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Synaptic vesicles are organelles with a precisely defined protein and lipid composition1,2, yet the molecular mechanisms for the biogenesis of synaptic vesicles are mainly unknown. Here we discovered a well-defined interface between the synaptic vesicle V-ATPase and synaptophysin by in situ cryo-electron tomography and single-particle cryo-electron microscopy of functional synaptic vesicles isolated from mouse brains3. The synaptic vesicle V-ATPase is an ATP-dependent proton pump that establishes the proton gradient across the synaptic vesicle, which in turn drives the uptake of neurotransmitters4,5. Synaptophysin6 and its paralogues synaptoporin7 and synaptogyrin8 belong to a family of abundant synaptic vesicle proteins whose function is still unclear. We performed structural and functional studies of synaptophysin-knockout mice, confirming the identity of synaptophysin as an interaction partner with the V-ATPase. Although there is little change in the conformation of the V-ATPase upon interaction with synaptophysin, the presence of synaptophysin in synaptic vesicles profoundly affects the copy number of V-ATPases. This effect on the topography of synaptic vesicles suggests that synaptophysin assists in their biogenesis. In support of this model, we observed that synaptophysin-knockout mice exhibit severe seizure susceptibility, suggesting an imbalance of neurotransmitter release as a physiological consequence of the absence of synaptophysin.
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Sinaptofisina , ATPases Vacuolares Próton-Translocadoras , Animais , Masculino , Camundongos , Microscopia Crioeletrônica , Camundongos Knockout , Modelos Moleculares , Neurotransmissores/metabolismo , Ligação Proteica , Convulsões/genética , Convulsões/metabolismo , Vesículas Sinápticas/química , Vesículas Sinápticas/enzimologia , Vesículas Sinápticas/ultraestrutura , Sinaptofisina/química , Sinaptofisina/deficiência , Sinaptofisina/metabolismo , Sinaptofisina/ultraestrutura , ATPases Vacuolares Próton-Translocadoras/análise , ATPases Vacuolares Próton-Translocadoras/química , ATPases Vacuolares Próton-Translocadoras/metabolismo , ATPases Vacuolares Próton-Translocadoras/ultraestrutura , Tomografia com Microscopia EletrônicaRESUMO
Background: The role of Aspergillus-specific IgG antibody test in the diagnosis of non-neutropenic invasive pulmonary aspergillosis (IPA) is still uncertain, and related studies are also limited. Purpose: This study aims to evaluate the quantitative test value of Aspergillus fumigatus-specific IgG antibody in non-neutropenic IPA, which could provide additional evidence for related clinical diagnosis. Methods: This prospective study collected clinical data of suspected IPA patients from January, 2020 to December, 2022, and patients were divided into two groups, IPA and non-IPA. The study analyzed clinical characteristics and diagnostic value of Aspergillus-specific IgG antibody test, using the receiver operating characteristic (ROC) curve to evaluate diagnostic efficacy. Results: The study enrolled 59 IPA cases and 68 non-IPA cases, the average admission age of IPA group was 63.2±9.6 (33-79), and the gender ratio (male:female) of IPA group was 42:17. The proportion of patients with history of smoking and COPD were higher in IPA group (59.3% vs 39.7%, P=0.027; 33.9% vs 14.7%, P =0.011, respectively). The level of Aspergillus fumigatus-specific IgG antibody in IPA group was significantly higher than non-IPA group (202.1±167.0 vs 62.6±58.0, P<0.001). The area under the ROC curve was 0.799 (95%CI: 0.718, 0.865 P<0.001), and the cut-off with best diagnostic efficacy was 91 AU/mL. Conclusion: Immunological test plays an important role in the diagnosis of pulmonary aspergillosis, and Aspergillus-specific IgG antibody test has the good diagnostic value in non-neutropenic IPA.
