Xanthohumol is one of the principal flavonoids isolated from hops, the inhibitor of diacylglycerol acetyltransferase (DGAT), COX-1 and COX-2, and shows anti-cancer and anti-angiogenic activities.
Calycosin-7-O-β-D-glucoside, a melanin biosynthesis inhibitor, is isolated from the methanol extract of astragalus. IC50 value: 68 μM in inhibition of Tyrosinase Target:In vitro: Calycosin-7-O-β-d-glucoside showed a melanin biosynthesis inhibition zone in a culture plate of Streptomyces bikiniensis. Furthermore, 75.78 μM of calycosin-7-O-β-d-glucoside dramatically decreased 50% of the melanin content on Melan-a cells without any apparent cytotoxicity [1]. Calycosin-7-O-β-D-glucoside was revealed to scavenge NO, inhibit the activities of MMP-2 and MMP-9, and attenuate cell death in the in vitro cultured brain microvascular endothelial cells under OGD condition.In vivo: Calycosin-7-O-β-D-glucoside treatment significantly reduced infarct volume, histological damage and blood–brain barrier permeability in the in vivo MCAO ischemia–reperfusion rat model [2]. To reveal its physiological functions under stress, seedlings with different isoflavonoid levels were established using a phenylalanine ammonia lyase (PAL) enzyme inhibitor, l-α-aminooxy-β-phenylpropionic acid (AOPP). The results showed that the significant promotion of antioxidant capacity in this species might be associated with the remarkable accumulation of Calycosin-7-O-β-D-glucoside after cold pretreatment. The results provided the first evidence that a type of isoflavonoid, Calycosin-7-O-β-D-glucoside, might play a very important role against freezing stress in vivo [3].
Syringaldehyde is a polyphenolic compound belonging to the group of flavonoids and is found in different plant species like Manihot esculenta and Magnolia officinalis[1]. Syringaldehyde moderately inhibits COX-2 activity with an IC50 of 3.5 μg/mL[2]. Anti-hyperglycemic and anti-inflammatory activities[1].
Homoplantaginin is a flavonoid from a traditional Chinese medicine Salvia plebeia with antiinflammatory and antioxidant properties. Homoplantaginin could inhibit TNF-α and IL-6 mRNA expression, IKKβ and NF-κB phosphorylation.
Kaempferitrin is a natural flavonoid, possesses antinociceptive, anti-inflammatory, anti-diabetic, antitumoral and chemopreventive effects, and activates insulin signaling pathway.
Tangeretin, a flavonoid from citrus fruit peels, has been proven to play an important role in anti-inflammatory responses and neuroprotective effects in several disease models, and was also selected as a Notch-1 inhibitor.IC50 value:Target: Notch-1In vitro: Tangeretin enhanced the radiosensitivity of GC cells as demonstrated by MTT and colony formation assays. Tangeretin also attenuated radiation-induced EMT, invasion and migration in GC cells, accompanied by a decrease in Notch-1, Jagged1/2, Hey-1 and Hes-1 expressions. Tangeretin triggered the upregulation of miR-410, a tumor-suppressive microRNA. Furthermore, re-expression of miR-410 prevented radiation-induced EMT and cell invasion [1]. In vivo: In this study, we investigated the in vivo anti-RSV activity of tangeretin in 3-week-old male BALB/c mice. A plaque reduction assay and fluorescence quantitative polymerase chain reaction (FQ-PCR) showed that tangeretin inhibited RSV replication in the lung of mice [2].
Genistein, a soy isoflavone, is a multiple tyrosine kinases inhibitor which acts as a chemotherapeutic agent against different types of cancer, mainly by altering apoptosis, the cell cycle, and angiogenesis and inhibiting metastasis.
Liquiritigenin, a flavanone isolated from Glycyrrhiza uralensis, is a highly selective estrogen receptor β (ERβ) agonist with an EC50 of 36.5 nM for activation of the ERE tk-Luc.
