64 research outputs found
Cannabidiol attenuates inflammatory impairment of intestinal cells expanding biomaterial-based therapeutic approaches
Cannabis-based biomaterials have the potential to deliver anti-inflammatory therapeutics specifically to desired cells, tissues, and organs, enhancing drug delivery and the effectiveness of anti-inflammatory treatment while minimizing toxicity. As a major component of Cannabis, Cannabidiol (CBD) has gained major attention in recent years because of its potential therapeutic properties, e.g., for restoring a disturbed barrier resulting from inflammatory conditions. The aim of this study was to test the hypothesis that CBD has beneficial effects under normal and inflammatory conditions in the established non-transformed intestinal epithelial cell model IPEC-J2. CBD induced a significant increase in transepithelial electrical resistance (TER) values and a decrease in the paracellular permeability of [³H]-D-Mannitol, indicating a strengthening effect on the barrier. Under inflammatory conditions induced by tumor necrosis factor alpha (TNFα), CBD stabilized the TER and mitigated the increase in paracellular permeability. Additionally, CBD prevented the barrier-disrupting effects of TNFα on the distribution and localization of sealing TJ proteins. CBD also affected the expression of TNF receptors. These findings demonstrate the potential of CBD as a component of Cannabis-based biomaterials used in the development of novel therapeutic approaches against inflammatory pathogenesis
Concerted action of berberine in the porcine intestinal epithelial model IPEC-J2: Effects on tight junctions and apoptosis
The plant alkaloid berberine has been shown to have many beneficial effects on human health. This has led to its use as a treatment for various cancer types, obesity, and diabetes. Moreover, a described barrier-strengthening effect in human cancer cell lines indicates that it might be useful for the treatment of inflammatory bowel disease. Detailed information regarding its effects on intestinal epithelium remains limited. In our current study, we describe the impact of berberine on a non-transformed porcine small intestinal epithelial cell model, IPEC-J2. Incubation of IPEC-J2 monolayers with berberine revealed dose- and time-dependent effects on barrier properties. A viability assay confirmed the specific effect of berberine on the apoptotic pathway, paralleled by the internalization of the sealing tight-junction (TJ) proteins claudin-1, claudin-3, and occludin within 6 h. Hence, the barrier function of the cells was reduced, as shown by the reduced transepithelial electrical resistance and the increased [3H]-D-Mannitol flux. A decrease of claudin-1, claudin-3, and occludin expression was also observed after 24 h, whereas ZO-1 expression was not significantly changed. These data indicate an early effect on both cell viability and barrier integrity, followed by a general effect on TJ architecture. The intracellular co-localization of claudin-1 and occludin or claudin-3 and occludin points to an initial induction of apoptosis accompanied by the internalization of sealing TJ proteins. Although barrier strengthening has been reported in cancerogenic epithelial models, our results show a barrier-weakening action, which represents a new aspect of the effect of berberine on epithelia. These results agree with the known toxic potential of plant alkaloids in general and show that berberine is also capable of exerting adverse effects in the intestinal epithelium
A quasi experimental study in the EuCARE project
Funding Information: This research received contributions from the EuCARE Project funded by the European Union's Horizon Europe Research and Innovation Program under Grant Agreement No 101046016. Funding Information: This research received contributions from the EuCARE Project funded by the European Union's Horizon Europe Research and Innovation Program under Grant Agreement No 101046016. Federica Bellerba is a PhD student at the European School of Molecular Medicine (SEMM), Milan, Italy. We would like to sincerely thank Maria Pia Fabiani for checking and proofreading the English language of the manuscript, contributing to its overall quality and readability. We thank Iuri Fanti for his contribution to the data management of the EuCARE school studies. We also wish to extend our gratitude to Maurizio Rainisio for his invaluable methodological input and insightful points of reflection that have significantly enhanced the quality of this study. FB, FI and SG contributed to the conceptualisation of the study. FB and SG contributed to the data analysis, interpretation of the results, writing, and reviewing of the manuscript. ODE, SR, ET, and FI contributed to the interpretation of the results, writing, and reviewing of the manuscript. NB, MB, MSM, IMA, DA, AA, and RK contributed to data collection, supervision, and reviewing of the manuscript. ES and NP contributed to the interpretation of the results and reviewing of the methodology and the manuscript. FI contributed to the funding acquisition. VG, EG, GV, and CM contributed to the data management, supervision, and