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1.
Se Pu ; 42(4): 311-326, 2024 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-38566420

RESUMO

Ion chromatography (IC) is a novel high performance liquid chromatographic technique that is suitable for the separation and analysis of ionic substances in different matrix samples. Since 1975, it has been widely used in many fields, such as the environment, energy, food, and medicine. IC compensates for the separation limitations of traditional gas chromatography and high performance liquid chromatography and can realize the qualitative analysis and quantitative detection of strongly polar components. This chromatographic technique features not only simple operations but also rapid analysis. The sensors used in IC are characterized by high sensitivity and selectivity, and the technique can simultaneously separate and determine multiple components. Several advances in IC instrumentation and chromatographic theories have been developed in recent years. IC can analyze various types of samples, including ions, sugars, amino acids, and organic acids (bases). Chinese herbal medicines are typically characterized by highly complex chemical compositions and may contain carbohydrates, proteins, alkaloids, and other active components. They also contain toxic residues such as sulfur dioxide, which may be produced during the processing of medicinal materials. Therefore, the analysis and elucidation of the precise chemical constituents of Chinese herbal medicines present key problems that must be resolved in modern Chinese herbal medicine research. In this context, IC has become an important method for analyzing and identifying the complex components of Chinese herbal medicines because this method is suitable for detecting a single active ingredients among complex components. This paper introduces the different types and principles of IC as well as research progress in this technique. As the applications of IC-based methods in pharmaceutical science, cell biology, and microbiology increase, further development is necessary to expand the applications of this technique. The development of innovative techniques has enabled IC technologies to achieve higher analytical sensitivity, better selectivity, and wider application. The components of Chinese herbal medicines can be divided into endogenous and exogenous components according to their source: endogenous components include glycosides, amino acids, and organic acids, while exogenous components include toxic residues such as sulfur dioxide. Next, the applications of IC to the complex components of Chinese herbal medicines in recent decades are summarized. The most commonly used IC technologies and methods include ion exchange chromatography and conductivity detection. The advantages of IC for the analysis of alkaloids have been demonstrated. This method exhibits better characteristics than traditional analytical methods. However, the applications of IC for the speciation analysis of inorganic anions are limited. Moreover, few reports on the direct application of the technique for the determination of the main active substances in Chinese herbal medicines, including flavonoids, phenylpropanoids, and steroids, have been reported. Finally, this paper reviews new IC technologies and their application progress in Chinese herbal medicine, focusing on their prospects for the effective separation and analysis of complex components. In particular, we discuss the available sample (on-line) pretreatment technologies and explore possible technologies for the selective and efficient enrichment and separation of different components. Next, we assess innovative research on solid-phase materials that can improve the separation effect and analytical sensitivity of IC. We also describe the features of multidimensional chromatography, which combines the advantages of various chromatographic techniques. This review provides a theoretical reference for the further development of IC technology for the analysis of the complex chemical components of Chinese herbal medicines.


Assuntos
Alcaloides , Medicamentos de Ervas Chinesas , Medicamentos de Ervas Chinesas/análise , Dióxido de Enxofre/análise , Alcaloides/análise , Cromatografia Líquida de Alta Pressão , Íons , Medicina Tradicional Chinesa
2.
Med Res Rev ; 44(3): 1013-1054, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38140851

