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1.
Curr Microbiol ; 81(9): 292, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090417

RESUMO

The taxonomic relationship between Streptomyces violarus and Streptomyces violaceus was reevaluated using a polyphasic taxonomic approach in this work. Phylogenetic analysis based on 16S rRNA gene sequences indicated that Streptomyces violarus JCM 4534 T was closely related to Streptomyces arenae ISP 5293 T. However, phylogenetic analysis based on five house-keeping gene (atpD, gyrB, recA, rpoB and trpB) showed that the evolutionary neighbor of Streptomyces violarus JCM 4534 T was Streptomyces violaceus CGMCC 4.1456 T, suggesting that there was a close genetic relationship between these two strains. The average nucleotide identity and digital DNA-DNA hybridization values between them were 97.0 and 72.9%, respectively, greater than the 96.7 and 70% cut-off points recommended for delineating a Streptomyces species. This result indicated that they belonged to the same genomic species which was also verified by a comprehensive comparison of phenotypic and chemotaxonomic characteristics between Streptomyces violarus JCM 4534 T and Streptomyces violaceus CGMCC 4.1456 T. According to all these data and the rule of priority in nomenclature, it is proposed the Streptomyces violarus (Artamonova and Krassilnikov 1960) Pridham 1970 is a later heterotypic synonym of Streptomyces violaceus (Rossi Doria 1891) Waksman 1953. In addition, based on dDDH, Streptomyces violaceus and Streptomyces violarus are simultaneously designated as two different subspecies, i.e., Streptomyces violaceus subsp. violaceus and Streptomyces violaceus subsp. violarus.


Assuntos
DNA Bacteriano , Filogenia , RNA Ribossômico 16S , Streptomyces , Streptomyces/genética , Streptomyces/classificação , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Análise de Sequência de DNA , Hibridização de Ácido Nucleico , Proteínas de Bactérias/genética
2.
Sci Adv ; 10(29): eado9413, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39018393

RESUMO

Chemical ligation of peptides is increasingly used to generate proteins not readily accessible by recombinant approaches. However, a robust method to ligate "difficult" peptides remains to be developed. Here, we report an enhanced native chemical ligation strategy mediated by peptide conjugation in trifluoroacetic acid (TFA). The conjugation between a carboxyl-terminal peptide thiosalicylaldehyde thioester and a 1,3-dithiol-containing peptide in TFA proceeds rapidly to form a thioacetal-linked intermediate, which is readily converted into the desired native amide bond product through simple postligation treatment. The effectiveness and practicality of the method was demonstrated by the successful synthesis of several challenging proteins, including the SARS-CoV-2 transmembrane Envelope (E) protein and nanobodies. Because of the ability of TFA to dissolve virtually all peptides and prevent the formation of unreactive peptide structures, the method is expected to open new opportunities for synthesizing all families of proteins, particularly those with aggregable or colloidal peptide segments.


Assuntos
Peptídeos , Ácido Trifluoracético , Ácido Trifluoracético/química , Peptídeos/química , SARS-CoV-2/química , Anticorpos de Domínio Único/química , Humanos , COVID-19/virologia
3.
Cytokine ; 182: 156718, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39084067

