Assessment of the effect of Bacopa monnieri (L.) Wettst. extract on the labeling of blood elements with technetium-99m and on the morphology of red blood cells

Abstract

RESUMO: "Avaliação do efeito do extrato de Bacopa monnieri (L.) Wettst. na marcação de elementos sanguíneos com tecnécio-99m e na morfologia de células vermelhas do sangue." Bacopa monnieri (L.) Wettst. (BM), uma planta tradicional da medicina ayurvédica, é usada por séculos para problemas de memória, antiinflamatória, antitérmica, sedativa e como agente anti-epiléptico. O extrato BM têm sido extensivamente investigada por diversos autores por seus efeitos neurofarmacológicas. Na medicina nuclear, os glóbulos vermelhos (RBC) marcados com tecnécio-99m (99mTc) tem várias aplicações clínicas. Entretanto, os dados demonstraram que drogas sintéticas ou naturais podem modificar a marcação de hemácias com 99mTc. Como Bacopa monnieri é amplamente utilizado em medicina, foi avaliada a sua influência na marcação de hemácias e proteínas plasmáticas com tecnécio-99m (99mTc). Este procedimento de marcação depende de um agente redutor e normalmente o cloreto estanoso é usado. Sangue foi incubado com os extratos BM. Solução de cloreto estanoso e 99mTc foram adicionados. O sangue foi centrifugado e o plasma (P) e células sangüíneas (CS) foram isolados. Amostras de P ou BC também foram precipitadas, centrifugadas e fração insolúvel (FI) e fração solúvel (FS) foram separadas. A porcentagem de radioatividade (%ATI) em BC, IF-BC e SE-P foram calculados. A As% ATI diminuiu significativamente em BC de 95,53±0,45-35,41±0,44, no IF-P de 80,20±1,16 para 7,40±0,69 e no IF-BC em 73,31±1,76-21,26±1,40. O estudo da morfologia de hemácias revelou alterações morfológicas importantes devido a tratamentos com extratos BM. Sugere-se que a ação do extrato BM poderia ser explicada por uma inibição dos íons estanoso e pertecnetato ou oxidação do íon estanoso ou por danos na membrana plasmática.Unitermos: Bacopa monnieri, Scrophulariaceae, tecnécio-99m, células sanguíneas vermelhas, plasma, proteinas, morphologia.ABSTRACT: Bacopa monnieri (L.) Wettst. (BM), a traditional Ayurvedic medicine, used for centuries as a memory enhancing, anti-inflammatory, antipyretic, sedative and antiepileptic agent. BM extract have been extensively investigated by several authors for their neuropharmacological effects. In nuclear medicine, red blood cells (RBC) labeled with technetium-99m (99mTc) have several clinical applications. However, data have demonstrated that synthetic or natural drugs could modify the labeling of RBC with 99mTc. As Bacopa monnieri is extensively used in medicine, we evaluated its influence on the labeling of RBC and plasma proteins using technetium-99m (99mTc). This labeling procedure depends on a reducing agent and usually stannous chloride is used. Blood was incubated with BM extracts. Stannous chloride solution and 99mTc were added. Blood was centrifuged and plasma (P) and blood cells (BC) were isolated. Samples of P or BC were also precipitated, centrifuged and insoluble fraction (IF) and soluble fraction (SF) were separated. The percentage of radioactivity (%ATI) in BC, IF-BC and IF-P were calculated. The %ATI significantly decreased on ...

Evaluation of biologic effects of an Ilex paraguariensis aqueous extract on the labeling of blood constituents with technetium-99m and on the morphology of red blood cells

“…Data have demonstrated the effects of synthetic and natural drugs on this radiolabeling process (Mousinho et al, 2008;Holanda et al, 2009;Bustani et al, 2009;Rocha et al, 2009;De et al, 2009;Cekic et al, 2011;Souza et al, 2011). In consequence, the labeling of blood constituents with 99m Tc has been used as an in vitro assay to screening effects of synthetic or natural products that could have actions related to the band-3 and calcium channels or antioxidant/oxidant properties.…”

“…In consequence, the labeling of blood constituents with 99m Tc has been used as an in vitro assay to screening effects of synthetic or natural products that could have actions related to the band-3 and calcium channels or antioxidant/oxidant properties. Moreover, qualitative and quantitative morphological analysis of RBC has been used as a method to evaluate if the effects of drugs on this radiolabeling process could be related to changes on shape of RBC (Rocha et al, 2009;De et al, 2009).…”

An aqueous extract of Liu Wei Di Huang Wan alters the labeling of blood constituents with Technetium-99m

“…Assays using radionuclides have been utilized successfully in various investigations related with extracts of medicinal formulas [15] or isolated medicinal plant [16].…”

“…Moreover, 99m Tc has been an important tool in various experimental models [16,[19][20][21][22][23][24][25]. Tc-Red blood cells (RBC) are used to get images of the cardiovascular system and, the spleen, on the detection and localisation of gastrointestinal hemorrhages and on the measurement of RBC [26][27][28].…”

“…To obtain 99m Tc-RBC, samples of blood have been treated with stannous chloride (SnCl 2 ), as reducing agent, and plasma and blood proteins have been also labeled [17,18,29]. In addition, an experimental model to study the properties of natural products has been developed using the labeling of blood constituents with 99m Tc [16,20,21,30]. Effects of synthetic or natural drugs on the labeling of blood constituents have been previously reported [20,24,25,31,32], and, they are often undesirable.…”