Supplementary data for article: Villalta-Romero, F.; Borro, L.; Mandić, B.; Escalante, T.; Rucavado, A.; Gutierrez, J. M.; Neshich, G.; Tasic, L. Discovery of Small Molecule Inhibitors for the Snake Venom Metalloprotease BaP1 Using in Silico and in Vitro Tests. Bioorganic and Medicinal Chemistry Letters 2017, 27 (9), 2018–2022. https://doi.org/10.1016/j.bmcl.2017.03.007

Supplementary material for: [ https://doi.org/10.1016/j.bmcl.2017.03.007]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2449]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/3001

Supplementary data for article: Villalta-Romero, F.; Borro, L.; Mandić, B.; Escalante, T.; Rucavado, A.; Gutierrez, J. M.; Neshich, G.; Tasic, L. Discovery of Small Molecule Inhibitors for the Snake Venom Metalloprotease BaP1 Using in Silico and in Vitro Tests. Bioorganic and Medicinal Chemistry Letters 2017, 27 (9), 2018–2022. https://doi.org/10.1016/j.bmcl.2017.03.007

Supplementary material for: [ https://doi.org/10.1016/j.bmcl.2017.03.007]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2449]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/3001

Extracts of Renealmia alpinia (Rottb.) MAAS Protect against Lethality and Systemic Hemorrhage Induced by Bothrops asper Venom: Insights from a Model with Extract Administration before Venom Injection

Renealmia alpinia (Rottb.) MAAS, obtained by micropropagation (in vitro) and wild forms have previously been shown to inhibit some toxic activities of Bothrops asper snake venom if preincubated before injection. In this study, assays were performed in a murine model in which extracts were administered for three days before venom injection. R. alpinia extracts inhibited lethal activity of B. asper venom injected by intraperitoneal route. Median Effective Dose (ED50) values were 36.6 ± 3.2 mg/kg and 31.7 ± 5.4 mg/kg (p > 0.05) for R. alpinia wild and in vitro extracts, respectively. At a dose of 75 mg/kg, both extracts totally inhibited the lethal activity of the venom. Moreover, this dose prolonged survival time of mice receiving a lethal dose of venom by the intravenous route. At 75 mg/kg, both extracts of R. alpinia reduced the extent of venom-induced pulmonary hemorrhage by 48.0% (in vitro extract) and 34.7% (wild extract), in agreement with histological observations of lung tissue. R. alpinia extracts also inhibited hemorrhage in heart and kidneys, as evidenced by a decrease in mg of hemoglobin/g of organ. These results suggest the possibility of using R. alpinia as a prophylactic agent in snakebite, a hypothesis that needs to be further explored.Comité para el Desarrollo de la Investigación and Sostenibilidad 2014–2015///ColombiaUniversidad de Antioquia///ColombiaComité Nacional para el Desarrollo de la Investigación//CONADI/ColombiaUniversidad Cooperativa de Colombia///ColombiaUniversidad de Costa Rica//UCR/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP

Analysis of TcdB Proteins within the Hypervirulent Clade 2 Reveals an Impact of RhoA Glucosylation on Clostridium difficile Proinflammatory Activities

Clostridium difficile strains within the hypervirulent clade 2 are responsible for nosocomial outbreaks worldwide. The increased pathogenic potential of these strains has been attributed to several factors but is still poorly understood. During a C. difficile outbreak, a strain from this clade was found to induce a variant cytopathic effect (CPE), different from the canonical arborizing CPE. This strain (NAP1V) belongs to the NAP1 genotype but to a ribotype different from the epidemic NAP1/RT027 strain. NAP1V and NAP1 share some properties, including the overproduction of toxins, the binary toxin, and mutations in tcdC. NAP1V is not resistant to fluoroquinolones, however. A comparative analysis of TcdB proteins from NAP1/RT027 and NAP1V strains indicated that both target Rac, Cdc42, Rap, and R-Ras but only the former glucosylates RhoA. Thus, TcdB from hypervirulent clade 2 strains possesses an extended substrate profile, and RhoA is crucial for the type of CPE induced. Sequence comparison and structural modeling revealed that TcdBNAP1 and TcdBNAP1V share the receptor-binding and autoprocessing activities but vary in the glucosyltransferase domain, consistent with the different substrate profile. Whereas the two toxins displayed identical cytotoxic potencies, TcdBNAP1 induced a stronger proinflammatory response than TcdBNAP1V as determined in ex vivo experiments and animal models. Since immune activation at the level of intestinal mucosa is a hallmark of C. difficile-induced infections, we propose that the panel of substrates targeted by TcdB is a determining factor in the pathogenesis of this pathogen and in the differential virulence potential seen among C. difficile strains.Wellcome Trust, United States a Trevor D Lawley bajo el número 098051Consejo Nacional de Rectores/[803-B1-654]/CONARE/Costa RicaConsejo Nacional de Rectores/[803-B4-652]/CONARE/Costa RicaUniversidad de Costa Rica/[803-B5-107]/UCR/Costa RicaUniversidad de Costa Rica/[803-B5-108]/UCR/Costa RicaConsejo Nacional para Investigaciones Científicas y Tecnológicas/[FV-0004-13. HHS]/CONICIT/Costa RicaNational Institutes of Health/[R01AI095755]/NIH/Estados UnidosUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Centro de Investigación en Enfermedades Tropicales (CIET

Experimental pathophysiology of systemic alterations induced by Bothrops asper snake venom

Moderate and severe envenomations by the snake Bothrops asper provoke systemic alterations, such as systemic bleeding, coagulopathy, hypovolemia, hemodynamic instability and shock, and acute renal failure. Systemic hemorrhage is a typical finding of these envenomations, and is primarily caused by the action of P-III snake venom metalloproteinases (SVMPs). This venom also contains a thrombin-like serine proteinase and a prothrombin-activating P-III SVMP, both of which cause defibrin(ogen)ation. Thrombocytopenia, predominantly induced by a C-type lectin-like protein, and platelet hypoaggregation, caused by the two defibrin(ogen)ating enzymes, also contribute to hemostatic disturbances, which potentiate the systemic bleeding induced by hemorrhagic SVMPs. Cardiovascular disturbances leading to shock are due to the combined effects of hemorrhagic toxins, other venom components that increase vascular permeability, the action of hypotensive agents in the venom and of endogenous mediators, and the potential cardiotoxic effect of some toxins. Renal alterations are likely to be caused by direct cytotoxicity of venom components in the kidney, and by renal ischemia resultant from hypovolemia and hypoperfusion. Lethality induced by B. asper venom is the consequence of several combined effects among which the action of P-III SVMPs is especially relevant.Sweden-Central America NeTropicaUniversidad de Costa RicaInternational Foundation for Science (IFS)UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP