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Sample records for quercetin cancer cell-specific

  1. FOXA1 defines cancer cell specificity

    PubMed Central

    Zhang, Gaihua; Zhao, Yongbing; Liu, Yi; Kao, Li-Pin; Wang, Xiao; Skerry, Benjamin; Li, Zhaoyu

    2016-01-01

    A transcription factor functions differentially and/or identically in multiple cell types. However, the mechanism for cell-specific regulation of a transcription factor remains to be elucidated. We address how a single transcription factor, forkhead box protein A1 (FOXA1), forms cell-specific genomic signatures and differentially regulates gene expression in four human cancer cell lines (HepG2, LNCaP, MCF7, and T47D). FOXA1 is a pioneer transcription factor in organogenesis and cancer progression. Genomewide mapping of FOXA1 by chromatin immunoprecipitation sequencing annotates that target genes associated with FOXA1 binding are mostly common to these cancer cells. However, most of the functional FOXA1 target genes are specific to each cancer cell type. Further investigations using CRISPR-Cas9 genome editing technology indicate that cell-specific FOXA1 regulation is attributable to unique FOXA1 binding, genetic variations, and/or potential epigenetic regulation. Thus, FOXA1 controls the specificity of cancer cell types. We raise a “flower-blooming” hypothesis for cell-specific transcriptional regulation based on these observations. PMID:27034986

  2. Quercetin: a pleiotropic kinase inhibitor against cancer.

    PubMed

    Russo, Gian Luigi; Russo, Maria; Spagnuolo, Carmela; Tedesco, Idolo; Bilotto, Stefania; Iannitti, Roberta; Palumbo, Rosanna

    2014-01-01

    Increased consumption of fruits and vegetables can represent an easy strategy to significantly reduce the incidence of cancer. From this observation, derived mostly from epidemiological data, the new field of chemoprevention has emerged in the primary and secondary prevention of cancer. Chemoprevention is defined as the use of natural or synthetic compounds able to stop, reverse, or delay the process of tumorigenesis in its early stages. A large number of phytochemicals are potentially capable of simultaneously inhibiting and modulating several key factors regulating cell proliferation in cancer cells. Quercetin is a flavonoid possessing potential chemopreventive properties. It is a functionally pleiotropic molecule, possessing multiple intracellular targets, affecting different cell signaling processes usually altered in cancer cells, with limited toxicity on normal cells. Simultaneously targeting multiple pathways may help to kill malignant cells and slow down the onset of drug resistance. Among the different substrates triggered by quercetin, we have reviewed the ability of the molecule to inhibit protein kinases involved in deregulated cell growth in cancer cells. PMID:24114481

  3. Quercetin Reduces Ehrlich Tumor-Induced Cancer Pain in Mice

    PubMed Central

    Calixto-Campos, Cassia; Corrêa, Mab P.; Carvalho, Thacyana T.; Zarpelon, Ana C.; Hohmann, Miriam S. N.; Rossaneis, Ana C.; Coelho-Silva, Leticia; Pavanelli, Wander R.; Pinge-Filho, Phileno; Crespigio, Jefferson; Bernardy, Catia C. F.; Casagrande, Rubia; Verri, Waldiceu A.

    2015-01-01

    Cancer pain directly affects the patient's quality of life. We have previously demonstrated that the subcutaneous administration of the mammary adenocarcinoma known as Ehrlich tumor induces pain in mice. Several studies have shown that the flavonoid quercetin presents important biological effects, including anti-inflammatory, antioxidant, analgesic, and antitumor activity. Therefore, the analgesic effect and mechanisms of quercetin were evaluated in Ehrlich tumor-induced cancer pain in mice. Intraperitoneal (i.p.) treatments with quercetin reduced Ehrlich tumor-induced mechanical and thermal hyperalgesia, but not paw thickness or histological alterations, indicating an analgesic effect without affecting tumor growth. Regarding the analgesic mechanisms of quercetin, it inhibited the production of hyperalgesic cytokines IL-1β and TNFα and decreased neutrophil recruitment (myeloperoxidase activity) and oxidative stress. Naloxone (opioid receptor antagonist) inhibited quercetin analgesia without interfering with neutrophil recruitment, cytokine production, and oxidative stress. Importantly, cotreatment with morphine and quercetin at doses that were ineffective as single treatment reduced the nociceptive responses. Concluding, quercetin reduces the Ehrlich tumor-induced cancer pain by reducing the production of hyperalgesic cytokines, neutrophil recruitment, and oxidative stress as well as by activating an opioid-dependent analgesic pathway and potentiation of morphine analgesia. Thus, quercetin treatment seems a suitable therapeutic approach for cancer pain that merits further investigation. PMID:26351625

  4. Chemotherapeutic potential of quercetin on human bladder cancer cells.

    PubMed

    Oršolić, Nada; Karač, Ivo; Sirovina, Damir; Kukolj, Marina; Kunštić, Martina; Gajski, Goran; Garaj-Vrhovac, Vera; Štajcar, Damir

    2016-07-28

    In an effort to improve local bladder cancer control, we investigated the cytotoxic and genotoxic effects of quercetin on human bladder cancer T24 cells. The cytotoxic effect of quercetin against T24 cells was examined by MTT test, clonogenic assay as well as DNA damaging effect by comet assay. In addition, the cytotoxic effect of quercetin on the primary culture of papillary urothelial carcinoma (PUC), histopathological stage T1 of low- or high-grade tumours, was investigated. Our analysis demonstrated a high correlation between reduced number of colony and cell viability and an increase in DNA damage of T24 cells incubated with quercetin at doses of 1 and 50 µM during short term incubation (2 h). At all exposure times (24, 48 and 72 h), the efficacy of quercetin, administered at a 10× higher dose compared to T24 cells, was statistically significant (P < 0.05) for the primary culture of PUC. In conclusion, our study suggests that quercetin could inhibit cell proliferation and colony formation of human bladder cancer cells by inducing DNA damage and that quercetin may be an effective chemopreventive and chemotherapeutic agent for papillary urothelial bladder cancer after transurethral resection. PMID:27149655

  5. Quercetin Suppresses Twist to Induce Apoptosis in MCF-7 Breast Cancer Cells

    PubMed Central

    Ranganathan, Santhalakshmi; Halagowder, Devaraj; Sivasithambaram, Niranjali Devaraj

    2015-01-01

    Quercetin is a dietary flavonoid which exerts anti-oxidant, anti-inflammatory and anti-cancer properties. In this study, we investigated the anti-proliferative effect of quercetin in two breast cancer cell lines (MCF-7 and MDA-MB-231), which differed in hormone receptor. IC50 value (37μM) of quercetin showed significant cytotoxicity in MCF-7 cells, which was not observed in MDA-MB-231 cells even at 100μM of quercetin treatment. To study the response of cancer cells to quercetin, with respect to different hormone receptors, both the cell lines were treated with a fixed concentration (40μM) of quercetin. MCF-7 cells on quercetin treatment showed more apoptotic cells with G1 phase arrest. In addition, quercetin effectively suppressed the expression of CyclinD1, p21, Twist and phospho p38MAPK, which was not observed in MDA-MB-231 cells. To analyse the molecular mechanism of quercetin in exerting an apoptotic effect in MCF-7 cells, Twist was over-expressed and the molecular changes were observed after quercetin administration. Quercetin effectively regulated the expression of Twist, in turn p16 and p21 which induced apoptosis in MCF-7 cells. In conclusion, quercetin induces apoptosis in breast cancer cells through suppression of Twist via p38MAPK pathway. PMID:26491966

  6. Effects of quercetin on the proliferation of breast cancer cells and expression of survivin in vitro

    PubMed Central

    DENG, XIAO-HUI; SONG, HAI-YAN; ZHOU, YING-FENG; YUAN, GUO-YAN; ZHENG, FENG-JIN

    2013-01-01

    Quercetin is a hydrophobic agent with potential anticancer activity. The aim of the present study was to observe the effects of quercetin on the proliferation of the breast cancer cell line MCF-7 and the gene expression of survivin. The molecular mechanism underlying the antiproliferative effect of quercetin was also investigated. MCF-7 breast cancer cells were treated with various concentrations of quercetin. The inhibitory effect of quercetin on proliferation was detected using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method and the inhibition rate was calculated. Cellular apoptosis was detected by immunocytochemistry and survivin mRNA expression levels were observed using reverse transcription-polymerase chain reaction (RT-PCR). Western blot analysis was used to analyze changes in the expression levels of survivin protein. Quercetin induced the apoptosis of MCF-7 cells and inhibited the proliferation of the MCF-7 breast cancer cells in a time- and concentration-dependent manner. The mRNA and protein expression levels of survivin were reduced as the concentration of quercetin increased. Quercetin inhibited the growth of MCF-7 cells and promoted apoptosis by inducing G0/ G1 phase arrest. It also regulated the expression of survivin mRNA in MCF-7 cells, which may be the mechanism underlying its antitumor effect. PMID:24223637

  7. Quercetin suppresses insulin receptor signaling through inhibition of the insulin ligand–receptor binding and therefore impairs cancer cell proliferation

    SciTech Connect

    Wang, Feng; Yang, Yong

    2014-10-03

    Graphical abstract: - Highlights: • Quercetin inhibits insulin ligand–receptor interactions. • Quercetin reduces downstream insulin receptor signaling. • Quercetin blocks insulin induced glucose uptake. • Quercetin suppresses insulin stimulated cancer cell proliferation and tumor growth. - Abstract: Although the flavonoid quercetin is known to inhibit activation of insulin receptor signaling, the inhibitory mechanism is largely unknown. In this study, we demonstrate that quercetin suppresses insulin induced dimerization of the insulin receptor (IR) through interfering with ligand–receptor interactions, which reduces the phosphorylation of IR and Akt. This inhibitory effect further inhibits insulin stimulated glucose uptake due to decreased cell membrane translocation of glucose transporter 4 (GLUT4), resulting in impaired cancer cell proliferation. The effect of quercetin in inhibiting tumor growth was also evident in an in vivo model, indicating a potential future application for quercetin in the treatment of cancers.

  8. Quercetin 3-O-glucoside suppresses epidermal growth factor-induced migration by inhibiting EGFR signaling in pancreatic cancer cells.

    PubMed

    Lee, Jungwhoi; Han, Song-I; Yun, Jeong-Hun; Kim, Jae Hoon

    2015-12-01

    Pancreatic cancer is one of the most dangerous cancers and is associated with a grave prognosis. Despite increased knowledge of the complex signaling networks responsible for progression of pancreatic cancer, many challenging therapies have fallen short of expectations. In this study, we examined the anti-migratory effect of quercetin 3-O-glucoside in epidermal growth factor-induced cell migration by inhibiting EGF receptor (EGFR) signaling in several human pancreatic cancer cell lines. Treatment with quercetin, quercetin 3-O-glucoside, and quercetin 7-O-glucoside differentially suppressed epidermal growth factor-induced migration activity of human pancreatic cancer cells. In particular, quercetin 3-O-glucoside strongly inhibited the infiltration activity of pancreatic cancer cells in a dose-dependent manner. Furthermore, quercetin 3-O-glucoside exerted the anti-migratory effect even at a relatively low dose compared with other forms of quercetin. The anti-tumor effects of quercetin 3-O-glucoside were mediated by selectively inhibiting the EGFR-mediated FAK, AKT, MEK1/2, and ERK1/2 signaling pathway. Combinatorial treatment with quercetin 3-O-glucoside plus gemcitabine showed the synergistic anti-migratory effect on epidermal growth factor-induced cell migration in human pancreatic cancer cell lines. These results suggest that quercetin 3-O-glucoside has potential for anti-metastatic therapy in human pancreatic cancer. PMID:26109002

  9. Quercetin-Induced Cell Death in Human Papillary Thyroid Cancer (B-CPAP) Cells

    PubMed Central

    Mutlu Altundağ, Ergül; Kasacı, Tolga; Yılmaz, Ayşe Mine; Karademir, Betül; Koçtürk, Semra; Taga, Yavuz; Yalçın, A. Süha

    2016-01-01

    In this study, we have investigated the antiproliferative effect of quercetin on human papillary thyroid cancer cells and determined the apoptotic mechanisms underlying its actions. We have used different concentrations of quercetin to induce apoptosis and measured cell viability. Apoptosis and cell cycle analysis was determined by flow cytometry using Annexin V and propidium iodide. Finally, we have measured changes in caspase-3 and cleaved poly(ADP-ribose) polymerase (PARP) protein expression levels as hallmarks of apoptosis and Hsp90 protein expression level as a marker of proteasome activity in treated and control cells. Quercetin treatment of human papillary thyroid cancer cells resulted in decreased cell proliferation and increased rate of apoptosis by caspase activation. Furthermore, it was demonstrated that quercetin induces cancer cell apoptosis by downregulating the levels of Hsp90. In conclusion, we have shown that quercetin induces downregulation of Hsp90 expression that may be involved in the decrease of chymotrypsin-like proteasome activity which, in order, induces inhibition of growth and causes cell death in thyroid cancer cells. Thus, quercetin appears to be a promising candidate drug for Hsp90 downregulation and apoptosis of thyroid cancer cells. PMID:27057371

  10. Interfering with ROS Metabolism in Cancer Cells: The Potential Role of Quercetin

    PubMed Central

    Gibellini, Lara; Pinti, Marcello; Nasi, Milena; De Biasi, Sara; Roat, Erika; Bertoncelli, Linda; Cossarizza, Andrea

    2010-01-01

    A main feature of cancer cells, when compared to normal ones, is a persistent pro-oxidative state that leads to an intrinsic oxidative stress. Cancer cells have higher levels of reactive oxygen species (ROS) than normal cells, and ROS are, in turn, responsible for the maintenance of the cancer phenotype. Persistent ROS stress may induce adaptive stress responses, enabling cancer cells to survive with high levels of ROS and maintain cellular viability. However, excessive ROS levels render cancer cells highly susceptible to quercetin, one of the main dietary flavonoids. Quercetin depletes intracellular glutathione and increases intracellular ROS to a level that can cause cell death. PMID:24281116

  11. Quercetin induces human colon cancer cells apoptosis by inhibiting the nuclear factor-kappa B Pathway

    PubMed Central

    Zhang, Xiang-An; Zhang, Shuangxi; Yin, Qing; Zhang, Jing

    2015-01-01

    Quercetin can inhibit the growth of cancer cells with the ability to act as chemopreventers. Its cancer-preventive effect has been attributed to various mechanisms, including the induction of cell-cycle arrest and/or apoptosis as well as the antioxidant functions. Nuclear factor kappa-B (NF-κB) is a signaling pathway that controls transcriptional activation of genes important for tight regulation of many cellular processes and is aberrantly expressed in many types of cancer. Inhibitors of NF-κB pathway have shown potential anti-tumor activities. However, it is not fully elucidated in colon cancer. In this study, we demonstrate that quercetin induces apoptosis in human colon cancer CACO-2 and SW-620 cells through inhibiting NF-κB pathway, as well as down-regulation of B-cell lymphoma 2 and up-regulation of Bax, thus providing basis for clinical application of quercetin in colon cancer cases. PMID:25829782

  12. Anticancer effect and mechanism of polymer micelle-encapsulated quercetin on ovarian cancer

    NASA Astrophysics Data System (ADS)

    Gao, Xiang; Wang, Bilan; Wei, Xiawei; Men, Ke; Zheng, Fengjin; Zhou, Yingfeng; Zheng, Yu; Gou, Maling; Huang, Meijuan; Guo, Gang; Huang, Ning; Qian, Zhiyong; Wei, Yuquan

    2012-10-01

    Encapsulation of hydrophobic agents in polymer micelles can improve the water solubility of cargos, contributing to develop novel drugs. Quercetin (QU) is a hydrophobic agent with potential anticancer activity. In this work, we encapsulated QU into biodegradable monomethoxy poly(ethylene glycol)-poly(ε-caprolactone) (MPEG-PCL) micelles and tried to provide proof-of-principle for treating ovarian cancer with this nano-formulation of quercetin. These QU loaded MPEG-PCL (QU/MPEG-PCL) micelles with drug loading of 6.9% had a mean particle size of 36 nm, rendering the complete dispersion of quercetin in water. QU inhibited the growth of A2780S ovarian cancer cells on a dose dependent manner in vitro. Intravenous administration of QU/MPEG-PCL micelles significantly suppressed the growth of established xenograft A2780S ovarian tumors through causing cancer cell apoptosis and inhibiting angiogenesis in vivo. Furthermore, the anticancer activity of quercetin on ovarian cancer cells was studied in vitro. Quercetin treatment induced the apoptosis of A2780S cells associated with activating caspase-3 and caspase-9. MCL-1 downregulation, Bcl-2 downregulation, Bax upregulation and mitochondrial transmembrane potential change were observed, suggesting that quercetin may induce apoptosis of A2780S cells through the mitochondrial apoptotic pathway. Otherwise, quercetin treatment decreased phosphorylated p44/42 mitogen-activated protein kinase and phosphorylated Akt, contributing to inhibition of A2780S cell proliferation. Our data suggested that QU/MPEG-PCL micelles were a novel nano-formulation of quercetin with a potential clinical application in ovarian cancer therapy.

  13. Quercetin induces bladder cancer cells apoptosis by activation of AMPK signaling pathway

    PubMed Central

    Su, Qiongli; Peng, Mei; Zhang, Yuqing; Xu, Wanjun; Darko, Kwame Oteng; Tao, Ting; Huang, Yanjun; Tao, Xiaojun; Yang, Xiaoping

    2016-01-01

    Quercetin, a natural existing polyphenol compound, has shown anticancer capacity for liver, breast, nasopharyngeal and prostate carcinoma but has not been clinically approved yet. This might be due to lack of clear mechanistic picture. Bladder cancer is one of the most common cancers of the urinary tract in the world. In China, bladder cancer has the highest rate of incidence out of all malignancies of the urinary system. The anticancer application of quercetin on bladder cancer has not been investigated either. This study was aimed to examine the mechanisms of quercetin on inhibition of bladder cancer. First, two human and one murine bladder cancer cell lines were tested in vitro for inhibitory sensitivity by MTT and cologenic assays. Second, AMPK pathway including 4E-BP1 and S6K were examined by western blot. Quercetin induces apoptosis and inhibits migration. We are the first to show that quercetin displays potent inhibition on bladder cancer cells via activation of AMPK pathway. PMID:27186419

  14. Characterisation of metabolites of the putative cancer chemopreventive agent quercetin and their effect on cyclo-oxygenase activity

    PubMed Central

    Jones, D J L; Lamb, J H; Verschoyle, R D; Howells, L M; Butterworth, M; Lim, C K; Ferry, D; Farmer, P B; Gescher, A J

    2004-01-01

    Quercetin (3,5,7,3′,4′-pentahydroxyflavone) is a flavone with putative ability to prevent cancer and cardiovascular diseases. Its metabolism was evaluated in rats and human. Rats received quercetin via the intravenous (i.v.) route and metabolites were isolated from the plasma, urine and bile. Analysis was by high-performance liquid chromatography and confirmation of species identity was achieved by mass spectrometry. Quercetin and isorhamnetin, the 3′-O-methyl analogue, were found in both the plasma and urine. In addition, several polar peaks were characterised as sulphated and glucuronidated conjugates of quercetin and isorhamnetin. Extension of the metabolism studies to a cancer patient who had received quercetin as an i.v. bolus showed that (Quercetin removed) isorhamnetin and quercetin 3′-O-sulphate were major plasma metabolites. As a catechol, quercetin can potentially be converted to a quinone and subsequently conjugated with glutathione (GSH). Oxidation of quercetin with mushroom tyrosinase in the presence of GSH furnished GSH conjugates of quercetin, two mono- and one bis-substituted conjugates. However, these species were not found in biomatrices in rats treated with quercetin. As cyclo-oxygenase-2 (COX-2) expression is mechanistically linked to carcinogenesis, we examined whether quercetin and its metabolites can inhibit COX-2 in a human colorectal cancer cell line (HCA-7). Isorhamnetin and its 4′-isomer tamarixetin were potent inhibitors, reflected in a 90% decrease in prostaglandin E-2 (PGE-2) levels, a marker of COX-2 activity. Quercetin was less effective, with a 50% decline. Quercetin 3- and 7-O-sulphate had no effect on PGE-2. The results indicate that quercetin may exert its pharmacological effects, at least in part, via its metabolites. PMID:15292928

  15. Quercetin regulates β-catenin signaling and reduces the migration of triple negative breast cancer.

    PubMed

    Srinivasan, Asha; Thangavel, Chellappagounder; Liu, Yi; Shoyele, Sunday; Den, Robert B; Selvakumar, Ponniah; Lakshmikuttyamma, Ashakumary

    2016-05-01

    Triple negative breast cancer (TNBC) is characterized by a lack in estrogen, progesterone, and epidermal growth factor 2 receptors. TNBC exhibits most of the characteristics of basal-like and claudin-low breast cancer subtypes. The main contributor in the mortality of TNBC is due to the higher invasive and migratory ability of these tumor cells. Some plant flavonoids inhibit the epithelial mesenchymal transition (EMT) of tumor cells and suppress cancer metastasis. In this study, we aimed to determine whether the flavonoid quercetin is effective in modulating the molecular signaling associated with EMT in TNBC. Our data indicated that quercetin can induce the expression of E-cadherin and also downregulate vimentin levels in TNBC. The ability of quercetin to modulate these EMT markers resulted in a mesenchymal-to-epithelial transition (MET). Quercetin-induced MET was linked with the alteration of nuclear localization of β-catenin and modulation of β-catenin target genes such as cyclin D1 and c-Myc. Furthermore, we observed that quercetin induced the anti-tumor activity of doxorubicin by inhibiting the migratory ability of TNBC cells. These results suggested that quercetin may inhibit TNBC metastasis and also improve the therapeutic efficacy of existing chemotherapeutic drugs. © 2015 Wiley Periodicals, Inc. PMID:25968914

  16. Quercetin inhibits human breast cancer cell proliferation and induces apoptosis via Bcl-2 and Bax regulation.

    PubMed

    Duo, Jian; Ying, Guo-Guang; Wang, Guo-Wen; Zhang, Li

    2012-06-01

    Breast cancer is a disease in which cancer cells form in the tissues of the breast. The present study aimed to explore the effect of the flavonoid compound quercetin on the growth and apoptosis of human breast cancer cells. Varying concentrations (12.5, 25, 50, 100, 200 µM) of quercetin were applied to cultured MCF-7 human breast cancer cells for defined lengths of time. At 50 to 200 µM doses, quercetin significantly inhibited the proliferation of MCF-7 cells assessed by MTT colorimetry, in both dose- and time-dependent manners (P<0.05). The compound also increased apoptosis after 48 h of exposure (P<0.05). Furthermore, following quercetin treatment Bcl-2 expression decreased significantly while Bax expression increased significantly (P<0.05). In brief, quercetin inhibits cell growth and induces apoptosis in MCF-7 human breast cancer cells. The mechanisms behind these effects may stem from the downregulation of Bcl-2 protein expression and upregulation of Bax expression. PMID:22447039

  17. Enhancing the anti-colon cancer activity of quercetin by self-assembled micelles.

    PubMed

    Xu, Guangya; Shi, Huashan; Ren, Laibin; Gou, Hongfeng; Gong, Daoyin; Gao, Xiang; Huang, Ning

    2015-01-01

    Colorectal cancer, a type of malignant neoplasm originating from the epithelial cells lining the colon and/or rectum, has been the third most frequent malignancy and one of the leading causes of cancer-related deaths in the US. As a bioflavonoid with high anticancer potential, quercetin (Qu) has been proved to have a prospective applicability in chemotherapy for a series of cancers. However, quercetin is a hydrophobic drug, the poor hydrophilicity of which hinders its clinical usage in cancer therapy. Therefore, a strategy to improve the solubility of quercetin in water and/or enhance the bioavailability is desired. Encapsulating the poorly water-soluble, hydrophobic agents into polymer micelles could facilitate the dissolution of drugs in water. In our study, nanotechnology was employed, and quercetin was encapsulated into the biodegradable nanosized amphiphilic block copolymers of monomethoxy poly(ethylene glycol)-poly(ε-caprolactone) (MPEG-PCL), attempting to present positive evidences that this drug delivery system of polymeric micelles is effective. The quercetin-loaded MPEG-PCL nanomicelles (Qu-M), with a high drug loading of 6.85% and a minor particle size of 34.8 nm, completely dispersed in the water and released quercetin in a prolonged period in vitro and in vivo. At the same time, compared with free quercetin, Qu-M exhibited improved apoptosis induction and cell growth inhibition effects in CT26 cells in vitro. Moreover, the mice subcutaneous CT26 colon cancer model was established to evaluate the therapy efficiency of Qu-M in detail, in which enhanced anti-colon cancer effect was proved in vivo: Qu-M were more efficacious in repressing the growth of colon tumor than free quercetin. In addition, better effects of Qu-M on inducing cell apoptosis, inhibiting tumor angiogenesis, and restraining cell proliferation were observed by immunofluorescence analysis. Our study indicated that Qu-M were a novel nanoagent of quercetin with an enhanced antitumor

  18. Cell-specific biomarkers and targeted biopharmaceuticals for breast cancer treatment.

    PubMed

    Liu, Mei; Li, Zhiyang; Yang, Jingjing; Jiang, Yanyun; Chen, Zhongsi; Ali, Zeeshan; He, Nongyue; Wang, Zhifei

    2016-08-01

    Breast cancer is the second leading cause of cancer death among women, and its related treatment has been attracting significant attention over the past decades. Among the various treatments, targeted therapy has shown great promise as a precision treatment, by binding to cancer cell-specific biomarkers. So far, great achievements have been made in targeted therapy of breast cancer. In this review, we first discuss cell-specific biomarkers, which are not only useful for classification of breast cancer subtyping but also can be utilized as goals for targeted therapy. Then, the innovative and generic-targeted biopharmaceuticals for breast cancer, including monoclonal antibodies, non-antibody proteins and small molecule drugs, are reviewed. Finally, we provide our outlook on future developments of biopharmaceuticals, and provide solutions to problems in this field. PMID:27312135

  19. Quercetin sensitizes pancreatic cancer cells to TRAIL-induced apoptosis through JNK-mediated cFLIP turnover.

    PubMed

    Kim, Ji Hye; Kim, Min Joo; Choi, Kyung-Chul; Son, Jaekyoung

    2016-09-01

    Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising anticancer agent that can selectively kill cancer cells. Nonetheless, many cancers are resistant to TRAIL, and the molecular mechanisms of TRAIL resistance in cancer, particularly pancreatic cancer, are still unclear. In this study, we tested the hypothesis that quercetin, a flavonoid, induces apoptosis in TRAIL-resistant pancreatic cancer cells. Although quercetin alone had no significant cytotoxic effect, when combined with TRAIL, it promoted TRAIL-induced apoptosis that required mitochondrial outer membrane permeabilization. A BH3-only protein BID knockdown dramatically attenuated TRAIL/quercetin-induced apoptosis. The expression levels of cellular FLICE-like inhibitory protein (cFLIP) decreased in a dose-dependent manner in the presence of quercetin, and overexpression of cFLIP was able to robustly rescue pancreatic cancer cells from TRAIL/quercetin-induced apoptosis. Additionally, quercetin activated c-Jun N-terminal kinase (JNK) in a dose-dependent manner, which in turn induced the proteasomal degradation of cFLIP, and JNK activation also sensitized pancreatic cancer cells to TRAIL-induced apoptosis. Thus, our results suggest that quercetin induces TRAIL-induced apoptosis via JNK activation-mediated cFLIP turnover. PMID:27477310

  20. Arctigenin in combination with quercetin synergistically enhances the anti-proliferative effect in prostate cancer cells

    PubMed Central

    Wang, Piwen; Phan, Tien; Gordon, David; Chung, Seyung; Henning, Susanne M.; Vadgama, Jaydutt V.

    2014-01-01

    Scope We investigated whether a combination of two promising chemopreventive agents arctigenin and quercetin increases the anti-carcinogenic potency at lower concentrations than necessary when used individually in prostate cancer. Methods and results Androgen-dependent LAPC-4 and LNCaP prostate cancer cells were treated with low doses of arctigenin and quercetin alone or in combination for 48h. The anti-proliferative activity of arctigenin was 10-20 fold stronger than quercetin in both cell lines. Their combination synergistically enhanced the anti-proliferative effect, with a stronger effect in androgen receptor (AR) wild-type LAPC-4 cells than in AR mutated LNCaP cells. Arctigenin demonstrated a strong ability to inhibit AR protein expression in LAPC-4 cells. The combination treatment significantly inhibited both AR and PI3K/Akt pathways compared to control. A protein array analysis revealed that the mixture targets multiple pathways particularly in LAPC-4 cells including Stat3 pathway. The mixture significantly inhibited the expression of several oncogenic microRNAs including miR-21, miR-19b, and miR-148a compared to control. The mixture also enhanced the inhibition of cell migration in both cell lines compared to individual compounds tested. Conclusion The combination of arctigenin and quercetin, that target similar pathways, at low physiological doses, provides a novel regimen with enhanced chemoprevention in prostate cancer. PMID:25380086

  1. Phenotype-based cell-specific metabolic modeling reveals metabolic liabilities of cancer.

    PubMed

    Yizhak, Keren; Gaude, Edoardo; Le Dévédec, Sylvia; Waldman, Yedael Y; Stein, Gideon Y; van de Water, Bob; Frezza, Christian; Ruppin, Eytan

    2014-01-01

    Utilizing molecular data to derive functional physiological models tailored for specific cancer cells can facilitate the use of individually tailored therapies. To this end we present an approach termed PRIME for generating cell-specific genome-scale metabolic models (GSMMs) based on molecular and phenotypic data. We build >280 models of normal and cancer cell-lines that successfully predict metabolic phenotypes in an individual manner. We utilize this set of cell-specific models to predict drug targets that selectively inhibit cancerous but not normal cell proliferation. The top predicted target, MLYCD, is experimentally validated and the metabolic effects of MLYCD depletion investigated. Furthermore, we tested cell-specific predicted responses to the inhibition of metabolic enzymes, and successfully inferred the prognosis of cancer patients based on their PRIME-derived individual GSMMs. These results lay a computational basis and a counterpart experimental proof of concept for future personalized metabolic modeling applications, enhancing the search for novel selective anticancer therapies. PMID:25415239

  2. Phenotype-based cell-specific metabolic modeling reveals metabolic liabilities of cancer

    PubMed Central

    Le Dévédec, Sylvia; Waldman, Yedael Y; Stein, Gideon Y; van de Water, Bob

    2014-01-01

    Utilizing molecular data to derive functional physiological models tailored for specific cancer cells can facilitate the use of individually tailored therapies. To this end we present an approach termed PRIME for generating cell-specific genome-scale metabolic models (GSMMs) based on molecular and phenotypic data. We build >280 models of normal and cancer cell-lines that successfully predict metabolic phenotypes in an individual manner. We utilize this set of cell-specific models to predict drug targets that selectively inhibit cancerous but not normal cell proliferation. The top predicted target, MLYCD, is experimentally validated and the metabolic effects of MLYCD depletion investigated. Furthermore, we tested cell-specific predicted responses to the inhibition of metabolic enzymes, and successfully inferred the prognosis of cancer patients based on their PRIME-derived individual GSMMs. These results lay a computational basis and a counterpart experimental proof of concept for future personalized metabolic modeling applications, enhancing the search for novel selective anticancer therapies. DOI: http://dx.doi.org/10.7554/eLife.03641.001 PMID:25415239

  3. Quercetin Supplementation Attenuates the Progression of Cancer Cachexia in ApcMin/+ Mice123

    PubMed Central

    Velázquez, Kandy T.; Enos, Reilly T.; Narsale, Aditi A.; Puppa, Melissa J.; Davis, J. Mark; Murphy, E. Angela; Carson, James A.

    2014-01-01

    Although there are currently no approved treatments for cancer cachexia, there is an intensified interest in developing therapies because of the high mortality index associated with muscle wasting diseases. Successful treatment of the cachectic patient focuses on improving or maintaining body weight and musculoskeletal function. Nutraceutical compounds, including the natural phytochemical quercetin, are being examined as potential treatments because of their anti-inflammatory, antioxidant, and anticarcinogenic properties. The purpose of this study was to determine the effect of quercetin supplementation on the progression of cachexia in the adenomatous polyposis coli (Apc)Min/+ mouse model of colorectal cancer. At 15 wk of age, C57BL/6 and male ApcMin/+ mice were supplemented with 25 mg/kg of quercetin or vehicle solution mix of Tang juice and water (V) daily for 3 wk. Body weight, strength, neuromuscular performance, and fatigue were assessed before and after quercetin or V interventions. Indicators of metabolic dysfunction and inflammatory signaling were also assessed. During the treatment period, the relative decrease in body weight in the ApcMin/+ mice gavaged with V (ApcMin/+V; −14% ± 2.3) was higher than in control mice gavaged with V (+0.6% ± 1.0), control mice gavaged with quercetin (−2% ± 1.0), and ApcMin/+ mice gavaged with quercetin (ApcMin/+Q; −9% ± 1.3). At 18 wk of age, the loss of grip strength and muscle mass shown in ApcMin/+V mice was significantly attenuated (P < 0.05) in ApcMin/+Q mice. Furthermore, ApcMin/+V mice had an induction of plasma interleukin-6 and muscle signal transducer and activator of transcription 3 phosphorylation, which were significantly (P < 0.05) mitigated in ApcMin/+Q mice, despite having a similar tumor burden. Quercetin treatment did not improve treadmill run-time-to-fatigue, hyperglycemia, or hyperlipidemia in cachectic ApcMin/+ mice. Overall, quercetin supplementation positively affected several aspects of

  4. Cancer cell specific cytotoxic gene expression mediated by ARF tumor suppressor promoter constructs.

    PubMed

    Kurayoshi, Kenta; Ozono, Eiko; Iwanaga, Ritsuko; Bradford, Andrew P; Komori, Hideyuki; Ohtani, Kiyoshi

    2014-07-18

    In current cancer treatment protocols, such as radiation and chemotherapy, side effects on normal cells are major obstacles to radical therapy. To avoid these side effects, a cancer cell-specific approach is needed. One way to specifically target cancer cells is to utilize a cancer specific promoter to express a cytotoxic gene (suicide gene therapy) or a viral gene required for viral replication (oncolytic virotherapy). For this purpose, the selected promoter should have minimal activity in normal cells to avoid side effects, and high activity in a wide variety of cancers to obtain optimal therapeutic efficacy. In contrast to the AFP, CEA and PSA promoters, which have high activity only in a limited spectrum of tumors, the E2F1 promoter exhibits high activity in wide variety of cancers. This is based on the mechanism of carcinogenesis. Defects in the RB pathway and activation of the transcription factor E2F, the main target of the RB pathway, are observed in almost all cancers. Consequently, the E2F1 promoter, which is mainly regulated by E2F, has high activity in wide variety of cancers. However, E2F is also activated by growth stimulation in normal growing cells, suggesting that the E2F1 promoter may also be highly active in normal growing cells. In contrast, we found that the tumor suppressor ARF promoter is activated by deregulated E2F activity, induced by forced inactivation of pRB, but does not respond to physiological E2F activity induced by growth stimulation. We also found that the deregulated E2F activity, which activates the ARF promoter, is detected only in cancer cell lines. These observations suggest that ARF promoter is activated by E2F only in cancer cells and therefore may be more cancer cell-specific than E2F1 promoter to drive gene expression. We show here that the ARF promoter has lower activity in normal growing fibroblasts and shows higher cancer cell-specificity compared to the E2F1 promoter. We also demonstrate that adenovirus expressing HSV

  5. Quercetin inhibits a large panel of kinases implicated in cancer cell biology.

    PubMed

    Boly, Rainatou; Gras, Thierry; Lamkami, Touria; Guissou, Pierre; Serteyn, Didier; Kiss, Robert; Dubois, Jacques

    2011-03-01

    Flavonoids are polyphenolic secondary metabolites from plants that possess a common phenylbenzopyrone structure (C6-C3-C6). Depending upon variations in their heterocyclic C-ring, flavonoids are categorised into one of the following groups: flavones, flavonols, flavanones, flavanols, anthocyanidins, isoflavones or chalcones. Flavonols include, among others, the molecules quercetin, myricetin and kaempferol. The anticancer activity of flavonols was first attributed to their electron-donating ability, which comes from the presence of phenolic hydroxyl groups. However, an emerging view is that flavonoids, including quercetin, may also exert modulatory actions in cells by acting through the protein kinase and lipid kinase signalling pathways. Data from the current study showed that 2 μM quercetin, a low concentration that represents less than 10% of its IC50 growth-inhibitory concentration as calculated from the average of eight distinct cancer cell lines, decreased the activity of 16 kinases by more than 80%, including ABL1, Aurora-A, -B, -C, CLK1, FLT3, JAK3, MET, NEK4, NEK9, PAK3, PIM1, RET, FGF-R2, PDGF-Rα and -Rß. Many of these kinases are involved in the control of mitotic processes. Quantitative video microscopy analyses revealed that quercetin displayed strong anti-mitotic activity, leading to cell death. In conclusion, quercetin partly exerts its anticancer activity through the inhibition of the activity of a large set of kinases. Quercetin could be an interesting chemical scaffold from which to generate novel derivatives possessing various types of anti-kinase activities. PMID:21206969

  6. Cancer cell specific cytotoxic gene expression mediated by ARF tumor suppressor promoter constructs

    SciTech Connect

    Kurayoshi, Kenta; Ozono, Eiko; Iwanaga, Ritsuko; Bradford, Andrew P.; Komori, Hideyuki; Ohtani, Kiyoshi

    2014-07-18

    Highlights: • ARF promoter showed higher responsiveness to deregulated E2F activity than the E2F1 promoter. • ARF promoter showed higher cancer cell-specificity than E2F1 promoter to drive gene expression. • HSV-TK driven by ARF promoter showed higher cancer cell-specific cytotoxicity than that driven by E2F1 promoter. - Abstract: In current cancer treatment protocols, such as radiation and chemotherapy, side effects on normal cells are major obstacles to radical therapy. To avoid these side effects, a cancer cell-specific approach is needed. One way to specifically target cancer cells is to utilize a cancer specific promoter to express a cytotoxic gene (suicide gene therapy) or a viral gene required for viral replication (oncolytic virotherapy). For this purpose, the selected promoter should have minimal activity in normal cells to avoid side effects, and high activity in a wide variety of cancers to obtain optimal therapeutic efficacy. In contrast to the AFP, CEA and PSA promoters, which have high activity only in a limited spectrum of tumors, the E2F1 promoter exhibits high activity in wide variety of cancers. This is based on the mechanism of carcinogenesis. Defects in the RB pathway and activation of the transcription factor E2F, the main target of the RB pathway, are observed in almost all cancers. Consequently, the E2F1 promoter, which is mainly regulated by E2F, has high activity in wide variety of cancers. However, E2F is also activated by growth stimulation in normal growing cells, suggesting that the E2F1 promoter may also be highly active in normal growing cells. In contrast, we found that the tumor suppressor ARF promoter is activated by deregulated E2F activity, induced by forced inactivation of pRB, but does not respond to physiological E2F activity induced by growth stimulation. We also found that the deregulated E2F activity, which activates the ARF promoter, is detected only in cancer cell lines. These observations suggest that ARF promoter

  7. A dietary pattern rich in lignans, quercetin and resveratrol decreases the risk of oesophageal cancer.

    PubMed

    Lin, Yulan; Yngve, Agneta; Lagergren, Jesper; Lu, Yunxia

    2014-12-28

    Dietary lignans, quercetin and resveratrol have oestrogenic properties, and animal studies suggest that they synergistically decrease cancer risk. A protective effect of lignans on the development of oesophageal cancer in humans has recently been demonstrated, and the present study aimed to test whether these three phytochemicals synergistically decrease the risk of oesophageal cancer. Data from a Swedish nationwide population-based case-control study that recruited 181 cases of oesophageal adenocarcinoma (OAC), 158 cases of oesophageal squamous-cell carcinoma (OSCC), 255 cases of gastro-oesophageal junctional adenocarcinoma (JAC) and 806 controls were analysed. Exposure data were collected through face-to-face interviews and questionnaires. The intake of lignans, quercetin and resveratrol was assessed using a sixty-three-item FFQ. Reduced-rank regression was used to assess a dietary pattern, and a simplified dietary pattern score was categorised into quintiles on the basis of the distribution among the control subjects. Unconditional multivariable logistic regression provided OR with 95% CI, adjusted for all the potential risk factors. A dietary pattern rich in lignans, quercetin and resveratrol was mainly characterised by a high intake of tea, wine, lettuce, mixed vegetables, tomatoes, and whole-grain bread and a low intake of milk. There were dose-dependent associations between simplified dietary pattern scores and all types of oesophageal cancer (all P for trend < 0.05). On comparing the highest quintiles with the lowest, the adjusted OR were found to be 0.24 (95% CI 0.12, 0.49) for OAC, 0.31 (95% CI 0.15, 0.65) for OSCC, and 0.49 (95% CI 0.28, 0.84) for JAC. The results of the present study indicate that a dietary pattern characterised by the intake of lignans, quercetin and resveratrol may play a protective role in the development of oesophageal cancer in the Swedish population. PMID:25345471

  8. Combinatorial synthesis and screening of cancer cell-specific nanomedicines targeted via phage fusion proteins

    PubMed Central

    Gillespie, James W.; Gross, Amanda L.; Puzyrev, Anatoliy T.; Bedi, Deepa; Petrenko, Valery A.

    2015-01-01

    Active tumor targeting of nanomedicines has recently shown significant improvements in the therapeutic activity of currently existing drug delivery systems, such as liposomal doxorubicin (Doxil/Caelyx/Lipodox). Previously, we have shown that isolated pVIII major coat proteins of the fd-tet filamentous phage vector, containing cancer cell-specific peptide fusions at their N-terminus, can be used as active targeting ligands in a liposomal doxorubicin delivery system in vitro and in vivo. Here, we show a novel major coat protein isolation procedure in 2-propanol that allows spontaneous incorporation of the hydrophobic protein core into preformed liposomal doxorubicin with minimal damage or drug loss while still retaining the targeting ligand exposed for cell-specific targeting. Using a panel of 12 structurally unique ligands with specificity toward breast, lung, and/or pancreatic cancer, we showed the feasibility of pVIII major coat proteins to significantly increase the throughput of targeting ligand screening in a common nanomedicine core. Phage protein-modified Lipodox samples showed an average doxorubicin recovery of 82.8% across all samples with 100% of protein incorporation in the correct orientation (N-terminus exposed). Following cytotoxicity screening in a doxorubicin-sensitive breast cancer line (MCF-7), three major groups of ligands were identified. Ligands showing the most improved cytotoxicity included: DMPGTVLP, ANGRPSMT, VNGRAEAP, and ANDVYLD showing a 25-fold improvement (p < 0.05) in toxicity. Similarly DGQYLGSQ, ETYNQPYL, and GSSEQLYL ligands with specificity toward a doxorubicin-insensitive pancreatic cancer line (PANC-1) showed significant increases in toxicity (2-fold; p < 0.05). Thus, we demonstrated proof-of-concept that pVIII major coat proteins can be screened in significantly higher throughput to identify novel ligands displaying improved therapeutic activity in a desired cancer phenotype. PMID:26157433

  9. Quercetin induces cell cycle arrest and apoptosis in CD133+ cancer stem cells of human colorectal HT29 cancer cell line and enhances anticancer effects of doxorubicin

    PubMed Central

    Atashpour, Shekoufeh; Fouladdel, Shamileh; Movahhed, Tahereh Komeili; Barzegar, Elmira; Ghahremani, Mohammad Hossein; Ostad, Seyed Nasser; Azizi, Ebrahim

    2015-01-01

    Objective(s): The colorectal cancer stem cells (CSCs) with the CD133+ phenotype are a rare fraction of cancer cells with the ability of self-renewal, unlimited proliferation and resistance to treatment. Quercetin has anticancer effects with the advantage of exhibiting low side effects. Therefore, we evaluated the anticancer effects of quercetin and doxorubicin (Dox) in HT29 cancer cells and its isolated CD133+ CSCs. Materials and Methods: The CSCs from HT29 cells were isolated using CD133 antibody conjugated to magnetic beads by MACS. Anticancer effects of quercetin and Dox alone and in combination on HT29 cells and CSCs were evaluated using MTT cytotoxicity assay and flow cytometry analysis of cell cycle distribution and apoptosis induction. Results: The CD133+ CSCs comprised about 10% of HT29 cells. Quercetin and Dox alone and in combination inhibited cell proliferation and induced apoptosis in HT29 cells and to a lesser extent in CSCs. Quercetin enhanced cytotoxicity and apoptosis induction of Dox at low concentration in both cell populations. Quercetin and Dox and their combination induced G2/M arrest in the HT29 cells and to a lesser extent in CSCs. Conclusion: The CSCs were a minor population with a significantly high level of drug resistance within the HT29 cancer cells. Quercetin alone exhibited significant cytotoxic effects on HT29 cells and also increased cytoxicity of Dox in combination therapy. Altogether, our data showed that adding quercetin to Dox chemotherapy is an effective strategy for treatment of both CSCs and bulk tumor cells. PMID:26351552

  10. The Dietary Bioflavonoid, Quercetin, Selectively Induces Apoptosis of Prostate Cancer Cells by Down-Regulating the Expression of Heat Shock Protein 90

    PubMed Central

    Aalinkeel, Ravikumar; Bindukumar, B.; Reynolds, Jessica L.; Sykes, Donald E.; Mahajan, Supriya D.; Chadha, Kailash C.; Schwartz, Stanley A.

    2010-01-01

    BACKGROUND Human and animal studies have suggested that diet-derived flavonoids, in particular quercetin may play a beneficial role by preventing or inhibiting oncogenesis, but the underlying mechanism remains unclear. The aim of this study is to evaluate the effect(s) of quercetin on normal and malignant prostate cells and to identify the target(s) of quercetin’s action. METHODOLOGY We addressed this question using cells in culture and investigated whether quercetin affects key biological processes responsible for tumor cell properties such as cell proliferation and apoptosis and also studied the effect of quercetin on the proteome of prostate cancer cells using difference gel electrophoresis (DIGE) to assess changes in the expression of relevant proteins. RESULTS Our findings demonstrate that quercetin treatment of prostate cancer cells results in decreased cell proliferation and viability. Furthermore, we demonstrate that quercetin promotes cancer cell apoptosis by down-regulating the levels of heat shock protein (Hsp) 90. Depletion of Hsp90 by quercetin results in decreased cell viability, levels of surrogate markers of Hsp90 inhibition (intracellular and secreted), induced apoptosis and activation of caspases in cancer cells but not in normal prostate epithelial cells. Knockdown of Hsp90 by short interfering RNA also resulted in induction apoptosis similar to quercetin in cancer cells as indicated by annexin V staining. CONCLUSION Our results demonstrate that quercetin down-regulates the expression of Hsp90 which, in turn, induces inhibition of growth and cell death in prostate cancer cells while exerting no quantifiable effect on normal prostate epithelial cells. PMID:18726985

  11. Quercetin induces caspase-dependent extrinsic apoptosis through inhibition of signal transducer and activator of transcription 3 signaling in HER2-overexpressing BT-474 breast cancer cells

    PubMed Central

    SEO, HYE-SOOK; KU, JIN MO; CHOI, HAN-SEOK; CHOI, YOUN KYUNG; WOO, JONG-KYU; KIM, MINSOO; KIM, ILHWAN; NA, CHANG HYEOK; HUR, HANSOL; JANG, BO-HYOUNG; SHIN, YONG CHEOL; KO, SEONG-GYU

    2016-01-01

    Flavonoids are assumed to exert beneficial effects in different types of cancers at high concentrations. Yet, their molecular mechanisms of action remain unknown. The present study aimed to examine the effect of quercetin on proliferation and apoptosis in HER2-expressing breast cancer cells. The anti-proliferative effects of quercetin were examined by proliferation, MTT and clonogenic survival assays. The effect of quercetin on expression of apoptotic molecules was determined by western blotting. Luciferase reporter assay was performed to measure signal transducer and activator of transcription 3 (STAT3) transcriptional activity. ELISA assay was performed to measure intracellular MMP-9 levels. Immunocytochemistry was performed to evaluate the nuclear STAT3 level. The results revealed that quercetin inhibited the proliferation of BT-474 cells in a dose- and time-dependent manner. Quercetin also inhibited clonogenic survival (anchorage-dependent and -independent) of BT-474 cells in a dose-dependent manner. These growth inhibitions were accompanied with an increase in sub-G0/G1 apoptotic populations. Quercetin induced caspase-dependent extrinsic apoptosis upregulating the levels of cleaved caspase-8 and cleaved caspase-3, and inducing the cleavage of poly(ADP-ribose) polymerase (PARP). In contrast, quercetin did not induce apoptosis via intrinsic mitochondrial apoptosis pathway since this compound did not decrease the mitochondrial membrane potential and did not affect the levels of B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X protein (BAX). Quercetin reduced the expression of phospho-JAK1 and phospho-STAT3 and decreased STAT3-dependent luciferase reporter gene activity in the BT-474 cells. Quercetin inhibited MMP-9 secretion and decreased the nuclear translocation of STAT3. Our study indicates that quercetin induces apoptosis at concentrations >20 µM through inhibition of STAT3 signaling and could serve as a useful compound to prevent or treat HER2

  12. Quercetin induces caspase-dependent extrinsic apoptosis through inhibition of signal transducer and activator of transcription 3 signaling in HER2-overexpressing BT-474 breast cancer cells.

    PubMed

    Seo, Hye-Sook; Ku, Jin Mo; Choi, Han-Seok; Choi, Youn Kyung; Woo, Jong-Kyu; Kim, Minsoo; Kim, Ilhwan; Na, Chang Hyeok; Hur, Hansol; Jang, Bo-Hyoung; Shin, Yong Cheol; Ko, Seong-Gyu

    2016-07-01

    Flavonoids are assumed to exert beneficial effects in different types of cancers at high concentrations. Yet, their molecular mechanisms of action remain unknown. The present study aimed to examine the effect of quercetin on proliferation and apoptosis in HER2-expressing breast cancer cells. The anti-proliferative effects of quercetin were examined by proliferation, MTT and clonogenic survival assays. The effect of quercetin on expression of apoptotic molecules was determined by western blotting. Luciferase reporter assay was performed to measure signal transducer and activator of transcription 3 (STAT3) transcriptional activity. ELISA assay was performed to measure intracellular MMP-9 levels. Immunocytochemistry was performed to evaluate the nuclear STAT3 level. The results revealed that quercetin inhibited the proliferation of BT-474 cells in a dose- and time-dependent manner. Quercetin also inhibited clonogenic survival (anchorage-dependent and -independent) of BT-474 cells in a dose-dependent manner. These growth inhibitions were accompanied with an increase in sub-G0/G1 apoptotic populations. Quercetin induced caspase-dependent extrinsic apoptosis upregulating the levels of cleaved caspase-8 and cleaved caspase-3, and inducing the cleavage of poly(ADP‑ribose) polymerase (PARP). In contrast, quercetin did not induce apoptosis via intrinsic mitochondrial apoptosis pathway since this compound did not decrease the mitochondrial membrane potential and did not affect the levels of B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X protein (BAX). Quercetin reduced the expression of phospho-JAK1 and phospho-STAT3 and decreased STAT3-dependent luciferase reporter gene activity in the BT-474 cells. Quercetin inhibited MMP-9 secretion and decreased the nuclear translocation of STAT3. Our study indicates that quercetin induces apoptosis at concentrations >20 µM through inhibition of STAT3 signaling and could serve as a useful compound to prevent or treat HER2

  13. Chemical proteomics identifies heterogeneous nuclear ribonucleoprotein (hnRNP) A1 as the molecular target of quercetin in its anti-cancer effects in PC-3 cells.

    PubMed

    Ko, Chia-Chen; Chen, Yun-Ju; Chen, Chih-Ta; Liu, Yu-Chih; Cheng, Fong-Chi; Hsu, Kai-Chao; Chow, Lu-Ping

    2014-08-01

    Quercetin, a flavonoid abundantly present in plants, is widely used as a phytotherapy in prostatitis and prostate cancer. Although quercetin has been reported to have a number of therapeutic effects, the cellular target(s) responsible for its anti-cancer action has not yet been clearly elucidated. Here, employing affinity chromatography and mass spectrometry, we identified heterogeneous nuclear ribonucleoprotein A1 (hnRNPA1) as a direct target of quercetin. A specific interaction between quercetin and hnRNPA1 was validated by immunoblotting and in vitro binding experiments. We found that quercetin bound the C-terminal region of hnRNPA1, impairing the ability of hnRNPA1 to shuttle between the nucleus and cytoplasm and ultimately resulting in its cytoplasmic retention. In addition, hnRNPA1 was recruited to stress granules after treatment of cells with quercetin for up to 48 h, and the levels of cIAP1 (cellular inhibitor of apoptosis), an internal ribosome entry site translation-dependent protein, were reduced by hnRNPA1 regulation. This is the first report that anti-cancer effects of quercetin are mediated, in part, by impairing functions of hnRNPA1, insights that were obtained using a chemical proteomics strategy. PMID:24962584

  14. Quercetin inhibits the growth of human gastric cancer stem cells by inducing mitochondrial-dependent apoptosis through the inhibition of PI3K/Akt signaling.

    PubMed

    Shen, Xinsheng; Si, Yaqing; Wang, Zhao; Wang, Jiachen; Guo, Yongqiang; Zhang, Xiefu

    2016-08-01

    Cancer stem cells (CSCs) have recently been linked to new treatment strategies for gastric cancer due to the critical role which they play as the 'heartbeat' of cancer. In the present study, we explored the effects of quercetin, an anti-inflammatory and antiviral compound, on gastric CSCs (GCSCs). We noted that quercetin exerted pronounced inhibitory effects on GCSC survival. Moreover, quercetin induced cell apoptosis in a mitochondrial-dependent manner, as shown by the reduction in mitochondrial membrane potential, the activation of caspase-3 and -9, and the downregulation of Bcl-2, as well as the upregulation of Bax and cytochrome c (Cyt-c). Additionally, a marked decrease in Akt phosphorylation levels was observed following treatment with quercetin, whereas pre-treatment with fumonisin B1 (FB1, Akt activator) significantly attenuated the inhibitory effects of quercetin on cell growth and its promoting effects on mitochondrial-dependent apoptosis. Notably, FB1 enhanced the expression of Bcl-2, which was inhibited by quercetin, and prevented the decrease in mitochondrial membrane potential induced by quercetin. However, the increase in the levels of caspases, Bax and Cyt-c induced by quercetin was also attenuated by the addition of FB1 to the GCSCs. Therefore, our results demonstrate that quercetin triggers mitochondrial apoptotic-dependent growth inhibition via the blockade of phosphoinositide 3-kinase (PI3K)-Akt signaling in GCSCs, indicating a potential target for the treatment of gastric cancer. PMID:27278820

  15. Inhibition of mitochondrial 2-oxoglutarate dehydrogenase impairs viability of cancer cells in a cell-specific metabolism-dependent manner.

    PubMed

    Bunik, Victoria I; Mkrtchyan, Garik; Grabarska, Aneta; Oppermann, Henry; Daloso, Danilo; Araujo, Wagner L; Juszczak, Malgorzata; Rzeski, Wojciech; Bettendorff, Lucien; Fernie, Alisdair R; Meixensberger, Jürgen; Stepulak, Andrzej; Gaunitz, Frank

    2016-05-01

    2-Oxoglutarate dehydrogenase (OGDH) of the tricarboxylic acid (TCA) cycle is often implied to be inactive in cancer, but this was not experimentally tested. We addressed the question through specific inhibition of OGDH by succinyl phosphonate (SP). SP action on different cancer cells was investigated using indicators of cellular viability and reactive oxygen species (ROS), metabolic profiling and transcriptomics. Relative sensitivity of various cancer cells to SP changed with increasing SP exposure and could differ in the ATP- and NAD(P)H-based assays. Glioblastoma responses to SP revealed metabolic sub-types increasing or decreasing cellular ATP/NAD(P)H ratio under OGDH inhibition. Cancer cell homeostasis was perturbed also when viability indicators were SP-resistant, e.g. in U87 and N2A cells. The transcriptomics database analysis showed that the SP-sensitive cells, such as A549 and T98G, exhibit the lowest expression of OGDH compared to other TCA cycle enzymes, associated with higher expression of affiliated pathways utilizing 2-oxoglutarate. Metabolic profiling confirmed the dependence of cellular SP reactivity on cell-specific expression of the pathways. Thus, oxidative decarboxylation of 2-oxoglutarate is significant for the interdependent homeostasis of NAD(P)H, ATP, ROS and key metabolites in various cancer cells. Assessment of cell-specific responses to OGDH inhibition is of diagnostic value for anticancer strategies. PMID:27027236

  16. Quercetin attenuates the development of 7, 12-dimethyl benz (a) anthracene (DMBA) and croton oil-induced skin cancer in mice

    PubMed Central

    Ali, Huma; Dixit, Savita

    2015-01-01

    Abstract To evaluate the chemopreventive potential of quercetin in an experimental skin carcinogenesis mouse model. Skin tumor was induced by topical application of 7, 12-dimethyl Benz (a) anthracene (DMBA) and Croton oil in Swiss albino mouse. Quercetin was orally administered at a concentration of 200 mg/kg and 400 mg/kg body weight daily for 16 weeks in mouse to evaluate chemopreventive potential. Skin cancer was assessed by histopathological analysis. We found that quercetin reduced the tumor size and the cumulative number of papillomas. The mean latent period was significantly increased as compared to carcinogen treated controls. Quercetin significantly decreased the serum levels of glutamate oxalate transaminase, glutamate pyruvate transaminase, alkaline phosphatase and bilirubin. It significantly increased the levels of glutathione, superoxide dismutase and catalase. The elevated level of lipid peroxides in the control group was significantly inhibited by quercetin. Futhermore, DNA damage was significantly decreased in quercetin treated mice as compared to DMBA and croton oil treated mice. The results suggest that quercetin exerts chemopreventive effect on DMBA and croton oil induced skin cancer in mice by increasing antioxidant activities. PMID:25859269

  17. Quercetin inhibits angiogenesis by targeting calcineurin in the xenograft model of human breast cancer.

    PubMed

    Zhao, Xin; Wang, Qiuting; Yang, Shijun; Chen, Chen; Li, Xiaoya; Liu, Jinyu; Zou, Zhongmei; Cai, Dayong

    2016-06-15

    Vascular endothelial growth factor receptor 2 (VEGFR2) mediated calcineurin/nuclear factor of activated T-cells (NFAT) pathway is crucial in the angiogenesis of human breast cancer. Quercetin (Qu), a flavonoid known to possess anti-angiogenesis and antitumor properties, inhibited calcineurin activity in vitro. Herein, we performed a study in vivo to evaluate the effects of Qu on the angiogenesis in breast cancer. Female BALB/c nude mice were injected with MCF-7 cells into the mammary fat and were randomly divided into four groups. The animals were treated with vehicle solution, tamoxifen (TAM, 5.6mg/kg), tacrolimus (FK506, 3mg/kg), or Qu (34mg/kg) for 21 days, respectively. The results showed that, similar to TAM and FK506, Qu decreased tumor growth, limited oncocyte proliferation and promoted tumor necrosis. Anti-angiogenic actions of Qu were demonstrated as decreased serum VEGF (P<0.01), and sparse microvessel density (P<0.05). Qu significantly inhibited tumor calcineurin activities, and the inhibitory rate was 62.73% in Qu treated animals, compared to that was 72.90% in FK506 group (P>0.05). Effects of Qu on calcineurin/NFAT pathway were confirmed as decreased subcellular located levels of VEGF (P<0.05), VEGFR2 (P<0.05) and NFATc3 (P<0.01), downregulated gene expression of VEGF (P<0.05), VEGFR2 (P<0.05) and NFATc3 (P<0.01), reduced protein levels of VEGF (P<0.05), VEGFR2 (P<0.05), and NFATc3 (P<0.01) in tumor tissues. These findings indicate that Qu inhibit angiogenesis of human breast cancer xenograft in nude mice, which was associated with suppressing calcineurin activity and its regulated pathway activation. PMID:27041643

  18. Quercetin inhibits angiogenesis through thrombospondin-1 upregulation to antagonize human prostate cancer PC-3 cell growth in vitro and in vivo.

    PubMed

    Yang, Feiya; Jiang, Xian; Song, Liming; Wang, Huiping; Mei, Zhu; Xu, Zhiqing; Xing, Nianzeng

    2016-03-01

    The rapid growth, morbidity and mortality of prostate cancer, and the lack of effective treatment have attracted great interests of researchers to find novel cancer therapies aiming to inhibit angiogenesis and tumor growth. Quercetin is a flavonoid compound that widely exists in the nature. Our previous study preliminarily demonstrated that quercetin effectively inhibited human prostate cancer cell xenograft tumor growth by inhibiting angiogenesis. Thrombospondin-1 (TSP-1) is the first reported endogenous anti-angiogenic factor that can inhibit angiogenesis and tumorigenesis. However, the relationship between quercetin inhibiting angiogenesis and TSP-1 upregulation in prostate cancer has not been determined. Thus, we explored the important role of TSP-1 upregulation in reducing angiogenesis and anti-prostate cancer effect of quercetin both in vitro and in vivo for the first time. After the selected doses were used for a certain time, quercetin i) significantly inhibited PC-3 and human umbilical vein endothelial cells (HUVECs) proliferation, migration and invasion in a dose-dependent manner; ⅱ) effectively inhibited prostate cancer PC-3 cell xenograft tumor growth by 37.5% with 75 mg/kg as compared to vehicle control group, more effective than 25 (22.85%) and 50 mg/kg (29.6%); ⅲ) was well tolerated by BALB/c mice and no obvious toxic reactions were observed; ⅳ) greatly reduced angiogenesis and led to higher TSP-1 protein and mRNA expression both in vitro and in vivo in a dose-dependent manner. Therefore, quercetin could increase TSP-1 expression to inhibit angiogenesis resulting in antagonizing prostate cancer PC-3 cell and xenograft tumor growth. The present study can lay a good basis for the subsequent concrete mechanism study and raise the possibility of applying quercetin to clinical for human prostate cancer in the near future. PMID:26676551

  19. New Treatment of Medullary and Papillary Human Thyroid Cancer: Biological Effects of Hyaluronic Acid Hydrogel Loaded With Quercetin Alone or in Combination to an Inhibitor of Aurora Kinase.

    PubMed

    Quagliariello, Vincenzo; Armenia, Emilia; Aurilio, Caterina; Rosso, Francesco; Clemente, Ottavia; de Sena, Gabriele; Barbarisi, Manlio; Barbarisi, Alfonso

    2016-08-01

    The aim of this paper is based on the use of a hyaluronic acid hydrogel of Quercetin tested alone and in combination to an inhibitor of Aurora Kinase type A and B (SNS-314) on human medullary and papillary thyroid cancer cells. Biological investigations were focused on the cellular uptake of the hydrogel, cell viability, antioxidant, and cytokines secretion studies. Quercetin delivered from hydrogel show a time and CD44 dependent interaction with both cell lines with significant anti-inflammatory effects. Combination of Quercetin and SNS-314 leads to a synergistic cytotoxic effect on medullary TT and papillary BCPAP cell lines with a significant reduction of the IC50 value. These results, highlights the importance of synergistic effect of the hyaluronic acid hydrogel of Quercetin with SNS-314 in the regulation of human thyroid cancer cell proliferation and emphasize the anti-tumor activity of these molecules. J. Cell. Physiol. 231: 1784-1795, 2016. © 2015 Wiley Periodicals, Inc. PMID:26660542

  20. Complete Response and Fatigue Improvement With the Combined Use of Cyclophosphamide and Quercetin in a Patient With Metastatic Bladder Cancer

    PubMed Central

    Di Lorenzo, Giuseppe; Pagliuca, Martina; Perillo, Teresa; Zarrella, Aquilino; Verde, Antonio; De Placido, Sabino; Buonerba, Carlo

    2016-01-01

    Abstract Bladder cancer is a major cause of cancer-related mortality, with an estimated 74,000 new cases and 16,000 deaths in the United States in 2015. In patients with metastatic disease, vinflunine and taxanes are the most widely used chemotherapy agents in the second-line setting after failure of platinum-based treatment. Cyclophosphamide has been used in combination with paclitaxel in urothelial carcinoma of the bladder, but there are no data about the effectiveness of cyclophosphamide administered as a single agent. We here describe the first case of an advanced bladder cancer patient suffering from grade 2 fatigue. He benefited from administration of third-line single-agent metronomic oral cyclophosphamide plus oral doses of quercetin. A complete, prolonged radiologic response according to the RECIST criteria 1.1 was achieved with minimal toxicity and an improvement in fatigue. Further studies are required to assess the potential benefits associated with the combined use of cyclophosphamide plus quercetin in advanced bladder cancer patients. PMID:26844468

  1. Preventive effect of the flavonoid, quercetin, on hepatic cancer in rats via oxidant/antioxidant activity: molecular and histological evidences

    PubMed Central

    Seufi, AlaaEddeen M; Ibrahim, Safinz S; Elmaghraby, Tarek K; Hafez, Elsayed E

    2009-01-01

    Background The incidence of hepatocellular carcinoma is increasing in many countries. The estimated number of new cases annually is over 500,000, and the yearly incidence comprises between 2.5 and 7% of patients with liver cirrhosis. The incidence varies between different geographic areas, being higher in developing areas; males are predominantly affected, with a 2:3 male/female ratio Methods Experiments were designed to examine the effect of N-Nitrosodiethylamine (NDEA) as cancer-inducer compound and to confirm the preventive effect of the flavonoid quercetin on hepatocellular carcinoma in rats. Briefly, thirty six male albino rats of Wistar strain were divided into 3 groups: the 1st group was administered NDEA alone (NDEA-treated), the 2nd group was treated simultaneously with NDEA and quercetin (NDEA+Q) and the 3rd group was used as control (CON). Randomly amplified polymorphic DNA polymerase chain reaction (RAPD-PCR) as well as p53-specifi PCR assays were employed to determine genomic difference between treated, and control animals. Histological confirmation as well as oxidant/antioxidant status of the liver tissue was done. Results RAPD analysis of liver samples generated 8 monomorphic bands and 22 polymorphic bands in a total of 30-banded RAPD patterns. Cluster analysis and statistical analyses of RAPD data resulted in grouping control and NDEA+Q samples in the same group with 80% similarity cut-off value. NDEA-treated samples were clustered in a separate group. Specific PCR assay for polymorphism of P53 gene revealed a uniform pattern of allele separation in both control and NDEA+Q samples. Quercetin anticancer effect was exhibited in significant decrease of oxidative stress and significant decrease of antioxidant activity. Histopathological studies showed normal liver histology of the NDEA+Q samples. Meanwhile, several cancer-induced features were clearly observable in NDEA-treated samples. Conclusion This paper demonstrated that preventive effect of

  2. Gd-metallofullerenol nanomaterial as non-toxic breast cancer stem cell-specific inhibitor

    PubMed Central

    Liu, Ying; Chen, Chunying; Qian, Pengxu; Lu, Xuefei; Sun, Baoyun; Zhang, Xiao; Wang, Liming; Gao, Xingfa; Li, Han; Chen, Zhiyun; Tang, Jinglong; Zhang, Weijie; Dong, Jinquan; Bai, Ru; Lobie, Peter E.; Wu, Qingfa; Liu, Suling; Zhang, Huafeng; Zhao, Feng; Wicha, Max S.; Zhu, Tao; Zhao, Yuliang

    2015-01-01

    The contemporary use of nanomedicines for cancer treatment has been largely limited to serving as carriers for existing therapeutic agents. Here, we provide definitive evidence that, the metallofullerenol nanomaterial Gd@C82(OH)22, while essentially not toxic to normal mammary epithelial cells, possesses intrinsic inhibitory activity against triple-negative breast cancer cells. Gd@C82(OH)22 blocks epithelial-to-mesenchymal transition with resultant efficient elimination of breast cancer stem cells (CSCs) resulting in abrogation of tumour initiation and metastasis. In normoxic conditions, Gd@C82(OH)22 mediates these effects by blocking TGF-β signalling. Moreover, under hypoxic conditions found in the tumour microenvironment, cellular uptake of Gd@C82(OH)22 is facilitated where it functions as a bi-potent inhibitor of HIF-1α and TGF-β activities, enhancing CSC elimination. These studies indicate that nanomaterials can be engineered to directly target CSCs. Thus, Gd-metallofullerenol is identified as a kind of non-toxic CSC specific inhibitors with significant therapeutic potential. PMID:25612916

  3. Towards cancer cell-specific phototoxic organometallic rhenium(I) complexes.

    PubMed

    Leonidova, Anna; Pierroz, Vanessa; Rubbiani, Riccardo; Heier, Jakob; Ferrari, Stefano; Gasser, Gilles

    2014-03-21

    Over the recent years, several Re(I) organometallic compounds have been shown to be toxic to various cancer cell lines. However, these compounds lacked sufficient selectivity towards cancer tissues to be used as novel chemotherapeutic agents. In this study, we probe the potential of two known N,N-bis(quinolinoyl) Re(I) tricarbonyl complex derivatives, namely Re(I) tricarbonyl [N,N-bis(quinolin-2-ylmethyl)amino]-4-butane-1-amine (Re-NH₂) and Re(I) tricarbonyl [N,N-bis(quinolin-2-ylmethyl)amino]-5-valeric acid (Re-COOH), as photodynamic therapy (PDT) photosensitizers. Re-NH₂ and Re-COOH proved to be excellent singlet oxygen generators in a lipophilic environment with quantum yields of about 75%. Furthermore, we envisaged to improve the selectivity of Re-COOH via conjugation to two types of peptides, namely a nuclear localization signal (NLS) and a derivative of the neuropeptide bombesin, to form Re-NLS and Re-Bombesin, respectively. Fluorescent microscopy on cervical cancer cells (HeLa) showed that the conjugation of Re-COOH to NLS significantly enhanced the compound's accumulation into the cell nucleus and more specifically into its nucleoli. Importantly, in view of PDT applications, the cytotoxicity of the Re complexes and their bioconjugates increased significantly upon light irradiation. In particular, Re-Bombesin was found to be at least 20-fold more toxic after light irradiation. DNA photo-cleavage studies demonstrated that all compounds damaged DNA via singlet oxygen and, to a minor extent, superoxide production. PMID:23982882

  4. In Vitro Selection of Cancer Cell-Specific Molecular Recognition Elements from Amino Acid Libraries

    PubMed Central

    Williams, Ryan M.; Sooter, Letha J.

    2015-01-01

    Differential cell systematic evolution of ligands by exponential enrichment (SELEX) is an in vitro selection method for obtaining molecular recognition elements (MREs) that specifically bind to individual cell types with high affinity. MREs are selected from initial large libraries of different nucleic or amino acids. This review outlines the construction of peptide and antibody fragment libraries as well as their different host types. Common methods of selection are also reviewed. Additionally, examples of cancer cell MREs are discussed, as well as their potential applications. PMID:26436100

  5. Quercetin Suppresses the Migration and Invasion in Human Colon Cancer Caco-2 Cells Through Regulating Toll-like Receptor 4/Nuclear Factor-kappa B Pathway

    PubMed Central

    Han, Mingyang; Song, Yucheng; Zhang, Xuedong

    2016-01-01

    Objective: The migration and invasion features, which were associated with inflammatory response, acted as vital roles in the development of colon cancer. Quercetin, a bioflavonoid compound, was widely spread in vegetables and fruits. Although quercetin exerts antioxidant and anticancer activities, the molecular signaling pathways in human colon cancer cells remain unclear. Hence, the present study was conducted to investigate the suppression of quercetin on migratory and invasive activity of colon cancer and the underlying mechanism. Materials and Methods: The effect of quercetin on cell viability, migration, and invasion of Caco-2 cells was analyzed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, wound-healing assay, and transwell chambers assay, respectively. The protein expressions of toll-like receptor 4 (TLR4), nuclear factor-kappa B (NF-κB) p65, mitochondrial membrane potential-2 (MMP-2), and MMP-9 were detected by Western blot assay. The inflammatory factors, such as tumor necrosis factor-α (TNF-α), cyclooxygenase-2 (Cox-2), and interleukin-6 (IL-6), in cell supernatant were detected by enzyme-linked immunosorbent assay. Results: The concentration of quercetin <20 μM was chosen for further experiments. Quercetin (5 μM) could remarkably suppress the migratory and invasive capacity of Caco-2 cells. The expressions of metastasis-related proteins of MMP-2, MMP-9 were decreased, whereas the expression of E-cadherin protein was increased by quercetin in a dose-dependent manner. Interestingly, the anti-TLR4 (2 μg) antibody or pyrrolidine dithiocarbamate (PDTC; 1 μM) could affect the inhibition of quercetin on cell migration and invasion, as well as the protein expressions of MMP-2, MMP-9, E-cadherin, TLR4, and NF-κB p65. In addition, quercetin could reduce the inflammation factors production of TNF-α, Cox-2, and IL-6. Conclusion: The findings suggested for the 1st time that quercetin might exert its anticolon cancer activity via

  6. Biomedical applications of SPION@APTES@PEG-folic acid@carboxylated quercetin nanodrug on various cancer cells

    NASA Astrophysics Data System (ADS)

    Akal, Z. Ü.; Alpsoy, L.; Baykal, A.

    2016-08-01

    In this study, carboxylated quercetin (CQ) was conjugated to superparamagnetic iron oxide nanoparticles (SPIONs) which were modified by (3-aminopropyl) triethoxysilane (APTES), Folic acid (FA) and carboxylated Polyethylene glycol (PEG); (SPION@APTES@FA-PEG@CQ), nanodrug has been synthesized via polyol and accompanying by various chemical synthesis routes. The characterization of the final product was done via X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Thermal gravimetric analysis (TGA), Transmission electron spectroscopy (TEM) and Vibrating sample magnetometer (VSM). Its cytotoxic and apoptotic activities on over expressed folic acid receptor (FR +) (MCF-7, HeLa) and none expressed folic acid receptor (FR-) (A549) cancer cell lines were determined by using MTT assay, Real-Time Cell Analysis, TUNEL assay, Annexin assay and RT-PCR analysis for Caspase3/7 respectively. SPION@APTES@FA-PEG@CQ nanodrug showed higher cytotoxicity against HeLa and MCF-7 cell lines as compared with A549 cell line. Moreover, SPION@APTES@FA-PEG@CQ nanodrug also caused higher apoptotic and necrotic effects in 100 μg/mL HeLa and MCF-7 cells than A549 cells. The findings showed that SPION@APTES@FA-PEG@CQ nanodrug has cytotoxic, apoptotic and necrotic effects on HeLa and MCF-7 which are FR over expressed cell lines and can be potentially used for the delivery of quercetin to cervical and breast cancer cells.

  7. Anti Proliferative and Pro Apoptotic Effects of Flavonoid Quercetin Are Mediated by CB1 Receptor in Human Colon Cancer Cell Lines.

    PubMed

    Refolo, Maria Grazia; D'Alessandro, Rosalba; Malerba, Natascia; Laezza, Chiara; Bifulco, Maurizio; Messa, Caterina; Caruso, Maria Gabriella; Notarnicola, Maria; Tutino, Valeria

    2015-12-01

    Quercetin, the major constituent of flavonoid and widely present in fruits and vegetables, is an attractive compound for cancer prevention due to its beneficial anti proliferative effects, showing a crucial role in the regulation of apoptosis and cell cycle signaling. In vitro studies have demonstrated that quercetin specifically influences colon cancer cell proliferation. Our experiments, using human colon adenocarcinoma cells, confirmed the anti proliferative effect of quercetin and gave intriguing new insight in to the knowledge of the mechanisms involved. We observed a significant increase in the expression of the endocannabinoids receptor (CB1-R) after quercetin treatment. CB1-R can be considered an estrogen responsive receptor and quercetin, having a structure similar to that of the estrogens, can interact with CB1-R leading to the regulation of cell growth. In order to clarify the contribution of the CB1-R to the quercetin action, we investigated some of the principal molecular pathways that are inhibited or activated by this natural compound. In particular we detected the inhibition of the major survival signals like the PI3K/Akt/mTOR and an induction of the pro apoptotic JNK/JUN pathways. Interestingly, the metabolism of β-catenin was modified by flavonoid both directly and through activated CB1-R. In all the experiments done, the quercetin action has proven to be reinforced by anandamide (Met-F-AEA), a CB1-R agonist, and partially counteracted by SR141716, a CB1-R antagonist. These findings open new perspectives for anticancer therapeutic strategies. PMID:25893829

  8. A neomorphic cancer cell-specific role of MAGE-A4 in trans-lesion synthesis

    PubMed Central

    Gao, Yanzhe; Mutter-Rottmayer, Elizabeth; Greenwalt, Alicia M.; Goldfarb, Dennis; Yan, Feng; Yang, Yang; Martinez-Chacin, Raquel C.; Pearce, Kenneth H.; Tateishi, Satoshi; Major, Michael B.; Vaziri, Cyrus

    2016-01-01

    Trans-lesion synthesis (TLS) is an important DNA-damage tolerance mechanism that permits ongoing DNA synthesis in cells harbouring damaged genomes. The E3 ubiquitin ligase RAD18 activates TLS by promoting recruitment of Y-family DNA polymerases to sites of DNA-damage-induced replication fork stalling. Here we identify the cancer/testes antigen melanoma antigen-A4 (MAGE-A4) as a tumour cell-specific RAD18-binding partner and an activator of TLS. MAGE-A4 depletion from MAGE-A4-expressing cancer cells destabilizes RAD18. Conversely, ectopic expression of MAGE-A4 (in cell lines lacking endogenous MAGE-A4) promotes RAD18 stability. DNA-damage-induced mono-ubiquitination of the RAD18 substrate PCNA is attenuated by MAGE-A4 silencing. MAGE-A4-depleted cells fail to resume DNA synthesis normally following ultraviolet irradiation and accumulate γH2AX, thereby recapitulating major hallmarks of TLS deficiency. Taken together, these results demonstrate a mechanism by which reprogramming of ubiquitin signalling in cancer cells can influence DNA damage tolerance and probably contribute to an altered genomic landscape. PMID:27377895

  9. A neomorphic cancer cell-specific role of MAGE-A4 in trans-lesion synthesis.

    PubMed

    Gao, Yanzhe; Mutter-Rottmayer, Elizabeth; Greenwalt, Alicia M; Goldfarb, Dennis; Yan, Feng; Yang, Yang; Martinez-Chacin, Raquel C; Pearce, Kenneth H; Tateishi, Satoshi; Major, Michael B; Vaziri, Cyrus

    2016-01-01

    Trans-lesion synthesis (TLS) is an important DNA-damage tolerance mechanism that permits ongoing DNA synthesis in cells harbouring damaged genomes. The E3 ubiquitin ligase RAD18 activates TLS by promoting recruitment of Y-family DNA polymerases to sites of DNA-damage-induced replication fork stalling. Here we identify the cancer/testes antigen melanoma antigen-A4 (MAGE-A4) as a tumour cell-specific RAD18-binding partner and an activator of TLS. MAGE-A4 depletion from MAGE-A4-expressing cancer cells destabilizes RAD18. Conversely, ectopic expression of MAGE-A4 (in cell lines lacking endogenous MAGE-A4) promotes RAD18 stability. DNA-damage-induced mono-ubiquitination of the RAD18 substrate PCNA is attenuated by MAGE-A4 silencing. MAGE-A4-depleted cells fail to resume DNA synthesis normally following ultraviolet irradiation and accumulate γH2AX, thereby recapitulating major hallmarks of TLS deficiency. Taken together, these results demonstrate a mechanism by which reprogramming of ubiquitin signalling in cancer cells can influence DNA damage tolerance and probably contribute to an altered genomic landscape. PMID:27377895

  10. Cancer stem cell-specific scavenger receptor CD36 drives glioblastoma progression

    PubMed Central

    Hale, James S.; Otvos, Balint; Sinyuk, Maksim; Alvarado, Alvaro G.; Hitomi, Masahiro; Stoltz, Kevin; Wu, Qiulian; Flavahan, William; Levison, Bruce; Johansen, Mette L.; Schmitt, David; Neltner, Janna M.; Huang, Ping; Ren, Bin; Sloan, Andrew E.; Silverstein, Roy L.; Gladson, Candece L.; DiDonato, Joseph A.; Brown, J. Mark; McIntyre, Thomas; Hazen, Stanley L.; Horbinski, Craig; Rich, Jeremy N.; Lathia, Justin D.

    2014-01-01

    Glioblastoma (GBM) contains a self-renewing, tumorigenic cancer stem cell (CSC) population which contributes to tumor propagation and therapeutic resistance. While the tumor microenvironment is essential to CSC self-renewal, the mechanisms by which CSCs sense and respond to microenvironmental conditions are poorly understood. Scavenger receptors are a broad class of membrane receptors that are well characterized on immune cells and instrumental in sensing apoptotic cellular debris and modified lipids. Here we provide evidence that CSCs selectively utilize the scavenger receptor CD36 to promote their maintenance using patient-derived CSCs and in vivo xenograft models. We detected CD36 expression in GBM cells in addition to previously described cell types including endothelial cells, macrophages and microglia. CD36 was enriched in CSCs and was able to functionally distinguish self-renewing cells. CD36 was co-expressed with integrin alpha 6 and CD133, previously described CSC markers, and CD36 reduction resulted in concomitant loss of integrin alpha 6 expression, self-renewal and tumor initiation capacity. We confirmed that oxidized phospholipids, ligands of CD36, were present in GBM and found that the proliferation of CSCs, but not non-CSCs, increased with exposure to oxidized low-density lipoprotein. CD36 was an informative biomarker of malignancy and negatively correlated to patient prognosis. These results provide a paradigm for CSCs to thrive by the selective enhanced expression of scavenger receptors, providing survival and metabolic advantages. PMID:24737733

  11. The effect of quercetin nanoparticle on cervical cancer progression by inducing apoptosis, autophagy and anti-proliferation via JAK2 suppression.

