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Yangmee Kim - One of the best experts on this subject based on the ideXlab platform.
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Rhamnetin exhibits anti tuberculosis activity and protects against lung inflammation
Bulletin of The Korean Chemical Society, 2016Co-Authors: Min Jun Kim, Dasom Jeon, Chulhee Kwak, Sungweon Ryoo, Yangmee KimAbstract:Rhamnetin, a natural flavonoid found in cloves and berries has been reported to show anti-inflammatory activities in lipopolysaccharide-stimulated RAW264.7 cells and may be a potent inhibitor for extracellular signal-regulated kinase 1 (ERK1) and c-Jun N-terminal kinase. Here, we showed that Rhamnetin has antimycobacterial effects on Mycobacterium tuberculosis (MT) H37Rv, multi-drug-, and extensively drug-resistant clinical isolates. We also investigated the effect of Rhamnetin on interferon (IFN)-γ-stimulated human lung fibroblast MRC-5 cells, since MT infection causes intensive lung inflammation. Rhamnetin suppressed mRNA levels of tumor necrosis factor-α, interleukin (IL)-1β, IL-6, IL-12, and matrix metalloproteinase-1. Furthermore, it inhibited IFN-γ-mediated stimulation of ERK1 and p38 mitogen-activated protein kinase in MRC-5 cells. These results showed that Rhamnetin has potent anti-tuberculosis activities and effectively suppresses lung inflammation, implying that Rhamnetin can be a potent anti-tuberculosis dietary agent.
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Rhamnetin Exhibits Anti‐Tuberculosis Activity and Protects against Lung Inflammation
Bulletin of the Korean Chemical Society, 2016Co-Authors: Min Jun Kim, Dasom Jeon, Chulhee Kwak, Sungweon Ryoo, Yangmee KimAbstract:Rhamnetin, a natural flavonoid found in cloves and berries has been reported to show anti-inflammatory activities in lipopolysaccharide-stimulated RAW264.7 cells and may be a potent inhibitor for extracellular signal-regulated kinase 1 (ERK1) and c-Jun N-terminal kinase. Here, we showed that Rhamnetin has antimycobacterial effects on Mycobacterium tuberculosis (MT) H37Rv, multi-drug-, and extensively drug-resistant clinical isolates. We also investigated the effect of Rhamnetin on interferon (IFN)-γ-stimulated human lung fibroblast MRC-5 cells, since MT infection causes intensive lung inflammation. Rhamnetin suppressed mRNA levels of tumor necrosis factor-α, interleukin (IL)-1β, IL-6, IL-12, and matrix metalloproteinase-1. Furthermore, it inhibited IFN-γ-mediated stimulation of ERK1 and p38 mitogen-activated protein kinase in MRC-5 cells. These results showed that Rhamnetin has potent anti-tuberculosis activities and effectively suppresses lung inflammation, implying that Rhamnetin can be a potent anti-tuberculosis dietary agent.
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Rhamnetin is a potent inhibitor of extracellular signal regulated kinase 1 and c jun n terminal kinase 1
Bulletin of The Korean Chemical Society, 2015Co-Authors: Hum Nath Jnawali, Dasom Jeon, Young-gun Park, Eunjung Lee, Yong-seok Heo, Yangmee KimAbstract:Rhamnetin is a flavonoid found in cloves and vegetables. Previously, we found that Rhamnetin showed anti-inflammatory activity in lipopolysaccharide-stimulated RAW264.7 cells, mediated by actions on mitogen-activated protein kinases pathways. Here, we investigated interactions between extracellular signal-regulated kinase 1 (ERK1) and Rhamnetin. Based on docking study, we propose a binding model of Rhamnetin and ERK1, where the 4′-hydroxyl groups of the B-ring and the 5-hydroxyl group of the A-ring of Rhamnetin play key roles. In a fluorescence quenching experiment, Rhamnetin exhibited high binding affinity to ERK1. We found that Rhamnetin has an IC50 value similar to that of the ERK1 inhibitor U0126 in ERK1 kinase assays, as well as to that of the JNK1 inhibitor SP600125 in JNK1 kinase assays. These results imply that Rhamnetin may be a candidate inhibitor of ERK1 and JNK1, with potent anti-inflammatory activity.
