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1.
Sci Data ; 11(1): 739, 2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38972884

RESUMO

Cellular senescence (CS) is closely related to tumor progression. However, the studies about CS genes across human cancers have not explored the relationship between cancer senescence signature and telomere length. Additionally, single-cell analyses have not revealed the evolutionary trends of malignant cells and immune cells at the CS level. We defined a CS-associated signature, called "senescence signature", and found that patients with higher senescence signature had worse prognosis. Higher senescence signature was related to older age, higher genomic instability, longer telomeres, increased lymphocytic infiltration, higher pro-tumor immune infiltrates (Treg cells and MDSCs), and could predict responses to immune checkpoint inhibitor therapy. Single-cell analysis further reveals malignant cells and immune cells share a consistent evolutionary trend at the CS level. MAPK signaling pathway and apoptotic processes may play a key role in CS, and senescence signature may effectively predict sensitivity of MEK1/2 inhibitors, ERK1/2 inhibitors and BCL-2 family inhibitors. We also developed a new CS prediction model of cancer survival and established a portal website to apply this model ( https://bio-pub.shinyapps.io/cs_nomo/ ).


Assuntos
Senescência Celular , Neoplasias , Análise de Célula Única , Humanos , Neoplasias/imunologia , Imunossenescência , Instabilidade Genômica , Prognóstico , Multiômica
2.
PeerJ ; 12: e17302, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38737747

RESUMO

Background: Hepatitis B virus (HBV) infection poses a major public health problem worldwide. Bovine lactoferrin (bLf) is a natural product that can inhibit HBV, but the effect of iron saturation on its resistance to HBV is unknown. Aims: The purpose of this study is to investigate the impact of iron saturation of bLf against HBV. Methods: HepG2 cells were cultured in DMEM high glucose containing 10% inactivated fetal calf serum, at 37 °C, in 5% CO2. MTT method was used to detect the cytotoxicity of bLf to HepG2 cells. Apo-bLf and holo-bLf were prepared from bLf. Iron saturation of these proteins was determined by atomic absorption spectrophotometry. Non-cytotoxic concentrations of candidate proteins were used in anti-HBV tests. Fluorescent quantitative polymerase chain reaction was used to detect HBV-DNA. Results: The TC50 and TC0of bLf were 54.570 mg/ml and 1.997 mg/ml, respectively. The iron saturation of bLf, apo-bLf and holo-bLf were 10.29%, 8.42% and 85.32%, respectively. In this study, four non-cytotoxic concentrations of candidate proteins (1.5, 1.0, 0.5, and 0.1 mg/ml, respectively) were used to inhibit HBV in HepG2 cells. The results showed that 1.5 mg/ml bLf and 0.1 mg/ml holo-bLf effectively impaired the HBV-DNA amplification in HBV-infected HepG2 cells (P < 0.05). However, apo-bLf, and Fe3+ did not show the anti-HBV effects. Conclusion: A total of 1.5 mg/ml bLf and 0.1 mg/ml holo-bLf could inhibit HBV-DNA in HepG2 cells. Complete bLf structure, appropriate concentration and iron saturation of bLf are necessary conditions for anti-HBV effects.


Assuntos
Antivirais , Vírus da Hepatite B , Ferro , Lactoferrina , Lactoferrina/farmacologia , Humanos , Células Hep G2 , Vírus da Hepatite B/efeitos dos fármacos , Bovinos , Animais , Antivirais/farmacologia , Ferro/metabolismo , DNA Viral/efeitos dos fármacos
3.
J Pain Res ; 17: 1441-1451, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38628430