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BACKGROUND: Endovenous radiofrequency ablation (RFA) and laser ablation (LA) have been commonly used for treating lower extremity varicose veins (LEVVs). Their therapeutic effects have been widely recognized compared with conventional surgery. However, there have been some controversies regarding the choice between RFA and LA. The objective of our study was to conduct a systematic review and meta-analysis comparing the early and long-term outcomes of RFA and LA. METHODS: A comprehensive search was performed in the PubMed, Embase, and Cochrane databases to identify relevant literature on endovenous thermal ablation for primary LEVV up until June 2023. Randomized controlled trials, cohort studies, and case-control studies involving RFA and LA for LEVV treatment were included. The primary endpoints were the occlusion rate of the great saphenous vein (GSV) and occurrence of venous thrombotic events. Secondary outcomes included nerve injury, hyperpigmentation, burns, recurrence of VVs, postoperative pain, and phlebitis. Data were analyzed using Review Manager 5.3 software. RESULTS: A total of 29 studies met the inclusion criteria, consisting of 16 randomized controlled trials and 13 cohort studies. At 1 month, the occlusion rates of GSV were 98.35% for RFA and 98.04% for LA, whereas at 1 year, the rates were 93.13% for RFA and 94.18% for LA. Subgroup analyses revealed that RFA had higher GSV occlusion rates at 1 year since 2016 (93.27% vs 91.24%; odds ratio [OR], 1.35; 95% confidence interval [CI], 1.0-1.83; P = .05). The incidence of postoperative venous thrombotic events was 0.78% for RFA and 0.87% for LA at 1 month (OR, 1.46; 95% CI, 0.77-2.74; P = .24). RFA showed a reduced risk of burns and ecchymosis (OR, 0.65; 95% CI, 0.48-0.87; P = .005), postprocedural pain (mean difference, -0.85; 95% CI, -1.06 to -0.64; P < .001), recurrence of VVs (OR, 0.58; 95% CI, 0.36-0.92; P = .02), and paresthesia since 2016 (OR, 0.42; 95% CI, 0.19-0.91; P = .03), but an increased risk of skin pigmentation (OR, 1.75; 95% CI, 1.06-2.9; P = .03) compared with LA therapy. The rate of phlebitis was similar between RFA and LA (OR, 0.87; 95% CI, 0.33-2.27; P = .78). CONCLUSIONS: RFA and LA demonstrated similar efficacy in terms of early and long-term occlusion rates of GSV and the incidence of thrombotic and phlebitis complications. However, since 2016, RFA has shown higher GSV occlusion rates compared with LA. Furthermore, RFA was associated with fewer complications such as paresthesia, burns and ecchymosis, and recurrence of VVs when compared with LA.
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Procedimentos Endovasculares , Terapia a Laser , Varizes , Humanos , Varizes/cirurgia , Varizes/diagnóstico por imagem , Terapia a Laser/efeitos adversos , Resultado do Tratamento , Procedimentos Endovasculares/efeitos adversos , Recidiva , Extremidade Inferior/irrigação sanguínea , Ablação por Radiofrequência/efeitos adversos , Feminino , Fatores de Risco , Masculino , Complicações Pós-Operatórias/etiologia , Pessoa de Meia-Idade , Fatores de Tempo , Adulto , Veia Safena/cirurgia , Veia Safena/diagnóstico por imagemRESUMO
BACKGROUND: MRI-based tumor shrinkage patterns (TSP) after neoadjuvant therapy (NAT) have been associated with pathological response. However, the understanding of TSP after early NAT remains limited. We aimed to analyze the relationship between TSP after early NAT and pathological response after therapy in different molecular subtypes. METHODS: We prospectively enrolled participants with invasive ductal breast cancers who received NAT and performed pretreatment DCE-MRI from September 2020 to August 2022. Early-stage MRIs were performed after the first (1st-MRI) and/or second (2nd-MRI) cycle of NAT. Tumor shrinkage patterns were categorized into four groups: concentric shrinkage, diffuse decrease (DD), decrease of intensity only (DIO), and stable disease (SD). Logistic regression analysis was performed to identify independent variables associated with pathologic complete response (pCR), and stratified analysis according to tumor hormone receptor (HR)/human epidermal growth factor receptor 2 (HER2) disease subtype. RESULTS: 344 participants (mean age: 50 years, 113/345 [33%] pCR) with 345 tumors (1 bilateral) had evaluable 1st-MRI or 2nd-MRI to comprise the primary analysis cohort, of which 244 participants with 245 tumors had evaluable 1st-MRI (82/245 [33%] pCR) and 206 participants with 207 tumors had evaluable 2nd-MRI (69/207 [33%] pCR) to comprise the 1st- and 2nd-timepoint subgroup analysis cohorts, respectively. In the primary analysis, multivariate analysis showed that early DD pattern (OR = 12.08; 95% CI 3.34-43.75; p < 0.001) predicted pCR independently of the change in tumor size (OR = 1.37; 95% CI 0.94-2.01; p = 0.106) in HR+/HER2- subtype, and the change in tumor size was a strong pCR predictor in HER2+ (OR = 1.61; 95% CI 1.22-2.13; p = 0.001) and triple-negative breast cancer (TNBC, OR = 1.61; 95% CI 1.22-2.11; p = 0.001). Compared with the change in tumor size, the SD pattern achieved a higher negative predictive value in HER2+ and TNBC. The statistical significance of complete 1st-timepoint subgroup analysis was consistent with the primary analysis. CONCLUSION: The diffuse decrease pattern in HR+/HER2- subtype and stable disease in HER2+ and TNBC after early NAT could serve as additional straightforward and comprehensible indicators of treatment response. TRIAL REGISTRATION: Trial registration at https://www.chictr.org.cn/ . REGISTRATION NUMBER: ChiCTR2000038578, registered September 24, 2020.