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Rhamnetin Is a Potent Inhibitor of Extracellular Signal‐regulated Kinase 1 and c‐Jun N‐Terminal Kinase 1
Bulletin of the Korean Chemical Society, 2015Co-Authors: Hum Nath Jnawali, Dasom Jeon, Young-gun Park, Eunjung Lee, Yong-seok Heo, Yangmee KimAbstract:Rhamnetin is a flavonoid found in cloves and vegetables. Previously, we found that Rhamnetin showed anti-inflammatory activity in lipopolysaccharide-stimulated RAW264.7 cells, mediated by actions on mitogen-activated protein kinases pathways. Here, we investigated interactions between extracellular signal-regulated kinase 1 (ERK1) and Rhamnetin. Based on docking study, we propose a binding model of Rhamnetin and ERK1, where the 4′-hydroxyl groups of the B-ring and the 5-hydroxyl group of the A-ring of Rhamnetin play key roles. In a fluorescence quenching experiment, Rhamnetin exhibited high binding affinity to ERK1. We found that Rhamnetin has an IC50 value similar to that of the ERK1 inhibitor U0126 in ERK1 kinase assays, as well as to that of the JNK1 inhibitor SP600125 in JNK1 kinase assays. These results imply that Rhamnetin may be a candidate inhibitor of ERK1 and JNK1, with potent anti-inflammatory activity.
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Anti-inflammatory Activity of Rhamnetin and a Model of Its Binding to c-Jun NH2-Terminal Kinase 1 and p38 MAPK
Journal of natural products, 2014Co-Authors: Hum Nath Jnawali, Eunjung Lee, Yong-seok Heo, Ki-woong Jeong, Areum Shin, Yangmee KimAbstract:Rhamnetin (1), a commonly occurring plant O-methylated flavonoid, possesses antioxidant properties. To address the potential therapeutic efficacy of 1, its anti-inflammatory activity and mode of action in mouse macrophage-derived RAW264.7 cells stimulated with lipopolysaccharide (LPS) or interferon (IFN)-γ were investigated. Rhamnetin (1) suppressed mouse tumor necrosis factor (mTNF)-α, mouse macrophage inflammatory protein (mMIP)-1, and mMIP-2 cytokine production in LPS-stimulated macrophages. A nontoxic dose of 1 suppressed nitric oxide production. It was found that the anti-inflammatory effects of 1 are mediated by actions on the p38 mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and cyclooxygenase (COX)-2 pathways in LPS- or IFN-γ-stimulated RAW264.7 cells. It was determined that 1 binds to human JNK1 (9.7 × 108 M–1) and p38 MAPK (2.31 × 107 M–1) with good affinity. The binding model showed interactions with the 3′- and 4′-hydroxy g...
Peter Rüedi - One of the best experts on this subject based on the ideXlab platform.
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Rhamnetin 3-p-coumaroylrhamninoside from Rhamnus petiolaris.
Phytochemistry, 1994Co-Authors: Meltem Ozipek, Ihsan Calis, M. Ertan, Peter RüediAbstract:Abstract From the berries of Rhamnus petiolaris a new acylated flavonol glycoside was isolated and identified as Rhamnetin 3-O-[34′-O-(p-couma
Sanjeev Shukla - One of the best experts on this subject based on the ideXlab platform.
