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1.
Cell ; 184(4): 943-956.e18, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33571432

RESUMO

Dopamine receptors, including D1- and D2-like receptors, are important therapeutic targets in a variety of neurological syndromes, as well as cardiovascular and kidney diseases. Here, we present five cryoelectron microscopy (cryo-EM) structures of the dopamine D1 receptor (DRD1) coupled to Gs heterotrimer in complex with three catechol-based agonists, a non-catechol agonist, and a positive allosteric modulator for endogenous dopamine. These structures revealed that a polar interaction network is essential for catecholamine-like agonist recognition, whereas specific motifs in the extended binding pocket were responsible for discriminating D1- from D2-like receptors. Moreover, allosteric binding at a distinct inner surface pocket improved the activity of DRD1 by stabilizing endogenous dopamine interaction at the orthosteric site. DRD1-Gs interface revealed key features that serve as determinants for G protein coupling. Together, our study provides a structural understanding of the ligand recognition, allosteric regulation, and G protein coupling mechanisms of DRD1.


Assuntos
Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Receptores de Dopamina D1/metabolismo , Transdução de Sinais , Regulação Alostérica , Sítio Alostérico , Motivos de Aminoácidos , Sequência de Aminoácidos , Sítios de Ligação , Catecóis/metabolismo , Microscopia Crioeletrônica , Fenoldopam/química , Fenoldopam/farmacologia , Subunidades alfa Gs de Proteínas de Ligação ao GTP/química , Subunidades alfa Gs de Proteínas de Ligação ao GTP/ultraestrutura , Células HEK293 , Humanos , Ligantes , Modelos Moleculares , Multimerização Proteica , Receptores de Dopamina D1/química , Receptores de Dopamina D1/ultraestrutura , Receptores de Dopamina D2/metabolismo , Homologia Estrutural de Proteína
2.
Nature ; 604(7907): 771-778, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35418677

RESUMO

Adhesion G protein-coupled receptors (aGPCRs) constitute an evolutionarily ancient family of receptors that often undergo autoproteolysis to produce α and ß subunits1-3. A tethered agonism mediated by the 'Stachel sequence' of the ß subunit has been proposed to have central roles in aGPCR activation4-6. Here we present three cryo-electron microscopy structures of aGPCRs coupled to the Gs heterotrimer. Two of these aGPCRs are activated by tethered Stachel sequences-the ADGRG2-ß-Gs complex and the ADGRG4-ß-Gs complex (in which ß indicates the ß subunit of the aGPCR)-and the other is the full-length ADGRG2 in complex with the exogenous ADGRG2 Stachel-sequence-derived peptide agonist IP15 (ADGRG2(FL)-IP15-Gs). The Stachel sequences of both ADGRG2-ß and ADGRG4-ß assume a U shape and insert deeply into the seven-transmembrane bundles. Constituting the FXφφφXφ motif (in which φ represents a hydrophobic residue), five residues of ADGRG2-ß or ADGRG4-ß extend like fingers to mediate binding to the seven-transmembrane domain and activation of the receptor. The structure of the ADGRG2(FL)-IP15-Gs complex reveals the structural basis for the improved binding affinity of IP15 compared with VPM-p15 and indicates that rational design of peptidic agonists could be achieved by exploiting aGPCR-ß structures. By converting the 'finger residues' to acidic residues, we develop a method to generate peptidic antagonists towards several aGPCRs. Collectively, our study provides structural and biochemical insights into the tethered activation mechanism of aGPCRs.


