirmed in a second ER-HER2+ cell line, SUM190PT. Doxycycline-induced HCC1954-luc shEDI3 cells were injected into the tail vein or peritoneum of immunodeficient mice to generate lung and peritoneal metastases, respectively and monitored using non-invasive bioluminescence imaging. Metabolite levels in cells and tumor tissue were analyzed using targeted mass spectrometry and MALDI mass spectrometry imaging (MALDI-MSI), respectively. RESULTS: Inducibly silencing EDI3 reduced cell adhesion and colony formation, as well as increased susceptibility to anoikis in HCC1954-luc cells, which was confirmed in SUM190PT cells. No influence on cell migration was observed. Reduced luminescence was seen in lungs and peritoneum of mice injected with cells expressing less EDI3 after tail vein and intraperitoneal injection, respectively, indicative of reduced metastasis. Importantly, mice injected with EDI3-silenced cells survived longer. Closer analysis of the peritoneal organs revealed that silencing EDI3 had no effect on metastatic organotropism but instead reduced metastatic burden. Finally, metabolic analyses revealed significant changes in choline and glycerophospholipid metabolites in cells and in pancreatic metastases in vivo. CONCLUSIONS: Reduced metastasis upon silencing supports EDI3's potential as a treatment target in metastasizing ER-HER2+ breast cancer.


Subject(s)
Breast Neoplasms , Receptor, ErbB-2 , Receptors, Estrogen , Animals , Female , Humans , Mice , Cell Line, Tumor , Receptor, ErbB-2/metabolism , Receptor, ErbB-2/genetics , Breast Neoplasms/pathology , Breast Neoplasms/genetics , Breast Neoplasms/metabolism , Receptors, Estrogen/metabolism , Disease Models, Animal , Cell Movement , Gene Knockdown Techniques , Tumor Burden , Neoplasm Metastasis , Lung Neoplasms/secondary , Lung Neoplasms/genetics , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Cell Proliferation
2.
Article in English | MEDLINE | ID: mdl-38700468

ABSTRACT

BACKGROUND: Activation of the vagus nerve mediates cardioprotection and attenuates myocardial ischemia/reperfusion (I/R) injury. In response to vagal activation, acetylcholine (ACh) is released from the intracardiac nervous system (ICNS) and activates intracellular cardioprotective signaling cascades. Recently, however, a non-neuronal cholinergic cardiac system (NNCCS) in cardiomyocytes has been described as an additional source of ACh. AIM: To investigate whether the NNCCS mediates cardioprotection in absence of vagal and ICNS activation. For that, we used a reductionist approach of isolated adult rat ventricular cardiomyocytes in absence of neuronal cells with hypoxic preconditioning (HPC) as protective stimulus. METHODS: Adult rat ventricular cardiomyocytes were isolated, absence of neuronal cells was confirmed, HPC was induced by 10/20 min hypoxia/reoxygenation (H/R) before subjection to 30/5 min H/R to simulate I/R injury. Cardiomyocyte viability was assessed by trypan blue staining. Intra- and extracellular ACh was quantified using liquid chromatography-coupled mass spectrometry at baseline, after HPC, after hypoxia, and after reoxygenation, respectively. In a subset of experiments, muscarinic/nicotinic ACh receptor (mAChR/nAChR) antagonists were added during HPC or during H/R. RESULTS: Cardiomyocyte viability at baseline (69±4%) was reduced by H/R (10±3%). With HPC cardiomyocyte viability was preserved after H/R (25±6%). Intra- and extracellular ACh increased during hypoxia, HPC further increased both intra- and extracellular ACh (from 0.9±0.7 to 1.5±1.0 nmol/mg; from 0.7±0.6 to 1.1±0.7 nmol/mg). Addition of mAChR and nAChR antagonists during HPC had no impact on HPC´s protection, however protection was abrogated when antagonists were added during H/R (cardiomyocyte viability after H/R: 23±5%; 13±4%). CONCLUSION: Activation of the NNCCS is involved in cardiomyocyte protection: HPC increases intra- and extracellular ACh during H/R, and m-/nAChRs are causally involved in HPC´s cardiomyocyte protection during H/R. The interplay between upstream ICNS activation and the NNCCS activation to myocardial cholinergic metabolism and cardioprotection needs to be investigated in future studies.

3.
Life (Basel) ; 14(2)2024 Jan 29.
Article in English | MEDLINE | ID: mdl-38398703

ABSTRACT

While several studies have shown associations between hearing disorders and congenital toxoplasmosis, the present study investigated the impact of chronic, latent Toxoplasma gondii (T. gondii) infection on hearing loss. We used a regression analysis to explore whether latent T. gondii infection modulates changes in hearing thresholds over an age range from 20 to 70 years. We analyzed audiometric data of 162 T. gondii IgG-positive and 430 T. gondii-negative participants, collected in the Dortmund Vital Study (DVS, ClinicalTrials.gov Identifier: NCT05155397), a prospective study on healthy cognitive aging. The regression analysis indicated that latent toxoplasmosis was associated with an accelerated development in hearing loss over the observed age range. Hearing loss was less frequent in IgG-positive than in IgG-negative participants up to the age of about 40 for a low (0.125-1 kHz)-frequency range. For high (2-8 kHz) frequencies, this pattern reversed for ages above 65 years. We discuss these findings on hearing function in the context of a recently proposed model, suggesting that latent toxoplasmosis can differentially affect brain functions across a lifespan.

