# Heptamethoxyflavone

**Canonical URL:** https://ingredients.hermeticasuperfoods.com/ingredients/heptamethoxyflavone
**Data Source:** Hermetica Superfoods Ingredient Encyclopedia
**Updated:** 2026-04-04
**Evidence Score:** 2 / 10
**Category:** Compound
**Also Known As:** 5,6,7,8,3',4',5'-heptamethoxyflavone, HMF, Polymethoxyflavone HMF, Heptamethoxy flavone, 7-methoxyflavone derivative

## Overview

Heptamethoxyflavone is a polymethoxylated flavone found primarily in citrus peel that exhibits multidrug resistance modulation and kinase inhibition activity. Its primary mechanisms involve inhibiting ATP-binding cassette efflux transporters such as ABCG2 and P-glycoprotein 1, potentially enhancing intracellular drug accumulation in cancer cell models.

## Health Benefits

• May modulate multidrug resistance via efflux pump inhibition, as shown by in vitro studies on ABCG2 and P-glycoprotein 1, though human clinical trials are lacking.[1] • Potentially influences gene expression and kinase activity by targeting proteins like dual specificity protein phosphatase 3 and Kruppel-like factor 5, although these are predicted targets not validated experimentally.[1] • Shows inhibition of DNA topoisomerase II alpha, suggesting a role in transcriptional regulation, albeit without direct human evidence.[1] • Predicted to impact [oxidative stress](/ingredients/condition/antioxidant) responses via NRF2, based on computational models, but not confirmed in vivo.[1] • Could affect drug [metabolism](/ingredients/condition/weight-management) through pregnane X receptor interaction, yet this remains a theoretical benefit without clinical validation.[1]

## Mechanism of Action

Heptamethoxyflavone inhibits ATP-binding cassette transporters ABCG2 and P-glycoprotein 1, reducing efflux of substrates from cells and potentially reversing multidrug resistance phenotypes in vitro. It also targets dual specificity protein phosphatase 3 (DUSP3), modulating downstream MAPK and ERK signaling cascades that regulate cell proliferation and survival. Additionally, its seven methoxy substituents on the flavone backbone enhance lipophilicity, facilitating membrane permeability and interaction with intracellular kinase targets.

## Clinical Summary

Research on heptamethoxyflavone is predominantly limited to in vitro cell-based studies and computational docking analyses, with no published randomized controlled human clinical trials as of 2024. In vitro studies using cancer cell lines have demonstrated inhibition of ABCG2-mediated drug efflux at micromolar concentrations, suggesting theoretical utility in overcoming chemotherapy resistance. Animal pharmacokinetic data on structurally related polymethoxylated flavones indicate moderate oral bioavailability and hepatic [metabolism](/ingredients/condition/weight-management), though species-specific differences complicate direct human extrapolation. The overall evidence base is preliminary, and efficacy and safety conclusions for human supplementation cannot be drawn from current data.

## Nutritional Profile

Heptamethoxyflavone (5,6,7,8,3',4',5'-heptamethoxyflavone; C₂₂H₂₄O₉; MW ~436.4 g/mol) is a polymethoxylated flavone, not a macronutrient source. It provides negligible calories, protein, fat, fiber, or carbohydrates at bioactive doses. Key details: • **Bioactive classification:** Polymethoxylated flavone (PMF), structurally related to nobiletin (hexamethoxyflavone) and tangeretin (pentamethoxyflavone). Distinguished by having seven methoxy (–OCH₃) substituents on the flavone backbone at positions 5, 6, 7, 8, 3', 4', and 5'. • **Natural occurrence & approximate concentrations:** Found predominantly in Citrus species peels, particularly in Kaempferia parviflora (black ginger) rhizome and certain citrus peel extracts. Concentrations in citrus peel oils/extracts are typically low, estimated at ~0.01–0.5% of dried peel weight depending on cultivar, extraction method, and tissue. In Kaempferia parviflora extracts, PMFs including heptamethoxyflavone may constitute roughly 1–5% of standardized ethanolic extracts. • **Vitamins & minerals:** None intrinsic; heptamethoxyflavone is a single phytochemical, not a whole-food matrix. • **Bioavailability notes:** Oral bioavailability is expected to be low-to-moderate, consistent with other polymethoxylated flavones. The seven methoxy groups increase lipophilicity (estimated logP ~2.5–3.5) compared to hydroxylated flavonoids, which generally improves membrane permeability and metabolic stability relative to polyhydroxylated analogs. However, first-pass hepatic [metabolism](/ingredients/condition/weight-management) (CYP450-mediated O-demethylation) and intestinal efflux (P-glycoprotein, ABCG2 substrates) likely limit systemic exposure. Co-administration with lipids or formulation in nanoemulsions/liposomes may enhance absorption. Plasma half-life data in humans are not well established; rodent studies on related PMFs suggest t½ of ~1–4 hours. Metabolites (demethylated and glucuronidated forms) may retain partial biological activity. • **Typical study doses (preclinical context):** In vitro studies commonly use 1–100 µM; in vivo rodent studies typically administer 10–50 mg/kg body weight orally. No established human dosing exists. • **No significant macro- or micronutrient contribution** at pharmacologically relevant doses (estimated human-equivalent doses would be in the range of ~50–500 mg/day based on allometric scaling from rodent data, providing essentially zero nutritional energy).

