CYP2C9 （Ki = 2 μM）; Natural flavonoid; antioxidative; anti-inflammatory; anti-viral; anti-tumor

Ki is 2 μM reductase, cytochrome b5, and liposomes in the CYP2C9 RECO system (a purified recombinase system incorporating recombinant human CYP2C9, P450)[1]. Apigenin (4',5,7-Trihydroxyflavone) inhibits cytochrome P450 2C9 (CYP2C9). Cell proliferation is inhibited by apigenin. Apigenin's seventh growth inhibition rates (IR) at 20, 40, and 80 μM were 38%, 71%, and 99%, in that order. After being exposed to Apigenin for 24 or 48 hours, the clonogenesis of SGC-7901 cells was suppressed in a manner that was dependent on both time and dose. Following 24 and 48 hours of Apigenin treatment, the cloning efficiency of 80 μM was 9.8% and 5%, respectively, compared to 40.4% and 43.4% for the control group [2].

Natural flavone apigenin (4',5,7-trihydroxyflavone) has a variety of biological activities, such as anti-inflammatory, neuroprotective, anti-cancer, and antioxidant capabilities. The myocardial damage caused by Adriamycin (ADR) (24 mg/kg) is lessened by apigenin (125 mg/kg and 250 mg/kg). Apigenin prevents serum aspartate aminotransferase (AST) from being released. Serum lactate dehydrogenase (LDH) release is decreased by apelin. Serum creatine kinase (CK) levels are lowered by apigenin [3].

Measurement of Myocardial Enzymes[3]
Serum aspartate amino transferase (AST), lactate dehydrogenase (LDH), and creatine kinase (CK) were measured to assess myocardial injury. These myocardial enzymes were measured using kits. The detailed procedures were performed according to the manufacturer's instructions for the different reagent kits.

The effects of apigenin on the growth, clone formation and proliferation of human gastric carcinoma SGC-7901 cells were observed by MTT, clone-forming assay, and morphological observation. Fluorescent staining and flow cytometry analysis were used to detect apoptosis of cells. Results: Apigenin obviously inhibited the growth, clone formation and proliferation of SGC-7901 cells in a dose-dependent manner. Inhibition of growth was observed on d 1 at the concentration of 80 micromol/L, while after 4 d, the inhibition rate (IR) was 90%. The growth IRs at the concentration of 20, 40, and 80 micromol/L were 38%, 71%, and 99% respectively on the 7th d. After the cells were treated with apigenin for 48 h, the number of clone-forming in control, 20, 40, and 80 micromol/L groups was 217+/-16.9, 170+/-11.1 (P < 0.05), 98+/-11.1 (P < 0.05), and 25+/-3.5 (P < 0.05) respectively. Typical morphological changes of apoptosis was found by fluorescent staining. The cell nuclei had lost its smooth boundaries, chromatin was condensed, and cell nuclei were broken. Flow cytometry detected typical apoptosis peak. After the cells were treated with apigenin for 48 h, the apoptosis rates were 5.76%, 19.17%, and 29.30% respectively in 20, 40, and 80 micromol/L groups. Conclusion: Apigenin shows obvious inhibition on the growth and clone formation of SGC-7901 cells by inducing apoptosis[2].

apigenin was mixed with 0.5% sodium carboxymethyl cellulose (CMC-Na) to form a suspension. All API-treated groups were treated daily via gastric gavage for seventeen days with a 125 or 250 mg/kg/day dose as described above. The ADR-only and control (NC) groups were treated with vehicle (CMC-Na) only. At the end of experiment, three mice died in ADR group and three and one mice died in low-dose and high-dose apigenin treatment group, respectively. These mice all died due to cardiomyotoxicity. On the 17th day after the first treatment, the mice were sacrificed, and blood samples were collected. A number of hearts were fixed with 2.5% glutaraldehyde fixative for electron microscopy analysis, and the others were stored at −80°C for western blot analysis.[3]