4.
Cells ; 12(18)2023 09 21.
Article in English | MEDLINE | ID: mdl-37759553

ABSTRACT

Metabolic Dysfunction Associated Steatotic Liver Disease (MASLD) is the most common chronic liver disease in Western countries. It is becoming increasingly evident that peripheral organ-centered inflammatory diseases, including liver diseases, are linked with brain dysfunctions. Therefore, this study aims to unravel the effect of MASLD on brain histology, cognitive functions, and neurotransmitters. For this purpose, mice fed for 48 weeks on standard (SD) or Western diet (WD) were evaluated by behavioral tests, followed by sacrifice and analysis of the liver-brain axis including histopathology, immunohistochemistry, and biochemical analyses. Histological analysis of the liver showed features of Metabolic Dysfunction-Associated Steatohepatitis (MASH) in the WD-fed mice including lipid droplet accumulation, inflammation, and fibrosis. This was accompanied by an elevation of transaminase and alkaline phosphatase activities, increase in inflammatory cytokine and bile acid concentrations, as well as altered amino acid concentrations in the blood. Interestingly, compromised blood capillary morphology coupled with astrogliosis and microgliosis were observed in brain hippocampus of the WD mice, indicating neuroinflammation or a disrupted neurovascular unit. Moreover, attention was impaired in WD-fed mice along with the observations of impaired motor activity and balance, enhanced anxiety, and stereotyped head-twitch response (HTR) behaviors. Analysis of neurotransmitters and modulators including dopamine, serotonin, GABA, glutamate, and acetylcholine showed region-specific dysregulation in the brain of the WD-fed mice. In conclusion, the induction of MASH in mice is accompanied by the alteration of cellular morphology and neurotransmitter expression in the brain, associated with compromised cognitive functions.


Subject(s)
Diet, Western , Fatty Liver , Animals , Mice , Diet, Western/adverse effects , Cognition , Brain
5.
EXCLI J ; 22: 867-879, 2023.
Article in English | MEDLINE | ID: mdl-37720238

ABSTRACT

Urinary bladder cancer, a smoking and occupation related disease, was subject of several genome-wide association studies (GWAS). However, studies on the course of the disease based on GWAS findings differentiating between muscle invasive bladder cancer (MIBC) and non-muscle invasive bladder cancer (NMIBC) are rare. Thus we investigated 4 single nucleotide polymorphisms (SNPs) detected in GWAS, related to the genes coding for TACC3 (transforming, acidic coiled-coil containing protein 3), for FGFR3 (fibroblast growth factor receptor 3), for PSCA (prostate stem cell antigen) and the genes coding for CBX6 (chromobox homolog 6) and APOBEC3A (apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like 3A). This study is based on 712 bladder cancer patients and 875 controls from 3 different case control studies in Germany. The 4 SNPs of interest (PSCA rs2294008 and rs2978974, FGFR3-TACC3 rs798766, and CBX6-APOBEC3A rs1014971) were determined by real-time polymerase chain reaction. The distribution of the 4 SNPs does not vary significantly between cases and controls in the entire study group and in the 3 local subgroups, including two former highly industrialized areas and a region without such history. Also, no significant differences in the bladder cancer subgroups of MIBC and NMIBC were observed. The 4 investigated SNPs do not noticeably contribute differently to the bladder cancer risk for the bladder cancer subgroups of MIBC and NMIBC.

