Breast cancer is the leading cause of death among women worldwide.Chemoprevention and chemotherapy play beneficial roles in reducing the incidence and mortality of cancer.Epidemiological and experimental studies showe...Breast cancer is the leading cause of death among women worldwide.Chemoprevention and chemotherapy play beneficial roles in reducing the incidence and mortality of cancer.Epidemiological and experimental studies showed that naturally-occurring antioxidants present in the diet may act as anticancer agents.Identifying the abnormalities of cellular energy metabolism facilitates early detection and management of breast cancer.The present study evaluated the effect of tangeretin on cellular metabolic energy fluxes in 7,12-dimethylbenz（a）anthracene（DMBA）-induced proliferative breast cancer.The results showed that the activities of glycolytic enzymes significantly increased in mammary tissues of DMBA-induced breast cancer bearing rats.The gluconeogenic tricarboxylic acid（TCA） cycle and respiratory chain enzyme activities significantly decreased in breast cancer-bearing rats.In addition,proliferating cell nuclear antigen（PCNA） was highly expressed in breast cancer tissues.However,the activities of glycolytic enzymes were significantly normalized in the tangeretin pre- and post-treated rats and the TCA cycle and respiratory chain enzyme activities were significantly increased in tangeretin treated rats.Furthermore,tangeretin down-regulated PCNA expression on breast cancerbearing rats.Our study demonstrates that tangeretin specifically regulates cellular metabolic energy fluxes in DMBA-induced breast cancer-bearing rats.展开更多
Food allergy has become a worldwide problem. To find an effective way to reduce the allergic effect of allergen is an interesting topic. In this work, the interaction between ovalbumin（OVA） and tangeretin was studie...Food allergy has become a worldwide problem. To find an effective way to reduce the allergic effect of allergen is an interesting topic. In this work, the interaction between ovalbumin（OVA） and tangeretin was studied by means of spectroscopy, molecular docking calculation and animal experiment. As the results show, static quenching of fluorescence intensity happened due to the interaction between OVA and tangeretin. Binding constants, binding sites, and thermometric parameters were obtained. The conformation changing of OVA occurred due to the interaction between it and tangeretin. The molecular docking calculation results show that the epitopes Arginine 84（ARG84）, Leucine 87（LEU87）, Asparagine 88（ASN88）, Serine 103（SER103）, Arginine 104（ARG104）, Leucine 124（LEUI24）, Arginine 126（ARG126）, Glycine 127（GLY127）, Glycine 128（GLY128） and Tryptohan 148（TRP148） of OVA were occupied by tangeretin after the docking, which means tangeretin may have some inhibition effects. As the results of animal experiments, the amount of IgE and lung tissue sections of female BALB/c mice in different groups show that tangeretin with different concentrations has better effects than dexamethasone. In conclusion, the tangeretin may have the effects to reduce the allergic effects of OVA via occupying the IgE-binding epitopes of OVA.展开更多
Flavonoids are polyphenolic secondary metabolites that function as signaling molecules,allopathic compounds,phytoalexins,detoxifying agents and antimicrobial defensive compounds in plants.Blast caused by the fungus Ma...Flavonoids are polyphenolic secondary metabolites that function as signaling molecules,allopathic compounds,phytoalexins,detoxifying agents and antimicrobial defensive compounds in plants.Blast caused by the fungus Magnaporthe oryzae is a serious disease affecting rice cultivation.In this study,we revealed that a natural flavonoid,tangeretin,substantially delays the formation of M.oryzae appressoria and blocks the development of blast lesions on rice plants.Our data suggest that tangeretin has antioxidant activity that interferes with conidial cell death/ferroptosis,which is critical for M.oryzae pathogenicity.Tangeretin showed a ferroptosis inhibition efficacy comparable to the well-established