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International Journal of Biological... Sep 2023Heparin is the most common anticoagulant used in clinical practice but shows some downsides such as short half-life (for the high molecular weight heparin) and secondary...
Heparin is the most common anticoagulant used in clinical practice but shows some downsides such as short half-life (for the high molecular weight heparin) and secondary effects. On the other hand, its low molecular weight analogue cannot be neutralized with protamine, and therefore cannot be used in some treatments. To address these issues, we conjugated polyethylene glycol (PEG) to heparin reducing end (end-on) via oxime ligation and studied the interactions of the conjugate (Hep-b-PEG) with antithrombin III (AT) and protamine. Isothermal titration calorimetry showed that Hep-b-PEG maintains the affinity to AT. Dynamic light scattering demonstrated that the Hep-b-PEG formed colloidal stable nanocomplexes with protamine instead of large multi-molecular aggregates, associated with heparin side effects. The in vitro (human plasma) and in vivo experiments (Sprague Dawley rats) evidenced an extended half-life and higher anticoagulant activity of the conjugate when compared to unmodified heparin.
Topics: Animals; Rats; Humans; Heparin; Protamines; Rats, Sprague-Dawley; Anticoagulants
PubMed: 37499705
DOI: 10.1016/j.ijbiomac.2023.125957 -
Journal of Cardiothoracic Surgery Jul 2021Intraoperative graft assessment with tools like Transit Time Flow Measurement (TTFM) is imperative for quality control in coronary surgery. We investigated the variation...
BACKGROUND
Intraoperative graft assessment with tools like Transit Time Flow Measurement (TTFM) is imperative for quality control in coronary surgery. We investigated the variation of TTFM parameters before and after protamine administration to identify new benchmark parameters for graft quality assessment.
METHODS
The database of the REQUEST ("REgistry for QUality AssESsmenT with Ultrasound Imaging and TTFM in Cardiac Bypass Surgery") study was retrospectively reviewed. A per graft analysis was performed. Only single grafts (i.e., no sequential nor composite grafts) where both pre- and post-protamine TTFM values were recorded with an acoustical coupling index > 30% were included. Grafts with incomplete data and mixed grafts (arterio-venous) were excluded. A second analysis was performed including single grafts only in the same MAP range pre- and post- protamine administration.
RESULTS
After adjusting for MAP, we found a small increase in MGF (29 mL/min to 30 mL/min, p = 0.009) and decrease in PI (2.3 to 2.2, p < 0.001) were observed after the administration of protamine. These changes were especially notable for venous conduits and for CABG procedures performed on-pump.
CONCLUSION
The small changes in TTFM parameters observed before and after protamine administration seem to be clinically irrelevant, despite being statistically significant in aggregate. Our data do not support a need to perform TTFM measurements both before and after protamine administration. A single TTFM measurement taken either before or after protamine may suffice to achieve reliable data on each graft's performance. Depending on the specific clinical situation and intraoperative changes, more measurements may be informative.
TRIAL REGISTRATION
Clinical Trials Number: NCT02385344 , registered February 17th, 2015.
Topics: Adult; Aged; Aged, 80 and over; Blood Flow Velocity; Coronary Artery Bypass; Coronary Circulation; Female; Heparin Antagonists; Humans; Male; Middle Aged; Protamines; Registries; Retrospective Studies; Vascular Patency
PubMed: 34243799
DOI: 10.1186/s13019-021-01575-y -
Biology of Reproduction Nov 2021While an E3 ubiquitin ligase, RNF8, was initially reported to be required for histone-to-protamine exchange in spermiogenesis, we subsequently demonstrated that RNF8 is...
While an E3 ubiquitin ligase, RNF8, was initially reported to be required for histone-to-protamine exchange in spermiogenesis, we subsequently demonstrated that RNF8 is not involved in this process. Nevertheless, reflecting a lingering misunderstanding in the field, a growing number of studies have continued to postulate a requirement for RNF8 in the histone-to-protamine exchange. For example, a recent study claimed that a mouse PIWI protein, MIWI, controls RNF8-mediated histone-to-protamine exchange. Here, confirming our earlier conclusions, we show that RNF8 is required neither for the establishment of histone H4K16 acetylation, which is an initial step in histone removal during spermiogenesis, nor for the incorporation of two protamine proteins, PRM1 and PRM2. Thus, whereas RNF8 mediates ubiquitination of H2A on the sex chromosomes in meiosis, during the prior stage of spermatogenesis, our genetic evidence underscores that RNF8 is not involved in histone-to-protamine exchange.
