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1.
Heliyon ; 9(8): e18776, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37560633

RESUMO

Recently GeSe has developed as a promising light harvesting material by enjoying to its optical and electrical features as well as earth-abundant and low-toxic constituent elements. Nevertheless, the power conversion efficiency of GeSe-based solar cells yet lags far behind the Shockley-Queisser limit. In this work, we systematically designed, simulated and analyzed the highly efficient GeSe thin-film solar cells by SCAPS-1D. The influence of thickness and defect density of light harvest material, GeSe/CdS interface defect density, electron transport layer (ETL), electrode work function and hole transport layer (HTL) on the device output are carefully analyzed. By optimizing the parameters (thickness, defect, concentration, work function, ETL and HTL), an impressive PCE of 17.98% is delivered along with Jsc of 37.11 mA/cm2, FF of 75.53%, Voc of 0.61 V. This work offers theoretical guidance for the design of highly efficient GeSe thin film solar cells.

2.
J Cancer Res Clin Oncol ; 149(10): 7895-7903, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36809501

RESUMO

BACKGROUND AND PURPOSE: Nucleic acid aptamers are a novel molecular recognition tool that is functionally similar to antibodies but superior to antibodies in terms of thermal stability, structural modification, preparation, and cost, and therefore hold great promise for molecular detection. However, due to the limitations of a single aptamer in molecular detection, the multiple aptamer combination for bioanalysis has received much attention. Here, we reviewed the progress of tumor precision detection based on the combination of multiple nucleic acid aptamers and optical methods and discussed its challenges and prospects. METHODS: The relevant literature in PubMed was collected and reviewed. RESULTS: The combination of two or more aptamers with modern nanomaterials and analytical methods allows the fabrication of various detection systems for the simultaneous detection of different structural domains of a substance and/or different substances, including soluble tumor markers, tumor cell surface and intracellular markers, circulating tumor cells, and other tumor-related biomolecules, which has great potential for application in efficient and precise tumor detection. CONCLUSION: The combination of multiple nucleic acid aptamers provides a new approach for the precise detection of tumors and will play an important role in precision medicine for tumors.


Assuntos
Aptâmeros de Nucleotídeos , Nanoestruturas , Células Neoplásicas Circulantes , Ácidos Nucleicos , Humanos , Ácidos Nucleicos/química , Biomarcadores Tumorais/metabolismo
3.
Front Chem ; 10: 922110, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35734442

RESUMO

Janus kinases (JAKs) play a key role in subtly regulating proliferation, apoptosis, and differentiation of cancer cells, and their inhibitors are actively sought as new drug leads. By developing JAKs based affinity ultrafiltration method coupled with LC/Q-TOF-MS in order to discover selective JAKs inhibitors from total quaternary alkaloids (QAs) from Zanthoxylum simulans, peak 19 (Berberine) and peak 21 (Chelerythrine) were revealed to exhibit notable selectivity on JAK1, JAK2, and JAK3 over Tyk2. In addition, Chelerythrine showed stronger inhibitory activity than the positive control (Cerdulatinib) on gastric cancer cells (AGS), while Berberine, with weaker inhibition. Chelerythrine and Berberine also showed obvious inhibition on human hepatocyte cells (LO2). Furthermore, molecular docking analysis revealed their discrepancies due to different interaction bonds and characteristic residues. Quaternary N was proposed as the functional group to enhance the selectivity of JAK1, and some specific moieties towards Asp1021, Leu855, and Leu828 were suggested to increase the selectivity for JAK1, JAK2, and JAK3, respectively. As the most potential inhibitor of JAKs from QAs, Chelerythrine exhibited distinct suppression of adhesion, migration, invasion, and stimulating apoptosis of AGS cells, which was consistent with the significant down-regulation of estrogen receptors (ER-α36, ER-α66, and ER-ß1) and Src expression. In conclusion, an efficient screening approach was developed to identify Berberine and Chelerythrine as potential selective candidates from Zanthoxylum simulans with significant anti-proliferative activity against gastric carcinoma. As we know, it was the first report to propose an estrogen signal pathway for Chelerythrine in anti-gastric cancer cells (AGS) study. The results supported Chelerythrine inhibitory effects on AGS by not only direct inhibiting JAKs but also down-regulating the estrogen pathway.