liproxstatin-1.Furthermore,overexpression of the NADPH oxidases NOX1 or NOX2 significantly decreased sensitivity toward tangeretin treatment,suggesting Nox-mediated lipid peroxidation as a possible target for tangeretin in regulating redox signaling and ferroptosis in M.oryzae.Our nursery and field tests showed that application of tangeretin can effectively mitigate overall disease symptoms and prevent leaf blast.Our study reveals the plant-derived fungal ferroptosis inhibitor tangeretin as a potential and novel antifungal agrochemical for the sustainable prevention of the devastating blast disease in important cereal crops.展开更多
The fruit peel of Citrus species(Chenpi),particularly those of mandarin oranges,is a useful source of food and medicine in China.Flavonoids from the citrus fruit peel are mainly polymethoxyflavones(PMFs),of which nobi...The fruit peel of Citrus species(Chenpi),particularly those of mandarin oranges,is a useful source of food and medicine in China.Flavonoids from the citrus fruit peel are mainly polymethoxyflavones(PMFs),of which nobiletin and tangeretin are the most abundant components.In the present review,we summarized the cytotoxic activities of these two PMFs to breast cancer cells.Studies have reported that these two compounds inhibit the growth of breast cancer cells by inducing apoptosis,cytostatic cell death and cell cycle arrest,or by inhibiting cell proliferation,metastasis and tumour angiogenesis,depending on the molecular subtypes of breast cancer.In vitro and in vivo cytotoxic activities involve different molecular targets and signalling pathways.Analyses on the structure-activity relationship(SAR)of nobiletin and tangeretin have shown that the presence of a methoxy group at C8 and a hydroxyl group at C3 or C5 are essential for anti-proliferative activity.Some future perspectives and research needs are suggested.Sources of information are from Pub Med,Pub Med Central,Science Direct,Google Scholar,J-Stage,Pub Chem and CNKI using keyword search.展开更多
目的:建立一测多评法同时测定陈皮中6个黄酮类成分的含量。方法:采用OSAKA CAPCELL PAK C18色谱柱(250 mm×4.6 mm, 5μm),流动相为乙腈-0.1%甲酸溶液,梯度洗脱;流速为1.0 mL·min^(-1),柱温为30℃,检测波长为330 nm。以橙皮苷...目的:建立一测多评法同时测定陈皮中6个黄酮类成分的含量。方法:采用OSAKA CAPCELL PAK C18色谱柱(250 mm×4.6 mm, 5μm),流动相为乙腈-0.1%甲酸溶液,梯度洗脱;流速为1.0 mL·min^(-1),柱温为30℃,检测波长为330 nm。以橙皮苷为内参物,计算橙皮苷与芸香柚皮苷、香蜂草苷、川陈皮素、3,5,6,7,8,3′,4′-七甲氧基黄酮、橘皮素之间的相对校正因子,分别采用一测多评法和外标法对15批陈皮中6个黄酮类成分的含量进行测定并比较结果。结果:6种成分在各自范围内线性关系良好(r≥0.999 9);平均加样回收率99.95%~102.97%,RSD 0.81%~2.03%。一测多评法与外标法的含量测定结果无显著性差异(P>0.05)。结论:本法可对陈皮的质量控制和评价提供科学参考。展开更多
基金financial support from the University Grants Commission,New Delhi,in the form of UGC-BSR Research Fellowship under the UGC-SAP-DRS-III programme is gratefully acknowledged
文摘Breast cancer is the leading cause of death among women worldwide.Chemoprevention and chemotherapy play beneficial roles in reducing the incidence and mortality of cancer.Epidemiological and experimental studies showed that naturally-occurring antioxidants present in the diet may act as anticancer agents.Identifying the abnormalities of cellular energy metabolism facilitates early detection and management of breast cancer.The present study evaluated the effect of tangeretin on cellular metabolic energy fluxes in 7,12-dimethylbenz（a）anthracene（DMBA）-induced proliferative breast cancer.The results showed that the activities of glycolytic enzymes significantly increased in mammary tissues of DMBA-induced breast cancer bearing rats.The gluconeogenic tricarboxylic acid（TCA） cycle and respiratory chain enzyme activities significantly decreased in breast cancer-bearing rats.In addition,proliferating cell nuclear antigen（PCNA） was highly expressed in breast cancer tissues.However,the activities of glycolytic enzymes were significantly normalized in the tangeretin pre- and post-treated rats and the TCA cycle and respiratory chain enzyme activities were significantly increased in tangeretin treated rats.Furthermore,tangeretin down-regulated PCNA expression on breast cancerbearing rats.Our study demonstrates that tangeretin specifically regulates cellular metabolic energy fluxes in DMBA-induced breast cancer-bearing rats.
