icaritin and icariin

Inflammation and immunity dysregulation have received widespread attention in recent years due to their occurrence in the pathophysiology of many conditions. In this regard, several pharmacological studies have been conducted aiming to evaluate the potential anti-inflammatory and immunomodulatory effects of phytochemicals. Epimedium, a traditional Chinese medicine, is often used as a tonic, aphrodisiac, and anti-rheumatic agent. Icariin (ICA) is the main active ingredient of Epimedium and is, once ingested, mainly metabolized into Icaritin (ICT). Data from in vitro and in vivo studies suggested that ICA and its metabolite (ICT) regulated the functions and activation of immune cells, modulated the release of inflammatory factors, and restored aberrant signaling pathways. ICA and ICT were also involved in anti-inflammatory and immune responses in several diseases, including multiple sclerosis, asthma, atherosclerosis, lupus nephritis, inflammatory bowel diseases, rheumatoid arthritis, and cancer. Yet, data showed that ICA and ICT exhibited similar but not identical pharmacokinetic properties. Therefore, based on their higher solubility and bioavailability, as well as trends indicating that single-ingredient compounds offer broader and safer therapeutic capabilities, ICA and ICT delivery systems and treatment represent interesting avenues with promising clinical applications. In this study, we reviewed the anti-inflammatory and immunomodulatory mechanisms, as well as the pharmacokinetic properties of ICA and its metabolite ICT.

Topics: Anti-Inflammatory Agents; Epimedium; Flavonoids; Immunity

Icaritin is an aglycone of flavonoid glycosides from Herba Epimedii. It has good performance in the treatment of hepatocellular carcinoma in clinical trials. However, the natural icaritin content of Herba Epimedii is very low. At present, the icaritin is mainly prepared from flavonoid glycosides by α-L-rhamnosidases and β-glucosidases in two-step catalysis process. However, one-pot icaritin production required reported enzymes to be immobilized or bifunctional enzymes to hydrolyze substrate with long reaction time, which caused complicated operations and high costs. To improve the production efficiency and reduce costs, we explored α-L-rhamnosidase SPRHA2 and β-glucosidase PBGL to directly hydrolyze icariin to icaritin in one-pot, and developed the whole-cell catalytic method for efficient icaritin production.. The SPRHA2 and PBGL were expressed in Escherichia coli, respectively. One-pot production of icaritin was achieved by co-catalysis of SPRHA2 and PBGL. Moreover, whole-cell catalysis was developed for icariin hydrolysis. The mixture of SPRHA2 cells and PBGL cells transformed 200 g/L icariin into 103.69 g/L icaritin (yield 95.23%) in 4 h in whole-cell catalysis under the optimized reaction conditions. In order to further increase the production efficiency and simplify operations, we also constructed recombinant E. coli strains that co-expressed SPRHA2 and PBGL. Crude icariin extracts were also efficiently hydrolyzed by the whole-cell catalytic system.. Compared to previous reports on icaritin production, in this study, whole-cell catalysis showed higher production efficiency of icaritin. This study provides promising approach for industrial production of icaritin in the future.

Topics: Escherichia coli; Flavonoids; Glycosides

In this study, a GH78 α-L-rhamnosidase AtRha from Aspergillus terreus CCF3059 was screened and expressed in Pichia pastoris KM71H. The maximum enzyme activity of AtRha was 1000 U/mL after 12 days. AtRha was most active at 65 °C and pH 6.5, displaying excellent thermal stability and pH stability. The kinetic parameters Km, Vmax, kcat and kcat/Km values for pNPR were 0.481 mM, 659 μmol/min·mg, 1065 s-1 and 2214 s-1mM-1, respectively. AtRha could be inhibited by Fe2+, Hg2+ and Cu2+. Moreover, it displayed good tolerance to organic reagents with 52.6% activity in 15%(w/v) methanol. AtRha can hydrolyze icariin containing the α-1 rhamnoside linkage. Furthermore, AtRha and β-glucosidase TthBg3 showed excellent selectivity to cleave the rhamnose at the 3rd position and the glucosyl at the C-7 group of icariin, which established an effective and green method to produce the more pharmacological active icaritin. In addition, the optimal enzyme addition schemes and the reaction conditions were screened and optimized. After a two-stage transformation under optimized conditions, 0.5 g/L of icariin was transformed into 0.25 g/L of icaritin, with a corresponding molar conversion rate of 91.2%. Our findings provide a new, specific and cost-effective method for the production of icaritin in the industry.

