The Colombian scorpion Centruroides margaritatus produces a venom considered of low toxicity. Nev... more The Colombian scorpion Centruroides margaritatus produces a venom considered of low toxicity. Nevertheless, there are known cases of envenomation resulting in cardiovascular disorders, probably due to venom components that target ion channels. Among them, the humanether-à-go-go-Related gene (hERG1) potassium channels are critical for cardiac action potential repolarization and alteration in its functionality are associated with cardiac disorders. This work describes the purification and electrophysiological characterization of a Centruroides margaritatus venom component acting on hERG1 channels, the CmERG1 toxin. This novel peptide is composed of 42 amino acids with a MW of 4792.88 Da, folded by four disulfide bonds and it is classified as member number 10 of the γ-KTx1 toxin family. CmERG1 inhibits hERG1 currents with an IC50 of 3.4 ± 0.2 nM. Despite its 90.5% identity with toxin ɣ-KTx1.1, isolated from Centruroides noxius, CmERG1 completely blocks hERG1 current, suggesting a more ...
The present research and development work focuses on ophidism or ophidic accidentthat is a forgot... more The present research and development work focuses on ophidism or ophidic accidentthat is a forgotten public health problem, which is normally focused on antiophidic serumapplication. Complications are sometimes caused by the patients; delay to go to amedical centre and the health professionals lacking knowledge of the ophidismtreatment. In this work, we design under canvas model a Massive Open Online Course(MOOC) on introduction to ophidic accident giving a new accessible, massive anddynamic training strategy. It is nourished by the students’ contribution; unlike traditionaltraining programmes. For this reason, it is intended to promote other forms of training onprevention and knowledge of the ophidic accident, which are priority activities in theColombian territory. To end, we highlight that there exist a considerable number ofunderestimated cases due to the inadequate registration of the notification forms.
In Colombia, Lachesis acrochorda causes 2-3% of all snake envenomations. The accidents promote a ... more In Colombia, Lachesis acrochorda causes 2-3% of all snake envenomations. The accidents promote a high mortality rate (90%) due to blood and cardiovascular complications. Here, the effects of the snake venom of L. acrochorda (SVLa) were analyzed on human blood cells and on cardiovascular parameters of rats. SVLa induced blood coagulation, as measured by the prothrombin time test, but did not reduce the cell viability of neutrophils and platelets evaluated by the 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl tetrazolium bromide (MTT) reduction assay and by the lactate dehydrogenase (LDH) enzyme assay. In fact, SVLa increased the absorbance in platelets subjected to the MTT assay. SVLa induced platelet aggregation whose magnitude was comparable to that of the positive control adenosine diphosphate (ADP), and occurred earlier with increasing SVLa concentration. Acetylsalicylic acid (ASA, a cyclooxygenase inhibitor) or clopidogrel (an ADP receptor blocker) inhibited the aggregating effect of ...
Among other scorpion species, Colombia has two genera of the Buthidae family Centruroides and Tit... more Among other scorpion species, Colombia has two genera of the Buthidae family Centruroides and Tityus, considered to be dangerous to humans. This research shares scientific knowledge aiming to a better understanding about the pathophysiological effects of such venoms. The venom of the three species: Centruroides margaritarus, Tityus pachyurus, and T. n. sp. aff. metuendus with biomedical interest were studied. An initial pre-glycemic sample was taken from ICR mice. They were later intraperitoneally inoculated with doses of 35% and 70% of LD50 of total venom. Poisoning signs were observed during a 6-h period to determine the level of scorpionism. After observation, a second glycemic sample was taken, and a histopathological evaluation of different organs was performed. This work revealed that all three venoms showed considerably notorious histopathological alterations in main organs such as heart and lungs; and inducing multiple organ failure, in relation to the glycemia values, only ...
Background Bothrops asper represents the clinically most important snake species in Central Ameri... more Background Bothrops asper represents the clinically most important snake species in Central America and Northern South America, where it is responsible for an estimated 50–80% of snakebites. Compositional variability among the venom proteomes of B. asper lineages across its wide range mirrors clinical differences in their envenomings. Bothropic antivenoms generated in a number of Latin American countries commonly exhibit a certain degree of paraspecific effectiveness in the neutralization of congeneric venoms. Defining the phylogeographic boundaries of an antivenom's effectivity has implications for optimizing its clinical use. However, the molecular bases and impact of venom compositions on the immune recognition and neutralization of the toxic activities of across geographically disparate populations of B. asper lineages has not been comprehensively studied. Methodology/Principal findings Third-generation antivenomics was applied to quantify the cross-immunorecognizing capacit...
