Casticin

Other Names

3',5-Dihydroxy-3,4',6,7-tetramethoxyflavone3,4',6,7-Tetra-O-methylquercetagetin3,4',6,7-Tetramethoxy-3',5-dihydroxyflavone3,6,7,4'-Tetra-O-methyl-5,3'-dihydroxyflavone3,6,7,4'-Tetramethylquercetagetin4H-1-Benzopyran-4-one, 5-hydroxy-2-(3-hydroxy-4-methoxyphenyl)-3,6,7-trimethoxy-5,3'-Dihydroxy-3,6,7,4'-tetramethoxyflavone5-Hydroxy-2-(3-hydroxy-4-methoxy-phenyl)-3,6,7-trimethoxy-chromen-4-one5-Hydroxy-2-(3-hydroxy-4-methoxyphenyl)-3,6,7-trimethoxy-4H-1-benzopyran-4-one5-Hydroxy-2-(3-hydroxy-4-methoxyphenyl)-3,6,7-trimethoxy-4H-benzopyran-4-one, 9CI5-Hydroxy-2-(3-hydroxy-4-methoxyphenyl)-3,6,7-trimethoxy-4H-chromen-4-one5-Hydroxy-2-(3-hydroxy-4-methoxyphenyl)-3,6,7-trimethoxychromen-4-oneCasticin (6CI)CasticineQuercetagetin 3,4',6,7-tetramethyl etherQuercetagetin 3,6,7,4'-tetramethyl etherVitexicarpinVx-5 Cpd

Synopsis

Casticin: A Comprehensive Encyclopedic Reference

1. Identity and Chemical Characterization

Chemical Names and Identifiers

Casticin has the IUPAC name 5-hydroxy-2-(3-hydroxy-4-methoxyphenyl)-3,6,7-trimethoxychromen-4-one, with the molecular formula C₁₉H₁₈O₈ and CAS registry number 479-91-4. It is also known by the synonym vitexicarpin and is classified as a tetramethoxyflavone with a molecular weight of 374.34 g/mol. It is a solid with a melting point of 186°C–187°C and a solubility of approximately 120.7 mg/L at 25°C.

The full systematic chemical name is 3′,5-dihydroxy-3,4′,6,7-tetramethoxyflavone, reflecting the presence of two free hydroxyl groups and four methoxy substituents on the flavone backbone. Structurally, casticin is a polymethylflavone with three rings, an orthocatechol moiety, a double bond, two hydroxyl groups, and four methoxyl groups. Because the core flavonoid structure carries methyl groups at multiple positions, it is classified as a methoxylated flavonol.

Casticin is also named Vitexicarpin and has been characterized as a major flavone component isolated from medicinal plants of the Vitex species, including Vitex trifolia L. and Vitex agnus-castus L. It appears in the European Pharmacopoeia as an analytical reference standard. Casticin appears as a marker compound in European Pharmacopoeia Monograph 2147 (Chaste Tree Fruit, 2008) and Monograph 2309 (Agnus Castus Fruit Dry Extract, 2015), as well as in the American Herbal Pharmacopoeia Valerian Root monograph (1999).

Botanical Sources

Casticin is a major bioactive flavonoid isolated from several plants, mainly from the Vitex species. Casticin has been isolated from various tissues of plants in the Vitex genus: fruits and leaves of V. trifolia, aerial parts and seeds of V. agnus-castus, and leaves of V. negundo. It is a flavonoid characteristic of Vitex spp., from which it has been isolated from leaves, fruits, and seeds. Its concentration in V. agnus-castus fruits varies from 0.03% to 1.18%, while in V. trifolia leaves, it is present at approximately 0.01%.

Casticin has also been isolated from a range of other plant species beyond Vitex, including Psiadia trinervia, Tessaria fastigiata, Pluchea quitoc, Crataegus pinnatifida, Clausena excavata, Achillea millefolium (yarrow), Laggera alata, Croton betulaster, Daphne genkwa, Artemisia annua (sweet wormwood), and Tanacetum sinaicum. The flavonoid found in Artemisia annua has been shown to enhance the antimalarial activity of artemisinin, though casticin itself has no direct antimalarial effects.

One study confirmed that casticin extracted from Achillea millefolium L. fights tumors by stopping cell growth in the G2/M phase and triggering cell death. In Artemisia annua, casticin belongs to the group of polymethoxylated flavonoids that are more efficiently extracted with low polarity solvents such as dichloromethane rather than polar media like water.