Assuntos
Peptídeos , Receptores Acoplados a Proteínas G , Microscopia Crioeletrônica , Humanos , Peptídeos/metabolismo , Domínios Proteicos , Receptores Acoplados a Proteínas G/metabolismo
3.
Nature ; 589(7843): 620-626, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33408414

RESUMO

Adhesion G-protein-coupled receptors (GPCRs) are a major family of GPCRs, but limited knowledge of their ligand regulation or structure is available1-3. Here we report that glucocorticoid stress hormones activate adhesion G-protein-coupled receptor G3 (ADGRG3; also known as GPR97)4-6, a prototypical adhesion GPCR. The cryo-electron microscopy structures of GPR97-Go complexes bound to the anti-inflammatory drug beclomethasone or the steroid hormone cortisol revealed that glucocorticoids bind to a pocket within the transmembrane domain. The steroidal core of glucocorticoids is packed against the 'toggle switch' residue W6.53, which senses the binding of a ligand and induces activation of the receptor. Active GPR97 uses a quaternary core and HLY motif to fasten the seven-transmembrane bundle and to mediate G protein coupling. The cytoplasmic side of GPR97 has an open cavity, where all three intracellular loops interact with the Go protein, contributing to the high basal activity of GRP97. Palmitoylation at the cytosolic tail of the Go protein was found to be essential for efficient engagement with GPR97 but is not observed in other solved GPCR complex structures. Our work provides a structural basis for ligand binding to the seven-transmembrane domain of an adhesion GPCR and subsequent G protein coupling.


Assuntos
Microscopia Crioeletrônica , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/química , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Glucocorticoides/química , Glucocorticoides/metabolismo , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/ultraestrutura , Sítios de Ligação , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/ultraestrutura , Humanos , Ligantes , Lipoilação , Modelos Moleculares , Ligação Proteica , Receptores Acoplados a Proteínas G/metabolismo
4.
Nat Chem Biol ; 19(4): 468-477, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36635564

RESUMO

Membrane dynamics are important to the integrity and function of mitochondria. Defective mitochondrial fusion underlies the pathogenesis of multiple diseases. The ability to target fusion highlights the potential to fight life-threatening conditions. Here we report a small molecule agonist, S89, that specifically promotes mitochondrial fusion by targeting endogenous MFN1. S89 interacts directly with a loop region in the helix bundle 2 domain of MFN1 to stimulate GTP hydrolysis and vesicle fusion. GTP loading or competition by S89 dislodges the loop from the GTPase domain and unlocks the molecule. S89 restores mitochondrial and cellular defects caused by mitochondrial DNA mutations, oxidative stress inducer paraquat, ferroptosis inducer RSL3 or CMT2A-causing mutations by boosting endogenous MFN1. Strikingly, S89 effectively eliminates ischemia/reperfusion (I/R)-induced mitochondrial damage and protects mouse heart from I/R injury. These results reveal the priming mechanism for MFNs and provide a therapeutic strategy for mitochondrial diseases when additional mitochondrial fusion is beneficial.


Assuntos
Dinâmica Mitocondrial , Proteínas de Transporte da Membrana Mitocondrial , Camundongos , Animais , Proteínas de Transporte da Membrana Mitocondrial/análise , Proteínas de Transporte da Membrana Mitocondrial/química , Proteínas de Transporte da Membrana Mitocondrial/genética , Mitocôndrias , Hidrólise , Guanosina Trifosfato/análise , Guanosina Trifosfato/farmacologia , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/análise , Proteínas Mitocondriais/farmacologia
5.
J Immunol ; 211(6): 964-980, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37578390

