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1.
J Chem Phys ; 160(11)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38501473

RESUMO

We establish a theoretical model to analyze the photoassociative spectroscopy of 85Rb 133Cs molecules in the (3)3Σ+ state. The vibrational energy, spin-spin coupling constant, and hyperfine interaction constant of the (3)3Σ+ state are determined based on nine observed vibrational levels. Consequently, the Rydberg-Klein-Rees potential energy curve of the (3)3Σ+ state is obtained and compared with the ab initial potential energy curve. Our model can be adopted to analyze the photoassociative spectroscopy of other heteronuclear alkali-metal diatomic molecules in the (3)3Σ+ state.

2.
Phytomedicine ; 123: 155160, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37984122

RESUMO

BACKGROUND: Hypericum perforatum L. (HPL) is a potential traditional Chinese medicine. It could promotes menopausal 'kidney-yin deficiency syndrome' that characterized by renal function decline. However, its potential pharmacological effect and mechanism remains unknown. OBJECTIVE: The aim of this study was to investigate whether HPL can improve menopausal renal function decline and to explore its mechanism of action. METHODS: The mainly ingredients of HPL were identified using UPLC-Q-TOF-MS/MS approach, and the potential therapeutic targets of HPL for renal function decline were chose via network pharmacology technique. The key therapeutic metabolites were selected through non-targeted metabolomic and chemometric methods. Then, the network were constructed and the key targets and metabolites were screened. At last, the validation experiments and mechanism exploring were adopted by using Immunofluorescence, enzyme-linked immunosorbent assay (ELISA), real-time PCR (RT-PCR), and western blotting assays. RESULTS: mainly ingredients of HPL were identified and determined 17 compounds and 29 targets were chose as mainly active compounds and potential therapeutic targets. Based on OVX induced renal decline rat model, after chemometric analysis, 59 endo-metabolites were selected as key therapeutic metabolites, and AGE-RAGE signal pathway in diabetes complications was enriched as the key pathway. By constructing a "disease-component-target" network, Hyperoside, Quercetrin, and quinic were selected as the key therapeutic compounds, and the AKT1 and NOS3 were selected as the key therapeutic targets. The results of ELISA, RT-PCR and western blot experiments indicated that HPL could rescue the abnormal expressions both of AKT1 and NOS3, as well as their related metabolites distortion. CONCLUSION: Our findings indicated that HPL regulated expression of AKT1 and NOS3 through modulating AGE-RAGE signaling pathway in OVX stimulated rats` renal dysfunction, implicating the potential values of HPL in menopause syndromes therapy.


Assuntos
Antineoplásicos , Medicamentos de Ervas Chinesas , Hypericum , Feminino , Humanos , Animais , Ratos , Espectrometria de Massas em Tandem , Metabolômica , Rim , Ovariectomia , Óleos de Plantas , Simulação de Acoplamento Molecular , Proteínas Proto-Oncogênicas c-akt , Óxido Nítrico Sintase Tipo III
3.
Dev Cell ; 58(20): 2163-2180.e9, 2023 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-37582367

RESUMO

Tooth enamel secreted by ameloblasts (AMs) is the hardest material in the human body, acting as a shield to protect the teeth. However, the enamel is gradually damaged or partially lost in over 90% of adults and cannot be regenerated due to a lack of ameloblasts in erupted teeth. Here, we use single-cell combinatorial indexing RNA sequencing (sci-RNA-seq) to establish a spatiotemporal single-cell census for the developing human tooth and identify regulatory mechanisms controlling the differentiation process of human ameloblasts. We identify key signaling pathways involved between the support cells and ameloblasts during fetal development and recapitulate those findings in human ameloblast in vitro differentiation from induced pluripotent stem cells (iPSCs). We furthermore develop a disease model of amelogenesis imperfecta in a three-dimensional (3D) organoid system and show AM maturation to mineralized structure in vivo. These studies pave the way for future regenerative dentistry.


