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1.
ACS Appl Mater Interfaces ; 16(7): 8527-8537, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38329426

RESUMO

Bleeding and bacterial infections are crucial factors affecting wound healing. The usage of herbal medicine-derived materials holds great potential for promoting wound healing. However, the uncertain intrinsic effective ingredients and unclear mechanism of action remain great concerns. Herein, inspired by the herbal medicine Ligusticum wallichii, we reported the synthesis of tetramethylpyrazine-derived carbon quantum dots (TMP-CQDs) for promoting wound healing. Of note, the use of TMP as the precursor instead of L. wallichii ensured the repeatability and homogeneity of the obtained products. Furthermore, TMP-CQDs exhibited high antibacterial activity. Mechanically, TMP-CQDs inhibited the DNA repair, biosynthesis, and quorum sensing of the bacteria and induced intracellular reactive oxygen species (ROS). Moreover, TMP-CQDs could accelerate blood coagulation through activating factor VIII and promoting platelet aggregation. Effective wound healing was achieved by using TMP-CQDs in the Staphylococcus aureus-infected mouse skin wound model. This study sheds light on the development of herbal medicine-inspired materials as effective therapeutic drugs.


Assuntos
Medicamentos de Ervas Chinesas , Pontos Quânticos , Camundongos , Animais , Carbono , Pontos Quânticos/uso terapêutico , Antibiose , Coagulação Sanguínea , Cicatrização , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico
2.
J Colloid Interface Sci ; 662: 39-47, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38335738

RESUMO

The combination of theoretical calculations and experimental synthesis provides valuable insights into the performance of FexNiyO4 as a catalyst for ammonia (NH3) synthesis through the electrocatalytic nitrate reduction reaction (eNO3-RR). Here, an observation of a volcano-shaped trend in the theoretical calculations reveals that the catalytic activity of FexNiyO4 for NH3 synthesis varies with the Fe/Ni ratio. The subsequent experimental syntheses of FexNiyO4 with different Fe/Ni ratios validate this trend and demonstrate the morphological changes associated with the varying Fe/Ni ratios. The evolution of the FexNiyO4 morphology from nanosheets to sea urchin-like structures, nanowires and nanoflowers composed of rotated nanosheets as the Fe/Ni ratio increases further supports the influence of the composition on the resulting morphology. This morphological diversity can be attributed to the specific growth conditions and self-assembly processes involved in the synthesis. The correlation between the Fe/Ni ratio, morphology and NH3 yield reinforces the theoretical calculations. The observed volcanic trend in the NH3 yield, consistent with the theoretical predictions, indicates that there is an optimal Fe/Ni ratio (Fe2NiO4) with the highest NH3 yield of 12.51 mg h-1 cm-2 at -1.1 V. The excellent Faradaic efficiency of 95.97 % in neutral solution further highlights the suitability of Fe2NiO4 as a catalyst for NH3 synthesis through eNO3-RR. Moreover, the remarkable stability of FexNiyO4, regardless of the Fe/Ni ratio, is an important finding. The consistent performance of FexNiyO4 indicates its potential for long-term and practical applications in NH3 synthesis. Furthermore, the observed morphological changes, volcano-shaped trend in the NH3 yield and remarkable stability of FexNiyO4 highlight its potential as a promising catalyst.