RESUMO

Teleost B cells are primitive lymphocytes with both innate and adaptive immune functions. However, the heterogeneity and differentiation trajectory of teleost B cells remain largely unknown. In this study, the landscape of grass carp IgM+ (gcIgM+) B cells was revealed by single-cell RNA sequencing. The results showed that gcIgM+ B cells mainly comprise six populations: (im)mature B cells, innate B cells, proliferating B cells, plasma cells, CD22+ cells, and CD34+ cells, among which innate B cells and proliferating B cells were uncommon B cell subsets with, to our knowledge, new characteristics. Remarkably, three functional IgMs were discovered in grass carp, and a significant percentage of gcIgM+ B cells, especially plasma cells, expressed multiple Igµ genes (Igµ1, Igµ2, and/or Igµ3). More importantly, through single-cell sorting combined with Sanger sequencing, we found that distinct VHDJH recombination patterns of Igµ genes were present in single IgM+ B cells, indicating that individual teleost B cells might produce multiple Abs by coexpressing rearranged IgM subclass genes. Moreover, the percentage of IgM1highIgM2highIgM3high plasma cells increased significantly after bacterial infection, suggesting that individual plasma cells might tend to produce multiple IgMs to resist the infection in teleost fish. In summary, to our knowledge, this study not only helps to uncover the unique heterogeneity of B cells in early vertebrates but also provided significant new evidence supporting the recently proposed "one cell-multiple Abs" paradigm, challenging the classical rule of "one cell-one Ab."


Assuntos
Infecções Bacterianas , Carpas , Doenças dos Peixes , Animais , Imunidade Inata/genética , Proteínas de Peixes/genética , Imunoglobulina M , Homeostase
6.
J Org Chem ; 89(5): 3279-3291, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38377542

RESUMO

The construction of 3,4-dihydroquinolone derivatives has attracted a considerable amount of attention due to their extensive applications in medicinal chemistry. In this study, we present the Pd-catalyzed [4+2] cycloaddition of vinyl benzoxazinanones with α-alkylidene succinimides for the efficient synthesis of 3,4-dihydroquinolones. This approach presents numerous advantages, including the ready availability of starting materials, mild reaction conditions without the use of additional bases, and a wide range of substrates. In particular, all of the desired products can be easily afforded in high yields (≤99%) and excellent diastereoselectivities (>20:1). The practicality and reliability of this strategy were demonstrated by the successful scale-up synthesis and subsequent straightforward synthetic transformations.

7.
Fish Shellfish Immunol ; 150: 109649, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38797336

RESUMO

In mammals, CD4 is found to be expressed on T cells and innate immune cells, however, teleost cells bearing CD4 have not been well identified and characterized. In this study, we identified two different CD4-1+ cell subsets in grass carp (Ctenopharyngodon idella): CD4-1+ lymphocytes (Lym) and CD4-1+ myeloid cells (Mye), both of which had the highest proportions in the head kidney. The mRNA expression analysis showed that CD4-1, CD4-2, TCRß, CD3γ/δ, and LCK1 are highly expressed in CD4-1+ Lym and also expressed in CD4-1+ Mye. Furthermore, we found that CD4-1+ Lym have a Lym morphology and highly express T-cell cytokines, suggesting that they are CD4+ T cells equivalent to mammalian Th cells. On the other hand, CD4-1+ Mye were found to have a morphology of macrophage and highly express macrophage marker gene MCSFR, indicating that they are macrophages. In addition, functional analysis revealed that CD4-1+ Mye possess phagocytic ability and great antigen-processing ability. Taken together, our study sheds further light on the composition and function of CD4+ cells in teleost fish.


Assuntos
Carpas , Proteínas de Peixes , Animais , Carpas/imunologia , Carpas/genética , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Linfócitos T CD4-Positivos/imunologia , Antígenos CD4/genética , Antígenos CD4/imunologia , Antígenos CD4/metabolismo , Rim Cefálico/imunologia , Rim Cefálico/citologia , Células Mieloides/imunologia , Imunidade Inata/genética
8.
J Immunol ; 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36426989