Assuntos
Esmalte Dentário , Odontogênese , Dente , Humanos , Ameloblastos/metabolismo , Amelogênese/genética
4.
Chin Med ; 18(1): 103, 2023 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-37598173

RESUMO

BACKGROUND: Fushenmu (Pini Radix in Poria, FSM) is a folk parasitic herb that has been mainly used for palpitation and amnesiain in traditional Chinese medicine (TCM). Recently, as an individual herb or a component of formulations, Fushenmu exhibits therapeutic potential for the treatment of cardiac arrhythmias. Yet, how specific targets or pathways of Fushenmu inhibit arrhythmia has not yet been reported. METHODS: Here, based on clinical functional genomics, metabolomics and molecular biologic technologies, a network construction strategy was adopted to identify FSM therapeutic targets and biomarkers that might explore its functions. RESULTS: In this study, it was found that FSM recovered arrhythmia-associated heart failure in barium chloride (BaCl2) induced arrhythmic zebrafish embryos, as was evidenced by the shortened cardiac sinus venosus-bulbus arteriosus (SV-BA) distance, smaller cardiovascular bleeding areas, and reduced cardiomyocyte apoptosis. Moreover, analysis via ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC-QTOF-ESI-MS/MS) components identification and network pharmacology prediction showed that 11 main active components of FSM acted on 33 candidate therapeutic targets. Metabolomic analysis also suggested that FSM could rescue 242 abnormal metabolites from arrhythmic zebrafish embryos. Further analysis based on the combination of target prediction and metabolomic results illustrated that FSM down-regulated Ryanodine Receptor 2 (RyR2) expressions, inhibited adrenaline and 3',5'-Cyclic AMP (cAMP) levels in a dose-dependent manner, which was confirmed by metabolites quantification and quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) assay. CONCLUSION: In summary, this study revealed that FSM mitigated BaCl2 induced cardiac damage caused by arrhythmia by suppressing RyR2 expressions, decreasing adrenaline and cAMP through the adrenergic signalling pathway.

5.
Anal Biochem ; 674: 115184, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37285946

RESUMO

OBJECTIVE: To investigate the therapeutic effect and mechanism of the traditional Chinese medicine Saposhnikovia divaricata (Trucz.) Schischk in rats with complete Freund's adjuvant-induced rheumatoid arthritis (RA). METHODS: The chemical targets and RA targets of Saposhnikovia divaricata (Trucz.) Schischk were acquired by the network pharmacological method. The complete Freund's adjuvant-induced rat RA model was used to further explore the mechanism of Saposhnikovia divaricata (Trucz.) Schischk in improving RA. Pathological changes in the volume of toes, body weight and synovial tissues of joints as well as serum inflammatory factor levels before and after the intervention of Saposhnikovia divaricata (Trucz.) Schischk were investigated. The key metabolic pathways were screened by correlations between metabolites and key targets. Finally, a quantitative analysis of key targets and metabolites was experimentally validated. RESULTS: Saposhnikovia divaricata (Trucz.) Schischk administration increased body weight, mitigated foot swelling and downregulated inflammatory cytokine levels in model rats. The histopathology showed that treatment with Saposhnikovia divaricata (Trucz.) Schischk can induce inflammatory cell infiltration and synovial hyperplasia and obviously reduce cartilage injuries, thus improving arthritis symptoms in rats. According to the network pharmacology-metabonomics association analysis results, the purine metabolic signaling pathway might be the key pathway for RA intervention with Saposhnikovia divaricata (Trucz.) Schischk. Targeted metabonomics, Western blotting (WB) and reverse transcription-polymerase chain reaction (RT‒PCR) assays showed that the recombinant adenosine deaminase (ADA) mRNA expression level and metabolic level of inosine in Saposhnikovia divaricata (Trucz.) Schischk administration group were lower than those of the model group. This reflected that Saposhnikovia divaricata (Trucz.) Schischk could improve RA by downregulating ADA mRNA expression levels and the metabolic level of inosine in the purine signaling pathway. CONCLUSION: Based on the "component-disease-target" association analysis, this study concludes that Saposhnikovia divaricata (Trucz.) Schischk improves complete Freund's adjuvant-induced RA symptoms in rats mainly by downregulating ADA mRNA expression levels in the purine metabolic signaling pathway, mitigating foot swelling, improving the levels of serum inflammatory factors (IL-1ß, IL-6 and TNF-α), and decreasing the ADA protein expression level to intervene in purine metabolism.


