Drynaria Fortunei Extract
Also known as: Drynaria fortunei, Drynaria rhizome, Gusuibu, Drynaria fortunei extract
Overview
Drynaria fortunei extract is derived from the rhizome of the fern Drynaria fortunei, a plant traditionally used in East Asian medicine to strengthen bones and treat bone-related conditions like osteoporosis. This herbal extract is rich in flavonoids, particularly naringin, which are believed to contribute to its bone-protective and metabolic regulatory effects. It is primarily utilized as a supplement for improving bone mineral density (BMD), aiding in bone fracture healing, and potentially for metabolic regulation related to obesity. Research on Drynaria fortunei extract is moderate, with several randomized controlled trials (RCTs) and systematic reviews, predominantly from Chinese clinical studies. While evidence suggests benefits for bone health, some studies have methodological limitations, and independent replication is ongoing. The extract is typically standardized for its total flavonoid content.
Benefits
The primary benefit of Drynaria fortunei extract is its positive impact on bone health. Meta-analyses indicate that it significantly improves bone mineral density (BMD) in osteoporotic patients, showing statistically significant increases compared to conventional treatments or placebo, with a weighted mean difference in BMD improvement of approximately 0.14 g/cm² (p<0.00001). It also appears to reduce fracture recurrence and enhance the therapeutic effect in osteoporotic fractures, with an odds ratio for therapeutic effect around 0.25 (p=0.0002). These benefits are most relevant for postmenopausal women and elderly patients with osteoporosis. Secondary benefits, observed in animal models, include anti-obesity effects, such as reduced body weight and lipid accumulation, through the modulation of lipid metabolism-related transcription factors and activation of AMPK-α. Clinical significance for bone health is supported, but interpretation should be cautious due to varying study quality. Benefits typically manifest over several weeks to months of consistent use.
How it works
Drynaria fortunei extract exerts its effects primarily through its flavonoid components, such as naringin. These compounds are believed to inhibit the mevalonate pathway, a mechanism similar to that of bisphosphonates, which leads to a reduction in bone resorption. Additionally, the extract activates AMP-activated protein kinase (AMPK), which plays a crucial role in improving lipid metabolism and may contribute to bone anabolic effects. It also downregulates lipogenesis transcription factors like SREBP-1 and PPAR-γ, thereby reducing fat accumulation, which can indirectly benefit bone metabolism. While the specific pharmacokinetics of Drynaria flavonoids require further study, their general bioavailability is considered moderate.
Side effects
Drynaria fortunei extract is generally well-tolerated in clinical trials, with mild adverse effects being the most common. The most frequently reported side effects (occurring in over 5% of users) are gastrointestinal symptoms, including nausea and mild digestive discomfort. Uncommon side effects (1-5%) have not been clearly reported in the available literature, and rare side effects (less than 1%) have also not been documented. Potential drug interactions exist, particularly with other medications affecting bone metabolism, such as bisphosphonates, due to overlapping biochemical pathways; caution is advised when combining these treatments. Contraindications are not well-defined, but caution is recommended for individuals with severe liver or kidney disease due to limited safety data in these populations. Safety in pregnant or lactating women has not been established, and data primarily comes from adult patients with osteoporosis.
Dosage
The minimum effective dose for Drynaria fortunei extract is not standardized, but clinical trials have typically used total flavonoids from Rhizoma Drynariae (TFRD) in doses ranging from approximately 300-600 mg/day of flavonoids. This range is also considered the optimal dosage based on current clinical studies, although further validation is needed. The maximum safe dose has not been clearly established, but no severe adverse events have been reported at the studied dosages. The extract is administered orally, typically on a daily basis, with study durations commonly ranging from 3 to 6 months. It is important to use extracts standardized for total flavonoid content, especially naringin. While specific cofactors for absorption have not been identified, co-administration with food may influence flavonoid absorption.
FAQs
Is Drynaria fortunei extract effective for osteoporosis?
Evidence suggests moderate improvement in bone mineral density (BMD) and fracture healing, but more high-quality randomized controlled trials are needed to confirm its full efficacy.
Is Drynaria fortunei extract safe to use?
It is generally considered safe with mild gastrointestinal side effects, such as nausea and digestive discomfort, being the most commonly reported.
Can Drynaria fortunei extract be combined with standard osteoporosis drugs?
Some evidence suggests potential additive effects with bisphosphonates, but interactions are not fully understood, and caution is advised.
How long does it take to see effects from Drynaria fortunei extract?
Clinical improvements typically become observable after several months of consistent daily use, as seen in research studies.
Does Drynaria fortunei extract help with weight loss?
Animal studies indicate potential anti-obesity effects, but human data are currently lacking, so it is not recommended for weight loss based on current evidence.
Research Sources
- https://pmc.ncbi.nlm.nih.gov/articles/PMC10784730/ – This animal study demonstrated that Drynaria rhizome extract reduced body weight and lipid accumulation in high-fat diet-induced obese mice. The mechanism involved AMPK activation and downregulation of lipogenesis transcription factors, suggesting potential metabolic benefits relevant to bone health.
- https://pmc.ncbi.nlm.nih.gov/articles/PMC5491704/ – This systematic review and meta-analysis of 6 RCTs found that total flavonoids from Rhizoma Drynariae significantly improved BMD and reduced fracture recurrence in osteoporotic patients compared to conventional treatments. Mild gastrointestinal adverse events were reported, and methodological limitations in included RCTs were noted.
- https://www.frontiersin.org/journals/pharmacology/articles/10.3389/fphar.2024.1413515/full – This systematic review highlighted that naringin, a key flavonoid in Drynaria fortunei, inhibits the mevalonate pathway, similar to bisphosphonates, contributing to improved bone mineral density. It also noted the complexity of attributing effects in multi-compound herbal medicines to a single pathway.
