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1.
Proc Natl Acad Sci U S A ; 121(9): e2315985121, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38377192

RESUMO

Recurrent, ancient arms races between viruses and hosts have shaped both host immunological defense strategies as well as viral countermeasures. One such battle is waged by the glycoprotein US11 encoded by the persisting human cytomegalovirus. US11 mediates degradation of major histocompatibility class I (MHC-I) molecules to prevent CD8+ T-cell activation. Here, we studied the consequences of the arms race between US11 and primate MHC-A proteins, leading us to uncover a tit-for-tat coevolution and its impact on MHC-A diversification. We found that US11 spurred MHC-A adaptation to evade viral antagonism: In an ancestor of great apes, the MHC-A A2 lineage acquired a Pro184Ala mutation, which confers resistance against the ancestral US11 targeting strategy. In response, US11 deployed a unique low-complexity region (LCR), which exploits the MHC-I peptide loading complex to target the MHC-A2 peptide-binding groove. In addition, the global spread of the human HLA-A*02 allelic family prompted US11 to employ a superior LCR strategy with an optimally fitting peptide mimetic that specifically antagonizes HLA-A*02. Thus, despite cytomegaloviruses low pathogenic potential, the increasing commitment of US11 to MHC-A has significantly promoted diversification of MHC-A in hominids.


Assuntos
Antígenos de Histocompatibilidade Classe I , Hominidae , Animais , Humanos , Proteínas Virais/metabolismo , Citomegalovirus , Hominidae/genética , Hominidae/metabolismo , Linhagem Celular , Antígenos de Histocompatibilidade/metabolismo , Antígenos HLA-A/metabolismo , Peptídeos/metabolismo
2.
Cereb Cortex ; 34(1)2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-37991275

RESUMO

Neuroimage studies have reported functional connectome abnormalities in posttraumatic stress disorder (PTSD), especially in adults. However, these studies often treated the brain as a static network, and time-variance of connectome topology in pediatric posttraumatic stress disorder remain unclear. To explore case-control differences in dynamic connectome topology, resting-state functional magnetic resonance imaging data were acquired from 24 treatment-naïve non-comorbid pediatric posttraumatic stress disorder patients and 24 demographically matched trauma-exposed non-posttraumatic stress disorder controls. A graph-theoretic analysis was applied to construct time-varying modular structure of whole-brain networks by maximizing the multilayer modularity. Network switching rate at the global, subnetwork, and nodal levels were calculated and compared between posttraumatic stress disorder and trauma-exposed non-posttraumatic stress disorder groups, and their associations with posttraumatic stress disorder symptom severity and sex interactions were explored. At the global level, individuals with posttraumatic stress disorder exhibited significantly lower network switching rates compared to trauma-exposed non-posttraumatic stress disorder controls. This difference was mainly involved in default-mode and dorsal attention subnetworks, as well as in inferior temporal and parietal brain nodes. Posttraumatic stress disorder symptom severity was negatively correlated with switching rate in the global network and default mode network. No significant differences were observed in the interaction between diagnosis and sex/age. Pediatric posttraumatic stress disorder is associated with dynamic reconfiguration of brain networks, which may provide insights into the biological basis of this disorder.


Assuntos
Conectoma , Transtornos de Estresse Pós-Traumáticos , Adulto , Humanos , Criança , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Rede Nervosa , Encéfalo , Conectoma/métodos
3.
Cereb Cortex ; 33(23): 11373-11383, 2023 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-37804248

RESUMO

Post-traumatic stress symptoms and post-traumatic growth are common co-occurring psychological responses following exposure to traumatic events (such as COVID-19 pandemic), their mutual relationship remains unclear. To explore this relationship, structural magnetic resonance imaging data were acquired from 115 general college students before the COVID-19 pandemic, and follow-up post-traumatic stress symptoms and post-traumatic growth measurements were collected during the pandemic. Voxel-based morphometry was conducted and individual structural covariance networks based on gray matter volume were further analyzed using graph theory and partial least squares correlation. Behavioral correlation found no significant relationship between post-traumatic stress symptoms and post-traumatic growth. Voxel-based morphometry analyses showed that post-traumatic stress symptoms were positively correlated with gray matter volume in medial prefrontal cortex/dorsal anterior cingulate cortex, and post-traumatic growth was negatively correlated with gray matter volume in left dorsolateral prefrontal cortex. Structural covariance network analyses found that post-traumatic stress symptoms were negatively correlated with the local efficiency and clustering coefficient of the network. Moreover, partial least squares correlation showed that post-traumatic stress symptoms were correlated with pronounced nodal properties patterns in default mode, sensory and motor regions, and a marginal correlation of post-traumatic growth with a nodal property pattern in emotion regulation-related regions. This study advances our understanding of the neurobiological substrates of post-traumatic stress symptoms and post-traumatic growth, and suggests that they may have different neuroanatomical features.


Assuntos
COVID-19 , Crescimento Psicológico Pós-Traumático , Transtornos de Estresse Pós-Traumáticos , Humanos , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Pandemias , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Imageamento por Ressonância Magnética/métodos
4.
Drug Metab Rev ; 55(4): 371-387, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37593784

RESUMO

Cholestatic liver injury (CLI) is caused by toxic bile acids (BAs) accumulation in the liver and can lead to inflammation and liver fibrosis. The mechanisms underlying CLI development remain unclear, and this disease has no effective cure. However, regulating BA synthesis and homeostasis represents a promising therapeutic strategy for CLI treatment. Pregnane X receptor (PXR) plays an essential role in the metabolism of endobiotics and xenobiotics via the transcription of metabolic enzymes and transporters, which can ultimately modulate BA homeostasis and exert anticholestatic effects. Furthermore, recent studies have demonstrated that PXR exhibits antifibrotic and anti-inflammatory properties, providing novel insights into treating CLI. Meanwhile, several drugs have been identified as PXR agonists that improve CLI. Nevertheless, the precise role of PXR in CLI still needs to be fully understood. This review summarizes how PXR improves CLI by ameliorating cholestasis, inhibiting inflammation, and reducing fibrosis and discusses the progress of promising PXR agonists for treating CLI.


Assuntos
Colestase , Receptores de Esteroides , Humanos , Receptor de Pregnano X/metabolismo , Receptores de Esteroides/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Fígado/metabolismo , Colestase/tratamento farmacológico , Colestase/metabolismo , Ácidos e Sais Biliares/metabolismo , Ácidos e Sais Biliares/farmacologia , Ácidos e Sais Biliares/uso terapêutico , Inflamação
5.
Cell Biol Int ; 47(12): 1926-1941, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37655479

RESUMO

α7-Nicotinic acetylcholine receptor (α7-nAChR) is the key effector molecule of the cholinergic anti-inflammatory pathway. Evolution has evolved a uniquely human α7-nAChR encoded by CHRFAM7A. It has been demonstrated that CHRFAM7A dominant negatively regulates the functions of α7-nAChR. However, its role in inflammation remains to be fully characterized. CHRFAM7A transgenic (Tg) mice were phenotypically normal and their peritoneal macrophages exhibited decreased ligand-binding capability and, importantly, an activated gene expression profile of pro-inflammatory cytokines. Surprisingly, when challenged with sepsis, the Tg mice showed no survival disadvantage relative to their wild-type (Wt) counterparts. Further analysis showed that the complete blood count and serum levels of pro-inflammatory cytokines were comparable at resting state, but the degrees of leukocyte mobilization and the increase of pro-inflammatory cytokines were significantly higher in Tg than Wt mice at the early stage of sepsis. In vitro, peritoneal macrophages of the Tg mice exhibited an exaggerated response to lipopolysaccharides (LPSs), especially at the earlier time points and at lower dosages of LPS. Remarkably, monocytes from CHRFAM7A-carrier showed similar dynamic changes of the pro-inflammatory cytokines to that observed in the Tg mice upon LPS challenge. Our results suggest that CHRFAM7A increases the mobilization of leukocytes and primes macrophages that confer an enhanced immune response at the early stage of inflammation, which may lead to prompt pathogen clearance, an evolutionary advantage in less severe inflammatory conditions.


Assuntos
Lipopolissacarídeos , Sepse , Animais , Humanos , Camundongos , Citocinas , Inflamação , Lipopolissacarídeos/farmacologia , Macrófagos , Camundongos Transgênicos
6.
Cell Mol Biol (Noisy-le-grand) ; 69(14): 88-93, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38279470

RESUMO

Breast cancer (BC) is a common gynaecological malignancy worldwide. Long noncoding RNAs (lncRNAs) were identified to take part in the regulation of the occurrence and development of tumors. LncRNA The role of LINC00467 in lung adenocarcinoma has been reported, but its mechanism remains unclear in BC. To explore the role of LINC00467 deeply, we designed and performed a series of experiments. According to the result, it was discovered that LINC00467 was overexpressed in BC tissues and cells, and then the knockdown of LINC00467 resulted in a decline in cell growth and metastasis. Mechanistically, miR-18a/b-5p was screened out and validated to bind with LINC00467. Additionally, LINC00467 was negatively correlated with miR-18a/b-5p. Hereafter, there is evidence that miR-18a/b-5p targets MAPK4. Rescue assays suggested that MAPK4 amplification recovered the inhibitive effect of LINC00467 knockdown on cell growth and metastasis. In a word, LINC00467 enhanced BC cell growth and metastasis by targeting miR-18a/b-5p/MAPK4, which implies a potential revelation for exploring the therapeutic tactic of BC.