    PubMed

    Luo, Cheng-Lin; Liu, Yu-Qiong; Wang, Peng; Song, Chun-Hua; Wang, Kai-Juan; Dai, Li-Ping; Zhang, Jian-Ying; Ye, Hua

    2016-08-01

    Cervical cancer is a cause of cancer death, making it as the one of the most common cause for death among women globally. Though many studies before have explored a lot for cervical cancer prevention and treatment, there are still a lot far from to know based on the molecular mechanisms. Janus kinase 2 (JAK2) has been reported to play an essential role in the progression of apoptosis, autophagy and proliferation for cells. We loaded gold-quercetin into poly (dl-lactide-co-glycolide) nanoparticles to cervical cancer cells due to the propertities of quercetin in ameliorating cellular processes and the easier absorbance of nanoparticles. Here, in our study, quercetin nanoparticles (NQ) were administrated to cells to investigate the underlying mechanism by which the cervical cancer was regulated. First, JAK2-inhibited carvical cancer cell lines were involved for our experiments in vitro and in vivo. Western blotting, quantitative RT-PCR (qRT-PCR), ELISA, Immunohistochemistry, and flow-cytometric analysis were used to determine the key signaling pathway regulated by JAK2 for cervical cancer progression. And the role of quercetin nanoparticles was determined during the process. Data here indicated that JAK2, indeed, expressed highly in cancer cell lines compared to the normal cervical cells. And apoptosis and autophagy were found in JAK2-inhibited cancer cells through activating Caspase-3, and suppressing Cyclin-D1 and mTOR regulated by Signal Transducer and Activator of Transcription (STAT) 3/5 and phosphatidylinositide 3-kinase/protein kinases (PI3K/AKT) signaling pathway. The cervical cancer cells proliferation was inhibited. Further, tumor size and weight were reduced by inhibition of JAK2 in vivo experiments. Notably, administration with quercetin nanoparticles displayed similar role with JAK2 suppression, which could inhibit cervical cancer cells proliferation, invasion and migration. In addition, autophogy and apoptosis were induced, promoting cervical cancer cell

  12. Quercetin-loaded nanomicelles to circumvent human castration-resistant prostate cancer in vitro and in vivo

    NASA Astrophysics Data System (ADS)

    Zhao, Jing; Liu, Juan; Wei, Tuo; Ma, Xiaowei; Cheng, Qiang; Huo, Shuaidong; Zhang, Chunqiu; Zhang, Yanan; Duan, Xianglin; Liang, Xing-Jie

    2016-02-01

    Prostate cancer is highly prevalent and has become the second leading cause of cancer-related death in men. Its treatment remains a challenge in the clinic, particularly in patients who have advanced to ``castration-resistant prostate cancer'' (CRPC). Thus, more effective therapeutic strategies are required. Quercetin (QCT) is a natural flavonoid compound that has attracted increasing interest due to its anticancer activity. However, the clinical application of quercetin is largely hampered by its poor water solubility and low bioavailability. The objective of this study was to evaluate the therapeutic potential of novel QCT-loaded nanomicelles (M-QCTs) assembled from DSPE-PEG2000 for prostate cancer treatment. Our results indicated that QCT was efficiently encapsulated into micelles up to 1 mg mL-1, which corresponds to a 450-fold increase of its water solubility. In vitro studies showed that the half-maximal inhibitory concentration (IC50) value (20.2 μM) of M-QCTs was much lower than free QCT (>200 μM). Thus, M-QCTs were considerably more effective than free QCT in proliferation inhibition and apoptosis induction of human androgen-independent PC-3 cells. Furthermore, M-QCTs showed superior antitumor efficacy and the tumor proliferation rate reduced by 52.03% compared to the control group in the PC-3 xenograft mouse model, possibly due to increased accumulation of M-QCTs at the tumor site by the enhanced permeability and retention (EPR) effect. Collectively, our studies demonstrated that M-QCTs significantly increase drug accumulation at the tumor site and exhibit superior anticancer activity in prostate cancer. Thus, our nanomicelle-based drug delivery system constitutes a promising and effective therapeutic strategy for clinical treatment.Prostate cancer is highly prevalent and has become the second leading cause of cancer-related death in men. Its treatment remains a challenge in the clinic, particularly in patients who have advanced to ``castration

  13. Quercetin-loaded nanomicelles to circumvent human castration-resistant prostate cancer in vitro and in vivo

    NASA Astrophysics Data System (ADS)

    Zhao, Jing; Liu, Juan; Wei, Tuo; Ma, Xiaowei; Cheng, Qiang; Huo, Shuaidong; Zhang, Chunqiu; Zhang, Yanan; Duan, Xianglin; Liang, Xing-Jie

    2016-02-01

    Prostate cancer is highly prevalent and has become the second leading cause of cancer-related death in men. Its treatment remains a challenge in the clinic, particularly in patients who have advanced to ``castration-resistant prostate cancer'' (CRPC). Thus, more effective therapeutic strategies are required. Quercetin (QCT) is a natural flavonoid compound that has attracted increasing interest due to its anticancer activity. However, the clinical application of quercetin is largely hampered by its poor water solubility and low bioavailability. The objective of this study was to evaluate the therapeutic potential of novel QCT-loaded nanomicelles (M-QCTs) assembled from DSPE-PEG2000 for prostate cancer treatment. Our results indicated that QCT was efficiently encapsulated into micelles up to 1 mg mL-1, which corresponds to a 450-fold increase of its water solubility. In vitro studies showed that the half-maximal inhibitory concentration (IC50) value (20.2 μM) of M-QCTs was much lower than free QCT (>200 μM). Thus, M-QCTs were considerably more effective than free QCT in proliferation inhibition and apoptosis induction of human androgen-independent PC-3 cells. Furthermore, M-QCTs showed superior antitumor efficacy and the tumor proliferation rate reduced by 52.03% compared to the control group in the PC-3 xenograft mouse model, possibly due to increased accumulation of M-QCTs at the tumor site by the enhanced permeability and retention (EPR) effect. Collectively, our studies demonstrated that M-QCTs significantly increase drug accumulation at the tumor site and exhibit superior anticancer activity in prostate cancer. Thus, our nanomicelle-based drug delivery system constitutes a promising and effective therapeutic strategy for clinical treatment.Prostate cancer is highly prevalent and has become the second leading cause of cancer-related death in men. Its treatment remains a challenge in the clinic, particularly in patients who have advanced to ``castration

  14. Anti-Breast Cancer Potential of Quercetin via the Akt/AMPK/Mammalian Target of Rapamycin (mTOR) Signaling Cascade

    PubMed Central

    Rivera Rivera, Amilcar; Castillo-Pichardo, Linette; Gerena, Yamil; Dharmawardhane, Suranganie

    2016-01-01

    The Akt/adenosine monophosphate protein kinase (AMPK)/mammalian target of rapamycin (mTOR) pathway has emerged as a critical signaling nexus for regulating cellular metabolism, energy homeostasis, and cell growth. Thus, dysregulation of this pathway contributes to the development of metabolic disorders such as obesity, type 2diabetes, and cancer. We previously reported that a combination of grape polyphenols (resveratrol, quercetin and catechin: RQC), at equimolar concentrations, reduces breast cancer (BC) growth and metastasis in nude mice, and inhibits Akt and mTOR activities and activates AMPK, an endogenous inhibitor of mTOR, in metastatic BC cells. The objective of the present study was to determine the contribution of individual polyphenols to the effect of combined RQC on mTOR signaling. Metastatic BC cells were treated with RQC individually or in combination, at various concentrations, and the activities (phosphorylation) of AMPK, Akt, and the mTOR downstream effectors, p70S6 kinase (p70S6K) and 4E binding protein (4EBP1), were determined by Western blot. Results show that quercetin was the most effective compound for Akt/mTOR inhibition. Treatment with quercetin at 15μM had a similar effect as the RQC combination in the inhibition of BC cell proliferation, apoptosis, and migration. However, cell cycle analysis showed that the RQC treatment arrested BC cells in the G1 phase, while quercetin arrested the cell cycle in G2/M. In vivo experiments, using SCID mice with implanted tumors from metastatic BC cells, demonstrated that administration of quercetin at 15mg/kg body weight resulted in a ~70% reduction in tumor growth. In conclusion, quercetin appears to be a viable grape polyphenol for future development as an anti BC therapeutic. PMID:27285995

  15. Anti-Breast Cancer Potential of Quercetin via the Akt/AMPK/Mammalian Target of Rapamycin (mTOR) Signaling Cascade.

    PubMed

    Rivera Rivera, Amilcar; Castillo-Pichardo, Linette; Gerena, Yamil; Dharmawardhane, Suranganie

    2016-01-01

    The Akt/adenosine monophosphate protein kinase (AMPK)/mammalian target of rapamycin (mTOR) pathway has emerged as a critical signaling nexus for regulating cellular metabolism, energy homeostasis, and cell growth. Thus, dysregulation of this pathway contributes to the development of metabolic disorders such as obesity, type 2diabetes, and cancer. We previously reported that a combination of grape polyphenols (resveratrol, quercetin and catechin: RQC), at equimolar concentrations, reduces breast cancer (BC) growth and metastasis in nude mice, and inhibits Akt and mTOR activities and activates AMPK, an endogenous inhibitor of mTOR, in metastatic BC cells. The objective of the present study was to determine the contribution of individual polyphenols to the effect of combined RQC on mTOR signaling. Metastatic BC cells were treated with RQC individually or in combination, at various concentrations, and the activities (phosphorylation) of AMPK, Akt, and the mTOR downstream effectors, p70S6 kinase (p70S6K) and 4E binding protein (4EBP1), were determined by Western blot. Results show that quercetin was the most effective compound for Akt/mTOR inhibition. Treatment with quercetin at 15μM had a similar effect as the RQC combination in the inhibition of BC cell proliferation, apoptosis, and migration. However, cell cycle analysis showed that the RQC treatment arrested BC cells in the G1 phase, while quercetin arrested the cell cycle in G2/M. In vivo experiments, using SCID mice with implanted tumors from metastatic BC cells, demonstrated that administration of quercetin at 15mg/kg body weight resulted in a ~70% reduction in tumor growth. In conclusion, quercetin appears to be a viable grape polyphenol for future development as an anti BC therapeutic. PMID:27285995

  16. Quercetin metabolites inhibit MMP-2 expression in A549 lung cancer cells by PPAR-γ associated mechanisms.

    PubMed

    Chuang, Cheng-Hung; Yeh, Chiao-Lin; Yeh, Shu-Lan; Lin, En-Shyh; Wang, Li-Yu; Wang, Ying-Hsuna

    2016-07-01

    Our previous study demonstrated that quercetin-metabolite-enriched plasma (QP) but not quercetin itself upregulates peroxisome proliferator-activated receptor gamma (PPAR-γ) expression to induce G2/M arrest in A549 cells. In the present study, we incubated A549 cells with QP as well as quercetin-3-glucuronide (Q3G) and quercetin-3'-sulfate (Q3'S), two major metabolites of quercetin, to investigate the effects of quercetin metabolites on cell invasion and migration, the possible mechanisms and the role of PPAR-γ. We also compared the effects of QP with those of quercetin and troglitazone (TGZ), a PPAR-γ ligand. The results showed that QP significantly suppressed cell invasion and migration, as well as matrix metalloproteinases (MMPs)-2 activity and expression in a dose-dependent manner. The effects of 10% QP on those parameters were similar to those of 10μM quercetin and 20μM TGZ. However, QP and TGZ rather than quercetin itself increased the expressions of nm23-H1 and tissue inhibitor of metalloproteinase (TIMP-2). Furthermore, we demonstrated that Q3G and Q3'S also inhibited the protein expression of MMP-2. GW9662, a PPAR-γ antagonist, significantly diminished such an effect of Q3G and Q3'S. Silencing PPAR-γ expression in A549 cells also significantly diminished the suppression effect of Q3G and Q3'S on MMP-2 expression. Taken together, our study demonstrated that QP inhibited cell invasion and migration through nm23-H1/TIMP-2/MMP-2 associated mechanisms. The upregulation of PPAR-γ by quercetin metabolites such as Q3G and Q3'S could play an important role in the effects of QP. PMID:27260467

  17. The cranberry flavonoids PAC DP-9 and quercetin aglycone induce cytotoxicity and cell cycle arrest and increase cisplatin sensitivity in ovarian cancer cells.

    PubMed

    Wang, Yifei; Han, Alex; Chen, Eva; Singh, Rakesh K; Chichester, Clinton O; Moore, Richard G; Singh, Ajay P; Vorsa, Nicholi

    2015-05-01

    Cranberry flavonoids (flavonols and flavan-3-ols), in addition to their antioxidant properties, have been shown to possess potential in vitro activity against several cancers. However, the difficulty of isolating cranberry compounds has largely limited anticancer research to crude fractions without well-defined compound composition. In this study, individual cranberry flavonoids were isolated to the highest purity achieved so far using gravity and high performance column chromatography and LC-MS characterization. MTS assay indicated differential cell viability reduction of SKOV-3 and OVCAR-8 ovarian cancer cells treated with individual cranberry flavonoids. Treatment with quercetin aglycone and PAC DP-9, which exhibited the strongest activity, induced apoptosis, led to caspase-3 activation and PARP deactivation, and increased sensitivity to cisplatin. Furthermore, immunofluorescence microscopy and western blot study revealed reduced expression and activation of epidermal growth factor receptor (EGFR) in PAC DP-9 treated SKOV-3 cells. In addition, quercetin aglycone and PAC DP-9 deactivated MAPK-ERK pathway, induced downregulation of cyclin D1, DNA-PK, phospho-histone H3 and upregulation of p21, and arrested cell cycle progression. Overall, this study demonstrates promising in vitro cytotoxic and anti-proliferative properties of two newly characterized cranberry flavonoids, quercetin aglycone and PAC DP-9, against ovarian cancer cells. PMID:25776829

  18. The cranberry flavonoids PAC DP-9 and quercetin aglycone induce cytotoxicity and cell cycle arrest and increase cisplatin sensitivity in ovarian cancer cells

    PubMed Central

    WANG, YIFEI; HAN, ALEX; CHEN, EVA; SINGH, RAKESH K.; CHICHESTER, CLINTON O.; MOORE, RICHARD G.; SINGH, AJAY P.; VORSA, NICHOLI

    2015-01-01

    Cranberry flavonoids (flavonols and flavan-3-ols), in addition to their antioxidant properties, have been shown to possess potential in vitro activity against several cancers. However, the difficulty of isolating cranberry compounds has largely limited anticancer research to crude fractions without well-defined compound composition. In this study, individual cranberry flavonoids were isolated to the highest purity achieved so far using gravity and high performance column chromatography and LC-MS characterization. MTS assay indicated differential cell viability reduction of SKOV-3 and OVCAR-8 ovarian cancer cells treated with individual cranberry flavonoids. Treatment with quercetin aglycone and PAC DP-9, which exhibited the strongest activity, induced apoptosis, led to caspase-3 activation and PARP deactivation, and increased sensitivity to cisplatin. Furthermore, immunofluorescence microscopy and western blot study revealed reduced expression and activation of epidermal growth factor receptor (EGFR) in PAC DP-9 treated SKOV-3 cells. In addition, quercetin aglycone and PAC DP-9 deactivated MAPK-ERK pathway, induced downregulation of cyclin D1, DNA-PK, phosphohistone H3 and upregulation of p21, and arrested cell cycle progression. Overall, this study demonstrates promising in vitro cytotoxic and anti-proliferative properties of two newly characterized cranberry flavonoids, quercetin aglycone and PAC DP-9, against ovarian cancer cells. PMID:25776829

  19. Quercetin Aglycone Is Bioavailable in Murine Pancreas and Pancreatic Xenografts

    PubMed Central

    Zhang, Lifeng; Angst, Eliane; Park, Jenny L.; Moro, Aune; Dawson, David W.; Reber, Howard A.; Eibl, Guido; Hines, O. Joe; Go, Vay-Liang W.; Lu, Qing-Yi

    2010-01-01

    Quercetin is a potential chemopreventive and chemotherapeutic agent for pancreatic and other cancers. This study was to examine the distribution of quercetin in plasma, lung, liver, pancreas and pancreatic cancer xenografts in a murine in vivo model and the uptake of quercetin in pancreatic cancer MiaPaCa-2 cells in cellular in vitro model. Mice were randomly allocated to control diet, 0.2 and 1% quercetin diet groups utilizing the AIN93G-based diet (n=12 per group) for 6 weeks. In addition, 6 mice from each group were injected weekly with chemotherapeutic drug gemcitabine (120 mg/kg mouse, i.p.). MiaPaCa cells were collected from culture medium after cells were exposed to 30 µM of quercetin for 0.5, 1, 2, 4, 8, and 24 hrs. Levels of quercetin and 3-O’-methyl-quercetin in mice tissues and MiaPaCa-2 cells were measured by high-pressure liquid chromatography following enzymatic hydrolysis and then extraction. Our study showed that quercetin is accumulated in pancreatic cancer cells, and is absorbed in the circulating system, tumors and tissues of pancreas, liver and lung in vivo. A higher proportion of total quercetin found in tumors and pancreas are aglycones. Gemcitabine co-treatment with quercetin reduced absorption of quercetin in mice circulatory system and liver. Results from the study provide important information on the interpretation of chemo-therapeutic efficacy of quercetin. PMID:20499918

  20. Quercetin inhibits migration and invasion of SAS human oral cancer cells through inhibition of NF-κB and matrix metalloproteinase-2/-9 signaling pathways.

    PubMed

    Lai, Wan-Wen; Hsu, Shu-Chun; Chueh, Fu-Shih; Chen, Ya-Yin; Yang, Jai-Sing; Lin, Jing-Pin; Lien, Jin-Cherng; Tsai, Chung-Hung; Chung, Jing-Gung

    2013-05-01

    Quercetin, a principal flavanoid compound in onions, has been shown to possess a wide spectrum of pharmacological properties, including anticancer activities. Our earlier study showed that quercetin induced cytotoxic effects on SAS human oral cancer cells. In this study, we found that quercetin significantly reduced wound closure of SAS cells in culture plates after 12- and 24-h treatments. Results indicated that quercetin inhibited the expression and activity of matrix metalloproteinase (MMP)-2 and MMP-9, as measured by western blotting and gelatin zymography. The results from western blotting also showed that quercetin reduced the protein levels of MMP-2, -7, -9 and -10, vascular endothelial growth factor (VEGF), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) p65, inductible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), urokinase-type plasminogen activator (uPA), phosphatidylinositide-3 kinases (PI3K), nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (IKBα), IKB-α/β, phosphorylated nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor kinase, alpha/beta (p-IKKα/β), focal adhesion kinase (FAK), son of sevenless homolog-1 (SOS1), growth factor receptor-bound protein-2 (GRB2), mitogen-activated protein kinase kinase kinase-3 (MEKK3), MEKK7, extracellular-signal-regulated kinase 1/2 (ERK1/2), p-ERK1/2, c-Jun N-terminal kinase 1/2 (JNK1/2), p38, p-p38, Jun proto-oncogene (c-JUN) and p-c-JUN but it did not affect Ras homolog gene family, member A (RhoA), Protein kinase C (PKC) and rat sarcoma viral oncogene homolog (RAS) in SAS cells. Confocal laser microscopy also showed that quercetin promoted the expressions of RhoA and Rho-associated, coiled-coil containing protein kinase-1 (ROCK1), but inhibited the expression of NF-κB p65 in SAS cells. It is concluded from these data that inhibition of migration and invasion of SAS cells by quercetin is associated with the down

  1. Sulforaphane, quercetin and catechins complement each other in elimination of advanced pancreatic cancer by miR-let-7 induction and K-ras inhibition

    PubMed Central

    APPARI, MAHESH; BABU, KAMESH R.; KACZOROWSKI, ADAM; GROSS, WOLFGANG; HERR, INGRID

    2014-01-01

    Pancreatic ductal adenocarcinoma (PDA) has the worst prognosis of all malignancies, and current therapeutic options do not target cancer stem cells (CSCs), which may be the reason for the extreme aggressiveness. The dietary agents sulforaphane and quercetin enriched e.g., in broccoli, and the main and best studied green tea catechin EGCG hold promise as anti-CSC agents in PDA. We examined the efficacy of additional catechins and the combination of these bioactive agents to stem cell features and miRNA signaling. Two established and one primary PDA cell line and non-malignant pancreatic ductal cells were used. Whereas each agent strongly inhibited colony formation, the catechins ECG and CG were more effective than EGCG. A mixture of green tea catechins (GTCs) significantly inhibited viability, migration, expression of MMP-2 and -9, ALDH1 activity, colony and spheroid formation and induced apoptosis, but the combination of GTCs with sulforaphane or quercetin was superior. Following treatment with bioactive agents, the expression of miR-let7-a was specifically induced in cancer cells but not in normal cells and it was associated with K-ras inhibition. These data demonstrate that sulforaphane, quercetin and GTC complement each other in inhibition of PDA progression by induction of miR-let7-a and inhibition of K-ras. PMID:25017900

  2. Anthracycline Drugs on Modified Surface of Quercetin-Loaded Polymer Nanoparticles: A Dual Drug Delivery Model for Cancer Treatment

    PubMed Central

    Saha, Chabita; Kaushik, Agrima; Das, Asmita; Pal, Sandip; Majumder, Debashis

    2016-01-01

    Polymer nanoparticles are vehicles used for delivery of hydrophobic anti-cancer drugs, like doxorubicin, paclitaxel or chemopreventors like quercetin (Q). The present study deals with the synthesis and characterisation of nano formulations (NFs) from Q loaded PLGA (poly lactic-co-glycolic acid) nano particles (NPs) by surface modification. The surface of Q-loaded (NPs) is modified by coating with biopolymers like bovine serum albumin (BSA) or histones (His). Conventional chemotherapeutic drugs adriamycin (ADR) and mitoxantrone (MTX) are bound to BSA and His respectively before being coated on Q-loaded NPs to nano formulate NF1 and NF2 respectively. The sizes of these NFs are in the range 400–500 nm as ascertained by SEM and DLS measurements. Encapsulation of Q in polymer NPs is confirmed from shifts in FT-IR, TGA and DSC traces of Q-loaded NPs compared to native PLGA and Q. Surface modification in NFs is evidenced by three distinct regions in their TEM images; the core, polymer capsule and the coated surface. Negative zeta potential of Q-loaded NPs shifted to positive potential on surface modification in NF1 and NF2. In vitro release of Q from the NFs lasted up to twenty days with an early burst release. NF2 is better formulation than NF1 as loading of MTX is 85% compared to 23% loading of ADR. Such NFs are expected to overcome multi-drug resistance (MDR) by reaching and treating the target cancerous cells by virtue of size, charge and retention. PMID:27196562

  3. Quercetin and epigallocatechin gallate inhibit glucose uptake and metabolism by breast cancer cells by an estrogen receptor-independent mechanism

    SciTech Connect

    Moreira, Liliana; Araújo, Isabel; Costa, Tito; Correia-Branco, Ana; Faria, Ana; Martel, Fátima; Keating, Elisa

    2013-07-15

    In this study we characterized {sup 3}H-2-deoxy-D-glucose ({sup 3}H -DG) uptake by the estrogen receptor (ER)-positive MCF7 and the ER-negative MDA-MB-231 human breast cancer cell lines and investigated the effect of quercetin (QUE) and epigallocatechin gallate (EGCG) upon {sup 3}H-DG uptake, glucose metabolism and cell viability and proliferation. In both MCF7 and MDA-MB-231 cells {sup 3}H-DG uptake was (a) time-dependent, (b) saturable with similar capacity (V{sub max}) and affinity (K{sub m}), (c) potently inhibited by cytochalasin B, an inhibitor of the facilitative glucose transporters (GLUT), (d) sodium-independent and (e) slightly insulin-stimulated. This suggests that {sup 3}H-DG uptake by both cell types is mediated by members of the GLUT family, including the insulin-responsive GLUT4 or GLUT12, while being independent of the sodium-dependent glucose transporter (SGLT1). QUE and EGCG markedly and concentration-dependently inhibited {sup 3}H-DG uptake by MCF7 and by MDA-MB-231 cells, and both compounds blocked lactate production by MCF7 cells. Additionally, a 4 h-treatment with QUE or EGCG decreased MCF7 cell viability and proliferation, an effect that was more potent when glucose was available in the extracellular medium. Our results implicate QUE and EGCG as metabolic antagonists in breast cancer cells, independently of estrogen signalling, and suggest that these flavonoids could serve as therapeutic agents/adjuvants even for ER-negative breast tumors. -- Highlights: • Glucose uptake by MCF7 and MDA-MB-231 cells is mainly mediated by GLUT1. • QUE and EGCG inhibit cellular glucose uptake thus abolishing the Warburg effect. • This process induces cytotoxicity and proliferation arrest in MCF7 cells. • The flavonoids’ effects are independent of estrogen receptor signalling.

  4. Anthracycline Drugs on Modified Surface of Quercetin-Loaded Polymer Nanoparticles: A Dual Drug Delivery Model for Cancer Treatment.

    PubMed

    Saha, Chabita; Kaushik, Agrima; Das, Asmita; Pal, Sandip; Majumder, Debashis

    2016-01-01

    Polymer nanoparticles are vehicles used for delivery of hydrophobic anti-cancer drugs, like doxorubicin, paclitaxel or chemopreventors like quercetin (Q). The present study deals with the synthesis and characterisation of nano formulations (NFs) from Q loaded PLGA (poly lactic-co-glycolic acid) nano particles (NPs) by surface modification. The surface of Q-loaded (NPs) is modified by coating with biopolymers like bovine serum albumin (BSA) or histones (His). Conventional chemotherapeutic drugs adriamycin (ADR) and mitoxantrone (MTX) are bound to BSA and His respectively before being coated on Q-loaded NPs to nano formulate NF1 and NF2 respectively. The sizes of these NFs are in the range 400-500 nm as ascertained by SEM and DLS measurements. Encapsulation of Q in polymer NPs is confirmed from shifts in FT-IR, TGA and DSC traces of Q-loaded NPs compared to native PLGA and Q. Surface modification in NFs is evidenced by three distinct regions in their TEM images; the core, polymer capsule and the coated surface. Negative zeta potential of Q-loaded NPs shifted to positive potential on surface modification in NF1 and NF2. In vitro release of Q from the NFs lasted up to twenty days with an early burst release. NF2 is better formulation than NF1 as loading of MTX is 85% compared to 23% loading of ADR. Such NFs are expected to overcome multi-drug resistance (MDR) by reaching and treating the target cancerous cells by virtue of size, charge and retention. PMID:27196562

  5. B-cell-specific Moloney murine leukemia virus integration site 1: potential stratification factor and therapeutic target for epithelial ovarian cancer.

    PubMed

    Zhao, Qianying; Gui, Ting; Qian, Qiuhong; Li, Lei; Shen, Keng

    2016-01-01

    Epithelial ovarian cancer, a vexing challenge for clinical management, still lacks biomarkers for early diagnosis, precise stratification, and prognostic evaluation of patients. B-cell-specific Moloney murine leukemia virus integration site 1 (BMI1), a member of the polycomb group of proteins, engages in diverse cellular processes, including proliferation, differentiation, senescence, and stem cell renewal. In addition, BMI1, as a cancer stem-cell marker, participates in tumorigenesis through various pathways. Rewardingly, recent studies have also revealed a relationship between BMI1 expression and the clinical grade/stage, therapy response, and survival outcome in a majority of human malignancies, including epithelial ovarian cancer. Therefore, BMI1 might serve as a potential stratification factor and treatment target for epithelial ovarian cancer, pending evidence from further investigations. PMID:27578986

  6. B-cell-specific Moloney murine leukemia virus integration site 1: potential stratification factor and therapeutic target for epithelial ovarian cancer

    PubMed Central

    Zhao, Qianying; Gui, Ting; Qian, Qiuhong; Li, Lei; Shen, Keng

    2016-01-01

    Epithelial ovarian cancer, a vexing challenge for clinical management, still lacks biomarkers for early diagnosis, precise stratification, and prognostic evaluation of patients. B-cell-specific Moloney murine leukemia virus integration site 1 (BMI1), a member of the polycomb group of proteins, engages in diverse cellular processes, including proliferation, differentiation, senescence, and stem cell renewal. In addition, BMI1, as a cancer stem-cell marker, participates in tumorigenesis through various pathways. Rewardingly, recent studies have also revealed a relationship between BMI1 expression and the clinical grade/stage, therapy response, and survival outcome in a majority of human malignancies, including epithelial ovarian cancer. Therefore, BMI1 might serve as a potential stratification factor and treatment target for epithelial ovarian cancer, pending evidence from further investigations. PMID:27578986

  7. The dietary bioflavonoid quercetin synergizes with epigallocathechin gallate (EGCG) to inhibit prostate cancer stem cell characteristics, invasion, migration and epithelial-mesenchymal transition

    PubMed Central

    2010-01-01

    Background Much attention has been recently focused on the role of cancer stem cells (CSCs) in the initiation and progression of solid malignancies. Since CSCs are able to proliferate and self-renew extensively due to their ability to express anti-apoptotic and drug resistant proteins, thus sustaining tumor growth. Therefore, the strategy to eradicate CSCs might have significant clinical implications. The objectives of this study were to examine the molecular mechanisms by which epigallocathechin gallate (EGCG) inhibits stem cell characteristics of prostate CSCs, and synergizes with quercetin, a major polyphenol and flavonoid commonly detected in many fruits and vegetables. Results Our data indicate that human prostate cancer cell lines contain a small population of CD44+CD133+ cancer stem cells and their self-renewal capacity is inhibited by EGCG. Furthermore, EGCG inhibits the self-renewal capacity of CD44+α2β1+CD133+ CSCs isolated from human primary prostate tumors, as measured by spheroid formation in suspension. EGCG induces apoptosis by activating capase-3/7 and inhibiting the expression of Bcl-2, survivin and XIAP in CSCs. Furthermore, EGCG inhibits epithelial-mesenchymal transition by inhibiting the expression of vimentin, slug, snail and nuclear β-catenin, and the activity of LEF-1/TCF responsive reporter, and also retards CSC's migration and invasion, suggesting the blockade of signaling involved in early metastasis. Interestingly, quercetin synergizes with EGCG in inhibiting the self-renewal properties of prostate CSCs, inducing apoptosis, and blocking CSC's migration and invasion. These data suggest that EGCG either alone or in combination with quercetin can eliminate cancer stem cell-characteristics. Conclusion Since carcinogenesis is a complex process, combination of bioactive dietary agents with complementary activities will be beneficial for prostate cancer prevention and/ortreatment. PMID:20718984

  8. Absence of initiating activity by quercetin in the rat liver.

    PubMed

    Kato, K; Mori, H; Tanaka, T; Fujii, M; Kawai, T; Nishikawa, A; Takahashi, M; Hirono, I

    1985-08-01

    Initiating activity of quercetin was tested in rats which were treated with partial hepatectomy and given a liver cancer promoter, phenobarbital. A few intestinal neoplasms were seen but without significant difference in incidence from those in the quercetin-untreated group. Moreover, neither neoplastic nor preneoplastic liver changes were detected in quercetin-treated groups. With hepatocyte primary culture/DNA repair test, quercetin did not produce genotoxicity. The results show that quercetin has no initiating or genotoxic activities in the rat liver. PMID:4029060

  9. Selenium-containing chrysin and quercetin derivatives: attractive scaffolds for cancer therapy.

    PubMed

    Martins, Inês L; Charneira, Catarina; Gandin, Valentina; Ferreira da Silva, João L; Justino, Gonçalo C; Telo, João P; Vieira, Abel J S C; Marzano, Cristina; Antunes, Alexandra M M

    2015-05-28

    Selenium-containing chrysin (SeChry) and 3,7,3',4'-tetramethylquercetin (SePQue) derivatives were synthesized by a microwave-based methodology. In addition to their improvement in terms of DPPH scavenging and potential GPx-like activities, when tested in a panel of cancer cell lines both selenium-derivatives revealed consistently to be more cytotoxic when compared with their oxo and thio-analogues, evidencing the key role of selenocabonyl moiety for these activities. In particular, SeChry elicited a noteworthy cytotoxic activity with mean IC50 values 18- and 3-fold lower than those observed for chrysin and cisplatin, respectively. Additionally, these seleno-derivatives evidenced an ability to overcome cisplatin and multidrug resistance. Notably, a differential behavior toward malignant and nonmalignant cells was observed for SeChry and SePQue, exhibiting higher selectivity indexes when compared with the chalcogen-derivatives and cisplatin. Our preliminary investigation on the mechanism of cytotoxicity of SeChry and SePQue in MCF-7 human mammary cancer cells demonstrated their capacity to efficiently suppress the clonal expansion along with their ability to hamper TrxR activity leading to apoptotic cell death. PMID:25906385

  10. Quercetin, Inflammation and Immunity

    PubMed Central

    Li, Yao; Yao, Jiaying; Han, Chunyan; Yang, Jiaxin; Chaudhry, Maria Tabassum; Wang, Shengnan; Liu, Hongnan; Yin, Yulong

    2016-01-01

    In vitro and some animal models have shown that quercetin, a polyphenol derived from plants, has a wide range of biological actions including anti-carcinogenic, anti-inflammatory and antiviral activities; as well as attenuating lipid peroxidation, platelet aggregation and capillary permeability. This review focuses on the physicochemical properties, dietary sources, absorption, bioavailability and metabolism of quercetin, especially main effects of quercetin on inflammation and immune function. According to the results obtained both in vitro and in vivo, good perspectives have been opened for quercetin. Nevertheless, further studies are needed to better characterize the mechanisms of action underlying the beneficial effects of quercetin on inflammation and immunity. PMID:26999194

  11. Quercetin, Inflammation and Immunity.

    PubMed

    Li, Yao; Yao, Jiaying; Han, Chunyan; Yang, Jiaxin; Chaudhry, Maria Tabassum; Wang, Shengnan; Liu, Hongnan; Yin, Yulong

    2016-03-01

    In vitro and some animal models have shown that quercetin, a polyphenol derived from plants, has a wide range of biological actions including anti-carcinogenic, anti-inflammatory and antiviral activities; as well as attenuating lipid peroxidation, platelet aggregation and capillary permeability. This review focuses on the physicochemical properties, dietary sources, absorption, bioavailability and metabolism of quercetin, especially main effects of quercetin on inflammation and immune function. According to the results obtained both in vitro and in vivo, good perspectives have been opened for quercetin. Nevertheless, further studies are needed to better characterize the mechanisms of action underlying the beneficial effects of quercetin on inflammation and immunity. PMID:26999194

  12. The flavonoid quercetin induces cell cycle arrest and mitochondria-mediated apoptosis in human cervical cancer (HeLa) cells through p53 induction and NF-κB inhibition.

    PubMed

    Vidya Priyadarsini, R; Senthil Murugan, R; Maitreyi, S; Ramalingam, K; Karunagaran, D; Nagini, S

    2010-12-15

    With increasing use of plant-derived cancer chemotherapeutic agents, exploring the antiproliferative effects of phytochemicals has gained increasing momentum for anticancer drug design. The dietary phytochemical quercetin, modulates several signal transduction pathways associated with cell proliferation and apoptosis. The present study was undertaken to examine the effect of quercetin on cell viability, and to determine the molecular mechanism of quercetin-induced cell death by investigating the expression of Bcl-2 family proteins (Bcl-2, Bcl-xL, Mcl1, Bax, Bad, p-Bad), cytochrome C, Apaf-1, caspases, and survivin as well as the cell cycle regulatory proteins (p53, p21, cyclin D1), and NF-κB family members (p50, p65, IκB, p-IκB-α, IKKβ and ubiquitin ligase) in human cervical cancer (HeLa) cells. The results demonstrate that quercetin suppressed the viability of HeLa cells in a dose-dependent manner by inducing G2/M phase cell cycle arrest and mitochondrial apoptosis through a p53-dependent mechanism. This involved characteristic changes in nuclear morphology, phosphatidylserine externalization, mitochondrial membrane depolarization, modulation of cell cycle regulatory proteins and NF-κB family members, upregulation of proapoptotic Bcl-2 family proteins, cytochrome C, Apaf-1 and caspases, and downregulation of antiapoptotic Bcl-2 proteins and survivin. Quercetin that exerts opposing effects on different signaling networks to inhibit cancer progression is a classic candidate for anticancer drug design. PMID:20858478

  13. The quercetin paradox

    SciTech Connect

    Boots, Agnes W. . E-mail: a.boots@farmaco.unimaas.nl; Li, Hui; Schins, Roel P.F.; Duffin, Rodger; Heemskerk, Johan W.M.; Bast, Aalt; Haenen, Guido R.M.M.

    2007-07-01

    Free radical scavenging antioxidants, such as quercetin, are chemically converted into oxidation products when they protect against free radicals. The main oxidation product of quercetin, however, displays a high reactivity towards thiols, which can lead to the loss of protein function. The quercetin paradox is that in the process of offering protection, quercetin is converted into a potential toxic product. In the present study, this paradox is evaluated using rat lung epithelial (RLE) cells. It was found that quercetin efficiently protects against H{sub 2}O{sub 2}-induced DNA damage in RLE cells, but this damage is swapped for a reduction in GSH level, an increase in LDH leakage as well as an increase of the cytosolic free calcium concentration. To our knowledge, this is the first study that indicates that the quercetin paradox, i.e. the exchange of damage caused by quercetin and its metabolites, also occurs in living lung cells. Following depletion of GSH in the cells by BSO pre-treatment, this quercetin paradox becomes more pronounced, confirming that the formation of thiol reactive quercetin metabolites is involved in the quercetin paradox. The quercetin paradox in living cells implies that the anti-oxidant directs oxidative damage selectively to thiol arylation. Apparently, the potential toxicity of metabolites formed during the actual antioxidant activity of free radical scavengers should be considered in antioxidant supplementation.

  14. The prognostic value of polycomb group protein B-cell-specific moloney murine leukemia virus insertion site 1 in stage II colon cancer patients.

    PubMed

    Espersen, Maiken L M; Linnemann, Dorte; Christensen, Ib J; Alamili, Mahdi; Troelsen, Jesper T; Høgdall, Estrid

    2016-07-01

    The aim of this study was to investigate the prognostic value of B-cell-specific moloney murine leukemia virus insertion site 1 (BMI1) protein expression in primary tumors of stage II colon cancer patients. BMI1 protein expression was assessed by immunohistochemistry in a retrospective patient cohort consisting of 144 stage II colon cancer patients. BMI1 expression at the invasive front of the primary tumors correlated with mismatch repair status of the tumors. Furthermore, BMI1 expression at the luminal surface correlated with T-stage, tumor location, and the histological subtypes of the tumors. In a univariate Cox proportional hazard analysis, no statistical significant association between risk of relapse and BMI1 protein expression at the invasive front (HR: 1.12; 95% CI 0.78-1.60; p = 0.53) or at the luminal surface of the tumor (HR: 1.06; 95% CI 0.75-1.48; p = 0.70) was found. Likewise, there was no association between 5-year overall survival and BMI1 expression at the invasive front (HR: 1.12; 95% CI 0.80-1.56; p = 0.46) or at the luminal surface of the tumor (HR: 1.16; 95% CI 0.86-1.60; p = 0.33). In conclusion, BMI1 expression in primary tumors of stage II colon cancer patients could not predict relapse or overall survival of the patients, thus having a limited prognostic value in stage II colon cancer patients. PMID:27102362

  15. Increased cytosine DNA-methyltransferase activity is target-cell-specific and an early event in lung cancer.

    PubMed Central

    Belinsky, S A; Nikula, K J; Baylin, S B; Issa, J P

    1996-01-01

    The association between increased DNA-methyltransferase (DNA-MTase) activity and tumor development suggest a fundamental role for this enzyme in the initiation and progression of cancer. A true functional role for DNA-MTase in the neoplastic process would be further substantiated if the target cells affected by the initiating carcinogen exhibit changes in enzyme activity. This hypothesis was addressed by examining DNA-MTase activity in alveolar type II (target) and Clara (nontarget) cells from A/J and C3H mice that exhibit high and low susceptibility, respectively, for lung tumor formation. Increased DNA-MTase activity was found only in the target alveolar type II cells of the susceptible A/J mouse and caused a marked increase in overall DNA methylation in these cells. Both DNA-MTase and DNA methylation changes were detected 7 days after carcinogen exposure and, thus, were early events in neoplastic evolution. Increased gene expression was also detected by RNA in situ hybridization in hypertrophic alveolar type II cells of carcinogen-treated A/J mice, indicating that elevated levels of expression may be a biomarker for premalignancy. Enzyme activity increased incrementally during lung cancer progression and coincided with increased expression of the DNA-MTase activity are strongly associated with neoplastic development and constitute a key step in carcinogenesis. The detection of premalignant lung disease through increased DNA-MTase expression and the possibility of blocking the deleterious effects of this change with specific inhibitors will offer new intervention strategies for lung cancer. Images Fig. 2 PMID:8633014

  16. Quercetin-induced apoptosis prevents EBV infection

    PubMed Central

    Lee, Minjung; Son, Myoungki; Ryu, Eunhyun; Shin, Yu Su; Kim, Jong Gwang; Kang, Byung Woog; Sung, Gi-Ho; Cho, Hyosun; Kang, Hyojeung

    2015-01-01

    Epstein-Barr virus (EBV) is a human gamma-1 herpesvirus that establishes a lifelong latency in over 90% of the world's population. During latency, virus exists predominantly as a chromatin-associated, multicopy episome in the nuclei of a variety of tumor cells derived from B cells, T cells, natural killer (NK) cells, and epithelial cells. Licorice is the root of Glycyrrhiza uralensis or G. glabra that has traditionally cultivated in eastern part of Asia. Licorice was reported to have anti-viral, anti-inflammatory, anti-atopic, hepatoprotective, anti-neurodegenerative, anti-tumor, anti-diabetic effects and so forth. Quercetin and isoliquiritigenin are produced from licorice and highly similar in molecular structure. They have diverse bioactive effects such as antiviral activity, anti-asthmatic activity, anti-cancer activity, anti-inflammation activity, monoamine-oxidase inhibitor, and etc. To determine anti-EBV and anti-EBVaGC (Epstein-Barr virus associated gastric carcinoma) effects of licorice, we investigated antitumor and antiviral effects of quercetin and isoliquiritigenin against EBVaGC. Although both quercetin and isoliquiritigenin are cytotoxic to SNU719 cells, quercetin induced more apoptosis in SNU719 cells than isoliquiritigenin, more completely eliminated DNMT1 and DNMT3A expressions than isoliquiritigenin, and more strongly affects the cell cycle progression of SNU719 than isoliquiritigenin. Both quercetin and isoliquiritigenin induce signal transductions to stimulate apoptosis, and induce EBV gene transcription. Quercetin enhances frequency of F promoter use, whereas isoliquiritigenin enhances frequency of Q promoter use. Quercetin reduces EBV latency, whereas isoliquiritigenin increases the latency. Quercetin increases more the EBV progeny production, and inhibits more EBV infection than isoliquiritigenin. These results indicate that quercetin could be a promising candidate for antiviral and antitumor agents against EBV and human gastric carcinoma

  17. Application of Bioactive Quercetin in Oncotherapy: From Nutrition to Nanomedicine.

    PubMed

    Nam, Ju-Suk; Sharma, Ashish Ranjan; Nguyen, Lich Thi; Chakraborty, Chiranjib; Sharma, Garima; Lee, Sang-Soo

    2016-01-01

    Phytochemicals as dietary constituents are being explored for their cancer preventive properties. Quercetin is a major constituent of various dietary products and recently its anti-cancer potential has been extensively explored, revealing its anti-proliferative effect on different cancer cell lines, both in vitro and in vivo. Quercetin is known to have modulatory effects on cell apoptosis, migration and growth via various signaling pathways. Though, quercetin possesses great medicinal value, its applications as a therapeutic drug are limited. Problems like low oral bioavailability and poor aqueous solubility make quercetin an unreliable candidate for therapeutic purposes. Additionally, the rapid gastrointestinal digestion of quercetin is also a major barrier for its clinical translation. Hence, to overcome these disadvantages quercetin-based nanoformulations are being considered in recent times. Nanoformulations of quercetin have shown promising results in its uptake by the epithelial system as well as enhanced delivery to the target site. Herein we have tried to summarize various methods utilized for nanofabrication of quercetin formulations and for stable and sustained delivery of quercetin. We have also highlighted the various desirable measures for its use as a promising onco-therapeutic agent. PMID:26797598

  18. Cytoplasmic Delivery of Liposomes into MCF-7 Breast Cancer Cells Mediated by Cell-Specific Phage Fusion Coat Protein

    PubMed Central

    Wang, Tao; Yang, Shenghong; Petrenko, Valery A; Torchilin, Vladimir P

    2010-01-01

    Earlier, we have shown that doxorubicin-loaded liposomes (Doxil) modified with a chimeric phage fusion coat protein specific towards MCF-7 breast cancer cells identified from a phage landscape library demonstrated a significantly enhanced association with target cells and an increased cytotoxicity. Based on some structural similarities between the N-terminus of the phage potein and known fusogenic peptides, we hypothesized that, in addition to the specific targeting, the phage protein may possess endosome-escaping potential and an increased cytotoxicity of drug-loaded phage protein-targeted liposomes may be explained by an advantageous combination of both, cell targeting and endosomal escape of drug-loaded nanocarrier. The use of the fluorescence resonance energy transfer (FRET) technique allowed us to clearly demonstrate the pH-dependent membrane fusion activity of the phage protein. Endosomal escape and cytosolic delivery of phage-liposomes was visualized with fluorescence microscopy. Endosome acidification inhibition by bafilomycin A 1 resulted in decreased cytotoxicity of the phage-Doxil, while the endosome disruption by chloroquine had a negligible effect on efficacy of phage-Doxil, confirming its endosomal escape. Our results demonstrated an endosome-escaping property of the phage protein and provided an insight on mechanism of the enhanced cytotoxicity of phage-Doxil. PMID:20438086

  19. Influenza virus infection elicits protective antibodies and T cells specific for host cell antigens also expressed as tumor-associated antigens: a new view of cancer immunosurveillance.

    PubMed

    Iheagwara, Uzoma K; Beatty, Pamela L; Van, Phu T; Ross, Ted M; Minden, Jonathan S; Finn, Olivera J

    2014-03-01

    Most tumor-associated antigens (TAA) are self-molecules that are abnormally expressed in cancer cells and become targets of antitumor immune responses. Antibodies and T cells specific for some TAAs have been found in healthy individuals and are associated with lowered lifetime risk for developing cancer. Lower risk for cancer has also been associated with a history of febrile viral diseases. We hypothesized that virus infections could lead to transient expression of abnormal forms of self-molecules, some of which are TAAs; facilitated by the adjuvant effects of infection and inflammation, these molecules could elicit specific antibodies, T cells, and lasting immune memory simultaneously with immunity against viral antigens. Such infection-induced immune memory for TAA would be expected to provide life-long immune surveillance of cancer. Using influenza virus infection in mice as a model system, we tested this hypothesis and demonstrated that influenza-experienced mice control 3LL mouse lung tumor challenge better than infection-naive control mice. Using 2D-difference gel electrophoresis and mass spectrometry, we identified numerous molecules, some of which are known TAAs, on the 3LL tumor cells recognized by antibodies elicited by two successive influenza infections. We studied in detail immune responses against glyceraldehyde-3-phosphate dehydrogenase (GAPDH), histone H4, HSP90, malate dehydrogenase 2, and annexin A2, all of which were overexpressed in influenza-infected lungs and in tumor cells. Finally, we show that immune responses generated through vaccination against peptides derived from these antigens correlated with improved tumor control. PMID:24778322

  20. Sensitization of androgen refractory prostate cancer cells to anti-androgens through re-expression of epigenetically repressed androgen receptor - Synergistic action of quercetin and curcumin.

    PubMed

    Sharma, Vikas; Kumar, Lokesh; Mohanty, Sujit K; Maikhuri, Jagdamba P; Rajender, Singh; Gupta, Gopal

    2016-08-15

    Epigenetic repression of Androgen Receptor (AR) gene by hypermethylation of its promoter causes resistance in prostate cancer (CaP) to androgen deprivation therapy with anti-androgens. Some dietary phytocompounds like quercetin (Q) and curcumin (C) with reported DNMT-inhibitory activity were tested for their ability to re-express the AR in AR-negative CaP cell lines PC3 and DU145. Combined treatment with Q+C was much more effective than either Q or C in inhibiting DNMT, causing global hypomethylation, restoring AR mRNA and protein levels and causing apoptosis via mitochondrial depolarization of PC3 and DU145. The functional AR protein expressed in Q+C treated cells sensitized them to dihydrotestosterone (DHT)-induced proliferation, bicalutamide-induced apoptosis, bound to androgen response element to increase luciferase activity in gene reporter assay and was susceptible to downregulation by AR siRNA. Bisulfite sequencing revealed high methylation of AR promoter CpG sites in AR-negative DU145 and PC3 cell lines that was significantly demethylated by Q+C treatment, which restored AR expression. Notable synergistic effects of Q+C combination in re-sensitizing androgen refractory CaP cells to AR-mediated apoptosis, their known safety in clinical use, and epidemiological evidences relating their dietary consumption with lower cancer incidences indicate their potential for use in chemoprevention of androgen resistance in prostate cancer. PMID:27132804

  1. LMO7 Mediates Cell-Specific Activation of the Rho-Myocardin-Related Transcription Factor-Serum Response Factor Pathway and Plays an Important Role in Breast Cancer Cell Migration ▿

    PubMed Central

    Hu, Qiande; Guo, Chun; Li, Yali; Aronow, Bruce J.; Zhang, Jinsong

    2011-01-01

    Serum response factor (SRF) is a ubiquitously expressed transcription factor that regulates cell-specific functions such as muscle development and breast cancer metastasis. The myocardin-related transcription factors (MRTFs), which are transcriptional coactivators mediating cell-specific functions of SRF, are also ubiquitously expressed. How MRTFs and SRF drive cell-specific transcription is still not fully understood. Here we show that LIM domain only 7 (LMO7) is a cell-specific regulator of MRTFs and plays an important role in breast cancer cell migration. LMO7 activates MRTFs by relieving actin-mediated inhibition in a manner that requires, and is synergistic with, Rho GTPase. Whereas Rho is required for LMO7 to activate full-length MRTFs that have three RPEL actin-binding motifs, the disruption of individual actin-RPEL interactions is sufficient to eliminate the Rho dependency and to allow the strong Rho-independent function of LMO7. Mechanistically, we show that LMO7 colocalizes with F-actin and reduces the G-actin/F-actin ratio via a Rho-independent mechanism. The knockdown of LMO7 in HeLa and MDA-MB-231 cells compromises both basal and Rho-stimulated MRTF activities and impairs the migration of MDA-MB-231 breast cancer cells. We also show that LMO7 is upregulated in the stroma of invasive breast carcinoma in a manner that correlates with the increased expression of SRF target genes that regulate muscle and actin cytoskeleton functions. Together, this study reveals a novel cell-specific mechanism regulating Rho-MRTF-SRF signaling and breast cancer cell migration and identifies a role for actin-RPEL interactions in integrating Rho and cell-specific signals to achieve both the synergistic and Rho-dependent activation of MRTFs. PMID:21670154

  2. Quercetin, kaempferol, myricetin, and fatty acid content among several Hibiscus sabdariffa accession calyces based on maturity in a greenhouse

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Flavonols including quercetin, kaempferol, myricetin, and fatty acids in plants have many useful health attributes including antioxidants, cholesterol lowering, and cancer prevention. Six accessions of roselle, Hibiscus sabdariffa calyces were evaluated for quercetin, kaempferol, and myricetin conte...

  3. Rapid dimerization of quercetin through an oxidative mechanism in the presence of serum albumin decreases its ability to induce cytotoxicity in MDA-MB-231 cells.

    PubMed

    Pham, Anh; Bortolazzo, Anthony; White, J Brandon

    2012-10-19

    Quercetin is a member of the flavonoid family and has been previously shown to have a variety of anti-cancer activities. We and others have reported anti-proliferation, cell cycle arrest, and induction of apoptosis of cancer cells after treatment with quercetin. Quercetin has also been shown to undergo oxidation. However, it is unclear if quercetin or one of its oxidized forms is responsible for cell death. Here we report that quercetin rapidly oxidized in cell culture media to form a dimer. The quercetin dimer is identical to a dimer that is naturally produced by onions. The quercetin dimer and quercetin-3-O-glucopyranoside are unable to cross the cell membrane and do not kill MDA-MB-231 cells. Finally, supplementing the media with ascorbic acid increases quercetin's ability to induce cell death probably by reduction oxidative dimerization. Our results suggest that an unmodified quercetin is the compound that elicits cell death. PMID:23000408

  4. Rapid dimerization of quercetin through an oxidative mechanism in the presence of serum albumin decreases its ability to induce cytotoxicity in MDA-MB-231 cells

    SciTech Connect

    Pham, Anh; Bortolazzo, Anthony; White, J. Brandon

    2012-10-19

    Highlights: Black-Right-Pointing-Pointer Quercetin cannot be detected intracellularly despite killing MDA-MB-231 cells. Black-Right-Pointing-Pointer Quercetin forms a heterodimer through oxidation in media with serum. Black-Right-Pointing-Pointer The quercetin heterodimer does not kill MDA-MB-231 cells. Black-Right-Pointing-Pointer Ascorbic acid stabilizes quercetin increasing cell death in quercetin treated cells. Black-Right-Pointing-Pointer Quercetin, and not a modified form, is responsible for apoptosis and cell death. -- Abstract: Quercetin is a member of the flavonoid family and has been previously shown to have a variety of anti-cancer activities. We and others have reported anti-proliferation, cell cycle arrest, and induction of apoptosis of cancer cells after treatment with quercetin. Quercetin has also been shown to undergo oxidation. However, it is unclear if quercetin or one of its oxidized forms is responsible for cell death. Here we report that quercetin rapidly oxidized in cell culture media to form a dimer. The quercetin dimer is identical to a dimer that is naturally produced by onions. The quercetin dimer and quercetin-3-O-glucopyranoside are unable to cross the cell membrane and do not kill MDA-MB-231 cells. Finally, supplementing the media with ascorbic acid increases quercetin's ability to induce cell death probably by reduction oxidative dimerization. Our results suggest that an unmodified quercetin is the compound that elicits cell death.

  5. Development and characterization of self-assembling lecithin-based mixed polymeric micelles containing quercetin in cancer treatment and an in vivo pharmacokinetic study.

    PubMed

    Chen, Ling-Chun; Chen, Ying-Chen; Su, Chia-Yu; Hong, Chung-Shu; Ho, Hsiu-O; Sheu, Ming-Thau

    2016-01-01

    Quercetin (Que) is known to have biological benefits including an anticancer effect, but low water solubility limits its clinical application. The aim of this study was to develop a lecithin-based mixed polymeric micelle (LMPM) delivery system to improve the solubility and bioavailability of Que. The optimal Que-LMPM, composed of Que, lecithin, Pluronic(®) P123, and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-methoxy[poly(ethylene glycol)-2000] in a proportion of 3:1:17.5:2.5 (w/w), was prepared by a thin-film method. The average size, polydispersion index, encapsulating efficiency, and drug loading of Que-LMPM were 61.60 ± 5.02 nm, 0.589 ± 0.198, 96.87% ± 9.04%, and 12.18% ± 1.11%, respectively. The solubility of Que in the Que-LMPM system increased to 5.81 mg/mL, compared to that of free Que in water of 0.17-7.7 μg/mL. The Que-LMPM system presented a sustained-release property in vitro. The in vitro cytotoxicity assay showed that the 50% inhibitory concentration values toward MCF-7 breast cancer cells for free Que, blank LMPMs, and Que-LMPMs were >200, >200, and 110 μM, respectively, indicating the nontoxicity of the LMPM carrier, but the LMPM formulation enhanced the cytotoxicity of Que against MCF-7 cells. A cellular uptake assay also confirmed the intake of Que-LMPM by MCF-7 cells. An in vivo pharmacokinetic study demonstrated that Que-LMPMs had higher area under the concentration-time curve and a longer half-life, leading to better bioavailability compared to a free Que injection. Due to their nanosize, core-shell structure, and solubilization potential, LMPMs were successfully developed as a drug delivery system for Que to improve its solubility and bioavailability. PMID:27143878

  6. Synergistic Effect of Functionalized Nickel Nanoparticles and Quercetin on Inhibition of the SMMC-7721 Cells Proliferation

    NASA Astrophysics Data System (ADS)

    Guo, Dadong; Wu, Chunhui; Li, Jingyuan; Guo, Airong; Li, Qingning; Jiang, Hui; Chen, Baoan; Wang, Xuemei

    2009-12-01

    The effect of functionalized nickel (Ni) nanoparticles capped with positively charged tetraheptylammonium on cellular uptake of drug quercetin into hepatocellular carcinoma cells (SMMC-7721) has been explored in this study via microscopy and electrochemical characterization as well as MTT assay. Meanwhile, the influence of Ni nanoparticles and/or quercetin on cell proliferation has been further evaluated by the real-time cell electronic sensing (RT-CES) study. Our observations indicate that Ni nanoparticles could efficiently improve the permeability of cancer cell membrane, and remarkably enhance the accumulation of quercetin in SMMC-7721 cells, suggesting that Ni nanoparticles and quercetin would facilitate the synergistic effect on inhibiting proliferation of cancer cells.

  7. Effect of quercetin on apoptosis of PANC-1 cells

    PubMed Central

    Lee, Joo Hyun; Lee, Han-Beom; Jung, Gum O; Oh, Jung Taek; Park, Dong Eun

    2013-01-01

    Purpose To investigate the chemotherapeutic effect of quercetin against cancer cells, signaling pathway of apoptosis was explored in human pancreatic cells. Methods Various anticancer drugs including adriamycin, cisplatin, 5-fluorouracil (5-FU) and gemcitabine were used. Cell viability was measured by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphe-nyltetra zolium bromide assay. Apoptosis was determined by 4'-6-diamidino-2-phenylindole nuclei staining and flow cytometry in PANC-1 cells treated with 50 µg/mL quercetin for 24 hours. Expression of endoplas mic reticulum (ER) stress mediators including, Grp78/Bip, p-PERK, PERK, ATF4, ATF6 and GADD153/CHOP proteins were measured by Western blot analysis. Mitochondrial membrane potential was measured by fluorescence staining with JC-1, rhodamine 123. Quercetin induced the apoptosis of PANC-1, which was characterized as nucleic acid and genomic DNA fragmentation, chromatin condensation, and sub-G0/G1 fraction of cell cycle increase. But not adriamycin, cisplatin, gemcitabine, and 5-FU. PANC-1 cells were markedly sensitive to quercetin. Results Treatment with quercetin resulted in the increased accumulation of intracellular Ca2+ ion. Treatment with quercetin also increased the expression of Grp78/Bip and GADD153/CHOP protein and induced mitochondrial dysfunction. Quercetin exerted cytotoxicity against human pancreatic cancer cells via ER stress-mediated apoptotic signaling including reactive oxygen species production and mitochondrial dysfunction. Conclusion These data suggest that quercetin may be an important modulator of chemosensitivity of cancer cells against anticancer chemotherapeutic agents. PMID:24368982

  8. Synthesis and Anti-Proliferative Effects of Quercetin Derivatives.

    PubMed

    Al-Jabban, Sami M R; Zhang, Xiaojie; Chen, Guanglin; Mekuria, Ermias Addo; Rakotondraibe, Liva Harinantenaina; Chen, Qiao-Hong

    2015-12-01

    Prostate cancer is the most common diagnosed invasive cancer in American men and is the second leading cause of cancer-related deaths. Although there are several therapies successful in treating early, localized stage prostate cancer, current treatment of advanced metastatic castration-resistant prostate cancer remains ineffective due to inevitable progression of resistance to first-line treatment with docetaxel. The natural product quercetin (3,3',4',5,7-pentahydroxyflavone), a flavonoid compound ubiquitous in dietary plants, possesses evidenced potential in treating advanced metastatic castration-resistant prostate cancer. However, its poor bioavailability and moderate potency hinder its advancement into clinical therapy. In order to engineer quercetin derivatives with improved potency and pharmacokinetic profiles for the treatment of advanced metastatic prostate cancer, we started this study with creating a small library of alkylated derivatives of quercetin for in vitro evaluation. The biological data and chemical reactivity of quercetin and its derivatives reported in literature directed us to design 3,4',7-O-trialkylquercetins as our first batch of targets. Consequently, nine 3,4',7-O-trialkylquercetins, together with four 3,7-O- dialkylquercetins, four 3,3',4',7-tetraalkylquercetins, and one 3,3',4'-O-trialkylquercetin, were prepared by one step O-alkylation of commercially available quercetin mediated by potassium carbonate. Their structures were determined by ID and 2D NMR data, and HRMS. Their anti-proliferative activities towards both androgen-refractory and androgen-sensitive prostate cancer cells were evaluated using WST-1 cell proliferation assay. The acquired structure-activity relationships indicate that 3,7-O-dialkylquercetins rather than 3,4',7-O-trialkylquercetins were much more potent than quercetin towards prostate cancer cells. PMID:26882678

  9. The flavonoid quercetin transiently inhibits the activity of taxol and nocodazole through interference with the cell cycle

    PubMed Central

    Samuel, Temesgen; Fadlalla, Khalda; Turner, Timothy; Yehualaeshet, Teshome E.

    2010-01-01

    Quercetin is a flavonoid with anticancer properties. In this study, we examined the effects of quercetin on cell cycle, viability and proliferation of cancer cells, either singly or in combination with the microtubule-targeting drugs taxol and nocodazole. Although quercetin induced cell death in a dose dependent manner, 12.5-50μM quercetin inhibited the activity of both taxol and nocodazole to induce G2/M arrest in various cell lines. Quercetin also partially restored drug-induced loss in viability of treated cells for up to 72 hours. This antagonism of microtubule-targeting drugs was accompanied by a delay in cell cycle progression and inhibition of the buildup of cyclin-B1 at the microtubule organizing center of treated cells. However, quercetin did not inhibit the microtubule targeting of taxol or nocodazole. Despite the short-term protection of cells by quercetin, colony formation and clonogenicity of HCT116 cells were still suppressed by quercetin or quercetin-taxol combination. The status of cell adherence to growth matrix was critical in determining the sensitivity of HCT116 cells to quercetin. We conclude that while long-term exposure of cancer cells to quercetin may prevent cell proliferation and survival, the interference of quercetin with cell cycle progression diminishes the efficacy of microtubule-targeting drugs to arrest cells at G2/M. PMID:21058190

  10. Site-specific anticancer effects of dietary flavonoid quercetin.

    PubMed

    Sak, Katrin

    2014-01-01

    Food-derived flavonoid quercetin, widely distributed in onions, apples, and tea, is able to inhibit growth of various cancer cells indicating that this compound can be considered as a good candidate for anticancer therapy. Although the exact mechanism of this action is not thoroughly understood, behaving as antioxidant and/or prooxidant as well as modulating different intracellular signalling cascades may all play a certain role. Such inhibitory activity of quercetin has been shown to depend first of all on cell lines and cancer types; however, no comprehensive site-specific analysis of this effect has been published. In this review article, cytotoxicity constants of quercetin measured in various human malignant cell lines of different origin were compiled from literature and a clear cancer selective action was demonstrated. The most sensitive malignant sites for quercetin revealed to be cancers of blood, brain, lung, uterine, and salivary gland as well as melanoma whereas cytotoxic activity was higher in more aggressive cells compared to the slowly growing cells showing that the most harmful cells for the organism are probably targeted. More research is needed to overcome the issues of poor water solubility and relatively low bioavailability of quercetin as the major obstacles limiting its clinical use. PMID:24377461

  11. Development and characterization of self-assembling lecithin-based mixed polymeric micelles containing quercetin in cancer treatment and an in vivo pharmacokinetic study

    PubMed Central

    Chen, Ling-Chun; Chen, Ying-Chen; Su, Chia-Yu; Hong, Chung-Shu; Ho, Hsiu-O; Sheu, Ming-Thau

    2016-01-01

    Quercetin (Que) is known to have biological benefits including an anticancer effect, but low water solubility limits its clinical application. The aim of this study was to develop a lecithin-based mixed polymeric micelle (LMPM) delivery system to improve the solubility and bioavailability of Que. The optimal Que-LMPM, composed of Que, lecithin, Pluronic® P123, and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-methoxy[poly(ethylene glycol)-2000] in a proportion of 3:1:17.5:2.5 (w/w), was prepared by a thin-film method. The average size, polydispersion index, encapsulating efficiency, and drug loading of Que-LMPM were 61.60±5.02 nm, 0.589±0.198, 96.87%±9.04%, and 12.18%±1.11%, respectively. The solubility of Que in the Que-LMPM system increased to 5.81 mg/mL, compared to that of free Que in water of 0.17–7.7 μg/mL. The Que-LMPM system presented a sustained-release property in vitro. The in vitro cytotoxicity assay showed that the 50% inhibitory concentration values toward MCF-7 breast cancer cells for free Que, blank LMPMs, and Que-LMPMs were >200, >200, and 110 μM, respectively, indicating the nontoxicity of the LMPM carrier, but the LMPM formulation enhanced the cytotoxicity of Que against MCF-7 cells. A cellular uptake assay also confirmed the intake of Que-LMPM by MCF-7 cells. An in vivo pharmacokinetic study demonstrated that Que-LMPMs had higher area under the concentration–time curve and a longer half-life, leading to better bioavailability compared to a free Que injection. Due to their nanosize, core–shell structure, and solubilization potential, LMPMs were successfully developed as a drug delivery system for Que to improve its solubility and bioavailability. PMID:27143878

  12. IRF-1 inhibits NF-κB activity, suppresses TRAF2 and cIAP1 and induces breast cancer cell specific growth inhibition

    PubMed Central

    Armstrong, Michaele J; Stang, Michael T; Liu, Ye; Yan, Jin; Pizzoferrato, Eva; Yim, John H

    2015-01-01

    Interferon Regulatory Factor (IRF)-1, originally identified as a transcription factor of the human interferon (IFN)-β gene, mediates tumor suppression and may inhibit oncogenesis. We have shown that IRF-1 in human breast cancer cells results in the down-regulation of survivin, tumor cell death, and the inhibition of tumor growth in vivo in xenogeneic mouse models. In this current report, we initiate studies comparing the effect of IRF-1 in human nonmalignant breast cell and breast cancer cell lines. While IRF-1 in breast cancer cells results in growth inhibition and cell death, profound growth inhibition and cell death are not observed in nonmalignant human breast cells. We show that TNF-α or IFN-γ induces IRF-1 in breast cancer cells and results in enhanced cell death. Abrogation of IRF-1 diminishes TNF-α and IFN-γ-induced apoptosis. We test the hypothesis that IRF-1 augments TNF-α-induced apoptosis in breast cancer cells. Potential signaling networks elicited by IRF-1 are investigated by evaluating the NF-κB pathway. TNF-α and/or IFN-γ results in decreased presence of NF-κB p65 in the nucleus of breast cancer cells. While TNF-α and/or IFN-γ can induce IRF-1 in nonmalignant breast cells, a marked change in NF-κB p65 is not observed. Moreover, the ectopic expression of IRF-1 in breast cancer cells results in caspase-3, -7, -8 cleavage, inhibits NF-κB activity, and suppresses the expression of molecules involved in the NF-κB pathway. These data show that IRF-1 in human breast cancer cells elicits multiple signaling networks including intrinsic and extrinsic cell death and down-regulates molecules involved in the NF-κB pathway. PMID:26011589

  13. IRF-1 inhibits NF-κB activity, suppresses TRAF2 and cIAP1 and induces breast cancer cell specific growth inhibition.

    PubMed

    Armstrong, Michaele J; Stang, Michael T; Liu, Ye; Yan, Jin; Pizzoferrato, Eva; Yim, John H

    2015-01-01

    Interferon Regulatory Factor (IRF)-1, originally identified as a transcription factor of the human interferon (IFN)-β gene, mediates tumor suppression and may inhibit oncogenesis. We have shown that IRF-1 in human breast cancer cells results in the down-regulation of survivin, tumor cell death, and the inhibition of tumor growth in vivo in xenogeneic mouse models. In this current report, we initiate studies comparing the effect of IRF-1 in human nonmalignant breast cell and breast cancer cell lines. While IRF-1 in breast cancer cells results in growth inhibition and cell death, profound growth inhibition and cell death are not observed in nonmalignant human breast cells. We show that TNF-α or IFN-γ induces IRF-1 in breast cancer cells and results in enhanced cell death. Abrogation of IRF-1 diminishes TNF-α and IFN-γ-induced apoptosis. We test the hypothesis that IRF-1 augments TNF-α-induced apoptosis in breast cancer cells. Potential signaling networks elicited by IRF-1 are investigated by evaluating the NF-κB pathway. TNF-α and/or IFN-γ results in decreased presence of NF-κB p65 in the nucleus of breast cancer cells. While TNF-α and/or IFN-γ can induce IRF-1 in nonmalignant breast cells, a marked change in NF-κB p65 is not observed. Moreover, the ectopic expression of IRF-1 in breast cancer cells results in caspase-3, -7, -8 cleavage, inhibits NF-κB activity, and suppresses the expression of molecules involved in the NF-κB pathway. These data show that IRF-1 in human breast cancer cells elicits multiple signaling networks including intrinsic and extrinsic cell death and down-regulates molecules involved in the NF-κB pathway. PMID:26011589

  14. Quercetin, a Natural Flavonoid Interacts with DNA, Arrests Cell Cycle and Causes Tumor Regression by Activating Mitochondrial Pathway of Apoptosis

    PubMed Central

    Srivastava, Shikha; Somasagara, Ranganatha R.; Hegde, Mahesh; Nishana, Mayilaadumveettil; Tadi, Satish Kumar; Srivastava, Mrinal; Choudhary, Bibha; Raghavan, Sathees C.

    2016-01-01

    Naturally occurring compounds are considered as attractive candidates for cancer treatment and prevention. Quercetin and ellagic acid are naturally occurring flavonoids abundantly seen in several fruits and vegetables. In the present study, we evaluate and compare antitumor efficacies of quercetin and ellagic acid in animal models and cancer cell lines in a comprehensive manner. We found that quercetin induced cytotoxicity in leukemic cells in a dose-dependent manner, while ellagic acid showed only limited toxicity. Besides leukemic cells, quercetin also induced cytotoxicity in breast cancer cells, however, its effect on normal cells was limited or none. Further, quercetin caused S phase arrest during cell cycle progression in tested cancer cells. Quercetin induced tumor regression in mice at a concentration 3-fold lower than ellagic acid. Importantly, administration of quercetin lead to ~5 fold increase in the life span in tumor bearing mice compared to that of untreated controls. Further, we found that quercetin interacts with DNA directly, and could be one of the mechanisms for inducing apoptosis in both, cancer cell lines and tumor tissues by activating the intrinsic pathway. Thus, our data suggests that quercetin can be further explored for its potential to be used in cancer therapeutics and combination therapy. PMID:27068577

  15. Tumour-initiating cell-specific miR-1246 and miR-1290 expression converge to promote non-small cell lung cancer progression

    PubMed Central

    Zhang, Wen Cai; Chin, Tan Min; Yang, Henry; Nga, Min En; Lunny, Declan Patrick; Lim, Edwin Kok Hao; Sun, Li Li; Pang, Yin Huei; Leow, Yi Ning; Malusay, Shanneen Rossellini Y; Lim, Priscilla Xin Hui; Lee, Jeravan Zili; Tan, Benedict Jian Wei; Shyh-Chang, Ng; Lim, Elaine Hsuen; Lim, Wan Teck; Tan, Daniel Shao Weng; Tan, Eng Huat; Tai, Bee Choo; Soo, Ross Andrew; Tam, Wai Leong; Lim, Bing

    2016-01-01

    The tumour-initiating cell (TIC) model accounts for phenotypic and functional heterogeneity among tumour cells. MicroRNAs (miRNAs) are regulatory molecules frequently aberrantly expressed in cancers, and may contribute towards tumour heterogeneity and TIC behaviour. More recent efforts have focused on miRNAs as diagnostic or therapeutic targets. Here, we identified the TIC-specific miRNAs, miR-1246 and miR-1290, as crucial drivers for tumour initiation and cancer progression in human non-small cell lung cancer. The loss of either miRNA impacted the tumour-initiating potential of TICs and their ability to metastasize. Longitudinal analyses of serum miR-1246 and miR-1290 levels across time correlate their circulating levels to the clinical response of lung cancer patients who were receiving ongoing anti-neoplastic therapies. Functionally, direct inhibition of either miRNA with locked nucleic acid administered systemically, can arrest the growth of established patient-derived xenograft tumours, thus indicating that these miRNAs are clinically useful as biomarkers for tracking disease progression and as therapeutic targets. PMID:27325363

  16. Tumour-initiating cell-specific miR-1246 and miR-1290 expression converge to promote non-small cell lung cancer progression.

    PubMed

    Zhang, Wen Cai; Chin, Tan Min; Yang, Henry; Nga, Min En; Lunny, Declan Patrick; Lim, Edwin Kok Hao; Sun, Li Li; Pang, Yin Huei; Leow, Yi Ning; Malusay, Shanneen Rossellini Y; Lim, Priscilla Xin Hui; Lee, Jeravan Zili; Tan, Benedict Jian Wei; Shyh-Chang, Ng; Lim, Elaine Hsuen; Lim, Wan Teck; Tan, Daniel Shao Weng; Tan, Eng Huat; Tai, Bee Choo; Soo, Ross Andrew; Tam, Wai Leong; Lim, Bing

    2016-01-01

    The tumour-initiating cell (TIC) model accounts for phenotypic and functional heterogeneity among tumour cells. MicroRNAs (miRNAs) are regulatory molecules frequently aberrantly expressed in cancers, and may contribute towards tumour heterogeneity and TIC behaviour. More recent efforts have focused on miRNAs as diagnostic or therapeutic targets. Here, we identified the TIC-specific miRNAs, miR-1246 and miR-1290, as crucial drivers for tumour initiation and cancer progression in human non-small cell lung cancer. The loss of either miRNA impacted the tumour-initiating potential of TICs and their ability to metastasize. Longitudinal analyses of serum miR-1246 and miR-1290 levels across time correlate their circulating levels to the clinical response of lung cancer patients who were receiving ongoing anti-neoplastic therapies. Functionally, direct inhibition of either miRNA with locked nucleic acid administered systemically, can arrest the growth of established patient-derived xenograft tumours, thus indicating that these miRNAs are clinically useful as biomarkers for tracking disease progression and as therapeutic targets. PMID:27325363

  17. Bifunctional combined Au-Fe(2)O(3) nanoparticles for induction of cancer cell-specific apoptosis and real-time imaging.

    PubMed

    Gao, Wen; Ji, Lifei; Li, Lu; Cui, Guanwei; Xu, Kehua; Li, Ping; Tang, Bo

    2012-05-01

    We demonstrate bifunctional combined Au-Fe(2)O(3) nanoparticles (NPs) for selectively induction of apoptosis in cancer cells and real-time imaging. The as-prepared Au-Fe(2)O(3) NPs combine the merits of both Au and γ-Fe(2)O(3) NPs, maintaining excellent fluorescence quenching property and catalytic activity. Conjugated with α(Ⅴ)β(3) integrin-targeting peptide (RGD) and fluorescein isothiocyanate (FITC)-labeled capsase-3 recognition sequence (DEVD) on the Au surface, the resulting RGD/FITC-DEVD-Au-Fe(2)O(3) NPs bind preferentially to integrin α(Ⅴ)β(3)-rich human liver cancer cells (HepG2), sequentially initiate catalytic formation of hydroxyl radicals (·OH) and enable the real-time monitoring of·OH-induced caspase-3-dependent apoptosis in these cancer cells. Furthermore, the catalytic activity of RGD/FITC-DEVD-Au-Fe(2)O(3) NPs is much higher than that of individual γ-Fe(2)O(3) NPs due to the polarization effect at the Au-Fe(2)O(3) interface. Such bifunctional Au-Fe(2)O(3) NPs exhibit simultaneous targeting, therapeutic and imaging functions and are therefore promising for future therapeutic applications in cancer. PMID:22342711

  18. 2,3,7,8-Tetrachlorodibenzo-p-dioxin induced cell-specific drug transporters with acquired cisplatin resistance in cisplatin sensitive cancer cells.

    PubMed

    Gotovdorj, Tuvshinjargal; Lee, Eunil; Lim, Yongchul; Cha, Eun Jeong; Kwon, Daeho; Hong, Eunyoung; Kim, YunJeong; Oh, Min-Yeong

    2014-09-01

    2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) can induce drug transporter genes such as the ATP-binding cassette G member 2 (ABCG2), which contributes to multidrug resistance. We investigated the effect of TCDD pretreatment on drug transporters induction from cancer cells of various origins. Cell viabilities after treatment of cisplatin were measured to evaluate acquiring cisplatin resistance by TCDD. Acquring cisplatin resistance was found only in cisplatin senstivie cancer cells including gastric SNU601, colon LS180, brain CRT-MG and lymphoma Jurkat cells which showed a significant increase in cell viability after combined treatment with TCDD and cisplatin. High increase of ABCG2 gene expression was found in SNU601 and LS180 cells with a mild increase in the expression of the ABCC3, ABCC5,and SLC29A2 genes in SNU601 cells, and of major vault protein (MVP) in LS180 cells. The AhR inhibitor kaempferol suppressed the upregulation of ABCG2 expression and reversed the TCDD-induced increase in cell viability in LS180 cells. However, in CRT-MG cells, other transporter genes including ABCC1, ABCC5, ABCA3, ABCA2, ABCB4, ABCG1, and SLC29A1 were up-regulated. These findings suggested the acquiring cisplatin resistance by TCDD associated with cancer cell-type-specific induction of drug transporters. PMID:25246735

  19. Micro-PET/CT Monitoring of Herpes Thymidine Kinase Suicide Gene Therapy in a Prostate Cancer Xenograft: The Advantage of a Cell-specific Transcriptional Targeting Approach

    PubMed Central

    Johnson, Mai; Sato, Makoto; Burton, Jeremy; Gambhir, Sanjiv S.; Carey, Michael; Wu, Lily

    2010-01-01

    Cancer gene therapy based on tissue-restricted expression of cytotoxic gene should achieve superior therapeutic index over an unrestricted method. This study compared the therapeutic effects of a highly augmented, prostate-specific gene expression method to a strong constitutive promoter-driven approach. Molecular imaging was coupled to gene therapy to ascertain real-time therapeutic activity. The imaging reporter gene (luciferase) and the cytotoxic gene (herpes simplex thymidine kinase) were delivered by adenoviral vectors injected directly into human prostate tumors grafted in SCID mice. Serial bioluminescence imaging, positron emission tomography, and computed tomography revealed restriction of gene expression to the tumors when prostate-specific vector was employed. In contrast, administration of constitutive active vector resulted in strong signals in the liver. Liver serology, tissue histology, and frail condition of animals confirmed liver toxicity suffered by the constitutive active cohorts, whereas the prostate-targeted group was unaffected. The extent of tumor killing was analyzed by apoptotic staining and human prostate marker (prostate-specific antigen). Overall, the augmented prostate-specific expression system was superior to the constitutive approach in safeguarding against systemic toxicity, while achieving effective tumor killing. Integrating noninvasive imaging into cytotoxic gene therapy will provide a useful strategy to monitor gene expression and therapeutic efficacy in future clinical protocols. PMID:16285908

  20. Quercetin-induced downregulation of phospholipase D1 inhibits proliferation and invasion in U87 glioma cells

    SciTech Connect

    Park, Mi Hee; Min, Do Sik

    2011-09-09

    Highlights: {yields} Quercetin, a bioactive flavonoid, suppresses expression and enzymatic activity of phospholipase D1. {yields} Quercetin abolishes NFkB-induced phospholipase D1 expression via inhibition of NFkB transactivation. {yields} Quercetin-induced suppression of phospholipase D1 inhibits invasion and proliferation of human glioma cells. -- Abstract: Phospholipase D (PLD) has been recognized as a regulator of cell proliferation and tumorigenesis, but little is known about the molecules regulating PLD expression. Thus, the identification of small molecules inhibiting PLD expression would be an important advance in PLD-mediated physiology. Quercetin, a ubiquitous bioactive flavonoid, is known to inhibit proliferation and induce apoptosis in a variety of cancer cells. In the present study, we examined the effect of quercetin on the expression of PLD in U87 glioma cells. Quercetin significantly suppressed the expression of PLD1 at the transcriptional level. Moreover, quercetin abolished the protein expression of PLD1 in a time and dose-dependent manner, as well as inhibited PLD activity. Quercetin suppressed NF{kappa}B-induced PLD1 expression via inhibition of NFkB transactivation. Furthermore, quercetin inhibited activation and invasion of metalloproteinase-2 (MMP-2), a key modulator of glioma cell invasion, induced by phosphatidic acid (PA), a product of PLD activity. Taken together these data demonstrate that quercetin abolishes PLD1 expression and subsequently inhibits invasion and proliferation of glioma cells.

  1. Endocrine disrupting activities of the flavonoid nutraceuticals luteolin and quercetin

    PubMed Central

    Nordeen, Steven K.; Bona, Betty J.; Jones, David N.; Lambert, James R.; Jackson, Twila A.

    2013-01-01

    Dietary plant flavonoids have been proposed to contribute to cancer prevention, neuroprotection, and cardiovascular health through their anti-oxidant, anti-inflammatory, pro-apoptotic, and antiproliferative activities. As a consequence, flavonoid supplements are aggressively marketed by the nutraceutical industry for many purposes, including pediatric applications, despite inadequate understanding of their value and drawbacks. We show that two flavonoids, luteolin and quercetin, are promiscuous endocrine disruptors. These flavonoids display progesterone antagonist activity beneficial in a breast cancer model but deleterious in an endometrial cancer model. Concurrently, luteolin possesses potent estrogen agonist activity while quercetin is considerably less effective. These results highlight the promise and peril of flavonoid nutraceuticals and suggest caution in supplementation beyond levels attained in a healthy, plant-rich diet. PMID:23836117

  2. The flavonoid quercetin modulates the hallmark capabilities of hamster buccal pouch tumors.

    PubMed

    Priyadarsini, Ramamurthi Vidya; Vinothini, Govindarajah; Murugan, Ramalingam Senthil; Manikandan, Palrasu; Nagini, Siddavaram

    2011-01-01

    Epidemiological studies have consistently demonstrated the protective effects of dietary phytochemicals against cancer risk. Quercetin, a ubiquitous dietary flavonoid, has attracted considerable attention owing to its potent antioxidant and antiproliferative activities. The present study was designed to investigate the chemopreventive as well as the therapeutic ability of quercetin to modulate the key hallmark capabilities of 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinomas. We analyzed the expression of markers associated with cell proliferation and survival (PCNA, p21, p53, cyclin D1, GST-P), apoptosis (Fas, Fas-L, Bcl-2 family proteins, cytochrome-C, Apaf-1, caspases, PARP, survivin, cFLIP, API1), invasion (MMPs, TIMP-2, RECK), angiogenesis (PlGF, VEGF, VEGF receptors, HIF-1α), as well as the epigenetic markers (HDAC-1, DNMT1) by immunohistochemical, Western blot, and RT-PCR analyses. Simultaneous administration of quercetin to DMBA-painted hamsters reduced tumor incidence and tumor burden, while posttreatment of quercetin resulted in a significant tumor growth delay. In addition, quercetin administration induced cell cycle arrest and apoptosis and blocked invasion and angiogenesis. We found a positive correlation between the inhibition of HDAC-1 and DNMT1 by quercetin and its anticancer properties. A dietary phytochemical such as quercetin that modulates a plethora of molecules offers promise as an ideal candidate for multitargeted cancer prevention and therapy. PMID:21294050

  3. Quercetin enhances the antitumor activity of trichostatin A through upregulation of p53 protein expression in vitro and in vivo.

    PubMed

    Chan, Shu-Ting; Yang, Nae-Cherng; Huang, Chin-Shiu; Liao, Jiunn-Wang; Yeh, Shu-Lan

    2013-01-01

    This study investigated the effects of quercetin on the anti-tumor effect of trichostatin A (TSA), a novel anticancer drug, in vitro and in vivo and the possible mechanisms of these effects in human lung cancer cells. We first showed that quercetin (5 µM) significantly increased the growth arrest and apoptosis in A549 cells (expressing wild-type p53) induced by 25 ng/mL of (82.5 nM) TSA at 48 h by about 25% and 101%, respectively. However, such enhancing effects of quercetin (5 µM) were not significant in TSA-exposed H1299 cells (a p53 null mutant) or were much lower than in A549 cells. In addition, quercetin significantly increased TSA-induced p53 expression in A549 cells. Transfection of p53 siRNA into A549 cells significantly but not completely diminished the enhancing effects of quercetin on TSA-induced apoptosis. Furthermore, we demonstrated that quercetin enhanced TSA-induced apoptosis through the mitochondrial pathway. Transfection of p53 siRNA abolished such enhancing effects of quercetin. However, quercetin increased the acetylation of histones H3 and H4 induced by TSA in A549 cells, even with p53 siRNA transfection as well as in H1299 cells. In a xenograft mouse model of lung cancer, quercetin enhanced the antitumor effect of TSA. Tumors from mice treated with TSA in combination with quercetin had higher p53 and apoptosis levels than did those from control and TSA-treated mice. These data indicate that regulation of the expression of p53 by quercetin plays an important role in enhancing TSA-induced apoptosis in A549 cells. However, p53-independent mechanisms may also contribute to the enhancing effect of quercetin. PMID:23342112

  4. Reactive Oxygen Species Production and Mitochondrial Dysfunction Contribute to Quercetin Induced Death in Leishmania amazonensis

    PubMed Central

    Fonseca-Silva, Fernanda; Inacio, Job D. F.; Canto-Cavalheiro, Marilene M.; Almeida-Amaral, Elmo Eduardo

    2011-01-01

    Background Leishmaniasis, a parasitic disease caused by protozoa of the genus Leishmania, affects more than 12 million people worldwide. Quercetin has generated considerable interest as a pharmaceutical compound with a wide range of therapeutic activities. One such activity is exhibited against the bloodstream parasite Trypanosoma brucei and amastigotes of Leishmania donovani. However, the mechanism of protozoan action of quercetin has not been studied. Methodology/Principal Findings In the present study, we report here the mechanism for the antileishmanial activity of quercetin against Leishmania amazonensis promastigotes. Quercetin inhibited L. amazonensis promastigote growth in a dose- and time- dependent manner beginning at 48 hours of treatment and with maximum growth inhibition observed at 96 hours. The IC50 for quercetin at 48 hours was 31.4 µM. Quercetin increased ROS generation in a dose-dependent manner after 48 hours of treatment. The antioxidant GSH and NAC each significantly reduced quercetin-induced cell death. In addition, quercetin caused mitochondrial dysfunction due to collapse of mitochondrial membrane potential. Conclusions/Significance The effects of several drugs that interfere directly with mitochondrial physiology in parasites such as Leishmania have been described. The unique mitochondrial features of Leishmania make this organelle an ideal drug target while minimizing toxicity. Quercetin has been described as a pro-oxidant, generating ROS which are responsible for cell death in some cancer cells. Mitochondrial membrane potential loss can be brought about by ROS added directly in vitro or induced by chemical agents. Taken together, our results demonstrate that quercetin eventually exerts its antileishmanial effect on L. amazonensis promastigotes due to the generation of ROS and disrupted parasite mitochondrial function. PMID:21346801

  5. Dietary quercetin exacerbates the development of estrogen-induced breast tumors in female ACI rats

    SciTech Connect

    Singh, Bhupendra; Mense, Sarah M.; Bhat, Nimee K.; Putty, Sandeep; Guthiel, William A.; Remotti, Fabrizio; Bhat, Hari K.

