scholarly journals Role of Ribosomal RNA Released from Red Cells in Blood Coagulation in Zebrafish and Humans

Author(s):  
Abdulmajeed Alharbi ◽  
Neha Iyer ◽  
Ayah AlQaryoute ◽  
Revathi Raman ◽  
David Burks ◽  
...  

Hemolytic disorders are characterized by hemolysis and are prone to thrombosis. Previously, it has been shown that the RNA released from damaged blood cells activates clotting. However, the nature of RNA released from hemolysis is still elusive. We found that after hemolysis, RBCs from both zebrafish and humans released 5.8S rRNA. This RNA activated coagulation in zebrafish and human plasmas. Using both natural and synthetic 5.8S rRNA and its truncated fragments, we found that the 3'-end 26 nucleotide-long RNA (3'-26 RNA) and its stem-loop secondary structure were necessary and sufficient for clotting activity. Corn trypsin inhibitor (CTI), a coagulation factor XII (FXII) inhibitor blocked 3'-26 RNA-mediated coagulation activation of both zebrafish and human plasma. CTI also inhibited zebrafish coagulation in vivo. 5.8S rRNA monoclonal antibody inhibited both 5.8S rRNA- and 3'-26 RNA-mediated zebrafish coagulation activity. Both 5.8S rRNA and 3'-26 RNA activates normal human plasma but did not activate FXII-deficient human plasma. Taken together, these results suggested that the activation of zebrafish plasma is via FXII-like protein. Since zebrafish has no FXII and hepatocyte growth factor activator (Hgfac) has sequence similarities to FXII, we knocked down the hgfac in adult zebrafish. We found that plasma from this knockdown fish does not respond to 3'-26 RNA. In conclusion, we identified 5.8S rRNA released in hemolysis activates clotting in human and zebrafish plasma. Only 3'-end 26 nucleotides of the 5.8S rRNA is needed for the clotting activity. Furthermore, we showed that fish Hgfac plays a role in 5.8S rRNA-mediated activation of coagulation.

Author(s):  
D H Osmond ◽  
S R Tatemichi ◽  
E A Wilczynski ◽  
A D Purdon

We have demonstrated that human plasma “prorenin”, an inactive precursor of the blood pressure regulating enzyme renin, can be activated by cold, e.g. -4 to +4°C for 1-30 days (Can. J. Physiol. Pharmacol. 51:705, 1973). Several workers have reported cold activation of the coagulation system. Suspecting a link between these two cold- activated enzyme systems, we established that in factor XII deficient plasma, the rate of cold activation of prorenin is halved (Lancet i, 1313, 1978). Trypsinization of plasma can mimic within 1 minute the effect of prolonged cold (Circ. Res. Suppl . 1, 41:171, 1977), and can overcome specific coagulation factor deficiencies in varying degrees. FXII, VII, V, and especially FX deficient plasmas, all have subnormal basal active renin levels, implying an impaired state of prorenin conversion in vivo. FXII deficientplasma activates least by cold, suggesting special importance of FXII for operation of cold activation. All the plasmas activate better with 0.5 mg trypsin/ml plasma than with cold, except FX, suggesting that it especially mediates tryptic activation. Increasing the trypsin concentration corrects for factor deficiencies in varying degrees, implying some non-specificity and interchangeability of factor requirements for prorenin activation. Our data point to a hierarchy of factor importance, and to a “cascade7#x201D; of prorenin activation, by which plasma renin content can be rapidly increased. Thus, plasma renin activity is a function of renal release of renin, plus renin formation from renal (and possibly extrarenal) prorenin by an activation process involving the coagulation system.


1992 ◽  
Vol 67 (04) ◽  
pp. 440-444 ◽  
Author(s):  
Hiroko Tsuda ◽  
Toshiyuki Miyata ◽  
Sadaaki Iwanaga ◽  
Tetsuro Yamamoto

SummaryThe analysis of normal human plasma by fibrin autography revealed four species of plasminogen activator (PA) activity related to tissue-type PA, factor XII, prekallikrein and urokinase-type PA (u-PA). The u-PA activity increased significantly by incubating plasma with dextran sulfate. This increase was coincident with both the cleavage of factor XII and the complex formation of activated factor XII with its plasma inhibitors, which were determined by immunoblotting procedure. The dextran sulfate-dependent activation of u-PA required both factor XII and prekallikrein, but did not require either plasminogen or factor XI. High molecular weight kininogen was required only at a low concentration of dextran sulfate. Thus the results indicate that the factor XII and prekallikrein-mediated activation of single chain u-PA (scu-PA) operates as a major pathway of scu-PA activation in whole plasma in contact with dextran sulfate.


1992 ◽  
Vol 67 (01) ◽  
pp. 060-062 ◽  
Author(s):  
J Harsfalvi ◽  
E Tarcsa ◽  
M Udvardy ◽  
G Zajka ◽  
T Szarvas ◽  
...  