Assuntos
Neoplasias da Mama , MicroRNAs , RNA Longo não Codificante , Feminino , Humanos , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/genética
7.
J Nanobiotechnology ; 21(1): 247, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37528366

RESUMO

Lymph node metastasis is a frequent occurrence in a variety of tumour forms and poses an enormous challenge to cancer treatment. This process is critical to the development of the disease and is frequently linked to a poor prognosis. Over 90% of cancerous cells move through lymph nodes, making them important entry routes for the spread of cancer cells. The prognosis of cancer patients is significantly impacted by lymph node metastases, which also affects treatment choices. Targeting lymph node metastases presents numerous difficulties for conventional medication delivery techniques. It is still very difficult to selectively target cancer cells in lymph nodes without risking injury to healthy organs and unforeseen consequences. Additionally, systemic delivery of drugs is hampered by the slow flow rate of lymphatic vessels. Chemotherapeutic medicines' poor solubility and stability further reduce their effectiveness when taken orally. Additionally, the extracellular matrix that surrounds lymph node tumours is extensive, which makes it difficult for conventional pharmaceutical delivery systems to reach cancer cells. The development of nanocarriers for precise drug delivery to LNs has attracted a lot of interest to overcome these obstacles. Most solid tumours first spread through the lymphatic system, hence effective drug administration to these tissues is essential for better therapeutic results. Nanocarriers have several benefits, including the capacity to pass through barriers like blood-brain barriers and membranes to reach the lymphatic system. High medication dosages can be enclosed thanks to the physicochemical characteristics of nanocarriers, such as their higher surface-to-volume ratio. Additionally, ligands, antibodies, polymers, or biological molecules can be attached to nanocarrier surfaces to change their properties, allowing for the targeted delivery of lymph node epithelial cells. This use of nanocarriers for drug delivery maximizes on-target effects and related adverse effects while improving the effectiveness of medication delivery to target locations. More research and development in this field is needed to optimize nanocarrier design, increase targeting capabilities, and expand clinical applications for better cancer care.


Assuntos
Sistemas de Liberação de Medicamentos , Nanopartículas , Humanos , Metástase Linfática/patologia , Sistema Linfático , Linfonodos/patologia , Barreira Hematoencefálica , Nanopartículas/química
8.
Neuroimage ; 255: 119185, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35398284

RESUMO

As characterized by repeated exposure of others' trauma, vicarious traumatization is a common negative psychological reaction during the COVID-19 pandemic and plays a crucial role in the development of general mental distress. This study aims to identify functional connectome that encodes individual variations of pandemic-related vicarious traumatization and reveal the underlying brain-vicarious traumatization mechanism in predicting general distress. The eligible subjects were 105 general university students (60 females, aged from 19 to 27 years) undergoing brain MRI scanning and baseline behavioral tests (October 2019 to January 2020), whom were re-contacted for COVID-related vicarious traumatization measurement (February to April 2020) and follow-up general distress evaluation (March to April 2021). We applied a connectome-based predictive modeling (CPM) approach to identify the functional connectome supporting vicarious traumatization based on a 268-region-parcellation assigned to network memberships. The CPM analyses showed that only the negative network model stably predicted individuals' vicarious traumatization scores (q2 = -0.18, MSE = 617, r [predicted, actual] = 0.18, p = 0.024), with the contributing functional connectivity primarily distributed in the fronto-parietal, default mode, medial frontal, salience, and motor network. Furthermore, mediation analysis revealed that vicarious traumatization mediated the influence of brain functional connectome on general distress. Importantly, our results were independent of baseline family socioeconomic status, other stressful life events and general mental health as well as age, sex and head motion. Our study is the first to provide evidence for the functional neural markers of vicarious traumatization and reveal an underlying neuropsychological pathway to predict distress symptoms in which brain functional connectome affects general distress via vicarious traumatization.


