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1.
Nature ; 603(7899): 159-165, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35197629

RESUMO

Metformin, the most prescribed antidiabetic medicine, has shown other benefits such as anti-ageing and anticancer effects1-4. For clinical doses of metformin, AMP-activated protein kinase (AMPK) has a major role in its mechanism of action4,5; however, the direct molecular target of metformin remains unknown. Here we show that clinically relevant concentrations of metformin inhibit the lysosomal proton pump v-ATPase, which is a central node for AMPK activation following glucose starvation6. We synthesize a photoactive metformin probe and identify PEN2, a subunit of γ-secretase7, as a binding partner of metformin with a dissociation constant at micromolar levels. Metformin-bound PEN2 forms a complex with ATP6AP1, a subunit of the v-ATPase8, which leads to the inhibition of v-ATPase and the activation of AMPK without effects on cellular AMP levels. Knockout of PEN2 or re-introduction of a PEN2 mutant that does not bind ATP6AP1 blunts AMPK activation. In vivo, liver-specific knockout of Pen2 abolishes metformin-mediated reduction of hepatic fat content, whereas intestine-specific knockout of Pen2 impairs its glucose-lowering effects. Furthermore, knockdown of pen-2 in Caenorhabditis elegans abrogates metformin-induced extension of lifespan. Together, these findings reveal that metformin binds PEN2 and initiates a signalling route that intersects, through ATP6AP1, the lysosomal glucose-sensing pathway for AMPK activation. This ensures that metformin exerts its therapeutic benefits in patients without substantial adverse effects.


Assuntos
Hipoglicemiantes , Metformina , ATPases Vacuolares Próton-Translocadoras , Proteínas Quinases Ativadas por AMP/metabolismo , Adenosina Trifosfatases/metabolismo , Secretases da Proteína Precursora do Amiloide , Animais , Caenorhabditis elegans/metabolismo , Diabetes Mellitus/tratamento farmacológico , Glucose/metabolismo , Humanos , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/metabolismo , Hipoglicemiantes/farmacologia , Lisossomos/metabolismo , Proteínas de Membrana , Metformina/agonistas , Metformina/metabolismo , Metformina/farmacologia , ATPases Vacuolares Próton-Translocadoras/metabolismo
2.
Oncologist ; 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38478404

RESUMO

BACKGROUND: This study aimed to compare the survival outcomes of patients with initially unresectable hepatocellular carcinoma (HCC) and portal vein tumor thrombus (PVTT) who underwent or did not undergo salvage surgery followed by a triple combination conversion treatment consisted of locoregional treatment (LRT), tyrosine kinase inhibitors (TKIs), and anti-PD-1 antibodies. METHODS: The data from 93 consecutive patients with initially unresectable HCC and PVTT across 4 medical centers were retrospectively reviewed. They were converted successfully by the triple combination treatment and underwent or did not undergo salvage resection. The baseline characteristics, conversion schemes, conversion treatment-related adverse events (CTRAEs), overall survival (OS), and progression-free survival (PFS) of the salvage surgery and non-surgery groups were compared. Multivariate Cox regression analysis was performed to identify independent risk factors for OS and PFS. Additionally, subgroup survival analysis was conducted by stratification of degree of tumor response and type of PVTT. RESULTS: Of the 93 patients, 44 underwent salvage surgery, and 49 did not undergo salvage surgery. The OS and PFS of the salvage surgery and non-surgery groups were not significantly different (P = .370 and .334, respectively). The incidence and severity of CTRAEs of the 2 groups were also comparable. Subgroup analyses revealed that for patients with complete response (CR) or types III-IV PVTT, there was a trend toward better survival in patients who did not undergo salvage surgery. Multivariate analysis showed that baseline α-fetoprotein and best tumor response per mRECIST criteria were independent prognostic factors for OS and PFS. CONCLUSIONS: For patients with initially unresectable HCC and PVTT who were successfully converted by the triple combination therapy, salvage liver resection may not be necessary, especially for the patients with CR or types III-IV PVTT.

3.
Small ; : e2401530, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38751307

RESUMO

The unavoidable and unpredictable surface reconstruction of metallic copper (Cu) during the electrocatalytic carbon dioxide (CO2) reduction process is a double-edged sword affecting the production of high-value-added hydrocarbon products. It is crucial to control the surface facet reconstruction and regulate the targeted facets/facet interfaces, and further understand the mechanism between activity/selectivity and the reconstructed structure of Cu for CO2 reduction. Based on the current catalyst design methods, a facile strategy combining chemical reduction and electro-reduction is proposed to achieve specified Cu(111) facets and the Cu(110)/(111) interfaces in reconstructed Cu derived from cuprous oxide (Cu2O). The surface facet reconstruction significantly boosted the electrocatalytic conversion of CO2 into multi-carbon (C2+) products comparing to the unmodified catalyst. Theoretical and experimental analyses show that the Cu(110)/(111)s interface between Cu(110) and a small amount of Cu(111) can tailor the reaction routes and lower the reaction energy barrier of C-C coupling to ethylene (C2H4). The work will guide the surface facets reconstruction strategy for Cu-based CO2 electrocatalysts, providing a promising paradigm to understand the structural variation in catalysts.

4.
Small ; 20(20): e2307129, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38126615

RESUMO

Organic luminescent materials are indispensable in optoelectronic displays and solid-state luminescence applications. Compared with single-component, multi-component crystalline materials can improve optoelectronic characteristics. This work forms a series of full-spectrum tunable luminescent charge-transfer (CT) cocrystals ranging from 400 to 800 nm through intermolecular collaborative self-assembly. What is even more interesting is that o-TCP-Cor(x)-Pe(1-x), p-TCP-Cor(x)-Pe(1-x), and o-TCP-AN(x)-TP(1-x) alloys are prepared based on cocrystals by doping strategies, which correspondingly achieve the stepless color change from blue (CIE [0.22, 0.44]) to green (CIE [0.16, 0.14]), from green (CIE [0.27, 0.56]) to orange (CIE [0.58, 0.42]), from yellow (CIE [0.40, 0.57]) to red (CIE [0.65, 0.35]). The work provides an efficient method for precisely synthesizing new luminescent organic semiconductor materials and lays a solid foundation for developing advanced organic solid-state displays.

5.
J Med Virol ; 96(3): e29512, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38483056

RESUMO

Coronaviruses (CoVs) have continuously posed a threat to human and animal health. However, existing antiviral drugs are still insufficient in overcoming the challenges caused by multiple strains of CoVs. And methods for developing multi-target drugs are limited in terms of exploring drug targets with similar functions or structures. In this study, four rounds of structural design and modification on salinomycin were performed for novel antiviral compounds. It was based on the strategy of similar topological structure binding properties of protein targets (STSBPT), resulting in the high-efficient synthesis of the optimal compound M1, which could bind to aminopeptidase N and 3C-like protease from hosts and viruses, respectively, and exhibit a broad-spectrum antiviral effect against severe acute respiratory syndrome CoV 2 pseudovirus, porcine epidemic diarrhea virus, transmissible gastroenteritis virus, feline infectious peritonitis virus and mouse hepatitis virus. Furthermore, the drug-binding domains of these proteins were found to be structurally similar based on the STSBPT strategy. The compounds screened and designed based on this region were expected to have broad-spectrum and strong antiviral activities. The STSBPT strategy is expected to be a fundamental tool in accelerating the discovery of multiple targets with similar effects and drugs.


Assuntos
Infecções por Coronavirus , Coronavirus , Animais , Gatos , Camundongos , Suínos , Humanos , Antivirais/química , Infecções por Coronavirus/tratamento farmacológico , Inibidores de Proteases/farmacologia , Inibidores de Proteases/química
6.
J Neurooncol ; 166(2): 331-339, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38236548

RESUMO

BACKGROUND: In previous studies, patients with intracranial germ cell tumour (iGCT) with pure choriocarcinoma or mixed germ cell tumours with choriocarcinoma element showed similar dismal prognoses, with median overall survival (OS) of 22 months and 1-year survival rate of approximately 60%. However, these conclusions need to be updated because radiotherapy, which is the mainstay for this disease, was not applied in a number of patients. Additionally, prognostic factors need to be explored in this population. METHODS: Clinical data of patients with iGCTs with histologically confirmed choriocarcinoma element or beta-human chorionic gonadotropin (ß-HCG) > 500 IU/L were collected from the archives of our institution and retrospectively studied. RESULTS: A total of 76 patients were eligible for this study. Except for two early deaths, all patients received radiotherapy (craniospinal irradiation [CSI], n = 23; non-CSI, n = 51). The median follow-up duration for the entire series was 63 months (range, 6-188 months). The 5-year event-free survival (EFS) and OS rates were 81.5% and 84.1%, respectively. Among patients who did not have early death or progressive disease after induction chemotherapy, multivariate analysis revealed that chemotherapy cycles (> 4 vs. ≤ 4) (hazard ratio [HR] for EFS 0.144, p = 0.020; HR for OS 0.111, p = 0.028) and ß-HCG levels (> 3000 IU/L vs. ≤ 3000 IU/L) (HR for EFS 4.342, p = 0.059; HR for OS 6.614, p = 0.033) were independent factors for survival. CONCLUSIONS: Patients with iGCTs with choriocarcinoma element or ß-HCG > 500 IU/L showed improved survival with radiotherapy-based treatments. Additional chemotherapy cycles could result in additional survival benefits. Patients with ß-HCG level > 3000 IU/L had poorer prognosis.


Assuntos
Neoplasias Encefálicas , Coriocarcinoma , Neoplasias Embrionárias de Células Germinativas , Feminino , Humanos , Estudos Retrospectivos , Neoplasias Encefálicas/patologia , Resultado do Tratamento , Neoplasias Embrionárias de Células Germinativas/terapia , Coriocarcinoma/terapia , Coriocarcinoma/metabolismo , Coriocarcinoma/patologia , Fatores de Risco , Gonadotropina Coriônica/metabolismo
7.
J Org Chem ; 89(2): 1353-1360, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38190649

RESUMO

We have developed a visible light-induced intermolecular [2 + 2]-cycloaddition reaction between alkenes and alkynes using thioxanthone and Cu(OTf)2 as cocatalysts. Various quinolin-2(1H)-ones, featuring diverse substituted groups, were successfully employed in this reaction, resulting in the synthesis of a series of 4,8b-dihydrocyclobuta[c]quinolin-3(2aH)-ones. Our methodology presents a novel synthetic approach for alkene-alkyne [2 + 2]-cycloaddition, delivering cyclobutene derivatives with exceptional regioselectivity.

8.
J Phys Chem A ; 128(24): 4830-4837, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38850258

RESUMO

The structure of samoquasine A has long been a subject of controversy, which was resolved only upon its successful total synthesis. We examined the structures of the associated compounds using the state-of-the-art SVM-M protocol. The method accurately discriminated all putative structures historically attributed to samoquasine A from a pool of 48 isomeric structures, confirming that samoquasine A is indeed identical to perlolidine. Furthermore, by applying the SVM-M protocol to an additional pool of 67 isomeric structures, we successfully assigned a yet unknown natural product, initially misidentified as perlolidine, as a novel oxime, (E)-3H-cyclopenta[c]quinolin-3-one oxime, representing the first reported cyclone oxime-quinoline natural product.

9.
Environ Res ; 246: 118069, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38160966

RESUMO

Heavy metals and metalloids (HMMs) inhibit the biodegradation of organic pollutants. The degree of inhibition depends not only on the concentration and bioavailability of HMMs but also on additional factors, such as environmental variables (e.g., inorganic components, organic matter, pH, and redox potential), the nature of the metals, and microbial species. Based on the degradation pattern and metal concentrations causing half biodegradation rate reductions (RC50s), the inhibition of biodegradation was: Hg2+, As2O3 > Cu2+, Cd2+, Pb2+, Cr3+ > Ni2+, Co2+ > Mn2+, Zn2+ > Fe3+. Four patterns were observed: inhibition increases with increasing metal concentration; low concentrations stimulate, while high concentrations inhibit; high concentrations inhibit less; and mild inhibition remains constant. In addition, metal ion mixtures have more complex inhibitory effects on the degradation of organic pollutants, which may be greater than, similar to, or less than that of individual HMMs. Finally, the inhibitory mechanism of HMMs on biodegradation is reviewed. HMMs generally have little impact on the biodegradation pathway of organic pollutants for bacterial strains. However, when pollutants are biodegraded by the community, HMMs may activate microbial populations harbouring different transformation pathways. HMMs can affect the biodegradation efficiency of organic pollutants by changing the surface properties of microbes, interfering with degradative enzymes, and interacting with general metabolism.


Assuntos
Poluentes Ambientais , Mercúrio , Metaloides , Metais Pesados , Poluentes do Solo , Metais Pesados/análise , Biodegradação Ambiental , Poluentes do Solo/análise , Monitoramento Ambiental
10.
Childs Nerv Syst ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38802706

RESUMO

PURPOSE: Genetic mutations stand as pivotal factors leading to the occurrence of embryonal tumor with multilayered rosettes (ETMR). This study aims to identify improved treatment approaches by unraveling the genetic drivers and immune infiltration in ETMR. METHODS: Two siblings with ETMR, treated at the General Hospital of Ningxia Medical University, were enrolled. Diagnosis involved MRI, Hematoxylin and Eosin (HE), and immunohistochemical (IHC) staining. Differentially expressed genes (DEGs) in ETMR were identified using GSE122077 and GSE14296 datasets. GO and KEGG analyses were used to determine ETMR-related pathways. Whole exome sequencing (WES) was utilized to annotate genetic variations in ETMR. Core genes, identified by protein-protein interaction (PPI), formed a diagnostic model evaluated by Logistic Regression. Single-sample Gene Set Enrichment Analysis (ssGSEA) assessed immune infiltration in ETMR, examining correlations between immune cells and core genes. RESULTS: Two siblings were diagnosed with ETMR. In ETMR, 135 DEGs were identified, of which 25 genes were annotated with 28 mutation sites. Moreover, ETMR-related pathways included cell cycle, synaptic functions, and neurodegeneration. Three ETMR-related core genes (ALB, PSMD1, and PAK2) were screened by protein-protein interaction (PPI). The diagnostic model constructed using these genes demonstrated an AUC value of 0.901 (95% CI: 0.811-0.991) in the training set, indicating accurate predictions in ETMR. Enhanced ssGSEA scores for 16 immune cells in ETMR tissues suggested a strong immune response. CONCLUSION: This study identifies diagnostic models associated with three core variant genes (ALB, PSMD1, PAK2) and enhanced immune cell activity in ETMR. It reveals crucial genetic features and significant immune responses in ETMR.

11.
BMC Musculoskelet Disord ; 25(1): 548, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39010016

RESUMO

BACKGROUND: Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors represent an effective strategy for reducing cardiovascular disease risk. Yet, PCSK9's impact on osteoporosis remains unclear. Hence, we employed Mendelian randomization (MR) analysis for examining PCSK9 inhibitor effects on osteoporosis. METHODS: Single nucleotide polymorphisms (SNPs) for 3-hydroxy-3-methylglutaryl cofactor A reductase (HMGCR) and PCSK9 were gathered from available online databases for European pedigrees. Four osteoporosis-related genome-wide association studies (GWAS) data served as the main outcomes, and coronary artery disease (CAD) as a positive control for drug-targeted MR analyses. The results of MR analyses examined by sensitivity analyses were incorporated into a meta-analysis for examining causality between PCSK9 and HMGCR inhibitors and osteoporosis. RESULTS: The meta-analysis involving a total of 1,263,102 subjects, showed that PCSK9 inhibitors can increase osteoporosis risk (P < 0.05, I2, 39%). However, HMGCR inhibitors are not associated with osteoporosis risk. Additionally, a replication of the analysis was conducted with another exposure-related GWAS dataset, which led to similar conclusions. CONCLUSION: PCSK9 inhibitors increase osteoporosis risk. However, HMGCR inhibitors are unremarkably linked to osteoporosis.


Assuntos
Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Osteoporose , Inibidores de PCSK9 , Polimorfismo de Nucleotídeo Único , Humanos , Osteoporose/genética , Osteoporose/induzido quimicamente , Osteoporose/epidemiologia , Pró-Proteína Convertase 9/genética , Pró-Proteína Convertase 9/metabolismo , Hidroximetilglutaril-CoA Redutases/genética
12.
Environ Toxicol ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38717048

RESUMO

BACKGROUND: Gastric cancer (GC) is a prevalent malignant tumor of the gastrointestinal (GI) system. However, the lack of reliable biomarkers has made its diagnosis, prognosis, and treatment challenging. Immunogenic cell death (ICD) is a type of programmed cell death that is strongly related to the immune system. However, its function in GC requires further investigation. METHOD: We used multi-omics and multi-angle approaches to comprehensively explore the prognostic features of ICD in patients with stomach adenocarcinoma (STAD). At the single-cell level, we screened genes associated with ICD at the transcriptome level, selected prognostic genes related to ICD using weighted gene co-expression network analysis (WGCNA) and machine learning, and constructed a prognostic model. In addition, we constructed nomograms that incorporated pertinent clinical features and provided effective tools for prognostic prediction in clinical settings. We also investigated the sensitivity of the risk subgroups to both immunotherapy and drugs. Finally, in addition to quantitative real-time polymerase chain reaction, immunofluorescence was used to validate the expression of ICD-linked genes. RESULTS: Based on single-cell and transcriptome WGCNA analyses, we identified 34 ICD-related genes, of which 11 were related to prognosis. We established a prognostic model using the least absolute shrinkage and selection operator (LASSO) algorithm and identified dissimilarities in overall survival (OS) and progression-free survival (PFS) in risk subgroups. The nomograms associated with the ICD-related signature (ICDRS) demonstrated a good predictive value for clinical applications. Moreover, we detected changes in the tumor microenvironment (TME), including biological functions, mutation landscapes, and immune cell infiltration, between the high- and low-risk groups. CONCLUSION: We constructed an ICD-related prognostic model that incorporated features related to cell death. This model can serve as a useful tool for predicting the prognosis of GC, targeted prevention, and personalized medicine.

13.
Sensors (Basel) ; 24(4)2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38400488

RESUMO

In addressing challenges related to high parameter counts and limited training samples for finger vein recognition, we present the FV-MViT model. It serves as a lightweight deep learning solution, emphasizing high accuracy, portable design, and low latency. The FV-MViT introduces two key components. The Mul-MV2 Block utilizes a dual-path inverted residual connection structure for multi-scale convolutions, extracting additional local features. Simultaneously, the Enhanced MobileViT Block eliminates the large-scale convolution block at the beginning of the original MobileViT Block. It converts the Transformer's self-attention into separable self-attention with linear complexity, optimizing the back end of the original MobileViT Block with depth-wise separable convolutions. This aims to extract global features and effectively reduce parameter counts and feature extraction times. Additionally, we introduce a soft target center cross-entropy loss function to enhance generalization and increase accuracy. Experimental results indicate that the FV-MViT achieves a recognition accuracy of 99.53% and 100.00% on the Shandong University (SDU) and Universiti Teknologi Malaysia (USM) datasets, with equal error rates of 0.47% and 0.02%, respectively. The model has a parameter count of 5.26 million and exhibits a latency of 10.00 milliseconds from the sample input to the recognition output. Comparison with state-of-the-art (SOTA) methods reveals competitive performance for FV-MViT.


Assuntos
Fontes de Energia Elétrica , Extremidades , Humanos , Entropia , Reconhecimento Psicológico , Veias
14.
Syst Parasitol ; 101(3): 33, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647718

RESUMO

The mitochondrial (mt) genome can provide data for phylogenetic analyses and evolutionary biology. Herein, we sequenced and annotated the complete mt genome of Ergasilus anchoratus. This mt genome was 13852 bp long and comprised 13 protein-coding genes (PCGs), 22 tRNAs and 2 rRNAs. All PCGs used the standard ATN start codons and complete TAA/TAG termination codons. A majority of tRNA genes exhibited standard cloverleaf secondary structures, with the exception of one tRNA that lacked the TψC arm (trnC), and three tRNAs that lacked the DHU arm (trnR, trnS1 and trnS2). Phylogenetic analyses conducted using Bayesian inference (BI) and maximum likelihood (ML) methods both supported Ergasilidae as a monophyletic family forming a sister group to Lernaea cyprinacea and Paracyclopina nana. It also supported the monophyly of orders Calanoida, Cyclopoida, and Siphonostomatoida; and the monophyly of families Harpacticidae, Ergasilidae, Diaptomidae, and Calanidae. The gene orders of E. anchoratus and Sinergasilus undulatus were identical, which represents the first instance of two identical gene orders in copepods. More mt genomes are needed to better understand the phylogenetic relationships within Copepoda in the future.


Assuntos
Copépodes , Genoma Mitocondrial , Filogenia , Animais , Genoma Mitocondrial/genética , Copépodes/genética , Copépodes/classificação
15.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(5): 450-455, 2024 May 15.
Artigo em Zh | MEDLINE | ID: mdl-38802903

RESUMO

OBJECTIVES: To investigate the incidence rate, clinical characteristics, and prognosis of neonatal stroke in Shenzhen, China. METHODS: Led by Shenzhen Children's Hospital, the Shenzhen Neonatal Data Collaboration Network organized 21 institutions to collect 36 cases of neonatal stroke from January 2020 to December 2022. The incidence, clinical characteristics, treatment, and prognosis of neonatal stroke in Shenzhen were analyzed. RESULTS: The incidence rate of neonatal stroke in 21 hospitals from 2020 to 2022 was 1/15 137, 1/6 060, and 1/7 704, respectively. Ischemic stroke accounted for 75% (27/36); boys accounted for 64% (23/36). Among the 36 neonates, 31 (86%) had disease onset within 3 days after birth, and 19 (53%) had convulsion as the initial presentation. Cerebral MRI showed that 22 neonates (61%) had left cerebral infarction and 13 (36%) had basal ganglia infarction. Magnetic resonance angiography was performed for 12 neonates, among whom 9 (75%) had involvement of the middle cerebral artery. Electroencephalography was performed for 29 neonates, with sharp waves in 21 neonates (72%) and seizures in 10 neonates (34%). Symptomatic/supportive treatment varied across different hospitals. Neonatal Behavioral Neurological Assessment was performed for 12 neonates (33%, 12/36), with a mean score of (32±4) points. The prognosis of 27 neonates was followed up to around 12 months of age, with 44% (12/27) of the neonates having a good prognosis. CONCLUSIONS: Ischemic stroke is the main type of neonatal stroke, often with convulsions as the initial presentation, involvement of the middle cerebral artery, sharp waves on electroencephalography, and a relatively low neurodevelopment score. Symptomatic/supportive treatment is the main treatment method, and some neonates tend to have a poor prognosis.


Assuntos
Acidente Vascular Cerebral , Humanos , Masculino , Recém-Nascido , Feminino , China/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Prognóstico , Eletroencefalografia , Incidência , Imageamento por Ressonância Magnética
16.
Diabetologia ; 66(3): 535-550, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36331598

RESUMO

AIMS/HYPOTHESIS: Glucagon receptor (GCGR) antagonism ameliorates hyperglycaemia and promotes beta cell regeneration in mouse models of type 2 diabetes. However, the underlying mechanisms remain unclear. The present study aimed to investigate the mechanism of beta cell regeneration induced by GCGR antagonism in mice. METHODS: The db/db mice and high-fat diet (HFD)+streptozotocin (STZ)-induced mice with type 2 diabetes were treated with antagonistic GCGR monoclonal antibody (mAb), and the metabolic variables and islet cell quantification were evaluated. Plasma cytokine array and liver RNA sequencing data were used to screen possible mediators, including fibroblast growth factor 21 (FGF21). ELISA, quantitative RT-PCR and western blot were applied to verify FGF21 change. Blockage of FGF21 signalling by FGF21-neutralising antibody (nAb) was used to clarify whether FGF21 was involved in the effects of GCGR mAb on the expression of beta cell identity-related genes under plasma-conditional culture and hepatocyte co-culture conditions. FGF21 nAb-treated db/db mice, systemic Fgf21-knockout (Fgf21-/-) diabetic mice and hepatocyte-specific Fgf21-knockout (Fgf21Hep-/-) diabetic mice were used to reveal the involvement of FGF21 in beta cell regeneration. A BrdU tracing study was used to analyse beta cell proliferation in diabetic mice treated with GCGR mAb. RESULTS: GCGR mAb treatment improved blood glucose control, and increased islet number (db/db 1.6±0.1 vs 0.8±0.1 per mm2, p<0.001; HFD+STZ 1.2±0.1 vs 0.5±0.1 per mm2, p<0.01) and area (db/db 2.5±0.2 vs 1.2±0.2%, p<0.001; HFD+STZ 1.0±0.1 vs 0.3±0.1%, p<0.01) in diabetic mice. The plasma cytokine array and liver RNA sequencing data showed that FGF21 levels in plasma and liver were upregulated by GCGR antagonism. The GCGR mAb induced upregulation of plasma FGF21 levels (db/db 661.5±40.0 vs 466.2±55.7 pg/ml, p<0.05; HFD+STZ 877.0±106.8 vs 445.5±54.0 pg/ml, p<0.05) and the liver levels of Fgf21 mRNA (db/db 3.2±0.5 vs 1.8±0.1, p<0.05; HFD+STZ 2.0±0.3 vs 1.0±0.2, p<0.05) and protein (db/db 2.0±0.2 vs 1.4±0.1, p<0.05; HFD+STZ 1.6±0.1 vs 1.0±0.1, p<0.01). Exposure to plasma or hepatocytes from the GCGR mAb-treated mice upregulated the mRNA levels of characteristic genes associated with beta cell identity in cultured mouse islets and a beta cell line, and blockage of FGF21 activity by an FGF21 nAb diminished this upregulation. Notably, the effects of increased beta cell number induced by GCGR mAb were attenuated in FGF21 nAb-treated db/db mice, Fgf21-/- diabetic mice and Fgf21Hep-/- diabetic mice. Moreover, GCGR mAb treatment enhanced beta cell proliferation in the two groups of diabetic mice, and this effect was weakened in Fgf21-/- and Fgf21Hep-/- mice. CONCLUSIONS/INTERPRETATION: Our findings demonstrate that liver-derived FGF21 is involved in the GCGR antagonism-induced beta cell regeneration in a mouse model of type 2 diabetes.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Células Secretoras de Glucagon , Camundongos , Animais , Glucagon/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Células Secretoras de Glucagon/metabolismo , Diabetes Mellitus Experimental/metabolismo , Receptores de Glucagon/genética , Modelos Animais de Doenças , Fígado/metabolismo , Citocinas/metabolismo , Camundongos Endogâmicos C57BL
17.
BMC Genomics ; 24(1): 633, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37872493