4.
Antioxidants (Basel) ; 11(4)2022 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-35453343

RESUMO

Azadirachta indica (A. indica) has been widely used due to its diverse pharmacological activities. However, there are currently few studies on its responsible antioxidant ingredients against superoxide dismutase (SOD) and xanthine oxidase (XOD). In this study, the antioxidant activities of A. indica were evaluated by a 2,2'-azinobis-(3-ethyl-benzthiazoline)-6-sulfonic acid) and ferric-ion-reducing antioxidant power method. Meanwhile, total polyphenol and flavonoid content were determined to reveal that they were the highest in ethyl acetate (EA) fraction. Next, compounds with the most antioxidant activity were screened out from EA fraction by bio-affinity ultrafiltration liquid chromatography-mass spectrometry (UF-LC-MS) with SOD and XOD. As a result, gallic acid, protocatechuic acid and (-)-epicatechin were identified as potential SOD ligands with relative binding affinity (RBA) values of 2.15, 1.78 and 1.61, respectively. Additionally, these three ligands could effectively interact with SOD in molecular docking with binding energies (BEs) ranging from -3.84 ± 0.37 to -5.04 ± 0.01 kcal/mol. In addition, carnosic acid exhibited a strong binding affinity to XOD with an RBA value of 2.05 and BE value of -8.24 ± 0.71 kcal/mol. In conclusion, these results indicated that A. indica might have good antioxidant activity and antigout potential, and the UF-LC-MS method is suitable and efficient for screening both SOD and XOD ligands from A. indica.

5.
Cancer Biother Radiopharm ; 37(9): 750-758, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32818382

RESUMO

Background: APOBEC1 complementation factor (A1CF) is a component of the apolipoprotein-B messenger RNA editing complex that participates in various cellular processes and acts as an oncogene in many cancers. In this study, it was aimed to investigate the roles of A1CF and its potential mechanism in endometrial cancer (EC). Materials and Methods: Gene expression prolife was downloaded from The Cancer Genome Atlas database. Then Kaplan-Meier and Cox regression analyses were conducted to assess the prognostic value of A1CF in EC. Cell Counting Kit-8, plate clone formation, and transwell assays were used to estimate the functions of A1CF on the proliferation, invasion, and migration of EC cell. The gene set enrichment analysis was used to analyze the pathway that is enriched by A1CF, whereas quantitative real-time polymerase chain reaction and Western blot analyses were utilized to detect the mRNA and protein expression involved. Results: It was detected that the upregulated A1CF was enriched in P53/P21 signaling pathway and tightly associated with patients' age, stage, and death. Besides, high A1CF expression led to a shorter overall survival of patients and predicted a poor prognosis in EC. The overexpression of A1CF promoted the proliferation, invasion, and migration of EC cells, whereas the depletion of A1CF suppressed these processes. Moreover, P21 and P53 were reduced whereas cyclin D1 and proliferating cell nuclear antigen were induced along with the increasing of A1CF. However, the effects of silencing A1CF on these protein expressions were on the contrary. Conclusion: A1CF was highly expressed and closely related to the prognosis and progression of EC through the regulation of P53/P21 signaling pathway, providing a possible new therapy target site for EC.


Assuntos
Neoplasias do Endométrio , Proteínas de Ligação a RNA , Proteína Supressora de Tumor p53 , Feminino , Humanos , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Neoplasias do Endométrio/genética , Regulação Neoplásica da Expressão Gênica , Edição de RNA , RNA Mensageiro/genética , Transdução de Sinais , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteínas de Ligação a RNA/genética
6.
Antioxidants (Basel) ; 10(10)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34679694