Topics: Aspergillus; beta-Glucosidase; Flavonoids; Glycoside Hydrolases

This study aimed to explore the neuroprotective effect of icariin/icaritin (ICA/ICT) and the role of ICA/ICT in the treatment of Alzheimer's disease (AD). ICA and ICT were used to treat okadaic acid (OA)-induced Tau hyperphosphorylation in SH-SY5Y cells. We detected the relative changes in Tau, p-Tau, protein phosphatase 2A (PP2A), and glycogen synthase kinase 3β (GSK-3β) by Western blotting and enzyme-linked immunosorbent assay. At 40 nmol/L OA, the cell viability of the SH-SY5Y cells was significantly changed. We used different concentrations of ICA and IC to treat AD model cells and found that the effect of 2.5 μmol/L ICA and 1 μmol/L ICT was best after 48 H of treatment. After SH-SY5Y cell induction, the p-Tau levels were increased (P < 0.05); after the ICA/ICT treatment, the p-Tau and GSK-3β levels were decreased (P < 0.05), although PP2A expression did not change (P > 0.05). We found that ICA and ICT exert an effect on AD model cells by decreasing the levels of GSK-3β and p-Tau. The therapeutic effect of ICT is slightly better than that of ICA. Although these drugs were effective in the cell model, more studies are required to determine whether they are promising for the treatment and prevention of AD.

Topics: Alzheimer Disease; Flavonoids; Glycogen Synthase Kinase 3 beta; Humans; Phosphorylation; tau Proteins

Topics: Animals; Astrocytes; Cells, Cultured; Disease Models, Animal; Flavonoids; Humans; Lipopolysaccharides; Mesencephalon; Mice; Neuroinflammatory Diseases; Primary Cell Culture; Receptor, IGF Type 1; Signal Transduction

Depression is a chronic, severe, and often life-threatening disease accompanied with impaired neurogenesis. Evidence showed that neuroinflammation played a key role in the process of depression. High mobility group protein box 1 (HMGB1) has been proved to function as a pro-inflammatory cytokine. In this study, we used a social defeat (SD) stress to induce inflammatory response, aiming to explore the relationship between HMGB1 and neuroinflammation. We found that the expression of HMGB1 decreased in mice exposure to SD stress, but showed a high expression of cytoplasmic HMGB1 and a high expression of RAGE, which could be rescued by ICA and ICT. So, we speculated that the translocation of HMGB1 from the nucleus to the cytoplasm might play an important role in neuroinflammatory process, and HMGB1-RAGE signaling was involved in this process. Furthermore, we also found that TLR4-XBP1s-ER stress related NF-κB signaling activation was also involved in HMGB1-related neuroinflammation. However, ICA and ICT treatment activated NF-κB signaling, and we also observed the translocation of HMGB1 into the nucleus and the increased number of neurons in mice hippocampus, indicating that the activation of NF-κB signaling might be related to neuroregeneration. Moreover, recombinant human HMGB1 protein (rHMGB1) pretreatment could suppress HMGB1-RAGE signaling and TLR4-XBP1s-ER stress related NF-κB signaling, resulted in a suppressed microglia activation in mice hippocampus. We supposed that ICA and ICT could ameliorate neuroinflammation in hippocampus via suppressing HMGB1-RAGE signaling and show neuroprotective effects via activating TLR4- NF-κB signaling at the same time, resulting in improving depressive behaviors in mice.