Assuntos
COVID-19 , Fadiga de Compaixão , Conectoma , Encéfalo/diagnóstico por imagem , Fadiga de Compaixão/epidemiologia , Fadiga de Compaixão/psicologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Saúde Mental , Pandemias
9.
Neuropsychol Rev ; 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36125651

RESUMO

Recent graph-theoretical studies of Parkinson's disease (PD) have examined alterations in the global properties of the brain structural connectome; however, reported alterations are not consistent. The present study aimed to identify the most robust global metric alterations in PD via a meta-analysis. A comprehensive literature search was conducted for all available diffusion MRI structural connectome studies that compared global graph metrics between PD patients and healthy controls (HC). Hedges' g effect sizes were calculated for each study and then pooled using a random-effects model in Comprehensive Meta-Analysis software, and the effects of potential moderator variables were tested. A total of 22 studies met the inclusion criteria for review. Of these, 16 studies reporting 10 global graph metrics (916 PD patients; 560 HC) were included in the meta-analysis. In the structural connectome of PD patients compared with HC, we found a significant decrease in clustering coefficient (g = -0.357, P = 0.005) and global efficiency (g = -0.359, P < 0.001), and a significant increase in characteristic path length (g = 0.250, P = 0.006). Dopaminergic medication, sex and age of patients were potential moderators of global brain network changes in PD. These findings provide evidence of decreased global segregation and integration of the structural connectome in PD, indicating a shift from a balanced small-world network to 'weaker small-worldization', which may provide useful markers of the pathophysiological mechanisms underlying PD.

10.
Europace ; 24(12): 2028-2036, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-35894107

RESUMO

AIMS: A loss-of-function mutation in L-type calcium (Ca2+) channel subunit gene CACNB2 has been reported to cause short QT syndrome subtype 5 (SQT5). However, the mechanism underlying the loss-of-function of the Ca2+ channel has not been clarified. In the present study, we aim to explore the DNA methylation mechanism of L-type Ca2+ channel downregulation in human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) of SQT5. METHODS AND RESULTS: The hiPSC-CMs were generated from a healthy donor and a SQT5 patient carrying the CACNB2 variant c.1439C > T/p.S480L. The variant was genetically corrected using ribonucleoprotein-based CRISPR/Cas9 technique to obtain an isogenic control cell line. The action potential (AP) and Ca2+ current were measured by patch clamp. Protein expression levels were determined by western blotting. Dot blotting and bisulfite sequence were performed for epigenetic study. Our results showed that AP durations at 10% repolarization (APD10) and 50% repolarization (APD50) were significantly shortened in SQT5 cells and both the expression level of the ß-subunit and channel current of L-type Ca2+ channel were reduced. Besides, an increased level of whole-genome DNA methylation and DNA methylation of CpG island in the promoter region of CACNB2 gene was detected. Overexpression of demethylation enzyme could rescue the decreased expression of CACNB2 and the L-type Ca2+ current. CONCLUSION: In SQT5 hiPSC-CMs carrying the CACNB2-S480L variant, the decreased L-type Ca2+ current resulting from decreased CACNB2 protein expression was caused by enhanced methylation in the promoter region of the CACNB2 gene and upregulation of DNA methyltransferases might be one of the mechanisms.


Assuntos
Células-Tronco Pluripotentes Induzidas , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Canais de Cálcio Tipo L/genética , Canais de Cálcio Tipo L/metabolismo , Miócitos Cardíacos/metabolismo , Arritmias Cardíacas , Potenciais de Ação , Mutação
11.
Exp Cell Res ; 408(2): 112858, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34600901

RESUMO

In contrast to conventional cancer treatment, in personalized cancer medicine each patient receives a specific treatment. The response to therapy, clinical outcomes, and tumor behavior such as metastases, tumor progression, carcinogenesis can be significantly affected by the heterogeneous tumor microenvironment (TME) and interpersonal differences. Therefore, using native tumor microenvironment mimicking models is necessary to improving personalized cancer therapy. Both in vitro 2D cell culture and in vivo animal models poorly recapitulate the heterogeneous tumor (immune) microenvironments of native tumors. The development of 3D culture models, native tumor microenvironment mimicking models, made it possible to evaluate the chemoresistance of tumor tissue and the functionality of drugs in the presence of cell-extracellular matrix and cell-cell interactions in a 3D construction. Various personalized tumor models have been designed to preserving the native tumor microenvironment, including patient-derived tumor xenografts and organoid culture strategies. In this review, we will discuss the patient-derived organoids as a native tumor microenvironment mimicking model in personalized cancer therapy. In addition, we will also review the potential and the limitations of organoid culture systems for predicting patient outcomes and preclinical drug screening. Finally, we will discuss immunotherapy drug screening in tumor organoids by using microfluidic technology.