RESUMO

Warburgia ugandensis Sprague (WU) is a traditional medicinal plant used for the treatment of various diseases, including cancer, in Africa. This study aimed to evaluate the anti-non-small cell lung cancer (NSCLC) activities of WU against A549 cells and to reveal potential molecular mechanisms. The cytotoxicity of various WU extracts was evaluated with HeLa (cervical cancer), HepG2 (liver cancer), HT-29 (colorectal cancer), and A549 (non-small cell lung cancer) cells by means of Sulforhodamine B (SRB) assay. Therein, the dimethyl carbonate extract of WU (WUD) was tested with the most potent anti-proliferative activity against the four cancer cell lines, and its effects on cell viability, cell cycle progression, DNA damage, intracellular reactive oxygen species (ROS), and expression levels of G0/G1-related proteins in A549 cells were further examined. First, it was found that WUD inhibited the proliferation of A549 cells in a time- and dose-dependent manner. In addition, WUD induced G0/G1 phase arrest and modulated the expression of G0/G1 phase-associated proteins Cyclin D1, Cyclin E1, and P27 in A549 cells. Furthermore, WUD increased the protein abundance of P27 by inhibiting FOXO3A/SKP2 axis-mediated protein degradation and also significantly induced the γH2AX expression and intracellular ROS generation of A549 cells. It was also found that the inhibitory effect of WUD on the proliferation and G0/G1 cell cycle progression of A549 cells could be attenuated by NAC, a ROS scavenger. On the other hand, phytochemical analysis of WUD with UPLC-QTOF-MS/MS indicated 10 sesquiterpenoid compounds. In conclusion, WUD exhibited remarkable anti-proliferative effects on A549 cells by improving the intracellular ROS level and by subsequently modulating the cell proliferation and G0/G1 cell cycle progression of A549 cells. These findings proved the good therapeutic potential of WU for the treatment of NSCLC.

7.
Pharmaceuticals (Basel) ; 14(4)2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33915848

RESUMO

Previous reports have illustrated that the incidence and mortality of cancer are increasing year by year worldwide. In addition, the occurrence, development, recurrence and metastasis of cancer are closely related to inflammation, which is a kind of defensive response of human body to various stimuli. As an important medicinal plant in Africa, Warburgia ugandensis has been reported to have certain anti-inflammatory and anti-proliferative activities, but its specific components and mechanisms of action remain elusive. To tackle this challenge, affinity ultrafiltration with drug targets of interest coupled to high-performance liquid chromatography-mass spectrometry (AUF-HPLC-MS/MS) could be utilized to quickly screen out bioactive constituents as ligands against target enzymes from complex extracts of this plant. AUF-HPLC-MS/MS with four drug targets, i.e., cyclooxygenase-2 (COX-2), 5-lipoxygenase (5-LOX), topoisomerase I (Top I) and topoisomerase II (Top II) were used to rapidly screen and characterize the anti-inflammatory and anti-proliferative natural ligands from W. ugandensis, and the resulting potential active compounds as ligands with specific binding affinity to COX-2, 5-LOX, Top I and Top II, were isolated with modern separation and purification techniques and identified with spectroscopic method like NMR, and then their antiinflammatory and anti-proliferative activities were tested to verify the screening results from AUF-HPLC-MS/MS. Compounds 1 and 2, which screened out and identified from W. ugandensis showed remarkable binding affinity to COX-2, 5-LOX, Top I and Top II with AUF-HPLC-MS/MS. In addition, 1 new compound (compound 3), together with 5 known compounds were also isolated and identified from W. ugandensis. The structure of compound 3 was elucidated by extensive 1D, 2D NMR data and UPLC-QTOF-MS/MS. Furthermore, compounds 1 and 2 were further proved to possess both anti-inflammatory and anti-proliferative activities which are in good agreement with the screening results using AUF-HPLC-MS/MS. This work showcased an efficient method for quickly screening out bioactive components with anti-inflammatory and anti-proliferative activity from complex medicinal plant extracts using AUF-HPLC-MS/MS with target enzymes of interest, and also demonstrated that neolignanamides (compounds 1 and 2) from W. ugandensis would be the active components responsible for its anti-inflammatory and anti-proliferative activity with the potential to treat cancer and inflammation.

8.
Pharmaceuticals (Basel) ; 14(3)2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33804242

RESUMO

Ficus glumosa Delile (Moraceae), a reputed plant that is used in herbal medicine, is of high medicinal and nutritional value in local communities primarily ascribed to its phytochemical profile. Currently, there are hardly any fine details on the chemical profiling and pharmacological evaluation of this species. In this study, the flavonoids and phenolics contents of the ethanol extracts and four extracted fractions (petroleum ether (PE), ethyl acetate (EA), n-butanol, and water) of the stem bark of Ficus glumosa were firstly quantified. Further, their antioxidant and antiproliferative potentials were also evaluated. The quantitative determination indicated that the EA and n-butanol fractions possessed the highest total flavonoids/phenolics levels of 274.05 ± 0.68 mg RE/g and 78.87 ± 0.97 mg GAE/g, respectively. Similarly, for the 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and ferric-reducing antioxidant power (FRAP) assays, the EA fraction exhibited high potency in both DPPH and ABTS+ scavenging activities with IC50 values of 0.23 ± 0.03 mg/mL, 0.22 ± 0.03 mg/mL, and FRAP potential of 2.81 ± 0.01 mg Fe2+/g, respectively. Furthermore, the EA fraction displayed high cytotoxicity against human lung (A549) and colon (HT-29) cancer cells. Additionally, the liquid chromatography coupled with electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) was employed in order to characterize the chemical constituents of the EA fraction of Ficus glumosa stem bark. Our findings revealed 16 compounds from the EA fraction that were possibly responsible for the strong antioxidant and anti-proliferative properties. This study provides edge-cutting background information on the exploitation of Ficus glumosa as a potential natural antioxidant and anti-cancer remedy.

9.
Antioxidants (Basel) ; 10(3)2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33804549

RESUMO

Warburgia ugandensis, also known as "green heart," is widely used for the treatment of various diseases as a traditional ethnomedicinal plant in local communities in Africa. In this work, 9 and 12 potential superoxide dismutase (SOD) and xanthine oxidase (XOD) ligands from W. ugandensis were quickly screened out by combining SOD and XOD affinity ultrafiltration with LC-MS, respectively. In this way, four new lignanamides (compounds 11-14) and one new macrocyclic glycoside (compound 5), along with three known compounds (compounds 1, 3, and 7), were isolated and identified firstly in this species. The structures of the new compounds were elucidated by spectroscopic analysis, including NMR and UPLC-QTOF-MS/MS. Among these compounds, compound 14 showed the highest 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azinobis-(3-ethylbenzthiazoline)-6-sulfonic acid (ABTS) radical scavenging activities, and total ferric-reducing antioxidant power (FRAP) with IC50 values of 6.405 ± 0.362 µM, 5.381 ± 0.092 µM, and 17.488 ± 1.625 mmol TE/g, respectively. Moreover, compound 14 displayed the highest inhibitory activity on cyclooxygenase-2 (COX-2) with IC50 value of 0.123 ± 0.004 µM, and the ranking order of other compounds' IC50 values was 13 > 11 > 7 > 1 > 12. The present study suggested that lignanamides might represent interesting new characteristic functional components of W. ugandensis to exert remarkable antioxidant and anti-inflammatory activities. Moreover, compound 14, a new arylnaphthalene lignanamide, would be a highly potential natural antioxidant and anti-inflammatory agent from W. ugandensis.

10.
Food Chem ; 333: 127478, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32663752

RESUMO

Moringa oleifera Lam. (M. oleifera) leaves have long been consumed as both nutritive vegetable and popular folk medicine for hyperglycemia and hyperlipidemia in Kenya communities. In the current study, in vitro inhibition by M. oleifera leaf extract (MOLE, 90% (v/v) ethanol) of α-glucosidase and pancreatic lipase was demonstrated, followed by determination of the effects of MOLE on both glucose consumption and lipid levels (TC, TG, HDL-C and LDL-C) in 3T3-L1 cells. Potential ligands in MOLE were fast screened using affinity ultrafiltration LC-MS, and 14 and 10 components displayed certain binding affinity to α-glucosidase and pancreatic lipase, respectively. Docking studies revealed the binding energies and hydrogen bonds between potential ligands and enzymes. This study suggests that M. oleifera leaves may be a promising natural source for the prevention and treatment of hyperglycemia and hyperlipidemia as well as a functional food or other product for health care in the near future.


Assuntos
Moringa oleifera/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Células 3T3-L1 , Animais , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Hipolipemiantes/química , Hipolipemiantes/farmacologia , Lipase/antagonistas & inibidores , Metabolismo dos Lipídeos/efeitos dos fármacos , Camundongos
11.
Pharmaceuticals (Basel) ; 13(4)2020 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-32225055

RESUMO

Rhamnus prinoides L'Herit (R. prinoides) has long been widely consumed as folk medicine in Kenya and other Africa countries. Previous studies indicated that polyphenols were abundant in genus Rhamnus and exhibited outstanding antioxidant and anti-inflammatory activities. However, there are very few studies on such pharmacological activities and the polyphenol profile of this plant up to now. In the present study, the antioxidant activities of the crude R. prinoides extracts (CRE) and the semi-purified R. prinoides extracts (SPRE) of polyphenol enriched fractions were evaluated to show the strong radical scavenging effects against 1,1-diphenyl-2- picrylhydrazyl radical 2,2-diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl (DPPH) (0.510 ± 0.046 and 0.204 ± 0.005, mg/mL), and 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) (0.596 ± 0.005 and 0.096 ± 0.004, mg/mL), respectively. Later, the SPRE with higher contents of polyphenols and flavonoids displayed obvious anti-inflammatory activities through reducing the NO production at the dosage of 11.11 - 100 µg/mL, and the COX-2 inhibitory activity with an IC50 value at 20.61 ± 0.13 µg/mL. Meanwhile, the HPLC-UV/ESI-MS/MS analysis of polyphenol profile of R. prinoides revealed that flavonoids and their glycosides were the major ingredients, and potentially responsible for its strong antioxidant and anti-inflammatory activities. For the first time, the present study comprehensively demonstrated the chemical profile of R. prinoides, as well as noteworthy antioxidant and anti-inflammatory activities, which confirmed that R. prinoides is a good natural source of polyphenols and flavonoids, and provided valuable information on this medicinal plant as folk medicine and with good potential for future healthcare practice.

12.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 42(1): 30-36, 2020 Feb 28.
Artigo em Chinês | MEDLINE | ID: mdl-32131937

RESUMO

Objective To investigate the protective effect of salvianolic acid B(SAB)on the intestinal tract of rats after intestinal ischemia-reperfusion injury(IIRI). Methods Forty-eight healthy male SD rats were equally randomized into IIRI group,SAB+IIRI group,sham control group,and SAB+sham control group. The malonyldialdehyde(MDA)level and superoxide dismutase(SOD)activity in the ileum were measured in each group according to the kit instructions,the transcription levels of inflammatory factors in the ileum of rats were detected by real-time fluorescence quantitative RT-PCR,the secretion level of inflammatory factors was detected by ELISA,and the effects of intestinal ischemia-reperfusion on intestinal permeability and histological lesions were measured by histopathology. Results The MDA level in IIRI group was significantly higher than those in negative control group(P=0.005)and SAB+IIRI group(P=0.012). SOD activity of IIRI group was significantly lower than those of negative control group(P=0.006)and SAB+IIRI group(P=0.017). The optical densities of tumor necrosis factor-α(TNF-α)(P=0.003,P=0.009),interleukin(IL)-1ß(P=0.026,P=0.005),IL-6(P=0.015,P=0.003),and nuclear factor kappa-B(NF-κB)(P=0.007,P=0.015)in IIRI group were significantly higher than those in sham control group and SAB+IIRI group. The TNF-α(P=0.002,P=0.006),IL-1ß(P=0.002,P=0.006),IL-6(P=0.008,P=0.002),and NF-κB(P=0.026,P=0.005)levels in IIRI group were significantly higher than those in sham control group and SAB+IIRI group. The inulin level in IIRI group was significantly lower than that in negative control group(P=0.015)and significantly higher than that in SAB+IIRI group(P=0.011). The dextran level in IIRI group was significantly lower than those in sham control group(P=0.011)and SAB+IIRI group(P=0.012). The dextran gel level in IIRI group was significantly higher than those in sham control group(P=0.031)and SAB+IIRI group(P=0.020). SAB pretreatment remarkably improved the edema,necrosis,and villus stripping of the intestinal mucosa in the ileum of rats. The Chiu score was significantly higher in SAB+sham control group than in sham control group(P=0.001)and was significantly lower in SAB+IIRI group than in IIRI group(P=0.001). Conclusion SAB pretreatment can alleviate IIRI in rat models,and this protective effect may be achieved by alleviating oxidative stress and inflammation in the intestinal tract.


