Biochemical and pharmacokinetic characterisation of two PEGylated variants of dipetarudin

2009 ◽  
Vol 102 (09) ◽  
pp. 454-459 ◽  
Author(s):  
Anne Koehler ◽  
Goetz Nowak ◽  
Mercedes López
Keyword(s):  
Gel Filtration ◽  
Pharmacokinetic Profile ◽  
Peripheral Compartment ◽  
Therapeutic Application ◽  
Similar Activity ◽  
Elimination Half ◽  
K 12 ◽  
Extravascular Compartment

SummaryDipetarudin was coupled to polyethylene glycol (PEG)-5000 residues in order to improve its pharmacokinetic profile and to enhance its anticoagulant efficacy. The resulting compounds, mono-and di-PEGylated dipetarudin were purified by gel filtration. Mono-PEGylated dipetarudin exhibited similar activity like its non-conjugated equivalent both in vitro and in vivo. However, di-PEGylated dipetarudin showed longer distribution and elimination half-lives and higher area under the time-concentration curve in comparison with the unmodified inhibitor which may be attributed to decreased renal clearance. Futhermore, ratio k 12/k 21 decreased when the number of PEG chains coupled to dipetarudin increased. It means that the intercompartment transfer of dipetarudin, characterised by a fast distribution and a high retention in the peripheral compartment, is reverted by coupling to PEG. Thus, the transfer of mono-PEGylated dipetarudin between these compartments is similar in both senses and the transfer of di-PEGylated dipetarudin is slower from vascular to extravascular compartment than vice versa. Our results show that di-PEGylated dipetarudin produces a better and longer anticoagulant effect than unmodified dipetarudin which is a desirable attribute for future therapeutic application.

Abstract P371: Fusion Of C-type Natriuretic Peptide With Elastin-like Polypeptide For Enhanced Pharmacological Activity

2021 ◽  
Vol 129 (Suppl_1) ◽  
Author(s):  
James D Jowett ◽  
Susan Arnold ◽  
Bret Umsted ◽  
Dave Sendecki ◽  
Dave Dickerhoff ◽  
...  
Keyword(s):  
Natriuretic Peptide ◽  
Slow Release ◽  
Therapeutic Potential ◽  
Pharmacokinetic Profile ◽  
Temperature Dependent ◽  
E Coli ◽  
Elimination Half ◽  
Long Acting

C-type natriuretic peptide (CNP) is a pluripotent molecule produced by the endothelium and myocardium with therapeutic potential in pulmonary hypertension, myocardial infarction, and heart failure. However, the native peptide’s short elimination half-life of under 3 minutes limits its use clinically. To improve the pharmacokinetic profile of CNP we recombinantly expressed the CNP peptide as a fusion with an elastin-like polypeptide (ELP). ELPs are biopolymers that undergo reversible temperature-dependent phase separation and form a subcutaneous depot upon injection. CNP-ELP fusion proteins were expressed in E. coli , purified, and showed in vitro potency 2-4 fold less than native CNP. When administered subcutaneously in mice CNP-ELP showed a significantly enhanced PK profile due to the slow release of the fusion into the circulation with detectable fusion protein 24 hours after a single injection. In addition, the CNP-ELP increased growth velocity in mice significantly greater than that of native peptide indicating an in vivo activation of the CNP receptor, NPR-B. These findings represent a new method of administering a long acting CNP peptide for treatment of different cardiovascular diseases.

Purification of the Antihemophilic Factor by Gel Filtration on Agarose

1969 ◽  
Vol 22 (03) ◽  
pp. 577-583 ◽  
Author(s):  
M.M.P Paulssen ◽  
A.C.M.G.B Wouterlood ◽  
H.L.M.A Scheffers
Keyword(s):  
Factor Viii ◽  
Plasma Proteins ◽  
Large Scale ◽  
Gel Filtration ◽  
Large Scale Preparation ◽  
Scale Preparation ◽  
Antihemophilic Factor

SummaryFactor VIII can be isolated from plasma proteins, including fibrinogen by chromatography on agarose. The best results were obtained with Sepharose 6B. Large scale preparation is also possible when cryoprecipitate is separated by chromatography. In most fractions containing factor VIII a turbidity is observed which may be due to the presence of chylomicrons.The purified factor VIII was active in vivo as well as in vitro.

