Regulatory toxicology and pharmacology : RTP
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Regul. Toxicol. Pharmacol. · Aug 2004
Embryotoxicity and teratogenicity study with neohesperidin dihydrochalcone in rats.
The embryotoxicity/teratogenicity of neohesperidin dihydrochalcone (NHDC) was examined in Wistar Crl:(WI)WU BR rats. NHDC was fed at dietary concentrations of 0, 1.25, 2.5 or 5 to groups of 28 mated female rats from day 0 to 21 of gestation. At Cesarean section 25, 22, 23, and 23 rats were found to be pregnant in the control, low-, mid-, and high-dose group, respectively. ⋯ Examination of the fetuses for external, visceral, and skeletal changes did not reveal any fetotoxic, embryotoxic or teratogenic effects of NHDC. In conclusion, no adverse effects were observed at NHDC levels of up to 5% of the diet, the highest dose level tested, at which the rats consumed about 3.3g/kg body weight/day. The observed cecal enlargement is a well-known physiological, adaptive response to the ingestion of high doses of a low-digestible substance and is generally accepted to lack toxicological relevance.
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Regul. Toxicol. Pharmacol. · Aug 2004
Prenatal developmental toxicity study with 7-hydroxymatairesinol potassium acetate (HMRlignan) in rats.
Plant lignan 7-hydromatairesinol, a novel precursor of the mammalian lignan enterolactone was evaluated in a prenatal developmental toxicity study conducted in the Wistar rat. Mated female rats were fed diets containing 0, 0.25, 1, and 4% (w/w) of 7-hydroxymatairesinol in the form of potassium acetate complex (HMRlignan; potassium acetate level approximately 20% w/w within the preparation) for days 0-21 of gestation. Test substance intake was calculated to be 0.14-0.18, 0.46-0.74, and 1.19-2.93 g/kg body weight/day for the low, mid, and high-dose groups, respectively. ⋯ Body weights of the remaining animals of the high-dose group were decreased. Food consumption was decreased in all treatment groups during the first three days of the gestation period as a result of decreased palatability of the feed. In conclusion, the no-observed-effect level (NOEL) for maternal effects was 1%, whereas the NOEL for fetal development following daily oral HMRlignan administration throughout the gestation was equivalent to 4% in the diet.