RESUMO

Nitrate is a primary nitrogen source for plant growth, and previous studies have indicated a correlation between nitrogen and browning. Nitrate transporters (NRTs) are crucial in nitrate allocation. Here, we utilized a genome-wide approach to identify and analyze the expression pattern of 74 potential GbNRTs under nitrate treatments during calluses browning in Ginkgo, including 68 NITRATE TRANSPORTER 1 (NRT1)/PEPTIDE TRANSPORTER (PTR) (NPF), 4 NRT2 and 2 NRT3. Conserved domains, motifs, phylogeny, and cis-acting elements (CREs) were analyzed to demonstrate the evolutionary conservation and functional diversity of GbNRTs. Our analysis showed that the NPF family was divided into eight branches, with the GbNPF2 and GbNPF6 subfamilies split into three groups. Each GbNRT contained 108-214 CREs of 19-36 types, especially with binding sites of auxin and transcription factors v-myb avian myeloblastosis viral oncogene homolog (MYB) and basic helix-loop-helix (bHLH). The E1X1X2E2R motif had significant variations in GbNPFs, indicating changes in the potential dynamic proton transporting ability. The expression profiles of GbNRTs indicated that they may function in regulating nitrate uptake and modulating the signaling of auxin and polyphenols biosynthesis, thereby affecting browning in Ginkgo callus induction. These findings provide a better understanding of the role of NRTs during NO3- uptake and utilization in vitro culture, which is crucial to prevent browning and develop an efficient regeneration and suspension production system in Ginkgo.


Assuntos
Nitratos , Proteínas de Plantas , Nitratos/farmacologia , Nitratos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ginkgo biloba/genética , Proteínas de Transporte de Ânions/genética , Proteínas de Transporte de Ânions/química , Proteínas de Transporte de Ânions/metabolismo , Transportadores de Nitrato , Nitrogênio/metabolismo , Ácidos Indolacéticos , Regulação da Expressão Gênica de Plantas , Filogenia
18.
BMC Cancer ; 23(1): 547, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37322411

RESUMO

BACKGROUND: Immune-checkpoint inhibitors (ICIs) have revolutionized the treatment of hepatocellular carcinoma (HCC). However, long-term survival outcomes and treatment response of HCC patients undergoing immunotherapy is unpredictable. The study aimed to evaluate the role of alpha-fetoprotein (AFP) combined with neutrophil-to-lymphocyte ratio (NLR) to predict the prognosis and treatment response of HCC patients receiving ICIs. METHODS: Patients with unresectable HCC who received ICI treatment were included. The HCC immunotherapy score was developed from a retrospective cohort at the Eastern Hepatobiliary Surgery Hospital to form the training cohort. The clinical variables independently associated with overall survival (OS) were identified using univariate and multivariate Cox regression analysis. Based on multivariate analysis of OS, a predictive score based on AFP and NLR was constructed, and patients were stratified into three risk groups according to this score. The clinical utility of this score to predict progression-free survival (PFS) and differentiate objective response rate (ORR) and disease control rate (DCR) was also performed. This score was validated in an independent external validation cohort at the First Affiliated Hospital of Wenzhou Medical University. RESULTS: Baseline AFP ≤ 400 ng/ml (hazard ratio [HR] 0.48; 95% CI, 0.24-0.97; P = 0.039) and NLR ≤ 2.77 (HR 0.11; 95% CI, 0.03-0.37; P<0.001) were found to be independent risk factors of OS. The two labolatory values were used to develop the score to predict survival outcomes and treatment response in HCC patients receiving immunotherapy, which assigned 1 point for AFP > 400 ng/ml and 3 points for NLR > 2.77. Patients with 0 point were classified as the low-risk group. Patients with 1-3 points were categorized as the intermediate-risk group. Patients with 4 points were classified as the high-risk group. In the training cohort, the median OS of the low-risk group was not reached. The median OS of the intermediate-risk group and high-risk group were 29.0 (95% CI 20.8-37.3) months and 16.0 (95% CI 10.8-21.2) months, respectively (P < 0.001). The median PFS of the low-risk group was not reached. The median PFS of the intermediate-risk group and high-risk group were 14.6 (95% CI 11.3-17.8) months and 7.6 (95% CI 3.6-11.7) months, respectively (P < 0.001). The ORR and DCR were highest in the low-risk group, followed by the intermediate-risk group and the high-risk group (P < 0.001, P = 0.007, respectively). This score also had good predictive power using the validation cohort. CONCLUSION: The HCC immunotherapy score based on AFP and NLR can predict survival outcomes and treatment response in patients receiving ICI treatments, suggesting that this score could serve as a useful tool for identification of HCC patients likely to benefit from immunotherapy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , alfa-Fetoproteínas , Inibidores de Checkpoint Imunológico/uso terapêutico , Neutrófilos/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Estudos Retrospectivos , Linfócitos/patologia
19.
BMC Cancer ; 23(1): 1017, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37867191

