Liver cancer is the fourth cause of cancer-related deaths and the primary cause of death in patients with compensated cirrhosis.In recent years,the role of traditional Chinese medicine in the treatment of liver cancer...Liver cancer is the fourth cause of cancer-related deaths and the primary cause of death in patients with compensated cirrhosis.In recent years,the role of traditional Chinese medicine in the treatment of liver cancer has attracted more and more attention and recognition.Luteolin(LUT)and glycyrrhetinic(GA)are natural compounds extracted from Chinese herbal medicine.LUT exhibits various biological activity including anti-inflammatory,antibacterial,antiviral,anti-tumor,and neuroprotective effects.GA significantly inhibits the growth and metastasis of cancer cells.However,the low water solubility of both compounds hinders their clinical applications.In this study,rod-shaped nanoparticles(NPs)self-assembled from LUT and GA were designed to enhance drug solubility and tumor-targeting capability.We verified that the assembly mechanism of the NPs was π-π stacking.These NPs significantly inhibited the proliferation of liver cancer cells while had no significant effect on normal liver cells.In a mouse model of liver cancer,these NPs demonstrated superior tumor-targeting ability due to the enhanced permeability and retention effect,and the affinity of GA for liver cancer cells,resulting in better therapeutic efficacy with lower systemic toxicity.Results of network pharmacology analysis showed that LUT and GA respectively targeted estrogen receptor 1(ESR1)protein and cyclin-dependent kinase 1(CDK1)protein to corporately induce tumor cell cycle arrest,which induced the inhibition of tumor cell proliferation.In conclusion,this study provides a novel reference for the treatment of liver cancer.展开更多
Luteolin is a natural flavonoid compound exists in various fruits and vegetables.Recent studies have indicated that luteolin has variety pharmacological effects,including a wide range of antidepressant properties.Here...Luteolin is a natural flavonoid compound exists in various fruits and vegetables.Recent studies have indicated that luteolin has variety pharmacological effects,including a wide range of antidepressant properties.Here,we systematically review the preclinical studies and limited clinical evidence on the antidepressant and neuroprotective effects of luteolin to fully explore its antidepressant power.Network pharmacology and molecular docking analyses contribute to a better understanding of the preclinical models of depression and antidepressant properties of luteolin.Seventeen preclinical studies were included that combined network pharmacology and molecular docking analyses to clarify the antidepressant mechanism of luteolin and its antidepressant targets.The antidepressant effects of luteolin may involve promoting intracellular noradrenaline(NE)uptake;inhibiting 5-hydroxytryptamine(5-HT)reuptake;upregulating the expression of synaptophysin,postsynaptic density protein 95,brain-derived neurotrophic factor,B cell lymphoma protein-2,superoxide dismutase,and glutathione S-transferase;and decreasing the expression of malondialdehyde,caspase-3,and amyloid-beta peptides.The antidepressant effects of luteolin are mediated by various mechanisms,including anti-oxidative stress,anti-apoptosis,anti-inflammation,anti-endoplasmic reticulum stress,dopamine transport,synaptic protection,hypothalamic-pituitary-adrenal axis regulation,and 5-HT metabolism.Additionally,we identified insulin-like growth factor 1 receptor(IGF1R),AKT serine/threonine kinase 1(AKT1),prostaglandin-endoperoxide synthase 2(PTGS2),estrogen receptor alpha(ESR1),and epidermal growth factor receptor(EGFR)as potential targets,luteolin has an ideal affinity for these targets,suggesting that it may play a positive role in depression through multiple targets,mechanisms,and pathways.However,the clinical efficacy of luteolin and its potential direct targets must be confirmed in further multicenter clinical case-control and molecular targeting studies.展开更多
Hyperuricemia(HUA)refers to a condition where fasting serum uric acid levels exceed 420μmol/L in men and 350μmol/L in women,affecting 17.4%of China’s general population,showing increasing prevalence among younger i...Hyperuricemia(HUA)refers to a condition where fasting serum uric acid levels exceed 420μmol/L in men and 350μmol/L in women,affecting 17.4%of China’s general population,showing increasing prevalence among younger individuals.Luteolin,a common flavonoid compound,exhibits multiple biological effects,including inhibition of tumor proliferation and inflammatory responses.It also suppresses the activity of urate transporter 1(URAT1),promoting uric acid excretion.This study is the first to integrate network toxicology and network pharmacology approaches to systematically analyze the multi-target mechanisms of adenine-induced HUA and luteolin-treated HUA,with molecular docking validation of interaction targets.We constructed compound-pathway-intersection gene networks and a dual-group PPI network to analyze the mechanisms of adenine-induced HUA and luteolin-treated HUA.The dual-group PPI network identified 7 shared targets,namely XDH,PYGL,IL10,PPARG,TNF,VEGFA,and MAOA,involving core intersecting pathways such as purine-xanthine metabolism and insulin resistance.Luteolin may activate PPARG to regulate inflammation and uric acid excretion modules in the adenine network.GO-KEGG analysis indicates that intersection genes for adenine pathogenesis involve diverse biological processes,cellular components,and molecular functions,with core target KEGG analysis revealing 15 signaling pathways.Luteolin’s therapeutic targets are associated with more entries,and its core target KEGG analysis identified 46 signaling pathways.Molecular docking shows TNF,PPARG,and PYGL bind to both luteolin and adenine with negative binding energies,and luteolin’s binding energies are all below 5 kJ/mol,confirming stable binding.Luteolin’s anti-HUA mechanism is characterized by inhibition of production,promotion of excretion,anti-inflammation and metabolic regulation,but interactions with gut microbiota metabolites require further study.展开更多
During the development of diet-induced obesity,the change of energy matebolism is closely related to the function of the circadian clock in mammals.Luteolin(LU),one of the most common natural flavonoids riched in many...During the development of diet-induced obesity,the change of energy matebolism is closely related to the function of the circadian clock in mammals.Luteolin(LU),one of the most common natural flavonoids riched in many edible plants,can ameliorate obesity by activating adipose tissue browning,but its effect on circadian clock in this process remains poorly understood.Here we found that dietary LU improved circadian misalignment of energy expenditure in high-fat diet(HFD)-fed wild-type(WT)mice.Moreover,dietary LU efficiently elevated uncoupling protein 1 levels in adipose tissue during the dark period,which was similar to the LU-increased hepatic PER2 expressions.Hepatic peroxisome proliferators-activated receptorsα(PPARα)/recombinant retinoid X receptorα(RXRα)/fibroblast growth factor 21(FGF21)pathway was rhythmically elevated by dietary LU in HFD-fed WT mice,whereas the promotion was inhibited in Per2^(-/-)mice.Meanwhile,Per2 deletion abolished the effects of dietary LU on adipose tissue browning in HFD-fed mice.Further,LU treatment directly activated PPARα/RXRα/FGF21 signaling in primary cultured hepatocytes from WT mice rather than Per2^(-/-)mice.Taken together,the deletion of the core clock component Per2 impedes LUinduced adipose tissue browning through weakening PPARα/RXRα/FGF21 pathway in mice,providing a new insight into the interplay of energy metabolism and circadian clock for the anti-obesity activity of LU.展开更多
