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1.
JACC Basic Transl Sci ; 9(8): 982-1001, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39297139

RESUMO

Phosphorylation of myofilament proteins critically regulates beat-to-beat cardiac contraction and is typically altered in heart failure (HF). ß-Adrenergic activation induces phosphorylation in numerous substrates at the myofilament. Nevertheless, how cardiac ß-adrenoceptors (ßARs) signal to the myofilament in healthy and diseased hearts remains poorly understood. The aim of this study was to uncover the spatiotemporal regulation of local ßAR signaling at the myofilament and thus identify a potential therapeutic target for HF. Phosphoproteomic analysis of substrate phosphorylation induced by different ßAR ligands in mouse hearts was performed. Genetically encoded biosensors were used to characterize cyclic adenosine and guanosine monophosphate signaling and the impacts on excitation-contraction coupling induced by ß1AR ligands at both the cardiomyocyte and whole-heart levels. Myofilament signaling circuitry was identified, including protein kinase G1 (PKG1)-dependent phosphorylation of myosin light chain kinase, myosin phosphatase target subunit 1, and myosin light chain at the myofilaments. The increased phosphorylation of myosin light chain enhances cardiac contractility, with a minimal increase in calcium (Ca2+) cycling. This myofilament signaling paradigm is promoted by carvedilol-induced ß1AR-nitric oxide synthetase 3 (NOS3)-dependent cyclic guanosine monophosphate signaling, drawing a parallel to the ß1AR-cyclic adenosine monophosphate-protein kinase A pathway. In patients with HF and a mouse HF model of myocardial infarction, increasing expression and association of NOS3 with ß1AR were observed. Stimulating ß1AR-NOS3-PKG1 signaling increased cardiac contraction in the mouse HF model. This research has characterized myofilament ß1AR-PKG1-dependent signaling circuitry to increase phosphorylation of myosin light chain and enhance cardiac contractility, with a minimal increase in Ca2+ cycling. The present findings raise the possibility of targeting this myofilament signaling circuitry for treatment of patients with HF.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 323: 124929, 2024 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-39116592

RESUMO

The competition among drugs for binding to plasma proteins is regarded as a pharmacokinetic drug interaction. Competition between antitumor agents and other drugs for plasma protein binding can alter the free concentration of the drug, potentially impacting its efficacy and increasing the risk of toxic side effects. Through a range of spectroscopic techniques, this study examined the interaction between limonin and human serum albumin (HSA) in the context of berberine (Ber) and curcumin (Cur) under physiological conditions to clarify the binding mechanisms of binary and ternary systems at the molecular level. As demonstrated by fluorescence quenching experiments, Static quenching was identified as the mechanism of interaction between HSA and limonin. The results of site competition experiments indicated that the binding site between limonin and HSA was site I, a result further supported by molecular docking simulations. Through the use of thermodynamic data calculations, it was determined that limonin forms a stable complex with HSA by establishing hydrogen bonds and van der Waals forces. Circular dichroism (CD) spectroscopy, three-dimensional (3D) fluorescence spectroscopy, and synchronous fluorescence spectroscopy (SFS) employed to validate the notion that limonin perturbed the microenvironment of amino acids and induced conformational changes in HSA. What's more, the presence of Ber or Cur was found to have further modified the alterations observed in the interaction between the original HSA-limonin binary system. In vitro cellular experiments showed that interaction with HSA reduced the antitumor activity of limonin. In contrast, adding Ber or Cur increased the inhibition rate of tumor cells. The coexistence of both Ber and Cur significantly diminished limonin's binding affinity to HSA. The current investigation enhances comprehension regarding the binding characteristics and interaction mechanisms involving limonin, Ber, Cur, and HSA. It explores the potential of HSA as a versatile drug carrier and furnishes theoretical underpinnings for co-administrative strategies.


Assuntos
Antineoplásicos , Berberina , Curcumina , Limoninas , Simulação de Acoplamento Molecular , Ligação Proteica , Albumina Sérica Humana , Espectrometria de Fluorescência , Humanos , Berberina/farmacologia , Berberina/química , Berberina/metabolismo , Curcumina/farmacologia , Curcumina/metabolismo , Curcumina/química , Limoninas/farmacologia , Limoninas/química , Limoninas/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/metabolismo , Albumina Sérica Humana/metabolismo , Albumina Sérica Humana/química , Sítios de Ligação , Termodinâmica , Linhagem Celular Tumoral , Dicroísmo Circular
3.
BMC Public Health ; 24(1): 2301, 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39180018

