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.

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Acetylsalicylic acid and labeling of blood constituents with technetium-99m

Brazilian Archives of Biology and Technology ◽

10.1590/s1516-89132005000700024 ◽

2005 ◽

Vol 48 (spe2) ◽

pp. 163-168 ◽

Cited By ~ 3

Author(s):

Adenilson de Souza da Fonseca ◽

Jacques Natan Grinapel Frydman ◽

Vanessa Câmara da Rocha ◽

Mario Bernardo-Filho

Keyword(s):

Acetylsalicylic Acid ◽

Whole Blood ◽

Wistar Rats ◽

Human Beings ◽

Blood Constituents ◽

Technetium 99M ◽

In Vivo Assays ◽

99Mtc Labeling

Acetylsalicylic acid is the drug most used an anti-inflammatory agent and for secondary prevention of thrombotic phenomenon. Drugs can modify the labeling of blood constituents with technetium-99m (99mTc). The aim of this work was to evaluate the effect of in vitro or in vivo assays with acetylsalicylic acid on the labeling of the blood constituents with 99mTc. In vitro assay was performed with samples of whole blood from Wistar rats incubated with acetylsalicylic acid (1.0 mg/ml) for one hour before the 99mTc-labeling process. For in vivo assay, Wistar rats were treated with acetylsalicylic acid (1.5 mg/kg) during one hour, and the whole blood was withdrawn for the 99mTc-labeling process. Saline was used in control groups. Data showed that the fixation of 99mTc to the blood constituents was not significantly (p>0.05) modified in in vitro and in vivo assays with acetylsalicylic acid, at least not when the experiments were carried out with the doses normally used in human beings.

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Analysis of antidepressant properties of some Papaver species by in vivo and in vitro methods

Planta Medica ◽

10.1055/s-0035-1565761 ◽

2015 ◽

Vol 81 (16) ◽

Cited By ~ 2

Author(s):

OML Bayazeid ◽

F Yalcin ◽

M İlhan ◽

H Karahan ◽

E Kupeli-Akkol ◽

...

Keyword(s):

In Vitro Methods

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The Effects of Some Synthetic Compounds on In Vitro Fibrinolytic Activity Measured by Different Methods and the Relevance to Activity In Vivo

Thrombosis and Haemostasis ◽

10.1055/s-0038-1649018 ◽

1972 ◽

Vol 28 (03) ◽

pp. 351-358

Author(s):

A.J Baillie ◽

A. K Sim

Keyword(s):

Inhibitory Activity ◽

Substrate Concentration ◽

Fibrinolytic Activity ◽

Synthetic Compounds ◽

In Vitro Methods ◽

Narrow Concentration Range

SummaryThe activity of several synthetic compounds, rated from good to poor (or inactive) fibrinolytic activators, has been assessed by two different commonly-used in vitro methods. Compounds shown to be active over a narrow concentration range in the hanging clot test were shown to be inhibitors of plasmin and trypsin in the casein-olytic test. The inhibitory activity of these compounds was shown to increase with increasing substrate concentration and apparent activity in the hanging clot test. Possible explanations and relevance of these observations are discussed.

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In Vitro Toxicology Methods in Risk Assessment

Alternatives to Laboratory Animals ◽

10.1177/026119299602400305 ◽

1996 ◽

Vol 24 (3) ◽

pp. 325-331

Author(s):

Iain F. H. Purchase

Keyword(s):

Risk Assessment ◽

Hazard Assessment ◽

Human Health Risk ◽

In Vitro Test ◽

In Vitro Methods ◽

New Concepts ◽

Vitro Test

The title of this paper is challenging, because the question of how in vitro methods and results contribute to human health risk assessment is rarely considered. The process of risk assessment usually begins with hazard assessment, which provides a description of the inherent toxicological properties of the chemical. The next step is to assess the relevance of this to humans, i.e. the human hazard assessment. Finally, information on exposure is examined, and risk can then be assessed. In vitro methods have a limited, but important, role to play in risk assessment. The results can be used for classification and labelling; these are methods of controlling exposure, analogous to risk assessment, but without considering exposure. The Ames Salmonella test is the only in vitro method which is incorporated into regulations and used widely. Data from this test can, at best, lead to classification of a chemical with regard to genotoxicity, but cannot be used for classification and labelling on their own. Several in vitro test systems which assess the topical irritancy and corrosivity of chemicals have been reasonably well validated, and the results from these tests can be used for classification. The future development of in vitro methods is likely to be slow, as it depends on the development of new concepts and ideas. The in vivo methods which currently have reasonably developed in vitro alternatives will be the easiest to replace. The remaining in vivo methods, which provide toxicological information from repeated chronic dosing, with varied endpoints and by mechanisms which are not understood, will be more difficult to replace.