Common Preparations and Dosage Forms

Casticin is not typically marketed as an isolated compound in dietary supplements. Rather, it is encountered primarily as a constituent of whole-plant or standardized extracts of Vitex agnus-castus (chasteberry) or Vitex rotundifolia (Fructus Viticis), which are available in the forms of:

Standardized fruit dry extract capsules or tablets (standardized to casticin and/or agnuside content)
Hydroethanolic fruit extracts (tinctures)
Powdered dried fruit preparations
Isolated casticin as a research-grade analytical standard (≥98% purity by HPLC)

Medicinal products showed a very similar HPLC profile, though health foods showed a variety of profiles with large peak differences; the contents of agnuside and casticin in traditional medicinal products were very low compared to those in well-established medicinal products. Some health foods showed a higher ratio of agnuside to casticin, which resembles that of Vitex negundo L., a related Chinese herb.

2. Traditional and Historical Use

Ancient Mediterranean and European Traditions

The parent plant, Vitex agnus-castus (VAC), a member of the family Lamiaceae, is a deciduous tree or large shrub native to central Asia and Mediterranean Europe, also known as chaste tree, chasteberry, or monk's pepper. The dried fruits have been used for more than 2,500 years for medicinal purposes, mostly for a variety of gynaecological conditions.

The shrub was utilized for religious rituals in ancient Greece and among the Philistines in Palestine as well as other countries in the Levant region. Its macaronic specific name agnus-castus repeats "chaste" in both Greek and Latin; the small tree was considered to be sacred to the virginal goddess Hestia/Vesta.

Historical documents reference Vitex agnus-castus as early as the 1st century CE in Dioscorides' "De Materia Medica," where it was noted for promoting chastity among convent nuns. In ancient Greece, women chewed leaves or made wine infusions of the berries during festivals to reduce libido and enhance focus. Roman physicians, including Pliny the Elder, recommended it for menstrual irregularities and mastitis, and medieval herbalists in Europe continued the tradition, calling it "monk's pepper."

Traditional Chinese Medicine

Casticin is a primary component of the fruits of Vitex rotundifolia L. (known as Fructus Viticis or Manjingzi in Chinese), which has been used for thousands of years as an anti-inflammatory agent in Traditional Chinese Medicine. Casticin has been identified as one of the major flavonoids in Fructus Viticis extracts, which were often used in traditional treatment methods for various pains such as migraine, chronic headaches, and eye pain. In Chinese traditional medicine, Vitex preparations are used as anti-inflammatory agents.

Ayurveda, Unani, and Other Asian Traditions

The Vitex plant has been known and used as herbal medicine across many traditions, where it was recognized and noted in many health practices, including Ayurveda, Unani medicine, Chinese traditional medicine, Malay traditional medicine, European medicine, and ancient Greek medicine. These traditions mention the use of Vitex for a wide range of conditions, such as treating women with reproductive disorders, improving body health after childbirth, suppressing libido, treating skin problems, curing symptoms of gastrointestinal afflictions, reducing fever, and healing rheumatism.

The berries are rich in iridoids such as agnuside and aucubin, flavonoids including casticin, and volatile oils. In these traditions, the dried fruits were the primary medicinal part, administered as decoctions, powders, or infusions in water or wine.

3. Key Constituents and Active Compounds in the Plant Matrix

While casticin is the subject of this article, it is important to understand its chemical context within the plants from which it derives. In Vitex agnus-castus fruits, casticin co-occurs with numerous other bioactive compounds. Other constituents identified from V. agnus-castus fruits alongside casticin include labdane-type diterpenoids (vitexilactone, rotundifuran, and 8-epi-manoyl oxide), flavonoids (luteolin-7-O-glucoside, 5-hydroxy-3,6,7,4′-tetramethoxyflavone, and artemetin), iridoid glycosides (aucubin and agnuside), a sterol (β-sitosterol), and simple phenolics (p-hydroxybenzoic acid).

As a bioactive flavonoid, casticin belongs to the chemical group of flavonoids, which includes polyphenolic properties related to phenolic acids, stilbenes, and related polyphenols. Based on structural classification, casticin is included in the subfamily of flavonols.

