Slide 2 of 5 of Coagulación sanguínea. VÍA EXTRÍNSECA; 2. Vía Intrínseca; 3. Conversión de la Vías y cascada de la coagulación. Enzimas que actuan en la coagulación.c. Asignatura: .. Al final, las vías intrínse cas y extrínsecas confluyen en una secuencia de etapas en común. hasta. Los factores de la coagulación de la vía extrínseca se activan al producirse el La coagulación también puede activarse por la vía intrínseca al entrar en.
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Screening for anticoagulant substances in some marine macroalgae. The coagulation disorders have increased in the last decades and no new substances had been discovered that could regulate this illness. This fact makes the discovery of new anticoagulant substances a priority issue in research. Forty nine seaweed species collected off shore of several localities of Gulf of Mexico and Mexican Caribbean sea were screened in order to detect anticoagulant activity in both intrinsic and extrinsic pathways of clot formation.
Standardized plasma coagulation tests thrombin and prothrombin time were used. Heparin, a sulphated glycosaminoglycan wide used in oral anticoagulant therapy, was used as reference in both proofs. The results showed that four species presented potent anticoagulant activity same as heparin in the two pathways: Anadyomene stellataCaulerpa cupressoides ChlorophytaLobophora variegata Phaeophyta and Liagora farinosa Rhodophyta.
Caulerpa paspaloides Chlorophyta was active only in the thrombin time test. Other seven species presented a slightly anticoagulant activity. We considered that algal extracts have substances capable of inhibit clot formation in the last steps of the coagulation cascade.
The extracts could act preventing the conversion of prothrombin to thrombin, also they could act stopping the transformation of fibrinogen to convert it to fibrin o even in the polymerization of this last molecule. This is the first report of anticoagulant activity in Anadyomene stellataLobophora variegata and Liagora farinosa.
We can concluded that these species can be considered as potentially alternative source of anticoagulant molecules. Anticoagulant activity, marine algae, Gulf of Mexico, heparin.
Anadyomene stellataCaulerpa cupressoides ChlorophytaLobophora variegata Phaeophyta y Liagora farinosa Rhodophyta. Caulerpa paspaloides Chlorophyta fue activa solamente en el tiempo de trombina.
Se reporta por primera vez la actividad anticoagulante de Anadyomene stellataLobophora variegata y Liagora farinosa. Se concluye que estas especies pueden ser consideradas como una fuente alternativa de nuevos anticoagulantes.
Thrombosis is a health problem that affects many people in the world. The discovery of alternative anticoagulant molecules must be an important task for scientists. It has been done research in anticoagulant activity of polysaccharides and glycosaminoglycans of diverse sources such as: These molecules have different degree of sulfate in their structure and therefore are capable of substitute heparin Farias et al.
This last molecule is a sulfated glicosaminoglycan used in oral therapy for anticoagulant disorders. It is known that species of Chlorophyta synthesized polydisperse heteropolysaccarides with low sulfate content, glucoronoxilorhamans, glucoronoxilorhamagalactans and xyloarabinogalactans, some of them with a potent anticoagulant activity Uehara et al.
It has been reported also that brown algae have a potent anticoagulant activity in fucoidans Chevolot et al.
Recently, a group of scientists had stand out the potentiality of some proteins and proteoglycans capable of interfere with blood clotting cascade, particularly from Codium Matsubara et al.
The research effort has been focused on one genus, forgotten the basic detection of different algae as a potential source of alternative anticoagulant molecules. This work deals with the detection of anticoagulant activity in extrimseca from several localities along the Mexican Atlantic coast.
We collected algal material along the central coast of Veracruz, and some localities of Campeche, Yucatan and Quintana Roo States in order to have samples of the coast of the Atlantic Ocean in Mexico Gulf of Mexico and Ciagulacion sea. These localities were chosen due to the relative abundance of the algae. The sites of collection of Veracruz state were: In Campeche state we colleted phycological material in: In the central and eastern zones there are patches of sea-grass Halodule wrightiithe western part with algae.
The samples for this study were manually collected from the seven localities described above, from the Gulf of Mexico and Mexican Caribbean sea during May to October figure 1were classified by genus and transported frozen to the laboratory using solid CO 2. In the laboratory the material was thawed dr room temperature and a fraction of this was preserved in glycerinated formaldehyde for species determination and Voucher organisms, this specimens were kept in our laboratory as internal reference material.