7.
JMIR Form Res ; 7: e40818, 2023 May 19.
Article in English | MEDLINE | ID: mdl-37204831

ABSTRACT

BACKGROUND: As employees age, their physical and mental abilities decline and work ability decreases, enhancing the risk for long-term sick leave or even premature retirement. However, the relative impact of biological and environmental determinants on work ability with increasing age is poorly understood in terms of their complexity. OBJECTIVE: Previous research has shown relationships between work ability and job and individual resources, as well as specific demographic and lifestyle-related variables. However, other potentially important predictors of work ability remain unexplored, such as personality traits and biological determinants, including cardiovascular, metabolic, immunological, and cognitive abilities or psychosocial factors. Our aim was to systematically evaluate a wide range of factors to extract the most crucial predictors of low and high work ability across the working life span. METHODS: As part of the Dortmund Vital Study, 494 participants from different occupational sectors, aged between 20 and 69 years, completed the Work Ability Index (WAI) assessing employee's mental and physical resources. A total of 30 sociodemographic variables were grouped into 4 categories (social relationships, nutrition and stimulants, education and lifestyle, and work related), and 80 biological and environmental variables were grouped into 8 domains (anthropometric, cardiovascular, metabolic, immunologic, personality, cognitive, stress related, and quality of life) and have been related to the WAI. RESULTS: Using the analyses, we extracted important sociodemographic factors influencing work ability, such as education, social activities, or sleep quality, and identified age-dependent and age-independent determinants of work ability. Regression models explained up to 52% of the WAI variance. Negative predictors of work ability were chronological and immunological age, immunological inefficiency, BMI, neuroticism, psychosocial stress, emotional exhaustion, demands from work, daily cognitive failures, subclinical depression, and burnout symptoms. Positive predictors were maximum heart rate during ergometry, normal blood pressure, hemoglobin and monocyte concentration, weekly physical activity, commitment to the company, pressure to succeed, and good quality of life. CONCLUSIONS: The identified biological and environmental risk factors allowed us to evaluate work ability in its complexity. Policy makers, employers, and occupational safety and health personnel should consider the modifiable risk factors we identified to promote healthy aging at work through focused physical, dietary, cognitive, and stress-reduced preventive programs, in addition to well-balanced working conditions. This may also increase the quality of life, commitment to the job, and motivation to succeed, which are important factors to maintain or even enhance work ability in the aging workforce and to prevent early retirement. TRIAL REGISTRATION: ClinicalTrials.gov NCT05155397; https://clinicaltrials.gov/ct2/show/NCT05155397. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.2196/32352.

8.
Neuroimmunomodulation ; 30(1): 81-92, 2023.
Article in English | MEDLINE | ID: mdl-36917961

ABSTRACT

INTRODUCTION: Excessive stress is increasingly recognized as an important trigger of many diseases prevalent in modern societies, and monitoring such stress-related effects could aid prevention. The measurement of salivary markers of inflammation is emerging as a promising tool to non-invasively quantify stress' effects on immune processes in everyday life and thereby detect early aberrations before the manifestation of serious health problems. However, more laboratory-controlled research is needed in order to establish the timescale and determinants of salivary cytokine responses to acute stress. METHODS: We repeatedly exposed participants to Cold Pressor Stress Test (CPT) or a control procedure and measured a wide array of salivary cytokines as well as subjective, cardiovascular, and cortisol stress reactions. CPT exposure was repeated every 15 min, 3 times in total, with a duration of 3 min each. Saliva was sampled immediately after the first two exposures as well as in 15-min intervals until 60 min after the onset of the first intervention. RESULTS: We found that many cytokines were detectable in saliva. Specific stress effects were limited to IL-8 and IL-6, however, which decreased immediately or 15 min after stress onset, respectively. Moreover, IL-8 was negatively correlated to cortisol output in the stress but not in the control group. Significant increases were also observed in salivary TNFα and IFNγ; however, these effects were similar under both stress and control conditions. DISCUSSION: Our results show that particular salivary cytokines may be sensitive to immediate effects of acute CPT-induced stress and also highlight the importance of employing control procedures to discern stress effects from unrelated variations in salivary cytokines.


Subject(s)
Cytokines , Hydrocortisone , Humans , Interleukin-8 , Stress, Psychological , Saliva , Hypothalamo-Hypophyseal System
9.
J Exp Clin Cancer Res ; 42(1): 25, 2023 Jan 20.
Article in English | MEDLINE | ID: mdl-36670508

ABSTRACT

BACKGROUND: Intrinsic or acquired resistance to HER2-targeted therapy is often a problem when small molecule tyrosine kinase inhibitors or antibodies are used to treat patients with HER2 positive breast cancer. Therefore, the identification of new targets and therapies for this patient group is warranted. Activated choline metabolism, characterized by elevated levels of choline-containing compounds, has been previously reported in breast cancer. The glycerophosphodiesterase EDI3 (GPCPD1), which hydrolyses glycerophosphocholine to choline and glycerol-3-phosphate, directly influences choline and phospholipid metabolism, and has been linked to cancer-relevant phenotypes in vitro. While the importance of choline metabolism has been addressed in breast cancer, the role of EDI3 in this cancer type has not been explored. METHODS: EDI3 mRNA and protein expression in human breast cancer tissue were investigated using publicly-available Affymetrix gene expression microarray datasets (n = 540) and with immunohistochemistry on a tissue microarray (n = 265), respectively. A panel of breast cancer cell lines of different molecular subtypes were used to investigate expression and activity of EDI3 in vitro. To determine whether EDI3 expression is regulated by HER2 signalling, the effect of pharmacological inhibition and siRNA silencing of HER2, as well as the influence of inhibiting key components of signalling cascades downstream of HER2 were studied. Finally, the influence of silencing and pharmacologically inhibiting EDI3 on viability was investigated in vitro and on tumour growth in vivo. RESULTS: In the present study, we show that EDI3 expression is highest in ER-HER2 + human breast tumours, and both expression and activity were also highest in ER-HER2 + breast cancer cell lines. Silencing HER2 using siRNA, as well as inhibiting HER2 signalling with lapatinib decreased EDI3 expression. Pathways downstream of PI3K/Akt/mTOR and GSK3ß, and transcription factors, including HIF1α, CREB and STAT3 were identified as relevant in regulating EDI3 expression. Silencing EDI3 preferentially decreased cell viability in the ER-HER2 + cells. Furthermore, silencing or pharmacologically inhibiting EDI3 using dipyridamole in ER-HER2 + cells resistant to HER2-targeted therapy decreased cell viability in vitro and tumour growth in vivo. CONCLUSIONS: Our results indicate that EDI3 may be a potential novel therapeutic target in patients with HER2-targeted therapy-resistant ER-HER2 + breast cancer that should be further explored.