RESUMO

Background: Studies have shown that oral oxycontin tablets can be used for opioid titration. The European Society for Medical Oncology (ESMO) guidelines for adult cancer pain recommend opioid titration through the parenteral route, usually the intravenous or subcutaneous route. Patient-controlled subcutaneous analgesia (PCSA) with hydromorphone needs further evaluation for opioid titration. This prospective multicenter study was designed to compare the efficacy and safety of hydromorphone PCSA with oral oxycontin tablets for opioid titration of cancer pain. Patients and Methods: Eligible patients with cancer pain were randomly assigned in a 1:1 ratio to the PCSA group or the oxycontin group for dose titration. Different titration methods were given in both groups depending on whether the patient had an opioid tolerance. The primary endpoint of this study was time to successful titration (TST). Results: A total of 256 patients completed this study. The PCSA group had a significantly lower TST compared with the oxycontin group (median [95% confidence interval (CI)], 5.5[95% CI:2.5-11.5] hours vs.16.0 [95% CI:11.5-22.5] hours; p<0.001). The frequency (median; interquartile) of breakthrough pain (Btp) over 24 hours was significantly lower in the PCSA group (2.5;2.0-3.5) than in the oxycontin group.(3.0; 2.5-4.5) (p=0.04). The pain was evaluated by numeric rating scale (NRS) score at 12 hours after the start of titration. The pain score (median; interquartile) was significantly lower in the PCSA versus the oxycontin group (2.5;1.5-3.0) vs 4.5;3.0-6.0) (p=0.02). The equivalent dose of oral morphine (EDOM) for a successful titration was similar in both groups (p=0.29), but there was a significant improvement in quality of life (QoL) in both groups (p=0.03). No between-group difference in the incidence of opioid-related adverse effects was observed (p=0.32). Conclusion: Compared with oral oxycontin tablet, the use of PCSA with hydromorphone achieved a shorter titration duration for patients with cancer pain (p<0.001), without significantly increasing adverse events (p=0.32).

4.
Biosens Bioelectron ; 248: 115993, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38183788

RESUMO

Simultaneous, reliable, and ultra-sensitive analysis of promising miRNA biomarkers of colorectal cancer (CRC) in serum is critical for early diagnosis and prognosis of CRC. In this work, we proposed a novel 3D hierarchic assembly clusters-based SERS strategy with dual enrichment and enhancement designed for the ultrasensitive and quantitative analysis of two upregulated CRC-related miRNAs (miR-21 and miR-31). The biosensor contains the following: (1) SERS probe, Au nanocage@Au nanoparticles (AuNC@Au NPs) labeled with Raman reporters (RaRs). (2) magnetic capture unit, Ag-coated Fe3O4 magnetic nanoparticles (AgMNPs) modified with internal standard (IS). (3) signal amplify probes (SA probes) for the formation of hierarchic assembly clusters. Based on this sensing strategy, the intensity ratio IRaRs/IIS with Lg miRNAs presents a wide linear range (10 aM-100 pM) with a limit of detection of 3.46 aM for miR-21, 6.49 aM for miR-31, respectively. Moreover, the biosensor shows good specificity and anti-interference ability, and the reliability and repeatability of the strategy were then verified by practical detection of clinical serum. Finally, the biosensor can distinguish CRC cancer subjects from normal ones and guide the distinct tumor, lymph node, and metastasis (TNM) stages. Overall, benefiting from the face-to-face coupling of hierarchic assembly clusters, rapid magnetic enrichment and IS signal calibration of AgMNPs, the established biosensor achieves ultra-sensitive and simultaneous detection of dual miRNAs and opens potential avenues for prediction and staging of CRC.


Assuntos
Técnicas Biossensoriais , Neoplasias Colorretais , Nanopartículas Metálicas , MicroRNAs , Humanos , MicroRNAs/análise , Ouro , Reprodutibilidade dos Testes , Análise Espectral Raman , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Limite de Detecção
5.
Int J Biol Sci ; 20(2): 733-750, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38169726

RESUMO

Macrophage pyroptosis and neutrophil extracellular traps (NETs) play a critical role in sepsis pathophysiology; however, the role of macrophage pyroptosis in the regulation of NETs formation during sepsis is unknown. Here, we showed that macrophages transfer mitochondria to neutrophils through microvesicles following pyroptosis; this process induces mitochondrial dysfunction and triggers the induction of NETs formation through mitochondrial reactive oxygen species (mtROS)/Gasdermin D (GSDMD) axis. These pyroptotic macrophage-derived microvesicles can induce tissues damage, coagulation, and NETs formation in vivo. Disulfiram partly inhibits these effects in a mouse model of sepsis. Pyroptotic macrophage-derived microvesicles induce NETs formation through mitochondrial transfer, both in vitro and in vivo. Microvesicles-mediated NETs formation depends on the presence of GSDMD-N-expressing mitochondria in the microvesicles. This study elucidates a microvesicles-based pathway for NETs formation during sepsis and proposes a microvesicles-based intervention measure for sepsis management.


