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21.
Background: Interstitial cystitis is characterized by over 6 months of chronic pain, pressure and discomfort felt in the lower pelvis or bladder. It is often relieved with voiding, along with daytime frequency and nocturia in the absence of a urinary tract infection. Interstitial cystitis occurs primarily in females including adolescents and its diagnosis is still one of exclusion. It is now recognized as a serious medical condition associated with significant disability. Objective: The aim of this paper was to review the pathogenesis and treatment of interstitial cystitis with emphasis on new pathogenetic trends and therapeutic modalities. Methods: About 713 mostly original papers were reviewed in Medline from 1990 to August. 2008. All authors independently reviewed the literature. Large, double-blind, placebo-controlled, clinical trials were few and the medical histories of the patients used varied considerably making conclusions difficult. Promising pilot trials turned out mostly negative on follow-up. Results: Increasing evidence of co-morbid diseases, neurogenic inflammation and the effect of stress are promising as new targets for pathophysiology. No new effective treatments have emerged. Oral pentosanpolysulfate, amitriptyline, hydroxyzine and quercetin, as well as intravesical heparin/bicarbonate/lidocaine solutions, are still used with variable success. Some pilot open-label trials presented encouraging findings. Conclusion: Interstitial cystitis contributes substantially to chronic pelvic pain and to poor quality of life. Oral or intravesical administration of solutions containing sodium hyaluronate, chondroitin sulfate and quercetin to both reduce bladder inflammation and ‘replenish’ the glycosaminoglycan layer should be tried. There is a clear need for therapeutic modalities. New potential translational research areas are suggested.  相似文献   
22.
Objective:To investigate the effects of quercetin on Hedgehog(Hh) signaling in chronic myeloid leukemia KBM7 cells.Methods:The KBM7 cells were treated with 50,100 and 200 μmol/L quercetin for48 h respectively.And then the trypan blue assay was used to examine the proliferative inhibition of quercetin.Apoptotic cells and cell cycle were measured by flow cytometry.The mRNA and protein expression were detected by quantitative real-time polymerase chain reaction(PCR) and Western blot,respectively.Results:Quercetin significantly inhibited KBM7 cell proliferation,induced cell apoptosis,and blocked cell cycle at G1 phase,which were in dose-dependent manners.The mRNA and protein expression of Smoothened and Gliomal(Gli1),the members of Hh pathway decreased after treatment with quercetin.The Bcl-2 and Cyclin D1,targets of Hh signaling,also decreased after treatment with quercetin,respectively.Quercetin also could increase p53 and Caspase-3 expression.Bcr-abl mRNA copies decreased,but no changes of phosphorylated Bcr-abl and Bcr-abl proteins were observed,after treatment with quercetin.Conclusion:Quercetin could inhibit Hh signaling and its downstream targets in the KBM7 cells.And it might be one of mechanisms of inducing apoptosis and inhibiting cell cycle by quercetin.  相似文献   
23.
Objective To study the ent-kaurane diterpenoids from Rabdosia rubescens. Methods The compounds were isolated by chromatographies and their structures were identified by spectral analyses. Results Four compounds were isolated, and they were identified as bisrubescensin E (1), 2α,3α,24-trihydroxyurs-12-en-28-oic acid (2), 2α,3α,24-trihydroxyurs-12,20-(30)-dien-28-oic acid (3), and 6,7-dihydroxycoumarin (4). Conclusion Compound 1 is a new asymmetric ent-kauranoid dimer. Compound 2 is isolated from the plant for the first time. Compounds 3 and 4 are isolated from the plants of Rabdosia (Bl.) Hassk for the first time.  相似文献   
24.