## Dosage & Preparation

There are no clinically studied dosage ranges or forms available for heptamethoxyflavone, as human trials are absent in the current research. Consult a healthcare provider before starting any new supplement.

## Safety & Drug Interactions

No human clinical safety data specific to heptamethoxyflavone supplementation are currently available, making formal risk characterization difficult. Because it inhibits P-glycoprotein 1 and ABCG2 transporters, concurrent use with P-gp or BCRP substrate drugs such as digoxin, rosuvastatin, or certain chemotherapeutics could theoretically increase plasma drug levels and toxicity risk. Polymethoxylated flavones as a class are metabolized via cytochrome P450 enzymes including CYP1A2 and CYP3A4, suggesting possible interactions with medications sharing these metabolic pathways. Use during pregnancy or lactation is not recommended due to the complete absence of safety data in these populations.

## Scientific Research

No human clinical trials or meta-analyses have been conducted on heptamethoxyflavone. Current evidence is limited to in vitro assays with IC50 values for ABCG2 and P-glycoprotein 1.[1] No PMIDs available for human studies.

## Historical & Cultural Context

There are no documented historical or traditional medicinal uses for heptamethoxyflavone in the research provided. Its use is primarily based on its presence in certain citrus plants.

## Synergistic Combinations

Naringenin, Quercetin, Resveratrol, Apigenin, Hesperidin

## Frequently Asked Questions

### What is heptamethoxyflavone found in?

Heptamethoxyflavone is a polymethoxylated flavone found primarily in the peel and essential oils of citrus fruits, particularly species such as Citrus depressa and other members of the Rutaceae family. It co-occurs with structurally related compounds like nobiletin and tangeretin, which are more extensively studied members of the same polymethoxylated flavone subclass.

### Can heptamethoxyflavone help with drug resistance in cancer?

In vitro studies suggest heptamethoxyflavone can inhibit ABCG2 and P-glycoprotein 1 efflux pumps, which are mechanisms cancer cells use to expel chemotherapy drugs and develop resistance. These findings come exclusively from cell line experiments, and no human trials have tested whether this translates to clinical benefit or safe co-administration with chemotherapy agents.

### What enzymes does heptamethoxyflavone inhibit?

Heptamethoxyflavone has been identified computationally and in vitro as an inhibitor of dual specificity protein phosphatase 3 (DUSP3), an enzyme that dephosphorylates and inactivates ERK1/2 and JNK MAP kinases. By inhibiting DUSP3, heptamethoxyflavone may sustain phosphorylation states of these kinases, with downstream effects on cell cycle regulation and apoptosis signaling.

### Is there a recommended dosage for heptamethoxyflavone supplements?

No clinically established or evidence-based dosage recommendation exists for heptamethoxyflavone in humans, as it has not been studied in human clinical trials. Dosages used in in vitro research typically range from 1 to 50 micromolar concentrations in cell media, which do not directly translate to oral human dosing without pharmacokinetic bridging studies.

### Does heptamethoxyflavone interact with any medications?

Heptamethoxyflavone may interact with medications that are substrates of P-glycoprotein 1 or ABCG2 transporters, including digoxin, rosuvastatin, sulfasalazine, and certain tyrosine kinase inhibitors, by inhibiting their efflux and increasing systemic exposure. It may also affect drugs metabolized by CYP1A2 and CYP3A4 enzymes based on metabolic patterns observed with related polymethoxylated flavones, though direct interaction studies in humans are absent.

### What does clinical research show about heptamethoxyflavone's effectiveness in humans?

Most evidence for heptamethoxyflavone comes from in vitro and animal studies demonstrating potential effects on drug resistance pathways and enzyme inhibition. Human clinical trials are currently lacking, meaning its real-world efficacy and safety in people remain unestablished. Any supplement claims should be viewed as preliminary until peer-reviewed human studies are published.

### How does heptamethoxyflavone compare to other flavone derivatives for multidrug resistance?

Heptamethoxyflavone is studied for ABCG2 and P-glycoprotein 1 inhibition, similar to other polymethoxylated flavones, but direct comparative studies are limited. Its potency and selectivity relative to compounds like tangeretin or nobiletin have not been systematically evaluated in clinical settings. The methylation pattern may influence its bioavailability and target specificity compared to less-methylated flavones.

### Who should consider heptamethoxyflavone supplementation based on current research?

Currently, heptamethoxyflavone is primarily of interest to researchers and individuals exploring experimental approaches to chemotherapy resistance, as human safety and efficacy data do not support general consumer recommendations. People with cancer undergoing conventional treatment should consult oncologists before use, as potential drug interactions remain poorly characterized. Until clinical trials establish clear benefits and safety profiles, supplementation outside research contexts is not evidence-based.

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*Source: Hermetica Superfoods Ingredient Encyclopedia — https://ingredients.hermeticasuperfoods.com*
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