Assuntos
Armadilhas Extracelulares , Sepse , Camundongos , Animais , Armadilhas Extracelulares/metabolismo , Neutrófilos/metabolismo , Mitocôndrias/metabolismo , Macrófagos/metabolismo , Sepse/metabolismo
6.
Biochem Genet ; 62(1): 504-529, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37386336

RESUMO

Although immunotherapy is a valuable treatment for gastric cancer (GC), identifying the patients who would benefit most from this approach presents a challenge. In this study, GC patients were divided into two subtypes by consensus clustering according to T cell-mediated tumor killing related genes (TTKRGs), and there were significant differences in tumor-infiltrating immune cells, signaling pathways, and gene expression of immunomodulators and inhibitory immune checkpoints between the two subtypes. Then, we developed an individualized signature based on TTKRGs, and its clinical and predictive value in GC patients for chemotherapeutic and immunotherapeutic responses was assessed. We confirmed the expression levels of signature genes in GC tumor tissue using quantitative real-time polymerase chain reaction (qRT-PCR). Additionally, to improve the accuracy of GC prognosis predictions, we established a nomogram. We further identified some compounds as sensitive drugs targeting GC risk groups. The signature showed significant predictive ability across RNA-seq, microarray, and qRT-PCR cohorts, which could assist in predicting survival, immunotherapeutic and chemotherapeutic outcomes in GC patients.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , Neoplasias Gástricas/terapia , Prognóstico , Linfócitos T , Análise por Conglomerados , RNA-Seq
7.
Nat Prod Rep ; 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37873660

RESUMO

Covering: 2005 to August, 2023Polyamine-containing natural products (NPs) have been isolated from a wide range of terrestrial and marine organisms and most of them exhibit remarkable and diverse activities, including antimicrobial, antiprotozoal, antiangiogenic, antitumor, antiviral, iron-chelating, anti-depressive, anti-inflammatory, insecticidal, antiobesity, and antioxidant properties. Their extraordinary activities and potential applications in human health and agriculture attract increasing numbers of studies on polyamine-containing NPs. In this review, we summarized the source, structure, classification, bioactivities and biosynthesis of polyamine-containing NPs, focusing on the biosynthetic mechanism of polyamine itself and representative polyamine alkaloids, polyamine-containing siderophores with catechol/hydroxamate/hydroxycarboxylate groups, nonribosomal peptide-(polyketide)-polyamine (NRP-(PK)-PA), and NRP-PK-long chain poly-fatty amine (lcPFAN) hybrid molecules.

8.
J Med Chem ; 66(21): 14735-14754, 2023 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-37874867

RESUMO

Pseudomonas aeruginosa (P. aeruginosa) is well-known to cause biofilm-associated drug resistance and infections that often lead to treatment failure. Herein, we reported a dual-acting antibiofilm strategy by inhibiting both the bacterial quorum sensing system and the iron uptake system. A series of coumarin derivatives were synthesized and evaluated, and compound 4t was identified as the most effective biofilm inhibitor (IC50 = 3.6 µM). Further mechanistic studies have confirmed that 4t not only inhibits the QS systems but also competes strongly with pyoverdine as an iron chelator, causing an iron deficiency in P. aeruginosa. Additionally, 4t significantly improved the synergistic antibacterial effects of ciprofloxacin and tobramycin by more than 200-1000-fold compared to the single-dose antibiotic treatments. Therefore, our study has shown that 4t is a potentially novel antibacterial synergist candidate to treat bacterial infections.