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Neoplasias da Mama , Neoplasias de Mama Triplo Negativas , Humanos , Pessoa de Meia-Idade , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias de Mama Triplo Negativas/diagnóstico por imagem , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Terapia Neoadjuvante , Resultado do Tratamento , Receptor ErbB-2/genética , Imageamento por Ressonância Magnética , Valor Preditivo dos Testes , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Estudos RetrospectivosRESUMO
Chimeric antigen receptor (CAR) T cell therapies have successfully treated hematological malignancies. Macrophages have also gained attention as an immunotherapy owing to their immunomodulatory capacity and ability to infiltrate solid tumors and phagocytize tumor cells. The first-generation CD3ζ-based CAR-macrophages could phagocytose tumor cells in an antigen-dependent manner. Here we engineered induced pluripotent stem cell-derived macrophages (iMACs) with toll-like receptor 4 intracellular toll/IL-1R (TIR) domain-containing CARs resulting in a markedly enhanced antitumor effect over first-generation CAR-macrophages. Moreover, the design of a tandem CD3ζ-TIR dual signaling CAR endows iMACs with both target engulfment capacity and antigen-dependent M1 polarization and M2 resistance in a nuclear factor kappa B (NF-κB)-dependent manner, as well as the capacity to modulate the tumor microenvironment. We also outline a mechanism of tumor cell elimination by CAR-induced efferocytosis against tumor cell apoptotic bodies. Taken together, we provide a second-generation CAR-iMAC with an ability for orthogonal phagocytosis and polarization and superior antitumor functions in treating solid tumors relative to first-generation CAR-macrophages.
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Neoplasias , Receptores de Antígenos Quiméricos , Humanos , Receptores de Antígenos de Linfócitos T , Linfócitos T , Linhagem Celular Tumoral , Receptores de Antígenos Quiméricos/genética , Imunoterapia Adotiva/métodos , Macrófagos/patologia , Microambiente TumoralRESUMO
BACKGROUND: To evaluate the correlation between synthetic MRI (syMRI) relaxometry and apparent diffusion coefficient (ADC) maps in different breast cancer subtypes and treatment response subgroups. METHODS: Two hundred sixty-three neoadjuvant therapy (NAT)-treated breast cancer patients with baseline MRI were enrolled. Tumor annotations were obtained by drawing regions of interest (ROIs) along the lesion on T1/T2/PD and ADC maps respectively. Histogram features from T1/T2/PD and ADC maps were respectively calculated, and the correlation between each pair of identical features was analyzed. Meanwhile, features between different NAT treatment response groups were compared, and their discriminatory power was evaluated. RESULTS: Among all patients, 20 out of 27 pairs of features weakly correlated (r = - 0.13-0.30). For triple-negative breast cancer (TNBC), features from PD map in the pathological complete response (pCR) group (r = 0.60-0.86) showed higher correlation with ADC than that of the non-pCR group (r = 0.30-0.43), and the mean from the ADC and PD maps in the pCR group strongly correlated (r = 0.86). For HER2-positive, few correlations were found both in the pCR and non-pCR groups. For luminal HER2-negative, T2 map correlated more with ADC than T1 and PD maps. Significant differences were seen in T2 low percentiles and median in the luminal-HER2 negative subtype, yielding moderate AUCs (0.68/0.72/0.71). CONCLUSIONS: The relationship between ADC and PD maps in TNBC may indicate different NAT responses. The no-to-weak correlation between the ADC and syMRI suggests their complementary roles in tumor microenvironment evaluation. CRITICAL RELEVANCE STATEMENT: The relationship between ADC and PD maps in TNBC may indicate different NAT responses, and the no-to-weak correlation between the ADC and syMRI suggests their complementary roles in tumor microenvironment evaluation. KEY POINTS: ⢠The relationship between ADC and PD in TNBC indicates different NAT responses. ⢠The no-to-weak correlations between ADC and syMRI complementarily evaluate tumor microenvironment. ⢠T2 low percentiles and median predict NAT response in luminal-HER2-negative subtype.
