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Radix astragali and orthostatic response: a double-masked crossover study
Yunfang Gao1, Nandu Goswami, Erik Grasser
1Department of Biology, College of Life Sciences, Northwest University, Xi'an, China.
Aviation, Space, and Environmental Medicine
|March 4, 2008
Summary
Radix Astragali (RA), a traditional Chinese herb, does not affect cardiovascular stability or orthostatic tolerance in healthy men. This suggests RA is safe for human studies investigating its potential to combat muscle atrophy.
Area of Science:
- Cardiovascular Physiology
- Integrative Physiology
- Pharmacology
Background:
- Radix Astragali (RA) shows promise in animal models for mitigating muscle atrophy under simulated weightlessness.
- Potential cardiovascular side effects of RA have not been evaluated in humans.
- Assessing orthostatic stability is crucial for understanding RA's safety profile.
Purpose of the Study:
- To investigate the effects of Radix Astragali (RA) on orthostatic stability in healthy human subjects.
- To determine if RA influences cardiovascular responses to orthostatic stress.
- To assess the safety of RA as a potential countermeasure for muscle atrophy.
Main Methods:
- A double-blinded, randomized crossover study involving 10 healthy men.
- Subjects received Radix Astragali (RA) or placebo (PL) for 14 days, with a 14-day washout period.
- Graded orthostatic stress (GOS), combining head-up tilt (HUT) and lower body negative pressure (LBNP), was used to assess presyncopal endpoints.
Main Results:
- No significant differences were observed between RA and placebo groups in mean arterial blood pressure, pulse pressure, heart rate, or stroke volume index.
- Radix Astragali (RA) did not alter standing time or tolerance to graded orthostatic stress compared to placebo.
- Cardiovascular variables remained stable, indicating no adverse effects on orthostatic capacity.
Conclusions:
- Radix Astragali (RA) does not appear to affect resting cardiovascular function or orthostatic capacity in humans at the tested dosage.
- The findings suggest that cardiovascular side effects are unlikely to compromise human studies on RA's potential for muscle atrophy countermeasures.
- RA can be considered a potentially safe option for further research into its therapeutic applications.
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