Assuntos
Pseudomonas aeruginosa , Percepção de Quorum , Cumarínicos/farmacologia , Antibacterianos/farmacologia , Biofilmes , Ferro/farmacologia , Homeostase , Fatores de Virulência , Proteínas de Bactérias
9.
ACS Nano ; 17(20): 20073-20086, 2023 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-37792448

RESUMO

Despite the potential indicating role of tyrosinase (TYR) in cutaneous melanoma, how to capture the real changes of TYR in suspicious skin remains a major challenge. Unlike the traditional human serum test, this study reports a sensing platform that incorporates a wearable microneedle (MN) patch and trimetallic Au@Ag-Pt nanoparticles (NPs) for surface-enhanced Raman scattering (SERS) and colorimetric dual-mode detecting TYR in human skin in situ toward potential melanoma screening. In the presence of TYR, catechol immobilized on MN is preferentially oxidized to benzoquinone, which competitively impedes the interaction of MN and Au@Ag-Pt NPs, triggering the SERS-colorimetric signal reciprocal switch. Using a B16F10 mouse melanoma model, our platform is capable of noninvasively piercing the skin surface and detecting TYR levels before and during anti-PD-1 antibody treatment, which would be highly informative for prognostic judgment and illness monitoring of melanoma. Through in situ sensing for capturing the metabolic changes of TYR in advance, this platform was successfully applied to discriminate the melanoma subjects from skin moles and normal ones (p < 0.001), as well as screen potential melanoma from lactate dehydrogenase (LDH)-negative patients. Melanoma growth and prognosis can still be monitored through recording the continuous change of TYR levels. More importantly, the well-defined flexible and stretchable characteristics of the MN patch allow robustly adhering to the skin without inducing chemical or physical irritation. We believe this platform integrating MN-based in situ sensing, TYR responsiveness, and SERS/colorimetric dual-readout strategy will have high clinical importance in early diagnosis and monitoring of cutaneous melanoma.


Assuntos
Melanoma , Nanopartículas Metálicas , Neoplasias Cutâneas , Dispositivos Eletrônicos Vestíveis , Animais , Camundongos , Humanos , Melanoma/diagnóstico , Melanoma/metabolismo , Monofenol Mono-Oxigenase/metabolismo , Neoplasias Cutâneas/diagnóstico , Análise Espectral Raman , Ouro , Melanoma Maligno Cutâneo
11.
Molecules ; 28(19)2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37836780

RESUMO

Glutarimide-containing polyketides exhibiting potent antitumor and antimicrobial activities were encoded via conserved module blocks in various strains that favor the genomic mining of these family compounds. The bioinformatic analysis of the genome of Burkholderia gladioli ATCC 10248 showed a silent trans-AT PKS biosynthetic gene cluster (BGC) on chromosome 2 (Chr2C8), which was predicted to produce new glutarimide-containing derivatives. Then, the silent polyketide synthase gene cluster was successfully activated via in situ promoter insertion and heterologous expression. As a result, seven glutarimide-containing analogs, including five new ones, gladiofungins D-H (3-7), and two known gladiofungin A/gladiostatin (1) and 2 (named gladiofungin C), were isolated from the fermentation of the activated mutant. Their structures were elucidated through the analysis of HR-ESI-MS and NMR spectroscopy. The structural diversities of gladiofungins may be due to the degradation of the butenolide group in gladiofungin A (1) during the fermentation and extraction process. Bioactivity screening showed that 2 and 4 had moderate anti-inflammatory activities. Thus, genome mining combined with promoter engineering and heterologous expression were proved to be effective strategies for the pathway-specific activation of the silent BGCs for the directional discovery of new natural products.


Assuntos
Burkholderia gladioli , Piperidonas , Policetídeos , Burkholderia gladioli/genética , Burkholderia gladioli/metabolismo , Policetídeos/química , Piperidonas/química , Genômica , Família Multigênica
12.
Nat Commun ; 14(1): 6619, 2023 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-37857663

RESUMO

The broad bioactivities of nonribosomal peptides rely on increasing structural diversity. Genome mining of the Burkholderiales strain Schlegelella brevitalea DSM 7029 leads to the identification of a class of dodecapeptides, glidonins, that feature diverse N-terminal modifications and a uniform putrescine moiety at the C-terminus. The N-terminal diversity originates from the wide substrate selectivity of the initiation module. The C-terminal putrescine moiety is introduced by the unusual termination module 13, the condensation domain directly catalyzes the assembly of putrescine into the peptidyl backbone, and other domains are essential for stabilizing the protein structure. Swapping of this module to another two nonribosomal peptide synthetases leads to the addition of a putrescine to the C-terminus of related nonribosomal peptides, improving their hydrophilicity and bioactivity. This study elucidates the mechanism for putrescine addition and provides further insights to generate diverse and improved nonribosomal peptides by introducing a C-terminal putrescine.