4. Mechanisms of Action

Anti-inflammatory Mechanisms

In a study using IL-1β–activated A549 human pulmonary epithelial cells, casticin decreased levels of IL-6, tumor necrosis factor-α, and IL-8, and suppressed COX-2 expression and prostaglandin E2 production. It also reduced MUC5AC, pro-inflammatory cytokine, and chemokine gene expression, and inhibited ICAM-1 expression for monocyte adhesion. In addition, casticin inhibited phosphorylation of Akt, PI3K, and MAPK, and blocked NF-κB subunit p65 protein translocation into the nucleus.

From Vitex rotundifolia fruits, casticin was found to inhibit the levels of nitric oxide and PGE2 as well as decrease the production of IL-1β, IL-6, and TNF-α. Various concentrations of casticin ranging from 0.3 to 10 μM were used to treat RAW264.7 cells with LPS-induced inflammation, and the molecular mechanism suggested this activity was due to the inhibition of proinflammatory interleukins by blocking the NF-κB and Akt pathways.

Casticin also suppressed leukocyte adherence to lung epithelial cells by reducing ICAM-1 expression via inhibition of the IL-1β pathway, suggesting potential as a natural anti-inflammatory agent in inflammatory lung disease.

Anticancer Mechanisms

Casticin inhibits invasion, migration, and proliferation, and induces apoptosis (casticin-induced, ROS-mediated, and mitochondrial-dependent) and cell cycle arrest (G0/G1, G2/M) through multiple signaling pathways, namely the PI3K/Akt, NF-κB, STAT3, and FOXO3a/FoxM1 pathways.

Furthermore, casticin affects diverse oncogenic pathways such as the MAPK, NF-κB, and PI3K/Akt pathways through the modulation of various proteins; increases ROS generation through the enhancement of Bax proteins and the decrease of Bcl proteins; and inhibits cell division cycle proteins (cdc25c and cdc2) and cyclins (B1) to induce cell cycle arrest.

Additionally, casticin induces mitochondrial apoptosis by the upregulation of cytochrome c, the downregulation of mitochondrial membrane potential (MMP), and an increase in caspase-3 and -9 activities; Bax is upregulated while Bcl-xL and XIAP are both downregulated.

Casticin-induced apoptotic cell death is accompanied by the activation of the transcription factor FOXO3a, with a concomitant decrease in the expression levels of FoxM1 and its downstream target factors, namely survivin and polo-like kinase 1 (PLK1), and an increase in p27KIP1.

Casticin has also been shown to inhibit the activation of STAT3, a transcription factor frequently overactivated in cancers. It also exhibits anti-mitotic activity.

Hormonal and Prolactin-Inhibiting Mechanisms

In animal studies, casticin inhibited the release of prolactin from pituitary cells of rats stimulated with estradiol (E2) in vivo and in vitro. These effects were associated with inhibiting ERα mRNA expression and increasing ERβ mRNA expression in pituitary cells.

Immunomodulatory Mechanisms

Casticin, isolated from the aerial parts of Vitex agnus-castus, was found to be a potent immunomodulatory and cytotoxic compound. The activity was tested in vitro for chemiluminescence, chemotaxis, T-cell proliferation, and cytotoxicity. Casticin exhibited a significant inhibitory effect on monocyte oxidative burst in a dose-dependent manner. It was found to have a significant suppressive effect on the chemotaxic action at higher concentrations on fMLP-stimulated neutrophils. It also showed a potent suppressive effect on PHA-stimulated T-cell (PBMC) proliferation.

Anti-fibrotic Mechanisms

The molecular mechanism underlying casticin's effect on liver fibrosis involves inhibition of hepatic stellate cell (HSC) activation and reduced expression of matrix metalloproteinase (MMP)-2, MMP-9, tissue inhibitor of metalloproteinases (TIMP)-1, and TIMP-2, resulting from blocking TGF-β1/Smad signaling, as well as increased apoptosis of HSCs.

5. Scientific Evidence by Area of Use

5.1 Oncology (Anticancer Activity)

Casticin, extracted from the Vitex species and isolated from the leaves and seeds of V. trifolia and V. agnus-castus, possesses a wide range of therapeutic properties including analgesic, anti-inflammatory, antiangiogenic, antiasthmatic, and antineoplastic activities. Several studies have been conducted on its anticancer effects against cancers including breast, bladder, oral, lung, leukemia, and hepatocellular carcinomas.