A sensitive RP-HPLC-DAD method has been developed and validated for the determination of luteolin and acteoside in the herb ofSiphonostegia chinensis Benth. （Siphonostegiae Herba）. Separation was achieved on an Agil...A sensitive RP-HPLC-DAD method has been developed and validated for the determination of luteolin and acteoside in the herb ofSiphonostegia chinensis Benth. （Siphonostegiae Herba）. Separation was achieved on an Agilent Zorbax SB-Aq C18 column （250 mm×4.6 mm, 5 μm） using a gradient elution with mobile phases of 0.05% phosphoric acid aqueous solution （A） and methanol （B）. The assay was carried out at a flow rate of 1.0 mL/min with detection at 310 nm and 350 nm. Luteolin and acteoside showed good linearity in the ranges of 0.0341-0.8172 mg/mL （r2 = 0.9999） and 0.0708-2.832 mg/mL （r2 = 0.9999） with average recoveries of 102.7% and 98.3%, respectively. The contents of luteolin and acteoside varied greatly in 15 samples from different habitats. This is the first report on the quantitative determination of acteoside in Siphonostegiae Herba.展开更多
Objective:To obtain Iuteolin and apigenin rich fraction from the ethanolic extract of Cynodon dactylon(L.)(C.dactylon) Pers and evaluate the fraction's cytotoxicity and anti-Chikungunya potential using Vero cells....Objective:To obtain Iuteolin and apigenin rich fraction from the ethanolic extract of Cynodon dactylon(L.)(C.dactylon) Pers and evaluate the fraction's cytotoxicity and anti-Chikungunya potential using Vero cells.Methods:The ethanolic extract of C.dactylon was subjected to silica gel column chromatography to obtain anti-chikungunya virus(CHIKV) fraction.Reverse phase-HPLC and GC-MS studies were carried out to identily the major phytochemicals in the fraction using phylochemical standards.Cytotoxicity and the potential of the fraction against CHIKV were evaluated in vitro using Vero cells.Reduction in viral replication was assessed by reverse transcriptase-polymerase chain reaction(RT-PCR) after treating the viral infected Vero cells with the fraction.Results:Reverse Phase-HPLC and GC-MS studies confirmed the presence of flavonoids,luteolin and apigenin as major phytochemicals in the anti-CHIKV ethanolic fraction of C.dactylon- The fraction was found to exhibit potent viral inhibitory activity(about 98%) at the concentration of 50 μg/mL as observed by reduction in cytopathic effect,and the cytotoxic concentration of the fraction was found to be 250 μg/mL.RT-PCR analyses indicated that the reduction in viral mRNA synthesis in fraction treated infected cells was much higher than the viral infected control cells.Conclusions:Luteolin and apigenin rich ethanolic fraction from C.dactylon can be utilized as a potential therapeutic agent against CHIKV infection as the fraction does not show cytotoxicity while inhibiting the virus.展开更多
Luteolin is an active ingredient found early from Fofium perillae and Flos Ionicerae, and has a specific inhibition on phosphodiesterase 4 （PDE4） activity in vitro. Researches show luteolin has pharmacological effec...Luteolin is an active ingredient found early from Fofium perillae and Flos Ionicerae, and has a specific inhibition on phosphodiesterase 4 （PDE4） activity in vitro. Researches show luteolin has pharmacological effects of anti-inflammation, anti-anaphylaxis, antitumor, antioxidant, protection of nervous system and so on, and has mainly been used for the treatment of respiratory inflammatory diseases, cancer and cardiovascular disease in clinic. PDE4, specific to hydrolyze cyclic AMP （cAMP）, is considered to be a new anti-inflammatory target due to the decisive role on cAMP signal in inflammatory cells such as neutrophils. In order to explore the anti-inflammatory mechanism, we further studied the effects of luteolin on the activity and expression of PDE4, the expression of lymphocyte function-associated antigen-1 （LFA-1） and macrophage-1 （MAC-l） in neutrophils, and the adhesion of neutrophils and endothelial cells. The results showed that luteolin had a dose-dependent inhibition on both bare PDE4 activity and PDE4 in cultured neutrophils, and had an obviously promotive effect on gene expressions of PDE4A, 4B and 4D in later period. Luteolin had a significant inhibitory effect on neutrophils adhesion and LFA-1 expression in early stage, and had no obvious effect on MAC-1 expression. Therefore, luteolin can inhibit LFA-1 expression of neutrophils, then inhibit the adhesion of neutrophils and endothelial cells, and the mechanism is at least related with the inhibition of PDE4 activity.展开更多
Studies have shown that the natural flavonoid luteolin has neurotrophic activity. In this study, we investigated the effect of luteolin in a mouse model of Down syndrome. Ts65 Dn mice, which are frequently used as a m...Studies have shown that the natural flavonoid luteolin has neurotrophic activity. In this study, we investigated the effect of luteolin in a mouse model of Down syndrome. Ts65 Dn mice, which are frequently used as a model of Down syndrome, were intraperitoneally injected with 10 mg/kg luteolin for 4 consecutive weeks starting at 12 weeks of age. The Morris water maze test was used to evaluate learning and memory abilities, and the novel object recognition test was used to assess recognition memory. Immunohistochemistry was performed for the neural stem cell marker nestin, the astrocyte marker glial fibrillary acidic protein, the immature neuron marker DCX, the mature neuron marker NeuN, and the cell proliferation marker Ki67 in the hippocampal dentate gyrus. Nissl staining was used to observe changes in morphology and to quantify cells in the dentate gyrus. Western blot assay was used to analyze the protein levels of brain-derived neurotrophic factor(BDNF) and phospho-extracellular signal-regulated kinase 1/2(p-ERK1/2) in the hippocampus. Luteolin improved learning and memory abilities as well as novel object recognition ability, and enhanced the proliferation of neurons in the hippocampal dentate gyrus. Furthermore, luteolin increased expression of nestin and glial fibrillary acidic protein, increased the number of DCX^+ neurons in the granular layer and NeuN^+ neurons in the subgranular region of the dentate gyrus, and increased the protein levels of BDNF and p-ERK1/2 in the hippocampus. Our findings show that luteolin improves behavioral performance and promotes hippocampal neurogenesis in Ts65 Dn mice. Moreover, these effects might be associated with the activation of the BDNF/ERK1/2 pathway.展开更多
OBJECTIVE: To focus a new chemoprevention approach that uses nanotechnology to deliver luteolin to human breast cancer cells(MCF-7), and its underlying mechanism.METHODS: Water-soluble copolymer-encapsulated nanoparti...OBJECTIVE: To focus a new chemoprevention approach that uses nanotechnology to deliver luteolin to human breast cancer cells(MCF-7), and its underlying mechanism.METHODS: Water-soluble copolymer-encapsulated nanoparticle-luteolin(CENL) was formulated using the hydrophobic drug luteolin. The ability to load and release he anticancer drug into/from the synthesized hyperbranched polyester was evaluated by high-performance liquid chromatography.The successful synthesis of CENL was supported by analytical techniques including fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, gel permeation chromatography,and dynamic light scattering. Cell viability was measured using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide color method. Reactive oxygen species(ROS) were measured using a dichlorofluorescein probe and intracellular calcium(Cai2+) was evaluated with a flu3-AM probe.RESULTS: The results showed that the drug delivery system is stable and that the loading capacity is high. Treatment with nanoparticles containing luteolin and free luteolin resulted in cell death in breast cancer cells at high concentrations (IC50(33 ± 4) and(48 ± 6) μM, respectively)At high concentrations,CENL reduced cell viability and increased ROS and Cai2+ production.CONCLUSION: Our results demonstrate that CENL has potential for human breast cancer treatment.展开更多