Assuntos
Peptídeos , Putrescina , Peptídeos/genética , Peptídeos/química , Peptídeo Sintases/metabolismo
13.
Nat Metab ; 5(10): 1787-1802, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37679556

RESUMO

Neuroinflammatory microglia secrete cytokines to induce neurotoxic reactive astrocytes, which are one of the major causes of neuronal death. However, the intrinsic key regulators underlying neurotoxic reactive astrocytes induction are unknown. Here we show that the transmembrane protein 164 (TMEM164) is an early-response intrinsic factor that regulates neurotoxic astrocyte reactivity. TMEM164 overexpression inhibits the induction of neurotoxic reactive astrocytes, maintains normal astrocytic functions and suppresses neurotoxic reactive astrocyte-mediated neuronal death by decreasing the secretion of neurotoxic saturated lipids. Adeno-associated virus-mediated, astrocyte-specific TMEM164 overexpression in male and female mice prevents the induction of neurotoxic reactive astrocytes, dopaminergic neuronal loss and motor deficits in a Parkinson's disease model. Notably, brain-wide astrocyte-specific TMEM164 overexpression prevents the induction of neurotoxic reactive astrocytes, amyloid ß deposition, neurodegeneration and memory decline in the 5XFAD Alzheimer's disease mouse model, suggesting that TMEM164 could serve as a potential therapeutic target for neurodegenerative disorders.


Assuntos
Doença de Alzheimer , Astrócitos , Feminino , Camundongos , Animais , Masculino , Astrócitos/metabolismo , Peptídeos beta-Amiloides/metabolismo , Doença de Alzheimer/metabolismo , Microglia/metabolismo , Neurônios/metabolismo
15.
ACS Chem Neurosci ; 14(13): 2425-2442, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37339428

RESUMO

Neuropeptides with the C-terminal Wamide (Trp-NH2) are one of the last common ancestors of peptide families of eumetazoans and play various physiological roles. In this study, we sought to characterize the ancient Wamide peptides signaling systems in the marine mollusk Aplysia californica, i.e., APGWamide (APGWa) and myoinhibitory peptide (MIP)/Allatostatin B (AST-B) signaling systems. A common feature of protostome APGWa and MIP/AST-B peptides is the presence of a conserved Wamide motif in the C-terminus. Although orthologs of the APGWa and MIP signaling systems have been studied to various extents in annelids or other protostomes, no complete signaling systems have yet been characterized in mollusks. Here, through bioinformatics, molecular and cellular biology, we identified three receptors for APGWa, namely, APGWa-R1, APGWa-R2, and APGWa-R3. The EC50 values for APGWa-R1, APGWa-R2, and APGWa-R3 are 45, 2100, and 2600 nM, respectively. For the MIP signaling system, we predicted 13 forms of peptides, i.e., MIP1-13 that could be generated from the precursor identified in our study, with MIP5 (WKQMAVWa) having the largest number of copies (4 copies). Then, a complete MIP receptor (MIPR) was identified and the MIP1-13 peptides activated the MIPR in a dose-dependent manner, with EC50 values ranging from 40 to 3000 nM. Peptide analogs with alanine substitution experiments demonstrated that the Wamide motif at the C-terminus is necessary for receptor activity in both the APGWa and MIP systems. Moreover, cross-activity between the two signaling systems showed that MIP1, 4, 7, and 8 ligands could activate APGWa-R1 with a low potency (EC50 values: 2800-22,000 nM), which further supported that the APGWa and MIP signaling systems are somewhat related. In summary, our successful characterization of Aplysia APGWa and MIP signaling systems represents the first example in mollusks and provides an important basis for further functional studies in this and other protostome species. Moreover, this study may be useful for elucidating and clarifying the evolutionary relationship between the two Wamide signaling systems (i.e., APGWa and MIP systems) and their other extended neuropeptide signaling systems.


