Physiological effects following administration of Citrus aurantium for 28 days in rats
- Division of Personalized Nutrition and Medicine, U.S. FDA/NCTR, 3900 NCTR Rd., Jefferson, AR 72079 (United States)
- Toxicological Pathology Associates, 3900 NCTR Rd., Jefferson, AR 72079 (United States)
- Office of New Drugs, U.S. FDA/Center for Drug Evaluation and Research, 10903 New Hampshire Ave., Silver Spring, MD 20903 (United States)
- Office of Nutrition, Labeling and Dietary Supplements, U.S. FDA/Center for Food Safety and Nutrition, HFS-810, College Park, MD 20740 (United States)
Background: Since ephedra-containing dietary supplements were banned from the US market, manufacturers changed their formulations by eliminating ephedra and replacing with other botanicals, including Citrus aurantium, or bitter orange. Bitter orange contains, among other compounds, synephrine, a chemical that is chemically similar to ephedrine. Since ephedrine may have cardiovascular effects, the goal of this study was to investigate the cardiovascular effects of various doses of bitter orange extract and pure synephrine in rats. Method: Female Sprague–Dawley rats were dosed daily by gavage for 28 days with synephrine from two different extracts. One extract contained 6% synephrine, and the other extract contained 95% synephrine. Doses were 10 or 50 mg synephrine/kg body weight from each extract. Additionally, caffeine was added to these doses, since many dietary supplements also contain caffeine. Telemetry was utilized to monitor heart rate, blood pressure, body temperature and QT interval in all rats. Results and conclusion: Synephrine, either as the bitter orange extract or as pure synephrine, increased heart rate and blood pressure. Animals treated with 95% synephrine showed minimal effects on heart rate and blood pressure; more significant effects were observed with the bitter orange extract suggesting that other components in the botanical can alter these physiological parameters. The increases in heart rate and blood pressure were more pronounced when caffeine was added. None of the treatments affected uncorrected QT interval in the absence of caffeine.
- OSTI ID:
- 22215333
- Journal Information:
- Toxicology and Applied Pharmacology, Journal Name: Toxicology and Applied Pharmacology Journal Issue: 3 Vol. 261; ISSN TXAPA9; ISSN 0041-008X
- Country of Publication:
- United States
- Language:
- English
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