A 90-Day Repeated Oral Dose Toxicity Study of Alismatis Rhizoma Aqueous Extract in Rats

Toxicity study of silica nanoparticles following 94-day repeated oral administration in Sprague Dawley rats

This study was designed to investigate the toxic response of Sprague Dawley (SD) rats following oral administration of different doses of silica nanoparticles (SiNPs) for 94 consecutive days, as well as the recovery after 30 days of withdrawal. Rats were orally administered SiNPs at dosages of 0, 125, 250, and 500 mg/kg /day once a day for 94 continuous days. By the end of the study, there were no fatalities in any of the experimental animals that received SiNPs orally. Under the tested doses, no adverse effects related to SiNPs treatment were observed in a comprehensive assessment of several dimensions, including clinical signs, body weight changes, food consumption, hematological parameters, blood biochemical indices, urinalysis, organ weights and coefficients, and gross and histopathology. Based on the current study results, the No Observed Adverse Effect Level (NOAEL) for repeated oral administration of SiNPs in rats for 94 consecutive days was designated as 500 mg/kg/day.

Pharmacological Properties and Molecular Targets of Alisol Triterpenoids from Alismatis Rhizoma

More than 100 protostane triterpenoids have been isolated from the dried rhizomes of Alisma species, designated Alismatis rhizoma (AR), commonly used in Asian traditional medicine to treat inflammatory and vascular diseases. The main products are the alisols, with the lead compounds alisol-A/-B and their acetate derivatives being the most abundant products in the plant and the best-known bioactive products. The pharmacological effects of Ali-A, Ali-A 24-acetate, Ali-B, Ali-B 23-acetate, and derivatives have been analyzed to provide an overview of the medicinal properties, signaling pathways, and molecular targets at the origin of those activities. Diverse protein targets have been proposed for these natural products, including the farnesoid X receptor, soluble epoxide hydrolase, and other enzymes (AMPK, HCE-2) and functional proteins (YAP, LXR) at the origin of the anti-atherosclerosis, anti-inflammatory, antioxidant, anti-fibrotic, and anti-proliferative activities. Activities were classified in two groups. The lipid-lowering and anti-atherosclerosis effects benefit from robust in vitro and in vivo data (group 1). The anticancer effects of alisols have been largely reported, but, essentially, studies using tumor cell lines and solid in vivo data are lacking (group 2). The survey shed light on the pharmacological properties of alisol triterpenoids frequently found in traditional phytomedicines.

Toxicological assessment of enzyme-treated Zizania latifolia extract: Oral toxicology and genotoxicity in rats

Zizania latifolia Turcz. has long been used as a food source in Southeast Asia. The grains, stems, and leaves of Z. latifolia and its major component, tricin, have also been studied to determine their biological activities. Previously, we hydrolyzed the aerial part of Z. latifolia using an enzyme mixture to maximize the tricin content of the Z. latifolia extract. However, the safety of enzyme-treated Z. latifolia extract (ETZL; DermaNiA™) has not yet been determined. In this study, we performed an in vivo 90-day repeated-dose evaluation and genotoxicity study to assess the toxicological potential of ETZL. EZTL did not exhibit genotoxicity in the bacterial reverse mutation test, in vitro chromosomal aberration assay, or in vivo micronucleus test. Moreover, no changes in body weight or hematological and serum biological parameters were observed in male or female rats under high-dose EZTL treatment (5000 mg/kg body weight (bw)/day) for 90 days with a 4-week recovery period. Significant changes were noted in the forestomach, kidneys, and adrenal glands in the test groups, but these changes, or tendency for recovery, were not observed in the recovery group. Based on these data, the no adverse effect level was determined to be 1250 mg/kg bw/day in rats.

Subchronic Toxicity Evaluation of Aluminum Oxide Nanoparticles in Rats Following 28-Day Repeated Oral Administration

Several studies on the potential adverse effects of aluminum oxide nanoparticles (Al₂O₃NPs) have reported conflicting results. The present study investigated the potential adverse effects of Al₂O₃NPs in Sprague-Dawley rats following 28-day repeated oral administration. In addition, we aimed to determine the target organ and no-observed-adverse-effect level (NOAEL) of Al₂O₃NPs. Al₂O₃NPs was administered once daily by gavage to male and female rats at dose levels of 0, 500, and 1000 mg/kg/day for 28 days. There were no treatment-related adverse effects as indicated by the clinical signs, body weight, food consumption, urinalysis, ophthalmology, hematology, serum biochemistry, gross pathology, organ weight, and histopathology at all the tested doses. Under the experimental conditions of the present study, 28-day repeated oral administration of Al₂O₃NPs at doses of up to 1000 mg/kg/day did not induce any treatment-related systemic toxicity in male and female rats. The NOAEL of Al₂O₃NPs was set at 1000 mg/kg/day in both male and female rats and no target organs were identified.