Subject(s)
Breast Neoplasms , Humans , Female , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Phosphatidylinositol 3-Kinases , Cell Line, Tumor , Choline/metabolism , Choline/therapeutic use , RNA, Small Interfering , Receptor, ErbB-2/metabolism , Drug Resistance, Neoplasm/genetics , Phospholipases/genetics
10.
Elife ; 112022 06 06.
Article in English | MEDLINE | ID: mdl-35666097

ABSTRACT

Sleep strongly affects synaptic strength, making it critical for cognition, especially learning and memory formation. Whether and how sleep deprivation modulates human brain physiology and cognition is not well understood. Here we examined how overnight sleep deprivation vs overnight sufficient sleep affects (a) cortical excitability, measured by transcranial magnetic stimulation, (b) inducibility of long-term potentiation (LTP)- and long-term depression (LTD)-like plasticity via transcranial direct current stimulation (tDCS), and (c) learning, memory, and attention. The results suggest that sleep deprivation upscales cortical excitability due to enhanced glutamate-related cortical facilitation and decreases and/or reverses GABAergic cortical inhibition. Furthermore, tDCS-induced LTP-like plasticity (anodal) abolishes while the inhibitory LTD-like plasticity (cathodal) converts to excitatory LTP-like plasticity under sleep deprivation. This is associated with increased EEG theta oscillations due to sleep pressure. Finally, we show that learning and memory formation, behavioral counterparts of plasticity, and working memory and attention, which rely on cortical excitability, are impaired during sleep deprivation. Our data indicate that upscaled brain excitability and altered plasticity, due to sleep deprivation, are associated with impaired cognitive performance. Besides showing how brain physiology and cognition undergo changes (from neurophysiology to higher-order cognition) under sleep pressure, the findings have implications for variability and optimal application of noninvasive brain stimulation.


Subject(s)
Motor Cortex , Transcranial Direct Current Stimulation , Brain , Cognition , Evoked Potentials, Motor/physiology , Humans , Motor Cortex/physiology , Neuronal Plasticity/physiology , Sleep , Sleep Deprivation , Transcranial Direct Current Stimulation/methods , Transcranial Magnetic Stimulation
11.
Cells ; 11(10)2022 05 11.
Article in English | MEDLINE | ID: mdl-35626646

ABSTRACT

Rheumatoid arthritis (RA) is associated with systemic osteoporosis, which leads to severe disability and low quality of life. Current therapies target osteoclasts to reduce bone degradation, but more treatment options would be required to promote bone protection by acting directly on osteoblasts (OB). Recently, the local production of dopamine in inflamed joints of RA has been observed. Thus, in this project, we aimed to determine the implication of the neurotransmitter dopamine in the bone formation process in RA. Dopamine receptors (DR) in the human bone tissue of RA or osteoarthritis (OA) patients were examined by immunohistochemistry. DR in isolated human osteoblasts (OB) was analyzed by flow cytometry, and dopamine content was evaluated by ELISA. Osteoclasts (OC) were differentiated from the PBMCs of healthy controls (HC) and RA patients. Isolated cells were treated with specific dopamine agonists. The effect of dopamine on mineralization was evaluated by Alizarin red staining. Cytokine release in supernatants was measured by ELISA. Osteoclastogenesis was evaluated with TRAP staining. OC markers were analyzed via real-time PCR and bone resorption via staining of resorption pits with toluidine blue. All DR were observed in bone tissue, especially in the bone remodeling area. Isolated OB maintained DR expression, which allowed their study in vitro. Isolated OB expressed tyrosine hydroxylase, the rate-limiting enzyme for dopamine production, and contained dopamine. The activation of D2-like DR significantly increased bone mineralization in RA osteoblasts and increased osteoclastogenesis but did not alter the expression of OC markers nor bone resorption. DR were found in the bone remodeling area of human bone tissue and dopamine can be produced by osteoblasts themselves, thus suggesting a local autocrine/paracrine pathway of dopamine in the bone. D2-like DRs are responsible for bone mineralization in osteoblasts from RA patients without an increase in bone resorption, thus suggesting the D2-like DR pathway as a possible future therapeutic target to counteract bone resorption in arthritis.