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12.5 mg/kg

Mice

Absorption, Distribution and Excretion
Four hours after administration of a flavonoid glycoside extract (corresponding to 0.942 mg aglycones) by gavage, the aglycone of apigenin was observed in the lumen and the wall of the stomach, in the lumen of the small intestine and in the lumen and wall of the cecum in Wistar rats. The evidence of glycosides in the stomach wall suggested that the absorption of flavonoids did not require the presence of their aglycones. Under the study conditions, no renal excretion of apigenin was detected ...
Apigenin appears to be absorbable by humans after intake of parsley (Petroselinum crispum). In a randomized crossover study with two one-week intervention periods in succession, fourteen volunteers consumed a diet that included 20 g parsley. The urinary excretion of apigenin was significantly higher (P < 0.05) during the intervention with parsley (20.7 to 5727.3 g/24 hr) than during the basic diet (0 to 1571.7 g/24 hr). The half-life for apigenin was calculated to be on the order of 12 hr. Significant individual variation in the bioavailability and excretion of apigenin was observed ...
... Eleven healthy subjects (5 women, 6 men) in the age range of 23 to 41 years and with an average body mass index of 23.9 + or - 4.1 kg/sq m took part in this study. After an apigenin- and luteolin-free diet, a single oral bolus of 2 g blanched parsley (corresponding to 65.8 + or - 15.5 umol apigenin) per kilogram body weight was consumed. Blood samples were taken at 0, 4, 6, 7, 8, 9, 10, 11 and 28 hr after parsley consumption and 24-hour urine samples were collected ... On average, a maximum apigenin plasma concentration of 127 + or - 81 nmol/L was reached after 7.2 + or - 1.3 hr with a high range of variation between subjects. For all participants, plasma apigenin concentration rose after bolus ingestion and fell within 28 hr under the detection limit (2.3 nmol/L). The average apigenin content in 24-hour urine was 144 + or - 110 nmol/24 hr corresponding to 0.22 + or - 0.16% of the ingested dose. The flavone could be detected in red blood cells without showing dose-response characteristics.
... The present paper shows the study of the absorption and excretion of luteolin and apigenin in rats after a single oral dose of Chrysanthemum morifolium extract (CME) (200 mg/kg). The levels of luteolin and apigenin in plasma, urine, feces, and bile were measured by HPLC after deconjugation with hydrochloric acid or beta-glucuronidase/sulfatase. The results showed that the plasma concentrations of luteolin and apigenin reached the highest peak level at 1.1 and 3.9 hr after dosing, respectively. The area under the concentration-time curves (AUC) for luteolin and apigenin were 23.03 and 237.6 ug h/mL, respectively. The total recovery of the dose was 37.9% (6.6% in urine; 31.3% in feces) for luteolin and 45.2% (16.6% in urine; 28.6% in feces) for apigenin. The cumulative luteolin and apigenin excreted in the bile was 2.05% and 6.34% of the dose, respectively. All of the results suggest apigenin may be absorbed more efficiently than luteolin in CME in rats, and both luteolin and apigenin have a slow elimination phase, with a quick absorption, so a possible accumulation of the two flavonoids in the body can be hypothesized.
After a single oral administration of radiolabeled apigenin /to rats/, 51.0% of radioactivity was recovered in urine, 12.0% in feces, 1.2% in the blood, 0.4% in the kidneys, 9.4% in the intestine, 1.2% in the liver, and 24.8% in the rest of the body within 10 days. Sex differences appear with regard to the nature of compounds eliminated via the urinary route: immature male and female rats, like mature female rats, excreted a higher percentage of the mono-glucuronoconjugate of apigenin than the mono-sulfoconjugate of apigenin (10.0 to 31.6% versus 2.0 to 3.6%, respectively). Mature male rats excreted the same compounds in an inverse ratio (4.9% and 13.9%, respectively). Radioactivity appeared in the blood only 24 hr after oral administration. Blood kinetics showed a high elimination half-time (91.8 hr), a distribution volume of 259 mL, and a plasmatic clearance of 1.95 mL/hr. All of the parameters calculated from these experiments suggested a slow metabolism of apigenin, with a slow absorption and a slow elimination phase. Thus, a possible accumulation of this flavonoid in the body can be hypothesized.

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Metabolism / Metabolites
Ether extracts of the urine of male Wistar rats administered apigenin (200 mg) orally contained the phenolic acid metabolites phydroxyphenylpropionic acid, p-hydroxycinnamic acid, and p-hydroxybenzoic acid. Unreacted apigenin, partially characterized apigenin glucuronides, and ethereal sulfates were also identified. With the exception of p-hydroxybenzoic acid and the apigenin conjugates, all of the metabolites detected in the urine after oral administration were also formed in vitro by rat intestinal microorganisms under anaerobic conditions ... In contrast, these metabolites were not detected in SENCAR mice treated topically with apigenin. Furthermore, no evidence of metabolites were observed from the HPLC profiles of epidermal extracts from apigenin-treated mice ...
The main in vitro metabolite of apigenin in rat liver Aroclor 1254-induced microsomes has been identified tentatively as the corresponding 3'-hydroxylated compound, luteolin. Apigenin itself is the 3'-hydroxylated metabolite of chrysin ...
Apigenin has known human metabolites that include (2S,3S,4S,5R)-3,4,5-Trihydroxy-6-[5-hydroxy-2-(4-hydroxyphenyl)-4-oxochromen-7-yl]oxyoxane-2-carboxylic acid.

