Effects of ginkgo flavone aglycone on atherosclerosis based on network pharmacology,molecular docking,and in vitro experiments

Background:Ginkgo flavone aglycones(GA),a Ginkgo(Ginkgo biloba)extract,has been proven to have good biological activity in atherosclerosis(AS)treatment.Moreover,its active compounds and the corresponding mechanism for the treatment of AS remain unclear.Methods:To evaluate and identify the potential pharmacological mechanisms of GA in AS treatment,the program Cytoscape was used to generate network mappings of the GA-AS-potential target gene.GO and KEGG enrichment analyses were performed to further investigate the potential mechanism of AS and the pharmacological properties of GA.A molecular docking approach was utilized to determine the GA components that interact with Akt.In vitro experiments were carried out to identify the anti-atherosclerotic effects of GA by targeting Akt.Results:Network pharmacological research determined that the active components of GA(quercetin,kaempferol,and isorhamnetin)correlated with AS target genes such as AKT1,EGFR,SRC,ESR1,PTGS2,MMP9,KDR,GSK3B,APP,and MMP2,respectively.GO enrichment and KEGG analysis showed that PI3K-Akt signaling may play an important role in GA treatment.Molecular docking experiments indicated that quercetin,kaempferol,and isorhamnetin integrate into the binding pockets of the most potentially beneficial GA-AS target protein(Akt).Consequently,cell experiments were conducted to support the anti-atherosclerotic activity of GA on AS by inhibiting the phosphorylation of AKT1 and its downstream signaling molecules,which regulated the proliferation of HASMCs.Conclusion:Our results detailed GA's active ingredients,potential targets,and molecular basis against AS.GA may exert anti-atherosclerotic effects by suppressing Akt phosphorylation and inhibiting the proliferation of HASMCs.It also proposed a viable approach to determining the scientific foundation and therapeutic mechanism of Chinese herbal medicine extracts in disease therapy.

Isorhamnetin protects porcine oocytes from zearalenone-induced reproductive toxicity through the PI3K/Akt signaling pathway

Background Zearalenone(ZEA)widely exists in moldy grains,which seriously destroys the fertility of females.Isorhamnetin,a natural flavonoid,has extensive of pharmacological activities.However,the beneficial effect and the underlying molecular mechanism of isorhamnetin involvement in ZEA-induced porcine oocyte damage have not been investigated.Methods Oocytes were treated with different concentrations of ZEA(3,5,8 and 10μmol/L)and isorhamnetin(5,10,20 and 30μmol/L)for 44 h at 39℃.ZEA(5μmol/L)and isorhamnetin(10μmol/L)were selected for subsequent studies.Polar body exclusion rate,apoptosis rate and apoptosis related proteins,ROS levels and SOD2 protein,mitochondrial membrane potential and distribution,endoplasmic reticulum distribution and proteins expression,and PI3K,Akt and p-Akt proteins expression of oocytes were detected.In addition,the effect of PI3K antagonist(LY294002)on oocyte nuclear maturation and apoptosis were used to determine the involvement of PI3K/Akt signaling pathway.Results Our findings showed that ZEA exposure damaged oocytes and isorhamnetin therapy restored the developmental capability of porcine oocytes.Isorhamnetin promoted polar body extrusion rate to rescue ZEA-induced meiotic arrest in porcine oocytes.Isorhamnetin alleviated ZEA-induced oxidative stress by stimulating SOD2 protein expression and inhibiting ROS production.Moreover,isorhamnetin enhanced normal mitochondrial distribution and mitochondrial membrane potential to prevent mitochondrial dysfunction induced by ZEA.Changing the expression of endoplasmic reticulum stress-related marker proteins(CHOP,GRP78)and the distribution rate of normal endoplasmic reticulum showed that isorhamnetin relieved ZEA-caused endoplasmic reticulum stress.Mechanistically,isorhamnetin decreased Bax/Bcl-2 protein expression and inhibited ZEA-induced apoptosis through PI3K/Akt signaling pathway.Conclusions Collectively,these results suggest that isorhamnetin protects oocytes from ZEA-caused damage through PI3K/Akt signaling pathway,which enhances meiotic maturation and mitochondrial function,and inhibits early apoptosis,oxidative stress and endoplasmic reticulum stress in porcine oocytes.Our study provides a new strategy for solving the reproductive toxicity induced by ZEA and treating woman infertility.

