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Does 5-hydroxytryptophan cause acute and chronic toxic perturbations in rats?
Harry G Preuss1, Bobby Echard, Nadeem Talpur
1Department of Physiology and Biophysics, Georgetown University Medical Center, Washington, DC.
Toxicology Mechanisms and Methods
|December 22, 2009
Summary
This study found that 5-hydroxytryptophan (5-HTP) did not cause eosinophilia-myalgia syndrome (EMS) in rats, even at high doses. Researchers observed no EMS-related changes, suggesting 5-HTP is safe and does not induce this condition.
Area of Science:
- Toxicology
- Pharmacology
- Immunology
Background:
- An eosinophilia-myalgia syndrome (EMS) epidemic in 1989 was linked to contaminated L-tryptophan (LT).
- Following the LT epidemic, 5-hydroxytryptophan (5-HTP) replaced LT, but a 1994 case of EMS raised concerns about potential 5-HTP contamination ('Peak X').
Purpose of the Study:
- To investigate whether 5-hydroxytryptophan (5-HTP) can induce eosinophilia-myalgia syndrome (EMS).
Main Methods:
- 120 male Sprague-Dawley rats were divided into three groups: control (water), low-dose 5-HTP (87.5 mg/dL), and high-dose 5-HTP (875 mg/dL).
- Rats were monitored for 1 year, with assessments of body weight, systolic blood pressure, hematology, liver and renal function, and histology of multiple organs.
Main Results:
- No significant differences in body weight or hematological values (including eosinophil count) were observed between groups.
- Systolic blood pressure was significantly lower in both 5-HTP groups compared to controls throughout the study.
- Histological examination revealed no treatment-related changes indicative of EMS, such as eosinophilic infiltration or inflammation.
Conclusions:
- High-dose 5-hydroxytryptophan (5-HTP) administration did not induce eosinophilia-myalgia syndrome (EMS) in rats.
- The study suggests that 5-HTP is not a causative agent for EMS, despite concerns raised by previous cases.
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