An aqueous extract of Vitex agnus castus alters the labeling of blood constituents with technetium-99m

The development of experimental assays to study properties of herbal medicine is worthwhile. Vitex agnus castus (VAC) is utilized in popular medicine and some actions have been attributed to its extract. Blood cells (BC) and plasma proteins are labeled with technetium-99m (Tc-99m) and have been used in nuclear medicine, as in basic research. This procedure uses a reducing agent and stannous ion is utilized. There are reports that drugs can alter this labeling process. The aim of this work was to evaluate the influence of an aqueous extract of VAC on the labeling of blood constituents with Tc-99m. Blood was incubated with VAC, stannous chloride and Tc-99m, as sodium pertechnetate, and centrifuged. Samples of BC and plasma were separated, aliquots of BC and plasma were also precipitated with trichloroacetic acid to obtain soluble and insoluble fractions and the percentage of radioactivity ( percentATI) was determined. The results show a statistical (p<0.05) alteration in the percentATI on blood compartments and on the insoluble fractions of plasma and BC. Probably, this extract would have chemical compounds with oxidant properties.

Modelos experimentais são relevantes no estudo de propriedades de plantas medicinais. Vitex agnus castus (VAC) é usado na medicina popular. Células sanguíneas (CS) e proteínas plasmáticas são marcadas com tecnécio-99m (Tc-99m) com aplicações na medicina nuclear e em pesquisa. Esse procedimento utiliza um agente redutor e o íon estanoso é usado. Drogas podem alterar esse processo de marcação. O objetivo desse trabalho foi avaliar a influência de um extrato aquoso de VAC na marcação de constituintes sanguíneos com Tc-99m. Sangue foi incubado com VAC, cloreto estanoso e Tc-99m, como pertecnetato de sódio e centrifugado. Amostras de CS e plasma foram separadas, alíquotas de CS e plasma foram também precipitadas com ácido tricloroacético para obtenção de frações solúvel (FS) e insolúvel (FI) e a percentagem de radioatividade ( por centoATI) foi determinada. Os resultados mostraram uma alteração estatística (p<0.05) na por centoATI dos compartimentos sanguíneos e nas FI do plasma e CS. Provavelmente, esse extrato poderia ter compostos químicos com propriedades oxidantes.

An aqueous extract of Pfaffia sp. does not alter the labeling of blood constituents with technetium-99m and the morphology of the red blood cells

Plants have been used for the human beings as food, as additives and/or as medicines. There are controversies about the biological effects of several natural products and, it is worthwhile to try to develop experimental assays to evaluate properties of extracts of plants. Pfaffia sp. is utilized in popular medicine and various properties have been attributed to its extract. Red blood cells (RBC) and plasma proteins are labeled with technetium-99m (Tc-99m) and this labeling procedure depends on a reducing agent and stannous ion is usually used. There are reports that drugs can alter the labeling of blood elements with Tc-99m. We have evaluated the influence of a Pfaffia sp. extract on the labeling of blood constituents with Tc-99m and on the morphology of RBC. Blood was incubated with an aqueous extract of Pfaffia sp., stannous chloride and Tc-99m. Samples were centrifuged and plasma and blood cells were separated and also precipitated with trichloroacetic acid. Soluble and insoluble fractions were separated. The results did not show alteration in the uptake of radioactivity and no modifications on the shape of the RBC in presence of Pfaffia sp. Once this labeling process depends on a reducing agent, probably, this extract has compounds with anti-oxidant properties as already described elsewhere, that could protect the stannous ions against the oxidation process. This fact would aid the labeling process of blood elements with Tc-99m.