Assuntos
Apiaceae , Artrite Experimental , Artrite Reumatoide , Ratos , Animais , Adjuvante de Freund/efeitos adversos , Artrite Reumatoide/metabolismo , Inflamação/tratamento farmacológico , RNA Mensageiro , Artrite Experimental/tratamento farmacológico , Artrite Experimental/induzido quimicamente
6.
Science ; 380(6642): 266-273, 2023 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-37079676

RESUMO

As a result of evolutionary selection, the subunits of naturally occurring protein assemblies often fit together with substantial shape complementarity to generate architectures optimal for function in a manner not achievable by current design approaches. We describe a "top-down" reinforcement learning-based design approach that solves this problem using Monte Carlo tree search to sample protein conformers in the context of an overall architecture and specified functional constraints. Cryo-electron microscopy structures of the designed disk-shaped nanopores and ultracompact icosahedra are very close to the computational models. The icosohedra enable very-high-density display of immunogens and signaling molecules, which potentiates vaccine response and angiogenesis induction. Our approach enables the top-down design of complex protein nanomaterials with desired system properties and demonstrates the power of reinforcement learning in protein design.


Assuntos
Aprendizado de Máquina , Nanoestruturas , Engenharia de Proteínas , Proteínas , Microscopia Crioeletrônica , Proteínas/química
7.
Yi Chuan ; 45(2): 156-164, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36927662

RESUMO

DELLA gene family is involved in the regulation of signal transduction of plant hormones. mRNAs of GA insensitive (GAI), the member of DELLA gene family, are also signaling molecules of long-distance transport in plants. Genome-wide identification and mRNA transport analysis of the members of DELLA gene family in head cabbage (Brassica oleracea var. capitata) can provide basic data for their application in head cabbage. In this study, five members of DELLA gene family (BoRGA1, BoRGA2, BoRGL1, BoRGL2, and BoRGL3) were identified in head cabbage using genome and transcriptome data. However, head cabbage lacked a GAI gene in its genome. The scion (head cabbage, inbred line G27) and the rootstock Chinese flowering cabbage (Brassica campestris L. ssp. chinensis var. utilis Tsen et Lee) (sijiucaixin) were cleft-grafted together to produce the heterograft. Inflorescence stem of the rootstock and the corresponding inflorescence stem in Chinese flowering cabbage seedlings (as controls) were purified and analyzed with transcriptome sequencing. The total of 8, 9, 3, 5, and 1 exogenous read(s), derived respectively from BoRGA1, BoRGA2, BoRGL1, BoRGL2, and BoRGL3, were identified in the transcriptomes of the rootstocks. Nevertheless, mRNA transport of DELLA family genes from scion to rootstock did not increase the transcriptional level of the members of DELLA gene family in the rootstocks. Correlation analysis suggested that mRNA transport efficiency of the DELLA family genes was correlated with the sequence and the transcriptional level of the respective DELLA gene in the scion (head cabbage). This study lays the foundation for further investigation on the molecular mechanism of mRNA transport of the members of DELLA gene family in head cabbage.


Assuntos
Brassica , Brassica/genética , Xenoenxertos , Transcriptoma , Reguladores de Crescimento de Plantas , RNA Mensageiro/genética , Regulação da Expressão Gênica de Plantas
8.
Zhongguo Zhong Yao Za Zhi ; 48(2): 366-373, 2023 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-36725226

RESUMO

An analytical method for 10 mycotoxins in Hippophae Fructus medicinal and edible products was established in this study, and the contamination of their mycotoxins was analyzed. First of all, the mixed reference solution of ten mycotoxins such as aflatoxin, ochratoxin, zearalenone, and dexoynivalenol was selected as the control, and the Hippophae Fructus medicinal and edible products were prepared. Secondly, based on the ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) technology, 10 mycotoxins in Hippophae Fructus medicinal and edible products were quantitatively investigated and their content was determined. Finally, the contamination of mycotoxins was analyzed and evaluated. The optimal analysis conditions were determined, and the methodological inspection results showed that the 10 mycotoxins established a good linear relationship(r>0.99). The method had good repeatability, test sample specificity, stability, and instrument precision. The average recovery rates of 10 mycotoxins in Hippophae Fructus medicinal products, edible solids, and edible liquids were 90.31%-109.4%, 87.86%-107.8%, and 85.61%-109.1%, respectively. Relative standard deviation(RSD) values were 0.22%-10%, 0.75%-13%, and 0.84%-8.5%, repsectively. Based on UPLC-MS/MS technology, the simultaneous determination method for the limits of 10 mycotoxins established in this study has fast detection speed, less matrix interference, high sensitivity, and accurate results, which is suitable for the limit examination of 10 mycoto-xins in Hippophae Fructus medicinal and edible products.


