IngredientsWogonin (5,7-dihydroxy-8-methoxyflavone) is a flavonoid originating from the root of the medicinal herb Scutellaria baicalensis Georgi. Chemically, it is an O-methylated flavone, a flavonoid-like compound. It has the molecular weight of 284.267 g/mol and is a crystalline solid with maximum solubility in organic solvents and limited aqueous solubility.
Wogonin, a naturally occurring plant flavonoid, is isolated from the Chinese herbal plants Scutellaria baicalensis Georgi and S. barbata D. Don. Scutellaria baicalensis, with the common name Baikal skullcap or Chinese skullcap, is a species of flowering plant in the family Lamiaceae, native to China, Korea, Mongolia, and Russia in the Russian Far East and Siberia.
The glycosides of wogonin are known as wogonosides. For example, oroxindin is a wogonin glucuronide isolated from Oroxylum indicum. Significant active constituents found in the plant's root include flavonoids and flavonoid glycosides, such as wogonin, baicalein, baicalin, oroxylin A, scutellarein, and norwogonin.
Wogonin is one of the active ingredients of Sho-Saiko-To, a Japanese herbal supplement. Methods for its extraction from herbs and its chemical synthesis have been developed. It can be extracted from plants and can also be prepared by chemical synthesis in industry.
Scutellaria baicalensis Georgi has been listed in the Chinese Pharmacopeia, the Japanese Pharmacopeia, the Korean Pharmacopoeia, and the European Pharmacopoeia. The Chinese Pharmacopeia has adopted the content of baicalin, a flavonoid compound, as a quality control standard for Scutellaria baicalensis Georgi.
Scutellaria baicalensis Georgi, or Chinese skullcap, has been widely used as a medicinal plant in China for thousands of years, where the preparation from its roots is called Huang-Qin. It has been applied in the treatment of diarrhea, dysentery, hypertension, hemorrhaging, insomnia, inflammation, and respiratory infections.
Scutellaria baicalensis has been used by Chinese people for more than 2,000 years. It is known as Huang-Qin in the traditional Chinese medicine system and is now listed officially in the Chinese Pharmacopoeia. Its first mention in Chinese Materia Medica (herbals) comes in the Shen Nong Ben Cao Jing, where it appears in the middle class of drugs.
Scutellariae radix is the dried root of Scutellaria baicalensis Georgi. It has a long history of ethnic medicinal use, traditionally recognized for its efficacy in clearing heat, drying dampness, eliminating fire, removing toxins, stopping bleeding, and tranquilizing the fetus to prevent miscarriage. Clinically in traditional practice, it has been used to treat cold, fever, migraine, hand-foot-and-mouth diseases, liver cancer, and inflammatory diseases.
The plant is one of the 50 fundamental herbs used in traditional Chinese medicine, where it has the name huángqín (黄芩). Its use in TCM has been for "the prophylaxis and treatment of hepatitis, atherosclerosis, hypertension, hyperlipidemia, type 2 diabetes, dysentery, ulcerative colitis, and respiratory disorders."
The dried root of Huang-Qin is often prepared by decoction (boiling) or as tinctures. The extract of S. baicalensis Georgi has been added to an assortment of health drinks or food supplements.
The plant was first described in Western botanical terms by German-born botanist Johann Gottlieb Georgi (1729–1802), a professor of the Russian Academy of Sciences in St. Petersburg — hence the epithet Georgi in the plant's scientific name. Scutellaria baicalensis (Huang-Qin) is a traditional herb that has been historically diversified and used culturally in Chinese medicine.
Chinese native medicine Scutellaria baicalensis Georgi, also referred to as Chinese skullcap or Huang-Qin, is frequently used to treat cancer, viral infections, and seizures, with this plant's abundance of flavones (wogonoside) and their related aglycones (wogonin) being responsible for many of its pharmacological effects. The roots and their preparations have also been documented in the Japanese Pharmacopeia and the Korean Pharmacopoeia, reflecting long-standing use in those traditions. Wogonin is one of the active ingredients of Sho-Saiko-To, a Japanese herbal supplement.
Since the late 1970s, over 40 different polyphenols, including various forms of flavonoids such as flavonols, dihydroflavonoids, and chalcones, as well as flavonoids themselves, have been isolated and identified from Scutellaria baicalensis Georgi. The most representative components of these polyphenols are baicalin, baicalein, wogonoside, and wogonin, which have been extensively studied for their potential beneficial effects.