RESUMO

PURPOSE: The objective of this study is to assess the impact of smoking on stroke prevalence and to delineate the relationship between smoking-related factors and the risk of stroke, incorporating an analysis of demographic variations influencing this association. METHODS: Our analysis encompassed 9,176 participants, evaluating clinical attributes alongside smoking-related characteristics such as duration of cigarette consumption, and levels of nicotine, tar, and carbon monoxide. We employed weighted univariate logistic regression and restricted cubic splines to examine the association between smoking indicators and stroke risk, complemented by subgroup analyses for demographic differentiation. RESULTS: The overall prevalence of stroke in our cohort was 3.4%. Statistically significant associations were found between stroke incidence and factors such as age, gender, education, and marital status (p < 0.05). Adjusted logistic regression models showed increased odds ratios (ORs) for stroke with higher nicotine and carbon monoxide levels across progressively adjusted models: Model 1 (unadjusted), Model 2 (adjusted for age, gender), Model 3 (further adjusted for education, marital status, BMI, PIR), and Model 4 (fully adjusted for additional factors including hypertension, hyperlipidemia, diabetes, and drinking). Specifically, ORs for nicotine increased from 2.39 in Model 1 to 2.64 in Model 4; for carbon monoxide, from 1.10 to 1.11 over the same models.​The threshold analysis using restricted cubic splines revealed critical points for stroke risk increase at smoke exposure levels of 410 units, tar 12 mg, nicotine 1.1 mg, and carbon monoxide 12 ppm. Above these thresholds, stroke risk escalates significantly. Additionally, the presence of family smoking history was associated with higher stroke risks compared to those without such history. CONCLUSION: This study confirms that smoking significantly contributes to increased stroke risk, particularly through exposure to nicotine and carbon monoxide. The findings emphasize the necessity for tailored stroke prevention strategies that specifically address smoking behaviors and consider demographic susceptibilities. Incorporating smoking-related indicators into risk assessment models could enhance the precision of stroke prevention efforts.


Assuntos
Fumar , Acidente Vascular Cerebral , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Prevalência , Idoso , Fumar/epidemiologia , Fumar/efeitos adversos , Fatores de Risco , Adulto , Monóxido de Carbono/análise , Nicotina/efeitos adversos
4.
J Environ Manage ; 366: 121792, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39002459

RESUMO

Signal transduction is an important mode of algae-bacteria interaction, in which bacterial quorum sensing (QS) may affect microalgal growth and metabolism. Currently, little is known whether acyl homoserine lactones (AHLs) released by bacteria can affect the pollutant removal by algae-bacteria consortia (ABC). In this study, we constructed ABC using Chlorella vulgaris (Cv) with two AHLs-producing bacteria and investigated their performance in the removal of multiple pollutants, including chemical oxygen demand (COD), total nitrogen (TN), phosphorus (P), and cadmium (Cd). The AHLs-producing bacteria, namely Agrobacterium sp. (Ap) and Ensifer adherens (Ea), were capable of forming a symbiosis with C. vulgaris. Consortia of Cv and Ap with ratio of 2:1 (Cv2-Ap1) showed the optimal growth promotion and higher removal of Cd, COD, TN, and P compared to the C. vulgaris monoculture. Cv2-Ap1 ABC removed 36.1-47.5% of Cd, 94.5%-94.6% COD, 37.1%-56.0% TN, and 90.4%-93.5% P from the culture medium. In addition, increase of intracellular neutral lipids and extracellular protein, as well as the types of functional groups on cell surface contributed to Cd removal and tolerance in the Cv2-Ap1 ABC. Six AHLs were detected in the Cv2-Ap1 culture. Among these, 3OC8-HSL and 3OC12-HSL additions promoted the ABC growth and enhanced their Cd accumulation. These findings may contribute to further understanding of AHL-mediated communication between algae and bacteria and provide support bioremediation efforts of metal-containing wastewater.


Assuntos
Acil-Butirolactonas , Cádmio , Cádmio/metabolismo , Acil-Butirolactonas/metabolismo , Chlorella vulgaris/metabolismo , Chlorella vulgaris/crescimento & desenvolvimento , Bactérias/metabolismo , Biodegradação Ambiental , Percepção de Quorum , Fósforo/metabolismo , Nitrogênio/metabolismo
5.
Tissue Eng Regen Med ; 21(6): 855-865, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38652220