Assuntos
Benzofuranos/farmacologia , Intestinos/lesões , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Citocinas/metabolismo , Inflamação , Masculino , Estresse Oxidativo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
13.
Antioxidants (Basel) ; 8(8)2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31404978

RESUMO

Moringa oleifera Lam. (M. oleifera) is commonly distributed and utilized in tropical and sub-tropical areas. There has been a large number of reports on the antioxidant and anti-inflammatory activity of its leaves, but only a few about its seeds and roots. Hence, in this work we aimed to systematically compare the antioxidant and anti-inflammatory activities of the ethanol crude extracts of leaves, seeds, and roots of M. oleifera from Kenya, and further correlate the differential activities with the chemical constituents from these three parts. The antioxidant activities were measured by using three different assays (DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2'-azinobis-(3-ethylbenzthiazoline-6-sulfonic acid) and FRAP (Ferric-Reducing Antioxidant Power), respectively). Results showed that the leaf extracts displayed the highest DPPH radical scavenging and FRAP total reducing power activities with IC50 values of 1.02 ± 0.13 mg/mL and 0.99 ± 0.06 mM Fe2+/g, respectively; the leaf and root extracts exhibited potential ABTS radical scavenging activities with the IC50 values of 1.36 ± 0.02 and 1.24 ± 0.03 mg/mL. Meanwhile, the leaf and seed extracts (11.1-100 µg/mL) also exerted obvious anti-inflammatory activities, as indicated by the inhibition of NO production. To further reveal correlations between these differential activities with the chemical constituents in the three organs, the total flavonoids content (TFC) of the three different extracts were evaluated, and the TFC of leaves, seeds and roots were found to be 192.36 ± 2.96, 5.89 ± 0.65 and 106.79 ± 2.12 mg rutin equivalent (RE)/g, respectively. These findings indicated the important impacts of the total flavonoid contents on antioxidant and anti-inflammatory activities. Additionally, we further determined the phytochemical profiles of M. oleifera by HPLC-UV/ESI-MS/MS, and identified most of the chemical constituents of leaves as flavonoids. In summary, the leaves of M. oleifera are a better potential natural source of antioxidants and anti-inflammatory agents, and very promising for development into the health promoting dietary supplements.

14.
J Chromatogr A ; 1600: 41-45, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31014578

RESUMO

Headspace analysis of the volatile metabolites has been used as a good strategy for monitoring the microbial growth in several applications, but never been established for the evaluation of the activity of microbial inhibitor in the field of drug screening from natural products. We report on a new method for the determination of antimicrobial activity of drug compounds or crude extracts from natural products by measuring the amount of metabolic carbon dioxide produced in the drug-bacteria incubation system. 2 mL of medium containing bacteria and drug of interest was incubated at 37 °C for 24 h. The amount of metabolic carbon dioxide partitioned in the headspace was measured to evaluate the drug antimicrobial activity using headspace gas chromatography (HS-GC) coupled with thermal conductive detector (TCD). The principle and the standard procedure of the present method have been developed and verified. As a result, the precision of the present method was less than 4% (expressed as relative standard deviation), and an excellent agreement was found on both inhibition rate (R2 = 0.935) and the half inhibition concentration (R2 = 0.994) between the present method and a reference method (optical density method). By comparison, the present method is simpler and safer regarding the microorganism contamination due to the in-situ incubation and detection in the closed system, and suitable for the routine analysis of antimicrobial activity of natural products with high flexibility in both bacterial strains and sample properties.


Assuntos
Anti-Infecciosos/farmacologia , Bactérias Aeróbias/efeitos dos fármacos , Produtos Biológicos/farmacologia , Dióxido de Carbono/análise , Cromatografia Gasosa , Bactérias Aeróbias/metabolismo , Contaminação de Medicamentos/prevenção & controle
15.
Food Chem ; 277: 706-712, 2019 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-30502207

RESUMO

The antioxidant and anti-inflammatory mechanisms of action of flavonoids in lotus plumule were systematically analyzed using radical scavenging assays and ELISA kits. By this means, flavonoids displayed significant antioxidant activity by donating electron, H atom as well as capturing DPPH and ABTS+ free radicals, and anti-inflammatory effect by inhibiting the production of the inflammatory mediators (NO radicals, PGE2 and TNF-α) and pro-inflammatory cytokines (IL-1ß and IL-6). Meanwhile, the bioactive components against inflammation targeting COX-2 were also revealed using ultrafiltration coupled to LC-MS (UF-LC/MS). In this way, 12 components showing specific binding to COX-2 were screened out and identified. The structure-activity relationships suggested that flavonoids O-glycosides displayed comparable binding affinities to COX-2 compared with flavonoids C-glycosides and could be considered as the main active components. This study will provide valuable information for the further exploration of lotus plumule as functional foods or in pharmaceutical industries in the near future.


