Oroxylin A

Oroxylin A is a flavonoid compound found in Scutellaria baicalensis that modulates neuroinflammation through GABA-A receptor activation and NF-κB pathway inhibition. This bioactive flavone demonstrates neuroprotective properties by reducing oxidative stress and supporting cognitive function in preclinical studies.

Origin & History

Oroxylin A is an O-methylated flavone (5,7-dihydroxy-6-methoxyflavone) isolated primarily from the root bark of Oroxylum indicum and Scutellaria baicalensis. It appears as yellow plates with a melting point of 231-232°C and is extracted from plant materials through standard phytochemical isolation methods confirmed by NMR, IR, UV, and MS analysis.

Historical & Cultural Context

While Oroxylin A occurs in traditional medicinal plants like Scutellaria baicalensis and Oroxylum indicum, specific historical applications or traditional medicine uses for the isolated compound are not documented in the available sources. The parent plants have medicinal history, but isolated compound usage lacks traditional context.

Health Benefits

• May support cognitive function through modulation of neurodegenerative pathways (mechanism research only)
• Potential anti-inflammatory effects via cyclooxygenase enzyme inhibition (in vitro evidence)
• May influence cell survival and apoptosis through NF-κB pathway modulation (preliminary research)
• Possible neuroprotective properties based on its flavonoid structure (theoretical based on compound class)
• Limited evidence prevents specific health benefit claims pending human clinical trials

How It Works

Oroxylin A functions as a positive allosteric modulator of GABA-A receptors, particularly the α2β2γ2 subtype, enhancing inhibitory neurotransmission in the brain. The compound suppresses neuroinflammation by inhibiting NF-κB translocation and reducing pro-inflammatory cytokine production including TNF-α and IL-1β. Additionally, oroxylin A modulates apoptotic pathways by upregulating Bcl-2 expression while downregulating Bax and cleaved caspase-3 proteins.

Scientific Research

No human clinical trials, RCTs, or meta-analyses for Oroxylin A were identified in the available research. Current evidence is limited to in vitro mechanism studies showing enzyme inhibition and pathway modulation, with general pharmacological interest noted for cognitive and neurodegenerative applications.

Clinical Summary

Current evidence for oroxylin A comes primarily from in vitro cell culture studies and animal models, with limited human clinical data available. Preclinical studies in mice have shown cognitive improvements at doses of 5-20 mg/kg, with enhanced memory performance in Morris water maze tests. Cell culture experiments demonstrate neuroprotective effects at concentrations of 1-50 μM against oxidative stress-induced damage. The evidence base remains preliminary, requiring randomized controlled trials to establish clinical efficacy and optimal dosing in humans.

Nutritional Profile

Oroxylin A (5,7-dihydroxy-6-methoxyflavone) is a pure bioactive flavonoid compound, not a whole food ingredient, and therefore carries no meaningful macronutrient, micronutrient, fiber, or protein content in the conventional nutritional sense. As a compound, it is characterized entirely by its bioactive chemical identity: Molecular formula C16H12O5, molecular weight 284.26 g/mol. It belongs to the flavone subclass of polyphenols, featuring a characteristic 4H-chromen-4-one backbone with hydroxyl groups at positions 5 and 7 and a methoxy group at position 6. Naturally sourced primarily from the root bark of Oroxylum indicum (Indian trumpet tree) and from Scutellaria baicalensis (Chinese skullcap), where it occurs at concentrations typically ranging from 0.1–2.5% dry weight depending on plant part and extraction method. Bioavailability is notably limited due to poor aqueous solubility (log P approximately 2.8, indicating moderate lipophilicity), with oral bioavailability in animal models estimated below 20% without formulation enhancement. It undergoes phase II hepatic metabolism (glucuronidation and sulfation), and nanoparticle or lipid-based delivery systems have been shown in research to improve absorption by 3–5 fold. No caloric value, vitamins, or minerals are contributed by this compound in isolation.

Preparation & Dosage

No clinically studied dosage ranges are available for Oroxylin A. Forms, standardization methods, and therapeutic doses have not been established through human research. Consult a healthcare provider before starting any new supplement.

Synergy & Pairings

Other flavonoids, baicalin, Scutellaria baicalensis extract, cognitive support compounds

Safety & Interactions

Safety data for oroxylin A in humans is limited due to the lack of comprehensive clinical trials. The compound may enhance the effects of GABAergic medications including benzodiazepines, barbiturates, and sleep aids due to its GABA-A receptor activity. Potential interactions with anticoagulant medications are possible given the flavonoid structure. Pregnant and breastfeeding women should avoid oroxylin A supplementation due to insufficient safety data during these periods.