OBJECTIVE: To screen the effective antioxidant components in Trichosanthes extract based on the mean value of Deng's correlation degree and assess the antioxidant activity of the identified components. METHOD: High-performance liquid chromatography (HPLC) was used to obtain the fingerprints of Trichosanthes extract, and the clearance rates of DPPH · and O₂^-· by 3, 9 and 27 mg/mL Trichosanthes extract were determined. The antioxidant spectrum effect of Trichosanthes extract was analyzed by calculating the mean value of Deng's correlation degree to screen the effective antioxidant component group. According to the contents of each known components in the antioxidant effective component group, mixed solutions of the components were prepared and tested for their clearance rates of DPPH · and O₂^-·. RESULTS: The 36 common peaks in HPLC fingerprints of Trichosanthes extract showed different degrees of correlation with DPPH · and O₂^-· clearance. The common peaks with a correlation degree greater than the median value included peaks 21, 36, 8, 31, 14, 5, 27, 2, 24, 15, 18, 33, 22, 34, 35, 19, 28 and 25. The 5 components, namely kaempferol (peak 36), isoquercitrin (peak 8), luteolin (peak 31), rutin (peak 5) and apigenin (peak 35), were tentatively identified to constitute the effective antioxidant component group with a mass ratio 3∶2∶2∶ 1∶1 in Trichosanthes extract. The prepared mixed solutions of antioxidant effective component group (6.12, 2.04, and 0.68 μg/mL) showed clearance rates of DPPH · of 65.4%, 64.0% and 61.0%, and clearance rates of O₂^-· of 12.9%, 9.5% and 8.3%, respectively. CONCLUSION We identified the material basis for the antioxidant activity of Trichosanthes and screened the antioxidant effective component group in Trichosanthes extract.
Antioxidants/pharmacology* ; Chromatography, High Pressure Liquid/methods* ; Luteolin ; Plant Extracts/pharmacology* ; Trichosanthes/chemistry*

The aim of this study was to investigate the mechanism of luteolin regulating lipoxygenase pathway against oxygen-glucose deprivation/reperfusion(OGD/R) injury in H9 c2 cardiomyocytes. First, Discovery Studio 2019 was used for the molecular docking of luteolin with three key enzymes including lipoxygenase 5(ALOX5), lipoxygenase 12(ALOX12), and lipoxygenase 15(ALOX15) in lipoxygenase pathway. The docking results showed that luteolin had high docking score and similar functional groups with the original ligand. From this, H9 c2 cardiomyocytes were cultured in vitro, and then the injury model of H9 c2 cardiomyocytes was induced by deprivation of oxygen-glucose for 8 h, and rehabilitation of oxygen-glucose for 12 h. Cell viability was detected by tetrazolium(MTT) colorimetry. H9 c2 cardiomyocytes were observed with a fluorescence inverted microscope, and colorimetry was used to detect the level of lactate dehydrogenase(LDH) in cell supernatant. The results showed that luteolin could significantly protect the morphology of H9 c2 cells, significantly improve the survival rate of H9 c2 cardiomyocytes in OGD/R injury model, reduce the level of LDH in cell supernatant, inhibit cytotoxicity, and maintain the integrity of cell membrane. The inflammatory cytokines interleukin-6(IL-6) and tumor necrosis factor-α(TNF-α) were detected by enzyme-linked immunosorbent assay. Compared with the model group, luteolin can significantly reduce the release of IL-6 and TNF-α. Western blot was employed to detect the protein levels of ALOX5, ALOX12, and ALOX15 in lipoxygenase pathway. After luteolin intervention, the protein levels of ALOX5, ALOX12, and ALOX15 were significantly down-regulated compared with those in model group. These results indicate that luteolin can inhibit the release of IL-6 and TNF-α by restraining the activation of lipoxygenase pathway, thereby playing a protective role in the cardiomyocyte injury model induced by OGD/R.
Apoptosis ; Glucose ; Humans ; Lipoxygenases ; Luteolin/pharmacology* ; Molecular Docking Simulation ; Myocytes, Cardiac ; Oxygen ; Reperfusion Injury ; Signal Transduction

