Tangeretin inhibits tumor stemness of non-small cell lung cancer by regulating PI3K/AKT/mTOR signaling pathway / 中国胸心血管外科临床杂志

@#Objective    To study the effect of Tangeretin on non-small cell lung cancer (NSCLC) and the tumor stemness, and to find the molecular mechanism of its effect. Methods    We used cell counting and cell cloning experiments to study the effect of Tangeretin on the proliferation of NSCLC cells in vitro. The effect of Tangeretin on the invasion of NSCLC cells was detected by transwell assay. We detected the effect of Tangeretin on the proliferation of NSCLC cells in vivo by nude mouse tumor-bearing experiment. The effect of Tangeretin on tumor stemness of NSCLC cells was detected by self-renew assay, and CD133 and Nanog protein expressions. The expressions of PI3K/AKT/mTOR signaling pathway-related proteins were detected by Western blotting (WB). Results    Tangeretin had a good inhibitory effect on the proliferation of NSCLC cells in vivo and in vitro. Cell counting experiment, clonal formation experiment and nude mouse tumor-bearing experiment showed that Tangeretin could inhibit the proliferation activity, clonal formation ability, and tumor size of NSCLC cells in vivo. Self-renew experiments showed that Tangeretin could inhibit the self-renew ability of NSCLC cells. WB experiments showed that Tangeretin inhibited the expressions of tumor stemness markers CD133 and Nanog in NSCLC cells. Tangeretin could inhibit the activation of PI3K/AKT/mTOR signaling pathway-related proteins in NSCLC cells, and the activation of PI3K/AKT/mTOR signaling pathway could partially remit the inhibitory  effect of Tangeretin on tumor stemness of NSCLC cells. Conclusion    Tangeretin can inhibit the tumor stemness of NSCLC cells, which may be related to the regulation of PI3K/AKT/mTOR signaling pathway.

Role of tangeretin on autophagy in human gastric cancer AGS cells and its mechanism / 中国药理学通报

Aim To investigate the effect of tangeretin on autophagy of human gastric cancer AGS cells and its molecular mechanisms. Methods Western blot was used to detect the effect of tangeretin on expression of LC3, p62 and Akt phosphorylation, and the effects of autophagy inhibitor CQ and activator Rapa on tangere-tin-regulated autophagy. Annexin V/PI double staining was used to quantitatively detect the effect of CQ on apoptosis of cells induced by iangeretin. Results 24h after treatment, tangeretin enhanced the expression of LC3 II protein (P < 0. 05 , P < 0. 01) and p62 (P < 0. 05) in a dose-dependent manner. 48 h after treatment, tangeretin enhanced the expression of p62 protein in a dose-dependent manner (P < 0. 05, P < 0. 01) , and had no significant effect on expression of LC3II protein. At 24 h and 48 h, the expression of LC3II and p62 increased significantly in CQ + Tan group compared with that of Tan group (P < 0. 01). Compared with Tan group, the expression of LC3II and p62 protein decreased in Rapa + Tan group, and there was a statistical difference (P < 0. 05). The apoptotic rate of AGS cells in CQ + Tan group was significantly higher than that in Tan group (P <0. 01). The phosphorylation levels of Akt protein were reduced by tan-gerin for 24 and 48 h in a dose-dependent manner (P <0. 05 , P < 0. 01). Conclusions Tangeretin may promote cell apoptosis by inhibiting the autophagic flux in human gastric cancer AGS cells. Akt phosphorylation might be involved in the autophagy and apoptosis.

Simultaneous quantitative determination of nine active compounds from Aurantii Fructus by HPLC / 中草药

Objective: To establish an HPLC method for simultaneous determination of 7-hydroxycoumarin, narirutin, naringin, hesperidin, neohesperidin, nobiletin, 3,5,6,7,8,(3,4)-heptamethoxyflavone, tangeretin, and auraptene from Aurantii Fructus, determinate and compare the content of various chemical components from Aurantii Fructus with different perimeters. Methods: The HPLC system consisted of a diamon C18 (250 mm × 4.6 mm, 5 μm), the mobile phase was methanol (A)-water (adjusted pH 3.0 with phosphorous acid). The gradient elution conditions: 0-25 min, 30%-50% A; 25-35 min, 50%-70% A; 35-40 min, 70%-75% A; 40-55 min, 75%-100% A. The flow rate was 1.0 mL/min and the column temperature was 30 ℃. The detection wavelength was 320 nm and the injection volume was 20 μL. Results: The calibration curves of 7-hydroxycoumarin, narirutin, naringin, hesperidin, neohesperidin, 3,5,6,7,8,(3,4)-heptamethoxyflavone, nobiletin, tangeretin, and auraptene had good linear relationship in the ranges of 0.002 18-0.07 μg (r = 0.999 8), 0.021 8-0.70 μg (r = 0.999 9), 0.242 5-7.76 μg (r = 0.999 8), 0.024 38-0.78 μg (r = 0.999 4), 0.523 76-16.76 μg (r = 0.999 3), 0.003 13-0.10 μg (r = 0.999 3), 0.004 13-0.132 μg (r = 0.999 6), 0.002 75-0.088 μg (r = 0.999 6), and 0.000 93-0.03 μg (r = 0.999 3); And the average recoveries (n = 6) of the nine components were 98.50%, 98.80%, 99.51%, 98.43%, 99.64%, 99.21%, 100.03%, 98.75%, and 101.11%, respectively. Conclusion: This method can be applied to determinating the components from Aurantii Fructus, including 7-hydroxycoumarin and 3,5,6,7,8,(3,4)-heptamethoxyflavone, etc.