Exotic Medicinal Plants Used in Brazil with Diuretic Properties: A Review

Several exotic plants (non-native) are used in Brazilian traditional medicine and are known worldwide for their possible diuretic actions. Among the wide variety of plants, standing out Achillea millefolium L., Camellia sinensis L. Kuntze, Crocus sativus L., Hibiscus sabdariffa Linn., Petroselinum crispum (Mill.) A.W. Hill, Taraxacum officinale (L.) Weber, and Urtica dioica L., whose effects have already been the subject of some scientific study. In addition, we also discussed other exotic species in Brazil used popularly, but that still lack scientific studies, like the species Arctium lappa L., Carica papaya L., Catharanthus roseus (L.) G. Don, Centella asiatica (L.) Urb, Citrus aurantium L., and Persea americana Mill. However, generally, clinical studies on these plants are scarce. In this context, different plant species can be designated for further comprehensive studies, therefore, promoting support for developing an effective medicine to induce diuresis.

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.

Four-Week Repeated Intravenous Dose Toxicity of Self-Assembled-Micelle Inhibitory RNA-Targeting Amphiregulin in Mice

The present study investigated the potential subchronic toxicity of self-assembled-micelle inhibitory RNA-targeting amphiregulin (SAMiRNA-AREG) in mice. The test reagent was administered once-daily by intravenous injection for 4 weeks at 0, 100, 200, or 300 mg/kg/day doses. Additional recovery groups (vehicle control and high dose groups) were observed for a 2-week recovery period. During the test period, mortality, clinical signs, body weight, food consumption, ophthalmology, urinalysis, hematology, serum biochemistry, gross pathology, organ weight, and histopathology were examined. An increase in the percentages of basophil and large unstained cells was observed in the 200 and 300 mg/kg/day groups of both sexes. In addition, the absolute and relative weights of the spleen were higher in males given 300 mg/kg/day relative to the concurrent controls. However, these findings were considered of no toxicological significance because the changes were minimal, were not accompanied by other relevant results (eg, correlating microscopic changes), and were not observed at the end of the 2-week recovery period indicating recovery of the findings. Based on the results, SAMiRNA-AREG did not cause treatment-related adverse effects at dose levels of up to 300 mg/kg/day in mice after 4-week repeated intravenous doses. Under these conditions, the no-observed-adverse-effect level of the SAMiRNA-AREG was ≥300 mg/kg/day in both sexes and no target organs were identified.

Evaluation of 28-day repeated oral dose toxicity of SUNACTIVE Zn-P240 in rats

This study was conducted to investigate the potential toxicity of repeated oral dose of SUNACTIVE Zn-P240, a new type of zinc supplement, in Sprague-Dawley rats. SUNACTIVE Zn-P240 was administered once daily by gavage at doses of 0, 500, 1000, and 2000 mg/kg/day for each group over a 28-day period. At 2000 mg/kg/day, there were increases in serum alkaline phosphatase (ALP) and alanine aminotransferase, liver weight, histopathological changes in stomach, liver, and pancreas and decreases in body weight, food consumption, hemoglobin, hematocrit, mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration, total protein (TP), and albumin. At 1000 mg/kg/day, there was an increase in the serum ALP level and there were decreases in the MCV, MCH, and TP. There were no treatment-related adverse effects in the 500 mg/kg/day group. Under the present experimental conditions, the target organs in rats were determined to be the stomach, pancreas, liver, and erythrocyte and the no-observed-adverse-effect level (NOAEL) in rats was considered to be 500 mg/kg/day.

Evaluation of 13-week subchronic toxicity of Platycodon grandiflorus (Jacq.) A.DC. root extract in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Platycodi radix is widely used in traditional herbal medicine for bronchitis, asthma, pulmonary tuberculosis, hypertension, hyperlipidemia, and diabetes. However, data on safety of Platycodi radix are insufficient.

AIM OF THE STUDY

The present study was performed to evaluate the potential subchronic toxicity of Platycodi radix water extract through a 13-week repeated oral dose experiment in Sprague-Dawley rats.

MATERIALS AND METHODS

Forty male and 40 female rats were randomly assigned to four experimental groups: three treatment groups receiving 300, 1000, and 3000 mg/kg/day of Platycodi radix water extract and a vehicle control group receiving sterile distilled water for 13 weeks.