Leukemia: Casticin decreases proliferation in K562, HL-60, and Kasumi-1 leukemia cell lines, with IC₅₀ values of 5.95, 4.82, and 15.56 μM, respectively.

Ovarian Cancer: In a study of human ovarian cancer cell lines SKOV3 and A2780 cultured in vitro, casticin elicited a marked effect on apoptosis, as demonstrated by histone/DNA ELISA results showing activation of caspase-3 and cleavage of PARP, accompanied by the downregulation of FoxM1 expression. Knockdown of FOXO3a by siRNA blocked the casticin-induced down-regulation of FoxM1 expression and inhibited ovarian cancer cell apoptosis, indicating that FOXO3a is a key regulator of casticin-induced apoptosis and FoxM1 expression in ovarian cancer cells.

Colon Cancer: In human colon cancer cells (HT-29, HCT-116, SW480, and Caco-2), casticin significantly induced apoptosis, induced the accumulation of reactive oxygen species (ROS), and increased the protein levels of ASK1, JNK, and Bim. Pretreatment with N-acetylcysteine, an antioxidant, inhibited this casticin-induced apoptosis. Small interfering RNA targeting ASK1 significantly attenuated the JNK and Bim activation and apoptotic cell death. The results suggest casticin significantly induced apoptosis by the activation of the ASK1-JNK-Bim signaling cascade and accumulation of ROS in colon cancer cells.

Esophageal Cancer: In in vitro studies using human esophageal cancer cell lines TE-1 and ECA-109 treated with various concentrations of casticin, results showed that casticin dose-dependently inhibited the proliferation and clonogenicity of EC cells and induced cell cycle arrest in sub-G1 and G2 phases. Casticin markedly enhanced EC cell apoptosis as detected by flow cytometry and Hoechst 33342 staining. The level of anti-apoptotic Bcl-2 protein was decreased, while levels of pro-apoptotic Bax, cleaved-caspase-3, cleaved-caspase-9, and cleaved-PARP were conversely increased in casticin-treated cells.

Gallbladder Cancer: Casticin, extracted from Vitex rotundifolia L., significantly inhibited gallbladder cancer cell proliferation in a dose- and time-dependent manner in human NOZ and SGC996 cells.

Nasopharyngeal Carcinoma: Many studies have reported that casticin can significantly inhibit the proliferation and migration of many types of cancer cells, including leukemia cells and ovary, stomach, liver, lung, and colon cancer cells. Previous studies have indicated that there are many mechanisms involved in the apoptosis of cancer cells in response to casticin, including caspase-3 activation, G2/M phase arrest, activation of FoxO3a, and activation of PI3K/Akt.

Anticancer activity against normal cells: Although casticin has displayed strong cytotoxic activities towards cancerous cells in preclinical studies, pretreatment with casticin did not result in apoptosis or necroptosis of normal cells.

Evidence strength: All anticancer evidence is currently preclinical only — derived from in vitro cell line studies and in vivo animal (mouse) models. The antineoplastic potential of casticin has attracted scientific attention for its ability to target multiple cancer pathways, and the purpose of recent reviews is to critically analyze this potential and highlight the molecular pathways underlying its antitumor effects. No human clinical trials evaluating casticin as a cancer treatment have been published as of the date of this article.

5.2 Anti-inflammatory Effects

In mouse models, administration of casticin (0.5, 1, and 1.5 μmol/cm²) inhibited croton oil-induced ear edema, a standard model of cutaneous inflammation. In HT-29/NF-κB-luc cells, casticin inhibited NF-κB activation in the presence of LPS.

Casticin, isolated from Vitex trifolia, has been shown to have anti-inflammatory and antitumor effects in previous studies. In a murine model of destabilization of the medial meniscus (DMM) for osteoarthritis, male BALB/c mice were randomly divided into groups including a DMM-induced OA group treated with casticin.

Evidence strength: The anti-inflammatory evidence for casticin as an isolated compound is preclinical only (in vitro and animal models). The parent plant extract (V. agnus-castus) has clinical evidence for related indications, but studies specifically measuring casticin's contribution to this activity in humans are lacking.

