Biochemical evidence of vitamin A toxicity in wild‐caught vervet monkeys (Cercopithecus aethiops) after two years of captivity

• Published in: The FASEB journal 2006-03, Vol.20 (4), p.A135-A135
• Main Authors: Mills, Jordan P, Tanumihardjo, Sherry A
• Format: Article
• Language: English
• ISSN: 0892-6638; 1530-6860
• DOI: 10.1096/fasebj.20.4.A135-b

Non‐human primates are excellent models for biomedical research because of their genetic similarities to humans. Yet, nutrient requirement studies for these animal models have not been systematically performed. Primate lab diets typically contain high vitamin A (VA) concentrations when compared to human recommended intakes. In the current study, liver and serum samples from adult vervet monkeys (Cercopithecus aethiops) (n = 13) were analyzed for VA content. The mean weight of the monkeys at kill was 3.9 ± 0.6 kg. Samples were obtained from the Oregon National Primate Research Center. These monkeys were wild‐caught and held in captivity for two years, during which they consumed a standard primate lab diet. HPLC analysis revealed a mean VA concentration of 14.6 ± 2.3 μmol retinol/g liver. Subtoxicity in humans is defined as 1 μmol/g liver. Mean serum retinol concentration (0.93 ± 0.21 μmol/L) was not elevated. Hypertrophy and hyperplasia of the hepatic stellate cells were observed. Elevated hepatic VA concentrations in conjunction with stellate cell abnormalities are evidence of VA toxicity. Similar results were shown in lifetime captive rhesus monkeys from the Wisconsin Primate Research Center with liver reserves > 17 μmol/g. Thus, excessive VA in primate chow affects multiple primate centers. Although the ramifications of toxic VA status in experimental monkeys are not known, a concerted effort should be made to reformulate these diets to be lower in preformed VA. Ideally, diet should include more provitamin A sources as monkeys in the wild are predominantly frugivorous. Supported by NIH‐NIDDK61973.