Flavones such as baicalin, wogonoside, and their aglycones baicalein and wogonin are the major bioactive compounds extracted from the root of S. baicalensis. Among these, wogonin is the aglycone form; its glycoside (glucuronide) counterpart in the plant is wogonoside. This plant's abundance of flavones (wogonoside) and their related aglycones (wogonin) is responsible for many of its pharmacological effects.
Wogonin carries a unique 8-methoxy group that distinguishes it from other closely related skullcap flavonoids. The extract of Scutellariae radix and its main flavonoids such as baicalin, baicalein, wogonin, wogonoside, and scutellarin show antioxidant activity, among other pharmacological effects.
The anti-inflammatory activity of wogonin likely involves suppression of iNOS induction and COX-2 expression, consequently inhibiting nitric oxide synthesis and prostaglandin E2 production. Wogonin inhibits phorbol ester-induced COX-2 protein and mRNA levels in human lung epithelial cancer cells, and this inhibition operates at the transcriptional level; the MEK1/2 signaling pathway plays a critical role in this process. Wogonin also inhibits AP-1 activation and the expression of c-Jun, a key component of AP-1, thereby inhibiting COX-2 gene expression.
A staggering amount of literature correlates wogonin with the inhibition of NF-κB expression levels and activation in vivo and in vitro, and wogonin potentially acts as a reactive oxygen species (ROS) scavenger that reduces NF-κB activation and the general inflammatory response.
It has been shown experimentally that wogonin exerts antioxidant activity, which may, in part, underlie its anti-inflammatory, anti-cancer, antiviral, and neuroprotective actions.
Wogonin (5,7-dihydroxy-8-methoxyflavone), one of the major flavonoids isolated from the root of Scutellaria baicalensis Georgi, is considered a promising anticancer candidate due to its antiproliferating, apoptosis-inducing, angiogenesis-inhibiting, cell-migration-inhibiting, and differentiation-inducing activities.
Wogonin has been shown to inhibit the growth of tumor cells, induce apoptosis, and suppress angiogenesis, with molecular mechanisms involving reactive oxygen species, Ca²⁺, NF-κB, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), and tumor necrosis factor-alpha.
In breast cancer cells, wogonin induces mitochondria and death-receptor-mediated apoptotic cell death, characterized by activation of several caspases, induction of PARP cleavage, changes in antiapoptotic/pro-apoptotic Bcl-2 family member ratios, and cleavage of Bid. Generation of ROS was found to be an important mediator in wogonin-induced apoptosis, with wogonin also activating ERK and p38 MAPKs in a ROS-dependent manner.
Wogonin's anticancer effects are supported by its ability to regulate a variety of oncogenic and tumor-suppressive signaling pathways, particularly PI3K/Akt, STAT3, NF-κB, MAPK, AMPK, and Wnt/β-catenin. It modulates apoptosis-related proteins including Bax, Bcl-2, PARP, and caspases, as well as relevant transcription factors.
Wogonin has also been studied to pharmaceutically target proteins such as JAK/STAT, VEGF/VEGFR, Wnt/β-catenin, and TRAIL-mediated cell death in many cancerous cells.
Wogonin inhibits inflammatory activation of cultured brain microglia by diminishing lipopolysaccharide-induced TNF-α, interleukin-1β, and nitric oxide production. It inhibits NO production by suppressing inducible NO synthase (iNOS) induction and NF-κB activation in microglia. Wogonin exerts its neuroprotective effect by inhibiting microglial activation, which is a critical component of pathogenic inflammatory responses in neurodegenerative diseases.
The pharmacological properties of wogonin at the benzodiazepine site (BZD-S) on the γ-aminobutyric acid A (GABAA) receptor complex show an affinity (Ki) of 0.92 μM. Using electrophysiological techniques, wogonin was shown to enhance the GABA-activated current in rat dorsal root ganglion neurons, and in oocytes expressing recombinant rat GABAA receptors, this enhancement was partially reversed by co-application of the BZD-S antagonist anexate (Ro15-1788).
Wogonin targets the site on GABAA located at the γ2 subunit, and its anxiolytic property is strongly linked to the BZD-site.
