Oxygen is the key factor associated with the difference between in vivo and in vitro effects of antioxidants

SummaryThe authors previously reported a transient decrease in adhesive platelet count and an enhancement of blood coagulability after administration of a small amount of adrenaline (0.1-1 µg per Kg, i. v.) in man and rabbit. In such circumstances, the sensitivity of platelets to aggregation induced by ADP was studied by an optical density method. Five minutes after i. v. injection of 1 µg per Kg of adrenaline in 10 rabbits, intensity of platelet aggregation increased to 115.1 ± 4.9% (mean ± S. E.) by 10∼5 molar, 121.8 ± 7.8% by 3 × 10-6 molar and 129.4 ± 12.8% of the value before the injection by 10”6 molar ADP. The difference was statistically significant (P<0.01-0.05). The above change was not observed in each group of rabbits injected with saline, 1 µg per Kg of 1-noradrenaline or 0.1 and 10 µg per Kg of adrenaline. Also, it was prevented by oral administration of 10 mg per Kg of phenoxybenzamine or propranolol or aspirin or pyridinolcarbamate 3 hours before the challenge. On the other hand, the enhancement of ADP-induced platelet aggregation was not observed in vitro, when 10-5 or 3 × 10-6 molar and 129.4 ± 12.8% of the value before 10∼6 molar ADP was added to citrated platelet rich plasma (CPRP) of rabbit after incubation at 37°C for 30 second with 0.01, 0.1, 1, 10 or 100 µg per ml of adrenaline or noradrenaline. These results suggest an important interaction between endothelial surface and platelets in connection with the enhancement of ADP-induced platelet aggregation by adrenaline in vivo.

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Comparison of Specific Antibody, D-Phe-Pro-Arg-CH2Cl and Aprotinin for Prevention of In Vitro Effects of Recombinant Tissue-Type Plasminogen Activator on Haemostasis Parameters

Thrombosis and Haemostasis ◽

10.1055/s-0038-1646016 ◽

1987 ◽

Vol 58 (03) ◽

pp. 921-926 ◽

Cited By ~ 21

Author(s):

E Seifried ◽

P Tanswell

Keyword(s):

Specific Antibody ◽

Plasma Concentrations ◽

Fibrinolytic Therapy ◽

Tissue Type ◽

Control Value ◽

Type Plasminogen Activator ◽

In Vitro Effects ◽

Fibrinolytic Parameters

SummaryIn vitro, concentration-dependent effects of rt-PA on a range of coagulation and fibrinolytic assays in thawed plasma samples were investigated. In absence of a fibrinolytic inhibitor, 2 μg rt-PA/ml blood (3.4 μg/ml plasma) caused prolongation of clotting time assays and decreases of plasminogen (to 44% of the control value), fibrinogen (to 27%), α2-antiplasmin (to 5%), FV (to 67%), FVIII (to 41%) and FXIII (to 16%).Of three inhibitors tested, a specific polyclonal anti-rt-PA antibody prevented interferences in all fibrinolytic and most clotting assays. D-Phe-Pro-Arg-CH2Cl (PPACK) enabled correct assays of fibrinogen and fibrinolytic parameters but interfered with coagulometric assays dependent on endogenous thrombin generation. Aprotinin was suitable only for a restricted range of both assay types.Most in vitro effects were observed only with rt-PA plasma concentrations in excess of therapeutic values. Nevertheless it is concluded that for clinical application, collection of blood samples on either specific antibody or PPACK is essential for a correct assessment of in vivo effects of rt-PA on the haemostatic system in patients undergoing fibrinolytic therapy.