RESUMO

Complement peptides C3a, C4a, and C5a are important components of innate immunity in vertebrates. Although they diverged from a common ancestor, only C3a and C4a can act as antibacterial peptides in Homo sapiens, suggesting that C5a has evolved into a purely chemotactic molecule; however, the antibacterial properties of C3a, C4a, and C5a across vertebrates still require elucidation. In this article, we show that, unlike those in H. sapiens, Mus musculus C3a, C4a, and C5a all possess antibacterial activities, implying that the antibacterial properties of C3a, C4a, and C5a have evolved divergently in vertebrates. The extremely different net charge, a key factor determining the antibacterial activities of cationic antimicrobial peptides, of vertebrate C3a, C4a, and C5a supports this speculation. Moreover, the antibacterial activity of overlapping peptides covering vertebrate C3a, C4a, and C5a further strongly supports the speculation, because their activity is positively correlated with the net charge of source molecules. Notably, the structures of C3a, C4a, and C5a are conserved in vertebrates, and the inactive overlapping peptides can become antibacterial peptides if mutated to possess enough net positive charges, indicating that net charge is the only factor determining the antibacterial properties of vertebrate C3a, C4a, and C5a. More importantly, many vertebrate C3a-, C4a-, and C5a-derived peptides possess high antibacterial activities yet exhibit no hemolytic activities, suggesting the application potential in anti-infective therapy. Taken together, our findings reveal that vertebrate C3a, C4a, and C5a are all sources of antibacterial peptides that will facilitate the design of excellent peptide antibiotics.

9.
J Immunol ; 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36280254

RESUMO

Complement peptides C3a, C4a, and C5a are important components of innate immunity in vertebrates. Although they diverged from a common ancestor, only C3a and C4a can act as antibacterial peptides in Homo sapiens, suggesting that C5a has evolved into a purely chemotactic molecule; however, the antibacterial properties of C3a, C4a, and C5a across vertebrates still require elucidation. In this article, we show that, unlike those in H. sapiens, Mus musculus C3a, C4a, and C5a all possess antibacterial activities, implying that the antibacterial properties of C3a, C4a, and C5a have evolved divergently in vertebrates. The extremely different net charge, a key factor determining the antibacterial activities of cationic antimicrobial peptides, of vertebrate C3a, C4a, and C5a supports this speculation. Moreover, the antibacterial activity of overlapping peptides covering vertebrate C3a, C4a, and C5a further strongly supports the speculation, because their activity is positively correlated with the net charge of source molecules. Notably, the structures of C3a, C4a, and C5a are conserved in vertebrates, and the inactive overlapping peptides can become antibacterial peptides if mutated to possess enough net positive charges, indicating that net charge is the only factor determining the antibacterial properties of vertebrate C3a, C4a, and C5a. More importantly, many vertebrate C3a-, C4a-, and C5a-derived peptides possess high antibacterial activities yet exhibit no hemolytic activities, suggesting the application potential in anti-infective therapy. Taken together, our findings reveal that vertebrate C3a, C4a, and C5a are all sources of antibacterial peptides that will facilitate the design of excellent peptide antibiotics.

10.
Macromol Rapid Commun ; 45(15): e2400151, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38635599

RESUMO

The rapid growth of the Internet of Things and wearable sensors has led to advancements in monitoring technology in the field of health. One such advancement is the development of wearable respiratory sensors, which offer a new approach to real-time respiratory monitoring compared to traditional methods. However, the energy consumption of these sensors raises concerns about environmental pollution. To address the issue, this study proposes the use of a triboelectric nanogenerator (TENG) as a sustainable energy source. The electrical conductivity of the TENG is improved by incorporating chitosan and carbon nanotubes, with the added benefit of chitosan's biodegradability reducing negative environmental impact. A wireless intelligent respiratory monitoring system (WIRMS) is then introduced, which utilizes a degradable triboelectric nanogenerator for real-time respiratory monitoring, diagnosis, and prevention of obstructive respiratory diseases. WIRMS offers stable and highly accurate respiratory information monitoring, while enabling real-time and nondestructive transmission of information. In addition, machine learning technology is used for sleep respiration state analysis. The potential applications of WIRMS extend to wearables, medical monitoring and sports monitoring, thereby presenting innovative ideas for modern medical and sports monitoring.