RESUMO

BACKGROUND: The use of Anti-PD-1 therapy has yielded promising outcomes in hepatocellular carcinoma (HCC). However, limited research has been conducted on the overall survival (OS) of patients with varying tumor responses and treatment duration. METHODS: This retrospective study analyzed HCC patients who received sintilimab between January 2019 and December 2020 at four centers in China. The evaluation of tumor progression was based on Response Evaluation Criteria in Solid Tumors version 1.1. The study investigated the correlation between tumor response and OS, and the impact of drug use on OS following progressive disease (PD). RESULTS: Out of 441 treated patients, 159 patients satisfied the inclusion criteria. Among them, 77 patients with disease control exhibited a significantly longer OS compared to the 82 patients with PD (median OS 26.0 vs. 11.3 months, P < 0.001). Additionally, the OS of patients with objective response (OR) was better than that of patients with stable disease (P = 0.002). Among the 47 patients with PD who continued taking sintilimab, the OS was better than the 35 patients who discontinued treatment (median OS 11.4 vs. 6.9 months, P = 0.042). CONCLUSIONS: In conclusion, the tumor response in HCC patients who received sintilimab affects OS, and patients with PD may benefit from continued use of sintilimab.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Estudos Retrospectivos , Critérios de Avaliação de Resposta em Tumores Sólidos
20.
Nature ; 548(7665): 112-116, 2017 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-28723898

RESUMO

The major energy source for most cells is glucose, from which ATP is generated via glycolysis and/or oxidative metabolism. Glucose deprivation activates AMP-activated protein kinase (AMPK), but it is unclear whether this activation occurs solely via changes in AMP or ADP, the classical activators of AMPK. Here, we describe an AMP/ADP-independent mechanism that triggers AMPK activation by sensing the absence of fructose-1,6-bisphosphate (FBP), with AMPK being progressively activated as extracellular glucose and intracellular FBP decrease. When unoccupied by FBP, aldolases promote the formation of a lysosomal complex containing at least v-ATPase, ragulator, axin, liver kinase B1 (LKB1) and AMPK, which has previously been shown to be required for AMPK activation. Knockdown of aldolases activates AMPK even in cells with abundant glucose, whereas the catalysis-defective D34S aldolase mutant, which still binds FBP, blocks AMPK activation. Cell-free reconstitution assays show that addition of FBP disrupts the association of axin and LKB1 with v-ATPase and ragulator. Importantly, in some cell types AMP/ATP and ADP/ATP ratios remain unchanged during acute glucose starvation, and intact AMP-binding sites on AMPK are not required for AMPK activation. These results establish that aldolase, as well as being a glycolytic enzyme, is a sensor of glucose availability that regulates AMPK.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Frutose-Bifosfato Aldolase/metabolismo , Frutosedifosfatos/metabolismo , Glucose/metabolismo , Quinases Proteína-Quinases Ativadas por AMP , Difosfato de Adenosina/metabolismo , Monofosfato de Adenosina/metabolismo , Adenosina Trifosfatases/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Proteína Axina/metabolismo , Sítios de Ligação , Ativação Enzimática , Fibroblastos , Frutose-Bifosfato Aldolase/genética , Glucose/deficiência , Humanos , Masculino , Camundongos , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo
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