RESUMO

OBJECTIVE: To investigate the levels of 12 kinds of cytokines in seminal plasma and their correlations with routine semen parameters. METHODS: The remaining seminal plasma samples of 134 patients undergoing routine semen examination were collected for detecting cytokines. The parameters for sperm concentration, percentage of progressively motile sperm (PR), and motility were analyzed by a computer-assisted sperm analysis (CASA) system. According to the results of sperm concentration, PR and motility, 134 patients were divided into the normal routine semen parameters group, oligoasthenospermia group and azoospermia group. The levels of 12 kinds of cytokines in seminal plasma, including interleukin (IL)-1ß, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12P70, IL-17, interferin (IFN)-α, IFN-γ, and tumor necrosis factor (TNF)-α, were detected by flow cytometry. Two seminal plasma samples were detected for 10 times, respectively, to calculate the coefficients of variation (CV) of each cytokine. The linear range of each cytokine was measured using the standard, and the correlation coefficient (r) was calculated. RESULTS: The r2 of 12 kinds of cytokines detected by flow cytometry were all greater than 0.99. The reproducibility of 2 seminal plasma samples showed that the CVs of all cytokines were lower than 15 % except for TNF-α in sample 1 (15.15 %). Seminal plasma IL-6 levels were negatively correlated with semen volume (P < 0.01). Seminal plasma IL-5 levels were positively correlated with sperm concentration (P < 0.01). Seminal plasma IL-8 levels were negatively correlated with sperm motility (P < 0.01). Seminal plasma IL-8, IL-17 and IL-12P70 levels were negatively correlated with sperm PR (P < 0.05). In addition to the significant negative correlation between IL-5 and IL-17 (P < 0.05), there was a significant positive correlation between the majority of other cytokines. The levels of seminal plasma IL-17 and IL-12P70 in the oligoasthenospermia group and IL-1ß and IL-12P70 in the azoospermia group were significantly higher than those in the normal routine semen parameters group (P ≤ 0.05), while the levels of IL-10 in the azoospermia group were significantly lower than that in the normal routine semen parameters group (P < 0.05). CONCLUSION: There are certain correlations between seminal plasma cytokines and routine semen parameters and strong correlations between different seminal plasma cytokines, suggesting that the imbalance between seminal plasma cytokines may affect sperm quality. However, it still needs to be further confirmed by large samples and multi-center clinical studies and related basic researches.

4.
Nat Protoc ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867073

RESUMO

Catalytic mechanism-based, light-activated traps have recently been developed to identify the substrates of cysteine or serine hydrolases. These traps are hydrolase mutants whose catalytic cysteine or serine are replaced with genetically encoded 2,3-diaminopropionic acid (DAP). DAP-containing hydrolases specifically capture the transient thioester- or ester-linked acyl-enzyme intermediates resulting from the first step of the proteolytic reaction as their stable amide analogs. The trapped substrate fragments allow the downstream identification of hydrolase substrates by mass spectrometry and immunoblotting. In this protocol, we provide a detailed step-by-step guide for substrate capture and identification of the peptidase domain of the large tegument protein deneddylase (UL36USP) from human herpesvirus 1, both in mammalian cell lysate and live mammalian cells. Four procedures are included: Procedure 1, DAP-mediated substrate trapping in mammalian cell lysate (~8 d); Procedure 2, DAP-mediated substrate trapping in adherent mammalian cells (~6 d); Procedure 3, DAP-mediated substrate trapping in suspension mammalian cells (~5 d); and Procedure 4, substrate identification and validation (~12-13 d). Basic skills to perform protein expression in bacteria or mammalian cells, affinity enrichment and proteomic analysis are required to implement the protocol. This protocol will be a practical guide for identifying substrates of serine or cysteine hydrolases either in a complex mixture, where genetic manipulation is challenging, or in live cells such as bacteria, yeasts and mammalian cells.

5.
Chem Rev ; 124(6): 3590-3607, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38478849

RESUMO

Carbon dioxide (CO2) has long been recognized as an ideal C1 feedstock comonomer for producing sustainable materials because it is renewable, abundant, and cost-effective. However, activating CO2 presents a significant challenge because it is highly oxidized and stable. A CO2/butadiene-derived δ-valerolactone (EVP), generated via palladium-catalyzed telomerization between CO2 and butadiene, has emerged as an attractive intermediate for producing sustainable copolymers from CO2 and butadiene. Owing to the presence of two active carbon-carbon double bonds and a lactone unit, EVP serves as a versatile intermediate for creating sustainable copolymers with a CO2 content of up to 29 wt % (33 mol %). In this Review, advances in the synthesis of copolymers from CO2 and butadiene with divergent structures through various polymerization protocols have been summarized. Achievements made in homo- and copolymerization of EVP or its derivatives are comprehensively reviewed, while the postmodification of the obtained copolymers to access new polymers are also discussed. Meanwhile, potential applications of the obtained copolymers are also discussed. The literature references were sorted into sections based on polymerization strategies and mechanisms, facilitating readers in gaining a comprehensive view of the present chemistry landscape and inspiring innovative approaches to synthesizing novel CO2-derived copolymers.