Assuntos
Nanotubos de Carbono , Dispositivos Eletrônicos Vestíveis , Tecnologia sem Fio , Tecnologia sem Fio/instrumentação , Humanos , Nanotubos de Carbono/química , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Sono/fisiologia , Esportes , Quitosana/química , Nanotecnologia/instrumentação , Nanotecnologia/métodos , Respiração , Condutividade Elétrica , Fontes de Energia Elétrica
11.
J Sports Sci Med ; 23(1): 156-176, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38455430

RESUMO

The primary objective of this systematic review with meta-analysis is to methodically discern and compare the impact of diverse warm-up strategies, including both static and dynamic stretching, as well as post-activation potentiation techniques, on the immediate performance of gymnasts. Adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, this paper evaluated studies that examined the gymnasts' performance after different warm-up strategies namely stretching (static [SS] or dynamic), vibration platforms (VP) or post-activation, in comparison to control conditions (e.g., mixed warm-up routines; no warm-up). The principal outcomes were centered on technical performance metrics (e.g., split, gymnastic jumps) and physical performance metrics (e.g., squat jump, countermovement jump, drop jump, balance, range of motion). Methodological assessments of the included studies were conducted using the Downs and Black Checklist. From the initial search across PubMed, Scopus, and the Web of Science databases, a total of 591 titles were retrieved, and 19 articles were ultimately incorporated in the analysis. The results revealed a non-significant differences (p > 0.05) between the SS condition and control conditions in squat jump performance, countermovement jump and gymnastic technical performance (e.g., split; split jump). Despite the difference in warm-up strategies and outcomes analyzed, the results suggest that there is no significant impairment of lower-limb power after SS. Additionally, technical elements dependent on flexibility appear to be enhanced by SS. Conversely, dynamic stretching and VP seem to be more effective for augmenting power-related and dynamic performance in gymnasts.


Assuntos
Exercícios de Alongamento Muscular , Exercício de Aquecimento , Humanos , Ginástica/fisiologia , Extremidade Inferior , Amplitude de Movimento Articular/fisiologia
12.
Rev Cardiovasc Med ; 24(10): 305, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39077586

RESUMO

Background: The atherogenic index of plasma (AIP), determined by the logarithmic transformation of the ratio of triglyceride (TG) and high-density lipoprotein cholesterol (HDL-C), was found to be a marker of cardiovascular disease. We sought to investigate the correlation between the atherogenic AIP and coronary collateral circulation (CCC) formation in chronic total occlusive (CTOs) patients. Methods: This retrospective cohort study included 665 non-CTOs and 345 CTOs patients. CTOs were divided into 206 CCC poor formation patients and 139 CCC good formation patients according to the Cohen-Rentrop grade. Spearman correlation analysis was carried out to obtain the relationship between AIP and the Rentrop grade. We used multivariate logistic regression analysis to assess CTOs and CCC poor formation risk factors. Receiver operating characteristic (ROC) curves were used to determine the optimal threshold for AIP to predict CTOs and CCC poor formation. The predicted increment of AIP on CTOs and CCC poor formation was evaluated by calculating the Net Reclassification Index (NRI) and the Integrated Discriminant Index (IDI). Results: AIP in CTOs was significantly elevated compared to non-CTOs patients [(1.55 (1.02, 2.59)) vs (1.26 (0.82, 1.90)), p < 0.001] AIP in the CCC poor formation group was significantly higher than that in the CCC good formation group [(1.73 (1.12, 2.90)) vs (1.37 (0.84, 2.13)), p = 0.002]. There was a negative correlation between AIP and the Rentrop grade (r = -0.145, p = 0.007). The results of multivariate logistic regression revealed that AIP was an independent predictor of CTOs (OR = 4.371, 95% CI: 2.436-7.844, p < 0.001) and CCC poor formation (OR = 3.749, 95% CI: 1.628-8.635, p = 0.002). In the ROC analysis, the area under the curve of AIP for identifying CTOs and CCC poor formation was 0.596 (OR = 3.680, 95% CI: 1.490-9.090, p = 0.005) and 0.597 (95% CI: 0.535-0.658, p = 0.002), respectively. Conclusions: Contrary to previous research, we found that AIP is a moderate but not powerful indicator for detecting both CTO patients and poor CCC formation.

