Action of Varespladib (LY-315920), a Phospholipase A2 Inhibitor, on the Enzymatic, Coagulant and Haemorrhagic Activities of Lachesis muta rhombeata (South-American Bushmaster) Venom

Varespladib (VPL) was primarily developed to treat inflammatory disturbances associated with high levels of serum phospholipase A2 (PLA2). VPL has also demonstrated to be a potential antivenom support agent to prevent PLA2-dependent effects produced by snake venoms. In this study, we examined the action of VPL on the coagulant, haemorrhagic and enzymatic activities of Lachesis muta rhombeata (South-American bushmaster) venom. Conventional colorimetric enzymatic assays were performed for PLA2, caseinolytic and esterasic activities; in vitro coagulant activities for prothrombin time (PT) and activated partial thromboplastin time (aPTT) were performed in rat citrated plasma through a quick timer coagulometer, whereas the dimensions of haemorrhagic haloes obtained after i.d. injections of venom in Wistar rats were determined using ImageJ software. Venom (1 mg/ml) exhibited accentuated enzymatic activities for proteases and PLA2in vitro, with VPL abolishing the PLA2 activity from 0.01 mM; VPL did not affect caseinolytic and esterasic activities at any tested concentrations (0.001–1 mM). In rat citrated plasma in vitro, VPL (1 mM) alone efficiently prevented the venom (1 mg/ml)-induced procoagulant disorder associated to extrinsic (PT) pathway, whereas its association with a commercial antivenom successfully prevented changes in both intrinsic (aPTT) and extrinsic (PT) pathways; commercial antivenom by itself failed to avoid the procoagulant disorders by this venom. Venom (0.5 mg/kg)-induced hemorrhagic activity was slightly reduced by VPL (1 mM) alone or combined with antivenom (antivenom:venom ratio 1:3 ‘v/w’) in rats, with antivenom alone producing no protective action on this parameter. In conclusion, VPL does not inhibit other major enzymatic groups of L. m. rhombeata venom, with its high PLA2 antagonize activity efficaciously preventing the venom-induced coagulation disturbances.

Effects of 200cH medications on mice bone marrow cells and macrophages

Paracelsus once wrote: "All things are poison and nothing is without poison, only the dose permits something not to be poisonous." Latter Hahnemann formulated the law of similars, preparations which cause certain symptoms in healthy individuals if given in diluted form to patients exhibiting similar symptoms will cure it. Highly diluted natural complexes prepared according to Hahnemann’s ancient techniques may represent a new form of immunomodulatory therapy. The lack of scientific research with highly diluted products led us to investigate the in vivo and in vitro actions of commonly used medications. Here we describe the results of experimental studies aimed at verifying the effects of Mercurius solubilis, Atropa Belladonna, Lachesis muta and Bryonia alba. All medications were at 200cH dilution. Animals were maintained for 7 days and were allowed to drink the medications, which were prepared in a way that the final dilution and agitation (200cH) was performed in drinking water. The medication bottle was changed and sucussed every afternoon. Co-culture of non treated mice bone marrow cells and in vitro treated peritoneal macrophages were also performed. After animal treatment the bone marrow cells were immunophenotyped with hematopoietic lineage markers on a flow cytometer. We have determined CD11b levels on bone marrow cells after culture and co-culture with treated macrophages and these macrophages were processed to scanning electron microscopy. We have observed by morphological changes that macrophages were activated after all treatments. Mercurius solubilis treated mice showed an increase in CD3 expression and in CD11b on nonadherent bone marrow cells after co-culture with in vitro treatment. Atropa Belladonna increased CD45R and decreased Ly-6G expression on bone marrow cells after animal treatment. Lachesis muta increased CD3, CD45R and, CD11c expression and decreased CD11b ex vivo and in nonadherent cells from co-culture. Bryonia alba increased Ly-6G, CD11c and CD11b expression ex vivo and when in co-culture CD11b was increased in adherent cells as well as decreased in nonadherent cells. With these results we have demonstrated that highly diluted medications act on immune cells activating macrophages, and changing the expression profile of hematopoietic lineage markers. Highly diluted medications are less toxic and cheaper than other commonly used medications and based on our observations, it is therefore conceivable that this medications which are able to act on bone marrow and immune cells may have a potential therapeutic use in clinical applications in diseases were the immune system is affected and also as regenerative medicine as it may allow proliferation and differentiation of progenitor cells.