Subject(s)
Arthritis, Rheumatoid , Bone Resorption , Arthritis, Rheumatoid/drug therapy , Arthritis, Rheumatoid/metabolism , Dopamine , Humans , Osteoblasts/metabolism , Osteogenesis , Quality of Life , Receptors, Dopamine
12.
Sci Rep ; 12(1): 5985, 2022 04 08.
Article in English | MEDLINE | ID: mdl-35396380

ABSTRACT

Rheumatoid arthritis (RA) is a chronic rheumatic disease with a clear sex-bias. Recent data indicated a role for dopamine in RA pathogenesis, while dopaminergic pathways can be modulated by estrogens. As defined mechanism of action of dopamine on B cell function in RA are unclear, we aimed to elucidate this, with special focus on sex-differences. Healthy controls (HC, n = 64) and RA patients (n = 61) were recruited. Expression of D1-D5 dopamine receptors (DRs) was investigated by flow cytometry on peripheral blood mononuclear cells (PBMCs). D1-like DRs were stimulated in vitro to assess effects on B cell activation and proliferation. Secretion of cytokines and dopamine content were measured by ELISA. All DRs were expressed on PBMCs of HC and RA patients. Dopamine content in PBMCs, and frequency of D1DR expressing B cells were significantly higher in RA females (p < 0.001). Expression of D1DR on RA B cells correlated positively with disease duration and severity only in women. Combined B cell and D1-like DR stimulation induced higher IL-8 and CCL-3 secretion from PBMCs of female RA patients compared to HC. These results indicate sex-specific differences in dopaminergic pathway in RA, with a proinflammatory feature of the D1DR pathway in women.


Subject(s)
Arthritis, Rheumatoid , B-Lymphocytes , Receptors, Dopamine , Arthritis, Rheumatoid/pathology , B-Lymphocytes/metabolism , Cytokines/metabolism , Dopamine/metabolism , Female , Humans , Leukocytes, Mononuclear/metabolism , Male , Receptors, Dopamine/metabolism , Receptors, Dopamine D1
13.
JMIR Res Protoc ; 11(3): e32352, 2022 Mar 14.
Article in English | MEDLINE | ID: mdl-35285810

ABSTRACT

BACKGROUND: Previous research revealed several biological and environmental factors modulating cognitive functioning over a human's lifespan. However, the relationships and interactions between biological factors (eg, genetic polymorphisms, immunological parameters, metabolic products, or infectious diseases) and environmental factors (eg, lifestyle, physical activity, nutrition, and work type or stress at work) as well as their impact on cognitive functions across the lifespan are still poorly understood with respect to their complexity. OBJECTIVE: The goal of the Dortmund Vital Study is to validate previous hypotheses as well as generate and validate new hypotheses about the relationships among aging, working conditions, genetic makeup, stress, metabolic functions, the cardiovascular system, the immune system, and mental performance over the human lifespan with a focus on healthy working adults. The Dortmund Vital Study is a multidisciplinary study involving the Departments of Ergonomics, Immunology, Psychology and Neurosciences, and Toxicology at the Leibniz Research Centre for Working Environment and Human Factors at the Technical University of Dortmund (IfADo) in Germany, as well as several national and international partners. METHODS: The Dortmund Vital Study is designed as a combined cross-sectional and longitudinal study. Approximately 600 healthy subjects aged between 20 and 70 years will participate. A wide range of demographic, psychological, behavioral, sensory, cardiovascular, immunological, and biochemical data, a comprehensive electroencephalography (EEG)-based cognitive test battery as well as structural and functional magnetic resonance imaging (MRI) have been included in the study. RESULTS: The study was approved by the Ethics Committee of IfADo in October 2015. The baseline testing was conducted between 2016 and 2021 and will be repeated every 5 years (3 follow-up measures until 2035). As of March 2020 (until the outbreak of the COVID-19 pandemic), 593 participants have been enrolled. Some results from the cross-sectional part of the study were already published, further results will be published soon. Longitudinal data will be analyzed and published by 2025. CONCLUSIONS: We anticipate that the study will shed light on sources of interindividual differences in the alterations of cognitive functioning with increasing age and reveal biological and lifestyle markers contributing to work ability, longevity, and healthy aging on the one hand, and to risk factors for cognitive decline, mild cognitive impairment, or even dementia on the other hand. TRIAL REGISTRATION: ClinicalTrials.gov NCT05155397; https://clinicaltrials.gov/ct2/show/NCT05155397. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/32352.