Assuntos
Anti-Inflamatórios/química , Antioxidantes/química , Flavonoides/química , Lotus/metabolismo , Animais , Antioxidantes/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/química , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/metabolismo , Flavonoides/metabolismo , Glicosídeos/química , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Lotus/química , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Extratos Vegetais/química , Células RAW 264.7 , Fator de Necrose Tumoral alfa/metabolismo , Ultrafiltração
16.
Phytochem Anal ; 29(4): 365-374, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29687660

RESUMO

INTRODUCTION: Medicinal plants are gaining increasing attention worldwide due to their empirical therapeutic efficacy and being a huge natural compound pool for new drug discovery and development. The efficacy, safety and quality of medicinal plants are the main concerns, which are highly dependent on the comprehensive analysis of chemical components in the medicinal plants. With the advances in mass spectrometry (MS) techniques, comprehensive analysis and fast identification of complex phytochemical components have become feasible, and may meet the needs, for the analysis of medicinal plants. OBJECTIVE: Our aim is to provide an overview on the latest developments in MS and its hyphenated technique and their applications for the comprehensive analysis of medicinal plants. METHODOLOGY: Application of various MS and its hyphenated techniques for the analysis of medicinal plants, including but not limited to one-dimensional chromatography, multiple-dimensional chromatography coupled to MS, ambient ionisation MS, and mass spectral database, have been reviewed and compared in this work. RESULTS: Recent advancs in MS and its hyphenated techniques have made MS one of the most powerful tools for the analysis of complex extracts from medicinal plants due to its excellent separation and identification ability, high sensitivity and resolution, and wide detection dynamic range. CONCLUSION: To achieve high-throughput or multi-dimensional analysis of medicinal plants, the state-of-the-art MS and its hyphenated techniques have played, and will continue to play a great role in being the major platform for their further research in order to obtain insight into both their empirical therapeutic efficacy and quality control.


Assuntos
Espectrometria de Massas/métodos , Plantas Medicinais/química , Cromatografia Gasosa/métodos , Cromatografia Líquida/métodos , Microfluídica/instrumentação , Extração em Fase Sólida
17.
Sci Rep ; 6: 38284, 2016 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-27922057

RESUMO

Crude Amaryllidaceae alkaloids (AAs) extracted from Lycoris radiata are reported to exhibit significant anti-cancer activity. However, the specific alkaloids responsible for the pharmacodynamic activity and their targets still remain elusive. In this context, we strived to combine affinity ultrafiltration with topoisomerase I (Top I) as a target enzyme aiming to fish out specific bioactive AAs from Lycoris radiata. 11 AAs from Lycoris radiata were thus screened out, among which hippeastrine (peak 5) with the highest Enrichment factor (EF) against Top I exhibited good dose-dependent inhibition with IC50 at 7.25 ± 0.20 µg/mL comparable to camptothecin (positive control) at 6.72 ± 0.23 µg/mL. The molecular docking simulation further indicated the inhibitory mechanism between Top I and hippeastrine. The in vitro antiproliferation assays finally revealed that hippeastrine strongly inhibited the proliferation of HT-29 and Hep G2 cells in an intuitive dose-dependent manner with the IC50 values at 3.98 ± 0.29 µg/mL and 11.85 ± 0.20 µg/mL, respectively, and also induced significant cellular morphological changes, which further validated our screening method and the potent antineoplastic effects. Collectively, these results suggested that hippeastrine could be a very promising anticancer candidate for the therapy of cancer in the near future.