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Biological Half-Life
... The half-life for apigenin was calculated to be on the order of 12 hr ...

Effects During Pregnancy and Lactation
◉ Summary of Use during Lactation
Two different plant species with similar effects are known as chamomile: German chamomile (Matricaria recutita) and Roman chamomile (Chamaemelum nobile). Both contain similar ingredients, including sesquiterpenes (e.g., bisabolol, farnesene), sesquiterpenelactones (e.g., chamazulene, matricin), flavonoids (e.g., apigenin, luteolin), and volatile oils. Chamomile is used orally as a sedative and for gastrointestinal conditions; it is used topically for wound healing. Both herbal and homeopathic preparations have been used to treat mastitis and cracked, bleeding nipples. Chamomile has been used as a galactogogue; however, no scientifically valid clinical trials support this use. Galactogogues should never replace evaluation and counseling on modifiable factors that affect milk production.
Chamomile is "generally recognized as safe" (GRAS) for use in food by the U.S. Food and Drug Administration as a spice, seasoning, or flavoring agent. No data exist on the safety of chamomile in nursing mothers or infants, although rare sensitization may occur (see below). It has been safely and effectively used alone and with other herbs in infants for the treatment of colic, diarrhea, and other conditions, so the smaller amounts expected (but not demonstrated) in breastmilk are likely not to be harmful with usual maternal doses. Note that Clostridium botulinum (botulism) spores have been found in some loose-leaf chamomile teas sold in health food stores.
Topical chamomile is a known sensitizing agent, even with homeopathic products. Two women developed contact dermatitis of the nipples and areolas after applying Kamillosan ointment for cracked nipples. The product was purchased in England and contained 10.5% Roman chamomile extracts and oil. Reactions were confirmed to be caused by Roman chamomile by patch testing in both women. Drinking chamomile tea can exacerbate topical skin rashes and has caused anaphylaxis in sensitized individuals. Chamomile has possible cross-reactivity with other members of the aster family (e.g., echinacea, feverfew, and milk thistle).
Dietary supplements do not require extensive pre-marketing approval from the U.S. Food and Drug Administration. Manufacturers are responsible to ensure the safety, but do not need to prove the safety and effectiveness of dietary supplements before they are marketed. Dietary supplements may contain multiple ingredients, and differences are often found between labeled and actual ingredients or their amounts. A manufacturer may contract with an independent organization to verify the quality of a product or its ingredients, but that does not certify the safety or effectiveness of a product. Because of the above issues, clinical testing results on one product may not be applicable to other products. More detailed information about dietary supplements is available elsewhere on the LactMed Web site.
◉ Effects in Breastfed Infants
Relevant published information was not found as of the revision date.
◉ Effects on Lactation and Breastmilk
A mother nursing her 3-month-old infant began drinking 1.5 to 2 L daily of a chamomile infusion made by pouring 1.5 L of hot water over 1 to 3 grams of chamomile flowers. Each time after drinking the infusion, she noticed fullness and tenderness of the breasts 4 to 6 hours later. She also found that she was able to pump 90 mL of milk after chamomile use, compared to 60 mL without chamomile use. During this time she was also mildly hypothyroid.

[1]. Mechanism of CYP2C9 inhibition by flavones and flavonols. Drug Metab Dispos. 2009 Mar;37(3):629-34.

[2]. Inhibitory effects of apigenin on the growth of gastric carcinoma SGC-7901 cells. World J Gastroenterol. 2005 Aug 7;11(29):4461-4.

[3]. Apigenin Attenuates Adriamycin-Induced Cardiomyocyte Apoptosis via the PI3K/AKT/mTOR Pathway. Evid Based Complement Alternat Med. 2017;2017:2590676.