Introducción. El ofidismo es un relevante problema de salud pública y, en Colombia, se incluyó co... more Introducción. El ofidismo es un relevante problema de salud pública y, en Colombia, se incluyó como un evento de notificación obligatoria desde el año 2004. Por ser un país tropical con gran diversidad ecosistémica, ocupa el tercer puesto en Latinoamérica, después de México y Brasil, en presentar el mayor número de accidentes ofídicos.Objetivo. Realizar un análisis retrospectivo del accidente ofídico en el departamento de Nariño, con base en los eventos notificados entre los años 2008 y 2017 al Instituto Departamental de Salud de Nariño y al Sistema de Vigilancia en Salud Pública de Colombia.Materiales y métodos. Se hizo un análisis de tipo descriptivo y retrospectivo a partir de la recopilación e interpretación de la información consignada en las fichas de notificación para accidente ofídico del Instituto Departamental de Salud de Nariño, entre los años 2008 y 2017. Se representó la frecuencia del accidente ofídico a nivel municipal mediante la elaboración de un mapa y se identific...
Background: Scorpion venom causes renal injury and affect vascular ion-channels function. Centrur... more Background: Scorpion venom causes renal injury and affect vascular ion-channels function. Centruroides margaritatus scorpion is found in Colombia and is frequently the cause of envenomation accidents; however, its renal impact has never been investigated. Objective: To evaluate the effects of C. margaritatus venom (CmV) on renal parameters using isolated rat kidney and renal cell culture models. Method: Wistar rats (n = 5, weighing 240-300 g) were first perfused with Krebs-Henseleit solution containing 6 g 100 mL-1 bovine serum albumin. After 30 minutes, the kidneys were perfused with CmV to a final concentration of 10 μgmL-1; evaluation was performed by measuring perfusion pressure (PP), renal vascular resistance (RVR), urinary flow (UF), glomerular filtration rate (GFR), and percentage of electrolyte tubular transport. Moreover, kidney histological analyses and cell cytotoxicity in renal tubule epithelial cells (MDCK) and proximal tubular cells (LLC-MK2) were assessed. Results: Cm...
In efforts to find new antimicrobial peptides (AMPs), we studied the skin secretion of the endemi... more In efforts to find new antimicrobial peptides (AMPs), we studied the skin secretion of the endemic Colombian frog Dendropsophus columbianus belonging to a genus that has not been investigated previously. From HPLC-fractionated secretion, we identified one peptide with slightly antibacterial activity. Its peptide sequence showed no sequence similarity to current annotated peptides. We named this novel peptide dendropsophin 1 (Dc1). Afterward, two analogues were designed (Dc1.1 and Dc1.2) to improve the cationic and amphipathic features. Then, their antiproliferative and cytotoxic properties were evaluated against several pathogens including bacteria, fungi, protozoa and also mammalian cells. Dc1 and its two analogues exhibited moderate antibacterial activities and no hemolytic and cytotoxic effects on mammalian cells. Analogue Dc1.2 showed slightly improved antibacterial properties. Their secondary structures were characterised using CD spectroscopy and Dc1.2 displayed a higher α-hel...
Antimicrobial peptides (AMPs) represent a large and ubiquitous group of peptides. The current cri... more Antimicrobial peptides (AMPs) represent a large and ubiquitous group of peptides. The current crisis in antibiotic therapy has led to an intensified search for new antimicrobial agents. In this regard, scorpion venom constitutes a rich source of biologically active peptides including AMPs. In the present study, the purification of a novel peptide with antimicrobial activity against the Gram-negative bacteria Klebsiella pneumoniae is described. This antimicrobial peptide, named Cm38, was purified from Centruroides margaritatus scorpion venom using a two-step chromatographic strategy using C8 and C18 columns. This toxin inhibits the proliferation of the Gram-negative bacteria Klebsiella pneumoniae with a Minimal Inhibitory Concentration (MIC) of 64 μM. An analysis of the N-terminal sequence of Cm38 revealed a close structural relationship to Cn11, a Na+-channel modulator toxin previously isolated from Centruroides noxius scorpion venom. Therefore, to test Cm38 for effects on ion channels, we measured its effects on action potential firing in cultured dorsal root ganglion neurons. Cm38 depolarized and increased action potential firing in a subset of neurons tested. The present work reports a new peptide related to Cn11 with antimicrobial properties that is also active in neurons.