14.
Chem Biol Interact ; 351: 109728, 2022 Jan 05.
Article in English | MEDLINE | ID: mdl-34717914

ABSTRACT

An in vitro/in silico method that determines the risk of human drug induced liver injury in relation to oral doses and blood concentrations of drugs was recently introduced. This method utilizes information on the maximal blood concentration (Cmax) for a specific dose of a test compound, which can be estimated using physiologically-based pharmacokinetic modelling, and a cytotoxicity test in cultured human hepatocytes. In the present study, we analyzed if the addition of an assay that measures the inhibition of bile acid export carriers, like BSEP and/or MRP2, to the existing method improves the differentiation of hepatotoxic and non-hepatotoxic compounds. Therefore, an export assay for 5-chloromethylfluorescein diacetate (CMFDA) was established. We tested 36 compounds in a concentration-dependent manner for which the risk of hepatotoxicity for specific oral doses and the capacity to inhibit hepatocyte export carriers are known. Compared to the CTB cytotoxicity test, substantially lower EC10 values were obtained using the CMFDA assay for several known BSEP and/or MRP2 inhibitors. To quantify if the addition of the CMFDA assay to our test system improves the overall separation of hepatotoxic from non-hepatotoxic compounds, the toxicity separation index (TSI) was calculated. We obtained a better TSI using the lower alert concentration from either the CMFDA or the CTB test (TSI: 0.886) compared to considering the CTB test alone (TSI: 0.775). In conclusion, the data show that integration of the CMFDA assay with an in vitro test battery improves the differentiation of hepatotoxic and non-hepatotoxic compounds in a set of compounds that includes bile acid export carrier inhibitors.


Subject(s)
Cytotoxins/toxicity , Hepatocytes/drug effects , Toxicity Tests/methods , ATP Binding Cassette Transporter, Subfamily B, Member 11/antagonists & inhibitors , ATP Binding Cassette Transporter, Subfamily B, Member 11/metabolism , Cell Culture Techniques/methods , Cells, Cultured , Chemical and Drug Induced Liver Injury , Fluoresceins/metabolism , Humans , Mitochondria/drug effects , Multidrug Resistance-Associated Protein 2/antagonists & inhibitors , Multidrug Resistance-Associated Protein 2/metabolism
15.
Hepatol Commun ; 6(1): 161-177, 2022 01.
Article in English | MEDLINE | ID: mdl-34558834

ABSTRACT

Mouse models are frequently used to study chronic liver diseases (CLDs). To assess their translational relevance, we quantified the similarity of commonly used mouse models to human CLDs based on transcriptome data. Gene-expression data from 372 patients were compared with data from acute and chronic mouse models consisting of 227 mice, and additionally to nine published gene sets of chronic mouse models. Genes consistently altered in humans and mice were mapped to liver cell types based on single-cell RNA-sequencing data and validated by immunostaining. Considering the top differentially expressed genes, the similarity between humans and mice varied among the mouse models and depended on the period of damage induction. The highest recall (0.4) and precision (0.33) were observed for the model with 12-months damage induction by CCl4 and by a Western diet, respectively. Genes consistently up-regulated between the chronic CCl4 model and human CLDs were enriched in inflammatory and developmental processes, and mostly mapped to cholangiocytes, macrophages, and endothelial and mesenchymal cells. Down-regulated genes were enriched in metabolic processes and mapped to hepatocytes. Immunostaining confirmed the regulation of selected genes and their cell type specificity. Genes that were up-regulated in both acute and chronic models showed higher recall and precision with respect to human CLDs than exclusively acute or chronic genes. Conclusion: Similarly regulated genes in human and mouse CLDs were identified. Despite major interspecies differences, mouse models detected 40% of the genes significantly altered in human CLD. The translational relevance of individual genes can be assessed at https://saezlab.shinyapps.io/liverdiseaseatlas/.


Subject(s)
Disease Models, Animal , Gene Expression Profiling , Liver Diseases/genetics , Transcriptome , Animals , Chronic Disease , Down-Regulation , Humans , Mice , Species Specificity , Up-Regulation
16.
Toxins (Basel) ; 15(1)2022 12 30.
Article in English | MEDLINE | ID: mdl-36668846

ABSTRACT

Citrinin (CIT), a mycotoxin known to exert nephrotoxicity, is a contaminant in food and feed. Since CIT contamination is not regularly analyzed, data on its occurrence and especially levels in food commodities are insufficient for conducting a conventional exposure assessment. Yet, human biomonitoring, i.e., an analysis of CIT and its metabolite dihydrocitrinone (DH-CIT) in urine samples allows to estimate exposure. This study investigated CIT exposure in young (2-14 years) and adult (24-61 years) residents of three federal states in Germany. A total of 179 urine samples from children and 142 from adults were collected and analyzed by a targeted LC-MS/MS based method for presence of CIT and DH-CIT. At least one of the biomarkers was detected and quantified in all urines, which indicated a widespread dietary exposure to the mycotoxin in Germany. Interestingly, the biomarker concentrations of CITtotal (sum of CIT and DH-CIT) were higher in children's urine (range 0.05-7.62 ng/mL; median of 0.54 ng/mL) than in urines from adults (range 0.04-3.5 ng/mL; median 0.3 ng/mL). The biomarker levels (CITtotal) of individual urines served to calculate the probable daily CIT intake, for comparison to a value of 0.2 µg/kg bw/day defined as 'level of no concern for nephrotoxicity' by the European Food Safety Authority. The median exposure of German adults was 0.013 µg/kg b.w., with only one urine donor exceeding this provisional tolerable daily intake (pTDI) for CIT. The median exposure of children was 0.05 µg/kg bw per day (i.e., 25% of the pTDI); however, CIT exposure in 12 individuals (6.3% of our study group) exceeded the limit value, with a maximum intake of 0.46 µg/kg b.w. per day. In conclusion, these results show evidence for non-negligible exposure to CIT in some individuals in Germany, mainly in children. Therefore, further biomonitoring studies and investigations aimed to identify the major sources of CIT exposure in food commodities are required.