Topics: Acetylation; Animals; Biological Transport; Chromatin Assembly and Disassembly; Histones; Mice; Mice, Knockout; Protamines; Sex Chromosomes; Spermatogenesis; Ubiquitin-Protein Ligases; Ubiquitination
PubMed: 34225362
DOI: 10.1093/biolre/ioab132 -
BMC Evolutionary Biology Jan 2016Protamines are sperm nuclear proteins with a crucial role in chromatin condensation. Their function is strongly linked to sperm head morphology and male fertility.... (Comparative Study)
Comparative Study
BACKGROUND
Protamines are sperm nuclear proteins with a crucial role in chromatin condensation. Their function is strongly linked to sperm head morphology and male fertility. Protamines appear to be affected by a complex pattern of selective constraints. Previous studies showed that sexual selection affects protamine coding sequence and expression in rodents. Here we analyze selective constraints and post-copulatory sexual selection acting on protamine 2 (Prm2) gene sequences of 53 species of primates and rodents. We focused on possible differences in selective constraints between these two clades and on the two functional domains of PRM2 (cleaved- and mature-PRM2). We also assessed if and how changes in Prm2 coding sequence may affect sperm head dimensions.
RESULTS
The domain of Prm2 that is cleaved off during binding to DNA (cleaved-Prm2) was found to be under purifying selection in both clades, whereas the domain that remains bound to DNA (mature-Prm2) was found to be positively selected in primates and under relaxed constraint in rodents. Changes in cleaved-Prm2 coding sequence are significantly correlated to sperm head width and elongation in rodents. Contrary to expectations, a significant effect of sexual selection was not found on either domain or clade.
CONCLUSIONS
Mature-PRM2 may be free to evolve under less constraint due to the existence of PRM1 as a more conserved and functionally redundant copy. The cleaved-PRM2 domain seems to play an important role in sperm head shaping. However, sexual selection on its sequence may be difficult to detect until it is identified which sperm head phenotype (shape and size) confers advantages for sperm performance in different mammalian clades.
Topics: Animals; Biological Evolution; Male; Mating Preference, Animal; Primates; Protamines; Rodentia; Selection, Genetic; Sperm Head; Spermatozoa
PubMed: 26801756
DOI: 10.1186/s12862-016-0588-1 -
Journal of Thrombosis and Haemostasis :... Sep 2018Essentials Bovine (HBI) and porcine (HPI) heparins differ in structure and anticoagulant activity. Protamine-neutralization was evaluated on a variety of... (Comparative Study)
Comparative Study
UNLABELLED
Essentials Bovine (HBI) and porcine (HPI) heparins differ in structure and anticoagulant activity. Protamine-neutralization was evaluated on a variety of physical-chemical methods. HBI requires more protamine than HPI to fully neutralize its anticoagulant activity. Protamine preferentially removes higher-sulfated chains of HBI while HPI is evenly precipitated.
SUMMARY
Background Protamine neutralization is an essential step for the safe use and inactivation of the unfractionated heparin (UFH) that is widely employed in surgical and non-surgical procedures involving extracorporeal circulation. Objective To compare protamine neutralization of different pharmaceutical-grade UFHs prepared from porcine or bovine intestine (HPI and HBI, respectively). HBI has approximately half the anticoagulant potency of HPI, mostly as consequence of its fraction enriched with N-sulfated α-glucosamine disaccharides. Methods Protamine neutralization of HPI and HBI was evaluated with in vitro, ex vivo and in vivo assays. We also performed in-depth assessments of the complexation of protamine with these distinct UFHs by using nuclear magnetic resonance and mass spectroscopy. Results HPI and HBI interact similarly with protamine on a mass/mass basis; however, HBI requires more protamine than HPI to have its anticoagulant activity fully neutralized, because of its lower potency, which entails the use of higher doses. Nuclear magnetic resonance spectra revealed that HPI precipitates homogeneously with protamine. On the other hand, the low-sulfated fraction of HBI, enriched with N-sulfated α-glucosamine, precipitates at higher concentrations of protamine than the fraction more like HPI, with a preponderance of N,6-disulfated α-glucosamine disaccharides. Finally, mass spectroscopy spectra showed that some of the different peptide components of protamine interact preferentially with the heparins, irrespective of their animal origin. Conclusion Our results have important medical implications, indicating that protamine neutralization of HBI, determined exclusively by point-of-care coagulation assessments, must fail because of its lower-sulfated fraction with reduced anticoagulant activity that could remain in the circulation after the neutralization procedure.
