PMID: 

Interv Med Appl Sci. 2019 Mar ;11(1):55-59. PMID: 32148903

Abstract Title: 

Effects of flavonol quercetin on activity of lipid peroxide oxidation in experimental bacterial-immune periodontitis.

Abstract: 

The article presents the results of lipid peroxidation activity in blood serum, which were assessed on the base changes in the level of oxidative modification of proteins, TBA-active products, and total amount of nitrogen (II) oxide metabolites (NO + NO). Indices were determined on the 14day of development in experimental periodontitis both without correction, and in condition treatment with a water-soluble flavonol quercetin (corvitin). The treated animals take intramuscular injections of corvitin in a dose 100 mg/kg weight for 7 days. For further testing, blood serum was selected. The results were statistically analyzed using parametric and non-parametric indices. In this investigation, characterized dynamics of changes in the indices of oxidative processes activity were revealed both during the periodof formation and the course of periodontitis. In particular, it was found that, for the period of the most expressed inflammatory reaction in the periodontal complex, intensive increase in the level of reactive forms of oxygen. The treatment with flavonol quercetin for 7 days resulted in stabilization of free radical processes and the suppression of the inflammatory reaction.

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PMID: 

Interv Med Appl Sci. 2019 Mar ;11(1):60-64. PMID: 32148904

Abstract Title: 

Effects of quercetin on antioxidant potential in the experimental periodontitis development.

Abstract: 

The results of experimental research of antioxidant system are presented in this article. Superoxide dismutase activity, catalase, and ceruloplasmin have been determined on the 7and 14days of experimental periodontitis development both without correction and with the injection of a water-soluble quercetin drug (corvitin). Hence, there was a decrease in superoxide dismutase activity, intensive increase in catalase activity, and ceruloplasmin maintenance in the blood serum during acute period of inflammatory process. The usage of flavonoid for 7  days resulted in stabilization of radical oxidation due to reduction of superoxide dismutase activity, maintenance at the high-level catalase activity, and ceruloplasmin concentration in the rat's blood plasma with experimental bacterial-immune periodontitis.

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PMID: 

Reprod Sci. 2020 Mar 10. Epub 2020 Mar 10. PMID: 32157554

Abstract Title: 

Quercetin Prevents Lipopolysaccharide-Induced Experimental Preterm Labor in Mice and Increases Offspring Survival Rate.

Abstract: 

Premature labor is still a worldwide problem, causing serious social economic burden and family burden. Currently, there is no effective way to prevent preterm labor. Since inflammation increases the risk of preterm birth and quercetin is reported to have anti-inflammation, immune-enhancement, and antioxidative effects, this study aims to explore whether quercetin exerts inhibitory effect on preterm labor in mice and increases offspring survival. Lipopolysaccharide (LPS) is one of the commonly used drugs in the inflammatory animal model of preterm birth. On day 15 of pregnancy, mice received a dose of vehicle phosphate-buffered saline (PBS) or a dose of quercetin (low concentration, 30 mg/kg; medium concentration, 90 mg/kg; high concentrations, 150 mg/kg) via oral gavage. After 2 h, mice received a dose of LPS (50 μg/kg) or vehicle intraperitoneally (i.p.). In the absence of quercetin, a 100% incidence of preterm labor was observed in LPS-treated mice, and the fetuses wereall died. Medium concentration of quercetin significantly prevented 63.5% of LPS-induced inflammatory preterm labor, and the survival rate of pups on day 22 was 83.76%. Specifically, quercetin significantly inhibited LPS-induced upregulation of NF-kappa-B/P65(RELA), AP-1/C-JUN(JUN), cyclooxygenase-2(PTGS2), and interleukin 6(IL6) in mice myometrium on mRNA level and inhibited the upregulation of P65 and C-JUN on protein level. Based on these observations, we concluded that quercetin exerts inhibitory effect on LPS-induced experimental mice preterm labor and increases offspring survival througha mechanism involving NF-κB/AP-1 pathway.