Topics: Animals; Anti-Inflammatory Agents; Behavior, Animal; Cytokines; Disease Models, Animal; Flavonoids; Hippocampus; HMGB1 Protein; Male; Mice, Inbred C57BL; Neuroprotective Agents; NF-kappa B; Receptor for Advanced Glycation End Products; Signal Transduction; Stress, Psychological

Inflammation is a defensive response of the body and is at the center of many diseases' process like depression. High mobility group protein box 1 (HMGB1), has been proved to function as a pro-inflammatory cytokine. We aim to explore the role of HMGB1 played in the neuroinflammation here. In this study, we used LPS to induce an acute inflammatory response, and to measure the anti-neuroinflammation effect of icariin (ICA) and icaritin (ICT). We found that LPS could increase the expression of HMGB1 in serum and hippocampus, along with a high expression of HMGB1 in the cytoplasm and a high expression of RAGE, which could be rescued by ICA and ICT, and ethyl pyruvate (EP) pretreatment showed similar effects here. We speculated that the translocation of HMGB1 from the nucleus to the cytoplasm played an important role in neuroinflammatory process, and HMGB1-RAGE signal was involved in this process. Furthermore, we found that ICA and ICT treatment activated TLR4-XBP1s related NF-κB signal, which we thought was relevant with the neuroprotective effect of ICA and ICT. However, EP pretreatment suppressed TLR4-XBP1s- endoplasmic reticulum stress related NF-κB signal to anti-inflammatory response, which was almost absolutely opposite with ICA and ICT treatment. We speculated that it might be caused by the duration of inflammation. We supposed that ICA and ICT could ameliorate neuroinflammation in hippocampus via suppressing HMGB1-RAGE signaling and might show a neuroprotective effect via activating TLR4-XBP1s related NF-κB signal at the same time, making it possible to act as an anti-neuroinflammatory drugs.

Topics: Animals; Anti-Inflammatory Agents; Disease Models, Animal; Flavonoids; Hippocampus; HMGB1 Protein; Inflammation; Interleukin-10; Lipopolysaccharides; Male; Mice, Inbred C57BL; Neuroprotective Agents; Receptor for Advanced Glycation End Products; Tumor Necrosis Factor-alpha

Topics: Antineoplastic Agents; Apoptosis; ATP Binding Cassette Transporter, Subfamily B; Cell Line, Tumor; Cell Survival; Dose-Response Relationship, Drug; Doxorubicin; Drug Resistance, Multiple; Drug Resistance, Neoplasm; Flavonoids; Gene Expression Regulation, Neoplastic; Humans; Multidrug Resistance-Associated Proteins; Osteosarcoma; Phosphorylation; Rhodamine 123; STAT3 Transcription Factor; Triterpenes

Icariin (ICA) and icaritin (ICT) exhibit many pharmacological functions including anti-osteoporosis, anti-cardiovascular, and anti-cancer activities; however, there are few comprehensive studies that track the detailed effects on UVB-induced photoaging. The recovery effects of ICA and ICT were investigated in UVB-irradiated human keratinocytes (HaCaTs). The results indicated that ICT and ICA showed strong radical scavenging activity, and the reactive oxygen species (ROS) scavenging activity of ICT was superior. UVB-induced matrix metalloproteinase-1 (MMP-1) expression was blocked by ICA via the inhibition of mitogen-activated protein kinase/activator protein 1 (MAPK/AP-1), which directly reduced extracellular matrix (ECM) degradation. ICT activated nuclear factor erythroid 2 related factor 2 (Nrf2) to improve the anti-oxidative stress capacity and suppress nuclear factor-κB (NF-κB) activation, decreasing vascular endothelial growth factor (VEGF) protein, and inflammatory cytokines induced ECM degrading enzyme secretion. Moreover, ICT was more advantageous to improve transforming growth factor beta 1 (TGF-β1) and procollagen type I expression than ICA, promoting the synthesis of collagen. Therefore, ICA and ICT have potential to treat UVB-induced oxidative stress, inflammation and photoaging, and will be posited as a novel strategy to alleviate photodamage.