ABSTRACT Scorpionism is the disease caused in human beings by a scorpion sting. Depending on the ... more ABSTRACT Scorpionism is the disease caused in human beings by a scorpion sting. Depending on the severity of the sting, it can produce multiorgan system failure and death and is a public health problem worldwide with a high incidence and varying degrees of severity. But that in Colombia is a neglected health problem. The lack of awareness of the risks connected with scorpion accidents in Colombia has brought as a consequence the underestimation of this type of accident from the person who suffers it to the health professionals themselves. This too is worryingly reflected in the forming of mistaken diagnoses, in the administering of inadequate therapeutic measures, and in the lack of government programs aimed at preventing it. The systemic clinical symptoms associated with the envenomation caused by Colombian scorpions have been observed in some experimental studies, reports, series of cases, and observational studies and are related to processes of neurotoxicity, characterized by hyperactivity and intense and persistent depolarization of the autonomic fibers with the consequent massive release of neurotransmitters. These elements have been described previously for other species of scorpion of medical importance worldwide, such as Leiurus quinquestriatus, Androctonus australis, Tityus serrulatus, T. discrepans, and Centruroides exilicauda, among others. Severe scorpionism in Colombia is caused not only by T. pachyurus but also by seven species C. edwardsii, C. margaritatus, T. asthenes, T. forcipula, T. fuhrmanni, T. pachyurus, and T. n. sp. aff. metuendus, and the scorpion T. columbianus is ranked as a dangerous species.
Bothrops ayerbei, a pitviper inhabiting the Patía River&a... more Bothrops ayerbei, a pitviper inhabiting the Patía River's basin (Valle Alto del Río Patía) in the Southwestern Department of Cauca, Colombia, was considered as a variant form of Bothrops asper prior to being proposed as a new species in 2010, on the basis of subtle morphological differences. This study reports the proteomic and functional profiling of B. ayerbei venom. Its most striking feature is an almost complete absence (0.7%) of phospholipases A2 (PLA2), which is in contrast to the high proportion of these enzymes (25.3%) in the venom of B. asper from Cauca, as well as in other species of Bothrops. The predominant proteins in B. ayerbei venom are metalloproteinases (53.7%), in agreement with its higher hemorrhagic and lethal activities compared to B. asper venom. Moreover, the negligible content of PLA2s in B. ayerbei venom correlates with its weaker myotoxic effect, in contrast to B. asper venom, here shown to contain abundant Asp49- and Lys49-type PLA2s responsible for its strong myotoxic activity. Other components identified in B. ayerbei venom include bradykinin-potentiating-like peptides and proteins belonging to the C-type lectin/lectin-like, serine proteinase, l-amino acid oxidase, disintegrin, cysteine-rich secretory protein, nerve growth factor, and phosphodiesterase families. The venom composition of B. ayerbei resembles that of neonate specimens of B. asper, which shows a predominance of metalloproteinases, with only low amounts of PLA2s. Therefore, the present findings suggest that the expression of venom proteins in B. ayerbei, in contrast to B. asper, might retain a marked…
The Colombian scorpion Centruroides margaritatus produces a venom considered of low toxicity. Nev... more The Colombian scorpion Centruroides margaritatus produces a venom considered of low toxicity. Nevertheless, there are known cases of envenomation resulting in cardiovascular disorders, probably due to venom components that target ion channels. Among them, the humanether-à-go-go-Related gene (hERG1) potassium channels are critical for cardiac action potential repolarization and alteration in its functionality are associated with cardiac disorders. This work describes the purification and electrophysiological characterization of a Centruroides margaritatus venom component acting on hERG1 channels, the CmERG1 toxin. This novel peptide is composed of 42 amino acids with a MW of 4792.88 Da, folded by four disulfide bonds and it is classified as member number 10 of the γ-KTx1 toxin family. CmERG1 inhibits hERG1 currents with an IC50 of 3.4 ± 0.2 nM. Despite its 90.5% identity with toxin ɣ-KTx1.1, isolated from Centruroides noxius, CmERG1 completely blocks hERG1 current, suggesting a more ...
The present research and development work focuses on ophidism or ophidic accidentthat is a forgot... more The present research and development work focuses on ophidism or ophidic accidentthat is a forgotten public health problem, which is normally focused on antiophidic serumapplication. Complications are sometimes caused by the patients; delay to go to amedical centre and the health professionals lacking knowledge of the ophidismtreatment. In this work, we design under canvas model a Massive Open Online Course(MOOC) on introduction to ophidic accident giving a new accessible, massive anddynamic training strategy. It is nourished by the students’ contribution; unlike traditionaltraining programmes. For this reason, it is intended to promote other forms of training onprevention and knowledge of the ophidic accident, which are priority activities in theColombian territory. To end, we highlight that there exist a considerable number ofunderestimated cases due to the inadequate registration of the notification forms.