Umbilical cord-derived mesenchymal stem cells preconditioned with isorhamnetin:potential therapy for burn wounds

BACKGROUND Impaired wound healing can be associated with different pathological states.Burn wounds are the most common and detrimental injuries and remain a major health issue worldwide.Mesenchymal stem cells(MSCs)possess the ability to regenerate tissues by secreting factors involved in promoting cell migration,proliferation and differentiation,while suppressing immune reactions.Preconditioning of MSCs with small molecules having cytoprotective properties can enhance the potential of these cells for their use in cell-based therapeutics.AIM To enhance the therapeutic potential of MSCs by preconditioning them with isorhamnetin for second degree burn wounds in rats.METHODS Human umbilical cord MSCs(hU-MSCs)were isolated and characterized by surface markers,CD105,vimentin and CD90.For preconditioning,hU-MSCs were treated with isorhamnetin after selection of the optimized concentration(5μmol/L)by cytotoxicity analysis.The migration potential of these MSCs was analyzed by the in vitro scratch assay.The healing potential of normal,and preconditioned hU-MSCs was compared by transplanting these MSCs in a rat model of a second degree burn wound.Normal,and preconditioned MSCs(IH+MSCs)were transplanted after 72 h of burn injury and observed for 2 wk.Histological and gene expression analyses were performed on day 7 and 14 after cell transplantation to determine complete wound healing.RESULTS The scratch assay analysis showed a significant reduction in the scratch area in the case of IH+MSCs compared to the normal untreated MSCs at 24 h,while complete closure of the scratch area was observed at 48 h.Histological analysis showed reduced inflammation,completely remodeled epidermis and dermis without scar formation and regeneration of hair follicles in the group that received IH+MSCs.Gene expression analysis was time dependent and more pronounced in the case of IH+MSCs.Interleukin(IL)-1β,IL-6 and Bcl-2 associated X genes showed significant downregulation,while transforming growth factorβ,vascular endothelial growth factor,Bcl-2 and matrix metallopeptidase 9 showed significant upregulation compared to the burn wound,showing increased angiogenesis and reduced inflammation and apoptosis.CONCLUSION Preconditioning of hU-MSCs with isorhamnetin decreases wound progression by reducing inflammation,and improving tissue architecture and wound healing.The study outcome is expected to lead to an improved cell-based therapeutic approach for burn wounds.

Mechanisms of saffron in treatment of atherosclerosis based on network pharmacology

Objective:To explore the main pathways and possible mechanisms of saffron anti-atherosclerosis(AS)using network pharmacology.Methods:The active ingredients and target proteins of the drug were obtained from the TCMSP database,and the gene names corresponding to the target proteins were queried using the Uniprot database to obtain human targets regulated by saffron.Human targets of AS were obtained from DisGeNET database and previous literature.The target gene of saffron was intersected with the target gene of AS to obtain the target gene of saffron for AS.With the help of Cytoscape 3.7.2 software,a saffron active ingredient-potential target,saffron active ingredient-AS disease target interaction network was constructed,and the core targets of saffron's role in AS disease were screened out through evaluation of network topological characteristics such as degree;The ClueGo plug-in in Cytoscape 3.7.2 software was used to analyze GO biological processes and KEGG metabolic pathways of targets.Results:With the drug-like property≥0.18 as the limiting condition and previous literature search and screening,22 compounds were obtained.A total of 106 saffron-regulated target proteins and 117 AS targets were obtained.The intersections were obtained to obtain 26 saffron targets for AS.According to the degree of drug-candidate component-AS candidate target network,the main effective components of saffron anti-AS were crocetin,isorhamnetin and quercetin.26 gene targets were analyzed by KEGG enrichment using the ClueGo plug-in in Cytoscape 3.7.2 software to obtain pathways related to saffron treatment of AS.Using the KEGG database and consulting previous literature,a schematic diagram of the related pathways of saffron anti-AS was obtained.Conclusion:The anti-AS of saffron may be mainly caused by crocetin,isorhamnetin and quercetin in saffron to exert anti-inflammatory and inhibit angiogenesis effects,thereby achieving anti-AS effect.

