Antitumor effect of laticifer proteins of Himatanthus drasticus (Mart.) Plumel - Apocynaceae.

ETHNOPHARMACOLOGICAL RELEVANCE: Himatanthus drasticus (Mart.) Plumel - Apocynaceae is a medicinal plant popularly known as Janaguba. Its bark and latex have been used by the public for cancer treatment, among other medicinal uses. However, there is almost no scientific research report on its medicinal properties. AIM OF THE STUDY: The aim of this study was to investigate the antitumor effects of Himatanthus drasticus latex proteins (HdLP) in experimental models. MATERIALS AND METHODS: The in vitro cytotoxic activity of the HdLP was determined on cultured tumor cells. HdLP was also tested for its ability to induce lysis of mouse erythrocytes. In vivo antitumor activity was assessed in two experimental models, Sarcoma 180 and Walker 256 carcinosarcoma. Additionally, its effects on the immunological system were also investigated. RESULTS: HdLP did not show any significant in vitro cytotoxic effect at experimental exposure levels. When intraperitoneally administered, HdLP was active against both in vivo experimental tumors. However, it was inactive by oral administration. The histopathological analysis indicates that the liver and kidney were only weakly affected by HdLP treatment. It was also demonstrated that HdLP acts as an immunomodulatory agent, increasing the production of OVA-specific antibodies. Additionally, it increased relative spleen weight and the incidence of megakaryocyte colonies. CONCLUSION: In summary, HdLP has some interesting anticancer activity that could be associated with its immunostimulating properties.

Avaliação do controle radioquímico do Ricinus communis L. e Tc-99m na marcação de hemácias / Assessment of the radiochemical control of Ricinus communis L. and Tc-99m with the labeling of red blood cells

O Ricinus communis L. pertence à família das Euforbiáceas, possui frutos típicos de onde é extraído o óleo de rícino, altamente tóxico. Neste estudo foi analisado o efeito do extrato de Ricinus communis L na marcação de hemácias com Tc-99m através do controle radioquímico. Os resultados mostraram que no controle radioquímico por meio da cromatografia, foi observado que o extrato marcado com Tc-99m mostrou duas frações com 130.007 e 494.592 cpm, e na marcação de hemácias, com por centoATI de 61.88 e 41.32 por cento nas frações 1 e 2. Foi concluído que o extrato de R. communis L. altera a captação do Tc-99m in vitro, competindo com o material radioativo em possíveis sítios de ligação nas células vermelhas do sangue, como a capacidade de oxidação do íon estanoso ou por competição com o íon pertecnetato.

Ricinus communis L. belongs to the Euphorbiaceae family, from whose fruits the ricin oil is extracted, highly toxic. In this study it was analyzed the effect of the extract of Ricinus communis L. in the labeling of red blood cells with Tc-99m through the radiochemical control. The results showed that in the radiochemical control through chromatography, it was observed that the extract labeled with Tc-99m showed two fractions with 130.007 and 494.592 cpm, and in the labeling of red blood cells, with percentATI of 61.88 and 41.32 percent in the fractions 1 and 2. It has been concluded that the extract of Ricinus communis alters the captivating of Tc-99m in vitro, competing with the radioactive material in the possible binding sites of the red blood cells, as well in the capacity of oxidation of the stannous ion or by competition with the pertechnetate ion.