基金Supported by the National Natural Science Foundation of China（No.31201295） and the Ministry of Education Doctoral Fund, China（No.20120061120116）.
文摘Food allergy has become a worldwide problem. To find an effective way to reduce the allergic effect of allergen is an interesting topic. In this work, the interaction between ovalbumin（OVA） and tangeretin was studied by means of spectroscopy, molecular docking calculation and animal experiment. As the results show, static quenching of fluorescence intensity happened due to the interaction between OVA and tangeretin. Binding constants, binding sites, and thermometric parameters were obtained. The conformation changing of OVA occurred due to the interaction between it and tangeretin. The molecular docking calculation results show that the epitopes Arginine 84（ARG84）, Leucine 87（LEU87）, Asparagine 88（ASN88）, Serine 103（SER103）, Arginine 104（ARG104）, Leucine 124（LEUI24）, Arginine 126（ARG126）, Glycine 127（GLY127）, Glycine 128（GLY128） and Tryptohan 148（TRP148） of OVA were occupied by tangeretin after the docking, which means tangeretin may have some inhibition effects. As the results of animal experiments, the amount of IgE and lung tissue sections of female BALB/c mice in different groups show that tangeretin with different concentrations has better effects than dexamethasone. In conclusion, the tangeretin may have the effects to reduce the allergic effects of OVA via occupying the IgE-binding epitopes of OVA.
基金supported by the National Natural Science Foundation of China(32022070)Key Realm R&D Program of Guangdong Province(2020B0202090001)+1 种基金China Postdoctoral Science Foundation(2020M682723)by Temasek Life Sciences Laboratory(Singapore)。
文摘Flavonoids are polyphenolic secondary metabolites that function as signaling molecules,allopathic compounds,phytoalexins,detoxifying agents and antimicrobial defensive compounds in plants.Blast caused by the fungus Magnaporthe oryzae is a serious disease affecting rice cultivation.In this study,we revealed that a natural flavonoid,tangeretin,substantially delays the formation of M.oryzae appressoria and blocks the development of blast lesions on rice plants.Our data suggest that tangeretin has antioxidant activity that interferes with conidial cell death/ferroptosis,which is critical for M.oryzae pathogenicity.Tangeretin showed a ferroptosis inhibition efficacy comparable to the well-established liproxstatin-1.Furthermore,overexpression of the NADPH oxidases NOX1 or NOX2 significantly decreased sensitivity toward tangeretin treatment,suggesting Nox-mediated lipid peroxidation as a possible target for tangeretin in regulating redox signaling and ferroptosis in M.oryzae.Our nursery and field tests showed that application of tangeretin can effectively mitigate overall disease symptoms and prevent leaf blast.Our study reveals the plant-derived fungal ferroptosis inhibitor tangeretin as a potential and novel antifungal agrochemical for the sustainable prevention of the devastating blast disease in important cereal crops.
文摘The fruit peel of Citrus species(Chenpi),particularly those of mandarin oranges,is a useful source of food and medicine in China.Flavonoids from the citrus fruit peel are mainly polymethoxyflavones(PMFs),of which nobiletin and tangeretin are the most abundant components.In the present review,we summarized the cytotoxic activities of these two PMFs to breast cancer cells.Studies have reported that these two compounds inhibit the growth of breast cancer cells by inducing apoptosis,cytostatic cell death and cell cycle arrest,or by inhibiting cell proliferation,metastasis and tumour angiogenesis,depending on the molecular subtypes of breast cancer.In vitro and in vivo cytotoxic activities involve different molecular targets and signalling pathways.Analyses on the structure-activity relationship(SAR)of nobiletin and tangeretin have shown that the presence of a methoxy group at C8 and a hydroxyl group at C3 or C5 are essential for anti-proliferative activity.Some future perspectives and research needs are suggested.Sources of information are from Pub Med,Pub Med Central,Science Direct,Google Scholar,J-Stage,Pub Chem and CNKI using keyword search.