Elevated uric acid causes direct injury to pancreatic β-cells. In this study, we examined the effects of luteolin, an important antioxidant, on uric acid-induced β-cell dysfunction. We first evaluated the effect of ...Elevated uric acid causes direct injury to pancreatic β-cells. In this study, we examined the effects of luteolin, an important antioxidant, on uric acid-induced β-cell dysfunction. We first evaluated the effect of luteolin on nitric oxide （NO） formation in uric acid-stimulated Min6 cells using the Griess method. Next, we performed transient transfection and reporter assays to measure transcriptional activity of nuclear factor （NF）-κB. Western blotting assays were also performed to assess the effect of luteolin on the expression of MafA and inducible NO synthase （iNOS） in uric acid-treated cells. Finally, we evaluated the effect of luteolin on uric acidinduced inhibition of glucose-stimulated insulin secretion （GSIS） in Min6 cells and freshly isolated mouse pancreatic islets. We found that luteolin significantly inhibited uric acid-induced NO production, which was well correlated with reduced expression of iNOS mRNA and protein. Furthermore, decreased activity of NF-κB was implicated in inhibition by luteolin of increased iNOS expression induced by uric acid. Besides, luteolin significantly increased MafA expression in Min6 cells exposed to uric acid, which was reversed by overexpression of iNOS. Moreover, luteolin prevented uric acidinduced inhibition of GSIS in both Min6 cells and mouse islets. In conclusion, luteolin protects pancreatic β-cells from uric acid-induced dysfunction and may confer benefit on the protection of pancreatic β-cells in hyperuricemiaassociated diabetes.展开更多
Luteolin is neuroprotective for retinal ganglion cells and retinal pigment epithelial cells after oxidative injury,whereby it can inhibit microglial neurotoxicity.Therefore,luteolin holds the potential to be useful fo...Luteolin is neuroprotective for retinal ganglion cells and retinal pigment epithelial cells after oxidative injury,whereby it can inhibit microglial neurotoxicity.Therefore,luteolin holds the potential to be useful for treatment of retinal diseases.The purpose of this study was to investigate whether luteolin exhibits neuroprotective effects on rod cells in rd10 mice,a slow photoreceptor-degenerative model of retinitis pigmentosa.Luteolin(100 mg/kg)intraperitoneally injected daily from postnatal day 14(P14)to P25 significantly enhanced the visual performance and retinal light responses of rd10 mice at P25.Moreover,it increased the survival of photoreceptors and improved retinal structure.Mechanistically,luteolin treatment attenuated increases in reactive oxygen species,photoreceptor apoptosis,and reactive gliosis;increased mRNA levels of anti-inflammatory cytokines while lowering that of pro-inflammatory and chemoattractant cytokines;and lowered the ratio of phospho-JNK/JNK.Application of the JNK inhibitor SP600125 exerted a similar protective effect to luteolin,suggesting that luteolin delays photoreceptor degeneration and functional deterioration in rd10 mice through regulation of retinal oxidation and inflammation by inhibiting the JNK pathway.Therefore,luteolin may be useful as a supplementary treatment for retinitis pigmentosa.This study was approved by the Qualified Ethics Committee of Jinan University,China(approval No.IACUC-20181217-02)on December 17,2018.展开更多
This paper proposes luteolin(LUT)as a novel depressant for the flotation-based separation of scheelite and calcite in a sodium oleate(NaOL)system.The suitability of LUT as a calcite depressant is confirmed through mic...This paper proposes luteolin(LUT)as a novel depressant for the flotation-based separation of scheelite and calcite in a sodium oleate(NaOL)system.The suitability of LUT as a calcite depressant is confirmed through micro-flotation testing.At pH=9,with LUT concentration of 50 mg·L^(-1) and NaOL concentration of 50 mg·L^(-1),scheelite recovery reaches 80.3%.Calcite,on the other hand,exhibits a recovery rate of 17.6%,indicating a significant difference in floatability between the two minerals.Subsequently,the surface modifica-tions of scheelite and calcite following LUT treatment are characterized using adsorption capacity testing,Zeta potential analysis,Fourier transform infrared spectroscopy(FT-IR),X-ray photoelectron spectroscopy(XPS),and atomic force microscopy(AFM).The study in-vestigates the selective depressant mechanism of LUT on calcite.Adsorption capacity testing and Zeta potential analysis demonstrate sub-stantial absorption of LUT on the surface of calcite,impeding the further adsorption of sodium oleate,while its impact on scheelite is min-imal.FT-IR and XPS analyses reveal the selective adsorption of LUT onto the surface of calcite,forming strong chemisorption bonds between the hydroxyl group and calcium ions present.AFM directly illustrates the distinct adsorption densities of LUT on the two miner-al types.Consequently,LUT can effectively serve as a depressant for calcite,enabling the successful separation of scheelite and calcite.展开更多
Polyphenols are the main active components of the anti-inflammatory compounds in dandelion,and chlorogenic acid(CGA)is one of the primary polyphenols.However,the molecular mechanism underlying the transcriptional regu...Polyphenols are the main active components of the anti-inflammatory compounds in dandelion,and chlorogenic acid(CGA)is one of the primary polyphenols.However,the molecular mechanism underlying the transcriptional regulation of CGA biosynthesis remains unclear.Hydroxycinnamoyl-CoA:quinate hydroxycinnamoyl transferase(HQT2)is the last rate-limiting enzyme in chlorogenic acid biosynthesis in Taraxacum antungense.Therefore,using the TaHQT2 gene promoter as a probe,a yeast one-hybrid library was performed,and a basic helix-loop-helix(bHLH)transcription factor,TabHLH1,was identified that shared substantial homology with Gynura bicolor DC bHLH1.The TabHLH1 transcript was highly induced by salt stress,and the TabHLH1 protein was localized in the nucleus.CGA and luteolin concentrations in TabHLH1-overexpression transgenic lines were significantly higher than those in the wild type,while CGA and luteolin concentrations in TabHLH1-RNA interference(RNAi)transgenic lines were significantly lower.Quantitative real-time polymerase chain reaction demonstrated that overexpression and RNAi of TabHLH1 in T.antungense significantly affected CGA and luteolin concentrations by upregulating or downregulating CGA and luteolin biosynthesis pathway genes,especially TaHQT2,4-coumarate-CoA ligase(Ta4CL),chalcone isomerase(TaCHI),and flavonoid-3′-hydroxylase(TaF3′H).Dual-luciferase,yeast one-hybrid,and electrophoretic mobility shift assays indicated that TabHLH1 directly bound to the bHLH-binding motifs of proTaHQT2 and proTa4CL.This study suggests that TabHLH1 participates in the regulatory network of CGA and luteolin biosynthesis in T.antungense and might be useful for metabolic engineering to promote plant polyphenol biosynthesis.展开更多
AIM:To investigate the effects of luteolin on apoptosis,the cell cycle,and the expression and secretion of vascular endothelial growth factor(VEGF)in human choroidal melanoma cells(C918 and OCM-1).METHODS:C918 and OCM...AIM:To investigate the effects of luteolin on apoptosis,the cell cycle,and the expression and secretion of vascular endothelial growth factor(VEGF)in human choroidal melanoma cells(C918 and OCM-1).METHODS:C918 and OCM-1 cells cultured in vitro were treated with various concentrations of luteolin(0,5,10,15μmol/L).Cell growth was observed with an inverted microscope,and cell cycle arrest was detected by propidium iodide(PI)staining using flow cytometry.Apoptosis was detected by Hoechst33342 staining,and apoptosis rate was determined by Annexin V-FITC/PI experiments using flow cytometry.The expression of apoptosis-related proteins Bcl-2,Bax and VEGF was analyzed using Western blots.The levels of VEGF secreted by the cells into the supernatant was analyzed using ELISA.RESULTS:After treating with 5 to 15μmol/L luteolin for 48 h,the fusion degree of C918 and OCM-1 cells decreased,and more floating apoptotic cells appeared.Luteolin treatment increased the G0-G1 phase ratio of the C918 and OCM-1 cells,blocked cell cycle progression,and increased the apoptosis rate of the C918 and OCM-1 cells.Western blot showed that luteolin decreased the expression of Bcl-2 and VEGF in the C918 and OCM-1 cells and increased the expression of Bax protein.The ELISA results showed that 10 to 15μmol/L luteolin decreased the cell secretion of VEGF.CONCLUSION:Luteolin may induce apoptosis by regulating the levels of apoptosis-related proteins in C918 and OCM-1 cells.Luteolin can induce cell cycle arrest,decrease the expression of VEGF.展开更多
