Phytochemical profile and determination of cytotoxicity, acute oral toxicity, genotoxicity, and mutagenicity of aqueous and ethanolic extracts of Pseudobombax marginatum (A. St.-Hil.) A. Robyns.

Pseudobombax marginatum, popularly known as "embiratanha," is widely used by traditional communities as anti-inflammatory and analgesic agent. This study aimed to determine the phytochemical profile as well as cytotoxicity, acute oral toxicity, genotoxicity, and mutagenicity attributed to exposure to aqueous (AqEx) and ethanolic (EtEx) extracts of embiratanha bark. Phytochemical screening was conducted using thin-layer chromatography (TLC). Cell viability was analyzed using MTT assay with human mammary gland adenocarcinoma (MDA-MB-231) and macrophage (J774A.1) cell lines, exposed to concentrations of 12.5, 25, 50, or 100 µg/ml of either extract. For acute oral toxicity, comet assay and micronucleus (MN) tests, a single dose of 2,000 mg/kg of either extract was administered orally to Wistar rats. TLC analysis identified classes of metabolites in the extracts, including cinnamic acid derivatives, flavonoids, hydrolyzable tannins, condensed tannins, coumarins, and terpenes/steroids. In the cytotoxicity assay, the varying concentrations of extracts derived from embiratanha induced no significant alterations in the viability of MDA-MB-231 cells. The lowest concentration of EtEx significantly increased macrophage J774A.1 viability. However, the higher concentrations of AqEx markedly lowered macrophage J774A.1 viability. Animals exhibited no toxicity in the parameters analyzed in acute oral toxicity, comet assay, and MN tests. Further, EtEx promoted a significant reduction in DNA damage index and DNA damage frequency utilizing the comet assay, while the group treated with AqEx exhibited no marked differences. Thus, data demonstrated that AqEx or EtEx of embiratanha may be considered safe at a dose of 2,000 mg/kg orgally under our experimental conditions tested.

Sanguinarine: an alkaloid with promising in vitro and in vivo antiparasitic activity against different developmental stages of Schistosoma mansoni and in silico pharmacokinetic properties (ADMET).

The objective of the study was to evaluate the in vitro and in vivo schistosomicidal activity of sanguinarine (SA) on Schistosoma mansoni and its in silico pharmacokinetic parameters. ADMET parameters and oral bioavailability were evaluated using the PkCSM and SwissADME platforms, respectively. The activity of SA in vitro, at the concentrations of 1.0-25 µM, was analyzed through the parameters of motility, mortality, and cell viability of the worms at intervals of 3-24 h. Mice were infected with cercariae and treated by gavage with SA (5 mg/kg/day, in a single dose or two doses of 2.5 mg/kg every 12 h for 5 consecutive days) on the 1st (skin schistosomula), 14th (pulmonary schistosomula), 28th (young worms), and 45th (adult worms) days after infection. In vitro and in vivo praziquantel was the control. In vitro, SA showed schistosomicidal activity against schistosomula, young worms, and couples; with total mortality and reduced cell viability at low concentrations and incubation time. In a single dose of 5 mg/kg/day, SA reduces the total worm load by 47.6%, 54%, 55.2%, and 27.1%, and female worms at 52.0%, 39.1%, 52.7%, and 20.2%, respectively, results which are similar to the 2.5 mg/kg/day dose. SA reduced the load of eggs in the liver, and in histopathological and histomorphometric analyses, there was a reduction in the number and volume of hepatic granulomas, which exhibited less inflammatory infiltrate. SA has promising in vitro and in vivo schistosomicidal activity against different developmental stages of S. mansoni, in addition to reducing granulomatous liver lesions. Furthermore, in silico, SA showed good predictive pharmacokinetic ADMET profiles.

Assessment of Cytotoxic/Antitumour Potential and in silico Study of Salazinic Acid Isolated from Parmotrema concurrens.

INTRODUCTION: Despite numerous scientific advances, cancer continues to be one of the main causes of death in the world. This situation has driven the search for promising molecules. Lichen substances have been widely described for their pharmacological potential. OBJECTIVE: The present study evaluated the antitumour potential of a depsidone isolated from Parmotrema concurrens- salazinic acid (SAL) - through in vitro, in vivo and in silico studies. METHODS: The molecule was isolated from the acetonic extract of the lichen and recrystallized in acetone. The macrophage J774, sarcoma-180 and MDA-MB-231 cell lines were used for the MTT cytotoxicity assay. The antitumor assay used a murine model (Swiss albino mice) with sarcoma-180. The animals were treated for seven consecutive days with doses of SAL (25 and 50 mg/kg) and 5-fluorouracil (20 mg/kg). RESULTS: Its purity was determined using high-performance liquid chromatography (94%), and its structure was confirmed by H1 and C13 nuclear magnetic resonance. SAL was not considered toxic to cancer cell lines, showing cell viability rates of 79.49 ± 4.15% and 86.88 ± 1.02% for sarcoma-180 and MDA-MB-231, respectively. The tumour inhibition rate was greater than 80% in the animals treated with SAL and 65% for those that received 5-fluorouracil. Simulations of molecular dynamics to estimate the flexibility of the interactions between human thymidylate synthase and derivatives of SAL and 5-fluorouracil revealed that SAL exhibited greater enzymatic interaction capacity, with highly favourable energy, compared to 5-fluorouracil. CONCLUSION: The present results demonstrate the potential of salazinic acid as a tumour inhibition agent.