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PMID: 

Mol Pharm. 2020 Mar 20. Epub 2020 Mar 20. PMID: 32159961

Abstract Title: 

Combination Therapy of Doxorubicin and Quercetin on Multidrug-Resistant Breast Cancer and Their Sequential Delivery by Reduction-Sensitive Hyaluronic Acid-Based Conjugate/d-α-Tocopheryl Poly(ethylene glycol) 1000 Succinate Mixed Micelles.

Abstract: 

The therapeutic efficacy of chemotherapy in many types of hematological malignancies and solid tumors is dramatically hindered by multidrug resistance (MDR). This work presents a combination strategy of pretreatment of MDA-MB-231/MDR1 cells with quercetin (QU) followed by doxorubicin (DOX) to overcome MDR, which can be delivered by mixed micelles composed of the reduction-sensitive hyaluronic acid-based conjugate and d-α-tocopheryl poly(ethylene glycol) 1000 succinate. The combination strategy can enhance the cytotoxicity of DOX on MDA-MB-231/MDR1 cells by increasing intracellular DOX accumulation and facilitating DOX-induced apoptosis. The probable MDR reversal mechanisms are that the pretreatment cells with QU-loaded mixed micelles downregulate P-glycoprotein expression to decrease DOX efflux as well as initiate mitochondria-dependent apoptotic pathways to accelerate DOX-induced apoptosis. In addition, this combination strategy can not only potentiatetumor-targeting efficiency but also enhance the antitumor effect in MDA-MB-231/MDR1-bearing nude mice without toxicity or side effects. This research suggests that the co-administration of natural compounds and chemotherapeutic drugs could be an effective strategy to overcome tumor MDR, which deserves further exploration.

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PMID: 

J Basic Clin Physiol Pharmacol. 2020 Mar 11. Epub 2020 Mar 11. PMID: 32160160

Abstract Title: 

Quercetin modulates granulosa cell mRNA androgen receptor gene expression in dehydroepiandrosterone-induced polycystic ovary in Wistar rats via metabolic and hormonal pathways.

Abstract: 

Background It is estimated that about 5-10% of women suffer from polycystic ovarian syndrome (PCOS) which is a major cause of female reproductive dysfunction. This study examined the role of quercetin on dehydroepiandrosterone (DHEA)-induced PCO in Wistar rats. Methods Twenty-eight pre-pubertal female Wistar rats that are 21 days old weighing 16-21 g were sorted into four groups (n = 7). Group I served as control and was given distilled water only, Group II were injected with 6 mg/100 g BW of DHEA in 0.2 mL of corn oil subcutaneously, Group III received 100 mg/kg BW of quercetin orally and Group IV received 6 mg/100 g BW of DHEA in 0.2 mL of corn oil subcutaneously and 100 mg/kg BW of quercetin orally. Rats were sacrificed after 15 days by cervical dislocation method. Blood samples and ovaries were collected for hormonal, biochemical, and histopathological analysis and expressions of mRNA androgen receptor gene were determined using RT-qPCR. All data were analysed using one-way ANOVA. Results A significant decrease (p

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PMID: 

Nutrients. 2020 Mar 10 ;12(3). Epub 2020 Mar 10. PMID: 32164219

Abstract Title: 

Effect of Quercetin Treatment on Mitochondrial Biogenesis and Exercise-Induced AMP-Activated Protein Kinase Activation in Rat Skeletal Muscle.