RESUMO

The burgeoning prodrug strategy offers a promising avenue toward improving the efficacy and specificity of cytotoxic drugs. Elevated intracellular levels of glutathione (GSH) have been regarded as a hallmark of tumor cells and characteristic feature of the tumor microenvironment. Considering the pivotal involvement of elevated GSH in the tumorigenic process, a diverse repertoire of GSH-triggered prodrugs has been developed for cancer therapy, facilitating the attenuation of deleterious side effects associated with conventional chemotherapeutic agents and/or the attainment of more efficacious therapeutic outcomes. These prodrug formulations encompass a spectrum of architectures, spanning from small molecules to polymer-based and organic-inorganic nanomaterial constructs. Although the GSH-triggered prodrugs have been gaining increasing interests, a comprehensive review of the advancements made in the field is still lacking. To fill the existing lacuna, this review undertakes a retrospective analysis of noteworthy research endeavors, based on a categorization of these molecules by their diverse recognition units (i.e., disulfides, diselenides, Michael acceptors, and sulfonamides/sulfonates). This review also focuses on explaining the distinct benefits of employing various chemical architecture strategies in the design of these prodrug agents. Furthermore, we highlight the potential for synergistic functionality by incorporating multiple-targeting conjugates, theranostic entities, and combinational treatment modalities, all of which rely on the GSH-triggering. Overall, an extensive overview of the emerging field is presented in this review, highlighting the obstacles and opportunities that lie ahead. Our overarching goal is to furnish methodological guidance for the development of more efficacious GSH-triggered prodrugs in the future. By assessing the pros and cons of current GSH-triggered prodrugs, we expect that this review will be a handful reference for prodrug design, and would provide a guidance for improving the properties of prodrugs and discovering novel trigger scaffolds for constructing GSH-triggered prodrugs.


Assuntos
Antineoplásicos , Pró-Fármacos , Humanos , Pró-Fármacos/farmacologia , Pró-Fármacos/química , Estudos Retrospectivos , Antineoplásicos/farmacologia , Antineoplásicos/química , Glutationa/química , Linhagem Celular Tumoral
3.
Anal Chem ; 95(40): 14833-14841, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37747928

RESUMO

Carbonic anhydrases (CAs) participate in various physiological and pathological activities by catalyzing the interconversion between carbon dioxide and bicarbonate ions. Under normal circumstances, they guarantee that the relevant biological reactions in our body occur within an appropriate time scale. Abnormal expression or activity alteration of CAs is closely related to the pathogenesis of diverse diseases. This work reports an inhibitor-directed fluorescent probe FMRs-CA for the detection of CAs. Excellent selectivity, favorable biocompatibility, and desirable blood-brain barrier (BBB) penetration endow the probe with the ability to image the fluctuation of CAs in cells and mice. We achieved in situ visualization of the increased CAs in hypoxic cells with this probe. Additionally, probe FMRs-CA was mainly enriched within the liver and gradually metabolized by the liver. With the help of FMRs-CA, the increase of CAs in epileptic mouse brains was revealed first from the perspective of imaging, providing the mechanism connection between abnormal CA expressions and epilepsy.

4.
Chem Biodivers ; 20(7): e202300050, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37314937

RESUMO

BACKGROUND: Liver cancer is an extremely common cancer with the highest mortality rate and poor prognosis. Owing to their low systemic toxicity and few side effects, natural compounds may provide better therapeutic effects for patients. (2E)-1-(2,4,6-trimethoxyphenyl)-3-(4-chlorophenyl)prop-2-en-1-one (TMOCC), a chalcone derivative, exhibits cytotoxicity towards many tumor cells. However, the anticancer mechanism of TMOCC has not been elucidated in human hepatocellular carcinoma (HCC). METHODS: Cell Counting Kit-8 and colony formation assays were used to evaluate the effects of TMOCC on viability and proliferation. Mitochondrial transmembrane potential and flow cytometry assays were used to detect apoptosis. The expression levels of proteins related to apoptosis, the RAS-ERK and AKT/FOXO3a signaling pathways were assessed using western blot. Potential targets of TMOCC were detected using molecular docking analysis. RESULTS: TMOCC inhibited viability and proliferation, and induced the loss of mitochondrial transmembrane potential, apoptosis and DNA double-strand breaks in both HCC cells. The RAS-ERK and AKT/FOXO3a signaling pathways were suppressed by TMOCC. Finally, ERK1, PARP-1, and BAX were identified as potential targets of TMOCC. CONCLUSION: Taken together, our results show that TMOCC promotes apoptosis by suppressing the RAS-ERK and AKT/FOXO3a signaling pathways. TMOCC may be a potential multi-target compound that is effective against liver cancer.