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Reliability of a Single β-Thromboglobulin Measurement in a Diabetic Population : Importance of PGE1 in Anticoagulant Mixture

Thrombosis and Haemostasis ◽

10.1055/s-0038-1651094 ◽

1987 ◽

Vol 57 (02) ◽

pp. 201-204 ◽

Cited By ~ 2

Author(s):

P Y Scarabin ◽

L Strain ◽

C A Ludlam ◽

J Jones ◽

E M Kohner

Keyword(s):

In Vitro Release ◽

Mean Value ◽

Reliable Estimate ◽

Diabetic Patients ◽

Single Measurement ◽

Diabetic Population ◽

The Difference ◽

Vitro Release

SummaryDuring the collection of samples for plasma β-thromboglobulin (β-TG) determination, it is well established that artificially high values can be observed due to in-vitro release. To estimate the reliability of a single β-TG measurement, blood samples were collected simultaneously from both arms on two separate occasions in 56 diabetic patients selected for a clinical trial. From each arm, blood was taken into two tubes containing an anticoagulant mixture with (tube A) and without (tube B) PGE!. The overall mean value of B-TG in tube B was 1.14 times higher than in tube A (p <0.01). The markedly large between-arms variation accounted for the most part of within-subject variation in both tubes and was significantly greater in tube B than in tube A. Based on the difference between B-TG values from both arms, the number of subjects with artifically high B-TG values was significantly higher in tube B than in tube A on each occasion (overall rate: 28% and 14% respectively). Estimate of between-occasions variation showed that B-TG levels were relatively stable for each subject between two occasions in each tube. It is concluded that the use of PGEi decreases falsely high B-TG levels, but a single measurement of B-TG does not provide a reliable estimate of the true B-TG value in vivo.

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Nanodrugs as a new approach in therapy of cardiovascular diseases and cancer with tumor-associated angiogenesis

Current Medicinal Chemistry ◽

10.2174/0929867328666201231121704 ◽

2020 ◽

Vol 28 ◽

Author(s):

Justyna Hajtuch ◽

Karolina Niska ◽

Iwona Inkielewicz-Stepniak

Keyword(s):

Cardiovascular Disease ◽

Cardiovascular Diseases ◽

Controlled Drug Release ◽

Biological Properties ◽

Comprehensive Information ◽

Conventional Drug ◽

Key Factor ◽

Functionalized Materials

Background: Cancer along with cardiovascular diseases are globally defined as leading causes of death. Importantly, some risk factors are common to these diseases. The process of angiogenesis and platelets aggregation are observed in cancer development and progression. In recent years, studies have been conducted on nanodrugs in these diseases that have provided important information on the biological and physicochemical properties of nanoparticles. Their attractive features are that they are made of biocompatible, well-characterized and easily functionalized materials. Unlike conventional drug delivery, sustained and controlled drug release can be obtained by using nanomaterials. Methods: In this article, we review the latest research to provide comprehensive information on nanoparticle-based drugs for the treatment of cancer, cardiovascular disease associated with abnormal haemostasis, and the inhibition of tumorassociated angiogenesis. Results: The results of the analysis of data based on nanoparticles with drugs confirm their improved pharmaceutical and biological properties, which gives promising antiplatelet, anticoagulant and antiangiogenic effects. Moreover, the review included in vitro, in vivo research and presented nanodrugs with chemotherapeutics approved by Food and Drug Administration. Conclusion: By the optimization of nanoparticles size and surface properties, nanotechnology are able to deliver drugs with enhanced bioavailability in treatment of cardiovascular disease, cancer and inhibition of cancer-related angiogenesis. Thus, nanotechnology can improve the therapeutic efficacy of the drug, but there is a need for a better understanding of the nanodrugs interaction in the human body, because this is a key factor in the success of potential nanotherapeutics.

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In Vitro Effects of Sulforaphane on Interferon-Driven Inflammation and Exploratory Evaluation in Two Healthy Volunteers

Molecules ◽

10.3390/molecules26123602 ◽

2021 ◽

Vol 26 (12) ◽

pp. 3602

Author(s):

Elena Genova ◽

Maura Apollonio ◽

Giuliana Decorti ◽

Alessandra Tesser ◽

Alberto Tommasini ◽

...