Assuntos
Matriz Extracelular/genética , Neoplasias/terapia , Organoides/imunologia , Microambiente Tumoral/genética , Técnicas de Cultura de Células , Matriz Extracelular/imunologia , Humanos , Imunoterapia , Neoplasias/imunologia , Neoplasias/patologia , Medicina de Precisão , Microambiente Tumoral/imunologia
12.
Int J Mol Sci ; 23(15)2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35955449

RESUMO

Aims: Some gene variants in the sodium channels, as well as calcium channels, have been associated with Brugada syndrome (BrS). However, the investigation of the human cellular phenotype and the use of drugs for BrS in presence of variant in the calcium channel subunit is still lacking. Objectives: The objective of this study was to establish a cellular model of BrS in the presence of a CACNB2 variant of uncertain significance (c.425C > T/p.S142F) using human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) and test drug effects using this model. Methods and results: This study recruited cells from a patient with Brugada syndrome (BrS) and recurrent ventricular fibrillation carrying a missense variant in CACNB2 as well as from three healthy independent persons. These cells (hiPSC-CMs) generated from skin biopsies of healthy persons and the BrS patient (BrS-hiPSC-CMs) as well as CRISPR/Cas9 corrected cells (isogenic control, site-variant corrected) were used for this study. The hiPSC-CMs from the BrS patient showed a significantly reduced L-type calcium channel current (ICa-L) compared with the healthy control hiPSC-CMs. The inactivation curve was shifted to a more positive potential and the recovery from inactivation was accelerated. The protein expression of CACNB2 of the hiPSC-CMs from the BrS-patient was significantly decreased compared with healthy hiPSC-CMs. Moreover, the correction of the CACNB2 site-variant rescued the changes seen in the hiPSC-CMs of the BrS patient to the normal state. These data indicate that the CACNB2 gene variant led to loss-of-function of L-type calcium channels in hiPSC-CMs from the BrS patient. Strikingly, arrhythmia events were more frequently detected in BrS-hiPSC-CMs. Bisoprolol (beta-blockers) at low concentration and quinidine decreased arrhythmic events. Conclusions: The CACNB2 variant (c.425C > T/p.S142F) causes a loss-of-function of L-type calcium channels and is pathogenic for this type of BrS. Bisoprolol and quinidine may be effective for treating BrS with this variant.


Assuntos
Síndrome de Brugada , Células-Tronco Pluripotentes Induzidas , Potenciais de Ação , Arritmias Cardíacas/metabolismo , Bisoprolol/farmacologia , Canais de Cálcio Tipo L/genética , Canais de Cálcio Tipo L/metabolismo , Humanos , Miócitos Cardíacos/metabolismo , Quinidina/farmacologia
13.
Circulation ; 142(11): 1059-1076, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32623905

RESUMO

BACKGROUND: Noonan syndrome (NS) is a multisystemic developmental disorder characterized by common, clinically variable symptoms, such as typical facial dysmorphisms, short stature, developmental delay, intellectual disability as well as cardiac hypertrophy. The underlying mechanism is a gain-of-function of the RAS-mitogen-activated protein kinase signaling pathway. However, our understanding of the pathophysiological alterations and mechanisms, especially of the associated cardiomyopathy, remains limited and effective therapeutic options are lacking. METHODS: Here, we present a family with two siblings displaying an autosomal recessive form of NS with massive hypertrophic cardiomyopathy as clinically the most prevalent symptom caused by biallelic mutations within the leucine zipper-like transcription regulator 1 (LZTR1). We generated induced pluripotent stem cell-derived cardiomyocytes of the affected siblings and investigated the patient-specific cardiomyocytes on the molecular and functional level. RESULTS: Patients' induced pluripotent stem cell-derived cardiomyocytes recapitulated the hypertrophic phenotype and uncovered a so-far-not-described causal link between LZTR1 dysfunction, RAS-mitogen-activated protein kinase signaling hyperactivity, hypertrophic gene response and cellular hypertrophy. Calcium channel blockade and MEK inhibition could prevent some of the disease characteristics, providing a molecular underpinning for the clinical use of these drugs in patients with NS, but might not be a sustainable therapeutic option. In a proof-of-concept approach, we explored a clinically translatable intronic CRISPR (clustered regularly interspaced short palindromic repeats) repair and demonstrated a rescue of the hypertrophic phenotype. CONCLUSIONS: Our study revealed the human cardiac pathogenesis in patient-specific induced pluripotent stem cell-derived cardiomyocytes from NS patients carrying biallelic variants in LZTR1 and identified a unique disease-specific proteome signature. In addition, we identified the intronic CRISPR repair as a personalized and in our view clinically translatable therapeutic strategy to treat NS-associated hypertrophic cardiomyopathy.