Assuntos
Carcinoma Hepatocelular , Chalcona , Chalconas , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Chalconas/farmacologia , Chalconas/uso terapêutico , Chalcona/farmacologia , Simulação de Acoplamento Molecular , Apoptose , Linhagem Celular Tumoral , Proliferação de Células
5.
Bioorg Chem ; 138: 106589, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37320912

RESUMO

Inhibiting thioredoxin reductase (TrxR) to disrupt the redox equilibrium and induce tumor cell apoptosis is a significant tumor therapeutic strategy. Piperine, a natural product from black pepper, has been demonstrated to suppress tumor cell proliferation by enhancing reactive oxygen species (ROS), subsequently leading to cell death. However, the development of Piperine as an active molecule is hampered by its weak cytotoxicity. To develop a compound with higher activity, we synthesized 22 Piperine analogs and evaluated their pharmacological properties. Ultimately, B5 was screened by the results of cytotoxicity and inhibition of TrxR activity. In contrast to Piperine, B5 had significant cytotoxicity with a 4-fold increase. The structure-activity relationship demonstrated that the introduction of an electron-withdrawing group into the benzene ring adjacent to the amino group, particularly in the meta-position, was positive and that shortening the olefin double bond had no appreciable impact on cytotoxicity. Further investigating the physiological activity of B5 in HeLa cells, we found that B5 selectively inhibits the activity of TrxR by binding to Sec residues on TrxR. B5 then induces cellular oxidative stress and finally leads to apoptosis. As a result, the study of B5 paved the way for further investigation into the modification and function of Piperine analogs as TrxR inhibitors.


Assuntos
Neoplasias , Tiorredoxina Dissulfeto Redutase , Humanos , Células HeLa , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Apoptose
6.
Free Radic Biol Med ; 206: 13-21, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37364691

RESUMO

Aloe-emodin (AE), a novel ferroptosis inhibitor, alleviates the doxorubicin (DOX)-induced cardiotoxicity in H9c2 rat cardiomyocytes. The inhibition of ferroptosis and the protective effect against cardiotoxicity were evaluated via MTT assay in H9c2 cells. The molecular mechanism of action (MOA) of nuclear factor erythroid 2-related factor 2 (Nrf2) activation, including transactivation of multiple downstream cytoprotective genes, were further assessed by Western blot, luciferase reporter assay and qRT-PCR analyses. Fluorescent imaging was performed to detect the change of intracellular reactive oxygen species, mitochondrial membrane potential and lipid peroxidation. In addition, an infrared spectroscopy was employed to detect the AE-Fe (II) complex. AE, alleviates oxidative stress in DOX-induced H9c2 cells by activating Nrf2 and increasing the expression of Nrf2 downstream antioxidant genes, SLC7A11 and GPX4. Furthermore, AE complexes bivalent iron and regulates the intracellular iron-related genes. In conclusion, the discovery of AE as a novel ferroptosis inhibitor and its MOA provides a new perspective for further exploration of cardio-protective agents in cancer patients during chemotherapy.


Assuntos
Aloe , Emodina , Ferroptose , Ratos , Animais , Cardiotoxicidade/tratamento farmacológico , Emodina/metabolismo , Emodina/farmacologia , Emodina/uso terapêutico , Aloe/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Transdução de Sinais , Linhagem Celular , Doxorrubicina/farmacologia , Estresse Oxidativo , Miócitos Cardíacos/metabolismo
7.
Angew Chem Int Ed Engl ; 62(21): e202301598, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36939218