Wogonin from Scutellaria baicalensis significantly suppressed HBsAg (hepatitis B surface antigen) expression in a dose-dependent manner in the hepatocellular cell line MS-G2. Multiple preclinical reports have also documented activity against respiratory syncytial virus in vitro.
Wogonin, as one major active constituent of Scutellariae radix, has been reported to play an important role in anti-inflammatory, anti-cancer, anti-viral, anti-angiogenesis, antioxidant, and neuroprotective effects. Anti-fibrotic effects in the liver have also been investigated, with studies evaluating its protective role in liver fibrosis.
Important overarching note on evidence quality: Results for wogonin in terms of antitumoral, neuroprotective, anti-inflammatory, and antiviral activity stress its efficacy and safety and encourage further work. However, to the best of the available review literature, no clinical trials have been conducted so far on this molecule as an isolated compound. The great majority of evidence for wogonin as an isolated compound is therefore derived from in vitro (cell culture) and in vivo (animal model) studies.
Numerous preclinical investigations have revealed that wogonin suppresses tumor growth by cell cycle arrest, stimulating cell death, and preventing metastasis. Cancer types investigated in preclinical models include leukemia, hepatocellular carcinoma, breast cancer, bladder cancer, lung adenocarcinoma, colorectal cancer, and others.
Evidence assessment: All available anticancer evidence for wogonin as an isolated compound is preclinical (in vitro cell-line studies and animal models). Although the safety record of wogonin is remarkable and a voluminous literature about its pharmacological effects is available, it has not been used in Western medicine in the form of a pure chemical. No completed randomized controlled trials (RCTs) in human cancer populations have been identified for wogonin as a pure isolated compound.
The anti-inflammatory properties of wogonin are among its best-characterized activities in preclinical models. Studies across multiple cell types — including macrophages, lung epithelial cells, microglial cells, and vascular cells — consistently show inhibition of pro-inflammatory mediators. These flavonoids including wogonin have been studied for their potential beneficial effects on human health, including anti-allergenic, anti-inflammatory, cardiovascular and neuroprotective, hepatoprotective, immunomodulatory, skin barrier-enhancing, and anti-tumor activities.
Previous studies reported that wogonin has anti-inflammatory effects in several inflammation models; in a murine lung model, the in vivo protective effect of wogonin in the amelioration of lipopolysaccharide (LPS)-induced lung injury and inflammation was assessed.
Evidence assessment: Evidence is primarily from in vitro and animal studies. No human clinical trials specifically measuring wogonin's anti-inflammatory effects as an isolated compound have been published.
Wogonin has been found to be a potent neuroprotector from natural source. Studies on oxidative stress and bioavailability of wogonin have been discussed, along with its antineurodegenerative potential with special focus on Alzheimer's disease.
Anxiolytic activity (animal evidence): Oral administration of wogonin at doses of 7.5 to 30 mg/kg in mice elicited an anxiolytic response similar to that of diazepam in the elevated plus-maze, with a dose-dependent increase in open arm entries and time spent in open arms. This anxiolytic effect was blocked by co-administration of the BZD antagonist Ro15-1788. Wogonin-treated mice showed no signs of sedation in the holeboard test and did not display myorelaxant effects in the horizontal wire test, suggesting that wogonin exerts its anxiolytic effect through positive allosteric modulation of the GABAA receptor complex via the BZD site.
Anticonvulsant activity: Wogonin has also been found to possess anticonvulsant effects in animal studies. Other studies have reported that wogonin may exert anticonvulsant and neuroprotective effects through GABAergic mechanisms; however, while the evidence from laboratory and animal studies is promising, there is a lack of robust clinical trials in humans confirming these effects.
Evidence assessment: The strength of evidence is moderate at the preclinical level for wogonin's support of the GABA system due to the absence of human data. As of now, its use is not established in clinical practice, but ongoing research continues to explore its therapeutic potential for anxiety, epilepsy, and other disorders involving the GABA system.
Using an HBV-producing cell line (MS-G2) in vitro culture system, wogonin isolated from Scutellaria baicalensis was found to suppress HBV surface antigen production. Follow-up studies examined anti-hepatitis B virus activity both in vitro and in vivo in animal models (Guo et al., 2007, Antiviral Research). Activity against respiratory syncytial virus has also been described in the literature.