Evaluation of the cytotoxicity, oral toxicity, genotoxicity, and mutagenicity of the latex extracted from Himatanthus drasticus (Mart.) Plumel (Apocynaceae).

ETHNOPHARMACOLOGICAL RELEVANCE: Himatanthus drasticus is a tree popularly known as janaguba. Endemic to Brazil, it is found in the Cerrado and Caatinga biomes, rock fields, and rainforests. Janaguba latex has been used in folk medicine for its antineoplastic, anti-inflammatory, analgesic, and antiallergic activities. However, studies investigating the safety of its use for medicinal purposes are limited. AIM OF THE STUDY: This study aimed to evaluate the toxicity of the latex extracted from H. drasticus. MATERIALS AND METHODS: The latex was extracted from H. drasticus specimens by removing a small area of bark (5 × 30 cm) and then dissolving the exudate in water and lyophilizing it. Phytochemical screening was performed by TLC and GC-MS, protein, and carbohydrate levels. Cell viability was performed by the MTT method. Acute oral toxicity, genotoxicity, and mutagenicity assays were performed in mice. RESULTS: TLC showed the presence of saponins and reducing sugars, as well as steroids and terpenes. The GC-MS analysis of the nonpolar fraction identified lupeol acetate, betulin, and α/ß-amyrin derivatives as the major compounds. The latex was toxic to S-180 cells at 50 and 100 µg/mL. No signals of toxicity or mutagenicity was found in mice treated with 2000 mg/kg of the latex, but genotoxicity was observed in the Comet assay. CONCLUSIONS: H. drasticus latex showed toxicity signals at high doses (2000 mg/kg). Although the latex was not mutagenic to mice, it was genotoxic in the Comet assay in our experimental conditions. Even testing a limit dose of 2000 mg/kg, which is between 10 to 35-fold the amount used in folk medicine, caution must be taken since there is no safe level for genotoxic compounds exposure. Further studies on the toxicological aspects of H. drasticus latex are necessary to elucidate its possible mechanisms of genotoxicity.

Effect of acute exposure in swiss mice (Mus musculus) to a fibrinolytic protease produced by Mucor subtilissimus UCP 1262: An histomorphometric, genotoxic and cytological approach.

The fibrinolytic enzyme produced by Mucor subtilissimus UCP 1262 was obtained by solid fermentation and purified by ion exchange chromatography using DEAE-Sephadex A50. The enzyme toxicity was evaluated using mammalian cell lineages: HEK-293, J774.A1, Sarcoma-180 and PBMCs which appeared to be viable at a level of 80%. The biochemical parameters of the mice treated with an acute dose of enzyme (2000 mg/mL) identified alterations of AST and ALT and the histomorphometric analysis of the liver showed a loss of endothelial cells (P < 0.001). However, these changes are considered minimal to affirm that there was a significant degree of hepatotoxicity. The comet assay and the micronucleus test did not identify damage in the DNA of the erythrocytes of the animals treated. The protease did not degrade the Aα and Bß chains of human and bovine fibrinogens, thus indicating that it does not act as anticoagulant, but rather as a fibrinolytic agent. The assay performed to assess blood biocompatibility shows that at dose of 0.3-5 mg/mL the hemolytic grade is considered insignificant. Moreover, the enzyme did not prolong bleeding time in mice when dosed with 1 mg/kg. These results indicate that this enzyme produced is a potential competitor for developing novel antithrombotic drugs.

Nanoencapsulation of usnic acid: An attempt to improve antitumour activity and reduce hepatotoxicity.

Despite the recognised antiproliferative and antitumour properties of usnic acid, its therapeutic application has yet to be introduced. In fact, the high hepatotoxicity and low water solubility of usnic acid have somewhat restricted its practical use in anticancer therapy. The aim of this study was therefore to investigate the antitumour activity of usnic acid encapsulated into nanocapsules prepared with lactic co-glycolic acid polymer. Usnic acid-loaded nanocapsules were obtained using the interfacial deposition of a preformed polymer. The antitumour activity was confirmed on an ascitic tumour (Sarcoma-180) implanted in Swiss mice and estimated by means of the tumour inhibition. The results of antitumour activity confirmed that the encapsulation of usnic acid into PLGA-nanocapsules produced a 26.4% increase in tumour inhibition as compared with the standard free usnic acid treatment. Vacuolization of hepatocytes and a mild lymphocytic infiltration in portal spaces were observed in animals treated with free usnic acid. However, this hepatotoxicity was substantially reduced when animals were treated with usnic acid-loaded nanocapsules. No histological changes were noticed in the kidneys or spleen of animals treated either with usnic acid or usnic acid-loaded nanocapsules. These results suggest that nanoencapsulation may be a way of enabling usnic acid to be used in chemotherapy.