RESUMO

The development of small-molecule probes suitable for live-cell applications remains challenging yet highly desirable. We report the first fluorescent probe, RBH, for imaging the heme oxygenase-1 (HO-1) activity in live cells after discovering hemin as a universal dark quencher. Hemin works via a static quenching mechanism and shows high quenching efficiency (>97 %) with fluorophores across a broad spectrum (λex =400-700 nm). The favorable properties of RBH (e.g. long excitation/emission wavelengths, fast response rate and high magnitude of signal increase) enable its use for determining HO-1 activity in complex biological samples. As HO-1 is involved in regulating antioxidant defence, iron homeostasis and gasotransmitter carbon monoxide production, we expect RBH to be a powerful tool for dissecting its functions. Also, the discovery of hemin as a general static dark quencher provides a straightforward strategy for constructing novel fluorescent probes for diverse biological species.


Assuntos
Heme Oxigenase-1 , Hemina , Corantes Fluorescentes , Heme Oxigenase (Desciclizante) , Antioxidantes
8.
Anal Chem ; 95(9): 4301-4309, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36812128

RESUMO

Glutathione (GSH), the most prevalent nonprotein thiol in biological systems, acts as both an antioxidant to manipulate intracellular redox homeostasis and a nucleophile to detoxify xenobiotics. The fluctuation of GSH is closely related to the pathogenesis of diverse diseases. This work reports the construction of a nucleophilic aromatic substitution-type probe library based on the naphthalimide skeleton. After an initial evaluation, the compound R13 was identified as a highly efficient GSH fluorescent probe. Further studies demonstrate that R13 could readily quantify GSH in cells and tissues via a straightforward fluorometric assay with a comparable accuracy to the results from the HPLC. We then used R13 to quantify the content of GSH in mouse livers after X-ray irradiation, revealing that irradiation-induced oxidative stress leads to the increase of oxidized GSH (GSSG) and depletion of GSH. In addition, probe R13 was also applied to investigate the alteration of the GSH level in the Parkinson's mouse brains, showing a decrease of GSH and an increase of GSSG in Parkinson's mouse brains. The convenience of the probe in quantifying GSH in biological samples facilitates further understanding of the fluctuation of the GSH/GSSG ratio in diseases.


Assuntos
Naftalimidas , Doença de Parkinson , Camundongos , Animais , Dissulfeto de Glutationa/metabolismo , Glutationa/metabolismo , Oxirredução , Estresse Oxidativo , Esqueleto/metabolismo
9.
Free Radic Biol Med ; 195: 121-131, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36581057

RESUMO

Photodynamic therapy (PDT) is a non-invasive, light-activated treatment approach that has been broadly employed in cancer. Cyclometallic iridium (Ш) complexes are candidates for ideal photosensitizers due to their unique photophysical and photochemical features, such as high quantum yield, large Stokes shift, strong resistance to photobleaching, and high cellular permeability. We evaluated a panel of iridium complexes and identified PC9 as a powerful photosensitizer to kill cancer cells. PC9 shows an 8-fold increase of cytotoxicity to HeLa cells under light irradiation. Further investigation discloses that PC9 has a strong mitochondrial-targeting ability and can inhibit the antioxidant enzyme thioredoxin reductase, which contributes to improving PDT efficacy. Our data indicate that iridium complexes are efficient photosensitizers with distinct physicochemical properties and cellular actions, and deserve further development as promising agents for PDT.


Assuntos
Fotoquimioterapia , Fármacos Fotossensibilizantes , Humanos , Fármacos Fotossensibilizantes/química , Irídio/farmacologia , Irídio/química , Células HeLa , Mitocôndrias , Oxirredução
10.
Chemosphere ; 312(Pt 1): 137225, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36375605