Objective: This study aimed to investigate the effect of exposure to a 900 MHz electromagnetic field (EMF) on the cervical spinal cord (CSC) of rats and the possible protective effect of luteolin (LUT) against CSC tissue damage. Methods: Quantitative data were obtained stereological, biochemical, immunohistochemical, and histopathological techniques. We investigated morphometric value, superoxide dismutase (SOD) level, and the expression of high-mobility group box 1 protein molecules, as well as histological changes. Results: The total number of motor neurons in the EMF group significantly decreased in comparison with that in the control group ( < 0.05). In the EMF + LUT group, we found a significant increase in the total number of motor neurons compared with that in the EMF group ( < 0.05). SOD enzyme activity in the EMF group significantly increased in comparison with that in the control group ( < 0.05). By contrast, the EMF+LUT group exhibited a decrease in SOD level compared with the EMF group ( < 0.05). Conclusion Our results suggested that exposure to EMF could be deleterious to CSC tissues. Furthermore, the protective efficacy of LUT against SC damage might have resulted from the alleviation of oxidative stress caused by EMF.
Animals ; Antioxidants ; pharmacology ; Electromagnetic Fields ; adverse effects ; Luteolin ; pharmacology ; Male ; Rats ; Rats, Wistar ; Spinal Cord ; drug effects ; radiation effects

The purpose of the present study was to investigate the effect of luteolin on the angiogenesis and invasion of breast cancer cells. MTT assay was used to examine breast cancer proliferation. The chick chorioallantoic membrane model was used to assess the angiogenesis effect. Wound healing assay was used to assess cell invasion ability. Western blot was used to analyze Bcl-2, AEG-1 and MMP-2 expression levels. The results showed luteolin inhibited MCF-7 cells proliferation in a dose- and time-dependent manner, and the expression of Bcl-2 protein was decreased. Luteolin had a strong anti-angiogenesis of chick chorioallantoic membrane. After treatment of MCF-7 cells with luteolin at 60 μmol/L for 48 h, migration rate was reduced by 71.07% compared with control (P < 0.01). After treatment of MCF-7 cells with luteolin at 60 μmol/L for 48 h, the expression of AEG-1 and MMP-2 was reduced by 82.34% (P < 0.05) and 85.70% (P < 0.05) respectively, compared with control. In conclusion, the results suggest that luteolin can inhibit the proliferation of breast cancer cells, and suppress the expression of Bcl-2. Furthermore, luteolin has strong anti-angiogenesis of chick chorioallantoic membrane and anti-invasive activity on breast cancer cells, and down-regulates the expression of AEG-1 and MMP-2.
Animals ; Breast Neoplasms ; pathology ; Cell Adhesion Molecules ; metabolism ; Cell Proliferation ; Chickens ; Chorioallantoic Membrane ; drug effects ; Down-Regulation ; Female ; Humans ; Luteolin ; pharmacology ; MCF-7 Cells ; Matrix Metalloproteinase 2 ; metabolism ; Neovascularization, Pathologic ; pathology ; Proto-Oncogene Proteins c-bcl-2 ; metabolism

OBJECTIVETo investigate the effect of luteolin on cell growth and apoptosis of HepG2 cells in vitro.

METHODSCultured HepG2,HL60,A549 and LO2 cells were treated with luteolin for different doses (0 μg/ml,2.5 μg/ml,10 μg/ml and 20 μg/ml) and varied times (0 h,24 h,48 h and 72 h). Cell viability was measured with MTT assay and IC50 was calculated. The reactive oxygen species (ROS) levels in HepG2 cells treated with luteolin for 6 h and 12 h were measured with flow cytometry. Cell apoptosis of HepG2 cells treated with luteolin for 24h was examined with flow cytometry and Annexin V-FITC/PI. Expression levels of apoptosis pathway proteins (p53,ASPP2 and iASPP) in HepG2 cells were detected with western blot and the dose and time-effect was analyzed.

RESULTSLuteolin effectively inhibited tumor cell proliferation in a dose-and time-dependent manner,and the inhibition rates of 20 μg/ml Luteolin for 72 h were 39.34%,62.90%,57.57% and 62.90% to LO2,HepG2, HL60 and A549 cells,respectively. The intracellular ROS level was decreased in HepG2 cells by 13.88% and 41.11% after being treated with luteolin for 6 h and 12 h,respectively. The apoptosis rate of HepG2 cells treated with luteolin for 24 h was 14.43%,and western blot showed that luteolin reduced the expression level of iASPP by 77.07% and up-regulated the expression of p53 by 179.37% and ASPP2 by 725.02% in HepG2 cells treated with luteolin for 12 h.

CONCLUSIONLuteolin has ant-proliferative and pro-apoptotic activity on hepatoma HepG2 cells, which is associated with the altered expression of pro-apoptotic factors and decreased ROS level in HepG2 cells.

Apoptosis ; drug effects ; Hep G2 Cells ; Humans ; Luteolin ; administration & dosage ; pharmacology ; Reactive Oxygen Species ; metabolism

OBJECTIVETo investigate the protective effect of luteolin on isolated rat heart in hypothermic preservation.