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BACKGROUND: Primary central nervous system lymphoma (PCNSL) is a non-Hodgkin lymphoma that occurs in the CNS. With the advancement of medical care, its prognosis and treatment have also undergone tremendous changes. This study aimed to construct a prognostic model and compare the effects of different treatments for intracranial PCNSL. METHODS: Cases diagnosed as PCNSL between 2004 and 2015 were obtained from the Surveillance, Epidemiology, and End Results (SEER) database. Data were analyzed using Kaplan-Meier method and Cox regression analysis. Nomogram was built and validated using the R program. RESULTS: A total of 2861 PCNSL patients were included in the analysis. Age, year of diagnosis, surgery and chemotherapy were independent predictors for both overall survival (OS) and cancer-specific survival (CSS). A nomogram was established to predict 3-, 5- and 10-year OS and CSS for patients. Receiver operating characteristic (ROC) curves and decision curve analysis (DCA) showed the nomogram had good predictive performance and clinical application value. We also revealed that gross total resection had significantly better OS and CSS than biopsy alone (P < 0.001). Patients who received only chemotherapy had the best prognosis and did not benefit from additional radiotherapy. CONCLUSION: We developed a nomogram to predict patient survival rates based on independent predictors. It is an effective tool to help clinicians make survival predictions. Our results showed that patients can benefit from gross total resection of tumor, if it is feasible, and chemotherapy. The role of radiotherapy remained to be further assessed.
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Chinese chestnut shell is a by-product of chestnut food processing and is rich in polyphenols. This study sought to investigate the effect of chestnut shell polyphenol extract (CSP) on weight loss and lipid reduction in a 12-week high-fat diet (HFD)-induced murine obesity model. CSP (300 mg per kg body weight) was administered intragastrically daily. AG490, a JAK2 protein tyrosine kinase inhibitor, was also intraperitoneally injected. The results showed that an HFD induced leptin resistance (LR). Compared to corresponding values in the HFD group, CSP treatment improved blood lipid levels, weight, and leptin levels in obese mice (p < 0.01). Additionally, CSP treatment enhanced enzyme activity by improving total antioxidant capacity, attenuating oxidative stress, and reducing fat droplet accumulation and inflammation in the liver, epididymal, and retroperitoneal adipose tissue. CSP also activated the LEPR-JAK2/STAT3-PTP1B-SOCS-3 signal transduction pathway in hypothalamus tissue and improved LR while regulating the expression of proteins related to lipid metabolism (PPARγ, FAS, and LPL) in white adipose tissue in the retroperitoneal cavity. However, the amelioration of lipid metabolism by CSP was dependent on JAK2. Molecular docking simulation further demonstrated the strong binding affinity of procyanidin C1 (-10.3983297 kcal mol-1) and procyanidin B1 (-9.12686729 kcal mol-1) to the crystal structure of JAK2. These results suggest that CSP may be used to reduce HFD-induced obesity with potential application as a functional food additive.