Evidence assessment: Antiviral evidence is entirely preclinical (cell-based and animal models). No human clinical trials have been conducted to assess wogonin's antiviral efficacy as a standalone compound.
Previous studies have reported that wogonin exerts hepatoprotective effects by modulating oxidative stress and inflammation in various pathological conditions, such as sepsis and liver fibrosis. Liver fibrosis is representative of chronic liver inflammation and is a characteristic of early cirrhosis, for which effective therapy has been lacking. Traditional Chinese Medicine has attracted increasing attention, and wogonin, as one major active constituent of Scutellariae radix, has been reported to play an important role in anti-inflammatory, anti-cancer, anti-viral, anti-angiogenesis, antioxidant, and neuroprotective effects.
Evidence assessment: Hepatoprotective evidence is preclinical. Human studies of wogonin's liver effects as an isolated compound are lacking.
Wogonin has been studied for potential anti-allergenic effects. Skin inflammation studies in animal models (Chi et al., 2003, Biochemical Pharmacology) have indicated in vivo regulation of inflammation-associated gene expression. These effects are studied primarily through inhibition of inflammatory mediators rather than direct anti-histamine action.
Evidence assessment: Anti-allergic evidence is confined to in vitro and animal studies.
Wogonin has been approved to be effective as an anti-inflammatory and antiviral inhibitor in cardiovascular diseases in preclinical research. A mouse pulmonary fibrosis model investigated the effects on cardiac function and myocardial fibrosis, with wogonin (50 mg/kg) administered intraperitoneally every 2 days for 2 weeks following bleomycin-induced pulmonary fibrosis, showing potential benefits on cardiac protection.
Evidence assessment: Cardiovascular evidence is preclinical and fragmented. No human cardiovascular RCTs have been published.
A recent study investigated wogonin's role as a key Scutellaria baicalensis (Huangqin) component in protecting against acute pancreatitis, with specific focus on TFEB-mediated autophagy activation. The study established wogonin as the pivotal bioactive driver behind Huangqin's therapeutic efficacy, orchestrating AMPK-TFEB-autophagy coordination to mitigate acute pancreatitis.
Evidence assessment: This evidence is from preclinical experimental models.
Pharmacokinetic studies have shown a rapid tissue distribution and prolonged plasma elimination phase of wogonin. A major limitation of wogonin as an orally administered agent is its very low bioavailability.
In rats: After intragastric dosing at 100 mg/kg, plasma levels of wogonin peaked at 28 minutes with a Cmax value of 300 ng/mL and a very low oral bioavailability of 1.10%. Following intravenous single dose (20 mg/kg), wogonin was detected in all examined tissues (including testis), with the highest levels found in the kidney and liver.
After intravenous dosing of wogonin at different levels (10, 20, and 40 mg/kg), the elimination half-life was approximately 14 minutes, and the AUC0-∞ increased in a dose-disproportional manner, indicating a non-linear pharmacokinetic profile. Approximately 21% of the administered dose was excreted as unchanged drug (mainly via the non-biliary fecal route at 16.33%). Plasma protein binding evaluated by equilibrium dialysis at three concentrations indicated a very high protein binding degree (over 90%), substantially reducing the free fraction of the compound.
In beagles: The absolute bioavailability of native wogonin and wogonin arginine solution in beagles were 0.59±0.35% and 3.65±2.60%, respectively. Further research showed that the low bioavailability of wogonin might be associated with low solubility and rapid combination with glucuronic acid in vivo.
The oral bioavailability of wogonin is low, and bioavailability enhancement through nanotechnology tools is being explored to allow better utilization of its potential benefits on human health. Formulation approaches, including solid dispersions and arginine solutions, have been shown to significantly increase the bioavailability of wogonin.
Wogonin is consumed primarily as part of whole-plant preparations of Scutellaria baicalensis (root decoctions, tinctures, standardized extracts, capsules, or tablets). As an isolated compound, it has been used only in preclinical research settings; no standardized human dosage has been established through clinical trials.
The safety record of wogonin is notable, and a voluminous literature about its pharmacological effects is available. Despite all therapeutic potential, all new drugs require in-depth study, even natural ones, since they could present side effects such as effects of high dosage and long-term use.