METHODSForty male SD rats were randomly divided into 4 groups (n = 10): control group, luteolin low-dose group (7.5 micromol/L), middle-dose group (15 micromol/L) and high dose group (30 micromol/L). Langendorff model of isolated rat heart was used. After 30 min basal perfusion, the hearts were stored in University of Wisconsin solution (UW solution) at 4 degrees C with luteolin (7.5, 15 and 30 micromol/L) or without luteolin for 12 h and followed by 60 min reperfusion. The recovery of cardiac contractile and diastolic function, coronary flow (CF), creatine kinase (CK) leakage in the coronary effluent, myocardial water content were determined. The myocardial ultrastructure was also observed.

RESULTSThe results revealed that luteolin improved the recovery of left ventricular peak systolic pressure and +/- dp/dtmax dose-dependently and increased coronary flow. The leakage of creatine kinase in the coronary effluent was significantly reduced in luteolin-added hearts. Impairment of myocardial ultrastructure after 12 h hypothermic preservation was obviously alleviated in hearts luteolin-added group compared with that in control group. There were no differences between the groups in myocardial water contents.

CONCLUSIONLuteolin as a supplementation in cardiac preservation solution can significantly improve the hypothermic preservation effects on rat heart and have myocardial protection effect, especially in luteolin-added with 30 micromol/L.

Animals ; Cryopreservation ; In Vitro Techniques ; Luteolin ; pharmacology ; Male ; Myocardium ; Organ Preservation ; methods ; Organ Preservation Solutions ; Rats

OBJECTIVETo study luteolin-induced non-small cell lung cancer cell line A549 apoptosis and the molecular mechanism for inhibiting its cycle arrest (G2 stage).

METHODMTT assay showed that luteolin had obvious inhibitory effect on A549 and indicated the half inhibition ratio (IC50). Cell cycle and apoptosis were detected by Hoechst 33258 nuclear staining assay, Annexin V-FITC/PI double staining and flow cytometry. Western blotting assay revealed changes in cycle and apoptosis-related proteins induced by luteolin. Possible molecular mechanism was suggested by Western blotting and immunocytochemistry.

RESULTLuteolin had an obvious growth inhibitory effect on A549 cells, with IC50 of 45.2 micromol x L(-1) at 48 h. Flow cytometry showed A549 cells mainly arrested in G2 stage after being treated by luteolin, with low expressions in cyclin A, p-CDC2 and p-Rb. Hoechst 33258 nuclear staining and Annexin V-FITC/PI double staining showed that the luteolin treatment group showed a significant apoptosis rate than the non-treatment group. Western blotting found luteolin can increase phosphorylation of JNK and decrease that of NF-kappaKB (p65). Immunocytochemistry results revealed luteolin can inhibit TNF-alpha-stimulated p65 from nuclear translocation as a transcription factor and thus promoting cell apoptosis.

CONCLUSIONLuteolin can obviously induce apoptosis of human non-small cell lung cancer cell A549 possibly by increasing phosphorylation of JNK to activate mitochondria apoptosis pathway, while inhibiting NF-kappaB from nuclear translocation as a transcription factor.

Annexin A5 ; metabolism ; Apoptosis ; drug effects ; Blotting, Western ; Carcinoma, Non-Small-Cell Lung ; metabolism ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Humans ; Luteolin ; pharmacology ; NF-kappa B ; metabolism

OBJECTIVETo investigate the effects of luteolin (Chinese Traditional Medicine) on cardiac functions and mitochondrial oxidative stress in streptozotocin (STZ)-induced diabetic rats.

METHODSMale SD rats were randomly divided into a normal control group, a luteolin control group, a diabetic group, and diabetic groups orally administered with a low dose (10 mg/(kg x d)) or a high dose of luteolin (100 mg/ (kg x d)) for eight weeks. The body weight, blood glucose, cardiac functions, left ventricular weight, myocardial collagen and reactive oxygen species (ROS) levels were assayed. The cardiac mitochondrial ROS level, superoxide dismutase (SOD) activity and the mitochondrial swelling were measured.

RESULTSTreatment with luteolin had no effect on the blood glucose but reduced the losing of body weight in diabetic rats. High dose of luteolin markedly reduced the ratio of ventricular weight and body weight, increased the left ventricular develop pressure, and decreased the left ventricular end diastolic pressure in diabetic rats. The myocardial levels of ROS and collagen, the cardiac mitochondrial ROS level, and the mitochondrial swelling in diabetic rats were all markedly reduced by high dose of luteolin. Furthermore, high dose of luteolin significantly increased the mitochondrial SOD activity in diabetic rat hearts.