6.
J Agric Food Chem ; 72(22): 12516-12528, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38491972

RESUMO

Objectives: The aim of this study was to investigate the ameliorative effect of platycodin D (PD) on cognitive dysfunction in type 2 diabetes mellitus (T2DM) and its potential molecular mechanisms of action in vivo and in vitro. Materials and methods: An animal model of cognitive impairment in T2DM was established using a single intraperitoneal injection of streptozotocin (100 mg/kg) after 8 weeks of feeding a high-fat diet to C57BL/6 mice. In vitro, immunofluorescence staining and Western blot were employed to analyze the effects of PD on glucose-induced neurotoxicity in mouse hippocampal neuronal cells (HT22). Results: PD (2.5 mg/kg) treatment for 4 weeks significantly suppressed the rise in fasting blood glucose in T2DM mice, improved insulin secretion deficiency, and reversed abnormalities in serum triglyceride, cholesterol, low-density lipoprotein, and high-density lipoprotein levels. Meanwhile, PD ameliorated choline dysfunction in T2DM mice and inhibited the production of oxidative stress and apoptosis-related proteins of the caspase family. Notably, PD dose-dependently prevents the loss of mitochondrial membrane potential, promotes phosphorylation of phosphatidylinositol 3 kinase and protein kinase B (Akt) in vitro, activates glycogen synthase kinase 3ß (GSK3ß) expression at the Ser9 site, and inhibits Tau protein hyperphosphorylation. Conclusions: These findings clearly indicated that PD could alleviate the neurological damage caused by T2DM, and the phosphorylation of Akt at Ser473 may be the key to its effect.


Assuntos
Disfunção Cognitiva , Diabetes Mellitus Tipo 2 , Saponinas , Transdução de Sinais , Triterpenos , Animais , Humanos , Masculino , Camundongos , Glicemia/metabolismo , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Glicogênio Sintase Quinase 3 beta/genética , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Saponinas/farmacologia , Saponinas/administração & dosagem , Transdução de Sinais/efeitos dos fármacos , Triterpenos/farmacologia , Triterpenos/administração & dosagem
7.
ACS Macro Lett ; 13(3): 315-321, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38382063

RESUMO

Carbon dioxide (CO2), as a renewable and nontoxic C1 feedstock, has been recognized as an ideal comonomer to prepare sustainable materials. In this regard, substantial focus has been dedicated to the ring-opening copolymerization of CO2 and epoxides, which results in the creation of aliphatic polycarbonates in most cases. Here, we report an unprecedented strategy to synthesize functional and degradable polyester-co-polyethers from CO2, butadiene, and epoxides via a CO2/butadiene-derived δ-valerolactone intermediate (EVP). Utilizing a chromium salen complex as the catalyst, the copolymerization of EVP and epoxides was successfully achieved to produce CO2/butadiene/epoxide terpolymers. The obtained polyester-co-polyethers with varied 39-93 mol % EVP content (equal to 18-28 wt % CO2 incorporation) show high thermal stability, tunable glass-transition temperatures, on-demand functionality, and good chemical degradability. This method extends the potential to access functional CO2-based polymers.