Topics: Animals; Anticoagulants; Biological Assay; Cattle; Chemical Precipitation; Chromatography, Affinity; Disaccharides; Dose-Response Relationship, Drug; Heparin; Heparin Antagonists; Intestinal Mucosa; Mass Spectrometry; Nuclear Magnetic Resonance, Biomolecular; Partial Thromboplastin Time; Protamines; Rats; Species Specificity; Sulfur; Swine
PubMed: 29968421
DOI: 10.1111/jth.14221 -
Blood Mar 2017Anticoagulant therapy-associated bleeding and pathological thrombosis pose serious risks to hospitalized patients. Both complications could be mitigated by developing...
Anticoagulant therapy-associated bleeding and pathological thrombosis pose serious risks to hospitalized patients. Both complications could be mitigated by developing new therapeutics that safely neutralize anticoagulant activity and inhibit activators of the intrinsic blood clotting pathway, such as polyphosphate (polyP) and extracellular nucleic acids. The latter strategy could reduce the use of anticoagulants, potentially decreasing bleeding events. However, previously described cationic inhibitors of polyP and extracellular nucleic acids exhibit both nonspecific binding and adverse effects on blood clotting that limit their use. Indeed, the polycation used to counteract heparin-associated bleeding in surgical settings, protamine, exhibits adverse effects. To address these clinical shortcomings, we developed a synthetic polycation, Universal Heparin Reversal Agent (UHRA), which is nontoxic and can neutralize the anticoagulant activity of heparins and the prothrombotic activity of polyP. Sharply contrasting protamine, we show that UHRA does not interact with fibrinogen, affect fibrin polymerization during clot formation, or abrogate plasma clotting. Using scanning electron microscopy, confocal microscopy, and clot lysis assays, we confirm that UHRA does not incorporate into clots, and that clots are stable with normal fibrin morphology. Conversely, protamine binds to the fibrin clot, which could explain how protamine instigates clot lysis and increases bleeding after surgery. Finally, studies in mice reveal that UHRA reverses heparin anticoagulant activity without the lung injury seen with protamine. The data presented here illustrate that UHRA could be safely used as an antidote during adverse therapeutic modulation of hemostasis.
Topics: Animals; Anticoagulants; Antidotes; Blood Coagulation; Hemorrhage; Heparin; Heparin Antagonists; Humans; Lung; Mice; Polyamines; Polyelectrolytes; Protamines
PubMed: 28034889
DOI: 10.1182/blood-2016-10-747915 -
Biocontrol Science 2015Protamine is an arginine-rich polycationic protein extracted from sperm cells of vertebrates including fishes such as salmon. The purpose of this study was to...
Protamine is an arginine-rich polycationic protein extracted from sperm cells of vertebrates including fishes such as salmon. The purpose of this study was to investigate the suppressive effects of protamine on the growth of oral pathogens for possible usage in dental materials. Minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were determined by the microdilution method. Twelve strains of oral viridans streptococci, Actinomyces naeslundii, Actinomyces odontolyticus, Enterococcus faecalis, Lactobacillus acidophilus, Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Porphyromonas gingivalis and Candida albicans were suppressed by protamine. MIC and MBC values were between 0.009 ~ 20 mg/mL and 0.019 ~ 80 mg/mL, respectively. The bactericidal activities of protamine against susceptible bacterial species were dependent on the concentration of protamine and incubation time. Based on the results of this study, protamine would be a useful compound for the development of antimicrobial agents against oral pathogens in dental materials.
