Cytotoxicity and inflammation induced by Philodryas patagoniensis venom.

The Green racer Philodryas patagoniensis is a snake species from South America and accidents with this genus are often neglected. Therefore, this study aimed to evaluate the toxicological, cytotoxic, and inflammatory potential of P. patagoniensis venom (PpV). The experimental model Artemia salina was used to determine toxicity through the median lethal dose (LD50). Cell viability and genotoxicity were evaluated in human mononuclear cells using the Trypan blue test and the Comet assay, respectively. To assess inflammation, mice had the ventral surface of the right hind paw injected with saline, formalin, and three different concentrations of venom (1, 1.5, and 2 µg. 50 µL-1). LD50 in A. salina was 461 µg. mL-1. PpV caused a significant increase in cell death and genotoxicity in human mononuclear cells at two concentrations (575 and 1150 µg. mL-1). PpV shown also to be a strong agent causing nociception in mice. Paw edema totaled four days at 1.5 µg. 50 µL-1. The hyperalgesia caused by the venom had a long duration in mice, lasting eight days at all concentrations evaluated. Thus, we evaluated for the first time the toxicological potential of PpV in A. salina model and in leukocytes. We concluded that systemic oxidative stress, which we infer to be in the genesis of cytotoxicity and genotoxicity observed in vitro, and the inflammatory process are part of the pathways that trigger the venom damage cascades. Relevant data for both scientific research and clinical medicine. Nonetheless, studies are needed to elucidate these mechanisms.

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.

In vivo effects of exposure to Golden trumpet Handroanthus chrysotrichus in mice.

The Golden trumpet Handroanthus chrysotrichus is a tree that presents beneficial health properties against various diseases. Thus, this study aims to verify the toxicity of H. chrysotrichus bark extract, observing the effects of exposure to this extract in mice. For this, mice were separated in groups: saline (sterile solution .9%); H. chrysotrichus crude extract (HCCE) 10; HCCE 50, and HCCE 100 mg. kg-1 (p.o.). We analyzed HCCE effects on acute (single exposure) and subchronic protocol (14 days exposure). After both exposures, acute, and subchronic, we collected samples from blood, brain, liver, and kidney tissues for biochemical evaluation. In addition, after subchronic exposure, we performed behavioral tests. Acute exposure caused an increase of lipid peroxidation in liver tissue. Moreover, we observed a significant carbonyl increase in liver and brain tissues from HCCE 50 mg. kg-1. Kidneys presented carbonyl increase in mice treated with the highest concentration. Besides, creatinine increased in the group of the acute exposure at HCCE 100 mg. kg-1. Total leukocyte count decreased in all concentrations tested. Sub-chronic exposure at HCCE 100 mg. kg-1 caused a decrease in the number of crossing and an increase in its self-grooming frequency in the open field test. In this exposure, the brain and liver had a significant increase in carbonyl levels in all concentrations. We concluded that H. chrysotrichus cause behavioral and biochemical alterations in mice. HCCE primary targets seem to be the liver, kidneys, and white cells.

Toxicological parameters of aqueous residue after using Plectranthus neochilus for 2,4-D phytoremediation.

Phytoremediation is a technique that reduces the impact and environmental toxicity of toxic agents. Plectranthus neochilus, a species of aromatic plant, has already promoted phytoremediation of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D). In addition, it was unclear whether the degradation of 2,4-D alone allows for a non-toxic environment (decontamination efficiency). Therefore, the aim of the present study was to verify the changes of the volatile compounds and concentrated essential oil of P. neochilus after phytoremediation of 2,4-D and the subsequent antibacterial activity of this essential oil concentrate. In addition, the toxicity of the plant's tea and the aqueous medium (waste) after the decontamination of 2,4-D was analyzed. The exposure to 2,4-D did not cause many changes in the volatile compounds, nor in the essential oil concentrate from the plant. Therefore, this essential oil concentrate can be used as an antimicrobial after phytoremediation. Regarding the use of this plant in tea form, it was found to be unsafe, even after phytoremediation, as this tea was toxic to the Drosophila melanogaster model (death of up to 100% of flies). The aqueous medium after 2,4-D phytoremediation became less toxic than the initial one (bioassays with Artemia salina and Allium cepa in the waste groups). However, the efficiency of phytoremediation with this plant must be improved. Therefore, we are performing new studies with P. necohilus and 2,4-D in aqueous medium.