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Dieta Hiperlipídica , Leptina , Animais , Camundongos , Dieta Hiperlipídica/efeitos adversos , Fagaceae , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Leptina/metabolismo , Lipídeos , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Nozes , Obesidade/metabolismo , Extratos Vegetais , Estruturas Vegetais , Polifenóis/farmacologia , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismoRESUMO
The water-selective channel protein aquaporin-4 (AQP4) contributes to the migration and proliferation of gliomas, and to their resistance to therapy. Here we show, in glioma cell cultures, in subcutaneous and orthotopic gliomas in rats, and in glioma tumours in patients, that transmembrane water-efflux rate is a sensitive biomarker of AQP4 expression and can be measured via conventional dynamic-contrast-enhanced magnetic resonance imaging. Water-efflux rates correlated with stages of glioma proliferation as well as with changes in the heterogeneity of intra-tumoural and inter-tumoural AQP4 in rodent and human gliomas following treatment with temozolomide and with the AQP4 inhibitor TGN020. Regions with low water-efflux rates contained higher fractions of stem-like slow-cycling cells and therapy-resistant cells, suggesting that maps of water-efflux rates could be used to identify gliomas that are resistant to therapies.
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Glioma , Água , Humanos , Ratos , Animais , Água/metabolismo , Glioma/diagnóstico por imagem , Glioma/metabolismo , Aquaporina 4/metabolismo , Biomarcadores , Imageamento por Ressonância MagnéticaRESUMO
Given that COVID-19 continues to wreak havoc around the world, it is imperative to search for a conserved region involved in viral infection so that effective vaccines can be developed to prevent the virus from rapid mutations. We have established a twelve-fragment library of recombinant proteins covering the entire region of spike protein of both SARS-CoV-2 and SARS-CoV from Escherichia coli. IgGs from murine antisera specifically against 6 spike protein fragments of SARS-CoV-2 were produced, purified, and characterized. We found that one specific IgG against the fusion process region, named COVID19-SF5, serologically cross-reacted with all twelve S-protein fragments. COVID19-SF5, with amino acid sequences from 880 to 1084, specifically bound to VERO-E6 and BEAS-2B cells, with Kd values of 449.1 ± 21.41 and 381.9 ± 31.53 nM, and IC50 values of 761.2 ± 28.2 nM and 862.4 ± 32.1 nM, respectively. In addition, COVID19-SF5 greatly enhanced binding of the full-length CHO cell-derived spike protein to the host cells in a concentration-dependent manner. Furthermore, COVID19-SF5 and its IgGs inhibited the infection of the host cells by pseudovirus. The combined data from our studies reveal that COVID19-SF5, a novel cell-binding fragment, may contain a common region(s) for mediating viral binding during infection. Our studies also provide valuable insights into how virus variants may evade host immune recognition. Significantly, the observation that the IgGs against COVID19-SF5 possesses cross reactivity to all other fragments of S protein, suggesting that it is possible to develop universal neutralizing monoclonal antibodies to curb rapid mutations of COVID-19.
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COVID-19 , SARS-CoV-2 , Animais , Anticorpos Monoclonais , Anticorpos Antivirais , Soros Imunes , Imunoglobulina G , Glicoproteínas de Membrana/química , Camundongos , Proteínas Recombinantes/genética , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Proteínas do Envelope ViralRESUMO
Improvements in cryo-electron tomography sample preparation, electron-microscopy instrumentations, and image processing algorithms have advanced the structural analysis of macromolecules in situ. Beyond such analyses of individual macromolecules, the study of their interactions with functionally related neighbors in crowded cellular habitats, i.e. 'molecular sociology', is of fundamental importance in biology. Here we present a NEighboring Molecule TOpology Clustering (NEMO-TOC) algorithm. We optimized this algorithm for the detection and profiling of polyribosomes, which play both constitutive and regulatory roles in gene expression. Our results suggest a model where polysomes are formed by connecting multiple nonstochastic blocks, in which translation is likely synchronized.
Improvements in cryo-electron tomography sample preparation, electron-microscopy instrumentations, and image processing algorithms have advanced the structural analysis of macromolecules in situ. Beyond such analyses of individual macromolecules, the study of their interactions with functionally related neighbors in crowded cellular habitats, i.e. "molecular sociology", is of fundamental importance in biology. Here we present a NEighboring Molecule TOpology Clustering (NEMO-TOC) algorithm. We optimized this algorithm for the detection and profiling of polyribosomes, which play both constitutive and regulatory roles in gene expression. Our results suggest a model where polysomes are formed by connecting multiple nonstochastic blocks, in which translation is likely synchronized.