Kaempferol inhibits estrogen receptor α expression in breast cancer cells and induces apoptosis in glioblastoma cells and lung cancer cells by activation of MEK-MAPK.
(-)-Epigallocatechin is the most abundant flavonoid in green tea, can bind to unfolded native polypeptides and prevent conversion to amyloid fibrils.IC50 value:Target: in vitro: EGCG is a potent inhibitor of amyloidogenic cystatin I66Q amyloid fibril formation in vitro. Computational analysis suggests that EGCG prevents amyloidogenic cystatin fibril formation by stabilizing the molecule in its native-like state as opposed to redirecting aggregation to disordered, amorphous aggregates [1]. Combined curcumin and EGCG treatment reduced the cancer stem-like Cluster of differentiation 44 (CD44)-positive cell population. Western blot and immunoprecipitation analyses revealed that curcumin and EGCG specifically inhibited STAT3 phosphorylation and STAT3-NFkB interaction was retained [2]. EGCG exhibited a MIC and MBC of 5μg/mL and 20μg/mL respectively and effectively eradicated E. faecalis biofilms. EGCG induced the formation of hydroxyl radicals in E. faecalis. The addition of DIP protected E. faecalis against EGCG-mediated antibacterial effects. At sub-MIC, EGCG induced significant down-regulation of E. faecalis virulence genes [3].
Naringin is a major flavanone glycoside obtained from tomatoes, grapefruits, and many other citrus fruits. Naringin exhibits biological properties such as antioxidant, anti-inflammatory, and antiapoptotic activities.
Silibinin, an effective anti-cancer and chemopreventive agent, has been shown to exert multiple effects on cancer cells, including inhibition of both cell proliferation and migration.IC50 value:Target: anticancerin vitro: silibinin significantly induced the expression of the non-steroidal anti-inflammatory drug-activated gene-1 (NAG-1) in both p53 wild-type and p53-null cancer cell lines, suggesting that silibinin-induced NAG-1 up-regulation is p53-independent manner.Silibinin up-regulates early growth response-1 (EGR-1) expression [1]. silibinin induced cell death in human breast cancer cell lines MCF7 and MDA-MB-231. Silibinininduced cell death was attenuated by antioxidants, N-acetylcysteine (NAC) and Trolox, suggesting that the effect of silibinin was dependent on generation of reactive oxygen species (ROS) [2]. SIL treatment resulted in a dose- and time-dependent inhibition of HCC cell viability, SIL exhibited strong antitumor activity, as evidenced not only by reductions in tumor cell adhesion, migration, intracellular glutathione (GSH) levels and total antioxidant capability (T-AOC) but also by increases in the apoptotic index, caspase3 activity, and reactive oxygen species (ROS). SIL treatment decreased the expression of the Notch1 intracellular domain (NICD), RBP-Jκ, and Hes1 proteins, upregulated the apoptosis pathway-related protein Bax, and downregulated Bcl2, survivin, and cyclin D1. Notch1 siRNA (in vitro) or DAPT (a known Notch1 inhibitor, in vivo) further enhanced the antitumor activity of SIL, and recombinant Jagged1 protein (a known Notch ligand in vitro) attenuated the antitumor activity of SIL [3].in vivo: Topical application of silibinin at the dose of 9 mg/mouse effectively suppressed oxidative stress and deregulated activation of inflammatory mediators and tumorigenesis[4]. The kidney cortex of vehicle-treated control OVE26 mice displayed greater Nox4 expression and twice as much superoxide production than cortex of silybin-treated mice. The glomeruli of control OVE26 mice displayed 35% podocyte drop out that was not present in the silybin-treated mice [5].
Ipriflavone is a synthetic isoflavone derivative used to suppress bone resorption.