Small Angle X-ray Scattering, Molecular Modeling, and Chemometric Studies from a Thrombin-Like (Lmr-47) Enzyme of Lachesis m. rhombeata Venom

Introduction: Snakebite envenomation is considered a neglected tropical disease, and SVTLEs critical elements are involved in serious coagulopathies that occur on envenoming. Although some enzymes of this group have been structurally investigated, it is essential to characterize other proteins to better understand their unique properties such as the Lachesis muta rhombeata 47 kDa (Lmr-47) venom serine protease. Methods: The structure of Lmr-47 was studied in solution, using SAXS, DLS, CD, and in silico by homology modeling. Molecular docking experiments simulated 21 competitive inhibitors. Results: At pH 8.0, Lmr-47 has an Rg of 34.5 ± 0.6 Å, Dmax of 130 Å, and SR of 50 Å, according to DLS data. Kratky plot analysis indicates a rigid shape at pH 8.0. Conversely, the pH variation does not change the center of mass’s intrinsic fluorescence, possibly indicating the absence of fluorescent amino acids in the regions affected by pH variation. CD experiments show a substantially random coiled secondary structure not affected by pH. The low-resolution model of Lmr-47 presented a prolate elongated shape at pH 8.0. Using the 3D structure obtained by molecular modeling, docking experiments identified five good and three suitable competitive inhibitors. Conclusion: Together, our work provided insights into the structure of the Lmr-47 and identified inhibitors that may enhance our understanding of thrombin-like family proteins.

ANÁLISIS BIOQUÍMICO DE DOS FRACCIONES CON ACCIÓN ANTICOAGULANTE DE LAS HOJAS DE Oenothera rosea “CHUPASANGRE”

Tradicionalmente las hojas de Oenothera rosea “chupasangre” son usadas para reducir los hematomas, por lo que, esta investigación estuvo dirigida a la evaluación de los componentes capaces de retardar la coagulación sanguínea. Del extracto etanólico de O. rosea se separó por cromatografía de capa fina en celulosa, usando etanol: agua (1:5), dos fracciones F-2 y F-5, que luego fueron preincubadas por 10 minutos con trombina y el veneno de la serpiente Lachesis muta, rico en Enzima Semejante a Trombina (EST) y luego se midió la actividad coagulante sobre plasma humano citratado y fibrinógeno bovino (Fb), así como el sustrato cromogénico BApNA. Los resultados mostraron que F-2 alargó el tiempo de coagulación sobre Fb en 58,58 % y el F-5 en 67,78 %, mientras que usando veneno los retardos fueron para F-2 10,67 % y F-5 36,27 %. Usando plasma, los valores fueron para F-2 34,14 % y F-5 70,59 %. Asimismo, empleando trombina la actividad amidolítica se redujo en F-2 48,48 % y F-5 67,32 %, mientras que con la EST de L. muta la inhibición de F-2 50,20 % y F-5 69,10%. Mediante estos ensayos in vitro se concluye que F-2 y F-5 podrían ser flavonoides anticoagulantes, con probable acción antitrombolítica.

Evaluation of Haemolytic and Morphological Changes in Red Blood Cell on Administration of Lachesis Muta 30, 200 and 1M in - Vitro Study

Snake venom has haemolytic action on the blood and reduces the power of its coagulability, with the result that a bloody serum continue to oozes out from wound for many hours.