Subject(s)
Citrinin , Humans , Child , Citrinin/analysis , Chromatography, Liquid , Tandem Mass Spectrometry , Biomarkers/urine , Germany , Food Contamination/analysis
17.
Cell Rep ; 36(8): 109526, 2021 08 24.
Article in English | MEDLINE | ID: mdl-34433051

ABSTRACT

Epigenetic modifications (e.g. DNA methylation) in NAFLD and their contribution to disease progression and extrahepatic complications are poorly explored. Here, we use an integrated epigenome and transcriptome analysis of mouse NAFLD hepatocytes and identify alterations in glyoxylate metabolism, a pathway relevant in kidney damage via oxalate release-a harmful waste product and kidney stone-promoting factor. Downregulation and hypermethylation of alanine-glyoxylate aminotransferase (Agxt), which detoxifies glyoxylate, preventing excessive oxalate accumulation, is accompanied by increased oxalate formation after metabolism of the precursor hydroxyproline. Viral-mediated Agxt transfer or inhibiting hydroxyproline catabolism rescues excessive oxalate release. In human steatotic hepatocytes, AGXT is also downregulated and hypermethylated, and in NAFLD adolescents, steatosis severity correlates with urinary oxalate excretion. Thus, this work identifies a reduced capacity of the steatotic liver to detoxify glyoxylate, triggering elevated oxalate, and provides a mechanistic explanation for the increased risk of kidney stones and chronic kidney disease in NAFLD patients.


Subject(s)
Epigenome , Glyoxylates/metabolism , Hepatocytes/metabolism , Hyperoxaluria/metabolism , Non-alcoholic Fatty Liver Disease/metabolism , Transcriptome , Animals , Epigenomics , Gene Expression Profiling , Humans , Hyperoxaluria/genetics , Male , Mice , Mice, Obese , Non-alcoholic Fatty Liver Disease/genetics , Risk Factors
18.
Brain ; 144(4): 1214-1229, 2021 05 07.
Article in English | MEDLINE | ID: mdl-33871026

ABSTRACT

Knowledge about converging disease mechanisms in the heterogeneous syndrome amyotrophic lateral sclerosis (ALS) is rare, but may lead to therapies effective in most ALS cases. Previously, we identified serum microRNAs downregulated in familial ALS, the majority of sporadic ALS patients, but also in presymptomatic mutation carriers. A 5-nucleotide sequence motif (GDCGG; D = G, A or U) was strongly enriched in these ALS-related microRNAs. We hypothesized that deregulation of protein(s) binding predominantly to this consensus motif was responsible for the ALS-linked microRNA fingerprint. Using microRNA pull-down assays combined with mass spectrometry followed by extensive biochemical validation, all members of the fragile X protein family, FMR1, FXR1 and FXR2, were identified to directly and predominantly interact with GDCGG microRNAs through their structurally disordered RGG/RG domains. Preferential association of this protein family with ALS-related microRNAs was confirmed by in vitro binding studies on a transcriptome-wide scale. Immunohistochemistry of lumbar spinal cord revealed aberrant expression level and aggregation of FXR1 and FXR2 in C9orf72- and FUS-linked familial ALS, but also patients with sporadic ALS. Further analysis of ALS autopsies and induced pluripotent stem cell-derived motor neurons with FUS mutations showed co-aggregation of FXR1 with FUS. Hence, our translational approach was able to take advantage of blood microRNAs to reveal CNS pathology, and suggests an involvement of the fragile X-related proteins in familial and sporadic ALS already at a presymptomatic stage. The findings may uncover disease mechanisms relevant to many patients with ALS. They furthermore underscore the systemic, extra-CNS aspect of ALS.