Luteolin is a falconoid compound, which exhibits anticancer properties.IC50 value:Target: A natural for anticancer.In vitro: Luteolin exerted an anticancer effect against NCI-H460 cells through Sirt1-mediated apoptosis and the inhibition of cell migration [1]. The treatment of luteolin upregulated the expression levels of transforming growth factor β1 (TGF-β1), p21WAF1/CIP1, p27KIP1, Smad4, and Fas in HCC cells. Luteolin induced apoptotic cell death in Hep3B cells while caused G1 arrest in HepG2 cells. And it induces apoptosis from G1 arrest via three signaling pathways of TGF-β1, p53, and Fas/Fas-ligand in HCC cells [2].In vivo: The study of the effect of Luteolin on the improvement of cancerous cachexia in model mice showed that luteolin can improve the symptoms of cancer cachexia model mice.The mechanism may be related to inhibition of proteasome and calcium activated protease activity and lower the levels of cytokines [3].
Daidzin is an isoflavone that has anti-oxidant, anti-carcinogenic, and anti-atherosclerotic activities; directly inhibits mitochondrial aldehyde dehydrogenase 2 (IC50 = 80 nM) and is an effective anti-dipsotropic isoflavone.
Kuromanin (chloride), extracted from mulberry leaves, has been shown to improve blood glucose concentrations and lipid homeostasis and to reduce obesity.
Myricetin is a common plant-derived flavonoid with a wide range of activities including strong anti-oxidant, anticancer, antidiabetic and anti-inflammatory activities.
Theaflavin is a suitable natural inhibitor against influenza A (H1N1) neuraminidase.
7-Hydroxychromone is a Src kinase inhibitor with an IC50 of <300 μM.
Warangalone is an anti-malarial compound which can inhibit the growth of both strains of parasite 3D7 (chloroquine sensitive) and K1 (chloroquine resistant) with IC50s of 4.8 μg/mL and 3.7 μg/mL, respectively. Warangalone can also inhibit cyclic AMP-dependent protein kinase catalytic subunit (cAK) with an IC50 of 3.5 μM.
Podocarpusflavone A is a DNA topoisomerase I inhibitor, have moderated anti-proliferative activity induce cell apoptosis in MCF-7, is developing anti-tumor drugstarget: DNA topoisomerase IIn vitro: podocarpusflavone-A show significant inhibitions against DLD, KB, MCF-7, HEp-2 tumor cell lines (ED50 4.56-16.24 μg/mL) and induce cell apoptosis in MCF-7 via mainly sub-G1/S phase arrest. PF (40 ug/mL, 24 hr) significantly induced about 10 folds of cell deaths and growth arrest in S-phase than the control group.
Galangin is an agonist/antagonist of the arylhydrocarbon receptor, and also shows inhibition of CYP1A1 activity.
(-)-Epicatechin inhibits cyclooxygenase-1 (COX-1) with an IC50 of 3.2 μM. (-)-Epicatechin inhibits the IL-1β-induced expression of iNOS by blocking the nuclear localization of the p65 subunit of NF-κB.
Gastrodenol(Bismuth tripotassium dicitrate; De-Noltab)is a mineral that is used in treating ulcers and upset stomach.
Neohesperidin is a flavonoid compound found in high amounts in Poncirus trifoliata with anti-oxidant and anti-inflammatory effects.
Isobavachalcone(Corylifolinin) is a chalcone constituent of Angelica keiskei, induces apoptosis in neuroblastoma.IC50 value:Target: Isobavachalcone inhibits platelet aggregation. Inhibitor of Epstein-Barr virus early antigen (EBV-EA) induction. Isobavachalcone exhibits potent inhibitory effect on skin tumor promotion. Potent inhibitor of MMP-2. Displays DNA strand-scission (cleaving) activity. Isobavachalcone hows antifungal activity.
Corylin is a major bioactive compound isolated from Psoralea corylifolia L; antibiotic or anticancer compound.IC50 value:Target: in vitro: Corylin showed an inhibitory effect on IL-6-induced STAT3 promoter activity in Hep3B cells with IC50 value of 1.37 uM [1].
Glycitin is a natural isoflavone isolated from legumes; promotes the proliferation of bone marrow stromal cells and osteoblasts and suppresses bone turnover.
Hesperetin is a natural flavanone, and acts as a potent and broad-spectrum inhibitor against human UGT activity.