Topics: Antineoplastic Agents; Antioxidant Response Elements; Cell Line; Cellular Senescence; Flavonoids; Humans; Keratinocytes; NF-E2-Related Factor 2; NF-kappa B; Radiation-Protective Agents; Signal Transduction; Transcription Factor AP-1; Ultraviolet Rays

Prenylated flavonols are known as phytoestrogen and have good bioactivties. However, their abundances in nature are pretty low. It is required to find an efficient synthesis technique. Icariin is a prenylated flavonol glycoside with low cost. It can be used to synthesize different prenylated flavonols. A combination of cellulase and trifluoacetic acid hydrolysis could effectively remove rhamnose and glucose from icariin. Icaritin, anhydroicaritin and wushanicaritin were the leading prenylated flavonol products. Their affinities to estrogen receptors α and β were predicted by docking study. The weak affinity of wushanicaritin indicated that prenyl hydroxylation impaired its affinity to estrogen receptor β. The prenyl cyclization led to a loss of affinity to both receptors. The interactions between icaritin and ligand binding cavity of estrogen receptor β were simulated. π-π stacking and hydrophobic forces were predicted to be the dominant interactions positioning icaritin, which induced the helix (H12) forming an activated conformation.

Topics: Benzopyrans; Binding Sites; Cellulase; Estrogen Receptor alpha; Estrogen Receptor beta; Flavonoids; Glucose; Hydrolysis; Hydrophobic and Hydrophilic Interactions; Hydroxylation; Models, Molecular; Molecular Docking Simulation; Phytoestrogens; Prenylation; Protein Binding; Protein Structure, Secondary; Rhamnose; Trifluoroacetic Acid

Icariin (ICA) and icaritin (ICT), with a similar structure to genistein, are the important bioactive components of the genus Epimedium, and regulate many cellular processes. In the present study, using the estrogen receptor (ER)-negative breast cancer cell line, SKBr3, as a model, we examined the hypothesis that ICA and ICT at low concentrations stimulate SKBr3 cell proliferation in vitro through the functional membrane, G protein‑coupled estrogen receptor 1 (GPER1), mediated by the epithelial growth factor receptor (EGFR)‑mitogen-activated protein kinase (MAPK) signaling pathway. MTT assay revealed that ICA and ICT at doses of 1 nM to 1 µM markedly stimulated SKBr3 cell proliferation in a dose-dependent manner. The ICA- and ICT-stimulated cell growth was completely suppressed by the GPER1 antagonist, G-15, indicating that the ICA‑ and ICT-stimulated cell proliferation was mediated by GPER1 activation. Semi-quantitative RT-PCR analysis revealed that treatment with ICA and ICT enhanced the transcription of c-fos, a proliferation-related early gene. The ICA- and ICT-stimulated mRNA expression was markedly attenuated by G-15, AG-1478 (an EGFR antagonist) or PD98059 (a MAPK inhibitor). Our data also demonstrated that ICA and ICT increased the phosphorylation of ERK1/2. The ICA- and ICT-stimulated ERK1/2 phosphorylation was blocked by pre-treatment of the cells with G-15 and AG-1478 or PD 98059. Flow cytometric analysis confirmed that the ICA- and ICT-stimulated SKBr3 cell proliferation involved the GPER1-mediated modulation of the EGFR‑MAPK signaling pathway. To the best of our knowledge, our current findings demonstrate for the first time that ICA and ICT promote the progression of ER-negative breast cancer through the activation of membrane GPER1.