RESUMO

BACKGROUND: Carbonic anhydrase 1 (CA1) has been found to be involved in osteogenesis and osteoclast in various human diseases, but the molecular mechanisms are not completely understood. In this study, we aim to use siRNA and lentivirus to reduce or increase the expression of CA1 in Dental follicle stem cells (DFSCs), in order to further elucidate the role and mechanism of CA1 in osteogenesis, and provide better osteogenic growth factors and stem cell selection for the application of bone tissue engineering in alveolar bone fracture transplantation. METHODS: The study used RNA interference and lentiviral vectors to manipulate the expression of the CA1 gene in DFSCs during in vitro osteogenic induction. The expression of osteogenic marker genes was evaluated and changes in CA1, alkaline phosphatase (ALP), Runt-related transcription factor 2 (RUNX2), and Bone morphogenetic proteins (BMP2) were measured using quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting (WB). The osteogenic effect was assessed through Alizarin Red staining. RESULTS: The mRNA and protein expression levels of CA1, ALP, RUNX2, and BMP2 decreased distinctly in the si-CA1 group than other groups (p < 0.05). In the Lentivirus-CA1 (LV-CA1) group, the mRNA and protein expressions of CA1, ALP, RUNX2, and BMP2 were amplified to varying degrees than other groups (p < 0.05). Apart from CA1, BMP2 (43.01%) and ALP (36.69%) showed significant upregulation (p < 0.05). Alizarin red staining indicated that the LV-CA1 group produced more calcified nodules than other groups, with a higher optical density (p < 0.05), and the osteogenic effect was superior. CONCLUSIONS: CA1 can impact osteogenic differentiation via BMP related signaling pathways, positioning itself upstream in osteogenic signaling pathways, and closely linked to osteoblast calcification and ossification processes.


Assuntos
Diferenciação Celular , Saco Dentário , Osteogênese , Transdução de Sinais , Células-Tronco , Saco Dentário/citologia , Saco Dentário/metabolismo , Humanos , Células-Tronco/metabolismo , Células-Tronco/citologia , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Proteína Morfogenética Óssea 2/metabolismo , Proteína Morfogenética Óssea 2/genética , Células Cultivadas , Fosfatase Alcalina/metabolismo
6.
Int Immunopharmacol ; 132: 111947, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38552296

RESUMO

BACKGROUND: Programmed cell death protein-1 (PD-1) inhibitors have shown promising clinical efficacy in treating advanced hepatocellular carcinoma (HCC). However, little evidence exists regarding their treatment patterns and outcomes in real-world practice in China. This study aimed to investigate real-world treatment patterns and outcomes of PD-1 inhibitors as first-line therapies for patients with advanced HCC in China. METHODS: The study population included adult patients with advanced HCC who were initially treated with PD-1 inhibitors from April 2020 to November 2022 in China. Descriptive statistics were used to report first-line treatment patterns and associations between patient characteristics and the most frequently used treatment patterns. The effectiveness of first-line treatment with PD-1 inhibitors was also evaluated according to survival and tumor response. RESULTS: The analyses enrolled 480 patients. The four most frequently used first-line treatment patterns of camrelizumab, tislelizumab, camrelizumab + TACE, and tislelizumab + TACE showed statistical differences in patient characteristics of gender, HBV infection, liver cirrhosis, BCLC stage, and portal vein tumor thrombus (all P < 0.05). However, there was no significant difference in median progression-free survival among the first-line treatments of tislelizumab, camrelizumab, and tislelizumab + TACE (not reached vs. 4.4 months vs. 3.6 months, P = 0.5178). The three groups had similar objective response rates (25.0 % vs. 28.6 % vs. 28.6 %, P = 0.927), and disease control rates (73.1 % vs. 78.6 % vs. 64.3 %, P = 0.573) with no statistical significance. CONCLUSIONS: Our findings provided insights into potential therapeutic strategies of PD-1 inhibitors in first-line settings for advanced HCC in real-world practice in China. It was recommended to consider patient characteristics associated with therapeutic options when making clinical decisions. Prospective randomized controlled studies with larger sample sizes and longer follow-up times were warranted further to verify the potential clinical benefits of PD-1 inhibitors.


Assuntos
Anticorpos Monoclonais Humanizados , Carcinoma Hepatocelular , Inibidores de Checkpoint Imunológico , Neoplasias Hepáticas , Receptor de Morte Celular Programada 1 , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/mortalidade , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/mortalidade , Masculino , Feminino , Pessoa de Meia-Idade , Inibidores de Checkpoint Imunológico/uso terapêutico , Idoso , Anticorpos Monoclonais Humanizados/uso terapêutico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , China , Resultado do Tratamento , Adulto , Quimioembolização Terapêutica , Estudos Retrospectivos
7.
J Stroke Cerebrovasc Dis ; 33(5): 107666, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38423152

RESUMO

OBJECTIVE: Velvet antler polypeptide (VAP) has been shown to play important roles in the immune and nervous systems. The purpose of this study was to investigate the protective effects of VAP on cerebral ischemic injury with the involvement of NF-κB signaling pathway in vitro. MATERIALS AND METHODS: PC-12 cells stimulated by oxygen-glucose deprivation/reperfusion (OGD/R) was used to mimic cerebral ischemic injury in vitro. The levels of ROS, SOD, and intracellular concentrations of Ca2+ were measured by the relevant kits. Meanwhile, the expressions of inflammatory cytokines (IL-6, IL-1ß, and TNF-α) were determined by ELISA kit assay. In addition, MTT, EdU, and flow cytometry assays were used to measure the cell proliferation and apoptosis. Besides which, the related proteins of NF-κB signaling pathway were measured by western blotting assay. RESULTS: VAP alleviated cerebral ischemic injury by reducing OGD/R-induced oxidative stress, inflammation, and apoptosis in PC-12 cells in a time dependent manner. Mechanistically, VAP inhibited the levels of p-p65 and p-IkB-α in a time dependent manner, which was induced by OGD/R operation. Moreover, NF-κB agonist diprovocim overturned the suppression effects of VAP on OGD/R-induced oxidative stress, inflammation, and apoptosis in PC-12 cells. CONCLUSIONS: The results demonstrate that VAP may alleviate cerebral ischemic injury by suppressing the activation of NF-κB signaling pathway.


Assuntos
Chifres de Veado , Traumatismo por Reperfusão , Humanos , Animais , NF-kappa B/metabolismo , Chifres de Veado/metabolismo , Transdução de Sinais , Oxigênio/metabolismo , Citocinas/metabolismo , Inflamação/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Traumatismo por Reperfusão/metabolismo , Apoptose , Glucose
8.
J Neurooncol ; 167(2): 305-313, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38424338

RESUMO

PURPOSE: Currently, there remains a scarcity of established preoperative tests to accurately predict the isocitrate dehydrogenase (IDH) mutation status in clinical scenarios, with limited research has explored the potential synergistic diagnostic performance among metabolite, perfusion, and diffusion parameters. To address this issue, we aimed to develop an imaging protocol that integrated 2-hydroxyglutarate (2HG) magnetic resonance spectroscopy (MRS) and intravoxel incoherent motion (IVIM) by comprehensively assessing metabolic, cellular, and angiogenic changes caused by IDH mutations, and explored the diagnostic efficiency of this imaging protocol for predicting IDH mutation status in clinical scenarios. METHODS: Patients who met the inclusion criteria were categorized into two groups: IDH-wild type (IDH-WT) group and IDH-mutant (IDH-MT) group. Subsequently, we quantified the 2HG concentration, the relative apparent diffusion coefficient (rADC), the relative true diffusion coefficient value (rD), the relative pseudo-diffusion coefficient (rD*) and the relative perfusion fraction value (rf). Intergroup differences were estimated using t-test and Mann-Whitney U test. Finally, we performed receiver operating characteristic (ROC) curve and DeLong's test to evaluate and compare the diagnostic performance of individual parameters and their combinations. RESULTS: 64 patients (female, 21; male, 43; age, 47.0 ± 13.7 years) were enrolled. Compared with IDH-WT gliomas, IDH-MT gliomas had higher 2HG concentration, rADC and rD (P < 0.001), and lower rD* (P = 0.013). The ROC curve demonstrated that 2HG + rD + rD* exhibited the highest areas under curve (AUC) value (0.967, 95%CI 0.889-0.996) for discriminating IDH mutation status. Compared with each individual parameter, the predictive efficiency of 2HG + rADC + rD* and 2HG + rD + rD* shows a statistically significant enhancement (DeLong's test: P < 0.05). CONCLUSIONS: The integration of 2HG MRS and IVIM significantly improves the diagnostic efficiency for predicting IDH mutation status in clinical scenarios.


Assuntos
Neoplasias Encefálicas , Glioma , Glutaratos , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Estudos Retrospectivos , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Glioma/diagnóstico , Glioma/genética , Glioma/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Mutação
9.
Cell Mol Neurobiol ; 44(1): 24, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38372822

RESUMO

Neuroinflammation is an important pathogenesis of neurological diseases and causes a series of physiopathological changes, such as abnormal activation of glial cells, neuronal degeneration and death, and disruption of the blood‒brain barrier. Therefore, modulating inflammation may be an important therapeutic tool for treating neurological diseases. Mesenchymal stem cells (MSCs), as pluripotent stem cells, have great therapeutic potential for neurological diseases due to their regenerative ability, immunity, and ability to regulate inflammation. However, recent studies have shown that MSC-derived exosomes (MSC-Exos) play a major role in this process and play a key role in neuroprotection by regulating neuroglia. This review summarizes the recent progress made in regulating neuroinflammation by focusing on the mechanisms by which MSC-Exos are involved in the regulation of glial cells through signaling pathways such as the TLR, NF-κB, MAPK, STAT, and NLRP3 pathways to provide some references for subsequent research and therapy.


Assuntos
Exossomos , Células-Tronco Mesenquimais , Humanos , Doenças Neuroinflamatórias , Inflamação , Barreira Hematoencefálica
10.
J Am Chem Soc ; 145(51): 28030-28037, 2023 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-38091482

RESUMO

The gastric inhibitory polypeptide receptor (GIPR), a G protein-coupled receptor (GPCR) that regulates glucose metabolism and insulin secretion, is a target for the development of therapeutic agents to address type 2 diabetes and obesity. Signal transduction processes mediated by GPCR activation typically result in receptor phosphorylation, but very little is known about GIPR phosphorylation. Mass spectrometry (MS) is a powerful tool for detecting phosphorylation and other post-translational modifications of proteins and for identifying modification sites. However, applying MS methods to GPCRs is challenging because the native expression levels are low and the hydrophobicity of these proteins complicates isolation and enrichment. Here we use a widely available technique, trapped-ion-mobility spectrometry coupled to time-of-flight mass spectrometry (TIMS-TOF MS), to characterize the phosphorylation status of the GIPR. We identified eight serine residues that are phosphorylated, one in an intracellular loop and the remainder in the C-terminal domain. Stimulation with the native agonist GIP enhanced phosphorylation at four of these sites. For comparison, we evaluated tirzepatide (TZP), a dual agonist of the glucagon-like peptide-1 (GLP-1) receptor and the GIPR that has recently been approved for the treatment of type 2 diabetes. Stimulation with TZP enhanced phosphorylation at the same four sites that were enhanced with GIP; however, TZP also enhanced phosphorylation at a fifth site that is unique to this synthetic agonist. This work establishes an important and accessible tool for the characterization of signal transduction via the GIPR and reveals an unanticipated functional difference between GIP and TZP.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Fosforilação , Polipeptídeo Inibidor Gástrico/uso terapêutico , Receptores Acoplados a Proteínas G/metabolismo , Análise Espectral , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo
11.
Hum Vaccin Immunother ; 19(3): 2293299, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38100550

RESUMO

Cancer-testis antigen CT23 is a class of tumor-associated antigens (TAA) characterized by restricted expression in male germ cells and a variety of tumor tissues. Numerous studies have shown that CT23 is closely related to tumor cell viability, proliferation, metastasis and invasion. CT23 is immunogenic and can cause specific immune response in tumor patients. Therefore, it is considered to be one of the best target antigens for designing therapeutic tumor vaccines and T-cell-mediated tumor immunotherapy. In this study, we initially obtained seven HLA-A*0201-restricted CT23 epitope candidate peptides through the T cell epitope prediction program. Subsequently, a T2 cell binding assay revealed the potential binding of all candidate peptides with HLA-A2 molecules. Notably, peptide P7 (ALLVLCYSI) exhibited the highest affinity, as evidenced by a fluorescence index (FI) of 2.19. Dendritic cells (DCs) loaded with CT23 candidate peptide can stimulate CD8+T cell activation and proliferation, and compared with other candidate peptides, candidate peptide P7 is superior. The cytotoxic T lymphocytes (CTLs) stimulated by the peptide P7 had killing effect on tumor cells (HLA-A*0201+, CT23+), but no killing effect on tumor cells (HLA-A*0201-, CT23+). The CTLs induced by the peptide P7 also had a specific killing effect on T2 cells bearing the peptide P7. In summary, our findings suggest that the CT23 peptide P7 (ALLVLCYSI) can induce immune responses and holds potential for tumor-specific CTL therapy.


Assuntos
Neoplasias , Testículo , Humanos , Masculino , Linhagem Celular Tumoral , Antígeno HLA-A2 , Peptídeos , Linfócitos T Citotóxicos , Antígenos de Neoplasias , Epitopos de Linfócito T , Neoplasias/terapia , Neoplasias/metabolismo
12.
J Proteome Res ; 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37991985

RESUMO

Sarcopenia is a progressive disorder characterized by age-related loss of skeletal muscle mass and function. Although significant progress has been made over the years to identify the molecular determinants of sarcopenia, the precise mechanisms underlying the age-related loss of contractile function remains unclear. Advances in "omics" technologies, including mass spectrometry-based proteomic and metabolomic analyses, offer great opportunities to better understand sarcopenia. Herein, we performed mass spectrometry-based analyses of the vastus lateralis from young, middle-aged, and older rhesus monkeys to identify molecular signatures of sarcopenia. In our proteomic analysis, we identified proteins that change with age, including those involved in adenosine triphosphate and adenosine monophosphate metabolism as well as fatty acid beta oxidation. In our untargeted metabolomic analysis, we identified metabolites that changed with age largely related to energy metabolism including fatty acid beta oxidation. Pathway analysis of age-responsive proteins and metabolites revealed changes in muscle structure and contraction as well as lipid, carbohydrate, and purine metabolism. Together, this study discovers new metabolic signatures and offers new insights into the molecular mechanisms underlying sarcopenia for the evaluation and monitoring of a therapeutic treatment of sarcopenia.