8.
Front Biosci (Landmark Ed) ; 29(2): 73, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38420798

RESUMO

BACKGROUND: Triple-negative breast cancer (TNBC) is an aggressive form of breast cancer (BC), and it is often associated with a high tumor grade, a younger age at diagnosis, and a low survival rate. Conventional endocrine and anti-HER-2 therapies are usually ineffective against TNBC, creating treatment challenges and resulting in a poor prognosis. Hence, new targets and treatment strategies for TNBC are urgently required. METHODS: The GSE102818 dataset was used to identify differentially expressed genes (DEGs) between primary BC and metastatic BC lesions. The Cancer Genome Atlas and the cBioPortal platform were employed to explore mutations in candidate genes. Utilizing the Tumor IMmune Estimation Resource (TIMER), the relationship between the expression of candidate genes and immune cell infiltration was assessed. Additionally, the cell-specific expression of the candidate genes was examined in the immune microenvironment of primary BC and metastatic BC lesions using the single-cell RNA sequencing (scRNA-seq) datasets GSE118389 and GSE202695. Finally, the protein expression of the candidate genes in clinical TNBC samples was evaluated. RESULTS: CD8A was identified as a hub gene in the DEG network and was found to be down-regulated in metastatic BC lesions. CD8A expression was highly correlated with the infiltration of CD8+ T cells, and elevated CD8A expression was correlated with improved survival. Interestingly, scRNA-seq data revealed that CD8A was down-regulated in CD8+ T cells in the immune microenvironment of metastatic BC lesions. Finally, the evaluation of clinical samples confirmed the down-regulation of CD8A in the immune microenvironment of BC lung metastases. CONCLUSIONS: In patients with metastatic TNBC, high levels of CD8A (especially in the immune microenvironment) are associated with a good prognosis.


Assuntos
Neoplasias Pulmonares , Neoplasias de Mama Triplo Negativas , Humanos , Regulação para Baixo , Expressão Gênica , Oncogenes , Neoplasias de Mama Triplo Negativas/genética , Microambiente Tumoral/genética
9.
Mol Breed ; 44(2): 9, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38298744

RESUMO

With the increasing public attention to the health benefit of polyunsaturated fatty acids (PUFAs) and demand for linolenic acid (C18:3), it is of great significance to increase the C18:3 content in our meal. As an oil crop with high content of C18:3, Camelina sativa has three homologous copies of FAD2 and three homologous copies FAD3. In this study, we seed-specifically overexpressed two Camelina sativa fatty acid desaturase genes, CsFAD2 and CsFAD3, in rapeseed cultivar Zhongshuang 9. The results show that C18:3 content in CsFAD2 and CsFAD3 overexpressed seeds is increased from 8.62% in wild-type (WT) to 10.62-12.95% and 14.54-26.16%, respectively. We crossed CsFAD2 and CsFAD3 overexpression lines, and stable homozygous digenic crossed lines were obtained. The C18:3 content was increased from 8.62% in WT to 28.46-53.57% in crossed overexpression lines. In addition, we found that the overexpression of CsFAD2 and CsFAD3 had no effect on rapeseed growth, development, and other agronomic traits. In conclusion, we successfully generated rapeseed germplasms with high C18:3 content by simultaneously overexpressing CsFAD2 and CsFAD3, which provides a feasible way for breeding high C18:3 rapeseed cultivars. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-024-01445-0.

10.
Angew Chem Int Ed Engl ; 63(14): e202318897, 2024 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-38326236

RESUMO

Mirror-image proteins (D-proteins) are useful in biomedical research for purposes such as mirror-image screening for D-peptide drug discovery, but the chemical synthesis of many D-proteins is often low yielding due to the poor solubility or aggregation of their constituent peptide segments. Here, we report a Lys-C protease-cleavable solubilizing tag and its use to synthesize difficult-to-obtain D-proteins. Our tag is easily installed onto multiple amino acids such as DLys, DSer, DThr, and/or the N-terminal amino acid of hydrophobic D-peptides, is impervious to various reaction conditions, such as peptide synthesis, ligation, desulfurization, and transition metal-mediated deprotection, and yet can be completely removed by Lys-C protease under denaturing conditions to give the desired D-protein. The efficacy and practicality of the new method were exemplified in the synthesis of two challenging D-proteins: D-enantiomers of programmed cell death protein 1 IgV domain and SARS-CoV-2 envelope protein, in high yield. This work demonstrates that the enzymatic cleavage of solubilizing tags under denaturing conditions is feasible, thus paving the way for the production of more D-proteins.