Effect of Different Isorhamnetin of Different Density Cultured Rat C6 Glioma Cells in Vitro

Objective To explore the influence of different concentrations of isorhamnetin on C6 glioma cell morphology.Methods Set the blank control group,blank solvent control group and reagent group of four concentration,the growth of cells were observed under microscope;MTT assay was used to test the effect of isorhamnetin on cultured C6 glioma cells,as well as calculate the cell inhibition rate and survival rate;flow cytometry was used to check the detection peak and detection rate of Isorhamnetin group and negative control apoptosis group,and analyzed the relationship between different concentrations of isorhamnetin and C6 glioma cell apoptosis rate;total protein was extracted from cells,and used Western blotting to detected total AKT protein and Ser473 AKT protein loci in cells;used SD rats to construct brain glioma model,feed isorhamnetin plain to them for five days,and then used HPLC to detect plasma,liver,brain tissue content.Results Under the observation of inverted microscope and image analysis,after using Isorhamnetin,tumor cells appear apoptosis and necrosis change.Display with different Isorhamnetin MTT colorimetric method shows that the higher the concentration of added Isorhamnetin,the worse the growth rate of C6 glioma cells in vitro,and the higher the Inhibitory rate,the lower survival rate.The flow cytometric detection shows the C6 glioma cells which is added 40 ug/ul Isorhamnetin have the highest rate of apoptosis.After adding 80μg/μl concentration of the isorhamnetin,C6 glioma cells have the lowest survival rate.Western blot test shows the AKT protein and Ser473 total site AKT protein density is in reverse proportion to the increase of the concentration of the isorhamnetin.High performance liquid chromatographic method has determined that there are isorhamnetin in both the rat plasma and brain tissue,which shows that the plasma and tissue all have different isorhamnetin distribution,and isorhamnetin mainly exist in the brain tissue.Conclusion Low concentration of isorhamnetin can induce apoptosis of C6 glioma cells,and high concentration of isorhamnetin can lead to apoptosis and necrosis of C6 glioma cells in vitro,which has obvious inhibitory effect on the growth of glioma cells,and the mechanism is closely related to PI3K/AKT pathway,and in SD rat brain glioma model,the high performance liquid chromatography was used to detect the content of plasma and brain tissue,which indicated the isorhamnetin has target in brain tissue,which provided experimental evidence for the development and utilization of isorhamnetin in mice.

Isorhamnetin Downregulates MMP2 and MMP9 to Inhibit Development of Rheumatoid Arthritis through SRC/ERK/CREB Pathway

Objective To investigate the effect of isorhamnetin on the pathology of rheumatoid arthritis(RA).Methods Tumor necrosis factor(TNF)-α-induced fibroblast-like synoviocytes(FLS)was exposed to additional isorhamnetin(10,20 and 40µmol/L).Overexpression vectors for matrix metalloproteinase-2(MMP2)or MMP9 or SRC were transfected to explore their roles in isorhamnetin-mediated RA-FLS function.RA-FLS viability,migration,and invasion were evaluated.Moreover,a collagen-induced arthritis(CIA)rat model was established.Rats were randomly divided to sham,CIA,low-,medium-,and high-dosage groups using a random number table(n=5 in each group)and administed with normal saline or additional isorhamnetin[2,10,and 20 mg/(kg·day)]for 4 weeks,respectively.Arthritis index was calculated and synovial tissue inflammation was determined in CIA rats.The levels of MMP2,MMP9,TNF-α,interleukin-6(IL-6),and IL-1β,as well as the phosphorylation levels of SRC,extracellular regulated kinase(ERK),and cyclic adenosine monophosphate response element-binding(CREB),were detected in RA-FLS and synovial tissue.Molecular docking was also used to analyze the binding of isorhamnetin to SRC.Results In in vitro studies,isorhamnetin inhibited RA-FLS viability,migration and invasion(P<0.05).Isorhamnetin downregulated the levels of MMP2,MMP9,TNF-α,IL-6,and IL-1βin RA-FLS(P<0.05).The overexpression of either MMP2 or MMP9 reversed isorhamnetin-inhibited RA-FLS migration and invasion,as well as the levels of TNF-α,IL-6,and IL-1β(P<0.05).Furthermore,isorhamnetin bound to SRC and reduced the phosphorylation of SRC,ERK,and CREB(P<0.05).SRC overexpression reversed the inhibitory effect of isorhamnetin on RA-FLS viability,migration and invasion,as well as the negative regulation of MMP2 and MMP9(P<0.05).In in vivo studies,isorhamnetin decreased arthritis index scores(P<0.05)and alleviated synovial inflammation.Isorhamnetin reduced the levels of MMP2,MMP9,TNF-α,IL-6,and IL-1β,as well as the phosphorylation of SRC,ERK,and CREB in synovial tissue(P<0.05).Notably,the inhibitory effect of isorhamnetin was more pronounced at higher concentrations(P<0.05).Conclusion Isorhamnetin exhibited anti-RA effects through modulating SRC/ERK/CREB and MMP2/MMP9 signaling pathways,suggesting that isorhamnetin may be a potential therapeutic agent for RA.