13.
Bioconjug Chem ; 34(10): 1802-1810, 2023 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-37751398

RESUMO

Bioconjugates of antibodies and their derivatives radiolabeled with ß+-emitting radionuclides can be utilized for diagnostic PET imaging. Site-specific attachment of radioactive cargo to antibody delivery vectors provides homogeneous, well-defined immunoconjugates. Recent studies have demonstrated the utility of oxaziridine chemistry for site-specific labeling of methionine residues. Herein, we applied this approach to site-specifically radiolabel trastuzumab-derived Fab immunoconjugates with 68Ga, which can be used for in vivo PET imaging of HER2-positive breast cancer tumors. Initially, a reactive azide was introduced to a single solvent-accessible methionine residue in both the wild-type Fab and an engineered derivative containing methionine residue M74, utilizing the principles of oxaziridine chemistry. Subsequently, these conjugates were functionalized with a modified DFO chelator incorporating dibenzocyclooctyne. The resulting DFO-WT and DFO-M74 conjugates were radiolabeled with generator-produced [68Ga]Ga3+, to yield the novel PET radiotracers, [68Ga]Ga-DFO-WT and [68Ga]Ga-DFO-M74. In vitro and in vivo studies demonstrated that [68Ga]Ga-DFO-M74 exhibited a higher affinity for HER2 receptors. Biodistribution studies in mice bearing orthotopic HER2-positive breast tumors revealed a higher uptake of [68Ga]Ga-DFO-M74 in the tumor tissue, accompanied by rapid renal clearance, enabling clear delineation of tumors using PET imaging. Conversely, [68Ga]Ga-DFO-WT exhibited lower uptake and inferior image contrast compared to [68Ga]Ga-DFO-M74. Overall, the results demonstrate that the highly facile methionine-oxaziridine modification approach can be simply applied to the synthesis of stable and site-specifically modified radiolabeled antibody-chelator conjugates with favorable pharmacokinetics for PET imaging.


Assuntos
Imunoconjugados , Neoplasias , Animais , Camundongos , Trastuzumab/química , Radioisótopos de Gálio , Metionina , Distribuição Tecidual , Desferroxamina/química , Tomografia por Emissão de Pósitrons/métodos , Quelantes/química , Racemetionina , Imunoconjugados/química , Zircônio/química , Linhagem Celular Tumoral
14.
Biochemistry ; 62(19): 2878-2892, 2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37699554

RESUMO

Bacteria can use chemical signals to assess their local population density in a process called quorum sensing (QS). Many of these bacteria are common pathogens, including Gram-positive bacteria that utilize agr QS systems regulated by macrocyclic autoinducing peptide (AIP) signals. Listeria monocytogenes, an important foodborne pathogen, uses an agr system to regulate a variety of virulence factors and biofilm formation, yet little is known about the specific roles of agr in Listeria infection and its persistence in various environments. Herein, we report synthetic peptide tools that will enable the study of QS in Listeria. We identified a 6-mer AIP signal in L. monocytogenes supernatants and selected it as a scaffold around which a collection of non-native AIP mimics was designed and synthesized. These peptides were evaluated in cell-based agr reporter assays to generate structure-activity relationships for AIP-based agonism and antagonism in L. monocytogenes. We discovered synthetic agonists with increased potency relative to native AIP and a synthetic antagonist capable of reducing agr activity to basal levels. Notably, the latter peptide was able to reduce biofilm formation by over 90%, a first for a synthetic QS modulator in wild-type L. monocytogenes. The lead agr agonist and antagonist in L. monocytogenes were also capable of antagonizing agr signaling in the related pathogen Staphylococcus aureus, further extending their utility and suggesting different mechanisms of agr activation in these two pathogens. This study represents an important first step in the application of chemical methods to modulate QS and concomitant virulence outcomes in L. monocytogenes.