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Studies of Metabolism Mediated Mutagenicity In Vitro

Alternatives to Laboratory Animals ◽

10.1177/026119299001800124.1 ◽

1990 ◽

Vol 18 (1_part_1) ◽

pp. 243-250

Author(s):

Dag Jenssen ◽

Lennart Romert

Keyword(s):

Cell Lines ◽

Biological Effects ◽

Animal Experiments ◽

Culture Technique ◽

Organ Perfusion ◽

Isolated Cells ◽

Toxicological Effect ◽

In Vitro Methods

To understand the cause of the biological effects of xenobiotic metabolism in mammals, investigators have traditionally performed animal experiments by comparing the results of biochemical methods, such as measurement of enzyme activity analysis of the metabolites produced, with the observed toxicological effect. This article deals with in vitro methods for genotoxicity combined with drug metabolising preparations at the organelle, cell or organ levels, as exemplified by microsome preparations, isolated cells/cell lines and organ perfusion systems, respectively. The advantage of some of these methods for studying metabolism-mediated mutagenicity is that the measured endpoint reflects not only the bioactivating phase I reactions, but also the detoxifying phase II reactions, and the transfer of the non-conjugated reactive metabolites to other cells and their ability to cause mutations in these cells. In vivo, all these events are important factors in the initiation of cancer. A mechanistic advantage of the methods for metabolism-mediated mutagenicity in vitro is that the relevance of the different steps in metabolism for the mutational events can seldom be investigated in an in vivo assay. Furthermore, human studies can easily be performed using the co-culture technique with isolated human cells or cell lines.

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Treatment with Uncaria tomentosa Promotes Apoptosis in B16-BL6 Mouse Melanoma Cells and Inhibits the Growth of B16-BL6 Tumours

Molecules ◽

10.3390/molecules26041066 ◽

2021 ◽

Vol 26 (4) ◽

pp. 1066

Author(s):

Ali Zari ◽

Hajer Alfarteesh ◽

Carly Buckner ◽

Robert Lafrenie

Keyword(s):

Tumour Size ◽

Melanoma Cells ◽

Tunel Staining ◽

Aqueous Extracts ◽

Ki 67 ◽

Uncaria Tomentosa ◽

Mouse Melanoma ◽

Anti Cancer

Uncaria tomentosa is a medicinal plant native to Peru that has been traditionally used in the treatment of various inflammatory disorders. In this study, the effectiveness of U. tomentosa as an anti-cancer agent was assessed using the growth and survival of B16-BL6 mouse melanoma cells. B16-BL6 cell cultures treated with both ethanol and phosphate-buffered saline (PBS) extracts of U. tomentosa displayed up to 80% lower levels of growth and increased apoptosis compared to vehicle controls. Treatment with ethanolic extracts of Uncaria tomentosa were much more effective than treatment with aqueous extracts. U. tomentosa was also shown to inhibit B16-BL6 cell growth in C57/bl mice in vivo. Mice injected with both the ethanolic and aqueous extracts of U. tomentosa showed a 59 ± 13% decrease in B16-BL6 tumour weight and a 40 ± 9% decrease in tumour size. Histochemical analysis of the B16-BL6 tumours showed a strong reduction in the Ki-67 cell proliferation marker in U. tomentosa-treated mice and a small, but insignificant increase in terminal transferase dUTP nick labelling (TUNEL) staining. Furthermore, U. tomentosa extracts reduced angiogenic markers and reduced the infiltration of T cells into the tumours. Collectively, the results in this study concluded that U. tomentosa has potent anti-cancer activity that significantly inhibited cancer cells in vitro and in vivo.

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Prostaglandin F2α Represses IGF-I-Stimulated IRS1/Phosphatidylinositol-3-Kinase/AKT Signaling in the Corpus Luteum: Role of ERK and P70 Ribosomal S6 Kinase

Molecular Endocrinology ◽

10.1210/me.2009-0312 ◽

2010 ◽

Vol 24 (3) ◽

pp. 632-643 ◽

Cited By ~ 30

Author(s):

Edward Arvisais ◽

Xiaoying Hou ◽

Todd A. Wyatt ◽

Koumei Shirasuna ◽

Heinrich Bollwein ◽

...

Keyword(s):

Corpus Luteum ◽

Prostaglandin F2α ◽

Serine Phosphorylation ◽

Phosphatidylinositol 3 Kinase ◽

Akt Activation ◽

Diminished Capacity ◽

Igf I ◽

In Vitro Treatment

Abstract Little is known about the early intracellular events that contribute to corpus luteum regression. Experiments were designed to determine the effects of prostaglandin F2α (PGF2α) on phosphatidylinositol-3-kinase (PI3K)/Akt signaling in the corpus luteum in vivo and in vitro. Treatment of midluteal-phase cows with a luteolytic dose of PGF2α resulted in a rapid increase in ERK and mammalian target of rapamycin (mTOR)/p70 ribosomal protein S6 kinase (p70S6K1) signaling and a rapid suppression of Akt phosphorylation in luteal tissue. In vitro treatment of primary cultures of luteal cells with PGF2α also resulted in an increase in ERK and mTOR/p70S6K1 signaling and a diminished capacity of IGF-I to stimulate PI3K, Akt, and protein kinase C ζ activation. Accounting for the reductions in PI3K and Akt activation observed in response to PGF2α treatment, we found that PGF2α promoted the phosphorylation of serine residues (307, 612, 636) in the insulin receptor substrate 1 (IRS1) peptide sequence in vivo and in vitro. Serine phosphorylation of IRS1 was associated with reduced formation of IGF-I-stimulated IRS1/PI3Kp85 complexes. Furthermore, treatment with inhibitors of the MAPK kinase 1/ERK or mTOR/p70S6K1 signaling pathways prevented PGF2α-induced serine phosphorylation of IRS1 and abrogated the inhibitory actions of PGF2α on Akt activation. Taken together, these experiments provide compelling evidence that PGF2α treatment stimulates IRS1 serine phosphorylation, which may contribute to a diminished capacity to respond to IGF-I. It seems likely that the rapid changes in phosphorylation events are among the early events that mediate PGF2α-induced corpus luteum regression.

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