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BACKGROUND: Psoriasis is a common chronic inflammatory skin disease. Keratinocytes hyperproliferation and excessive inflammatory response contribute to psoriasis pathogenesis. The agents able to attenuate keratinocytes hyper-proliferation and excessive inflammatory response are considered to be potentially useful for psoriasis treatment. Daphnetin exhibits broad bioactivities including anti-proliferation and anti-inflammatory. This study aims to evaluate the anti-psoriatic potential of daphnetin in vitro and in vivo, and explore underlying mechanisms. METHODS: HaCaT keratinocytes was stimulated with the mixture of IL-17A, IL-22, oncostatin M, IL-1α, and TNF-α (M5) to establish psoriatic keratinocyte model in vitro. Cell viability was measured using Cell Counting Kit-8 (CCK-8). Quantitative Real-Time PCR (qRT-PCR) was performed to measure the mRNA levels of hyperproliferative marker gene keratin 6 (KRT6), differentiation marker gene keratin 1 (KRT1) and inflammatory factors IL-1ß, IL-6, IL-8, TNF-α, IL-23A and MCP-1. Western blotting was used to detect the protein levels of p65 and p-p65. Indirect immunofluorescence assay (IFA) was carried out to detect p65 nuclear translocation. Imiquimod (IMQ) was used to construct psoriasis-like mouse model. Psoriasis severity (erythema, scaling) was scored based on Psoriasis Area Severity Index (PASI). Hematoxylin and eosin (H&E) staining was performed to examine histological change in skin lesion. The expression of inflammatory factors including IL-6, TNF-α, IL-23A and IL-17A in skin lesion was measured by qRT-PCR. RESULTS: Daphnetin attenuated M5-induced hyperproliferation in HaCaT keratinocytes. M5 stimulation significantly upregulated mRNA levels of IL-1ß, IL-6, IL-8, TNF-α, IL-23A and MCP-1. However, daphnetin treatment partially attenuated the upregulation of those inflammatory cytokines. Daphnetin was found to be able to inhibit p65 phosphorylation and nuclear translocation in HaCaT keratinocytes. In addition, daphnetin significantly ameliorate the severity of skin lesion (erythema, scaling and epidermal thickness, inflammatory cell infiltration) in IMQ-induced psoriasis-like mouse model. Daphnetin treatment attenuated IMQ-induced upregulation of inflammatory cytokines including IL-6, IL-23A and IL-17A in skin lesion of mice. CONCLUSIONS: Daphnetin was able to attenuate proliferation and inflammatory response induced by M5 in HaCaT keratinocytes through suppression of NF-κB signaling pathway. Daphnetin could ameliorate the severity of skin lesion and improve inflammation status in IMQ-induced psoriasis-like mouse model. Daphnetin could be an attractive candidate for future development as an anti-psoriatic agent.
Subject(s)
Humans , Animals , Mice , Rabbits , Psoriasis/chemically induced , Psoriasis/drug therapy , Umbelliferones/pharmacology , Adjuvants, Immunologic/adverse effects , Imiquimod/adverse effects , Inflammation/drug therapy , Anti-Inflammatory Agents/pharmacology , Keratinocytes , Cell Proliferation , Mice, Inbred BALB CABSTRACT
Objective: To investigate the effect of daphnetin (DAP) combined with insulin-like growth factor 1 (IGF-1) gene transfection on chondrogenic differentiation of adipose-derived mesenchymal stem cells (ADSCs) in rats. Methods: Rat ADSCs were isolated and amplified by enzymatic digestion. The third generation ADSCs were treated with IGF-1 gene transfection as experimental group and normal ADSCs as control group. The cells of the two groups were treated with different concentrations of DAP (0, 30, 60, 90 μg/mL), respectively. Cell proliferation was detected by cell counting kit 8 (CCK-8) after cultured for 72 hours. After 14 days, real-time fluorescence quantitative PCR and Western blot were used to detect the mRNA and protein expressions of chondrocyte markers (collagen type Ⅱ and Aggrecan) in each group; and toluidine blue staining and collagen type Ⅱ immunohistochemical staining were performed. Results: CCK-8 assay showed that with the increase of DAP concentration, the cell absorbance ( A) value of the control group and the experimental group increased gradually ( P0.05). But the mRNA and protein expressions of collagen type Ⅱ and Aggrecan in the experimental group increased gradually, and the 60 and 90 μg/mL DAP concentration groups were significantly higher than 0 μg/mL DAP concentration