RESUMO

Cancer is an increasingly common disease and is considered one of the main causes of death in the world. Lophocereus schottii (L. schottii) is a cactus used in Mexico in traditional medicine for cancer treatment. This study aimed to determine the effect of the ethanolic extract and the polar and nonpolar fractions of L. schottii in murine L5178Y lymphoma cells in vitro, analyzing their effect on the proliferative activity of splenocytes, and establishing the effective concentration 50 (EC50) of the polar fraction. In addition, the secondary metabolites present in the extracts were determined by ultra-performance liquid chromatography-mass spectrometry (UPLC-MS). The study establishes that the three extracts of L. schottii have a cytotoxic effect on L5178Y cells and on the splenocytes stimulated with ConA. Additionally, the polar fraction has a significantly greater effect being three times more effective than cyclophosphamide on inhibiting the viability of L5178Y cells. Secondary metabolites present are mainly flavonoids and alkaloids, but there are also some terpenoids and sterols. Ultimately, polar fraction can be considered an anticancer substance, since its EC50 of 15 µg/mL is within the parameters established by the National Cancer Institute.

RESUMO

BACKGROUND: In the therapy of cancer, several treatments have been designed using nanomaterials, among which gold nanoparticles (AuNPs) have been featured as a promising antitumoral agent. Our research group has developed the synthesis of gold nanoparticles L-AuNPs and D-AuNPs stabilized with zwitterions of imidazolium (L-1 and D-1) derived from L-methionine and D-methionine. Because the stabilizer agent is chiral, we observed through circular dichroism that AuNPs also present chirality; such chirality as well as the fact that the stabilizing agent contains fragments of methionine and imidazolium that are commonly involved in biological processes, opens up the possibility that this system may have biological compatibility. Additionally, the presence of methionine in the stabilizing agent opens the application of this system as a possible antitumor agent because methionine is involved in methylation processes of molecules such as DNA. OBJECTIVE: The aim of this research is the evaluation of the antitumor activity of gold nanoparticles stabilized with zwitterions of imidazolium (L-AuNPs) derived from L-methionine in the model of BALB/c mice with lymphoma L5178Y. METHODS: Taking as a parameter cell density, the evaluation of the inhibitory effect of L-AuNPs was carried out with a series of in vivo tests in BALB/c type mice; three groups of five mice each were formed (Groups 1, 2 and 3); all mice were i.p. inoculated with the lymphoblast murine L5178Y. Group 1 consisted of mice without treatment. In the Groups 2 and 3 the mice were treated with L-AuNPs at 0.3 mg/Kg on days 1, 7 and 14 by orally and intraperitonally respectively. RESULTS: These results show low antitumor activity of these gold nanoparticles (L-NPsAu) but interestingly, the imidazolium stabilizing agent of gold nanoparticle (L-1) displayed promising antitumor activity. On the other hand, the enantiomer of L-1, (D-1) as well as asymmetric imidazole derivate from L-methionine (L-2), do not exhibit the same activity as L-1. CONCLUSION: The imidazolium stabilizing agent (L-1) displayed promising antitumor activity. Modifications in the structure of L-1 showed that, the stereochemistry (like D-1) and the presence of methionine fragments (like L-2) are determinants in the antitumor activity of this compound.

Assuntos

RESUMO

We studied in vivo antitumor effect of epimastigote form detritus of Trypanosoma cruzi, Mexican Albarrada strain, on L5178Y malignant tumor in BALB/c mice. The antitumor effect of ultrasonic detritus of the parasite was confirmed by shrinkage of the tumor and changed size of its symplastic necroses.

Assuntos

RESUMO

Epidemiological studies link increased garlic consumption with a reduced incidence of cancer in various human populations. Experimental carcinogenesis studies in animal models and in cell culture systems indicate that several allium-derived compounds exhibit inhibitory effects. To provide a better understanding of the effects of allium derivatives on the prevention of cancer, we examined allicin, the major component of garlic, for their effects on antitumoral activity in vitro and in L5178Y lymphoma bearing mice. We found that allicin decreased the growth of tumor cells whereas in vivo, the compound shown an antitumor effect in murine L5178Y lymphoma. Allicin enhanced the secretion of IL-2, IFN-gamma and TNF-alpha cytokines from mouse plasma. These cytokines are associated with the beneficial Th1 antitumor response, which is characteristic of effective cancer immunotherapies.

Los estudios epidemiológicos relacionan el aumento del consumo de ajo con una disminución en la incidencia de cáncer en diferentes poblaciones humanas. Los estudios experimentales de carcinogénesis en modelos animales y en los cultivos de células tumorales indican que varios compuestos derivados del ajo tienen efectos inhibitorios. A fin de proporcionar una mejor comprensión de los efectos de derivados del ajo en la prevención del cáncer, se evaluó la alicina el principal componente del ajo, en la actividad antitumoral in vitro y en ratones con linfoma. Se encontró que la alicina disminuyó el crecimiento de células tumorales, mientras que in vivo, el compuesto muestra un efecto antitumoral en el linfoma murino L5178Y. La alicina incrementó la secreción de las citocinas IL-2, interferón-gamma y TNF-alfa obtenidas de plasma de ratón con linfoma. Estas citocinas están asociadas con la respuesta antitumoral benéfica Th1, que es característica de inmunoterapias efectivas para el cáncer.

Assuntos