13.
J Neuroinflammation ; 19(1): 244, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36195881

RESUMO

BACKGROUND: Neuropathic pain is still a challenge for clinical treatment as a result of the comprehensive pathogenesis. Although emerging evidence demonstrates the pivotal role of glial cells in regulating neuropathic pain, the role of Schwann cells and their underlying mechanisms still need to be uncovered. Pannexin 1 (Panx 1), an important membrane channel for the release of ATP and inflammatory cytokines, as well as its activation in central glial cells, contributes to pain development. Here, we hypothesized that Schwann cell Panx 1 participates in the regulation of neuroinflammation and contributes to neuropathic pain. METHODS: A mouse model of chronic constriction injury (CCI) in CD1 adult mice or P0-Cre transgenic mice, and in vitro cultured Schwann cells were used. Intrasciatic injection with Panx 1 blockers or the desired virus was used to knock down the expression of Panx 1. Mechanical and thermal sensitivity was assessed using Von Frey and a hot plate assay. The expression of Panx 1 was measured using qPCR, western blotting, and immunofluorescence. The production of cytokines was monitored through qPCR and enzyme-linked immunosorbent assay (ELISA). Panx1 channel activity was detected by ethidium bromide (EB) uptake. RESULTS: CCI induced persistent neuroinflammatory responses and upregulation of Panx 1 in Schwann cells. Intrasciatic injection of Panx 1 blockers, carbenoxolone (CBX), probenecid, and Panx 1 mimetic peptide (10Panx) effectively reduced mechanical and heat hyperalgesia. Probenecid treatment of CCI-induced mice significantly reduced Panx 1 expression in Schwann cells, but not in dorsal root ganglion (DRG). In addition, Panx 1 knockdown in Schwann cells with Panx 1 shRNA-AAV in P0-Cre mice significantly reduced CCI-induced neuropathic pain. To determine whether Schwann cell Panx 1 participates in the regulation of neuroinflammation and contributes to neuropathic pain, we evaluated its effect in LPS-treated Schwann cells. We found that inhibition of Panx 1 via CBX and Panx 1-siRNA effectively attenuated the production of selective cytokines, as well as its mechanism of action being dependent on both Panx 1 channel activity and its expression. CONCLUSION: In this study, we found that CCI-related neuroinflammation correlates with Panx 1 activation in Schwann cells, indicating that inhibition of Panx 1 channels in Schwann cells reduces neuropathic pain through the suppression of neuroinflammatory responses.


Assuntos
Carbenoxolona , Neuralgia , Trifosfato de Adenosina/farmacologia , Animais , Carbenoxolona/farmacologia , Carbenoxolona/uso terapêutico , Conexinas/genética , Conexinas/metabolismo , Citocinas/metabolismo , Etídio/metabolismo , Etídio/farmacologia , Etídio/uso terapêutico , Hiperalgesia/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Neuralgia/metabolismo , Probenecid/metabolismo , Probenecid/farmacologia , Probenecid/uso terapêutico , RNA Interferente Pequeno/metabolismo , Células de Schwann
14.
Acta Pharmacol Sin ; 43(2): 470-482, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33850276