The present study was conducted to verify the influence of luteolin on apoptosis of Eca109 cells and to further investigate the possible mechanisms underlying its effect on apoptosis.The cells were exposed to differen...The present study was conducted to verify the influence of luteolin on apoptosis of Eca109 cells and to further investigate the possible mechanisms underlying its effect on apoptosis.The cells were exposed to different concentrations of luteolin(0,40,80,120,160,200,240M)for 24,48,and 72 h respectively.The influence of luteolin on proliferation of Eca109 cells was detected using MTT assay.Eca109 cells were then treated with luteolin(0,40,160,240M)for 24 h.The effect of luteolin on cell cycle progression and apoptosis was assayed by using flow cytometry(FCM).Expression of caspase9 and caspase3 mRNA and protein was analyzed by real-time PCR and Western blot respectively.The results showed that luteolin could inhibit the proliferation of Eca109 cells at all concentrations in a time-dependent manner and the relative inhibition rate showed an inverted U-shaped association with the concentration of luteolin.Further,the cell cycle was arrested in the S phase following treatment with luteolin.Apoptosis analysis indicated that luteolin could induce the apoptosis of Eca109 cells across the three concentration groups,which exhibited a trend of first promotional and then inhibitory with the increases in luteolin concentration.The effect of luteolin on the mRNA and protein expression of caspase 9 and caspase3 first manifested as promotion,then inhibition.Therefore,luteolin may serve a role in promoting cell apoptosis by inducing Eca109 cell apoptosis that involves the expression of caspase3,caspase9 mRNA and protein.This study provides theoretical basis for further study and clinical application of luteolin.The specific mechanism has not yet been clarified and the other activation pathways inducing apoptosis need to be further studied.展开更多
OBJECTIVE:To investigate the antitumour efficacy of luteolin on gastric cancer(GC)and study the mechanism underpinning the action.METHODS:Effects of luteolin on cell growth inhibition,apoptosis,and cell cycle arrest i...OBJECTIVE:To investigate the antitumour efficacy of luteolin on gastric cancer(GC)and study the mechanism underpinning the action.METHODS:Effects of luteolin on cell growth inhibition,apoptosis,and cell cycle arrest in MKN45 cells were investigated using the cell counting kit-8 assay.Changes in the mitochondrial membrane potential after luteolin treatment were assessed using 5,5′,6,6’-tetra-chloro-1,1’,3,3’-tetraethy lbenzimidazolcar bocyanineiodi-de(JC-1)staining.To investigate whether apoptotic effect by luteolin is related to the phosphoinositide 3-kinase/v-akt murine thymoma viral oncogene(PI3K/Akt)pathway,cells were additionally treated with LY294002,a PI3K/Akt pathway inhibitor.Moreover,the expressions of apoptosis-related proteins,namely B-cell lymphoma 2(Bcl-2),Bcl-2 associated X protein(Bax),Akt,p-Akt,caspase-3,and cytochrome C,were detected after luteolin treatment.RESULTS:The study revealed that in MKN45 cells,luteolin could inhibit the cell proliferation in a time-and dose-dependent manner;block the cell cycle in the Sphase;induce apoptosis;reduce the mitochondrial membrane potential;increase the expression of Bax,caspase-3,and cytochrome C;and decrease the expression of Bcl-2 and p-Akt.Luteolin might be involved in the PI3K/Akt signalling pathway,indicating that this pathway could be a therapeutic target for GC treatment.CONCLUSION:Luteolin could inhibit the proliferation of GC cells and block the cell cycle in the S-phase.The mechanism of inducing apoptosis in these cells was related to the PI3K/Akt signalling pathway.展开更多
Luteolin （3＇,4＇,5,7-tetrahydroxyflavone） has powerful anti-apoptotic and antioxidant properties. This study aimed to investigate the effects of luteolin on hyperglycemia-mediated apoptosis in the hippocampi of rat...Luteolin （3＇,4＇,5,7-tetrahydroxyflavone） has powerful anti-apoptotic and antioxidant properties. This study aimed to investigate the effects of luteolin on hyperglycemia-mediated apoptosis in the hippocampi of rats with streptozotocin-induced diabetic encephalopathy after injection into the tail veins, and the molecular mechanisms involved. Biochemistry and terminal deoxynucleotidyl transferase mediated dUTP nick end labelling detection results showed that luteolin treatment （given twice daily for 15 days） significantly inhibited hyperglycemia-mediated apoptosis, decreased malondialdehyde levels and increased glutathione levels in the hippocampi of streptozotocin- induced diabetic rats. Western blot analysis revealed that luteolin also inhibited the expression of apoptosis-related factors and cytochrome c release from mitochondria. Luteolin also improved the learning and memory abiJities of rats with diabetic encephalopathy in a water maze test. Further western blot analysis revealed that luteolin treatment facilitated neuronal cell survival through activation of the phosphatidylinositol 3-kinase/Akt signaling pathway, an extracellular signal pathway involved in the suppression of cell apoptosis and promotion of cell survival. These experimental findings indicate that luteolin can inhibit apoptosis of hippocampal nerve cells in rats with diabetic encephalopathy, and that this effect is mediated by an indirect antioxidative effect, the inhibition of activation of apoptosis-related factors and the activation of phosphatidylinositol 3-kinase/Akt signal pathway.展开更多
基金the financial support from Henan Province Natural Science Foundation(No.252300420583)Henan Provincial Science and Technology Research Project(Nos.242102310455,242102310473,242102310517)the Key Project of Science and Technology Research funded by the Henan Provincial Department of Education(No.24A350002)。
文摘Liver cancer is the fourth cause of cancer-related deaths and the primary cause of death in patients with compensated cirrhosis.In recent years,the role of traditional Chinese medicine in the treatment of liver cancer has attracted more and more attention and recognition.Luteolin(LUT)and glycyrrhetinic(GA)are natural compounds extracted from Chinese herbal medicine.LUT exhibits various biological activity including anti-inflammatory,antibacterial,antiviral,anti-tumor,and neuroprotective effects.GA significantly inhibits the growth and metastasis of cancer cells.However,the low water solubility of both compounds hinders their clinical applications.In this study,rod-shaped nanoparticles(NPs)self-assembled from LUT and GA were designed to enhance drug solubility and tumor-targeting capability.We verified that the assembly mechanism of the NPs was π-π stacking.These NPs significantly inhibited the proliferation of liver cancer cells while had no significant effect on normal liver cells.In a mouse model of liver cancer,these NPs demonstrated superior tumor-targeting ability due to the enhanced permeability and retention effect,and the affinity of GA for liver cancer cells,resulting in better therapeutic efficacy with lower systemic toxicity.Results of network pharmacology analysis showed that LUT and GA respectively targeted estrogen receptor 1(ESR1)protein and cyclin-dependent kinase 1(CDK1)protein to corporately induce tumor cell cycle arrest,which induced the inhibition of tumor cell proliferation.In conclusion,this study provides a novel reference for the treatment of liver cancer.