Summaryɛ(γ-glutamyl)lysine isodipeptide has been detected in normal human plasma by a sensitive HPLC technique in a concentration of 1.9-3.6 μmol/1. Incubation of in vitro clotted plasma at 37° C for 12 h resulted in an increased amount of isodipeptide, and there was no further significant change when streptokinase was also present. Increased in vivo isodipeptide concentrations were also observed in hypercoagulable states and during fibrinolytic therapy.


VASA ◽  
2003 ◽  
Vol 32 (3) ◽  
pp. 145-148 ◽  
Author(s):  
Kuss ◽  
Heidrich ◽  
Koettgen

Background: The study was designed to evaluate if there is any evidence of a hyperfibrinolytic bleeding-risk under systemic treatment with prostaglandin E1 (PGE1) of patients with peripheral arterial disease (PAD). Patients and methods: The in vivo effect of PGE1 on the fibrinolytic and hemostatic process was tested on 15 patients before and after treatment with Alprostadil for 21 days using D-dimers (DD), fibrinogen, prothrombin time (PT), partial thromboplastin time (PTT), antithrombin (AT), ProC-Global®, plasminogen, plasminogen activator inhibitor activity (PAI), alpha2-antiplasmin, coagulation factor XII, basal and activated fibrinolytic capacity (fib. cap.). Results: There was no significant difference in DD, fibrinogen, PT, PTT, AT, ProC-Global®, plasminogen, PAI, alpha2-antiplasmin, coagulation factor XII, basal and activated fibrinolytic capacity observed after the treatment. Conclusion: Summarizing this study there is no hyperfibrinolytic bleeding-risk after the systemic therapy with Alprostadil to be expected.


2004 ◽  
Vol 92 (09) ◽  
pp. 503-508 ◽  
Author(s):  
Hans-Ulrich Pauer ◽  
Thomas Renné ◽  
Bernhard Hemmerlein ◽  
Tobias Legler ◽  
Saskia Fritzlar ◽  
...  

SummaryTo analyze the biological role of factor XII (FXII, Hageman Factor) in vivo, we generated mice deficient for FXII using a gene targeting approach on two distinct genetic backgrounds, i.e. mixed C57Bl/6J X 129X1/SvJ and inbred 129X1/SvJ. Homozygous FXII knockout (FXII-/-) mice showed no FXII plasma activity and had a markedly prolonged activated partial thromboplastin time (aPTT). In contrast, coagulation factors XI, VIII, IX, X,VII,V, II and fibrinogen did not differ between FXII-/- mice and their wild-type littermates. Heterozygous matings segregated according to the Mendelian inheritance indicating that FXII deficiency does not increase fetal loss. Furthermore, matings of FXII-/- males and FXII-/females resulted in normal litter sizes demonstrating that total FXII deficiency in FXII-/females does not affect pregnancy outcome. Also, gross and histological anatomy of FXII-/mice was indistinguishable from that of their wild-type littermates on both genetic backgrounds. Thus it appears that deficiency of murine FXII does not cause thrombophilia or impaired fibrinolysis in vivo. These results indicate that FXII deficiency does not affect hemostasis in vivo and we anticipate that the FXII-/mice will be helpful to elucidate the biological role(s) of FXII in health and disease.


2020 ◽  
Author(s):  
Eugénie Garnier ◽  
Damien Levard ◽  
Carine Ali ◽  
Yannick Hommet ◽  
Tiziana Crepaldi ◽  
...  

Abstract Background Factor XII (FXII) is a serine protease that participates in the intrinsic coagulation pathway. Several studies have shown that plasmatic FXII exert a deleterious role in cerebral ischemia and traumatic brain injury by promoting thrombo-inflammation. Nevertheless, the direct impact of FXII on neuronal cell fate remains unknown.Methods We investigated whether FXII influenced neuronal death induced in vivo by stereotaxic injection of N-methyl-D-Aspartate (NMDA) and in vitro by serum deprivation of cultured neurons.Results We found that FXII reduced brain lesions induced in vivo and protected cultured neurons from apoptosis through a growth factor-like effect. This mechanism was triggered by direct interaction with epidermal growth factor (EGF) receptor, activation of this receptor and engagement of anti-apoptotic intracellular pathways. Interestingly, the “proteolytically” active and two-chain form of FXII, αFXIIa, exerted additional protective effects by converting the pro-form of hepatocyte growth factor (HGF) into its mature form, which in turn activated HGF receptor (HGFR/c-Met) pathway. Lastly, the use of non-proteolytic FXII (αFXIIa-PPACK) unveiled an alternative EGFR and HGFR co-activation pathway, through co-receptor transphosphorylation. Conclusion This study describes novel mechanisms of action of FXII and discloses neurons as target cells for the protective effects of single and double-chain forms of FXII.


