Chemical composition,antioxidant activity and hepatoprotective potential of Rourea induta Planch. (Connaraceae) against CCl4-induced liver injury in female rats

ObjectivesThe aim of this study was to evaluate the flavonoid content of an ethanolic leaf extract from the medicinal plant Rourea induta Planch. (RIEE) and to investigate its hepatoprotective potential and in vivo antioxidant effects.MethodsUsing samples from carbon tetrachloride-treated Wistar female rats treated orally with or without RIEE, we evaluated the aspartate aminotransferase, alanine aminotransferase, and total bilirubin levels in plasma; the levels of the hepatic oxidative stress markers catalase, superoxide dismutase, glutathione peroxidase, and reduced glutathione in liver homogenates; and the thiobarbituric acid reactive substance levels. A histopathology study was performed. A quantitative analysis of the RIEE extract was performed using high-performance liquid chromatography to evaluate its flavonoid content.ResultsOral administration of RIEE significantly reduced carbon tetrachloride-induced elevations in the levels of plasma markers of hepatic damage and lipid peroxidation. It also rescued histopathologic alterations observed in the liver and levels of oxidative stress markers.ConclusionsRIEE exhibits antioxidant and hepatoprotective activities in vivo, which may be attributable to its flavonoids composition [hyperin (2), quercetin-3-O-β-xyloside (4), quercetin-3-O-α-arabinofuranoside (5), and quercetin (6)].     

Comparative effects of catechin,epicatechin and N-Ω-nitroarginine on quinolinic acid-induced oxidative stress in rat striatum slices

The aim of this work was to compare the effects of catechin (CAT), epicatechin (EPI) and N-ω-l-nitroarginine (L-NARG) on different endpoints of oxidative stress induced by quinolinic acid (QUIN) in a simple tissue preparation, rat striatal slices – with particular emphasis in the glutathione system – in order to provide revealing information on the antioxidant efficacy of these agents in an excitotoxic model.MethodsRat striatal slices were incubated for 1 h in the presence of 100 μM QUIN and/or 85 μM CAT or EPI, or 100 μM L-NARG. Lipid peroxidation (LP) and the levels of reduced and oxidized glutathione (GSH and GSSG) were determined.ResultsThe three agents tested completely blocked the QUIN-induced lipid peroxidation and recovered the QUIN-induced altered GSH/GSSG balance. No statistical differences were detected among the protective effects exerted by these antioxidants, suggesting similar efficacy and common antioxidant mechanisms. The antioxidant properties exhibited by these molecules on the excitotoxic model tested herein support an active role of glutathione and prompt their use as therapeutic tools in models of neurodegenerative disorders.     

Flavanols are potential anti-obesity agents,a systematic review and meta-analysis of controlled clinical trials

Background

The anti-obesity potential of flavonoids has been shown by animal and human studies. In this meta-analysis, we systematically reviewed controlled clinical trials and quantified the effects of flavonoids and flavonoid subclasses on obesity-related anthropometric measures.

Quercetin regulates oxidized LDL induced inflammatory changes in human PBMCs by modulating the TLR-NF-κB signaling pathway

Toll-like receptors (TLRs) have been shown to play a pivotal role in both innate and adaptive immune responses. TLR family is the essential recognition and signaling component of mammalian host defense. Both genetic and biochemical data support a common signaling pathway that finally leads to the activation of NF-κB and induction of the cytokines and co-stimulatory molecules required for the activation of the adaptive immune response. The present study was designed to examine the involvement of TLR2 and TLR4 in the oxidized LDL induced inflammation in human PBMCs and the effect of flavonoid quercetin on TLR-NF-κB signaling mechanism. LDL was isolated from human plasma and oxidation of LDL was done by incubating with 10 μM CuSO₄ overnight at 37 °C. The isolated human PBMCs in culture were used as the model system. 50 μg/ml ox-LDL treatment significantly up regulated TLR2 and TLR4 expression in isol human PBMCs after 24 h of culture and this was down regulated by quercetin at 25 μM concentration. ox-LDL caused a significant activation of NF-κB as evidenced by the detection of enhanced p65 subunit in nuclear extracts. Supplementation of quercetin significantly modulates the NF-κB p65 nuclear translocation. The cytokine IL-6 production was significantly increased in ox-LDL treated group and was decreased by quercetin treatment. Quercetin mediated reduction of TLR2 and TLR4 expression and the inhibition of nuclear translocation of NF-κB p65 in turn decreased the inflammatory enzymes like 5-LOX and COX and also decreased the mRNA expression of inducible enzymes like COX-2 and iNOS. Quercetin inhibited the ox-LDL induced TLR2 and TLR4 expression at mRNA level and modulated the TLR-NF-κB signaling pathway thereby inhibited the cytokine production and down regulated the activity of inflammatory enzymes thus have protective effect against the ox-LDL induced inflammation in PBMCs.     