Assuntos
Alcaloides de Amaryllidaceae/química , Antineoplásicos Fitogênicos/química , DNA Topoisomerases Tipo I/química , Proteínas de Escherichia coli/química , Lycoris/química , Inibidores da Topoisomerase I/química , Alcaloides de Amaryllidaceae/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Sítios de Ligação , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , DNA Topoisomerases Tipo I/metabolismo , Ensaios Enzimáticos , Escherichia coli/química , Escherichia coli/enzimologia , Proteínas de Escherichia coli/metabolismo , Células HT29 , Células Hep G2 , Humanos , Cinética , Simulação de Acoplamento Molecular , Raízes de Plantas/química , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Termodinâmica , Inibidores da Topoisomerase I/isolamento & purificação , Inibidores da Topoisomerase I/farmacologia
18.
Onco Targets Ther ; 8: 3211-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26604788

RESUMO

Gliomas are the most common malignant primary brain tumors, and new clinical biomarkers and therapeutic targets are imminently required. MicroRNAs (miRNAs) are a novel class of small non-coding RNAs (∼22nt) involved in the regulation of various biological processes. Here, by using real-time polymerase chain reaction, miRNA-132 was found to be significantly deregulated in glioma tissues. Based on the prediction of the target genes of miR-132, we hypothesized that there is a significant association between miR-132 and matrix metalloproteinase (MMP) 16 (MT3-MMP), a protein of the MMP family. We showed that the up-expression of miR-132 inhibited cell migration and invasion in the human glioma cell lines A172, SHG44, and U87. Furthermore, the overexpression of miR-132 reduced the expression of MMP16 in A172, SHG44, and U87 cells. Taken together, our study suggested that miR-132 affects glioma cell migration and invasion by MMP16 and implicates miR-132 as a metastasis-inhibiting miRNA in gliomas.

19.
Neural Regen Res ; 10(6): 925-31, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26199609

RESUMO

Curcumin has been shown to significantly improve spatial memory impairment induced by HIV-1 gp120 V3 in rats, but the electrophysiological mechanism remains unknown. Using extracellular microelectrode recording techniques, this study confirmed that the gp120 V3 loop could suppress long-term potentiation in the rat hippocampal CA1 region and synaptic plasticity, and that curcumin could antagonize these inhibitory effects. Using a Fura-2/AM calcium ion probe, we found that curcumin resisted the effects of the gp120 V3 loop on hippocampal synaptosomes and decreased Ca(2+) concentration in synaptosomes. This effect of curcumin was identical to nimodipine, suggesting that curcumin improved the inhibitory effects of gp120 on synaptic plasticity, ameliorated damage caused to the central nervous system, and might be a potential neuroprotective drug.

20.
Cell Mol Neurobiol ; 35(5): 679-87, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25662849

RESUMO

Malignant gliomas are the most common primary brain tumors, and the molecular mechanisms involving their progression and recurrence are still largely unclear. Substantial data indicate that the oncogene miR-494-3p is significantly elevated in gliomas, but the molecular functions of miR-494-3p in gliomagenesis are largely unknown. The present study aimed to explore the role of miR-494-3p and its molecular mechanism in human brain gliomas, malignant glioma cell lines, and cancer stem-like cells. The expression level of miR-494-3p in 48 human glioma issues and 8 normal brain tissues was determined using stem-loop real-time polymerase chain reaction (PCR). To study the function of miR-494-3p inhibitor in glioma cells, the miR-494-3p inhibitor lentivirus was used to transfect glioma cells. Transwell invasion system was used to estimate the effects of miR-494-3p inhibitor on the invasiveness of glioma cells. A mouse model was used to test the effect of miR-494-3p inhibitor on glioma proliferation and invasion in vivo. Results showed that the expression of miR-494-3p in human brain glioma tissues was higher than in normal brain tissues. Downregulated expression of miR-494-3p can inhibit the invasion and proliferation and promote apoptosis in glioma cells. Quantitative reverse transcription PCR and Western blotting analysis revealed that the expression of PTEN was increased after downexpression of miR-494-3p in glioma cells (U87 and U251). miR-494-3p inhibitor could prevent migration, invasion, proliferation, and promote apotosis in gliomas through PTEN/AKT pathway. Therefore, the study results have shown that miR-494-3p may act as a therapeutic target in gliomas.


Assuntos
Apoptose , Movimento Celular , Glioblastoma/genética , Glioblastoma/patologia , MicroRNAs/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Glioblastoma/enzimologia , Humanos , Lentivirus/metabolismo , Masculino , Camundongos Nus , MicroRNAs/genética , Pessoa de Meia-Idade , Invasividade Neoplásica , PTEN Fosfo-Hidrolase/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Transfecção , Ensaios Antitumorais Modelo de Xenoenxerto
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