基金supporting by the National Nature Science Foundation of China(Grant No.:82071215)the Outstanding Scientific Fund of Shengjing Hospital,China(Grant No.:202208).
文摘Luteolin is a natural flavonoid compound exists in various fruits and vegetables.Recent studies have indicated that luteolin has variety pharmacological effects,including a wide range of antidepressant properties.Here,we systematically review the preclinical studies and limited clinical evidence on the antidepressant and neuroprotective effects of luteolin to fully explore its antidepressant power.Network pharmacology and molecular docking analyses contribute to a better understanding of the preclinical models of depression and antidepressant properties of luteolin.Seventeen preclinical studies were included that combined network pharmacology and molecular docking analyses to clarify the antidepressant mechanism of luteolin and its antidepressant targets.The antidepressant effects of luteolin may involve promoting intracellular noradrenaline(NE)uptake;inhibiting 5-hydroxytryptamine(5-HT)reuptake;upregulating the expression of synaptophysin,postsynaptic density protein 95,brain-derived neurotrophic factor,B cell lymphoma protein-2,superoxide dismutase,and glutathione S-transferase;and decreasing the expression of malondialdehyde,caspase-3,and amyloid-beta peptides.The antidepressant effects of luteolin are mediated by various mechanisms,including anti-oxidative stress,anti-apoptosis,anti-inflammation,anti-endoplasmic reticulum stress,dopamine transport,synaptic protection,hypothalamic-pituitary-adrenal axis regulation,and 5-HT metabolism.Additionally,we identified insulin-like growth factor 1 receptor(IGF1R),AKT serine/threonine kinase 1(AKT1),prostaglandin-endoperoxide synthase 2(PTGS2),estrogen receptor alpha(ESR1),and epidermal growth factor receptor(EGFR)as potential targets,luteolin has an ideal affinity for these targets,suggesting that it may play a positive role in depression through multiple targets,mechanisms,and pathways.However,the clinical efficacy of luteolin and its potential direct targets must be confirmed in further multicenter clinical case-control and molecular targeting studies.
基金supported by the National College Student Innovation and Entrepreneurship Project.
文摘Hyperuricemia(HUA)refers to a condition where fasting serum uric acid levels exceed 420μmol/L in men and 350μmol/L in women,affecting 17.4%of China’s general population,showing increasing prevalence among younger individuals.Luteolin,a common flavonoid compound,exhibits multiple biological effects,including inhibition of tumor proliferation and inflammatory responses.It also suppresses the activity of urate transporter 1(URAT1),promoting uric acid excretion.This study is the first to integrate network toxicology and network pharmacology approaches to systematically analyze the multi-target mechanisms of adenine-induced HUA and luteolin-treated HUA,with molecular docking validation of interaction targets.We constructed compound-pathway-intersection gene networks and a dual-group PPI network to analyze the mechanisms of adenine-induced HUA and luteolin-treated HUA.The dual-group PPI network identified 7 shared targets,namely XDH,PYGL,IL10,PPARG,TNF,VEGFA,and MAOA,involving core intersecting pathways such as purine-xanthine metabolism and insulin resistance.Luteolin may activate PPARG to regulate inflammation and uric acid excretion modules in the adenine network.GO-KEGG analysis indicates that intersection genes for adenine pathogenesis involve diverse biological processes,cellular components,and molecular functions,with core target KEGG analysis revealing 15 signaling pathways.Luteolin’s therapeutic targets are associated with more entries,and its core target KEGG analysis identified 46 signaling pathways.Molecular docking shows TNF,PPARG,and PYGL bind to both luteolin and adenine with negative binding energies,and luteolin’s binding energies are all below 5 kJ/mol,confirming stable binding.Luteolin’s anti-HUA mechanism is characterized by inhibition of production,promotion of excretion,anti-inflammation and metabolic regulation,but interactions with gut microbiota metabolites require further study.
文摘During the development of diet-induced obesity,the change of energy matebolism is closely related to the function of the circadian clock in mammals.Luteolin(LU),one of the most common natural flavonoids riched in many edible plants,can ameliorate obesity by activating adipose tissue browning,but its effect on circadian clock in this process remains poorly understood.Here we found that dietary LU improved circadian misalignment of energy expenditure in high-fat diet(HFD)-fed wild-type(WT)mice.Moreover,dietary LU efficiently elevated uncoupling protein 1 levels in adipose tissue during the dark period,which was similar to the LU-increased hepatic PER2 expressions.Hepatic peroxisome proliferators-activated receptorsα(PPARα)/recombinant retinoid X receptorα(RXRα)/fibroblast growth factor 21(FGF21)pathway was rhythmically elevated by dietary LU in HFD-fed WT mice,whereas the promotion was inhibited in Per2^(-/-)mice.Meanwhile,Per2 deletion abolished the effects of dietary LU on adipose tissue browning in HFD-fed mice.Further,LU treatment directly activated PPARα/RXRα/FGF21 signaling in primary cultured hepatocytes from WT mice rather than Per2^(-/-)mice.Taken together,the deletion of the core clock component Per2 impedes LUinduced adipose tissue browning through weakening PPARα/RXRα/FGF21 pathway in mice,providing a new insight into the interplay of energy metabolism and circadian clock for the anti-obesity activity of LU.
