Copaifera spp. oleoresins and two isolated compounds (ent-kaurenoic and ent-polyalthic acid) inhibit Toxoplasma gondii growth in vitro

Toxoplasmosis affects about one-third of the world's population. The disease treatment methods pose several side effects and do not efficiently eliminate the parasite, making the search for new therapeutic approaches necessary. We aimed to assess the anti-Toxoplasma gondii activity of four Copaifera oleoresins (ORs) and two isolated diterpene acids, named ent-kaurenoic and ent-polyalthic acid. We used HeLa cells as an experimental model of toxoplasmosis. Uninfected and infected HeLa cells were submitted to the treatments, and the parasite intracellular proliferation, cytokine levels and ROS production were measured. Also, tachyzoites were pre-treated and the parasite invasion was determined. Finally, an in silico analysis was performed to identify potential parasite targets. Our data show that the non-cytotoxic concentrations of ORs and diterpene acids controlled the invasion and proliferation of T. gondii in HeLa cells, thus highlighting the possible direct action on parasites. In addition, some compounds tested controlled parasite proliferation in an irreversible manner. An additional and non-exclusive mechanism of action involves the modulation of host cell components, by affecting the upregulation of the IL-6. Additionally, molecular docking suggested that ent-polyalthic acid has a high affinity for the active site of the TgCDPK1 protein. Copaifera ORs have great antiparasitic activity against T. gondii, and this effect can be partially explained by the presence of the isolated compounds ent-kaurenoic and ent-polyalthic acid.

Conventional and PEGylated Liposomes as Vehicles of Copaifera sabulicola

Traditional medicine uses resin oils extracted from plants of the genus Copaifera for several purposes. Resin oils are being studied to understand and profile their pharmacological properties. The aim of this work was to prepare and to characterize conventional and pegylated liposomes incorporating resin oils or the hexanic extract obtained from Copaifera sabulicola (copaiba) leaves. The cytotoxic effect of these products was also investigated. Conventional and stealth liposomes with copaiba extract showed similar average diameters (around 126 nm), encapsulation efficiencies greater than 75% and were stable for 90 days. A cytotoxicity test was performed on murine glioma cells and the developed liposomes presented antiproliferative action against these cancer cells at the average concentration of 30 μg/mL. Phytochemicals encapsulated in PEGylated liposomes induced greater reduction in the viability of tumor cells. In addition, bioassay-s measured the cytotoxicity of copaiba resin oil (Copaifera sabulicola) in liposomes (conventional and PEGylated), which was also checked against pheochromocytoma PC12 cells. Its safety was verified in normal rat astrocytes. The results indicate that liposomes encapsulating copaiba oil showed cytotoxic activity against the studied tumor strains in a dose-dependent fashion, demonstrating their potential applications as a chemotherapeutic bioactive formulation.

Investigation of Copaifera genus as a new source of antimycobaterial agents

AIM

This paper reports on the antimycobacterial activity of the oleoresins and extracts obtained from Copaifera spp.

MATERIALS & METHODS

The minimum inhibitory concentration (MIC) and fractional inhibitory concentration index techniques helped to evaluate the effect of these oleoresins and extracts against six strains of mycobacteria that cause tuberculosis.

RESULTS & CONCLUSION

Among the assayed oleoresins and plant extracts, the Copaifera langsdorffii, Copaifera duckei, Copaifera reticulata and Copaifera trapezifolia oleoresins provided the lowest MIC values against some of the tested strains. The combination of Copaifera spp. samples with isoniazid did not evidence any synergistic action. Some Copaifera spp. oleoresins may represent a future source for the discovery of new antimycobacterial drugs due to their low MIC values.

Assessment of genotoxic activity of oleoresins and leaves extracts of six Copaifera species for prediction of potential human risks

ETHNOPHARMACOLOGICAL RELEVANCE

Copaifera species are used in folk medicine for a wide variety of pharmacological properties. This paper reports the cytotoxic and genotoxic analyses of oleoresins and leaves extracts of Copaifera species: C. duckei, C. multijuga, C. paupera, C. pubiflora, C. reticulata and C. trapezifolia.

MATERIALS AND METHODS

In vitro assays were performed using Chinese hamster lung fibroblasts (V79 cells). The clonogenic efficiency and cytokinesis-block micronucleus assays were employed for the cytotoxicity and genotoxicity assessment, respectively. The mouse bone marrow micronucleus test was used for in vivo studies.

RESULTS

The cytotoxicity results using the clonogenic efficiency assay showed IC₅₀ values ranging from 9.8 to 99.2 µg/mL for oleoresins and 66.4-721.5 for leaves extracts. However, no cytotoxic effect was observed in the in vivo studies. Additionally, the treatments with oleoresins and leaves extracts did not significantly increase the frequency of micronuclei in both in vitro and in vivo mammalian cells. The UPLC-MS/MS and CG/MS analyses of Copaifera oleoresins allowed the identification of 10 acid diterpenes and 11 major volatile sesquiterpenes. Leaves are rich in phenolic compounds including two flavonoid heterosides and 16 galloylquinic acid derivatives.

CONCLUSIONS

The oleoresins and leaves extracts of studied Copaifera species were not cytotoxic in vivo, as well as not genotoxic in both in vitro and vivo assays, under the experimental conditions used. Therefore, the obtained results should be sufficient to demonstrate the absence of significant genotoxic risk of these Copaifera products for human use in the evaluated concentrations range.