Sida tuberculata: In vitro cytotoxicity and in vivo anti-inflammatory effect.

ETHNOPHARMACOLOGICAL RELEVANCE: Sida tuberculata R. E. Fries (Malvaceae) is a pioneer species considered a weed in farm fields in Southern Brazil. Widely distributed in South Brazil, S. tuberculata is popularly used to treat inflammatory conditions. AIMS OF THE STUDY: The current study aimed to assess the in vitro cytotoxic and in vivo anti-inflammatory properties of S. tuberculata. MATERIALS AND METHODS: Initially, extracts obtained from leaves (STLE) and roots (STRE) were submitted to cytotoxicity tests using human leukocytes (non-malignant cell line) and HepG2 and MCF-7 (tumor cell lines). In sequence, anti-inflammatory properties were investigated against carrageenan-induced peritonitis model. RESULTS: In vitro analyses displayed a significant decrease in human leukocytes viability without genotoxic damage. IC50 results from tumor cells presented significant decrease in cell viability, slightly more pronounced for STRE. In addition, STLE significantly inhibited the inflammatory and oxidative parameters (TBARS, NPSH, SOD, MPO activity, cell influx, and cytokines release). CONCLUSION: Our findings indicate S. tuberculata extracts have cytotoxic potential more pronounced on tumor cell lines, as well as leaves extract shows a significant reduction in acute inflammation process, as already reported for Sida genus and specifically for this species.

Fumonisin B1 induces toxicity in human leukocytes at low concentrations: Are computational studies effective to determine biosafety?

Fumonisin B1 is a mycotoxin produced by Fusarium verticillioides and Fusarium proliferatum found in various crops, particularly maize. Besides carcinogenicity, other manifestations have been registered in different animals and in humans. In the case of humans, epidemiological studies have reported high prevalence of esophageal cancer in populations exposed to fumonisins. This study aimed to evaluate the minimum concentration of FB1 capable of inducing cytotoxicity (cell viability test), genotoxicity (comet assay) and mutagenicity (micronucleus) in cultured human leukocytes and to evaluate the effectiveness of in silico tests to predict FB1 toxicity. All concentrations analyzed (200; 100; 50; 5; 0.5; 0.05; 0.005 µg/mL and 300; 30; 3; 1; 0.1; 0.01 fg/mL) except the lowest demonstrated dose-dependent toxicity in all parameters analyzed (p < 0.05 to p < 0.0001). As for predictions, only the Lazar software showed carcinogenicity of FB1 for rats. Thus, it is evident that FB1 is able to induce dose-dependent damage at low concentrations, and that computational tests, although desirable for prediction, are not effective as biological tests to determine toxicity, at least of FB 1 and within the experimental conditions tested.

CdCl2 has zero-order kinetic cellular influx and induces cytotoxicity and genotoxicity at low concentrations in human leukocytes in vitro / El CdCl2 tiene un influjo celular cinético de orden cero e induce citotoxicidad y genotoxicidad a bajas concentraciones en leucocitos humanos in vitro

SUMMARY Cadmium (Cd2+) is a nonessential heavy metal that possesses a high capacity of bioaccumulation and exhibits toxic characteristics even at low concentrations. This study evaluated the genotoxicity and cytotoxicity in human leukocytes in vitro after exposure to a lower range of Cd2+concentration (1-25 (g/mL) using an unprecedented strategy by correlating between intracellular Cd2+ levels after exposure and cellular damage. Results demonstrated that Cd2+exposure from 5 to 25 fig/mL significantly increased the unviability of leukocytes, as well as the DNA damage, which was dose-dependent. The intracellular Cd2+ levels in leukocytes ranged from 9.85 to 94.38 pg/cell, and cytotoxicity and genotoxicity were induced at a concentration of24.22 pg/cell. The relationship between exposure concentration and intra-cellular Cd2+ levels suggests that its influx occurs in human leukocytes under zero-order kinetics.

RESUMEN El cadmio (Cd2+) es un metal pesado no esencial que posee una alta capacidad de bioacumulación y presenta características tóxicas incluso en bajas concentraciones. Este estudio evaluó la genotoxicidad y la citotoxicidad en leucocitos humanos in vitro después de la exposición a un rango inferior de concentración de Cd2+ (1-25 (g / mL) mediante una estrategia sin precedentes al correlacionar los niveles intracelulares de Cd2+ después de la exposición y el daño celular. Los resultados demostraron que la exposición a Cd2+ de 5 a 25 (g/mL aumentó significativamente la inviabilidad de los leucocitos, así como el daño en el ADN, que era dependiente de la dosis. Los niveles intracelulares de Cd2+ en leucocitos oscilaron entre 9,85 y 94,38 pg/célula, y se indujo la citotoxicidad y la genotoxicidad a una concentración de 24,22 pg/ célula. La relación entre la concentración de la exposición y los niveles intracelulares de Cd2+ sugiere que su influjo se produce en leucocitos humanos bajo una cinética de orden cero.