    2010-09-01

    Phytoestrogens are plant compounds that structurally mimic the endogenous estrogen 17{beta}-estradiol (E{sub 2}). Despite intense investigation, the net effect of phytoestrogen exposure on the breast remains unclear. The objective of the current study was to examine the effects of quercetin on E{sub 2}-induced breast cancer in vivo. Female ACI rats were given quercetin (2.5 g/kg food) for 8 months. Animals were monitored weekly for palpable tumors, and at the end of the experiment, rats were euthanized, breast tumor and different tissues excised so that they could be examined for histopathologic changes, estrogen metabolic activity and oxidant stress. Quercetin alone did not induce mammary tumors in female ACI rats. However, in rats implanted with E{sub 2} pellets, co-exposure to quercetin did not protect rats from E{sub 2}-induced breast tumor development with 100% of the animals developing breast tumors within 8 months of treatment. No changes in serum quercetin levels were observed in quercetin and quercetin + E{sub 2}-treated groups at the end of the experiment. Tumor latency was significantly decreased among rats from the quercetin + E{sub 2} group relative to those in the E{sub 2} group. Catechol-O-methyltransferase (COMT) activity was significantly downregulated in quercetin-exposed mammary tissue. Analysis of 8-isoprostane F{sub 2{alpha}} (8-iso-PGF{sub 2{alpha}}) levels as a marker of oxidant stress showed that quercetin did not decrease E{sub 2}-induced oxidant stress. These results indicate that quercetin (2.5 g/kg food) does not confer protection against breast cancer, does not inhibit E{sub 2}-induced oxidant stress and may exacerbate breast carcinogenesis in E{sub 2}-treated ACI rats. Inhibition of COMT activity by quercetin may expose breast cells chronically to E{sub 2} and catechol estrogens. This would permit longer exposure times to the carcinogenic metabolites of E{sub 2} and chronic exposure to oxidant stress as a result of metabolic redox

  6. Antioxidant action and cytotoxicity on HeLa and NIH-3T3 cells of new quercetin derivatives

    PubMed Central

    Veverka, Miroslav; Šturdík, Ernest; Jantová, Soňa

    2013-01-01

    Quercetin is a natural polyphenol with proven health beneficial activities. In this study 15 new quercetin derivatives were prepared with the aim to enhance their bioavailability. Modification of their physicochemical properties could herewith improve the action in cells. The prepared compounds were tested for their antioxidant and cytotoxic activity. The ability to scavenge free radicals as well as ferric reducing antioxidant power of the new derivatives was not better than that of unmodified quercetin. But for acetylated esters a better cytotoxic activity was found on human cervical cancer cells HeLa than for the initial molecule. The best effect revealed chloronaphtoquinone quercetin (IC50=13.2 µM). For this compound comparable cytotoxic action on non-cancer murine fibroblast cells was detected (IC50=16.5 µM). The obtained results indicate that appropriate lipophilization of the quercetin molecule could improve its cytotoxic action in cells, probably due to its enhanced bioavailability. PMID:24678260

  7. Quercetin mediated reduction of angiogenic markers and chaperones in DLA-induced solid tumours.

    PubMed

    Anand, Kushi; Asthana, Pallavi; Kumar, Anup; Ambasta, Rashmi K; Kumar, Pravir

    2011-01-01

    Diet-derived flavonoids, in particular quercetin, may play advantageous roles by preventing or/and inhibiting oncogenesis. Evidence suggests that quercetin can elicit various properties depending on the cell type. The aim of this study was to evaluate its effects on Dalton's lymphoma ascites (DLA) induced solid tumours and to identify the target(s) of action. We addressed this question by inducing subcutaneous solid tumours in Swiss albino mice and investigated whether the quercetin affects essential biological processes that are responsible for tumour growth, morphology, angiogenesis and apoptosis. We also studied influence on several heat shock proteins (HSPs). Our findings demonstrate that intra-tumour administration of quercetin results in decreased volume/weight. Furthermore, we demonstrate that quercetin promotes apoptosis of cancer cells by down-regulating the levels of Hsp90 and Hsp70. Depletion of these two chaperones by quercetin might result in triggering of caspase-3 in treated tumours. Moreover, it also down-regulated the expression of major key angiogenic or pro-angiogenic factors, like HIF-1α and VEGF In addition, H and E staining together with immunofluorescence of fixed tumour tissue provided evidence in support of increased cell death in quercetin-treated mice. PMID:22393949

  8. Quercetin suppresses cellular migration and invasion in human head and neck squamous cell carcinoma (HNSCC).

    PubMed

    Chan, Chien-Yi; Lien, Chia-Hsien; Lee, Ming-Fen; Huang, Chun-Yin

    2016-06-01

    Head and neck squamous cell carcinoma (HNSCC) with aberrant epidermal growth factor receptor (EGFR) signaling is often associated with a poor prognosis and a low survival rate. Hence, efficient inhibition of the EGFR signaling-mediated malignancy would improve survival rate. In a previous study, we demonstrated that quercetin appears to be a potent anti-tumorigenic agent through its inhibition of the EGFR/Akt pathway in oral cancer, but its anti-metastatic potential in HNSCC remains unclear [1]. Here, we have hypothesized that quercetin might be effective in metastatic inhibition in EGFR-overexpressing HNSCC cells. Quercetin treatment with 10 μM (half concentration of IC50) suppressed cell migration and invasion in EGFR-overexpressing HSC-3 and FaDu HNSCC cells. Quercetin also inhibited the colony growth of HSC-3 cells embedded in a Matrigel matrix. Among matrix metalloproteinases (MMPs), the secreted gelatinases MMP-2 and MMP-9 are responsible for the degradation of gelatin in the extracellular matrix and type IV collagen in the basement membrane; and this degradation event is crucial for the migration from the origin and the invasion into the bone in HNSCC. Quercetin (10 μM) treatment also suppressed the expression and proteolytic activity of MMP-2 and MMP-9. Taken together, our data indicate that quercetin is an effective anti-cancer agent against MMP-2- and MMP-9-mediated metastasis in EGFR-overexpressing HNSCC. PMID:27510965

  9. Suppression of HSP27 increases the anti-tumor effects of quercetin in human leukemia U937 cells

    PubMed Central

    CHEN, XI; DONG, XIU-SHUAI; GAO, HAI-YAN; JIANG, YONG-FANG; JIN, YING-LAN; CHANG, YU-YING; CHEN, LI-YAN; WANG, JING-HUA

    2016-01-01

    Quercetin, a natural flavonoid, inhibits the growth of leukemia cells and induces apoptosis. Heat shock protein 27 (HSP27) has been reported to promote the development of leukemia by protecting tumor cells from apoptosis through various mechanisms. The present study investigated the effects of small hairpin (sh)RNA-mediated HSP27 knockdown on the anti-cancer effects of quercetin in U937 human leukemia cells. Cells were transfected with recombinant lentiviral vector pCMV-G-NR-U6-shHSP27 (shHSP27), which expressed shRNA specifically targeting the HSP27 gene, alone or in combination with quercetin. The results showed that shHSP27 and quercetin synergistically inhibited U937 cell proliferation and induced apoptosis by decreasing the Bcl2-to-Bax ratio. Furthermore, this combined treatment significantly suppressed the infiltration of tumor cells and the expression of angiogenesis-associated proteins HIF1α and VEGF. Compared with shHSP27 or quercetin alone, shHSP27 plus quercetin markedly decreased the protein expression of cyclinD1 and thus blocked the cell cycle at G1 phase. The Notch/AKT/mTOR signaling pathway is important in tumor aggressiveness; quercetin plus shHSP27 significantly decreased Notch 1 expression and the phosphorylation levels of the downstream signaling proteins AKT and mTOR. The inhibitory effects of quercetin plus shHSP27 on this pathway may thus have been responsible for the cell cycle arrest, inhibition of proliferations and infiltration as well as enhancement of apoptosis. Therefore, these findings collectively suggested that suppression of HSP27 expression amplified the anti-cancer effects of quercetin in U937 human leukemia cells, and that quercetin in combination with shHSP27 represents a promising therapeutic strategy for human leukemia. PMID:26648539

  10. Effect of different exposed lights on quercetin and quercetin glucoside content in onion (Allium cepa L.)

    PubMed Central

    Ko, Eun Young; Nile, Shivraj Hariram; Sharma, Kavita; Li, Guan Hao; Park, Se Won

    2014-01-01

    Quercetin and quercetin glucosides are the major flavonols present in onion (Allium cepa L.) and are predominantly present as quercetin, quercetin-3,4′-diglucoside and quercetin-4′-glucoside. Effect of different light wavelengths on onion after harvest and storage, with fluorescent, blue, red and ultra violet light influenced the quercetin and quercetin glucosides profile. In a peeled onion, all the light treatments elevated quercetin content in bulb. Among them, particularly fluorescent light effect was more eminent which stimulates the maximum synthesis of quercetin in onion. In case of whole onion bulb, skin and pulp showed different responses to light treatment, respectively. The pulp had the highest quercetin glucosides under blue light, whereas the lowest under fluorescent light. Onion skin showed nearly opposite pattern as compared to the pulp. In particular, light treatment proved to be a better way to increase the level of quercetin content in onions which might be utilized for industrial production of bioactive compounds from onion and onion waste products. PMID:26150744

  11. Effect of different exposed lights on quercetin and quercetin glucoside content in onion (Allium cepa L.).

    PubMed

    Ko, Eun Young; Nile, Shivraj Hariram; Sharma, Kavita; Li, Guan Hao; Park, Se Won

    2015-07-01

    Quercetin and quercetin glucosides are the major flavonols present in onion (Allium cepa L.) and are predominantly present as quercetin, quercetin-3,4'-diglucoside and quercetin-4'-glucoside. Effect of different light wavelengths on onion after harvest and storage, with fluorescent, blue, red and ultra violet light influenced the quercetin and quercetin glucosides profile. In a peeled onion, all the light treatments elevated quercetin content in bulb. Among them, particularly fluorescent light effect was more eminent which stimulates the maximum synthesis of quercetin in onion. In case of whole onion bulb, skin and pulp showed different responses to light treatment, respectively. The pulp had the highest quercetin glucosides under blue light, whereas the lowest under fluorescent light. Onion skin showed nearly opposite pattern as compared to the pulp. In particular, light treatment proved to be a better way to increase the level of quercetin content in onions which might be utilized for industrial production of bioactive compounds from onion and onion waste products. PMID:26150744

  12. Quercetin interaction with the chloroplast ATPase complex.

    PubMed

    Shoshan, V; Shahak, Y; Shavit, N

    1980-07-01

    1. Quercetin, a flavonoid which acts as an energy transfer inhibitor in photophosphorylation is shown to inhibit the P-ATP exchange activity of membrane-bound CF1 and the ATPase activity of isolated CF1. Quercetin, affects also the proton uptake in chloroplasts in a manner similar to that of dicyclohexylcarbodiimide. 2. The light-dependent proton uptake in EDTA-treated chloroplasts is stimulated by quercetin. In untreated chloroplasts quercetin has a dual effect: it enhances at pH above 7.5 while at lower pH values it decreases the extent of H+ uptake. Similar effects were obtained with dicyclohexylcarbodiimide. 3. Like quercetin, dicyclohexylcarbodiimide was also found to inhibit the ATPase activity of isolated CF1. 4. Quercetin inhibits uncoupled electron transport induced by either EDTA-treatment of chloroplasts or by addition of uncouplers. Quercetin restores H+ uptake in both types of uncoupled chloroplasts. 5. The mode of action of quercetin and dicyclohexylcarbodiimide in photophosphorylation is discussed, and interaction with both CF1 and F0 is suggested. PMID:6446936

  13. Multifaceted preventive effects of single agent quercetin on a human prostate adenocarcinoma cell line (PC-3): implications for nutritional transcriptomics and multi-target therapy.

    PubMed

    Noori-Daloii, Mohammad R; Momeny, Majid; Yousefi, Mehdi; Shirazi, Forough Golsaz; Yaseri, Mehdi; Motamed, Nasrin; Kazemialiakbar, Nazanin; Hashemi, Saeed

    2011-12-01

    The aim of the present study is to evaluate the effects of quercetin, a dietary flavonoid, on human prostate adenocarcinoma PC-3 cells. Lactate dehydrogenase (LDH) release, microculture tetrazolium test (MTT assay) and real-time PCR array were employed to evaluate the effects of quercetin on cell cytotoxicity, cell proliferation and expression of various genes in PC-3 cell line. Quercetin inhibited cell proliferation and modulated the expression of genes involved in DNA repair, matrix degradation and tumor invasion, angiogenesis, apoptosis, cell cycle, metabolism and glycolysis. No cytotoxicity of quercetin on PC-3 cells was observed. Taken together, as shown by the issues of the current study, the manifold inhibitory effects of quercetin on PC-3 cells may introduce quercetin as an efficacious anticancer agent in order to be used in the future nutritional transcriptomic investigations and multi-target therapy to overcome the therapeutic impediments against prostate cancer. PMID:20596804

  14. Anxiety and cognitive effects of quercetin liposomes in rats.

    PubMed

    Priprem, Aroonsri; Watanatorn, Jintanaporn; Sutthiparinyanont, Saengrawee; Phachonpai, Wathita; Muchimapura, Supaporn

    2008-03-01

    Quercetin, an effective flavonol used as an antioxidant, was investigated for its anxiolytic and cognitive activities in male Wistar rats. Oral quercetin (300 mg/kg body weight/day) was compared with oral and intranasal quercetin liposomes (20 microg/day). Quercetin liposomes, in a mixture of egg phosphatidylcholine, cholesterol, and quercetin (2:1:1) and dispersed in 50% polyethylene glycol in water, were approximately 200 nm in mean particle diameter and negative surface charge with a range of encapsulation efficiency of 60% to 80%. Anxiolytic and cognitive-enhancing effects of quercetin, conventional and liposomal, were subjected to elevated plus maze and Morris water maze tests, respectively. Both conventional and quercetin liposomes showed anxiolytic and cognitive-enhancing effects. A lower dose and a faster rate were observed with intranasal quercetin liposomes when compared with oral quercetin, conventional and liposomal. The intranasal quercetin liposomes are effective in the delivery of quercetin to the central nervous system. PMID:18249157

  15. Quercetin and the mitochondria: A mechanistic view.

    PubMed

    de Oliveira, Marcos Roberto; Nabavi, Seyed Mohammad; Braidy, Nady; Setzer, William N; Ahmed, Touqeer; Nabavi, Seyed Fazel

    2016-01-01

    Quercetin is an important flavonoid that is ubiquitously present in the diet in a variety of fruits and vegetables. It has been traditionally viewed as a potent antioxidant and anti-inflammatory molecule. However, recent studies have suggested that quercetin may exert its beneficial effects independent of its free radical-scavenging properties. Attention has been placed on the effect of quercetin on an array of mitochondrial processes. Quercetin is now recognized as a phytochemical that can modulate pathways associated with mitochondrial biogenesis, mitochondrial membrane potential, oxidative respiration and ATP anabolism, intra-mitochondrial redox status, and subsequently, mitochondria-induced apoptosis. The present review evaluates recent evidence on the ability of quercetin to interact with the abovementioned pathways, and critically analyses how, such interactions can exert protection against mitochondrial damage in response to toxicity induced by several exogenously and endogenously-produced cellular stressors, and oxidative stress in particular. PMID:26740171

  16. The impact of quercetin on cisplatin-induced clastogenesis and apoptosis in murine marrow cells.

    PubMed

    Attia, Sabry M

    2010-05-01

    The aim of the present investigation is to determine whether the quercetin in combination with cisplatin can ameliorate cisplatin-induced clastogenesis and apoptosis in the bone marrow cells of mice. The scoring of chromosomal aberrations, micronuclei and mitotic activity were undertaken in the current study as markers of clastogenicity. Apoptosis was analysed by the Annexin V-propidium iodide assay and the occurrence of a hypodiploid DNA peak. Oxidative stress markers such as bone marrow lipid peroxidation and reduced glutathione were assessed as a possible mechanism underlying this amelioration. Quercetin was neither clastogenic nor apoptogenic in mice at doses equivalent to 50 or 100 mg/kg for 2 days. Pre-treatment of mice with quercetin significantly reduced cisplatin-induced clastogenesis and apoptosis in the bone marrow cells and these effects were dose and time dependent. Prior administration of quercetin ahead of cisplatin challenge ameliorated oxidative stress markers. Overall, this study provides for the first time that quercetin has a protective role in the abatement of cisplatin-induced clastogenesis and apoptosis in the bone marrow cells of mice that resides, at least in part, in its antioxidant effects. Therefore, quercetin can be a good candidate to decrease the deleterious effects of cisplatin in the bone marrow cells of cancer patients treated with this drug. PMID:20156843

  17. Differential Effects of Quercetin and Quercetin Glycosides on Human α7 Nicotinic Acetylcholine Receptor-Mediated Ion Currents.

    PubMed

    Lee, Byung-Hwan; Choi, Sun-Hye; Kim, Hyeon-Joong; Jung, Seok-Won; Hwang, Sung-Hee; Pyo, Mi-Kyung; Rhim, Hyewhon; Kim, Hyoung-Chun; Kim, Ho-Kyoung; Lee, Sang-Mok; Nah, Seung-Yeol

    2016-07-01

    Quercetin is a flavonoid usually found in fruits and vegetables. Aside from its antioxidative effects, quercetin, like other flavonoids, has a various neuropharmacological actions. Quercetin-3-O-rhamnoside (Rham1), quercetin-3-O-rutinoside (Rutin), and quercetin- 3-(2(G)-rhamnosylrutinoside (Rham2) are mono-, di-, and tri-glycosylated forms of quercetin, respectively. In a previous study, we showed that quercetin can enhance α7 nicotinic acetylcholine receptor (α7 nAChR)-mediated ion currents. However, the role of the carbohydrates attached to quercetin in the regulation of α7 nAChR channel activity has not been determined. In the present study, we investigated the effects of quercetin glycosides on the acetylcholine induced peak inward current (IACh) in Xenopus oocytes expressing the α7 nAChR. IACh was measured with a two-electrode voltage clamp technique. In oocytes injected with α7 nAChR copy RNA, quercetin enhanced IACh, whereas quercetin glycosides inhibited IACh. Quercetin glycosides mediated an inhibition of IACh, which increased when they were pre-applied and the inhibitory effects were concentration dependent. The order of IACh inhibition by quercetin glycosides was Rutin≥Rham1>Rham2. Quercetin glycosides-mediated IACh enhancement was not affected by ACh concentration and appeared voltage-independent. Furthermore, quercetin-mediated IACh inhibition can be attenuated when quercetin is co-applied with Rham1 and Rutin, indicating that quercetin glycosides could interfere with quercetin-mediated α7 nAChR regulation and that the number of carbohydrates in the quercetin glycoside plays a key role in the interruption of quercetin action. These results show that quercetin and quercetin glycosides regulate the α7 nAChR in a differential manner. PMID:27098860

  18. Differential Effects of Quercetin and Quercetin Glycosides on Human α7 Nicotinic Acetylcholine Receptor-Mediated Ion Currents

    PubMed Central

    Lee, Byung-Hwan; Choi, Sun-Hye; Kim, Hyeon-Joong; Jung, Seok-Won; Hwang, Sung-Hee; Pyo, Mi-Kyung; Rhim, Hyewhon; Kim, Hyoung-Chun; Kim, Ho-Kyoung; Lee, Sang-Mok; Nah, Seung-Yeol

    2016-01-01

    Quercetin is a flavonoid usually found in fruits and vegetables. Aside from its antioxidative effects, quercetin, like other flavonoids, has a various neuropharmacological actions. Quercetin-3-O-rhamnoside (Rham1), quercetin-3-O-rutinoside (Rutin), and quercetin-3-(2(G)-rhamnosylrutinoside (Rham2) are mono-, di-, and tri-glycosylated forms of quercetin, respectively. In a previous study, we showed that quercetin can enhance α7 nicotinic acetylcholine receptor (α7 nAChR)-mediated ion currents. However, the role of the carbohydrates attached to quercetin in the regulation of α7 nAChR channel activity has not been determined. In the present study, we investigated the effects of quercetin glycosides on the acetylcholine induced peak inward current (IACh) in Xenopus oocytes expressing the α7 nAChR. IACh was measured with a two-electrode voltage clamp technique. In oocytes injected with α7 nAChR copy RNA, quercetin enhanced IACh, whereas quercetin glycosides inhibited IACh. Quercetin glycosides mediated an inhibition of IACh, which increased when they were pre-applied and the inhibitory effects were concentration dependent. The order of IACh inhibition by quercetin glycosides was Rutin≥Rham1>Rham2. Quercetin glycosides-mediated IACh enhancement was not affected by ACh concentration and appeared voltage-independent. Furthermore, quercetin-mediated IACh inhibition can be attenuated when quercetin is co-applied with Rham1 and Rutin, indicating that quercetin glycosides could interfere with quercetin-mediated α7 nAChR regulation and that the number of carbohydrates in the quercetin glycoside plays a key role in the interruption of quercetin action. These results show that quercetin and quercetin glycosides regulate the α7 nAChR in a differential manner. PMID:27098860

  19. Quercetin in brain diseases: Potential and limits.

    PubMed

    Dajas, Federico; Abin-Carriquiry, Juan Andrés; Arredondo, Florencia; Blasina, Fernanda; Echeverry, Carolina; Martínez, Marcela; Rivera, Felicia; Vaamonde, Lucía

    2015-10-01

    Quercetin is a ubiquitous flavonoid present in beverages, food and plants that has been demonstrated to have a role in the prevention of neurodegenerative and cerebrovascular diseases. In neuronal culture, quercetin increases survival against oxidative insults. Antioxidation appears to be a necessary but not sufficient condition for its neuroprotective action and modulation of intracellular signaling and transcription factors, increasing the expression of antioxidant and pro survival proteins and modulating inflammation, appears as important for neuronal protection. Quercetin also regulates the activity of kinases, changing the phosphorylation state of target molecules, resulting in modulation of cellular function and gene expression. Concentrations of quercetin higher than 100 μM consistently show cytotoxic and apoptotic effects by its autoxidation and generation of toxic quinones. In vivo, results are controversial with some studies showing neuroprotection by quercetin and others not, requiring a drug delivery system or chronic treatments to show neuroprotective effects. The blood and brain bioavailability of free quercetin after ingestion is a complex and controversial process that produces final low concentrations, a fact that has led to suggestions that metabolites would be active by themselves and/or as pro-drugs that would release the active aglycone in the brain. Available studies show that in normal or low oxidative conditions, chronic treatments with quercetin contributes to re-establish the redox regulation of proteins, transcription factors and survival signaling cascades that promote survival. In the presence of highly oxidative conditions such as in an ischemic tissue, quercetin could become pro-oxidant and toxic. At present, evidence points to quercetin as a preventive molecule for neuropathology when administered in natural matrices such as vegetables and food. More research is needed to support its use as a lead compound in its free form in

  20. Assessment of anti-cytogenotoxic effects of quercetin in animals treated with topotecan.

    PubMed

    Bakheet, Saleh A

    2011-01-01

    The present investigation was directed to study the possible chemoprotective activity of orally administered quercetin against topotecan-induced cyto- and genotoxicity towards mouse somatic cells in vivo. DNA strand breaks, micronuclei formation, and mitotic activity were undertaken in the current study as markers of cyto- and genotoxicity. Oxidative stress markers such as intracellular reactive oxygen species generation, lipid peroxidation, and reduced and oxidized glutathione were assessed in bone marrow as a possible mechanism underlying this amelioration. Quercetin was neither cytotoxic nor genotoxic in mice at doses tested. Pretreatment of mice with quercetin significantly reduced topotecan-induced genotoxicity and cytotoxicity in bone marrow cells, and these effects were dose dependent. Moreover, prior administration of quercetin ahead of topotecan challenge ameliorated oxidative stress markers. In conclusion, quercetin has a protective role in the abatement of topotecan-induced cyto- and genotoxicity in the bone marrow cells of mice that resides, at least in part, on its antioxidant effects. Based on the data presented, strategies can be developed to decrease the topotecan-induced bone marrow suppression and secondary malignancy in cancer patients and medical personnel exposing to topotecan. PMID:21904648

  1. Quercetin abrogates IL-6/STAT3 signaling and inhibits glioblastoma cell line growth and migration

    SciTech Connect

    Michaud-Levesque, Jonathan; Bousquet-Gagnon, Nathalie; Beliveau, Richard

    2012-05-01

    Evidence has suggested that STAT3 functions as an oncogene in gliomagenesis. As a consequence, changes in the inflammatory microenvironment are thought to promote tumor development. Regardless of its origin, cancer-related inflammation has many tumor-promoting effects, such as the promotion of cell cycle progression, cell proliferation, cell migration and cell survival. Given that IL-6, a major cancer-related inflammatory cytokine, regulates STAT3 activation and is upregulated in glioblastoma, we sought to investigate the inhibitory effects of the chemopreventive flavonoid quercetin on glioblastoma cell proliferation and migration triggered by IL-6, and to determine the underlying mechanisms of action. In this study, we show that quercetin is a potent inhibitor of the IL-6-induced STAT3 signaling pathway in T98G and U87 glioblastoma cells. Exposure to quercetin resulted in the reduction of GP130, JAK1 and STAT3 activation by IL-6, as well as a marked decrease of the proliferative and migratory properties of glioblastoma cells induced by IL-6. Interestingly, quercetin also modulated the expression of two target genes regulated by STAT3, i.e. cyclin D1 and matrix metalloproteinase-2 (MMP-2). Moreover, quercetin reduced the recruitment of STAT3 at the cyclin D1 promoter and inhibited Rb phosphorylation in the presence of IL-6. Overall, these results provide new insight into the role of quercetin as a blocker of the STAT3 activation pathway stimulated by IL-6, with a potential role in the prevention and treatment of glioblastoma.

  2. Primordial Germ Cell Specification and Migration

    PubMed Central

    Marlow, Florence

    2015-01-01

    Primordial germ cells are the progenitor cells that give rise to the gametes. In some animals, the germline is induced by zygotic transcription factors, whereas in others, primordial germ cell specification occurs via inheritance of maternally provided gene products known as germ plasm. Once specified, the primordial germ cells of some animals must acquire motility and migrate to the gonad in order to survive. In all animals examined, perinuclear structures called germ granules form within germ cells. This review focuses on some of the recent studies, conducted by several groups using diverse systems, from invertebrates to vertebrates, which have provided mechanistic insight into the molecular regulation of germ cell specification and migration. PMID:26918157

  3. Differential protein expression of peroxiredoxin I and II by benzo(a)pyrene and quercetin treatment in 22Rv1 and PrEC prostate cell lines

    SciTech Connect

    Chaudhary, Amit; Pechan, Tibor; Willett, Kristine L. . E-mail: kwillett@olemiss.edu

    2007-04-15

    Mechanisms of benzo(a)pyrene (BaP)-mediated toxicity and chemopreventative potential of quercetin in prostate cancer are poorly understood. Two-dimensional gel electrophoresis was used to map the differences in protein expression in BaP (1 {mu}M)- and quercetin (5 {mu}M)-treated 22Rv1 human prostate cancer cells. As compared to DMSO, 26 proteins in BaP and 41 proteins in quercetin were found to be differentially expressed ({+-} 2-fold). Western blots confirmed that BaP increased peroxiredoxin (Prx) Prx I and decreased Prx II in 22Rv1 cells. Similar results were found in PrEC normal prostate epithelial cells. Quercetin (up to 10 {mu}M) upregulated Prx II without altering Prx I levels in 22Rv1 cells whereas in PrEC cells, it did not alter the constitutive protein expression of Prx I or II. The lack of quercetin-mediated changes in Prx expression suggests that quercetin does not interfere with H{sub 2}O{sub 2} levels, and thus may have no deleterious effect in normal prostate cells. Quercetin inhibited both BaP-mediated effects on Prx I and II in 22Rv1 cells. In PrEC cells, quercetin inhibited BaP-mediated upregulation of Prx I and had tendency to neutralize BaP-mediated downregulation of Prx II. Quercetin also inhibited BaP-induced concentrations of reactive oxygen species in both 22Rv1 and PrEC cells. These results suggest that Prx I and II may be involved in BaP-mediated toxicity and the potential chemopreventative mechanisms of quercetin.

  4. Quercetin Directly Interacts with Vitamin D Receptor (VDR): Structural Implication of VDR Activation by Quercetin.

    PubMed

    Lee, Ki-Young; Choi, Hye-Seung; Choi, Ho-Sung; Chung, Ka Young; Lee, Bong-Jin; Maeng, Han-Joo; Seo, Min-Duk

    2016-03-01

    The vitamin D receptor (VDR) is a member of the nuclear receptor (NR) superfamily. The VDR binds to active vitamin D3 metabolites, which stimulates downstream transduction signaling involved in various physiological activities such as calcium homeostasis, bone mineralization, and cell differentiation. Quercetin is a widely distributed flavonoidin nature that is known to enhance transactivation of VDR target genes. However, the detailed molecular mechanism underlying VDR activation by quercetin is not well understood. We firstdemonstrated the interaction between quercetin and the VDR at the molecular level by using fluorecence quenching and saturation transfer difference (STD) NMR experiments. The dissociation constant (Kd) of quercetin and the VDR was 21.15 ± 4.31 μM, and the mapping of quercetin subsites for VDR binding was performed using STD-NMR. The binding mode of quercetin was investigated by a docking study combined with molecular dynamics (MD) simulation. Quercetin might serve as a scaffold for the development of VDR modulators with selective biological activities. PMID:26902087

  5. Quercetin Directly Interacts with Vitamin D Receptor (VDR): Structural Implication of VDR Activation by Quercetin

    PubMed Central

    Lee, Ki-Young; Choi, Hye-Seung; Choi, Ho-Sung; Chung, Ka Young; Lee, Bong-Jin; Maeng, Han-Joo; Seo, Min-Duk

    2016-01-01

    The vitamin D receptor (VDR) is a member of the nuclear receptor (NR) superfamily. The VDR binds to active vitamin D3 metabolites, which stimulates downstream transduction signaling involved in various physiological activities such as calcium homeostasis, bone mineralization, and cell differentiation. Quercetin is a widely distributed flavonoid in nature that is known to enhance transactivation of VDR target genes. However, the detailed molecular mechanism underlying VDR activation by quercetin is not well understood. We first demonstrated the interaction between quercetin and the VDR at the molecular level by using fluorescence quenching and saturation transfer difference (STD) NMR experiments. The dissociation constant (Kd) of quercetin and the VDR was 21.15 ± 4.31 μM, and the mapping of quercetin subsites for VDR binding was performed using STD-NMR. The binding mode of quercetin was investigated by a docking study combined with molecular dynamics (MD) simulation. Quercetin might serve as a scaffold for the development of VDR modulators with selective biological activities. PMID:26902087

  6. The pleiotropic flavonoid quercetin: from its metabolism to the inhibition of protein kinases in chronic lymphocytic leukemia.

    PubMed

    Russo, Gian Luigi; Russo, Maria; Spagnuolo, Carmela

    2014-10-01

    Quercetin is a flavonoid, of the subclass flavonols, possessing potential anticancer properties. It has often been defined as a functionally pleiotropic molecule because it can simultaneously target multiple pathways bypassing or ameliorating the onset of drug resistance in malignant cells. In this context, we reviewed the sometimes paradoxical antioxidant properties of quercetin and the functional role of its glucuronide and/or sulfate conjugates to discuss the low bioavailability of the molecule measured in vivo. We recently demonstrated that quercetin is able to sensitize several leukemia cell lines as well as B cells isolated from patients affected by chronic lymphocytic leukemia (CLL) to death ligand agonists (anti-CD95 and rTRAIL). The flavonol also potentiates the effect of canonical and innovative chemotherapeutic drugs (fludarabine and ABT-737) against CLL. The apoptosis-enhancing activity of quercetin in cell lines and B-CLL cells depends upon the modulated expression and activity of Mcl-1, an anti-apoptotic protein belonging to the Bcl-2 family. Herein, we suggest that the pleotropic activity of quercetin in CLL is obtained by the direct inhibition of key protein kinases, which positively regulate Mcl-1 activity and by indirect downregulation of Mcl-1 mRNA and protein levels acting on its mRNA stability and proteasome-mediated degradation. Finally, we highlighted the pros and cons of quercetin supplementation in cancer therapy and in prevention. PMID:25096193

  7. Cell specific, variable density, polymer microspheres

    NASA Technical Reports Server (NTRS)

    Yen, Shiao-Ping S. (Inventor); Rembaum, Alan (Inventor); Molday, Robert S. (Inventor)

    1977-01-01

    Biocompatible polymeric microspheres having an average diameter below about 3 microns and having density at least 15% greater or lesser than organic cells and having covalent binding sites are provided in accordance with this invention. The microspheres are obtained by copolymerizing a hydroxy or amine substituted acrylic monomer such as hydroxyethylmethacrylate with a light or dense comonomer such as a fluoromonomer. A lectin or antibody is bound to the hydroxy or amine site of the bead to provide cell specificity. When added to a cell suspension the marked bead will specifically label the cell membrane by binding to specific receptor sites thereon. The labelled membrane can then be separated by density gradient centrifugation.

  8. Quercetin induced apoptosis in association with death receptors and fludarabine in cells isolated from chronic lymphocytic leukaemia patients

    PubMed Central

    Russo, M; Spagnuolo, C; Volpe, S; Mupo, A; Tedesco, I; Russo, G-L

    2010-01-01

    Background: Quercetin is a flavonoid naturally present in food and beverages belonging to the large class of phytochemicals with potential anti-cancer properties. Here, we investigated the ability of quercetin to sensitise primary cells from chronic lymphocytic leukaemia (CLL) to death receptor (DR) agonists, recombinant TNF-related-apoptosis-inducing ligand (rTRAIL) and anti-CD95, and to fludarabine, a widely used chemotherapeutic drug against CLL. Methods: Peripheral white blood cells were isolated from patients and incubated with medium containing 50 ng ml anti-CD95 agonist antibody; 10 ng ml recombinant TRAIL; 10–25 μM quercetin and 3.5–14 μM fludarabine. Neutral Red assay was used to measure cell viability, where as apoptosis was assessed by determining caspase-3 activity, exposure to Annexin V and PARP fragmentation. Results: Quercetin significantly enhanced anti-CD95- and rTRAIL-induced cell death as shown by decreased cell viability, increased caspase-3 and -9 activities, and positivity to Annexin V. In addition, association of quercetin with fludarabine increases the apoptotic response in CLL cells of about two-fold compared with quercetin monotreatment. Conclusion: This work shows that resistance to DR- and fludarabine-induced cell death in leukaemic cells isolated from CLL patients can be ameliorated or bypassed by the combined treatment with quercetin. Considering the low toxicity of the molecule, our study results are in favour of a potential use of quercetin in adjuvant chemotherapy in combination with other drugs. PMID:20648016

  9. In vitro digestion and lactase treatment influence uptake of quercetin and quercetin glucoside by the Caco-2 cell monolayer

    PubMed Central

    Boyer, Jeanelle; Brown, Dan; Liu, Rui Hai

    2005-01-01

    Background Quercetin and quercetin glycosides are widely consumed flavonoids found in many fruits and vegetables. These compounds have a wide range of potential health benefits, and understanding the bioavailability of flavonoids from foods is becoming increasingly important. Methods This study combined an in vitro digestion, a lactase treatment and the Caco-2 cell model to examine quercetin and quercetin glucoside uptake from shallot and apple homogenates. Results The in vitro digestion alone significantly decreased quercetin aglycone recovery from the shallot digestate (p < 0.05), but had no significant effect on quercetin-3-glucoside recovery (p > 0.05). Digestion increased the Caco-2 cell uptake of shallot quercetin-4'-glucoside by 2-fold when compared to the non-digested shallot. Despite the loss of quercetin from the digested shallot, the bioavailability of quercetin aglycone to the Caco-2 cells was the same in both the digested and non-digested shallot. Treatment with lactase increased quercetin recovery from the shallot digestate nearly 10-fold and decreased quercetin-4'-glucoside recovery by more than 100-fold (p < 0.05), but had no effect on quercetin recovery from apple digestates. Lactase treatment also increased shallot quercetin bioavailability to the Caco-2 cells approximately 14-fold, and decreased shallot quercetin-4'-glucoside bioavailability 23-fold (p < 0.05). These Caco-2 cells had lactase activity similar to that expressed by a lactose intolerant human. Conclusions The increase in quercetin uptake following treatment with lactase suggests that dietary supplementation with lactase may increase quercetin bioavailability in lactose intolerant humans. Combining the digestion, the lactase treatment and the Caco-2 cell culture model may provide a reliable in vitro model for examining flavonoid glucoside bioavailability from foods. PMID:15644141

  10. Oral Delivery of a High Quercetin Payload Nanosized Emulsion: In Vitro and In Vivo Activity Against B16-F10 Melanoma.

    PubMed

    Dora, Cristiana Lima; Silva, Luis Felipe Costa; Mazzarino, Leticia; Siqueira, Jarbas Mota; Fernandes, Daniel; Pacheco, Leticia Kramer; Maioral, Mariana Franzoni; Santos-Silva, Maria Claudia; Baischl, Ana Luiza Muccillo; Assreuy, Jamil; Lemos-Senna, Elenara

    2016-02-01

    Quercetin is a natural compound that has several biological activities including anticancer activity. However, the use of this drug has been limited mostly because of its poor water solubility and low bioavailability. Therefore, the development of quercetin-loaded nanocarrier systems may be considered a promising advance to exploit its therapeutic properties in clinical setting including cancer treatment. This study evaluates the effect of orally administered nanosized emulsion containing quercetin (QU-NE) on the cytotoxicity activity against B16-F10 cells in vitro, and on subcutaneous melanoma in mice inoculated with B16-F1O cells. In vivo experiments, also evaluate the co-administration of quercetin with cisplatin in order to predict synergic effects and the renal and hepatic toxicity. The nanocarriers were prepared through the hot solvent diffusion associated with the phase inversion temperature methods. In vitro study showed reduction of cell viability in a concentration-depend manner for free quercetin and QU-NE. In vivo study, quercetin either as a free drug or colloidal dispersion was administrated at a dose of 5 mg kg(-1) twice a week for 17 days via oral route. Cisplatin was administrated at dose of 1 mg kg(-1) once a week intraperitoneally. Free quercetin and QU-NE reduced tumor growth, however, the reduction observed for QU-NE (P < 0.001 vs. control) was significantly higher than free quercetin (P < 0.05 vs. control). The association of both drugs did not show synergic effect. Besides, no renal or hepatic toxicities were observed after administration of free quercetin and QU-NE. These results suggest that an improvement in the oral bioavailability of quercetin occurred when this compound was dissolved in the oily phase of a nanosized emulsion, indicating that it might have a potential application in the treatment of melanoma. PMID:27433577

  11. The Flavonoid Quercetin Reverses Pulmonary Hypertension in Rats

    PubMed Central

    Moreno, Enrique; Moral-Sanz, Javier; Barreira, Bianca; Galindo, Pilar; Pandolfi, Rachele; Jimenez, Rosario; Moreno, Laura; Cogolludo, Angel; Duarte, Juan; Perez-Vizcaino, Francisco

    2014-01-01

    Quercetin is a dietary flavonoid which exerts vasodilator, antiplatelet and antiproliferative effects and reduces blood pressure, oxidative status and end-organ damage in humans and animal models of systemic hypertension. We hypothesized that oral quercetin treatment might be protective in a rat model of pulmonary arterial hypertension. Three weeks after injection of monocrotaline, quercetin (10 mg/kg/d per os) or vehicle was administered for 10 days to adult Wistar rats. Quercetin significantly reduced mortality. In surviving animals, quercetin decreased pulmonary arterial pressure, right ventricular hypertrophy and muscularization of small pulmonary arteries. Classic biomarkers of pulmonary arterial hypertension such as the downregulated expression of lung BMPR2, Kv1.5, Kv2.1, upregulated survivin, endothelial dysfunction and hyperresponsiveness to 5-HT were unaffected by quercetin. Quercetin significantly restored the decrease in Kv currents, the upregulation of 5-HT2A receptors and reduced the Akt and S6 phosphorylation. In vitro, quercetin induced pulmonary artery vasodilator effects, inhibited pulmonary artery smooth muscle cell proliferation and induced apoptosis. In conclusion, quercetin is partially protective in this rat model of PAH. It delayed mortality by lowering PAP, RVH and vascular remodeling. Quercetin exerted effective vasodilator effects in isolated PA, inhibited cell proliferation and induced apoptosis in PASMCs. These effects were associated with decreased 5-HT2A receptor expression and Akt and S6 phosphorylation and partially restored Kv currents. Therefore, quercetin could be useful in the treatment of PAH. PMID:25460361

  12. Synergistic neurotoxicity induced by methylmercury and quercetin in mice

    PubMed Central

    Martins, Roberta de P.; Braga, Hugo de C.; da Silva, Aline P.; Dalmarco, Juliana B.; de Bem, Andreza F.; dos Santos, Adair Roberto S.; Dafre, Alcir L.; Pizzolatti, Moacir G.; Latini, Alexandra; Aschner, Michael; Farina, Marcelo

    2010-01-01

    Methylmercury (MeHg) is a highly neurotoxic pollutant, whose mechanisms of toxicity are related to its pro-oxidative properties. A previous report showed under in vivo conditions the neuroprotective effects of plants of the genus Polygala against MeHg-induced neurotoxicity. Moreover, the flavonoid quercetin, isolated from Polygala sabulosa, displayed beneficial effects against MeHg-induced oxidative damage under in vitro conditions. In this study, we sought for potential beneficial effects of quercetin against the neurotoxicity induced by MeHg in Swiss female mice. Animals were divided into six experimental groups: control, quercetin low dose (5 mg/Kg), quercetin high dose (50 mg/Kg), MeHg (40 mg/L, in tap water), MeHg + quercetin low dose, and MeHg + quercetin high dose. After the treatment (21 days), a significant motor deficit was observed in MeHg + quercetin groups. Biochemical parameters related to oxidative stress showed that the simultaneous treatment with quercetin and MeHg caused a higher cerebellar oxidative damage when compared to the individual exposures. MeHg plus quercetin elicited a higher cerebellar lipid peroxidation than MeHg or quercetin alone. The present results indicate that under in vivo conditions quercetin and MeHg cause additive pro-oxidative effects toward the mice cerebellum and that such phenomenon is associated with the observed motor deficit. PMID:19141311

  13. Cell specific, variable density, polymer microspheres

    NASA Technical Reports Server (NTRS)

    Yen, Shiao-Ping S. (Inventor); Rembaum, Alan (Inventor); Molday, Robert S. (Inventor)

    1978-01-01

    Biocompatible polymeric microspheres having an average diameter below about 3 microns and having a density at least 15% greater or lesser than organic cells and having covalent binding sites are provided in accordance with this invention. The microspheres are obtained by copolymerizing a hydroxy or amine substituted acrylic monomer such as hydroxyethylmethacrylate with a light or dense comonomer such as a fluoromonomer. A lectin or antibody is bound to the hydroxy or amine site of the bead to provide cell specificity. When added to a cell suspension the marked bead will specifically label the cell membrane by binding to specific receptor sites thereon. The labelled membrane can then be separated by density gradient centrifugation.

  14. Cell-Specific Cardiac Electrophysiology Models

    PubMed Central

    Groenendaal, Willemijn; Ortega, Francis A.; Kherlopian, Armen R.; Zygmunt, Andrew C.; Krogh-Madsen, Trine; Christini, David J.

    2015-01-01

    The traditional cardiac model-building paradigm involves constructing a composite model using data collected from many cells. Equations are derived for each relevant cellular component (e.g., ion channel, exchanger) independently. After the equations for all components are combined to form the composite model, a subset of parameters is tuned, often arbitrarily and by hand, until the model output matches a target objective, such as an action potential. Unfortunately, such models often fail to accurately simulate behavior that is dynamically dissimilar (e.g., arrhythmia) to the simple target objective to which the model was fit. In this study, we develop a new approach in which data are collected via a series of complex electrophysiology protocols from single cardiac myocytes and then used to tune model parameters via a parallel fitting method known as a genetic algorithm (GA). The dynamical complexity of the electrophysiological data, which can only be fit by an automated method such as a GA, leads to more accurately parameterized models that can simulate rich cardiac dynamics. The feasibility of the method is first validated computationally, after which it is used to develop models of isolated guinea pig ventricular myocytes that simulate the electrophysiological dynamics significantly better than does a standard guinea pig model. In addition to improving model fidelity generally, this approach can be used to generate a cell-specific model. By so doing, the approach may be useful in applications ranging from studying the implications of cell-to-cell variability to the prediction of intersubject differences in response to pharmacological treatment. PMID:25928268

  15. The sorption of quercetin by high-basicity anion exchangers

    NASA Astrophysics Data System (ADS)

    Udalova, N. A.; Karpov, S. I.; Selemenev, V. F.; Sharmar, I. A.

    2009-06-01

    The sorption of quercetin on anionites with various porosities in the OH- and Cl- forms was studied under static conditions. The equilibrium (distribution coefficients K p) and kinetic (effective diffusion coefficients D eff) parameters of quercetin sorption on AV-17-2P and AV-17-6M anionites in the Cl- and OH- forms were calculated. The mechanism of quercetin interactions with the anion exchangers was studied by electron microscopy and IR spectroscopy.

  16. Rutin and total quercetin content in amaranth (Amaranthus spp.).

    PubMed

    Kalinova, Jana; Dadakova, Eva

    2009-03-01

    The aim of the study was to confirm the presence of rutin, one of the most common quercetin glycosides, and other quercetin derivatives in plants of genus Amaranthus, to investigate the influence of the species and variety on rutin distribution in the plant and content changes during growing season. The rutin content was determined by micellar electrokinetic capillary chromatography in individual plant parts at the beginning of the growth, at the flowering stage and at the maturity stage of five Amaranthus species. The total quercetin content was determined by micellar electrokinetic capillary chromatography too. The rutin content in amaranth ranged from 0.08 (in seeds) to 24.5 g/kg dry matter (in leaves). Comparison of the determined total quercetin content and the calculated content of quercetin released from rutin did not prove important presence of quercetin or other quercetin derivatives than rutin. Only amaranth leaves sampled at the maturity stage probably contained quercetin or quercetin derivatives. Significant differences in the rutin content were established among species and as well varieties. Amaranthus hybrid and A. cruentus were the best sources of rutin. PMID:19067170

  17. The reversibility of the glutathionyl-quercetin adduct spreads oxidized quercetin-induced toxicity

    SciTech Connect

    Boots, Agnes W. . E-mail: a.boots@farmaco.unimaas.nl; Balk, Jiska M.; Bast, Aalt; Haenen, Guido R.M.M.

    2005-12-16

    Quercetin is one of the most prominent dietary antioxidants. During its antioxidant activity, quercetin becomes oxidized into its o-quinone/quinone methide QQ. QQ is toxic since it instantaneously reacts with thiols of, e.g., proteins. In cells, QQ will initially form an adduct with glutathione (GSH), giving GSQ. We have found that GSQ is not stable; it dissociates continuously into GSH and QQ with a half life of 2 min. Surprisingly, GSQ incubated with 2-mercapto-ethanol (MSH), a far less reactive thiol, results in the conversion of GSQ into the MSH-adduct MSQ. A similar conversion of GSQ into relatively stable protein thiol-quercetin adducts is expected. With the dithiol dihydrolipoic acid (L(SH){sub 2}), quercetin is formed out of GSQ. These results indicate that GSQ acts as transport and storage of QQ. In that way, the initially highly focussed toxicity of QQ is dispersed by the formation of GSQ that finally spreads QQ-induced toxicity, probably even over cells.

  18. Bovine Serum Albumin Nanoparticles Containing Quercetin: Characterization and Antioxidant Activity.

    PubMed

    Antônio, Emilli; Khalil, Najeh Maissar; Mainardes, Rubiana Mara

    2016-02-01

    Quercetin is a flavonoid reported as anti-allergic, anti-inflammatory, antiplatelet, anti-microbial, antioxidant, antineurodegenerative and antitumoral. However, due to its low water solubility, its efficacy is restricted. Nanotechnology can be an importante tool to improve the quercetin properties and increase its bioavailability. In this study, bovine serum albumin (BSA) nanoparticles containing quercetin were developed by desolvation technique, characterized the mean particle size, polydispersity, zeta potential, encapsulation efficiency, physical state of drug in nanoparticles and drug release profile as well as their antioxidant activity was evaluated. The influence of glutaraldehyde percentage in nanoparticles properties was evaluated and did not influence the nanoparticles parameters. Nanoparticles presented a mean size around 130 nm and encapsulation efficiency around 85%. Results from X-ray diffractometry showed that the crystal of the drug was converted to an amorphous state in polymeric matrix. Quercetin release profile demonstrated a biphasic pattern and after 96 h approximately 18% of drug was released. Kinetic models demonstrated that the quercetin release followed a second-order model and the release was governed by Fickian diffusion. After 96 h, quercetin-loaded nanoparticles were more effective than free quercetin for scanvenger of radical ABTS + and hypochlorous acid. BSA nanoparticles represents potential carriers for improve quercetin properties. PMID:27433585

  19. Synthesis of methylated quercetin derivatives and their reversal activities on P-gp- and BCRP-mediated multidrug resistance tumour cells.

    PubMed

    Yuan, Jian; Wong, Iris L K; Jiang, Tao; Wang, Si Wen; Liu, Tao; Wen, Bin Jin; Chow, Larry M C; Wan Sheng, Biao

    2012-08-01

    Three methylated quercetins and a series of O-3 substituted 5,7,3',4'-tetra-O-methylated quercetin derivatives have been synthesized and evaluated on the modulating activity of P-gp, BCRP and MRP1 in cancer cell lines. Compound 17 (with a 2-((4-methoxybenzoyl)oxy)ethyl at O-3) is the most potent P-gp modulator. Three derivatives, compound 9 (3,7,3',4'-tetra-O-methylated quercetin), compound 14 (with a 2-((3-oxo-3-(3,4,5trimethoxyphenyl)prop-1-en-1-yl)oxy)ethyl at O-3) and compound 17, consistently exhibited promising BCRP-modulating activity. Interestingly, compound 17 was found to be equipotent against both P-gp and BCRP. Importantly, these synthetic quercetin derivatives did not exhibit any inherent cytotoxicity to cancer cell lines or normal mouse fibroblast cell lines. These quercetin derivatives can be employed as safe and effective modulators of P-gp- or BCRP-mediated drug resistance in cancer. PMID:22743241

  20. Cell specific cytotoxicity and uptake of graphene nanoribbons.

    PubMed

    Mullick Chowdhury, Sayan; Lalwani, Gaurav; Zhang, Kevin; Yang, Jeong Y; Neville, Kayla; Sitharaman, Balaji

    2013-01-01

    . Additional analysis indicates that this increased uptake is the dominant cause of the significantly higher toxicity exhibited by HeLa cells. The results suggest that water-solubilized O-GNR-PEG-DSPEs have a heterogenous cell-specific cytotoxicity, and have significantly different cytotoxicity profile compared to graphene nanoparticles prepared by the modified Hummer's method (graphene nanoparticles prepared by oxidation of graphite, and its mechanical exfoliation) or its variations. PMID:23072942

  1. Cell Specific Cytotoxicity and Uptake of Graphene Nanoribbons

    PubMed Central

    Chowdhury, Sayan Mullick; Lalwani, Gaurav; Zhang, Kevin; Yang, Jeong Yun; Neville, Kayla; Sitharaman, Balaji

    2012-01-01

    types. Additional analysis indicates that this increased uptake is the dominant cause of the significantly higher toxicity exhibited by HeLa cells. The results suggest that water-solubilized O-GNR-PEG-DSPEs have a heterogeneous cell-specific cytotoxicity, and have significantly different cytotoxicity profile compared to graphene nanoparticles prepared by the modified Hummer’s method (graphene nanoparticles prepared by oxidation of graphite, and its mechanical exfoliation) or its variations. PMID:23072942

  2. Quercetin attenuates doxorubicin cardiotoxicity by modulating Bmi-1 expression

    PubMed Central

    Dong, Qinghua; Chen, Long; Lu, Qunwei; Sharma, Sherven; Li, Lei; Morimoto, Sachio; Wang, Guanyu

    2014-01-01

    Background and Purpose Doxorubicin-based chemotherapy induces cardiotoxicity, which limits its clinical application. We previously reported the protective effects of quercetin against doxorubicin-induced hepatotoxicity. In this study, we tested the effects of quercetin on the expression of Bmi-1, a protein regulating mitochondrial function and ROS generation, as a mechanism underlying quercetin-mediated protection against doxorubicin-induced cardiotoxicity. Experimental Approach Effects of quercetin on doxorubicin-induced cardiotoxicity was evaluated using H9c2 cardiomyocytes and C57BL/6 mice. Changes in apoptosis, mitochondrial function, oxidative stress and related signalling were evaluated in H9c2 cells. Cardiac function, serum enzyme activity and reactive oxygen species (ROS) generation were measured in mice after a single injection of doxorubicin with or without quercetin pre-treatment. Key Results In H9c2 cells, quercetin reduced doxorubicin-induced apoptosis, mitochondrial dysfunction, ROS generation and DNA double-strand breaks. The quercetin-mediated protection against doxorubicin toxicity was characterized by decreased expression of Bid, p53 and oxidase (p47 and Nox1) and by increased expression of Bcl-2 and Bmi-1. Bmi-1 siRNA abolished the protective effect of quercetin against doxorubicin-induced toxicity in H9c2 cells. Furthermore, quercetin protected mice from doxorubicin-induced cardiac dysfunction that was accompanied by reduced ROS levels and lipid peroxidation, but enhanced the expression of Bmi-1 and anti-oxidative superoxide dismutase. Conclusions and Implications Our results demonstrate that quercetin decreased doxorubicin-induced cardiotoxicity in vitro and in vivo by reducing oxidative stress by up-regulation of Bmi-1 expression. The findings presented in this study have potential applications in preventing doxorubicin-induced cardiomyopathy. PMID:24902966

  3. Dose-response to 3 months of quercetin-containing supplements on metabolite and quercetin conjugate profile in adults.

    PubMed

    Cialdella-Kam, Lynn; Nieman, David C; Sha, Wei; Meaney, Mary Pat; Knab, Amy M; Shanely, R Andrew

    2013-06-01

    Quercetin, a flavonol in fruits and vegetables, has been demonstrated to have antioxidant, anti-inflammatory and immunomodulating influences. The purpose of the present study was to determine if quercetin, vitamin C and niacin supplements (Q-500 = 500 mg/d of quercetin, 125 mg/d of vitamin C and 5 mg/d of niacin; Q-1000 = 1000 mg/d of quercetin, 250 mg/d of vitamin C and 10 mg/d of niacin) would alter small-molecule metabolite profiles and serum quercetin conjugate levels in adults. Healthy adults (fifty-eight women and forty-two men; aged 40-83 years) were assigned using a randomised double-blinded placebo-controlled trial to one of three supplement groups (Q-1000, Q-500 or placebo). Overnight fasted blood samples were collected at 0, 1 and 3 months. Quercetin conjugate concentrations were measured using ultra-performance liquid chromatography (UPLC)-MS/MS, and metabolite profiles were measured using two MS platforms (UPLC-quadrupole time-of-flight MS (TOFMS) and GC-TOFMS). Statistical procedures included partial least square discriminant analysis (PLS-DA) and linear mixed model analysis with repeated measures. After accounting for age, sex and BMI, quercetin supplementation was associated with significant shifts in 163 metabolites/quercetin conjugates (false discovery rate, P<0·05). The top five metabolite shifts were an increase in serum guaiacol, 2-oxo-4-methylthiobutanoic acid, allocystathionine and two bile acids. Inflammatory and oxidative stress metabolites were not affected. PLS-DA revealed a clear separation only between the 1000 mg/d and placebo groups (Q(2)Y = 0·763). The quercetin conjugate, isorhamnetin-3-glucuronide, had the highest concentration at 3 months followed by quercetin-3-glucuronide, quercetin-3-sulphate and quercetin diglucuronide. In human subjects, long-term quercetin supplementation exerts disparate and wide-ranging metabolic effects and changes in quercetin conjugate concentrations. Metabolic shifts were apparent at the 1000 mg

  4. Cell-specific nitrogen responses mediate developmental plasticity

    PubMed Central

    Gifford, Miriam L.; Dean, Alexis; Gutierrez, Rodrigo A.; Coruzzi, Gloria M.; Birnbaum, Kenneth D.

    2008-01-01

    The organs of multicellular species consist of cell types that must function together to perform specific tasks. One critical organ function is responding to internal or external change. Some cell-specific responses to changes in environmental conditions are known, but the scale of cell-specific responses within an entire organ as it perceives an environmental flux has not been well characterized in plants or any other multicellular organism. Here, we use cellular profiling of five Arabidopsis root cell types in response to an influx of a critical resource, nitrogen, to uncover a vast and predominantly cell-specific response. We show that cell-specific profiling increases sensitivity several-fold, revealing highly localized regulation of transcripts that were largely hidden from previous global analyses. The cell-specific data revealed responses that suggested a coordinated developmental response in distinct cell types or tissues. One example is the cell-specific regulation of a transcriptional circuit that we showed mediates lateral root outgrowth in response to nitrogen via microRNA167, linking small RNAs to nitrogen responses. Together, these results reveal a previously cryptic component of cell-specific responses to nitrogen. Thus, the results make an important advance in our understanding of how multicellular organisms cope with environmental change at the cell level. PMID:18180456

  5. Antioxidative and antiinflammatory activities of quercetin-loaded silica nanoparticles.

    PubMed

    Lee, Ga Hyun; Lee, Sung June; Jeong, Sang Won; Kim, Hyun-Chul; Park, Ga Young; Lee, Se Geun; Choi, Jin Hyun

    2016-07-01

    Utilizing the biological activities of compounds by encapsulating natural components in stable nanoparticles is an important strategy for a variety of biomedical and healthcare applications. In this study, quercetin-loaded silica nanoparticles were synthesized using an oil-in-water microemulsion method, which is a suitable system for producing functional nanoparticles of controlled size and shape. The resulting quercetin-loaded silica nanoparticles were spherical, highly monodispersed, and stable in an aqueous system. Superoxide radical scavenging effects were found for the quercetin-loaded silica nanoparticles as well as free quercetin. The quercetin-loaded silica nanoparticles showed cell viability comparable to that of the controls. The amounts of proinflammatory cytokines produced by macrophages, such as interleukin 1 beta, interleukin 6, and tumor necrosis factor alpha, were reduced significantly for the quercetin-loaded silica nanoparticles. These results suggest that the antioxidative and antiinflammatory activities of quercetin are maintained after encapsulation in silica. Silica nanoparticles can be used for the effective and stable incorporation of biologically active natural components into composite biomaterials. PMID:27038916

  6. Quercetin-imprinted polymer for anthocyanin extraction from mangosteen pericarp.

    PubMed

    Piacham, Theeraphon; Isarankura-Na-Ayudhya, Chartchalerm; Prachayasittikul, Virapong

    2015-06-01

    Molecular imprinting is a facilitative technology for the production of artificial receptors possessing great endurance with high specificity toward target molecules of interest. The polymers are commonly applied for separation or analysis of substances of interest. In this study, we prepared molecularly imprinted polymers for the purpose of binding specifically to quercetin and related compounds. Quercetin was used as the template molecule, 4-vinylpyridine (4-VP) as the functional monomer, ethylene glycol dimethacrylate (EDMA) as the cross-linking monomer, azobisisobutyronitrile (AIBN) as the polymerization initiator and ethanol as the porogenic solvent. Such 4-VP-based imprinted polymer was found to bind the template molecule greater than that of the control polymer with an approximate 2 folds higher binding using 20mg of polymer in the optimal solvent, ethanol:water (4:1v/v). Quercetin-imprinted polymer (QIP) was found to bind well against its template; approximately 1mg/g polymer. In addition, QIP was applied to bind anthocyanin from the crude extract of mangosteen pericarp. The binding capacity of quercetin-MIP toward anthocyanin was approximately 0.875mg per gram of polymer. This result indicated that quercetin-MIP showed its specific binding to quercetin and related compound particularly anthocyanin. In conclusion, we have demonstrated the successful preparation and utilization of molecularly imprinted polymer for the specific recognition of quercetin as well as structurally related anthocyanins from the mangosteen pericarp with enhanced and robust performance. PMID:25842116

  7. Quercetin Affects Erythropoiesis and Heart Mitochondrial Function in Mice.

    PubMed

    Ruiz, Lina M; Salazar, Celia; Jensen, Erik; Ruiz, Paula A; Tiznado, William; Quintanilla, Rodrigo A; Barreto, Marlen; Elorza, Alvaro A

    2015-01-01

    Quercetin, a dietary flavonoid used as a food supplement, showed powerful antioxidant effects in different cellular models. However, recent in vitro and in vivo studies in mammals have suggested a prooxidant effect of quercetin and described an interaction with mitochondria causing an increase in O2 (∙-) production, a decrease in ATP levels, and impairment of respiratory chain in liver tissue. Therefore, because of its dual actions, we studied the effect of quercetin in vivo to analyze heart mitochondrial function and erythropoiesis. Mice were injected with 50 mg/kg of quercetin for 15 days. Treatment with quercetin decreased body weight, serum insulin, and ceruloplasmin levels as compared with untreated mice. Along with an impaired antioxidant capacity in plasma, quercetin-treated mice showed a significant delay on erythropoiesis progression. Heart mitochondrial function was also impaired displaying more protein oxidation and less activity for IV, respectively, than no-treated mice. In addition, a significant reduction in the protein expression levels of Mitofusin 2 and Voltage-Dependent Anion Carrier was observed. All these results suggest that quercetin affects erythropoiesis and mitochondrial function and then its potential use as a dietary supplement should be reexamined. PMID:26106459

  8. Enhancing oral bioavailability of quercetin using novel soluplus polymeric micelles

    NASA Astrophysics Data System (ADS)

    Dian, Linghui; Yu, Enjiang; Chen, Xiaona; Wen, Xinguo; Zhang, Zhengzan; Qin, Lingzhen; Wang, Qingqing; Li, Ge; Wu, Chuanbin

    2014-12-01

    To improve its poor aqueous solubility and stability, the potential chemotherapeutic drug quercetin was encapsulated in soluplus polymeric micelles by a modified film dispersion method. With the encapsulation efficiency over 90%, the quercetin-loaded polymeric micelles (Qu-PMs) with drug loading of 6.7% had a narrow size distribution around mean size of 79.00 ± 2.24 nm, suggesting the complete dispersibility of quercetin in water. X-ray diffraction (XRD) patterns illustrated that quercetin was in amorphous or molecular form within PMs. Fourier transform infrared spectroscopy (FTIR) indicated that quercetin formed intermolecular hydrogen bonding with carriers. An in vitro dialysis test showed the Qu-PMs possessed significant sustained-release property, and the formulation was stable for at least 6 months under accelerated conditions. The pharmacokinetic study in beagle dogs showed that absorption of quercetin after oral administration of Qu-PMs was improved significantly, with a half-life 2.19-fold longer and a relative oral bioavailability of 286% as compared to free quercetin. Therefore, these novel soluplus polymeric micelles can be applied to encapsulate various poorly water-soluble drugs towards a development of more applicable therapeutic formulations.

  9. Comparison of the bioavailability of quercetin and catechin in rats.

    PubMed

    Manach, C; Texier, O; Morand, C; Crespy, V; Régérat, F; Demigné, C; Rémésy, C

    1999-12-01

    Quercetin and catechin are present in noticeable amounts in human diet and these polyphenolic compounds are supposed to exert beneficial effects on human health. However, their metabolic fates in the organism have never been compared. In the present study, rats were fed a 0.25% quercetin or a 0.25% catechin diet. Quercetin and catechin metabolites were analyzed in plasma and liver samples by high-performance liquid chromatography coupled to an ultraviolet or a multielectrode coulometric detection. All plasma metabolites were present as conjugated forms, but catechin metabolites were mainly constituted by glucuronidated derivatives, whereas quercetin metabolites were sulfo- and glucurono-sulfo conjugates. Quercetin was more intensively methylated than catechin in plasma. The plasma quercetin metabolites are well maintained during the postabsorptive period (approximately 50 microM), whereas the concentration of catechin metabolites dropped dramatically between 12- and 24-h after an experimental meal (from 38.0 to 4.5 microM). In the liver, the concentrations of quercetin and catechin derivatives were lower than in plasma, and no accumulation was observed when the rats were adapted for 14 d to the supplemented diets. The hepatic metabolites were intensively methylated (90-95%), but in contrast to plasma, some free aglycones could be detected. Thus, it clearly appears that studies dealing with the biological impact of these polyphenols should take into account the feature of their bioavailability, particularly the fact that their circulating metabolites are conjugated derivatives. PMID:10641719

  10. [Study of quantum-pharmacological chemical characteristics of quercetin].

    PubMed

    Zahorodnyĭ, M I

    2007-01-01

    It was established in the previous studies that quercetin prevented the development and caused faster regression of ulcers, petechia and anabroses in rats, which were induced by diclofenac taking. In the group of patients taking diclofenac together with quercetin, the ulcers and dyspeptic events were less found. The application of quercetin normalizes the function and metabolism of cartilage tissue of rabbits with an experimental osteoarthrosis and in patients with osteoartrosis. Quantum-chemical properties of molecule quercetin were studied using the methods of molecular mechanics MM+ and ab initio 6-31G*, and also semiempirical method. The following indices were investigated: distance between atoms (A), the distribution of electronic density of only external valency electrons, distribution of electrostatic potential; common energy of the exertion of molecule (kkal/mmol); binding energy (kkal/mmol); electron energy (kkal/mmol); energy of nucleus-nucleus interaction (kkal/mmol); formation heat (kkal/mmol); atomic charge (eB); value of the dipole moment of molecule (D); localization and energy of highest occupied orbital (HOMO) and the lowest unoccupied (LUMO) molecular orbital (eB) of quercetin miolecule; the value of absolute rigidity of chemical structure of bioflavonoid. It was shown, that bioflavonoid quercetin belongs to mild reagents, has nucleophilic properties, can react with alkaline, unsaturated and aromatic compounds,. Polar substitutes in the quercetine molecule influence on the distribution of superficial valency electrons and localization of HOMO and LUMO. The energy value of quercetin LUMO enables us to refer quercetine to the reducing agent and it is illustrated by antioxidant properties of this medicine. PMID:18663944

  11. Proatherogenic macrophage activities are targeted by the flavonoid quercetin.

    PubMed

    Lara-Guzman, Oscar J; Tabares-Guevara, Jorge H; Leon-Varela, Yudy M; Álvarez, Rafael M; Roldan, Miguel; Sierra, Jelver A; Londoño-Londoño, Julian A; Ramirez-Pineda, Jose R

    2012-11-01

    Many studies have demonstrated that the flavonoid quercetin protects against cardiovascular disease (CVD) and related risk factors. Atherosclerosis, the underlying cause of CVD, is also attenuated by oral quercetin administration in animal models. Although macrophages are key players during fatty streak formation and plaque progression and aggravation, little is known about the effects of quercetin on atherogenic macrophages. Here, we report that primary bone marrow-derived macrophages internalized less oxidized low-density lipoprotein (oxLDL) and accumulated less intracellular cholesterol in the presence of quercetin. This reduction of foam cell formation correlated with reduced surface expression of the oxLDL receptor CD36. Quercetin also targeted the lipopolysaccharide-dependent, oxLDL-independent pathway of lipid droplet formation in macrophages. In oxLDL-stimulated macrophages, quercetin inhibited reactive oxygen species production and interleukin (IL)-6 secretion. In a system that evaluated cholesterol crystal-induced IL-1β secretion via nucleotide-binding domain and leucine-rich repeat containing protein 3 inflammasome activation, quercetin also exhibited an inhibitory effect. Dyslipidemic apolipoprotein E-deficient mice chronically treated with intraperitoneal quercetin injections had smaller atheromatous lesions, reduced lipid deposition, and less macrophage and T cell inflammatory infiltrate in the aortic roots than vehicle-treated animals. Serum levels of total cholesterol and the lipid peroxidation product malondialdehyde were also reduced in these mice. Our results demonstrate that quercetin interferes with both key proatherogenic activities of macrophages, namely foam cell formation and pro-oxidant/proinflammatory responses, and these effects may explain the atheroprotective properties of this common flavonoid. PMID:22869926

  12. Quercetin as a prophylactic measure against high altitude cerebral edema.

    PubMed

    Patir, Himadri; Sarada, S K S; Singh, Saumya; Mathew, Titto; Singh, Bhagwat; Bansal, Anju

    2012-08-15

    The present study was undertaken to elucidate the intervention of quercetin against high altitude cerebral edema (HACE) using male Sprague Dawley rats as an animal model. This study was also programmed to compare and correlate the effect of both quercetin (flavonoid) and dexamethasone (steroid) against HACE. Six groups of animals were designed for this experiment, (I) normoxia, (II) hypoxia (25,000 ft, 24 h), (III) normoxia+quercetin (50 mg/kg body wt), (IV) normoxia+dexamethasone (4 mg/kg body wt), (V) hypoxia+quercetin (50 mg/kg body wt), (VI) hypoxia+dexamethasone (4 mg/kg body wt). Quercetin at 50 mg/kg body wt, orally 1h prior to hypoxia exposure, was considered as the optimum dose, due to a significant reduction in the level of brain water content and cerebral transvascular leakage (P < 0.001), as compared to control (24 h hypoxia). Dexamethasone was administered at 4 mg/kg body wt, orally, 1h prior to hypoxia exposure. Both drugs (quercetin and dexamethasone) could efficiently reduce the hypoxia-induced hematological changes. Quercetin was observed to be a more potent antioxidative and anti-inflammatory agent. It blocks nuclear factor kappa-beta (NFκB) more significantly (P < 0.05) than the dexamethasone-administered hypoxia-exposed rats. Histopathological findings demonstrate the absence of an edema and inflammation in the brain sections of quercetin-administered hypoxia-exposed rats. The present study reveals quercetin to be a potent drug against HACE, as it efficiently attenuates inflammation as well as cerebral edema formation without any side effects of steroid therapy (dexamethasone). PMID:22743108

  13. Stage-specific quercetin sulfation in the gut of Mythimna separata larvae (Lepidoptera: Noctuidae).

    PubMed

    Aboshi, Takako; Ishida, Masahiro; Matsushita, Kaori; Hirano, Yunosuke; Nishida, Ritsuo; Mori, Naoki

    2014-01-01

    The metabolism of quercetin was investigated in Mythimna separata larvae. Quercetin 4'-O-sulfate was mainly identified in the frass when 6th instar larvae were fed artificial diets containing 1% quercetin. In the case of the 3rd instar larvae, a larger amount of quercetin was detected in the frass. M. separata larvae had different metabolic strategies for quercetin at different developmental stages. PMID:25036481

  14. Molecular Targets Underlying the Anticancer Effects of Quercetin: An Update.

    PubMed

    Khan, Fazlullah; Niaz, Kamal; Maqbool, Faheem; Ismail Hassan, Fatima; Abdollahi, Mohammad; Nagulapalli Venkata, Kalyan C; Nabavi, Seyed Mohammad; Bishayee, Anupam

    2016-01-01

    Quercetin, a medicinally important member of the flavonoid family, is one of the most prominent dietary antioxidants. It is present in a variety of foods-including fruits, vegetables, tea, wine, as well as other dietary supplements-and is responsible for various health benefits. Numerous pharmacological effects of quercetin include protection against diseases, such as osteoporosis, certain forms of malignant tumors, and pulmonary and cardiovascular disorders. Quercetin has the special ability of scavenging highly reactive species, such as hydrogen peroxide, superoxide anion, and hydroxyl radicals. These oxygen radicals are called reactive oxygen species, which can cause oxidative damage to cellular components, such as proteins, lipids, and deoxyribonucleic acid. Various oxygen radicals play important roles in pathophysiological and degenerative processes, such as aging. Subsequently, several studies have been performed to evaluate possible advantageous health effects of quercetin and to collect scientific evidence for these beneficial health claims. These studies also gather data in order to evaluate the exact mechanism(s) of action and toxicological effects of quercetin. The purpose of this review is to present and critically analyze molecular pathways underlying the anticancer effects of quercetin. Current limitations and future directions of research on this bioactive dietary polyphenol are also critically discussed. PMID:27589790

  15. Quercetin solubilisation in bile salts: A comparison with sodium dodecyl sulphate.

    PubMed

    Buchweitz, Maria; Kroon, Paul A; Rich, Gillian T; Wilde, Peter J

    2016-11-15

    To understand the bioaccessibility of the flavonoid quercetin we studied its interaction with bile salt micelles. The environmental sensitivity of quercetin's UV-visible absorption spectrum gave information about quercetin partitioning. Two quercetin absorption peaks gave complementary information: Peak A (240-280nm) on the intermicellar phase and Peak B (340-440nm) on the micellar phase. Thus, by altering pH, we showed that only non-ionised quercetin partitions into micelles. We validated our interpretation by studying quercetin's interaction with SDS micelles. Pyrene fluorescence and the quercetin UV-visible spectra show that the adsorption site for pyrene and quercetin in bile salt micelles is more hydrophobic than that for SDS micelles. Also, both quercetin and pyrene reported a higher critical micelle concentration for bile salts than for SDS. Our method of using a flavonoid as an intrinsic probe, is generally applicable to other lipophilic bioactives, whenever they have observable environmental dependent properties. PMID:27283643

  16. Quercetin Protects against Okadaic Acid-Induced Injury via MAPK and PI3K/Akt/GSK3β Signaling Pathways in HT22 Hippocampal Neurons.

    PubMed

    Jiang, Wei; Luo, Tao; Li, Sheng; Zhou, Yue; Shen, Xiu-Yin; He, Feng; Xu, Jie; Wang, Hua-Qiao

    2016-01-01

    Increasing evidence shows that oxidative stress and the hyperphosphorylation of tau protein play essential roles in the progression of Alzheimer's disease (AD). Quercetin is a major flavonoid that has anti-oxidant, anti-cancer and anti-inflammatory properties. We investigated the neuroprotective effects of quercetin to HT22 cells (a cell line from mouse hippocampal neurons). We found that Okadaic acid (OA) induced the hyperphosphorylation of tau protein at Ser199, Ser396, Thr205, and Thr231 and produced oxidative stress to the HT22 cells. The oxidative stress suppressed the cell viability and decreased the levels of lactate dehydrogenase (LDH), superoxide dismutase (SOD), mitochondria membrane potential (MMP) and Glutathione peroxidase (GSH-Px). It up-regulated malondialdehyde (MDA) production and intracellular reactive oxygen species (ROS). In addition, phosphoinositide 3 kinase/protein kinase B/Glycogen synthase kinase3β (PI3K/Akt/GSK3β) and mitogen activated protein kinase (MAPK) were also involved in this process. We found that pre-treatment with quercetin can inhibited OA-induced the hyperphosphorylation of tau protein and oxidative stress. Moreover, pre-treatment with quercetin not only inhibited OA-induced apoptosis via the reduction of Bax, and up-regulation of cleaved caspase 3, but also via the inhibition of PI3K/Akt/GSK3β, MAPKs and activation of NF-κB p65. Our findings suggest the therapeutic potential of quercetin to treat AD. PMID:27050422

  17. Quercetin Protects against Okadaic Acid-Induced Injury via MAPK and PI3K/Akt/GSK3β Signaling Pathways in HT22 Hippocampal Neurons

    PubMed Central

    Li, Sheng; Zhou, Yue; Shen, Xiu-Yin; He, Feng; Xu, Jie; Wang, Hua-Qiao

    2016-01-01

    Increasing evidence shows that oxidative stress and the hyperphosphorylation of tau protein play essential roles in the progression of Alzheimer’s disease (AD). Quercetin is a major flavonoid that has anti-oxidant, anti-cancer and anti-inflammatory properties. We investigated the neuroprotective effects of quercetin to HT22 cells (a cell line from mouse hippocampal neurons). We found that Okadaic acid (OA) induced the hyperphosphorylation of tau protein at Ser199, Ser396, Thr205, and Thr231 and produced oxidative stress to the HT22 cells. The oxidative stress suppressed the cell viability and decreased the levels of lactate dehydrogenase (LDH), superoxide dismutase (SOD), mitochondria membrane potential (MMP) and Glutathione peroxidase (GSH-Px). It up-regulated malondialdehyde (MDA) production and intracellular reactive oxygen species (ROS). In addition, phosphoinositide 3 kinase/protein kinase B/Glycogen synthase kinase3β (PI3K/Akt/GSK3β) and mitogen activated protein kinase (MAPK) were also involved in this process. We found that pre-treatment with quercetin can inhibited OA-induced the hyperphosphorylation of tau protein and oxidative stress. Moreover, pre-treatment with quercetin not only inhibited OA-induced apoptosis via the reduction of Bax, and up-regulation of cleaved caspase 3, but also via the inhibition of PI3K/Akt/GSK3β, MAPKs and activation of NF-κB p65. Our findings suggest the therapeutic potential of quercetin to treat AD. PMID:27050422

  18. Dietary Quercetin Reduces Chemotherapy-Induced Fatigue in Mice

    PubMed Central

    Mahoney, Sara E.; Davis, J. Mark; Murphy, E. Angela; McClellan, Jamie L.; Pena, Marjory M.

    2014-01-01

    Purpose While fatigue is the most commonly reported symptom of chemotherapy, there are currently no effective treatments for chemotherapy-induced fatigue (CIF). We used a mouse model to examine the benefits of quercetin on CIF as measured by voluntary wheel running activity and sought to determine whether quercetin may be associated with a decrease in inflammation and/or anemia. Methods Mice were assigned to 1 of 4 groups: placebo-vehicle (Plac-PBS), placebo-5-fluorouracil (Plac-5FU), quercetin-vehicle (Quer-PBS), or quercetin-5-fluorouracil (Quer-5FU). All mice were given a daily injection of either 60 mg/kg of 5-FU or phosphate buffered saline (PBS) for 5 days. Quercetin (0.02%) treatment was administered in the food 3 days prior to 5-FU administration and for the duration of the experiment (ie, days −2 to 14). A second group of mice was sacrificed at 5 and 14 days post initial injection for assessment of monocyte chemoattractant protein-1 (MCP-1) and anemia. Results Voluntary wheel running was reduced in both the Plac-5FU and Quer-5FU groups following 5-FU injection (P < .05). However, the Quer-5FU group recovered to baseline levels by approximately day 7, whereas the Plac-5FU group remained suppressed. MCP-1 was significantly elevated at 14 days in Plac-5FU (P < .001), but no changes were seen with Quer-5FU. Treatment with 5-FU resulted in anemia at both 5 days and 14 days; however, quercetin blocked this effect at 14 days (P < .001). Conclusion These results demonstrate the beneficial effect of quercetin on improving recovery of voluntary physical activity following 5-FU treatment, which may be linked to a decrease in inflammation and anemia. PMID:24626097

  19. Efficacy of quercetin against chemically induced murine oral squamous cell carcinoma

    PubMed Central

    DROGUETT, DANIEL; CASTILLO, CHRISTIAN; LEIVA, ELBA; THEODULOZ, CRISTINA; SCHMEDA-HIRSCHMANN, GUILLERMO; KEMMERLING, ULRIKE

    2015-01-01

    Oral squamous cell carcinoma (OSCC) is the most common form of head and neck cancer, and oxidative damage is associated with the development of OSCCs. Antioxidants have therefore been proposed for use as chemoprotective agents against different types of cancer. In the present study, the effect of the antioxidant quercetin, administered at doses of 10 and 100 mg/kg/day, was investigated in an experimental murine model of 4-nitroquinoline 1-oxide (4-NQO)-induced carcinogenesis. The survival of the treated animals, the plasmatic levels of reduced glutathione and the type and severity of lesions (according the International Histological Classification of Tumors and Bryne's Multifactorial Grading System for the Invasive Tumor Front) were assessed. Additionally, the organization of the extracellular matrix was analyzed by carbohydrate and collagen histochemistry, and immunohistochemistry was used to assess the expression of the tumor markers proliferating cell nuclear antigen and mutated p53. The results indicate that, despite the promising effect of quercetin in other studies, this drug is ineffective as a chemoprotective agent against 4-NQO-induced OSCC in mice at the assayed doses. PMID:26622865

  20. Quercetin and quercetin 3-O-glycosides from Bauhinia longifolia (Bong.) Steud. show anti-Mayaro virus activity

    PubMed Central

    2014-01-01

    Background The arthropod-borne Mayaro virus (MAYV) causes ‘Mayaro fever’, a disease of medical significance, primarily affecting individuals in permanent contact with forested areas in tropical South America. Recently, MAYV has attracted attention due to its likely urbanization. Currently, there are no licensed drugs against most mosquito-transmitted viruses. Here, we investigated the in vitro anti-MAYV activity of the flavonoids quercetin and its derivatives from the Brazilian shrub Bauhinia longifolia (Bong.) Steud. Methods Flavonoids were purified by chromatographic fractionation from leaf extracts of B. longifolia and chemically identified as quercetin and quercetin glycosides using spectroscopic techniques. Cytotoxicity of purified flavonoids and of EtOAc- and n-BuOH-containing flavonoid mixtures was measured by the dye-uptake assay while their antiviral activity was evaluated by a virus yield inhibition assay. Results The following flavonoids were purified from B. longifolia leaves: non-glycosylated quercetin and its glycosides guaijaverin, quercitrin, isoquercitrin, and hyperin. EtOAc and n-BuOH fractions containing these flavonoids demonstrated the highest antiviral activity of all tested substances, while quercetin had the highest antiviral activity amongst purified flavonoids. Quercetin, EtOAc, or n-BuOH fractions inhibited MAYV production by more than 90% at 25 μg/mL, displaying a stronger antiviral effect than the licensed antiviral ribavirin. A mixture of the isomers isoquercitrin and hyperin had a modest antiviral effect (IC90 = 104.9), while guaijaverin and quercitrin did not show significant antiviral activity. Conclusions B. longifolia is a good source of flavonoids with anti-Mayaro virus activity. This is the first report of the activity of quercetin and its derivatives against an alphavirus. PMID:24678592

  1. Inhibitory effect of quercetin on periodontal pathogens in vitro.

    PubMed

    Geoghegan, F; Wong, R W K; Rabie, A B M

    2010-06-01

    Actinobacillus actinomycetemcomitans (Aa) and Porphyromonas gingivalis (Pg) are bacteria strongly associated with early onset, progressive and refractory periodontal disease and associated alveolar bone loss. Quercetin is a flavonoid found in many foods including apples, onions and tea. The aim of this study was to evaluate the effect of quercetin on in vitro growth of periodontal pathogens Aa and Pg. For comparison, quercetin's effect on several oral microbes was also evaluated. Different concentrations of quercetin solution were added to calibrated suspensions of Aa and Pg. All suspensions were incubated for 1, 3, 6, and 24 h in an anaerobic chamber at 37 degrees C. At each time point, selected dilutions from each culture broth were plated on blood agar plates. Colonies appearing on blood agar plates were visually counted on 3 days for Aa and 5 days for Pg. Minimum inhibitory concentrations of both periodontal pathogens were also determined. Both periodontal bacteria showed a significant decrease (p < 0.05) in viable counts after 1 h. No colony forming units of Pg could be observed after 24 h. The results suggest that quercetin possesses significant antimicrobial properties on periodontal pathogens in vitro. PMID:19957242

  2. Protective Effect of Quercetin on Posttraumatic Cardiac Injury

    PubMed Central

    Jing, Zehao; Wang, Zhuorun; Li, Xiujie; Li, Xintao; Cao, Tingting; Bi, Yue; Zhou, Jicheng; Chen, Xu; Yu, Deqin; Zhu, Liang; Li, Shuzhuang

    2016-01-01

    Quercetin is an important dietary flavonoid present in fruits and vegetables and has attracted attention because of its anti-inflammatory and anti-oxidative properties. Inflammation and oxidative stress play important roles in posttraumatic cardiomyocyte apoptosis, which contributes to secondary cardiac dysfunction. This study investigates the protective effect of quercetin on trauma-induced secondary cardiac injury and the mechanisms involved. Widely accepted nonlethal mechanical trauma models were established. In vivo, cardiomyocyte apoptosis and cardiac dysfunction in rats were assessed using TUNEL staining and a biological mechanic experiment system. In vitro, cell viability, tumour necrosis factor-α (TNF-α), reactive oxygen species (ROS) and [Ca2+]i of H9c2 cells were detected using an MTT assay, ELISA, and 2′,7′-dichlorofluorescin diacetate and fluo-4 acetoxymethyl ester assays respectively. Quercetin pretreatment (20 mg/kg i.p.; 0.5 h before trauma) significantly improved posttraumatic cardiomyocyte apoptosis and cardiac dysfunction. Pretreatment with quercetin (20 μM; 24 h before trauma plasma addition) significantly attenuated trauma-induced viability decreases, TNF-α increases, ROS overproduction and [Ca2+]i overload in H9c2 cells. In conclusion, quercetin may reverse posttraumatic cardiac dysfunction by reducing cardiomyocyte apoptosis through the suppression of TNF-α increases, ROS overproduction and Ca2+ overload in cardiomyocytes, representing a potential preventive approach for the treatment of secondary cardiac injury after mechanical trauma. PMID:27470932

  3. Mechanisms of Neuroprotection by Quercetin: Counteracting Oxidative Stress and More

    PubMed Central

    Costa, Lucio G.; Garrick, Jacqueline M.; Roquè, Pamela J.; Pellacani, Claudia

    2016-01-01

    Increasing interest has recently focused on determining whether several natural compounds, collectively referred to as nutraceuticals, may exert neuroprotective actions in the developing, adult, and aging nervous system. Quercetin, a polyphenol widely present in nature, has received the most attention in this regard. Several studies in vitro, in experimental animals and in humans, have provided supportive evidence for neuroprotective effects of quercetin, either against neurotoxic chemicals or in various models of neuronal injury and neurodegenerative diseases. The exact mechanisms of such protective effects remain elusive, though many hypotheses have been formulated. In addition to a possible direct antioxidant effect, quercetin may also act by stimulating cellular defenses against oxidative stress. Two such pathways include the induction of Nrf2-ARE and induction of the antioxidant/anti-inflammatory enzyme paraoxonase 2 (PON2). In addition, quercetin has been shown to activate sirtuins (SIRT1), to induce autophagy, and to act as a phytoestrogen, all mechanisms by which quercetin may provide its neuroprotection. PMID:26904161

  4. Protective Effect of Quercetin on Posttraumatic Cardiac Injury.

    PubMed

    Jing, Zehao; Wang, Zhuorun; Li, Xiujie; Li, Xintao; Cao, Tingting; Bi, Yue; Zhou, Jicheng; Chen, Xu; Yu, Deqin; Zhu, Liang; Li, Shuzhuang

    2016-01-01

    Quercetin is an important dietary flavonoid present in fruits and vegetables and has attracted attention because of its anti-inflammatory and anti-oxidative properties. Inflammation and oxidative stress play important roles in posttraumatic cardiomyocyte apoptosis, which contributes to secondary cardiac dysfunction. This study investigates the protective effect of quercetin on trauma-induced secondary cardiac injury and the mechanisms involved. Widely accepted nonlethal mechanical trauma models were established. In vivo, cardiomyocyte apoptosis and cardiac dysfunction in rats were assessed using TUNEL staining and a biological mechanic experiment system. In vitro, cell viability, tumour necrosis factor-α (TNF-α), reactive oxygen species (ROS) and [Ca(2+)]i of H9c2 cells were detected using an MTT assay, ELISA, and 2',7'-dichlorofluorescin diacetate and fluo-4 acetoxymethyl ester assays respectively. Quercetin pretreatment (20 mg/kg i.p.; 0.5 h before trauma) significantly improved posttraumatic cardiomyocyte apoptosis and cardiac dysfunction. Pretreatment with quercetin (20 μM; 24 h before trauma plasma addition) significantly attenuated trauma-induced viability decreases, TNF-α increases, ROS overproduction and [Ca(2+)]i overload in H9c2 cells. In conclusion, quercetin may reverse posttraumatic cardiac dysfunction by reducing cardiomyocyte apoptosis through the suppression of TNF-α increases, ROS overproduction and Ca(2+) overload in cardiomyocytes, representing a potential preventive approach for the treatment of secondary cardiac injury after mechanical trauma. PMID:27470932

  5. Quercetin and Its Anti-Allergic Immune Response.

    PubMed

    Mlcek, Jiri; Jurikova, Tunde; Skrovankova, Sona; Sochor, Jiri

    2016-01-01

    Quercetin is the great representative of polyphenols, flavonoids subgroup, flavonols. Its main natural sources in foods are vegetables such as onions, the most studied quercetin containing foods, and broccoli; fruits (apples, berry crops, and grapes); some herbs; tea; and wine. Quercetin is known for its antioxidant activity in radical scavenging and anti-allergic properties characterized by stimulation of immune system, antiviral activity, inhibition of histamine release, decrease in pro-inflammatory cytokines, leukotrienes creation, and suppresses interleukin IL-4 production. It can improve the Th1/Th2 balance, and restrain antigen-specific IgE antibody formation. It is also effective in the inhibition of enzymes such as lipoxygenase, eosinophil and peroxidase and the suppression of inflammatory mediators. All mentioned mechanisms of action contribute to the anti-inflammatory and immunomodulating properties of quercetin that can be effectively utilized in treatment of late-phase, and late-late-phase bronchial asthma responses, allergic rhinitis and restricted peanut-induced anaphylactic reactions. Plant extract of quercetin is the main ingredient of many potential anti-allergic drugs, supplements and enriched products, which is more competent in inhibiting of IL-8 than cromolyn (anti-allergic drug disodium cromoglycate) and suppresses IL-6 and cytosolic calcium level increase. PMID:27187333

  6. Cell-Specific Cre Strains For Genetic Manipulation in Salivary Glands

    PubMed Central

    Maruyama, Eri O.; Aure, Marit H.; Xie, Xiaoling; Myal, Yvonne; Gan, Lin; Ovitt, Catherine E.