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Algoritmos , Tomografia com Microscopia Eletrônica , Polirribossomos/ultraestrutura , Análise por Conglomerados , Microscopia Crioeletrônica , Tomografia com Microscopia Eletrônica/métodos , Substâncias Macromoleculares/químicaRESUMO
Vascular calcification (VC) is the most widespread pathological change in diseases of the vascular system. However, we do not have a good understanding of the molecular mechanisms and effective therapeutic approaches for VC. Curcumin (CUR) is a natural polyphenolic compound that has hypolipidemic, anti-inflammatory, and antioxidant effects on the cardiovascular system. Exosomes are known to have extensive miRNAs for intercellular regulation. This study investigated whether CUR attenuates VC by affecting the secretion of exosomal miRNAs. Calcification models were established in vivo and in vitro using vitamin D3 and ß-glycerophosphate, respectively. Appropriate therapeutic concentrations of CUR were detected on vascular smooth muscle cells (VSMCs) using a cell counting kit 8. Exosomes were extracted by super speed centrifugation from the supernatant of cultured VSMCs and identified by transmission electron microscopy and particle size analysis. Functional and phenotypic experiments were performed in vitro to verify the effects of CUR and exosomes secreted by VSMCs treated with CUR on calcified VSMCs. Compared with the calcified control group, both CUR and exosomes secreted by VSMCs after CUR intervention attenuated calcification in VSMCs. Real-Time quantitative PCR (RT-qPCR) experiments showed that miR-92b-3p, which is important for alleviating VC, was expressed highly in both VSMCs and exosomes after CUR intervention. The mimic miR-92b-3p significantly decreased the expression of transcription factor KLF4 and osteogenic factor RUNX2 in VSMCs, while the inhibitor miR-92b-3p had the opposite effect. Based on bioinformatics databases and dual luciferase experiments, the prospective target of miR-92b-3p was determined to be KLF4. Both mRNA and protein of RUNX2 were decreased and increased in VSMCs by inhibiting and overexpressing of KLF4, respectively. In addition, in the rat calcification models, CUR attenuated vitamin D3-induced VC by increasing miR-92b-3p expression and decreasing KLF4 expression in the aorta. In conclusion, our study suggests that CUR attenuates vascular calcification via the exosomal miR-92b-3p/KLF4 axis.
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Curcumina , MicroRNAs , Calcificação Vascular , Animais , Antioxidantes/farmacologia , Colecalciferol/farmacologia , Subunidade alfa 1 de Fator de Ligação ao Core , Curcumina/farmacologia , MicroRNAs/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , RNA Mensageiro/metabolismo , Ratos , Calcificação Vascular/tratamento farmacológico , Calcificação Vascular/metabolismoRESUMO
Animals constantly receive various sensory stimuli, such as odours, sounds, light and touch, from the surrounding environment. These sensory inputs are essential for animals to search for food and avoid predators, but they also affect their physiological status, and may cause diseases such as cancer. Malignant gliomas-the most lethal form of brain tumour1-are known to intimately communicate with neurons at the cellular level2,3. However, it remains unclear whether external sensory stimuli can directly affect the development of malignant glioma under normal living conditions. Here we show that olfaction can directly regulate gliomagenesis. In an autochthonous mouse model that recapitulates adult gliomagenesis4-6 originating in oligodendrocyte precursor cells (OPCs), gliomas preferentially emerge in the olfactory bulb-the first relay of brain olfactory circuitry. Manipulating the activity of olfactory receptor neurons (ORNs) affects the development of glioma. Mechanistically, olfaction excites mitral and tufted (M/T) cells, which receive sensory information from ORNs and release insulin-like growth factor 1 (IGF1) in an activity-dependent manner. Specific knockout of Igf1 in M/T cells suppresses gliomagenesis. In addition, knocking out the IGF1 receptor in pre-cancerous mutant OPCs abolishes the ORN-activity-dependent mitogenic effects. Our findings establish a link between sensory experience and gliomagenesis through their corresponding sensory neuronal circuits.