Assuntos
Hippophae , Micotoxinas , Micotoxinas/análise , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Limite de Detecção , Cromatografia Líquida de Alta Pressão/métodos
9.
Artigo em Inglês | MEDLINE | ID: mdl-38259324

RESUMO

Over 90% of the U.S. adult population suffers from tooth structure loss due to caries. Most of the mineralized tooth structure is composed of dentin, a material produced and mineralized by ectomesenchyme derived cells known as odontoblasts. Clinicians, scientists, and the general public share the desire to regenerate this missing tooth structure. To bioengineer missing dentin, increased understanding of human tooth development is required. Here we interrogate at the single cell level the signaling interactions that guide human odontoblast and ameloblast development and which determine incisor or molar tooth germ type identity. During human odontoblast development, computational analysis predicts that early FGF and BMP activation followed by later HH signaling is crucial. Application of this sci-RNA-seq analysis generates a differentiation protocol to produce mature hiPSC derived odontoblasts in vitro (iOB). Further, we elucidate the critical role of FGF signaling in odontoblast maturation and its biomineralization capacity using the de novo designed FGFR1/2c isoform specific minibinder scaffolded as a C6 oligomer that acts as a pathway agonist. We find that FGFR1c is upregulated in functional odontoblasts and specifically plays a crucial role in driving odontoblast maturity. Using computational tools, we show on a molecular level how human molar development is delayed compared to incisors. We reveal that enamel knot development is guided by FGF and WNT in incisors and BMP and ROBO in the molars, and that incisor and molar ameloblast development is guided by FGF, EGF and BMP signaling, with tooth type specific intensity of signaling interactions. Dental ectomesenchyme derived cells are the primary source of signaling ligands responsible for both enamel knot and ameloblast development.

10.
Artigo em Inglês | MEDLINE | ID: mdl-36540608

RESUMO

Multiple pathologies and non-pathological factors can disrupt the function of the non-regenerative human salivary gland including cancer and cancer therapeutics, autoimmune diseases, infections, pharmaceutical side effects, and traumatic injury. Despite the wide range of pathologies, no therapeutic or regenerative approaches exist to address salivary gland loss, likely due to significant gaps in our understanding of salivary gland development. Moreover, identifying the tissue of origin when diagnosing salivary carcinomas requires an understanding of human fetal development. Using computational tools, we identify developmental branchpoints, a novel stem cell-like population, and key signaling pathways in the human developing salivary glands by analyzing our human fetal single-cell sequencing data. Trajectory and transcriptional analysis suggest that the earliest progenitors yield excretory duct and myoepithelial cells and a transitional population that will yield later ductal cell types. Importantly, this single-cell analysis revealed a previously undescribed population of stem cell-like cells that are derived from SD and expresses high levels of genes associated with stem cell-like function. We have observed these rare cells, not in a single niche location but dispersed within the developing duct at later developmental stages. Our studies introduce new human-specific developmental paradigms for the salivary gland and lay the groundwork for the development of translational human therapeutics.