    2016-01-01

    The secretory acinar cells of the salivary gland are essential for saliva secretion, but are also the cell type preferentially lost following radiation treatment for head and neck cancer. The source of replacement acinar cells is currently a matter of debate. There is evidence for the presence of adult stem cells located within specific ductal regions of the salivary glands, but our laboratory recently demonstrated that differentiated acinar cells are maintained without significant stem cell contribution. To enable further investigation of salivary gland cell lineages and their origins, we generated three cell-specific Cre driver mouse strains. For genetic manipulation in acinar cells, an inducible Cre recombinase (Cre-ER) was targeted to the prolactin-induced protein (Pip) gene locus. Targeting of the Dcpp1 gene, encoding demilune cell and parotid protein, labels intercalated duct cells, a putative site of salivary gland stem cells, and serous demilune cells of the sublingual gland. Duct cell-specific Cre expression was attempted by targeting the inducible Cre to the Tcfcp2l1 gene locus. Using the R26Tomato Red reporter mouse, we demonstrate that these strains direct inducible, cell-specific expression. Genetic tracing of acinar cells using PipGCE supports the recent finding that differentiated acinar cells clonally expand. Moreover, tracing of intercalated duct cells expressing DcppGCE confirms evidence of duct cell proliferation, but further analysis is required to establish that renewal of secretory acinar cells is dependent on stem cells within these ducts. PMID:26751783

  7. Chromatin states modify network motifs contributing to cell-specific functions

    PubMed Central

    Zhao, Hongying; Liu, Tingting; Liu, Ling; Zhang, Guanxiong; Pang, Lin; Yu, Fulong; Fan, Huihui; Ping, Yanyan; Wang, Li; Xu, Chaohan; Xiao, Yun; Li, Xia

    2015-01-01

    Epigenetic modification can affect many important biological processes, such as cell proliferation and apoptosis. It can alter chromatin conformation and contribute to gene regulation. To investigate how chromatin states associated with network motifs, we assembled chromatin state-modified regulatory networks by combining 269 ChIP-seq data and chromatin states in four cell types. We found that many chromatin states were significantly associated with network motifs, especially for feedforward loops (FFLs). These distinct chromatin state compositions contribute to different expression levels and translational control of targets in FFLs. Strikingly, the chromatin state-modified FFLs were highly cell-specific and, to a large extent, determined cell-selective functions, such as the embryonic stem cell-specific bivalent modification-related FFL with an important role in poising developmentally important genes for expression. Besides, comparisons of chromatin state-modified FFLs between cancerous/stem and primary cell lines revealed specific type of chromatin state alterations that may act together with motif structural changes cooperatively contribute to cell-to-cell functional differences. Combination of these alterations could be helpful in prioritizing candidate genes. Together, this work highlights that a dynamic epigenetic dimension can help network motifs to control cell-specific functions. PMID:26169043

  8. Pharmacokinetics of quercetin-loaded nanodroplets with ultrasound activation and their use for bioimaging

    PubMed Central

    Chang, Li-Wen; Hou, Mei-Ling; Hung, Shuo-Hui; Lin, Lie-Chwen; Tsai, Tung-Hu

    2015-01-01

    Bubble formulations have both diagnostic and therapeutic applications. However, research on nanobubbles/nanodroplets remains in the initial stages. In this study, a nanodroplet formulation was prepared and loaded with a novel class of chemotherapeutic drug, ie, quercetin, to observe its pharmacokinetic properties and ultrasonic bioimaging of specific sites, namely the abdominal vein and bladder. Four parallel groups were designed to investigate the effects of ultrasound and nanodroplets on the pharmacokinetics of quercetin. These groups were quercetin alone, quercetin triggered with ultrasound, quercetin-encapsulated in nanodroplets, and quercetin encapsulated in nanodroplets triggered with ultrasound. Spherical vesicles with a mean diameter of 280 nm were formed, and quercetin was completely encapsulated within. In vivo ultrasonic imaging confirmed that the nanodroplets could be treated by ultrasound. The results indicate that the initial 5-minute serum concentration, area under the concentration–time curve, elimination half-life, and clearance of quercetin were significantly enhanced by nanodroplets with or without ultrasound. PMID:25945049

  9. Pharmacokinetics of quercetin-loaded nanodroplets with ultrasound activation and their use for bioimaging.

    PubMed

    Chang, Li-Wen; Hou, Mei-Ling; Hung, Shuo-Hui; Lin, Lie-Chwen; Tsai, Tung-Hu

    2015-01-01

    Bubble formulations have both diagnostic and therapeutic applications. However, research on nanobubbles/nanodroplets remains in the initial stages. In this study, a nanodroplet formulation was prepared and loaded with a novel class of chemotherapeutic drug, ie, quercetin, to observe its pharmacokinetic properties and ultrasonic bioimaging of specific sites, namely the abdominal vein and bladder. Four parallel groups were designed to investigate the effects of ultrasound and nanodroplets on the pharmacokinetics of quercetin. These groups were quercetin alone, quercetin triggered with ultrasound, quercetin-encapsulated in nanodroplets, and quercetin encapsulated in nanodroplets triggered with ultrasound. Spherical vesicles with a mean diameter of 280 nm were formed, and quercetin was completely encapsulated within. In vivo ultrasonic imaging confirmed that the nanodroplets could be treated by ultrasound. The results indicate that the initial 5-minute serum concentration, area under the concentration-time curve, elimination half-life, and clearance of quercetin were significantly enhanced by nanodroplets with or without ultrasound. PMID:25945049

  10. Formulation, characterization, and evaluation of ligand-conjugated biodegradable quercetin nanoparticles for active targeting.

    PubMed

    Gupta, Anshita; Kaur, Chanchal Deep; Saraf, Shailendra; Saraf, Swarnlata

    2016-05-01

    The aim of this study was to design a targeted drug delivery system carrying a natural anticancer drug Quercetin (Qu), specifically for skin cancer. A central composite design was applied separately for each ligand, and the quadratic model was used for the process. The surface morphology was confirmed by transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR), and in vitro release studies were also performed. The MTT assay was performed against two different cell lines, to measure their anticancer potentials and their targeting ability. The study thus reveals that MA-Qu-PLGA and FA-Qu-PLGA nanoparticles (NPs) can be used as effective drug delivery systems for skin cancer treatment encompassing natural drugs. PMID:25813566

  11. Quercetin as natural stabilizing agent for bio-polymer

    NASA Astrophysics Data System (ADS)

    Morici, Elisabetta; Arrigo, Rossella; Dintcheva, Nadka Tzankova

    2014-05-01

    The introduction of antioxidants in polymers is the main way to prevent or delay the degradation process. In particular natural antioxidants receive attention in the food industry also because of their presumed safety. In this work bio-polymers, i.e. a commercial starch-based polymer (Mater-Bi®) and a bio-polyester (PLA), and a bio-polyether (PEO) were additivated with quercetin, a natural flavonoid antioxidants, in order to formulate bio-based films for ecosustainable packaging and outdoor applications. The photo-oxidation behavior of unstabilized and quercetin stabilized films was analyzed and compared with the behavior of films additivated with a commercial synthetic light stabilizer. The quercetin is able to slow down the photo-degradation rate of all bio-polymeric films investigated in similar way to the synthetic stabilizer.

  12. Quercetin as natural stabilizing agent for bio-polymer

    SciTech Connect

    Morici, Elisabetta; Arrigo, Rossella; Dintcheva, Nadka Tzankova

    2014-05-15

    The introduction of antioxidants in polymers is the main way to prevent or delay the degradation process. In particular natural antioxidants receive attention in the food industry also because of their presumed safety. In this work bio-polymers, i.e. a commercial starch-based polymer (Mater-Bi®) and a bio-polyester (PLA), and a bio-polyether (PEO) were additivated with quercetin, a natural flavonoid antioxidants, in order to formulate bio-based films for ecosustainable packaging and outdoor applications. The photo-oxidation behavior of unstabilized and quercetin stabilized films was analyzed and compared with the behavior of films additivated with a commercial synthetic light stabilizer. The quercetin is able to slow down the photo-degradation rate of all bio-polymeric films investigated in similar way to the synthetic stabilizer.

  13. [Hypoglycemic and hypolipidemic effects of quercetin and its glycosides].

    PubMed

    Yan, Shu-xia; Li, Xian; Sun, Chong-de; Chen, Kun-song

    2015-12-01

    Quercetin and its glycosides are important flavonols in traditional herbal drugs and plant-derived food, and they have diverse hiological activities such as antioxidant, anticarcinogenic, anti-inflammatory, hypoglycemic and hypolipidemic activities. Numerous studies have demonstrated that quercetin and its glycosides were effective in the prevention and treatment of non-infectious chronic disease such as diabetes, obesity, and hyperlipidemia. They can regulate glucose and lipid metaholism through different mechanisms. They can decrease blood glucose via protecting pancreatic/p cells or/and improving insulin sensitivity. Also, they have lipid-lowering effects, which may be the result of regulation of lipid catabolism or/and anabolism. Their distributions, as well as the hypoglycemic and hypolipidemic effects are reviewed in this paper. In addition, further bioactivities as well as their dose-activity relationship, structure-activity relationship, bioavailability, and future clinical application of quercetin and its glycosides are discussed and proposed. PMID:27141664

  14. Enzymatic modification of chitosan with quercetin and its application as antioxidant edible films.

    PubMed

    Torres, E; Marín, V; Aburto, J; Beltrán, H I; Shirai, K; Villanueva, S; Sandoval, G

    2012-01-01

    Quercetin, rutin, naringin, hesperidin and chrysin were tested as substrates for chloroperoxidase to produce reactive quinones to graft onto chitosan. Quercetin and rutin quinones were successfully chemically attached to low molecular weight chitosan. The quercetin-modified chitosan showed an enhancement of plastic, antioxidant and antimicrobial properties as well as of thermal degradability. Finally, chitosan-quercetin films visibly decreased enzymatic oxidation when applied to Opuntia ficus indica cladodes. PMID:22586910

  15. Preparation Of Gold Nanoparticle-Quercetin Complexes By Citrate Reduction Method

    NASA Astrophysics Data System (ADS)

    Pal, Rajat; Chakraborti, Abhay Sankar

    2010-10-01

    Quercetin is an important flavonoid and possesses strong antioxidant property. The aim of the present study is to formulate and characterize quercetin coated gold nanoparticles. Quercetin was conjugated with gold nanoparticle during synthesis of the particle by citrate reduction of chloroauric acid. The conjugates were characterized by different techniques like Atomic Force Microscopy, Dynamic Light Scattering, Transmission Electron Microscopy, Absorption Spectroscopy, Differential Scanning Calorimetry and Thermal Gravimetric Analysis. All these studies suggest formation of stable quercetin-gold nanoparticle complex.

  16. Quercetin Targets Cysteine String Protein (CSPα) and Impairs Synaptic Transmission

    PubMed Central

    Xu, Fenglian; Proft, Juliane; Gibbs, Sarah; Winkfein, Bob; Johnson, Jadah N.; Syed, Naweed; Braun, Janice E. A.

    2010-01-01

    Background Cysteine string protein (CSPα) is a synaptic vesicle protein that displays unique anti-neurodegenerative properties. CSPα is a member of the conserved J protein family, also called the Hsp40 (heat shock protein of 40 kDa) protein family, whose importance in protein folding has been recognized for many years. Deletion of the CSPα in mice results in knockout mice that are normal for the first 2–3 weeks of life followed by an unexplained presynaptic neurodegeneration and premature death. How CSPα prevents neurodegeneration is currently not known. As a neuroprotective synaptic vesicle protein, CSPα represents a promising therapeutic target for the prevention of neurodegenerative disorders. Methodology/Principal Findings Here, we demonstrate that the flavonoid quercetin promotes formation of stable CSPα-CSPα dimers and that quercetin-induced dimerization is dependent on the unique cysteine string region. Furthermore, in primary cultures of Lymnaea neurons, quercetin induction of CSPα dimers correlates with an inhibition of synapse formation and synaptic transmission suggesting that quercetin interfers with CSPα function. Quercetin's action on CSPα is concentration dependent and does not promote dimerization of other synaptic proteins or other J protein family members and reduces the assembly of CSPα:Hsc70 units (70kDa heat shock cognate protein). Conclusions/Significance Quercetin is a plant derived flavonoid and popular nutritional supplement proposed to prevent memory loss and altitude sickness among other ailments, although its precise mechanism(s) of action has been unclear. In view of the therapeutic promise of upregulation of CSPα and the undesired consequences of CSPα dysfunction, our data establish an essential proof of principle that pharmaceutical agents can selectively target the neuroprotective J protein CSPα. PMID:20548785

  17. Comparison of methods for rapid analysis of quercetin.

    PubMed

    Pardo-Barrela, Jessica; Lago-Crespo, Miguel; Lage-Yusty, María Asunción; López-Hernández, Julia

    2015-03-01

    Quercetin is a polyphenol of growing interest that is present in many foods. In this study, we compared two methods for its determination in samples of drinks made of juice and in dietary supplements, one chromatographic (HPLC) and other spectrofluorimetric (constant-wavelength synchronous spectrofluorimetry). To confirm the identification of the quercetin in the samples an HPLC-PDA-MS/MS system was used. It was concluded that both methods are suitable for dietary supplements and the choice of one or the other depends on the type of sample, time available for the analysis as well as the available resources. For juice beverages only HPLC is suitable. PMID:25488586

  18. Production of 3-O-xylosyl quercetin in Escherichia coli.

    PubMed

    Pandey, Ramesh Prasad; Malla, Sailesh; Simkhada, Dinesh; Kim, Byung-Gee; Sohng, Jae Kyung

    2013-03-01

    Quercetin, a flavonol aglycone, is one of the most abundant flavonoids with high medicinal value. The bioavailability and pharmacokinetic properties of quercetin are influenced by the type of sugars attached to the molecule. To efficiently diversify the therapeutic uses of quercetin, Escherichia coli was harnessed as a production factory by the installation of various plant and bacterial UDP-xylose sugar biosynthetic genes. The genes encoding for the UDP-xylose pathway enzymes phosphoglucomutase (nfa44530), glucose-1-phosphate uridylyltransferase (galU), UDP-glucose dehydrogenase (calS8), and UDP-glucuronic acid decarboxylase (calS9) were overexpressed in E. coli BL21 (DE3) along with a glycosyltransferase (arGt-3) from Arabidopsis thaliana. Furthermore, E. coli BL21(DE3)/∆pgi, E. coli BL21(DE3)/∆zwf, E. coli BL21(DE3)/∆pgi∆zwf, and E. coli BL21(DE3)/∆pgi∆zwf∆ushA mutants carrying the aforementioned UDP-xylose sugar biosynthetic genes and glycosyltransferase and the galU-integrated E. coli BL21(DE3)/∆pgi host harboring only calS8, calS9, and arGt-3 were constructed to enhance whole-cell bioconversion of exogeneously supplied quercetin into 3-O-xylosyl quercetin. Here, we report the highest production of 3-O-xylosyl quercetin with E. coli BL21 (DE3)/∆pgi∆zwf∆ushA carrying UDP-xylose sugar biosynthetic genes and glycosyltransferase. The maximum concentration of 3-O-xylosyl quercetin achieved was 23.78 mg/L (54.75 μM), representing 54.75 % bioconversion, which was an ~4.8-fold higher bioconversion than that shown by E. coli BL21 (DE3) with the same set of genes when the reaction was carried out in 5-mL culture tubes with 100 μM quercetin under optimized conditions. Bioconversion was further improved by 98 % when the reaction was scaled up in a 3-L fermentor at 36 h. PMID:23053089

  19. Estimated Daily Intake and Seasonal Food Sources of Quercetin in Japan

    PubMed Central

    Nishimuro, Haruno; Ohnishi, Hirofumi; Sato, Midori; Ohnishi-Kameyama, Mayumi; Matsunaga, Izumi; Naito, Shigehiro; Ippoushi, Katsunari; Oike, Hideaki; Nagata, Tadahiro; Akasaka, Hiroshi; Saitoh, Shigeyuki; Shimamoto, Kazuaki; Kobori, Masuko

    2015-01-01

    Quercetin is a promising food component, which can prevent lifestyle related diseases. To understand the dietary intake of quercetin in the subjects of a population-based cohort study and in the Japanese population, we first determined the quercetin content in foods available in the market during June and July in or near a town in Hokkaido, Japan. Red leaf lettuce, asparagus, and onions contained high amounts of quercetin derivatives. We then estimated the daily quercetin intake by 570 residents aged 20–92 years old in the town using a food frequency questionnaire (FFQ). The average and median quercetin intakes were 16.2 and 15.5 mg day−1, respectively. The quercetin intakes by men were lower than those by women; the quercetin intakes showed a low correlation with age in both men and women. The estimated quercetin intake was similar during summer and winter. Quercetin was mainly ingested from onions and green tea, both in summer and in winter. Vegetables, such as asparagus, green pepper, tomatoes, and red leaf lettuce, were good sources of quercetin in summer. Our results will help to elucidate the association between quercetin intake and risks of lifestyle-related diseases by further prospective cohort study and establish healthy dietary requirements with the consumption of more physiologically useful components from foods. PMID:25849945

  20. Quercetin Increases Hepatic Homocysteine Remethylation and Transsulfuration in Rats Fed a Methionine-Enriched Diet

    PubMed Central

    Meng, Bin; Gao, Weina; Wei, Jingyu; Pu, Lingling; Tang, Zhenchuang; Guo, Changjiang

    2015-01-01

    This study was aimed at investigating the effects of quercetin on mRNA expression and activity of critical enzymes in homocysteine metabolism in rats fed a methionine-enriched diet. Rats were fed for 6 weeks the following diets, that is, control, 0.5% quercetin, 1.0% methionine, and 1.0% methionine plus 0.5% quercetin diets. Serum homocysteine was significantly increased after methionine treatment and decreased after the addition of quercetin. The mRNA expression of methionine synthase was significantly increased after methionine or methionine plus quercetin supplementation, while its enzymatic activity was significantly increased after methionine plus quercetin supplementation. The mRNA expression and enzymatic activity of cystathionine β-synthase and cystathionine γ-lyase were upregulated after quercetin, methionine, or quercetin plus methionine treatment and a more significant increase was observed for hepatic cystathionine β-synthase in the methionine plus quercetin treated rats, suggesting an interaction between methionine and quercetin. Meanwhile, hepatic ratio of S-adenosylmethionine to S-adenosylhomocysteine was significantly decreased in response to methionine supplementation and normalized after the addition of quercetin. It is concluded that quercetin reduces serum homocysteine by increasing remethylation and transsulfuration of homocysteine in rats exposed to a methionine-enriched diet. PMID:26558284

  1. Estimated daily intake and seasonal food sources of quercetin in Japan.

    PubMed

    Nishimuro, Haruno; Ohnishi, Hirofumi; Sato, Midori; Ohnishi-Kameyama, Mayumi; Matsunaga, Izumi; Naito, Shigehiro; Ippoushi, Katsunari; Oike, Hideaki; Nagata, Tadahiro; Akasaka, Hiroshi; Saitoh, Shigeyuki; Shimamoto, Kazuaki; Kobori, Masuko

    2015-04-01

    Quercetin is a promising food component, which can prevent lifestyle related diseases. To understand the dietary intake of quercetin in the subjects of a population-based cohort study and in the Japanese population, we first determined the quercetin content in foods available in the market during June and July in or near a town in Hokkaido, Japan. Red leaf lettuce, asparagus, and onions contained high amounts of quercetin derivatives. We then estimated the daily quercetin intake by 570 residents aged 20-92 years old in the town using a food frequency questionnaire (FFQ). The average and median quercetin intakes were 16.2 and 15.5 mg day(-1), respectively. The quercetin intakes by men were lower than those by women; the quercetin intakes showed a low correlation with age in both men and women. The estimated quercetin intake was similar during summer and winter. Quercetin was mainly ingested from onions and green tea, both in summer and in winter. Vegetables, such as asparagus, green pepper, tomatoes, and red leaf lettuce, were good sources of quercetin in summer. Our results will help to elucidate the association between quercetin intake and risks of lifestyle-related diseases by further prospective cohort study and establish healthy dietary requirements with the consumption of more physiologically useful components from foods. PMID:25849945

  2. Epigenetic control of cell specification during female gametogenesis.

    PubMed

    Armenta-Medina, Alma; Demesa-Arévalo, Edgar; Vielle-Calzada, Jean-Philippe

    2011-06-01

    In flowering plants, the formation of gametes depends on the differentiation of cellular precursors that divide meiotically before giving rise to a multicellular gametophyte. The establishment of this gametophytic phase presents an opportunity for natural selection to act on the haploid plant genome by means of epigenetic mechanisms that ensure a tight regulation of plant reproductive development. Despite this early acting selective pressure, there are numerous examples of naturally occurring developmental alternatives that suggest a flexible regulatory control of cell specification and subsequent gamete formation in flowering plants. In this review, we discuss recent findings indicating that epigenetic mechanisms related to the activity of small RNA pathways prevailing during ovule formation play an essential role in cell specification and genome integrity. We also compare these findings to small RNA pathways acting during gametogenesis in animals and discuss their implications for the understanding of the mechanisms that control the establishment of the female gametophytic lineage during both sexual reproduction and apomixis. PMID:21484604

  3. Tagging and Enriching Proteins Enables Cell-Specific Proteomics.

    PubMed

    Elliott, Thomas S; Bianco, Ambra; Townsley, Fiona M; Fried, Stephen D; Chin, Jason W

    2016-07-21

    Cell-specific proteomics in multicellular systems and whole animals is a promising approach to understand the differentiated functions of cells and tissues. Here, we extend our stochastic orthogonal recoding of translation (SORT) approach for the co-translational tagging of proteomes with a cyclopropene-containing amino acid in response to diverse codons in genetically targeted cells, and create a tetrazine-biotin probe containing a cleavable linker that offers a way to enrich and identify tagged proteins. We demonstrate that SORT with enrichment, SORT-E, efficiently recovers and enriches SORT tagged proteins and enables specific identification of enriched proteins via mass spectrometry, including low-abundance proteins. We show that tagging at distinct codons enriches overlapping, but distinct sets of proteins, suggesting that tagging at more than one codon enhances proteome coverage. Using SORT-E, we accomplish cell-specific proteomics in the fly. These results suggest that SORT-E will enable the definition of cell-specific proteomes in animals during development, disease progression, and learning and memory. PMID:27447048

  4. Ab initio molecular dynamics of the reaction of quercetin with superoxide radical

    NASA Astrophysics Data System (ADS)

    Lespade, Laure

    2016-08-01

    Superoxide plays an important role in biology but in unregulated concentrations it is implicated in a lot of diseases such as cancer or atherosclerosis. Antioxidants like flavonoids are abundant in plant and are good scavengers of superoxide radical. The modeling of superoxide scavenging by flavonoids from the diet still remains a challenge. In this study, ab initio molecular dynamics of the reaction of the flavonoid quercetin toward superoxide radical has been carried out using Car-Parrinello density functional theory. The study has proven different reactant solvation by modifying the number of water molecules surrounding superoxide. The reaction consists in the gift of a hydrogen atom of one of the hydroxyl groups of quercetin to the radical. When it occurs, it is relatively fast, lower than 100 fs. Calculations show that it depends largely on the environment of the hydroxyl group giving its hydrogen atom, the geometry of the first water layer and the presence of a certain number of water molecules in the second layer, indicating a great influence of the solvent on the reactivity.

  5. Synthesis of fluorescent dye-doped silica nanoparticles for target-cell-specific delivery and intracellular microRNA imaging.

    PubMed

    Li, Henan; Mu, Yawen; Qian, Shanshan; Lu, Jusheng; Wan, Yakun; Fu, Guodong; Liu, Songqin

    2015-01-21

    MicroRNA (miRNA) is found to be up-regulated in many kinds of cancer and therefore is classified as an oncomiR. Herein, we design a multifunctional fluorescent nanoprobe (FSiNP-AS/MB) with the AS1411 aptamer and a molecular beacon (MB) co-immobilized on the surface of the fluorescent dye-doped silica nanoparticles (FSiNPs) for target-cell-specific delivery and intracellular miRNA imaging. The FSiNPs were prepared by a facile reverse microemulsion method from tetraethoxysilane and silane derivatized coumarin that was previously synthesized by click chemistry. The as-prepared FSiNPs possess uniform size distribution, good optical stability and biocompatibility. In addition, there is a remarkable affinity interaction between the AS1411 aptamer and the nucleolin protein on the cancer cell surface. Thus, a target-cell-specific delivery system by the FSiNP-AS/MB is proposed for effectively transferring a MB into the cancer cells to recognize the target miRNA. Using miRNA-21 in MCF-7 cells (a human breast cancer cell line) as a model, the proposed multifunctional nanosystems not only allow target-cell-specific delivery with the binding affinity of AS1411, but also can track simultaneously the transfected cells and detect intracellular miRNA in situ. The proposed multifunctional nanosystems are a promising platform for a highly sensitive luminescent nonviral vector in biomedical and clinical research. PMID:25417796

  6. Ameliorating effect of quercetin on acute pentylenetetrazole induced seizures in rats

    PubMed Central

    Sefil, Fatih; Kahraman, Ibrahim; Dokuyucu, Recep; Gokce, Hasan; Ozturk, Atakan; Tutuk, Okan; Aydin, Mehmet; Ozkan, Umit; Pinar, Neslihan

    2014-01-01

    Objective: The aim of the study to elicit effects of pure quercetin in pentylenetetrazole (PTZ) and picrotoxin induced seizures. Materials and methods: Each animal group was divided into six groups and composed of six rats. Rats were assigned to the following experiments and groups (G): (G1) PTZ 45 mg/kg + DMSO; (G2) PTZ 45 mg/kg + 5 mg/kg quercetin; (G3) PTZ 45 mg/kg + 10 mg/kg quercetin; (G4) PTZ 45 mg/kg + 20 mg/kg quercetin; (G5) PTZ 45 mg/kg + 40 mg/kg quercetin; (G6) Picrotoxin 5 mg/kg + DMSO; (G7) Picrotoxin 5 mg/kg + 10 mg/kg quercetin; (G8) Picrotoxin 5 mg/kg + 20 mg/kg quercetin. In all groups quercetin were injected 30 min before PTZ and picrotoxin applications. Results: Compared to PTZ, quercetin significantly prolonged onset of the seizure in 10 mg/kg (P < 0.05) and reduced the seizure stage in 10 mg/kg quercetin injected group (P < 0.01). Compared to PTZ, quercetin also declined the generalized seizure duration at 10 mg/kg (P < 0.01) and 20 mg/kg (P < 0.05) doses. At the doses of 5 mg/kg and 40 mg/kg quercetin there were no significant changes in seizure parameters. Development of picrotoxin induced seizures is slower than in PTZ. Quercetin was found to be unable to prevent seizure in picrotoxin induced seizures. Surprisingly, quercetin also significantly reduced the onset of seizures at the dose of 20 mg/kg (P < 0.05). Conclusion: quercetin (at doses of 10 and 20 mg/kg i.p) prevented seizures in PTZ (45 mg/kg i.p) induced seizures. Especially, 10 mg/kg PTZ prolonged onset of seizures, reduced the seizure duration and seizure severity score in comparison with control group. At a higher (40 mg/kg) dose quercetin failed to prevent PTZ induced seizures. In addition 20 mg/kg quercetin significantly reduced the onset of seizures that suggest a preconvulsive effect. 20 mg/kg quercetin reduced the onset of picrotoxin induced seizures. In picrotoxin model, it may be claimed that quercetin at higher doses accelerate the epileptic activity owing to its

  7. Quercetin as colorimetric reagent for determination of zirconium

    USGS Publications Warehouse

    Grimaldi, F.S.; White, C.E.

    1953-01-01

    Methods described in the literature for the determination of zirconium are generally designed for relatively large amounts of this element. A good procedure using colorimetric reagent for the determination of trace amounts is desirable. Quercetin has been found to yield a sensitive color reaction with zirconium suitable for the determination of from 0.1 to 50?? of zirconium dioxide. The procedure developed involves the separation of zirconium from interfering elements by precipitation with p-dimethylaminoazophenylarsonic acid prior to its estimation with quercetin. The quercetin reaction is carried out in 0.5N hydrochloric acid solution. Under the operating conditions it is indicated that quercetin forms a 2 to 1 complex with zirconium; however, a 2 to 1 and a 1 to 1 complex can coexist under special conditions. Approximate values for the equilibrium constants of the complexes are K1 = 0.33 ?? 10-5 and K2 = 1.3 ?? 10-9. Seven Bureau of Standards samples of glass sands and refractories were analyzed with excellent results. The method described should find considerable application in the analysis of minerals and other materials for macro as well as micro amounts of zirconium.

  8. DFT study of glycosyl group reactivity in quercetin derivatives

    NASA Astrophysics Data System (ADS)

    Jeevitha, D.; Sadasivam, K.; Praveena, R.; Jayaprakasam, R.

    2016-09-01

    Density functional theory (DFT) is used to compute relevant electronic properties with the purpose of generating precise information which facilitates the best activity given by the positions of glycosyl group attached at all 3 different rings of quercetin such as Q3G (C- ring), Q7G (A-ring) and Q3‧G (B-ring). Computed values of the OH BDE, frontier molecular orbitals (FMOs), molecular electrostatic potential (MEP), Density of states (DOS,PDOS,OPDOS) and electronic properties such as electron affinity (EA), ionization potential (IP), softness (S), hardness (η), electronegativity (χ) and electrophilic index (ω) indicate that the title compounds possess good radical scavenging activity. Charge delocalization and intramolecular hydrogen bonds are characterized using natural bond orbital (NBO) analysis. NBO accurately differentiate the weak and strong intramolecular hydrogen bond of quercetin-O-glycoside compounds. Results available from the computational investigation have proved that A-ring glycoside of quercetin is capable of donating electrons and acts as a good anti-oxidant than B-ring glycoside and C-ring glycoside of quercetin.

  9. PI-103 and Quercetin Attenuate PI3K-AKT Signaling Pathway in T- Cell Lymphoma Exposed to Hydrogen Peroxide

    PubMed Central

    Maurya, Akhilendra Kumar; Vinayak, Manjula

    2016-01-01

    Phosphatidylinositol 3 kinase—protein kinase B (PI3K-AKT) pathway has been considered as major drug target site due to its frequent activation in cancer. AKT regulates the activity of various targets to promote tumorigenesis and metastasis. Accumulation of reactive oxygen species (ROS) has been linked to oxidative stress and regulation of signaling pathways for metabolic adaptation of tumor microenvironment. Hydrogen peroxide (H2O2) in this context is used as ROS source for oxidative stress preconditioning. Antioxidants are commonly considered to be beneficial to reduce detrimental effects of ROS and are recommended as dietary supplements. Quercetin, a ubiquitous bioactive flavonoid is a dietary component which has attracted much of interest due to its potential health-promoting effects. Present study is aimed to analyze PI3K-AKT signaling pathway in H2O2 exposed Dalton’s lymphoma ascite (DLA) cells. Further, regulation of PI3K-AKT pathway by quercetin as well as PI-103, an inhibitor of PI3K was analyzed. Exposure of H2O2 (1mM H2O2 for 30min) to DLA cells caused ROS accumulation and resulted in increased phosphorylation of PI3K and downstream proteins PDK1 and AKT (Ser-473 and Thr-308), cell survival factors BAD and ERK1/2, as well as TNFR1. However, level of tumor suppressor PTEN was declined. Both PI-103 & quercetin suppressed the enhanced level of ROS and significantly down-regulated phosphorylation of AKT, PDK1, BAD and level of TNFR1 as well as increased the level of PTEN in H2O2 induced lymphoma cells. The overall result suggests that quercetin and PI3K inhibitor PI-103 attenuate PI3K-AKT pathway in a similar mechanism. PMID:27494022

  10. Effect of quercetin and its metabolites isorhamnetin and quercetin-3-glucuronide on inflammatory gene expression: role of miR-155.

    PubMed

    Boesch-Saadatmandi, Christine; Loboda, Agnieszka; Wagner, Anika E; Stachurska, Anna; Jozkowicz, Alicja; Dulak, Jozef; Döring, Frank; Wolffram, Siegfried; Rimbach, Gerald

    2011-03-01

    In the present study the effect of quercetin and its major metabolites quercetin-3-glucuronide (Q3G) and isorhamnetin on inflammatory gene expression was determined in murine RAW264.7 macrophages stimulated with lipopolysaccharide. Quercetin and isorhamnetin but not Q3G significantly decreased mRNA and protein levels of tumor necrosis factor alpha. Furthermore a significant decrease in mRNA levels of interleukin 1β, interleukin 6, macrophage inflammatory protein 1α and inducible nitric oxide synthase was evident in response to the quercetin treatment. However Q3G did not affect inflammatory gene expression. Anti-inflammatory properties of quercetin and isorhamnetin were accompanied by an increase in heme oxygenase 1 protein levels, a downstream target of the transcription factor Nrf2, known to antagonize chronic inflammation. Furthermore, proinflammatory microRNA-155 was down-regulated by quercetin and isorhamnetin but not by Q3G. Finally, anti-inflammatory properties of quercetin were confirmed in vivo in mice fed quercetin-enriched diets (0.1 mg quercetin/g diet) over 6 weeks. PMID:20579867

  11. A Potent Inhibitor of Phosphoinositide 3-Kinase (PI3K) and Mitogen Activated Protein (MAP) Kinase Signalling, Quercetin (3, 3', 4', 5, 7-Pentahydroxyflavone) Promotes Cell Death in Ultraviolet (UV)-B-Irradiated B16F10 Melanoma Cells

    PubMed Central

    Rafiq, Rather A.; Quadri, Afnan; Nazir, Lone A.; Peerzada, Kaiser; Ganai, Bashir A.; Tasduq, Sheikh A.

    2015-01-01

    Ultraviolet (UV) radiation–induced skin damage contributes strongly to the formation of melanoma, a highly lethal form of skin cancer. Quercetin (Qu), the most widely consumed dietary bioflavonoid and well known inhibitor of phosphoinositide 3-kinase (PI3K) and mitogen activated protein (MAP) kinase signalling, has been reported to be chemopreventive in several forms of non-melanoma skin cancers. Here, we report that the treatment of ultraviolet (UV)-B-irradiated B16F10 melanoma cells with quercetin resulted in a dose dependent reduction in cell viability and increased apoptosis. The present study has brought out that the pro-apoptotic effects of quercetin in UVB-irradiated B16F10 cells are mediated through the elevation of intracellular reactive oxygen species (ROS) formation, calcium homeostasis imbalance, modulation of anti-oxidant defence response and depolarization of mitochondrial membrane potential (ΔΨM). Promotion of UVB-induced cell death by quercetin was further revealed by cleavage of chromosomal DNA, caspase activation, poly (ADP) ribose polymerase (PARP) cleavage, and an increase in sub-G1 cells. Quercetin markedly attenuated MEK-ERK signalling, influenced PI3K/Akt pathway, and potentially enhanced the UVB-induced NF-κB nuclear translocation. Furthermore, combined UVB and quercetin treatment decreased the ratio of Bcl-2 to that of Bax, and upregulated the expression of Bim and apoptosis inducing factor (AIF). Overall, these results suggest the possibility of using quercetin in combination with UVB as a possible treatment option for melanoma in future. PMID:26148186

  12. A Potent Inhibitor of Phosphoinositide 3-Kinase (PI3K) and Mitogen Activated Protein (MAP) Kinase Signalling, Quercetin (3, 3', 4', 5, 7-Pentahydroxyflavone) Promotes Cell Death in Ultraviolet (UV)-B-Irradiated B16F10 Melanoma Cells.

    PubMed

    Rafiq, Rather A; Quadri, Afnan; Nazir, Lone A; Peerzada, Kaiser; Ganai, Bashir A; Tasduq, Sheikh A

    2015-01-01

    Ultraviolet (UV) radiation-induced skin damage contributes strongly to the formation of melanoma, a highly lethal form of skin cancer. Quercetin (Qu), the most widely consumed dietary bioflavonoid and well known inhibitor of phosphoinositide 3-kinase (PI3K) and mitogen activated protein (MAP) kinase signalling, has been reported to be chemopreventive in several forms of non-melanoma skin cancers. Here, we report that the treatment of ultraviolet (UV)-B-irradiated B16F10 melanoma cells with quercetin resulted in a dose dependent reduction in cell viability and increased apoptosis. The present study has brought out that the pro-apoptotic effects of quercetin in UVB-irradiated B16F10 cells are mediated through the elevation of intracellular reactive oxygen species (ROS) formation, calcium homeostasis imbalance, modulation of anti-oxidant defence response and depolarization of mitochondrial membrane potential (ΔΨM). Promotion of UVB-induced cell death by quercetin was further revealed by cleavage of chromosomal DNA, caspase activation, poly (ADP) ribose polymerase (PARP) cleavage, and an increase in sub-G1 cells. Quercetin markedly attenuated MEK-ERK signalling, influenced PI3K/Akt pathway, and potentially enhanced the UVB-induced NF-κB nuclear translocation. Furthermore, combined UVB and quercetin treatment decreased the ratio of Bcl-2 to that of Bax, and upregulated the expression of Bim and apoptosis inducing factor (AIF). Overall, these results suggest the possibility of using quercetin in combination with UVB as a possible treatment option for melanoma in future. PMID:26148186

  13. Characterization of adsorption and electronic excited states of quercetin on titanium dioxide nanoparticles

    NASA Astrophysics Data System (ADS)

    Zdyb, Agata; Krawczyk, Stanisław

    2016-03-01

    Adsorption of quercetin on colloidal titanium dioxide nanoparticles in ethanol and its excited-state electronic structure were investigated by means of electronic and vibrational spectroscopies. The changes in electronic charge redistribution as reflected by the dipole moment difference, ∆μ, between the ground and excited electronic states were measured with electroabsorption spectroscopy and analyzed using results of TD DFT computations. Adsorption of quercetin causes a red shift of its absorption spectrum. Raman spectra of quercetin analyzed with reference to analogous data for morin indicate binding of quercetin through the hydroxy groups of the catechol moiety. The difference dipole moment, which is 5.5 D in free quercetin, increases to 11.8 D in opposite direction in adsorbed quercetin, and is associated with charge-transfer to the Ti atom. The computed transition energy, intensity, vector Δμ and molecular orbitals involved in the electronic transition at different molecular configurations indicate a bidentate chelating mode of binding of quercetin.

  14. Potential cell-specific functions of CXCR4 in atherosclerosis.

    PubMed

    Weber, Christian; Döring, Yvonne; Noels, Heidi

    2016-05-10

    The chemokine CXCL12 and its receptor CXCR4 form an important axis contributing to cellular functions in homeostasis and disease. In addition, the atypical CXCL12 receptor CXCR7 may shape the availability and function of CXCL12. Further to their role through progenitor cell mobilization, CXCL12 and CXCR4 may affect native atherogenesis by modifying atherosclerosis-relevant cellular functions. This short review intends to provide a concise summary of current knowledge with regards to cell-specific functions of CXCL12 and its receptors CXCR4 and CXCR7 with potential implications for the initiation and progression of atherosclerosis. PMID:25586789

  15. Birthdating studies reshape models for pituitary gland cell specification.

    PubMed

    Davis, Shannon W; Mortensen, Amanda H; Camper, Sally A

    2011-04-15

    The intermediate and anterior lobes of the pituitary gland are derived from an invagination of oral ectoderm that forms Rathke's pouch. During gestation proliferating cells are enriched around the pouch lumen, and they appear to delaminate as they exit the cell cycle and differentiate. During late mouse gestation and the postnatal period, anterior lobe progenitors re-enter the cell cycle and expand the populations of specialized, hormone-producing cells. At birth, all cell types are present, and their localization appears stratified based on cell type. We conducted a birth dating study of Rathke's pouch derivatives to determine whether the location of specialized cells at birth is correlated with the timing of cell cycle exit. We find that all of the anterior lobe cell types initiate differentiation concurrently with a peak between e11.5 and e13.5. Differentiation of intermediate lobe melanotropes is delayed relative to anterior lobe cell types. We discovered that specialized cell types are not grouped together based on birth date and are dispersed throughout the anterior lobe. Thus, the apparent stratification of specialized cells at birth is not correlated with cell cycle exit. Thus, the currently popular model of cell specification, dependent upon timing of extrinsic, directional gradients of signaling molecules, needs revision. We propose that signals intrinsic to Rathke's pouch are necessary for cell specification between e11.5 and e13.5 and that cell-cell communication likely plays an important role in regulating this process. PMID:21262217

  16. Cell-specific translational profiling in acute kidney injury

    PubMed Central

    Liu, Jing; Krautzberger, A. Michaela; Sui, Shannan H.; Hofmann, Oliver M.; Chen, Ying; Baetscher, Manfred; Grgic, Ivica; Kumar, Sanjeev; Humphreys, Benjamin; Hide, Winston A.; McMahon, Andrew P.

    2014-01-01

    Acute kidney injury (AKI) promotes an abrupt loss of kidney function that results in substantial morbidity and mortality. Considerable effort has gone toward identification of diagnostic biomarkers and analysis of AKI-associated molecular events; however, most studies have adopted organ-wide approaches and have not elucidated the interplay among different cell types involved in AKI pathophysiology. To better characterize AKI-associated molecular and cellular events, we developed a mouse line that enables the identification of translational profiles in specific cell types. This strategy relies on CRE recombinase–dependent activation of an EGFP-tagged L10a ribosomal protein subunit, which allows translating ribosome affinity purification (TRAP) of mRNA populations in CRE-expressing cells. Combining this mouse line with cell type–specific CRE-driver lines, we identified distinct cellular responses in an ischemia reperfusion injury (IRI) model of AKI. Twenty-four hours following IRI, distinct translational signatures were identified in the nephron, kidney interstitial cell populations, vascular endothelium, and macrophages/monocytes. Furthermore, TRAP captured known IRI-associated markers, validating this approach. Biological function annotation, canonical pathway analysis, and in situ analysis of identified response genes provided insight into cell-specific injury signatures. Our study provides a deep, cell-based view of early injury-associated molecular events in AKI and documents a versatile, genetic tool to monitor cell-specific and temporal-specific biological processes in disease modeling. PMID:24569379

  17. Evaluation of tolerable levels of dietary quercetin for exerting its antioxidative effect in high cholesterol-fed rats.

    PubMed

    Azuma, Keiko; Ippoushi, Katsunari; Terao, Junji

    2010-04-01

    The tolerable level of dietary quercetin for exerting its antioxidative effect was evaluated in high cholesterol-fed rats, using quercetin-containing diets (31-1260 mg quercetin/kg body weight/day) and onion diets (19-94 mg quercetin aglycone equivalent/kg body weight/day), from the viewpoint of a safety assessment. After feeding for 4 weeks, the urinary 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) levels of the quercetin-containing diet groups fed more than 157 mg quercetin/kg body weight/day were higher than the group fed a quercetin-free diet, although the plasma quercetin metabolite levels and plasma antioxidative activity were elevated depending on the amounts of quercetin or onion diet intake. No significant effect on body weight gain by quercetin-containing diets or onion diets was observed. However, ratios of the liver and kidney weights to the body weight were significantly increased in the quercetin-containing diet groups fed more than 314 mg and 157 mg quercetin/kg body weight/day, respectively, and in the onion diet groups fed more than 47 mg quercetin aglycone equivalent/kg body weight/day. These results indicated that the tolerable level for dietary quercetin for exerting its antioxidative effect was between 126 and 157 mg/kg/day for the quercetin diet and between 19 and 34 mg/kg/day for the onion diet. PMID:20138950

  18. Quercetin represses apolipoprotein B expression by inhibiting the transcriptional activity of C/EBPβ.

    PubMed

    Shimizu, Makoto; Li, Juan; Inoue, Jun; Sato, Ryuichiro

    2015-01-01

    Quercetin is one of the most abundant polyphenolic flavonoids found in fruits and vegetables and has anti-oxidative and anti-obesity effects. Because the small intestine is a major absorptive organ of dietary nutrients, it is likely that highly concentrated food constituents, including polyphenols, are present in the small intestinal epithelial cells, suggesting that food factors may have a profound effect in this tissue. To identify novel targets of quercetin in the intestinal enterocytes, mRNA profiling using human intestinal epithelial Caco-2 cells was performed. We found that mRNA levels of some apolipoproteins, particularly apolipoprotein B (apoB), are downregulated in the presence of quercetin. On the exposure of Caco-2 cells to quercetin, both mRNA and protein levels of apoB were decreased. Promoter analysis of the human apoB revealed that quercetin response element is localized at the 5'-proximal promoter region, which contains a conserved CCAAT enhancer-binding protein (C/EBP)-response element. We found that quercetin reduces the promoter activity of apoB, driven by the enforced expression of C/EBPβ. Quercetin had no effect on either mRNA or protein levels of C/EBPβ. In contrast, we found that quercetin inhibits the transcriptional activity of C/EBPβ but not its recruitment to the apoB promoter. On the exposure of Caco-2 cells to quercetin 3-O-glucuronide, which is in a cell-impermeable form, no notable change in apoB mRNA was observed, suggesting an intracellular action of quercetin. In vitro interaction experiments using quercetin-conjugated beads revealed that quercetin binds to C/EBPβ. Our results describe a novel regulatory mechanism of transcription of apolipoprotein genes by quercetin in the intestinal enterocytes. PMID:25875015

  19. Quercetin inhibits inflammatory bone resorption in a mouse periodontitis model.

    PubMed

    Napimoga, Marcelo H; Clemente-Napimoga, Juliana T; Macedo, Cristina G; Freitas, Fabiana F; Stipp, Rafael N; Pinho-Ribeiro, Felipe A; Casagrande, Rubia; Verri, Waldiceu A

    2013-12-27

    Periodontitis is a disease that leads to bone destruction and represents the main cause of tooth loss in adults. The development of aggressive periodontitis has been associated with increased inflammatory response that is induced by the presence of a subgingival biofilm containing Aggregatibacter actinomycetemcomitans. The flavonoid quercetin (1) is widespread in vegetables and fruits and exhibits many biological properties for possible medical and clinical applications such as its anti-inflamatory and antioxidant effects. Thus, in the present study, the properties of 1 have been evaluated in bone loss and inflammation using a mouse periodontitis model induced by A. actinomycetemcomitans infection. Subcutaneous treatment with 1 reduced A. actinomycetemcomitans-induced bone loss and IL-1β, TNF-α, IL-17, RANKL, and ICAM-1 production in the gingival tissue without affecting bacterial counts. These results demonstrated that quercetin exhibits protective effects in A. actinomycetemcomitans-induced periodontitis in mice by modulating cytokine and ICAM-1 production. PMID:24246038

  20. Synthesis, characterization and antioxidant activity copper-quercetin complex

    NASA Astrophysics Data System (ADS)

    Bukhari, S. Birjees; Memon, Shahabuddin; Mahroof-Tahir, M.; Bhanger, M. I.

    2009-01-01

    Quercetin (3,3',4',5,7-pentahydroxyflavone) one of the most abundant dietary flavonoids, has been investigated in the presence of Cu(II) in methanol. The spectroscopic studies (UV-vis, 1H NMR and IR) were useful to assess the relevant interaction of Quercetin with Cu(II) ions, the chelation sites and dependence of the complex structure from the metal/ligand ratio. A 1:2 (L:M) complex was indicated by Job's method of continuous variation, which was applied to ascertain the stoichiometric composition of the complex. The antioxidant activities of the compounds were evaluated by using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging method. The complexed flavonoid was much more effective free radical scavengers than the free flavonoids.

  1. Biosynthesis of two quercetin O-diglycosides in Escherichia coli.

    PubMed

    An, Dae Gyun; Yang, So Mi; Kim, Bong Gyu; Ahn, Joong-Hoon

    2016-06-01

    Various flavonoid glycosides are found in nature, and their biological activities are as variable as their number. In some cases, the sugar moiety attached to the flavonoid modulates its biological activities. Flavonoid glycones are not easily synthesized chemically. Therefore, in this study, we attempted to synthesize quercetin 3-O-glucosyl (1→2) xyloside and quercetin 3-O-glucosyl (1→6) rhamnoside (also called rutin) using two uridine diphosphate-dependent glycosyltransferases (UGTs) in Escherichia coli. To synthesize quercetin 3-O-glucosyl (1→2) xyloside, sequential glycosylation was carried out by regulating the expression time of the two UGTs. AtUGT78D2 was subcloned into a vector controlled by a Tac promoter without a lacI operator, while AtUGT79B1 was subcloned into a vector controlled by a T7 promoter. UDP-xyloside was supplied by concomitantly expressing UDP-glucose dehydrogenase (ugd) and UDP-xyloside synthase (UXS) in the E. coli. Using these strategies, 65.0 mg/L of quercetin 3-O-glucosyl (1→2) xyloside was produced. For the synthesis of rutin, one UGT (BcGT1) was integrated into the E. coli chromosome and the other UGT (Fg2) was expressed in a plasmid along with RHM2 (rhamnose synthase gene 2). After optimization of the initial cell concentration and incubation temperature, 119.8 mg/L of rutin was produced. The strategies used in this study thus show promise for the synthesis of flavonoid diglucosides in E. coli. PMID:26931782

  2. Hypoxia- and radiation-inducible, breast cell-specific targeting of retroviral vectors

    SciTech Connect

    Lipnik, Karoline; Greco, Olga; Scott, Simon; Knapp, Elzbieta; Mayrhofer, Elisabeth; Rosenfellner, Doris; Guenzburg, Walter H.; Salmons, Brian; Hohenadl, Christine . E-mail: christine.hohenadl@vu-wien.ac.at

    2006-05-25

    To facilitate a more efficient radiation and chemotherapy of mammary tumours, synthetic enhancer elements responsive to hypoxia and ionizing radiation were coupled to the mammary-specific minimal promoter of the murine whey acidic protein (WAP) encoding gene. The modified WAP promoter was introduced into a retroviral promoter conversion (ProCon) vector. Expression of a transduced reporter gene in response to hypoxia and radiation was analysed in stably infected mammary cancer cell lines and an up to 9-fold increase in gene expression demonstrated in comparison to the respective basic vector. Expression analyses in vitro, moreover, demonstrated a widely preserved mammary cell-specific promoter activity. For in vivo analyses, xenograft tumours consisting of infected human mammary adenocarcinoma cells were established in SCID/beige mice. Immunohistochemical analyses demonstrated a hypoxia-specific, markedly increased WAP promoter-driven expression in these tumours. Thus, this retroviral vector will facilitate a targeted gene therapeutic approach exploiting the unique environmental condition in solid tumours.

  3. Quercetin, not caffeine, is a major neuroprotective component in coffee.

    PubMed

    Lee, Moonhee; McGeer, Edith G; McGeer, Patrick L

    2016-10-01

    Epidemiologic studies indicate that coffee consumption reduces the risk of Parkinson's disease and Alzheimer's disease. To determine the factors involved, we examined the protective effects of coffee components. The test involved prevention of neurotoxicity to SH-SY5Y cells that was induced by lipopolysaccharide plus interferon-γ or interferon-γ released from activated microglia and astrocytes. We found that quercetin, flavones, chlorogenic acid, and caffeine protected SH-SY5Y cells from these toxins. They also reduced the release of tumor necrosis factor-α and interleukin-6 from the activated microglia and astrocytes and attenuated the activation of proteins from P38 mitogen-activated protein kinase (MAPK) and nuclear factor kappa light chain enhancer of activated B cells (NFκB). After exposure to toxin containing glial-stimulated conditioned medium, we also found that quercetin reduced oxidative/nitrative damage to DNA, as well as to the lipids and proteins of SH-SY5Y cells. There was a resultant increase in [GSH]i in SH-SY5Y cells. The data indicate that quercetin is the major neuroprotective component in coffee against Parkinson's disease and Alzheimer's disease. PMID:27479153

  4. Benzbromarone, Quercetin, and Folic Acid Inhibit Amylin Aggregation.

    PubMed

    López, Laura C; Varea, Olga; Navarro, Susanna; Carrodeguas, José A; Sanchez de Groot, Natalia; Ventura, Salvador; Sancho, Javier

    2016-01-01

    Human Amylin, or islet amyloid polypeptide (hIAPP), is a small hormone secreted by pancreatic β-cells that forms aggregates under insulin deficiency metabolic conditions, and it constitutes a pathological hallmark of type II diabetes mellitus. In type II diabetes patients, amylin is abnormally increased, self-assembled into amyloid aggregates, and ultimately contributes to the apoptotic death of β-cells by mechanisms that are not completely understood. We have screened a library of approved drugs in order to identify inhibitors of amylin aggregation that could be used as tools to investigate the role of amylin aggregation in type II diabetes or as therapeutics in order to reduce β-cell damage. Interestingly, three of the compounds analyzed-benzbromarone, quercetin, and folic acid-are able to slow down amylin fiber formation according to Thioflavin T binding, turbidimetry, and Transmission Electron Microscopy assays. In addition to the in vitro assays, we have tested the effect of these compounds in an amyloid toxicity cell culture model and we have found that one of them, quercetin, has the ability to partly protect cultured pancreatic insulinoma cells from the cytotoxic effect of amylin. Our data suggests that quercetin can contribute to reduce oxidative damage in pancreatic insulinoma β cells by modulating the aggregation propensity of amylin. PMID:27322259

  5. Benzbromarone, Quercetin, and Folic Acid Inhibit Amylin Aggregation

    PubMed Central

    López, Laura C.; Varea, Olga; Navarro, Susanna; Carrodeguas, José A.; Sanchez de Groot, Natalia; Ventura, Salvador; Sancho, Javier

    2016-01-01

    Human Amylin, or islet amyloid polypeptide (hIAPP), is a small hormone secreted by pancreatic β-cells that forms aggregates under insulin deficiency metabolic conditions, and it constitutes a pathological hallmark of type II diabetes mellitus. In type II diabetes patients, amylin is abnormally increased, self-assembled into amyloid aggregates, and ultimately contributes to the apoptotic death of β-cells by mechanisms that are not completely understood. We have screened a library of approved drugs in order to identify inhibitors of amylin aggregation that could be used as tools to investigate the role of amylin aggregation in type II diabetes or as therapeutics in order to reduce β-cell damage. Interestingly, three of the compounds analyzed—benzbromarone, quercetin, and folic acid—are able to slow down amylin fiber formation according to Thioflavin T binding, turbidimetry, and Transmission Electron Microscopy assays. In addition to the in vitro assays, we have tested the effect of these compounds in an amyloid toxicity cell culture model and we have found that one of them, quercetin, has the ability to partly protect cultured pancreatic insulinoma cells from the cytotoxic effect of amylin. Our data suggests that quercetin can contribute to reduce oxidative damage in pancreatic insulinoma β cells by modulating the aggregation propensity of amylin. PMID:27322259

  6. Antagonism of quercetin against tremor induced by unilateral striatal lesion of 6-OHDA in rats.

    PubMed

    Mu, Xin; Yuan, Xia; Du, Li-Da; He, Guo-Rong; Du, Guan-Hua

    2016-01-01

    Quercetin, a flavonoid present in many plants, is reported to be effective in models of neurodegenerative diseases. The aim of the present study was to evaluate the anti-tremor effects of quercetin in 6-hydroxydopamine (6-OHDA)-induced rat model of Parkinson's disease. In rats, quercetin had no effect on apomorphine-induced rotations, but it could significantly attenuate muscle tremor of 6-OHDA lesioned rats. Interestingly, quercetin could decrease the burst frequency in a dose- and time-dependent manner. These results suggest that quercetin may have a protective effect on models to mimic muscle tremors of Parkinson's disease. This effect of quercetin may be associated with serotonergic system, but further study is needed. PMID:26217978

  7. Synthesis and characterization of a novel antioxidant RS4 by esterifying carboxymethyl sweetpotato starch with quercetin.

    PubMed

    Lv, Xia; Ye, Fayin; Li, Jinfeng; Ming, Jian; Zhao, Guohua

    2016-11-01

    Quercetin is grafted to carboxymethyl sweetpotato starch (CMSS) by esterification. Upon esterification, the water solubility of CMSS decreases and the CMSS-quercetin conjugates (CMSS-Q) are yellowish. FT-IR and 1H NMR indicated the covalent attachment of quercetin to CMSS. Thermogravimetry revealed the superior thermal stability of CMSS-Q over CMSS and native sweetpotato starch (NSS). The in vitro digestibility assays showed that CMSS is highly resistant to digestion while the quercetin graft with degree of substitution (DS) above 0.074 slightly increased its digestibility. The quercetin graft imparted CMSS with strong antioxidant activity and enhanced its thermal stability, which increased with quercetin DS. In vitro cyotoxicity assessment revealed that CMSS-Q is as safe as CMSS and NSS. This study showed that CMSS-Q is a novel antioxidant-resistant starch in RS4 form. PMID:27516278

  8. Different profiles of quercetin metabolites in rat plasma: comparison of two administration methods.

    PubMed

    Kawai, Yoshichika; Saito, Satomi; Nishikawa, Tomomi; Ishisaka, Akari; Murota, Kaeko; Terao, Junji

    2009-03-23

    The bioavailability of polyphenols in human and rodents has been discussed regarding their biological activity. We found different metabolite profiles of quercetin in rat plasma between two administration procedures. A single intragastric administration (50 mg/kg) resulted in the appearance of a variety of metabolites in the plasma, whereas only a major fraction was detected by free access (1% quercetin). The methylated/non-methylated metabolites ratio was much higher in the free access group. Mass spectrometric analyses showed that the fraction from free access contained highly conjugated quercetin metabolites such as sulfo-glucuronides of quercetin and methylquercetin. The metabolite profile of human plasma after an intake of onion was similar to that with intragastric administration in rats. In vitro oxidation of human low-density lipoprotein showed that methylation of the catechol moiety of quercetin significantly attenuated the antioxidative activity. These results might provide information about the bioavailability of quercetin when conducting animal experiments. PMID:19270373

  9. Binding, stability, and antioxidant activity of quercetin with soy protein isolate particles.

    PubMed

    Wang, Yufang; Wang, Xiaoyong

    2015-12-01

    This work is to study the potential of particles fabricated from soy protein isolate (SPI) as a protective carrier for quercetin. When the concentration of SPI particles increases from 0 to 0.35 g/L, quercetin gives a gradually increased fluorescence intensity and fluorescence anisotropy. The addition of quercetin can highly quench the intrinsic fluorescence of SPI particles. These results are explained in terms of the binding of quercetin to the hydrophobic pockets of SPI particles mainly through the hydrophobic force together with the hydrogen bonding. The small difference in the binding constants at 25 and 40 °C suggests the structural stability of SPI particles. The relative changes in values of Gibbs energy, enthalpy, and entropy indicate that the binding of quercetin with SPI particles is spontaneous and hydrophobic interaction is the major force. Furthermore, SPI particles are superior to native SPI for improving the stability and radical scavenging activity of quercetin. PMID:26041159

  10. Quercetin from shallots (Allium cepa L. var. aggregatum) is more bioavailable than its glucosides.

    PubMed

    Wiczkowski, Wieslaw; Romaszko, Jerzy; Bucinski, Adam; Szawara-Nowak, Dorota; Honke, Joanna; Zielinski, Henryk; Piskula, Mariusz K

    2008-05-01

    The lipophilic character of quercetin suggests that it can cross enterocyte membranes via simple diffusion. Therefore, it should be more bioavailable than its glucosides, which require preliminary hydrolysis or active transport for absorption. However, the published human studies show that quercetin is less bioavailable than its glucosides. Assuming that low bioavailability of quercetin aglycone provided to humans as a pure substance is the result of its low solubility in the digestive tract, we studied its bioavailability from dietary sources in which quercetin was dispersed in the food matrix. In a randomized crossover study, 9 volunteers took a single dose of either shallot flesh (99.2% quercetin glucosides and 0.8% quercetin aglycone) or dry shallot skin (83.3% quercetin aglycone and 16.7% quercetin glucosides), providing 1.4 mg quercetin per kg of body weight. Blood samples were collected before and after consumption of shallot preparations. Plasma quercetin was measured on HPLC with electrochemical detection after plasma enzymatic treatment. The maximum plasma quercetin concentration of 1.02 +/- 0.13 micromol/L was reached at 2.33 +/- 0.50 h after shallot flesh consumption compared with 3.95 +/- 0.62 micromol/L at 2.78 +/- 0.15 h after dry skin consumption. The area under the concentration-time curve after dry skin consumption was 47.23 +/- 7.53 micromol x h(-1) x L(-1) and was significantly higher than that after shallot flesh intake (22.23 +/- 2.32 micromol x h(-1) x L(-1)). When provided along with dietary sources, quercetin aglycone is more bioavailable than its glucosides in humans. Results point to the food matrix as a key factor. PMID:18424596

  11. Preparation and evaluation of quercetin-loaded lecithin-chitosan nanoparticles for topical delivery

    PubMed Central

    Tan, Qi; Liu, Weidong; Guo, Chenyu; Zhai, Guangxi

    2011-01-01

    Background The purpose of this study was to investigate lecithin-chitosan nanoparticles as a topical delivery system for quercetin. Methods Tocopheryl propylene glycol succinate was chosen to be the surfactant for the nanosystem. The mean particle size of the nanoparticles was 95.3 nm, and the entrapment efficiency and drug loading for quercetin were 48.5% and 2.45%, respectively. Topical delivery in vitro and in vivo of the quercetin-loaded nanoparticles was evaluated using quercetin propylene glycol solution as the control. Results Compared with quercetin solution, the quercetin-loaded nanoparticles showed higher permeation ability, and significantly increased accumulation of quercetin in the skin, especially in the epidermis. Microstructure observation of the skin surface after administration indicated that the interaction between ingredients of the nanoparticles and the skin surface markedly changed the morphology of the stratum corneum and disrupted the corneocyte layers, thus facilitating the permeation and accumulation of quercetin in skin. Conclusion Lecithin-chitosan nanoparticles are a promising carrier for topical delivery of quercetin. PMID:21904452

  12. Effects of Functional Groups and Sugar Composition of Quercetin Derivatives on Their Radical Scavenging Properties.

    PubMed

    Kato, Komei; Ninomiya, Masayuki; Tanaka, Kaori; Koketsu, Mamoru

    2016-07-22

    Quercetin derivatives are widespread in the plant kingdom and exhibit various biological actions. The aim of this study was to investigate the structure-activity relationships of quercetin derivatives, with a focus on the influence of functional groups and sugar composition on their antioxidant capacity. A series of quercetin derivatives were therefore prepared and assessed for their DPPH radical scavenging properties. Isoquercetin O-gallates were more potent radical scavengers than quercetin. The systematic analysis highlights the importance of the distribution of hydroxy substituents in isoquercetin O-gallates to their potency. PMID:27314621

  13. A new acylated quercetin glycoside from the leaves of Stevia rebaudiana Bertoni.

    PubMed

    Li, Jun; Jiang, Hua; Shi, Renbing

    2009-01-01

    A new acylated quercetin glycoside quercetin-3-O-(4'''-O-trans-caffeoyl)-alpha-L-rhamnopyranosyl-(1-->6)-beta-D-galacopyranoside (1), along with luteolin (2), quercetin (3), luteolin-7-O-beta-D-glucoside (4), apigenin-7-O-beta-D-glucoside (5), quercitrin (6), quercetin-3-O-beta-D-arabinoside (7) and 4,5-di-O-caffeoyl quinic acid (8) have been isolated from the leaves of Stevia rebaudiana Bertoni. The structures of these compounds were determined by spectroscopic methods (1H- and 13C-NMR, IR and MS) and by 2D-NMR experiments. PMID:19809909

  14. Cell-specific synaptic plasticity induced by network oscillations

    PubMed Central

    Zarnadze, Shota; Bäuerle, Peter; Santos-Torres, Julio; Böhm, Claudia; Schmitz, Dietmar; Geiger, Jörg RP

    2016-01-01

    Gamma rhythms are known to contribute to the process of memory encoding. However, little is known about the underlying mechanisms at the molecular, cellular and network levels. Using local field potential recording in awake behaving mice and concomitant field potential and whole-cell recordings in slice preparations we found that gamma rhythms lead to activity-dependent modification of hippocampal networks, including alterations in sharp wave-ripple complexes. Network plasticity, expressed as long-lasting increases in sharp wave-associated synaptic currents, exhibits enhanced excitatory synaptic strength in pyramidal cells that is induced postsynaptically and depends on metabotropic glutamate receptor-5 activation. In sharp contrast, alteration of inhibitory synaptic strength is independent of postsynaptic activation and less pronounced. Further, we found a cell type-specific, directionally biased synaptic plasticity of two major types of GABAergic cells, parvalbumin- and cholecystokinin-expressing interneurons. Thus, we propose that gamma frequency oscillations represent a network state that introduces long-lasting synaptic plasticity in a cell-specific manner. DOI: http://dx.doi.org/10.7554/eLife.14912.001 PMID:27218453

  15. Cell-specific synaptic plasticity induced by network oscillations.

    PubMed

    Zarnadze, Shota; Bäuerle, Peter; Santos-Torres, Julio; Böhm, Claudia; Schmitz, Dietmar; Geiger, Jörg Rp; Dugladze, Tamar; Gloveli, Tengis

    2016-01-01

    Gamma rhythms are known to contribute to the process of memory encoding. However, little is known about the underlying mechanisms at the molecular, cellular and network levels. Using local field potential recording in awake behaving mice and concomitant field potential and whole-cell recordings in slice preparations we found that gamma rhythms lead to activity-dependent modification of hippocampal networks, including alterations in sharp wave-ripple complexes. Network plasticity, expressed as long-lasting increases in sharp wave-associated synaptic currents, exhibits enhanced excitatory synaptic strength in pyramidal cells that is induced postsynaptically and depends on metabotropic glutamate receptor-5 activation. In sharp contrast, alteration of inhibitory synaptic strength is independent of postsynaptic activation and less pronounced. Further, we found a cell type-specific, directionally biased synaptic plasticity of two major types of GABAergic cells, parvalbumin- and cholecystokinin-expressing interneurons. Thus, we propose that gamma frequency oscillations represent a network state that introduces long-lasting synaptic plasticity in a cell-specific manner. PMID:27218453

  16. Cell-specific analysis of tracheobronchial secretory cells and secretions

    SciTech Connect

    Finkbeiner, W.E.

    1989-01-01

    In these studies, two methods (cell culture and monoclonal antibody production) that allowed cell-specific analysis of tracheobronchial secretion were used. Bovine tracheal submucosal gland cells were isolated, placed into culture and serially propagated. In culture, the cells maintained features of serous cells. The cells incorporated {sup 35}S into high molecular weight molecules. {beta}-adrenergic agonists stimulated release of radiolabeled molecules and elevations in intracellular cAMP levels, responses that could be blocked by the {beta}-adrenergic antagonist propranolol. Cyclic AMP appeared to be involved in the stimulus-secretion coupling events in serous cells since the phosphodiesterase inhibitor 1-methyl-3-isobutylxanthine potentiated the effects of isoproterenol on the secretory response and the elevation of intracellular cAMP levels. Furthermore, cAMP analogues elicited a secretory response in the absence of cAMP. The phosphorylation state of several cytosolic and particulate phosphoproteins was altered by cAMP-activated kinase activity. Monoclonal antibodies were produced against human airway secretions.

  17. Oral administration of quercetin inhibits bone loss in rat model of diabetic osteopenia.

    PubMed

    Liang, Wei; Luo, Zhonghua; Ge, Shuhua; Li, Mo; Du, Junjie; Yang, Min; Yan, Ming; Ye, Zhengxu; Luo, Zhuojing

    2011-11-16

    Diabetic osteopenia can result in an increased incidence of bone fracture and a delay in fracture healing. Quercetin, one of the most widely distributed flavonoids in plants, possesses antioxidant property and beneficial effect on osteoporosis in ovariectomized mice. All these properties make quercetin a potential candidate for controlling the development of diabetic osteopenia. Therefore, the present study was designed to investigate the putative beneficial effect of quercetin on diabetic osteopenia in rats. Diabetes mellitus was induced by streptozotocin. The diabetic rats received daily oral administration of quercetin (5mg/kg, 30 mg/kg and 50mg/kg) for 8 weeks, which was started at 4 weeks after streptozotocin injection. Quercetin at 5mg/kg showed little effect on diabetic osteopenia, while quercetin at 30 mg/kg and 50mg/kg could increase the decreased serum osteocalcin, serum alkaline phosphatase activity, and urinary deoxypyridinoline in diabetic rats. In addition, quercetin (30 mg/kg and 50mg/kg) could partially reverse the decreased biomechanical quality and the impaired micro-architecture of the femurs in diabetic rats. Histomorphometric analysis showed that both decreased bone formation and resorption were observed in diabetic rats, which was partially restored by quercetin (30 mg/kg and 50mg/kg). Further investigations showed that quercetin significantly lowered the oxidative DNA damage level, up-regulated the total serum antioxidant capability and the activity of serum antioxidants in diabetic rats. All those findings indicate the beneficial effect of quercetin on diabetic osteopenia in rats, and raise the possibility of developing quercetin as potential drugs or an ingredient in diet for controlling diabetic osteopenia. PMID:21914440

  18. Quercetin prevents experimental glucocorticoid-induced osteoporosis: a comparative study with alendronate.

    PubMed

    Derakhshanian, Hoda; Djalali, Mahmoud; Djazayery, Abolghassem; Nourijelyani, Keramat; Ghadbeigi, Sajad; Pishva, Hamideh; Saedisomeolia, Ahmad; Bahremand, Arash; Dehpour, Ahmad Reza

    2013-05-01

    Glucocorticoid-induced osteoporosis (GIO) is the most common type of secondary osteoporosis. The aim of this study was to compare the efficacy of quercetin, a plant-derived flavonoid, with alendronate in the prevention of GIO. Fifty-six Sprague-Dawley rats were randomly distributed among 7 groups (8 rats per group) and treated for 6 weeks with one of the following: (i) normal saline; (ii) 40 mg methylprednisolone sodium succinate (MP)/kg body mass; (iii) MP + 40 μg alendronate/kg; (iv) MP + 50 mg quercetin/kg; (v) MP + 40 μg alendronate/kg + 50 mg quercetin/kg; (vi) MP + 150 mg quercetin/kg; and (vii) MP + 40 μg alendronate/kg + 150 mg quercetin/kg. MP and alendronate were injected subcutaneously and quercetin was administered by oral gavage 3 days a week. At the end of the study, femur breaking strength was significantly decreased as a consequence of MP injection. This decrease was completely compensated for in groups receiving 50 mg quercetin/kg plus alendronate, and 150 mg quercetin/kg with or without alendronate. Quercetin noticeably elevated osteocalcin as a bone formation marker, while alendronate did not show such an effect. In addition, administration of 150 mg quercetin/kg increased femoral trabecular and cortical thickness by 36% and 22%, respectively, compared with the MP-treated group. These data suggest that 150 mg quercetin/kg, alone or in combination with alendronate, can completely prevent GIO through its bone formation stimulatory effect. PMID:23656499

  19. Anthocyanin indexes, quercetin, kaempferol, and myricetin concentration in leaves and fruit of Abutilon theophrasti Medik. genetic resources

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anthocyanin indexes, quercetin, kaempferol, and myricetin may provide industry with potential new medicines or nutraceuticals. Velvetleaf (Abutilon theophrasti Medik) leaves from 42 accessions were analyzed for anthocyanin indexes while both leaves and fruit were used for quercetin, kaempferol, and ...

  20. Cell-specific modulation of surfactant proteins by ambroxol treatment.

    PubMed

    Seifart, Carola; Clostermann, Ursula; Seifart, Ulf; Müller, Bernd; Vogelmeier, Claus; von Wichert, Peter; Fehrenbach, Heinz

    2005-02-15

    Ambroxol [trans-4-(2-amino-3,5-dibromobenzylamino)-cyclohexanole hydrochloride], a mucolytic agent, was postulated to provide surfactant stimulatory properties and was previously used to prevent surfactant deficiency. Currently, the underlying mechanisms are not exactly clear. Because surfactant homeostasis is regulated by surfactant-specific proteins (SP), we analyzed protein amount and mRNA expression in whole lung tissue, isolated type II pneumocytes and bronchoalveolar lavage of Sprague-Dawley rats treated with ambroxol i.p. (75 mg/kg body weight, twice a day [every 12 h]). The methods used included competitive polymerase chain reaction (RT-PCR), Northern blotting, Western immunoblotting, and immunohistochemistry. In isolated type II pneumocytes of ambroxol-treated animals, SP-C protein and mRNA content were increased, whereas SP-A, -B and -D protein, mRNA, and immunoreactivity remained unaffected. However, ambroxol treatment resulted in a significant increase of SP-B and in a decrease of SP-D in whole lung tissue with enhanced immunostaining for SP-B in Clara Cells. SP-A and SP-D were significantly decreased in BAL fluid of ambroxol-treated animals. The data suggest that surfactant protein expression is modulated in a cell-specific manner by ambroxol, as type II pneumocytes exhibited an increase in SP-C, whereas Clara cells exhibited an increase in the immunoreactivity for SP-B accounting for the increased SP-B content of whole lung tissue. The results indicate that ambroxol may exert its positive effects, observed in the treatment of diseases related to surfactant deficiency, via modulation of surfactant protein expression. PMID:15694461

  1. Cell-specific modulation of surfactant proteins by ambroxol treatment

    SciTech Connect

    Seifart, Carola . E-mail: zwiebel@mailer.uni-marburg.de; Clostermann, Ursula; Seifart, Ulf

    2005-02-15

    Ambroxol [trans-4-(2-amino-3,5-dibromobenzylamino)-cyclohexanole hydrochloride], a mucolytic agent, was postulated to provide surfactant stimulatory properties and was previously used to prevent surfactant deficiency. Currently, the underlying mechanisms are not exactly clear. Because surfactant homeostasis is regulated by surfactant-specific proteins (SP), we analyzed protein amount and mRNA expression in whole lung tissue, isolated type II pneumocytes and bronchoalveolar lavage of Sprague-Dawley rats treated with ambroxol i.p. (75 mg/kg body weight, twice a day [every 12 h]). The methods used included competitive polymerase chain reaction (RT-PCR), Northern blotting, Western immunoblotting, and immunohistochemistry. In isolated type II pneumocytes of ambroxol-treated animals, SP-C protein and mRNA content were increased, whereas SP-A, -B and -D protein, mRNA, and immunoreactivity remained unaffected. However, ambroxol treatment resulted in a significant increase of SP-B and in a decrease of SP-D in whole lung tissue with enhanced immunostaining for SP-B in Clara Cells. SP-A and SP-D were significantly decreased in BAL fluid of ambroxol-treated animals. The data suggest that surfactant protein expression is modulated in a cell-specific manner by ambroxol, as type II pneumocytes exhibited an increase in SP-C, whereas Clara cells exhibited an increase in the immunoreactivity for SP-B accounting for the increased SP-B content of whole lung tissue. The results indicate that ambroxol may exert its positive effects, observed in the treatment of diseases related to surfactant deficiency, via modulation of surfactant protein expression.

  2. Designing polymeric microparticulate drug delivery system for hydrophobic drug quercetin

    PubMed Central

    Hazra, Moumita; Dasgupta Mandal, Dalia; Mandal, Tamal; Bhuniya, Saikat; Ghosh, Mallika

    2015-01-01

    The aim of this study was to investigate pharmaceutical potentialities of a polymeric microparticulate drug delivery system for modulating the drug profile of poorly water-soluble quercetin. In this research work two cost effective polymers sodium alginate and chitosan were used for entrapping the model drug quercetin through ionic cross linking method. In vitro drug release, swelling index, drug entrapment efficiency, Fourier Transforms Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD) and Differential Scanning Calorimetric (DSC) studies were also done for physicochemical characterization of the formulations. Swelling index and drug release study were done at a pH of 1.2, 6.8 and 7.4 to evaluate the GI mimetic action which entails that the swelling and release of the all the Formulation1 (F1), Formulation2 (F2) and Formulation3 (F3) at pH 1.2 were minimal confirming the prevention of drug release in the acidic environment of stomach. Comparatively more sustained release was seen from the formulations F2 & F3 at pH 6.8 and pH 7.4 after 7 h of drug release profiling. Drug entrapment efficiency of the formulations shows in F1 (D:C:A = 2:5:30) was approximately 70% whereas the increase in chitosan concentration in F2 (D:C:A = 2:10:30) has shown an entrapment efficiency of 81%. But the comparative further increase of chitosan concentration in F3 (D:C:A = 2:15:30) has shown a entrapment of 80% which is not having any remarkable difference from F2. The FTIR analysis of drug, polymers and the formulations indicated the compatibility of the drug with the polymers. The smoothness of microspheres in F2 & F3 was confirmed by Scanning Electron Microscopy (SEM). However F1 microsphere has shown more irregular shape comparatively. The DSC studies indicated the absence of drug-polymer interaction in the microspheres. Our XRD studies have revealed that when pure drug exhibits crystalline structure with less dissolution profile

  3. Incorporation of quercetin in lipid microparticles: effect on photo- and chemical-stability.

    PubMed

    Scalia, Santo; Mezzena, Matteo

    2009-01-15

    Lipid microparticles loaded with the flavonoid, quercetin were developed in order to enhance its stability in topical formulations. The microparticles were produced using tristearin as the lipid material and phosphatidylcholine as the emulsifier. The obtained lipoparticles were characterized by release studies, scanning electron microscopy and powder X-ray diffractometry. The quercetin loading was 12.1% (w/w). Free or microencapsulated quercetin was introduced in a model cream formulation (oil-in-water emulsion) and irradiated with a solar simulator. The extent of photodegradation was measured by high-performance liquid chromatography. The light-induced decomposition of quercetin in the cream vehicle was markedly decreased by incorporation into the lipid microparticles (the extent of degradation was 23.1+/-3.6% for non-encapsulated quercetin compared to 11.9+/-2.5% for the quercetin-loaded microparticles) and this photostabilization effect was maintained over time. Moreover, the chemical instability of quercetin, during 3-month storage of the formulations at room temperature and in the dark, was almost completely suppressed by the lipid microparticle system. Therefore incorporation of quercetin in lipoparticles represents an effective strategy to enhance its stability in dermatological products. PMID:19042102

  4. Preventive effect of dietary quercetin on disuse muscle atrophy by targeting mitochondria in denervated mice.

    PubMed

    Mukai, Rie; Matsui, Naoko; Fujikura, Yutaka; Matsumoto, Norifumi; Hou, De-Xing; Kanzaki, Noriyuki; Shibata, Hiroshi; Horikawa, Manabu; Iwasa, Keiko; Hirasaka, Katsuya; Nikawa, Takeshi; Terao, Junji

    2016-05-01

    Quercetin is a major dietary flavonoid in fruits and vegetables. We aimed to clarify the preventive effect of dietary quercetin on disuse muscle atrophy and the underlying mechanisms. We established a mouse denervation model by cutting the sciatic nerve in the right leg (SNX surgery) to lack of mobilization in hind-limb. Preintake of a quercetin-mixed diet for 14days before SNX surgery prevented loss of muscle mass and atrophy of muscle fibers in the gastrocnemius muscle (GM). Phosphorylation of Akt, a key phosphorylation pathway of suppression of protein degradation, was activated in the quercetin-mixed diet group with and without SNX surgery. Intake of a quercetin-mixed diet suppressed the generation of hydrogen peroxide originating from mitochondria and elevated mitochondrial peroxisome proliferator-activated receptor-γ coactivator 1α mRNA expression as well as NADH dehydrogenase 4 expression in the GM with SNX surgery. Quercetin and its conjugated metabolites reduced hydrogen peroxide production in the mitochondrial fraction obtained from atrophied muscle. In C2C12 myotubes, quercetin reached the mitochondrial fraction. These findings suggest that dietary quercetin can prevent disuse muscle atrophy by targeting mitochondria in skeletal muscle tissue through protecting mitochondria from decreased biogenesis and reducing mitochondrial hydrogen peroxide release, which can be related to decreased hydrogen peroxide production and/or improvements on antioxidant capacity of mitochondria. PMID:27133425

  5. Effects of quercetin on oxidative stress and memory retrieval in kindled rats.

    PubMed

    Nassiri-Asl, Marjan; Moghbelinejad, Sahar; Abbasi, Esmail; Yonesi, Fatemeh; Haghighi, Mohammad-Reza; Lotfizadeh, Mina; Bazahang, Parisa

    2013-08-01

    Flavonoids are a class of polyphenolic compounds present in fruits and vegetables. Several studies have demonstrated a relationship between the consumption of flavonoid-rich diets and the prevention of human diseases including neurodegenerative disorders. Thus, we assessed the effect of quercetin (3,3',4',5,7-pentahydroxyflavone) on oxidative stress and memory retrieval using a step-through passive avoidance task in kindled rats. Quercetin (25, 50, and 100 mg/kg) was administered intraperitoneally (i.p.) before pentylenetetrazole (PTZ) every other day prior to the training. Retention tests were performed to assess memory in rats. Compared to control, pretreatment with 50 mg/kg of quercetin could attenuate seizure severity from the beginning of the kindling experiment by lowering the mean seizure stages. Moreover, quercetin 50 mg/kg significantly increased the step-through latency of the passive avoidance response compared to the control in the retention test. Malondialdehyde (MDA) levels were significantly increased in the quercetin groups compared to the PTZ group in the hippocampus and cerebral cortex following PTZ kindling. In the quercetin groups, higher sulfhydryl (SH) contents were not observed compared to the PTZ group. These results indicate that quercetin at a specific dose results in decreased seizure severity during kindling and performance improvement in a passive avoidance task in kindled rats. All doses of quercetin led to increased oxidative stress in the hippocampi and cerebral cortices of kindled rats. PMID:23747498

  6. The effect of quercetin phase II metabolism on its MRP1 and MRP2 inhibiting potential.

    PubMed

    van Zanden, Jelmer J; van der Woude, Hester; Vaessen, Judith; Usta, Mustafa; Wortelboer, Heleen M; Cnubben, Nicole H P; Rietjens, Ivonne M C M

    2007-07-15

    The present study characterises the effect of phase II metabolism, especially methylation and glucuronidation, of the model flavonoid quercetin on its capacity to inhibit human MRP1 and MRP2 activity in Sf9 inside-out vesicles. The results obtained reveal that 3'-O-methylation does not affect the MRP inhibitory potential of quercetin. However, 4'-O-methylation appeared to reduce the potential to inhibit both MRP1 and MRP2. In contrast, glucuronidation in general, and especially glucuronidation at the 7-hydroxylmoiety, resulting in 7-O-glucuronosyl quercetin, significantly increased the potential of quercetin to inhibit MRP1 and MRP2 mediated calcein transport with inhibition of MRP1 being generally more effective than that of MRP2. Overall, the results of this study reveal that the major phase II metabolites of quercetin are equally potent or even better inhibitors of human MRP1 and MRP2 than quercetin itself. This finding indicates that phase II metabolism of quercetin could enhance the potential use of quercetin- or flavonoids in general-as an inhibitor to overcome MRP-mediated multidrug resistance. PMID:17509533

  7. The flavonoid quercetin induces apoptosis and inhibits JNK activation in intimal vascular smooth muscle cells

    SciTech Connect

    Perez-Vizcaino, Francisco . E-mail: fperez@med.ucm.es; Bishop-Bailley, David; Lodi, Federica; Duarte, Juan; Cogolludo, Angel; Moreno, Laura; Bosca, Lisardo; Mitchell, Jane A.; Warner, Timothy D.