5.3 Hyperprolactinemia and Hormonal Modulation

The anti-hyperprolactinemia activity of casticin, isolated from Vitex rotundifolia, and its molecular mechanism have been investigated. In this research, hyperprolactinemia was induced by administration of metoclopramide dihydrochloride (50 mg/kg, tid, ip, for 10 days) in SD rats, and prolactin concentrations were measured using a radioimmunoassay. CAS10, CAS20, and CAS40 — doses of casticin at 10, 20, and 40 mg/kg, respectively — were evaluated for their effects on prolactin levels expressed as a percentage of production by controls in pituitary cells.

In the last century, V. agnus-castus has been mostly used for the treatment of premenstrual syndrome (PMS), menstrual irregularities, fertility disorders, and symptoms of menopause. Since some degree of hyperprolactinaemia may be observed in patients with such disorders, VAC effects on hyperprolactinaemia have been assessed in a small number of studies and some patient series. It has been postulated that the diterpenes contained in VAC extract may interact with dopamine D2 receptors (D2R) and inhibit prolactin release via dopamine D2R activation in the anterior pituitary.

Evidence strength: Prolactin-inhibiting activity of casticin specifically (as distinct from the whole plant extract) is demonstrated only in animal models. Clinical trials on V. agnus-castus extract have shown effects on PMS and prolactin, but casticin's individual contribution cannot be separated from other plant constituents in these human trials. Among Vitex species, Vitex agnus-castus L. is the only one that has undergone clinical trials, mainly related to mastalgia, menstrual bleeding problems, amenorrhea, menorrhagia, luteal insufficiency, and premenstrual syndrome — all using whole plant extracts, not isolated casticin.

5.4 Hepatoprotection and Liver Fibrosis

In one study, the antifibrotic activity of casticin and its underlying mechanism were investigated in vivo and in vitro. Male mice were injected intraperitoneally with carbon tetrachloride (CCl4) or underwent bile duct ligation (BDL) to induce liver fibrosis, followed by treatment with casticin or vehicle. In addition, TGF-β1-activated LX-2 cells were used. In vivo experiments showed that treatment with casticin alone had no toxic effect, while significantly attenuating CCl4- or BDL-induced liver fibrosis, as indicated by reductions in the density of fibrosis, hydroxyproline content, and expression of α-SMA and collagen α1(I) mRNA.

Moreover, casticin inhibited LX2 (hepatic stellate cell) proliferation and induced apoptosis in a time- and dose-dependent manner in vitro. The results suggest that casticin has potential benefits in the attenuation and treatment of liver fibrosis.

Casticin also blocks TGF-β/SMAD signaling in LX2 cells, preventing activation, inhibiting proliferation, and inducing apoptosis of these hepatic stellate cells. In a mouse model of liver fibrosis, casticin (20 mg/kg) decreases TGF-β1 mRNA and phosphorylated SMAD (p-SMAD) levels.

Evidence strength: Preclinical only — in vitro and murine in vivo models. No clinical studies in humans.

5.5 Immunomodulation

Casticin exhibits significant immunomodulatory capacities that modulate cytokine expression and immune cell function. In isolated in vitro testing, casticin was found to suppress monocyte oxidative burst, inhibit neutrophil chemotaxis, and inhibit T-cell proliferation. It exhibits anti-inflammatory behavior in part through its inhibitory effect on lipoxygenases and T- and B-lymphocytes.

Evidence strength: Preliminary, in vitro only.

5.6 Antimalarial Synergy

Casticin (5,3′-dihydroxy-3,6,7,4′-tetramethoxyflavone), present in the whole plant of Artemisia annua, has been shown to markedly enhance the antimalarial activity of artemisinin. Casticin has been identified as one of the possible synergistic compounds found in antimalarial tea preparations from A. annua, with an in vitro IC₅₀ against Plasmodium of 24 μmol/L — though this is much higher than the IC₅₀ of artemisinin (0.03 μmol/L) itself. A number of flavonoids including casticin and artemetin from Artemisia annua have shown synergism with artemisinin against Plasmodium falciparum, but it remains unclear whether the flavonoids are actually extracted into a tea infusion of the plant in significant quantities.

Evidence strength: Preliminary, in vitro only. The concentrations needed to demonstrate synergy in vitro are unlikely to be achievable through oral delivery under physiological conditions, as noted in the primary literature.

5.7 Metabolic Effects (Antidiabetic/Lipid)

Casticin exhibits significant antidiabetic properties through enhanced glucose metabolism and insulin sensitivity, along with immunomodulatory capacities that modulate cytokine expression and immune cell function. It reduces intracellular lipid accumulation in differentiated adipocytes. Casticin has an additional hydroxyl group at the 3' position compared to its counterpart 5-OH nobiletin, which results in the direct suppression of cell growth and lipogenesis.