Assuntos
Peptídeos , Proteínas , Proteínas/química , Peptídeos/química , Aminoácidos/química , Técnicas de Química Sintética/métodos , Peptídeo Hidrolases , Endopeptidases
11.
Cell Stress Chaperones ; 29(1): 10-20, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38219840

RESUMO

Glutamate is a neurotransmitter that can cause excitatory neurotoxicity when its extracellular concentration is too high, leading to disrupted calcium balance and increased production of reactive oxygen species (ROS). Cordycepin, a nucleoside adenosine derivative, has been shown to protect against excitatory neurotoxicity induced by glutamate. To investigate its potential neuroprotective effects, the present study employed fluorescence detection and spectrophotometry techniques to analyze primary hippocampal-cultured neurons. The results showed that glutamate toxicity reduced hippocampal neuron viability, increased ROS production, and increased intracellular calcium levels. Additionally, glutamate-induced cytotoxicity activated acetylcholinesterase and decreased glutathione levels. However, cordycepin inhibited glutamate-induced cell death, improved cell viability, reduced ROS production, and lowered Ca2+ levels. It also inhibited acetylcholinesterase activation and increased glutathione levels. This study suggests that cordycepin can protect against glutamate-induced neuronal injury in cell models, and this effect was inhibited by adenosine A1 receptor blockers, indicating that its neuroprotective effect is achieved through activation of the adenosine A1 receptor.


Assuntos
Fármacos Neuroprotetores , Fármacos Neuroprotetores/farmacologia , Ácido Glutâmico/toxicidade , Ácido Glutâmico/metabolismo , Acetilcolinesterase/metabolismo , Acetilcolinesterase/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Cálcio/metabolismo , Apoptose , Desoxiadenosinas/farmacologia , Desoxiadenosinas/metabolismo , Hipocampo/metabolismo , Neurônios/metabolismo , Glutationa/metabolismo
12.
Angew Chem Int Ed Engl ; 63(9): e202313640, 2024 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-38193587

RESUMO

D-peptide ligands can be screened for therapeutic potency and enzymatic stability using synthetic mirror-image proteins (D-proteins), but efficient acquisition of these D-proteins can be hampered by the need to accomplish their in vitro folding, which often requires the formation of correctly linked disulfide bonds. Here, we report the finding that temporary installation of natural O-linked-ß-N-acetyl-D-glucosamine (O-GlcNAc) groups onto selected D-serine or D-threonine residues of the synthetic disulfide-bonded D-proteins can facilitate their folding in vitro, and that the natural glycosyl groups can be completely removed from the folded D-proteins to afford the desired chirally inverted D-protein targets using naturally occurring O-GlcNAcase. This approach enabled the efficient chemical syntheses of several important but difficult-to-fold D-proteins incorporating disulfide bonds including the mirror-image tumor necrosis factor alpha (D-TNFα) homotrimer and the mirror-image receptor-binding domain of the Omicron spike protein (D-RBD). Our work establishes the use of O-GlcNAc to facilitate D-protein synthesis and folding and proves that D-proteins bearing O-GlcNAc can be good substrates for naturally occurring O-GlcNAcase.