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Carcinogênese , Glioma , Fator de Crescimento Insulin-Like I , Neurônios Receptores Olfatórios , Olfato , Animais , Glioma/metabolismo , Glioma/patologia , Camundongos , Vias Neurais , Bulbo Olfatório/patologia , Neurônios Receptores Olfatórios/fisiologia , Olfato/fisiologiaRESUMO
The age-dependent decline in remyelination potential of the central nervous system during ageing is associated with a declined differentiation capacity of oligodendrocyte progenitor cells (OPCs). The molecular players that can enhance OPC differentiation or rejuvenate OPCs are unclear. Here we show that, in mouse OPCs, nuclear entry of SIRT2 is impaired and NAD+ levels are reduced during ageing. When we supplement ß-nicotinamide mononucleotide (ß-NMN), an NAD+ precursor, nuclear entry of SIRT2 in OPCs, OPC differentiation, and remyelination were rescued in aged animals. We show that the effects on myelination are mediated via the NAD+-SIRT2-H3K18Ac-ID4 axis, and SIRT2 is required for rejuvenating OPCs. Our results show that SIRT2 and NAD+ levels rescue the aged OPC differentiation potential to levels comparable to young age, providing potential targets to enhance remyelination during ageing.
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Células Precursoras de Oligodendrócitos , Remielinização , Envelhecimento , Animais , Diferenciação Celular/fisiologia , Células Cultivadas , Camundongos , Bainha de Mielina , NAD , Células Precursoras de Oligodendrócitos/fisiologia , Oligodendroglia/fisiologia , Remielinização/fisiologia , Sirtuína 2/genéticaRESUMO
Mounting evidence supports that oligodendrocyte precursor cells (OPCs) play important roles in maintaining the integrity of normal brains, and that their dysfunction is the etiology of numerous severe neurological diseases. OPCs exhibit diverse heterogeneity in the adult brain, and distinct germinal zones of the embryonic brain contribute to OPC genesis. However, it remains obscure whether developmental origins shape OPC heterogeneity in the adult brain. Here, an in vivo clonal analysis approach is developed to address this. By combining OPC-specific transgenes, in utero electroporation, and the PiggyBac transposon system, the lineages of individual neonatal OPCs derived from either dorsal or ventral embryonic germinal zones are traced, and the landscape of their trajectories is comprehensively described throughout development. Surprisingly, despite behaving indistinguishably in the brain before weaning, dorsally derived OPCs continuously expand throughout life, but ventrally derived OPCs eventually diminish. Importantly, clonal analysis supports the existence of an intrinsic cellular "clock" to control OPC expansion. Moreover, knockout of NF1 could circumvent the distinction of ventrally derived OPCs in the adult brain. Together, this work shows the importance of in vivo clonal analysis in studying stem/progenitor cell heterogeneity, and reveals that developmental origins play a role in determining OPC fate.
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Encéfalo/metabolismo , Linhagem da Célula/genética , Evolução Clonal/genética , Heterogeneidade Genética , Células Precursoras de Oligodendrócitos/metabolismo , Animais , Animais Recém-Nascidos , Encéfalo/crescimento & desenvolvimento , Sistemas CRISPR-Cas/genética , Contagem de Células , Diferenciação Celular/genética , Células Cultivadas , Elementos de DNA Transponíveis/genética , Eletroporação , Humanos , Camundongos , Oligodendroglia/metabolismo , Células-Tronco/metabolismoRESUMO
Arterial calcification refers to the abnormal deposition of calcium salts in the arterial wall, which results in vessel lumen stenosis and vascular remodeling. Studies increasingly show that arterial calcification is a cell mediated, reversible and active regulated process similar to physiological bone mineralization. The osteoblasts and chondrocytes-like cells are present in large numbers in the calcified lesions, and express osteogenic transcription factor and bone matrix proteins that are known to initiate and promote arterial calcification. In addition, osteoclast-like cells have also been detected in calcified arterial walls wherein they possibly inhibit vascular calcification, similar to the catabolic process of bone mineral resorption. Therefore, tilting the balance between osteoblast-like and osteoclast-like cells to the latter maybe a promising therapeutic strategy against vascular calcification. In this review, we have summarized the current findings on the origin and functions of osteoblast-like and osteoclast-like cells in the development and progression of vascular progression, and explored novel therapeutic possibilities.
