Uncaria tomentosa extract: evaluation of effects on the in vitro and in vivo labeling of blood constituents with technetium-99m

The influence (in vivo and in vitro) of an Uncaria tomentosa extract (Cats claw) on the labeling of red blood cells (RBCs) and plasma and cellular proteins with technetium-99m (Tc-99m) was evaluated. For the in vivo treatment, animals were treated with Cats claw. For the in vitro treatment, heparinized blood was incubated with Cats claw before the addition of stannous chloride (SnCl2) and Tc-99m. Samples of plasma (P) and RBCs were separated and also precipitated with trichloroacetic acid. The soluble and insoluble fractions of P and RBCs were isolated. The analysis of the results of the in vivo study, indicates that there is no significant alteration on the uptake of Tc-99m by the blood constituents, but it significantly decrease (p<0.05) the labeling of blood constituents by in vitro methods. These effects could be due to chelation of stannous and /or pertechnetate ions and blockage of the Tc-99m bindings sites

Experimental models using radionuclides for assessment of the effects of natural drugs

The aim of this study was to evaluate the effect of the extracts of Nectandra membranacea (N. membranacea), Ginkgo biloba (EGb) and Passiflora (PEF) on the morphology of red blood cells (RBC), on the biodistribution of sodium pertechnetate (99mTcO4Na), on the morphology of duodenum and on the labeling of blood constituents (BC, IF-P, IF-BC) with technetium-99m (Tc-99m). Morphometry studies also were performed. The results show that EGb promotes alteration of the labeling of BC, IF-P and IF-BC (p<0.05). The N. membranacea extract does not promote significant alteration of the radiolabeling, and PEF extract alters the IF-P labeling. N. membranacea, EGb and PEF extracts were able to alter the RBC morphology (P<0.05). N. membranacea extract and EGb modifies the biodistribution of the 99mTcO4Na, and EGb influences the morphometry of duodenum isolated from rats (P<0.05)

Effect of an Arctium lappa (burdock) extract on the labeling of blood constituents with technetium-99m and on the morphology of the red blood cells

Arctium lappa (burdock) has been used to treat inflammatory processes. Blood constituents labeled with technetium-99m (99mTc) have been utilized in nuclear medicine. It was evaluated the influence of a burdock extract on the labeling of blood constituents with 99mTc and on the morphometry of red blood cells. Blood samples from Wistar rats were incubated with burdock extract and the radiolabeling procedure was carried out. Plasma and blood cells, soluble and insoluble fractions of plasma and blood cells were separated. The radioactivity in each fraction was counted and the percentages of radioactivity (%ATI) were determined. Morphology and morphometric (perimeter/area ratio) measurements of red blood cells (RBC) were performed. The incubation with burdock extract significantly (p<0.05) altered the %ATI on the blood compartments and the perimeter/area ratio of RBC, as well as, induced modifications on the shape of RBC. Alterations on membrane could justify the decrease of labeling of blood cells with 99mTc obtained in this study

The ingestión of a Nectandra membranácea extract changes the bioavailability of technetium-99m radiobiocomplex in rat organs

The radiobiocomplexes labeled with technetium-99m (Tc-99m) have been widely used in nuclear medicine in single photon emission computed tomography and in basic research. The aim of this study was to assess the influence of a Nectandra membranácea extract on the bioavailability of the sodium pertechnetate (Na99mTc0(4)) radiobiocomplex in rat organs. The animals were treated with a N. membranácea extract (30 mg/ ml), for 6 days. Na99mTc0(4) was injected, the organs were isolated and weighed, and the radioactivity was determined in each organ (%ATI/organ). The %ATI/organ was divided by the mass of each organ to calculate the %ATI/g. A significant increase of the %ATI/organ of Na99mTc0(4) was observed in muscle and thyroid as well as in the %ATI/g in the heart, kidney and thyroid. These findings could result from the interaction between components of the plant extract and the radiobiocomplex which may influence the uptake Na99mTc0(4) in rat organs. Therefore, precaution is suggested in the interpretation of nuclear medicine results in patients using this her

Uncaria tomentosa extract: evaluation of effects on the in vitro and in vivo labeling of blood constituents with technetium-99m

The influence (in vivo and in vitro) of an Uncaria tomentosa extract (Cats claw) on the labeling of red blood cells (RBCs) and plasma and cellular proteins with technetium-99m (Tc-99m) was evaluated. For the in vivo treatment, animals were treated with Cats claw. For the in vitro treatment, heparinized blood was incubated with Cats claw before the addition of stannous chloride (SnCl2) and Tc-99m. Samples of plasma (P) and RBCs were separated and also precipitated with trichloroacetic acid. The soluble and insoluble fractions of P and RBCs were isolated. The analysis of the results of the in vivo study, indicates that there is no significant alteration on the uptake of Tc-99m by the blood constituents, but it significantly decrease (p<0.05) the labeling of blood constituents by in vitro methods. These effects could be due to chelation of stannous and /or pertechnetate ions and blockage of the Tc-99m bindings sites.<br>O objetivo do presente estudo foi avaliar a influência (in vivo e in vitro) de um extrato de Uncaria tomentosa (unha de gato) na marcação de hemácias e proteínas plasmáticas e celulares com tecnécio-99m (Tc-99m). Para o estudo in vivo, animais foram tratados com um extrato de unha de gato. Para o estudo in vitro, sangue heparinizado foi incubado com o extrato de unha de gato antes da adição de cloreto estanoso (SnCl2) e Tc-99m. Amostras de plasma e células foram separadas e também precipitadas com ácido tricloracético. As frações solúveis e insolúveis foram isoladas. A análise dos resultados do estudo in vivo, indica que não houve alteração significante na captação de Tc-99m pelos constituintes sanguíneos, entretanto, no tratamento in vitro, ocorreu redução significante da marcação de constituintes sanguíneos. Esses efeitos poderiam ser justificados por quelação dos íons estanoso e pertecnetato e bloqueio dos sítios de ligação do Tc-99m

Bioavailability of the sodium pertechnetate and morphometry of organs isolated from rats: study of possible pharmacokinetic interactions of a ginkgo biloba extract

Many compounds affect the bioavailability of radiobiocomplexes as radiopharmaceuticals. Ginkgo Biloba extract (EGb) has several effects. The influence of an EGb on the bioavailability of the radiobiocomplex sodium pertechnetate (Na99mTcO4) and on the morphometry of the organs was evaluated. Rats were treated with EGb and Na99mTcO4 was injected. The animals were sacrificed; the radioactivity in the organs was counted. The results showed that EGb altered the Na99mTcO4 bioavailability in the kidneys, liver and duodenum. Morphometric analysis of the organs showed significant alterations (P<0.05), probably caused by metabolites generated by EGb and capable of altering the bioavailability of the Na99mTcO4.<br>Substâncias podem interferir na biodisponibilidade de radiobiocomplexos, como os radiofármacos. O extrato de Ginkgo Biloba (EGb) apresenta efeitos. Avaliou-se a influência de um EGb na biodisponibilidade do pertecnetato de sódio (99mTcO-4Na) e na morfometria de órgãos de ratos que foram tratados com EGb. 99mTcO-4Na foi injetado, os animais sacrificados e a radioatividade nos órgãos contada. Os resultados mostraram que o EGb alterou a biodisponibilidade do 99mTcO-4Na em rins, fígado e duodeno e alterações morfométricas significativas (p<0.05) foram encontradas. Sugere-se que o EGb poderia gerar metabólitos capazes de alterar morfometricamente os órgãos citados e alterar a biodisponibilidade do 99mTcO-4Na