3.
Arch Biochem Biophys ; 743: 109677, 2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-37356608

RESUMO

The low-dose combination of Arsenite (As3+) and selenite (Se4+) has the advantages of lower biological toxicity and better curative effects for acute promyelocytic leukemia (APL) therapy. However, the underlying mechanisms remain unclear. Here, based on the fact that the combination of 2 µM A3+ plus 4 µM Se4+ possessed a stronger anti-leukemic effect on APL cell line NB4 as compared with each individual, we employed iTRAQ-based quantitative proteomics to identify a total of 58 proteins that were differentially expressed after treatment with As3+/Se4+ combination rather than As3+ or Se4+ alone, the majority of which were involved in spliceosome pathway. Among them, eight proteins stood out by virtue of their splicing function and significant changes. They were validated as being decreased in mRNA and protein levels under As3+/Se4+ combination treatment. Further functional studies showed that only knockdown of two splicing factors, SF3A3 and SRSF5, suppressed the growth of NB4 cells. The reduction of SF3A3 was found to cause G1/S cell cycle arrest, which resulted in proliferation inhibition. Moreover, SRSF5 downregulation induced cell apoptosis through the activation of caspase-3. Taken together, these findings indicate that SF3A3 and SRSF5 function as pro-leukemic factors and can be potential novel therapeutic targets for APL.


Assuntos
Leucemia Promielocítica Aguda , Humanos , Leucemia Promielocítica Aguda/tratamento farmacológico , Leucemia Promielocítica Aguda/genética , Leucemia Promielocítica Aguda/metabolismo , Linhagem Celular Tumoral , Morte Celular , Apoptose , Proliferação de Células , Tretinoína
4.
Toxicol Appl Pharmacol ; 467: 116511, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-37031722

RESUMO

The interaction between the unfolded protein response (UPR) and autophagy plays either pro-survival or pro-apoptotic roles in the treatment of acute promyelocytic leukemia (APL). Our previous study has shown that the combination therapy of arsenite (As3+) and selenite (Se4+) induces apoptosis in APL NB4 cells, although the mechanisms are not clear. Here, we demonstrate that the interaction between heat shock protein 90 (Hsp90)-mediated UPR and autophagy is the core module for As3+/Se4+ combination-induced apoptosis. Hsp90 overexpression and knockdown assays indicate that Hsp90 inhibition by PERK modulates two branches of the UPR, leading to the activation of ATF4 and CHOP, causing the degradation of IRE1α and the dephosphorylation of eIF2α, thereby contributing to switching the cytoprotective UPR into an apoptotic pathway. Assays using pretreatment with inducers and inhibitors of endoplasmic reticulum stress (ERS) and autophagy reveal that autophagy is stimulated by ERS but suppressed by As3+/Se4+ combination via the mTOR signaling pathway. However, inhibition of autophagy decreases GRP78 expression and eIF2α phosphorylation, thereby further promoting ERS-induced apoptosis. Moreover, As3+/Se4+ combination blocks hepatic infiltration in an APL-NCG mouse model of extramedullary infiltration. Taken together, these findings provide novel agents and therapeutic approaches for APL.


Assuntos
Leucemia Promielocítica Aguda , Proteínas Serina-Treonina Quinases , Animais , Camundongos , Proteínas Serina-Treonina Quinases/metabolismo , Endorribonucleases/metabolismo , Leucemia Promielocítica Aguda/tratamento farmacológico , Leucemia Promielocítica Aguda/metabolismo , eIF-2 Quinase/metabolismo , Resposta a Proteínas não Dobradas , Estresse do Retículo Endoplasmático , Apoptose , Proteínas de Choque Térmico HSP90/metabolismo , Autofagia
5.
Anal Chem ; 95(11): 5034-5044, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36898151

RESUMO

Adenosine triphosphate (ATP), as an important intracellular energy currency produced in mitochondria, is closely related to various diseases in living organisms. Currently, the biological application of AIE fluorophore as a fluorescent probe for ATP detection in mitochondria is rarely reported. Herein, D-π-A and D-A structure-based tetraphenylethylene (TPE) fluorophores were employed to synthesize six different ATP probes (P1-P6), and the phenylboronic acid groups and dual positive charge sites of probes could interact with the vicinal diol of ribose and negatively charged triphosphate structure of ATP, respectively. However, P1 and P4 with a boronic acid group and a positive charge site had poor selectivity for ATP detection. In contrast, P2, P3, P5, and P6 with dual positive charge sites exhibited better selectivity than P1 and P4. In particular, P2 had more advantages of high sensitivity, selectivity, and good time stability for ATP detection than P3, P5, and P6, which was ascribed to its D-π-A structure, linker 1 (1,4-bis(bromomethyl)benzene), and dual positive charge recognition sites. Then, P2 was employed to detect ATP, and it exhibited a low detection limit of 3.62 µM. Moreover, P2 showed utility in the monitoring of mitochondrial ATP level fluctuations.