RESUMO

Aerobic glycolysis, also known as the Warburg effect, is a hallmark of cancer cell glucose metabolism and plays a crucial role in the activation of various types of immune cells. Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) catalyzes the conversion of D-glyceraldehyde 3-phosphate to D-glycerate 1,3-bisphosphate in the 6th critical step in glycolysis. GAPDH exerts metabolic flux control during aerobic glycolysis and therefore is an attractive therapeutic target for cancer and autoimmune diseases. Recently, GAPDH inhibitors were reported to function through common suicide inactivation by covalent binding to the cysteine catalytic residue of GAPDH. Herein, by developing a high-throughput enzymatic screening assay, we discovered that the natural product 1,2,3,4,6-penta-O-galloyl-ß-D-glucopyranose (PGG) is an inhibitor of GAPDH with Ki = 0.5 µM. PGG blocks GAPDH activity by a reversible and NAD+ and Pi competitive mechanism, suggesting that it represents a novel class of GAPDH inhibitors. In-depth hydrogen deuterium exchange mass spectrometry (HDX-MS) analysis revealed that PGG binds to a region that disrupts NAD+ and inorganic phosphate binding, resulting in a distal conformational change at the GAPDH tetramer interface. In addition, structural modeling analysis indicated that PGG probably reversibly binds to the center pocket of GAPDH. Moreover, PGG inhibits LPS-stimulated macrophage activation by specific downregulation of GAPDH-dependent glucose consumption and lactate production. In summary, PGG represents a novel class of GAPDH inhibitors that probably reversibly binds to the center pocket of GAPDH. Our study sheds new light on factors for designing a more potent and specific inhibitor of GAPDH for future therapeutic applications.


Assuntos
Gliceraldeído-3-Fosfato Desidrogenases/antagonistas & inibidores , Taninos Hidrolisáveis/farmacologia , Animais , Avaliação Pré-Clínica de Medicamentos/métodos , Glucose/metabolismo , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/antagonistas & inibidores , Humanos , Espectrometria de Massa com Troca Hidrogênio-Deutério , Ácido Láctico/metabolismo , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Compostos Organometálicos , Reação em Cadeia da Polimerase em Tempo Real
15.
Lab Invest ; 101(8): 1071-1083, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33875793

RESUMO

A diabetic foot ulcer (DFU) is one of the most devastating complications of diabetes. It has been reported that lncRNA GAS5 plays a vital role in wound healing in DFUs. However, the specific mechanism remains unclear. In this research, we aimed to investigate the role of GAS5 in wound healing in DFUs as well as the underlying mechanism. qPCR or western blotting was performed to measure the expression levels of GAS5, HIF1A, VEGF and TAF15. CCK-8 or EdU assays, flow cytometry, wound healing assays and tube formation assays were carried out to assess the proliferation, apoptosis, wound healing and in vitro angiogenesis of HUVECs, respectively. RNA pull-down and RIP assays were performed to verify the interaction between GAS5 and TAF15. ChIP and luciferase assays were conducted to verify the binding of TAF15 to the HIF1A promoter. In the DFU mouse model, H&E and Masson staining were used to determine epidermal and dermal thickness and collagen formation. GAS5 and HIF1A were downregulated in the skin tissues of DFU patients, and GAS5 overexpression promoted cell proliferation, wound healing and tubule formation in HG-treated HUVECs. In addition, GAS5 facilitated HIF1A expression by interacting with TAF15. Rescue assays demonstrated that the suppression of HIF1A/VEGF pathway activation partially reversed the functional roles of GAS5 in HUVECs. Furthermore, GAS5 accelerated wound healing by activating the HIF1A/VEGF pathway in mice with DFUs. GAS5 activates the HIF1A/VEGF pathway by binding to TAF15, resulting in accelerated wound healing in DFUs. Our findings may provide a theoretical basis for the clinical treatment of DFUs.


Assuntos
Pé Diabético/metabolismo , RNA Longo não Codificante , Fatores Associados à Proteína de Ligação a TATA , Cicatrização/genética , Adulto , Idoso , Animais , Proliferação de Células/genética , Células Cultivadas , Modelos Animais de Doenças , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Transdução de Sinais/genética , Fatores Associados à Proteína de Ligação a TATA/genética , Fatores Associados à Proteína de Ligação a TATA/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
16.
Cytogenet Genome Res ; 161(3-4): 167-177, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33951625