    2006-08-04

    Quercetin, the most abundant dietary flavonol, exerts vasodilator, anti-hypertensive, and anti-atherogenic effects and reduces the vascular remodelling associated with elevated blood pressure. Here, we have compared the effects of quercetin in intimal- and medial-type rat vascular smooth muscle cells (VSMC) in culture. After 48 h, quercetin reduced the viability of a polyclonal intimal-type cell line derived from neonatal aorta but not of a medial-type cell line derived from adult aorta. These differential effects were similar in both proliferating and quiescent VSMC. Quercetin also preferentially reduced the viability of intimal-type over medial-type VSMC in primary cultures derived from balloon-injured carotid arteries. The effects of quercetin on cell viability were mainly dependent upon induction of apoptosis, as demonstrated by nuclear condensation and fragmentation, and were unrelated to PPAR{gamma}, pro-oxidant effects or nitric oxide. The expression of MAPKs (ERK, p38, and JNK) and ERK phosphorylation were not different between intimal- and medial-type VSMC. p38 phosphorylation was negligible in both cell types. Medial-type showed a weak JNK phosphorylation while this was markedly increased in intimal-type cells. Quercetin reduced JNK phosphorylation but had no consistent effect on ERK phosphorylation. In conclusion, quercetin preferentially produced apoptosis in intimal-type compared to medial-type VSMC. This might play a role in the anti-atherogenic and anti-hypertensive effects of quercetin.

  8. Comparison between the effects of quercetin on seizure threshold in acute and chronic seizure models.

    PubMed

    Nassiri-Asl, Marjan; Hajiali, Farid; Taghiloo, Mina; Abbasi, Esmail; Mohseni, Fatemeh; Yousefi, Farbod

    2016-05-01

    Flavonoids are important constituents of food and beverages, and several studies have shown that they have neuroactive properties. Many of these compounds are ligands for γ-aminobutyric acid type A receptors in the central nervous system. This study aimed to investigate the anticonvulsant effects of quercetin (3,3',4',5,7-pentahydroxyflavone), which is a flavonoid found in plants, in rats treated with pentylenetetrazole in acute and chronic seizure models. Single intraperitoneal administration of quercetin did not show anticonvulsive effects against acute seizure. Similarly, multiple oral pretreatment with quercetin did not have protective effects against acute seizure. However, multiple intraperitoneal administration of quercetin (25 and 50 mg/kg) significantly increased time to death compared with the control (p < 0.001). However, quercetin pretreatment had no significant effects on the pattern of convulsion development during all periods of kindling. But on the test day, quercetin (100 mg/kg) could significantly increase generalized tonic-clonic seizure onset (GTCS) and decrease GTCS duration compared with the control (p < 0.01, p < 0.05). We conclude that quercetin has a narrow therapeutic dose range for anticonvulsant activities in vivo, and it has different effects on the seizure threshold. The different effects of quercetin on seizure threshold may occur through several mechanisms. PMID:24442347

  9. Effects of quercetin on pharmacokinetics of cefprozil in Chinese-Han male volunteers.

    PubMed

    Jia, Fei-Fei; Tan, Zhi-Rong; McLeod, Howard L; Chen, Yao; Ou-Yang, Dong-Sheng; Zhou, Hong-Hao

    2016-10-01

    1. The primary objective of this study was to evaluate the effects of quercetin on the pharmacokinetics of cefprozil. The secondary objective was to evaluate the safety of the combined use of cefprozil and quercetin. 2. An open-label, two-period, crossover phase I trial among 24 Han Chinese male subjects was conducted. Participants were given 500 mg of quercetin orally once daily for 15 d followed by single dose of cefprozil (500 mg) on day 15. Serum concentrations of cefprozil were then measured in all participants on day 15. A 15-d washout period was then assigned after which a 500 mg dose of cefprozil was administered and measured in the serum on day 36. 3. All subjects completed the trial, and no serious adverse events were reported. We measured mean serum concentrations of cefprozil in the presence and absence of quercetin in all participants. The maximum serum concentration of cefprozil in the presence of quercetin was 8.18 ug/ml (95% CI: 7.55-8.81) versus a maximum cefprozil concentration of 8.35 ug/ml (95% CI: 7.51-9.19) in the absence of quercetin. We conclude that the concurrent use of quercetin has no substantial effect on serum concentrations of orally administered cefprozil. 4. Co-administration of quercetin showed no statistically significant effects on the pharmacokinetics of cefprozil in healthy Chinese subjects. PMID:26928207

  10. Genetic expression profile analysis of the temporal inhibition of quercetin and naringenin on Lactobacillus rhamnosus GG

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The plant polyphenols, quercetin and naringenin, are considered healthy dietary compounds; however, little is known of their effects on the probiotic Lactobacillus rhamnosus GG (LGG). In this study, it was discovered that both quercetin and naringenin produced temporary inhibition of LGG growth, par...

  11. Dermal quercetin smartCrystals®: Formulation development, antioxidant activity and cellular safety.

    PubMed

    Hatahet, T; Morille, M; Hommoss, A; Dorandeu, C; Müller, R H; Bégu, S

    2016-05-01

    Flavonoids are natural plant pigments, which possess high antioxidative and antiradical activities. However, their poor water solubility led to a limited bioavailability. To overcome this major hurdle, quercetin nanocrystals were produced implementing smartCrystals® technology. This process combines bead milling and subsequent high-pressure homogenization at relatively low pressure (300bar). To test the possibility to develop a dermal formulation from quercetin smartCrystals®, quercetin nanosuspensions were admixed to Lutrol® F127 and hydroxythylcellulose nonionic gels. The physicochemical properties (morphology, size and charge), saturation solubility, dissolution velocity and the antioxidant properties (DPPH assay) as well as the cellular interaction of the produced quercetin smartCrystals® were studied and compared to crude quercetin powder. Quercetin smartCrystals® showed a strong increase in the saturation solubility and the dissolution velocity (7.6 fold). SmartCrystals® loaded or not into gels proved to be physically stable over a period of three months at 25°C. Interestingly, in vitro DPPH assay confirmed the preservation of quercetin antioxidative properties after nanonization. In parallel, the nanocrystalline form did not display cellular toxicity, even at high concentration (50μg/ml), as assayed on an epithelial cell line (VERO cells). In addition, the nanocrystalline form confirmed a protective activity for VERO cells against hydrogen peroxide induced toxicity in vitro. This new formulation presents a promising approach to deliver quercetin efficiently to skin in well-tolerated formulations. PMID:26948977

  12. Microsomal quercetin glucuronidation in rat small intestine depends on age and segment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    UDP-glucuronosyltransferase (UGT) activity toward the flavonoid quercetin and UGT protein were characterized in 3 equidistant small intestine (SI) segments from 4, 12, 18, and 28 mo male F344 rats, n=8/age using villin to control for enterocyte content. SI microsomal intrinsic clearance of quercetin...

  13. Antioxidant property of quercetin-Cr(III) complex: The role of Cr(III) ion

    NASA Astrophysics Data System (ADS)

    Chen, Weijun; Sun, Shaofang; cao, Wei; Liang, Yan; Song, Jirong

    2009-01-01

    Flavonoid-metal complex is reported to exhibit a higher antioxidant activity than parent flavonoid. In this paper, experimental and theoretical methods are applied to study the antioxidant properties of quercetin and quercetin-Cr(III) complex, to find out the antioxidant activity variation and the role of Cr(III) ion on the antioxidant activity of the complex. Bond dissociation energy (BDE) and ionization potential (IP) of quercetin and the complex are calculated at the B3LYP/6-311++G(2d,2p)//B3LYP/LANL2DZ level. The experimental results show that the complex has a higher DPPH radical scavenging activity than quercetin. The calculated results show that the complex displays lower BDE and IP than quercetin. The IP of the complex declines obviously, indicating that the Cr (III) ion has more impact on the electron donating ability than on the hydrogen atom transferring ability of the complex.

  14. The effect of quercetin dietary supplementation on meat oxidation processes and texture of fattening lambs.

    PubMed

    Andrés, S; Huerga, L; Mateo, J; Tejido, M L; Bodas, R; Morán, L; Prieto, N; Rotolo, L; Giráldez, F J

    2014-02-01

    Thirty two lambs were fed a total mixed ration (TMR) formulated either with palm oil (CTRL; 34 g palm oil kg(-1) TMR) or whole flaxseed (+FS, 85 g flaxseed kg(-1) TMR) alone or enriched with quercetin (+QCT, 34 g palm oil plus 2 g quercetin kg(-1) TMR; +FS+QCT, 85 g flaxseed plus 2 g quercetin kg(-1) TMR). Dietary flaxseed did not affect, in a significant manner, the lipid peroxidation of meat samples. Quercetin treatment reduced oxysterol content (P<0.05) after 7 days of refrigerated storage of fresh meat, but did not affect significantly (P>0.05) the level of lipid-derived volatiles in the headspace of the light-exposed stored cooked meat. Sensory evaluation showed flaxseed as being responsible for a negative effect on meat flavour, probably associated with a modification of the fatty acid profile whereas, unexpectedly, quercetin seemed to worsen meat tenderisation. PMID:24200574

  15. Quercetin-containing self-nanoemulsifying drug delivery system for improving oral bioavailability.

    PubMed

    Tran, Thanh Huyen; Guo, Yi; Song, Donghui; Bruno, Richard S; Lu, Xiuling

    2014-03-01

    Quercetin is a dietary flavonoid with potential chemoprotective effects, but has low bioavailability because of poor aqueous solubility and low intestinal absorption. A quercetin-containing self-nanoemulsifying drug delivery system (Q-SNEDDS) was developed to form oil-in-water nanoemulsions in situ for improving quercetin oral bioavailability. On the basis of the quercetin solubility, emulsifying ability, and stability after dispersion in an aqueous phase, an optimal SNEDDS consisting of castor oil, Tween® 80, Cremophor® RH 40, and PEG 400 (20:16:34:30, w/w) was identified. Upon mixing with water, Q-SNEDDS formed a nanoemulsion having a droplet size of 208.8 ± 4.5 nm and zeta potential of -26.3 ± 1.2 mV. The presence of Tween® 80 and PEG 400 increased quercetin solubility and maintained supersaturated quercetin concentrations (5 mg/mL) for >1 month. The optimized Q-SNEDDS significantly improved quercetin transport across a human colon carcinoma (Caco-2) cell monolayer. Fluorescence imaging demonstrated rapid absorption of the Q-SNEDDS within 40 min of oral ingestion. Following oral administration of Q-SNEDDS in rats (15 mg/kg), the area under the concentration curve and maximum concentration of plasma quercetin after 24 h increased by approximately twofold and threefold compared with the quercetin control suspension. These data suggest that this Q-SNEDDS formulation can enhance the solubility and oral bioavailability of quercetin for appropriate clinical application. PMID:24464737

  16. Evaluation of polyamidoamine dendrimers as potential carriers for quercetin, a versatile flavonoid.

    PubMed

    Madaan, Kanika; Lather, Viney; Pandita, Deepti

    2016-01-01

    The aim of the present research work was to investigate the potential of polyamidoamine (PAMAM) dendrimers as oral drug delivery carriers for quercetin, a Biopharmaceutical Classification System (BCS) class II molecule. The aqueous solubility of quercetin was investigated in different generations of dendrimers, i.e. G0, G1, G2 and G3, with varying concentrations (0.1, 0.5, 1, 2 and 4 µM). Then, it was successfully incorporated in PAMAM dendrimers and they were characterized for incorporation efficacy, nature of nanoformulations, size, size distribution, surface morphology and stability. In vitro release characteristics of quercetin from all quercetin-PAMAM complexes were studied at 37 °C in phosphate buffer saline (PBS; pH 7.4). Furthermore, the efficacy of quercetin-loaded PAMAM dendrimer was assessed by pharmacodynamic experiment, namely, a carrageenan-induced paw edema model to evaluate the acute activity of this nanocarrier in response to inflammation. It was observed that both generation and the respective concentrations of PAMAM dendrimers showed potential positive effects on solubility enhancement of quercetin. All the quercetin-PAMAM complexes were found to be in nanometeric range (<100 nm) with narrow polydispersity index. In vitro study revealed a biphasic release pattern of quercetin which was characterized by an initial faster release followed by sustained release phase and pharmacodynamic study provided the preliminary proof of concept about the potential of quercetin-PAMAM complexes. The study concludes that the dendrimer-based drug delivery system for quercetin has enormous potential to resolve the drug delivery issues associated with it. PMID:24845475

  17. Cancer

    MedlinePlus

    ... Leukemia Liver cancer Non-Hodgkin lymphoma Ovarian cancer Pancreatic cancer Testicular cancer Thyroid cancer Uterine cancer ... have any symptoms. In certain cancers, such as pancreatic cancer, symptoms often do not start until the disease ...

  18. Simultaneous ingestion of high-methoxy pectin from apple can enhance absorption of quercetin in human subjects.

    PubMed

    Nishijima, Tomohiko; Takida, Yoshiki; Saito, Yasuo; Ikeda, Takayuki; Iwai, Kunihisa

    2015-05-28

    Chronic ingestion of apple pectin has been shown to increase the absorption of quercetin in rats. The present study was designed to elucidate whether the simultaneous ingestion of quercetin with apple pectin could enhance the absorption of quercetin in humans, and the effects of dose dependency and degree of pectin methylation on quercetin absorption were also investigated. Healthy volunteers (n 19) received 200 ml of 0.5 mg/ml of quercetin drinks with or without 10 mg/ml of pectin each in a randomised cross-over design study with over 1-week intervals; urine samples from all the subjects were collected within 24 h after ingestion of the test drinks, and urinary deconjugated quercetin and its metabolites were determined using HPLC. The sum of urinary quercetin and its metabolites excreted was increased by 2.5-fold by the simultaneous ingestion of pectin. The metabolism of methylated quercetin (isorhamnetin and tamarixetin) was not affected by pectin ingestion. In six volunteers, who received quercetin drinks containing 0, 3 and 10 mg/ml of pectin, the sum of urinary quercetin and its metabolites excreted also increased in a pectin dose-dependent manner. Furthermore, the simultaneous ingestion of quercetin with low-methoxy and high-methoxy pectin, respectively, increased the sum of urinary excretion of quercetin and its metabolites by 1.69-fold and significantly by 2.13-fold compared with the ingestion of quercetin without pectin. These results elucidated that apple pectin immediately enhanced quercetin absorption in human subjects, and that its enhancing effect was dependent on the dose and degree of pectin methylation. The results also suggested that the viscosity of pectin may play a role in the enhancement of quercetin absorption. PMID:25865751

  19. Quercetin phospholipid complex significantly protects against oxidative injury in ARPE-19 cells associated with activation of Nrf2 pathway.

    PubMed

    Xu, Xin-Rong; Yu, Hai-Tao; Yang, Yan; Hang, Li; Yang, Xue-Wen; Ding, Shu-Hua

    2016-01-01

    Age-related macular degeneration (AMD) is a major cause of blindness worldwide. Oxidative stress plays a crucial role in the pathogenesis of dry AMD. Quercetin has potent anti-oxidative activities, but poor bioavailability limits its therapeutic application. Herein, we prepared the phospholipid complex of quercetin (quercetin-PC), characterized its structure by differential scanning calorimetry, infrared spectrum and x-ray diffraction. Quercetin-PC had equilibrium solubility of 38.36 and 1351.27μg/ml in water and chloroform, respectively, which was remarkably higher than those of quercetin alone. Then we established hydrogen peroxide (H2O2)-induced oxidative injury model in human ARPE-19 cells to examine the effects of quercetin-PC. Quercetin-PC, stronger than quercetin, promoted cell proliferation, and the proliferation rate was increased to be 78.89% when treated with Quercetin-PC at 400μM. Moreover, quercetin-PC effectively prevented ARPE-19 cells from apoptosis, and the apoptotic rate was reduced to be 3.1% when treated with Quercetin-PC at 200μM. In addition, quercetin-PC at 200μM significantly increased the activities of SOD, CAT and GSH-PX, and reduced the levels of reactive oxygen species and MDA in H2O2-treated ARPE-19 cells, but quercetin at 200μM failed to do so. Molecular examinations revealed that quercetin-PC at 200μM significantly activated Nrf2 nuclear translocation and significantly enhanced the expression of target genes HO-1, NQO-1 and GCL by different folds at both mRNA and protein levels. Our current data collectively indicated that quercetin-PC had stronger protective effects against oxidative-induced damages in ARPE-19 cells, which was associated with activation of Nrf2 pathway and its target genes implicated in antioxidant defense. PMID:26643168

  20. The differential NF-kB modulation by S-adenosyl-L-methionine, N-acetylcysteine and quercetin on the promotion stage of chemical hepatocarcinogenesis.

    PubMed

    García-Román, Rebeca; Salazar-González, Daniel; Rosas, Sandra; Arellanes-Robledo, Jaime; Beltrán-Ramírez, Olga; Fattel-Fazenda, Samia; Villa-Treviño, Saúl

    2008-04-01

    S-adenosylmethionine (SAM), N-acetylcysteine (NAC) and quercetin exhibit a chemoprotective effect. Likely this effect is mediated by counteracting, oxidative stress and NF-kB activation. To test this hypothesis F344 rats were subjected to hepatocarcinogenesis with or without antioxidants. NAC decreased foci in number and area, SAM and quercetin decreased area. Lipid-peroxidation was decreased by antioxidants, but only SAM increased glutathione. SAM, in its regulation from IKK downwards, abolished the NF-kB activation. NAC decreased IKK and IkB-a phosphorylation, and Rel-A/p65 and NF-kB binding, though the last two were affected with less intensity compared to the NF-kB inhibitor. Quercetin decreased Rel-A/p65, without modifying upstream signalling. Although all antioxidants inhibited oxidative stress as shown by reduction of lipid peroxidation, not all exerted the same effect on NF-kB signalling pathway and only SAM increased GSH. The mechanisms exerted by SAM in the reduction of foci makes this compound a potential liver cancer therapeutic agent. PMID:18404532

  1. Protective effects of onion-derived quercetin on glutamate-mediated hippocampal neuronal cell death

    PubMed Central

    Yang, Eun-Ju; Kim, Geum-Soog; Kim, Jeong Ah; Song, Kyung-Sik

    2013-01-01

    Background: Neurodegenerative diseases are characterized by progressive neuron degeneration in specific functional systems of the central or peripheral nervous system. This study investigated the protective effects of quercetin isolated from onion on neuronal cells and its protective mechanisms against glutamate-induced apoptosis in HT22 cells. Materials and Methods: HT22 cells were cultured to study the neuroprotective mechanism of quercetin against glutamate-mediated oxidative stress. The intracellular reactive oxygen species (ROS) level and mitochondrial membrane potential (ΔΨm) were measured. The protein expression of calpain, spectrin, Bcl-2, Bax, Bid, cytochrome c, and mitogen-activated protein kinases (MAPKs) was evaluated by Western blotting. Results: Quercetin had a protective effect by reducing both intracellular ROS overproduction and glutamate-mediated Ca2+ influx. These effects were due to the downregulation of several apoptosis-related biochemical markers. Calpain expression was reduced and spectrin cleavage was inhibited by quercetin in glutamate-exposed HT22 cells. Disruption of the mitochondrial membrane potential (ΔΨm), activation of the pro-apoptotic proteins Bid and Bax, and cytochrome c release in response to glutamate-induced oxidative stress were reduced. Quercetin also suppressed phosphorylation of MAPKs. Conclusion: This is the first report on the detailed mechanisms of the protective effect of quercetin on HT22 cells. Onion extract and quercetin may be useful for preventing or treating neurodegenerative disorders. PMID:24124281

  2. Quercetin-3-O-glucuronide induces ABCA1 expression by LXRα activation in murine macrophages

    SciTech Connect

    Ohara, Kazuaki; Wakabayashi, Hideyuki; Taniguchi, Yoshimasa; Shindo, Kazutoshi; Yajima, Hiroaki; Yoshida, Aruto

    2013-11-29

    Highlights: •The major circulating quercetin metabolite (Q3GA) activated LXRα. •Q3GA induced ABCA1 via LXRα activation in macrophages. •Nelumbo nucifera leaf extracts contained quercetin glycosides. •N. nucifera leaf extract feeding elevated HDLC in mice. -- Abstract: Reverse cholesterol transport (RCT) removes excess cholesterol from macrophages to prevent atherosclerosis. ATP-binding cassette, subfamily A, member 1 (ABCA1) is a crucial cholesterol transporter involved in RCT to produce high density lipoprotein-cholesterol (HDLC), and is transcriptionally regulated by liver X receptor alpha (LXRα), a nuclear receptor. Quercetin is a widely distributed flavonoid in edible plants which prevented atherosclerosis in an animal model. We found that quercetin-3-O-glucuronide (Q3GA), a major quercetin metabolite after absorption from the digestive tract, enhanced ABCA1 expression, in vitro, via LXRα in macrophages. In addition, leaf extracts of a traditional Asian edible plant, Nelumbo nucifera (NNE), which contained abundant amounts of quercetin glycosides, significantly elevated plasma HDLC in mice. We are the first to present experimental evidence that Q3GA induced ABCA1 in macrophages, and to provide an alternative explanation to previous studies on arteriosclerosis prevention by quercetin.

  3. Onion skin waste as a valorization resource for the by-products quercetin and biosugar.

    PubMed

    Choi, In Seong; Cho, Eun Jin; Moon, Jae-Hak; Bae, Hyeun-Jong

    2015-12-01

    Onion skin waste (OSW), which is produced from processed onions, is a major industrial waste. We evaluated the use of OSW for biosugar and quercetin production. The carbohydrate content of OSW was analyzed, and the optimal conversion conditions were evaluated by varying enzyme mixtures and loading volumes for biosugar production and quercetin extraction. The enzymatic conversion rate of OSW to biosugar was 98.5% at 0.72 mg of cellulase, 0.16 mg of pectinase, and 1.0mg of xylanase per gram of dry OSW. Quercetin extraction also increased by 1.61-fold after complete enzymatic hydrolysis. In addition, the newly developed nano-matrix (terpyridine-immobilized silica-coated magnetic nanoparticles-zinc (TSMNP-Zn matrix) was utilized to separate quercetin from OSW extracts. The nano-matrix facilitated easy separation and purification of quercetin. Using the TSMNP-Zn matrix the quercetin was approximately 90% absorbed. In addition, the recovery yield of quercetin was approximately 75% after treatment with ethylenediaminetetraacetic acid. PMID:26041228

  4. Extraction of quercetin from Herba Lysimachiae by molecularly imprinted-matrix solid phase dispersion.

    PubMed

    Hong, Yansuo; Chen, Ligang

    2013-12-15

    A new kind of quercetin molecularly imprinted polymer (MIP) was synthesized and applied as a selective sorbent in matrix solid-phase dispersion (MSPD) for the extraction of quercetin in Herba Lysimachiae. The MIP was prepared by surface imprinting method using quercetin as template, methacrylic acid as functional monomer, trimethylolpropane trimethacrylate as crosslinker and methanol as porogen. The selectivity of quercetin MIP was evaluated according to their recognition to quercetin and a compound with similar molecular size (bergenin). Good binding for quercetin was observed in MIP adsorption experiment. The isothermal adsorption and dynamic adsorption experiments were also carried out in this study. The best quercetin extraction conditions were as follows: the ratio of MIP to sample was 1:1, the dispersion time was 10min, washing solvent was 2% aqueous methanol and elution solvent was acetic acid-methanol (2:98, v/v). The proposed method was compared with the method used in Chinese pharmacopeia. The similar extraction yield was obtained by the two methods. Moreover, this method is faster, simpler and can realize extraction and purification procedures in the same system. PMID:24184834

  5. Quercetin Influences Quorum Sensing in Food Borne Bacteria: In-Vitro and In-Silico Evidence

    PubMed Central

    Gopu, Venkadesaperumal; Meena, Chetan Kumar; Shetty, Prathapkumar Halady

    2015-01-01

    Quorum sensing (QS) plays a vital role in regulating the virulence factor of many food borne pathogens, which causes severe public health risk. Therefore, interrupting the QS signaling pathway may be an attractive strategy to combat microbial infections. In the current study QS inhibitory activity of quercetin and its anti-biofilm property was assessed against food-borne pathogens using a bio-sensor strain. In addition in-silico techniques like molecular docking and molecular dynamics simulation studies were applied to screen the quercetin’s potentiality as QS inhibitor. Quercetin (80μg/ml) showed the significant reduction in QS-dependent phenotypes like violacein production, biofilm formation, exopolysaccharide (EPS) production, motility and alginate production in a concentration-dependent manner. Synergistic activity of conventional antibiotics with quercetin enhanced the susceptibility of all tested pathogens. Furthermore, Molecular docking analysis revealed that quercetin binds more rigidly with LasR receptor protein than the signaling compound with docking score of -9.17Kcal/mol. Molecular dynamics simulation predicted that QS inhibitory activity of quercetin occurs through the conformational changes between the receptor and quercetin complex. Above findings suggest that quercetin can act as a competitive inhibitor for signaling compound towards LasR receptor pathway and can serve as a novel QS-based antibacterial/anti-biofilm drug to manage food-borne pathogens. PMID:26248208

  6. The effects of quercetin dietary supplementation on broiler growth performance, meat quality, and oxidative stability.

    PubMed

    Goliomytis, M; Tsoureki, D; Simitzis, P E; Charismiadou, M A; Hager-Theodorides, A L; Deligeorgis, S G

    2014-08-01

    The present study was conducted to describe the effects of quercetin dietary supplementation, at levels of 0.5 and 1 g/kg of feed, on growth performance, internal organ weights, meat quality, and meat oxidative stability during storage of broiler chickens reared from hatching to 42 d of age. Body weight and cumulative feed intake were not affected by quercetin supplementation (P > 0.05). However, poorer feed conversion ratio values were obtained with increasing levels of dietary quercetin (P-linear < 0.05). Relative heart weight was significantly higher for chickens that were given quercetin in comparison with the controls (P < 0.05). The rest of the internal organ weights measured (liver, spleen, and fat pad) and meat quality traits were not affected by dietary supplementation with quercetin, except for meat lightness and redness. Meat oxidative stability, expressed as nanograms of malondialdehyde per gram of meat, was improved (P < 0.05) during refrigerated storage for 3 and 9 d, when birds were fed quercetin at a level of 1 g/kg of feed. It is concluded that the incorporation of quercetin in broiler diets could prolong meat shelf life by reducing the rate of lipid oxidation, and increase relative heart weight, potentially contributing to improved animal health. PMID:24894531

  7. Quercetin supplementation does not enhance cerebellar mitochondrial biogenesis and oxidative status in exercised rats.

    PubMed

    Casuso, Rafael A; Martínez-Amat, Antonio; Hita-Contreras, Fidel; Camiletti-Moirón, Daniel; Aranda, Pilar; Martínez-López, Emilio

    2015-07-01

    The present study tested the hypothesis that quercetin may inhibit the mitochondrial and antioxidant adaptations induced by exercise in cerebellar tissue. Thirty-five 6-week-old Wistar rats were randomly allocated into the following groups: quercetin, exercised (Q-Ex; n = 9); quercetin, sedentary (Q-Sed; n = 9); no quercetin, exercised (NQ-Ex; n = 9); and no quercetin, sedentary (NQ-Sed; n = 8). After 6 weeks of quercetin supplementation and/or exercise training, cerebellums were collected. Protein carbonyl content (PCC), sirtuin 1, peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), messenger RNA levels, citrate synthase (CS), and mitochondrial DNA were measured. When Q-Sed was compared with NQ-Sed, PCC (P < .005) showed decreased levels, whereas PGC-1α, sirtuin 1 (both, P < .01), mitochondrial DNA (P < .001), and CS (P < .01) increased. However, when Q-Ex was compared with Q-Sed, PCC showed increased levels (P < .001), whereas CS decreased (P < .01). Furthermore, the NQ-Ex group experienced an increase in PGC-1α messenger RNA levels in comparison with NQ-Sed (P > .01). This effect, however, did not appear in Q-Ex (P < .05). Therefore, we must hypothesize that either the dose (25 mg/kg) or the length of the quercetin supplementation period that was used in the present study (or perhaps both) may impair exercise-induced adaptations in cerebellar tissue. PMID:26032482

  8. Effect of Quercetin on Hepatitis C Virus Life Cycle: From Viral to Host Targets.

    PubMed

    Rojas, Ángela; Del Campo, Jose A; Clement, Sophie; Lemasson, Matthieu; García-Valdecasas, Marta; Gil-Gómez, Antonio; Ranchal, Isidora; Bartosch, Birke; Bautista, Juan D; Rosenberg, Arielle R; Negro, Francesco; Romero-Gómez, Manuel

    2016-01-01

    Quercetin is a natural flavonoid, which has been shown to have anti hepatitis C virus (HCV) properties. However, the exact mechanisms whereby quercetin impacts the HCV life cycle are not fully understood. We assessed the effect of quercetin on different steps of the HCV life cycle in Huh-7.5 cells and primary human hepatocytes (PHH) infected with HCVcc. In both cell types, quercetin significantly decreased i) the viral genome replication; ii) the production of infectious HCV particles and iii) the specific infectivity of the newly produced viral particles (by 85% and 92%, Huh7.5 and PHH respectively). In addition, when applied directly on HCV particles, quercetin reduced their infectivity by 65%, suggesting that it affects the virion integrity. Interestingly, the HCV-induced up-regulation of diacylglycerol acyltransferase (DGAT) and the typical localization of the HCV core protein to the surface of lipid droplets, known to be mediated by DGAT, were both prevented by quercetin. In conclusion, quercetin appears to have direct and host-mediated antiviral effects against HCV. PMID:27546480

  9. Effect of Quercetin on Hepatitis C Virus Life Cycle: From Viral to Host Targets

    PubMed Central

    Rojas, Ángela; Del Campo, Jose A.; Clement, Sophie; Lemasson, Matthieu; García-Valdecasas, Marta; Gil-Gómez, Antonio; Ranchal, Isidora; Bartosch, Birke; Bautista, Juan D.; Rosenberg, Arielle R.; Negro, Francesco; Romero-Gómez, Manuel

    2016-01-01

    Quercetin is a natural flavonoid, which has been shown to have anti hepatitis C virus (HCV) properties. However, the exact mechanisms whereby quercetin impacts the HCV life cycle are not fully understood. We assessed the effect of quercetin on different steps of the HCV life cycle in Huh-7.5 cells and primary human hepatocytes (PHH) infected with HCVcc. In both cell types, quercetin significantly decreased i) the viral genome replication; ii) the production of infectious HCV particles and iii) the specific infectivity of the newly produced viral particles (by 85% and 92%, Huh7.5 and PHH respectively). In addition, when applied directly on HCV particles, quercetin reduced their infectivity by 65%, suggesting that it affects the virion integrity. Interestingly, the HCV-induced up-regulation of diacylglycerol acyltransferase (DGAT) and the typical localization of the HCV core protein to the surface of lipid droplets, known to be mediated by DGAT, were both prevented by quercetin. In conclusion, quercetin appears to have direct and host-mediated antiviral effects against HCV. PMID:27546480

  10. New Approach for Treatment of Primary Liver Tumors: The Role of Quercetin.

    PubMed

    Brito, Ana Filipa; Ribeiro, Marina; Abrantes, Ana Margarida; Mamede, Ana Catarina; Laranjo, Mafalda; Casalta-Lopes, João Eduardo; Gonçalves, Ana Cristina; Sarmento-Ribeiro, Ana Bela; Tralhão, José Guilherme; Botelho, Maria Filomena

    2016-01-01

    Hepatocellular carcinoma (HCC) is the most common primary liver tumor (PLT), with cholangiocarcinoma (CC) being the second most frequent. Glucose transporter 1 (GLUT-1) expression is increased in PLTs and therefore it is suggested as a therapeutic target. Flavonoids, like quercetin, are GLUT-1 competitive inhibitors and may be considered as potential therapeutic agents for PLTs. The objective of this study was evaluation of quercetin anticancer activity in three human HCC cell lines (HepG2, HuH7, and Hep3B2.1-7) and in a human CC cell line (TFK-1). The possible synergistic effect between quercetin and sorafenib, a nonspecific multikinase inhibitor used in clinical practice in patients with advanced HCC, was also evaluated. It was found that in all the cell lines, quercetin induced inhibition of the metabolic activity and cell death by apoptosis, followed by increase in BAX/BCL-2 ratio. Treatment with quercetin caused DNA damage in HepG2, Hep3B2.1-7, and TFK-1 cell lines. The effect of quercetin appears to be independent of P53. Incubation with quercetin induced an increase in GLUT-1 membrane expression and a consequent reduction in the cytoplasmic fraction, observed as a decrease in (18)F-FDG uptake, indicating a GLUT-1 competitive inhibition. The occurrence of synergy when sorafenib and quercetin were added simultaneously to HCC cell lines was noticed. Thus, the use of quercetin seems to be a promising approach for PLTs through GLUT-1 competitive inhibition. PMID:26943884

  11. Quercetin inhibits intestinal iron absorption and ferroportin transporter expression in vivo and in vitro.

    PubMed

    Lesjak, Marija; Hoque, Rukshana; Balesaria, Sara; Skinner, Vernon; Debnam, Edward S; Srai, Surjit K S; Sharp, Paul A

    2014-01-01

    Balancing systemic iron levels within narrow limits is critical for maintaining human health. There are no known pathways to eliminate excess iron from the body and therefore iron homeostasis is maintained by modifying dietary absorption so that it matches daily obligatory losses. Several dietary factors can modify iron absorption. Polyphenols are plentiful in human diet and many compounds, including quercetin--the most abundant dietary polyphenol--are potent iron chelators. The aim of this study was to investigate the acute and longer-term effects of quercetin on intestinal iron metabolism. Acute exposure of rat duodenal mucosa to quercetin increased apical iron uptake but decreased subsequent basolateral iron efflux into the circulation. Quercetin binds iron between its 3-hydroxyl and 4-carbonyl groups and methylation of the 3-hydroxyl group negated both the increase in apical uptake and the inhibition of basolateral iron release, suggesting that the acute effects of quercetin on iron transport were due to iron chelation. In longer-term studies, rats were administered quercetin by a single gavage and iron transporter expression measured 18 h later. Duodenal FPN expression was decreased in quercetin-treated rats. This effect was recapitulated in Caco-2 cells exposed to quercetin for 18 h. Reporter assays in Caco-2 cells indicated that repression of FPN by quercetin was not a transcriptional event but might be mediated by miRNA interaction with the FPN 3'UTR. Our study highlights a novel mechanism for the regulation of iron bioavailability by dietary polyphenols. Potentially, diets rich in polyphenols might be beneficial for patients groups at risk of iron loading by limiting the rate of intestinal iron absorption. PMID:25058155

  12. Quercetin, a potent suppressor of NF-κB and Smad activation in osteoblasts.

    PubMed

    Yamaguchi, Masayoshi; Weitzmann, M Neale

    2011-10-01

    Osteoclasts, the bone resorbing cells of the body, form when osteoclast precursors are exposed to the key osteoclastogenic cytokine receptor activator of NF-κB ligand (RANKL), a process requiring induction of NF-κB signaling. Quercetin is a ubiquitous plant-derived flavonoid with well documented anti-inflammatory properties, in part, a consequence of its capacity to downmodulate the NF-κB signal transduction pathway. Consistent with this mechanism of action quercetin is reported to suppress osteoclastogenesis in vitro and prevent bone loss in ovariectomized mice in vivo. By contrast, the effect of quercetin on osteoblasts, the cells responsible for bone formation, is contradictory with conflicting reports of inhibition as well as stimulation. Given our previous reports that NF-κB antagonists promote osteoblast differentiation and activity, we compared the effects of quercetin on osteoclast and osteoblast differentiation and on NF-κB signal transduction in vitro. As expected, quercetin potently suppressed osteoclastogenesis and NF-κB activation induced by RANKL in osteoclast precursors. However, the same doses of quercetin had no effect on osteoblast mineralization, and failed to significantly alleviate the inhibitory effect of NF-κB-induced by TNFα, even though quercetin potently suppressed NF-κB activation in these cells. This apparent contradiction was explained by the fact that addition to its anti-NF-κB activity, quercetin also potently antagonized both TGFβ and BMP-2-induced Smad activation in osteoblast precursors. Taken together our data suggest that multiple competing actions of quercetin mediate both stimulatory and inhibitory actions on osteoblasts with the final physiological effect likely a function of the net balance between these stimulatory and inhibitory effects. PMID:21769418

  13. Dietary quercetin inhibits bone loss without effect on the uterus in ovariectomized mice.

    PubMed

    Tsuji, Mitsuyoshi; Yamamoto, Hironori; Sato, Tadatoshi; Mizuha, Yoko; Kawai, Yoshichika; Taketani, Yutaka; Kato, Shigeaki; Terao, Junji; Inakuma, Takahiro; Takeda, Eiji

    2009-01-01

    Quercetin is a major dietary flavonoid found in onions and other vegetables, and potentially has beneficial effects on disease prevention. In the present study, we demonstrate for the first time the effects of dietary quercetin on bone loss and uterine weight loss by ovariectomy in vivo. Female mice were ovariectomized (OVX) and were randomly allocated to 3 groups: a control diet or a diet with 0.25% (LQ) or 2.5% quercetin (HQ). After 4 weeks, dietary quercetin had no effects on uterine weight in OVX mice, but bone mineral density of the lumbar spine L4 and femur measured by peripheral quantitative computed tomography (pQCT) was higher in both the sham and the HQ groups than in the OVX group. Histomorphometric analysis showed that the HQ group restored bone volume (BV/TV) completely in distal femoral cancellous bone, but did not reduce the osteoclast surface area and osteoclast number when compared with the OVX group. In in-vitro experiments using mouse monocyte/macrophage cell line RAW264.7 cells, however, quercetin and its conjugate, quercetin-3-O-beta-D: -glucuronide dose-dependently inhibited the receptor activator of nuclear factor-kappa B ligand (RANKL)-induced osteoclast differentiation, and the RANKL-stimulated expression of osteoclast related genes was also inhibited by quercetin. The luciferase reporter assay showed that quercetin did not appear to have estrogenic activity through estrogen receptors. These results suggest that dietary quercetin inhibits bone loss without effect on the uterus in OVX mice and does not act as a potent inhibitor of osteoclastogenesis or as a selective estrogen receptor modulator in vivo. PMID:19495926

  14. Whole-epigenome analysis in multiple myeloma reveals DNA hypermethylation of B cell-specific enhancers

    PubMed Central

    Castellano, Giancarlo; Pascual, Marien; Heath, Simon; Kulis, Marta; Segura, Victor; Bergmann, Anke; Esteve, Anna; Merkel, Angelika; Raineri, Emanuele; Agueda, Lidia; Blanc, Julie; Richardson, David; Clarke, Laura; Datta, Avik; Russiñol, Nuria; Queirós, Ana C.; Beekman, Renée; Rodríguez-Madoz, Juan R.; José-Enériz, Edurne San; Fang, Fang; Gutiérrez, Norma C.; García-Verdugo, José M.; Robson, Michael I.; Schirmer, Eric C.; Guruceaga, Elisabeth; Martens, Joost H.A.; Gut, Marta; Calasanz, Maria J.; Flicek, Paul; Siebert, Reiner; Campo, Elías; Miguel, Jesús F. San; Melnick, Ari; Stunnenberg, Hendrik G.; Gut, Ivo G.

    2015-01-01

    While analyzing the DNA methylome of multiple myeloma (MM), a plasma cell neoplasm, by whole-genome bisulfite sequencing and high-density arrays, we observed a highly heterogeneous pattern globally characterized by regional DNA hypermethylation embedded in extensive hypomethylation. In contrast to the widely reported DNA hypermethylation of promoter-associated CpG islands (CGIs) in cancer, hypermethylated sites in MM, as opposed to normal plasma cells, were located outside CpG islands and were unexpectedly associated with intronic enhancer regions defined in normal B cells and plasma cells. Both RNA-seq and in vitro reporter assays indicated that enhancer hypermethylation is globally associated with down-regulation of its host genes. ChIP-seq and DNase-seq further revealed that DNA hypermethylation in these regions is related to enhancer decommissioning. Hypermethylated enhancer regions overlapped with binding sites of B cell-specific transcription factors (TFs) and the degree of enhancer methylation inversely correlated with expression levels of these TFs in MM. Furthermore, hypermethylated regions in MM were methylated in stem cells and gradually became demethylated during normal B-cell differentiation, suggesting that MM cells either reacquire epigenetic features of undifferentiated cells or maintain an epigenetic signature of a putative myeloma stem cell progenitor. Overall, we have identified DNA hypermethylation of developmentally regulated enhancers as a new type of epigenetic modification associated with the pathogenesis of MM. PMID:25644835

  15. The Role of Mast Cell Specific Chymases and Tryptases in Tumor Angiogenesis

    PubMed Central

    de Souza Junior, Devandir Antonio; Santana, Ana Carolina; da Silva, Elaine Zayas Marcelino; Oliver, Constance; Jamur, Maria Celia

    2015-01-01

    An association between mast cells and tumor angiogenesis is known to exist, but the exact role that mast cells play in this process is still unclear. It is thought that the mediators released by mast cells are important in neovascularization. However, it is not known how individual mediators are involved in this process. The major constituents of mast cell secretory granules are the mast cell specific proteases chymase, tryptase, and carboxypeptidase A3. Several previous studies aimed to understand the way in which specific mast cell granule constituents act to induce tumor angiogenesis. A body of evidence indicates that mast cell proteases are the pivotal players in inducing tumor angiogenesis. In this review, the likely mechanisms by which tryptase and chymase can act directly or indirectly to induce tumor angiogenesis are discussed. Finally, information presented here in this review indicates that mast cell proteases significantly influence angiogenesis thus affecting tumor growth and progression. This also suggests that these proteases could serve as novel therapeutic targets for the treatment of various types of cancer. PMID:26146612

  16. Editing T cell specificity towards leukemia by zinc-finger nucleases and lentiviral gene transfer

    PubMed Central

    Lombardo, Angelo; Magnani, Zulma; Liu, Pei-Qi; Reik, Andreas; Chu, Victoria; Paschon, David E.; Zhang, Lei; Kuball, Jurgen; Camisa, Barbara; Bondanza, Attilio; Casorati, Giulia; Ponzoni, Maurilio; Ciceri, Fabio; Bordignon, Claudio; Greenberg, Philip D.; Holmes, Michael C.; Gregory, Philip D.; Naldini, Luigi; Bonini, Chiara

    2016-01-01

    The transfer of high-avidity T-cell receptor (TCR) genes isolated from rare tumor-specific lymphocytes into polyclonal T cells is an attractive cancer immunotherapy strategy. However, TCR gene transfer results in competition for surface expression and inappropriate pairing between the exogenous and endogenous TCR chains, resulting in suboptimal activity and potentially harmful unpredicted specificities. We designed zinc-finger nucleases (ZFNs) promoting the disruption of endogenous TCR β and α chain genes. ZFN-treated lymphocytes lacked CD3/TCR surface expression and expanded with IL-7 and IL-15. Upon lentiviral transfer of a TCR for the WT1 tumor antigen, these TCR-edited cells expressed the new TCR at high levels, were easily expanded to near-purity, and proved superior in specific antigen recognition to matched TCR-transferred cells. In contrast to TCR-transferred cells, TCR edited lymphocytes did not mediate off-target reactivity while maintaining anti-tumor activity in vivo, thus demonstrating that complete editing of T-cell specificity generate tumor-specific lymphocytes with improved biosafety profile. PMID:22466705

  17. Antiatherogenic Roles of Dietary Flavonoids Chrysin, Quercetin, and Luteolin.

    PubMed

    Basu, Anandita; Das, Anindhya S; Majumder, Munmi; Mukhopadhyay, Rupak

    2016-07-01

    Cardiovascular diseases (CVDs) are the commonest cause of global mortality and morbidity. Atherosclerosis, the fundamental pathological manifestation of CVDs, is a complex process and is poorly managed both in terms of preventive and therapeutic intervention. Aberrant lipid metabolism and chronic inflammation play critical roles in the development of atherosclerosis. These processes can be targeted for effective management of the disease. Although managing lipid metabolism is in the forefront of current therapeutic approaches, controlling inflammation may also prove to be crucial for an efficient treatment regimen of the disease. Flavonoids, the plant-derived polyphenols, are known for their antiinflammatory properties. This review discusses the possible antiatherogenic role of 3 flavonoids, namely, chrysin, quercetin, and luteolin primarily known for their antiinflammatory properties. PMID:27385185

  18. Cell-Specific Radiosensitization by Gold Nanoparticles at Megavoltage Radiation Energies

    SciTech Connect

    Jain, Suneil; Coulter, Jonathan A.; Hounsell, Alan R.; Butterworth, Karl T.; McMahon, Stephen J.; Hyland, Wendy B.; Muir, Mark F.; Dickson, Glenn R.; Prise, Kevin M.; Currell, Fred J.; O'Sullivan, Joe M.; Hirst, David G.

    2011-02-01

    Purpose: Gold nanoparticles (GNPs) have been shown to cause sensitization with kilovoltage (kV) radiation. Differences in the absorption coefficient between gold and soft tissue, as a function of photon energy, predict that maximum enhancement should occur in the kilovoltage (kV) range, with almost no enhancement at megavoltage (MV) energies. Recent studies have shown that GNPs are not biologically inert, causing oxidative stress and even cell death, suggesting a possible biological mechanism for sensitization. The purpose of this study was to assess GNP radiosensitization at clinically relevant MV X-ray energies. Methods and Materials: Cellular uptake, intracellular localization, and cytotoxicity of GNPs were assessed in normal L132, prostate cancer DU145, and breast cancer MDA-MB-231 cells. Radiosensitization was measured by clonogenic survival at kV and MV photon energies and MV electron energies. Intracellular DNA double-strand break (DSB) induction and DNA repair were determined and GNP chemosensitization was assessed using the radiomimetic agent bleomycin. Results: GNP uptake occurred in all cell lines and was greatest in MDA-MB-231 cells with nanoparticles accumulating in cytoplasmic lysosomes. In MDA-MB-231 cells, radiation sensitizer enhancement ratios (SERs) of 1.41, 1.29, and 1.16 were achieved using 160 kVp, 6 MV, and 15 MV X-ray energies, respectively. No significant effect was observed in L132 or DU145 cells at kV or MV energies (SER 0.97-1.08). GNP exposure did not increase radiation-induced DSB formation or inhibit DNA repair; however, GNP chemosensitization was observed in MDA-MB-231 cells treated with bleomycin (SER 1.38). Conclusions: We have demonstrated radiosensitization in MDA-MB-231 cells at MV X-ray energies. The sensitization was cell-specific with comparable effects at kV and MV energies, no increase in DSB formation, and GNP chemopotentiation with bleomycin, suggesting a possible biological mechanism of radiosensitization.

  19. Quercetin derivatives as novel antihypertensive agents: Synthesis and physiological characterization.

    PubMed

    Grande, Fedora; Parisi, Ortensia I; Mordocco, Roberta A; Rocca, Carmine; Puoci, Francesco; Scrivano, Luca; Quintieri, Anna M; Cantafio, Patrizia; Ferla, Salvatore; Brancale, Andrea; Saturnino, Carmela; Cerra, Maria C; Sinicropi, Maria S; Angelone, Tommaso

    2016-01-20

    The antihypertensive flavonol quercetin (Q1) is endowed with a cardioprotective effect against myocardial ischemic damage. Q1 inhibits angiotensin converting enzyme activity, improves vascular relaxation, and decreases oxidative stress and gene expression. However, the clinical application of this flavonol is limited by its poor bioavailability and low stability in aqueous medium. In the aim to overcome these drawbacks and preserve the cardioprotective effects of quercetin, the present study reports on the preparation of five different Q1 analogs, in which all OH groups were replaced by hydrophobic functional moieties. Q1 derivatives have been synthesized by optimizing previously reported procedures and analyzed by spectroscopic analysis. The cardiovascular properties of the obtained compounds were also investigated in order to evaluate whether chemical modification affects their biological efficacy. The interaction with β-adrenergic receptors was evaluated by molecular docking and the cardiovascular efficacy was investigated on the ex vivo Langendorff perfused rat heart. Furthermore, the bioavailability and the antihypertensive properties of the most active derivative were evaluated by in vitro studies and in vivo administration (1month) on spontaneously hypertensive rats (SHRs), respectively. Among all studied Q1 derivatives, only the ethyl derivative reduced left ventricular pressure (at 10(-8)M÷10(-6)M doses) and improved relaxation and coronary dilation. NOSs inhibition by L-NAME abolished inotropism, lusitropism and coronary effects. Chronic administration of high doses of this compound on SHR reduced systolic and diastolic pressure. Differently, the acetyl derivative induced negative inotropism and lusitropism (at 10(-10)M and 10(-8)÷10(-6)M doses), without affecting coronary pressure. Accordingly, docking studies suggested that these compounds bind both β1/β2-adrenergic receptors. Taking into consideration all the obtained results, the replacement of

  20. Viscum album L. extract and quercetin reduce cyclophosphamide-induced cardiotoxicity, urotoxicity and genotoxicity in mice.

    PubMed

    Sekeroğlu, Vedat; Aydin, Birsen; Sekeroğlu, Zülal Atli

    2011-01-01

    Possible protective effects of a methanolic extract of Viscum album (VA) and quercetin (QE) against cyclophosphamide (CP) induced cardiotoxicity, urotoxicity and genotoxicity in mice were evaluated. Mice were administered orally VA (250 mg/kg/day) and QE (50 mg/kg/day) for 10 days alone or in combination with CP. After the same doses of VA and QE given for 7 days, rats were intraperitoneally administered CP (40 mg/kg) on days 8 and 9 of the experiment. Cardiotoxic, urotoxic and genotoxic effects were examined in serum, heart, bladder and bone marrow. Significant decreases in the levels of antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase), glutathione-S-transferases, reduced glutathione and mitotic index were observed. QE completely and VA partly ameliorated almost of all the examined parameters when given together with CP. Higher total nitrate/nitrite levels were observed in the myocardial tissue treated with QE and VA in combination with CP. In addition, the pre-treatment with VA and QE together with CP significantly decreased chromosome aberrations and aberrant cells compared to CP alone. Results from the current study suggest that QE and VA supplementation attenuates CP induced cardiotoxicity, urotoxicity and genotoxicity through a mechanism related to their ability to decrease oxidative stress and inflammation, and at least in part to its protective effects on the cardiovascular system. In addition, VA and QE may play a role in reducing cytogenotoxicity induced by anti-neoplastic drugs during cancer chemotherapy. PMID:22393965

  1. Mapping the interactions and bioactivity of quercetin-(2-hydroxypropyl)-β-cyclodextrin complex.

    PubMed

    Kellici, Tahsin F; Chatziathanasiadou, Maria V; Diamantis, Dimitris; Chatzikonstantinou, Alexandra V; Andreadelis, Ioannis; Christodoulou, Eirini; Valsami, Georgia; Mavromoustakos, Thomas; Tzakos, Andreas G

    2016-09-10

    Natural products have served as a rich source for drug discovery and development. In the last decade their fruitful integration in the drug discovery pipeline declined due to their reduced bioavailability, mainly attributed to their poor aqueous solubility. We synthesized a quercetin (QUE)-(2-hydroxypropyl)-β-cyclodextrin (HP-β-CD) complex that enabled amplification of its solubility and in the same time retained its bioactivity in T24 human bladder cancer cell line. The stability of the complex and the molecular basis of the interactions developed in this host-guest complex were assayed by incorporating an array of analytical techniques and Molecular Dynamics (MD) experiments. 2D DOSY NMR experiment revealed that the diffusion coefficient of free HP-β-CD was 3.55×10(-10)m(2)s(-1) while that of QUE-HP-β-CD inclusion complex 3.09×10(-10)m(2)s(-1), indicating the formation of a complex. Solid and liquid high resolution NMR spectroscopy data showed that the most pronounced differences in chemical shifts at carbons and protons correspondingly during complexation occur in the aromatic ring Α (bearing the two phenolic hydroxyl groups meta to each other). The chemical shift differences in the aromatic ring Β (bearing the two phenolic hydroxyl groups ortho to each other) were less pronounced. The MD results confirmed the experimental data. PMID:27395802

  2. Quercetin induces apoptosis and enhances 5-FU therapeutic efficacy in hepatocellular carcinoma.

    PubMed

    Dai, Wei; Gao, Quangen; Qiu, Jianping; Yuan, Jianmao; Wu, Guoliang; Shen, Genhai

    2016-05-01

    Quercetin (Q), a flavonoid compound, which is obtained in variety of fruits, seeds, and vegetables, has been reported to possess many pharmacological properties including cancer-preventive and anticancer effects. However, studies on the anticancer effects and underlying mechanisms of Q in human hepatocellular carcinoma (HCC) are still limited. The present study is conducted to investigate the anticancer efficacy and adjuvant chemotherapy action of Q in HCC. HCC cell lines HepG2 and SMCC-7721 were treated with different concentrations of Q. The antiproliferative effects of Q were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), and the apoptosis and cell cycle dynamics were assessed by flow cytometry; the expression of apoptosis-associated proteins were evaluated by Western blot and immunohistochemistry staining; the tumor growth in vivo was evaluated in a xenograft mouse model. Our results showed that Q effectively inhibited human HCC cell proliferation and induced apoptosis by upregulating the expression of Bad and Bax and downregulating the expression of Bcl-2 and Survivin in vitro. Furthermore, Q obviously inhibited the tumor growth and enhanced the 5-fluorouracil (5-FU) therapeutic efficacy in vitro and in vivo. Taken together, our findings highlight that Q effectively inhibited the growth of tumor and enhanced the sensitivity to thermotherapy, indicating Q is a potential treatment option for HCC. PMID:26628295

  3. Ameliorative Effect of Quercetin on Neurochemical and Behavioral Deficits in Rotenone Rat Model of Parkinson's Disease: Modulating Autophagy (Quercetin on Experimental Parkinson's Disease).

    PubMed

    El-Horany, Hemat E; El-Latif, Rania N Abd; ElBatsh, Maha M; Emam, Marwa N

    2016-07-01

    Autophagy is necessary for neuronal homeostasis and its dysfunction has been implicated in Parkinson's disease (PD) as it can exacerbate endoplasmic reticulum (ER) stress and ER stress-induced apoptosis. Quercetin is a flavonoid known for its neuroprotective and antioxidant effects. The present study investigated the protective, autophagy-modulating effects of quercetin in the rotenone rat model of PD. Rotenone was intraperitoneally injected at dose of 2 ml/kg/day for 4 weeks. Simultaneous intraperitoneal injection of quercetin was given at a dose of 50 mg/kg/day also for 4 weeks. Neurobehavioral changes were studied. Oxidative/antioxidant status, C/EBP homologous protein (CHOP), Beclin-1, and dopamine levels were assessed. DNA fragmentation and histopathological changes were evaluated. This research work revealed that quercetin significantly attenuated rotenone-induced behavioral impairment, augmented autophagy, ameliorated ER stress- induced apoptosis with attenuated oxidative stress. From the current study, quercetin can act as an autophagy enhancer in PD rat model and modulates the microenvironment that leads to neuronal death. PMID:27252111

  4. Role of quercetin as an alternative for obesity treatment: you are what you eat!

    PubMed

    Nabavi, Seyed Fazel; Russo, Gian Luigi; Daglia, Maria; Nabavi, Seyed Mohammad

    2015-07-15

    Obesity is one of the most serious global health problems, which increases the risk of other different chronic diseases. The crucial role of oxidative stress in the initiation and progression of obesity leads to the hypothesis that antioxidants can be used as therapeutic agents for obesity treatment. Among antioxidants, much attention has been paid to polyphenols due to their negligible adverse effects. Among them, quercetin is one of the most common dietary antioxidants widely distributed in different plant materials, such as fruits, vegetables and cereals. Quercetin shows a wide range of biological and health-promoting effects, such as anticancer, hepatoprotective, antidiabetic, anti-inflammatory and antibacterial activities. Furthermore, quercetin has anti-obesity activity through mitogen-activated protein kinase and adenine monophosphate-activated protein kinase signaling pathways. In this study, we reviewed the available scientific reports concerning the beneficial role of quercetin against obesity with emphasis on its mechanisms of action. PMID:25722169

  5. Effect of quercetine on survival and morphological properties of cultured embryonic rat spinal motoneurones.

    PubMed

    Ternaux, Jean-Pierre; Portalier, Paule

    2002-10-25

    Quercetine a flavonoid compound present in many plants and in the extract of Ginkgo biloba was shown to enhance the survival of purified rat spinal embryonic motoneurones, sampled at day embryonic 15 and maintained in culture for several days. Survival of embryonic spinal motoneurones is dose dependent and concentrations of quercetine ranging from 1 to 10 microM increase by 25% the number of living motoneurones in the culture. Excepted a slight significant decrease in the number of branches at day 3 and a small reduction of total neuritic length, no drastic changes in the motoneurones morphologies were observed in presence of quercetine. Results are discussed in term of neuronal protective effect of quercetine. PMID:12377378

  6. Quercetin does not alter the oral bioavailability of Atorvastatin in rats.

    PubMed

    Koritala, Rekha; Challa, Siva Reddy; Ragam, Satheesh Kumar; Geddam, Lal Babu; Venkatesh Reddy Challa, Venkatesh Reddy; Devi, Renuka; Sattenapalli, Srinu; Babu, Narendra

    2015-09-01

    The study was undertaken to evaluate the effect of Quercetin on the pharmacokinetics of Atorvastatin Calcium. In-vivo Pharmacokinetic studies were performed on rats in a single dose study and multiple dose study. Rats were treated with Quercetin (10 mg/kg) and Atorvastatin Calcium (20 mg/kg) orally and blood samples were collected at (0) pretreatment and 0.5, 1, 1.5, 2, 2.5, 3, 4, 8, 12, 24 hours post treatment. Plasma concentrations of Atorvastatin were estimated by HPLC method. Quercetin treatment did not significantly alter the pharmacokinetic parameters of atorvastatin like AUC(0-24), AUC(0-α) , T(max), C(max) and T(½) in both single dose and multiple dose studies of Atorvastatin Calcium. Quercetin does not alter the oral bioavailability of Atorvastatin Calcium in rats. PMID:26408869

  7. Exploration of the kinetic and thermochemical abilities for the free radical scavenging of two quercetin conformers

    NASA Astrophysics Data System (ADS)

    Mendoza-Wilson, Ana María; Sotelo-Mundo, Rogerio R.; Balandrán-Quintana, René R.; Glossman-Mitnik, Daniel; Sántiz-gómez, Marco a.; García-orozco, karina D.

    2010-09-01

    Quercetin has a great antioxidant potential due to its large capacity for free radical scavenging. Although it has been found that conformational changes have a profound effect on its chemical properties, there are few studies where conformation is associated with the antioxidant activity. The aim of this investigation was to explore the kinetic and the thermochemical abilities of two quercetin conformers for the free radical scavenging. Quercetin unhydrate (QUH) and quercetin dihydrate (QDH) conformers were studied employing 2,2-diphenyl-1-picrylhydrazyl (DPPH rad ) as in vitro radical model, and catechol and 4-hexyl-resorcinol as reference systems, for identifying the oxidation products. QDH showed to be most effective under conditions of free radical excess, while QUH was most effective when the flavonoid far exceeds the concentration of free radical. It was found, by means of experimental and computational methods, that 4'-OH, 3-OH and 3'-OH are the main reactive sites of both conformers.

  8. Effect of quercetin and its metabolite on caveolin-1 expression induced by oxidized LDL and lysophosphatidylcholine in endothelial cells.

    PubMed

    Kamada, Chiemi; Mukai, Rie; Kondo, Akari; Sato, Shinya; Terao, Junji

    2016-05-01

    Oxidized low-density lipoprotein contributes to atherosclerotic plaque formation, and quercetin is expected to exert anti-atherosclerotic effects. We previously reported accumulation of conjugated quercetin metabolites in the aorta of rabbits fed high-cholesterol diets with quercetin glucosides, resulting in attenuation of lipid peroxidation and inhibition of lipid accumulation. Caveolin-1, a major structural protein of caveolae in vascular endothelial cells, plays a role in atherosclerosis development. Here we investigated effects of oxidized low-density lipoprotein, quercetin and its metabolite, quercetin 3-O-β-glucuronide, on caveolin-1 expression. Oxidized low-density lipoprotein significantly upregulated caveolin-1 mRNA expression. An oxidized low-density lipoprotein component, lysophosphatidylcholine, also induced expression of both caveolin-1 mRNA and protein. However, lysophosphatidylcholine did not affect the location of caveolin-1 proteins within caveolae structures. Co-treatment with quercetin or quercetin 3-O-β-glucuronide inhibited lysophosphatidylcholine-induced caveolin-1 expression. Quercetin and quercetin 3-O-β-glucuronide also suppressed expression of adhesion molecules induced by oxidized low-density lipoprotein and lysophosphatidylcholine. These results strongly suggest lysophosphatidylcholine derived from oxidized low-density lipoprotein contributes to atherosclerotic events by upregulating caveolin-1 expression, resulting in induction of adhesion molecules. Quercetin metabolites are likely to exert an anti-atherosclerotic effect by attenuating caveolin-1 expression in endothelial cells. PMID:27257344

  9. Effect of quercetin and its metabolite on caveolin-1 expression induced by oxidized LDL and lysophosphatidylcholine in endothelial cells

    PubMed Central

    Kamada, Chiemi; Mukai, Rie; Kondo, Akari; Sato, Shinya; Terao, Junji

    2016-01-01

    Oxidized low-density lipoprotein contributes to atherosclerotic plaque formation, and quercetin is expected to exert anti-atherosclerotic effects. We previously reported accumulation of conjugated quercetin metabolites in the aorta of rabbits fed high-cholesterol diets with quercetin glucosides, resulting in attenuation of lipid peroxidation and inhibition of lipid accumulation. Caveolin-1, a major structural protein of caveolae in vascular endothelial cells, plays a role in atherosclerosis development. Here we investigated effects of oxidized low-density lipoprotein, quercetin and its metabolite, quercetin 3-O-β-glucuronide, on caveolin-1 expression. Oxidized low-density lipoprotein significantly upregulated caveolin-1 mRNA expression. An oxidized low-density lipoprotein component, lysophosphatidylcholine, also induced expression of both caveolin-1 mRNA and protein. However, lysophosphatidylcholine did not affect the location of caveolin-1 proteins within caveolae structures. Co-treatment with quercetin or quercetin 3-O-β-glucuronide inhibited lysophosphatidylcholine-induced caveolin-1 expression. Quercetin and quercetin 3-O-β-glucuronide also suppressed expression of adhesion molecules induced by oxidized low-density lipoprotein and lysophosphatidylcholine. These results strongly suggest lysophosphatidylcholine derived from oxidized low-density lipoprotein contributes to atherosclerotic events by upregulating caveolin-1 expression, resulting in induction of adhesion molecules. Quercetin metabolites are likely to exert an anti-atherosclerotic effect by attenuating caveolin-1 expression in endothelial cells. PMID:27257344

  10. Effects of dietary quercetin on performance and cytochrome P450 expression of the cotton bollworm, Helicoverpa armigera.

    PubMed

    Liu, D; Yuan, Y; Li, M; Qiu, X

    2015-12-01

    Quercetin is ubiquitous in terrestrial plants. The cotton bollworm Helicoverpa armigera as a highly polyphagous insect has caused severe crop losses. Until now, interactions between this pest and quercetin are poorly understood at the biochemical and molecular levels. In this study, we investigated the in vivo effects of quercetin on performance of cotton bollworm and on cytochrome P450 (P450) expression. Deleterious effects of quercetin on the performance of the cotton bollworm, including growth, survival, pupation and adult emergence were observed after oral administration of 3 and 10 mg g(-1) quercetin to larvae since the third instar, whereas no significant toxic effect was found at 0.1 mg g(-1) quercetin treatment. Piperonyl butoxide treatment enhanced the toxicity of quercetin. In vitro metabolism studies showed that quercetin was rapidly transformed by gut enzymes of fifth instar larvae of the cotton bollworm. qRT-PCR results revealed that the effect of quercetin on P450 expression was tissue- and dose-specific. Quercetin regulated P450 expression in a mild manner, and it could serve as P450 inducer (CYP337B1, CYP6B6) or repressor (CYP337B1, CYP6B7, CYP6B27, CYP9A14, CYP6AE11, and CYP4M7). These findings are important for advancing our understanding of the biochemical and molecular response of insects to plant toxins and have implications for a smart pest control. PMID:26440448

  11. Role of quercetin on mitomycin C induced genotoxicity: analysis of micronucleus and chromosome aberrations in vivo.

    PubMed

    Mazumdar, Mehnaz; Giri, Sarbani; Giri, Anirudha

    2011-04-01

    Quercetin, a flavonol group of plant flavonoid, has generated immense interest because of its potential antioxidant, anti-proliferative, chemoprotective, anti-inflammatory and gene expression modulating properties. However, the pro-oxidant chemistry of quercetin is important as it is related to the generation of mutagenic quinone-type metabolites. In the present study, 25mg/kg, 50mg/kg and 100mg/kg of quercetin given through the intra peritoneal (i.p.) route induced 2.31 ± 0.27%, 4.72 ± 0.58% and 6.38 ± 0.68% (control value=0.67 ± 0.30%) respectively, of cells with micronucleus (MN) in polychromatic erythrocytes in bone marrow cells and 10.93 ± 0.98%, 10.00 ± 0.89% and 14.27 ± 3.94% (control 2.61 ± 0.48) of cells with chromosome aberrations (CA) following 24h of the treatments. Higher frequencies of MN and CA were also observed after 48h of the treatments. To verify the effect of route of treatment on the quercetin induced damage, 100mg/kg b.w. was given through oral route which declined frequency of MN (P<0.001) as well as CA (P<0.05) as compared to the i.p. route for the same dose. Quercetin also induced higher frequency of metaphases with sticky chromosomes and C-mitosis. Pre-treatment with quercetin significantly reduced the frequency of mitomycin C (MMC) induced MN as well as CA, but no clear correlation between the dose and effect could be observed. Further studies are required to elucidate the possible interaction of quercetin with DNA as well as with other DNA damaging agents like MMC in vivo. The protective action of quercetin was not enhanced when given orally. Our findings suggest that quercetin may result in genomic instability in the tested dose range and significant reduction in MMC induced genotoxicity in the highest dose tested. These effects of quercetin are to be taken into consideration while evaluating the possible use of quercetin as a therapeutic agent. PMID:21256974

  12. Quercetin, a flavonoid antioxidant, modulates endothelium-derived nitric oxide bioavailability in diabetic rat aortas.

    PubMed

    Machha, Ajay; Achike, Francis I; Mustafa, Ali Mohd; Mustafa, Mohd Rais

    2007-06-01

    The present work examined the effect of chronic oral administration of quercetin, a flavonoid antioxidant, on blood glucose, vascular function and oxidative stress in STZ-induced diabetic rats. Male Wistar-Kyoto (WKY) rats were randomized into euglycemic, untreated diabetic, vehicle (1% w/v methylcellulose)-treated diabetic, which served as control, or quercetin (10mgkg(-1) body weight)-treated diabetic groups and treated orally for 6 weeks. Quercetin treatment reduced blood glucose level in diabetic rats. Impaired relaxations to endothelium-dependent vasodilator acetylcholine (ACh) and enhanced vasoconstriction responses to alpha(1)-adrenoceptor agonist phenylephrine (PE) in diabetic rat aortic rings were restored to euglycemic levels by quercetin treatment. Pretreatment with N(omega)-nitro-l-arginine methyl ester (l-NAME, 10microM) or methylene blue (10microM) completely blocked but indomethacin (10microM) did not affect relaxations to ACh in aortic rings from vehicle- or quercetin-treated diabetic rats. PE-induced vasoconstriction with an essentially similar magnitude in vehicle- or quercetin-treated diabetic rat aortic rings pretreated with l-NAME (10microM) plus indomethacin (10microM). Quercetin treatment reduced plasma malonaldehyde (MDA) plus 4-hydroxyalkenals (4-HNE) content as well as increased superoxide dismutase activity and total antioxidant capacity in diabetic rats. From the present study, it can be concluded that quercetin administration to diabetic rats restores vascular function, probably through enhancement in the bioavailability of endothelium-derived nitric oxide coupled to reduced blood glucose level and oxidative stress. PMID:17513143

  13. Quercetin Induces Hepatic Lipid Omega-Oxidation and Lowers Serum Lipid Levels in Mice

    PubMed Central

    Hoek-van den Hil, Elise F.; Keijer, Jaap; Bunschoten, Annelies; Vervoort, Jacques J. M.; Stankova, Barbora; Bekkenkamp, Melissa; Herreman, Laure; Venema, Dini; Hollman, Peter C. H.; Tvrzicka, Eva; Rietjens, Ivonne M. C. M.; van Schothorst, Evert M.

    2013-01-01

    Elevated circulating lipid levels are known risk factors for cardiovascular diseases (CVD). In order to examine the effects of quercetin on lipid metabolism, mice received a mild-high-fat diet without (control) or with supplementation of 0.33% (w/w) quercetin for 12 weeks. Gas chromatography and 1H nuclear magnetic resonance were used to quantitatively measure serum lipid profiles. Whole genome microarray analysis of liver tissue was used to identify possible mechanisms underlying altered circulating lipid levels. Body weight, energy intake and hepatic lipid accumulation did not differ significantly between the quercetin and the control group. In serum of quercetin-fed mice, triglycerides (TG) were decreased with 14% (p<0.001) and total poly unsaturated fatty acids (PUFA) were increased with 13% (p<0.01). Palmitic acid, oleic acid, and linoleic acid were all decreased by 9–15% (p<0.05) in quercetin-fed mice. Both palmitic acid and oleic acid can be oxidized by omega (ω)-oxidation. Gene expression profiling showed that quercetin increased hepatic lipid metabolism, especially ω-oxidation. At the gene level, this was reflected by the up-regulation of cytochrome P450 (Cyp) 4a10, Cyp4a14, Cyp4a31 and Acyl-CoA thioesterase 3 (Acot3). Two relevant regulators, cytochrome P450 oxidoreductase (Por, rate limiting for cytochrome P450s) and the transcription factor constitutive androstane receptor (Car; official symbol Nr1i3) were also up-regulated in the quercetin-fed mice. We conclude that quercetin intake increased hepatic lipid ω-oxidation and lowered corresponding circulating lipid levels, which may contribute to potential beneficial effects on CVD. PMID:23359794

  14. A novel solid fluorescence method for the fast determination of quercetin in biological samples based on the quercetin-Al(III) complex imprinted polymer

    NASA Astrophysics Data System (ADS)

    Hu, Yufei; Feng, Ting; Li, Gongke

    2014-01-01

    In this work, a novel solid fluorescence method was proposed and applied to the fast determination of quercetin in urine and onion skin samples by using metal coordination imprinted polymer membrane, which was regarded as a recognition element. The quercetin-Al(III) imprinted polymer was immobilized in the microporous polypropylene fiber membrane via consecutive in situ polymerization. The CIP membrane had the porous, loose and layer upon layer structure. The CIP membrane was characterized by electron microscope photographs, infrared spectra, thermogravimetric analysis and solvent-resistant investigation. The extraction conditions including extraction solvent, extraction time, desorption solvent were optimized. Compared with MIP and NIP membrane, CIP membrane had been proved to be peculiar selective for quercetin even in presence of the structurally similar compounds such as kaempferol, rutin, naringenin and alpinetin. The CIP membrane was characteristic of high selectivity, stable and sensitive response to quercetin in polar environment. Under the optimum condition, there was a linear relationship between the state fluorescent response and the concentration of quercetin. The linear calibration range was over 0.02 mg L-1-0.80 mg L-1 with a detection limit of 5 μg L-1. The method was characteristic of flexible and good repeatability with relative standard deviation (RSD) of 4.1%. The proposed method was also successfully applied for the determination of quercetin in urine and onion skin samples without complicated pretreatment. The recoveries were 84.0-112.4% and RSDs varied from 1.5% to 6.8%. The results obtained by the proposed method agreed well with those obtained by HPLC method.

  15. Quercetin alleviates myocyte toxic and sensitizes anti-leukemic effect of adriamycin.

    PubMed

    Han, Yanqiu; Yu, Hong; Wang, Junrui; Ren, Yanzhen; Su, Xiulan; Shi, Yingxu

    2015-06-01

    Objectives Derived from plants, flavonoids have been proven to possess anti-cancer activities. Adriamycin (ADM), an anthracycline antibiotic, is widely applied in the chemotherapy for leukemia; however, it has a side effect of heart damage. This study aims to explore potential anti-leukemia effects of quercetin (Que) and the underlying mechanism. Methods The P388 xenograft mice models were first established and then treated with Que alone or in combination with ADM. Subsequently, we evaluated their effects on cell proliferation and apoptosis by observing the cell cycle and detecting the Caspase-3 level, respectively. The underlying pro-apoptotic mechanism was further investigated by detecting the expression levels of NF-κB, Bcl-2, and Bax. The cardiomyocyte ultrastructural changes of P388 leukemic mice after drug treatment were also observed. The protective effect of Que on cardiomyocyte was evaluated by detecting enzymatic activity changes of glutathione peroxidase, superoxide dismutase, and malondialdehyde. Results Compared with ADM group, the combination of ADM and Que showed prolonged survival time and less peripheral white blood cells. Que could sensitize the anti-leukemic effect of ADM by inhibiting the proliferation of white blood cells through trapping the cells at the S phase; caspase-3 was activated via the expressional regulation of Bcl-2, Bax, and NF-κB. When applied in combination with ADM, Que could attenuate heart damage by cleaning the reactive oxygen species. Conclusion Our study may provide informative evidences for the underlying mechanism of anti-cancer effects of Que and sheds light on the clinical application of Que in leukemia treatment. PMID:25201038

  16. Potential of Excipient Emulsions for Improving Quercetin Bioaccessibility and Antioxidant Activity: An in Vitro Study.

    PubMed

    Chen, Xing; Zou, Liqiang; Liu, Wei; McClements, David Julian

    2016-05-11

    The potential for excipient emulsions to enhance the bioaccessibility and antioxidant activity of quercetin was determined in this study. Oil-in-water excipient emulsions containing two levels (4 or 10%) of small lipid droplets (d < 250 nm) were prepared from a long-chain triglyceride (corn oil). The solubilization of quercetin by the excipient emulsions was faster than by bulk corn oil or bulk water, and the solubilization rate was higher at 100 °C than at 30 °C. The bioaccessibility of quercetin samples was determined using an in vitro gastrointestinal model, and the bioactivity of quercetin was determined using a rat feeding study. The excipient emulsions were more effective at enhancing quercetin bioaccessibility and rat plasma antioxidant activity than either bulk oil or bulk water. This effect was attributed to the rapid digestion of the long chain triglycerides when they were in an emulsified form, which led to the rapid production of mixed micelles capable of solubilizing, protecting, and transporting quercetin. PMID:27136205

  17. Protective effect of rosiglitazone, quercetin, and their combination on fructose-induced metabolic syndrome in rats

    PubMed Central

    Abo-youssef, Amira M.

    2015-01-01

    Objectives: Quercetin exhibits a wide range of biological functions. The present study aimed to investigate the possible beneficial effects of rosiglitazone, quercetin as well as their combination on metabolic and biochemical changes associated with the fructose-induced metabolic syndrome (MS). Materials and Methods: Four groups of rats were fed on fructose-enriched diet for 14 weeks. One group served as fructose-enriched diet control, while the remaining groups were treated with rosiglitazone (4 mg/kg/day), quercetin (50 mg/kg/day), and their combination during the last 4 weeks. A fifth group was fed on normal laboratory diet. At the end of the experiment, blood samples were withdrawn for the estimation of markers of MS. Results: Rosiglitazone or quercetin attenuated the biochemical and metabolic changes associated with MS. The combination of rosiglitazone and quercetin nearly normalized these changes. Conclusion: Quercetin, as well as its combination with rosiglitazone, showed beneficial protective effects against metabolic and biochemical changes associated with MS. PMID:26729953

  18. Quercetin inhibits advanced glycation end product formation by trapping methylglyoxal and glyoxal.

    PubMed

    Li, Xiaoming; Zheng, Tiesong; Sang, Shengmin; Lv, Lishuang

    2014-12-17

    Methylglyoxal (MGO) and glyoxal (GO) not only are endogenous metabolites but also exist in exogenous resources, such as foods, beverages, urban atmosphere, and cigarette smoke. They have been identified as reactive dicarbonyl precursors of advanced glycation end products (AGEs), which have been associated with diabetes-related long-term complications. In this study, quercetin, a natural flavonol found in fruits, vegetables, leaves, and grains, could effectively inhibit the formation of AGEs in a dose-dependent manner via trapping reactive dicarbonyl compounds. More than 50.5% of GO and 80.1% of MGO were trapped at the same time by quercetin within 1 h under physiological conditions. Quercetin and MGO (or GO) were combined at different ratios, and the products generated from this reaction were analyzed with LC-MS. Both mono-MGO and di-MGO adducts of quercetin were detected in this assay using LC-MS, but only tiny amounts of mono-GO adducts of quercetin were found. Additionally, di-MGO adducts were observed as the dominant product with prolonged incubation time. In the bovine serum albumin (BSA)-MGO/GO system, quercetin traps MGO and GO directly and then significantly inhibits the formation of AGEs. PMID:25412188

  19. Quercetin alleviates inflammation after short-term treatment in high-fat-fed mice.

    PubMed

    Das, Nilanjan; Sikder, Kunal; Bhattacharjee, Surajit; Majumdar, Suchandra Bhattacharya; Ghosh, Santinath; Majumdar, Subrata; Dey, Sanjit

    2013-06-01

    Consumption of a high-fat diet (HFD) promotes reactive oxygen species (ROS) which ultimately trigger inflammation. The aim of this study was to investigate the role of Moringa oleifera leaf extract (MoLE) and its active component quercetin in preventing NF-κB-mediated inflammation raised by short-term HFD. Quercetin was found to be one of the major flavonoid components from HPLC of MoLE. Swiss mice were fed for 15 days on HFD, both with or without MoLE/quercetin. The antioxidant profile was estimated from liver homogenate. NF-κB and some relevant inflammatory markers were evaluated by immunoblotting, RT-PCR and ELISA. Significantly (P < 0.05) lower antioxidant profile and higher lipid peroxidation was found in HFD group compared to control (P < 0.05). Increased nuclear import of NF-κB and elevated expressions of pro-inflammatory markers were further manifestations in the HFD group. All these changes were reversed in the MoLE/quercetin-treated groups with significant improvement of antioxidant activity compared to the HFD group. MoLE was found to be rich in polyphenols and both MoLE and quercetin showed potent free radical and hydroxyl radical quenching activity. Thus, the present study concluded that short-term treatment with MoLE and its constituent quercetin prevent HFD-mediated inflammation in mice. PMID:23644882

  20. Quercetin negatively regulates TLR4 signaling induced by lipopolysaccharide through Tollip expression.

    PubMed

    Byun, Eui-Baek; Yang, Mi-So; Choi, Han-Gyu; Sung, Nak-Yun; Song, Du-Sup; Sin, Sung-Jae; Byun, Eui-Hong

    2013-02-22

    Polyphenolic compounds have been regarded as one of the most promising dietary agents for the prevention and treatment of inflammation-related chronic diseases; however, the anti-inflammatory activities of flavonoids, such as quercetin, are not completely characterized, and many features remain to be elucidated. In this study, we showed the molecular basis for the downregulation of TLR4 signal transduction by quercetin. Quercetin markedly elevated the expression of the Toll-interacting protein, a negative regulator of TLR signaling. Lipopolysaccharide-induced expression of cell surface molecules (CD80, CD86, and MHC class I/II) and production of pro-inflammatory cytokines (tumor necrosis factor-α, IL-1β, IL-6, and IL-12p70) were inhibited by quercetin, and this action was prevented by Toll-interacting protein silencing. In addition, quercetin-treated macrophages inhibited lipopolysaccharide-induced activation of mitogen-activated protein kinases, such as extracellular signal-regulated kinase 1/2, p38, and c-Jun N-terminal kinase, and the translocation of nuclear factor-κB and p65 through Toll-interacting protein. Treatment with quercetin resulted in a significant decrease in prostaglandin E2 and cyclooxygenase-2 levels as well as inducible nitric oxide synthase-mediated nitric oxide production induced by lipopolysaccharide. Taken together, these findings represent new insights into the understanding of negative regulatory mechanisms of the TLR4 signaling pathway and effective therapeutic intervention for the treatment of inflammatory disease. PMID:23353651

  1. Quercetin protects against high glucose-induced damage in bone marrow-derived endothelial progenitor cells.

    PubMed

    Zhao, Li-Rong; Du, Yu-Jun; Chen, Lei; Liu, Zhi-Gang; Pan, Yue-Hai; Liu, Jian-Feng; Liu, Bin

    2014-10-01

    Endothelial progenitor cells (EPCs), a group of bone marrow-derived pro-angiogenic cells, contribute to vascular repair after damage. EPC dysfunction exists in diabetes and results in poor wound healing in diabetic patients with trauma or surgery. The aim of the present study was to determine the effect of quercetin, a natural flavonoid on high glucose‑induced damage in EPCs. Treatment with high glucose (40 mM) decreased cell viability and migration, and increased oxidant stress, as was evidenced by the elevated levels of reactive oxygen species (ROS), malondialdehyde (MDA) and superoxide dismutase in bone marrow-derived EPCs. Moreover, high glucose reduced the levels of endothelial nitric oxide synthase (eNOS) phosphorylation, nitric oxide (NO) production and intracellular cyclic guanosine monophosphate (cGMP). Quercetin supplement protected against high glucose‑induced impairment in cell viability, migration, oxidant stress, eNOS phosphorylation, NO production and cGMP levels. Quercetin also increased Sirt1 expression in EPCs. Inhibition of Sirt1 by a chemical antagonist sirtinol abolished the protective effect of quercetin on eNOS phosphorylation, NO production and cGMP levels following high glucose stress. To the best of our knowledge, the results provide the first evidence that quercetin protects against high glucose‑induced damage by inducing Sirt1-dependent eNOS upregulation in EPCs, and suggest that quercetin is a promising therapeutic agent for diabetic patients undergoing surgery or other invasive procedures. PMID:25197782

  2. Development of an antioxidant biomaterial by promoting the deglycosylation of rutin to isoquercetin and quercetin.

    PubMed

    Cruz-Zúñiga, Johana M; Soto-Valdez, Herlinda; Peralta, Elizabeth; Mendoza-Wilson, Ana María; Robles-Burgueño, M Refugio; Auras, Rafael; Gámez-Meza, Nohemí

    2016-08-01

    Quercetin-3-O-rutinoside (rutin), quercetin-3-O-glucoside (isoquercetin) and quercetin have shown antioxidant, cytoprotective, vasoprotective, antiproliferative and antiinflammatory properties. The aim of this work was to determine the conversion of rutin to isoquercetin and quercetin during the production of poly(l-lactic acid) films with potential to deliver these flavonoids toward tissues, pharmaceuticals or food matrices. Three poly(l-lactic acid) formulations with 17.7, 39.6 and 39.1mg/g of rutin were prepared by the extrusion process. Processing temperatures (130-165°C) promoted the deglycosylation of rutin to produce isoquercetin and subsequently quercetin, identified by high performance liquid chromatography coupled to mass spectrometry. The effect of the process on the antioxidant activity of the films was determined by measuring the capacity to scavenge 2,2 diphenyl-1-picrylhydrazyl radicals. The material with the highest proportion of quercetin showed the highest antioxidant activity which could be used to produce delivering devices of the flavonoids to tissues, pharmaceuticals or food matrices. PMID:26988520

  3. Protective Effects of Quercetin against Dimethoate-Induced Cytotoxicity and Genotoxicity in Allium sativum Test

    PubMed Central

    Ahmad, Waseem; Shaikh, Sibhghatulla; Nazam, Nazia; Lone, Mohammad Iqbal

    2014-01-01

    The present investigation was directed to study the possible protective activity of quercetin—a natural antioxidant against dimethoate-induced cyto- and genotoxicity in meristematic cells of Allium sativum. So far there is no report on the biological properties of quercetin in plant test systems. Chromosome breaks, multipolar anaphase, stick chromosome, and mitotic activity were undertaken in the current study as markers of cyto- and genotoxicity. Untreated control, quercetin controls (@ 5, 10 and 20 μg/mL for 3 h), and dimethoate exposed groups (@ 100 and 200 μg/mL for 3 h) were maintained. For protection against cytogenotoxicity, the root tip cells treated with dimethoate at 100 and 200 μg/mL for 3 h and quercetin treatment at 5, 10, and 20 μg/mL for 16 h, prior to dimethoate treatment, were undertaken. Quercetin was found to be neither cytotoxic nor genotoxic in Allium sativum control at these doses. A significant increase (P < 0.05) in chromosomal aberrations was noted in dimethoate treated Allium. Pretreatment of Allium sativum with quercetin significantly (P < 0.05) reduced dimethoate-induced genotoxicity and cytotoxicity in meristematic cells, and these effects were dose dependent. In conclusion, quercetin has a protective role in the abatement of dimethoate-induced cyto- and genotoxicity in the meristematic cells of Allium sativum that resides, at least in part, on its antioxidant effects. PMID:27379342

  4. Quercetin protects human peripheral blood mononuclear cells from OTA-induced oxidative stress, genotoxicity, and inflammation.