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Abstract 1913: Rhamnetin inhibits prostate cancer progression in an autochthonous mouse prostate cancer model
Prevention Research, 2015Co-Authors: Christine Oak, Natarajan Bhaskaran, Sanjay Gupta, Sanjeev ShuklaAbstract:Proceedings: AACR 106th Annual Meeting 2015; April 18-22, 2015; Philadelphia, PA Aging increases oxidative stress and cancer risk. Age-regulated genes viz. FoxO3a and Klotho are stimulated by reactive oxygen species (ROS) due to increased oxidative stress. Klotho, an antiaging gene, modulates stress-induced senescence, and decreases with advancing age, whereas forkhead transcription factor, FoxO3a is known to involve in a paradigm that engages in antioxidant, anti-proliferative and tumor suppressor functions. We have previously demonstrated that FoxO3a is deregulated in human prostate adenocarcinoma and in transgenic adenocarcinoma of the mouse prostate (TRAMP) model that mimics progressive forms of human disease. Here we demonstrate the anticancer effects of Rhamnetin, a dietary flavonoid present in fruits and vegetables, in modulating Klotho and FoxO3a signaling by suppressing ROS. Per-oral feeding of Rhamnetin at 10- and 20-μg/mouse/day (gavaged in 0.2 ml vehicle containing 0.5% methyl cellulose and 0.025% Tween 20) to TRAMP mice for six days per week for 16 weeks, starting at 8 weeks of age, exhibited marked reduction in tumor growth with no signs of metastasis. Rhamnetin feeding to TRAMP resulted in a significant dose-dependent reduction in FoxO3a, in the dorso-lateral prostates. FoxO3a protein was redistributed more in nuclear than the cytosolic compartments after Rhamnetin feeding. Simultaneously, decreased FoxO3a phosphorylation (Ser-253) was observed in the dorso-lateral prostate, which correlated with decreased cytoplasmic retention of FoxO3a with no significant changes in 14-3-3 chaperone protein in the cytosol after Rhamnetin feeding. Additionally, decreased IGF-1 protein expression with subsequent decrease in p-Akt (Ser-473) and p-Erk1/2 (Thr202/Tyr204) was observed after Rhamnetin feeding demonstrating that the decreased nuclear presence of p-Akt (Ser-473) may restrict FoxO3a phosphorylation and its retention in the nucleus along with decreased p-Erk1/2 levels in the dorso-lateral prostate. Furthermore, Rhamnetin intake led to increased levels of SOD2 and significantly enhanced the expression of the thioredoxin/peroxiredoxin (Trx/Prx) in the dorso-lateral prostate. Similar findings were recorded in cell culture studies where Rhamnetin treatment to human prostate cancer LNCaP and PC-3 cells resulted in the restoration of Klotho and FoxO3a in the nucleus. This increase in Klotho and FoxO3a protein expressions in the nucleus may be a decisive factor for increase resistance to oxidative stress and cancer progression. Our finding suggests that Rhamnetin has potential to modulate Klotho and FoxO signaling cascades and could be represented as therapeutic targets in prostate cancer. Citation Format: Christine Oak, Natarajan Bhaskaran, Sanjay Gupta, Sanjeev Shukla. Rhamnetin inhibits prostate cancer progression in an autochthonous mouse prostate cancer model. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1913. doi:10.1158/1538-7445.AM2015-1913
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Abstract 1232: Antiproliferative, antioxidant and antiapoptotic effect of Rhamnetin in human prostate cancer cells
Prevention Research, 2014Co-Authors: Christine Oak, Natarajan Bhaskaran, Sanjay Gupta, Sanjeev ShuklaAbstract:Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Persistent oxidative stress due to generation of reactive oxygen species (ROS) has been associated with malignancy and cancer progression. Using a panel of human prostate cancer cells, we observed increased production of intracellular ROS, compared to normal human prostate epithelial cells, accompanied by elevated expression of antioxidant enzymes viz. superoxide dismutase, catalase, peroxiredoxin-1 and thioredoxin that may be a likely mechanism to endure increased oxidative stress. There is a need for novel antioxidant agent that can effectively suppress the generation of increased ROS in cancer cells. Rhamnetin (3,5,3,4-tetrahydroxy-7-methoxyflavone), remains highest on oxygen radical absorbance capacity scale, however its anti-proliferative activities has not been assessed. Rhamnetin is an O-methylated flavonol, abundantly present in cloves, sweet annie, annual