基金National Key Technology R&D Program "New Drug Innovation" of China (Grant No. 2009ZX 09308-004,2009ZX09311-004,2012ZX09301002-002)
文摘A sensitive RP-HPLC-DAD method has been developed and validated for the determination of luteolin and acteoside in the herb ofSiphonostegia chinensis Benth. （Siphonostegiae Herba）. Separation was achieved on an Agilent Zorbax SB-Aq C18 column （250 mm×4.6 mm, 5 μm） using a gradient elution with mobile phases of 0.05% phosphoric acid aqueous solution （A） and methanol （B）. The assay was carried out at a flow rate of 1.0 mL/min with detection at 310 nm and 350 nm. Luteolin and acteoside showed good linearity in the ranges of 0.0341-0.8172 mg/mL （r2 = 0.9999） and 0.0708-2.832 mg/mL （r2 = 0.9999） with average recoveries of 102.7% and 98.3%, respectively. The contents of luteolin and acteoside varied greatly in 15 samples from different habitats. This is the first report on the quantitative determination of acteoside in Siphonostegiae Herba.
文摘Objective:To obtain Iuteolin and apigenin rich fraction from the ethanolic extract of Cynodon dactylon(L.)(C.dactylon) Pers and evaluate the fraction's cytotoxicity and anti-Chikungunya potential using Vero cells.Methods:The ethanolic extract of C.dactylon was subjected to silica gel column chromatography to obtain anti-chikungunya virus(CHIKV) fraction.Reverse phase-HPLC and GC-MS studies were carried out to identily the major phytochemicals in the fraction using phylochemical standards.Cytotoxicity and the potential of the fraction against CHIKV were evaluated in vitro using Vero cells.Reduction in viral replication was assessed by reverse transcriptase-polymerase chain reaction(RT-PCR) after treating the viral infected Vero cells with the fraction.Results:Reverse Phase-HPLC and GC-MS studies confirmed the presence of flavonoids,luteolin and apigenin as major phytochemicals in the anti-CHIKV ethanolic fraction of C.dactylon- The fraction was found to exhibit potent viral inhibitory activity(about 98%) at the concentration of 50 μg/mL as observed by reduction in cytopathic effect,and the cytotoxic concentration of the fraction was found to be 250 μg/mL.RT-PCR analyses indicated that the reduction in viral mRNA synthesis in fraction treated infected cells was much higher than the viral infected control cells.Conclusions:Luteolin and apigenin rich ethanolic fraction from C.dactylon can be utilized as a potential therapeutic agent against CHIKV infection as the fraction does not show cytotoxicity while inhibiting the virus.
基金financial support of the Beijing Natural Science Foundation, China (6112007)the National Natural Science Foundation of China (31101851)+1 种基金the Funding Project for Academic Human Resources Development in Institutions of Higher Learning under the Jurisdiction of Beijing Municipality, China (PHR201107134)the Comprehensive Reforming Project to promote talents training of Beijing University of Agriculture, China (BNRC&GG201404)
文摘Luteolin is an active ingredient found early from Fofium perillae and Flos Ionicerae, and has a specific inhibition on phosphodiesterase 4 （PDE4） activity in vitro. Researches show luteolin has pharmacological effects of anti-inflammation, anti-anaphylaxis, antitumor, antioxidant, protection of nervous system and so on, and has mainly been used for the treatment of respiratory inflammatory diseases, cancer and cardiovascular disease in clinic. PDE4, specific to hydrolyze cyclic AMP （cAMP）, is considered to be a new anti-inflammatory target due to the decisive role on cAMP signal in inflammatory cells such as neutrophils. In order to explore the anti-inflammatory mechanism, we further studied the effects of luteolin on the activity and expression of PDE4, the expression of lymphocyte function-associated antigen-1 （LFA-1） and macrophage-1 （MAC-l） in neutrophils, and the adhesion of neutrophils and endothelial cells. The results showed that luteolin had a dose-dependent inhibition on both bare PDE4 activity and PDE4 in cultured neutrophils, and had an obviously promotive effect on gene expressions of PDE4A, 4B and 4D in later period. Luteolin had a significant inhibitory effect on neutrophils adhesion and LFA-1 expression in early stage, and had no obvious effect on MAC-1 expression. Therefore, luteolin can inhibit LFA-1 expression of neutrophils, then inhibit the adhesion of neutrophils and endothelial cells, and the mechanism is at least related with the inhibition of PDE4 activity.
基金supported by the Project Funding for the Training of High Level Health Professionals in Changzhou of China,No.2016CZLJ013(to BY)Science and Technology Support Project of Changzhou of China,No.Social Development CE20175021(to BY)Application Basic Research Project of Changzhou of China,No.CJ20160036(to WBZ)
文摘Studies have shown that the natural flavonoid luteolin has neurotrophic activity. In this study, we investigated the effect of luteolin in a mouse model of Down syndrome. Ts65 Dn mice, which are frequently used as a model of Down syndrome, were intraperitoneally injected with 10 mg/kg luteolin for 4 consecutive weeks starting at 12 weeks of age. The Morris water maze test was used to evaluate learning and memory abilities, and the novel object recognition test was used to assess recognition memory. Immunohistochemistry was performed for the neural stem cell marker nestin, the astrocyte marker glial fibrillary acidic protein, the immature neuron marker DCX, the mature neuron marker NeuN, and the cell proliferation marker Ki67 in the hippocampal dentate gyrus. Nissl staining was used to observe changes in morphology and to quantify cells in the dentate gyrus. Western blot assay was used to analyze the protein levels of brain-derived neurotrophic factor(BDNF) and phospho-extracellular signal-regulated kinase 1/2(p-ERK1/2) in the hippocampus. Luteolin improved learning and memory abilities as well as novel object recognition ability, and enhanced the proliferation of neurons in the hippocampal dentate gyrus. Furthermore, luteolin increased expression of nestin and glial fibrillary acidic protein, increased the number of DCX^+ neurons in the granular layer and NeuN^+ neurons in the subgranular region of the dentate gyrus, and increased the protein levels of BDNF and p-ERK1/2 in the hippocampus. Our findings show that luteolin improves behavioral performance and promotes hippocampal neurogenesis in Ts65 Dn mice. Moreover, these effects might be associated with the activation of the BDNF/ERK1/2 pathway.
基金the financial and technical support of Ilam University of Medical Science
文摘OBJECTIVE: To focus a new chemoprevention approach that uses nanotechnology to deliver luteolin to human breast cancer cells(MCF-7), and its underlying mechanism.METHODS: Water-soluble copolymer-encapsulated nanoparticle-luteolin(CENL) was formulated using the hydrophobic drug luteolin. The ability to load and release he anticancer drug into/from the synthesized hyperbranched polyester was evaluated by high-performance liquid chromatography.The successful synthesis of CENL was supported by analytical techniques including fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, gel permeation chromatography,and dynamic light scattering. Cell viability was measured using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide color method. Reactive oxygen species(ROS) were measured using a dichlorofluorescein probe and intracellular calcium(Cai2+) was evaluated with a flu3-AM probe.RESULTS: The results showed that the drug delivery system is stable and that the loading capacity is high. Treatment with nanoparticles containing luteolin and free luteolin resulted in cell death in breast cancer cells at high concentrations (IC50(33 ± 4) and(48 ± 6) μM, respectively)At high concentrations,CENL reduced cell viability and increased ROS and Cai2+ production.CONCLUSION: Our results demonstrate that CENL has potential for human breast cancer treatment.
