Mutagenicity And Subchronic Toxicity Study Of Tea Saponin In Rats

Objective: Subchronic toxicity test by oral in Wistar rats and three mutagenicitytests were adopted to ascertain the subchronic toxic characteristic and themutagenicity of TS, then further, to provide scientific basis for the safe evaluationand the toxicological data for TS.Methods:88Wistar rats were divided into4groups by weight, animals were fedwith the diets containing TS (0mg/kg,20mg/kg,100mg/kg, and500mg/kg) for90days. During the study, Clinical signs, body weights, food consumption, organweights, serum biochemistry, urinalysis, and histopathology were observed andrecorded. Three tests were conducted to detect the mutagenicity of TS.There weremice bone marrow polychromatic erythrocytes micronucleus, Ames assay and micetesticle cell chromosome aberration test.Results:1.During the study, no death and obvious abnormal changes were observedfor the subjects. Compared with the control group, body weights of the males incase group significantly decreased in the high-dose group (P<0.05) from the9thweeks. The WBC concentration in the males significantly increased in the high-dosegroup (P<0.05), index of brain, spleen and lung increased (P<0.05). Lung index ofthe males in the medium group increased (P<0.05).ALB concentration of thefemales in the high dose group was decreased, significant increased of ALT, ALPand CHE (P<0.05).2.At the dosage from2.5to50mg/ml, micronucleus rate had no significantdifference in comparison with the negative and the ratio of PCE/(PCE+NCE) above0.5,which means TS couldn’t induce micronucleus formation and inhibit bonemarrow cell-cleavage. At the5~5000μg/plate with TS,there were no increases in thebacterial colony counts of reverse mutation, and the experimented groups’ colonies didn’t exceed two times than the negative controls’. There were no dose-responsesrelationships among the case groups. The results of Ames tests were negative. Atthe dosage from125to500mg/ml, the rate of mice testis cell chromosomeaberration induced by the case groups with TS didn’t have significant differencecompared with the negative group, and all values were within the normal range ofthe laboratory measured values. That means TS couldn’t induce chromosomeaberrations in male germ cells of mice at the certain dosages ranges.Conclusion:1.The no observable adverse effect levels (NOAEL) and lowestobserved adverse effect level (LOAEL) of tea saponin in subchronic toxicity test byoral exposure were20,100mg/kg BW.2. The results suggested that TS may have potential impacts on the rats’ weight andlung.3.Results from the three mutagenicity tests were negative, which showed that TShad no obviously mutagenic effect.