    PubMed

    Periasamy, Ramyaa; Kalal, Iravathy Goud; Krishnaswamy, Rajashree; Viswanadha, VijayaPadma

    2016-07-01

    Ochratoxin A (OTA) is one of the most abundant food-contaminating mycotoxins world wide, and is detrimental to human and animal health. This study evaluated the protective effect of quercetin against OTA-induced cytotoxicity, genotoxicity, and inflammatory response in lymphocytes. Cytotoxicity determined by MTT assay revealed IC20 value of OTA to be 20 µM, which was restored to near control values by pretreatment with quercetin. Oxidative stress parameters such as antioxidant enzymes, LPO and PCC levels indicated that quercetin exerted a protective effect on OTA-induced oxidative stress. Quercetin exerted an antigenotoxic effect on OTA-induced genotoxicity, by significantly reducing the number of structural aberrations in chromosomes and comet parameters like, % olive tail moment from 2.76 ± 0.02 to 0.56 ± 0.02 and % tail DNA from 56.23 ± 2.56 to 12.36 ± 0.56 as determined by comet assay. OTA-induced NO, TNF-α, IL-6, and IL-8 were significantly reduced in the quercetin pretreated samples indicating its anti-inflammatory role. Our results demonstrate for the first time that quercetin exerts a cytoprotective effect against OTA-induced oxidative stress, genotoxicity, and inflammation in lymphocytes. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 855-865, 2016. PMID:25532488

  5. Quercetin/beta-cyclodextrin solid complexes prepared in aqueous solution followed by spray-drying or by physical mixture.

    PubMed

    Borghetti, Greice S; Lula, Ivana S; Sinisterra, Ruben D; Bassani, Valquiria L

    2009-01-01

    The present study was designed to investigate the influence of operating conditions (temperature, stirring time, and excess amount of quercetin) on the complexation of quercetin with beta-cyclodextrin using a 2(3) factorial design. The highest aqueous solubility of quercetin was reached under the conditions 37 degrees C/24 h/6 mM of quercetin. The stoichiometric ratio (1:1) and the apparent stability constant (Ks = 230 M(-1)) of the quercetin/beta-cyclodextrin complex were determined using phase-solubility diagrams. The semi-industrial production of a 1:1 quercetin/beta-cyclodextrin solid complex was carried out in aqueous solution followed by spray-drying. Although the yield of the spray-drying process was adequate (77%), the solid complex presented low concentration of quercetin (0.14%, w/w) and, thus, low complexation efficiency. The enhancement of aqueous solubility of quercetin using this method was limited to 4.6-fold in the presence of 15 mM of beta-cyclodextrin. Subsequently, an inclusion complex was prepared via physical mixture of quercetin with beta-cyclodextrin (molar ratio of 1:1 and quercetin concentration of 23% (w/w)) and characterized using infrared spectroscopy, differential scanning calorimetry, nuclear magnetic resonance spectroscopy, and scanning electron microscopy analyses. The enhancement of aqueous solubility of quercetin using this method was 2.2-fold, similar to that found in the complex prepared in aqueous solution before the spray-drying process (2.5-fold at a molar ratio of 1:1, i.e., 6 mM of quercetin and 6 mM of beta-cyclodextrin). PMID:19280349

  6. Amperometric monitoring of quercetin permeation through skin membranes.

    PubMed

    Rembiesa, Jadwiga; Gari, Hala; Engblom, Johan; Ruzgas, Tautgirdas

    2015-12-30

    Transdermal delivery of quercetin (QR, 3,3',4',5,7-pentahydroxyflavone), a natural flavonoid with a considerable antioxidant capacity, is important for medical treatment of, e.g., skin disorders. QR permeability through skin is low, which, at the same time, makes the monitoring of percutaneous QR penetration difficult. The objective of this study was to assess an electrochemical method for monitoring QR penetration through skin membranes. An electrode was covered with the membrane, exposed to QR solution, and electrode current was measured. The registered current was due to electro-oxidation of QR penetrating the membrane. Exploiting strict current-QR flux relationships diffusion coefficient, D, of QR in skin and dialysis membranes was calculated. The D values were strongly dependent on the theoretical model and parameters assumed in the processing of the amperometric data. The highest values of D were in the range of 1.6-6.1×10(-7)cm(2)/s. This was reached only for skin membranes pretreated with buffer-ethanol mixture for more than 24h. QR solutions containing penetration enhancers, ethanol and l-menthol, definitely increased D values. The results demonstrate that electrochemical setup gives a possibility to assess penetration characteristics as well as enables monitoring of penetration dynamics, which is more difficult by traditional methods using Franz cells. PMID:26541297

  7. Kinetic spectrophotometric determination of certain cephalosporins using oxidized quercetin reagent

    NASA Astrophysics Data System (ADS)

    Saleh, Gamal A.; El-Shaboury, Salwa R.; Mohamed, Fardous A.; Rageh, Azza H.

    2009-09-01

    A simple, precise and accurate kinetic spectrophotometric method for determination of cefoperazone sodium, cefazolin sodium and ceftriaxone sodium in bulk and in pharmaceutical formulations has been developed. The method is based upon a kinetic investigation of the reaction of the drug with oxidized quercetin reagent at room temperature for a fixed time of 30 min. The decrease in absorbance after the addition of the drug was measured at 510 nm. The absorbance concentration plot was rectilinear over the range 80-400 μg mL -1 for all studied drugs. The concentration of the studied drugs was calculated using the corresponding calibration equation for the fixed time method. The determination of the studied drugs by initial rate, variable time and rate-constant methods was feasible with the calibration equations obtained but the fixed time method has been found to be more applicable. The analytical performance of the method, in terms of accuracy and precision, was statistically validated; the results were satisfactory. The method has been successfully applied to the determination of the studied drugs in commercial pharmaceutical formulations. Statistical comparison of the results with a well established reported method showed excellent agreement and proved that there is no significant difference in the accuracy and precision.

  8. Design and characterization of protein-quercetin bioactive nanoparticles

    PubMed Central

    2011-01-01

    Background The synthesis of bioactive nanoparticles with precise molecular level control is a major challenge in bionanotechnology. Understanding the nature of the interactions between the active components and transport biomaterials is thus essential for the rational formulation of bio-nanocarriers. The current study presents a single molecule of bovine serum albumin (BSA), lysozyme (Lys), or myoglobin (Mb) used to load hydrophobic drugs such as quercetin (Q) and other flavonoids. Results Induced by dimethyl sulfoxide (DMSO), BSA, Lys, and Mb formed spherical nanocarriers with sizes less than 70 nm. After loading Q, the size was further reduced by 30%. The adsorption of Q on protein is mainly hydrophobic, and is related to the synergy of Trp residues with the molecular environment of the proteins. Seven Q molecules could be entrapped by one Lys molecule, 9 by one Mb, and 11 by one BSA. The controlled releasing measurements indicate that these bioactive nanoparticles have long-term antioxidant protection effects on the activity of Q in both acidic and neutral conditions. The antioxidant activity evaluation indicates that the activity of Q is not hindered by the formation of protein nanoparticles. Other flavonoids, such as kaempferol and rutin, were also investigated. Conclusions BSA exhibits the most remarkable abilities of loading, controlled release, and antioxidant protection of active drugs, indicating that such type of bionanoparticles is very promising in the field of bionanotechnology. PMID:21586116

  9. Quercetin mitigates fenitrothion-induced testicular toxicity in rats.

    PubMed

    Saber, T M; Abd El-Aziz, R M; Ali, H A

    2016-06-01

    Fenitrothion (FNT) is a widely used organophosphorus pesticide in agriculture. Quercetin (QR), a plant-derived flavonoid, has a free radical scavenging property. This study investigated the protective effect of QR on FNT-induced testicular toxicity in rats. Twenty-four male rats were divided into four groups. Group I (control) received normal saline. Group II was administered QR at the dose of 50 mg kg(-1) b.wt. Group III was orally administered FNT (20 mg kg(-1) b.wt). Group IV was gavaged FNT and QR together at the same doses. All administrations were performed daily by gavage and maintained for 70 days. Sperm parameters and histopathological changes in testes were investigated. Serum testosterone and luteinising hormone were estimated using radioimmunoassay kits. In testes, expressions of steroidogenic genes (3β-hydroxysteroid dehydrogenase type 6, 17 β-hydroxysteroid dehydrogenase type 3 and steroidogenic factor-1) and oxidative stress genes (catalase and superoxide dismutase) were determined using real-time PCR. FNT administration caused significant decreases in sperm count, motility and hormonal levels, a significant increase in abnormal sperm morphology and a significant down-regulation of steroidogenic and antioxidant genes in the testis. However, QR administration ameliorated FNT-induced toxic effects. Our results concluded that QR effectively mitigated testicular damage induced by FNT in rats. PMID:26264430

  10. Enhanced electrochemical detection of quercetin by Natural Deep Eutectic Solvents.

    PubMed

    Gomez, Federico José Vicente; Espino, Magdalena; de Los Angeles Fernandez, María; Raba, Julio; Silva, María Fernanda

    2016-09-14

    New trends in analytical chemistry encourage the development of smart techniques and methods aligned with Green Chemistry. In this sense, Natural Deep Eutectic Solvents represents an excellent opportunity as a new generation of green solvents. In this work a new application for them has been proposed and demonstrated. These solvents were synthesized by combinations of inexpensive and natural components like, Glucose, Fructose, Citric acid and Lactic acid. The different natural solvents were easily prepared and added to buffer solution in different concentrations, allowing the enhancement of electrochemical detection of an important representative antioxidant like quercetin (QR) with improved signal up to 380%. QR is a ubiquitous flavonoid widespread in plants and food of plant origin. The proposed method using phosphate buffer with a eutectic mixture of Citric acid, Glucose and water in combination with carbon screen printed electrodes exhibited a good analytical performance. Detection and quantification limits were of 7.97 and 26.3 nM respectively; and repeatability with %RSDs of 1.41 and 7.49 for peak potential and intensity respectively. In addition, it has proved to be faster, greener and cheaper than other sensors and chromatographic methods available with the additional advantage of being completely portable. Furthermore, the obtained results demonstrated that the proposed method is able for the determination of QR in complex food samples. PMID:27566343

  11. Quercetin Influence on Thermal Denaturation of Bovine Serum Albumin.

    PubMed

    Precupas, Aurica; Sandu, Romica; Popa, Vlad T

    2016-09-01

    The effect of quercetin (QUER) binding on bovine serum albumin (BSA) thermal denaturation was systematically investigated by means of differential scanning calorimetry (DSC). Additional information concerning thermodynamic and structural binding parameters was provided by isothermal titration calorimetry (ITC) and molecular docking. The most relevant effect of QUER is manifested in the modification of the two-step thermal fingerprint of protein denaturation. Higher QUER concentrations result in a single-step denaturation thermogram, ascribed to the interplay between specific and nonspecific binding and enhancement of the solvent unfolding action. Analysis of ITC data indicate sequential binding of two molecules of QUER occurring spontaneously at different binding sites of BSA involving hydrophobic, electrostatic and hydrogen binding forces. Identification of QUER binding sites was possible through corroboration of DSC runs in the presence of site markers and molecular docking. Modeling of ligand-protein interaction confirmed the experimental data. On one hand, a neutral form of QUER binds in a nonplanar conformation to Sudlow's site I, a large hydrophobic cavity of subdomain IIA of BSA and decreases its thermal stability. On the other hand, a second molecule of QUER, the anionic form, is bound in planar conformation to Sudlow's site II, situated in the subdomain IIIA of the folded protein, and increases the thermal stability of the corresponding structural domain of the protein. PMID:27505141

  12. Cancer

    MedlinePlus

    ... body. Cancerous cells are also called malignant cells. Causes Cancer grows out of cells in the body. Normal ... of many cancers remains unknown. The most common cause of cancer-related death is lung cancer. In the U.S., ...

  13. Quercetin reduces obesity-associated ATM infiltration and inflammation in mice: a mechanism including AMPKα1/SIRT1.

    PubMed

    Dong, Jing; Zhang, Xian; Zhang, Lei; Bian, Hui-Xi; Xu, Na; Bao, Bin; Liu, Jian

    2014-03-01

    Adipose tissue macrophage (ATM) plays a central role in obesity-associated inflammation and insulin resistance. Quercetin, a dietary flavonoid, possesses anti-inflammation and anti-insulin resistance properties. However, it is unclear whether quercetin can alleviate high-fat diet (HFD)-induced ATM infiltration and inflammation in mice. In this study, 5-week-old C57BL/6 mice were fed low-fat diet, HFD, or HFD with 0.l% quercetin for 12 weeks, respectively. Dietary quercetin reduced HFD-induced body weight gain and improved insulin sensitivity and glucose intolerance in mice. Meanwhile, dietary quercetin enhanced glucose transporter 4 translocation and protein kinase B signal in epididymis adipose tissues (EATs), suggesting that it heightened glucose uptake in adipose tissues. Histological and real-time PCR analysis revealed that quercetin attenuated mast cell and macrophage infiltration into EATs in HFD-fed mice. Dietary quercetin also modified the phenotype ratio of M1/M2 macrophages, lowered the levels of proinflammatory cytokines, and enhanced adenosine monophosphate-activated protein kinase (AMPK) α1 phosphorylation and silent information regulator 1 (SIRT1) expression in EATs. Further, using AMPK activator 5-aminoimidazole-4-carboxamide-1-β4-ribofuranoside and inhibitor Compound C, we found that quercetin inhibited polarization and inflammation of mouse bone marrow-derived macrophages through an AMPKα1/SIRT1-mediated mechanism. In conclusion, dietary quercetin might suppress ATM infiltration and inflammation through the AMPKα1/SIRT1 pathway in HFD-fed mice. PMID:24465016

  14. Quercetin increases macrophage cholesterol efflux to inhibit foam cell formation through activating PPARγ-ABCA1 pathway

    PubMed Central

    Sun, Liqiang; Li, En; Wang, Feng; Wang, Tao; Qin, Zhiping; Niu, Shaohui; Qiu, Chunguang

    2015-01-01

    The accumulation of cholesterol in macrophages could induce the formation of foam cells and increase the risk of developing atherosclerosis. We wonder if quercetin, one of flavonoids with anti-inflammation functions in different cell types, could elevate the development of foam cells formation in atherosclerosis. We treated foam cells derived from oxLDL induced THP-1 cells with quercetin, and evaluated the foam cells formation, cholesterol content and apoptosis of the cells. We found that quercetin induced the expression of ABCA1 in differentiated THP-1 cells, and increased the cholesterol efflux from THP-1 cell derived foam cells. Eventually, cholesterol level and the formation of foam cell derived from THP-1 cells decreased after quercetin treatment. In addition, quercetin activated PPARγ-LXRα pathway to upregulate ABCA1 expression through increasing protein level of PPARγ and its transcriptional activity. Inhibition of PPARγ activity by siRNA knockdown or the addition of chemical inhibitor, GW9662, abolished quercetin induced ABCA1 expression and cholesterol efflux in THP-1 derived macrophages. Our data demonstrated that quercetin increased cholesterol efflux from macrophages through upregulating the expressions of PPARγ and ABCA1. Taken together, increasing uptake of quercetin or quercetin-rich foods would be an effective way to lower the risk of atherosclerosis. PMID:26617799

  15. Microsomal Quercetin Glucuronidation in Rat Small Intestine Depends on Age and Segment

    PubMed Central

    Bolling, Bradley W.; Court, Michael H.; Blumberg, Jeffrey B.

    2011-01-01

    UDP-glucuronosyltransferase (UGT) activity toward the flavonoid quercetin and UGT protein were characterized in three equidistant small intestine (SI) segments from 4-, 12-, 18-, and 28-month-old male Fischer 344 rats (n = 8/age) using villin to control for enterocyte content. SI microsomal intrinsic clearance of quercetin was increased 3- to 9-fold from 4 months in the proximal and distal SI at 12 and 18 months. Likewise, at 30 μM quercetin, SI microsomal glucuronidation activity was increased with age: 4.8- and 3.9-fold greater at 18 months than at 4 months. Quercetin UGT regioselectivity was not changed by age. The distal SI preferentially catalyzed glucuronidation at the 7-position, whereas the proximal SI produced the greatest proportion of 4′- and 3′-conjugates. Enterocyte UGT content in different SI segments was not consistently changed with age. In the proximal SI, UGT1A increased 64 and 150% at 12 and 18 months and UGT1A1, UGT1A7, and UGT1A8 were also increased at 12 and 18 months. However, age-related changes in expression were inconsistent in the medial and distal segments. Microsomal rates of quercetin glucuronidation and UGT expression were positively correlated with UGT1A1 content for all pooled samples (r = 0.467) and at each age (r = 0.538–0.598). UGT1A7 was positively correlated with total, 7-O- and 3-O-quercetin glucuronidation at 18 months. Thus, age-related differences in UGT quercetin glucuronidation depend on intestinal segment, are more pronounced in the proximal and distal segments and may be partially related to UGT1A1 and UGT1A7 content. PMID:21543555

  16. Quercetin alleviates pulmonary angiogenesis in a rat model of hepatopulmonary syndrome

    PubMed Central

    Li, X.; Chen, Y.; Wang, L.; Shang, G.; Zhang, C.; Zhao, Z.; Zhang, H.; Liu, A.

    2016-01-01

    Quercetin shows protective effects against hepatopulmonary syndrome (HPS), as demonstrated in a rat model. However, whether these effects involve pulmonary vascular angiogenesis in HPS remains unclear. Therefore, this study aimed to assess the effect of quercetin on pulmonary vascular angiogenesis and explore the underlying mechanisms. Male Sprague-Dawley rats weighing 200-250 g underwent sham operation or common bile duct ligation (CBDL). Two weeks after surgery, HIF-1α and NFκB levels were assessed in rat lung tissue by immunohistochemistry and western blot. Then, CBDL and sham-operated rats were further divided into 2 subgroups each to receive intraperitoneal administration of quercetin (50 mg/kg daily) or 0.2% Tween for two weeks: Sham (Sham+Tween; n=8), CBDL (CBDL+Tween; n=8), Q (Sham+quercetin; n=8), and CBDL+Q (CBDL+quercetin; n=8). After treatment, lung tissue specimens were assessed for protein (immunohistochemistry and western blot) and/or gene expression (quantitative real-time PCR) levels of relevant disease markers, including VEGFA, VEGFR2, Akt/p-Akt, HIF-1α, vWf, and IκB/p-IκB. Finally, arterial blood was analyzed for alveolar arterial oxygen pressure gradient (AaPO2). Two weeks after CBDL, HIF-1α expression in the lung decreased, but was gradually restored at four weeks. Treatment with quercetin did not significantly alter HIF-1α levels, but did reduce AaPO2 as well as lung tissue NF-κB activity, VEGFA gene and protein levels, Akt activity, and angiogenesis. Although hypoxia is an important feature in HPS, our findings suggest that HIF-1α was not the main cause for the VEGFA increase. Interestingly, quercetin inhibited pulmonary vascular angiogenesis in rats with HPS, with involvement of Akt/NF-κB and VEGFA/VEGFR-2 pathways. PMID:27383124

  17. Diabetic neuropathy: An evaluation of the use of quercetin in the cecum of rats

    PubMed Central

    Ferreira, Paulo Emilio Botura; Lopes, Cláudia Regina Pinheiro; Alves, Angela Maria Pereira; Alves, Éder Paulo Belato; Linden, David Robert; Zanoni, Jacqueline Nelisis; Buttow, Nilza Cristina

    2013-01-01

    AIM: To investigate the effect of quercetin supplementation on the myenteric neurons and glia in the cecum of diabetic rats. METHODS: Total preparations of the muscular tunic were prepared from the ceca of twenty-four rats divided into the following groups: control (C), control supplemented with quercetin (200 mg/kg quercetin body weight) (CQ), diabetic (D) and diabetic supplemented with quercetin (DQ). Immunohistochemical double staining technique was performed with HuC/D (general population)/nitric oxide synthase (nNOS), HuC-D/S-100 and VIP. Density analysis of the general neuronal population HuC/D-IR, the nNOS-IR (nitrergic subpopulation) and the enteric glial cells (S-100) was performed, and the morphometry and the reduction in varicosity population (VIP-IR) in these populations were analyzed. RESULTS: Diabetes promoted a significant reduction (25%) in the neuronal density of the HuC/D-IR (general population) and the nNOS-IR (nitrergic subpopulation) compared with the C group. Diabetes also significantly increased the areas of neurons, glial cells and VIP-IR varicosities. Supplementation with quercetin in the DQ group prevented neuronal loss in the general population and increased its area (P < 0.001) and the area of nitrergic subpopulation (P < 0.001), when compared to C group. Quercetin induced a VIP-IR and glial cells areas (P < 0.001) in DQ group when compared to C, CQ and D groups. CONCLUSION: In diabetes, quercetin exhibited a neuroprotective effect by maintaining the density of the general neuronal population but did not affect the density of the nNOS subpopulation. PMID:24151360

  18. Protective effect of quercetin on skeletal and neural tube teratogenicity induced by cyclophosphamide in rat fetuses

    PubMed Central

    Khaksary Mahabady, Mahmood; Gholami, Mohammad Reza; Najafzadeh Varzi, Hossein; Zendedel, Abolfazl; Doostizadeh, Mona

    2016-01-01

    Cyclophosphamide (CP) is a drug commonly used to treat neoplastic disease and some autoimmune diseases. It is also a well-known and well-studied teratogen causing a variety of birth defects in fetuses of pregnant women treated with the drug. There are many reports that show the adverse effects of CP can be decreased by use of antioxidant drugs. It appears that, quercetin has antioxidant effect. The aim of this study was prevention or decrease of teratogenicity of CP in fetuses of rats by quercetin. This study was performed on 35 pregnant rats divided into six groups. Control group was received normal saline (5 mL kg-1, intraperitoneally) and 2-6 groups received a single dose of CP (15 mg kg-1), a single dose of quercetin (75 or 200 mg kg-1), CP plus quercetin (75 or 200 mg kg-1) intraperitoneally at 9th day of gestation, respectively. Fetuses were collected at 20th day of gestation and after determination of weight and crown rump length were stained by alizarin red – alcian blue method and skeletal system were examined by stereomicroscope. The results showed that the cleft palate, exencephaly, spina bifida and omphalocele incidence were 55.56%, 27.77%, 33.34% and 11.11%, in fetuses of rat that received only CP, respectively. However, it decreased to 16.00%, 16.00%, 16.00% and 8.00% by quercetin (75 mg kg-1) and so to 12.90%, 12.90%, 6.45% and 3.28% by quercetin (200 mg kg-1), respectively. On the basis of results, quercetin significantly can decrease teratogenicity induced by CP. PMID:27482358

  19. Quercetin alleviates pulmonary angiogenesis in a rat model of hepatopulmonary syndrome.

    PubMed

    Li, X; Chen, Y; Wang, L; Shang, G; Zhang, C; Zhao, Z; Zhang, H; Liu, A

    2016-07-01

    Quercetin shows protective effects against hepatopulmonary syndrome (HPS), as demonstrated in a rat model. However, whether these effects involve pulmonary vascular angiogenesis in HPS remains unclear. Therefore, this study aimed to assess the effect of quercetin on pulmonary vascular angiogenesis and explore the underlying mechanisms. Male Sprague-Dawley rats weighing 200-250 g underwent sham operation or common bile duct ligation (CBDL). Two weeks after surgery, HIF-1α and NFκB levels were assessed in rat lung tissue by immunohistochemistry and western blot. Then, CBDL and sham-operated rats were further divided into 2 subgroups each to receive intraperitoneal administration of quercetin (50 mg/kg daily) or 0.2% Tween for two weeks: Sham (Sham+Tween; n=8), CBDL (CBDL+Tween; n=8), Q (Sham+quercetin; n=8), and CBDL+Q (CBDL+quercetin; n=8). After treatment, lung tissue specimens were assessed for protein (immunohistochemistry and western blot) and/or gene expression (quantitative real-time PCR) levels of relevant disease markers, including VEGFA, VEGFR2, Akt/p-Akt, HIF-1α, vWf, and IκB/p-IκB. Finally, arterial blood was analyzed for alveolar arterial oxygen pressure gradient (AaPO2). Two weeks after CBDL, HIF-1α expression in the lung decreased, but was gradually restored at four weeks. Treatment with quercetin did not significantly alter HIF-1α levels, but did reduce AaPO2 as well as lung tissue NF-κB activity, VEGFA gene and protein levels, Akt activity, and angiogenesis. Although hypoxia is an important feature in HPS, our findings suggest that HIF-1α was not the main cause for the VEGFA increase. Interestingly, quercetin inhibited pulmonary vascular angiogenesis in rats with HPS, with involvement of Akt/NF-κB and VEGFA/VEGFR-2 pathways. PMID:27383124

  20. Quercetin attenuates neuronal death against aluminum-induced neurodegeneration in the rat hippocampus.

    PubMed

    Sharma, D R; Wani, W Y; Sunkaria, A; Kandimalla, R J; Sharma, R K; Verma, D; Bal, A; Gill, K D

    2016-06-01

    Aluminum is a light weight and toxic metal present ubiquitously on earth, which has gained considerable attention due to its neurotoxic effects. It also has been linked ecologically and epidemiologically to several neurological disorders, including Alzheimer's disease (AD), Parkinson's disease (PD), Guamanian-Parkinsonian complex and Amyotrophic lateral sclerosis (ALS). The mechanism of aluminum neurotoxicity is poorly understood, but it is well documented that aluminum generates reactive oxygen species (ROS). Enhanced ROS production leads to disruption of cellular antioxidant defense systems and release of cytochrome c (cyt-c) from mitochondria to cytosol resulting in apoptotic cell death. Quercetin (a natural flavonoid) protects it from oxidative damage and has been shown to decrease mitochondrial damage in various animal models of oxidative stress. We hypothesized that if oxidative damage to mitochondria does play a significant role in aluminum-induced neurodegeneration, and then quercetin should ameliorate neuronal apoptosis. Administration of quercetin (10mg/kg body wt/day) reduced aluminum (10mg/kg body wt/day)-induced oxidative stress (decreased ROS production, increased mitochondrial superoxide dismutase (MnSOD) activity). In addition, quercetin also prevents aluminum-induced translocation of cyt-c, and up-regulates Bcl-2, down-regulates Bax, p53, caspase-3 activation and reduces DNA fragmentation. Quercetin also obstructs aluminum-induced neurodegenerative changes in aluminum-treated rats as seen by Hematoxylin and Eosin (H&E) staining. Further electron microscopic studies revealed that quercetin attenuates aluminum-induced mitochondrial swelling, loss of cristae and chromatin condensation. These results indicate that treatment with quercetin may represent a therapeutic strategy to attenuate the neuronal death against aluminum-induced neurodegeneration. PMID:26944603

  1. Protective effect of quercetin on skeletal and neural tube teratogenicity induced by cyclophosphamide in rat fetuses.

    PubMed

    Khaksary Mahabady, Mahmood; Gholami, Mohammad Reza; Najafzadeh Varzi, Hossein; Zendedel, Abolfazl; Doostizadeh, Mona

    2016-01-01

    Cyclophosphamide (CP) is a drug commonly used to treat neoplastic disease and some autoimmune diseases. It is also a well-known and well-studied teratogen causing a variety of birth defects in fetuses of pregnant women treated with the drug. There are many reports that show the adverse effects of CP can be decreased by use of antioxidant drugs. It appears that, quercetin has antioxidant effect. The aim of this study was prevention or decrease of teratogenicity of CP in fetuses of rats by quercetin. This study was performed on 35 pregnant rats divided into six groups. Control group was received normal saline (5 mL kg(-1), intraperitoneally) and 2-6 groups received a single dose of CP (15 mg kg(-1)), a single dose of quercetin (75 or 200 mg kg(-1)), CP plus quercetin (75 or 200 mg kg(-1)) intraperitoneally at 9(th) day of gestation, respectively. Fetuses were collected at 20(th) day of gestation and after determination of weight and crown rump length were stained by alizarin red - alcian blue method and skeletal system were examined by stereomicroscope. The results showed that the cleft palate, exencephaly, spina bifida and omphalocele incidence were 55.56%, 27.77%, 33.34% and 11.11%, in fetuses of rat that received only CP, respectively. However, it decreased to 16.00%, 16.00%, 16.00% and 8.00% by quercetin (75 mg kg(-1)) and so to 12.90%, 12.90%, 6.45% and 3.28% by quercetin (200 mg kg(-1)), respectively. On the basis of results, quercetin significantly can decrease teratogenicity induced by CP. PMID:27482358

  2. Pleiotropic Effects of Tocotrienols and Quercetin on Cellular Senescence: Introducing the Perspective of Senolytic Effects of Phytochemicals.

    PubMed

    Malavolta, Marco; Pierpaoli, Elisa; Giacconi, Robertina; Costarelli, Laura; Piacenza, Francesco; Basso, Andrea; Cardelli, Maurizio; Provinciali, Mauro

    2016-01-01

    The possibility to target cellular senescence with natural bioactive substances open interesting therapeutic perspective in cancer and aging. Engaging senescence response is suggested as a key component for therapeutic intervention in the eradication of cancer. At the same time, delaying senescence or even promote death of accumulating apoptosis-resistant senescent cells is proposed as a strategy to prevent age related diseases. Although these two desired outcome present an intrinsic dichotomy, there are examples of promising natural compounds that appear to satisfy all the requirements to develop senescence- targeted health promoting nutraceuticals. Tocotrienols (T3s) and quercetin (QUE), albeit belonging to different phytochemical classes, display similar and promising effects "in vitro" when tested in normal and cancer cells. Both compounds have been shown to induce senescence and promote apoptosis in a multitude of cancer lines. Conversely, they display senescence delaying activity in primary cells and rejuvenating effects in senescent cells. More recently, QUE has been shown to display senolytic effects in some primary senescent cells, likely as a consequence of its inhibitory effects on specific anti-apoptotic genes (i.e. PI3K and other kinases). Senolytic activity has not been tested for T3s but part of metabolic and apoptotic pathways affected by these compounds in cancer cells overlap with those of QUE. This suggests that the rejuvenating effects of T3s and QUE on pre-senescent and senescent primary cells might be the net results of a senolytic activity on senescent cells and a selective survival of a sub-population of non-senescent cells in the culture. The meaning of this hypothesis in the context of adjuvant therapy of cancer and preventive anti-aging strategies with QUE or T3s is discussed. PMID:26343116

  3. Quercetin downregulates Mcl-1 by acting on mRNA stability and protein degradation

    PubMed Central

    Spagnuolo, C; Cerella, C; Russo, M; Chateauvieux, S; Diederich, M; Russo, G L

    2011-01-01

    Background: We recently demonstrated that quercetin, a flavonoid naturally present in food and beverages belonging to the large class of phytochemicals, was able to sensitise leukaemic cells isolated from patients with chronic lymphocytic leukaemia (CLL) when associated with recombinant tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) or anti-CD95. We also showed that quercetin potentiated the effect of fludarabine on resistant B cells from CLL patients. Resistance to therapy in CLL depends on the expression and activity of anti-apoptotic proteins of the Bcl-2 family. Among these, myeloid cell leukaemia-1 (Mcl-1) has been associated with apoptotic resistance in CLL. Therefore, we investigate here whether the sensitising activity of this flavonoid, which leads to increased apoptosis in both cell lines and CLL, could be related to Mcl-1 expression and stability. Results: B cells isolated from CLL patients showed different levels of Mcl-1 protein expression, resulting, in several cases, in increased sensitivity to fludarabine. Quercetin significantly enhanced the downregulation of Mcl-1 in B cells isolated from selected patients expressing detectable levels of Mcl-1. In U-937 cells, quercetin increased Mcl-1 mRNA instability in the presence of actinomycin D. When cells were treated with MG-132, a proteasome inhibitor, Mcl-1 protein level increased. However, quercetin, in the presence of Z-Vad-FMK, continued to lower Mcl-1 protein expression, indicating its independence from caspase-mediated degradation. In contrast, co-treatment of quercetin and MG-132 did not revert the effect of MG-132 mono-treatment, thus suggesting a possible interference of quercetin in regulating the proteasome-dependent degradation of Mcl-1. Gossypol, a small-molecule inhibitor of Bcl-2 family members, mimics the activity of quercetin by lowering Mcl-1 expression and sensitising U-937 cells to apoptosis induced by recombinant TRAIL and the Fas-ligand. Conclusion: This study

  4. Biological impacts of resveratrol, quercetin, and N-acetylcysteine on oxidative stress in human gingival fibroblasts.

    PubMed

    Orihuela-Campos, Rita Cristina; Tamaki, Naofumi; Mukai, Rie; Fukui, Makoto; Miki, Kaname; Terao, Junji; Ito, Hiro-O

    2015-05-01

    In periodontitis, production of reactive oxygen species (ROS) by neutrophils induces oxidative stress and deteriorates surrounding tissues. Antioxidants reduce damage caused by ROS and are used to treat diseases involving oxidative stress. This study summarizes the different effects of resveratrol, quercetin, and N-acetylcysteine (NAC) on human gingival fibroblasts (HGFs) under oxidative stress induced by hydrogen peroxide. Real-time cytotoxicity analyses reveals that resveratrol and quercetin enhanced cell proliferation even under oxidative stress. Of the antioxidants tested, resveratrol is the most effective at inhibiting ROS production. HGFs incubated with resveratrol and quercetin up-regulate the transcription of type I collagen gene after 3 h, but only resveratrol sustained this up-regulation for 24 h. A measurement of the oxygen consumption rate (OCR, mitochondrial respiration) shows that resveratrol generates the highest maximal respiratory capacity, followed by quercetin and NAC. Simultaneous measurement of OCR and the extracellular acidification rate (non-mitochondrial respiration) reveals that resveratrol and quercetin induce an increase in mitochondrial respiration when compared with untreated cells. NAC treatment consumes less oxygen and enhances more non-mitochondrial respiration. In conclusion, resveratrol is the most effective antioxidant in terms of real-time cytotoxicity analysis, reduction of ROS production, and enhancement of type I collagen synthesis and mitochondrial respiration in HGFs. PMID:26060353

  5. Biological impacts of resveratrol, quercetin, and N-acetylcysteine on oxidative stress in human gingival fibroblasts

    PubMed Central

    Orihuela-Campos, Rita Cristina; Tamaki, Naofumi; Mukai, Rie; Fukui, Makoto; Miki, Kaname; Terao, Junji; Ito, Hiro-O

    2015-01-01

    In periodontitis, production of reactive oxygen species (ROS) by neutrophils induces oxidative stress and deteriorates surrounding tissues. Antioxidants reduce damage caused by ROS and are used to treat diseases involving oxidative stress. This study summarizes the different effects of resveratrol, quercetin, and N-acetylcysteine (NAC) on human gingival fibroblasts (HGFs) under oxidative stress induced by hydrogen peroxide. Real-time cytotoxicity analyses reveals that resveratrol and quercetin enhanced cell proliferation even under oxidative stress. Of the antioxidants tested, resveratrol is the most effective at inhibiting ROS production. HGFs incubated with resveratrol and quercetin up-regulate the transcription of type I collagen gene after 3 h, but only resveratrol sustained this up-regulation for 24 h. A measurement of the oxygen consumption rate (OCR, mitochondrial respiration) shows that resveratrol generates the highest maximal respiratory capacity, followed by quercetin and NAC. Simultaneous measurement of OCR and the extracellular acidification rate (non-mitochondrial respiration) reveals that resveratrol and quercetin induce an increase in mitochondrial respiration when compared with untreated cells. NAC treatment consumes less oxygen and enhances more non-mitochondrial respiration. In conclusion, resveratrol is the most effective antioxidant in terms of real-time cytotoxicity analysis, reduction of ROS production, and enhancement of type I collagen synthesis and mitochondrial respiration in HGFs. PMID:26060353

  6. Quercetin Impacts Expression of Metabolism- and Obesity-Associated Genes in SGBS Adipocytes.

    PubMed

    Leiherer, Andreas; Stoemmer, Kathrin; Muendlein, Axel; Saely, Christoph H; Kinz, Elena; Brandtner, Eva M; Fraunberger, Peter; Drexel, Heinz

    2016-01-01

    Obesity is characterized by the rapid expansion of visceral adipose tissue, resulting in a hypoxic environment in adipose tissue which leads to a profound change of gene expression in adipocytes. As a consequence, there is a dysregulation of metabolism and adipokine secretion in adipose tissue leading to the development of systemic inflammation and finally resulting in the onset of metabolic diseases. The flavonoid quercetin as well as other secondary plant metabolites also referred to as phytochemicals have anti-oxidant, anti-inflammatory, and anti-diabetic effects known to be protective in view of obesity-related-diseases. Nevertheless, its underlying molecular mechanism is still obscure and thus the focus of this study was to explore the influence of quercetin on human SGBS (Simpson Golabi Behmel Syndrome) adipocytes' gene expression. We revealed for the first time that quercetin significantly changed expression of adipokine (Angptl4, adipsin, irisin and PAI-1) and glycolysis-involved (ENO2, PFKP and PFKFB4) genes, and that this effect not only antagonized but in part even overcompensated the effect mediated by hypoxia in adipocytes. Thus, these results are explained by the recently proposed hypothesis that the protective effect of quercetin is not solely due to its free radical-scavenging activity but also to a direct effect on mitochondrial processes, and they demonstrate that quercetin might have the potential to counteract the development of obesity-associated complications. PMID:27187453

  7. Quercetin Preventive Effects on Theophylline-Induced Anomalies in Rat Embryo

    PubMed Central

    Sistani Karampour, Neda; Arzi, Ardeshir; Najafzadeh Varzi, Hossein; Mohammadian, Babak; Rezaei, Mohsen

    2014-01-01

    Background: Theophylline has been shown to cause heart anomaly in animal and human fetus. Objectives: The present study aimed to investigate the protective effect of quercetin on theophylline-induced heart disorders in rat embryo. Materials and Methods: Theophylline-induced teratogenicity in rats was used as the animal model. Pregnant rats were administered theophylline (259 mg/kg, po) or theophylline plus quercetin (259 mg/kg, po and 100 mg/kg, ip, respectively) on 9th and 10th days of pregnancy. On day 19, cardiac changes were assessed, measuring malondialdehyde (MDA) and glutathione peroxidase (GPx) activity levels in blood samples and also the fetus heart weight. Histopathological examination was also performed on all specimens. Results: Theophylline-treated rats showed MDA level elevation and GPx activity reduction. Quercetin treatment improved heart conditions and resulted in a significant reduction in MDA levels and elevation in GPx activity. Moreover, co-administration of quercetin and theophylline increased the heart weight significantly. Furthermore, histophatological study showed no changes in the treated groups. Conclusions: This study demonstrated that quercetin have beneficial effects on theophylline-induced-anomalies in rat embryo. PMID:25237647

  8. Synergy and Mode of Action of Ceftazidime plus Quercetin or Luteolin on Streptococcus pyogenes

    PubMed Central

    Siriwong, Supatcharee; Thumanu, Kanjana; Hengpratom, Tanaporn; Eumkeb, Griangsak

    2015-01-01

    Streptococcus pyogenes causes streptococcal toxic shock syndrome. The recommended therapy has been often failure through the interfering of beta-lactamase-producing bacteria (BLPB). The present study was to investigate antibacterial activity, synergy, and modes of action of luteolin and quercetin using alone and plus ceftazidime against S. pyogenes. The MICs of ceftazidime, luteolin, and quercetin against all S. pyogenes were 0.50, 128, and 128 µg mL−1, respectively. A synergistic effect was exhibited on luteolin and quercetin plus ceftazidime against these strains at fractional inhibitory concentration indices 0.37 and 0.27, respectively, and was confirmed by the viable count. These combinations increased cytoplasmic membrane (CM) permeability, caused irregular cell shape, peptidoglycan, and CM damage, and decreased nucleic acid but increased proteins in bacterial cells. Enzyme assay demonstrated that these flavonoids had an inhibitory activity against β-lactamase. In summary, this study provides evidence that the inhibitory mode of action of luteolin and quercetin may be mediated via three mechanisms: (1) inhibiting of peptidoglycan synthesis, (2) increasing CM permeability, and (3) decreasing nucleic acid but increasing the protein contents of bacterial cells. So, luteolin and quercetin propose the high potential to develop adjunct to ceftazidime for the treatment of coexistence of the BLPB and S. pyogenes infections. PMID:26576195

  9. Mesoporous silica as topical nanocarriers for quercetin: characterization and in vitro studies.

    PubMed

    Sapino, Simona; Ugazio, Elena; Gastaldi, Lucia; Miletto, Ivana; Berlier, Gloria; Zonari, Daniele; Oliaro-Bosso, Simonetta

    2015-01-01

    The flavonoid quercetin is extensively studied for its antioxidant and chemopreventive properties. However the poor water-solubility, low stability and short half-life could restrict its use in skin care products and therapy. The present study was aimed to evaluate the potential of aminopropyl functionalized mesoporous silica nanoparticles (NH2-MSN) as topical carrier system for quercetin delivery. Thermo gravimetric analysis, X-ray diffraction, high resolution transmission electron microscopy, nitrogen adsorption isotherms, FT-IR spectroscopy, zeta potential measurements and differential scanning calorimetry allowed analyzing with great detail the organic-inorganic molecular interaction. The protective effect of this vehicle on UV-induced degradation of the flavonoid was investigated revealing a certain positive influence of the inclusion on the photostability over time. Epidermal accumulation and transdermal permeation of this molecule were ex vivo evaluated using porcine skin mounted on Franz diffusion cells. The inclusion complexation with the inorganic nanoparticles increased the penetration of quercetin into the skin after 24h post-application without transdermal delivery. The effect of quercetin alone or given as complex with NH2-MSN on proliferation of JR8 human melanoma cells was evaluated by sulforhodamine B colorimetric proliferation assay. At a concentration 60 μM the complex with NH2-MSN was more effective than quercetin alone, causing about 50% inhibition of cell proliferation. PMID:25478737

  10. Hyaluronic acid-quercetin conjugate micelles: synthesis, characterization, in vitro and in vivo evaluation.

    PubMed

    Pang, Xin; Lu, Zhen; Du, Hongliang; Yang, Xiaoye; Zhai, Guangxi

    2014-11-01

    A tumor cell-targeted prodrug was developed for quercetin, using hyaluronic acid as polymeric carrier. Hyaluronic acid-quercetin (HA-QT) bioconjugates were synthesized by linking the hydroxy of quercetin via a succinate ester to adipic dihydrazide-modified hyaluronic acid. The mirco-morphology demonstrated that the prepared prodrug could form self-assembled micelles possessing spherical shape, 172.1 nm average diameter and -20.30 mV surface potential. The HA-QT micelles exhibited significant sustained and pH-dependent drug release behaviors without dramatic initial burst. Compared to free quercetin solution, the HA-QT micelles were found a 4 times increase in cytotoxicity on MCF-7 cells (CD44-overexpressing cell lines), while weak enhancement in inhibitory activity was observed towards L929 cells (CD44 deficient cell lines). Promisingly, 20.1-fold increase in the half-life and 4.9-fold increase in the area-under-the-curve (AUC) of quercetin were achieved for the HA-QT micelles compared with the parent drug. In addition, the HA-QT micelles also showed excellent inhibition effect on tumor growth in H22 tumor-bearing mice. Hemolytic toxicity and vein irritation assay further suggested that the HA-QT micelles were a safe and potent drug delivery system for targeted antitumor therapy. PMID:25454664

  11. Different mechanisms of actions of genistein, quercetin on spontaneous contractions of rabbit duodenum.

    PubMed

    Santos-Fagundes, Diego; Grasa, Laura; Gonzalo, Sergio; Valero, Marta Sofía; Castro, Marta; Arruebo, María Pilar; Plaza, Miguel Ángel; Divina-Murillo, María

    2015-07-01

    Flavonoids are known to relax precontracted intestinal smooth muscle and delay intestinal transit or intestinal peristalsis. The aim of this study was to determine the effects of genistein and quercetin on spontaneous contractions of rabbit duodenum in vitro in an organ bath. Genistein and quercetin (0.1-10µM) reduced the amplitude of spontaneous contractions in the longitudinal and circular smooth muscle of rabbit duodenum, but they did not modify the frequency. Bay K8644 (L-type Ca2+ channel activator), apamin, charybdotoxin, and tetraetylammonium (K+ channel blockers) reverted the inhibition of amplitude of spontaneous contractions induced by genistein in longitudinal and circular smooth muscle. H-89 (protein kinase A inhibitor) antagonized the reduction of the amplitude of spontaneous contractions induced by quercetin in longitudinal and circular smooth muscle of duodenum, while 2,5-dideoxiadenosine (adenylyl cyclase inhibitor) reverted only the reduction of the amplitude in circular smooth muscle. In conclusion, genistein and quercetin reduce the spontaneous contractions in the duodenum by different mechanisms of actions. The effect of genistein would be mediated by Ca2+ and K+ channels, while the effect of quercetin would be mediated by cAMP and protein kinase A. PMID:26140633

  12. Permeation and skin retention of quercetin from microemulsions containing Transcutol® P.

    PubMed

    Censi, Roberta; Martena, Valentina; Hoti, Ela; Malaj, Ledjan; Di Martino, Piera

    2012-09-01

    A microemulsion for the cutaneous release of quercetin was prepared. An aqueous phase, containing 40% Transcutol® P as solubilizing agent and permeation enhancer, was emulsified with Labrafil® as oil phase and Labrasol®/Capryol™ 90 as Solvent/Co-solvent. Quercetin was dissolved in the microemulsion at the concentration of 1%. Ternary phase diagrams were generated to determine the optimal concentration of each excipient composing the microemulsion. The physicochemical properties of the microemulsion, such as pH, viscosity, refractive index, and particle size distribution were determined. The microemulsion was stable for 12 months at the storing conditions of 25.0 ± 1.0°C. The in vitro quercetin permeability into and through the abdominal hairless pig skin was determined by vertical Franz's cells. Quercetin showed hardly any permeability through the skin when dissolved in water- and Transcutol® P-free media, whereas a remarkable increase in cutaneous permeability was observed when quercetin was formulated in the microemulsion or when simply dissolved in Transcutol® P. These two last formulations are those showing the lower skin retention. PMID:22188183

  13. Ochratoxin-induced toxicity, oxidative stress and apoptosis ameliorated by quercetin--modulation by Nrf2.

    PubMed

    Ramyaa, Periasamy; Padma, Viswanadha Vijaya

    2013-12-01

    Ochratoxin (OTA) is one of the most abundant food contaminating mycotoxins and is commonly present in the food chain. Many of the effects associated with OTA, appear to be mediated through oxidative stress. Although the toxicity of OTA is fairly well characterized, antidotes for alleviating the toxicity are sparsely reported. Dietary antioxidants have gained much importance in the recent years for their antioxidative and therapeutic properties. In the present study the therapeutic strategy was directed towards use of quercetin, a dietary antioxidant to combat OTA-induced toxicity in Vero cell line. Our results demonstrate that quercetin pre-treatment suppressed OTA-induced cytotoxicity and oxidative stress. It modulated OTA-induced alteration on the antioxidant defence through activation of Nrf2 pathway. Morphological studies by scanning electron microscopy (SEM) and cell cycle analysis indicated that quercetin prevented OTA-induced apoptosis. It also inhibited the activation of caspase cascade that leads to DNA fragmentation. Quercetin also exhibited antigenotoxic potential by attenuating OTA-induced DNA damage and micronucleus (MN) formation. The results of the study demonstrate for the first time that quercetin pre-treatment prevents OTA-induced oxidative stress and apoptosis in Vero cell line. PMID:23994659

  14. Quercetin ameliorates polychlorinated biphenyls-induced testicular DNA damage in rats.

    PubMed

    Lovato, F L; de Oliveira, C R; Adedara, I A; Barbisan, F; Moreira, K L S; Dalberto, M; da Rocha, M I U M; Marroni, N P; da Cruz, I B; Costabeber, I B

    2016-02-01

    Polychlorinated biphenyls (PCBs) are a group of environmental contaminants widely reported to cause gonadal toxicity in both humans and animals. This study investigated the amelioratory role of quercetin in PCBs-induced DNA damage in male Wistar rats. Polychlorinated biphenyls were administered intraperitoneally at a dose of 2 mg kg(-1) alone or in combination with quercetin (orally) at 50 mg kg(-1) for 25 days. Quercetin modulation of PCBs-induced gonadal toxicity was evaluated using selected oxidative stress indices, comet assay, measurement of DNA concentration and histology of the testes. Administration of PCBs alone caused a significant (P < 0.05) depletion in the total thiol level in testes of treated rats. Conversely, the levels of reactive oxygen species (ROS) and thiobarbituric acid reactive substances (TBARS) production were markedly elevated in testes of PCBs-treated rats compared with control. Further, PCBs exposure produced statistically significant increases in DNA tail migration, degraded double-stranded DNA (dsDNA) concentration and histological alterations of testes of the treated rats compared to control. Quercetin cotreatment significantly improved the testicular antioxidant status, decreased DNA fragmentation and restored the testicular histology, thus demonstrating the protective effect of quercetin in PCBs-treated rats. PMID:25892208

  15. Quercetin Impacts Expression of Metabolism- and Obesity-Associated Genes in SGBS Adipocytes

    PubMed Central

    Leiherer, Andreas; Stoemmer, Kathrin; Muendlein, Axel; Saely, Christoph H.; Kinz, Elena; Brandtner, Eva M.; Fraunberger, Peter; Drexel, Heinz

    2016-01-01

    Obesity is characterized by the rapid expansion of visceral adipose tissue, resulting in a hypoxic environment in adipose tissue which leads to a profound change of gene expression in adipocytes. As a consequence, there is a dysregulation of metabolism and adipokine secretion in adipose tissue leading to the development of systemic inflammation and finally resulting in the onset of metabolic diseases. The flavonoid quercetin as well as other secondary plant metabolites also referred to as phytochemicals have anti-oxidant, anti-inflammatory, and anti-diabetic effects known to be protective in view of obesity-related-diseases. Nevertheless, its underlying molecular mechanism is still obscure and thus the focus of this study was to explore the influence of quercetin on human SGBS (Simpson Golabi Behmel Syndrome) adipocytes’ gene expression. We revealed for the first time that quercetin significantly changed expression of adipokine (Angptl4, adipsin, irisin and PAI-1) and glycolysis-involved (ENO2, PFKP and PFKFB4) genes, and that this effect not only antagonized but in part even overcompensated the effect mediated by hypoxia in adipocytes. Thus, these results are explained by the recently proposed hypothesis that the protective effect of quercetin is not solely due to its free radical-scavenging activity but also to a direct effect on mitochondrial processes, and they demonstrate that quercetin might have the potential to counteract the development of obesity-associated complications. PMID:27187453

  16. Novel quercetin-3-O-glucoside eicosapentaenoic acid ester ameliorates inflammation and hyperlipidemia.

    PubMed

    Sekhon-Loodu, Satvir; Ziaullah, Ziaullah; Rupasinghe, H P Vasantha; Wang, Yanwen; Kulka, Marianna; Shahidi, Fereidoon

    2015-08-01

    Quercetin, a major flavonol, present abundantly in apples and onions, is widely studied for ameliorating metabolic syndrome abnormalities. However, quercetin is mainly present in plant food in the form of quercetin glycosides and has been reported for poor gastrointestinal absorption. The present study was designed with the purpose of imparting a lipophilic property to quercetin-3-O-glucoside (QG) by its acylation with eicosapentaenoic acid (EPA) and to study the influence of eicosapentaenoic acid ester of quercetin-3-O-glucoside (QE) on hyperlipidemia and inflammation in vivo and in vitro. QE was more effective in reducing the production of tumor necrosis factor-alpha (TNF-α), prostaglandin 2 (PGE2), cyclo-oxygenase (COX)-2 levels and nuclear expression of nuclear factor-kappa B (NF-кB) compared to the parent compounds (QG and EPA) and commercial drugs, after lipopolysaccharides (LPS) induced inflammation in THP-1 derived macrophages. Serum high-density lipoprotein (HDL)-cholesterol was significantly higher and hepatic total cholesterol concentration was lower in the rats fed high-fat diet supplemented with QE, compared to the high-fat diet with inflammation (HFL). The serum concentrations of C-reactive protein (CRP), interleukin (IL)-6, and interferon-gamma (IFN-γ) were significantly lower in QE treatment group than HFL group. EPA conjugated flavonol, QE, had significant anti-inflammatory and hypolipidemic properties and may be effective for the treatment of obesity-related disorders. PMID:26165697

  17. Quercetin Attenuates Chronic Ethanol-Induced Hepatic Mitochondrial Damage through Enhanced Mitophagy

    PubMed Central

    Yu, Xiao; Xu, Yanyan; Zhang, Shanshan; Sun, Jian; Liu, Peiyi; Xiao, Lin; Tang, Yuhan; Liu, Liegang; Yao, Ping

    2016-01-01

    Emerging evidence suggested mitophagy activation mitigates ethanol-induced liver injury. However, the effect of ethanol on mitophagy is inconsistent. Importantly, the understanding of mitophagy status after chronic ethanol consumption is limited. This study evaluated the effect of quercetin, a naturally-occurring flavonoid, on chronic ethanol-induced mitochondrial damage focused on mitophagy. An ethanol regime to mice for 15 weeks (accounting for 30% of total calories) led to significant mitochondrial damage as evidenced by changes of the mitochondrial ultrastructure, loss of mitochondrial membrane potential and remodeling of membrane lipid composition, which was greatly attenuated by quercetin (100 mg/kg.bw). Moreover, quercetin blocked chronic ethanol-induced mitophagy suppression as denoted by mitophagosomes-lysosome fusion and mitophagy-related regulator elements, including LC3II, Parkin, p62 and voltage-dependent anion channel 1 (VDAC1), paralleling with increased FoxO3a nuclear translocation. AMP-activated protein kinase (AMPK) and extracellular signal regulated kinase 2 (ERK2), instead of AKT and Sirtuin 1, were involved in quercetin-mediated mitophagy activation. Quercetin alleviated ethanol-elicited mitochondrial damage through enhancing mitophagy, highlighting a promising preventive strategy for alcoholic liver disease. PMID:26742072

  18. Redox reactions obtained by gamma irradiation of quercetin methanol solution are similar to in vivo metabolism.

    PubMed

    Marfak, A; Trouillas, P; Allais, D P; Calliste, C A; Duroux, J L

    2003-02-01

    The flavonol quercetin is one of the most well-known antioxidant flavonoids. Its antioxidant potential has been studied extensively during the last 10 years, but little is known about the metabolites formed in vivo that lead to the formation of depside and small molecules such as benzoic acids. In this study, gamma irradiation of a quercetin methanol solution was used as a model of certain oxidative reactions that occur in vivo. Qercetin at concentrations ranging from 5 x 10(-5) M to 5 x 10(-3) M, was irradiated with gamma rays at doses of 2-14 kGy. Quercetin degradation was evaluated by HPLC analysis. The major radiolytic metabolite was identified as a depside by NMR and LC-MS. Formation of 3,4-dihydroxybenzoic acid was also observed. The presence of CH3O. formed during methanol radiolysis is invoked to explain depside formation. Transformation of the 8-methoxy substituted depside (Q1) to the 8-hydroxyl substituted depside (Q2) is discussed. The antioxidant properties of quercetin metabolites are evaluated according to their capacity to decrease the EPR DPPH signal and to inhibit superoxide radical formed by the enzymatic reaction (xanthine + xanthine oxidase). For both assays, the IC50 of Q2 is twice as high as that of quercetin. PMID:12537527

  19. Quercetin and its principal metabolites, but not myricetin, oppose lipopolysaccharide-induced hyporesponsiveness of the porcine isolated coronary artery

    PubMed Central

    Al-Shalmani, Salmin; Suri, Sunita; Hughes, David A; Kroon, Paul A; Needs, Paul W; Taylor, Moira A; Tribolo, Sandra; Wilson, Vincent G

    2011-01-01

    BACKGROUND AND PURPOSE Quercetin is anti-inflammatory in macrophages by inhibiting lipopolysaccharide (LPS)-mediated increases in cytokine and nitric oxide production but there is little information regarding the corresponding effect on the vasculature. We have examined the effect of quercetin, and its principal human metabolites, on inflammatory changes in the porcine isolated coronary artery. EXPERIMENTAL APPROACH Porcine coronary artery segments were incubated overnight at 37°C in modified Krebs-Henseleit solution with or without 1 µg·mL−1 LPS. Some segments were also co-incubated with quercetin-related flavonoids or Bay 11-7082, an inhibitor of NFκB. Changes in isometric tension of segments to vasoconstrictor and vasodilator agents were recorded. Nitrite content of the incubation solution was estimated using the Griess reaction, while inducible nitric oxide synthase was identified immunohistochemically. KEY RESULTS Lipopolysaccharide reduced, by 35–50%, maximal contractions to KCl and U46619, thromboxane A2 receptor agonist, and impaired endothelium-dependent relaxations to substance P. Nitrite content of the incubation medium increased 3- to 10-fold following exposure to LPS and inducible nitric oxide synthase was detected in the adventitia. Quercetin (0.1–10 µM) opposed LPS-induced changes in vascular responses, nitrite production and expression of inducible nitric oxide synthase. Similarly, 10 µM Bay 11-7082, 10 µM quercetin 3′-sulphate and 10 µM quercetin 3-glucuronide prevented LPS-induced changes, while myricetin (10 µM) was inactive. Myricetin (10 µM) prevented quercetin-induced modulation of LPS-mediated nitrite production. CONCLUSION AND IMPLICATIONS Quercetin, quercetin 3′-suphate and quercetin 3-glucuronide, exerted anti-inflammatory effects on the vasculature, possibly through a mechanism involving inhibition of NFκB. Myricetin-induced antagonism of the effect of anti-inflammatory action of quercetin merits further investigation

  20. Quercetin regulates hepatic cholesterol metabolism by promoting cholesterol-to-bile acid conversion and cholesterol efflux in rats.

    PubMed

    Zhang, Min; Xie, Zongkai; Gao, Weina; Pu, Lingling; Wei, Jingyu; Guo, Changjiang

    2016-03-01

    Quercetin, a common member of the flavonoid family, is widely present in plant kingdom. Despite that quercetin is implicated in regulating cholesterol metabolism, the molecular mechanism is poorly understood. We hypothesized that quercetin regulates cholesterol homeostasis through regulating the key enzymes involved in hepatic cholesterol metabolism. To test this hypothesis, we compared the profile of key enzymes and transcription factors involved in the hepatic cholesterol metabolism in rats with or without quercetin supplementation. Twenty male Wistar rats were randomly divided into control and quercetin-supplemented groups. Serum total cholesterol, triglyceride, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and total bile acids in feces and bile were measured. Hepatic enzymatic activities were determined by activity assay kit and high-performance liquid chromatography-based analyses. The messenger RNA (mRNA) and protein expressions were determined by reverse transcriptase polymerase chain reaction and Western blot analyses, respectively. The results showed that the activity of hepatic cholesterol 7α-hydroxylase, a critical enzyme in the conversion of cholesterol to bile acids, was significantly elevated by quercetin. The expression of cholesterol 7α-hydroxylase, as well as liver X receptor α, an important transcription factor, was also increased at both mRNA and protein levels by quercetin. However, quercetin exposure had no impact on the activity of hepatic HMG-CoA reductase, a rate-limiting enzyme in the biosynthesis of cholesterol. We also found that quercetin treatment significantly increased ATP binding cassette transporter G1 mRNA and protein expression in the liver, suggesting that quercetin may increase hepatic cholesterol efflux. Collectively, the results presented here indicate that quercetin regulates hepatic cholesterol metabolism mainly through the pathways that promote cholesterol-to-bile acid conversion and

  1. The diversity of nanos expression in echinoderm embryos supports different mechanisms in germ cell specification.

    PubMed

    Fresques, Tara; Swartz, Steven Zachary; Juliano, Celina; Morino, Yoshiaki; Kikuchi, Mani; Akasaka, Koji; Wada, Hiroshi; Yajima, Mamiko; Wessel, Gary M

    2016-07-01

    Specification of the germ cell lineage is required for sexual reproduction in all animals. However, the timing and mechanisms of germ cell specification is remarkably diverse in animal development. Echinoderms, such as sea urchins and sea stars, are excellent model systems to study the molecular and cellular mechanisms that contribute to germ cell specification. In several echinoderm embryos tested, the germ cell factor Vasa accumulates broadly during early development and is restricted after gastrulation to cells that contribute to the germ cell lineage. In the sea urchin, however, the germ cell factor Vasa is restricted to a specific lineage by the 32-cell stage. We therefore hypothesized that the germ cell specification program in the sea urchin/Euechinoid lineage has evolved to an earlier developmental time point. To test this hypothesis we determined the expression pattern of a second germ cell factor, Nanos, in four out of five extant echinoderm clades. Here we find that Nanos mRNA does not accumulate until the blastula stage or later during the development of all other echinoderm embryos except those that belong to the Echinoid lineage. Instead, Nanos is expressed in a restricted domain at the 32-128 cell stage in Echinoid embryos. Our results support the model that the germ cell specification program underwent a heterochronic shift in the Echinoid lineage. A comparison of Echinoid and non-Echinoid germ cell specification mechanisms will contribute to our understanding of how these mechanisms have changed during animal evolution. PMID:27402572

  2. Synergistic effects of snail and quercetin on renal cell carcinoma Caki-2 by altering AKT/mTOR/ERK1/2 signaling pathways

    PubMed Central

    Meng, Fan-Dong; Li, Yan; Tian, Xin; Ma, Ping; Sui, Cheng-Guang; Fu, Li-Ye; Jiang, You-Hong

    2015-01-01

    Renal cell carcinoma has become the most common subtype of kidney cancer, and has the highest propensity to manifest as metastatic disease. Because of lack of knowledge in events that correlated with tumor cell migration and invasion, few therapeutic options are available. Therefore, in current study, we explore the anti-tumoral effect of a potential chemopreventive natural product, quercetin, combined with anti-sense oligo gene therapy (inhibiting Snail gene). We found that either one of them had the remarkable effects in suppressing cell proliferation and migration, inducing cell cycle arrest and apoptosis in a ccRCC cell line, Caki-2 cells. The combination of both means provides even strong suppressive effects toward these ccRCC cells. Our study, for the first time, provides the possibility of using a novel treatment for renal cancer, by combining natural product and gene therapy. PMID:26261493

  3. Pharmacophore model of the quercetin binding site of the SIRT6 protein.

    PubMed

    Ravichandran, S; Singh, N; Donnelly, D; Migliore, M; Johnson, P; Fishwick, C; Luke, B T; Martin, B; Maudsley, S; Fugmann, S D; Moaddel, R

    2014-04-01

    SIRT6 is a histone deacetylase that has been proposed as a potential therapeutic target for metabolic disorders and the prevention of age-associated diseases. We have previously reported on the identification of quercetin and vitexin as SIRT6 inhibitors, and studied structurally related flavonoids including luteolin, kaempferol, apigenin and naringenin. It was determined that the SIRT6 protein remained active after immobilization and that a single frontal displacement could correctly predict the functional activity of the immobilized enzyme. The previous study generated a preliminary pharmacophore for the quercetin binding site on SIRT6, containing 3 hydrogen bond donors and one hydrogen bond acceptor. In this study, we have generated a refined pharmacophore with an additional twelve quercetin analogs. The resulting model had a positive linear behavior between the experimental elution time verses the fit values obtained from the model with a correlation coefficient of 0.8456. PMID:24491483

  4. Efficient regioselective acylation of quercetin using Rhizopus oryzae lipase and its potential as antioxidant.

    PubMed

    Kumar, Vinod; Jahan, Firdaus; Mahajan, Richi V; Saxena, Rajendra Kumar

    2016-10-01

    The present investigation describes the regioselective enzymatic acylation of quercetin with ferulic acid using Rhizopus oryzae lipase. Optimization of reaction parameters resulted in 93.2% yield of the ester synthesized using 750IU of lipase in cyclo-octane at a temperature of 45°C. The reaction was successfully carried out upto 25g scale. The ester synthesized was analyzed by (1)H Nuclear magnetic resonance spectroscopy. The ester synthesized (quercetin ferulate) showed higher antiradical activity as compared to ascorbic acid using the 2,2-diphenyl-1-picrylhydrazyl radical method. These results on enzyme-catalyzed acylation of quercetin might be used to prepare and scale-up other flavonoids derivatives. PMID:27372535

  5. Quercetin nanocomposite as novel anticancer therapeutic: improved efficiency and reduced toxicity.

    PubMed

    Cirillo, Giuseppe; Vittorio, Orazio; Hampel, Silke; Iemma, Francesca; Parchi, Paolo; Cecchini, Marco; Puoci, Francesco; Picci, Nevio

    2013-06-14

    A three-functional nanocomposite was prepared by radical polymerization of methacrylic acid around carbon nanotubes in the presence of Quercetin as biologically active molecule and proposed as new anticancer therapeutic. The so-obtained hybrid material was characterized by FT-IR, Raman, SEM, TEM analyses, while the functionalization degree of 2.33 mg of Quercetin per g of composite was assessed by Folin-Ciocalteu test. Antioxidant test (DPPH and ABTS) showed that the covalent coupling did not interfere with the antioxidant properties of the flavonoid, while the anticancer activity was greatly enhanced with a recorded IC50 value much lower than free Quercetin. Cell viability tests on healthy cells demonstrated no-toxicity of the conjugate. PMID:23602995

  6. Pharmacophore model of the quercetin binding site of the SIRT6 protein

    PubMed Central

    Ravichandran, S.; Singh, N.; Donnelly, D.; Migliore, M.; Johnson, P.; Fishwick, C.; Luke, Brian T.; Martin, B.; Maudsley, S.; Fugmann, S. D.; Moaddel, R.

    2014-01-01

    SIRT6 is a histone deacetylase that has been proposed as a potential therapeutic target for metabolic disorders and the prevention of age-associated diseases. We have previously reported on the identification of quercetin and vitexin as SIRT6 inhibitors, and studied structurally related flavonoids including luteolin, kaempferol, apigenin and naringenin. It was determined that the SIRT6 protein remained active after immobilization and that a single frontal displacement could correctly predict the functional activity of the immobilized enzyme. The previous study generated a preliminary pharmacophore for the quercetin binding site on SIRT6, containing 3 hydrogen bond donors and one hydrogen bond acceptor. In this study, we have generated a refined pharmacophore with an additional twelve quercetin analogs. The resulting model had a positive linear behavior between the experimental elution time verses the fit values obtained from the model with a correlation coefficient of 0.8456. PMID:24491483

  7. Relaxation behavior and nonlinear properties of thermally stable polymers based on glycidyl derivatives of quercetin

    NASA Astrophysics Data System (ADS)

    Mishurov, Dmytro; Voronkin, Andrii; Roshal, Alexander; Brovko, Oleksandr

    2016-07-01

    Cross-linked polymers on the basis of di-, tri and tetraglycidyl ethers of quercetin (3,3‧,4‧,5,7-pentahydroxyflavone) were synthesized, and then, poled in electrical field of corona discharge. Investigations of structural, thermal and optical parameters of the polymer films were carried out. It was found that the polymers obtained from di- and triglycidyl quercetin ethers had high values of macroscopic quadratic susceptibilities and substantial stability of nonlinear optical (NLO) properties after the poling. Tetraglycidyl ether of quercetin forms the polymer of lower quadratic susceptibility, which demonstrates noticeable relaxation process resulting in decrease of the NLO effect. It is supposed that the difference of the NLO properties is due to peculiarities of physical network of the polymers, namely to the ratio between numbers of hydrogen bonds formed by hydroxyl groups of chromophore fragments and by the ones of interfragmental parts of the polymeric chains.

  8. Solid dispersion of quercetin in cellulose derivative matrices influences both solubility and stability.

    PubMed

    Li, Bin; Konecke, Stephanie; Harich, Kim; Wegiel, Lindsay; Taylor, Lynne S; Edgar, Kevin J

    2013-02-15

    Amorphous solid dispersions (ASD) of quercetin (Que) in cellulose derivative matrices, carboxymethylcellulose acetate butyrate (CMCAB), hydroxypropylmethylcellulose acetate succinate (HPMCAS), and cellulose acetate adipate propionate (CAAdP) were prepared with the goal of identifying an ASD that effectively increased Que aqueous solution concentration. Crystalline quercetin and Que/poly(vinylpyrrolidinone) (PVP) ASD were evaluated for comparison. Powder X-ray diffraction (XRPD) and differential scanning calorimetry (DSC) were used to examine the crystallinity of ASDs, physical mixtures (PM) and quercetin. ASDs were amorphous up to 50 wt% Que. Que stability against crystallization and solution concentrations from these ASDs were significantly higher than those observed for physical mixtures and crystalline Que. PVP stabilizes against both Que degradation and recrystallization; in contrast, these carboxylated cellulose derivatives inhibit recrystallization but release Que slowly. PVP ASDs afforded fast and complete drug release, while ASDs using these three cellulose derivatives provide slow, incomplete, pH-triggered drug release. PMID:23399255

  9. Essential role of Nrf2 in keratinocyte protection from UVA by quercetin

    SciTech Connect

    Kimura, Shintarou; Warabi, Eiji; Yanagawa, Toru; Ma, Dongmei; Itoh, Ken; Ishii, Yoshiyuki; Kawachi, Yasuhiro; Ishii, Tetsuro

    2009-09-11

    Much of the cell injury caused by ultraviolet A (UVA) irradiation is associated with oxidative stress. Quercetin is a major natural polyphenol that is known to protect cells from UVA-induced damage. Here, we investigated the molecular mechanism of this protection. Quercetin pretreatment strongly suppressed UVA-induced apoptosis in human keratinocyte HaCaT cells, markedly increased protein levels of the transcription factor Nrf2, induced the expression of antioxidative genes, and dramatically reduced the production of reactive oxygen species following UVA irradiation. Importantly, these beneficial effects were greatly attenuated by downregulating Nrf2 expression. Thus, quercetin protects cells from UVA damage mainly by elevating intracellular antioxidative activity via the enhanced accumulation of a transcription factor for antioxidant genes, Nrf2.

  10. Quercetin ameliorates glucose and lipid metabolism and improves antioxidant status in postnatally monosodium glutamate-induced metabolic alterations.

    PubMed

    Seiva, Fábio R F; Chuffa, Luiz Gustavo A; Braga, Camila Pereira; Amorim, João Paulo A; Fernandes, Ana Angélica H

    2012-10-01

    We reported the effects of quercetin on metabolic and hormonal profile as well as serum antioxidant activities in a model of MSG (monosodium glutamate)-induced obesity. Rats were divided into 4 groups: MSG group, submitted to neonatal treatment with high doses of MSG, administrated subcutaneously during 10 days, from 2 day-old; control groups, which received the same volume of saline. After completing 30 day-old, these groups were subdivided into 4 groups: control and MSG groups treated and non-treated with quercetin at doses of 75 mg/kg body weight (i.p.) over 42 days. BW gain and food consumption were higher in MSG treated rats and quercetin significantly reduced BW by 25%. While MSG increased triacylglycerol, total cholesterol and fractions, and reduced HDL concentrations, administration of quercetin normalized HDL-cholesterol and reduced others lipids. Insulin, leptin, glucose and creatinine levels were raised in MSG-treated rats and reduced after quercetin treatment. Alanine transaminase, aspartate transaminase, lactate dehydrogenase and alkaline phosphatase activities were lower after MSG-quercetin combination compared to rats given only MSG. MSG-quercetin combination augmented total protein and urea levels as well as glutathione peroxidase and superoxide dismutase activities in contrast to MSG-treated animals. Quercetin normalized serum lipid and glucose profile and minimized the MSG-related toxic effects, which was associated to its antioxidant properties. PMID:22809473

  11. Investigation of quercetin-induced HepG2 cell apoptosis-associated cellular biophysical alterations by atomic force microscopy.

    PubMed

    Pi, Jiang; Li, Baole; Tu, Lvying; Zhu, Haiyan; Jin, Hua; Yang, Fen; Bai, Haihua; Cai, Huaihong; Cai, Jiye

    2016-03-01

    Quercetin, a wildly distributed bioflavonoid, has been proved to possess excellent antitumor activity on hepatocellular carcinoma (HCC). In the present study, the biophysical properties of HepG2 cells were qualitatively and quantitatively determined using high resolution atomic force microscopy (AFM) to understand the anticancer effects of quercetin on HCC cells at nanoscale. The results showed that quercetin could induce severe apoptosis in HepG2 cells through arrest of cell cycle and disruption of mitochondria membrane potential. Additionally, the nuclei and F-actin structures of HepG2 cells were destroyed by quercetin treatment as well. AFM morphological data showed some typical apoptotic characterization of HepG2 cells with increased particle size and roughness in the ultrastructure of cell surface upon quercetin treatment. As an important biophysical property of cells, the membrane stiffness of HepG2 cells was further quantified by AFM force measurements, which indicated that HepG2 cells became much stiffer after quercetin treatment. These results collectively suggest that quercetin can be served as a potential therapeutic agent for HCC, which not only extends our understanding of the anticancer effects of quercetin against HCC cells into nanoscale, but also highlights the applications of AFM for the investigation of anticancer drugs. SCANNING 38:100-112, 2016. © 2015 Wiley Periodicals, Inc. PMID:26179807

  12. Quercetin treatment ameliorates inflammation and fibrosis in mice with nonalcoholic steatohepatitis.

    PubMed

    Marcolin, Eder; San-Miguel, Beatriz; Vallejo, Daniela; Tieppo, Juliana; Marroni, Norma; González-Gallego, Javier; Tuñón, María J

    2012-10-01

    We investigated whether quercetin protects from steatosis and limits the expression of proinflammatory and fibrogenic genes in C57BL/6J mice with nonalcoholic steatohepatitis (NASH) induced by feeding a methionine-choline-deficient (MCD) diet. Quercetin (50 mg/kg) was given by oral route daily. Mice were randomly divided into 4 groups that received for 2 or 4 wk: the control diet plus vehicle, control diet plus quercetin, MCD diet plus vehicle, and MCD diet plus quercetin. At both 2 and 4 wk, feeding the MCD diet resulted in liver steatosis, inflammatory cell accumulation, oxidative stress evaluated by the concentration of TBARS, and fibrosis evidenced by the staining of α-smooth muscle actin-positive cells in the liver. At both 2 and 4 wk, the MCD diet induced an increase in the mRNA levels of Il6, Tnf, Ptgs2, and Hmgb1 and increased the protein concentrations of Toll-like receptor-4, c-Jun terminal kinase, and p65 NFκB subunit compared with control rats. Feeding the mice the MCD diet also triggered an increase of Col1a1, Col3a1, Plod3, Tgfb1, Smad3, Smad7, Pdgfb, Ctgf, Areg, Mmp9, and Timp1 mRNA levels. These effects were totally or partially prevented by treatment with quercetin. The data obtained suggest that attenuation of multiple profibrotic and proinflammatory gene pathways contributes to the beneficial effects of quercetin in mice with MCD diet-induced steatohepatitis. PMID:22915297

  13. Effect of quercetin against lindane induced alterations in the serum and hepatic tissue lipids in wistar rats

    PubMed Central

    Padma, Viswanadha Vijaya; Lalitha, Gurusamy; Shirony, Nicholson Puthanveedu; Baskaran, Rathinasamy

    2012-01-01

    Objective To assess the effect of quercetin (flavonoid) against lindane induced alterations in lipid profile of wistar rats. Methods Rats were administered orally with lindane (100 mg/kg body weight) and quercetin (10 mg/kg body weight) for 30 days. After the end of treatment period lipid profile was estimated in serum and tissue. Results Elevated levels of serum cholesterol, triglycerides, low density lipoprotein (LDL), very Low Density Lipoprotein (VLDL) and tissue triglycerides, cholesterol with concomitant decrease in serum HDL and tissue phospholipids were decreased in lindane treated rats were found to be significantly decreased in the quercetin and lindane co-treated rats. Conclusions Our study suggests that quercetin has hypolipidemic effect and offers protection against lindane induced toxicity in liver by restoring the altered levels of lipids. The quercetin cotreatment along with lindane for 30 days reversed these biochemical alterations in lipids induced by lindane. PMID:23569870

  14. Response of keloid fibroblasts to Vitamin D3 and quercetin treatment - in vitro study.

    PubMed

    Mathangi Ramakrishnan, K; Babu, M; Lakshmi Madhavi, M S

    2015-09-30

    Keloid scars continue to pose a challenge to clinicians as the treatment armamentarium lacks a formidable agent to tackle them. We have undertaken an in vitro study based on the mechanism of action of Vitamin D3 and quercetin on isolated keloid fibroblasts. Dose-dependent action on the reduction of cellular proliferation, collagen synthesis and induction of apoptosis by Vitamin D3 and quercetin are analyzed and probable mechanism of action is elaborated. This study thus opens up newer avenues in tackling keloid scars effectively. PMID:27279805

  15. Urine recovery experiments with quercetin and other mutagens using the Ames test

    SciTech Connect

    Busch, D.B.; Hatcher, J.F.; Bryan, G.T.

    1986-01-01

    Recovery from urine of the mutagenic activity of 2-anthramine, cyclophosphamide, 7,12-dimethylbenz(a)anthracene, 6-chloro-9-((3-(2-chloroethylamino)-propyl)amino)-2-methoxyacridine dihydrochloride (ICR-191), mitomycin-C, nitrofurantoin, and quercetin was studied with several of the Ames tester strains using acetone-extracted XAD-2 columns with yields ranging from 27% to 79%. Dose responses of the pure chemicals were also studied, and results showed TA 97 to be far more susceptible to quercetin mutagenesis than TA 1537. Reducing pour plate agar volume enhanced mutagenesis.

  16. Response of keloid fibroblasts to Vitamin D3 and quercetin treatment - in vitro study

    PubMed Central

    Mathangi Ramakrishnan, K.; Babu, M.; Lakshmi Madhavi, M.S.

    2015-01-01

    Summary Keloid scars continue to pose a challenge to clinicians as the treatment armamentarium lacks a formidable agent to tackle them. We have undertaken an in vitro study based on the mechanism of action of Vitamin D3 and quercetin on isolated keloid fibroblasts. Dose-dependent action on the reduction of cellular proliferation, collagen synthesis and induction of apoptosis by Vitamin D3 and quercetin are analyzed and probable mechanism of action is elaborated. This study thus opens up newer avenues in tackling keloid scars effectively. PMID:27279805

  17. Chromatographic separation and concentration of quercetin and (+)-catechin using mesoporous composites based on MCM-41

    NASA Astrophysics Data System (ADS)

    Karpov, S. I.; Belanova, N. A.; Korabel'nikova, E. O.; Nedosekina, I. V.; Roessner, F.; Selemenev, V. F.

    2015-05-01

    Data on chromatographic separation of quercetin and (+)-catechin-flavonoids with similar physicochemical (including sorption) properties—are presented. The highest efficiency of chromatographic process at high sorption capacity of the material with respect to quercetin and slightly lower capacity for (+)-catechin were observed when silylated composites of ordered MCM-41 type materials were used. The application of acetonitrile as a solvent increased the sorption capacity of the material and can be recommended for separation of related polyphenol substances and their determination using ordered MCM-41 modified with trimethylchlorosilane as a stationary phase in a chromatographic column.

  18. Synthesis, characterization and investigation of antioxidant activity of cobalt quercetin complex

    NASA Astrophysics Data System (ADS)

    Birjees Bukhari, S.; Memon, Shahabuddin; Mahroof Tahir, M.; Bhanger, M. I.

    2008-12-01

    This article describes a novel synthesis of cobalt and quercetin·2H 2O complex in methanol, characterized by using elemental analysis, UV-visible, 1H NMR, TGA, DSC and IR spectrometric techniques. The formation of complex is deduced from the UV-visible spectra which shows that the successive formation of cobalt-quercetin complex occurs in a ratio of 2:1 (metal/ligand) stoichiometrically. The antioxidant activity of the complex was evaluated by using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging method. In this work, we have shown that the metal complexed flavonoids are much more effective free radical scavengers than the free flavonoids.

  19. Cell specific radiation dosimetry in skeleton from life-span carcinogenesis studies

    SciTech Connect

    Webster, S.S.J.

    1993-04-05

    The osteogenic sarcoma is the dominant life-threatening pathology in lifespan studies of beagles exposed to alpha-emitting bone-seeking radionuclides. It was deduced from these studies that certain skeletal sites are more prone to develop tumors. This project sought to determine the bone cells at risk and their cell-specific radiation dose. The cell-specific radiation dose values are related to loss and high Ra-226 and Pu-239 induced osteogenic sarcoma sites, to test different dose response hypothesis and predict the extent of effects in humans.

  20. Cell specific radiation dosimetry in skeleton from life-span carcinogenesis studies. Final report

    SciTech Connect

    Webster, S.S.J.

    1993-04-05

    The osteogenic sarcoma is the dominant life-threatening pathology in lifespan studies of beagles exposed to alpha-emitting bone-seeking radionuclides. It was deduced from these studies that certain skeletal sites are more prone to develop tumors. This project sought to determine the bone cells at risk and their cell-specific radiation dose. The cell-specific radiation dose values are related to loss and high Ra-226 and Pu-239 induced osteogenic sarcoma sites, to test different dose response hypothesis and predict the extent of effects in humans.

  1. Effect of quercetin on metallothionein, nitric oxide synthases and cyclooxygenase-2 expression on experimental chronic cadmium nephrotoxicity in rats

    SciTech Connect

    Morales, Ana I.; Vicente-Sanchez, Cesar; Jerkic, Mirjana; Santiago, Jose M.; Sanchez-Gonzalez, Penelope D.; Perez-Barriocanal, Fernando; Lopez-Novoa, Jose M. . E-mail: jmlnovoa@usal.es

    2006-01-15

    Inflammation can play a key role in Cd-induced dysfunctions. Quercetin is a potent oxygen free radical scavenger and a metal chelator. Our aim was to study the effect of quercetin on Cd-induced kidney damage and metallothionein expression. The study was performed in Wistar rats that were administered during 9 weeks with either cadmium (1.2 mg Cd/kg/day, s.c.), quercetin (50 mg/kg/day, i.p.) or cadmium + quercetin. Renal toxicity was evaluated by measuring blood urea nitrogen concentration and urinary excretion of enzymes marker of tubular damage. Endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) renal expression were assessed by Western blot. Renal expression of metallothionein 1 and 2 (MT-1, MT-2) and eNOS mRNA was assessed by Northern blot. Our data demonstrated that Cd-induced renal toxicity was markedly reduced in rats that also received quercetin. MT-1 and MT-2 mRNA levels in kidney were substantially increased during treatment with Cd, being even higher when the animals received Cd and quercetin. Renal eNOS expression was significantly higher in rats receiving Cd and quercetin than in animals receiving Cd alone or in control rats. In the group that received Cd, COX-2 and iNOS expression was markedly higher than in control rats. In the group Cd + quercetin, no changes in COX-2 and iNOS expression were observed compared with the control group. Our results demonstrate that quercetin treatment prevents Cd-induced overexpression of iNOS and COX-2, and increases MT expression. These effects can explain the protection by quercetin of Cd-induced nephrotoxicity.

  2. Ameliorative effect of quercetin against arsenic-induced sperm DNA damage and daily sperm production in adult male rats.

    PubMed

    Jahan, Sarwat; Rehman, Saima; Ullah, Hizb; Munawar, Asma; Ain, Qurat Ul; Iqbal, Tariq

    2016-07-01

    In this study, the protective effect of quercetin was evaluated against arsenic induced reproductive ailments in male rats. For this purpose, male rats (n = 5/group) weighing 180-250 g were used. First group served as control, second group received arsenic (50 ppm) in drinking water. Third group was treated with quercetin (50 mg/kg) alone, while fourth group received arsenic + quercetin. All treatments were carried out for 49 days. After treatment, animals were killed by decapitation; testis and epididymis were dissected out. Right epididymis was minced immediately for comet assay, while left epididymis was processed for histology. Similarly, right testis was homogenized for estimation of daily sperm production (DSP) and detection of metal concentration. The results of our research revealed that arsenic treatment did not cause any significant change in body weight and testicular volume. Quercetin treatment significantly prevented tissue deposition of arsenic within the testis. Arsenic treatment caused a significant reduction in DSP, however, in the arsenic + quercetin-treated group and quercetin alone-treated group, DSP was significantly high as compared to the arsenic-treated group. Histological study of epididymis showed empty lumen in arsenic-treated group while in arsenic + quercetin-treated group and quercetin alone-treated group, lumen were filled with sperm and were comparable to control. Sperm DNA damage, induced by arsenic, was significantly reversed toward control levels by supplementation of quercetin. These results suggest that quercetin not only prevents deposition of arsenic in tissues, but can also protect the sperm DNA damage. PMID:26524343

  3. Plasmonic nanobubbles for target cell-specific gene and drug delivery and multifunctional processing of heterogeneous cell systems

    NASA Astrophysics Data System (ADS)

    Lukianova-Hleb, Ekaterina Y.; Huye, Leslie E.; Brenner, Malcolm K.; Lapotko, Dmitri O.