group ( P<0.05). At the same DAP concentration, the relative mRNA and protein expressions of collagen type Ⅱ and Aggrecan were significantly higher in the experimental group than in the control group ( P<0.05). Toluidine blue staining showed that with the increase of DAP concentration, there was no significant difference in cell staining between the control group and the experimental group. At the same DAP concentration, the cells in the experimental group were slightly darker than those in the control group. Immunohistochemical staining of collagen type Ⅱ showed that with the increase of DAP concentration, there was no significant difference in the cytoplasmic brown-yellow coloring of the cells in the control group. The cytoplasmic brown-yellow coloring of the cells in the experimental group gradually deepened, with 60 and 90 μg/mL DAP concentration groups significantly deeper than 0 μg/mL DAP concentration group. At the same DAP concentration, the color of the cells in the experimental group was significantly deeper than that in the control group. Conclusion: DAP can promote the proliferation of ADSCs in rats. The differentiation of ADSCs into chondrocytes induced by DAP alone was slightly, but DAP combined with IGF-1 gene transfection has obvious synergistic effect to promote chondrogenic differentiation of ADSCs.
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Daphnetin is quickly eliminated in rats after dosing, but the mechanism remains unclear. This study was aimed to investigate the in vitro metabolism of daphnetin using rat liver S9 fractions (RLS9). The metabolites formed in RLS9 were identified and the kinetic parameters for different metabolic pathways were determined. HPLC-DAD-MS analysis showed that daphnetin was biotransformed to six metabolites, which were identified as 7 or 8 mono-glucuronide and mono-sulfate, 8-methylate, and 7-suflo-8-methylate. Methylation and glucuronidation of daphnetin exhibited the Michaelis-Menten kinetic characteristics, whereas the substrate inhibition kinetic and the two-site kinetic were observed for 8-sulfate and 7-sulfate formations. Of the 3 conjugation pathways, the intrinsic clearance rate for sulfation was highest, followed by methylation and glucuronidation. By in vitro-in vivo extrapolation of the kinetic data measured in RLS9, the hepatic clearance were estimated to be 54.9 mL·min-1·kg-1 which is comparable to the system clearance (58.5 mL·min-1·kg-1) observed in rats. In conclusions, the liver might be the main site for daphnetin metabolism in rats. Sulfation, methylation and glucuronidation are important pathways of the hepatic metabolism of daphnetin in rats.
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To establish HPLC-MS/MS method for simultaneous determination of daphnetin, daphnoretin, and daphneticin in rat plasma after oral and intravenous administration of Daphne giraldii extract, and then use them in the calculation of pharmacokinetic parameters. Six sprague-dawley rats received intragastric administration of D. giraldii extract (daphnetin, daphnoretin and daphneticin were 88.40, 3.24 and 4.28 mg•kg⁻¹, respectively). Their drug plasma concentration was determined by LC-MS/MS with schisandrin as an internal standard to draw plasma concentration-time curve. The pharmacokinetic parameters were calculated by Kinetica 4.4. The results showed that the linear range was 5-1 000 μg•L⁻¹ for daphnetin, daphnoretin and daphneticin, and the method ological test showed conformance to the requirements.The intraday and inter-day variable coefficients (RSD) were both less than 15.0%, indicating that both of legitimate precise and accuracy were consistent with the analysis requirements of biological samples. For daphnetin, the pharmacokinetic parameters Tmax, Cmax, AUC0-t, T1/2 and MRT were 4 h, 858.96 μg•L⁻¹, 10 566.4 μg•L⁻¹•h, 5.19 h and 9.43 h, respectively. For daphnoretin, the pharmacokinetic parameters Tmax, Cmax, AUC0-t, T1/2 and MRT were 2.92 h, 178.00 μg•L⁻¹, 905.89 μg•L⁻¹•h, 3.50 h and 6.95 h, respectively. For daphneticin, the pharmacokinetic parameters Tmax, Cmax, AUC0-t, T1/2 and MRT were 2 h, 36.67 μg•L⁻¹, 355.11 μg•L⁻¹•h, 4.95 h and 8.27 h, respectively. The LC-MS/MS analysis method established in this study was proved to be so accurate and sensitive that it can be applied to the pharmacokinetic study of daphnetin, daphnoretin and daphneticin.
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OBJECTIVE@#To use structure-activity analysis to study the anti-Alzheimer's disease (anti-AD) activity of natural coumarins isolated from Angelica decursiva and Artemisia capillaris, along with one purchased coumarin (daphnetin).@*METHODS@#Umbelliferone, umbelliferone 6-carboxylic acid, scopoletin, isoscopoletin, 7-methoxy coumarin, scoparone, scopolin, and esculetin have been previously isolated; however 2'-isopropyl psoralene was isolated from Angelica decursiva for the first time to evaluate their inhibitory effects against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and β-site amyloid precursor protein cleaving enzyme 1 (BACE1) enzyme activity. We scrutinized the potentials of coumarins as cholinesterase and BACE1 inhibitors via enzyme kinetics and molecular docking simulation.@*RESULTS@#Among the test compounds, umbelliferone 6-carboxylic acid, esculetin and daphnetin exhibited potent inhibitory activity against AChE, BChE and BACE1. Both esculetin and daphnetin have a catechol group and exhibit significant anti-AD activity against AChE and BChE. In contrast, presence of a sugar moiety and methoxylation markedly reduced the anti-AD activity of the coumarins investigated in this study. With respect to BACE1 inhibition, umbelliferone 6-carboxylic acid, esculetin and daphnetin contained carboxyl or catechol groups, which significantly contributed to their anti-AD activities. To further investigate these results, we generated a 3D structure of BACE1 using Autodock 4.2 and simulated binding of umbelliferone 6-carboxylic acid, esculetin and daphnetin. Docking simulations showed that different residues of BACE1 interacted with hydroxyl and carboxylic groups, and the binding energies of umbelliferone 6-carboxylic acid, esculetin and daphnetin were negative (-4.58, -6.25 and -6.37 kcal/mol respectively).@*CONCLUSIONS@#Taken together, our results suggest that umbelliferone 6-carboxylic acid, esculetin and daphnetin have anti-AD effects by inhibiting AChE, BChE and BACE1, which might be useful against AD.
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Objective: To use structure-activity analysis to study the anti-Alzheimer's disease (anti-AD) activity of natural coumarins isolated from Angelica decursiva and Artemisia capillaris, along with one purchased coumarin (daphnetin). Methods: Umbelliferone, umbelliferone 6-carboxylic acid, scopoletin, isoscopoletin, 7-methoxy coumarin, scoparone, scopolin, and esculetin have been previously isolated; however 2'-isopropyl psoralene was isolated from Angelica decursiva for the first time to evaluate their inhibitory effects against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and β-site amyloid precursor protein cleaving enzyme 1 (BACE1) enzyme activity. We scrutinized the potentials of coumarins as cholinesterase and BACE1 inhibitors via enzyme kinetics and molecular docking simulation. Results: Among the test compounds, umbelliferone 6-carboxylic acid, esculetin and daphnetin exhibited potent inhibitory activity against AChE, BChE and BACE1. Both esculetin and daphnetin have a catechol group and exhibit significant anti-AD activity against AChE and BChE. In contrast, presence of a sugar moiety and methoxylation markedly reduced the anti-AD activity of the coumarins investigated in this study. With respect to BACE1 inhibition, umbelliferone 6-carboxylic acid, esculetin and daphnetin contained carboxyl or catechol groups, which significantly contributed to their anti-AD activities. To further investigate these results, we generated a 3D structure of BACE1 using Autodock 4.2 and simulated binding of umbelliferone 6-carboxylic acid, esculetin and daphnetin. Docking simulations showed that different residues of BACE1 interacted with hydroxyl and carboxylic groups, and the binding energies of umbelliferone 6-carboxylic acid, esculetin and daphnetin were negative (-4.58, -6.25 and -6.37 kcal/mol respectively). Conclusions: Taken together, our results suggest that umbelliferone 6-carboxylic acid, esculetin and daphnetin have anti-AD effects by inhibiting AChE, BChE and BACE1, which might be useful against AD.
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Objective To improve the quality standard ofZushima Plaster.Methods TLC was used to do qualitative identification of daphnetin and 7-hydroxycoumarin inZushima Plaster. The contents of daphnetin and 7-hydroxycoumarin inZushima Plaster were determined by HPLC. The chromatographic column was Agilent Eclipse Plus C18 (4.6 mm×250 mm, 5μm), and the mobile phase consisted of acetonitrile-0.1% phosphoric asid (15∶85, V/V) at a flow rate of 1.0 mL/min. The column temperature was maintained at 30℃, and the detection wavelength was set at 327 nm. Results Characteristic spots of daphnetin and 7-hydroxycoumarin could be detected by TLC from the samples, and the spots were clear and specific without interference from negative samples. The calibration curve of daphnetin and 7-hydroxycoumarin were linear in the ranges of 0.180-1.800μg and 0.100-1.00μg (r=0.999 1,r=0.999 2), and the average recovery rates were 98.99% and 101.48%, RSDwere1.43% and 1.32%, respectively (n=9).Conclusion The established method appears easy to use, accurate and specific, and therefore can be used for the quality control ofZushima Plaster.
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Objective To optimize the extraction process of Zushima Gel Cream.Methods Setting the content of daphnetin as an investigating index, and the amount of solvent, soak time and the extraction time as investigating factors, the orthogonal experiment was used to optimize the extraction process.Results The best extraction process was as follows:adding 30 mL water to degreasing Zushima Gel Cream;soaking for half an hour;extracting one time for two hours. The average content of daphnetin was 9.83 mg/g.Conclusion The extraction process is stable, reliable, and energy-saving. The study provided experimental evidence for the preparation process of Zushima Gel Cream.
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OBJECTIVE: To study the chemical constituents in Ainsliaea bonatii. METHODS: The column chromatographic techniques were used to isolate the constituents in A. bonatii. EI-MS and NMR were used to identify the constituents structures. RESULTS: Seven compounds were isolated and identified from the extract of A. bonatii, whose structures were elucidated as taraxasterol (1), β-sitosterol (2), nodakenetin (3), 1, 4-benzenediol (4), daphnetin (5), apigenin (6) and β-arbutin (7). CONCLUSION: Compounds 1-5 and 7were isolated for the first time from this plant, and 1, 3-5 were isolated for the first time from Ainsliaea genus.
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Six coumarins daphnin (1), daphnetin (2), daphnetin glucoside (3), rhodonetin (4), rhodonin (5) and umbelliferone (6) were isolated from the methanolic extract of Rhododendron lepidotum Wall. ex G. Don, Ericaceae (aerial part). The compounds and their acetyl derivatives were screened for antibacterial activity against Staphylococcus aureus ATCC-29213, methicillin resistant Staphylococcus aureus ATCC-15187, Escherichia coli ATCC-8739, Pseudomonas aeruginosa ATCC-9027 by microdilution method as compared to the reference ciprofloxacin. Compound 2 displayed the best antibacterial activity with MIC 125 μg/mL against S. aureus ATCC-29213 and MRSA ATCC-15187 followed by 4 which exhibited the MIC value of 250 μg/mL against all the four tested strains. All molecules showed better antibacterial activity than their acyl derivatives.