RESULTS

Repeated oral administration of the Platycodi radix water extract to rats resulted in an increased incidence of centrilobular hepatocellular hypertrophy in the liver, diffuse follicular cell hypertrophy in the thyroid gland, and squamous hyperplasia of the limiting ridge in the stomach at dose levels of ≥500 mg/kg/day of both genders. However, these findings are considered be adaptive non-adverse changes because these findings were observed without organ weight change or clinical pathology alterations. No treatment-related effects on clinical signs, body weight, food and water consumption, ophthalmic examination, urinalysis, hematology, serum biochemistry, necropsy findings, and organ weights were observed at any dose tested.

CONCLUSION

Under the present experimental conditions, the no-observed-adverse-effect level of the Platycodi radix water extract was considered to be ≥ 3000 mg/kg/day in rats, and no target organs were identified.

A 13-week subchronic toxicity study of a Dioscorea Rhizome water extract in rats

Dioscorea Rhizome is widely used as a traditional herbal medicine to treat asthma, diarrhea, cough, bronchitis, spermatorrhea, leukorrhea, and rheumatoid arthritis. This study investigated the potential subchronic toxicity of a D. Rhizome water extract (DRWE) after repeated oral administration at 0, 800, 2000, and 5000 mg/kg/day in rats for 13 weeks. During the study period, clinical signs, mortality, body weight, food consumption, water consumption, urinalysis, ophthalmoscopy, hematology, serum biochemistry, gross pathology, organ weights, and histopathology were examined. The 13-week repeated oral administration of DRWE to rats resulted in an increased incidence of zona glomerulosa hypertrophy and hyperplasia in the adrenal gland at dose levels of ≥2000 mg/kg/day in both sexes. However, these findings are considered as non-adverse adaptive changes because of minimal histological changes in the lesions, which were not accompanied by any corresponding alterations in serum electrolytes and adrenal gland weight. No treatment-related adverse effects on clinical signs, body weight, food and water consumption, ophthalmic examination, urinalysis, hematology, serum biochemistry, necropsy findings, and organ weights were observed at any dose tested. Under the present experimental conditions, the no-observed-adverse-effect level of the DRWE was considered to be 5000 mg/kg/day in both sexes, and no target organs were identified.

Evaluation of 28-day repeated oral dose toxicity of aluminum chloride in rats

The present study investigated the potential adverse effects of aluminum chloride (AlCl₃) following a 4-week repeated oral administration in Sprague-Dawley rats. The test article was administered once daily by gavage to male and female rats at dose levels of 0, 100, 300, and 900 mg/kg/day for 4 weeks. After administration of AlCl₃ at 900 mg/kg/day, treatment-related systemic toxicity manifested as significant increases in salivation incidence, neutrophil percentage, reticulocytes, serum triglyceride, adrenal gland and liver weights, and single-hepatocyte necrosis, as well as significant decreases in body weight gain, food intake, hemoglobin, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration (MCHC), lymphocyte percentage, serum total protein and albumin, and thymus weight in male rats; and significant increases in salivation incidence, serum triglyceride, and liver weight, as well as a significant decrease in lymphocyte percentage in female rats. At 300 mg/kg/day, a significant decrease in MCHC was found in male rats, but not in female rats. However, this finding was not toxicologically significant because the reduction was minimal and was not accompanied by changes in any other parameters. No treatment-related effects were observed in the 100 mg/kg/day group of both genders. Under the experimental conditions of this study, the target organs of AlCl₃ were determined to be the blood, liver, and thymus in rats. The no-observed-adverse-effect level was found to be 300 mg/kg/day in rats of both genders.

Subchronic toxicity evaluation of ethanol extract of Cassia tora L. seeds in rats

Cassia tora Linn. is an annual or perennial plant of the Fabaceae/Leguminosae family. It is used in traditional medicine for various biological activities including anti-constipation, anti-inflammatory, visual acuity, and hepato-protective activities. The present study was carried out to investigate the potential toxicity of C. tora L. seed ethanol extract (CTSEE) following a 13-week repeated oral administration to Sprague-Dawley rats. CTSEE was administered orally to male and female rats for 13 weeks at 0 (control), 500, 1000, and 2000 mg/kg/day (n = 10, for male and female rats for each dose). Additional recovery groups from the control group and high dose group were observed for a 4-week recovery period. At the end of the treatment and recovery periods, animals were sacrificed, and their organs were weighed and blood samples collected. There were no treatment-related adverse effects in clinical signs, body weight, food consumption, estrous cycle, sperm parameters, urinalysis, hematology, serum biochemistry, necropsy findings, organ weight, and histopathology at any doses tested. Under the present experimental conditions, the no-observed-adverse-effect level of the CTSEE was >2000 mg/kg/day in both genders, and no target organs were identified.