reviewing of the manuscript. FI and CM contributed to the project administration. Publisher Copyright: © 2023 The AuthorsObjectives: We investigated the impact of school reopening on SARS-CoV-2 transmission in Italy, Germany, and Portugal in autumn 2022 when the Omicron variant was prevalent. Methods: A prospective international study was conducted using the case reproduction number (Rc) calculated with the time parametrization of Omicron. For Germany and Italy, staggered difference-in-differences analysis was employed to explore the causal relationship between school reopening and Rc changes, accounting for varying reopening dates. In Portugal, interrupted time series analysis was used due to simultaneous school reopenings. Multivariable models were adopted to adjust for confounders. Results: In Italy and Germany, post-reopening Rc estimates were significantly lower compared to those from regions/states that had not yet reopened at the same time points, both in the student population (overall average treatment effect for the treated subpopulation [O-ATT]: -0.80 [95% CI: -0.94;-0.66] for Italy; O-ATT-0.30 [95% CI: -0.36;-0.23] for Germany) and the adult population (O-ATT: -0.04 [95% CI: -0.07;-0.01] for Italy; O-ATT: -0.07 [95% CI: -0.11;-0.03] for Germany). In Portugal, there was a significant decreasing trend in Rc following school reopenings compared to the pre-reopening period (sustained effect: -0.03 [95% CI: -0.04; -0.03] in students; -0.02 [95% CI: -0.03; -0.02] in adults). Conclusions: We found no evidence of a causal relationship between school reopenings in autumn 2022 and Omicron SARS-CoV-2 transmission.publishersversionpublishe
Macroevolution of the plant–hummingbird pollination system
ABSTRACTPlant–hummingbird interactions are considered a classic example of coevolution, a process in which mutually dependent species influence each other's evolution. Plants depend on hummingbirds for pollination, whereas hummingbirds rely on nectar for food. As a step towards understanding coevolution, this review focuses on the macroevolutionary consequences of plant–hummingbird interactions, a relatively underexplored area in the current literature. We synthesize prior studies, illustrating the origins and dynamics of hummingbird pollination across different angiosperm clades previously pollinated by insects (mostly bees), bats, and passerine birds. In some cases, the crown age of hummingbirds pre‐dates the plants they pollinate. In other cases, plant groups transitioned to hummingbird pollination early in the establishment of this bird group in the Americas, with the build‐up of both diversities coinciding temporally, and hence suggesting co‐diversification. Determining what triggers shifts to and away from hummingbird pollination remains a major open challenge. The impact of hummingbirds on plant diversification is complex, with many tropical plant lineages experiencing increased diversification after acquiring flowers that attract hummingbirds, and others experiencing no change or even a decrease in diversification rates. This mixed evidence suggests that other extrinsic or intrinsic factors, such as local climate and isolation, are important covariables driving the diversification of plants adapted to hummingbird pollination. To guide future studies, we discuss the mechanisms and contexts under which hummingbirds, as a clade and as individual species (e.g. traits, foraging behaviour, degree of specialization), could influence plant evolution. We conclude by commenting on how macroevolutionary signals of the mutualism could relate to coevolution, highlighting the unbalanced focus on the plant side of the interaction, and advocating for the use of species‐level interaction data in macroevolutionary studies
Genome-wide association study identifies eight risk loci and implicates metabo-psychiatric origins for anorexia nervosa
Characterized primarily by a low body-mass index, anorexia nervosa is a complex and serious illness1, affecting 0.9-4% of women and 0.3% of men2-4, with twin-based heritability estimates of 50-60%5. Mortality rates are higher than those in other psychiatric disorders6, and outcomes are unacceptably poor7. Here we combine data from the Anorexia Nervosa Genetics Initiative (ANGI)8,9 and the Eating Disorders Working Group of the Psychiatric Genomics Consortium (PGC-ED) and conduct a genome-wide association study of 16,992 cases of anorexia nervosa and 55,525 controls, identifying eight significant loci. The genetic architecture of anorexia nervosa mirrors its clinical presentation, showing significant genetic correlations with psychiatric disorders, physical activity, and metabolic (including glycemic), lipid and anthropometric traits, independent of the effects of common variants associated with body-mass index. These results further encourage a reconceptualization of anorexia nervosa as a metabo-psychiatric disorder. Elucidating the metabolic component is a critical direction for future research, and paying attention to both psychiatric and metabolic components may be key to improving outcomes