    2014-03-01

    Cell and gene cancer therapies require ex vivo cell processing of human grafts. Such processing requires at least three steps - cell enrichment, cell separation (destruction), and gene transfer - each of which requires the use of a separate technology. While these technologies may be satisfactory for research use, they are of limited usefulness in the clinical treatment setting because they have a low processing rate, as well as a low transfection and separation efficacy and specificity in heterogeneous human grafts. Most problematic, because current technologies are administered in multiple steps - rather than in a single, multifunctional, and simultaneous procedure - they lengthen treatment process and introduce an unnecessary level of complexity, labor, and resources into clinical treatment; all these limitations result in high losses of valuable cells. We report a universal, high-throughput, and multifunctional technology that simultaneously (1) inject free external cargo in target cells, (2) destroys unwanted cells, and (3) preserve valuable non-target cells in heterogeneous grafts. Each of these functions has single target cell specificity in heterogeneous cell system, processing rate > 45 mln cell/min, injection efficacy 90% under 96% viability of the injected cells, target cell destruction efficacy > 99%, viability of not-target cells >99% The developed technology employs novel cellular agents, called plasmonic nanobubbles (PNBs). PNBs are not particles, but transient, intracellular events, a vapor nanobubbles that expand and collapse in mere nanoseconds under optical excitation of gold nanoparticles with short picosecond laser pulses. PNBs of different, cell-specific, size (1) inject free external cargo with small PNBs, (2) Destroy other target cells mechanically with large PNBs and (3) Preserve non-target cells. The multi-functionality, precision, and high throughput of all-in-one PNB technology will tremendously impact cell and gene therapies and other

  4. EXPRESSION OF THE SPERMATOGENIC CELL-SPECIFIC GLYCERALDEHYDE 3-PHOSPHATE DEHYDROGENASE (GAPDS) IN RAT TESTIS

    EPA Science Inventory

    The spermatogenic cell-specific variant of glyceraldehyde 3-phosphate dehydrogenase (GAPDS) has been cloned from a rat testis cDNA library and its pattern of expression determined. A 1417 nucleotide cDNA has been found to encode an enzyme with substantial homology to mouse GAPDS...

  5. Towards an understanding of cell-specific functions of signal-dependent transcription factors.

    PubMed

    Zhang, Dawn X; Glass, Christopher K

    2013-12-01

    The ability to regulate gene expression in a cell-specific manner is a feature of many broadly expressed signal-dependent transcription factors (SDTFs), including nuclear hormone receptors and transcription factors that are activated by cell surface receptors for extracellular signals. As the most plastic cells of the hematopoietic system, macrophages are responsive to a wide spectrum of regulatory molecules and provide a robust model system for investigation of the basis for cell-specific transcriptional responses at a genome-wide level. Here, focusing on recent studies in macrophages, we review the evidence suggesting a model in which cell-specific actions of SDTFs are the consequence of priming functions of lineage determining transcription factors. We also discuss recent findings relating lineage-determining and SDTF activity to alterations in the epigenetic landscape as well as the production and function of enhancer RNAs. These findings have implications for the understanding of how natural genetic variation impacts cell-specific programs of gene expression and suggest new approaches for altering gene expression in vivo. PMID:24130129

  6. Cell-specific intracellular anticancer drug delivery from mesoporous silica nanoparticles with pH sensitivity.

    PubMed

    Luo, Zhong; Cai, Kaiyong; Hu, Yan; Zhang, Beilu; Xu, Dawei

    2012-05-01

    A nanoreservoir for efficient intracellular anticancer drug delivery based on mesoporous silica nanoparticles end-capped with lactobionic acid-grafted bovine serum albumin is fabricated. It demonstrates great potential for both cell-specific endocytosis and intracellular pH-responsive controlled release of drugs. A possible endocytosis pathway/mechanism of the smart controlled drug release system is proposed. PMID:23184747

  7. Fast-dissolving core-shell composite microparticles of quercetin fabricated using a coaxial electrospray process.

    PubMed

    Li, Chen; Yu, Deng-Guang; Williams, Gareth R; Wang, Zhuan-Hua

    2014-01-01

    This study reports on novel fast-dissolving core-shell composite microparticles of quercetin fabricated using coaxial electrospraying. A PVC-coated concentric spinneret was developed to conduct the electrospray process. A series of analyses were undertaken to characterize the resultant particles in terms of their morphology, the physical form of their components, and their functional performance. Scanning and transmission electron microscopies revealed that the microparticles had spherical morphologies with clear core-shell structure visible. Differential scanning calorimetry and X-ray diffraction verified that the quercetin active ingredient in the core and sucralose and sodium dodecyl sulfate (SDS) excipients in the shell existed in the amorphous state. This is believed to be a result of second-order interactions between the components; these could be observed by Fourier transform infrared spectroscopy. In vitro dissolution and permeation studies showed that the microparticles rapidly released the incorporated quercetin within one minute, and had permeation rates across the sublingual mucosa around 10 times faster than raw quercetin. PMID:24643072

  8. Hyperglycemia and anthocyanin inhibit quercetin metabolism in HepG2 cells

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A high glucose (Glu) milieu promotes generation of reactive oxygen species, which may not only cause cellular damage, but also modulate phase II enzymes that are responsible for the metabolism of flavonoids. Thus, we examined the effect of a high Glu milieu on quercetin (Q) metabolism in HepG2 cells...

  9. Rutin, quercetin, and free amino acid analysis in buckwheat (Fagopyrum) seeds from different locations.

    PubMed

    Bai, C Z; Feng, M L; Hao, X L; Zhong, Q M; Tong, L G; Wang, Z H

    2015-01-01

    In this study, five common buckwheats and nine tartary buckwheats grown at different locations were analyzed for the contents of rutin, quercetin, and amino acids by high-performance liquid chromatography and spectrophotometry. The rutin content was higher than quercetin in buckwheat seeds. Rutin content was in the range from 0.05 (0.05 g per 100 g dry seeds) to 1.35% of buckwheat seeds. Quercetin content varied from 0.01 to 0.17% and in some common buckwheats it was even difficult to detect. Comparatively, tartary buckwheat seeds contained more rutin and quercetin than common buckwheat seeds. Meanwhile, the bran has higher rutin content than the farina in tartary buckwheat seeds, with a respective content of 0.45 to 1.19% and 0.14 to 0.67%. It was found that amino acid contents were around 1.79 to 12.65% (farina) and 5.74 to 7.89% (bran) in common buckwheats, and 1.73 to 5.63% (farina) and 2.64 to 16.78% (bran) in tartary buckwheat seeds. The highest total rutin content was found to be 1.35% in tartary buckwheat seeds from Sichuan, China. The highest total amounts of amino acid were detected to be 20.13% in tartary buckwheat seeds from Changzhi, Shanxi Province (China). Our results suggested that food products made of whole-buckwheat flour are healthier than those made of fine white flour. PMID:26782554

  10. Age-related increases in F344 rat intestine microsomal quercetin glucuronidation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to establish the extent age modifies intestinal quercetin glucuronidation capacity. Pooled microsomal fractions of three equidistant small intestine (SI) segments from 4, 12, 18, and 28 mo male F344 rats (n=8/group) were employed to model the enzyme kinetics of UDP-gl...

  11. Quercetin declines plasma exposure of metoprolol tartrate in the rat model

    PubMed Central

    Challa, Siva R.; Challa, Venkatesh R.; Ragam, Satheesh K.

    2014-01-01

    The study was undertaken to evaluate the effect of quercetin on the pharmacokinetics of Metoprolol tartrate. A single dose in vivo pharmacokinetic study was carried out in rat models. In this study, rats were treated with quercetin (10 mg/kg) and metoprolol tartrate (20 mg/kg) orally and blood samples were collected 0, 0.25, 0.5, 0.75, 1, 1.5, 2, 4, 8, 12 h post treatment. Plasma concentration of metoprolol tartrate was estimated using reverse phase-high-performance liquid chromatography method. Area under the plasma concentration-time curve (AUC0-12) of metoprolol has significantly (P < 0.001) decreased by 9.8 times in the metoprolol and quercetin combination group (9434.65 ± 3525.02) when compared with AUC0-12 metoprolol of metoprolol-alone treated group (962.17 ± 242.81). AUC0-∞ of metoprolol has significantly (P < 0.001) decreased by 14.9 times in the combination group (16670.79 ± 12129.06) in comparison to AUC0-∞ of metoprolol of metoprolol-alone treated group (1113.68 ± 441.83). the results obtained herein indicate that quercetin remarkably declines the plasma exposure of metoprolol when concomitantly administered by oral route. PMID:25364697

  12. Quercetin inhibits the migration and proliferation of astrocytes in wound healing.

    PubMed

    Yuan, Zhaohu; Yao, Fang; Hu, Ziyou; Sun, Shumei; Wu, Bingyi

    2015-05-01

    A previous study showed that quercetin inhibits astrogliosis in a scratch-wound model, but did not identify the underlying mechanisms. Here, we show that quercetin exerts no effect on apoptosis or the viability of astrocytes, but significantly inhibits their proliferation, arresting them in the G1 phase and decreasing the percentage of cells in the S and G2 phase. In addition, we found that quercetin significantly decreased the phosphorylation of ERK1/2 and FAK, a downstream ERK signaling protein. Inhibition of this pathway with U0126, an inhibitor of MAP kinase, retarded wound closure, whereas sustained p-ERK1/2 activation, induced by vanadate, restored astrocyte migration. Our findings thus indicate that quercetin inhibits healing in the scratch-wound model of primary astrocytes in two ways: blockade of the G1 to S phase cell cycle transition and inhibition of the ERK/FAK signaling pathway, which may contribute toward decreasing astroglial scar formation in vivo. PMID:25793633

  13. Prevention of N-nitrosodiethylamine-induced lung tumorigenesis by ellagic acid and quercetin in mice.

    PubMed

    Khanduja, K L; Gandhi, R K; Pathania, V; Syal, N

    1999-04-01

    The polyphenolic antioxidants, consumed as an integral part of vegetables, fruits and beverages, are suggested as possessing anticarcinogenic properties. In the present study we have looked into the anticarcinogenic potential of plant polyphenols ellagic acid (EA) and quercetin against N-nitrosodiethylamine-induced lung tumorigenesis in mice. Ellagic acid was able to significantly reduce tumour incidence to 20% from the control value of 72.2%. Similarly, tumour burden was also decreased, although not significantly, from 3.15 to 2.5. Quercetin (QR) caused the tumour incidence to decrease from 76.4% to 44.4% when fed until the third dose of carcinogen. Both of the polyphenols suppressed the tumour incidence mainly by acting at the initiation phase of the carcinogenesis, since continuing the feeding of polyphenols until the termination of the experiment did not cause any apparent change in tumour incidence or tumour burden. Besides this, ellagic acid was found to be a better chemopreventor than quercetin. In order to search for their mechanism of action, the effect of feeding of these compounds on reduced glutathione (GSH), an important endogenous antioxidant, and on lipid peroxidation was investigated. Both ellagic acid and QR caused a significant increase in GSH and decrease in NADPH- and ascorbate-dependent lipid peroxidation. Ellagic acid was found to be more effective in decreasing the lipid peroxidation and increasing the GSH. This may be one of the reasons for its observed better anticarcinogenic property as compared to quercetin. PMID:10418948

  14. Fast Disintegrating Quercetin-Loaded Drug Delivery Systems Fabricated Using Coaxial Electrospinning

    PubMed Central

    Li, Xiao-Yan; Li, Yan-Chun; Yu, Deng-Guang; Liao, Yao-Zu; Wang, Xia

    2013-01-01

    The objective of this study is to develop a structural nanocomposite of multiple components in the form of core-sheath nanofibres using coaxial electrospinning for the fast dissolving of a poorly water-soluble drug quercetin. Under the selected conditions, core-sheath nanofibres with quercetin and sodium dodecyl sulphate (SDS) distributed in the core and sheath part of nanofibres, respectively, were successfully generated, and the drug content in the nanofibres was able to be controlled simply through manipulating the core fluid flow rates. Field emission scanning electron microscope (FESEM) images demonstrated that the nanofibres prepared from the single sheath fluid and double core/sheath fluids (with core-to-sheath flow rate ratios of 0.4 and 0.7) have linear morphology with a uniform structure and smooth surface. The TEM images clearly demonstrated the core-sheath structures of the produced nanocomposites. Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) results verified that quercetin and SDS were well distributed in the polyvinylpyrrolidone (PVP) matrix in an amorphous state, due to the favourite second-order interactions. In vitro dissolution studies showed that the core-sheath composite nanofibre mats could disintegrate rapidly to release quercetin within 1 min. The study reported here provides an example of the systematic design, preparation, characterization and application of a new type of structural nanocomposite as a fast-disintegrating drug delivery system. PMID:24185912

  15. Quercetin as an Antiviral Agent Inhibits Influenza A Virus (IAV) Entry

    PubMed Central

    Wu, Wenjiao; Li, Richan; Li, Xianglian; He, Jian; Jiang, Shibo; Liu, Shuwen; Yang, Jie

    2015-01-01

    Influenza A viruses (IAVs) cause seasonal pandemics and epidemics with high morbidity and mortality, which calls for effective anti-IAV agents. The glycoprotein hemagglutinin of influenza virus plays a crucial role in the initial stage of virus infection, making it a potential target for anti-influenza therapeutics development. Here we found that quercetin inhibited influenza infection with a wide spectrum of strains, including A/Puerto Rico/8/34 (H1N1), A/FM-1/47/1 (H1N1), and A/Aichi/2/68 (H3N2) with half maximal inhibitory concentration (IC50) of 7.756 ± 1.097, 6.225 ± 0.467, and 2.738 ± 1.931 μg/mL, respectively. Mechanism studies identified that quercetin showed interaction with the HA2 subunit. Moreover, quercetin could inhibit the entry of the H5N1 virus using the pseudovirus-based drug screening system. This study indicates that quercetin showing inhibitory activity in the early stage of influenza infection provides a future therapeutic option to develop effective, safe and affordable natural products for the treatment and prophylaxis of IAV infections. PMID:26712783

  16. Myricetin and quercetin attenuate ischemic injury in glial cultures by different mechanisms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have demonstrated that polyphenols from cinnamon and green tea reduce cell swelling and mitochondrial dysfunction in C6 glial cultures following ischemic injury. We tested the protective effects of the flavonoid polyphenols, myricetin and quercetin, on key features of ischemic injury. C6 cultures...

  17. Preparation and characterization of lipid based nanosystems for topical delivery of quercetin.

    PubMed

    Bose, Sonali; Michniak-Kohn, Bozena

    2013-02-14

    The main objective of this study was to evaluate the potential of lipid nanosystems for topical delivery of the naturally occurring flavonoid quercetin. These lipid based nanosystems were manufactured using a solvent free probe ultrasonication process. Formulation factors such as the nature of the lipid (solid/combination of solid and liquid) in solid lipid nanoparticle (SLN) and nanostructured lipid carrier (NLC) systems and drug loading were evaluated to produce an optimum formulation with adequate physical stability for up to 14 weeks at 2-8°C. The mean particle size of the optimized formulation was around 282 nm, with a zeta potential value of -36.57 ± 2.67 mV, indicating the formation of a stable system. Release studies showed a biphasic release profile, characterized by an initial burst release followed by a more controlled release pattern from both SLN and NLC systems. The NLC system showed the highest improvement in topical delivery of quercetin manifested by the amount of quercetin retained in full thickness human skin, compared to a control formulation with similar composition and particle size in the micrometer range. This study demonstrated the feasibility of nanostructured lipid carrier systems for improved topical delivery of quercetin. PMID:23246734

  18. Characterization of citrate capped gold nanoparticle-quercetin complex: Experimental and quantum chemical approach

    NASA Astrophysics Data System (ADS)

    Pal, Rajat; Panigrahi, Swati; Bhattacharyya, Dhananjay; Chakraborti, Abhay Sankar

    2013-08-01

    Quercetin and several other bioflavonoids possess antioxidant property. These biomolecules can reduce the diabetic complications, but metabolize very easily in the body. Nanoparticle-mediated delivery of a flavonoid may further increase its efficacy. Gold nanoparticle is used by different groups as vehicle for drug delivery, as it is least toxic to human body. Prior to search for the enhanced efficacy, the gold nanoparticle-flavonoid complex should be prepared and well characterized. In this article, we report the interaction of gold nanoparticle with quercetin. The interaction is confirmed by different biophysical techniques, such as Scanning Electron Microscope (SEM), Circular Dichroism (CD), Fourier-Transform InfraRed (FT-IR) spectroscopy and Thermal Gravimetric Analysis (TGA) and cross checked by quantum chemical calculations. These studies indicate that gold clusters are covered by citrate groups, which are hydrogen bonded to the quercetin molecules in the complex. We have also provided evidences how capping is important in stabilizing the gold nanoparticle and further enhances its interaction with other molecules, such as drugs. Our finding also suggests that gold nanoparticle-quercetin complex can pass through the membranes of human red blood cells.

  19. Fast-Dissolving Core-Shell Composite Microparticles of Quercetin Fabricated Using a Coaxial Electrospray Process

    PubMed Central

    Li, Chen; Yu, Deng-Guang; Williams, Gareth R.; Wang, Zhuan-Hua

    2014-01-01

    This study reports on novel fast-dissolving core-shell composite microparticles of quercetin fabricated using coaxial electrospraying. A PVC-coated concentric spinneret was developed to conduct the electrospray process. A series of analyses were undertaken to characterize the resultant particles in terms of their morphology, the physical form of their components, and their functional performance. Scanning and transmission electron microscopies revealed that the microparticles had spherical morphologies with clear core-shell structure visible. Differential scanning calorimetry and X-ray diffraction verified that the quercetin active ingredient in the core and sucralose and sodium dodecyl sulfate (SDS) excipients in the shell existed in the amorphous state. This is believed to be a result of second-order interactions between the components; these could be observed by Fourier transform infrared spectroscopy. In vitro dissolution and permeation studies showed that the microparticles rapidly released the incorporated quercetin within one minute, and had permeation rates across the sublingual mucosa around 10 times faster than raw quercetin. PMID:24643072

  20. Improvement in safety and cycle life of lithium-ion batteries by employing quercetin as an electrolyte additive

    NASA Astrophysics Data System (ADS)

    Lee, Meng-Lun; Li, Yu-Han; Yeh, Jien-Wei; Shih, Han C.

    2012-09-01

    Quercetin, an organic antioxidant, has been employed as an additive in lithium-ion cells to enhance the electrochemical performance to enhance the cycle life and the overcharging characteristics of LiPF6/EC + EMC + DMC (1 M) when used as an electrolyte. A LiCoO2/graphite full cell with 0.05% quercetin showed a significant improvement in safety associated with overcharging tolerance and thermal stability, without causing damage in C-rate capability, and even a small improvement in cycle life performance. The quercetin-containing lithium battery showed an improvement in its electrochemical properties with 92% capacity retention after 350 cycles from 2.8 to 4.3 V, at a rate of 1 C; compared to 85% capacity retention for a cell without quercetin operated under the same conditions. The electrochemical impedance spectroscopy (EIS) results for the LiCoO2 cathode show that the addition of 0.05% quercetin provides a significant suppression in the impedance of the cell after 60 cycles. The improvement might result from the formation of a passivation microstructure (from quercetin oxidation) on the electrode's surface. The quercetin-containing batteries provided long term cycling and a high safety performance, making them a viable power source for applications involving electric devices with significant safety requirements.

  1. Quercetin protects human hepatoma HepG2 against oxidative stress induced by tert-butyl hydroperoxide

    SciTech Connect

    Alia, Mario . E-mail: luisgoya@if.csic.es

    2006-04-15

    Flavonols such as quercetin, have been reported to exhibit a wide range of biological activities related to their antioxidant capacity. The objective of the present study was to investigate the protective effect of quercetin on cell viability and redox status of cultured HepG2 cells submitted to oxidative stress induced by tert-butyl hydroperoxide. Concentrations of reduced glutathione and malondialdehyde, generation of reactive oxygen species and activity and gene expression of antioxidant enzymes were used as markers of cellular oxidative status. Pretreatment of HepG2 with 10 {mu}M quercetin completely prevented lactate dehydrogenase leakage from the cells. Pretreatment for 2 or 20 h with all doses of quercetin (0.1-10 {mu}M) prevented the decrease of reduced glutathione and the increase of malondialdehyde evoked by tert-butyl hydroperoxide in HepG2 cells. Reactive oxygen species generation induced by tert-butyl hydroperoxide was significantly reduced when cells were pretreated for 2 or 20 h with 10 {mu}M and for 20 h with 5 {mu}M quercetin. Finally, some of the quercetin treatments prevented the significant increase of glutathione peroxidase, superoxide dismutase, glutathione reductase and catalase activities induced by tert-butyl hydroperoxide. Gene expression of antioxidant enzymes was also affected by the treatment with the polyphenol. The results of the biomarkers analyzed clearly show that treatment of HepG2 cells in culture with the natural dietary antioxidant quercetin strongly protects the cells against an oxidative insult.

  2. Effectiveness of Periodic Treatment of Quercetin against Influenza A Virus H1N1 through Modulation of Protein Expression.

    PubMed

    Vaidya, Bipin; Cho, Se-Young; Oh, Kyung-Seo; Kim, Song Hak; Kim, Yeong O; Jeong, Eun-Hye; Nguyen, Thoa Thi; Kim, Sung Hyun; Kim, In Seon; Kwon, Joseph; Kim, Duwoon

    2016-06-01

    Kimchi, a traditional fermented food regularly consumed in Korea, contains various types of antimicrobial compounds. Among the tested compounds present in common spices used in Kimchi, quercetin showed the highest selectivity index against influenza A virus (IAV) H1N1. In this study, the effect of pretreatment and periodic treatment with quercetin against IAV in Madin-Darby canine kidney cells was observed. Compared to pretreatment, periodic treatment resulted in significantly higher cell viability but lower relative expression of the IAV PA gene and total apoptosis and cell death. To explain the mechanisms underlying the antiviral effects of quercetin treatment, a comparative proteomic analysis was performed in four samples (mock, quercetin-treated, IAV-infected, and quercetin-treated IAV-infected). Among the 220 proteins, 56 proteins were classified nonhierarchically into three clusters and were differentially modulated by quercetin treatment in IAV-infected cells. Post-translational modifications were identified in 68 proteins. In conclusion, periodic treatment with quercetin is effective in reducing IAV infection, and differentially regulates the expression of key proteins, including heat shock proteins, fibronectin 1, and prohibitin to reduce IAV replication. PMID:27157719

  3. Modulation of paraoxonase 2 (PON2) in mouse brain by the polyphenol quercetin: a mechanism of neuroprotection?

    PubMed Central

    Costa, Lucio G.; Tait, Leah; de Laat, Rian; Dao, Khoi; Giordano, Gennaro; Pellacani, Claudia; Cole, Toby B.; Furlong, Clement E.

    2013-01-01

    Quercetin is a common flavonoid polyphenol which has been shown to exert neuroprotective actions in vitro and in vivo. Though quercetin has antioxidant properties, it has been suggested that neuroprotection may be ascribed to its ability of inducing the cell’s own defense mechanisms. The present study investigated whether quercetin could increase the levels of paraoxonase 2 (PON2), a mitochondrial enzyme expressed in brain cells, which has been shown to have potent antioxidant properties. PON2 protein, mRNA, and lactonase activity were highest in mouse striatal astrocytes. Quercetin increased PON2 levels, possibly by activating the JNK/AP-1 pathway. The increased PON2 levels induced by quercetin resulted in decreased oxidative stress and ensuing toxicity induced by two oxidants. The neuroprotective effect of quercetin was significantly diminished in cells from PON2 knockout mice. These findings suggest that induction of PON2 by quercetin represents an important mechanism by which this polyphenol may exert its neuroprotective action. PMID:23743621

  4. Quercetin Inhibits Fibroblast Activation and Kidney Fibrosis Involving the Suppression of Mammalian Target of Rapamycin and β-catenin Signaling

    PubMed Central

    Ren, Jiafa; Li, Jianzhong; Liu, Xin; Feng, Ye; Gui, Yuan; Yang, Junwei; He, Weichun; Dai, Chunsun

    2016-01-01

    Quercetin, a flavonoid found in a wide variety of plants and presented in human diet, displays promising potential in preventing kidney fibroblast activation. However, whether quercetin can ameliorate kidney fibrosis in mice with obstructive nephropathy and the underlying mechanisms remain to be further elucidated. In this study, we found that administration of quercetin could largely ameliorate kidney interstitial fibrosis and macrophage accumulation in the kidneys with obstructive nephropathy. MTORC1, mTORC2, β-catenin as well as Smad signaling were activated in the obstructive kidneys, whereas quercetin could markedly reduce their abundance except Smad3 phosphorylation. In cultured NRK-49F cells, quercetin could inhibit α-SMA and fibronectin (FN) expression induced by TGFβ1 treatment. MTORC1, mTORC2, β-catenin and Smad signaling pathways were stimulated by TGFβ1 at a time dependent manner. Similar to those findings in the obstructive kidneys, mTORC1, mTORC2 and β-catenin, but not Smad signaling pathways were remarkably blocked by quercetin treatment. Together, these results suggest that quercetin inhibits fibroblast activation and kidney fibrosis involving a combined inhibition of mTOR and β-catenin signaling transduction, which may act as a therapeutic candidate for patients with chronic kidney diseases. PMID:27052477

  5. Therapeutic detoxification of quercetin against carbon tetrachloride-induced acute liver injury in mice and its mechanism*

    PubMed Central

    Zhang, Jia-qi; Shi, Liang; Xu, Xi-ning; Huang, Si-chong; Lu, Bin; Ji, Li-li; Wang, Zheng-tao

    2014-01-01

    This study observes the therapeutic detoxification of quercetin, a well-known flavonoid, against carbon tetrachloride (CCl4) induced acute liver injury in vivo and explores its mechanism. Quercetin decreased CCl4-increased serum activities of alanine and aspartate aminotransferases (ALT/AST) when orally taken 30 min after CCl4 intoxication. The results of a histological evaluation further evidenced the ability of quercetin to protect against CCl4-induced liver injury. Quercetin decreased the CCl4-increased malondialdehyde (MDA) and reduced the glutathione (GSH) amounts in the liver. It also reduced the enhanced immunohistochemical staining of the 4-hydroxynonenal (4-HNE) in the liver induced by CCl4. Peroxiredoxin (Prx) 1, 2, 3, 5, 6, thioredoxin reductase 1 and 2 (TrxR1/2), thioredoxin 1 and 2 (Trx1/2), nuclear factor erythroid 2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1) all play critical roles in maintaining cellular redox homeostasis. Real-time polymerase chain reaction (PCR) results demonstrated that quercetin reversed the decreased mRNA expression of all those genes induced by CCl4. In conclusion, our results demonstrate that quercetin ameliorates CCl4-induced acute liver injury in vivo via alleviating oxidative stress injuries when orally taken after CCl4 intoxication. This protection may be caused by the elevation of the antioxidant capacity induced by quercetin. PMID:25471833

  6. Possible use of quercetin, an antioxidant, for protection of cells suffering from overload of intracellular Ca2+: a model experiment.

    PubMed

    Sakanashi, Yoko; Oyama, Keisuke; Matsui, Hiroko; Oyama, Toshihisa B; Oyama, Tomohiro M; Nishimura, Yumiko; Sakai, Hitomi; Oyama, Yasuo

    2008-08-01

    Quercetin is known to protect the cells suffering from oxidative stress. The oxidative stress elevates intracellular Ca(2+) concentration, one of the phenomena responsible for cell death. Therefore, we hypothesized that quercetin would protect the cells suffering from overload of intracellular Ca(2+). To test the hypothesis, the effects of quercetin on the cells suffering from oxidative stress and intracellular Ca(2+) overload were examined by using a flow cytometer with appropriate fluorescence probes (propidium iodide, fluo-3-AM, and annexin V-FITC) and rat thymocytes. The concentrations (1-30 microM) of quercetin to protect the cells suffering from intracellular Ca(2+) overload by A23187, a calcium ionophore, were similar to those for the cells suffering from oxidative stress by H(2)O(2). The cell death respectively induced by H(2)O(2) and A23187 was significantly suppressed by removal of external Ca(2+). Furthermore, quercetin greatly delayed the process of Ca(2+)-dependent cell death although it did not significantly affect the elevation of intracellular Ca(2+) concentration by H(2)O(2) and A23187, respectively. It is concluded that quercetin can protect the cells from oxidative injury in spite of increased concentration of intracellular Ca(2+). Results suggest that quercetin is also used for protection of cells suffering from overload of intracellular Ca(2+). PMID:18586279

  7. Cancer

    MedlinePlus

    ... your life Being exposed to chemicals that can cause cancer Being at risk for skin cancer Depending on ... than nonsmokers. Other forms of tobacco can also cause cancer, such as cigars, chewing tobacco and snuff. If ...

  8. Effects of quercetin on the sleep-wake cycle in rats: involvement of gamma-aminobutyric acid receptor type A in regulation of rapid eye movement sleep.

    PubMed

    Kambe, Daiji; Kotani, Makiko; Yoshimoto, Makoto; Kaku, Shinsuke; Chaki, Shigeyuki; Honda, Kazuki

    2010-05-12

    The bioflavonoid quercetin is widely found in plants and exerts a large number of biological activities such as anti-hypertensive and anti-inflammatory properties. However, the effect of quercetin on the sleep-wake cycle has not been investigated. In the present study, we investigated the effect of quercetin on sleep-wake regulation. Intraperitoneal administration of quercetin (200mg/kg) significantly increased non-rapid eye movement (non-REM) sleep during dark period in rats, while it significantly decreased REM sleep. The decrease in REM sleep induced by quercetin was blocked by intracerebroventricular (i.c.v.) injection of bicuculline, a GABA(A) receptor antagonist. In contrast, the increase in non-REM sleep induced by quercetin was not affected by i.c.v. injection of bicuculline. Therefore, the present results suggest that quercetin alters the sleep-wake cycle partly through activation of GABA(A) receptors. PMID:20303338

  9. Silica/quercetin sol-gel hybrids as antioxidant dental implant materials

    NASA Astrophysics Data System (ADS)

    Catauro, Michelina; Papale, Ferdinando; Bollino, Flavia; Piccolella, Simona; Marciano, Sabina; Nocera, Paola; Pacifico, Severina

    2015-06-01

    The development of biomaterials with intrinsic antioxidant properties could represent a valuable strategy for preventing the onset of peri-implant diseases. In this context, quercetin, a naturally occurring flavonoid, has been entrapped at different weight percentages in a silica-based inorganic material by a sol-gel route. The establishment of hydrogen bond interactions between the flavonol and the solid matrix was ascertained by Fourier transform infrared spectroscopy. This technique also evidenced changes in the stretching frequencies of the quercetin dienonic moiety, suggesting that the formation of a secondary product occurs. Scanning electron microscopy was applied to detect the morphology of the synthesized materials. Their bioactivity was shown by the formation of a hydroxyapatite layer on sample surface soaked in a fluid that simulates the composition of human blood plasma. When the potential release of flavonol was determined by liquid chromatography coupled with ultraviolet and electrospray ionization tandem mass spectrometry techniques, the eluates displayed a retention time that was 0.5 min less than quercetin. Collision-activated dissociation mass spectrometry and untraviolet-visible spectroscopy were in accordance with the release of a quercetin derivative. The antiradical properties of the investigated systems were evaluated by DPPH and ABTS methods, whereas the 2,7-dichlorofluorescein diacetate assay highlighted their ability to inhibit the H2O2-induced intracellular production of reactive oxygen species in NIH-3T3 mouse fibroblast cells. Data obtained, along with data gathered from the MTT cytotoxicity test, revealed that the materials that entrapped the highest amount of quercetin showed notable antioxidant effectiveness.

  10. The protective effects of oral low-dose quercetin on diabetic nephropathy in hypercholesterolemic mice

    PubMed Central

    Gomes, Isabele B. S.; Porto, Marcella L.; Santos, Maria C. L. F. S.; Campagnaro, Bianca P.; Gava, Agata L.; Meyrelles, Silvana S.; Pereira, Thiago M. C.; Vasquez, Elisardo C.

    2015-01-01

    Aims: Diabetic nephropathy (DN) is one of the most important causes of chronic renal disease, and the incidence of DN is increasing worldwide. Considering our previous report (Gomes et al., 2014) indicating that chronic treatment with oral low-dose quercetin (10 mg/Kg) demonstrated anti-oxidative, anti-apoptotic and renoprotective effects in the C57BL/6J model of DN, we investigated whether this flavonoid could also have beneficial effects in concurrent DN and spontaneous atherosclerosis using the apolipoprotein E-deficient mouse (apoE−/−). Methods: Streptozotocin was used to induce diabetes (100 mg/kg/day, 3 days) in male apoE−/− mice (8 week-old). After 6 weeks, the mice were randomly separated into DQ: diabetic apoE−/− mice treated with quercetin (10 mg/kg/day, 4 weeks, n = 8), DV: diabetic ApoE−/− mice treated with vehicle (n = 8) and ND: non-treated non-diabetic mice (n = 8). Results: Quercetin treatment diminished polyuria (~30%; p < 0.05), glycemia (~25%, p < 0.05), normalized the hypertriglyceridemia. Moreover, this bioflavonoid diminished creatininemia (~30%, p < 0.01) and reduced proteinuria but not to normal levels. We also observed protective effects on the renal structural changes, including normalization of the index of glomerulosclerosis and kidney weight/body weight. Conclusions: Our data revealed that quercetin treatment significantly reduced DN in hypercholesterolemic mice by inducing biochemical changes (decrease in glucose and triglycerides serum levels) and reduction of glomerulosclerosis. Thus, this study highlights the relevance of quercetin as an alternative therapeutic option for DN, including in diabetes associated with dyslipidemia. PMID:26388784

  11. Protective effect of quercetin on cadmium-induced oxidative toxicity on germ cells in male mice.

    PubMed

    Bu, Tongliang; Mi, Yuling; Zeng, Weidong; Zhang, Caiqiao

    2011-03-01

    Cadmium is a toxic heavy metal that is widely distributed in the environment. As a critical process, oxidative toxicity mediates the morphological and functional damages in germ cells after cadmium exposure. In this study, the protective effect of quercetin on cadmium-induced oxidative toxicity was investigated in mouse testicular germ cells. After oral administration of cadmium chloride at 4 mg/kg body weight for 2 weeks, damages in spermatozoa occurred in the early stage of spermatogenesis. Cadmium treatment significantly decreased the testicular antioxidant system, including decreases in the glutathione (GSH) level, superoxide dismutase (SOD), and GSH peroxidase (GSH-Px) activities. Moreover, exposure to cadmium resulted in an increase of hydrogen peroxide production and lipid peroxidation in testes. In addition, cadmium provoked germ cell apoptosis by upregulating expression of the proapoptotic proteins Bax and caspase-3 and downregulating expression of the antiapoptotic protein Bcl-XL. However, combined administration of a common flavonoid quercetin at 75 mg/kg body weight significantly attenuated cadmium-induced germ cell apoptosis by suppressing the hydrogen peroxide production and lipid peroxidation in testicular tissue. Simultaneous supplementation of quercetin markedly restored the decrease in GSH level and SOD and GSH-Px activities elicited by cadmium treatment. Additionally, quercetin protected germ cells from cadmium-induced apoptosis by downregulating the expression of Bax and caspase-3 and upregulating Bcl-XL expression. These results indicate that quercetin, due to its antioxidative and antiapoptotic characters, may manifest effective protective action against cadmium-induced oxidative toxicity in mouse testicular germ cells. PMID:21337715

  12. In Vitro Antiophidian Mechanisms of Hypericum brasiliense Choisy Standardized Extract: Quercetin-Dependent Neuroprotection

    PubMed Central

    Lucho, Ana Paula de Bairros; Vinadé, Lúcia; Seibert França, Hildegardo; Marangoni, Sérgio; Rodrigues-Simioni, Léa

    2013-01-01

    The neuroprotection induced by Hypericum brasiliense Choisy extract (HBE) and its main active polyphenol compound quercetin, against Crotalus durissus terrificus (Cdt) venom and crotoxin and crotamine, was enquired at both central and peripheral mammal nervous system. Cdt venom (10 μg/mL) or crotoxin (1 μg/mL) incubated at mouse phrenic nerve-diaphragm preparation (PND) induced an irreversible and complete neuromuscular blockade, respectively. Crotamine (1 μg/mL) only induced an increase of muscle strength at PND preparations. At mouse brain slices, Cdt venom (1, 5, and 10 μg/mL) decreased cell viability. HBE (100 μg/mL) inhibited significantly the facilitatory action of crotamine (1 μg/mL) and was partially active against the neuromuscular blockade of crotoxin (1 μg/mL) (data not shown). Quercetin (10 μg/mL) mimicked the neuromuscular protection of HBE (100 μg/mL), by inhibiting almost completely the neurotoxic effect induced by crotoxin (1 μg/mL) and crotamine (1 μg/mL). HBE (100 μg/mL) and quercetin (10 μg/mL) also increased cell viability in mice brain slices. Quercetin (10 μg/mL) was more effective than HBE (100 μg/mL) in counteracting the cell lysis induced by Cdt venom (1 and 10 μg/mL, resp.). These results and a further phytochemical and toxicological investigations could open new perspectives towards therapeutic use of Hypericum brasiliense standardized extract and quercetin, especially to counteract the neurotoxic effect induced by snake neurotoxic venoms. PMID:24490174

  13. Effects of low doses of quercetin and genistein on oxidation and carbonylation in hemoglobin and myoglobin.

    PubMed

    Boadi, William Y; Johnson, Damitea

    2014-09-01

    Protein-bound carbonyls have been shown to increase with age as well as in numerous diseases including rheumatoid arthritis, adult respiratory syndrome pulmonary fibrosis, diabetes, Parkinson's disease, and Alzheimer's just to mention a few. The effects of the flavonoids quercetin and genistein were investigated according to their ability to inhibit the oxidation of hemoglobin and myoglobin via the Fenton's pathway. Antioxidative activity of the flavonoids were determined by oxidizing hemoglobin and myoglobin in separate experiments with 50 μM Fe(2+) and 0.01 mM hydrogen peroxide (H2O2) with and without quercetin and/or genistein. The samples were treated singly with either quercetin, genistein, or in combination at concentrations of 1.0, 1.5, 2.0, 2.5, 3.0, and 3.5 μM, respectively, dissolved in dimethyl sulfoxide (DMSO). Samples were then incubated in a water bath at 37°C for 8, 12, and 24 hr, respectively. Levels of carbonylation were assayed by the protein carbonyl assay and the carbonyl levels quantified and expressed per mg of protein. The results indicate that protein carbonyls for samples treated with quercetin or genistein decreased in a dose-dependent manner compared to the controls. That of quercetin compared to genistein was more efficient in reducing the levels of protein carbonylation in hemoglobin and myoglobin, respectively. The combination of both flavonoids did show a gradual decrease in carbonyl compounds for only hemoglobin for all the doses and times tested. The results indicate that both flavonoids at low doses inhibited carbonylation in both hemoglobin and myoglobin and the inhibition may be attributed to the prevention of protein oxidation. PMID:25026201

  14. Biodegradable polymeric micelle-encapsulated quercetin suppresses tumor growth and metastasis in both transgenic zebrafish and mouse models

    NASA Astrophysics Data System (ADS)

    Wu, Qinjie; Deng, Senyi; Li, Ling; Sun, Lu; Yang, Xi; Liu, Xinyu; Liu, Lei; Qian, Zhiyong; Wei, Yuquan; Gong, Changyang

    2013-11-01

    Quercetin (Que) loaded polymeric micelles were prepared to obtain an aqueous formulation of Que with enhanced anti-tumor and anti-metastasis activities. A simple solid dispersion method was used, and the obtained Que micelles had a small particle size (about 31 nm), high drug loading, and high encapsulation efficiency. Que micelles showed improved cellular uptake, an enhanced apoptosis induction effect, and stronger inhibitory effects on proliferation, migration, and invasion of 4T1 cells than free Que. The enhanced in vitro antiangiogenesis effects of Que micelles were proved by the results that Que micelles significantly suppressed proliferation, migration, invasion, and tube formation of human umbilical vein endothelial cells (HUVECs). Subsequently, transgenic zebrafish models were employed to investigate anti-tumor and anti-metastasis effects of Que micelles, in which stronger inhibitory effects of Que micelles were observed on embryonic angiogenesis, tumor-induced angiogenesis, tumor growth, and tumor metastasis. Furthermore, in a subcutaneous 4T1 tumor model, Que micelles were more effective in suppressing tumor growth and spontaneous pulmonary metastasis, and prolonging the survival of tumor-bearing mice. Besides, immunohistochemical and immunofluorescent assays suggested that tumors in the Que micelle-treated group showed more apoptosis, fewer microvessels, and fewer proliferation-positive cells. In conclusion, Que micelles, which are synthesized as an aqueous formulation of Que, possess enhanced anti-tumor and anti-metastasis activity, which can serve as potential candidates for cancer therapy.

  15. Germ cell-specific expression of Cre recombinase using the VASA promoter in the pig.

    PubMed

    Song, Yuning; Lai, Liangxue; Li, Li; Huang, Yongye; Wang, Anfeng; Tang, Xiaochun; Pang, Daxin; Li, Zhanjun; Ouyang, Hongsheng

    2016-01-01

    The Cre-loxP system is a powerful tool for genetic analysis of distinct cell lineages and tissue-specific gene knockout in animal models. VASA is specifically expressed in reproductive tissues, and is known to play important roles in spermatogenesis and germ-cell growth. In this study, Cre recombinase transgenic pigs under the control of the VASA promoter were generated by somatic cell nuclear transfer. Germ cell-specific expression of Cre recombinase in VASA-Cre transgenic pigs was shown by western blotting and immunohistochemistry. VASA-Cre transgenic pigs will be a useful tool for germ cell-specific gene knockout and a disease model for disorders of the reproductive system. PMID:27047735

  16. Murine somatic cell nuclear transfer using reprogrammed donor cells expressing male germ cell-specific genes.

    PubMed

    Kang, Hoin; Park, Jong Im; Roh, Sangho

    2016-01-01

    In vivo-matured mouse oocytes were enucleated, and a single murine embryonic fibroblast (control or reprogrammed by introducing extracts from murine testis tissue, which showed expression of male germ cell-specific genes) was injected into the cytoplasm of the oocytes. The rate of blastocyst development and expression levels of Oct-4, Eomes and Cdx-2 were not significantly different in both experimental groups. However, the expression levels of Nanog, Sox9 and Glut-1 were significantly increased when reprogrammed cells were used as donor nuclei. Increased expression of Nanog can be supportive of complete reprogramming of somatic cell nuclear transfer murine embryos. The present study suggested that donor cells expressing male germ cell-specific genes can be reconstructed and can develop into embryos with normal high expression of developmentally essential genes. PMID:26369430

  17. Cell-Specific Multifunctional Processing of Heterogeneous Cell Systems in a Single Laser Pulse Treatment

    PubMed Central

    Lukianova-Hleb, Ekaterina Y.; Mutonga, Martin B. G.; Lapotko, Dmitri O.

    2012-01-01

    Current methods of cell processing for gene and cell therapies use several separate procedures for gene transfer and cell separation or elimination, because no current technology can offer simultaneous multi-functional processing of specific cell sub-sets in highly heterogeneous cell systems. Using the cell-specific generation of plasmonic nanobubbles of different sizes around cell-targeted gold nanoshells and nanospheres, we achieved simultaneous multifunctional cell-specific processing in a rapid single 70 ps laser pulse bulk treatment of heterogeneous cell suspension. This method supported the detection of cells, delivery of external molecular cargo to one type of cells and the concomitant destruction of another type of cells without damaging other cells in suspension, and real-time guidance of the two above cellular effects. PMID:23167546

  18. Elevated Cell-Specific Microparticles Are a Biological Marker for Cerebral Dysfunctions in Human Severe Malaria

    PubMed Central

    Pankoui Mfonkeu, Joël Bertrand; Gouado, Inocent; Fotso Kuaté, Honoré; Zambou, Odile; Amvam Zollo, Paul Henri; Grau, Georges Emile Raymond; Combes, Valéry

    2010-01-01

    Cerebral malaria (CM) and severe anemia (SA) are the most severe complications of Plasmodium falciparum infections. Although increased release of endothelial microparticles (MP) correlates with malaria severity, the full extent of vascular cell vesiculation remains unknown. Here, we characterize the pattern of cell-specific MP in patients with severe malaria. We tested the hypothesis that systemic vascular activation contributes to CM by examining origins and levels of plasma MP in relation to clinical syndromes, disease severity and outcome. Patients recruited in Douala, Cameroon, were assigned to clinical groups following WHO criteria. MP quantitation and phenotyping were carried out using cell-specific markers by flow cytometry using antibodies recognizing cell-specific surface markers. Platelet, erythrocytic, endothelial and leukocytic MP levels were elevated in patients with cerebral dysfunctions and returned to normal by discharge. In CM patients, platelet MP were the most abundant and their levels significantly correlated with coma depth and thrombocytopenia. This study shows for the first time a widespread enhancement of vesiculation in the vascular compartment appears to be a feature of CM but not of SA. Our data underpin the role of MP as a biomarker of neurological involvement in severe malaria. Therefore, intervention to block MP production in severe malaria may provide a new therapeutic pathway. PMID:20976232

  19. Highly specific and potently activating Vγ9Vδ2-T cell specific nanobodies for diagnostic and therapeutic applications.

    PubMed

    de Bruin, Renée C G; Lougheed, Sinéad M; van der Kruk, Liza; Stam, Anita G; Hooijberg, Erik; Roovers, Rob C; van Bergen En Henegouwen, Paul M P; Verheul, Henk M W; de Gruijl, Tanja D; van der Vliet, Hans J

    2016-08-01

    Vγ9Vδ2-T cells constitute the predominant subset of γδ-T cells in human peripheral blood and have been shown to play an important role in antimicrobial and antitumor immune responses. Several efforts have been initiated to exploit these cells for cancer immunotherapy, e.g. by using phosphoantigens, adoptive cell transfer, and by a bispecific monoclonal antibody based approach. Here, we report the generation of a novel set of Vγ9Vδ2-T cell specific VHH (or nanobody). VHH have several advantages compared to conventional antibodies related to their small size, stability, ease of generating multispecific molecules and low immunogenicity. With high specificity and affinity, the anti-Vγ9Vδ2-T cell receptor VHHs are shown to be useful for FACS, MACS and immunocytochemistry. In addition, some VHH were found to specifically activate Vγ9Vδ2-T cells. Besides being of possible immunotherapeutic value, these single domain antibodies will be of great value in the further study of this important immune effector cell subset. PMID:27373969

  20. Large, Male Germ Cell-Specific Hypomethylated DNA Domains With Unique Genomic and Epigenomic Features on the Mouse X Chromosome

    PubMed Central

    Ikeda, Rieko; Shiura, Hirosuke; Numata, Koji; Sugimoto, Michihiko; Kondo, Masayo; Mise, Nathan; Suzuki, Masako; Greally, John M.; Abe, Kuniya

    2013-01-01

    To understand the epigenetic regulation required for germ cell-specific gene expression in the mouse, we analysed DNA methylation profiles of developing germ cells using a microarray-based assay adapted for a small number of cells. The analysis revealed differentially methylated sites between cell types tested. Here, we focused on a group of genomic sequences hypomethylated specifically in germline cells as candidate regions involved in the epigenetic regulation of germline gene expression. These hypomethylated sequences tend to be clustered, forming large (10 kb to ∼9 Mb) genomic domains, particularly on the X chromosome of male germ cells. Most of these regions, designated here as large hypomethylated domains (LoDs), correspond to segmentally duplicated regions that contain gene families showing germ cell- or testis-specific expression, including cancer testis antigen genes. We found an inverse correlation between DNA methylation level and expression of genes in these domains. Most LoDs appear to be enriched with H3 lysine 9 dimethylation, usually regarded as a repressive histone modification, although some LoD genes can be expressed in male germ cells. It thus appears that such a unique epigenomic state associated with the LoDs may constitute a basis for the specific expression of genes contained in these genomic domains. PMID:23861320

  1. N-Butyl-4-butyl­imino-2-methyl­pentan-2-aminium (E)-quercetinate

    PubMed Central

    Grosu, Ioana-Georgeta; Borodi, Gheorghe; Pop, Mihaela Maria

    2012-01-01

    The title salt, C14H31N2 +·C15H9O7 −, was obtained in the reaction of quercetin with n-butyl­amine in a mixture of acetone and hexane. The crystal structure determination shows that the quercetin donates one of its phenol H atoms to the N-butyl-4-butyl­imino-2-methyl­pentan-2-amine mol­ecule. The crystal structure of the salt is stabilized by intramolecular (N—H⋯N for the cation and O—H⋯O for the anion) and intermolecular hydrogen bonding (N—H⋯O between cation–anion pairs and O—H⋯O between anions). Quercetin molecules form dimers connected into a two-dimensional network. The dihedral angle between the quercetin ring systems is 19.61 (8)°. PMID:22904895

  2. In silico analysis and molecular docking studies of potential angiotensin-converting enzyme inhibitor using quercetin glycosides

    PubMed Central

    Muhammad, Syed Aun; Fatima, Nighat

    2015-01-01

    The purpose of this study was to analyze the inhibitory action of quercetin glycosides by computational docking studies. For this, natural metabolite quercetin glycosides isolated from buckwheat and onions were used as ligand for molecular interaction. The crystallographic structure of molecular target angiotensin-converting enzyme (ACE) (peptidyl-dipeptidase A) was obtained from PDB database (PDB ID: 1O86). Enalapril, a well-known brand of ACE inhibitor was taken as the standard for comparative analysis. Computational docking analysis was performed using PyRx, AutoDock Vina option based on scoring functions. The quercetin showed optimum binding affinity with a molecular target (angiotensin-converting-enzyme) with the binding energy of −8.5 kcal/mol as compared to the standard (−7.0 kcal/mol). These results indicated that quercetin glycosides could be one of the potential ligands to treat hypertension, myocardial infarction, and congestive heart failure. PMID:26109757

  3. Detection of Tumor Cell-Specific mRNA and Protein in Exosome-Like Microvesicles from Blood and Saliva

    PubMed Central

    Yang, Jieping; Wei, Fang; Schafer, Christopher; Wong, David T. W.

    2014-01-01

    The discovery of disease-specific biomarkers in oral fluids has revealed a new dimension in molecular diagnostics. Recent studies have reported the mechanistic involvement of tumor cells derived mediators, such as exosomes, in the development of saliva-based mRNA biomarkers. To further our understanding of the origins of disease-induced salivary biomarkers, we here evaluated the hypothesis that tumor-shed secretory lipidic vesicles called exosome-like microvesicles (ELMs) that serve as protective carriers of tissue-specific information, mRNAs, and proteins, throughout the vasculature and bodily fluids. RNA content was analyzed in cell free-saliva and ELM-enriched fractions of saliva. Our data confirmed that the majority of extracellular RNAs (exRNAs) in saliva were encapsulated within ELMs. Nude mice implanted with human lung cancer H460 cells expressing hCD63-GFP were used to follow the circulation of tumor cell specific protein and mRNA in the form of ELMs in vivo. We were able to identify human GAPDH mRNA in ELMs of blood and saliva of tumor bearing mice using nested RT-qPCR. ELMs positive for hCD63-GFP were detected in the saliva and blood of tumor bearing mice as well as using electric field-induced release and measurement (EFIRM). Altogether, our results demonstrate that ELMs carry tumor cell–specific mRNA and protein from blood to saliva in a xenografted mouse model of human lung cancer. These results therefore strengthen the link between distal tumor progression and the biomarker discovery of saliva through the ELMs. PMID:25397880

  4. Quercetin-imprinted chromatographic sorbents revisited: optimization of synthesis and rebinding protocols for application to natural resources.

    PubMed

    Pardo, Antonelle; Mespouille, Laetitia; Blankert, Bertrand; Trouillas, Patrick; Surin, Mathieu; Dubois, Philippe; Duez, Pierre

    2014-10-17

    Molecularly imprinted polymers (MIPs) based on quercetin and synthesized by either bulk, precipitation or suspension polymerization were characterized in terms of size and shape by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). After a study of rebinding protocols, the optimal materials were evaluated as sorbents for solid-phase extraction (SPE) and high-performance liquid chromatography (HPLC) to confirm the presence of imprinted cavities and to assess their selectivity. Besides quercetin, other structurally related natural compounds, naringenin, daidzein and curcumin, were employed for selectivity tests of MIPs. Although rebinding protocols previously described for such MIPs are typically based on binding, washing and eluting methanol-based solutions, we show that this highly polar solvent leads to weak specific interactions (imprinting factor<1) and poor sorbent properties, most probably because of hydrogen-bonding interferences between the MIP and MeOH. Similar experiments performed in tetrahydrofuran yield to much more improved properties (imprinting factor>2.4). This calls for reviewing most of previously published data on quercetin-MIPs; in proper binding conditions, published MIPs may prove more performing than initially assessed. As expected, tested MIPs exhibited the highest selective rebinding towards quercetin template (imprinting effect, quercetin, 3.41; naringenin, 1.54; daidzein, 1.38; curcumin, 1.67); the differences in selectivity between quercetin analogues were explained by the ligand geometries and H-bonding patterns obtained from quantum-chemical calculations. The evaluation of MIPs under identical analytical conditions allowed investigating the effect of the production method on chromatographic performances. The MIPs in bead materials (for quercetin, peak width, 0.69; number of theoretical plates, 143; symmetry factor, 2.22) provided a significant improvement in chromatographic efficiency over the bulk materials

  5. Cell-Specific Promoters Enable Lipid-Based Nanoparticles to Deliver Genes to Specific Cells of the Retina In Vivo

    PubMed Central

    Wang, Yuhong; Rajala, Ammaji; Cao, Binrui; Ranjo-Bishop, Michelle; Agbaga, Martin-Paul; Mao, Chuanbin; Rajala, Raju V.S.

    2016-01-01

    Non-viral vectors, such as lipid-based nanoparticles (liposome-protamine-DNA complex [LPD]), could be used to deliver a functional gene to the retina to correct visual function and treat blindness. However, one of the limitations of LPD is the lack of cell specificity, as the retina is composed of seven types of cells. If the same gene is expressed in multiple cell types or is absent from one desired cell type, LPD-mediated gene delivery to every cell may have off-target effects. To circumvent this problem, we have tested LPD-mediated gene delivery using various generalized, modified, and retinal cell-specific promoters. We achieved retinal pigment epithelium cell specificity with vitelliform macular dystrophy (VMD2), rod cell specificity with mouse rhodopsin, cone cell specificity with red/green opsin, and ganglion cell specificity with thymocyte antigen promoters. Here we show for the first time that cell-specific promoters enable lipid-based nanoparticles to deliver genes to specific cells of the retina in vivo. This work will inspire investigators in the field of lipid nanotechnology to couple cell-specific promoters to drive expression in a cell- and tissue-specific manner. PMID:27446487

  6. Quercetin Modulates the Effects of Chromium Exposure on Learning, Memory and Antioxidant Enzyme Activity in F1 Generation Mice.

    PubMed

    Halder, Sumita; Kar, Rajarshi; Mehta, Ashish K; Bhattacharya, Swapan K; Mediratta, Pramod K; Banerjee, Basu D

    2016-06-01

    In the present study, we investigated whether chromium (Cr) administered to the dams (F0) during lactation period could affect memory and oxidative stress in F1 generation mice in their adulthood and whether quercetin could modulate these effects. Morris water maze (MWM) was used to test for spatial memory. Passive avoidance task and elevated plus maze were used to test for acquisition and retention memory. Oxidative stress was evaluated by measuring glutathione-S-transferase (GST), catalase activity and malonaldehyde (MDA) levels in the brain tissue. The results of MWM showed that the animals in the Cr-treated group compared to control have better spatial memory that was further enhanced when Cr was administered along with quercetin (50 mg/kg). The elevated plus maze test also showed the Cr-treated group to improve acquisition as well as retention memory compared to control. Co-treatment with quercetin (all doses) also exhibited enhanced acquisition and retention memory compared to control. The passive avoidance task demonstrated no significant improvement in memory in the Cr-treated mice but co-treatment with quercetin (100 mg/kg) showed improved acquisition memory compared to control which was significantly better than the animals treated with chromium alone. GST activity was significantly increased in the Cr-treated animals, and this was further increased in groups treated with Cr and quercetin (all doses). Chromium when administered alone and in combination with quercetin (all doses) significantly reduced MDA levels. However, Cr treatment did not show significant change in catalase activity. Nevertheless, co-treatment with quercetin (25 and 50 mg/kg) resulted in significant decrease in catalase activity. Thus, our study demonstrates that Cr exposure during lactation could be beneficial for pups with respect to augmentation of cognitive function and reduction of oxidative stress. Quercetin could probably enhance this effect to some extent. PMID:26521059

  7. Clinically relevant interaction between warfarin and scuppernongs, a quercetin containing muscadine grape: continued questions surrounding flavonoid-induced warfarin interactions

    PubMed Central

    Woodward, Christopher J; Deyo, Zachariah M; Donahue, Katrina E; Deal, Allison M; Hawes, Emily M

    2014-01-01

    We present a case of clinically relevant and probable interaction between warfarin and scuppernongs in a 73-year-old woman where ingestion of scuppernongs, a variety of quercetin-containing muscadine grapes, over a period of 2 months was associated with elevations in the International Normalised Ratio to supratherapeutic levels. While muscadine grapes and specifically scuppernongs are found primarily in Southeastern USA, the flavonoid in questionand quercetin is found worldwide as a dietary supplement. PMID:24966255

  8. Protective effects of quercetin on cadmium fluoride induced oxidative stress at different intervals of time in mouse liver.

    PubMed

    Zargar, Seema; Siddiqi, Nikhat Jamal; Al Daihan, Sooad Khalaf; Wani, Tanveer A

    2015-01-01

    Quercetin, a member of the flavonoid family is a major antioxidant acquired in humans by food consumption, while Cadmium fluoride (CdF2) is one of the naturally occurring chemicals having adverse effects. The protective effect of quercetin on time dependent oxidative damage induced in mice liver by CdF2 was studied in the following groups of mice consisting of six mice each: (i) control group; (ii) mice treated with single i.p injection of 2 mg/kg bw CdF2 for 24 h; (iii) mice treated with single i.p injection of 2 mg/kg bw CdF2 for 48 h; (iv) mice treated with single i.p injection of quercetin (100 mg/kg bw); (v) mice treated with i.p injection of 100 mg/kg bw of quercetin followed by i.p injection of CdF2 (2 mg/kg bw) for 24 h; and (vi) mice treated with i.p injection of 100mg/kg bw of quercetin followed by CdF2 (2 mg/kg bw) for 48 h. Administration of quercetin two hours before CdF2 significantly reduced the biochemical alterations in reduced glutathione, ascorbic acid, lipid peroxidation, super oxide dismutase, catalase and total protein (p<0.05). Histopathology also showed the protective effect of quercetin. The livers treated with CdF2 were atrophic, markedly nodular, inflamed and necrotic. However, this effect was reduced to a minimum in the mice pre-treated for two hours with quercetin. PMID:25856559

  9. Effects of quercetin, a natural phenolic compound, in the differentiation of human mesenchymal stem cells (MSC) into adipocytes and osteoblasts.

    PubMed

    Casado-Díaz, Antonio; Anter, Jaouad; Dorado, Gabriel; Quesada-Gómez, José Manuel

    2016-06-01

    Natural phenols may have beneficial properties against oxidative stress, which is associated with aging and major chronic aging-related diseases, such as loss of bone mineral mass (osteoporosis) and diabetes. The main aim of this study was to analyze the effect of quercetin, a major nutraceutical compound present in the "Mediterranean diet", on mesenchymal stem-cell (MSC) differentiation. Such cells were induced to differentiate into osteoblasts or adipocytes in the presence of two quercetin concentrations (0.1 and 10μM). Several physiological parameters and the expression of osteoblastogenesis and adipogenesis marker genes were monitored. Quercetin (10μM) inhibited cell proliferation, alkaline phosphatase (ALPL) activity and mineralization, down-regulating the expression of ALPL, collagen type I alpha 1 (COL1A1) and osteocalcin [bone gamma-carboxyglutamate protein (BGLAP)] osteoblastogenesis-related genes in MSC differentiating into osteoblasts. Moreover, in these cultures, CCAAT/enhancer-binding protein alpha (CEBPA) and peroxisome proliferator-activated receptor gamma 2 (PPARG2) adipogenic genes were induced, and cells differentiated into adipocytes were observed. Quercetin did not affect proliferation, but increased adipogenesis, mainly at 10-μM concentration in MSC induced to differentiate to adipocytes. β- and γ-catenin (plakoglobin) nuclear levels were reduced and increased, respectively, in quercetin-treated cultures. This suggests that the effect of high concentration of quercetin on MSC osteoblastic and adipogenic differentiation is mediated via Wnt/β-catenin inhibition. In conclusion, quercetin supplementation inhibited osteoblastic differentiation and promoted adipogenesis at the highest tested concentration. Such possible adverse effects of high quercetin concentrations should be taken into account in nutraceutical or pharmaceutical strategies using such flavonol. PMID:27142748

  10. A combination of methylprednisolone and quercetin is effective for the treatment of cardiac contusion following blunt chest trauma in rats

    PubMed Central

    Demir, F.; Güzel, A.; Katı, C.; Karadeniz, C.; Akdemir, U.; Okuyucu, A.; Gacar, A.; Özdemir, S.; Güvenç, T.

    2014-01-01

    Cardiac contusion is a potentially fatal complication of blunt chest trauma. The effects of a combination of quercetin and methylprednisolone against trauma-induced cardiac contusion were studied. Thirty-five female Sprague-Dawley rats were divided into five groups (n=7) as follows: sham, cardiac contusion with no therapy, treated with methylprednisolone (30 mg/kg on the first day, and 3 mg/kg on the following days), treated with quercetin (50 mg·kg−1·day−1), and treated with a combination of methylprednisolone and quercetin. Serum troponin I (Tn-I) and tumor necrosis factor-alpha (TNF-α) levels and cardiac histopathological findings were evaluated. Tn-I and TNF-α levels were elevated after contusion (P=0.001 and P=0.001). Seven days later, Tn-I and TNF-α levels decreased in the rats treated with methylprednisolone, quercetin, and the combination of methylprednisolone and quercetin compared to the rats without therapy, but a statistical significance was found only with the combination therapy (P=0.001 and P=0.011, respectively). Histopathological degeneration and necrosis scores were statistically lower in the methylprednisolone and quercetin combination group compared to the group treated only with methylprednisolone (P=0.017 and P=0.007, respectively). However, only degeneration scores were lower in the combination therapy group compared to the group treated only with quercetin (P=0.017). Inducible nitric oxide synthase positivity scores were decreased in all treatment groups compared to the untreated groups (P=0.097, P=0.026, and P=0.004, respectively). We conclude that a combination of quercetin and methylprednisolone can be used for the specific treatment of cardiac contusion. PMID:25098616

  11. Protective Effect of Quercetin on Oxidative Stress in Glucose-6-Phosphate Dehydrogenase-Deficient Erythrocytes in Vitro

    PubMed Central

    Jamshidzadeh, Akram; Rezaeian Mehrabadi, Abbas

    2010-01-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficient subjects are vulnerable to oxidative stress. Quercetin, a flavonoids, has been employed as a potent oxygen-free radical scavenger in order to assess the protective effects of quercetin against H2O2-induced oxidative damage in G6PD-deficient and normal human erythrocytes. Erythrocytes of G6PD-deficient (n = 10) and normal (n = 10) subjects were incubated with different concentrations of quercetin. The produced thiobarbituric acid reactive substance (TBARS) and glutathione (GSH) level of erythrocytes were then subsequently measured. Different concentrations of quercetin showed no significant hemolysis, compared with the phosphate buffer solution. Upon challenge with H2O2, there was a significant (p < 0.005) decrease in GSH and an increase in TBARS level in G6PD-deficient erythrocytes. With quercetin, it managed to preserve concentrations of 15 to 75 mM preserved GSH and TBARS levels of normal and G6PD-deficient erythrocytes against H2O2-induced oxidative damage. In addition to its well-established antioxidant effects, quercetin was also found to have cytoprotective properties. PMID:24363724

  12. Metabonomic analysis of quercetin against the toxicity of chronic exposure to a mixture of four organophosphate pesticides in rat plasma.

    PubMed

    Cao, Can; Zeng, Yan; Shi, Haidan; Yang, Shuang; Bao, Wei; Qi, Lei; Liu, Ying; Zhao, Xiujun

    2016-09-01

    1. A metabonomics approach was performed to investigate the effect of quercetin on the toxicity of chronic exposure to a mixture of four organophosphate pesticides (OPs) at their corresponding no-observed-adverse-effect level (NOAEL). The rats were divided into six groups (n = 10/group): control, two different doses of quercetin, OPs mixture and different doses of quercetin plus OPs mixture-treated groups. 2. Nine metabolites, including two quercetin metabolites and seven endogenous metabolites were identified in plasma. The intensities of metabolites significantly changed in the OP mixture-treated group compared with the control group (p < 0.01), such as lysoPE (16:0/0:0), lysoPC (17:0/0:0), lysoPC (15:0/0:0) and 4-pyridoxic acid, significantly increased; by contrast, the intensities of arachidonic acid and citric acid significantly decreased. Anomalous intensity changes in aforementioned metabolites were alleviated in the OP mixture plus 50 mg/kgċbw/d quercetin-treated group compared with the OP mixture-treated group (p < 0.05). 3. The results indicated that quercetin elicited partial protective effects against the toxicity induced by a mixture of OPs, which include regulation of lipid metabolism, improvement of tricarboxylic acid (TCA) cycle disorders, enhancement of antioxidant defence system to protect the liver. PMID:26677787

  13. Quercetin, an in vitro inhibitor of CYP3A, does not contribute to the interaction between nifedipine and grapefruit juice.

    PubMed Central

    Rashid, J; McKinstry, C; Renwick, A G; Dirnhuber, M; Waller, D G; George, C F

    1993-01-01

    Quercetin, a flavonoid present in various fruits, is a potent in vitro inhibitor of CYP3A. Its role in the reported interaction between grapefruit juice and nifedipine has been determined in vivo in humans. Eight healthy volunteers were given in random order 10 mg nifedipine orally, either alone or with 200 ml double strength grapefruit juice, or with 400 mg quercetin. The area under the plasma concentration-time curve (AUC) for nifedipine with grapefruit juice (mean 320 ng ml(-1) h) was increased significantly (P < 0.01) compared with the AUC when nifedipine was given alone (mean 218 ng ml(-1) h). The time to peak plasma concentration for nifedipine with grapefruit juice (1.5 h) was also increased (P < 0.05) compared with control (0.5 h) suggesting delayed absorption. Although quercetin delayed the time to peak nifedipine concentration (1.3 h) it did not alter the AUC of either the parent drug (mean 209 ng ml(-1) h) or its first-pass metabolite. The results suggest that quercetin does not contribute to the effects of grapefruit juice (which contains <10 mg of quercetin 200 ml(-1)) on the metabolism of nifedipine. Oral doses of quercetin, similar to those possible from the ingestion of other fruits such as strawberries, do not produce in vivo inhibition of CYP3A mediated metabolism of nifedipine. PMID:12959295

  14. Amelioration of intracellular stress and reduction of neural tube defects in embryos of diabetic mice by phytochemical quercetin

    PubMed Central

    Cao, Lixue; Tan, Chengyu; Meng, Fantong; Liu, Peiyan; Reece, E. Albert; Zhao, Zhiyong

    2016-01-01

    Diabetes mellitus in early pregnancy causes birth defects, including neural tube defects (NTDs). Hyperglycemia increases production of nitric oxide (NO) through NO synthase 2 (Nos2) and reactive oxygen species (ROS), generating nitrosative and oxidative stress conditions in the embryo. The present study aimed to target nitrosative stress using a naturally occurring Nos2 inhibitor, quercetin, to prevent NTDs in the embryos of diabetic mice. Daily administration of quercetin to diabetic pregnant mice during the hyperglycemia-susceptible period of organogenesis significantly reduced NTDs and cell apoptosis in the embryos, compared with those of vehicle-treated diabetic pregnant mice. Using HPLC-coupled ESI-MS/MS, quercetin metabolites, including methylated and sulfonylated derivatives, were detected in the conceptuses. The methylated metabolite, 3-O-methylquercetin, was shown to reduce ROS level in embryonic stem cells cultured in high glucose. Quercetin treatment decreased the levels of Nos2 expression, protein nitrosylation, and protein nitration, alleviating nitrosative stress. Quercetin increased the expression of superoxide dismutase 1 and 2, and reduced the levels of oxidative stress markers. Expression of genes of redox regulating enzymes and DNA damage repair factors was upregulated. Our study demonstrates that quercetin ameliorates intracellular stresses, regulates gene expression, and reduces embryonic malformations in diabetic pregnancy. PMID:26887929

  15. Improvement of memory recall by quercetin in rodent contextual fear conditioning and human early-stage Alzheimer's disease patients.

    PubMed

    Nakagawa, Toshiyuki; Itoh, Masanori; Ohta, Kazunori; Hayashi, Yuichi; Hayakawa, Miki; Yamada, Yasushi; Akanabe, Hiroshi; Chikaishi, Tokio; Nakagawa, Kiyomi; Itoh, Yoshinori; Muro, Takato; Yanagida, Daisuke; Nakabayashi, Ryo; Mori, Tetsuya; Saito, Kazuki; Ohzawa, Kaori; Suzuki, Chihiro; Li, Shimo; Ueda, Masashi; Wang, Miao-Xing; Nishida, Emika; Islam, Saiful; Tana; Kobori, Masuko; Inuzuka, Takashi

    2016-06-15

    Patients with Alzheimer's disease (AD) experience a wide array of cognitive deficits, which typically include the impairment of explicit memory. In previous studies, the authors reported that a flavonoid, quercetin, reduces the expression of ATF4 and delays memory deterioration in an early-stage AD mouse model. In the present study, the effects of long-term quercetin intake on memory recall were assessed using contextual fear conditioning in aged wild-type mice. In addition, the present study examined whether memory recall was affected by the intake of quercetin-rich onion (a new cultivar of hybrid onion 'Quergold') powder in early-stage AD patients. In-vivo analysis indicated that memory recall was enhanced in aged mice fed a quercetin-containing diet. Memory recall in early-stage AD patients, determined using the Revised Hasegawa Dementia Scale, was significantly improved by the intake of quercetin-rich onion (Quergold) powder for 4 weeks compared with the intake of control onion ('Mashiro' white onion) powder. These results indicate that quercetin might influence memory recall. PMID:27145228

  16. Quercetin protects primary human osteoblasts exposed to cigarette smoke through activation of the antioxidative enzymes HO-1 and SOD-1.

    PubMed

    Braun, Karl F; Ehnert, Sabrina; Freude, Thomas; Egaña, José T; Schenck, Thilo L; Buchholz, Arne; Schmitt, Andreas; Siebenlist, Sebastian; Schyschka, Lilianna; Neumaier, Markus; Stöckle, Ulrich; Nussler, Andreas K

    2011-01-01

    Smokers frequently suffer from impaired fracture healing often due to poor bone quality and stability. Cigarette smoking harms bone cells and their homeostasis by increased formation of reactive oxygen species (ROS). The aim of this study was to investigate whether Quercetin, a naturally occurring antioxidant, can protect osteoblasts from the toxic effects of smoking. Human osteoblasts exposed to cigarette smoke medium (CSM) rapidly produced ROS and their viability decreased concentration- and time-dependently. Co-, pre- and postincubation with Quercetin dose-dependently improved their viability. Quercetin increased the expression of the anti-oxidative enzymes heme-oxygenase- (HO-) 1 and superoxide-dismutase- (SOD-) 1. Inhibiting HO-1 activity abolished the protective effect of Quercetin. Our results demonstrate that CSM damages human osteoblasts by accumulation of ROS. Quercetin can diminish this damage by scavenging the radicals and by upregulating the expression of HO-1 and SOD-1. Thus, a dietary supplementation with Quercetin could improve bone matter, stability and even fracture healing in smokers. PMID:22203790

  17. Beneficial effects of quercetin-iron complexes on serum and tissue lipids and redox status in obese rats.

    PubMed

    Imessaoudene, Asmahan; Merzouk, Hafida; Berroukeche, Farid; Mokhtari, Nassima; Bensenane, Bachir; Cherrak, Sabri; Merzouk, Sid Ahmed; Elhabiri, Mourad

    2016-03-01

    Obesity is characterized by iron deficiency, carbohydrate and fat alterations as well as oxidative stress. Iron status monitoring is recommended because of the conventional oral iron preparations that frequently exacerbate the already present oxidative stress. Iron complexation by natural antioxidants can be exploited. We herein investigated the metabolic effects of quercetin (25 mg/kg/day), iron (2.5 mg Fe/kg/day) or quercetin-iron complexes (molar ratio 5:1; 25 mg/2.5 mg/kg/day) in animal models of obesity. Our results emphasized that obese rats displayed metabolic alterations that were worsened by iron supplementation. In contrast, quercetin used alone or as iron complex clearly prevented adipose fat accumulation and alleviated the hyperglycemia, hyperlipidemia, liver steatosis and oxidative stress. In addition, it induced a modulation of lipase activities in obese rats. Interestingly, quercetin-iron complexes showed enhanced beneficial effects such as a corrected iron deficiency in obese rats when compared to quercetin alone. In conclusion, antianemic, hypoglycemic, hypolipidemic and antioxidative effects of the quercetin-iron complexes shed a light on their beneficial use against obesity-related metabolic alterations. PMID:26895671

  18. Neurite Outgrowth and Neuroprotective Effects of Quercetin from Caesalpinia mimosoides Lamk. on Cultured P19-Derived Neurons.

    PubMed

    Tangsaengvit, Napat; Kitphati, Worawan; Tadtong, Sarin; Bunyapraphatsara, Nuntavan; Nukoolkarn, Veena

    2013-01-01

    Quercetin has been isolated for the first time from ethyl acetate extract of Caesalpinia mimosoides Lamk. C. mimosoides Lamk. (Fabaceae) or Cha rueat (Thai name) is an indigenous plant found in mixed deciduous forest in northern and north-eastern parts of Thailand. Thai rural people consume its young shoots and leaves as a fresh vegetable, as well as it is used for medicinal purposes.The antioxidant capacity in terms of radical scavenging activity of quercetin was determined as IC50 of 3.18 ± 0.07 µg/mL, which was higher than that of Trolox and ascorbic acid (12.54 ± 0.89 and 10.52 ± 0.48 µg/mL, resp.). The suppressive effect of quercetin on both purified and cellular acetylcholinesterase (AChE) enzymes was investigated as IC50 56.84 ± 2.64 and 36.60 ± 2.78 µg/mL, respectively. In order to further investigate the protective ability of quercetin on neuronal cells, P19-derived neurons were used as a neuronal model in this study. As a result, quercetin at a very low dose of 1 nM enhanced survival and induced neurite outgrowth of P19-derived neurons. Furthermore, this flavonoid also possessed significant protection against oxidative stress induced by serum deprivation. Altogether, these findings suggest that quercetin is a multifunctional compound and promising valuable drugs candidate for the treatment of neurodegenerative disease. PMID:23840266

  19. Protective effects of quercetin and taraxasterol against H2O2-induced human umbilical vein endothelial cell injury in vitro

    PubMed Central

    YANG, DONGWEI; LIU, XINYE; LIU, MIN; CHI, HAO; LIU, JIRONG; HAN, HUAMIN

    2015-01-01

    Due to the association between inflammation and endothelial dysfunction in atherosclerosis, the blockage of the inflammatory process that occurs on the endothelial cells may be a useful way of preventing atherosclerosis. In the present study, human umbilical vein endothelial cells (HUVECs) were used to investigate the protective effects of quercetin and taraxasterol against H2O2-induced oxidative damage and inflammation. HUVECs were pretreated with quercetin or taraxasterol at concentrations ranging between 0 and 210 µM for 12 h, prior to being administered different concentrations of H2O2 for 4 h. Cell viability and levels of apoptosis were assessed through cell counting kit-8 (CCK-8) and terminal deoxynucleotidyl transferase dUTP nick end labeling assays, respectively, to determine the injury to the HUVECs. The viability loss in the H2O2-induced HUVECs was markedly restored in a concentration-dependent manner by pretreatment with quercetin or taraxasterol. This effect was accompanied by significantly decreased expression of vascular cell adhesion molecule 1 (VCAM-1) and cluster of differentiation (CD)80 for taraxasterol and that of CD80 for quercetin. In conclusion, the present study showed the protective effects of quercetin and taraxasterol against cell injury and inflammation in HUVECs and indicated that the effects were mediated via the downregulation of VCAM-1 and CD80 expression. This study has therefore served as a preliminary investigation on the anti-atherosclerotic and cardiovascular protective effects of quercetin and taraxasterol as dietary supplements. PMID:26622474

  20. Selection of filamentous fungi of the Beauveria genus able to metabolize quercetin like mammalian cells

    PubMed Central

    de M. B. Costa, Eula Maria; Pimenta, Fabiana Cristina; Luz, Wolf Christian; de Oliveira, Valéria

    2008-01-01

    Microbial biotransformations constitute an important alternative as models for drug metabolism study in mammalians and have been used for the industrial synthesis of chemicals with pharmaceutical purposes. Several microorganisms with unique biotransformation ability have been found by intensive screening and put in commercial applications. Ten isolates of Beauveria sp genus filamentous fungi, isolated from soil in the central Brazil, and Beauveria bassiana ATCC 7159 were evaluated for their capability of quercetin biotransformation. Biotransformation processes were carried out for 24 up to 96 hours and monitored by mass spectrometry analyses of the culture broth. All strains were able to metabolize quercetin, forming mammalian metabolites. The results were different from those presented by other microorganisms previously utilized, attrackting attention because of the great diversity of reactions. Methylated, sulphated, monoglucuronidated, and glucuronidated conjugated metabolites were simultaneously detected. PMID:24031237

  1. Supraphysiological Levels of Quercetin Glycosides are Required to Alter Mineralization in Saos2 Cells

    PubMed Central

    Nash, Leslie A.; Peters, Sandra J.; Sullivan, Philip J.; Ward, Wendy E.

    2016-01-01

    Flavonoid intake is positively correlated to bone mineral density (BMD) in women. Flavonoids such as quercetin exhibit strong anti-oxidant and anti-inflammatory activity that may be beneficial for bone health. Quercetin, previously shown to positively influence osteoblasts, is metabolized into glycosides including rutin and hyperoside. We compared the effects of these glycosides on mineralization in human osteoblast (Saos2) cells. Administration of rutin (≥25 µM) and hyperoside (≥5 µM) resulted in higher mineral content, determined using the alizarin red assay. This was accompanied by higher alkaline phosphatase activity with no cell toxicity. The expression of osteopontin, sclerostin, TNFα and IL6, known stimuli for decreasing osteoblast activity, were reduced with the addition of rutin or hyperoside. In summary, rutin and hyperoside require supraphysiological levels, when administered individually, to positively influence osteoblast activity. This information may be useful in developing nutraceuticals to support bone health. PMID:27136576

  2. Data for induction of cytotoxic response by natural and novel quercetin glycosides.

    PubMed

    Haskins, Alexis H; Su, Cathy; Engen, Anya; Salinas, Victoria A; Maeda, Junko; Uesaka, Mitsuru; Aizawa, Yasushi; Kato, Takamitsu A

    2016-03-01

    The flavonoids quercetin, and its natural glycosides isoquercetin and rutin, are phytochemicals commonly consumed in plant-derived foods and used as a food beverage additive. Semi-synthetic maltooligosyl isoquercetin, monoglucosyl rutin and maltooligosyl rutin were developed by synthetic glycosylation to improve their water solubility for food and other applications. Using a system of Chinese hamster ovary (CHO) cells, this study examined the differences in cytotoxic responses induced by short and continuous exposure of natural and synthetic flavonoids. By assessing cell viability after short term exposure and clonogenicity with continuous exposure under various flavonoids, quercetin aglycone is confirmed to be the most cytotoxic flavonoids, and heavily glucosylated maltooligosyl rutin was the least cytotoxic. The other heavily glucosylated maltooligosyl isoquercetin showed intermediate cytotoxicity and similar toxicity as isoquercetin. PMID:26862569

  3. Supraphysiological Levels of Quercetin Glycosides are Required to Alter Mineralization in Saos2 Cells.

    PubMed

    Nash, Leslie A; Peters, Sandra J; Sullivan, Philip J; Ward, Wendy E

    2016-01-01

    Flavonoid intake is positively correlated to bone mineral density (BMD) in women. Flavonoids such as quercetin exhibit strong anti-oxidant and anti-inflammatory activity that may be beneficial for bone health. Quercetin, previously shown to positively influence osteoblasts, is metabolized into glycosides including rutin and hyperoside. We compared the effects of these glycosides on mineralization in human osteoblast (Saos2) cells. Administration of rutin (≥25 µM) and hyperoside (≥5 µM) resulted in higher mineral content, determined using the alizarin red assay. This was accompanied by higher alkaline phosphatase activity with no cell toxicity. The expression of osteopontin, sclerostin, TNFα and IL6, known stimuli for decreasing osteoblast activity, were reduced with the addition of rutin or hyperoside. In summary, rutin and hyperoside require supraphysiological levels, when administered individually, to positively influence osteoblast activity. This information may be useful in developing nutraceuticals to support bone health. PMID:27136576

  4. Nitrosyl hydride (HNO) replaces dioxygen in nitroxygenase activity of manganese quercetin dioxygenase

    PubMed Central

    Kumar, Murugaeson R.; Zapata, Adrian; Ramirez, Alejandro J.; Bowen, Sara K.; Francisco, Wilson A.; Farmer, Patrick J.

    2011-01-01

    Quercetin dioxygenase (QDO) catalyzes the oxidation of the flavonol quercetin with dioxygen, cleaving the central heterocyclic ring and releasing CO. The QDO from Bacillus subtilis is unusual in that it has been shown to be active with several divalent metal cofactors such as Fe, Mn, and Co. Previous comparison of the catalytic activities suggest that Mn(II) is the preferred cofactor for this enzyme. We herein report the unprecedented substitution of nitrosyl hydride (HNO) for dioxygen in the activity of Mn-QDO, resulting in the incorporation of both N and O atoms into the product. Turnover is demonstrated by consumption of quercetin and other related substrates under anaerobic conditions in the presence of HNO-releasing compounds and the enzyme. As with dioxygenase activity, a nonenzymatic base-catalyzed reaction of quercetin with HNO is observed above pH 7, but no enhancement of this basal reactivity is found upon addition of divalent metal salts. Unique and regioselective N-containing products (14N/15N) have been characterized by MS analysis for both the enzymatic and nonenzymatic reactions. Of the several metallo-QDO enzymes examined for nitroxygenase activity under anaerobic condition, only the Mn(II) is active; the Fe(II) and Co(II) substituted enzymes show little or no activity. This result represents an enzymatic catalysis which we denote nitroxygenase activity; the unique reactivity of the Mn-QDO suggests a metal-mediated electron transfer mechanism rather than metal activation of the substrate’s inherent base-catalyzed reactivity. PMID:22084064

  5. Evaluation of inhibitory effects of caffeic acid and quercetin on human liver cytochrome p450 activities.

    PubMed

    Rastogi, Himanshu; Jana, Snehasis

    2014-12-01

    When herbal drugs and conventional allopathic drugs are used together, they can interact in our body which can lead to the potential for herb-drug interactions. This work was conducted to evaluate the herb-drug interaction potential of caffeic acid and quercetin mediated by cytochrome P450 (CYP) inhibition. Human liver microsomes (HLMs) were added to each selective probe substrates of cytochrome P450 enzymes with or without of caffeic acid and quercetin. IC50 , Ki values, and the types of inhibition were determined. Both caffeic acid and quercetin were potent competitive inhibitors of CYP1A2 (Ki = 1.16 and 0.93 μM, respectively) and CYP2C9 (Ki = 0.95 and 1.67 μM, respectively). Caffeic acid was a potent competitive inhibitor of CYP2D6 (Ki = 1.10 μM) and a weak inhibitor of CYP2C19 and CYP3A4 (IC50  > 100 μM). Quercetin was a potent competitive inhibitor of CYP 2C19 and CYP3A4 (Ki = 1.74 and 4.12 μM, respectively) and a moderate competitive inhibitor of CYP2D6 (Ki = 18.72 μM). These findings might be helpful for safe and effective use of polyphenols in clinical practice. Our data indicated that it is necessary to study the in vivo interactions between drugs and pharmaceuticals with dietary polyphenols. PMID:25196644

  6. Therapeutic role of quercetin on oxidative damage induced by acrylamide in rat brain.

    PubMed

    Zargar, Seema; Siddiqi, Nikhat Jamal; Ansar, Sabah; Alsulaimani, Maha Saleh; El Ansary, Afaf K

    2016-09-01

    Context Quercetin (QE), a bioflavonoid present abundantly in fruits and vegetables, has been reported to possess antioxidant properties. Acrylamide (ACR) is formed in foods during cooking and is known to be neurotoxic. Objective The present study was designed to evaluate the protective effect of QE against neurotoxicity induced by ACR. Materials and methods Four groups of Wistar rats consisting of six rats each: (i) control group; (ii) acrylamide treated group (50 mg/kg body weight as single dose); (iii) quercetin group: rats were treated intraperitoneally (i.p.) with QE (10 mg/kg body weight alone every day for 5 d); (iv) quercetin + acrylamide group: quercetin (10 mg/kg bw) was given i.p. every day for 5 d followed by acrylamide i.p. injection (50 mg/kg bw) on fifth day (single dose). Rats were killed after 48 h. Results Administration of ACR (50 mg/kg bw) in Wistar rats resulted in significant increase of dopamine, interferon-γ and 8-hydroxyguanosine with concomitant decrease of serotonin (p < 0.001) in the rat brain. Treatment of rats with QE intraperitonealy (10 mg/kg body weight) before ACR assault resulted in the diminution of ACR-mediated neurotoxicity as evident from decreased levels of dopamine, interferon-γ (p < 0.001) and 8-hydroxyguanosine with concomitant restoration of serotonin levels (p < 0.001). Discussion and conclusion On the basis of the above results, the present study suggests that quercetin may be a potential therapeutic agent for restoration of oxidative damage to neurons. PMID:26730789

  7. Cancer

    MedlinePlus

    Cancer begins in your cells, which are the building blocks of your body. Normally, your body forms ... be benign or malignant. Benign tumors aren't cancer while malignant ones are. Cells from malignant tumors ...