Apigenin is a trihydroxyflavone that is flavone substituted by hydroxy groups at positions 4', 5 and 7. It induces autophagy in leukaemia cells. It has a role as a metabolite and an antineoplastic agent. It is a conjugate acid of an apigenin-7-olate.
Apigenin has been reported in Camellia sinensis, Apis, and other organisms with data available.
Apigenin is a plant-derived flavonoid that has significant promise as a skin cancer chemopreventive agent. Apigenin inhibits the expression of involucrin (hINV), a marker of keratinocyte differentiation, is increased by differentiating agents via a protein kinase Cdelta (PKCdelta), Ras, MEKK1, MEK3 cascade that increases AP1 factor level and AP1 factor binding to DNA elements in the hINV promoter. Apigenin suppresses the 12-O-tetradeconylphorbol-13-acetate-dependent increase in AP1 factor expression and binding to the hINV promoter and the increase in hINV promoter activity. Apigenin also inhibits the increase in promoter activity observed following overexpression of PKCdelta, constitutively active Ras, or MEKK1. The suppression of PKCdelta activity is associated with reduced phosphorylation of PKCdelta-Y311. Activation of hINV promoter activity by the green tea polyphenol, (-)-epigellocathecin-3-gallate, is also inhibited by apigenin, suggesting that the two chemopreventive agents can produce opposing actions in keratinocytes. (A7924). Apigenin, a flavone abundantly found in fruits and vegetables, exhibits antiproliferative, anti-inflammatory, and antimetastatic activities through poorly defined mechanisms. This flavonoid provides selective activity to promote caspase-dependent-apoptosis of leukemia cells and uncover an essential role of PKCdelta during the induction of apoptosis by apigenin. (A7925). Apigenin markedly induces the expression of death receptor 5 (DR5) and synergistically acts with exogenous soluble recombinant human tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) to induce apoptosis in malignant tumor cells. On the other hand, apigenin-mediated induction of DR5 expression is not observed in normal human peripheral blood mononuclear cells. Moreover, apigenin does not sensitize normal human peripheral blood mononuclear cells to TRAIL-induced apoptosis. (A7926).
5,7,4'-trihydroxy-flavone, one of the FLAVONES.
See also: Flavone (subclass of); Chamomile (part of); Fenugreek seed (part of) ... View More ...