Assuntos
Listeria monocytogenes , Percepção de Quorum , Peptídeos/farmacologia , Peptídeos/química , Staphylococcus aureus/química , Biofilmes , Proteínas de Bactérias/química
15.
bioRxiv ; 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37577600

RESUMO

Sarcopenia is a progressive disorder characterized by age-related loss of skeletal muscle mass and function. Although significant progress has been made over the years to identify the molecular determinants of sarcopenia, the precise mechanisms underlying the age-related loss of contractile function remains unclear. Advances in omics technologies, including mass spectrometry-based proteomic and metabolomic analyses, offer great opportunities to better understand sarcopenia. Herein, we performed mass spectrometry-based analyses of the vastus lateralis from young, middle-aged, and older rhesus monkeys to identify molecular signatures of sarcopenia. In our proteomic analysis, we identified numerous proteins that change with age, including those involved in adenosine triphosphate and adenosine monophosphate metabolism as well as fatty acid beta oxidation. In our untargeted metabolomic analysis, we identified multiple metabolites that changed with age largely related to energy metabolism including fatty acid beta oxidation. Pathway analysis of age-responsive proteins and metabolites revealed changes in muscle structure and contraction as well as lipid, carbohydrate, and purine metabolism. Together, this study discovers new metabolic signatures and offer new insights into the molecular mechanism underlying sarcopenia for the evaluation and monitoring of therapeutic treatment of sarcopenia.

16.
Front Immunol ; 14: 1212770, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37435059

RESUMO

Introduction: Bromodomain-containing Protein 4 (BRD4) is a transcriptional regulator which coordinates gene expression programs controlling cancer biology, inflammation, and fibrosis. In the context of airway viral infection, BRD4-specific inhibitors (BRD4i) block the release of pro-inflammatory cytokines and prevent downstream epithelial plasticity. Although the chromatin modifying functions of BRD4 in inducible gene expression have been extensively investigated, its roles in post-transcriptional regulation are not well understood. Given BRD4's interaction with the transcriptional elongation complex and spliceosome, we hypothesize that BRD4 is a functional regulator of mRNA processing. Methods: To address this question, we combine data-independent analysis - parallel accumulation-serial fragmentation (diaPASEF) with RNA-sequencing to achieve deep and integrated coverage of the proteomic and transcriptomic landscapes of human small airway epithelial cells exposed to viral challenge and treated with BRD4i. Results: We discover that BRD4 regulates alternative splicing of key genes, including Interferon-related Developmental Regulator 1 (IFRD1) and X-Box Binding Protein 1 (XBP1), related to the innate immune response and the unfolded protein response (UPR). We identify requirement of BRD4 for expression of serine-arginine splicing factors, splicosome components and the Inositol-Requiring Enzyme 1 IREα affecting immediate early innate response and the UPR. Discussion: These findings extend the transcriptional elongation-facilitating actions of BRD4 in control of post-transcriptional RNA processing via modulating splicing factor expression in virus-induced innate signaling.


Assuntos
Processamento Alternativo , Proteínas Nucleares , Humanos , Proteínas Nucleares/genética , Proteômica , Fatores de Transcrição/genética , Inflamação/genética , Proteínas de Ciclo Celular/genética
17.
Mol Cytogenet ; 16(1): 11, 2023 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-37303060

RESUMO

BACKGROUND: Copy-number variants (CNVs) drive many neurodevelopmental-related disorders. Although many neurodevelopmental-related CNVs can give rise to widespread phenotypes, it is necessary to identify the major genes contributing to phenotypic presentation. Copy-number variations in chromosome 6, such as independent 6p deletion and 6p duplication, have been reported in several live-born infants and present widespread abnormalities such as intellectual disability, growth deficiency, developmental delay, and multiple dysmorphic facial features. However, a contiguous deletion and duplication in chromosome 6p regions have been reported in only a few cases. CASE PRESENTATION: In this study, we reported the first duplication of chromosome band 6p25.3-p22.3 with deletion of 6p25.3 in a pedigree. This is the first case reported involving CNVs in these chromosomal regions. In this pedigree, we reported a 1-year-old boy with maternal 6p25-pter duplication characterized by chromosome karyotype. Further analysis using CNV-seq revealed a 20.88-Mb duplication at 6p25.3-p22.3 associated with a contiguous 0.66-Mb 6p25.3 deletion. Whole exome sequencing confirmed the deletion/duplication and identified no pathogenic or likely pathogenic variants related with the patient´s phenotype. The proband presented abnormal growth, developmental delay, skeletal dysplasia, hearing loss, and dysmorphic facial features. Additionally, he presented recurrent infection after birth. CNV-seq using the proband´s parental samples showed that the deletion/duplication was inherited from the proband´s mother, who exhibited a similar phenotype to the proband. When compared with other cases, this proband and his mother presented a new clinical finding: forearm bone dysplasia. The major candidate genes contributing to recurrent infection, eye development, hearing loss features, neurodevelopmental development, and congenital bone dysplasia were further discussed. CONCLUSIONS: Our results showed a new clinical finding of a contiguous deletion and duplication in chromosome 6p regions and suggested candidate genes associated with phenotypic features, such as FOXC1, SERPINB6, NRN1, TUBB2A, IRF4, and RIPK1.