Assuntos
Aplysia , Neuropeptídeos , Animais , Sequência de Aminoácidos , Moluscos , Peptídeos
16.
Mol Genet Genomics ; 298(4): 823-836, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37059908

RESUMO

Coronavirus 2019 (COVID-19) is a complex disease that affects billions of people worldwide. Currently, effective etiological treatment of COVID-19 is still lacking; COVID-19 also causes damages to various organs that affects therapeutics and mortality of the patients. Surveillance of the treatment responses and organ injury assessment of COVID-19 patients are of high clinical value. In this study, we investigated the characteristic fragmentation patterns and explored the potential in tissue injury assessment of plasma cell-free DNA in COVID-19 patients. Through recruitment of 37 COVID-19 patients, 32 controls and analysis of 208 blood samples upon diagnosis and during treatment, we report gross abnormalities in cfDNA of COVID-19 patients, including elevated GC content, altered molecule size and end motif patterns. More importantly, such cfDNA fragmentation characteristics reflect patient-specific physiological changes during treatment. Further analysis on cfDNA tissue-of-origin tracing reveals frequent tissue injuries in COVID-19 patients, which is supported by clinical diagnoses. Hence, our work demonstrates and extends the translational merit of cfDNA fragmentation pattern as valuable analyte for effective treatment monitoring, as well as tissue injury assessment in COVID-19.


Assuntos
COVID-19 , Ácidos Nucleicos Livres , Humanos , COVID-19/diagnóstico , Ácidos Nucleicos Livres/genética
17.
Front Pharmacol ; 14: 1132066, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37021048

RESUMO

The vasopressin/oxytocin signaling system is present in both protostomes and deuterostomes and plays various physiological roles. Although there were reports for both vasopressin-like peptides and receptors in mollusc Lymnaea and Octopus, no precursor or receptors have been described in mollusc Aplysia. Here, through bioinformatics, molecular and cellular biology, we identified both the precursor and two receptors for Aplysia vasopressin-like peptide, which we named Aplysia vasotocin (apVT). The precursor provides evidence for the exact sequence of apVT, which is identical to conopressin G from cone snail venom, and contains 9 amino acids, with two cysteines at position 1 and 6, similar to nearly all vasopressin-like peptides. Through inositol monophosphate (IP1) accumulation assay, we demonstrated that two of the three putative receptors we cloned from Aplysia cDNA are true receptors for apVT. We named the two receptors as apVTR1 and apVTR2. We then determined the roles of post-translational modifications (PTMs) of apVT, i.e., the disulfide bond between two cysteines and the C-terminal amidation on receptor activity. Both the disulfide bond and amidation were critical for the activation of the two receptors. Cross-activity with conopressin S, annetocin from an annelid, and vertebrate oxytocin showed that although all three ligands can activate both receptors, the potency of these peptides differed depending on their residue variations from apVT. We, therefore, tested the roles of each residue through alanine substitution and found that each substitution could reduce the potency of the peptide analog, and substitution of the residues within the disulfide bond tended to have a larger impact on receptor activity than the substitution of those outside the bond. Moreover, the two receptors had different sensitivities to the PTMs and single residue substitutions. Thus, we have characterized the Aplysia vasotocin signaling system and showed how the PTMs and individual residues in the ligand contributed to receptor activity.

18.
Arthritis Rheumatol ; 75(8): 1381-1394, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36862399

RESUMO

OBJECTIVE: Disruption of B cell homeostasis and subsequent dominance of effector B cell subsets are critical for the development of systemic lupus erythematosus (SLE). Revealing the key intrinsic regulators involved in the homeostatic control of B cells has important therapeutic value for SLE. This study was undertaken to determine the regulatory role of the transcription factor Pbx1 in B cell homeostasis and lupus pathogenesis. METHODS: We constructed mice with B cell-specific deletion of Pbx1. T cell-dependent and T cell-independent humoral responses were induced by intraperitoneal injection of nitrophenyl-containing hapten (NP) conjugated to keyhole limpet hemocyanin or NP-Ficoll. The regulatory effects of Pbx1 on autoimmunity were observed in a Bm12-induced lupus murine model. We investigated mechanisms of Pbx1 using RNA sequencing, the cleavage under targets and tagmentation assay, and chromatin immunoprecipitation-quantitative polymerase chain reaction assay. We transduced B cells from SLE patients with plasmids that overexpressed PBX1 to explore the in vitro therapeutic efficacy of PBX1. RESULTS: Pbx1 was specifically down-regulated in autoimmune B cells and negatively correlated with disease activity. The deficiency of Pbx1 in B cells resulted in excessive humoral responses following immunization. In the Bm12-induced lupus model, mice with B cell-specific Pbx1 deficiency displayed enhancements in germinal center responses, plasma cell differentiation, and autoantibody production. Pbx1-deficient B cells had increased survival and proliferative advantages after activation. Pbx1 regulated genetic programs by directly targeting critical components of the proliferation and apoptosis pathways. In SLE patients, PBX1 expression was negatively correlated with effector B cell expansion; when PBX1 expression was enforced, the survival and proliferative capacity of SLE B cells were attenuated. CONCLUSION: Our study reveals the regulatory function and mechanism of Pbx1 in adjusting B cell homeostasis and highlights Pbx1 as a therapeutic target in SLE.