Assuntos
Acetilglucosaminidase , Proteínas , Peptídeos , Polissacarídeos , Glucosamina
13.
Bioorg Chem ; 143: 107047, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38154387

RESUMO

Chemical protein synthesis offers a powerful way to access otherwise-difficult-to-obtain proteins such as mirror-image proteins. Although a large number of proteins have been chemically synthesized to date, the acquisition to proteins containing hydrophobic peptide fragments has proven challenging. Here, we describe an approach that combines the removable backbone modification strategy and the peptide hydrazide-based native chemical ligation for the chemical synthesis of a 28 kDa full-length PET degrading enzyme IGGC (a higher depolymerization efficiency of variant leaf-branch compost cutinase (LCC)) containing hydrophobic peptide segments. The synthetic ICCG exhibits the enzymatic activity and will be useful in establishing the corresponding mirror-image version of ICCG.


Assuntos
Polietilenotereftalatos , Hidrolases/química , Fragmentos de Peptídeos , Peptídeos/química , Polietilenotereftalatos/química
14.
Cancers (Basel) ; 15(20)2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37894336

RESUMO

Osteosarcoma (OS) is the most common primary bone malignancy that exhibits remarkable histologic diversity and genetic heterogeneity. The complex nature of osteosarcoma has confounded precise molecular categorization, prognosis, and prediction for this disease. In this study, we performed a comprehensive multiplatform analysis on 86 osteosarcoma tumors, including somatic copy-number alteration, gene expression and methylation, and identified three molecularly distinct and clinically relevant subtypes of osteosarcoma. The subgrouping criteria was validated on another cohort of osteosarcoma tumors. Previously unappreciated osteosarcoma-type-specific changes in specific genes' copy number, expression and methylation were revealed based on the subgrouping. The subgrouping and novel gene signatures provide insights into refining osteosarcoma therapy and relationships to other types of cancer.

15.
Cell Death Discov ; 9(1): 344, 2023 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-37717021

RESUMO

Wilson's disease (WD) is an inherited disease characterized by copper metabolism disorder caused by mutations in the adenosine triphosphatase copper transporting ß gene (ATP7B). Currently, WD cell and animal model targeting the most common R778L mutation in Asia is lacking. In addition, the mechanisms by which hepatocytes resist copper toxicity remain to be further elucidated. In this study, we aimed to construct a novel WD cell model with R778L mutation and dissected the molecular basics of copper resistance. A novel HepG2 cell line stably expressing the ATP7B R778L gene (R778L cell) was constructed. The expression of necroptosis- and autophagy-related molecules was detected by PCR and Western blot (WB) in wild-type (WT) HepG2 and R778L cells with or without CuSO4 treatment. In addition, we detected and compared the levels of autophagy and necroptosis in CuSO4-treated R778L cells with the activation and inhibition of autophagy. Moreover, the mRNA and protein levels of autophagy and necroptosis signaling molecules were compared in R778L cells with the overexpression and knockdown of Unc-51 Like Autophagy Activating Kinase 1 (ULK1) and Autophagy Related 16 Like 1 (ATG16L1). We successfully constructed an R778L mutation HepG2 cell line. CuSO4 triggered the enhanced expression of autophagy and necroptosis signaling molecules in WT HepG2 cells and R778L cells. Remarkably, higher levels of autophagy and necroptosis were observed in R778L cells compared with those in WT cells. Autophagy activation led to weakened necroptosis mediated by RIPK3 and MLKL, conversely, autophagy inhibition brought about enhanced necroptosis. At the molecular level, ULK1- and ATG16L1 overexpression resulted in reduced necroptosis levels and vice versa. ULK1- and ATG16L1-mediated autophagy activation protects hepatocytes against RIPK3- and MLKL-mediated necroptosis in our new WD cell model treated with CuSO4. Targeted therapy by autophagy activation or necroptosis inhibition may be a novel and effective strategy to treat WD.