Evidence strength: Preliminary, in vitro only. No clinical studies specific to casticin as an isolated compound for metabolic disorders have been published.

5.8 Organ-Protective Effects

The scientific literature highlights casticin's organ-protective potential, including neuroprotective, cardioprotective, hepatoprotective, nephroprotective, pulmonary, and testicular cytoprotection. Casticin has been reported to have a wide array of pharmacological roles, including immunomodulatory, antihyperprolactinemia, antitumor, and neuroprotective effects. It showed anti-inflammatory effect in rat macrophages via inhibition of nitric oxide, COX-2, prostaglandin E2, IL-1β, IL-6, and TNF-α.

Evidence strength: For most of these organ-protective effects, evidence is preclinical only — animal models and in vitro data. No robust human clinical trial data exist.

6. Pharmacokinetics and Bioavailability

In a pharmacokinetic study using liquid chromatography–mass spectrometry, casticin was studied after oral and intravenous administration to rats, and the absolute bioavailability was determined to be 45.5 ± 11.0%. The method revealed a moderate oral bioavailability of 45.5 ± 11.0% with high sensitivity (LLOD of 7 ng/mL) and linearity (r > 0.9996), and a recovery range of 91–102%. Casticin's detectability after intravenous administration supports its potential suitability for non-oral delivery.

Pharmacokinetic analysis, supported by network pharmacology and in vitro validation, revealed significant differences between aqueous and ethanolic formulations of casticin-containing plant extracts and linked absorbed casticin to 32 molecular pathways, including 15 cancer-related pathways.

Casticin demonstrates poor aqueous solubility (LogS = −4.077), which is consistent with its polymethoxylated structure and its better extraction with less polar solvents such as dichloromethane. Its molecular weight is 374.1 Da, which falls within Lipinski's Rule of Five for drug-likeness. No human pharmacokinetic data for isolated casticin have been published in the available literature.

A lower limit of quantification (LLOQ) of 0.5 ng/mL in rat plasma was reported following ethanolic Vitex extract administration.

7. Dosages Reported in Research Studies

The following dosages appear in peer-reviewed preclinical studies. No clinical trials establishing a specific dose for casticin as an isolated compound in humans have been published.

Anti-hyperprolactinemia (rat in vivo): Casticin at doses of 10, 20, and 40 mg/kg (referred to as CAS10, CAS20, and CAS40) was evaluated for effects on prolactin levels in a metoclopramide-induced hyperprolactinemia rat model.
Anti-inflammatory in vitro (lung epithelial cells): A549 cells were treated with various concentrations of casticin (5–20 μM) alongside IL-1β cytokine challenge.
Anti-inflammatory in vitro (macrophages): Various concentrations of casticin ranging from 0.3 to 10 μM were used to treat RAW264.7 cells with LPS-induced inflammation.
Liver fibrosis (mouse in vivo): In a mouse model of liver fibrosis, casticin was administered at 20 mg/kg, resulting in decreased TGF-β1 mRNA and phosphorylated SMAD levels.
Cutaneous inflammation (mouse in vivo): Administration of casticin at 0.5, 1, and 1.5 μmol/cm² inhibited croton oil-induced ear edema.
Leukemia cells (in vitro): Casticin decreases proliferation in K562, HL-60, and Kasumi-1 leukemia cell lines at IC₅₀ values of 5.95, 4.82, and 15.56 μM, respectively.

8. Body Systems and Health Areas

Research has implicated casticin across multiple body systems and health domains:

Endocrine/Reproductive: Prolactin inhibition, estrogenic receptor modulation, PMS and menstrual cycle support (via parent plant extracts)
Oncology: Studied against cancers including breast, bladder, oral, lung, leukemia, and hepatocellular carcinomas.
Hepatic: Hepatoprotection and attenuation of liver fibrosis via TGF-β/Smad signaling
Pulmonary: Anti-inflammatory effects in airway epithelial cells
Musculoskeletal: Osteoarthritis cartilage protection via ROS-mediated NF-κB inhibition
Immunological: Modulation of T-cell proliferation, neutrophil chemotaxis, and monocyte oxidative burst
Metabolic: Preliminary evidence for antidiabetic properties and anti-adipogenic effects
Neurological: Neuroprotective effects noted in review literature, though specific human data are absent.
Antimicrobial: Broad-spectrum antimicrobial effects including antibacterial, antiviral, and antifungal activities have been reported in vitro.