CONCLUSIONTreatment with luteolin for 8 weeks markedly improves the cardiac function, which may be related to reducing mitochondrial oxidative stress and mitochondrial swelling in diabetic rats.

Animals ; Diabetes Mellitus, Experimental ; metabolism ; physiopathology ; Luteolin ; pharmacology ; Male ; Mitochondria, Heart ; metabolism ; Oxidative Stress ; physiology ; Rats ; Rats, Sprague-Dawley ; Reactive Oxygen Species ; metabolism ; Ventricular Dysfunction ; prevention & control

OBJECTIVELuteolin, a flavone, has considerable neuroprotective effects by its anti-oxidative mechanism. However, it is still unclear whether luteolin can protect neurons against oxygen-glucose deprivation/reperfusion (OGD/R) induced injury.

METHODAfter 2 hours oxygen-glucose deprivation and 24 hours reperfusion treatment in primary cultured hippocampal neurons, the neuron viability, survival rate and apoptosis rate were evaluated by MTT assay, lactate dehydrogenase (LDH) leakage assay and Hoechst staining, respectively. The activity of Na+/K+ -ATPase was examined in cultured neurons or in the hippocampus of SD rats treated by 10 minutes global cerebral ischemia and followed 24 hours reperfusion.

RESULTTreatment by OGD/R markedly reduced neuronal viability, increased LDH leakage rate and increased apoptosis rate. Application of luteolin (10-100 micromol x L(-1)) during OGD inhibited OGD/R induced neuron injury and apoptosis in a dose-dependent manner. Compared to the control group or OGP/R-treated neurons, the activity of Na+/K+ -ATPase was significantly suppressed in global ischemia/reperfusion group or OGD/R-treated neurons. Application of luteolin during ischemia or OGD preserved the Na+/K+ -ATPase activity. Furthermore, inhibition of Na+/K+ -ATPase with ouabain attenuated the protective effect afforded by luteolin.

CONCLUSIONThe data provide the evidence that luteolin has neuroprotective effect against OGD/R induced injury and the protective effect may be associated with its ability to improve Na+/K+ -ATPase activity after OGD/R.

Animals ; Antioxidants ; pharmacology ; Apoptosis ; drug effects ; Cell Hypoxia ; Glucose ; metabolism ; Luteolin ; pharmacology ; Neurons ; drug effects ; enzymology ; metabolism ; pathology ; Neuroprotective Agents ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury ; enzymology ; metabolism ; pathology ; prevention & control ; Sodium-Potassium-Exchanging ATPase ; metabolism

OBJECTIVETo investigate the effect of Luteolin alone or combination with chemotherapentic drugs on the cytoxicity of cancer cells.

METHODSCultured A549, Hela, MCF-7, AGS, MGC-803, Caco2 and HepG2 cells were treated with Luteolin or the combination of Luteolin with other chemotherapeutic agents (Bexarotene, Cisplatin and Bleomycin). Cell viability was measured by MTS assay and IC(50) was calculated.

RESULTSThe IC(50) of Bexarotene to Hela cells was 2 micromol/L, but with the combination of 5 micromol/L of Luteolin that reduced to 0.2 micromol/L. However, the combination of Bexarotene and Luteolin did not show significant benefit in MGC-803, HepG2 cells, Caco2 and MCF-7 cells. The IC(50) of Cisplatin to Hela cells was over 30 micromol/L,but it decreased to 3 micromol/L in the presence of 5 micromol/L Luteolin; Luteolin also sensitized Cisplatin in MGC-803, HepG2 and A549 cells studied. The IC(50) of Bleomycin to Hela cells was over 100 micromol/L, but it was about 1 micromol/L in the presence of 5 micromol/L Luteolin. A549 cells were resistant to Bleomycin with an IC(50) of 100 micromol/L, 10 micromol/L Luteolin greatly enhanced the cytotoxicity of Bleomycin to the cells with the IC(50) of about 10 micromol/L. The inhibitions of MGC-803, HepG2, A549 and AGS cells didn't change by combination of Luteolin.

CONCLUSIONLow concentration of Luteolin has little toxic effect on the cancer cell lines tested in the study, but it can sensitize chemotherapeutic drugs in various cancer cell lines.

Antineoplastic Agents ; pharmacology ; Breast Neoplasms ; pathology ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Drug Synergism ; Humans ; Lung Neoplasms ; pathology ; Luteolin ; pharmacology ; Neoplasms ; pathology