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Mechanism of Action
The dietary flavonoid apigenin (Api) has been demonstrated to exert multiple beneficial effects upon the vascular endothelium. The aim of this study was to examine whether Ca(2+)-activated K(+) channels (K(Ca)) are involved in endothelial nitric oxide (NO) production and antiangiogenic effects ... Endothelial NO generation was monitored using a cyclic guanosine monophosphate radioimmunoassay. K(Ca) activity and changes of the intracellular Ca(2+) concentration [Ca(2+)](i) were analyzed using the fluorescent dyes bis-barbituric acid oxonol, potassium-binding benzofuran isophthalate, and fluo-3. The endothelial angiogenic parameters measured were cell proliferation, [(3)H]-thymidine incorporation, and cell migration (scratch assay). Akt phosphorylation was examined using immunohistochemistry ... Api caused a concentration-dependent increase in cyclic guanosine monophosphate levels, with a maximum effect at a concentration of 1 uM. Api-induced hyperpolarization was blocked by the small and large conductance K(Ca) inhibitors apamin and iberiotoxin, respectively. Furthermore, apamin and iberiotoxin blocked the late, long-lasting plateau phase of the Api-induced biphasic increase of [Ca(2+)](i). Inhibition of Ca(2+) signaling and the K(Ca) blockade both blocked NO production. Prevention of all three (NO, Ca(2+), and K(Ca) signaling) reversed the antiangiogenic effects of Api under both basal and basic fibroblast growth factor-induced culture conditions. Basic fibroblast growth factor-induced Akt phosphorylation was also reduced by Api ... Based on ... /the/ experimental results ... /the authors/ propose the following signaling cascade for the effects of Api on endothelial cell signaling. Api activates small and large conductance K(Ca), leading to a hyperpolarization that is followed by a Ca(2+) influx. The increase of [Ca(2+)](i) is responsible for an increased NO production that mediates the antiangiogenic effects of Api via Akt dephosphorylation.
... Apigenin inhibits the production of proinflammatory cytokines IL-1beta, IL-8, and TNF in LPS-stimulated human monocytes and mouse macrophages. The inhibitory effect on proinflammatory cytokine production persists even when apigenin is administered after LPS stimulation. Transient transfection experiments using NF-kappaB reporter constructs indicated that apigenin inhibits the transcriptional activity of NF-kappaB in LPS-stimulated mouse macrophages. The classical proteasome-dependent degradation of the NF-kappaB inhibitor IkappaBalpha was observed in apigenin LPS-stimulated human monocytes. Using EMSA ... apigenin does not alter NF-kappaB-DNA binding activity in human monocytes. Instead ... apigenin, as part of a non-canonical pathway, regulates NF-kappaB activity through hypophosphorylation of Ser536 in the p65 subunit and the inactivation of the IKK complex stimulated by LPS. The decreased phosphorylation on Ser536 observed in LPS-stimulated mouse macrophages treated with apigenin was overcome by the over-expression of IKKbeta. In addition ... /the/ studies indicate that apigenin inhibits in vivo LPS-induced TNF and the mortality induced by lethal doses of LPS. Collectively, these findings suggest a molecular mechanism by which apigenin suppresses inflammation and modulates the immune response in vivo.
Treatment of /human prostate cancer/ LNCaP and PC-3 cells with apigenin causes G0-G1 phase arrest, decrease in total Rb protein and its phosphorylation at Ser780 and Ser807/811 in dose- and time-dependent fashion. Apigenin treatment caused increased phosphorylation of ERK1/2 and JNK1/2 and this sustained activation resulted in decreased ELK-1 phosphorylation and c-FOS expression thereby inhibiting cell survival. Use of kinase inhibitors induced ERK1/2 phosphorylation, albeit at different levels, and did not contribute to cell cycle arrest in comparison to apigenin treatment. Despite activation of MAPK pathway, apigenin caused a significant decrease in cyclin D1 expression that occurred simultaneously with the loss of Rb phosphorylation and inhibition of cell cycle progression. The reduced expression of cyclin D1 protein correlated with decrease in expression and phosphorylation of p38 and PI3K-Akt, which are regulators of cyclin D1 protein. Interestingly, apigenin caused a marked reduction in cyclin D1, D2 and E and their regulatory partners CDK 2, 4 and 6, operative in G0-G1 phase of the cell cycle. This was accompanied by a loss of RNA polymerase II phosphorylation, suggesting the effectiveness of apigenin in inhibiting transcription of these proteins. This study provides an insight into the molecular mechanism of apigenin in modulating various tyrosine kinases and perturbs cell cycle progression, suggesting its future development and use as anticancer agent in humans.
The aim of this study was to clarify the anti-inflammatory mechanism of apigenin. Apigenin inhibited the collagenase activity involved in rheumatoid arthritis (RA) and suppressed lipopolysaccharide (LPS)-induced nitric oxide (NO) production in a dose dependent manner in RAW 264.7 macrophage cells. Pretreatment with apigenin also attenuated LPS-induced cyclooxygenase-2 (COX-2) expression. In addition, apigenin profoundly reduced the tumor necrosis factor-alpha (TNF-alpha)-induced adhesion of monocytes to HUVEC monolayer. Apigenin significantly suppressed the TNF-alpha-stimulated upregulation of vascular cellular adhesion molecule-1 (VCAM-1)-, intracellular adhesion molecule-1 (ICAM-1)-, and E-selectin-mRNA to the basal levels. Taken together, these results suggest that apigenin has significant anti-inflammatory activity that involves blocking NO-mediated COX-2 expression and monocyte adherence ...
For more Mechanism of Action (Complete) data for APIGENIN (16 total), please visit the HSDB record page.

C15H10O5

270.24

270.052

C, 66.67; H, 3.73; O, 29.60

520-36-5

Apigenin 7-glucoside;578-74-5

5280443

Light yellow to green yellow solid powder

1.5±0.1 g/cm3

555.5±50.0 °C at 760 mmHg

>300 °C(lit.)

217.1±23.6 °C

0.0±1.6 mmHg at 25°C

1.732

2.1

3

5

1

20

411

0

KZNIFHPLKGYRTM-UHFFFAOYSA-N

InChI=1S/C15H10O5/c16-9-3-1-8(2-4-9)13-7-12(19)15-11(18)5-10(17)6-14(15)20-13/h1-7,16-18H

5,7-dihydroxy-2-(4-hydroxyphenyl)chromen-4-one

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Solubility in Formulation 1: ≥ 2.08 mg/mL (7.70 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 2.08 mg/mL (7.70 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.

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Solubility in Formulation 3: 10 mg/mL (37.00 mM) in 0.5% CMC-Na/saline water (add these co-solvents sequentially from left to right, and one by one), suspension solution; with ultrasonication.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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 (Please use freshly prepared in vivo formulations for optimal results.)