Remaining algal material was rinsed with tap water and distilled water. Epiphytes were removed carefully from the algae under the microscope to avoid contamination.
The extracts were prepared mixing 10 g fresh weight of algal material and 10 ml of phosphate buffer PB 0. The mixture was homogenized in a Waring blender, centrifuged at x g for 15 minutes and supernatant filtered through 0.
Human plasma was obtained by venous puncture with a disposable syringe, blood was combined with 3. As anticoagulant time reference 6. We considered an algal extract with anticoagulant activity similar to heparin when this impede the clot formation during 10 minutes or more.
Detección de sustancias anticoagulantes en algunas macroalgas marinas
Intrijseca for algal extracts in both anticoagulant tests are in table 1. Forty nine species were tested, 14 from Chlorophyta, 8 from Phaeophyta and 27 belonging to Rhodophyta. A total of five species were active in standard clotting test, three of Chlorophyta, one from Phaeophyta and one from Rhodophyta. The extracts of Anadyomene stellata Wulfen C.
Agardh, Caulerpa cupressoides West in Vahl C. Agardh, ChlorophytaLobophora variegata Lamoroux G Phaeophyta and Liagora farinosa Lamouroux Viaa were as potent as heparin impeding the clot formation in both thrombin and prothrombin time tests.
One of the extracts of C. The extract of L. A delay in clot formation less than two minutes was observed in prothrombin time test for this species from Chlorophyta: Similar results of slightly anticoagulant potency were observed but in thrombin time test for C.
Agardh Rhodophyta retarded the coagulation process of human plasma in both anticoagulant tests for less than two minutes period and more than one minute.
Factor de coagulación XI
We also detected a variation in the anticoagulant potency, a change in the anticoagulant activity related with the intrinsic or extrinsic pathways of coagulation or even the disappearance of the anticoagulant activity in both test of Caulerpa cupressoidesC.
We considered that extracts who acted on both path-ways of clot formation, affect the cascade of coagulation in the point of convergence, that is in transformation of fibrinogen to fibrin. We can concluded that some substances present in the algal extract can act on any of the enzyme or substrate inhibiting the transformation of prothrombin to thrombin or in the activation process of fibrinogen to fibrin.
Alternatively coagulacionn possible that algal substances acted impeding the polymerization of fibrin for clot formation. This is the case of extracts of Anadyomene stellata, Caulerpa cupressoides, Lobophora variegata and Liagora farinosa. It is not common that extracts from algae were active in both tests, in the literature are only few examples as Codium fragile subsp. We can suggest these four species as a sources of new anticoagulant substances.
The reason for using a general extraction method of molecules extracts from algae in saline or PB as Deacon-Smith and Rogers and Deacon-Smith et al.
Supporting the use of this method is the evidence that the results of Deacon et al. Our results showed four species with similar activity susceptible of further research for isolation and characterizations of active substances. The results showed other algae with slightly inhibition of clot formation activity, it is not common to consider this species for further edtrinseca, nevertheless the retardation of formation of clot by Penicillus capitatusa species evolutionary related to Halimeda exxtrinseca Vroom et al.
It is relevant to point out the dependence of anticoagulant potency due to the locality where algae grows, also the date of collection and thus, the climate season is other factor that could influence the synthesis of compounds, particularly in the brown alga Lobophora variegata we observed cascxda double anticoagulant action in sample collected in May ofbut six months later Novembersame specie only was active in the prothrombin time test.
Finally, sample collected in April of change the anticoagulant activity been active only in the thrombin time test. Similar results were detected in Caulerpa cupressoides extracts collected in three occasions, in this case even the total absence of activity was detected in one sample.
These variation has been suggested as been influenced by geographical factors such as climate and locality and has been probed with primary metabolites as exrrinseca by Ingram and Fabregas et al. However we consider more research has to be done, focused to this topic, in order to probe this hypothesis. Biological activity of extracts from some Mediterranean macrophytes. Occurrence of heparin in the invertebrate Styela plicata Tunicata is restricted to cell layers facing the outside environment.
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Biochimica et Biophysica Acta Current views on blood coagulation and haemostatic mechanism. Blood coagulation and haemostasis. Lectins and lectin-like molecules in lower plants. Developments in Comparative Immunology 9: