Neuroprotective effects of scutellarin on rat neuronal damage induced by cerebral ischemia/reperfusion.
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AIM: To investigate the neuroprotective effect and mechanisms of scutellarin, a flavonoid extracted from Erigeron breviscapus Hand Mazz, against neuronal damage following cerebral ischemia/reperfusion. METHODS: Rats were pretreated ig with scutellarin for 7 d and then subjected to cerebral ischemia/reperfusion (I/R) injury induced by a middle cerebral artery occlusion (MCAO). The infarct volume and neurological deficit were determined by TTC staining and Longa's score. The permeability of the blood-brain barrier was evaluated by measurement of the Evans blue (EB) content in the brain with a spectrophotometer. The total NOx content was determined. Nitric oxide synthase (NOS) isoforms (iNOS, eNOS, nNOS) and the key angiogenic molecules, vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF), were detected by Western blotting. RESULTS: Scutellarin significantly reduced infarct volume (P<0.05 or P<0.01), ameliorated the neurological deficit and reduced the permeability of the blood-brain barrier (BBB) (P<0.05). When rats were pretreated with scutellarin (50 or 75 mg/kg), upregulation of eNOS expression and downregulation of VEGF, bFGF, and iNOS expression was observed, whereas scutellarin had no effect on nNOS expression. CONCLUSION: Scutellarin has protective effects for cerebral injury through regulating the expression of NOS isoforms and angiogenic molecules. (+info)
Mendelian segregation for two-factor apomixis in Erigeron annuus (Asteraceae).
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The inheritance of asexual seed development (apomixis) in Erigeron annuus (Asteraceae) was evaluated in a triploid (2n=3x=27) population resulting from a cross between an apomictic tetraploid (2n=4x=36) pollen parent and a sexual diploid (2n=2x=18) seed parent. Diplospory (unreduced female gametophyte formation) and autonomous development (embryo and endosperm together) segregated independently in the population yielding four distinct phenotype classes: (1) apomictic plants combining diplospory and autonomous development, (2) diplosporous plants lacking autonomous development, (3) meiotic plants with autonomous (though abortive) development and (4) meiotic plants lacking autonomous development. Each class was represented by approximately one-quarter of the population (n=117), thus corresponding to a two-factor genetic model with no linkage (chi(2)=2.59, P=0.11). Observations demonstrate that autonomous embryo and endosperm development (jointly) may occur in either reduced or unreduced egg cells. The cosegregation of the traits is attributed to tight linkage or pleiotropy. The data are consistent with the hypothesis that autonomous development in E. annuus is regulated by a single fertilization factor, F, which initiates development of both the embryo and the endosperm in the absence of fertilization. (+info)
Flavonoid aglycones and phytosterols from the Erigeron acris L. herb.
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Four flavonoid aglycones (apigenin, kaempferol, luteolin, quercetin) were isolated from methanolic extract from the herb of Erigemn acris L. (Asteraceae). In this extract five phytosterols (campesterol, chondrillasterol, stigmast-7-en-3-ol(5alpha,3alpha), stigmasterol and spinasterone) were also identified. (+info)
Effects of scutellarin on PKCgamma in PC12 cell injury induced by oxygen and glucose deprivation.
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AIM: To evaluate the neuroprotective effect and mechanisms of scutellarin (Scu) against PC12 cell injury after oxygen and glucose deprivation followed by reperfusion (OGD-Rep). METHODS: Undifferentiated rat pheochromocytoma PC12 cells, exposed to oxygen and glucose deprivation followed by reperfusion (OGD-Rep), used as an in vitro model of ischemia/reperfusion. Cell survival was evaluated by diphenyltetrazolium bromide (MTT) assay and the amount of LDH release was determined using assay kits. [Ca2+](i) was monitored using a fluorescent Ca2+-sensitive dye Fura-2 acetoxymethyl ester. Cell apoptosis was detected by a DNA ladder and by flow cytometric detection. The expression of protein kinase C (PKC)gamma was determined using both RT-PCR and Western blotting. The translocation of PKCgamma was assayed by subcellular fractionation and Western blotting. RESULTS: OGD-Rep injury significantly elevated the level of LDH release, [Ca2+](i), mRNA expression and the translocation of PKCgamma compared in the PC12 cells with those of the normal group. Scu (10-100 micromol/L) exerted a protective effect against OGD-Rep injury by reducing LDH release, [Ca2+](i), the percent of apoptosis, and the translocation of PKCgamma. CONCLUSION: Scu inhibits the increase of [Ca2+](i) and the activation of PKCgamma, exerting protective effects against PC12 cell injury induced by OGD-Rep. (+info)
Comparison of the antiinflammatory activities of three medicinal plants known as "meiduoluomi" in Tibetan folk medicine.