The main objective of our present work was to ascertain the efficacy of Drosophila melanogaster model for assessing antigenotoxic and antioxidant effects of dietary phytochemicals gallic acid (GA), quercetin (QC) and limonene (Lim) against urethane (URE), a genotoxic environmental carcinogen. Oregon-K (ORK) adult male flies were fed GA, QC and Lim in combination with URE (20?mM) in 10% sucrose for 72?h. Third instar larvae were fed instant medium containing the above phytochemicals and URE for 24?h. Sex-linked recessive lethal (SLRL) test and assays for estimating glutathione content (GSH), glutathione S-transferase (GST), catalase (CAT), superoxide dismutase (SOD) and lipid peroxidation (MDA content) were performed. Adult feeding experiments demonstrated that co-treatment of flies with URE and the test phytochemicals has significantly decreased the frequencies of SLRL mutations in all the germ cell stages when compared to that with URE alone. Larval feeding experiments also showed a similar pattern. The above results correlate well with antioxidative potentials of the test agents where we observed the elevated enzymatic levels with a significant reduction in MDA level in Drosophila larvae. The results further suggest that the dietary phytochemicals have an antioxidant and antimutagenic property which can be assessed using D. melanogaster.  相似文献   
25.
The rutin, quercetin concentrations, antioxidant activity, and aroma compounds in different commercial tartary buckwheat tea were analyzed in our study. Results revealed that the materials and the processing protocol affected the chemical composition and activity of tartary buckwheat tea. Rutin and quercetin concentrations, antioxidant activity were significantly different in various kinds of tartary buckwheat tea, where the whole bran tea and the whole plant tea had the lower rutin, but higher quercetin concentrations and higher antioxidant activity. The whole embryo tea had the converse results. There was strong correlation between quercetin concentration and antioxidant activity (r>0.98, P<0.05). Meanwhile, Twenty eight different aroma compounds in tartary buckwheat tea were identified by gas chromatography-mass spectrometry. Those compounds were mainly composed of pyrazine, aldehydes, fatty acids and ketones. The main type of aroma compounds in different tartary buckwheat tea were similar, but their relative contents were different. The implications to the quality control of buckwheat tea were extensively discussed.  相似文献   
26.
刘静  郭欣  黄娜娜  吴恺怿  孙蓉 《中草药》2019,50(21):5145-5153
目的运用网络药理学分析方法,明确柴胡桂枝干姜汤治疗失眠的作用机制。方法运用TCMSP、TCMID数据库锁定柴胡桂枝干姜汤7味药的药物靶标,TTD、DrugBank、PubMed数据库查找失眠的疾病靶点,构建"疾病-方剂-靶点"网络,用STRING和Cytoscape分析软件对其关键靶点进行富集分析,明确作用机制。结果柴胡桂枝干姜汤蛋白质-蛋白质相互作用(PPI)网络包含靶标640个,失眠的PPI网络包括靶标175个,富集分析得29个关键靶标和其间80条互作关系;GO富集分析及KEGG途径分析结果显示柴胡桂枝干姜汤中柴胡皂苷a、柴胡皂苷d、槲皮素、碳酸钙、6-姜辣醇、山柰酚、汉黄芩素等171个活性成分主要通过CACNA1C、GABRA1、GABRA2、GABRB3、GABRA3等29个关键靶标及突触信号传导、膜电位的调节、G蛋白偶联受体信号通路等生物过程,神经递质受体活性、离子门控通道活动、GABA-A受体活性等分子功能,质膜、突触等细胞组成作用于神经活性配体-受体相互作用、逆行内源性大麻素信号传导、5-羟色胺能突触等多条作用通路发挥治疗失眠作用。结论柴胡皂苷a、柴胡皂苷d等171个活性成分是柴胡桂枝干姜汤治疗失眠的药效物质基础,神经活性配体-受体相互作用等通路和CACNA1C等29个靶标构成了其发挥"疏肝健脾、调和阴阳"的功效作用网络,为临床合理运用柴胡桂枝干姜汤治疗失眠提供了网络药理学证据。  相似文献   
27.
The plant melatonin biosynthetic pathway has been well characterized, but inhibitors of melatonin synthesis have not been well studied. Here, we found that flavonoids potently inhibited plant melatonin synthesis. For example, flavonoids including morin and myricetin significantly inhibited purified, recombinant sheep serotonin N‐acetyltransferase (SNAT). Flavonoids also dose‐dependently and potently inhibited purified rice SNAT1 and SNAT2. Thus, myricetin (100 μmol/L) reduced rice SNAT1 and SNAT2 activity 7‐ and 10‐fold, respectively, and also strongly inhibited the N‐acetylserotonin methyltransferase activity of purified, recombinant rice caffeic acid O‐methyltransferase. To explore the in vivo effects, rice leaves were treated with flavonoids and then cadmium. Flavonoid‐treated leaves had lower melatonin levels than the untreated control. To explore the direct roles of flavonoids in melatonin biosynthesis, we first functionally characterized a putative rice flavonol synthase (FLS) in vitro and generated flavonoid‐rich transgenic rice plants that overexpressed FLS. Such plants produced more flavonoids but less melatonin than the wild‐type, which suggests that flavonoids indeed inhibit plant melatonin biosynthesis.  相似文献   
28.