11.
Int J Public Health ; 67: 1604654, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35496941

RESUMO

Objectives: To examine the association between smoking cessation and risk of type 2 diabetes with emphasis on post-cessation weight gain. Methods: In total, 8,951 participants from the China Health and Retirement Longitudinal Study at the baseline (2011) were included. Diabetes incidence was accessed at the third survey (2015). Current smokers were treated as the reference and odds ratios (OR) of type 2 diabetes for never smokers, recent, and long-term quitters were computed using multivariable logistic regression. Stratified analysis was further conducted by weight gain after smoking cessation. Results: There were 712 cases of type 2 diabetes identified. Compared with current smokers, the fully multivariable-adjusted ORs were 1.55 (1.02, 2.36) for recent quitters, 0.88 (0.61, 1.28) for long-term quitters, and 0.75 (0.59, 0.95) for never smokers. Stratified analysis showed recent quitters with weight gain of ≥2.0 kg had a significantly higher odds of type 2 diabetes [2.25 (1.02, 4.95)]. Conclusion: The present study of the Chinese population suggested recent quitters with weight gain of ≥2.0 kg, compared with current smokers, had a significantly increased odds of type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Abandono do Hábito de Fumar , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/etiologia , Humanos , Estudos Longitudinais , Estudos Prospectivos , Fumar/efeitos adversos , Fumar/epidemiologia , Aumento de Peso
12.
J Mol Cell Cardiol ; 167: 118-128, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35413295

RESUMO

Ryanodine receptor 2 (RyR2) is an ion channel in the heart responsible for releasing into the cytosol most of the Ca2+ required for contraction. Proper regulation of RyR2 is critical, as highlighted by the association between channel dysfunction and cardiac arrhythmia. Lower RyR2 expression is also observed in some forms of heart disease; however, there is limited information on the impact of this change on excitation-contraction (e-c) coupling, Ca2+-dependent arrhythmias, and cardiac performance. We used a constitutive knock-out of RyR2 in rabbits (RyR2-KO) to assess the extent to which a stable decrease in RyR2 expression modulates Ca2+ handling in the heart. We found that homozygous knock-out of RyR2 in rabbits is embryonic lethal. Remarkably, heterozygotes (KO+/-) show ~50% loss of RyR2 protein without developing an overt phenotype at the intact animal and whole heart levels. Instead, we found that KO+/- myocytes show (1) remodeling of RyR2 clusters, favoring smaller groups in which channels are more densely arranged; (2) lower Ca2+ spark frequency and amplitude; (3) slower rate of Ca2+ release and mild but significant desynchronization of the Ca2+ transient; and (4) a significant decrease in the basal phosphorylation of S2031, likely due to increased association between RyR2 and PP2A. Our data show that RyR2 deficiency, although remarkable at the molecular and subcellular level, has only a modest impact on global Ca2+ release and is fully compensated at the whole-heart level. This highlights the redundancy of RyR2 protein expression and the plasticity of the e-c coupling apparatus.


Assuntos
Adrenérgicos , Canal de Liberação de Cálcio do Receptor de Rianodina , Animais , Arritmias Cardíacas/metabolismo , Cálcio/metabolismo , Sinalização do Cálcio , Acoplamento Excitação-Contração , Miócitos Cardíacos/metabolismo , Coelhos , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Retículo Sarcoplasmático/metabolismo
13.
Sci Transl Med ; 14(646): eabn1252, 2022 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-35412328

RESUMO

New variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continue to arise and prolong the coronavirus disease 2019 (COVID-19) pandemic. Here, we used a cell-free expression workflow to rapidly screen and optimize constructs containing multiple computationally designed miniprotein inhibitors of SARS-CoV-2. We found the broadest efficacy was achieved with a homotrimeric version of the 75-residue angiotensin-converting enzyme 2 (ACE2) mimic AHB2 (TRI2-2) designed to geometrically match the trimeric spike architecture. Consistent with the design model, in the cryo-electron microscopy structure TRI2-2 forms a tripod at the apex of the spike protein that engaged all three receptor binding domains simultaneously. TRI2-2 neutralized Omicron (B.1.1.529), Delta (B.1.617.2), and all other variants tested with greater potency than the monoclonal antibodies used clinically for the treatment of COVID-19. TRI2-2 also conferred prophylactic and therapeutic protection against SARS-CoV-2 challenge when administered intranasally in mice. Designed miniprotein receptor mimics geometrically arrayed to match pathogen receptor binding sites could be a widely applicable antiviral therapeutic strategy with advantages over antibodies in greater resistance to viral escape and antigenic drift, and advantages over native receptor traps in lower chances of autoimmune responses.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , Microscopia Crioeletrônica , Humanos , Camundongos , Glicoproteína da Espícula de Coronavírus
15.
JCI Insight ; 6(24)2021 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-34767537