Assuntos
Autoimunidade , Lúpus Eritematoso Sistêmico , Camundongos , Animais , Fatores de Transcrição/genética , Regulação da Expressão Gênica , Linfócitos B , Fator de Transcrição 1 de Leucemia de Células Pré-B/genética , Fator de Transcrição 1 de Leucemia de Células Pré-B/metabolismo
19.
ACS Synth Biol ; 12(4): 971-977, 2023 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-36988632

RESUMO

Engineering the biosynthetic pathways of complex natural products is a significant approach to obtain derivatives with improved properties. Here, we constructed a streamlined engineered biosynthesis system of myxobacterium-derived complex polyketide disorazol in a heterologous host, Burkholderia thailandensis E264. Inactivation of dehydratase domains in the disorazol biosynthetic pathway led to the production of two hydroxylated derivatives. Module deletion allowed the generation of an unnatural derivative with a truncated macrolactone ring, and the ACP-KS linker was the optimal fusion region for module deletion in this trans-AT polyketide synthase. These disorazol derivatives showed different activities against human cancer cell lines ranging from the nanomolar to micromolar level, suggesting the primary structure-activity relationship. The PKS engineering enables structural derivatization of disorazol, facilitating the in-depth engineered biosynthesis of polyketides.


Assuntos
Policetídeos , Humanos , Policetídeos/metabolismo , Policetídeo Sintases/genética , Policetídeo Sintases/metabolismo , Relação Estrutura-Atividade
20.
Anal Chem ; 95(14): 5955-5966, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-36916246

RESUMO

Ultra-sensitive detection of cancer-related biomarkers in serum is of great significance for early diagnosis, treatment, prognosis, and staging of cancer. In this work, we proposed a surface-enhanced Raman scattering and fluorescence (SERS/FL) dual-mode biosensor for hepatocellular carcinoma (HCC)-related miRNA (miR-224) detection using the composition of well-arranged Au nanoarrays (Au NAs) substrate coupled with the target-catalyzed hairpin assembly (CHA) strategy. The hot spots densely and uniformly distributed on the Au array offers considerably enhanced and reproducible SERS signals, along with their wide and open surface to facilitate miR-224 adsorption. By this sensing strategy, the target miR-224 can be detected in a wide linear range (1 fM to 1 nM) with a limit of detection of 0.34 fM in the SERS mode and 0.39 fM in the FL mode. Meanwhile, this biosensor with exceptional specificity and anti-interference ability can discriminate target miR-224 from other interference miRNAs. Practical analysis of human blood samples also demonstrated considerable reliability and repeatability of our developed strategy. Furthermore, this biosensor can distinguish HCC cancer subjects from normal ones and monitor HCC patients before and after hepatectomy as well as guide the distinct Barcelona clinic liver cancer (BCLC) stages. Overall, benefiting from a well-arranged Au nanoarray, CHA amplification strategy, and SERS/metal enhanced fluorescence effect, this established biosensor opens new avenues for the early prediction, warning, monitoring, and staging of HCC.


Assuntos
Técnicas Biossensoriais , Carcinoma Hepatocelular , Neoplasias Hepáticas , Nanopartículas Metálicas , MicroRNAs , Humanos , Carcinoma Hepatocelular/diagnóstico , Ouro/química , Limite de Detecção , Neoplasias Hepáticas/diagnóstico , Nanopartículas Metálicas/química , Nanoestruturas , Reprodutibilidade dos Testes , Análise Espectral Raman , Corantes Fluorescentes/química
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