16.
Biomed Pharmacother ; 165: 115163, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37453196

RESUMO

Cordycepin (with a molecular formula of C10H13N5O3), a natural adenosine isolated from Cordyceps militaris, has an important regulatory effect on skeletal muscle remodelling and quality maintenance. The aim of this study was to investigate the effect of cordycepin on myoblast differentiation and explore the underlying molecular mechanisms of this effect. Our results showed that cordycepin inhibited myogenesis by downregulating myogenic differentiation (MyoD) and myogenin (MyoG), preserved undifferentiated reserve cell pools by upregulating myogenic factor 5 (Myf5) and retinoblastoma-like protein p130 (p130), and enhanced energy reserves by decreasing intracellular reactive oxygen species (ROS) and enhancing mitochondrial membrane potential, mitochondrial mass, and ATP content. The effect of cordycepin on myogenesis was associated with increased phosphorylation of extracellular signal-regulated kinase 1/2 (p-ERK1/2). PD98059 (a specific inhibitor of p-ERK1/2) attenuated the inhibitory effect of cordycepin on C2C12 differentiation. The present study reveals that cordycepin inhibits myogenesis through ERK1/2 MAPK signalling activation accompanied by an increase in skeletal muscle energy reserves and improving skeletal muscle oxidative stress, which may have implications for its further application for the prevention and treatment of degenerative muscle diseases caused by the depletion of depleted muscle stem cells.


Assuntos
Desoxiadenosinas , Sistema de Sinalização das MAP Quinases , Diferenciação Celular , Desoxiadenosinas/farmacologia , Desenvolvimento Muscular
17.
Angew Chem Int Ed Engl ; 62(33): e202306270, 2023 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-37357888

RESUMO

Membrane-associated D-proteins are an important class of synthetic molecules needed for D-peptide drug discovery, but their chemical synthesis using canonical ligation methods such as native chemical ligation is often hampered by the poor solubility of their constituent peptide segments. Here, we describe a Backbone-Installed Split Intein-Assisted Ligation (BISIAL) method for the synthesis of these proteins, wherein the native L-forms of the N- and C-intein fragments of the unique consensus-fast (Cfa) (i.e. L-CfaN and L-CfaC ) are separately installed onto the two D-peptide segments to be ligated via a removable backbone modification. The ligation proceeds smoothly at micromolar (µM) concentrations under strongly chaotropic conditions (8.0 M urea), and the subsequent removal of the backbone modification groups affords the desired D-proteins without leaving any "ligation scar" on the products. The effectiveness and practicality of the BISIAL method are exemplified by the synthesis of the D-enantiomers of the extracellular domains of T cell immunoglobulin and ITIM domain (TIGIT) and tropomyosin receptor kinase C (TrkC). The BISIAL method further expands the chemical protein synthesis ligation toolkit and provides practical access to challenging D-protein targets.


Assuntos
Inteínas , Proteínas , Peptídeos/química , Processamento de Proteína
18.
J Nat Med ; 77(4): 721-734, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37353674

RESUMO

This study investigated the protective effect of lobetyolin (LBT), a Q-marker isolated from the roots of Platycodon grandiflorum (Radix Platycodi), against cisplatin-induced cytotoxicity in human embryonic kidney (HEK293) cells. Results showed that LBT at 20 µM significantly prevented cisplatin-induced cytotoxicity by improving the viability of HEK293 cells, decreasing levels of MDA, and decreasing GSH content triggered by cisplatin. It also suppressed reactive oxygen species (ROS) levels. Molecular docking analysis revealed a strong binding affinity between LBT and the NF-κB protein, with a docking fraction of - 6.5 kcal/mol. These results provide compelling evidence suggesting a potential link between the visualization analysis of LBT and its protective mechanism, specifically implicating the NF-κB signaling pathway. LBT also reduced the expression level of tumor necrosis factor-alpha (TNF-α), phosphorylation NF-κB and IκBα in HEK293 cells which were increased by cisplatin exposure, leading to inhibition of inflammation. Furthermore, western blotting showed that LBT antagonized the up-regulation of Bax, cleaved caspase 3, 8, and 9 expression and inhibited the MAPK signaling pathway by down-regulating phosphorylation JNK, ERK, and p38, partially ameliorating cisplatin-induced cytotoxicity in HEK293 cells. Therefore, these results indicate that LBT has potentially protected renal function by inhibiting inflammation and apoptosis.