RESUMO

Kidneys are critical target organs of COVID-19, but susceptibility and responses to infection remain poorly understood. Here, we combine SARS-CoV-2 variants with genome-edited kidney organoids and clinical data to investigate tropism, mechanism, and therapeutics. SARS-CoV-2 specifically infects organoid proximal tubules among diverse cell types. Infections produce replicating virus, apoptosis, and disrupted cell morphology, features of which are revealed in the context of polycystic kidney disease. Cross-validation of gene expression patterns in organoids reflects proteomic signatures of COVID-19 in the urine of critically ill patients indicating interferon pathway upregulation. SARS-CoV-2 viral variants alpha, beta, gamma, kappa, and delta exhibit comparable levels of infection in organoids. Infection is ameliorated in ACE2-/- organoids and blocked via treatment with de novo-designed spike binder peptides. Collectively, these studies clarify the impact of kidney infection in COVID-19 as reflected in organoids and clinical populations, enabling assessment of viral fitness and emerging therapies.


Assuntos
Injúria Renal Aguda/urina , COVID-19/urina , Túbulos Renais Proximais/virologia , Rim/virologia , Organoides/virologia , SARS-CoV-2/patogenicidade , Injúria Renal Aguda/etiologia , Adulto , Idoso , Enzima de Conversão de Angiotensina 2/genética , Animais , Apoptose , Cápsula Glomerular/citologia , Cápsula Glomerular/virologia , COVID-19/complicações , Chlorocebus aethiops , Feminino , Técnicas de Inativação de Genes , Mortalidade Hospitalar , Hospitalização , Humanos , Rim/metabolismo , Rim/patologia , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/patologia , Masculino , Pessoa de Meia-Idade , Organoides/metabolismo , Podócitos/virologia , Doenças Renais Policísticas , Proteína Quinase D2/genética , Proteoma , Receptores de Coronavírus/genética , Reprodutibilidade dos Testes , Transcriptoma , Células Vero , Tropismo Viral , Replicação Viral
16.
EMBO Rep ; 22(12): e53471, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-34698433

RESUMO

Angiopoietins 1 and 2 (Ang1 and Ang2) regulate angiogenesis through their similar F-domains by activating Tie2 receptors on endothelial cells. Despite the similarity in the underlying receptor-binding interaction, the two angiopoietins have opposite effects: Ang1 induces phosphorylation of AKT, strengthens cell-cell junctions, and enhances endothelial cell survival while Ang2 can antagonize these effects, depending on cellular context. To investigate the molecular basis for the opposing effects, we examined the phenotypes of a series of computationally designed protein scaffolds presenting the Ang1 F-domain in a wide range of valencies and geometries. We find two broad phenotypic classes distinguished by the number of presented F-domains: Scaffolds presenting 3 or 4 F-domains have Ang2-like activity, upregulating pFAK and pERK but not pAKT, while scaffolds presenting 6, 8, 12, 30, or 60 F-domains have Ang1-like activity, upregulating pAKT and inducing migration and vascular stability. The scaffolds with 6 or more F-domains display super-agonist activity, producing stronger phenotypes at lower concentrations than Ang1. Tie2 super-agonist nanoparticles reduced blood extravasation and improved blood-brain barrier integrity four days after a controlled cortical impact injury.


Assuntos
Angiopoietinas , Células Endoteliais , Células Endoteliais/metabolismo , Neovascularização Fisiológica , Receptor TIE-2/genética , Receptor TIE-2/metabolismo , Transdução de Sinais
17.
Nat Commun ; 12(1): 6167, 2021 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-34697315

RESUMO

Human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) allow investigations in a human cardiac model system, but disorganized mechanics and immaturity of hPSC-CMs on standard two-dimensional surfaces have been hurdles. Here, we developed a platform of micron-scale cardiac muscle bundles to control biomechanics in arrays of thousands of purified, independently contracting cardiac muscle strips on two-dimensional elastomer substrates with far greater throughput than single cell methods. By defining geometry and workload in this reductionist platform, we show that myofibrillar alignment and auxotonic contractions at physiologic workload drive maturation of contractile function, calcium handling, and electrophysiology. Using transcriptomics, reporter hPSC-CMs, and quantitative immunofluorescence, these cardiac muscle bundles can be used to parse orthogonal cues in early development, including contractile force, calcium load, and metabolic signals. Additionally, the resultant organized biomechanics facilitates automated extraction of contractile kinetics from brightfield microscopy imaging, increasing the accessibility, reproducibility, and throughput of pharmacologic testing and cardiomyopathy disease modeling.