Assuntos
Sistemas CRISPR-Cas , Cardiomiopatias , Terapia Genética , Células-Tronco Pluripotentes Induzidas/metabolismo , Modelos Cardiovasculares , Mutação , Miócitos Cardíacos/metabolismo , Síndrome de Noonan , Fatores de Transcrição , Cardiomiopatias/genética , Cardiomiopatias/metabolismo , Cardiomiopatias/terapia , Humanos , Íntrons , Síndrome de Noonan/genética , Síndrome de Noonan/metabolismo , Síndrome de Noonan/terapia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
14.
Cancer Sci ; 112(7): 2592-2606, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33938090

RESUMO

Immunotherapy has revolutionized cancer treatment, however, not all tumor types and patients are completely responsive to this approach. Establishing predictive pre-clinical models would allow for more accurate and practical immunotherapeutic drug development. Mouse models are extensively used as in vivo system for biomedical research. However, due to the significant differences between rodents and human, it is impossible to translate most of the findings from mouse models to human. Pharmacological development and advancing personalized medicine using patient-derived xenografts relies on producing mouse models in which murine cells and genes are substituted with their human equivalent. Humanized mice (HM) provide a suitable platform to evaluate xenograft growth in the context of a human immune system. In this review, we discussed recent advances in the generation and application of HM models. We also reviewed new insights into the basic mechanisms, pre-clinical evaluation of onco-immunotherapies, current limitations in the application of these models as well as available improvement strategies. Finally, we pointed out some issues for future studies.


Assuntos
Modelos Animais de Doenças , Imunoterapia , Neoplasias/terapia , Ensaios Antitumorais Modelo de Xenoenxerto , Animais , Anticorpos Monoclonais/uso terapêutico , Citocinas/metabolismo , Desenvolvimento de Medicamentos , Engenharia Genética , Rejeição de Enxerto/imunologia , Doença Enxerto-Hospedeiro/prevenção & controle , Humanos , Imunoterapia Adotiva/métodos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Células Matadoras Naturais/imunologia , Camundongos , Camundongos SCID , Neoplasias/imunologia , Medicina de Precisão , Pesquisa Translacional Biomédica , Transplante Heterólogo
15.
Hum Brain Mapp ; 42(10): 3156-3167, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33769638

RESUMO

Neuroimaging studies using a variety of techniques have demonstrated abnormal patterns of spontaneous brain activity in patients with essential tremor (ET). However, the findings are variable and inconsistent, hindering understanding of underlying neuropathology. We conducted a meta-analysis of whole-brain resting-state functional neuroimaging studies in ET compared to healthy controls (HC), using anisotropic effect-size seed-based d mapping, to identify the most consistent brain activity alterations and their relation to clinical features. After systematic literature search, we included 13 studies reporting 14 comparisons, describing 286 ET patients and 254 HC. Subgroup analyses were conducted considering medication status, head tremor status, and methodological factors. Brain activity in ET is altered not only in the cerebellum and cerebral motor cortex, but also in nonmotor cortical regions including prefrontal cortex and insula. Most of the results remained unchanged in subgroup analyses of patients with head tremor, medication-naive patients, studies with statistical threshold correction, and the large subgroup of studies using functional magnetic resonance imaging. These findings not only show consistent and robust abnormalities in specific brain regions but also provide new information on the biology of patient heterogeneity, and thus help to elucidate the pathophysiology of ET.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Conectoma , Tremor Essencial/diagnóstico por imagem , Tremor Essencial/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Descanso
16.
Europace ; 23(7): 1137-1148, 2021 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-33604602

RESUMO

AIMS: This study aimed to investigate possible roles and underlying mechanisms of alpha-adrenoceptor coupled signalling for the pathogenesis of Takotsubo syndrome (TTS). METHODS AND RESULTS: Human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) were treated with a toxic concentration of epinephrine (Epi, 0.5 mM for 1 h) to mimic the setting of TTS. Patch-clamp technique, polymerase chain reaction (PCR) and Fluorescence-activated cell sorting (FACS) were employed for the study. High concentration Epi suppressed the depolarization velocity, prolonged duration of action potentials and induced arrhythmic events in hiPSC-CMs. The Epi effects were attenuated by an alpha-adrenoceptor blocker (phentolamine), suggesting involvement of alpha-adrenoceptor signalling in arrhythmogenesis related to QT interval prolongation in the setting of TTS. An alpha 1-adrenoceptor agonist (phenylephrine) but not an alpha 2-adrenoceptor agonist (clonidine) mimicked Epi effects. Epi enhanced ROS production, which could be attenuated by the alpha- adrenoceptor blocker. Treatment of cells with H2O2 (100 µM) mimicked the effects of Epi on action potentials and a reactive oxygen species (ROS)-blocker (N-acetyl-I-cysteine, 1 mM) prevented the Epi effects, indicating that the ROS signalling is involved in the alpha-adrenoceptor actions. Nicotinamide adenine dinucleotide phosphate hydrogen (NADPH) oxidases were involved in alpha 1-adrenoceptor signalling. A protein kinase C (PKC) blocker suppressed the effects of Epi, phenylephrine and ROS as well, implying that PKC participated in alpha 1-adrenoceptor signalling and acted as a downstream factor of ROS. The abnormal action potentials resulted from alpha 1-adrenoceptor activation-induced dysfunctions of ion channels including the voltage-dependent Na+ and L-type Ca2+ channels. CONCLUSIONS: Alpha 1-adrenoceptor signalling plays important roles for arrhythmogenesis of TTS. Alpha-adrenoceptor blockers might be clinically helpful for treating arrhythmias in patients with TTS.


