Toxicological and chemoprevention studies of Brazilian brown propolis from Araucaria sp.

Brazilian brown propolis (BBP) is a natural product derived predominantly from the south region of Brazil, where Araucaria forests are dominant. Despite its potential as a source of bioactive compounds with leishmanicidal, anti-inflammatory, nociceptive, and antimicrobial properties, BBP has not been comprehensively studied compared to green propolis. Therefore, this study aimed to determine the safety and chemopreventive potential of BBP. The cytotoxicity attributed to BBP was assessed using two different assays, while the Salmonella/microsome assay was employed to evaluate mutagenicity. The acute toxicity attributed to BBP was determined using a zebrafish model, while the chemopreventive potential was investigated utilizing Chinese hamster lung (V79) cell lines. Data demonstrated that BBP exerted cytotoxic effects at concentrations greater than or equal to 10 µg/ml and did not exhibit mutagenicity in Salmonella typhimurium strains TA98 and TA100. However, at the highest concentration tested (4000 µg/plate), BBP induced a significant increase in revertant colonies in S. typhimurium TA102 strain. The LC50 equivalent to 8.83 mg/L was obtained in the acute toxicity evaluation in zebrafish. BBP also showed antigenotoxic effect by significantly reducing chromosomal damage induced by the mutagen doxorubicin in V79 cell cultures at a concentration of 2.5 µg/ml. Compared to Brazilian green and red propolis, BBP exhibited greater toxicity. On the other hand, at lower concentrations, BBP displayed chemopreventive potential, which may be associated with the antioxidant capacity of the extract. These findings contribute to a better understanding of the biological properties and potential applications of BBP in treating various diseases.

Antitumor Effect of Manool in a Murine Melanoma Model.

The manool diterpene, found in abundance in Salvia officinalis L., showed a selective cytotoxic effect against murine melanoma cells. Therefore, the present study aimed to evaluate the antitumor potential of manool in a murine melanoma model, administered by three routes: oral, subcutaneous, and intraperitoneal. In addition, the antimelanoma effect of manool (orally) combined with cisplatin (subcutaneous) was evaluated. The results obtained revealed that manool, administered by the three routes, was able to significantly decrease the mass and frequency of mitosis of the tumor tissue. The data obtained revealed that manool, at a dose of 20 mg/kg, was able to significantly decrease the tumor mass when administered by the three routes, with the percentages of reduction being equivalent to 62.4% (oral), 48.5% (intraperitoneal), and 38.8% (subcutaneous), without toxic effects. The treatment of manool plus cisplatin led to 86.7% reduction in tumor mass, higher than that observed in treatment with manool or cisplatin alone (50.7%), although signs of toxicity have been observed. The results also showed that treatments with manool (20 mg/kg orally) and/or cisplatin did not alter the activity of caspase 3 cleaved in tumor tissue. Therefore, manool revealed a promising antimelanoma effect, but without involvement of the caspase 3 cleaved pathway.

Topical formulations containing Copaifera duckei Dwyer oleoresin improve cutaneous wound healing.

OBJECTIVE: Evaluation of the healing and toxicological effects of Copaifera duckei Dwyer oleoresin (CDO). MATERIALS AND METHODS: Rodents with skin lesions were divided into nine groups, including daily treatments with 1, 3 and 10% CDO, collagenase, antibiotic ointment and control groups, for 14 days. RESULTS: Treatment with 10% CDO reduced skin edema and hyperplasia, demonstrating anti-inflammatory effect of the oil. Reduction in the wound area was observed, indicating the healing effect of CDO. Histopathological analysis showed increases in angiogenesis and re-epithelialization in animals treated with the highest concentration. On the other hand, no alterations in ulcerations, inflammatory infiltrate, hemorrhage, congestion, degeneration, percentage of collagen fibers, number of cells stained with anti-macrophage migration inhibitory factor, or density of area stained with anti-collagen I and III were found. Toxicogenetic analysis revealed no differences in micronucleus frequencies or in the ratio of polychromatic erythrocytes to total erythrocytes between treated and negative control, demonstrating the absence of genotoxicity and cytotoxicity, respectively. There was no difference in levels of liver enzymes among groups, indicating the absence of hepatotoxicity. CONCLUSION: Formulations of CDO exerted beneficial effects on the stages of cutaneous wound healing and are promising options for the treatment of wounds.