Topics: Animals; Cell Cycle; Cell Line, Tumor; Cell Proliferation; Flavonoids; Humans; MAP Kinase Signaling System; Receptors, Estrogen; Receptors, G-Protein-Coupled

Flavonoids isolated from Herba Epimedii such as icaritin, icariin and epimedin C have been suggested as potential bone anabolic compounds. However, the "specific localized effects" of these flavonoids in bone, in vivo, and the metabolism of these flavonoids in zebrafish larvae have never been demonstrated. In this study, we used multiple methods including in vivo imaging, drug metabolites profiling, transcriptomic and proteomic approaches to determine the mechanisms involved in the distribution and metabolism of the flavonoids in zebrafish larvae by measuring the fluorescence emission, in vivo, of icaritin and its glycoside derivatives. The fluorescence emission mechanism of icaritin in vitro was identified by spectrophotometric analysis, and the fluorescent property of icaritin was used as a probe to visualize the metabolism and distribution of icaritin and its glycoside derivatives in zebrafish larvae. Phase I and phase II metabolism of icaritin and its derivatives were identified in zebrafish by mass spectrometry. The combined transcriptomics and proteomics demonstrate a high degree of conservation of phase I and phase II drug metabolic enzymes between zebrafish larvae and mammals. Icaritin and its glycoside derivatives were demonstrated using combined approaches of in vivo imaging, drug metabolites identification, and transcriptomic and proteomic profiling to illustrate phase I and phase II metabolism of the flavonoids and their distribution in bone of zebrafish larvae. This study provides a new methodological model for use of the zebrafish larvae to examine drug metabolism.

Topics: Amino Acid Sequence; Animals; Bone and Bones; Calcification, Physiologic; Calcium; Cattle; Chromatography, Liquid; Flavonoids; Fluorescence; Gene Expression Profiling; Glycosides; Imaging, Three-Dimensional; Inactivation, Metabolic; Larva; Mass Spectrometry; Molecular Sequence Data; Organ Specificity; Peptides; Proteomics; Serum Albumin, Bovine; Spectrophotometry; Time Factors; Zebrafish

A series of icariin derivatives were synthesized. Their multidrug resistance (MDR) reversal activities were evaluated by MTT assay and the results indicated that the derivatives were the potent modulators of MDR. It was showed that the derivatives significantly increased the intracellular accumulation of ADR in MCF-7/ADR cells compared with drug sensitive MCF-7 cells. The results of bi-directional assay and reverse transcription polymerase chain reaction (RT-PCR) assay showed that the derivatives had high inhibitory activity against P-gp efflux function and significantly down-regulated on the expression of P-gp.

Topics: Antineoplastic Agents; ATP Binding Cassette Transporter, Subfamily B, Member 1; Caco-2 Cells; Cell Line, Tumor; Chemistry, Pharmaceutical; Drug Design; Drug Resistance, Multiple; Drug Resistance, Neoplasm; Flavonoids; Humans; Inhibitory Concentration 50; Models, Chemical; Reverse Transcriptase Polymerase Chain Reaction; Tetrazolium Salts; Thiazoles; Time Factors

Plant extracts traditionally used for male impotence (Tribulus terrestris, Ferula hermonis, Epimedium brevicornum, Cinnamomum cassia), and the individual compounds cinnamaldehyde, ferutinin, and icariin, were screened against phosphodiesterase-5A1 (PDE5A1) activity. Human recombinant PDE5A1 was used as the enzyme source. Only E. brevicornum extract (80% inhibition at 50 microg/mL) and its active principle icariin (1) (IC50 5.9 microM) were active. To improve its inhibitory activity, 1 was subjected to various structural modifications. Thus, 3,7-bis(2-hydroxyethyl)icaritin (5), where both sugars in 1 were replaced with hydroxyethyl residues, potently inhibited PDE5A1 with an IC50 very close to that of sildenafil (IC50 75 vs 74 nM). Thus, 5 was 80 times more potent than 1, and its selectivity versus phosphodiesterase-6 (PDE6) and cyclic adenosine monophosphate-phosphodiesterase (cAMP-PDE) was much higher in comparison with sildenafil. The improved pharmacodynamic profile and lack of cytotoxicity on human fibroblasts make compound 5 a promising candidate for further development.