Assuntos
Células-Tronco Pluripotentes Induzidas , Miócitos Cardíacos , Potenciais de Ação , Catecolaminas/toxicidade , Humanos , Peróxido de Hidrogênio , Receptores Adrenérgicos alfa 1
17.
Mediators Inflamm ; 2021: 5514075, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34539242

RESUMO

The integrity and permeability of the intestinal epithelial barrier are important indicators of intestinal health. Impaired intestinal epithelial barrier function and increased intestinal permeability are closely linked to the onset and progression of various intestinal diseases. Sinapic acid (SA) is a phenolic acid that has anti-inflammatory, antihyperglycemic, and antioxidant activities; meanwhile, it is also effective in the protection of inflammatory bowel disease (IBD), but the specific mechanisms remain unclear. Here, we evaluated the anti-inflammatory of SA and investigated its potential therapeutic activity in LPS-induced intestinal epithelial barrier and tight junction (TJ) protein dysfunction. SA improved cell viability; attenuated epithelial permeability; restored the protein and mRNA expression of claudin-1, ZO-1, and occludin; and reversed the redistribution of the ZO-1 and claudin-1 proteins in LPS-treated Caco-2 cells. Moreover, SA reduced the inflammatory response by downregulating the activation of the TLR4/NF-κB pathway and attenuated LPS-induced intestinal barrier dysfunction by decreasing the activation of the MLCK/MLC pathway. This study demonstrated that SA has strong anti-inflammatory activity and can alleviate the occurrence of high intercellular permeability in Caco-2 cells exposed to LPS.


Assuntos
Ácidos Cumáricos/farmacologia , Mucosa Intestinal/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Transporte Ativo do Núcleo Celular , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Células CACO-2 , Sobrevivência Celular , Claudina-1/biossíntese , Progressão da Doença , Relação Dose-Resposta a Droga , Humanos , Inflamação , Lipopolissacarídeos/metabolismo , Ocludina/biossíntese , Permeabilidade , Junções Íntimas/metabolismo , Proteína da Zônula de Oclusão-1/biossíntese
18.
Europace ; 21(9): 1410-1421, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31106349

RESUMO

AIMS: Brugada syndrome (BrS) is associated with a pronounced risk to develop sudden cardiac death (SCD). Up to 21% of patients are related to mutations in SCN5A. Studies identified SCN10A as a contributor of BrS. However, the investigation of the human cellular phenotype of BrS in the presence of SCN10A mutations remains lacking. The objective of this study was to establish a cellular model of BrS in presence of SCN10A mutations using human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). METHODS AND RESULTS: Dermal fibroblasts obtained from a BrS patient suffering from SCD harbouring the SCN10A double variants (c.3803G>A and c.3749G>A) and three independent healthy control subjects were reprogrammed to hiPSCs. Human-induced pluripotent stem cells were differentiated into cardiomyocytes (hiPSC-CMs).The hiPSC-CMs from the BrS patient showed a significantly reduced peak sodium channel current (INa) and a significantly reduced ATX II (sea anemone toxin, an enhancer of late INa) sensitive as well as A-887826 (a blocker of SCN10A channel) sensitive late sodium channel current (INa) when compared with the healthy control hiPSC-CMs, indicating loss-of-function of sodium channels. Consistent with reduced INa the action potential amplitude and upstroke velocity (Vmax) were significantly reduced, which may contribute to arrhythmogenesis of BrS. Moreover, Ajmaline effects on action potentials were stronger in BrS-hiPSC-CMs than in healthy control cells. This is in agreement with the higher susceptibility of patients to sodium channel blocking drugs in unmasking BrS. CONCLUSION: Patient-specific hiPSC-CMs are able to recapitulate single-cell phenotype features of BrS with SCN10A mutations and may provide novel opportunities to further elucidate the cellular disease mechanism.