Assuntos
Cisplatino , NF-kappa B , Humanos , Cisplatino/toxicidade , Células HEK293 , NF-kappa B/metabolismo , Simulação de Acoplamento Molecular , Fator de Necrose Tumoral alfa/metabolismo , Apoptose , Inflamação
19.
Eur J Pharmacol ; 952: 175824, 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37263403

RESUMO

Red ginseng is a classical processed product from Panax ginseng. C.A Meyer with many bioactive components formed through the Maillard reaction called Maillard reaction products. Maillard reaction refers to complex reversible reactions between amino acids or proteins and glycosides, which are used in food processing and storage, as well as in tobacco development, traditional Chinese medicine processing, and wine brewing. Arginyl-fructosyl-glucose (AFG) is a main non-saponin (ginsenoside) component produced in red ginseng processing, with high antioxidant, anti-apoptotic and neuroprotective efficiencies. However, its effects and mechanisms against oxidation stress in on the brain remain elusive. Therefore, this study aimed at exploring the therapeutic effect exerted by AFG on murine subacute brain aging induced by D-galactose (D-gal) and its potential molecular mechanism in the murine model, finding that AFG (40 and 80 mg/kg) significantly ameliorated D-gal-resulted changes in pathology. Besides, according to the transmission electron microscopy (TEM) and Western blot, AFG corrected the mitochondrial dysfunction resulted from ROS, thereby delaying the mice brain aging caused by D-gal.


Assuntos
Galactose , Panax , Camundongos , Animais , Espécies Reativas de Oxigênio/metabolismo , Galactose/farmacologia , Envelhecimento , Encéfalo/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Panax/química , Mitocôndrias/metabolismo
20.
Drug Des Devel Ther ; 17: 1313-1322, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37152102

RESUMO

Purpose: This study aimed to evaluate the efficacy and safety of remazolam compared with propofol in patients who underwent laryngeal mask airway (LMA) insertion without the use of muscle relaxant agents during hysteroscopic surgery. Patients and Methods: A total of 72 patients undergoing hysteroscopy with LMA insertion were assigned to two groups. The patients in the remazolam group received 0.3 µg/kg sufentanil, 0.3 mg/kg remazolam and 1.2 mg/kg remifentanil, whereas the patients in the propofol group received 0.3 µg/kg sufentanil, 2.0 mg/kg propofol and 1.2 mg/kg remifentanil for insertion of the LMA. The primary endpoint was the summed score of the insertion conditions. The secondary endpoints included hemodynamics, the duration of induction, the duration of insertion, tidal volume, plateau pressure and adverse events. Results: No difference was identified between the propofol group and remazolam group in the median summed score [18.0 (18.0, 18.0), 18.0 (17.0, 18.0), respectively, P > 0.05]. The induction duration was significantly longer (P < 0.05) in the remazolam group than propofol group. The cost of dopamine (P < 0.05) was significantly lower in the remazolam group compared with the patients in the propofol group, while the plateau pressure (P < 0.05) and the incidence of transient mild laryngospasm (P < 0.05) were significantly higher in the remazolam group. No differences were identified between the two groups in terms of heart rate, tidal volume, injection pain or hiccups (P > 0.05). Conclusion: Remazolam provided similar insertion conditions and better hemodynamic stability than propofol during LMA insertion without the use of muscle relaxant agents. However, a higher incidence of transient mild laryngospasm was found in the remazolam group, which should be considered.


Assuntos
Máscaras Laríngeas , Laringismo , Propofol , Feminino , Gravidez , Humanos , Propofol/efeitos adversos , Anestésicos Intravenosos/efeitos adversos , Máscaras Laríngeas/efeitos adversos , Remifentanil , Histeroscopia/efeitos adversos , Sufentanil , Laringismo/induzido quimicamente , Estudos de Viabilidade , Vasodilatadores , Músculos
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