Blood ◽  
2012 ◽  
Vol 120 (22) ◽  
pp. 4296-4303 ◽  
Author(s):  
Thomas Renné ◽  
Alvin H. Schmaier ◽  
Katrin F. Nickel ◽  
Margareta Blombäck ◽  
Coen Maas

Abstract Coagulation factor XII (FXII, Hageman factor, EC = 3.4.21.38) is the zymogen of the serine protease, factor XIIa (FXIIa). FXII is converted to FXIIa through autoactivation induced by “contact” to charged surfaces. FXIIa is of crucial importance for fibrin formation in vitro, but deficiency in the protease is not associated with excessive bleeding. For decades, FXII was considered to have no function for coagulation in vivo. Our laboratory developed the first murine knockout model of FXII. Consistent with their human counterparts, FXII−/− mice have a normal hemostatic capacity. However, thrombus formation in FXII−/− mice is largely defective, and the animals are protected from experimental cerebral ischemia and pulmonary embolism. This murine model has created new interest in FXII because it raises the possibility for safe anticoagulation, which targets thrombosis without influence on hemostasis. We recently have identified platelet polyphosphate (an inorganic polymer) and mast cell heparin as in vivo FXII activators with implications on the initiation of thrombosis and edema during hypersensitivity reactions. Independent of its protease activity, FXII exerts mitogenic activity with implications for angiogenesis. The goal of this review is to summarize the in vivo functions of FXII, with special focus to its functions in thrombosis and vascular biology.


1988 ◽  
Vol 59 (02) ◽  
pp. 151-161 ◽  
Author(s):  
Bernhard Lämmle ◽  
Bruce L Zuraw ◽  
Mary Jo Heeb ◽  
Hans Peter Schwarz ◽  
Mauro Berrettini ◽  
...  

SummaryA method for the quantitative assay of native single chain and kallikrein cleaved two-chain high molecular weight (HMW)-kininogen in plasma is described. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of whole plasma is followed by electrotransfer of the electropherogram to nitrocellulose membranes and detection of the blotted HMW-kininogen with its physiologic ligands, radiolabeled plasma prekallikrein or radiolabeled factor XI. Using unreduced SDS-PAGE cleaved two-chain HMW-kininogen (Mr ∼107,000 and 95,000), is elec-trophoretically separated from uncleaved single chain HMW-kininogen (Mr ∼150,000). Counting the radioactivity of the nitrocellulose pieces corresponding to cleaved HMW-kininogen permits its quantitative measurement by comparison with standards consisting of decreasing amounts of fully dextran sulfate activated normal human plasma. Single chain HMW-kininogen is similarly assayed using reduced SDS-PAGE and unactivated normal human plasma standards.This technique is highly specific and sensitive to about 50 ng of either cleaved or uncleaved HMW-kininogen. Varying amounts of cleaved HMW-kininogen were found in a small series of plasmas from patients suffering from various inflammatory conditions. Higher levels of in vivo cleaved HMW-kininogen were observed during acute attacks of hereditary angioedema due to Cl-inhibitor deficiency. This technique may be useful for the assessment of the degree of in vitro or in vivo activation of the contact system.


2018 ◽  
Vol 19 (11) ◽  
pp. 3435 ◽  
Author(s):  
Tsuyoshi Fukushima ◽  
Shuichiro Uchiyama ◽  
Hiroyuki Tanaka ◽  
Hiroaki Kataoka

Hepatocyte growth factor (HGF) promotes pleiotropic signaling through its specific receptor tyrosine kinase, MET. As such, it has important roles in the regeneration of injured tissues. Since HGF is produced mainly by mesenchymal cells and MET is expressed in most epithelial, endothelial and somatic stem cells, HGF functions as a typical paracrine growth factor. HGF is secreted as an inactive precursor (proHGF) and requires proteolytic activation to initiate HGF-induced MET signaling. HGF activator (HGFAC) is a serum activator of proHGF and produces robust HGF activities in injured tissues. HGFAC is a coagulation factor XII-like serine endopeptidase that circulates in the plasma as a zymogen (proHGFAC). Thrombin, kallikrein-related peptidase (KLK)-4 or KLK-5 efficiently activates proHGFAC. The activated HGFAC cleaves proHGF at Arg494-Val495, resulting in the formation of the active disulfide-linked heterodimer HGF. Macrophage stimulating protein, a ligand of RON, is also activated by HGFAC in vivo. Although HGFAC functions primarily at the site of damaged tissue, a recent report has suggested that activated HGFAC relays a signal to stem cells in non-injured tissues via proHGF activation in the stem cell niche. This review focuses on current knowledge regarding HGFAC-mediated proHGF activation and its roles in tissue regeneration and repair.


1985 ◽  
Vol 839 (1) ◽  
pp. 57-61 ◽  
Author(s):  
Kumudini M. Weerasinghe ◽  
Michael F. Scully ◽  
Vijay V. Kakkar

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