Half-Life of Platelet Factor 4 (PF-4) in Plasma and Platelets from Macaca Mulatta

1977 ◽  
Vol 37 (01) ◽  
pp. 073-080 ◽  
Author(s):  
Knut Gjesdal ◽  
Duncan S. Pepper
Keyword(s):  
Macaca Mulatta ◽  
Half Life ◽  
Human Platelet ◽  
Gel Filtration ◽  
Platelet Factor 4 ◽  
Active Protein ◽  
Platelet Factor ◽  
Membrane Bound

SummaryHuman platelet factor 4 (PF-4) showed a reaction of complete identity with PF-4 from Macaca mulatta when tested against rabbit anti-human-PF-4. Such immunoglobulin was used for quantitative precipitation of in vivo labelled PF-4 in monkey serum. The results suggest that the active protein had an intra-platelet half-life of about 21 hours. In vitro 125I-labelled human PF-4 was injected intravenously into two monkeys and isolated by immuno-precipita-tion from platelet-poor plasma and from platelets disrupted after gel-filtration. Plasma PF-4 was found to have a half-life of 7 to 11 hours. Some of the labelled PF-4 was associated with platelets and this fraction had a rapid initial disappearance rate and a subsequent half-life close to that of plasma PF-4. The results are compatible with the hypothesis that granular PF-4 belongs to a separate compartment, whereas membrane-bound PF-4 and plasma PF-4 may interchange.

Significance of In-Vitro and In-Vivo Correlation in Drug Delivery System

2018 ◽  
Vol 4 (4) ◽  
pp. 523-531
Author(s):  
Hina Mumtaz ◽  
Muhammad Asim Farooq ◽  
Zainab Batool ◽  
Anam Ahsan ◽  
Ashikujaman Syed
Keyword(s):  
Dosage Form ◽  
Pharmaceutical Preparations ◽  
Pharmacokinetic Profile ◽  
In Vitro Dissolution ◽  
Time Saving ◽  
Pharmaceutical Dosage Form ◽  
Short Period ◽  
Form Development

The main purpose of development pharmaceutical dosage form is to find out the in vivo and in vitro behavior of dosage form. This challenge is overcome by implementation of in-vivo and in-vitro correlation. Application of this technique is economical and time saving in dosage form development. It shortens the period of development dosage form as well as improves product quality. IVIVC reduce the experimental study on human because IVIVC involves the in vivo relevant media utilization in vitro specifications. The key goal of IVIVC is to serve as alternate for in vivo bioavailability studies and serve as justification for bio waivers. IVIVC follows the specifications and relevant quality control parameters that lead to improvement in pharmaceutical dosage form development in short period of time. Recently in-vivo in-vitro correlation (IVIVC) has found application to predict the pharmacokinetic behaviour of pharmaceutical preparations. It has emerged as a reliable tool to find the mode of absorption of several dosage forms. It is used to correlate the in-vitro dissolution with in vivo pharmacokinetic profile. IVIVC made use to predict the bioavailability of the drug of particular dosage form. IVIVC is satisfactory for the therapeutic release profile specifications of the formulation. IVIVC model has capability to predict plasma drug concentration from in vitro dissolution media.