Topics: Animals; Anti-Infective Agents; Bacteria; Candida albicans; Dose-Response Relationship, Drug; Microbial Sensitivity Tests; Microbial Viability; Mouth; Protamines; Salmon; Time Factors
PubMed: 26699859
DOI: 10.4265/bio.20.275 -
The Journal of Thoracic and... Jul 1995Individual aspects of heparin or protamine dosing have been better controlled than previously as useful tests have become available. Although many variables including... (Clinical Trial)
Clinical Trial Randomized Controlled Trial
Individual aspects of heparin or protamine dosing have been better controlled than previously as useful tests have become available. Although many variables including drug potency, drug source, and individual patient response have been separately identified, there has not been an attempt to integrate them into a single management strategy. This study was undertaken to learn whether more precise control of drug variables and patient response would affect blood loss and transfusion requirements. Adult patients having primary cardiac operations were prospectively randomized into two groups. A control group received heparin and protamine by conventional methods. The test group received heparin and protamine according to in vitro predictive tests integrating drugs, tests, and patient response. Supplemental protamine was given in this group only if heparin was specifically found by testing. Anticoagulation in all patients was maintained at an activated coagulation time greater than 400 seconds, and any other treatment for bleeding was at the discretion of the clinical team caring for the patients. Testing and treatment for both groups followed routine practice after patient arrival in the intensive care unit. Test patients received slightly more heparin and a markedly lower dose of protamine than the control patients. Testing identified patients with decreased heparin sensitivity (preoperative heparin therapy) and correctly predicted the effective heparin dose. Supplemental protamine was given twice as often to control patients and frequently when no heparin was detectable (retrospectively). Test patients exhibited less 24-hour chest tube drainage (671 ml versus 1298 ml) and fewer patients received transfusion (9/22 versus 18/24) with fewer donor exposures (22/22 versus 101/24). The management strategy used for heparin and protamine added accuracy and precision, which was associated with improved hemostasis. Although the observation is valid, the mechanism or mechanisms are not completely clear. Nevertheless, it is reasonable to apply basic pharmacologic principles and establishment of consistent, predictable protocols that are beneficial. It is against this background that the efficacy of additional drugs or equipment should be assessed. It is quite possible that only marginal if any improvement in hemostasis may be found in patients having primary, uncomplicated cardiac operation with the addition of more costly drugs or equipment.
Topics: Aged; Analysis of Variance; Blood Loss, Surgical; Blood Transfusion; Cardiac Surgical Procedures; Cardiopulmonary Bypass; Chi-Square Distribution; Drug Administration Schedule; Female; Heparin; Humans; Male; Middle Aged; Prospective Studies; Protamines; Treatment Outcome; Whole Blood Coagulation Time
PubMed: 7609566
DOI: 10.1016/S0022-5223(05)80007-8 -
PLoS Biology May 2022Inherited microorganisms can selfishly manipulate host reproduction to drive through populations. In Drosophila melanogaster, germline expression of the native Wolbachia...
Inherited microorganisms can selfishly manipulate host reproduction to drive through populations. In Drosophila melanogaster, germline expression of the native Wolbachia prophage WO proteins CifA and CifB cause cytoplasmic incompatibility (CI) in which embryos from infected males and uninfected females suffer catastrophic mitotic defects and lethality; however, in infected females, CifA expression rescues the embryonic lethality and thus imparts a fitness advantage to the maternally transmitted Wolbachia. Despite widespread relevance to sex determination, evolution, and vector control, the mechanisms underlying when and how CI impairs male reproduction remain unknown and a topic of debate. Here, we use cytochemical, microscopic, and transgenic assays in D. melanogaster to demonstrate that CifA and CifB proteins of wMel localize to nuclear DNA throughout the process of spermatogenesis. Cif proteins cause abnormal histone retention in elongating spermatids and protamine deficiency in mature sperms that travel to the female reproductive tract with Cif proteins. Notably, protamine gene knockouts enhance wild-type CI. In ovaries, CifA localizes to germ cell nuclei and cytoplasm of early-stage egg chambers; however, Cifs are absent in late-stage oocytes and subsequently in fertilized embryos. Finally, CI and rescue are contingent upon a newly annotated CifA bipartite nuclear localization sequence. Together, our results strongly support the Host modification model of CI in which Cifs initially modify the paternal and maternal gametes to bestow CI-defining embryonic lethality and rescue.
Topics: Animals; Cytoplasm; Drosophila melanogaster; Female; Male; Prophages; Protamines; Spermatozoa; Wolbachia
PubMed: 35609042
DOI: 10.1371/journal.pbio.3001584 -
European Journal of Vascular and... Apr 2021
Topics: Endarterectomy, Carotid; Heparin Antagonists; Humans; Myocardial Infarction; Protamines; Stroke
PubMed: 33640281
DOI: 10.1016/j.ejvs.2021.01.046