Targeting colorectal cancer using dietary flavonols

Colorectal cancer is among the well-known forms of cancer and a prominent cause of cancer demises worldwide.In vitro experiments reinforced by animal studies,as well as epidemiological studies of human colorectal cancer propose that the growth of this disease can be moderated by eating aspects.Dietary intake including green vegetables and fruits may result in the reduction of colon cancer chances.The finding suggests that the combinations of dietary nutrients may deliver additive or synergistic effects and might be a powerful method to avoid or eradicate colon cancer beginning and/or development.Flavonols are one of the most widespread dietary nutrients of the polyphenols-flavonoids and major constituent of Allium and Brassicaceae vegetables.Flavonols present in vegetables of Allium and Brassicaceae family are kaempferol,myricetin,quercetin,and isorhamnetin.These flavonols are claimed to have antiproliferative activity in vivo and in vitro against colorectal cancer.The objective of this review is to summarize the role of flavonols obtained from dietary sources in the prevention and treatment of colorectal cancer.

苦参根中化学成分及其体外抗肿瘤活性研究

目的研究苦参Sophora flavescens根的化学成分及其体外抗肿瘤活性。方法利用大孔树脂柱色谱、硅胶柱色谱、ODS柱色谱及半制备型HPLC等进行分离纯化,结合理化性质及波谱数据鉴定化合物的结构;评估了从苦参根提取物中分离得到的11个化合物对人乳腺鳞状癌HCC1806细胞,人乳腺癌MCF-7细胞,宫颈癌HeLa细胞,肺癌A549、H1299和H460细胞和人肝癌HepG2细胞的体外抑制活性。结果从苦参根70%乙醇提取物中分离得到17个化合物,分别鉴定为8-(3,3-dimethylallyl)isorhamnetin(1)、6-lavandulyl-7,4-dimethoxy-5,2-dihydroxylflavanone(2)、sophoraflavanone B(3)、5-methyl-sophoraflavanone B(4)、苦参酮(5)、苦参醇U(6)、去甲脱水淫羊藿黄素(7)、槐果碱(8)、9α-羟基槐果碱(9)、槐胺碱(10)、臭豆碱(11)、胡椒酸(12)、1-(4-ethylphenyl)-1,2-ethanediol(13)、丁香酸(14)、1,2,4-苯三酚(15)、阿魏酸(16)、羟苄基酒石酸(17)。其中化合物5对H1299和H460细胞的体外半数抑制浓度(median inhibition concentration,IC50)分别为(22.6±1.2)、(13.6±0.5)μmol/L,其抑制效果强于阳性药顺铂。此外,化合物4对A549细胞和化合物5对MCF-7细胞的抑制效果与阳性药相当。结论化合物1为新的天然产物,化合物2、12~15首次从该属中分离得到;化合物5对H1299细胞和H460细胞具有较好的抑制活性。苦参中的异戊烯基黄酮在抗肿瘤药物开发与应用上有良好的发展前景。

Acid Hydrolytic Method for Determination of Ginkgo Biloba Total Flavonoids in Rat Plasma by HPLC for Pharmacokinetic Studies