The research progress of anti-tumor effect of polymethoxyflavonoids / 中国药理学通报

Tumor is a disease with high mortality rate,which seriously threatens the human life and health.To study the antitumor effect,sensitization and anti-drug-resistant action of effective ingredients extracted from traditional Chinese medicine or natural medicine is a hotspot.Polymethoxyflavone is a class of flavonoids with strong anti-tumor activity found in recent years.In this paper,the research progress on anti-tumor action and its mechanisms of polymethoxyflavonoids is reviewed.

Tangeretin has anti-asthmatic effects via regulating PI3K and Notch signaling and modulating Th1/Th2/Th17 cytokine balance in neonatal asthmatic mice

Asthma is a chronic allergic disease characterized by airway inflammation, airway hyper-responsiveness (AHR), and mucus hypersecretion. T-lymphocytes are involved in the pathogenesis of asthma, mediating airway inflammatory reactions by secreting cytokines. The phosphoinositide 3-kinase (PI3K) and Notch signaling pathways are associated with T cell signaling, proliferation, and differentiation, and are important in the progression of asthma. Thus, compounds that can modulate T cell proliferation and function may be of clinical value. Here, we assessed the effects of tangeretin, a plant-derived flavonoid, in experimental asthma. BALB/c mice at postnatal day (P) 12 were challenged with ovalbumin (OVA). Separate groups of mice (n=18/group) were administered tangeretin at 25 or 50 mg/kg body weight by oral gavage. Dexamethasone was used as a positive control. Tangeretin treatment reduced inflammatory cell infiltration in bronchoalveolar lavage fluid (BALF) and also restored the normal histology of lung tissues. OVA-specific IgE levels in serum and BALF were reduced. AHR, as determined by airway resistance and lung compliance, was normalized. Flow cytometry analyses revealed a reduced Th17 cell population. Tangeretin reduced the levels of Th2 and Th17 cytokines and raised IFN-γ levels. PI3K signaling was inhibited. The expressions of the Notch 1 receptor and its ligands Jagged 1 and 2 were downregulated by tangeretin. Our findings support the possible use of tangeretin for treating allergic asthma.

Effects of tangeretin on growth and invasion of human non-small-cell lung cancer cells / 中国病理生理杂志

[ ABSTRACT] AIM: To study the influences of tangeretin ( TGN) on the growth and invasion of non-small-cell lung cancer ( NSCLC) cells, and to explore the molecular mechanisms.METHODS: The A549 cells were treated with different concentrations of TGN in vitro.The relative cell activity was determined by MTT assay.The apoptotic rate was an-alyzed by flow cytometry with Annexin V-FITC/PI staining.The number of the invasive cells was measured by Transwell as-say.The mRNA expression of MMP-2 and MMP-9 was detected by RT-PCR, and the protein levels of Ki67, Cyt C, caspase-3, cleaved caspase-3, MMP-2, MMP-9, Akt, p-Akt and p-PI3K were determined by Western blotting analysis. RESULTS:TGN inhibited the proliferation of A549 cells in a dose-dependent manner ( P<0.05) along with the low ex-pression level of proliferation biomarker Ki67.TGN up-regulated the protein levels of Cyt C, caspase-3 and cleaved caspase-3 (P<0.01) and promoted the apoptosis of A549 cells in a dose-dependent manner.Moreover, TGN down-regu-lated the invasion-related molecules MMP-2 and MMP-9 at the mRNA and protein levels, and the number of invasive cells reduced with the increase in the concentration of TGN.The protein levels of p-Akt and p-PI3K in the A549 cells was re-duced (P<0.05), and no difference of the cell viability in the cells treated with different concentrations of TGN was ob-served after blocking PI3K/Akt signaling pathway using LY294002.CONCLUSION: TGN inhibits the growth and inva-sion of A549 cells and promotes the cell apoptosis by potentially inhibiting PI3K/Akt signaling pathway activation.There-fore, this study will provide a new target for the prevention and control of NSCLC.

Composition of Flavonoids and Antioxidative Activity from Juice of Jeju Native Citrus Fruits during Maturation

This study aims to evaluate the changes of flavonoid contents and antioxidants activity of Jeju native citrus fruits juice according to the harvest date. Flavonoids such as quercatagetin, narirutin, hesperidin and neohesperidin were contained most plentifully in the juice of Jigak (Citrus aur- antium) by 573.73 mg/100 mL, Sadoogam (C. pseudogulgul) by 393.99 mg /100 mL, Soyooja by 29.63 mg/100 mL and Jigak (C. aurantium) by 201.23 mg/100 mL in the late August, respectively. The highest contents of nob-iletin, sinensetin and tangeretin among polymethoxyflavones were found in the juice of Hongkyool (C. tachibana) by 7.39 mg/100 mL, 2.24 mg/100 mL, 0.63 mg/100 mL in the late August, respectively. 3,5,6,7,8,3',4'- Heptamet- hoxyflavone recorded the highest amount in Punkyool (C. tangerina) by 0.27 mg/100 mL in the late August, but the other polymethoxyflavones including 3',4',7,8-tetramethoxyflavone, 3',4'-dimethoxyflavone, 4'-methoxyflavone, 5,6,7,3',4',5'-hexamethoxyflavone, scutellarein tetramethylether were observed only trace amount in all the citrus fruits. Flavonoid contents in the citrus fruit juices were the highest during early maturation and decreased rapidly while ripening. Total polyphenol contents were the highest in the late August and decreased with ripening. However from the late December, the contents were increased again. Antioxidant activities of the fruits were evaluated as electron donating ability and were the lowest in the late September and increased with the fruit ripening. These results suggest that quercetagetin among all the flavonoids was most plentiful in Jigak and Dangyooja (C. grandis), so that the fruits could be used for industrial material of flavonoids and antioxidant agents.