Acute and sub-acute toxicity study of ethanol extract from Nectandra leucantha Nees & Mart. (Lauraceae) barks.

Nectandra leucantha has been used in traditional medicine. Several metabolites isolated from N. leucantha extracts displayed immunomodulatory, antileishmanial properties, but the determination of the toxicological profile in mammals has not previously been performed. In this study, the ethanol extract from N. leucantha barks (EENl) was characterized by HPLC/HRESIMS. To study acute toxicity, female mice received EENl in a single dose of 100, 300, 1000, or 2000 mg/kg bw. Later, sub-acute toxicity was introduced in female and male mice by oral gavage at 100, 500 or 1000 mg/kg bw for 28 consecutive days. Hematological and biochemical profiles from the blood as well as histological analysis from the liver and kidney were performed. The HPLC/HRESIMS analysis of the EENl revealed the presence of six neolignans chemically related to dehydrodieugenol B. In the oral acute and sub-chronic studies, EENl did not produce in all doses evaluated any alteration in behavior, biochemical, hematological, body weight gain and food intake or sudden death in Swiss mice. In addition, histopathological data did not reveal any disturbance in liver and kidney morphology after 28 days of EENl treatment. Our results indicate that EENl at dosage levels up to 2000 mg/kg bw is non-toxic and can be considered safe for mammals.

Non-clinical repeated dose 28-day oral toxicity, reproductive toxicity and cytotoxicity studies of the polar fraction of Parkinsonia aculeata aerial parts extract.

This study was aimed to evaluate toxicity in repeated doses for 28 days, reproductive toxicity and cytotoxicity of a polar fraction obtained from the hydroethanolic extract of Parkinsonia aculeata (PfrHEPA) in experimental models. To perform the toxicity test in repeated doses for 28 days, male and female Wistar rats were treated via orogastric for 28 days with PfrHEPA (35, 70 or 140 mg/kg) according to the guidelines established by the Organisation for Economic Co-operation and Development (OECD) number 407 (1995). For assessment, the impact of PfrHEPA on the reproductive output various parameters were measured, including maternal weight, no. of pregnant females, female fertility index (%), gestation lengthtime, implantation sites, litter size and placental index of test animals. The cytotoxicity of PfrHEPA was performed on the tumor lines NCI-H292 (human lung carcinoma), HL-60 (human promyelocytic leukemia) and HCT-116 (colorectal cancer). In the repeated dose toxicity test for 28 days, no mortality was observed in the male and female rats treated with PfrHEPA as well as morphological changes and biochemical and hematological parameters. In the reproductive toxicity test, no abnormalities were observed related to the toxicological parameters in both mothers and offspring. Regarding the cytotoxicity assay, the PfrHEPA fraction did not demonstrate significant cytotoxic effect on the cell lines analyzed. The present results suggest the use of PfrHEPA is safe and well tolerated in rats. Further studies are planned to identify and purify the active compounds for subsequent in vivo evaluation.

Safety assessment of Bauhinia cheilantha Bong. Steud leaves extract: acute, sub-acute toxicity, antioxidant, and antihemolytic evaluations.

Bauhinia cheilantha (Fabaceae), known popularly as pata-de-vaca and mororó has been largely recommended treating several diseases in folk medicine. However, information on safe doses and use is still scarce. The goal was to evaluate in-vitro antioxidant and antihemolytic and also acute and sub-acute toxicity effects of hydroalcoholic extract from B. cheilantha leaves (HaEBcl). The identification of the compounds in the HaEBcl was performed by ultra-performance liquid chromatography coupled with a diode array detector and quadrupole time-of-flight mass spectrometry. Antioxidant and hemolytic activity of HaEBcl was evaluated in vitro. To study acute toxicity, female mice received HaEBcl in a single dose of 300 and 2.000 mg/kg. Later, sub-acute toxicity was introduced in both female and male mice by oral gavage at 300, 1000, or 2000 mg/kg for 28 consecutive days. Hematological and biochemical profiles were created from the blood as well as from histological analysis of the liver. HaEBcl is rich in flavonoids (quercitrin and afzelin), has no hemolytic effects and moderate antioxidant effects in vitro. Acute toxicity evaluation showed that lethal dose (LD50) of HaEBcl was over 2000 mg/kg. Sub-acute toxicity testing elicited no clinical signs of toxicity, morbidity, or mortality. The hematological and biochemical parameters discounted any chance of hepatic or kidney toxicity. Furthermore, histopathological data did not reveal any disturbance in liver morphology in treated mice. Results indicate that HaEBcl has no hemolytic and moderate antioxidant effects in vitro. In addition, HaEBcl dosage levels up to 2000 mg/kg are nontoxic and can be considered safe for mammals.