Human cerebrospinal fluid monoclonal CASPR2 autoantibodies induce changes in electrophysiology, functional MRI, and behavior in rodent models
Anti-contactin associated protein receptor 2 (CASPR2) encephalitis is a severe autoimmune encephalitis with a variable clinical phenotype including behavioral abnormalities, cognitive decline, epileptic seizures, peripheral nerve hyperexcitability and neuropathic pain. The detailed mechanisms of how CASPR2 autoantibodies lead to synaptic dysfunction and clinical symptoms are largely unknown. Aiming for analyses from the molecular to the clinical level, we isolated antibody-secreting cells from the cerebrospinal fluid of two patients with CASPR2 encephalitis. From these we cloned four anti-CASPR2 human monoclonal autoantibodies (mAbs) with strong binding to brain and peripheral nerves. All were highly hypermutated and mainly of the IgG4 subclass. Mutagenesis studies determined selective binding to the discoidin domain of CASPR2. Surface plasmon resonance revealed affinities with dissociation constants K D in the pico- to nanomolar range. CASPR2 mAbs interrupted the interaction of CASPR2 with its binding partner contactin 2 in vitro and were internalized after binding to CASPR2-expressing cells. Electrophysiological recordings of rat hippocampal slices after stereotactic injection of CASPR2 mAbs showed characteristic afterpotentials following electrical stimulation. In vivo experiments with intracerebroventricular administration of human CASPR2 mAbs into mice and rats showed EEG-recorded brain hyperexcitability but no spontaneous recurrent seizures. Behavioral assessment of infused mice showed a subtle clinical phenotype, mainly affecting sociability. Mouse brain MRI exhibited markedly reduced resting-state functional connectivity without short-term structural changes. Together, the experimental data support the direct pathogenicity of CASPR2 autoantibodies. The minimally invasive EEG and MRI techniques applied here may serve as novel objective, quantifiable tools for improved animal models, in particular for subtle neuropsychiatric phenotypes or repeated measurements
Encephalitis patient-derived monoclonal GABAA receptor antibodies cause epileptic seizures
Autoantibodies targeting the GABAA receptor (GABAAR) hallmark an autoimmune encephalitis presenting with frequent seizures and psychomotor abnormalities. Their pathogenic role is still not well-defined, given the common overlap with further autoantibodies and the lack of patient-derived mAbs. Five GABAAR mAbs from cerebrospinal fluid cells bound to various epitopes involving the α1 and γ2 receptor subunits, with variable binding strength and partial competition. mAbs selectively reduced GABAergic currents in neuronal cultures without causing receptor internalization. Cerebroventricular infusion of GABAAR mAbs and Fab fragments into rodents induced a severe phenotype with seizures and increased mortality, reminiscent of encephalitis patients' symptoms. Our results demonstrate direct pathogenicity of autoantibodies on GABAARs independent of Fc-mediated effector functions and provide an animal model for GABAAR encephalitis. They further provide the scientific rationale for clinical treatments using antibody depletion and can serve as tools for the development of antibody-selective immunotherapies
Common Genetic Variation And Age at Onset Of Anorexia Nervosa
Background Genetics and biology may influence the age at onset of anorexia nervosa (AN). The aims of this study were to determine whether common genetic variation contributes to AN age at onset and to investigate the genetic associations between age at onset of AN and age at menarche. Methods A secondary analysis of the Psychiatric Genomics Consortium genome-wide association study (GWAS) of AN was performed which included 9,335 cases and 31,981 screened controls, all from European ancestries. We conducted GWASs of age at onset, early-onset AN (< 13 years), and typical-onset AN, and genetic correlation, genetic risk score, and Mendelian randomization analyses. Results Two loci were genome-wide significant in the typical-onset AN GWAS. Heritability estimates (SNP-h2) were 0.01-0.04 for age at onset, 0.16-0.25 for early-onset AN, and 0.17-0.25 for typical-onset AN. Early- and typical-onset AN showed distinct genetic correlation patterns with putative risk factors for AN. Specifically, early-onset AN was significantly genetically correlated with younger age at menarche, and typical-onset AN was significantly negatively genetically correlated with anthropometric traits. Genetic risk scores for age at onset and early-onset AN estimated from independent GWASs significantly predicted age at onset. Mendelian randomization analysis suggested a causal link between younger age at menarche and early-onset AN. Conclusions Our results provide evidence consistent with a common variant genetic basis for age at onset and implicate biological pathways regulating menarche and reproduction.Peer reviewe
Shared genetic risk between eating disorder- and substance-use-related phenotypes:Evidence from genome-wide association studies
First published: 16 February 202
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