RESUMO

Extracellular polymeric substances (EPS) are important shields for microalgae when confronting with external stresses. However, the underlying roles of EPS in the interactions between microplastics (MPs) and microalgae remain poorly understood. In this study, three sizes of polystyrene (PS) MPs (20 nm, 100 nm, and 1 µm) were chosen for evaluating the compositions of EPS, secreted by Microcystis aeruginosa during exposure. The results indicated that the EPS compositions were different when M. aeruginosa was exposed to PS MPs of different sizes. The presence of EPS is helpful for alleviating the adverse effects of PS MPs on M. aeruginosa cell growth, photosynthesis, and oxidative stress. With the exception of the shading effect, insufficient EPS cause direct adsorption of unstable 1 µm PS MPs to the algal surface, which could destroy the cell wall. In contrast, aromatic proteins and fulvic acids are representative EPS components stimulated by 100 nm PS MPs, contributing to the self-aggregation and encapsulation of algal cells and availability of nutrients for algal growth, respectively. High amounts of polysaccharides were secreted by M. aeruginosa along with humic acids during exposure to 20 nm PS MPs, both of which are crucial in the homo-aggregation of 20 nm PS MPs toward minimize its adverse effects on M. aeruginosa. Together, these findings revealed the differences in EPS under the stimulation of PS MPs of different sizes and clarified the roles of different EPS components in resisting the adverse effects of PS MPs on M. aeruginosa.


Assuntos
Microalgas , Microcystis , Poluentes Químicos da Água , Microplásticos/toxicidade , Microcystis/metabolismo , Poliestirenos/metabolismo , Matriz Extracelular de Substâncias Poliméricas , Plásticos/metabolismo , Microalgas/metabolismo , Poluentes Químicos da Água/metabolismo
11.
Front Immunol ; 13: 987937, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36311708

RESUMO

Backgrounds: As a systemic skeletal dysfunction, osteoporosis (OP) is characterized by low bone mass and bone microarchitectural damage. The global incidences of OP are high. Methods: Data were retrieved from databases like Gene Expression Omnibus (GEO), GeneCards, Search Tool for the Retrieval of Interacting Genes/Proteins (STRING), Gene Expression Profiling Interactive Analysis (GEPIA2), and other databases. R software (version 4.1.1) was used to identify differentially expressed genes (DEGs) and perform functional analysis. The Least Absolute Shrinkage and Selection Operator (LASSO) logistic regression and random forest algorithm were combined and used for screening diagnostic markers for OP. The diagnostic value was assessed by the receiver operating characteristic (ROC) curve. Molecular signature subtypes were identified using a consensus clustering approach, and prognostic analysis was performed. The level of immune cell infiltration was assessed by the Cell-type Identification by Estimating Relative Subsets of RNA Transcripts (CIBERSORT) algorithm. The hub gene was identified using the CytoHubba algorithm. Real-time fluorescence quantitative PCR (RT-qPCR) was performed on the plasma of osteoporosis patients and control samples. The interaction network was constructed between the hub genes and miRNAs, transcription factors, RNA binding proteins, and drugs. Results: A total of 40 DEGs, eight OP-related differential genes, six OP diagnostic marker genes, four OP key diagnostic marker genes, and ten hub genes (TNF, RARRES2, FLNA, STXBP2, EGR2, MAP4K2, NFKBIA, JUNB, SPI1, CTSD) were identified. RT-qPCR results revealed a total of eight genes had significant differential expression between osteoporosis patients and control samples. Enrichment analysis showed these genes were mainly related to MAPK signaling pathways, TNF signaling pathway, apoptosis, and Salmonella infection. RT-qPCR also revealed that the MAPK signaling pathway (p38, TRAF6) and NF-kappa B signaling pathway (c-FLIP, MIP1ß) were significantly different between osteoporosis patients and control samples. The analysis of immune cell infiltration revealed that monocytes, activated CD4 memory T cells, and memory and naïve B cells may be related to the occurrence and development of OP. Conclusions: We identified six novel OP diagnostic marker genes and ten OP-hub genes. These genes can be used to improve the prognostic of OP and to identify potential relationships between the immune microenvironment and OP. Our research will provide insights into the potential therapeutic targets and pathogenesis of osteoporosis.