Abstract: 

The purpose of this study was to evaluate the effect of chronic quercetin treatment on mitochondrial biogenesis, endurance exercise performance and activation levels of AMP-activated protein kinase (AMPK) in rat skeletal muscle. Rats were assigned to a control or quercetin group and were fed for 7 days. Rats treated with quercetin showed no changes in the protein levels of citrate synthase or cytochrome C oxidase IV or those of sirtuin 1, peroxisome proliferator-activated receptor gamma coactivator-1α or phosphorylated AMPK. After endurance swimming exercise, quercetin-treated rats demonstrated no differences in blood and muscle lactate levels or glycogen utilization speed compared to control rats. These results indicate that quercetin treatment does not stimulate mitochondrial biogenesis in skeletal muscle and does not influence metabolism in a way that might enhance endurance exercise capacity. On the other hand, the AMPK phosphorylation level immediately after exercise was significantly lower in quercetin-treated muscles, suggesting that quercetin treatment might provide a disadvantage to muscle adaptation when administered with exercise training. The molecular results of this study indicate that quercetin treatment may not be advantageous for improving endurance exercise performance, at least after high-dose and short-term therapy.

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PMID: 

Int J Biol Sci. 2020 ;16(7):1121-1134. Epub 2020 Feb 10. PMID: 32174789

Abstract Title: 

Quercetin reverses docetaxel resistance in prostate cancer via androgen receptor and PI3K/Akt signaling pathways.

Abstract: 

Docetaxel is the first-line chemotherapy agent for metastatic prostate cancer. However, the emergence of resistance diminishes its efficacy and limits the survival benefit. Quercetin is a dietary flavonoid which has been shown to have multiple anti-cancer effects. Also, quercetin has been reported to reverse chemo-resistance in many other cancers. This study was to determine whether quercetin could reverse docetaxel resistance in prostate cancer cells and xenograft models, thereby exploring the underlying mechanism. Depending on the docetaxel-resistant cells (LNCaP/R, PC-3/R) which were established from docetaxel-sensitive cells (LNCaP, PC-3), it was demonstrated that quercetin could reverse docetaxel resistance in prostate cancer on proliferation, colony formation, migration, invasion and apoptosis. Although single docetaxel application had little effect on docetaxel-resistant cells, combining docetaxel with quercetin was significantly effective. Combination therapy could maximally inhibited PI3K/Akt pathway and promoted apoptosis. As shown bystudy, xenograft tumors treated by docetaxel with quercetin had poorest growth. Then, to investigate the underlying mechanisms, the differences among parental cells, docetaxel-resistant subclones and quercetin treated resistant subclones were evaluated. It was found that docetaxel-resistant subclones had stronger activation of androgen receptor and PI3K/Akt pathway, more remarkable mesenchymal and stem-like cell phenotypes, and more P-gp expression than that of parental cells. Interestingly, quercetin could reverse these transformations. Our data revealed that quercetin had docetaxel-resistance reversal effect bothandand provided in-depth support for clinical use of quercetin in docetaxel-resistant prostate cancer.

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PMID: 

Cell Biosci. 2020 ;10:32. Epub 2020 Mar 10. PMID: 32175075

Abstract Title: 

Quercetin and cancer: new insights into its therapeutic effects on ovarian cancer cells.

Abstract: 

Ovarian cancer is known as a serious malignancy that affects women's reproductive tract and can considerably threat their health. A wide range of molecular mechanisms and genetic modifications have been involved in ovarian cancer pathogenesis making it difficult to develop effective therapeutic platforms. Hence, discovery and developing new therapeutic approaches are required. Medicinal plants, as a new source of drugs, could potentially be used alone or in combination with other medicines in the treatment of various cancers such as ovarian cancer. Among various natural compounds, quercetin has shown great anti-cancer and anti-inflammatory properties. In vitro and in vivo experiments have revealed that quercetin possesses a cytotoxic impact on ovarian cancer cells. Despite obtaining good results both in vitro and in vivo, few clinical studies have assessed the anti-cancer effects of quercetin particularly in the ovarian cancer. Therefore, it seems that further clinical studies may introduce quercetin as therapeutic agent alone or in combination with other chemotherapy drugs to the clinical setting. Here, we not only summarize the anti-cancer effects of quercetin but also highlight the therapeutic effects of quercetin in the ovarian cancer.