Topics: Cyclic Nucleotide Phosphodiesterases, Type 6; Epimedium; Erectile Dysfunction; Ferula; Flavonoids; Humans; Inhibitory Concentration 50; Male; Molecular Structure; Phosphodiesterase 5 Inhibitors; Phosphodiesterase Inhibitors; Piperazines; Plant Extracts; Purines; Sildenafil Citrate; Structure-Activity Relationship; Sulfones; Tribulus

The significant promoting effects of some prenylflavonoids on cardiac differentiation of mouse embryonic stem (ES) cells via reactive oxygen species (ROS) signaling pathway were investigated. The most effective differentiation was facilitated by icariin (ICA), followed by icaritin (ICT), while desmethylicaritin (DICT) displayed the weakest but still significant inducible effect. Contrarily, DICT demonstrated the strongest anti-oxidative activity while ICA displayed only little in vitro, which was well matched with the hydroxyl (OH) numbers and the positions in the molecular structures. Therefore, ROS signaling cascades were assumed to be involved in prenylflavonoids induced cardiomyogenesis. Treatment with ICA, intracellular ROS in embryoid bodies was rapidly elevated, which was abolished by the NADPH-oxidase inhibitor apocynin; elimination of intracellular ROS by vitamin E or pyrrolidine dithiocarbamate (PDTC) inhibited ICA induced cardiomyogenesis; ROS-sensitive extracellular-regulated kinase 1, 2 (ERK1, 2) and p38 activation were further observed, the cardiomyogenesis was significantly inhibited in the presence of ERK1, 2 or p38 inhibitor U0126 or SB203580, indicating the roles of NADPH-ROS-MAPKs signaling cascades in prenylflavonoids induced cardiac differentiation. There was no difference in Nox4 NADPH oxidase expression between ICA and ICT treatments, however, ROS concentration in EBs after ICT administration was lower than that after ICA treatment, followed by less activation of ERK1, 2, and p38. These results revealed that the significant promoting effects of prenylflavonoids on cardiac differentiation was at least partly via ROS signaling cascades, and the facilitating abilities preferentially based on the nature of prenylflavonoids themselves, but anti-oxidative activity determined by the OH numbers and the positions in the structures do influence the cardiomyogenesis in vitro.

Topics: Animals; Cell Differentiation; Cell Line; Embryonic Stem Cells; Enzyme Inhibitors; Flavonoids; MAP Kinase Signaling System; Mice; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Myocytes, Cardiac; NADPH Oxidase 4; NADPH Oxidases; p38 Mitogen-Activated Protein Kinases; Reactive Oxygen Species

Three kinds of prenylated flavonols, icariside I, icariside II, and icaritin, were isolated from an icariin hydrolysate and their effects on melanogenesis evaluated based on mushroom tyrosinase inhibition and quantifying the melanin contents in melanocytes. Although none of the compounds had an effect on tyrosinase activity, icariside II and icaritin both effectively inhibited the melanin contents with an IC50 of 10.53 and 11.13 MM, respectively. Whereas icariside II was obtained from a reaction with beta-glucosidase and cellulase, the icariin was not completely converted into icariside II. Thus, for the high-purity production of icariside II, the reaction was optimized using the response surface methodology, where an enzyme concentration of 5.0 mg/ml, pH 7, 37.5 degrees C;, and 8 h reaction time were selected as the central conditions for the central composite design (CCD) for the enzymatic hydrolysis of icariin into icariside II using cellulase. Empirical models were developed to describe the relationships between the operating factors and the response (icariside II yield). A statistical analysis indicated that all four factors had a significant effect (p<0.01) on the icariside II production. The coefficient of determination (R2) was good for the model (0.9853), and the optimum production conditions for icariside II was an enzyme concentration of 7.5 mg/ml, pH 5, 50 degrees C, and 12 h reaction time. A good agreement between the predicted and experimental data under the designed optimal conditions confirmed the usefulness of the model. A laboratory pilot scale was also successful.