In Colombia, Lachesis acrochorda causes 2-3% of all snake envenomations. The accidents promote a ... more In Colombia, Lachesis acrochorda causes 2-3% of all snake envenomations. The accidents promote a high mortality rate (90%) due to blood and cardiovascular complications. Here, the effects of the snake venom of L. acrochorda (SVLa) were analyzed on human blood cells and on cardiovascular parameters of rats. SVLa induced blood coagulation, as measured by the prothrombin time test, but did not reduce the cell viability of neutrophils and platelets evaluated by the 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl tetrazolium bromide (MTT) reduction assay and by the lactate dehydrogenase (LDH) enzyme assay. In fact, SVLa increased the absorbance in platelets subjected to the MTT assay. SVLa induced platelet aggregation whose magnitude was comparable to that of the positive control adenosine diphosphate (ADP), and occurred earlier with increasing SVLa concentration. Acetylsalicylic acid (ASA, a cyclooxygenase inhibitor) or clopidogrel (an ADP receptor blocker) inhibited the aggregating effect of ...
Among other scorpion species, Colombia has two genera of the Buthidae family Centruroides and Tit... more Among other scorpion species, Colombia has two genera of the Buthidae family Centruroides and Tityus, considered to be dangerous to humans. This research shares scientific knowledge aiming to a better understanding about the pathophysiological effects of such venoms. The venom of the three species: Centruroides margaritarus, Tityus pachyurus, and T. n. sp. aff. metuendus with biomedical interest were studied. An initial pre-glycemic sample was taken from ICR mice. They were later intraperitoneally inoculated with doses of 35% and 70% of LD50 of total venom. Poisoning signs were observed during a 6-h period to determine the level of scorpionism. After observation, a second glycemic sample was taken, and a histopathological evaluation of different organs was performed. This work revealed that all three venoms showed considerably notorious histopathological alterations in main organs such as heart and lungs; and inducing multiple organ failure, in relation to the glycemia values, only ...
Background Bothrops asper represents the clinically most important snake species in Central Ameri... more Background Bothrops asper represents the clinically most important snake species in Central America and Northern South America, where it is responsible for an estimated 50–80% of snakebites. Compositional variability among the venom proteomes of B. asper lineages across its wide range mirrors clinical differences in their envenomings. Bothropic antivenoms generated in a number of Latin American countries commonly exhibit a certain degree of paraspecific effectiveness in the neutralization of congeneric venoms. Defining the phylogeographic boundaries of an antivenom's effectivity has implications for optimizing its clinical use. However, the molecular bases and impact of venom compositions on the immune recognition and neutralization of the toxic activities of across geographically disparate populations of B. asper lineages has not been comprehensively studied. Methodology/Principal findings Third-generation antivenomics was applied to quantify the cross-immunorecognizing capacit...
Introducción. El ofidismo es un relevante problema de salud pública y, en Colombia, se incluyó co... more Introducción. El ofidismo es un relevante problema de salud pública y, en Colombia, se incluyó como un evento de notificación obligatoria desde el año 2004. Por ser un país tropical con gran diversidad ecosistémica, ocupa el tercer puesto en Latinoamérica, después de México y Brasil, en presentar el mayor número de accidentes ofídicos.Objetivo. Realizar un análisis retrospectivo del accidente ofídico en el departamento de Nariño, con base en los eventos notificados entre los años 2008 y 2017 al Instituto Departamental de Salud de Nariño y al Sistema de Vigilancia en Salud Pública de Colombia.Materiales y métodos. Se hizo un análisis de tipo descriptivo y retrospectivo a partir de la recopilación e interpretación de la información consignada en las fichas de notificación para accidente ofídico del Instituto Departamental de Salud de Nariño, entre los años 2008 y 2017. Se representó la frecuencia del accidente ofídico a nivel municipal mediante la elaboración de un mapa y se identific...
Background: Scorpion venom causes renal injury and affect vascular ion-channels function. Centrur... more Background: Scorpion venom causes renal injury and affect vascular ion-channels function. Centruroides margaritatus scorpion is found in Colombia and is frequently the cause of envenomation accidents; however, its renal impact has never been investigated. Objective: To evaluate the effects of C. margaritatus venom (CmV) on renal parameters using isolated rat kidney and renal cell culture models. Method: Wistar rats (n = 5, weighing 240-300 g) were first perfused with Krebs-Henseleit solution containing 6 g 100 mL-1 bovine serum albumin. After 30 minutes, the kidneys were perfused with CmV to a final concentration of 10 μgmL-1; evaluation was performed by measuring perfusion pressure (PP), renal vascular resistance (RVR), urinary flow (UF), glomerular filtration rate (GFR), and percentage of electrolyte tubular transport. Moreover, kidney histological analyses and cell cytotoxicity in renal tubule epithelial cells (MDCK) and proximal tubular cells (LLC-MK2) were assessed. Results: Cm...