A simple, reliable, economical method was developed using HPLC with a diode-array detector for determination of total flavonoids in plasma after introvenous administration of ginkgo biloba extract. The method simultaneously detects quercetin, kaempferol, and isorhamnetin after acid hydrolysis and recalcula- tion. The hydrolysis and extraction conditions were optimized in an orthogonal test. The specificity was tested by comparing the retention time, UV spectra, and peak purity indices with standards. The detection limits were 20 ng/mL for quercetin, 20 ng/mL for kaempferol, and 50 ng/mL for isorhamnetin. The calibration curve ranges were 75-2400, 71-2280, and 70-2240 ng/mL. The pharmacokinetic characteristics of ginkgo biloba flavonoids after venous administration of 50 mg/kg ginkgo biloba extract to rats were analyzed using a two-compartment model. The initial plasma concentration was 171.22 μg/mL. The half-life of flavonoids in the first compartment （distribution） was 0.07 h and at the second compartment （elimination） was 4.51 h, while the AUC（0-∞） was 1711.06 Iag-min/mL. The apparent volume of distribution was 0.11 L/kg. The total body clearance is 10.52 mL/（min.kg）. The result shows the method is suitable for pharmacokinetic studies.

Isorhamnetin protects zearalenone-induced damage via the PI3K/Akt signaling pathway in porcine ovarian granulosa cells

Zearalenone(ZEA)is widely derived from moldy cereal grain,which has adverse effects on animal reproduction.In particular,pigs are more sensitive to ZEA-induced toxicity than other animals.Isorhamnetin has extensive pharmacological activity.However,the role of isorhamnetin in ZEA-induced cytotoxicity remains unclear.This study was designed to investigate the therapeutic effect of isorhamnetin on ZEA-induced damage in porcine ovarian granulosa cells and elucidate its molecular mechanism.Two experiments were conducted,where a minimum of 3 biological replicates were used for each treatment.In Exp.1,ovarian granulosa cells were treated with different concentrations of isorhamnetin(1,5,10,20 and 30μmol/L)and ZEA(0,10,30,60,90 and 120μmol/L)for 24 h.Our results indicated that 60μmol/L ZEA(half-maximal inhibitory concentration value)and 20μmol/L isorhamnetin(the most effective concentration against ZEA-induced cytotoxicity)were optimum concentrations.In Exp.2,ovarian granulosa cells were treated with isorhamnetin(20μmol/L)for 2 h,before treatment with ZEA(60μmol/L)for 24 h.Apoptosis,endoplasmic reticulum stress,oxidative stress,proliferation and hormone secretion of ovarian granulosa cells were detected.Our findings showed that isorhamnetin suppressed(P<0.05)ZEA-induced apoptosis by altering mitochondrial membrane potential and apoptosis-related proteins(B-cell lymphoma-2[Bcl-2],Bcl2-associated x[Bax]and cleaved caspase-3[C-Casp3]).Changes in intracellular Ca2+levels and C/EBP homologous protein(CHOP),recombinant activating transcription factor 6(ATF6),glucose regulated protein78 k D(GRP78)indicated that isorhamnetin rescued(P<0.05)ZEA-induced endoplasmic reticulum stress.Furthermore,isorhamnetin prevented(P<0.05)ZEA-induced oxidative stress via the mitogen-activated protein kinase(P38)signaling pathway.Mechanistically,isorhamnetin stimulated(P<0.05)the expression of proliferating cell nuclear antigen(PCNA)and cyclin D,thereby increasing the ratio of S phase cells in response to ZEAinduced apoptosis via phosphatidylinositol 3 kinase/protein kinase B(PI3K/Akt)signaling pathway.Isorhamnetin also recovered(P<0.05)ZEA-induced steroidogenesis disorder by regulating steroidogenic enzyme gene and proteins(follicle-stimulating hormone receptor[FSHR]and cytochrome P450 family 19subfamily a member 1[CYP19A1]).Collectively,these findings show that isorhamnetin protects ovarian granulosa cells from ZEA-induced damage,which promotes proliferation,alleviates apoptosis,endoplasmic reticulum stress,oxidative stress,and steroidogenesis disorder.