9. Safety Considerations

Preclinical Toxicity Data

In vivo experiments in mice showed that treatment with casticin alone had no toxic effect while significantly attenuating liver fibrosis. Specifically, treatment with casticin alone for two weeks had no toxic effect on the liver, demonstrating a hepatoprotective effect.

Ames test predictions indicate low mutagenic potential across casticin and related Vitex compounds (≤82.4%), and carcinogenicity assessments suggest minimal concern, supporting their safety profiles for long-term therapeutic use based on computational modeling. It must be noted that these are computational (in silico) ADMET predictions, not human toxicological studies.

Although casticin has displayed strong cytotoxic activities towards cancerous cells in preclinical studies, pretreatment with casticin did not result in apoptosis or necroptosis of normal cells, suggesting some degree of selectivity toward cancer cells in preclinical models.

Solubility and Bioavailability Limitations

Casticin demonstrates poor aqueous solubility (LogS = −4.077), which may limit its oral absorption in non-formulated forms. This has practical implications for supplement preparations and dosing. The significantly better extraction of casticin with low-polarity solvents compared to water means that aqueous preparations (such as teas) of Artemisia annua or Vitex may deliver much lower amounts of casticin than hydroethanolic or ethanolic extracts. It remains unclear whether casticin is actually extracted into a tea infusion of Artemisia annua in significant quantities.

Interactions and Broader Safety Gaps

Casticin as an isolated compound has not been evaluated in formal human clinical safety or interaction studies. Pharmacokinetic analysis has linked absorbed casticin to 32 molecular pathways, including 15 cancer-related pathways, which raises theoretical concerns about interactions with drugs relying on overlapping signaling pathways (e.g., PI3K/Akt inhibitors, NF-κB modulators), though no specific clinical interaction data for casticin alone have been published. No specific cytochrome P450 interaction data for isolated casticin have been located in the peer-reviewed literature at the time of this article.

Comprehensive information on casticin's pharmacological features, coupled with its potential as a medicine, is considered critical for further development, including definition of pharmacological goals, safety and toxicity profiling, and development as a natural product drug. Researchers have explicitly noted the absence of human pharmacokinetic data.

Pregnancy and Hormonal Cautions (Parent Plant Context)

Casticin-containing plant extracts (particularly Vitex agnus-castus) have known hormonal activity — specifically dopaminergic and estrogenic actions — and clinical use of the whole plant in pregnant women or those on hormonal therapies is generally avoided in practice. While these observations pertain to the whole plant, casticin's demonstrated estrogenic receptor modulation and prolactin-suppressing effects suggest that similar biological cautions may logically apply, though this has not been formally studied for casticin as an isolated compound in clinical populations.

10. Current Research Status and Limitations

Casticin's bioavailability, pharmacokinetics, and synergistic potential with other therapeutics further support its promise as a multi-targeted natural compound, and current research underscores its broad pharmacological spectrum and encourages future research into clinical applications.

The direct molecular targets of casticin are still not fully determined, which limits its clinical applications. The overwhelming majority of evidence supporting the biological activities of casticin comes from cell culture (in vitro) experiments and animal models. Translating these findings to human clinical benefit requires:

Well-designed, adequately powered clinical trials in humans
Human pharmacokinetic studies establishing plasma concentrations achieved at safe doses
Clarity on whether in vitro concentrations are achievable in humans without toxicity
Standardization of casticin content in botanical preparations used in any trial

Clinical trials and commercial use of the casticin-rich fruit extract of V. agnus-castus among women with premenstrual syndrome have been discussed in review articles, but these trials use standardized whole-plant extracts, not isolated casticin, making it impossible to attribute clinical outcomes solely to casticin.

References

Health Conditions

Health conditions that Casticin may help support.

PMSTraditional
Casticin is a polymethoxylated flavone constituent of Vitex agnus-castus fruit, one of the bioactive compounds in chasteberry extracts used for PMS. It has documented anti-inflammatory and anti-proliferative properties in preclinical studies, contributing to the overall mechanism of action of Vitex preparations for PMS.

Body Systems

Body systems that Casticin may help support.

No body systems available.