18.
Lymphat Res Biol ; 21(5): 479-484, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37140566

RESUMO

Aim: To explore the effect of manual lymph drainage (MLD), compression bandaging (CB), or combined decongestive therapy (CDT), including MLD and CB, on stage 2 breast cancer-related lymphedema (BCRL). Methods: Sixty women with stage 2 BCRL were enrolled. They were randomly divided into the MLD group, the CB group or the CDT group. Each group, respectively, received MLD alone, CB alone, or CDT composed of MLD and CB, for 2 weeks. The volume and the local tissue water (LTW) of affected arms were measured before and after treatment. Arm circumferences were measured at 4 cm interval starting from the wrist to the shoulder with a tape measure. LTW was detected using the (tissue dielectric constant, TDC) method and was expressed as TDC value in two sites on the ventral midpoint of upper arm and forearm. Results: The volume of affected arms in each group after 2-weeks' treatment was lower than their baseline and the difference was statistically significant (p < 0.05). But there was no significant difference in volume change among three groups. The TDC value of the upper arm and forearm in the group CB and the group CDT decreased distinctly compared with baseline (p < 0.05). But the TDC value of the upper arm and forearm after MLD did not change (p > 0.05). Compared with the group MLD and the group CDT, the reduction of the TDC value in the group CB was more significant (p < 0.05). Conclusions: MLD or CB alone could effectively reduce the volume of affected arms for patients with stage 2 BCRL, and CB also could reduce the LTW more significantly. CDT did not seem to show an extra advantage. Therefore, CB may be the first choice for stage 2 BCRL. But for patients who are unwilling or intolerant to CB, MLD can be selected.

19.
Leukemia ; 37(3): 593-605, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36631623

RESUMO

Epigenetic regulators are frequently mutated in hematological malignancies including acute myeloid leukemia (AML). Thus, the identification and characterization of novel epigenetic drivers affecting AML biology holds potential to improve our basic understanding of AML and to uncover novel options for therapeutic intervention. To identify novel tumor suppressive epigenetic regulators in AML, we performed an in vivo short hairpin RNA (shRNA) screen in the context of CEBPA mutant AML. This identified the Histone 3 Lysine 4 (H3K4) demethylase KDM5C as a tumor suppressor, and we show that reduced Kdm5c/KDM5C expression results in accelerated growth both in human and murine AML cell lines, as well as in vivo in Cebpa mutant and inv(16) AML mouse models. Mechanistically, we show that KDM5C act as a transcriptional repressor through its demethylase activity at promoters. Specifically, KDM5C knockdown results in globally increased H3K4me3 levels associated with up-regulation of bivalently marked immature genes. This is accompanied by a de-differentiation phenotype that could be reversed by modulating levels of several direct and indirect downstream mediators. Finally, the association of KDM5C levels with long-term disease-free survival of female AML patients emphasizes the clinical relevance of our findings and identifies KDM5C as a novel female-biased tumor suppressor in AML.


Assuntos
Histona Desmetilases , Leucemia Mieloide Aguda , Animais , Feminino , Humanos , Camundongos , Diferenciação Celular , Linhagem Celular , Relevância Clínica , Histona Desmetilases/genética , Leucemia Mieloide Aguda/genética
20.
bioRxiv ; 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36711789

RESUMO

Bromodomain-containing Protein 4 (BRD4) is a transcriptional regulator which coordinates gene expression programs controlling cancer biology, inflammation, and fibrosis. In airway viral infection, non-toxic BRD4-specific inhibitors (BRD4i) block the release of pro-inflammatory cytokines and prevent downstream remodeling. Although the chromatin modifying functions of BRD4 in inducible gene expression have been extensively investigated, its roles in post-transcriptional regulation are not as well understood. Based on its interaction with the transcriptional elongation complex and spliceosome, we hypothesize that BRD4 is a functional regulator of mRNA processing. To address this question, we combine data-independent analysis - parallel accumulation-serial fragmentation (diaPASEF) with RNA-sequencing to achieve deep and integrated coverage of the proteomic and transcriptomic landscapes of human small airway epithelial cells exposed to viral challenge and treated with BRD4i. The transcript-level data was further interrogated for alternative splicing analysis, and the resulting data sets were correlated to identify pathways subject to post-transcriptional regulation. We discover that BRD4 regulates alternative splicing of key genes, including Interferon-related Developmental Regulator 1 ( IFRD1 ) and X-Box Binding Protein 1 ( XBP1 ), related to the innate immune response and the unfolded protein response, respectively. These findings extend the transcriptional elongation-facilitating actions of BRD4 in control of post-transcriptional RNA processing in innate signaling.

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