Drynaria Fortunei Rhizome Extract
Also known as: Rhizoma Drynariae, Gu Sui Bu, Drynaria fortunei (Kunze) J. Sm., Drynaria fortunei rhizome extract
Overview
Drynaria fortunei rhizome extract is derived from the dried rhizome of the fern Drynaria fortunei, a plant traditionally used in East Asia for bone-related ailments such as osteoporosis and fractures. It is rich in total flavonoids, which are considered the primary bioactive compounds responsible for its therapeutic effects. The extract is primarily valued for its antiosteoporotic, bone-strengthening, and anti-inflammatory properties. Research, including in vitro, animal models, and clinical trials, supports its application in bone health, particularly for improving bone mineral density and aiding fracture healing. While promising, some clinical studies have methodological limitations, indicating a need for further high-quality research.
Benefits
The primary benefit of Drynaria fortunei rhizome extract is its significant improvement in bone mineral density (BMD) in osteoporotic patients, with meta-analyses showing statistically significant increases (e.g., WMD = 3.68, 95% CI: 0.01 to 0.04, p=0.0002). It also enhances therapeutic effects in osteoporotic fracture treatment, demonstrating better outcomes compared to conventional treatments alone (OR=0.25; 95% CI: 0.12 to 0.51; p=0.0002). The extract promotes osteoblast proliferation and differentiation, leading to improved bone formation and mineralization. Secondary benefits include antioxidant activity, which contributes to overall bone health, and potential anti-obesity effects through modulation of lipid metabolism and AMPK activation, indirectly supporting bone metabolism in obese models. Postmenopausal women with osteoporosis particularly benefit from improved bone density and reduced fracture risk. The observed improvements in BMD and fracture healing are statistically significant and clinically relevant, with benefits typically observed within weeks to several months of consistent use.
How it works
Drynaria fortunei rhizome extract primarily exerts its effects through its total flavonoid content. These flavonoids upregulate osteoprotegerin (OPG) and downregulate receptor activator of nuclear factor kappa-Β ligand (RANKL), thereby increasing the OPG/RANKL ratio. This mechanism inhibits osteoclast-mediated bone resorption and promotes osteogenesis. The extract also enhances osteoblast activity and differentiation, leading to increased bone formation markers. Furthermore, it exhibits antioxidant properties, reducing oxidative stress in bone tissue. In some contexts, it modulates lipid metabolism and activates AMP-activated protein kinase (AMPK), which may contribute to improved bone metabolism, especially in obesity. The bioavailability and efficacy are linked to the flavonoid content, with ethanol extracts generally showing higher efficacy due to better flavonoid extraction.
Side effects
Drynaria fortunei extract is generally considered safe with a favorable safety profile. The most common side effects reported are mild gastrointestinal symptoms, such as nausea or discomfort, occurring in over 5% of users in some clinical trials. Uncommon side effects (1-5%) have not been significantly reported in high-quality studies, and rare side effects (less than 1%) are not documented in the reviewed literature. There are no well-documented drug interactions, but caution is advised when combining it with other bone-active agents or anticoagulants due to its flavonoid content. Contraindications are not well-defined; however, due to a lack of sufficient data, caution is recommended during pregnancy and lactation. While extensively studied in postmenopausal women, its effects in other populations are less documented.
Dosage
Clinical studies typically use total flavonoids from Rhizoma Drynariae (TFRD) in doses standardized to their flavonoid content. Common daily dosages range from approximately 500 mg to 1 g of the standardized extract. The optimal dosage can vary depending on the specific formulation and extract concentration; for instance, ethanol extracts may require lower doses due to their higher flavonoid content and enhanced absorption. The extract is typically administered orally, often once daily, and can be taken with or without food. While no specific cofactors are required for absorption, adequate intake of calcium and vitamin D is recommended to synergistically support bone health. Flavonoids generally have moderate bioavailability.
FAQs
Is Drynaria fortunei extract effective for osteoporosis?
Yes, clinical evidence supports its efficacy in improving bone mineral density and reducing fracture risk, particularly in postmenopausal osteoporosis.
Is it safe for long-term use?
Generally safe with mild gastrointestinal side effects; long-term safety data are limited, but no serious adverse effects have been reported in available studies.
How quickly can benefits be seen?
Improvements in bone density and fracture healing are typically observed within weeks to months of consistent use.
Can it be combined with conventional osteoporosis treatments?
Some studies suggest additive benefits when combined with conventional therapies, but consultation with a healthcare provider is advised.
Research Sources
- https://www.ptfarm.pl/pub/File/Acta_Poloniae/2015/6/1073%20poprawka.pdf – This preclinical study investigated the effects of Drynaria fortunei ethanol and water extracts on osteoblast proliferation and bone mineralization in vitro and in ovariectomized rats. It found that the ethanol extract significantly enhanced osteoblast activity and bone formation, demonstrating better antioxidant activity than the water extract. The research provides strong mechanistic and efficacy evidence for the extract's bone-strengthening properties in animal models.
- https://pmc.ncbi.nlm.nih.gov/articles/PMC10784730/ – This controlled animal study explored the effects of Drynaria fortunei rhizome extract (DRE) in high-fat diet-induced obese mice. It revealed that DRE reduced body weight, modulated lipid metabolism, and activated AMP-activated protein kinase (AMPK). This suggests a potential role for DRE in benefiting bone metabolism within the context of obesity, offering preliminary but promising insights into its metabolic-bone interactions.
- https://pmc.ncbi.nlm.nih.gov/articles/PMC5491704/ – This systematic review and meta-analysis synthesized data from six randomized controlled trials involving 846 patients with osteoporotic fractures. It concluded that total flavonoids from Rhizoma Drynariae (TFRD) significantly improved bone mineral density and enhanced therapeutic effects in these patients, with only mild adverse drug reactions reported. Despite some methodological flaws in the included RCTs, the study provides moderate-quality evidence supporting the efficacy of TFRD for osteoporosis.
- https://www.frontiersin.org/journals/pharmacology/articles/10.3389/fphar.2022.881057/full – This experimental study, conducted on broiler chickens, investigated the mechanism by which total flavonoids from Rhizoma Drynariae (TFRD) promote bone growth. The findings indicated that TFRD modulated the osteoprotegerin (OPG)/receptor activator of nuclear factor kappa-Β ligand (RANKL) ratio, thereby reducing bone disorders. This research supports the understanding of TFRD's mechanism of action in bone remodeling, although its direct relevance to human physiology requires further investigation.