Seis cumarinas dafinina (1), dafinetina (2), dafinetina glicosídeo (3), rodonetina (4), rodonina (5) e umbeliferona (6) foram isoladas do extrato metanólico das partes aéreas de Rhododendron lepidotum Wall. ex G. Don, Ericaceae. Os compostos e seus derivados acetilados foram testados para verificar sua atividade antibacteriana contra Staphylococcus aureus ATCC-29213, Escherichia coli resistente à meticilina, Staphylococcus aureus ATCC-15187, ATCC-8739, Pseudomonas aeruginosa ATCC-9027, pelo método de microdiluição, usando ciprofloxacina como referência. A substância 2 apresentou a melhor atividade antibacteriana com o MIC 125 μg/mL contra S. aureus ATCC-29213 e MRSA ATCC-15187 seguido pela substância 4, que apresentou o valor de CIM de 250 μg/mL contra as quatro cepas testadas. Todas as moléculas apresentaram melhor atividade antibacteriana do que seus derivados acetilados.
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Objective To establish a HPLC method for the determination of daphnetin, 7-OH coumarin and syringing in Zushima. Methods The separation was performed on YMC-Pack ODS (4.6 mm?250 mm, 5 ?m) column with a mobile phase consisting of methanol-0.5% acetic acid-water (19︰8︰1) as gradient elution at the flow rate of 1.0 mL/min. The dual detective wavelength was set at 327 nm and 266 nm. The column temperature was 30 ℃. Results Baseline separation was achieved for the analysis of the three index components. The average recoveries were 98.4%～100.2%. Conclusion This method is convenient, rapid and accurate. It can be used for quality control in production of Zushima.
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OBJECTIVE:To establish an HPLC method of the determination of dapchnetin in Qufeng xitong plaster. METHODS:The sample was determined on Sinochrom ODS-BP(250 mm?4.6 mm,5 ?m) column.The mobile phase consisted of acetonitrile-0.2% phosphoric acid(14∶86) at a flow rate of 1.0 mL?min-1.The detection wavelength was set at 327 nm and the sample size was 20 ?L.RESULTS:The calibration curve of daphnetin was linear over the concentration range of 20～120 ?g?mL-1(r=0.999 6).The average recovery was 99.36%(RSD=0.70%,n=6).CONCLUSION:The method was proved to be simple,rapid,accurate with satisfactory recovery rate,and it can be used for the quality control of Qufeng xitong plaster.
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Objective To investigate the therapeutic effect of a combination of artemether and daphnetin against Plasmodium berghei ANKA strain in mice. Methods Groups of P. berghei infected mice were treated with various oral doses of artemether and daphnetin according to “4-day suppress assay”. Thin blood smears were made on the fifth day after inoculation of parasites and the parasitemia reduction rate was calculated. The ED 50 values obtained were plotted on isobolograms. A combined action of artemether and daphnetin was assessed. Results Artemether 0.4mg/(kg?d)?4d exhibited no detectable antimalarial effect, while artemether 0.4mg/(kg?d)?4d combined with daphnetin 7.7 mg/kg.d?4d showed potent antiparasile efficacy. The ED 50s of artemether in combination with daphnetin were lower than that of single artemether or daphnetin. The R-values were higher than 0.4, but lower than 2.7. Conclusion The combination of artemether with daphnetin showed an additive antiparasile effect.
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Objective To investigate the effect of daphnetin on superoxide dismutase (SOD) activity and DNA synthesis in P. falciparum in vitro. Methods The effect of daphnetin, daphnetin-Fe complex and desferrioxamine B on SOD activity of P. falciparum (P. f) FOCI in vitro was determined with a SOD test-kit. The level of DNA synthesis of P. f synchronized cultured in vitro at various developmental stages after treatment of daphnetin or desferrioxamine B was assayed by fluorescein Hoechest 33258. Results The total SOD activity decreased by 60% after daphnetin treatment while it only decreased by 22% if treated with desferrioxamine B. No effect on SOD activity of P. f treated with daphnetin-Fe complex was observed. The level of DNA synthesis of P. f trophozoites in synchronized in vitro culture was significantly lower than that of the control. Conclusion Daphnetin lowered SOD activity and decreased DNA synthesis of P. f in vitro.