基金supported by the National Basic Research Program ofChina(2011CB504000,Program 973)the National Natural ScienceFoundation of China(81070656,81171589)the Colleges andUniversities in Jiangsu Province Plans to Graduate Research andInnovation(No.CXZZ12_0562)and Grant(No.100011)from the HealthDepartment of Sichuan Province to D.W
文摘Elevated uric acid causes direct injury to pancreatic β-cells. In this study, we examined the effects of luteolin, an important antioxidant, on uric acid-induced β-cell dysfunction. We first evaluated the effect of luteolin on nitric oxide （NO） formation in uric acid-stimulated Min6 cells using the Griess method. Next, we performed transient transfection and reporter assays to measure transcriptional activity of nuclear factor （NF）-κB. Western blotting assays were also performed to assess the effect of luteolin on the expression of MafA and inducible NO synthase （iNOS） in uric acid-treated cells. Finally, we evaluated the effect of luteolin on uric acidinduced inhibition of glucose-stimulated insulin secretion （GSIS） in Min6 cells and freshly isolated mouse pancreatic islets. We found that luteolin significantly inhibited uric acid-induced NO production, which was well correlated with reduced expression of iNOS mRNA and protein. Furthermore, decreased activity of NF-κB was implicated in inhibition by luteolin of increased iNOS expression induced by uric acid. Besides, luteolin significantly increased MafA expression in Min6 cells exposed to uric acid, which was reversed by overexpression of iNOS. Moreover, luteolin prevented uric acidinduced inhibition of GSIS in both Min6 cells and mouse islets. In conclusion, luteolin protects pancreatic β-cells from uric acid-induced dysfunction and may confer benefit on the protection of pancreatic β-cells in hyperuricemiaassociated diabetes.
基金The work was supported by the National Natural Science Foundation of China,Nos.81470656(to YX),82071372(to AL),82074169(to XSM)Guangdong Grant Key Technologies for Treatment of Brain Disorders’,China,No.2018B030332001(to YX)+3 种基金Ningxia Key Research and Development Program Grant(Yinchuan,Ningxia Hui Autonomous Region,China)(to KFS)Program of Introducing Talents of Discipline to Universities,China,No.B14036(to YX,AL,KFS)Outstanding Scholar Program of Bioland Laboratory(Guangzhou Regenerative Medicine and Health Guangdong Laboratory),No.2018GZR110102002(to KFS,AL)Science and Technology Program of Guangzhou,No.202007030012(to KFS and AL).
文摘Luteolin is neuroprotective for retinal ganglion cells and retinal pigment epithelial cells after oxidative injury,whereby it can inhibit microglial neurotoxicity.Therefore,luteolin holds the potential to be useful for treatment of retinal diseases.The purpose of this study was to investigate whether luteolin exhibits neuroprotective effects on rod cells in rd10 mice,a slow photoreceptor-degenerative model of retinitis pigmentosa.Luteolin(100 mg/kg)intraperitoneally injected daily from postnatal day 14(P14)to P25 significantly enhanced the visual performance and retinal light responses of rd10 mice at P25.Moreover,it increased the survival of photoreceptors and improved retinal structure.Mechanistically,luteolin treatment attenuated increases in reactive oxygen species,photoreceptor apoptosis,and reactive gliosis;increased mRNA levels of anti-inflammatory cytokines while lowering that of pro-inflammatory and chemoattractant cytokines;and lowered the ratio of phospho-JNK/JNK.Application of the JNK inhibitor SP600125 exerted a similar protective effect to luteolin,suggesting that luteolin delays photoreceptor degeneration and functional deterioration in rd10 mice through regulation of retinal oxidation and inflammation by inhibiting the JNK pathway.Therefore,luteolin may be useful as a supplementary treatment for retinitis pigmentosa.This study was approved by the Qualified Ethics Committee of Jinan University,China(approval No.IACUC-20181217-02)on December 17,2018.
基金supported by the National Natural Science Foundation of China (No.52164022).
文摘This paper proposes luteolin(LUT)as a novel depressant for the flotation-based separation of scheelite and calcite in a sodium oleate(NaOL)system.The suitability of LUT as a calcite depressant is confirmed through micro-flotation testing.At pH=9,with LUT concentration of 50 mg·L^(-1) and NaOL concentration of 50 mg·L^(-1),scheelite recovery reaches 80.3%.Calcite,on the other hand,exhibits a recovery rate of 17.6%,indicating a significant difference in floatability between the two minerals.Subsequently,the surface modifica-tions of scheelite and calcite following LUT treatment are characterized using adsorption capacity testing,Zeta potential analysis,Fourier transform infrared spectroscopy(FT-IR),X-ray photoelectron spectroscopy(XPS),and atomic force microscopy(AFM).The study in-vestigates the selective depressant mechanism of LUT on calcite.Adsorption capacity testing and Zeta potential analysis demonstrate sub-stantial absorption of LUT on the surface of calcite,impeding the further adsorption of sodium oleate,while its impact on scheelite is min-imal.FT-IR and XPS analyses reveal the selective adsorption of LUT onto the surface of calcite,forming strong chemisorption bonds between the hydroxyl group and calcium ions present.AFM directly illustrates the distinct adsorption densities of LUT on the two miner-al types.Consequently,LUT can effectively serve as a depressant for calcite,enabling the successful separation of scheelite and calcite.
基金This work was supported by the Zhejiang Provincial Ten Thousand Program for Leading Talents of Science and Technology Innovation[2018R52050]the National Natural Science Fund of China[Grant numbers:82073963,81522049,81703636,31571735,31270007]+1 种基金the Zhejiang Provincial Program for the Cultivation of High-Level Innovative Health Talents,the Research Project of Zhejiang Chinese Medical University(2021JKZDZC06)the Opening Project of Zhejiang Provincial Preponderant and Characteristic Subject of Key University(Traditional Chinese Pharmacology),Zhejiang Chinese Medical University[ZYAOXZD2019006]。
文摘Polyphenols are the main active components of the anti-inflammatory compounds in dandelion,and chlorogenic acid(CGA)is one of the primary polyphenols.However,the molecular mechanism underlying the transcriptional regulation of CGA biosynthesis remains unclear.Hydroxycinnamoyl-CoA:quinate hydroxycinnamoyl transferase(HQT2)is the last rate-limiting enzyme in chlorogenic acid biosynthesis in Taraxacum antungense.Therefore,using the TaHQT2 gene promoter as a probe,a yeast one-hybrid library was performed,and a basic helix-loop-helix(bHLH)transcription factor,TabHLH1,was identified that shared substantial homology with Gynura bicolor DC bHLH1.The TabHLH1 transcript was highly induced by salt stress,and the TabHLH1 protein was localized in the nucleus.CGA and luteolin concentrations in TabHLH1-overexpression transgenic lines were significantly higher than those in the wild type,while CGA and luteolin concentrations in TabHLH1-RNA interference(RNAi)transgenic lines were significantly lower.Quantitative real-time polymerase chain reaction demonstrated that overexpression and RNAi of TabHLH1 in T.antungense significantly affected CGA and luteolin concentrations by upregulating or downregulating CGA and luteolin biosynthesis pathway genes,especially TaHQT2,4-coumarate-CoA ligase(Ta4CL),chalcone isomerase(TaCHI),and flavonoid-3′-hydroxylase(TaF3′H).Dual-luciferase,yeast one-hybrid,and electrophoretic mobility shift assays indicated that TabHLH1 directly bound to the bHLH-binding motifs of proTaHQT2 and proTa4CL.This study suggests that TabHLH1 participates in the regulatory network of CGA and luteolin biosynthesis in T.antungense and might be useful for metabolic engineering to promote plant polyphenol biosynthesis.