Topics: Animals; Biotechnology; Cell Line, Tumor; Chromatography, High Pressure Liquid; Epimedium; Flavones; Flavonoids; Hydrogen-Ion Concentration; Hydrolysis; Mass Spectrometry; Melanins; Melanocytes; Mice; Mice, Inbred C57BL; Monophenol Monooxygenase; Umbelliferones

Icariin and icaritin with prenyl group have been demonstrated for their selective estrogen receptor modulating activities. We screened their effects on cell growth in human prostate carcinoma PC-3 cell line (estrogen receptor positive) in vitro. PC-3 cell line was used for the measurement of anti-carcinoma activities of 0-100 micromol/l icaritin and 30 micromol/l icariin. 1 micromol/l 17-beta estradiol (E(2)) served as the estrogen positive control, and 1 micromol/l ICI 182,780 [7 alpha-[9 (4,4,5,5,5-pentafluoropentyl) sulfinyl] nonyl]-estra-1,3,5(10)-triene-3,17h-diol]] served as the specific estrogen receptor antagonist. Primary cultured rat prostate basal cells used as cell growth selective control. The growth-inhibitory effects were analyzed using MTT assay, and fluorochrome staining, flow cytometry, and immunoblotting were employed to illustrate the possible mechanisms. When treated with icaritin for 24 to 72 h, cell growth was strongly inhibited (at 48 h IC(50) was 10.74+/-1.59 micromol/l, P<0.001) companied with a mitochondrial transmembrane potential (_Psim) drop. Meanwhile, few changes in IC(50) could be observed when co-incubated with ICI 182,780. Icaritin-induced growth inhibition was associated with G(1) arrest (P<0.05), and G(2)-M arrest depending upon doses. Consistently with G(1) arrest, icaritin increased protein expressions of pRb, p27(Kip1) and p16(Ink4a), while showed decrease in phosphorylated pRb, Cyclin D1 and CDK4. Comparatively, icariin has much lower effects on PC-3 cells and showed only weak G(1) arrest, suggesting a possible structure-activity relationship. These findings suggested a novel anticancer efficacy of icaritin mediated selectively via induction of cell cycle arrest but not associated with estrogen receptors in PC-3 cells.

Topics: Antineoplastic Agents, Phytogenic; Blotting, Western; Carcinoma; Cell Cycle; Cell Cycle Proteins; Cell Line, Tumor; Cell Proliferation; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; Estradiol; Flavonoids; Flow Cytometry; G1 Phase; G2 Phase; Humans; Immunoblotting; Inhibitory Concentration 50; Male; Membrane Potential, Mitochondrial; Prostatic Neoplasms