玉郎伞提取物平喘镇咳作用的研究

目的研究玉郎伞水提物及从玉郎伞中提取的3种活性成份-黄酮、皂苷、多糖的平喘镇咳作用。方法采用豚鼠喷雾致喘法、小鼠氨水引咳法,观察玉郎伞水提物及3种成份对豚鼠引喘潜伏期、小鼠咳嗽潜伏期的影响。结果玉郎伞水提物及3种成份能显著延长乙酰胆碱组胺混合刺激所致豚鼠哮喘的引喘潜伏期,减少氨水致小鼠的咳嗽次数并延长咳嗽潜伏期。结论玉郎伞水提物及3种活性成份具有较强的平喘镇咳作用。     

正交试验法优选桃红四物汤醇提工艺

目的：优选桃红四物汤的醇提工艺。方法：以总黄酮含量和浸膏得率为考察指标,以乙醇浓度、乙醇用量、提取时间、提取次数为考察因素,采用正交试验优选桃红四物汤的最佳醇提工艺。结果：桃红四物汤的最佳醇提工艺为加6倍量80％乙醇提取三次,每次1．5h。结论：优选出的桃红四物汤的醇提工艺合理、稳定,可为其工业化生产提供参考。     

Prospective cohort comparison of flavonoid treatment in patients with resected colorectal cancer to prevent recurrence

AIM： To investigate biological prevention with flavonoids the recurrence risk of neoplasia was studied in patients with resected colorectal cancer and after adenoma polypectomy. METHODS： Eighty-seven patients, 36 patients with resected colon cancer and 51 patients after polypectomy, were divided into 2 groups： one group was treated with a flavonoid mixture （daily standard dose 20 mg apigenin and 20 mg epigallocathechin-gallat, n = 31） and compared with a matched control group （n = 56）. Both groups were observed for 3-4 years by surveillance colonoscopy and by questionnaire. RESULTS： Of 87 patients enrolled in this study, 36 had resected colon cancer and 29 of these patients had surveillance colonoscopy. Among the flavonoid-treated patients with resected colon cancer （n = 14）, there was no cancer recurrence and one adenoma developed. In contrast the cancer recurrence rate of the 15 matched untreated controls was 20% （3 of 15） and adenomas evolved in 4 of those patients （27%）. The combined recurrence rate for neoplasia was 7% （1 of 14） in the treated patients and 47% （7 of 15） in the controls （P = 0.027）. CONCLUSION： Sustained long-term treatment with a flavonoid mixture could reduce the recurrence rate of colon neoplasia in patients with resected colon cancer.     

An oxepinoflavone from <Emphasis Type="Italic">Artocarpus elasticus</Emphasis> with cytotoxic activity against P-388 cells

A new oxepinoflavone, artoindonesianin E1 (1), was isolated from the wood of Artocarpus elasticus, along with four known prenylated flavones: artocarpin (2), cycloartocarpin (3), cudraflavones A (4) and C (5). The structure of the new compound was identified by spectroscopic methods. Upon cytotoxic evaluation against murine leukemia P-388 cells, the new compound showed IC₅₀ 5.0 μg/mL.     

Protective effects of proanthocyanidins of grape (Vitis vinifera L.) seeds on DNA damage induced by Doxorubicin in somatic cells of Drosophila melanogaster

Proanthocyanidins (PAs), also known as condensed tannins, are naturally occurring oligomers and polymers of flavan-3-ol monomer units widely found in the leaves, flowers, fruits, seeds, nuts and barks of many plants. Grape seed proanthocyanidins (GSPs) have been used as nutritional supplements, as antioxidants, in preventing atherosclerosis and cardiovascular diseases, and for dislipidemy treatment. The anthracycline antibiotic adriamycin (Doxorubicin, DXR) is a cancer chemotherapeutic agent that interferes with the topoisomerase II enzyme and generates free radicals. In the present study, GSPs (1.680, 3.375, or 6.750 mg/mL) alone were examined for genotoxicity, and combined with DXR (0.125 mg/mL) for antigenotoxicity, using the standard (ST) and high bioactivation (HB) versions of the wing somatic mutation and recombination test in Drosophila melanogaster. The results observed in both crosses were rather similar. GSPs themselves did not show genotoxicity at the doses used. GSPs suppressed the DNA damage induced by DXR in a dose-dependent manner. Comparison of the frequencies of wing spots in the marker-heterozygous (MH) flies and balancer-heterozygous (BH) flies from both crosses, indicated that induced recombination was the major response for the treatments with DXR alone. The co-treatments demonstrated that GSPs have some anti-mutagenic activity; however, anti-recombinagenic activity was the major response.