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PMID: 

Life Sci. 2020 Mar 13:117552. Epub 2020 Mar 13. PMID: 32179074

Abstract Title: 

Anti-fibrosis activity of quercetin attenuates rabbit tracheal stenosis via the TGF-β/AKT/mTOR signaling pathway.

Abstract: 

AIMS: This study aimed to explore the possible mechanism of trauma-induced laryngotracheal stenosis and potential protective and therapeutic efficacy of quercetin on trauma-induced laryngotracheal stenosis.MAIN METHODS: The expression and activity of fibrotic factors [interleukin (IL)-6, IL-8, autophagy related 5 (ATG5), collagen (COL)-1, tumor growth factor (TGF)-β COL-3, microtubule-associated proteins 1A/1B light chain 3A (LC3), and vascular endothelial growth factor (VEGF)] and fibrotic signaling mediators [mammalian target of rapamycin (mTOR) and phosphorylated AKT (pAKT)] were detected by real-time quantitative PCR (qRT-PCR), ELISA, Western blot, and immunohistochemical staining, respectively, in the lipopolysaccharide (LPS)-induced WI-38 (a human embryonic lung fibroblast cell line) cellular fibrotic model and a trauma-induced rabbit tracheal stenosis model, with and without quercetin treatment.KEY FINDINGS: Pre-treatment with quercetin significantly reversed the LPS-induced upregulation of pro-fibrotic factors (IL-6, IL-8, COL-1, COL-3, LC3) and fibrotic signaling mediators (mTOR and AKT), and it induced the downregulation of ATG5 in the WI-38 cells. Furthermore, the anti-fibrotic activity of quercetin was confirmed in the trauma-induced rabbit tracheal stenosis model. Thus, the nasogastric administration of quercetin attenuated the tracheal stenosis of the rabbit tracheal stenosis model, in addition to effectively reversing an increase in pro-fibrotic factors (VEGF, IL-6, TGF-β, COL-1, and COL-3) and fibrotic signaling mediators (mTOR and AKT), as well as downregulating ATG5 of the rabbit tracheal stenosis model.SIGNIFICANCE: Quercetin exhibits anti-fibrotic activity by inhibiting pro-fibrotic factors and AKT/mTOR signaling pathway, in addition to activating autophagy activity. This study provided experimental evidence supporting the application of quercetin in tracheal stenosis, clinically.

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PMID: 

Int J Dev Neurosci. 2020 Mar 17. Epub 2020 Mar 17. PMID: 32181519

Abstract Title: 

Quercetin prevents alterations of behavioral parameters, delta-aminolevulinic dehydratase activity and oxidative damage in brain of rats in a prenatal model of autism.

Abstract: 

Autism is a neuropathology characterized by behavioral disorders. Considering that oxidative stress is involved in the pathophysiology of this disease, we evaluated the effects of quercetin, a flavonoid with antioxidant and neuroprotective properties, in an experimental model of autism induced by valproic acid (VPA). Twelve pregnant female rats were divided into four groups (control, quercetin, VPA, VPA+quercetin). Quercetin (50 mg/kg) was administered orally to the animals from gestational days 6.5 to 18.5, and VPA (800 mg/kg) was administered orally in a single dosage on gestational day 12.5. Behavioral tests such as open field, social interaction, and tail flick nociceptive assays were performed on pups between 30 and 40 days old, after which the animals were euthanized. Cerebral cortex, hippocampus, striatum, and cerebellum were collected for evaluation of oxidative stress parameters. The pups exposed to VPA during the gestational period showed reduced weight gain, increased latency in the open field and tail flick tests, reduced time of social interaction, accompanied by changes in oxidative stress parameters mainly in the hippocampus and striatum. Prenatal treatment with quercetin prevented the behavioral changes and damage caused by oxidative stress, possibly due to its antioxidant action. Our findings demonstrated that quercetin has neuroprotective effects in an animal model of autism, suggesting that this natural molecule could be an important therapeutic agent for treatment of autism spectrum disorders.

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