To investigate the possible inducible effects of icariin, icaritin, and desmethylicaritin on the directional differentiation of embryonic stem (ES) cells into cardiomyocytes in vitro.. ES cells were cultivated as embryoid bodies (EBs) in hanging drops with icariin, icaritin, or desmethylicaritin. ES cells treated with retinoic acid and with solvent were used as positive and negative controls, respectively. The cardiomyocytes derived from the ES cells were verified using immunocytochemistry. The expression of cardiac developmental-dependent genes was detected using the reverse transcription-polymerase chain reaction (RT-PCR) method. Cell cycle distribution and apoptosis were analyzed using flow cytometry to determine the partly inducible effect mechanisms involved.. The total percentage of beating EBs treated with 10(-7) mol/L icariin, icaritin, or desmethylicaritin was 87% (P<0.01), 59% (P<0.01), and 49%, respectively. All the beating cardiomyocytes derived from the ES cells expressed cardiac-specific proteins for a-actinin and troponin T. Among them, 10(-7) mol/L icariin treatment resulted in a significantly advanced and increased mRNA level of a-cardiac major histocompatibility complex (MHC) and myosin light chain 2v (MLC-2v) in EBs in the early cardiac developmental stage. Before shifting to the cardiomyocyte phenotype, icariin could evoke the accumulation of ES cells in G0/G1 and accelerate apoptosis of the cell population (P<0.05).. Icariin facilitated the directional differentiation of ES cells into cardiomyocytes at a concentration of 10(-7) mol/L. The promoting effect of icariin on cardiac differentiation was related to increasing and accelerating gene expression of a-cardiac MHC and MLC-2v, as well as regulating the cell cycles and inducing apoptosis.

Topics: Animals; Apoptosis; Cell Cycle; Cell Differentiation; Cells, Cultured; Embryo, Mammalian; Epimedium; Female; Flavonoids; Gene Expression Regulation; Male; Mice; Myocytes, Cardiac; Myosin Heavy Chains; Myosin Light Chains; Plants, Medicinal; RNA, Messenger; Stem Cells

To investigate the estrogen-like activities of icariin (ICA), icaritin (ICT) and desmethylicaritin (DICT) and their structure/activity relationships.. ICT was hydrolyzed from ICA by cellulase and then DICT was demethylated from ICT in boron tribromide and dichloromethane system. Estrogen-sensitive MCF-7 cells and T47D cells were co-incubated with different concentrations of test compounds for 6 and 9 d respectively, and the cell proliferation was measured by MTT.. ICT and DICT both markedly enhanced cell proliferation. Compared with estradiol (10.(-9) mol/L), the proliferative effects of 10.-6 mol/L ICT and DICT on MCF-7 cells were 90.0% and 94.0% (P<0.01), respectively, and those of T47D cells were 65.6% and 50.0%. (P<0.01). But this phenomenon was not observed with ICA. Cell proliferation induced by ICT and DICT was completely antagonized by 10.(-7 )mol/L pure estrogen receptor antagonist, ICI182,780.. ICT and DICT possess estrogen-like activity of enhancing proliferation in MCF-7 and T47D cells. However, ICA appears to have no estrogenicity on MCF-7 and T47D cell lines in vitro.

Topics: Breast Neoplasms; Cell Division; Drugs, Chinese Herbal; Flavonoids; Humans; Phytoestrogens; Tumor Cells, Cultured

The aims of the present study were to determine the estrogenic activities of icariin (ICA) and its derivatives and their structure-estrogenic activity relationship. Therefore, icaritin (ICT) and desmethylicaritin (DICT) were derived from ICA. The estrogenic activities of ICA, ICT and DICT were examined by cell proliferation and progestogen receptor mRNA expression of estrogen-receptor-positive MCF-7 cells. Current studies exhibited that ICT and DICT both markedly enhanced the proliferation of MCF-7 cells; as compared to estradiol (100%), their relative proliferative effects (RPE) were 90% and 94%, respectively. Cell proliferation induced by ICT and DICT was completely antagonized by ICI182,780. ICT and DICT increased progestogen receptor (PR) at mRNA levels at 48 h after treatment, although the effects were not as prominent as 17beta-estradiol (E2). Those phenomena were not observed with ICA. Results demonstrate that ICT and DICT (nonconjugated forms) possess estrogen-like activity; however, ICA appears to have no estrogenicity in the MCF-7 cell line model in vitro.

Topics: Breast Neoplasms; Cell Line, Tumor; Cell Proliferation; Drugs, Chinese Herbal; Estrogen Receptor Modulators; Female; Flavonoids; Humans; Receptors, Progesterone; Structure-Activity Relationship; Transcription, Genetic