Design, Synthesis, and Pharmacokinetic Evaluation of O-Carbamoyl Tizoxanide Prodrugs

2020 ◽  
Vol 16 ◽  
Author(s):  
Xi He ◽  
Wenjun Hu ◽  
Fanhua Meng ◽  
Xingzhou Li
Keyword(s):  
Plasma Concentration ◽  
Broad Spectrum ◽  
Plasma Concentrations ◽  
Antiviral Drug ◽  
Systemic Exposure ◽  
Pharmacokinetic Profile ◽  
Hydroxyl Group ◽  
First Pass

Background: The broad-spectrum antiparasitic drug nitazoxanide (N) has been repositioned as a broad-spectrum antiviral drug. Nitazoxanide’s in vivo antiviral activities are mainly attributed to its metabolitetizoxanide, the deacetylation product of nitazoxanide. In reference to the pharmacokinetic profile of nitazoxanide, we proposed the hypotheses that the low plasma concentrations and the low system exposure of tizoxanide after dosing with nitazoxanide result from significant first pass effects in the liver. It was thought that this may be due to the unstable acyloxy bond of nitazoxanide. Objective: Tizoxanide prodrugs, with the more stable formamyl substituent attached to the hydroxyl group rather than the acetyl group of nitazoxanide, were designed with the thought that they might be more stable in plasma. It was anticipated that these prodrugs might be less affected by the first pass effect, which would improve plasma concentrations and system exposure of tizoxanide. Method: These O-carbamoyl tizoxanide prodrugs were synthesized and evaluated in a mouse model for pharmacokinetic (PK) properties and in an in vitro model for plasma stabilities. Results: The results indicated that the plasma concentration and the systemic exposure of tizoxanide (T) after oral administration of O-carbamoyl tizoxanide prodrugs were much greater than that produced by equimolar dosage of nitazoxanide. It was also found that the plasma concentration and the systemic exposure of tizoxanide glucuronide (TG) were much lower than that produced by nitazoxanide. Conclusion: Further analysis showed that the suitable plasma stability of O-carbamoyl tizoxanide prodrugs is the key factor in maximizing the plasma concentration and the systemic exposure of the active ingredient tizoxanide.

scholarly journals AZP2006, a new promising treatment for Alzheimer’s and related diseases

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
N. Callizot ◽  
C. Estrella ◽  
S. Burlet ◽  
A. Henriques ◽  
C. Brantis ◽  
...  
Keyword(s):  
Therapeutic Application ◽  
Neuroprotective Effects ◽  
Beneficial Effects ◽  
Potential Therapeutic Application ◽  
Promising Treatment ◽  
Central Synapses ◽  
First Time ◽  
Pgrn Level

AbstractProgranulin (PGRN) is a protein with multiple functions including the regulation of neuroinflammation, neuronal survival, neurite and synapsis growth. Although the mechanisms of action of PGRN are currently unknown, its potential therapeutic application in treating neurodegenerative diseases is huge. Thus, strategies to increase PGRN levels in patients could provide an effective treatment. In the present study, we investigated the effects of AZP2006, a lysotropic molecule now in phase 2a clinical trial in Progressive Supranuclear Palsy patients, for its ability to increase PGRN level and promote neuroprotection. We showed for the first time the in vitro and in vivo neuroprotective effects of AZP2006 in neurons injured with Aβ1–42 and in two different pathological animal models of Alzheimer’s disease (AD) and aging. Thus, the chronic treatment with AZP2006 was shown to reduce the loss of central synapses and neurons but also to dramatically decrease the massive neuroinflammation associated with the animal pathology. A deeper investigation showed that the beneficial effects of AZP2006 were associated with PGRN production. Also, AZP2006 binds to PSAP (the cofactor of PGRN) and inhibits TLR9 receptors normally responsible for proinflammation when activated. Altogether, these results showed the high potential of AZP2006 as a new putative treatment for AD and related diseases.