Subject(s)
Amyotrophic Lateral Sclerosis/metabolism , Fragile X Mental Retardation Protein/metabolism , MicroRNAs/blood , MicroRNAs/genetics , RNA-Binding Proteins/metabolism , Amyotrophic Lateral Sclerosis/genetics , C9orf72 Protein/genetics , Humans , RNA-Binding Protein FUS/genetics
19.
Psychoneuroendocrinology ; 124: 105100, 2021 02.
Article in English | MEDLINE | ID: mdl-33338971

ABSTRACT

BACKGROUND: Activity of the two major stress systems, the hypothalamic-pituitary-adrenal (HPA) and the sympathetic-adrenal-medullary (SAM) axis, has already been shown to be modulated by different compounds that bind to the central benzodiazepine receptor. Less is known about ligands that modulate the peripheral benzodiazepine receptor - meanwhile known as the translocator protein 18 kDa (TSPO) - which constitute promising candidates in the search of novel anxiolytics. To close this gap, the present study compared the effects of the benzodiazepine alprazolam and the TSPO ligand etifoxine on responses of the HPA and SAM axes to the Trier Social Stress Test, a standardized paradigm to induce acute psychosocial stress in humans, performed in Virtual Reality (VR-TSST). METHODS: Sixty healthy males, aged between 18 and 55 years, were randomly assigned to receive either a daily dose of 1.5 mg alprazolam, 150 mg etifoxine, or placebo over five days. On the last day of intake, they were exposed to the VR-TSST. We assessed changes of salivary cortisol, allopregnanolone, (nor-) epinephrine in serum, TSPO expression in platelets as well as heart rate (HR), skin conductance level (SCL) and self-reports in response to the stress task. Repeated measures ANOVAs were conducted to examine treatment effects on these stress response variables during the course of VR-TSST. RESULTS: The response of salivary cortisol to the VR-TSST was significantly blunted in participants pre-treated with alprazolam but was not affected by etifoxine. While levels of allopregnanolone, epinephrine and norepinephrine increased in response to stress, TSPO expression decreased. None of those endocrine stress markers was affected by the active treatments, whereas TSPO expression increased after etifoxine administration over all study days. There were no effects of the two anxiolytics on HR, SCL or any self-report measurement. CONCLUSION: The current study confirmed the attenuating effects of benzodiazepines on stress-induced HPA axis activity but did not reveal a comparable effect of the TSPO ligand etifoxine. The long-term consequences of a pharmacologically blunted response of the HPA axis to an acute stressor should be further elucidated. Due to the missing effects of etifoxine on stress-related parameters in our sample of healthy subjects, it might be concluded that the therapeutic effects of this TSPO ligand are restricted to stronger or pathological stress responses, respectively.


Subject(s)
Alprazolam/pharmacology , Anti-Anxiety Agents , Virtual Reality , Adolescent , Adult , Anti-Anxiety Agents/pharmacology , Benzodiazepines , Epinephrine , Humans , Hydrocortisone , Hypothalamo-Hypophyseal System , Ligands , Male , Middle Aged , Oxazines , Pituitary-Adrenal System , Pregnanolone , Psychological Tests , Receptors, GABA , Receptors, GABA-A , Saliva , Stress, Psychological , Young Adult
20.
Sci Rep ; 10(1): 7876, 2020 05 12.
Article in English | MEDLINE | ID: mdl-32398793

ABSTRACT

Diffuse large B-cell lymphoma (DLBCL) is commonly classified by gene expression profiling according to its cell of origin (COO) into activated B-cell (ABC)-like and germinal center B-cell (GCB)-like subgroups. Here we report the application of label-free nano-liquid chromatography - Sequential Window Acquisition of all THeoretical fragment-ion spectra - mass spectrometry (nanoLC-SWATH-MS) to the COO classification of DLBCL in formalin-fixed paraffin-embedded (FFPE) tissue. To generate a protein signature capable of predicting Affymetrix-based GCB scores, the summed log2-transformed fragment ion intensities of 780 proteins quantified in a training set of 42 DLBCL cases were used as independent variables in a penalized zero-sum elastic net regression model with variable selection. The eight-protein signature obtained showed an excellent correlation (r = 0.873) between predicted and true GCB scores and yielded only 9 (21.4%) minor discrepancies between the three classifications: ABC, GCB, and unclassified. The robustness of the model was validated successfully in two independent cohorts of 42 and 31 DLBCL cases, the latter cohort comprising only patients aged >75 years, with Pearson correlation coefficients of 0.846 and 0.815, respectively, between predicted and NanoString nCounter based GCB scores. We further show that the 8-protein signature is directly transferable to both a triple quadrupole and a Q Exactive quadrupole-Orbitrap mass spectrometer, thus obviating the need for proprietary instrumentation and reagents. This method may therefore be used for robust and competitive classification of DLBCLs on the protein level.


Subject(s)
Cell Lineage/genetics , Gene Expression Profiling/methods , Lymphoma, Large B-Cell, Diffuse/genetics , Proteins/metabolism , Proteome/metabolism , Proteomics/methods , B-Lymphocytes/metabolism , B-Lymphocytes/pathology , Chromatography, Liquid/methods , Formaldehyde , Germinal Center/metabolism , Humans , Lymphoma, Large B-Cell, Diffuse/classification , Lymphoma, Large B-Cell, Diffuse/metabolism , Mass Spectrometry/methods , Nanotechnology/methods , Paraffin Embedding/methods , Proteins/genetics , Proteome/genetics , Tissue Fixation/methods
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