Evaluation of Caspase-3 and Ki-67 expression in squamous cell hyperplasia of the stomach induced by Platycodi radix water extract in Sprague-Dawley rats.

Platycodi radix is widely used in traditional herbal medicine for the treatment of bronchitis, asthma, pulmonary tuberculosis, hypertension, hyperlipidemia, and diabetes. This study aimed to investigate cell proliferation (Ki-67) and apoptosis (Caspase-3) potential in squamous cell hyperplasia of the stomach induced by a Platycodi radix water extract in a subchronic toxicity study. One hundred formalin-fixed, paraffin-embedded stomach tissues of rats treated with Platycodi radix at doses of 0, 500, 1,000, and 3,000 mg/kg body weight/day were used for the analysis. They were conventionally stained using hematoxylin and eosin (H&E) and immunohistochemically (IHC) stained using caspase-3 and Ki-67 antibodies. The incidence of squamous cell hyperplasia was significantly increased in the 3,000 mg/kg b.w./day treatment group in both sexes (p<0.01). However, the hyperplastic change was completely repaired after 4 weeks of recovery period. Ki-67 expression was similar in all groups, with no statistically significant differences among the groups. Caspase-3 expression was significantly increased in both sexes in the 3,000 mg/kg b.w./day treatment group (p<0.01), compared with the vehicle control groups, and then reduced to normal levels in the recovery groups in both sexes. In conclusion, this study showed that squamous cell hyperplasia induced by the Platycodi radix water extract in the limiting ridge of the stomach is not considered to be abnormal proliferative change; as a result, squamous cell hyperplasia is considered to be a non-adverse effect when induced by the oral administration of the Platycodi radix water extract once daily for 13 weeks in rats.

Assessment of the 4-week repeated-dose oral toxicity and genotoxicity of GHX02.

Herbal medicines are widely utilized for disease prevention and health promotion. GHX02 consists of mixtures including Gwaruin (Trichosanthes kirilowii), Haengin (Prunus armeniaca), Hwangryeon (Coptis japonica) and Hwangkeum (Scutellaria baicalensis). It has been purported to have therapeutic effectiveness in cases of severe bronchitis. Non-clinical safety testing comprised a single-dose oral toxicity study and a 28-day repeated-dose oral toxicity study with a 14-day recovery period, and genotoxicity was assessed by a bacterial reverse mutation test, in vitro chromosomal aberration test, in vivo mouse bone marrow micronucleus test and single cell gel electrophoresis assay (comet assay). In the single-dose oral toxicity study, the approximate lethal dosage is estimated to be higher than 5000 mg/kg in rats. Thus, the dosage levels were set at 0, 1250, 2500 and 5000 mg/kg/day in the 28-day repeated-dose oral toxicity study, and 10 male rats and 10 female rats/dose were administered GHX02. No clinical signs of toxicological significance were recorded in any animal during the dosing and the observation period in the single-dose study. The no-observed-adverse-effect level of GHX02 was 5000 mg/kg/day when administered orally for 28 days to male and female Sprague-Dawley rats. Despite increases in the frequencies of cells with numerical chromosomal aberration in the in vitro test, the increases were not considered relevant to the in vivo genetic risk. Except for the increase of in vitro numerical chromosomal aberration, clear negative results were obtained from other genetic toxicity studies.

Evaluation of 13-week repeated oral dose toxicity of Areca catechu in F344/N rats.

This study investigated the potential toxicity of the Areca catechu water extract after 13-week repeated oral administration at 0, 166.7, 500, and 1500 mg/kg/day in rats. During the study period, clinical signs, mortality, body weight, food consumption, water consumption, urinalysis, estrous cycle, sperm count and motility, ophthalmoscopy, hematology, serum biochemistry, gross pathology, organ weights, and histopathology were examined. At 1500 mg/kg/day, both sexes exhibited an increase in the incidence of abnormal clinical signs, which included, decreased body weight gain and food consumption, and increased urine bilirubin, ketone bodies, specific gravity, and protein and kidney weight. An increase in liver weight and estrous cycle alterations was observed in females. Serum biochemical and histopathological investigations revealed an increase in the levels of serum aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase, and the incidence of hepatic necrosis in females. At 500 mg/kg/day, an increase in the incidence of abnormal clinical signs including diarrhea and soiled perineal region, was observed in both sexes. No treatmentrelated effects were observed at 166.7 mg/kg/day. Under the present experimental conditions, the target organs were determined to be the liver, kidney, and female reproductive system in rats. The no-observedeffect level was considered to be 166.7 mg/kg/day in rats.

Single and 90-day repeated oral dose toxicity studies of fermented Rhus verniciflua stem bark extract in Sprague-Dawley rats.

Fermented Rhus verniciflua stem bark (FRVSB) extract, an urushiol-free extract of Rhus verniciflua Stokes (RVS) fermented with Fomitella fraxinea, has various biological activities. The present study was carried out to investigate the potential toxicity of the FRVSB extract following single and repeated oral administration to Sprague-Dawley rats. In the single dose toxicity study, the FRVSB extract was administered orally to male and female rats at single doses of 0, 2500, 5000, and 10,000mg/kg. No animals died and no toxic changes were observed in clinical signs, body weight, and necropsy findings during the 15-day period following administration. In the repeated dose toxicity study, the FRVSB extract was administered orally to male and female rats for 90days at doses of 0, 556, 1667, and 5000mg/kg/day. There were no treatment-related adverse effects in clinical signs, body weight, food and water consumption, ophthalmic examination, urinalysis, hematology, serum biochemistry, necropsy findings, organ weight, and histopathology at any dose tested. The approximate lethal dose of the FRVSB extract was >10,000mg/kg in both genders, the oral no-observed-adverse-effect level of the FRVSB extract was >5000mg/kg/day in both genders, and no target organs were identified.