Assuntos
Corantes Fluorescentes , Estilbenos , Corantes Fluorescentes/química , Trifosfato de Adenosina , Mitocôndrias
6.
J Pharm Pharmacol ; 75(6): 764-783, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-36847133

RESUMO

OBJECTIVES: This study aimed to comprehensively investigate the potential active components and therapeutic mechanisms of Shen-Kui-Tong-Mai granule (SKTMG) in the treatment of heart failure. METHODS: Network pharmacology combined with ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS), molecular docking, and in vivo validation was performed to identify the active components and the potential targets for SKTMG to improve chronic heart failure (CHF). KEY FINDINGS: The network pharmacology identified 192 active compounds and 307 potential consensus targets for SKTMG. On the other hand, network analysis discovered 10 core target genes related to the MAPK signal pathway. These genes include AKT1, STAT3, MAPK1, P53, SRC, JUN, TNF, APP, MAPK8 and IL6. The molecular docking results revealed that the SKTMG components were luteolin, quercetin, astragaloside IV and kaempferol, which could bind AKT1, MAPK1, P53, JUN, TNF and MAPK8. Additionally, SKTMG inhibited phosphorylation of AKT, P38, P53 and c-JUN, and reduced TNF-α expression in CHF rats. CONCLUSIONS: The present results demonstrated that network pharmacology combined with UHPLC-MS/MS, molecular docking and in vivo validation can facilitate the identification of active components and the potential targets for SKTMG to improve CHF.


Assuntos
Medicamentos de Ervas Chinesas , Insuficiência Cardíaca , Animais , Ratos , Simulação de Acoplamento Molecular , Farmacologia em Rede , Espectrometria de Massas em Tandem , Proteína Supressora de Tumor p53 , Doença Crônica , Medicamentos de Ervas Chinesas/farmacologia , Insuficiência Cardíaca/tratamento farmacológico
7.
Inorg Chem ; 62(5): 2236-2243, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36689619

RESUMO

Two zero-dimensional inorganic-organic hybrids, namely, [C4mim][Cd(TCDPPA)3] (1) and [C4mpy][Cd(TCDPPA)3] (2), where (TCDPPA)- = 2,2,2-trichloro-N-(di(pyrrolidin-1-yl)phosphoryl)acetamide, (C4mim)+ = 1-butyl-3-methylimidazolium, and (C4mpy)+ = 1-butyl-4-methylpyridinium, have been synthesized via metathesis reactions and characterized systematically. These ionic cadmium-containing inorganic-organic hybrid compounds are assembled from a bulky organic cation and a complex anion constructed from the chelation of three TCDPPA ligands to one cadmium ion. These compounds possess wide band gaps and emit in the deep-blue region intensely with a quantum yield as high as 34.04%. The success of this work provides a new method for the design and fabrication of high-efficiency blue-emitting materials.

9.
Perfusion ; 38(3): 557-566, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35102779

RESUMO

BACKGROUND: Atherosclerosis (AS), one of the leading causes of deaths and disabilities, is a kind of vascular disease of lipid disorders and chronic inflammation. Guanxinping (GXP) has been administrated in the treatment of AS for nearly 20 years with satisfying clinical response. This study aimed to explore its underlying mechanisms of anti-atherosclerotic effect in AS. METHODS: Male ApoE-/- mice were randomized into five groups and fed with either standard diet (control group, CON) or high-fat diet (HFD) for 12 weeks. HFD mice were further divided randomly and either fed continually with HFD as a model group, or atorvastatin (ATO), or low-dose GXP (LGXP), or high-dose GXP (HGXP). After 12 weeks, the body weight, serum triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-c), and low-density lipoprotein cholesterol (LDL-c) were detected. Moreover, serum inflammation cytokines including tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1ß (IL-1ß) concentrations were measured. The structure of aortic tissues was examined by hematoxylin-eosin staining. The mRNA expression of TNF-α, IL-6, and IL-1ß were assessed by qPCR. The protein expressions of ICAM-1, VCAM-1, MCP-1, IL-6, IL-1ß, p38MAPK, ERK1/2, JNK, IκB-α, and NF-κBp65 in the aorta were also detected. RESULTS: GXP treatment reduced serum TG, TC, and LDL-c levels in ApoE-/- mice. Moreover, GXP reduced lipid accumulation in the aorta of ApoE-/- mice, induced by HFD. Furthermore, GXP ameliorated the aorta morphological damage and reduced the serum TNF-α, IL-6, and IL-1ß levels. GXP also attenuated the protein expression of ICAM-1, VCAM-1, MCP-1, IL-6, IL-1ß, p38MAPK, ERK1/2, JNK, and NF-κBp65, whereas it increased the IκBα level in aortic tissues of ApoE-/- mice. CONCLUSIONS: Our results show that GXP could ameliorate atherosclerosis, which is mediated by inhibition of the MAPK/NF-κB signaling pathway in ApoE-/- mice. This study provides evidence that GXP might be a promising drug for the treatment of AS.


Assuntos
Aterosclerose , NF-kappa B , Masculino , Camundongos , Animais , NF-kappa B/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Molécula 1 de Adesão Intercelular/farmacologia , Molécula 1 de Adesão Intercelular/uso terapêutico , Sistema de Sinalização das MAP Quinases , Interleucina-6 , Fator de Necrose Tumoral alfa , LDL-Colesterol/metabolismo , LDL-Colesterol/farmacologia , LDL-Colesterol/uso terapêutico , Molécula 1 de Adesão de Célula Vascular/metabolismo , Molécula 1 de Adesão de Célula Vascular/farmacologia , Molécula 1 de Adesão de Célula Vascular/uso terapêutico , Aterosclerose/genética , Transdução de Sinais , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Apolipoproteínas E/farmacologia , Camundongos Endogâmicos C57BL
10.
iScience ; 25(8): 104773, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-35992091

RESUMO

Colorectal cancer is one of the most serious tumors and berberine can inhibit the recurrence and transformation of colorectal adenoma into colorectal cancer. However, the direct binding target proteins of berberine in inhibiting colorectal cancer remain unclear. In this study, the chemical proteomics method was used and demonstrated that berberine is directly bound to pyruvate kinase isozyme type M2 (PKM2) in colorectal cancer cells. The triangular N-O-O triangular structure of berberine contributed to hydrophobic interaction with I119 amino acid residues and π-π interaction with F244 amino acid residues of PKM2 protein. Moreover, berberine was shown to inhibit the reprogramming of glucose metabolism and the phosphorylation of STAT3, down regulate the expression of Bcl-2 and Cyclin D1 genes, ultimately inhibiting the progression of colorectal cancer. This study uncovered the direct binding target protein and mechanism of berberine to improve metabolic reprogramming in colorectal cancer, which is helpful to guide the optimization of berberine.

11.
Phytomedicine ; 102: 154217, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35660350

RESUMO

BACKGROUND: Colitis-associated cancer (CAC) is known to be a complex combination of tumor cells, non-tumor cells and a large intestinal flora. The increasing role of intestinal flora in CAC may represent a new approach to improving CAC treatment. Berberine can reduce colorectal adenoma recurrence and inhibit colorectal carcinogenesis. PURPOSE: Berberine has demonstrated efficacy for the control and suppression of CAC. Given the low oral absorption into the blood and large intestinal excretion of berberine, intestinal flora may be one of the important targets of berberine inhibiting the occurrence of colorectal cancer (CRC). The purpose of this study was to investigate the effects of berberine on intestinal flora in CAC mice and its ability to remodel intestinal flora to improve short-chain fatty acid metabolism. STUDY DESIGN AND METHODS: The CAC model in mice was induced by Azoxymethane/Dextran sodium sulfate (AOM/DSS). Berberine was administered daily at doses of 50 and 100 mg/kg, and aspirin was used as the positive control. The effect of berberine on colitis-associated colorectal tumorigenesis was assessed by general imaging, tumor counting, and Ki67 staining. Intestinal flora changes were detected by 16S rDNA sequencing technology. Targeted short-chain fatty acid detection was performed by GC-MS/MS, and Lipopolysaccharide (LPS) levels in feces were quantified with an ELISA kit. The signaling pathway of TLR4/NF-κB P65/IL-6/p-STAT3 was evaluated by Western blotting and immunofluorescence. The expression levels of intestinal barrier functional biomarkers Occludin and ZO-1 were detected by immunohistochemistry. Fecal flora transplantation (FMT) was used to evaluate the effect of intestinal flora in inhibiting inflammatory cancer transformation by berberine. RESULTS: Berberine reduced the number and load of tumors in CAC mice. Berberine remodeled the composition of pathogenic and beneficial bacteria in mice with colitis-associated colorectal tumorigenesis. Berberine treatment resulted in increases in fecal butyric acid, acetic acid and propionic acid levels, but did not alter isobutyric acid, isovaleric acid, valeric acid and caproic acid. In addition, berberine reduced LPS content in feces in mice with colitis-associated colorectal tumorigenesis. Occludin and ZO-1 were upregulated, and the TLR4/p-NF-κB p65/IL-6/p-STAT3 inflammatory-cancer transformation pathway was inhibited with berberine. The FMT results further verified that the berberine-treated intestinal flora was sufficient to alleviate the occurrence of colonic tumors associated with colitis in mice. CONCLUSION: Our study showed that berberine alleviated the colitis-associated colorectal tumorigenesis from three equilibrium levels: (1) Pathogenic and beneficial bacteria; (2) Short-chain fatty acids and LPS produced by intestinal flora; and (3) Inflammatory cancer transformation signaling and intestinal barrier function. This study provided a new approach and experimental basis for the application of berberine in the treatment of CAC in clinical practice.


Assuntos
Berberina , Colite , Neoplasias Colorretais , Microbioma Gastrointestinal , Animais , Azoximetano , Berberina/farmacologia , Carcinogênese , Transformação Celular Neoplásica , Colite/induzido quimicamente , Colite/complicações , Colite/tratamento farmacológico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Sulfato de Dextrana , Modelos Animais de Doenças , Ácidos Graxos Voláteis , Interleucina-6/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Ocludina , Espectrometria de Massas em Tandem , Receptor 4 Toll-Like
12.
Eur J Pharmacol ; 921: 174864, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35219731

RESUMO

The treatment of fracture delayed union and nonunion has become a challenging problem. Hypoxia inducible factor-1α (HIF-1α) is reported to be a key factor in fracture healing, and is degraded by hydroxylation of prolyl hydroxylase (PHDs) under normal oxygen. Small molecules could inhibit the activity of PHDs, stabilize HIF-1α protein, regulate the expression of downstream target genes of HIF-1α, and make the body adapt to hypoxia. The migration and osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) is the most promising candidate for the treatment of fracture nonunion. Here we reported that IOX2, an HIF-1α PHD inhibitor, markedly improved the proliferation and migration of BMSCs by upregulating intracellular Ca2+ and concomitant decreasing reactive oxygen species (ROS) in vitro, and facilitated the repair of bone fracture by increasing the number of BMSCs and cartilage formation in vivo. No significant influence of IOX2 on the proliferation and migration of BMSCs after silencing of the HIF-1α. Together, our findings indicated that IOX2 promoted the proliferation and migration of BMSCs via the HIF-1α pathway and further accelerated fracture healing. These results provide a deeper understanding of the mechanism by which HIF promotes fracture healing.


Assuntos
Fraturas Ósseas , Células-Tronco Mesenquimais , Humanos , Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Osteogênese , Transdução de Sinais
13.
Artigo em Inglês | MEDLINE | ID: mdl-34484396

RESUMO

BACKGROUND: Global longitudinal strain (GLS) can be assessed by speckle tracking echocardiography (STE) to express the degree of cardiac fibrosis. Qianyangyuyin (QYYY) granules can effectively improve GLS in hypertensive patients. Using a hypertensive rat model, we carried out speckle tracking echocardiography to validate the effect of QYYY in diminishing LV remodeling. METHODS: We randomly divided 16 spontaneously hypertensive rats (SHRs) into SHR, SHR + valsartan (SHR + V), SHR + low-dose QYYY (SHR + QL), and SHR + high-dose QYYY (SHR + QH) groups, with four rats in each group. Another group of 4 Wistar-Kyoto (WKY) rats were selected into a normal control (WKY) group. At the 8th week, conventional echocardiographic parameters were measured by GE Vivid E95 ultrasound (12S probe, 10-12 MHz) and GLS by speckle tracking echocardiography with EchoPAC (version 203) software. HE and Masson's trichrome staining were performed to detect the cardiomyocyte width and collagen volume fraction after rat sacrifice. Collagen I, α-SMA, S100A4, TGF-ß, Smad 3, MYH6, and MYH7 were further analyzed by Western blot. RESULTS: The absolute values of GLS significantly increased in the SHR + QH group compared to the SHR group, while the CVF and CW values significantly decreased. In addition, Collagen I, α-SMA, S100A4, TGF-ß, Smad3, MYH7, and MYH7/MYH6 ratio remarkably reduced in the SHR + QH group. The value of GLS could be repetitively measured and positively correlated with the collagen volume fraction of the myocardium and the cardiomyocyte width of the left ventricular free wall. CONCLUSIONS: GLS is a reliable indicator to evaluate the therapeutic effect on left ventricular remodeling in hypertension. QYYY granules can inhibit the development of cardiac fibrosis in the hypertensive rat model.

14.
Food Sci Nutr ; 9(9): 4711-4721, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34531985

RESUMO

This study aims to determine the effects and mechanism of action of muscone on the biological activity of the gastric cancer cell lines SGC-7901 and MGC-803 (proliferation, apoptosis, invasion, and migration) in vitro. An optimal muscone concentration was determined using MTT and cell apoptosis tests. The SGC-7901 and MGC-803 cells were divided into five groups: normal control, muscone, miRNA, muscone + miRNA, and muscone + miRNA inhibitor. Cell proliferation rate, apoptosis rate, cell cycle phase distribution, number of invading cells, and wound healing rate were compared among the five groups using MTT, flow cytometry, transwell, and wound healing assays. Relative expression levels of the proteins PI3K, AKT, P21, c-Myc, MMP-2, and MMP-9 were measured by Western blot. Compared with the control group, the groups treated with muscone and miRNA showed significantly lower cell proliferation rate, number of invading cells, and wound healing rate (p < .05 for all), but significantly higher rates of cell apoptosis rate and numbers of cells in the G1 phase (p < .05 for all). These groups also showed significantly lower expression of the proteins PI3K, AKT, c-Myc, MMP-2, and MMP-9 but significantly increased expression of the protein P21 (p < .05). Transfecting muscone-treated SGC-7901 and MGC-803 cells with miRNA-145 inhibitor resulted in a significant recovery of biological activity (p < .05). Muscone suppresses the biological activity of SGC-7901 and MGC-803 gastric cancer cells in vitro via regulation of miRNA-145.

15.
ACS Appl Mater Interfaces ; 13(39): 46659-46664, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34569784

RESUMO

Ambient electrochemical oxygen reduction into valuable hydrogen peroxide (H2O2) via a selective two-electron (2e-) pathway is regarded as a sustainable alternative to the industrial anthraquinone process, but it requires advanced electrocatalysts with high activity and selectivity. In this study, we report that Mn-doped TiO2 behaves as an efficient electrocatalyst toward highly selective H2O2 synthesis. This catalyst exhibits markedly enhanced 2e- oxygen reduction reaction performance with a low onset potential of 0.78 V and a high H2O2 selectivity of 92.7%, much superior to the pristine TiO2 (0.64 V, 62.2%). Additionally, it demonstrates a much improved H2O2 yield of up to 205 ppm h-1 with good stability during bulk electrolysis in an H-cell device. The significantly boosted catalytic performance is ascribed to the lattice distortion of Mn-doped TiO2 with a large amount of oxygen vacancies and Ti3+. Density functional theory calculations reveal that Mn dopant improves the electrical conductivity and reduces ΔG*OOH of pristine TiO2, thus giving rise to a highly efficient H2O2 production process.

16.
Foods ; 10(7)2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34359486

RESUMO

A novel sorbent based on the ZrO2 nanoparticles and poly(diallyldimethylammonium chloride)-modified graphene oxide aerogel-grafted stainless steel mesh (ZrO2/PDDA-GOA-SSM) was used for the extraction and detection of organophosphorus pesticides (OPPs). Firstly, the PDDA and GO composite was grafted onto the surface of SSM and then freeze-dried to obtain the aerogel, which efficiently reduced the accumulation of graphene nanosheets. It integrated the advanced properties of GOA with a thin coating and the three-dimensional structural geometry of SSM. The modification of ZrO2 nanoparticles brought a selective adsorption for OPPs due to the combination of the phosphate group as a Lewis base and ZrO2 nanoparticles with the Lewis acid site. The ZrO2/PDDA-GOA-SSM was packed into the solid-phase extraction (SPE) cartridge to extract OPPs. According to the investigation of different factors, the extraction recovery was mainly affected by the hydrophilic-hydrophobic properties of analytes. Effective extraction and elution parameters such as sample volume, sample pH, rate of sample loading, eluent, and eluent volume, were also investigated and discussed. Under the optimal conditions, the linearity of phoxim and fenitrothion was in the range of 1.0-200 µg L-1, and the linearity of temephos was in the range of 2.5-200 µg L-1. The limits of detection were ranged from 0.2 to 1.0 µg L-1. This established method was successfully applied to detect OPPs in two vegetables. There was no OPP detected in real samples, and results showed that the matrix effects were in the range of 46.5%-90.1%. This indicates that the ZrO2/PDDA-GOA-SSM-SPE-HPLC method could effectively extract and detect OPPs in vegetables.

18.
Front Pharmacol ; 12: 667433, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34168560

RESUMO

Protection against hypoxia injury is an important therapeutic strategy for treating hypertensive nephropathy. In this study, the effects of Qian Yang Yu Yin granule (QYYY) on spontaneously hypertensive rats fed with high salt diet and HEK293T cells exposed to hypoxia were investigated. After eight weeks' treatment of QYYY, blood pressure, serum creatinine, serum cystatin C, blood urea nitrogen, urinary ß2-microglobulin, urinary N-acetyl-ß-glucosaminidase, and urinary microalbumin were assessed. The changes of hypoxia-inducible factor-1α (HIF-1α), pyruvate kinase M2 (PKM2), glucose transport 1 (GLUT1), lactate dehydrogenase A (LDH-A), connective tissue growth factor (CTGF), transforming growth factor-ß1 (TGF-ß1), ATP, lactate, pyruvate, and pathology were also assessed in vivo. HEK293T cells pre-treated with QYYY and/or HIF-1α over expressing cells were cultured in a three gas hypoxic incubator chamber (5% CO2, 1% O2, 94% N2) for 12 h and then the expressions of HIF-1α, PKM2, GLUT1, LDH-A, CTGF, TGF-ß1, ATP, lactate, and pyruvate were detected. Our results showed that QYYY promoted the indicators of renal inflammation and fibrosis mediated by HIF-1α/PKM2 positive feedback loop in vivo and vitro. Our findings indicated that QYYY treated hypertensive nephropathy by regulating metabolic reprogramming mediated by HIF-1α/PKM2 positive feedback loop.