A study investigating the effect of wogonin on human hepatic cytochrome P450s (CYP450s) in vitro used isoform-specific substrate probes of CYP1A2, 2C9, 2C19, 2D6, 2E1, and 3A4 incubated in human liver microsomes. Wogonin was found to be a potent, competitive inhibitor of CYP1A2 (Ki = 0.24 μM) and a weak inhibitor of CYP2C19 (IC₅₀ = 101.10 μM), but was not able to inhibit CYP2C9, CYP2D6, CYP2E1, and CYP3A4 (IC₅₀ >200 μM). These findings suggested that it is necessary to study the potential pharmacokinetic drug interactions in vivo.
In vitro data indicate that wogonin inhibits CYP1A2 and CYP2C19 and may affect intracellular concentrations of drugs metabolized by these enzymes; however, the clinical relevance has yet to be determined.
In vitro, baicalein, baicalin, and wogonin have been found to inhibit the uptake of substrates mediated by essential solute carrier transporters — membrane proteins responsible for the cellular influx of various drugs. The clinical relevance of this finding has yet to be determined.
Studies indicate that Scutellaria baicalensis comprises many bioactive compounds, such as baicalein, baicalin, and wogonin, which are associated with pharmacokinetic and pharmacodynamic interactions with a wide range of drugs. S. baicalensis and its bioactives including baicalein, baicalin, and wogonin exhibited synergistic interactions with many pharmaceutical drugs to enhance their efficacy, reduce toxicity, or overcome drug resistance; on the other hand, they also affected the pharmacokinetic profile of many drugs in absorption, distribution, metabolism, and elimination via the regulatory actions of efflux pumps and cytochrome P450 enzymes.
Lab studies suggest Chinese skullcap has similar effects to warfarin or other blood thinners and may therefore increase bruising and bleeding risks, though clinical relevance has yet to be determined. In healthy volunteers, Chinese skullcap was reported to decrease blood levels of drugs used to lower cholesterol (statins).
Case reports of acute liver injury have been documented in patients with arthritis following consumption of a formula containing baicalin derived from S. baicalensis or Chinese skullcap. This signal is associated with the whole-plant preparation rather than isolated wogonin, and distinguishing causative compounds in complex preparations is methodologically difficult.
Equilibrium dialysis evaluation of plasma protein binding at three concentrations (0.1, 0.5, and 2 μg/mL) indicated a very high protein binding degree (over 90%) for wogonin, substantially reducing the free fraction of the compound. This high protein binding has implications for potential displacement interactions with other highly protein-bound drugs, though this has not been formally evaluated in human studies.
The search for flavonoids with novel therapeutic effects has been intense. Wogonin, as a naturally existing monoflavonoid, has been shown to have therapeutic potential in vitro and in vivo. A significant ingredient in S. baicalensis that has been the subject of the most research, numerous preclinical investigations have revealed that wogonin suppresses tumor growth by cell cycle arrest, stimulating cell death, and preventing metastasis.
Despite this broad preclinical profile, a fundamental translational gap exists. To the best of knowledge in the published review literature, no clinical trials have been conducted on wogonin as an isolated molecule. The scientific evidence aims to encourage the development of new clinical evidence that studies the therapeutic effect of wogonin, enriched extracts, or enriched herbal treatments that adequately report phytocomposition.
The use of contemporary nanotechnological techniques to address the low bioavailability problems typical of natural chemicals is being explored, with the goal of eventually using wogonin in therapeutic settings. The development of formulations such as solid dispersions, nanoparticle carriers, and arginine salts is an active area of pharmaceutical research aimed at making wogonin a viable clinical agent.
Additional research on the chemistry and toxicological profile of wogonin is needed to confirm its safety issues.
Health conditions that Wogonin may help support.
Wogonin is a bioactive flavone from Scutellaria baicalensis with documented anti-inflammatory and antiviral properties relevant to post-viral recovery. It inhibits NF-κB signaling, reduces NLRP3 inflammasome activation, and has shown activity against SARS-CoV-2 in molecular docking and in vitro studies.
Wogonin is a bioactive flavone from Baikal skullcap (Scutellaria baicalensis) with antiviral and anti-inflammatory properties. It inhibits viral replication including influenza, HIV, and HBV, and reduces viral-induced cytokine storm via NF-κB inhibition. Traditional use in TCM for febrile viral conditions is longstanding.
Body systems that Wogonin may help support.
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