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Glioblastoma is the most malignant cancer in the brain and currently incurable. It is urgent to identify effective targets for this lethal disease. Inhibition of such targets should suppress the growth of cancer cells and, ideally also precancerous cells for early prevention, but minimally affect their normal counterparts. Using genetic mouse models with neural stem cells (NSCs) or oligodendrocyte precursor cells (OPCs) as the cells-of-origin/mutation, it is shown that the susceptibility of cells within the development hierarchy of glioma to the knockout of insulin-like growth factor I receptor (IGF1R) is determined not only by their oncogenic states, but also by their cell identities/states. Knockout of IGF1R selectively disrupts the growth of mutant and transformed, but not normal OPCs, or NSCs. The desirable outcome of IGF1R knockout on cell growth requires the mutant cells to commit to the OPC identity regardless of its development hierarchical status. At the molecular level, oncogenic mutations reprogram the cellular network of OPCs and force them to depend more on IGF1R for their growth. A new-generation brain-penetrable, orally available IGF1R inhibitor harnessing tumor OPCs in the brain is also developed. The findings reveal the cellular window of IGF1R targeting and establish IGF1R as an effective target for the prevention and treatment of glioblastoma.
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BACKGROUND: Vascular calcification (VC) is a common pathological lesion that promotes progress and mortality in cardiovascular disease. Vascular smooth muscle cells (VSMCs) acquiring an osteogenic phenotype facilitate VC occurrence and development. We recently reported that miR-29b-3p directly regulates the expression of matrix metalloproteinase 2 (MMP2). Herein, we test whether miR-29b-3p functions in the phenotypic transition and calcification in a calcified environment. METHODS AND RESULTS: VSMC calcification in vitro was induced with calcification medium containing ß-glycerophosphoric acid or high calcium. MiR-29b-3p expression in VSMCs tended to decrease during culturing in calcification medium. MiR-29b-3p overexpression ameliorated VSMC calcification, whereas miR-29b-3p knockdown exacerbated VSMC calcification. Furthermore, ectopic expression of miR-29b-3p inhibited the expression of osteogenic markers and MMP2 (a known target gene of miR-29b-3p). By contrast, miR-29b-3p deficiency facilitated VSMC osteogenesis differentiation and upregulated MMP2 expression. CONCLUSION: Our research suggests that miR-29b-3p regulates VSMC calcification and osteogenesis differentiation, at least in part, by targeting MMP2. Regulation of miR-29b-3p expression is therefore a potential therapeutic target for VSMC calcification.
Assuntos
Cálcio/metabolismo , Transdiferenciação Celular , Metaloproteinase 2 da Matriz/metabolismo , MicroRNAs/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Calcificação Vascular/metabolismo , Animais , Cálcio/farmacologia , Linhagem Celular , Metaloproteinase 2 da Matriz/genética , MicroRNAs/genética , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/patologia , Ratos , Calcificação Vascular/genética , Calcificação Vascular/patologiaRESUMO
BACKGROUND The aim of this study was to investigate whether PP2A activation is involved in the anti-cancer activity of metformin. MATERIAL AND METHODS A549 and H1651 human lung cancer cells were constructed with stable a4 overexpression (O/E α4) or knockdown of PP2A catalytic subunit A/B(sh-PP2Ac). Influences of okadaic acid (OA) treatment, O/E α4 or sh-PP2Ac on metformin treated cells were investigated by cell viability, proliferation, apoptosis, and Transwell invasion assay in vitro. Protein expression levels of Bax, Bcl-2, Myc, and Akt as well as serine phosphorylation level of Bax, Myc, and Akt were examined by western blot. For in vivo assays, wild type (WT) or modified A549 cells were subcutaneously injected in nude mice, and metformin treatment on these xenografted tumors were assayed by tumor formation assay and western blot detecting cell proliferation marker PCNA (proliferating cell nuclear antigen) as well as protein expression level and serine phosphorylation level of Akt and Myc. RESULTS Metformin treatment significantly reduced A549 or H1651 cell growth and invasive capacity in vitro as well as Ser184 phosphorylation of Bax, Ser62 phosphorylation of Myc, and Ser473 phosphorylation of Akt, all of which could be partially attenuated by OA treatment, O/E α4 or sh-PP2Ac. Metformin treatment also significantly reduced tumor formation in vivo as well as protein expression of PCNA, Akt, Myc, and serine phosphorylation of the latter 2, which can be partially blocked by O/E α4 or sh-PP2Ac. CONCLUSIONS Metformin reduced lung cancer cell growth and invasion in vitro as well as tumor formation in vivo partially by activating PP2A.