文摘AIM:To investigate the effects of luteolin on apoptosis,the cell cycle,and the expression and secretion of vascular endothelial growth factor(VEGF)in human choroidal melanoma cells(C918 and OCM-1).METHODS:C918 and OCM-1 cells cultured in vitro were treated with various concentrations of luteolin(0,5,10,15μmol/L).Cell growth was observed with an inverted microscope,and cell cycle arrest was detected by propidium iodide(PI)staining using flow cytometry.Apoptosis was detected by Hoechst33342 staining,and apoptosis rate was determined by Annexin V-FITC/PI experiments using flow cytometry.The expression of apoptosis-related proteins Bcl-2,Bax and VEGF was analyzed using Western blots.The levels of VEGF secreted by the cells into the supernatant was analyzed using ELISA.RESULTS:After treating with 5 to 15μmol/L luteolin for 48 h,the fusion degree of C918 and OCM-1 cells decreased,and more floating apoptotic cells appeared.Luteolin treatment increased the G0-G1 phase ratio of the C918 and OCM-1 cells,blocked cell cycle progression,and increased the apoptosis rate of the C918 and OCM-1 cells.Western blot showed that luteolin decreased the expression of Bcl-2 and VEGF in the C918 and OCM-1 cells and increased the expression of Bax protein.The ELISA results showed that 10 to 15μmol/L luteolin decreased the cell secretion of VEGF.CONCLUSION:Luteolin may induce apoptosis by regulating the levels of apoptosis-related proteins in C918 and OCM-1 cells.Luteolin can induce cell cycle arrest,decrease the expression of VEGF.
基金Thanks for the support of the National Natural Science Foundation of China(https://isisn.nsfc.gov.cn/egrantindex/funcindex/prjsearch-list,grant nos.:81673147,81372985)he Fundamental Research Funds for the Central Universities(grant no.:2242017K40035)Postgraduate Research&Practice Innovation Program of Jiangsu Province(grant no.:SJCX170070).
文摘The present study was conducted to verify the influence of luteolin on apoptosis of Eca109 cells and to further investigate the possible mechanisms underlying its effect on apoptosis.The cells were exposed to different concentrations of luteolin(0,40,80,120,160,200,240M)for 24,48,and 72 h respectively.The influence of luteolin on proliferation of Eca109 cells was detected using MTT assay.Eca109 cells were then treated with luteolin(0,40,160,240M)for 24 h.The effect of luteolin on cell cycle progression and apoptosis was assayed by using flow cytometry(FCM).Expression of caspase9 and caspase3 mRNA and protein was analyzed by real-time PCR and Western blot respectively.The results showed that luteolin could inhibit the proliferation of Eca109 cells at all concentrations in a time-dependent manner and the relative inhibition rate showed an inverted U-shaped association with the concentration of luteolin.Further,the cell cycle was arrested in the S phase following treatment with luteolin.Apoptosis analysis indicated that luteolin could induce the apoptosis of Eca109 cells across the three concentration groups,which exhibited a trend of first promotional and then inhibitory with the increases in luteolin concentration.The effect of luteolin on the mRNA and protein expression of caspase 9 and caspase3 first manifested as promotion,then inhibition.Therefore,luteolin may serve a role in promoting cell apoptosis by inducing Eca109 cell apoptosis that involves the expression of caspase3,caspase9 mRNA and protein.This study provides theoretical basis for further study and clinical application of luteolin.The specific mechanism has not yet been clarified and the other activation pathways inducing apoptosis need to be further studied.
基金Supported by the National Key R&D Program(No.2017YFC1700605)the National Science and Technology Major Special Project(No.2017ZX09304001)the State Administration of Traditional Chinese Medicine,and the State Clinical Laboratory of Traditional Chinese Medicine(No.JDZX2015068)。
文摘OBJECTIVE:To investigate the antitumour efficacy of luteolin on gastric cancer(GC)and study the mechanism underpinning the action.METHODS:Effects of luteolin on cell growth inhibition,apoptosis,and cell cycle arrest in MKN45 cells were investigated using the cell counting kit-8 assay.Changes in the mitochondrial membrane potential after luteolin treatment were assessed using 5,5′,6,6’-tetra-chloro-1,1’,3,3’-tetraethy lbenzimidazolcar bocyanineiodi-de(JC-1)staining.To investigate whether apoptotic effect by luteolin is related to the phosphoinositide 3-kinase/v-akt murine thymoma viral oncogene(PI3K/Akt)pathway,cells were additionally treated with LY294002,a PI3K/Akt pathway inhibitor.Moreover,the expressions of apoptosis-related proteins,namely B-cell lymphoma 2(Bcl-2),Bcl-2 associated X protein(Bax),Akt,p-Akt,caspase-3,and cytochrome C,were detected after luteolin treatment.RESULTS:The study revealed that in MKN45 cells,luteolin could inhibit the cell proliferation in a time-and dose-dependent manner;block the cell cycle in the Sphase;induce apoptosis;reduce the mitochondrial membrane potential;increase the expression of Bax,caspase-3,and cytochrome C;and decrease the expression of Bcl-2 and p-Akt.Luteolin might be involved in the PI3K/Akt signalling pathway,indicating that this pathway could be a therapeutic target for GC treatment.CONCLUSION:Luteolin could inhibit the proliferation of GC cells and block the cell cycle in the S-phase.The mechanism of inducing apoptosis in these cells was related to the PI3K/Akt signalling pathway.
文摘Luteolin （3＇,4＇,5,7-tetrahydroxyflavone） has powerful anti-apoptotic and antioxidant properties. This study aimed to investigate the effects of luteolin on hyperglycemia-mediated apoptosis in the hippocampi of rats with streptozotocin-induced diabetic encephalopathy after injection into the tail veins, and the molecular mechanisms involved. Biochemistry and terminal deoxynucleotidyl transferase mediated dUTP nick end labelling detection results showed that luteolin treatment （given twice daily for 15 days） significantly inhibited hyperglycemia-mediated apoptosis, decreased malondialdehyde levels and increased glutathione levels in the hippocampi of streptozotocin- induced diabetic rats. Western blot analysis revealed that luteolin also inhibited the expression of apoptosis-related factors and cytochrome c release from mitochondria. Luteolin also improved the learning and memory abiJities of rats with diabetic encephalopathy in a water maze test. Further western blot analysis revealed that luteolin treatment facilitated neuronal cell survival through activation of the phosphatidylinositol 3-kinase/Akt signaling pathway, an extracellular signal pathway involved in the suppression of cell apoptosis and promotion of cell survival. These experimental findings indicate that luteolin can inhibit apoptosis of hippocampal nerve cells in rats with diabetic encephalopathy, and that this effect is mediated by an indirect antioxidative effect, the inhibition of activation of apoptosis-related factors and the activation of phosphatidylinositol 3-kinase/Akt signal pathway.