Assuntos
Potenciais de Ação/fisiologia , Síndrome de Brugada/genética , Miócitos Cardíacos/metabolismo , Canal de Sódio Disparado por Voltagem NAV1.8/genética , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/genética , Ajmalina/farmacologia , Síndrome de Brugada/metabolismo , Cardiotônicos/farmacologia , Estudos de Casos e Controles , Técnicas de Reprogramação Celular , Venenos de Cnidários/farmacologia , Morte Súbita Cardíaca , Humanos , Células-Tronco Pluripotentes Induzidas , Mutação com Perda de Função , Masculino , Pessoa de Meia-Idade , Morfolinas/farmacologia , Mutação , Miócitos Cardíacos/efeitos dos fármacos , Canal de Sódio Disparado por Voltagem NAV1.8/metabolismo , Niacinamida/análogos & derivados , Niacinamida/farmacologia , Técnicas de Patch-Clamp , Fenótipo , Taquicardia Ventricular , Bloqueadores do Canal de Sódio Disparado por Voltagem/farmacologia
19.
Biotechnol Lett ; 41(6-7): 641-650, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30993481

RESUMO

Cancer is a complex multifactorial disease for which many promising therapeutic strategies such as immunotherapy are emerging. Malignant cells frequently express aberrant cell surface carbohydrates, which differentiate them from normal "healthy" cells. This characteristic presents a window for the development of synthetic carbohydrate antigen-based cancer vaccines which can be recognized by the immune system and can bring about T cell-dependent immune responses. Antibodies generated against the carbohydrate antigens partake in the inactivation of carbohydrate-decorated cancer cells, by slowing down tumor cell growth and inducing cancer cell apoptosis. Novel synthetic strategies for carbohydrate antigens have led to several synthetic cancer vaccine candidates. In the present review, we describe the latest progress in carbohydrate-based cancer vaccines and their clinical evaluation in various cancers.


Assuntos
Antígenos Glicosídicos Associados a Tumores/imunologia , Vacinas Anticâncer/imunologia , Carboidratos/imunologia , Descoberta de Drogas/tendências , Neoplasias/terapia , Vacinas Anticâncer/administração & dosagem , Carboidratos/administração & dosagem , Humanos , Imunidade Celular , Imunidade Humoral
20.
Europace ; 20(FI1): f46-f56, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29566126

RESUMO

Aims: Our aim is to investigate the arrhythmogenic mechanism in arrhythmogenic right ventricular cardiomyopathy (ARVC)-patients by using human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). Methods and results: Human-induced pluripotent stem cell-derived cardiomyocytes were generated from human skin fibroblasts of two healthy donors and an ARVC-patient with a desmoglein-2 (DSG2) mutation. Patch clamp, quantitative polymerase chain reaction, and calcium imaging techniques were employed for the study. The amplitude and maximal upstroke velocity (Vmax) of action potential (AP) in ARVC-cells were smaller than that in healthy donor cells, whereas the resting potential and AP duration (APD) was not changed. The reduced Vmax resulted from decreased peak sodium current. The reason for undetected changes in APD may be the counter-action of reduced transient outward, small conductance Ca2+-activated, adenosine triphosphate-sensitive, Na/Ca exchanger (INCX) currents, and enhanced rapidly delayed rectifier currents. Isoprenaline (Iso) reduced INCX and shortened APD in both donor and ARVC-hiPSC-CMs. However, the effects of Iso in ARVC-cells are significantly larger than that in donor cells. In addition, ARVC-hiPSC-CMs showed more frequently than donor cells arrhythmogenic events induced by adrenergic stimulation. Conclusion: Cardiomyocytes derived from the ARVC patient with a DSG2 mutation displayed multiple ion channel dysfunctions and abnormal cellular electrophysiology as well as enhanced sensitivity to adrenergic stimulation. These may underlie the arrhythmogenesis in ARVC patients.


Assuntos
Potenciais de Ação , Displasia Arritmogênica Ventricular Direita/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Miócitos Cardíacos/metabolismo , Potenciais de Ação/efeitos dos fármacos , Agonistas Adrenérgicos beta/farmacologia , Displasia Arritmogênica Ventricular Direita/genética , Displasia Arritmogênica Ventricular Direita/patologia , Displasia Arritmogênica Ventricular Direita/fisiopatologia , Sinalização do Cálcio , Estudos de Casos e Controles , Células Cultivadas , Canais de Potássio de Retificação Tardia/metabolismo , Desmogleína 2/genética , Desmogleína 2/metabolismo , Predisposição Genética para Doença , Frequência Cardíaca , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/patologia , Isoproterenol/farmacologia , Cinética , Masculino , Pessoa de Meia-Idade , Mutação , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Fenótipo , Trocador de Sódio e Cálcio/metabolismo
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