RESUMO

The barrier-to-autointegration factor (BAF) is widely expressed in most human tissues and plays a critical role in chromatin organization, nuclear envelope assembly, gonadal development, and embryonic stem cell self-renewal. Complete loss of BAF has been shown to lead to embryonic lethality and gonadal defects. The BAF paralog, namely, barrier-to-autointegration factor 2 (BANF2), exhibits a testis-predominant expression pattern in both humans and mice. Unlike BAF, it may cause isolated male infertility. Therefore, we used the CRISPR/Cas9 system to generate Banf2-knockout mice to further study its function in spermatogenesis. Unexpectedly, knockout mice did not show any detectable abnormalities in histological structure of the testis, epididymis, ovary, and other tissues, and exhibited normal fertility, indicating that Banf2 is not essential for mouse spermatogenesis and fertility.


Assuntos
Fertilidade/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas Nucleares/genética , Espermatogênese/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Sistemas CRISPR-Cas , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Genes Essenciais , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Nucleares/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espermatozoides/metabolismo , Testículo/citologia , Testículo/metabolismo
17.
J Org Chem ; 86(3): 2582-2592, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33423501

RESUMO

A highly chemoselective [2+1] annulation of α-alkylidene pyrazolones with α-bromonitroalkenes has been achieved under mild conditions. α-Alkylidene pyrazolones were unprecedentedly used as a C1 synthon to participate in annulation reactions, providing access to diverse vinylcyclopropane-based pyrazolone products. In addition, a spectrum of pharmaceutically interesting pyrazole-fused pyranone oximes could be rapidly obtained through a [2+1] annulation/rearrangement sequential process. Computational studies disclosed the origin of the observed chemoselectivity of the [2+1] cycloaddition.

18.
Appl Microbiol Biotechnol ; 105(19): 7095-7113, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34499202

RESUMO

Increased understanding of the interactions between endophytic fungi and plants has led to the discovery of a new generation of chemical compounds and processes between endophytic fungi and plants. Due to the long-term co-evolution between fungal endophytes and host plants, endophytes have evolved special biotransformation abilities, which can have critical consequences on plant metabolic processes and their composition. Biotransformation or bioconversion can impact the synthesis and decomposition of hormones, sugars, amino acids, vitamins, lipids, proteins, and various secondary metabolites, including flavonoids, polysaccharides, and terpenes. Endophytic fungi produce enzymes and various bioactive secondary metabolites with industrial value and can degrade or sequester inorganic and organic small molecules and macromolecules (e.g., toxins, pollutants, heavy metals). These fungi also have the ability to cause highly selective catalytic conversion of high-value compounds in an environmentally friendly manner, which can be important for the production/innovation of bioactive molecules, food and nutrition, agriculture, and environment. This work mainly summarized recent research progress in this field, providing a reference for further research and application of fungal endophytes. KEY POINTS: •The industrial value of degradation of endophytes was summarized. • The commercial value for the pharmaceutical industry is reviewed.


Assuntos
Fungos , Biotransformação
19.
Opt Express ; 28(5): 6336-6349, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-32225884

RESUMO

High-quality micro/nanolens arrays (M/NLAs) are becoming irreplaceable components of various compact and miniaturized optical systems and functional devices. There is urgent requirement for a low-cost, high-efficiency, and high-precision technique to manufacture high-quality M/NLAs to meet their diverse and personalized applications. In this paper, we report the one-step maskless fabrication of M/NLAs via electrohydrodynamic jet (E-jet) printing. In order to get the best morphological parameters of M/NLAs, we adopted the stable cone-jet printing mode with optimized parameters instead of the micro dripping mode. The optical parameters of M/NLAs were analyzed and optimized, and they were influenced by the E-jet printing parameters, the wettability of the substrate, and the viscosity of the UV-curable adhesive. Thus, diverse and customized M/NLAs were obtained. Herein, we realized the fabrication of nanolens with a minimum diameter of 120 nm, and NLAs with different parameters were printed on a silicon substrate, a cantilever of atomic force microscopy probe, and single-layer graphene.

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