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Erigeron breviscapus (Vant.) Hand-mazz (EB), Erigeron multiradiatus (Lindl.) Benth (EM), and Aster brachytrichus Franch (AB), confused under the vernacular name "meiduoluomi" by native people and traditional healers, have been used for the treatment of meningitis, polyneuritis, hepatitis, adenolymphitis, and enteronitis in traditional Tibetan medicine. In this study, the antiinflammatory activity of methanol extracts of all three plants was investigated in the xylene-induced ear edema model, carrageenan-induced paw edema model, and cotton pellet-induced granuloma model. It was found that the methanolic extracts of both EB and EM had strong inhibitory effects on the acute phase of inflammation in carrageenan-induced paw edema in rats. On the other hand, the methanolic extract of EM showed stronger effects than those of EB in xylene-induced ear edema. In the chronic test, the methanolic extracts of EB and EM resulted in a significant reduction in granuloma weight in rats. In addition, myeloperoxidase (MPO) activity was strongly reduced in the EB-treated and EM-treated groups, which indicated that EB and EM can inhibit certain inflammatory modulator factors that cause neutrophil aggregation in inflamed tissue, e.g., nuclear factor-kappaB. However, the methanolic extracts of AB had no antiinflammatory effects in the tested models and MPO assay. The similar effects of EM and EB in tested models provided some scientific basis for the traditional usage of meiduoluomi in inflammatory disease. However, the results also suggest that further study is needed to investigate the antiinflammatory profile of AB and provide a scientific basis for the use of AB in inflammatory diseases. (+info)
Scutellarin isolated from Erigeron multiradiatus inhibits high glucose-mediated vascular inflammation.
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Erigeron multiradiatus (Lindl.) Benth is a traditional Tibetan medicine herb long used to treat various diseases related to inflammation. Our previous phytochemical studies on E. multiradiatus resulted in the isolation of scutellarin, which is a known flavone glucuronide with comprehensive pharmacological actions. In present study, we investigated the inhibition action of scutellarin on high glucose-induced vascular inflammation in human endothelial cells (ECV304 cells). Consistent with previous reports, exposure of ECV304 cells to high glucose for 24 h caused an increase of intercellular adhesion molecule-1 (ICAM-1) and monocyte chemoattractant protein 1 (MCP-1), and promoted cell adhesion between monocyte and ECV304 cells. However, pretreatment with scutellarin (0.1 and 1 microM) reversed these effects in a concentration-dependent manner. Scutellarin was able to inhibit the activation of NF-kappaB induced by high glucose in ECV304 cells. Furthermore, although oral administration of scutellarin (10 and 50 mg/kg) did not produce significant antihyperglycemic action, it lowered the serum MCP-1 levels significantly in alloxan-induced diabetic mice. Therefore, our results suggest that scutellarin has anti-inflammation effect that may afford some protection against hyperglycemia-induced vascular inflammatory both in vitro and in vivo. (+info)
Depigmentation of melanocytes by (2Z,8Z)-matricaria acid methyl ester isolated from Erigeron breviscapus.
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To discover an active skin depigmenting agent, we isolated a novel inhibitor of melanin biosynthesis from the methanol extract of Erigeron breviscapus using a bioactivity-guided fractionation and identified it as (2Z,8Z)-matricaria acid methyl ester by means of spectroscopic analysis. The compound showed strong whitening activity in melan-a cell. Compared with arbutin (IC(50)=4.0 mM) as a positive control, the depigmentation IC(50) value for (2Z,8Z)-matricaria acid methyl ester was 25.4 muM in B16F10 melanoma cell. Moreover, its inhibitory effect on tyrosinase, the key enzyme of melanogenesis, was examined by in vivo and in vitro tyrosinase assay and Western blot. The results indicate that (2Z,8Z)-matricaria acid methyl ester isolated from Erigeron breviscapus is a promising compound that could be useful for treating hyper-pigmentation as skin-whitening agents. (+info)
Chemical composition of the essential oils from the roots of Erigeron acris L. and Erigeron annuus (L.) Pers.
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