scholarly journals Unraveling the In Vivo Protein Corona

Cells ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 132
Author(s):  
Johanna Simon ◽  
Gabor Kuhn ◽  
Michael Fichter ◽  
Stephan Gehring ◽  
Katharina Landfester ◽  
...  
Keyword(s):  
Plasma Proteins ◽  
Ex Vivo ◽  
Protein Corona ◽  
Blood Proteins ◽  
Therapeutic Application ◽  
Complex Situation ◽  
Ex Vivo Approach ◽  
In Vivo Administration

Understanding the behavior of nanoparticles upon contact with a physiological environment is of urgent need in order to improve their properties for a successful therapeutic application. Most commonly, the interaction of nanoparticles with plasma proteins are studied under in vitro conditions. However, this has been shown to not reflect the complex situation after in vivo administration. Therefore, here we focused on the investigation of magnetic nanoparticles with blood proteins under in vivo conditions. Importantly, we observed a radically different proteome in vivo in comparison to the in vitro situation underlining the significance of in vivo protein corona studies. Next to this, we found that the in vivo corona profile does not significantly change over time. To mimic the in vivo situation, we established an approach, which we termed “ex vivo” as it uses whole blood freshly prepared from an animal. Overall, we present a comprehensive analysis focusing on the interaction between nanoparticles and blood proteins under in vivo conditions and how to mimic this situation with our ex vivo approach. This knowledge is needed to characterize the true biological identity of nanoparticles.

Age-dependent changes in volume and haemoglobin content of erythrocytes in the carp (Cyprinus carpio L.)

1989 ◽  
Vol 141 (1) ◽  
pp. 133-149 ◽  
Author(s):  
W. Speckner ◽  
J. F. Schindler ◽  
C. Albers
Keyword(s):  
Gel Filtration ◽  
Linear Increase ◽  
Human Erythrocytes ◽  
Main Peak ◽  
Red Cell ◽  
Human Haemoglobin ◽  
Cell Fractions ◽  
Haemoglobin Content

Carp erythrocytes were fractionated by angle-head centrifugation which yielded fractions with a linear increase in density. Haematological examinations revealed that the heavier red blood cells of carp had greater volumes (MCV), more haemoglobin (MCH) and higher haemoglobin concentrations (MCHC) than light ones. The same experiments with human red cell fractions yielded a decrease in MCV, constant MCH and an increase in MCHC. Haemoglobin content in individual erythrocytes was also determined by scanning stage absorbance cytophotometry to establish the frequency distribution of the cellular haemoglobin contents. In carp, the distribution was symmetrical with the means increasing with density. No such change with cell density was found in human erythrocytes. Both carp and human erythrocytes incorporated [2-14C]glycine in vitro. After gel filtration, radioactivity was detected in carp, but not in human, haemoglobin fractions. 14C was found in all three haemoglobin fractions, obtained by isoelectric focusing, and was present in the haem and in the globin. [2-14C]glycine-labelled erythrocytes were reinjected into chronically cannulated carp and followed in vivo for several months. With time, the main peak of scintillation counts shifted from red cell fractions of low to high density. This is considered as evidence that density and age of red cells in carp are positively correlated and that erythrocytes can synthesize haemoglobin while circulating in the peripheral blood.

HEMODIALYSIS OF THE RAT

1966 ◽  
Vol 44 (5) ◽  
pp. 849-859 ◽  
Author(s):  
Sumner M. Robinson ◽  
David A. Hurwitz ◽  
Robert Louis-Ferdinand ◽  
William F. Blatt
Keyword(s):  
Molecular Weight ◽  
Gel Filtration ◽  
Low Molecular Weight

A technique is described for hemodialysis of either anesthetized or non-restrained rats. In the apparatus the dialysis plates of an autoanalyzer system are used with only minor modification. The efficiency of this method has been evaluated with regard to the clearance of saccharides, both in vitro and in vivo, as well as the extraction of nitrogenous low molecular weight moieties from circulating blood. Approximately 50% of the dialyzable material was obtained in a 1-hour dialysis. Further fractionation of the dialyzate was accomplished by gel filtration (Sephadex G-25).

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