wormwood, green vegetables and orchard grass. Previous studies (Shukla et al. Proc. Amer. Assoc. Cancer Res. 102: 5576, 2011) using androgen-responsive human prostate cancer LNCaP and androgen-refractory PC-3 cells, we have demonstrated that Rhamnetin possess anticancer activity, induces apoptosis, and inhibits cancer cell growth. In the present study we assessed the antioxidant and anti-proliferative ability of rhmanetin in prostate cancer. Treatment of LNCaP and PC-3 cells with 100μM paraquat, an oxidative stress-inducing agent, induced cellular proliferation in both these cells. Treatment of cells with 5-80μM Rhamnetin significantly decreased paraquat-induced ROS production and inhibited cell proliferation in dose-dependent manner. Similar effects were noted with the addition of recombinant Klotho protein to these cells, which is known to offer resistance to oxidative stress at the cellular level. Rhamnetin treatment also increased Klotho protein levels in both cell lines, along with increase in the expression of p53 and p21/waf1. Furthermore, Rhamnetin treatment resulted in the increased expression of caspase-3, caspase-9 causing induction of apoptosis, which may be one of the protective mechanism(s) to decrease cell proliferation and enhance resistance to oxidative stress in cancer cells. Taken together, these results demonstrate that Rhamnetin acts as a potent antioxidant agent, reduces intracellular ROS levels, increases Klotho protein expression, induces apoptosis in prostate cancer cells, which may have a significant role in the inhibition of prostate cancer progression. Citation Format: Christine Oak, Natarajan Bhaskaran, Sanjay Gupta, Sanjeev Shukla. Antiproliferative, antioxidant and antiapoptotic effect of Rhamnetin in human prostate cancer cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1232. doi:10.1158/1538-7445.AM2014-1232
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Abstract 5576: Rhamnetin inhibits human prostate cancer cell growth through cell-cycle arrest by modulating expression and function of key cell-cycle regulators and survival molecules
Prevention Research, 2011Co-Authors: Sanjeev Shukla, Natarajan Bhaskaran, Sanjay GuptaAbstract:Proceedings: AACR 102nd Annual Meeting 2011‐‐ Apr 2‐6, 2011; Orlando, FL Development of effective agents for treatment of prostate cancer has become a national medical priority. Rhamnetin (3,5,3,4-tetrahydroxy-7-methoxyflavone), a natural compound known as O-methylated flavonol, abundantly present in cloves, sweet annie, annual wormwood, green vegetables and orchard grass has shown to possess anti-inflammatory and antioxidant properties. However, the anticancer properties of Rhamnetin have not been fully elucidated. In the present study we demonstrated the molecular mechanism of cell growth inhibition and induction of apoptosis in human prostate carcinoma LNCaP and PC-3 cells by Rhamnetin. Treatment of these cells with Rhamnetin resulted in a dose (5, 10, 20, 40 microM) and time (24, 48 and 72 h) dependent inhibition of growth, G2-S phase arrest of the cell cycle and DNA fragmentation. This effect was associated with a marked decrease in the protein expression of cyclin D1, D2, and E and their activating partner, cyclin-dependent kinase (cdk) 2, 4, and 6, with concomitant upregulation of WAF1/p21, KIP1/p27, INK4a/p16, and INK4c/p18. Rhamnetin treatment also resulted in alteration in Bax/Bcl2 ratio in favor of apoptosis, which was associated with the release of cytochrome-c and induction of apoptotic protease-activating factor-1 (Apaf-1). This effect was found to result in a significant increase in cleaved fragments of caspase-9, -3, and poly (ADP-ribose) polymerase (PARP). Further, Rhamnetin treatment resulted in down modulation of XIAP, survivin, and c-Myc protein expressions. Taken together, we concluded that molecular mechanisms during Rhamnetin-mediated growth inhibition and induction of apoptosis in both androgen-responsive, LNCaP and androgen-refractory, PC-3 cells was due to modulation in cell-cycle machinery, disruption of mitochondrial function, and inhibition of cell survival machinery. For the first time we provide evidence that Rhamnetin acts on potential molecular targets of cell cycle regulation and survival to elicit anticancer effects in prostate cancer cells. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 5576. doi:10.1158/1538-7445.AM2011-5576
Erdogan Unur - One of the best experts on this subject based on the ideXlab platform.