《中国神经再生研究》2016,(8):1247-1253
The neuroprotective property of quercetin is well reported against hypoxia and ischemia in past studies.This property of quercetin lies in its antioxidant property with blood-brain barrier permeability and anti-inflammatory capabilities.μ-Calpain,a calcium ion activated intracellular cysteine protease causes serious cellular insult,leading to cell death in various pathological conditions including hypoxia and ischemic stroke.Hence,it may be considered as a potential drug target for the treatment of hypoxia induced neuronal injury.As the inhibitory property of μ-calpain is yet to be explored in details,hence,in the present study,we investigated the interaction of quercetin with μ-calpain through a molecular dynamics simulation study as a tool through clarifying the molecular mechanism of such inhibition and determining the probable sites and modes of quercetin interaction with the μ-calpain catalytic domain.In addition,we also investigated the structure-activity relationship of quercetin with μ-calpain.Affinity binding of quercetin with μ-calpain had a value of –28.73 k J/mol and a Ki value of 35.87 μM that may be a probable reason to lead to altered functioning of μ-calpain.Hence,quercetin was found to be an inhibitor of μ-calpain which might have a possible therapeutic role in hypoxic injury.  相似文献   
29.
The aim of this study is to investigate the effects of the quercetin (Q) and chrysin (CH) on oxidative stress, cytokines levels and body weights in rats induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Rats were divided randomly into six equal groups. TCDD, Q and CH were administered by gavages dissolved in corn oil at the doses of 2 µg/kg/week, 20?mg/kg/day and 50?mg/kg/day, respectively. The blood samples were taken from all rats at 60th days to be analyzed for the determination of thiobarbituric acid reactive substances (TBARS), tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ). The results indicated that although TCDD increased significantly TBARS and TNF-α levels, it caused a decline in the levels of IFN-γ and body weight. In contrast, these effects of TCDD on TBARS, TNF-α, IFN-γ levels and body weight were significantly prevented by treatments of Q and CH. In conclusion, it was determined that TCDD caused the adverse effects on immune functions, body weight and oxidative stress in rats. However, Q and CH administered with TCDD eliminated these adverse effects. These results suggest that Q and CH may play a protective role against TCDD toxicity.  相似文献   
30.
As biocompatible matrices, porcine dermal scaffolds have limited application in tissue engineering due to rapid degradation following implantation. This study compared the physical, chemical and biomechanical changes that occurred when genipin and quercetin were used to crosslink dermal scaffolds and to determine whether quercetin could be used as an alternative to genipin. Physicochemical changes in the collagen were assessed using spectroscopic methods [X‐ray diffraction analysis (XRD) and nuclear magnetic resonance (NMR) analysis]. The crosslinking reaction was evaluated by quantification of amino acids and the degree of this reaction by ninhydrin assay. Because the mechanical behaviour of the collagen matrices is highly influenced by crosslinking, the tensile strength of both sets of scaffolds was evaluated. The highest mechanical strength, stiffness, degree of crosslinking and changes in the packing features of collagen (measured by XRD) were achieved using genipin. Some of the results found in the quercetin‐crosslinked scaffolds were possibly due to hydration and dehydration effects elicited by the solvents (phosphate‐buffered saline or ethanol), as seen in the NMR results. In the quercetin‐ethanol‐crosslinked scaffolds, possible reorientation of the amino groups of the collagen molecule may have taken place. Therefore, depending on their proximity to the crosslinking reagent, different types and numbers of interactions may have occurred, inducing a higher crosslinking degree (as evidenced by the ninhydrin assay) and reduction in the free amino acids after reaction. Both crosslinking agents and solvents interfere in the physicochemical properties of collagen thereby inducing variations in the matrix structure. Quercetin‐crosslinked scaffolds may have broader clinical application where a lower degree of crosslinking and stiffness is required. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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