  8. Exploring the antioxidant property of bioflavonoid quercetin in preventing DNA glycation: A calorimetric and spectroscopic study

    SciTech Connect

    Sengupta, Bidisa . E-mail: bidisa@fy.chalmers.se; Uematsu, Takashi; Jacobsson, Per; Swenson, Jan

    2006-01-06

    Reducing sugars for example glucose, fructose, etc., and their phosphate derivatives non-enzymatically glycate biological macromolecules (e.g., proteins, DNA and lipids) and is related to the production of free radicals. Here we present a novel study, using differential scanning calorimetry (DSC) along with UV/Vis absorption and photon correlation spectroscopy (PCS), on normal and glycated human placenta DNA and have explored the antioxidant property of the naturally occurring polyhydroxy flavone quercetin (3,3',4',5,7-pentahydroxyflavone) in preventing the glycation. The decrease in the absorption intensity of DNA in presence of sugars clearly indicates the existence of sugar molecules between the two bases of a base pair in the duplex DNA molecule. Variations were perceptible in the PCS relaxation profiles of normal and glycated DNA. The melting temperature of placenta DNA was decreased when glycated suggesting a decrease in the structural stability of the double-stranded glycated DNA. Our DSC and PCS data showed, for the first time, that the dramatic changes in the structural properties of glycated DNA can be prevented to a significant extent by adding quercetin. This study provides valuable insights regarding the structure, function, and dynamics of normal and glycated DNA molecules, underlying the manifestation of free radical mediated diseases, and their prevention using therapeutically active naturally occurring flavonoid quercetin.

  9. Complexation of quercetin with three kinds of cyclodextrins: An antioxidant study

    NASA Astrophysics Data System (ADS)

    Jullian, Carolina; Moyano, Lorena; Yañez, Claudia; Olea-Azar, Claudio

    2007-05-01

    The slightly water-soluble flavonoid quercetin (QUE) and its inclusion with either β-cyclodextrin (βCD), hydroxypropyl-β-cyclodextrin (HP-βCD) or sulfobutyl ether-β-cyclodextrin (SBE-βCD) were investigated. The stoichiometric ratios and stability constants describing the extent of formation of the complexes have been determined by phase-solubility measurements; in all cases type-A L diagrams have been obtained (soluble 1:1 complexes). The results showed that the inclusion ability of βCD and its derivatives was the order: SBE-βCD > HP-βCD > βCD. Kinetic studies of DPPH rad with QUE and CDs complexes were done. The results obtained indicated that the QUE-SBE-βCD complex was the most reactive form. The scavenging capability of QUE and CDs complexes with DPPH rad and galvinoxyl was studied using ESR spectroscopy. All complexes showed a higher scavenging capability with both radicals, compare quercetin in water. Beside, these results indicated that the complexes formed maintained the quercetin antioxidant activity.

  10. Cross-linked chitosan/liposome hybrid system for the intestinal delivery of quercetin.

    PubMed

    Caddeo, Carla; Díez-Sales, Octavio; Pons, Ramon; Carbone, Claudia; Ennas, Guido; Puglisi, Giovanni; Fadda, Anna Maria; Manconi, Maria

    2016-01-01

    Quercetin is a flavonoid with antioxidant/anti-inflammatory properties, poorly absorbed when administered orally. To increase its bioavailability and optimize its release in the intestine, a hybrid system made of liposomes coated with cross-linked chitosan, named TPP-chitosomes, was developed and characterized by light scattering, transmission electron microscopy, differential scanning calorimetry, X-ray powder diffraction and Turbiscan® technology. The TPP-chitosomes were nanosized (∼180 nm), fairly spherical in shape and unilamellar. The actual coating of the surface of liposomes with the cross-linked chitosan was demonstrated by Small-Angle X-ray Scattering. The release of quercetin in simulated gastric and intestinal pH was investigated, the results showing that the system provided resistance to acidic conditions, and promoted the release in alkaline pH, mimicking the intestinal environment. The proposed hybrid system represents a promising combination of nanovesicles and chitosan for the delivery of quercetin to the intestine in the therapy of oxidative stress/inflammation related disorders. PMID:26397912

  11. Camelina sativa defatted seed meal contains both alkyl sulfinyl glucosinolates and quercetin that synergize bioactivity.

    PubMed

    Das, Nilanjan; Berhow, Mark A; Angelino, Donato; Jeffery, Elizabeth H

    2014-08-20

    Camelina sativa L. Crantz is under development as a novel oilseed crop, yet bioefficacy of camelina phytochemicals is unknown. Defatted camelina seed meal contains two major aliphatic glucosinolates (GSLs), glucoarabin (9-(methylsulfinyl)nonylglucosinolate; GSL 9) and glucocamelinin (10-(methylsulfinyl)decylglucosinolate; GSL 10), with traces of a third, 11(methylsulfinyl)undecylglucosinolate and several flavonoids, mostly quercetin glycosides. In Hepa1c1c7 cells, hydrolyzed GSLs (hGSLs) 9 and 10 upregulated the phase II detoxification enzyme quinone reductase (NQO1), with no effect on cytochrome P450 (CYP) 1A1 activity. Isobologram graphs revealed synergy of NQO1 induction for a combination of hGSL 9 and quercetin. These findings suggest that defatted camelina seed meal should be evaluated for anticancer activity, similar to broccoli and other Brassicaceae family members. Interestingly, synergy of NQO1 induction was also seen for physiologically relevant doses of sulforaphane (SF) and quercetin, two key bioactives present in broccoli. This suggests that SF within broccoli may be more potent than purified SF. PMID:25050614

  12. Human exposure modelling of quercetin in onions (Allium cepa L.) following thermal processing.

    PubMed

    Harris, S; Brunton, N; Tiwari, U; Cummins, E

    2015-11-15

    Post-harvest treatment can influence levels of secondary metabolites in fruits and vegetables. Onions contain high levels of quercetin but are commonly heat-treated before consumption. Hence, the objective of this study was to examine the effect of cooking treatments on the flavonoid (3,4'-Qdg and 4'-Qmg) concentrations in onion and to determine, by simulation modelling, probable human exposure. Onion samples (n=3) were cooked using three processes (fry, bake and steam) for three time intervals (5, 10 and 15 min). Frying (<10 min) was the ideal cooking method which retained concentrations of 3,4'-Qdg and 4'-Qmg at >50%. Thermal processing (>10 min) was shown to decrease quercetin content in all samples. The simulation model predicted human absorption and exposure. Steaming (15 min) resulted in the lowest quercetin exposure, with mean values of 4000 and 400 μg/day for 3,4'-Qdg and 4'-Qmg, respectively. Untreated onions had mean exposures of 14,000 and 3000 μg/day for 3,4'-Qdg and 4'-Qmg, respectively. PMID:25977008

  13. Quercetin targets the interaction of calcineurin with LxVP-type motifs in immunosuppression.

    PubMed

    Zhao, Yane; Zhang, Jin; Shi, Xiaoyu; Li, Jing; Wang, Rui; Song, Ruiwen; Wei, Qun; Cai, Huaibin; Luo, Jing

    2016-08-01

    Calcineurin (CN) is a unique calcium/calmodulin (CaM)-activated serine/threonine phosphatase. To perform its diverse biological functions, CN communicates with many substrates and other proteins. In the physiological activation of T cells, CN acts through transcriptional factors belonging to the NFAT family and other transcriptional effectors. The classic immunosuppressive drug cyclosporin A (CsA) can bind to cyclophilin (CyP) and compete with CN for the NFAT LxVP motif. CsA has debilitating side effects, including nephrotoxicity, hypertension and tremor. It is desirable to develop alternative immunosuppressive agents. To this end, we first tested the interactions between CN and the LxVP-type substrates, including endogenous regulators of calcineurin (RCAN1) and NFAT. Interestingly, we found that quercetin, the primary dietary flavonol, can inhibit the activity of CN and significantly disrupt the associations between CN and its LxVP-type substrates. We then validated the inhibitory effects of quercetin on the CN-NFAT interactions in cell-based assays. Further, quercetin also shows dose-dependent suppression of cytokine gene expression in mouse spleen cells. These data raise the possibility that the interactions of CN with its LxVP-type substrates are potential targets for immunosuppressive agents. PMID:27109380

  14. Apigenin and quercetin promote. Delta. pH-dependent accumulation of IAA in membrane vesicles

    SciTech Connect

    Woolard, D.D.; Clark, K.A. )

    1990-05-01

    Flavonoids may act as regulators of polar auxin transport. In the presence of a pH gradient (pH 8{sub in}/6{sub out}) the flavonoids quercetin and apigenin, as well as the synthetic herbicide napthylphthalamic acid (NPA), promote the accumulation of IAA in membrane vesicles from dark-grown zucchini hypocotyls. Simultaneous accumulation of {sup 3}H-IAA (10 nM) and {sup 14}C-butyric acid (5 {mu}M; included as a pH probe) was determined by a filtration assay after incubating the vesicles with 3 nM to 100 {mu}M quercetin, apigenin, NPA or unlabeled IAA. Maximal stimulation (% of Control) was observed with 3 {mu}M NPA (130%), 1 {mu}M quercetin (120%), or 3 {mu}M apigenin (115%); {Delta}pH was not affected by these concentrations. As reported by others, IAA uptake was saturable: 1 {mu}M unlabeled IAA eliminated {Delta}pH-dependent uptake of {sup 3}H-IAA without altering {Delta}pH. However, at 30 to 100 {mu}M, every compound tested collapsed the imposed pH gradient and therefore abolished specific {sup 3}H-IAA uptake.

  15. Characterization of putative receptors specific for quercetin on bovine aortic smooth-muscle cells

    SciTech Connect

    Yu, S.C.; Becker, C.G.

    1986-03-01

    The authors have reported that tobacco glycoprotein (TGP), rutin-bovine serum albumin conjugates (R-BSA), quercetin, and chlorogenic acid are mitogenic for bovine aortic smooth-muscle cells (SMC). To investigate whether there are binding sites or receptors for these polyphenol-containing molecules on SMC, the authors have synthesized /sup 125/I-labeled rutin-bovine serum albumin ((/sup 125/I)R-BSA) of high specific activity (20 Ci/mmol). SMC were isolated from a bovine thoracic aorta and maintained in Eagle's minimum essential medium with 10% calf serum in culture. These SMC at early subpassages were suspended (3-5 x 10/sup 7/ cells/ml) in phosphate-buffered saline and incubated with (/sup 125/I)R-BSA (10 pmol) in the presence or absence of 200-fold unlabeled R-BSA, TGP, BSA, rutin, quercetin or related polyphenols, and catecholamines. Binding of (/sup 125/I)R-BSA to SMC was found to be reproducible and the radioligand was displaced by R-BSA, and also by TGP, rutin, quercetin, and chlorogenic acid, but not by BSA, ellagic acid, naringin, hesperetin, dopamine, epinephrine, or isoproterenol. The binding was saturable, reversible, and pH-dependent. These results demonstrate the presence of specific binding sites for quercetinon arterial SMC.

  16. Inhibition of the organic anion-transporting polypeptide 1B1 by quercetin: an in vitro and in vivo assessment

    PubMed Central

    Wu, Lan-Xiang; Guo, Cheng-Xian; Chen, Wang-Qing; Yu, Jing; Qu, Qiang; Chen, Yao; Tan, Zhi-Rong; Wang, Guo; Fan, Lan; Li, Qing; Zhang, Wei; Zhou, Hong-Hao

    2012-01-01

    AIM To investigate the effect of quercetin on organic anion transporting polypeptide 1B1 (OATP1B1) activities in vitro and on the pharmacokinetics of pravastatin, a typical substrate for OATP1B1 in healthy Chinese-Han male subjects. METHODS Using human embryonic kidney 293 (HEK293) cells stably expressing OATP1B1, we observed the effect of quercetin on OATP1B1-mediated uptake of estrone-3-sulphate (E3S) and pravastatin. The influence of quercetin on the pharmacokinetics of pravastatin was measured in 16 healthy Chinese-Han male volunteers receiving a single dose of pravastatin (40 mg orally) after co-administration of placebo or 500 mg quercetin capsules (once daily orally for 14 days). RESULTS Quercetin competitively inhibited OATP1B1-mediated E3S uptake with a Ki value of 17.9 ± 4.6 µm and also inhibited OATP1B1-mediated pravastatin uptake in a concentration dependent manner (IC50, 15.9 ± 1.4 µm). In healthy Chinese-Han male subjects, quercetin increased the pravastatin area under the plasma concentration – time curve (AUC(0,10 h) and the peak plasma drug concentration (Cmax) to 24% (95% CI 15, 32%, P < 0.001) and 31% (95% CI 20, 42%, P < 0.001), respectively. After administration of quercetin, the elimination half-life (t1/2) of pravastatin was prolonged by 14% (95% CI 4, 24%, P = 0.027), with no change in the time to reach Cmax (tmax). Moreover, quercetin decreased the apparent clearance (CL/F) of pravastatin by 18% (95% CI 75, 89%, P < 0.001). CONCLUSIONS These findings suggest that quercetin inhibits the OATP1B1-mediated transport of E3S and pravastatin in vitro and also has a modest inhibitory influence on the pharmacokinetics of pravastatin in healthy Chinese-Han male volunteers. The effects of quercetin on other OATP1B1 substrate drugs deserve further investigation. PMID:22114872

  17. Flavonoid (myricetin, quercetin, kaempferol, luteolin, and apigenin) content of edible tropical plants.

    PubMed

    Miean, K H; Mohamed, S

    2001-06-01

    Studies were conducted on the flavonoids (myricetin, quercetin, kaempferol, luteolin, and apigenin) contents of 62 edible tropical plants. The highest total flavonoids content was in onion leaves (1497.5 mg/kg quercetin, 391.0 mg/kg luteolin, and 832.0 mg/kg kaempferol), followed by Semambu leaves (2041.0 mg/kg), bird chili (1663.0 mg/kg), black tea (1491.0 mg/kg), papaya shoots (1264.0 mg/kg), and guava (1128.5 mg/kg). The major flavonoid in these plant extracts is quercetin, followed by myricetin and kaempferol. Luteolin could be detected only in broccoli (74.5 mg/kg dry weight), green chili (33.0 mg/kg), bird chili (1035.0 mg/kg), onion leaves (391.0 mg/kg), belimbi fruit (202.0 mg/kg), belimbi leaves (464.5 mg/kg), French bean (11.0 mg/kg), carrot (37.5 mg/kg), white radish (9.0 mg/kg), local celery (80.5 mg/kg), limau purut leaves (30.5 mg/kg), and dried asam gelugur (107.5 mg/kg). Apigenin was found only in Chinese cabbage (187.0 mg/kg), bell pepper (272.0 mg/kg), garlic (217.0 mg/kg), belimbi fruit (458.0 mg/kg), French peas (176.0 mg/kg), snake gourd (42.4 mg/kg), guava (579.0 mg/kg), wolfberry leaves (547.0 mg/kg), local celery (338.5 mg/kg), daun turi (39.5 mg/kg), and kadok (34.5 mg/kg). In vegetables, quercetin glycosides predominate, but glycosides of kaempferol, luteolin, and apigenin are also present. Fruits contain almost exclusively quercetin glycosides, whereas kaempferol and myricetin glycosides are found only in trace quantities. PMID:11410016

  18. T cell-specific inhibition of multiple apoptotic pathways blocks negative selection and causes autoimmunity

    PubMed Central

    Burger, Megan L; Leung, Kenneth K; Bennett, Margaux J; Winoto, Astar

    2014-01-01

    T cell self-tolerance is thought to involve peripheral tolerance and negative selection, involving apoptosis of autoreactive thymocytes. However, evidence supporting an essential role for negative selection is limited. Loss of Bim, a Bcl-2 BH3-only protein essential for thymocyte apoptosis, rarely results in autoimmunity on the C57BL/6 background. Mice with T cell-specific over-expression of Bcl-2, that blocks multiple BH3-only proteins, are also largely normal. The nuclear receptor Nur77, also implicated in negative selection, might function redundantly to promote apoptosis by associating with Bcl-2 and exposing its potentially pro-apoptotic BH3 domain. Here, we report that T cell-specific expression of a Bcl2 BH3 mutant transgene results in enhanced rescue of thymocytes from negative selection. Concomitantly, Treg development is increased. However, aged BH3 mutant mice progressively accumulate activated, autoreactive T cells, culminating in development of multi-organ autoimmunity and lethality. These data provide strong evidence that negative selection is crucial for establishing T cell tolerance. DOI: http://dx.doi.org/10.7554/eLife.03468.001 PMID:25182415

  19. Light-regulated and cell-specific methylation of the maize PEPC promoter

    PubMed Central

    Tolley, Ben J.; Woodfield, Helen; Wanchana, Samart; Bruskiewich, Richard; Hibberd, Julian M.

    2012-01-01

    The molecular mechanisms governing PEPC expression in maize remain to be fully defined. Differential methylation of a region in the PEPC promoter has been shown to correlate with transcript accumulation, however, to date, investigations into the role of DNA methylation in maize PEPC expression have relied on the use of methylation-sensitive restriction enzymes. Bisulphite sequencing was used here to provide a single-base resolution methylation map of the maize PEPC promoter. It is shown that four cytosine residues in the PEPC promoter are heavily methylated in maize root tissue. In leaves, de-methylation of these cytosines is dependent on illumination and is coincident with elevated PEPC expression. Furthermore, light-regulated de-methylation of these cytosines occurs only in mesophyll cells. No methylation was discovered in the 0.6 kb promoter required for mesophyll-specific expression indicating that cytosine methylation is not required to direct the cell-specificity of PEPC expression. This raises interesting questions regarding the function of the cell-specific cytosine de-methylation observed in the upstream region of the PEPC promoter. PMID:22143916

  20. Ontogenesis and cell specific localization of Fas ligand expression in the rat testis.

    PubMed

    D'Abrizio, Piera; Baldini, Enke; Russo, Paola F; Biordi, Leda; Graziano, Filomena M; Rucci, Nadia; Properzi, Giuliana; Francavilla, Sandro; Ulisse, Salvatore

    2004-10-01

    Over the past few years, a number of experimental evidences suggested the involvement of Fas Ligand (FasL) expressing Sertoli cells to induce apoptosis of Fas bearing germ cells. However, the FasL expression during testicular development and its cell specific localization within the testis is still a matter of debate. In the present study, we have monitored FasL expression during rat testis development by semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) and evaluated cell specific localization of FasL expression, by in situ RT-PCR and immunohistochemistry, on adult rat testis. RT-PCR analysis, performed on total RNA from rat testes obtained from 1 day up to 1-year-old animals, demonstrated the presence of FasL transcripts at all developmental stages examined. In situ RT-PCR analysis clearly indicated the presence of FasL mRNA in Sertoli cells of adult testis, while we could never detect FasL transcripts in germ cells. Immunohistochemistry experiments showed a strong immunostaining for FasL in Sertoli cells of adult testis and again, no immunopositivity was observed in germ cells. In conclusion, our data suggest that FasL expression in rat testis is present from the early postnatal days up to the adult, and the Sertoli cells is the main FasL expressing cell within the seminiferous tubule. PMID:15379972

  1. Laser capture microdissection in Ectocarpus siliculosus: the pathway to cell-specific transcriptomics in brown algae.

    PubMed

    Saint-Marcoux, Denis; Billoud, Bernard; Langdale, Jane A; Charrier, Bénédicte

    2015-01-01

    Laser capture microdissection (LCM) facilitates the isolation of individual cells from tissue sections, and when combined with RNA amplification techniques, it is an extremely powerful tool for examining genome-wide expression profiles in specific cell-types. LCM has been widely used to address various biological questions in both animal and plant systems, however, no attempt has been made so far to transfer LCM technology to macroalgae. Macroalgae are a collection of widespread eukaryotes living in fresh and marine water. In line with the collective effort to promote molecular investigations of macroalgal biology, here we demonstrate the feasibility of using LCM and cell-specific transcriptomics to study development of the brown alga Ectocarpus siliculosus. We describe a workflow comprising cultivation and fixation of algae on glass slides, laser microdissection, and RNA amplification. To illustrate the effectiveness of the procedure, we show qPCR data and metrics obtained from cell-specific transcriptomes generated from both upright and prostrate filaments of Ectocarpus. PMID:25713580

  2. Laser capture microdissection in Ectocarpus siliculosus: the pathway to cell-specific transcriptomics in brown algae

    PubMed Central

    Saint-Marcoux, Denis; Billoud, Bernard; Langdale, Jane A.; Charrier, Bénédicte

    2015-01-01

    Laser capture microdissection (LCM) facilitates the isolation of individual cells from tissue sections, and when combined with RNA amplification techniques, it is an extremely powerful tool for examining genome-wide expression profiles in specific cell-types. LCM has been widely used to address various biological questions in both animal and plant systems, however, no attempt has been made so far to transfer LCM technology to macroalgae. Macroalgae are a collection of widespread eukaryotes living in fresh and marine water. In line with the collective effort to promote molecular investigations of macroalgal biology, here we demonstrate the feasibility of using LCM and cell-specific transcriptomics to study development of the brown alga Ectocarpus siliculosus. We describe a workflow comprising cultivation and fixation of algae on glass slides, laser microdissection, and RNA amplification. To illustrate the effectiveness of the procedure, we show qPCR data and metrics obtained from cell-specific transcriptomes generated from both upright and prostrate filaments of Ectocarpus. PMID:25713580

  3. Cell-specific blood–brain barrier regulation in health and disease: a focus on hypoxia

    PubMed Central

    Engelhardt, S; Patkar, S; Ogunshola, O O

    2014-01-01

    The blood–brain barrier (BBB) is a complex vascular structure consisting of microvascular endothelial cells that line the vessel wall, astrocyte end-feet, pericytes, as well as the basal lamina. BBB cells act in concert to maintain the characteristic impermeable and low paracellular flux of the brain vascular network, thus ensuring a homeostatic neuronal environment. Alterations in BBB stability that occur during injury have dire consequences on disease progression and it is clear that BBB cell-specific responses, positive or negative, must make a significant contribution to injury outcome. Reduced oxygenation, or hypoxia, is a characteristic of many brain diseases that significantly increases barrier permeability. Recent data suggest that hypoxia-inducible factor (HIF-1), the master regulator of the hypoxic response, probably mediates many hypoxic effects either directly or indirectly via its target genes. This review discusses current knowledge of physiological cell-specific regulation of barrier function, their responses to hypoxia as well as consequences of hypoxic-and HIF-1-mediated mechanisms on barrier integrity during select brain diseases. In the final sections, the potential of current advances in targeting HIF-1 as a therapeutic strategy will be overviewed. PMID:24641185

  4. Spectrometric and voltammetric studies of the interaction between quercetin and bovine serum albumin using warfarin as site marker with the aid of chemometrics

    NASA Astrophysics Data System (ADS)

    Ni, Yongnian; Zhang, Xia; Kokot, Serge

    2009-01-01

    The interaction of quercetin, which is a bioflavonoid, with bovine serum albumin (BSA) was investigated under pseudo-physiological conditions by the application of UV-vis spectrometry, spectrofluorimetry and cyclic voltammetry (CV). These studies indicated a cooperative interaction between the quercetin-BSA complex and warfarin, which produced a ternary complex, quercetin-BSA-warfarin. It was found that both quercetin and warfarin were located in site I. However, the spectra of these three components overlapped and the chemometrics method - multivariate curve resolution-alternating least squares (MCR-ALS) was applied to resolve the spectra. The resolved spectra of quercetin-BSA and warfarin agreed well with their measured spectra, and importantly, the spectrum of the quercetin-BSA-warfarin complex was extracted. These results allowed the rationalization of the behaviour of the overlapping spectra. At lower concentrations ([warfarin] < 1 × 10 -5 mol L -1), most of the site marker reacted with the quercetin-BSA, but free warfarin was present at higher concentrations. Interestingly, the ratio between quercetin-BSA and warfarin was found to be 1:2, suggesting a quercetin-BSA-(warfarin) 2 complex, and the estimated equilibrium constant was 1.4 × 10 11 M -2. The results suggest that at low concentrations, warfarin binds at the high-affinity sites (HAS), while low-affinity binding sites (LAS) are occupied at higher concentrations.

  5. Quercetin reversed lipopolysaccharide-induced inhibition of osteoblast differentiation through the mitogen‑activated protein kinase pathway in MC3T3-E1 cells.

    PubMed

    Wang, Xin-Chun; Zhao, Nzhi-Jun; Guo, Chun; Chen, Jing-Tao; Song, Jin-Ling; Gao, Li

    2014-12-01

    Quercetin, a flavonoid found in onions and other vegetables, has potential inhibitory effects on bone resorption in vivo and in vitro. In our previous study it was identified that quercetin triggered the apoptosis of lipopolysaccharide (LPS)‑induced osteoclasts and inhibited bone resorption. Currently, little information is available detailing the effect of quercetin on osteoblast differentiation and bone formation in bacteria‑induced inflammatory diseases. The present study aimed to investigate the effect of quercetin on osteoblast differentiation in MC3T3‑E1 osteoblasts stimulated with LPS. LPS significantly downregulated the mRNA expression of osteoblast‑related genes in the MC3T3‑E1 cells. By contrast, quercetin significantly restored the LPS‑suppressed mRNA expression of osteoblast‑related genes in a dose‑dependent manner. Quercetin also restored the protein expression of Osterix in MC3T3‑E1 cells suppressed by LPS. Furthermore, quercetin selectively triggered the activation of the mitogen‑activated protein kinase (MAPK) pathway by enhancing the expression of extracellular signal-regulated kinase and reducing the expression of c‑Jun N‑terminal kinase. These data suggest that quercetin reversed the inhibition of osteoblast differentiation induced by LPS through MAPK signaling. These findings suggest that quercetin may be of potential use as a therapeutic agent to restore osteoblast function in bacteria‑induced bone diseases. PMID:25323558

  6. CHNQ, a novel 2-Chloro-1,4-naphthoquinone derivative of quercetin, induces oxidative stress and autophagy both in vitro and in vivo.

    PubMed

    Enayat, Shabnam; Şeyma Ceyhan, M; Taşkoparan, Betül; Stefek, Milan; Banerjee, Sreeparna

    2016-04-15

    Quercetin (Qc) shows strong antitumor effects but has limited clinical application due to poor water solubility and bioavailability. In a screening of novel semi-synthetic derivatives of Qc, 3,7-dihydroxy-2-[4-(2-chloro-1,4-naphthoquinone-3-yloxy)-3-hydroxyphenyl]-5-hydroxychromen-4-one (CHNQ) could ameliorate acetic acid induced acute colitis in vivo more efficiently than Qc. Since inflammation contributes to colorectal cancer (CRC), we have hypothesized that CHNQ may have anti-cancer effects. Using CRC cell lines HCT-116 and HT-29, we report that CHNQ was three-fold more cytotoxic than Qc along with a robust induction of apoptosis. As expected from naphthoquinones such as CHNQ, a strong induction of oxidative stress was observed. This was accompanied by reactive oxygen species (ROS) induced autophagy marked by a dramatic increase in the lipidation of LC3, decreased activation of Akt/PKB, acidic vesicle accumulation and puncta formation in HCT-116 cells treated with CHNQ. Interestingly, an incomplete autophagy was observed in HT-29 cells where CHNQ treatment led to LC3 lipidation, but not the formation of acidic vacuoles. CHNQ-induced cytotoxicity, ROS formation and autophagy were also detected in vivo in Saccharomyces cerevisiae strain RDKY3615 (WinstonS288C background). Overall, we propose that CHNQ can induce cancer cell death through the induction of oxidative stress, and may be examined further as a potential chemotherapeutic drug. PMID:26946942

  7. Quercetin Feeding in Newborn Dairy Calves Cannot Compensate Colostrum Deprivation: Study on Metabolic, Antioxidative and Inflammatory Traits.

    PubMed

    Gruse, Jeannine; Kanitz, Ellen; Weitzel, Joachim M; Tuchscherer, Armin; Stefaniak, Tadeusz; Jawor, Paulina; Wolffram, Siegfried; Hammon, Harald M

    2016-01-01

    Immaturity of the neonatal immune system is causative for high morbidity in calves and colostrum intake is crucial for acquiring passive immunity. Pathogenesis is promoted by reactive oxygen species accumulating at birth if counter-regulation is inadequate. The flavonol quercetin exerts antioxidative and anti-inflammatory effects that may enhance neonatal health. The aim of this work was to study effects of quercetin feeding on metabolic, antioxidative and inflammatory parameters in neonatal calves to investigate whether quercetin could compensate for insufficient colostrum supply. Twenty-eight newborn calves were assigned to two dietary groups fed colostrum or milk-based formula on day 1 and 2 and milk replacer thereafter. From day 2 onwards, 7 calves per diet group were additionally fed quercetin aglycone (50 mg/(kg body weight × day)). Blood samples were taken repeatedly to measure plasma concentrations of flavonols, glucose, lactate, total protein, albumin, urea, non-esterified fatty acids, triglycerides, cholesterol, insulin, glucagon, cortisol, immunoglobulins, fibrinogen, haptoglobin and serum amyloid A. Trolox equivalent antioxidative capacity, ferric reducing ability of plasma, thiobarbituric acid reactive species and F2-isoprostanes were analyzed to evaluate plasma antioxidative status. Expression of tumor necrosis factor, interleukin-1α, interleukin-1β, serum amyloid A, haptoglobin, fibrinogen, C-reactive protein, catalase, glutathione peroxidase and superoxide dismutase mRNA were measured in liver tissue on day 8. Plasma flavonol concentrations were detectable only after quercetin-feeding without differences between colostrum and formula feeding. Plasma glucose, lactate, total protein, immunoglobulins, triglycerides, cholesterol, trolox equivalent antioxidative capacity and thiobarbituric acid reactive species were higher after colostrum feeding. Body temperature, fecal fluidity and plasma concentrations of cortisol and haptoglobin were higher in

  8. Quercetin reduces cyclin D1 activity and induces G1 phase arrest in HepG2 cells

    PubMed Central

    ZHOU, JIN; LI, LU; FANG, LI; XIE, HUA; YAO, WENXIU; ZHOU, XIANG; XIONG, ZHUJUAN; WANG, LI; LI, ZHIXI; LUO, FENG

    2016-01-01

    Quercetin is able to inhibit proliferation of malignant tumor cells; however, the exact mechanism involved in this biological process remains unclear. The current study utilized a quantitative proteomic analysis to explore the antitumor mechanisms of quercetin. The leucine of HepG2 cells treated with quercetin was labeled as d3 by stable isotope labeling by amino acids in cell culture (SILAC). The isotope peaks of control HepG2 cells were compared with the d3-labeled HepG2 cells by mass spectrometry (MS) to identify significantly altered proteins. Reverse transcription-polymerase chain reaction (RT-PCR) and western blot analyses were subsequently employed to verify the results of the MS analysis. A flow cytometry assay was designed to observe the influence of various quercetin treatment concentrations on the cell cycle distribution of HepG2 cells. The results indicated that quercetin is able to substantially inhibit proliferation of HepG2 cells and induce an obvious morphological alteration of cells. According to the MS results, the 70 credibly-changed proteins that were identified may play important roles in multiple cellular processes, including protein synthesis, signaling, cytoskeletal processes and metabolism. Among these functional proteins, the expression of cyclin D1 (CCND1) was found to be significantly decreased. RT-PCR and western blot analyses verified the SILAC-MS results of decreased CCND1 expression. In summary, flow cytometry revealed that quercetin is able to induce G1 phase arrest in HepG2 cells. Based on the aforementioned observations, it is suggested that quercetin exerts antitumor activity in HepG2 cells through multiple pathways, including interfering with CCND1 gene expression to disrupt the cell cycle and proliferation of HepG2 cells. In the future, we aim to explore this effect in vivo. PMID:27347174

  9. Single-dose oral quercetin improves redox status but does not affect heat shock response in mice.

    PubMed

    Chen, Yifan; Islam, Aminul; Abraham, Preetha; Deuster, Patricia

    2014-07-01

    Inflammation and oxidative stress are considered as likely contributors to heat injury. However, their roles in regulating the heat shock response in vivo remain unclear. We tested the hypothesis that acute quercetin treatment would improve redox status and reduce heat shock responses in mice. Mice underwent two heat tests before and after single oral administration of either quercetin (15 mg/kg) or vehicle. We measured physiologic and biochemical responses in mice during and 18 to 22 hours after heat tests, respectively. There were no significant differences in core temperature, heart rate, or blood pressure between quercetin and vehicle groups during heat exposure. Mice with relatively severe hyperthermia during the pretreatment heat test showed a significant trend toward a lower peak core temperature during the heat test after quercetin treatment. Compared with mice not exposed to heat, quercetin-treated mice had significantly lower interleukin 6 (P < .01) and higher superoxide dismutase levels (P < .01), whereas vehicle-treated mice had significantly lower total glutathione and higher 8-isoprostane levels in the circulation after heat exposure. Heat exposure significantly elevated heat shock proteins (HSPs) 72 and 90 and heat shock factor 1 levels in mouse liver, heart, and skeletal muscles, but no significant differences in tissue HSPs and heat shock factor 1 were found between quercetin- and vehicle-treated mice. These results suggest that a single moderate dose of quercetin is sufficient to alter redox status but not heat stress response in mice. Acute adaptations of peripheral tissues to heat stress may not be mediated by systemic inflammatory and redox state in vivo. PMID:25150121

  10. Quercetin Feeding in Newborn Dairy Calves Cannot Compensate Colostrum Deprivation: Study on Metabolic, Antioxidative and Inflammatory Traits

    PubMed Central

    Gruse, Jeannine; Kanitz, Ellen; Weitzel, Joachim M.; Tuchscherer, Armin; Stefaniak, Tadeusz; Jawor, Paulina; Wolffram, Siegfried; Hammon, Harald M.

    2016-01-01

    Immaturity of the neonatal immune system is causative for high morbidity in calves and colostrum intake is crucial for acquiring passive immunity. Pathogenesis is promoted by reactive oxygen species accumulating at birth if counter-regulation is inadequate. The flavonol quercetin exerts antioxidative and anti-inflammatory effects that may enhance neonatal health. The aim of this work was to study effects of quercetin feeding on metabolic, antioxidative and inflammatory parameters in neonatal calves to investigate whether quercetin could compensate for insufficient colostrum supply. Twenty-eight newborn calves were assigned to two dietary groups fed colostrum or milk-based formula on day 1 and 2 and milk replacer thereafter. From day 2 onwards, 7 calves per diet group were additionally fed quercetin aglycone (50 mg/(kg body weight × day)). Blood samples were taken repeatedly to measure plasma concentrations of flavonols, glucose, lactate, total protein, albumin, urea, non-esterified fatty acids, triglycerides, cholesterol, insulin, glucagon, cortisol, immunoglobulins, fibrinogen, haptoglobin and serum amyloid A. Trolox equivalent antioxidative capacity, ferric reducing ability of plasma, thiobarbituric acid reactive species and F2-isoprostanes were analyzed to evaluate plasma antioxidative status. Expression of tumor necrosis factor, interleukin-1α, interleukin-1β, serum amyloid A, haptoglobin, fibrinogen, C-reactive protein, catalase, glutathione peroxidase and superoxide dismutase mRNA were measured in liver tissue on day 8. Plasma flavonol concentrations were detectable only after quercetin-feeding without differences between colostrum and formula feeding. Plasma glucose, lactate, total protein, immunoglobulins, triglycerides, cholesterol, trolox equivalent antioxidative capacity and thiobarbituric acid reactive species were higher after colostrum feeding. Body temperature, fecal fluidity and plasma concentrations of cortisol and haptoglobin were higher in

  11. Quercetin prevents ethanol-induced iron overload by regulating hepcidin through the BMP6/SMAD4 signaling pathway.

    PubMed

    Tang, Yuhan; Li, Yanyan; Yu, Haiyan; Gao, Chao; Liu, Liang; Chen, Shaodan; Xing, Mingyou; Liu, Liegang; Yao, Ping

    2014-06-01

    Emerging evidence has demonstrated that chronic ethanol exposure induces iron overload, enhancing ethanol-mediated liver damage. The purpose of this study was to explore the effects of the naturally occurring compound quercetin on ethanol-induced iron overload and liver damage, focusing on the signaling pathway of the iron regulatory hormone hepcidin. Adult male C57BL/6J mice were pair-fed with isocaloric-Lieber De Carli diets containing ethanol (accounting for 30% of total calories) and/or carbonyl iron (0.2%) and treated with quecertin (100 mg/kg body weight) for 15 weeks. Mouse primary hepatocytes were incubated with ethanol (100 mM) and quercetin (100 μM) for 24 h. Mice exposed to either ethanol or iron presented significant fatty infiltration and iron deposition in the liver; these symptoms were exacerbated in mice cotreated with ethanol and iron. Quercetin attenuated the abnormity induced by ethanol and/or iron. Ethanol suppressed BMP6 and intranuclear SMAD4 as well as decreased hepcidin expression. These effects were partially alleviated by quercetin supplementation in mice and hepatocytes. Importantly, ethanol caused suppression of SMAD4 binding to the HAMP promoter and of hepcidin messenger RNA expression. These effects were exacerbated by anti-BMP6 antibody and partially alleviated by quercetin or human recombinant BMP6 in cultured hepatocytes. In contrast, co-treatment with iron and ethanol, especially exposure of iron alone, activated BMP6/SMAD4 pathway and up-regulated hepcidin expression, which was also normalized by quercetin in vivo. Quercetin prevented ethanol-induced hepatic iron overload different from what carbonyl iron diet elicited in the mechanism, by regulating hepcidin expression via the BMP6/SMAD4 signaling pathway. PMID:24746831

  12. Quercetin protects against aluminium induced oxidative stress and promotes mitochondrial biogenesis via activation of the PGC-1α signaling pathway.

    PubMed

    Sharma, Deep Raj; Sunkaria, Aditya; Wani, Willayat Yousuf; Sharma, Reeta Kumari; Verma, Deepika; Priyanka, Kumari; Bal, Amanjit; Gill, Kiran Dip

    2015-12-01

    The present investigation was carried out to elucidate a possible molecular mechanism related to the protective effect of quercetin administration against aluminium-induced oxidative stress on various mitochondrial respiratory complex subunits with special emphasis on the role of PGC-1α and its downstream targets, i.e. NRF-1, NRF-2 and Tfam in mitochondrial biogenesis. Aluminium lactate (10mg/kg b.wt./day) was administered intragastrically to rats, which were pre-treated with quercetin 6h before aluminium (10mg/kg b.wt./day, intragastrically) for 12 weeks. We found a decrease in ROS levels, mitochondrial DNA oxidation and citrate synthase activity in the hippocampus (HC) and corpus striatum (CS) regions of rat brain treated with quercetin. Besides this an increase in the mRNA levels of the mitochondrial encoded subunits - ND1, ND2, ND3, Cyt b, COX1, COX3 and ATPase6 along with increased expression of nuclear encoded subunits COX4, COX5A and COX5B of electron transport chain (ETC). In quercetin treated group an increase in the mitochondrial DNA copy number and mitochondrial content in both the regions of rat brain was observed. The PGC-1α was up regulated in quercetin treated rats along with NRF-1, NRF-2 and Tfam, which act downstream from PGC-1α. Electron microscopy results revealed a significant decrease in the mitochondrial cross-section area, mitochondrial perimeter length and increase in mitochondrial number in case of quercetin treated rats as compared to aluminium treated ones. Therefore it seems quercetin increases mitochondrial biogenesis and makes it an almost ideal flavanoid to control or limit the damage that has been associated with the defective mitochondrial function seen in many neurodegenerative diseases. PMID:26493151

  13. [Cancer].

    PubMed

    de la Peña-López, Roberto; Remolina-Bonilla, Yuly Andrea

    2016-09-01

    Cancer is a group of diseases which represents a significant public health problem in Mexico and worldwide. In Mexico neoplasms are the second leading cause of death. An increased morbidity and mortality are expected in the next decades. Several preventable risk factors for cancer development have been identified, the most relevant including tobacco use, which accounts for 30% of the cancer cases; and obesity, associated to another 30%. These factors, in turn, are related to sedentarism, alcohol abuse and imbalanced diets. Some agents are well knokn to cause cancer such as ionizing radiation, viruses such as the papilloma virus (HPV) and hepatitis virus (B and C), and more recently environmental pollution exposure and red meat consumption have been pointed out as carcinogens by the International Agency for Research in Cancer (IARC). The scientific evidence currently available is insufficient to consider milk either as a risk factor or protective factor against different types of cancer. PMID:27603890

  14. Irreversibility of T-Cell Specification: Insights from Computational Modelling of a Minimal Network Architecture

    PubMed Central

    Manesso, Erica; Kueh, Hao Yuan; Freedman, George; Rothenberg, Ellen V.

    2016-01-01

    Background/Objectives A cascade of gene activations under the control of Notch signalling is required during T-cell specification, when T-cell precursors gradually lose the potential to undertake other fates and become fully committed to the T-cell lineage. We elucidate how the gene/protein dynamics for a core transcriptional module governs this important process by computational means. Methods We first assembled existing knowledge about transcription factors known to be important for T-cell specification to form a minimal core module consisting of TCF-1, GATA-3, BCL11B, and PU.1 aiming at dynamical modeling. Model architecture was based on published experimental measurements of the effects on each factor when each of the others is perturbed. While several studies provided gene expression measurements at different stages of T-cell development, pure time series are not available, thus precluding a straightforward study of the dynamical interactions among these genes. We therefore translate stage dependent data into time series. A feed-forward motif with multiple positive feed-backs can account for the observed delay between BCL11B versus TCF-1 and GATA-3 activation by Notch signalling. With a novel computational approach, all 32 possible interactions among Notch signalling, TCF-1, and GATA-3 are explored by translating combinatorial logic expressions into differential equations for BCL11B production rate. Results Our analysis reveals that only 3 of 32 possible configurations, where GATA-3 works as a dimer, are able to explain not only the time delay, but very importantly, also give rise to irreversibility. The winning models explain the data within the 95% confidence region and are consistent with regard to decay rates. Conclusions This first generation model for early T-cell specification has relatively few players. Yet it explains the gradual transition into a committed state with no return. Encoding logics in a rate equation setting allows determination of

  15. The Effect of Quercetin on the Osteogenesic Differentiation and Angiogenic Factor Expression of Bone Marrow-Derived Mesenchymal Stem Cells

    PubMed Central

    Zhou, Yuning; Wu, Yuqiong; Jiang, Xinquan; Zhang, Xiuli; Xia, Lunguo; Lin, Kaili; Xu, Yuanjin

    2015-01-01

    Bone marrow-derived mesenchymal stem cells (BMSCs) are widely used in regenerative medicine in light of their ability to differentiate along the chondrogenic and osteogenic lineages. As a type of traditional Chinese medicine, quercetin has been preliminarily reported to promote osteogenic differentiation in osteoblasts. In the present study, the effects of quercetin on the proliferation, viability, cellular morphology, osteogenic differentiation and angiogenic factor secretion of rat BMSCs (rBMSCs) were examined by MTT assay, fluorescence activated cell sorter (FACS) analysis, real-time quantitative PCR (RT-PCR) analysis, alkaline phosphatase (ALP) activity and calcium deposition assays, and Enzyme-linked immunosorbent assay (ELISA). Moreover, whether mitogen-activated protein kinase (MAPK) signaling pathways were involved in these processes was also explored. The results showed that quercetin significantly enhanced the cell proliferation, osteogenic differentiation and angiogenic factor secretion of rBMSCs in a dose-dependent manner, with a concentration of 2 μM achieving the greatest stimulatory effect. Moreover, the activation of the extracellular signal-regulated protein kinases (ERK) and p38 pathways was observed in quercetin-treated rBMSCs. Furthermore, these induction effects could be repressed by either the ERK inhibitor PD98059 or the p38 inhibitor SB202190, respectively. These data indicated that quercetin could promote the proliferation, osteogenic differentiation and angiogenic factor secretion of rBMSCs in vitro, partially through the ERK and p38 signaling pathways. PMID:26053266

  16. Minor effects of the citrus flavonoids naringin, naringenin and quercetin, on the pharmacokinetics of doxorubicin in rats.

    PubMed

    Park, Hyun-seo; Oh, Ju-Hee; Lee, Joo hyun; Lee, Young-Joo

    2011-06-01

    We investigated the effects of naringin, naringenin and quercetin on the pharmacokinetics of doxorubicin in rats. These Citrus flavonoids are known as P-glycoprotein (P-gp) inhibitors and thus suspected to interact with doxorubicin, as shown by in vitro cell studies. Plasma concentrations, tissue distribution, and the urinary and biliary excretion of doxorubicin after intravenous infusion were investigated in rats followed by oral administration of Citrus flavonoids. To evaluate the impact of the biotransformation of Citrus flavonoids on the P-gp inhibition, the inhibitory effects of quercetin and its metabolite on P-gp were compared using ex vivo analysis. Contrary to previous in vitro results, the plasma concentration, biliary and urinary clearance, and tissue distribution of doxorubicin were not altered by pre-treatment with naringin and naringenin. Biliary clearance and urinary clearance were slightly decreased by quercetin, but there was no statistical difference. The minor effects of these flavonoids may relate to their low systemic concentration, due to the biotransformation in vivo situation. S9 stability assay and calcein accumulation assay showed that quercetin was a metabolically unstable compound, and the inhibitory effect of its metabolites on P-gp was negligible. In conclusion, naringin, naringenin and quercetin did not affect the in vivo pharmacokinetics of intravenously administered doxorubicin. PMID:21699081

  17. Protective effects of kolaviron and quercetin on cadmium-induced testicular damage and endocrine pathology in rats.

    PubMed

    Farombi, E O; Adedara, I A; Akinrinde, S A; Ojo, O O; Eboh, A S

    2012-08-01

    This study evaluated the effects of kolaviron, a biflavonoid from Garcinia kola seed, and quercetin on cadmium-induced reproductive toxicity in rats. Adult male rats were administered with either cadmium (15 mg kg(-1)) alone or in combination with kolaviron (200 mg kg(-1)) or quercetin (10 mg kg(-1)) daily for 5 days. Cadmium-treated rats showed (P < 0.05) decrease in the body weight gain, testis and epididymis weights. However, upon co-administration of kolaviron or quercetin, these changes were significantly reversed in cadmium-treated rats. Also, administration of kolaviron or quercetin significantly prevented cadmium-mediated decrease in sperm motility and epididymal sperm concentration and reversed the increased level of sperm abnormality to near control. In testes and sperm, cadmium treatment resulted in significant decrease in the activities of superoxide dismutase, catalase and glutathione peroxidase, whereas it increased glutathione S-transferase activity as well as hydrogen peroxide and malondialdehyde levels. While plasma levels of triiodothyronine and tetraiodothyronine remained unaffected, the levels of testosterone, luteinising hormone and follicle stimulating hormone were decreased in cadmium-treated rats. Cadmium treatment caused mild congestion of interstitial vessels and oedema in the testes. Taken together, kolaviron and quercetin inhibited the adverse effects of cadmium on the antioxidant enzymes, markers of oxidative stress, endocrine and testicular structure in rats. PMID:22356231

  18. The effect of quercetin on oxidative DNA damage and myelosuppression induced by etoposide in bone marrow cells of rats.

    PubMed

    Papież, Monika A

    2014-01-01

    There is increasing evidence for the existence of an association between the presence of etoposide phenoxyl radicals and the development of treatment-related acute myeloid leukemia (t-AML), which occurs in a few percent of patients treated with this chemotherapeutic agent. The most common side effect caused by etoposide is myelosuppression, which limits the use of this effective drug. The goal of the study was to investigate the influence of antioxidant querectin on myelosuppression and oxidative DNA damage caused by etoposide. The influence of quercetin and/or etoposide on oxidative DNA damage was investigated in LT-12 cell line and bone marrow cells of rats via comet assay. The effect of quercetin on myelosuppression induced by etoposide was invetsigated by cytological analysis of bone marrow smears stained with May-Grünwald-Giemsa stain. Etoposide caused a significant increase in oxidative DNA damage in bone marrow cells and LT-12 cell line in comparison to the appropriate controls. Quercetin significantly reduced the oxidative DNA damage caused by etoposide both in vitro and in vivo. Quercetin also significantly protected against a decrease in the percentage of myeloid precursors and erythroid nucleated cells caused by etoposide administration in comparison to the group treated with etoposide alone. The results of the study indicate that quercetin could be considered a protectively acting compound in bone marrow cells during etoposide therapy. PMID:24644549

  19. The Effect of Quercetin on the Osteogenesic Differentiation and Angiogenic Factor Expression of Bone Marrow-Derived Mesenchymal Stem Cells.

    PubMed

    Zhou, Yuning; Wu, Yuqiong; Jiang, Xinquan; Zhang, Xiuli; Xia, Lunguo; Lin, Kaili; Xu, Yuanjin

    2015-01-01

    Bone marrow-derived mesenchymal stem cells (BMSCs) are widely used in regenerative medicine in light of their ability to differentiate along the chondrogenic and osteogenic lineages. As a type of traditional Chinese medicine, quercetin has been preliminarily reported to promote osteogenic differentiation in osteoblasts. In the present study, the effects of quercetin on the proliferation, viability, cellular morphology, osteogenic differentiation and angiogenic factor secretion of rat BMSCs (rBMSCs) were examined by MTT assay, fluorescence activated cell sorter (FACS) analysis, real-time quantitative PCR (RT-PCR) analysis, alkaline phosphatase (ALP) activity and calcium deposition assays, and Enzyme-linked immunosorbent assay (ELISA). Moreover, whether mitogen-activated protein kinase (MAPK) signaling pathways were involved in these processes was also explored. The results showed that quercetin significantly enhanced the cell proliferation, osteogenic differentiation and angiogenic factor secretion of rBMSCs in a dose-dependent manner, with a concentration of 2 μM achieving the greatest stimulatory effect. Moreover, the activation of the extracellular signal-regulated protein kinases (ERK) and p38 pathways was observed in quercetin-treated rBMSCs. Furthermore, these induction effects could be repressed by either the ERK inhibitor PD98059 or the p38 inhibitor SB202190, respectively. These data indicated that quercetin could promote the proliferation, osteogenic differentiation and angiogenic factor secretion of rBMSCs in vitro, partially through the ERK and p38 signaling pathways. PMID:26053266

  20. Effects of quercetin on predator stress-related hematological and behavioral alterations in pregnant rats and their offspring.

    PubMed

    Toumi, Mohamed L; Merzoug, Sameha; Tahraoui, Abdelkrim

    2016-06-01

    This study aims at investigating the effect of a psychogenic stress during gestation on the behaviour and haematological indices in dams as well as on the neonatal haematological status and periadolescent behaviour in their offspring. Moreover, the ability of quercetin, a natural flavonoid, to prevent the stress-induced changes was estimated. Pregnant Wistar rats were pretreated with quercetin before the exposure to a predator stress on gestational day 19. Post-stress maternal anxiety-like behaviour was assessed with a concomitant haematological analysis. In the offspring, haematological analysis and behavioural testing were performed during the postnatal stage. Our results revealed that predator stress causes an anxiety-like behaviour in dams along with a decrease in erythrocytes, a microcytosis, and a thrombocytosis. Prenatally stressed neonates manifested microcytosis and thrombocytosis with a significant polycythemia. Signs of motor hyperactivity, anxiety-like behaviour, and memory dysfunction were detected at periadolescence. Quercetin pretreatment alleviated the stress-induced behavioural and haematological impairments in dams but failed to attenuate the haematological changes in neonates. A sex-dependent effect of quercetin on behaviour was found at periadolescence. Our findings suggest that, besides a beneficial effect on haematological and behavioural anomalies in traumatized dams, quercetin may lastingly modulate the behaviour of their progeny. PMID:27240984

  1. Acetonic and Methanolic Extracts of Heterotheca inuloides, and Quercetin, Decrease CCl4-Oxidative Stress in Several Rat Tissues

    PubMed Central

    Coballase-Urrutia, Elvia; Pedraza-Chaverri, José; Cárdenas-Rodríguez, Noemí; Huerta-Gertrudis, Bernardino; García-Cruz, Mercedes Edna; Montesinos-Correa, Hortencia; Sánchez-González, Dolores Javier; Camacho-Carranza, Rafael; Espinosa-Aguirre, Jesús Javier

    2013-01-01

    The present study was designed to test the hypothesis that the acetonic and methanolic extracts of H. inuloides prevent carbon tetrachloride-(CCl4) induced oxidative stress in vital tissues. Pretreatment with both H. inuloides extracts or quercetin attenuated the increase in serum activity of alkaline phosphatase (ALP), total bilirubin (BB), creatinine (CRE), and creatine kinase (CK), and impeded the decrease of γ-globulin (γ-GLOB) and albumin (ALB) observed in CCl4-induced tissue injury. The protective effect was confirmed by histological analysis with hematoxylin-eosin and periodic acid/Schiff's reagent. Level of lipid peroxidation was higher in the organs of rats exposed to CCl4 than in those of the animals treated with Heterohteca extracts or quercetin, and these showed levels similar to the untreated group. Pretreatment of animals with either of the extracts or quercetin also prevented the increase of 4-hydroxynonenal and 3-nitrotyrosine. Pretreatment with the plant extracts or quercetin attenuated CCl4 toxic effects on the activity of several antioxidant enzymes. The present results strongly suggest that the chemopreventive effect of the extracts used and quercetin, against CCl4 toxicity, is associated with their antioxidant properties and corroborated previous results obtained in liver tissue. PMID:23365610

  2. Quercetin Inhibits Peripheral and Spinal Cord Nociceptive Mechanisms to Reduce Intense Acute Swimming-Induced Muscle Pain in Mice.

    PubMed

    Borghi, Sergio M; Pinho-Ribeiro, Felipe A; Fattori, Victor; Bussmann, Allan J C; Vignoli, Josiane A; Camilios-Neto, Doumit; Casagrande, Rubia; Verri, Waldiceu A

    2016-01-01

    The present study aimed to evaluate the effects of the flavonoid quercetin (3,3´,4´,5,7-pentahydroxyflavone) in a mice model of intense acute swimming-induced muscle pain, which resembles delayed onset muscle soreness. Quercetin intraperitoneal (i.p.) treatment dose-dependently reduced muscle mechanical hyperalgesia. Quercetin inhibited myeloperoxidase (MPO) and N-acetyl-β-D- glucosaminidase (NAG) activities, cytokine production, oxidative stress, cyclooxygenase-2 (COX-2) and gp91phox mRNA expression and muscle injury (creatinine kinase [CK] blood levels and myoblast determination protein [MyoD] mRNA expression) as well as inhibited NFκB activation and induced Nrf2 and HO-1 mRNA expression in the soleus muscle. Beyond inhibiting those peripheral effects, quercetin also inhibited spinal cord cytokine production, oxidative stress and glial cells activation (glial fibrillary acidic protein [GFAP] and ionized calcium-binding adapter molecule 1 [Iba-1] mRNA expression). Concluding, the present data demonstrate that quercetin is a potential molecule for the treatment of muscle pain conditions related to unaccustomed exercise. PMID:27583449

  3. Evaluating bacterial activity from cell-specific ribosomal RNA content measured with oligonucleotide probes

    SciTech Connect

    Kemp, P.F.; Lee, S.; LaRoche, J.

    1992-10-01

    We describe a procedure for measuring the cell-specific quantity of ribosomal RNA (rRNA) and DNA in order to evaluate the frequency distribution of activity among cells. The procedure is inherently quantitative, does not require sample incubation and potentially can be taxon-specific. Fluorescently-labelled oligonucleotide probes are hybridized to the complementary 16S rRNA sequences in preserved, intact cells. The resulting cell fluorescence is proportional to cellular rRNA content and can be measured with a microscope-mounted photometer system, by image analysis, or by flow cytometry. Similarly, DNA content is measured as fluorescence of cells stained with the DNA specific fluorochrome DAPI. These are either prepared as separate samples for purposes of enumeration and DNA measurements, or are dual-labelled cells which are also hybridized with oligonucleotide probes.

  4. Evaluating bacterial activity from cell-specific ribosomal RNA content measured with oligonucleotide probes

    SciTech Connect

    Kemp, P.F.; Lee, S.; LaRoche, J.

    1992-01-01

    We describe a procedure for measuring the cell-specific quantity of ribosomal RNA (rRNA) and DNA in order to evaluate the frequency distribution of activity among cells. The procedure is inherently quantitative, does not require sample incubation and potentially can be taxon-specific. Fluorescently-labelled oligonucleotide probes are hybridized to the complementary 16S rRNA sequences in preserved, intact cells. The resulting cell fluorescence is proportional to cellular rRNA content and can be measured with a microscope-mounted photometer system, by image analysis, or by flow cytometry. Similarly, DNA content is measured as fluorescence of cells stained with the DNA specific fluorochrome DAPI. These are either prepared as separate samples for purposes of enumeration and DNA measurements, or are dual-labelled cells which are also hybridized with oligonucleotide probes.

  5. Cloning of the novel human myeloid-cell-specific C/EBP-epsilon transcription factor.

    PubMed Central

    Chumakov, A M; Grillier, I; Chumakova, E; Chih, D; Slater, J; Koeffler, H P

    1997-01-01

    Chicken NF-M transcription factor, in cooperation with either c-Myb or v-Myb, is active in the combinatorial activation of myeloid-cell-specific genes in heterologous cell types, such as embryonic fibroblasts. In humans, similar effects were observed with homologous members of the CCAAT/enhancer-binding protein (C/EBP) family of transcriptional regulators, especially the human homolog of chicken NF-M, C/EBP-beta (NF-IL6). However, the NF-IL6 gene is expressed in a variety of nonmyeloid cell types and is strongly inducible in response to inflammatory stimuli, making it an unlikely candidate to have an exclusive role as a combinatorial differentiation switch during myelopoiesis in human cells. By using a reverse transcription-PCR-based approach and a set of primers specific for the DNA-binding domains of highly homologous members of the C/EBP family of transcriptional regulators, we have cloned a novel human gene encoding a member of the C/EBP gene family, identified as the human homolog of CRP1, C/EBP-epsilon. A 1.2-kb cDNA encoding full-length human C/EBP-epsilon was cloned from a promyelocyte-late myeloblast-derived lambda gt11 library. Molecular analysis of the cDNA and genomic clones indicated the presence of two exons encoding a protein with an apparent molecular mass of 32 kDa and a pI of 9.5. Primer extension analysis of C/EBP-epsilon mRNA detected a single major transcription start site approximately 200 bp upstream of the start codon. The putative promoter area is similar to those of several other myeloid-cell-specific genes in that it contains no TATAAA box but has a number of purine-rich stretches with multiple sites for the factors of the Ets family of transcriptional regulators. Northern blot analyses indicated a highly restricted mRNA expression pattern, with the strongest expression occurring in promyelocyte and late-myeloblast-like cell lines. Western blot and immunoprecipitation studies using rabbit anti-C/EBP-epsilon antibodies raised against the N

  6. Male germ cell-specific expression of a novel Patched-domain containing gene Ptchd3

    SciTech Connect

    Fan Jun; Akabane, Hiroto; Zheng Xuehai; Zhou Xuan; Zhang Li; Liu Qiang; Zhang Yonglian; Yang Jing; Zhu Guozhang

    2007-11-23

    The Hedgehog (Hh) signaling pathway plays an important role in various biological processes, including pattern formation, cell fate determination, proliferation, and differentiation. Hh function is mediated through its membrane receptor Patched. Herein, we have characterized a novel Patched-domain containing gene Ptchd3 in mouse. Messenger RNA of Ptchd3 was exclusively detected in the testis, and existed in two isoforms Ptchd3a and Ptchd3b. The expression of these two mRNA isoforms was shown to be developmentally regulated in testes, and specifically found in male germ cells. Further analysis revealed that the Ptchd3 protein was located on the midpiece of mouse, rat and human sperm. Collectively, these results indicate that Ptchd3 is a novel male germ cell-specific gene and may be involved in the Hh signaling to regulate sperm development and/or sperm function.

  7. Foxi3 Deficiency Compromises Hair Follicle Stem Cell Specification and Activation.

    PubMed

    Shirokova, Vera; Biggs, Leah C; Jussila, Maria; Ohyama, Takahiro; Groves, Andrew K; Mikkola, Marja L

    2016-07-01

    The hair follicle is an ideal system to study stem cell specification and homeostasis due to its well characterized morphogenesis and stereotypic cycles of stem cell activation upon each hair cycle to produce a new hair shaft. The adult hair follicle stem cell niche consists of two distinct populations, the bulge and the more activation-prone secondary hair germ (HG). Hair follicle stem cells are set aside during early stages of morphogenesis. This process is known to depend on the Sox9 transcription factor, but otherwise the establishment of the hair follicle stem cell niche is poorly understood. Here, we show that that mutation of Foxi3, a Forkhead family transcription factor mutated in several hairless dog breeds, compromises stem cell specification. Further, loss of Foxi3 impedes hair follicle downgrowth and progression of the hair cycle. Genome-wide profiling revealed a number of downstream effectors of Foxi3 including transcription factors with a recognized function in hair follicle stem cells such as Lhx2, Runx1, and Nfatc1, suggesting that the Foxi3 mutant phenotype results from simultaneous downregulation of several stem cell signature genes. We show that Foxi3 displays a highly dynamic expression pattern during hair morphogenesis and cycling, and identify Foxi3 as a novel secondary HG marker. Absence of Foxi3 results in poor hair regeneration upon hair plucking, and a sparse fur phenotype in unperturbed mice that exacerbates with age, caused by impaired secondary HG activation leading to progressive depletion of stem cells. Thus, Foxi3 regulates multiple aspects of hair follicle development and homeostasis. Stem Cells 2016;34:1896-1908. PMID:26992132

  8. Identification of cell-specific targets of sumoylation during mouse spermatogenesis

    PubMed Central

    Xiao, Yuxuan; Pollack, Daniel; Andrusier, Miriam; Levy, Avi; Callaway, Myrasol; Nieves, Edward; Reddi, Prabhakara; Vigodner, Margarita

    2015-01-01

    Recent findings suggest diverse and potentially multiple roles of SUMO in testicular function and spermatogenesis. However, SUMO targets remain uncharacterized in the testis due to the complex multicellular nature of testicular tissue, the inability to maintain and manipulate spermatogenesis in vitro, and the technical challenges involved in identifying low-abundance endogenous SUMO targets. In this study, we performed cell-specific identification of sumoylated proteins using concentrated cell lysates prepared with de-sumoylation inhibitors from freshly purified spermatocytes and spermatids. One-hundred and twenty proteins were uniquely identified in the spermatocyte and/or spermatid fractions. The identified proteins are involved in the regulation of transcription, stress response, microRNA biogenesis, regulation of major enzymatic pathways, nuclear-cytoplasmic transport, cell cycle control, acrosome biogenesis, and other processes. Several proteins with important roles during spermatogenesis were chosen for further characterization by co-immunoprecipitation, co-localization and in-vitro sumoylation studies. GPS-SUMO software was used to identify consensus and non-consensus sumoylation sites within the amino acid sequences of the proteins. The analyses confirmed the cell-specific sumoylation and/or SUMO interaction of several novel, previously uncharacterized SUMO targets such as CDK1, RNAP II, CDC5, MILI, DDX4, TDP-43 and STK31. Furthermore, several proteins that were previously identified as SUMO targets in somatic cells (e.g., KAP1, MDC1) were identified as SUMO targets in germ cells. Many of these proteins have a unique role in spermatogenesis and during meiotic progression. This research opens a novel avenue for further studies of SUMO at the level of individual targets. PMID:26701181

  9. Germ Cell-Specific Excision of loxP-Flanked Transgenes in Rainbow Trout Oncorhynchus mykiss.

    PubMed

    Katayama, Naoto; Kume, Sachi; Hattori-Ihara, Shoko; Sadaie, Sakiko; Hayashi, Makoto; Yoshizaki, Goro

    2016-04-01

    Cre/loxP-mediated DNA excision in germ cell lineages could contribute substantially to the study of germ cell biology in salmonids, which are emerging as a model species in this field. However, a cell type-specific Cre/loxPsystem has not been successfully developed for any salmonid species. Therefore, we examined the feasibility of Cre/loxP-mediated, germ cell-specific gene excision and transgene activation in rainbow trout. Double-transgenic (wTg) progeny were obtained by mating a transgenic male carryingcrewith a transgenic female carrying thehsc-LRLGgene;crewas driven by rainbow troutvasaregulatory regions and thehsc-LRLGgene was made up of the rainbow troutheat-shock-cognate71promoter, theDsRedgene flanked by twoloxPsites, and theEgfpgene. PCR analysis, fluorescence imaging, and histological analysis revealed that excision of theloxP-flanked sequence and activation ofEgfpoccurred only in germ cells of wTg fish. However, progeny tests revealed that the excision efficiency ofloxP-flanked sequence in germ cells was low (≤3.27%). In contrast, the other wTg fish derived from two differentcre-transgenic males frequently excised theloxP-flanked sequence in germ cells (≤89.25%). Thus, we showed for the first time successful germ cell-specific transgene manipulation via the Cre/loxPsystem in rainbow trout. We anticipate that this technology will be suitable for studies of cell function through cell targeting, cell-linage tracing, and generating cell type-specific conditional gene knockouts and separately for developing sterile rainbow trout in aquaculture. PMID:26911430

  10. Dual drug loaded chitosan nanoparticles-sugar--coated arsenal against pancreatic cancer.

    PubMed

    David, Karolyn Infanta; Jaidev, Leela Raghav; Sethuraman, Swaminathan; Krishnan, Uma Maheswari

    2015-11-01

    Pancreatic cancer is an aggressive form of cancer with poor survival rates. The increased mortality due to pancreatic cancer arises due to many factors such as development of multidrug resistance, presence of cancer stem cells, development of a stromal barrier and a hypoxic environment due to hypo-perfusion. The present study aims to develop a nanocarrier for a combination of drugs that can address these multiple issues. Quercetin and 5-fluorouracil were loaded in chitosan nanoparticles, individually as well as in combination. The nanoparticles were characterized for morphology, size, zeta potential, percentage encapsulation of drugs as well as their release profiles in different media. The dual drug-loaded carrier exhibited good entrapment efficiency (quercetin 95% and 5-fluorouracil 75%) with chitosan: quercetin: 5-fluorouracil in the ratio 3:1:2. The release profiles suggest that 5-fluorouracil preferentially localized in the periphery while quercetin was located towards the core of chitosan nanoparticles. Both drugs exhibited considerable association with the chitosan matrix. The dual drug-loaded carrier system exhibited significant toxicity towards pancreatic cancer cells both in the 2D as well as in the 3D cultures. We believe that the results from these studies can open up interesting options in the treatment of pancreatic cancer. PMID:26340358

  11. HPLC Method for Simultaneous Quantitative Detection of Quercetin and Curcuminoids in Traditional Chinese Medicines

    PubMed Central

    Ang, Lee Fung; Yam, Mun Fei; Fung, Yvonne Tan Tze; Kiang, Peh Kok; Darwin, Yusrida

    2014-01-01

    Objectives: Quercetin and curcuminoids are important bioactive compounds found in many herbs. Previously reported high performance liquid chromatography ultraviolet (HPLC-UV) methods for the detection of quercetin and curcuminoids have several disadvantages, including unsatisfactory separation times and lack of validation according the standard guidelines of the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use. Methods: A rapid, specific, reversed phase, HPLC-UV method with an isocratic elution of acetonitrile and 2% v/v acetic acid (40% : 60% v/v) (pH 2.6) at a flow rate of 1.3 mL/minutes, a column temperature of 35°C, and ultraviolet (UV) detection at 370 nm was developed. The method was validated and applied to the quantification of different types of market available Chinese medicine extracts, pills and tablets. Results: The method allowed simultaneous determination of quercetin, bisdemethoxycurcumin, demethoxycurcumin and curcumin in the concentration ranges of 0.00488 ─ 200 μg/mL, 0.625 ─ 320 μg/mL, 0.07813 ─ 320 μg/mL and 0.03906 ─ 320 μg/mL, respectively. The limits of detection and quantification, respectively, were 0.00488 and 0.03906 μg/mL for quercetin, 0.62500 and 2.50000 μg/mL for bisdemethoxycurcumin, 0.07813 and 0.31250 μg/mL for demethoxycurcumin, and 0.03906 and 0.07813 μg/mL for curcumin. The percent relative intra day standard deviation (% RSD) values were 0.432 ─ 0.806 μg/mL, 0.576 ─ 0.723 μg/mL, 0.635 ─ 0.752 μg/mL and 0.655 ─ 0.732 μg/mL for quercetin, bisdemethoxycurcumin, demethoxycurcumin and curcumin, respectively, and those for intra day precision were 0.323 ─ 0.968 μg/mL, 0.805 ─ 0.854 μg/mL, 0.078 ─ 0.844 μg/mL and 0.275 ─ 0.829 μg/mL, respectively. The intra day accuracies were 99.589% ─ 100.821%, 98.588% ─ 101.084%, 9.289% ─ 100.88%, and 98.292% ─ 101.022% for quercetin, bisdemethoxycurcumin, demethoxycurcumin and

  12. Quercetin stabilizes apolipoprotein E and reduces brain Aβ levels in amyloid model mice.

    PubMed

    Zhang, Xilin; Hu, Jin; Zhong, Li; Wang, Na; Yang, Longyu; Liu, Chia-Chen; Li, Huifang; Wang, Xin; Zhou, Ying; Zhang, Yunwu; Xu, Huaxi; Bu, Guojun; Zhuang, Jiangxing

    2016-09-01

    Apolipoprotein E (apoE) is a major cholesterol carrier that regulates lipid homeostasis by mediating lipid transport from one tissue or cell type to another. In the central neural system (CNS), apoE is mainly produced by astrocytes, and transports cholesterol to neurons via apoE receptors, which are members of the low-density lipoprotein receptor family. The APOEε4 gene is a strong genetic risk factor for late-onset sporadic Alzheimer's disease (AD), likely through its strong effect on the accumulation of amyloid-β (Aβ) peptide. ApoE protein levels in cerebrospinal fluid (CSF) and plasma are reduced in APOEε4 carriers and in patients with AD. Furthermore, altered cholesterol levels are also associated with the risk of AD. Aβ accumulation, oligomerization and deposition in the brain are central to the pathogenesis of AD. Mounting evidence demonstrates that apoE and apoE receptors play important roles in these processes. Astrocyte-derived apoE is pivotal for cerebral cholesterol metabolism and clearance of Aβ. Thus, we hypothesized that increased apoE in the brain may be an effective therapeutic strategy for AD. We report here that quercetin can significantly increase apoE levels by inhibiting apoE degradation in immortalized astrocytes. Importantly, we show that oral administration of quercetin significantly increased brain apoE and reduced insoluble Aβ levels in the cortex of 5xFAD amyloid model mice. Our results demonstrate that quercetin increases apoE levels through a novel mechanism and can be explored as a novel class of drug for AD therapy. PMID:27114256

  13. Separation of (+)-catechin and quercetin on mesoporous MCM-41 composites: Dynamics of the sorption of flavonoids

    NASA Astrophysics Data System (ADS)

    Karpov, S. I.; Korabel'nikova, E. O.

    2015-06-01

    An analysis of conditions for chromatographic separation of quercetin and (+)-catechin based on experimental data and using the equations of an asymptotic model of sorption dynamics for substances characterized by convex isotherms of sorption is presented. The effects of the equilibrium (distribution coefficient) and kinetic (diffusion coefficient) factors on the dynamics of the sorption of flavonoids by ordered mesoporous material of the MCM-41 type and its composites with grafted organosilane groups is considered. The effects of kinetic and equilibrium parameters on the broadening of adsorption fronts is demonstrated with allowance for the inner and outer diffusion limitations of the sorption process.

  14. Anti-inflammatory Effect of Mesenchymal Stromal Cell Transplantation and Quercetin Treatment in a Rat Model of Experimental Cerebral Ischemia.

    PubMed

    Zhang, Lan-Lan; Zhang, Hong-Tian; Cai, Ying-Qian; Han, Yan-Jiang; Yao, Fang; Yuan, Zhao-Hu; Wu, Bing-Yi

    2016-10-01

    Here, we have investigated the synergistic effect of quercetin administration and transplantation of human umbilical cord mesenchymal stromal cells (HUMSCs) following middle cerebral artery occlusion in rat. Combining quercetin treatment with delayed transplantation of HUMSCs after local cerebral ischemia significantly (i) improved neurological functional recovery; (ii) reduced proinflammatory cytokines (interleukin(IL)-1β and IL-6), increased anti-inflammatory cytokines (IL-4, IL-10, and transforming growth factor-β1), and reduced ED-1 positive areas; (iii) inhibited cell apoptosis (caspase-3 expression); and (iv) improved the survival rate of HUMSCs in the injury site. Altogether, our results demonstrate that combined HUMSC transplantation and quercetin treatment is a potential strategy for reducing secondary damage and promoting functional recovery following cerebral ischemia. PMID:27008429

  15. Quercetin exhibits a specific fluorescence in cellular milieu: a valuable tool for the study of its intracellular distribution.

    PubMed

    Nifli, Artemissia-Phoebe; Theodoropoulos, Panayiotis A; Munier, Sylvie; Castagnino, Chantal; Roussakis, Emmanuel; Katerinopoulos, Haralambos E; Vercauteren, Joseph; Castanas, Elias

    2007-04-18

    The elaboration of novel techniques for flavonoid intracellular tracing would elucidate the compounds' absorption and bioavailability and assist molecular and pharmacological approaches, as they are promising candidates for drug development. This study exploited the properties of quercetin (3,3',4',5,7-pentahydroxyflavone), found in high concentrations in the majority of edible plants. Through the use of UV-vis spectroscopy, confocal microscopy, and HPLC-ESI-MS, native quercetin, at physiologically relevant concentrations, was found to exhibit a specific fluorescence (488 nmex/500-540 nmem) upon internalization. This fluorescence shift is due to a non-covalent binding to intracellular targets (probably proteins) and compatible with the settings applied in confocal microscopy. This property provides a valuable, selective alternative technique for quercetin tracing in cellular systems, permitting the quantitative evaluation of its transit at pharmacologically relevant concentrations and the validation of a number of already described molecular functions. PMID:17385883

  16. Fabrication of Hollow Porous Silica Using a Combined Emulsion Sol-Gel Process and Amphiphilic Triblock Copolymer for Loading of Quercetin.

    PubMed

    Lee, Sang Gil; Kim, Young Ho; Bae, Jun Tae; Lee, Chung Hee; Pyo, Hyeong Bae; Kang, Kuk Hyoun; Lee, Dong Kyu

    2015-10-01

    Flavonoids have recently attracted significant interest as potential reducing agents, hydrogen-donating antioxidants, and singlet oxygen-quenchers. Quercetin, in particular, induces the expression of a gene, known to be associated with cell protection, in dose- and time-dependent manners. Therefore, quercetin may be used as an effective cosmeceutical material useful in the protection of dermal skin. In this study, hollow porous silica spheres used to load quercetin were prepared by using a combined emulsion sol-gel process and triblock copolymer as a template. Fabrication of hollow porous silica spheres was performed under various conditions such as the molar ratios of H2O/TEOS (Rw) and weight ratios of poloxamer 184/poloxamer 407. Loading of quercetin in hollow porous silica spheres was devised to improve the stability of quercetin and to consider the possibility as a raw cosmetic material. The surface of inclusion complexes of quercetin in hollow porous silicas was modified to enhance the stability of quercetin. The physicochemical properties of the samples were investigated using scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA)-differential thermal analysis (DTA) and Brunauer-Emmett-Teller (BET) surface area and porosity analysis. Determination of quercetin concentration was carried out by high-performance liquid chromatography (HPLC) analysis. PMID:26726443

  17. [Effect of quercetin on some indicators of the proteinase-proteinase inhibitor system in rats upon administration of cobalt chloride to them].

    PubMed

    Kaliman, P A; Samokhin, A A; Samokhina, L M

    2001-01-01

    The results of quercetin effect on some changes of proteinase--proteinase inhibitor system parameters in rats under cobalt chloride injection are shown. It was established that preliminary quercetin administration prevened neutral proteinase activation and alpha-2-macroglobulin activity decreasing after 2 h of cobalt chloride influence. PMID:12199071

  18. Quantitative Analysis of Vasodilatory Action of Quercetin on Intramural Coronary Resistance Arteries of the Rat In Vitro

    PubMed Central

    Monori-Kiss, Anna; Monos, Emil; Nádasy, György L.

    2014-01-01

    Background Dietary quercetin improves cardiovascular health, relaxes some vascular smooth muscle and has been demonstrated to serve as a substrate for the cyclooxygenase enzyme. Aims 1. To test quantitatively a potential direct vasodilatory effect on intramural coronary resistance artery segments, in different concentrations. 2. To scale vasorelaxation at different intraluminal pressure loads on such vessels of different size. 3. To test the potential role of prostanoids in vasodilatation induced by quercetin. Methods Coronary arterioles (70–240 µm) were prepared from 24 rats and pressurized in PSS, using a pressure microangiometer. Results The spontaneous tone that developed at 50 mmHg was relaxed by quercetin in the 10−9 moles/lit concentration (p<0.05), while 10−5 moles/lit caused full relaxation. Significant relaxation was observed at all pressure levels (10–100 mmHg) at 10−7 moles/lit concentration of quercetin. The cyclooxygenase blocker indomethacin (10−5moles/lit) induced no relaxation but contraction when physiological concentrations of quercetin were present in the tissue bath (p<0.02 with Anova), this contraction being more prominent in smaller vessels and in the higher pressure range (p<0.05, Pearson correlation). A further 2–8% contraction could be elicited by the NO blocker L-NAME (10−4 moles/lit). Conclusion These results demonstrate that circulating levels of quercetin (10−7 moles/lit) exhibit a substantial coronary vasodilatory effect. The extent of it is commeasurable with that of several other physiological mechanisms of coronary blood flow control. At least part of this relaxation is the result of an altered balance toward the production of endogenous vasodilatory prostanoids in the coronary arteriole wall. PMID:25144688

  19. Soothing and anti-itch effect of quercetin phytosome in human subjects: a single-blind study

    PubMed Central

    Maramaldi, Giada; Togni, Stefano; Pagin, Ivan; Giacomelli, Luca; Cattaneo, Roberta; Eggenhöffner, Roberto; Burastero, Samuele E

    2016-01-01

    Background We evaluated the ability of quercetin, a natural antioxidant formulated in a specific delivery system, to reduce skin inflammation induced by a variety of stimuli, including UV radiation, stimulation with a histamine solution, or contact with chemical irritants. In particular, we tested the soothing and anti-itch effect of Quercevita®, 1% cream for external use, a formulation characterized by a phospholipids-based delivery system. Patients and methods The study was a monocentric, single blind trial that enrolled a group of 30 healthy volunteers. The back of each subject was examined to identify four quadrants with no previous skin damage or naevi that were treated in order to induce a controlled and reversible form of skin stress. The areas were treated as follows: no product; Quercevita® 1% cream, 2 mg/cm2; placebo; positive control (a commercially available topical formulation containing 1% dexchlorpheniramine). Results Only quercetin phospholipids 1% and dexchlorpheniramine 1% achieved a significant reduction in erythema with comparable results: (–10.05% [P=0.00329] for quercetin phospholipids 1% vs –14.05% [P=0.00046] for the positive control). Moreover, quercetin phospholipids 1% and dexchlorpheniramine 1% were both associated with a significant decrease in mean wheal diameter: (–13.25% and –12.23% for dexchlorpheniramine 1%, respectively). Similar findings were reported for the other tested parameters. Conclusion Quercetin has a skin protective effect against damage caused by a variety of insults, including UV radiation, histamine, or contact with toxic chemical compounds. Indeed, quercetin is able to reduce redness, itching, and inflammation of damaged skin; it may also help restore skin barrier function, increasing hydration, and reducing water loss. PMID:27013898

  20. Antiproliferative activity of long chain acylated esters of quercetin-3-O-glucoside in hepatocellular carcinoma HepG2 cells.

    PubMed

    Sudan, Sudhanshu; Rupasinghe, Hp Vasantha

    2015-11-01

    Despite their strong role in human health, poor bioavailability of flavonoids limits their biological effects in vivo. Enzymatically catalyzed acylation of fatty acids to flavonoids is one of the approaches of increasing cellular permeability and hence, biological activities. In this study, six long chain fatty acid esters of quercetin-3-O-glucoside (Q3G) acylated enzymatically and were used for determining their antiproliferative action in hepatocellular carcinoma cells (HepG2) in comparison to precursor compounds and two chemotherapy drugs (Sorafenib and Cisplatin). Fatty acid esters of Q3G showed significant inhibition of HepG2 cell proliferation by 85 to 90% after 6 h and 24 h of treatment, respectively. The cell death due to these novel compounds was associated with cell-cycle arrest in S-phase and apoptosis observed by DNA fragmentation, fluorescent microscopy and elevated caspase-3 activity and strong DNA topoisomerase II inhibition. Interestingly, Q3G esters showed significantly low toxicity to normal liver cells than Sorafenib (P < 0.05), a chemotherapy drug for hepatocellular carcinoma. Among all, oleic acid ester of Q3G displayed the greatest antiproliferation action and a high potential as an anti-cancer therapeutic. Overall, the results of the study suggest strong antiproliferative action of these novel food-derived compounds in treatment of cancer. PMID:25681471

  1. Retroviral vectors encoding ADA regulatory locus control region provide enhanced T-cell-specific transgene expression

    PubMed Central

    2009-01-01

    Background Murine retroviral vectors have been used in several hundred gene therapy clinical trials, but have fallen out of favor for a number of reasons. One issue is that gene expression from viral or internal promoters is highly variable and essentially unregulated. Moreover, with retroviral vectors, gene expression is usually silenced over time. Mammalian genes, in contrast, are characterized by highly regulated, precise levels of expression in both a temporal and a cell-specific manner. To ascertain if recapitulation of endogenous adenosine deaminase (ADA) expression can be achieved in a vector construct we created a new series of Moloney murine leukemia virus (MuLV) based retroviral vector that carry human regulatory elements including combinations of the ADA promoter, the ADA locus control region (LCR), ADA introns and human polyadenylation sequences in a self-inactivating vector backbone. Methods A MuLV-based retroviral vector with a self-inactivating (SIN) backbone, the phosphoglycerate kinase promoter (PGK) and the enhanced green fluorescent protein (eGFP), as a reporter gene, was generated. Subsequent vectors were constructed from this basic vector by deletion or addition of certain elements. The added elements that were assessed are the human ADA promoter, human ADA locus control region (LCR), introns 7, 8, and 11 from the human ADA gene, and human growth hormone polyadenylation signal. Retroviral vector particles were produced by transient three-plasmid transfection of 293T cells. Retroviral vectors encoding eGFP were titered by transducing 293A cells, and then the proportion of GFP-positive cells was determined using fluorescence-activated cell sorting (FACS). Non T-cell and T-cell lines were transduced at a multiplicity of infection (MOI) of 0.1 and the yield of eGFP transgene expression was evaluated by FACS analysis using mean fluorescent intensity (MFI) detection. Results Vectors that contained the ADA LCR were preferentially expressed in T

  2. Protein carbonylation after traumatic brain injury: cell specificity, regional susceptibility, and gender differences.

    PubMed

    Lazarus, Rachel C; Buonora, John E; Jacobowitz, David M; Mueller, Gregory P

    2015-01-01

    Protein carbonylation is a well-documented and quantifiable consequence of oxidative stress in several neuropathologies, including multiple sclerosis, Alzheimer׳s disease, and Parkinson׳s disease. Although oxidative stress is a hallmark of traumatic brain injury (TBI), little work has explored the specific neural regions and cell types in which protein carbonylation occurs. Furthermore, the effect of gender on protein carbonylation after TBI has not been studied. The present investigation was designed to determine the regional and