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Rhamnetin improves antioxidant status in the liver of ehrlich solid tumor bearing mice
Medical Science and Discovery, 2020Co-Authors: Mustafa Nisari, Ozlem Bozkurt, Tolga Ertekin, Dilek Ceylan, Neriman Inanc, Hatice Susar Guler, Erdogan UnurAbstract:Objective: Rhamnetin, a flavanol, is in the subclasses of the flavonoids existing in plants. The antioxidant properties of several plants containing flavonoids have been extensively studied in several diseases including cancer. This study investigated the effects of Rhamnetin on tumor masses, oxidant and antioxidant status in the livers of mice bearing Ehrlich solid tumor. Material and Methods: Fifty male Balb/C mice weighing 25-30 g were used in the study. Ten mice were kept for Ehrlich ascites tumor (EAT) cells production and the remaining mice were randomly assigned to four groups containing 10 mice in each as healthy control and treatments receiving 1x106 EAT cells and EAT cells plus 100 µg/kg/day or 200 µg/kg/day Rhamnetin via subcutaneous route. The tumor inhibition rates of Rhamnetin treatments were calculated. The livers were analyzed for malondialdehyde (MDA), superoxide dismutase (SOD) and catalase (CAT) levels. Results: Compare to tumor control, both levels of Rhamnetin suppressed tumor masses throughout the experiment. The MDA levels were increased whereas SOD and CAT activities were reduced by EAT cells injection in the liver of mice. The 100 µg/kg/day Rhamnetin treatment decreased MDA level but 200 µg/kg/day Rhamnetin had no significant effect on increased MDA level. The reduced liver SOD (p<0.001) and CAT (p<0.01) activities were elevated by both levels of Rhamnetin injection. Conclusions: The results of this study have revealed that Rhamnetin suppresses tumor progression and improves antioxidant status in the livers of solid tumor-bearing mice.
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May argyrophilic nucleolar organizing region-associated protein synthesis be used for selecting the most reliable dose of drugs such as Rhamnetin in cancer treatments?
Bratislavske lekarske listy, 2016Co-Authors: Tolga Ertekin, O. Bozkurt, R. Eroz, Mehtap Nisari, D. Bircan, Erdogan UnurAbstract:BACKGROUND Rhamnetin is a flavonoid that has antioxidant, anti-inflammatory and anti-cancer effects. Nucleolar-organizing regions are the ribosomal genes region. We aimed to identify whether Rhamnetin has an effect on cell proliferation and whether AgNOR proteins may be used for the detection of therapeutic benefits of the drugs and new metabolites, which have the potential of being used for cancer treatments. METHODS Twenty-four mice with Ehrlich's ascites carcinoma (EAC) were randomly assigned to three main groups as positive control, and groups 2 and 3 treated intraperitoneally with Rhamnetin (100 µg/kg and 200 µg/kg, respectively). All the animals were sacrificed on day16, 24 h after the last dose; the tumors, which developed at the site of injection were removed. Then, mean AgNOR number and total AgNOR area/nuclear area (TAA/NA) were detected for each mouse. RESULTS Significant differences were detected among all groups for mean AgNOR number (p = 0.000) and TAA/NA ratio (p = 0.000). While the difference between positive control and Rhamnetin (100 µg/kg) group was not significant (p = 0.387), there are significant differences between positive control and Rhamnetin (200 µg/kg) group (p = 0.000) and between Rhamnetin (100 µg/kg) and Rhamnetin (200 µg/kg) groups (p = 0.000) for TAA/NA ratio. CONCLUSION Rhamnetin has an important role in preventing cancer formation. Our study showed that mean AgNOR numbers and TAA/NA values may be used also as biomarkers for evaluating the success rate of the performed therapeutic strategy and accurate dose selection for the management of the disease (Tab. 3, Fig. 3, Ref. 45).
Meltem Ozipek - One of the best experts on this subject based on the ideXlab platform.
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Rhamnetin 3-p-coumaroylrhamninoside from Rhamnus petiolaris.
Phytochemistry, 1994Co-Authors: Meltem Ozipek, Ihsan Calis, M. Ertan, Peter RüediAbstract:Abstract From the berries of Rhamnus petiolaris a new acylated flavonol glycoside was isolated and identified as Rhamnetin 3-O-[34′-O-(p-couma