Assuntos
MicroRNAs , Osteoporose , Humanos , Prognóstico , Mapas de Interação de Proteínas/genética , Perfilação da Expressão Gênica , MicroRNAs/genética , Osteoporose/diagnóstico , Osteoporose/genética , Osteoporose/metabolismo
12.
Science ; 377(6611): 1223-1227, 2022 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-36074860

RESUMO

Hydroformylation with unmodified cobalt carbonyl catalyst plays a crucial role in industrial production of surfactants and plasticizers. However, syngas pressures of 100 to 400 bar with reaction temperatures of 100° to 250°C are typically applied. We report here that unmodified cobalt carbonyl is a stable hydroformylation catalyst at 140°C under 30 bar of syngas. The activity was comparable to that of recently reported bisphosphine-coordinated cobalt(II) catalysts, which we could not reproduce under the reported conditions. Kinetic and in situ infrared spectroscopic studies confirmed the stability of the unmodified cobalt tetracarbonyl hydride [HCo(CO)4]. Branched internal olefins were converted to aldehydes with high regioselectivity under low syngas pressures without phosphorus ligands. Bisphosphines had a small promotional effect on the catalyst at phosphorus-to-cobalt loading ratios below 0.6.

13.
J Assist Reprod Genet ; 39(6): 1383-1392, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35499778

RESUMO

PURPOSE: Few options are available for preserving female fertility to postpone childbirth. Although egg freezing with successful thawing is now possible, women' attitudes towards its use or the circumstances under which this technique may be considered remain unclear. METHODS: This study is a cross-sectional online survey. From November 2020 to January 2021, 848 questionnaires were collected through the Questionnaire Star Network platform, and a total of 750 valid answers were obtained. RESULTS: For more than 40% of the interviewees, the level of knowledge about egg freezing was only 0-25%; 36.9% of the interviewees supported elective egg freezing, and the main factor affecting their approval was major; approximately 60% of interviewees believed that being married should not be a condition for freezing eggs; and 56.7% of the interviewees supported the establishment of an egg bank in China, and the main factor affecting their acceptance was the place of residence. CONCLUSION: College students generally have a high level of recognition regarding elective egg freezing and the establishment of an egg bank, but their level of knowledge about egg freezing is low. Relevant knowledge must be strengthened to help college students achieve a correct understanding of elective egg freezing and egg bank establishment and then guide college students in developing a scientific dialectical attitude towards this technology.


Assuntos
Preservação da Fertilidade , Estudos Transversais , Criopreservação , Feminino , Preservação da Fertilidade/métodos , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Oócitos , Estudantes , Inquéritos e Questionários
14.
Methods Enzymol ; 662: 259-273, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35101214

RESUMO

Selenium (Se) is an essential trace element for diverse cellular functions. The biological significance of Se is predominantly dependent on its incorporation into the selenocysteine (Sec) for synthesis of selenoproteins (SePs), such as thioredoxin reductase family enzymes and glutathione peroxidase family enzymes. In general, the hyperactivity of the selenol group in Sec confers the Sec residue critical for functions of SePs. The Sec is much less abundant than its sulfur analog cysteine (Cys), and it remains a high challenge to detect Sec, especially in complex biological samples. We recently reported a selective fluorescent probe Sel-green for selenols and summarized the principles for design of selenol (and thiophenol) probes. Sel-green discriminates selenols from other biological species, especially thiols, under physiological conditions, and has been applied to detect both endogenous and exogenous selenol species in live cells. In this chapter, we describe a protocol and guideline for the selective detection of Sec by applying the Sel-green. This protocol is also suitable for detection of other selenol species. This practical and convenient assay would assist scientists to better understand the pivotal roles of Sec as well as SePs.