19.
Life Sci ; 264: 118684, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33129877

RESUMO

AIMS: Fracture site is regionally hypoxic resulting from vasculature disruption. HIF-1αplays an essential role in fracture repair. This study aims to investigate the influence of FG4592 on the femur fracture of SD rats and the proliferation, migration of BMSCs. MATERIALS AND METHODS: After the femoral fracture model was established, computed tomography imaging and histological analyses were used to quantify bone healing and the expression of CD90, HIF-1α, VEGF were observed by means of immunohistochemistry method on Day 10 and Day 20. In addition, CCK-8 assay, transwell, flow cytometric analysis, laser confocal microscopy assay, western blot and rT-PCR were performed to text the proliferation and migration of BMSCs using FG4592. KEY FINDINGS: In vivo, FG4592 facilitated the repair of bone fracture by increasing the number of BMSCs and cartilage formation. In vitro, FG4592 markedly improved the proliferation, migration of BMSCs via upregulation of intracellular Ca2+, NO and concomitant decrease of ROS. Gene silencing of HIF-1α resulted in the opposite phenomenon in BMSCs with the treatment of FG4592. SIGNIFICANCE: The transplantation of BMSCs is the most promising candidate for the treatment of fracture non-union. We illustrated that FG4592 promoted the proliferation, migration of BMSCs via the HIF/Ca2+/NO/ROS pathway and further accelerated fracture healing. These results provide a deeper understanding for the mechanism of HIF in promoting fracture healing.


Assuntos
Fraturas do Colo Femoral/metabolismo , Glicina/análogos & derivados , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Isoquinolinas/uso terapêutico , Transplante de Células-Tronco Mesenquimais/métodos , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Células da Medula Óssea/metabolismo , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Células Cultivadas , Fraturas do Colo Femoral/diagnóstico por imagem , Fraturas do Colo Femoral/terapia , Consolidação da Fratura/efeitos dos fármacos , Consolidação da Fratura/fisiologia , Glicina/farmacologia , Glicina/uso terapêutico , Isoquinolinas/farmacologia , Masculino , Células-Tronco Mesenquimais/metabolismo , Ratos , Ratos Sprague-Dawley
20.
BMC Complement Med Ther ; 20(1): 291, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32967687

RESUMO

BACKGROUND: The balance between T helper 17 (Th17) cells and regulatory T cells (Tregs) is involved in immunological tolerance. Destruction of immunological tolerance by dendritic cell (DC)-mediated T cells is involved in the pathogenesis of ulcerative colitis (UC). Qingchang Huashi granule (QCHS) has been confirmed in the treatment of UC involved by inhibiting the activation of DCs. The aim of this study was to investigate the mechanism through which QCHS restores the Th17/Treg balance by modulating DCs in the treatment of UC. METHODS: The effects of QCHS on Th17 cells, Tregs and DCs were detected in a 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced experimental colitis model. Furthermore, we injected QCHS-treated DCs into colitis model to test whether QCHS modulates the Th17/Treg balance via DCs. Tregs and Th17 cells were analyzed by FACS. IL-10, IL-17, and Foxp3 were measured by ELISA, Western blot and qRT-PCR. RESULTS: Both QCHS and QCHS-treated DCs improved colonic histopathology, diminished Th17 cell differentiation and inhibited IL-17 production while promoting CD4+CD25+Foxp3+ Treg differentiation and augmenting IL-10 and Foxp3 expression in colitis mice. Additionally, QCHS reduced CD86 and MHC-II expression on DCs, decreased IL-12 production ex vivo and restored the Th17/Treg ratio in the colitis model. CONCLUSION: The findings of this study indicate that QCHS ameliorates TNBS-induced colitis by restoring the DC-mediated Th17/Treg balance.


Assuntos
Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/imunologia , Células Dendríticas/imunologia , Medicamentos de Ervas Chinesas/farmacologia , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Animais , Diferenciação Celular , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ácido Trinitrobenzenossulfônico
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