Assuntos
Coração/crescimento & desenvolvimento , Miocárdio , Miócitos Cardíacos/citologia , Células-Tronco Pluripotentes/citologia , Fenômenos Biomecânicos , Cálcio/metabolismo , Técnicas de Cultura de Células , Dimetilpolisiloxanos , Fenômenos Eletrofisiológicos , Perfilação da Expressão Gênica , Ensaios de Triagem em Larga Escala/instrumentação , Humanos , Dispositivos Lab-On-A-Chip , Modelos Cardiovasculares , Contração Miocárdica , Miocárdio/citologia , Miocárdio/metabolismo , Miofibrilas/metabolismo , Reprodutibilidade dos Testes
18.
Front Pharmacol ; 12: 688746, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34393777

RESUMO

The traditional Chinese medicine Poria cum Radix Pini (PRP) is a fungal medicinal material that has been proven to play an important role in the treatment of arrhythmia. However, the mechanism of its effect on arrhythmia is still unclear. In this study, network pharmacology and metabolomics correlation analysis methods were used to determine the key targets, metabolites and potential pathways involved in the effects of PRP on arrhythmia. The results showed that PRP can significantly improve cardiac congestion, shorten the SV-BA interval and reduce the apoptosis of myocardial cells induced by barium chloride in zebrafish. By upregulating the expression of the ADORA1 protein and the levels of adenosine and cGMP metabolites in the cGMP-PKG signalling pathway, PRP can participate in ameliorating arrhythmia. Therefore, we believe that PRP shows great potential for the treatment of arrhythmia.

19.
Geroscience ; 43(5): 2595-2609, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34297314

RESUMO

As the molecular mechanisms of biological aging become better understood, there is growing interest in identifying interventions that target those mechanisms to promote extended health and longevity. The budding yeast Saccharomyces cerevisiae has served as a premier model organism for identifying genetic and molecular factors that modulate cellular aging and is a powerful system in which to evaluate candidate longevity interventions. Here we screened a collection of natural products and natural product mixtures for effects on the growth rate, mTOR-mediated growth inhibition, and replicative lifespan. No mTOR inhibitory activity was detected, but several of the treatments affected growth rate and lifespan. The strongest lifespan shortening effects were observed for green tea extract and berberine. The most robust lifespan extension was detected from an extract of Pterocarpus marsupium and another mixture containing Pterocarpus marsupium extract. These findings illustrate the utility of the yeast system for longevity intervention discovery and identify Pterocarpus marsupium extract as a potentially fruitful longevity intervention for testing in higher eukaryotes.


Assuntos
Pterocarpus , Saccharomycetales , Longevidade , Extratos Vegetais/farmacologia , Saccharomyces cerevisiae
20.
bioRxiv ; 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34268509

RESUMO

Escape variants of SARS-CoV-2 are threatening to prolong the COVID-19 pandemic. To address this challenge, we developed multivalent protein-based minibinders as potential prophylactic and therapeutic agents. Homotrimers of single minibinders and fusions of three distinct minibinders were designed to geometrically match the SARS-CoV-2 spike (S) trimer architecture and were optimized by cell-free expression and found to exhibit virtually no measurable dissociation upon binding. Cryo-electron microscopy (cryoEM) showed that these trivalent minibinders engage all three receptor binding domains on a single S trimer. The top candidates neutralize SARS-CoV-2 variants of concern with IC 50 values in the low pM range, resist viral escape, and provide protection in highly vulnerable human ACE2-expressing transgenic mice, both prophylactically and therapeutically. Our integrated workflow promises to accelerate the design of mutationally resilient therapeutics for pandemic preparedness. ONE-SENTENCE SUMMARY: We designed, developed, and characterized potent, trivalent miniprotein binders that provide prophylactic and therapeutic protection against emerging SARS-CoV-2 variants of concern.

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