Assuntos
Compostos de Selênio , Selênio , Corantes Fluorescentes/química , Compostos de Selênio/química , Selenocisteína/química , Selenocisteína/metabolismo , Selenoproteínas/metabolismo
15.
Front Microbiol ; 13: 836052, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35185853

RESUMO

In this study, we report the biodiversity and functional characteristics of microplastic-attached biofilms originating from two freshwater bacterial communities. Even though the microplastic-biofilm (MPB) diversities are mostly determined by original bacteria instead of microplastic types, the results from 16S rRNA amplicon sequencing still showed that the dynamic biofilm successions on different microplastics were highly dissimilar. Furthermore, the analysis of biomarkers indicated distinct bacterial species with significant dissimilarities between different MPBs, which further determined the associated functions. The co-occurrence networks showed distinct interconnective characteristics in different MPBs: The structure of MPB incubated in the lake water sample was more robust under environmental stresses, and bacteria in the tap water MPB interacted more cooperatively. Regarding this cooperative interaction, the analysis of functional prediction, in this study, also showed that more symbionts and parasites colonized on microplastics in the tap water than in the lake water. Moreover, it was suggested that MPBs were more easily formed in the tap water sample. The overall results revealed significant dissimilarities in bacterial diversity, succession, and associated functions between MPBs, in which bacterial species with specific functions should be taken seriously.

16.
Int J Biol Sci ; 18(2): 841-857, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35002529

RESUMO

CircRNAs have garnered significant interest in recent years due to their regulation in human tumorigenesis, yet, the function of most glioma-related circRNAs remains unclear. In this study, using RNA-Seq, we screened differentially regulated circRNAs in glioma, in comparison to non-tumor brain tissue. Loss- and gain-of-function strategies were used to assess the effect of circCDK14 on tumor progression both in vitro and in vivo. Luciferase reporter, RNA pull-down and fluorescence in situ hybridization assays were carried out to validate interactions between circCDK14 and miR-3938 as well as miR-3938 and PDGFRA. Transmission electron microscopic observation of mitochondria, iron and reactive oxygen species assays were employed for the detection of circCDK14 effect on glioma cells' sensitivity to erastin-induced ferroptosis (Fp). Our findings indicated that circCDK14 was overexpressed in glioma tissues and cell lines, and elevated levels of circCDK14 induced poor prognosis of glioma patients. CircCDK14 promotes the migration, invasion and proliferation of glioma cells in vitro as well as tumorigenesis in vivo. An evaluation of the underlying mechanism revealed that circCDK14 sponged miR-3938 to upregulate oncogenic gene PDGFRA expression. Moreover, we also found that circCDK14 reduced glioma cells' sensitivity to Fp by regulating PDGFRA expression. In conclusion, circCDK14 induces tumor in glioma and increases malignant tumor behavior via the miR-3938/PDGFRA axis. Hence, the miR-3938/PDGFRA axis may be an excellent candidate of anti-glioma therapy.


Assuntos
Quinases Ciclina-Dependentes/genética , Ferroptose/genética , Regulação Neoplásica da Expressão Gênica , Glioma/patologia , RNA Circular/genética , Animais , Carcinogênese/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Quinases Ciclina-Dependentes/metabolismo , Progressão da Doença , Feminino , Glioma/genética , Glioma/metabolismo , Humanos , Hibridização in Situ Fluorescente , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/metabolismo , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Insects ; 12(12)2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34940144

RESUMO

Chinese silkworm (Antheraea pernyi) eggs are used as factitious hosts of Anastatus fulloi, and refrigeration of these eggs is essential for large-scale rearing of A. fulloi. We studied the effects of cold storage of A. pernyi eggs on egg quality and the fitness of A. fulloi reared on the eggs. Four cold storage treatments and two cold storage periods were assessed. The 0-3 °C refrigerator treatment was unsuitable for long-term (>70 days) storage. Cold storage at -5 °C and -18 °C increased the loss rate of A. pernyi eggs, but there was no significant difference between the control and 0-3 °C water bath treatment. The parasitism rate of A. fulloi was reduced when A. pernyi eggs were refrigerated for 6 or 12 months. There were no obvious differences in eclosion rate and percentage of females between control and eggs subjected to 6-month storage in 0-3 °C, -5 °C, and -18 °C water bath treatments. However, the eclosion rate and percentage of females decreased sharply when the storage period was 12 months. The overall eclosion rate of A. fulloi was reduced at the prolonged refrigeration time. Cold storage reduced host egg quality and their fitness suitability for A. fulloi. To minimize losses in the large-scale rearing of A. fulloi, A. pernyi eggs should be refrigerated in a 0-3 °C or -5 °C water bath treatment, and the storage period should not exceed 6 months.