Keyword(s):

Healthy Volunteers ◽

Supportive Therapy ◽

P Value ◽

Type I ◽

Interferon Signature ◽

Interferon Stimulated Genes ◽

Immune System Activation ◽

In Vitro Effects

Interferonopathies are rare genetic conditions defined by systemic inflammatory episodes caused by innate immune system activation in the absence of pathogens. Currently, no targeted drugs are authorized for clinical use in these diseases. In this work, we studied the contribution of sulforaphane (SFN), a cruciferous-derived bioactive molecule, in the modulation of interferon-driven inflammation in an immortalized human hepatocytes (IHH) line and in two healthy volunteers, focusing on STING, a key-component player in interferon pathway, interferon signature modulation, and GSTM1 expression and genotype, which contributes to SFN metabolism and excretion. In vitro, SFN exposure reduced STING expression as well as interferon signature in the presence of the pro-inflammatory stimulus cGAMP (cGAMP 3 h vs. SFN+cGAMP 3 h p value < 0.0001; cGAMP 6 h vs. SFN+cGAMP 6 h p < 0.001, one way ANOVA), restoring STING expression to the level of unstimulated cells. In preliminary experiments on healthy volunteers, no appreciable variations in interferon signature were identified after SFN assumption, while only in one of them, presenting the GSTM1 wild type genotype related to reduced SFN excretion, could a downregulation of STING be recorded. This study confirmed that SFN inhibits STING-mediated inflammation and interferon-stimulated genes expression in vitro. However, only a trend towards the downregulation of STING could be reproduced in vivo. Results obtained have to be confirmed in a larger group of healthy individuals and in patients with type I interferonopathies to define if the assumption of SFN could be useful as supportive therapy.

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A Detailed Examination of the in vivo and in vitro Effects of ACTH on Gonadotropin Secretion in the Adult Rat

Neuroendocrinology ◽

10.1159/000124090 ◽

1985 ◽

Vol 40 (4) ◽

pp. 297-302 ◽

Cited By ~ 18

Author(s):

David R. Mann ◽

Diane Evans ◽

Festus Edoimioya ◽

Freja Kamel ◽

George M. Butterstein

Keyword(s):

Detailed Examination ◽

Gonadotropin Secretion ◽

Adult Rat ◽

In Vitro Effects

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Contamination of erythropoietin by endotoxin: in vivo and in vitro effects on murine erythropoiesis

Blood ◽

10.1182/blood.v54.1.146.146 ◽

1979 ◽

Vol 54 (1) ◽

pp. 146-158 ◽

Cited By ~ 8

Author(s):

KS Zuckerman ◽

PJ Quesenberry ◽

J Levin ◽

R Sullivan

Keyword(s):

Significant Inhibition ◽

Erythropoietic Activity ◽

Limulus Amebocyte Lysate ◽

Endogenous Erythropoietin ◽

Significant Change ◽

In Vitro Effects ◽

Stimulation Of

Abstract Endotoxin was detected in all erythropoietin preparations tested and was removed from four lots, without loss of erythropoietic activity, by adsorption with limulus amebocyte lysate. Comparison of adsorbed (endotoxin-depleted) and nonadsorbed (endotoxin-containing) erythropoietin preparations demonstrated significant inhibition of CFU- e and BFU-e in vitro by nonadsorbed erythropoietin at concentrations higher than 0.25 U/ml and 2.0 U/ml, respectively. CFU-e and BFU-e were inhibited significantly by readdition in vitro of 10(-5)-10(-3) mug of endotoxin per unit of limulus-adsorbed erythropoietin. Administration of saline or 6 U of nonadsorbed or adsorbed erythropoietin twice a day for 4 days of CF1 mice resulted in reticulocyte counts of 2.1%, 9.9%, and 15.9%, respectively. Nonadsorbed erythropoietin resulted in a 29% decrease in erythropoiesis, a 42% decrease in CFU-e, and a 16% increase in granulopoiesis in the marrow, whereas adsorbed erythropoietin caused a 28% increase in erythropoiesis, no significant change in CFU-e and a 19% decrease in granulopoiesis in the marrow. Both preparations resulted in marked increases in splenic erythropoiesis and granulopoiesis. The effects of adsorbed erythropoietin are similar to those produced following stimulation of hematopoiesis by endogenous erythropoietin. Hemopoietic changes induced by nonadsorbed erythropoietin in vivo and in vitro are affected substantially by contamination of the erythropoietin preparations with endotoxin.

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