18.
J Agric Food Chem ; 69(45): 13557-13567, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34726896

RESUMO

Metabolic reprogramming is critical for tumorigenesis. Pyruvate kinase M2 (PKM2) is overexpressed in lung carcinoma cells and plays a critical role in the Warburg effect, making the enzyme a research hotspot for anticancer drug development. Cynaropicrin (CYN), a natural sesquiterpene lactone compound from artichoke, has received increasing consideration due to its consumable esteem and pharmacological properties. Our data reveal that CYN not only inhibited the purified PKM2 activity but also decreased the cellular PKM2 expression in A549 cells. The inhibition of PKM2 leads to the upregulation of p53 and the downregulation of the DNA repair enzyme poly (ADP-ribose) polymerase (PARP), and subsequently causes the cell cycle arrest. Additionally, CYN inhibits the interaction of PKM2 and Nrf2, resulting in the impairment of cellular antioxidant capacity, induction of oxidative stress, and mitochondrial damages. Overexpression of PKM2 attenuates the CYN-induced DNA damage, mitochondrial fission, and cell viability. Thus, targeting PKM2 provides an original mechanism for understanding the pharmacological impact of CYN and assists in the further development of CYN as an anticancer agent.


Assuntos
Piruvato Quinase , Sesquiterpenos , Células A549 , Apoptose , Pontos de Checagem do Ciclo Celular , Dano ao DNA , Humanos , Lactonas/farmacologia , Dinâmica Mitocondrial , Piruvato Quinase/genética , Sesquiterpenos/farmacologia
19.
Chem Commun (Camb) ; 57(97): 13158-13161, 2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34812446

RESUMO

A metal-free C(sp3)-H phosphorylation of saturated aza-heterocycles via the merger of organic photoredox and Brønsted acid catalyses was established under mild conditions. This protocol provided straightforward and economic access to a variety of valuable α-phosphoryl cyclic amines by using commercially available diarylphosphine oxide reagents. In addition, the D-A fluorescent molecule DCQ was used for the first time as a photocatalyst and exhibited an excellent photoredox catalytic efficiency in this transformation. A series of mechanistic experiments and DFT calculations demonstrated that this transformation underwent a sequential visible light photoredox catalytic oxidation/nucleophilic addition process.

20.
Insects ; 12(10)2021 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-34680641

RESUMO

Anastatus japonicus Ashmead is a widely used biological control agent against stink bugs that can be successfully reared using the large eggs of the Chinese silkworm. In this study, environmental factors responsible for the induction of diapause in A. japonicus were investigated on host eggs of the Chinese silkworm. A. japonicus exhibited a facultative, mature larval diapause within its host eggs. Second-third instar larva are the most sensitive stages to diapause stimuli. The accumulation of diapause stimuli during all the larval stages maximized the diapause response. A short photoperiod of 10L:14D and temperature of 17 °C led to the occurrence of the highest diapause response, while a long photoperiod (14L:10D) and low temperatures (11 and 14 °C) prevented the diapause. A specific exposure period was required to reach high diapause incidence. Diapausing mature larvae had a significantly higher survival rate after 180 days storage at 10 °C than that of nondiapausing mature larvae. Taken together, results suggest methods that could be exploited in the developmental regulation, field-release pretreatment technology, and long-term storage of A. japonicus.

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