In efforts to find new antimicrobial peptides (AMPs), we studied the skin secretion of the endemi... more In efforts to find new antimicrobial peptides (AMPs), we studied the skin secretion of the endemic Colombian frog Dendropsophus columbianus belonging to a genus that has not been investigated previously. From HPLC-fractionated secretion, we identified one peptide with slightly antibacterial activity. Its peptide sequence showed no sequence similarity to current annotated peptides. We named this novel peptide dendropsophin 1 (Dc1). Afterward, two analogues were designed (Dc1.1 and Dc1.2) to improve the cationic and amphipathic features. Then, their antiproliferative and cytotoxic properties were evaluated against several pathogens including bacteria, fungi, protozoa and also mammalian cells. Dc1 and its two analogues exhibited moderate antibacterial activities and no hemolytic and cytotoxic effects on mammalian cells. Analogue Dc1.2 showed slightly improved antibacterial properties. Their secondary structures were characterised using CD spectroscopy and Dc1.2 displayed a higher α-hel...
Antimicrobial peptides (AMPs) represent a large and ubiquitous group of peptides. The current cri... more Antimicrobial peptides (AMPs) represent a large and ubiquitous group of peptides. The current crisis in antibiotic therapy has led to an intensified search for new antimicrobial agents. In this regard, scorpion venom constitutes a rich source of biologically active peptides including AMPs. In the present study, the purification of a novel peptide with antimicrobial activity against the Gram-negative bacteria Klebsiella pneumoniae is described. This antimicrobial peptide, named Cm38, was purified from Centruroides margaritatus scorpion venom using a two-step chromatographic strategy using C8 and C18 columns. This toxin inhibits the proliferation of the Gram-negative bacteria Klebsiella pneumoniae with a Minimal Inhibitory Concentration (MIC) of 64 μM. An analysis of the N-terminal sequence of Cm38 revealed a close structural relationship to Cn11, a Na+-channel modulator toxin previously isolated from Centruroides noxius scorpion venom. Therefore, to test Cm38 for effects on ion channels, we measured its effects on action potential firing in cultured dorsal root ganglion neurons. Cm38 depolarized and increased action potential firing in a subset of neurons tested. The present work reports a new peptide related to Cn11 with antimicrobial properties that is also active in neurons.
ABSTRACT Scorpionism is the disease caused in human beings by a scorpion sting. Depending on the ... more ABSTRACT Scorpionism is the disease caused in human beings by a scorpion sting. Depending on the severity of the sting, it can produce multiorgan system failure and death and is a public health problem worldwide with a high incidence and varying degrees of severity. But that in Colombia is a neglected health problem. The lack of awareness of the risks connected with scorpion accidents in Colombia has brought as a consequence the underestimation of this type of accident from the person who suffers it to the health professionals themselves. This too is worryingly reflected in the forming of mistaken diagnoses, in the administering of inadequate therapeutic measures, and in the lack of government programs aimed at preventing it. The systemic clinical symptoms associated with the envenomation caused by Colombian scorpions have been observed in some experimental studies, reports, series of cases, and observational studies and are related to processes of neurotoxicity, characterized by hyperactivity and intense and persistent depolarization of the autonomic fibers with the consequent massive release of neurotransmitters. These elements have been described previously for other species of scorpion of medical importance worldwide, such as Leiurus quinquestriatus, Androctonus australis, Tityus serrulatus, T. discrepans, and Centruroides exilicauda, among others. Severe scorpionism in Colombia is caused not only by T. pachyurus but also by seven species C. edwardsii, C. margaritatus, T. asthenes, T. forcipula, T. fuhrmanni, T. pachyurus, and T. n. sp. aff. metuendus, and the scorpion T. columbianus is ranked as a dangerous species.
Bothrops ayerbei, a pitviper inhabiting the Patía River&a... more Bothrops ayerbei, a pitviper inhabiting the Patía River's basin (Valle Alto del Río Patía) in the Southwestern Department of Cauca, Colombia, was considered as a variant form of Bothrops asper prior to being proposed as a new species in 2010, on the basis of subtle morphological differences. This study reports the proteomic and functional profiling of B. ayerbei venom. Its most striking feature is an almost complete absence (0.7%) of phospholipases A2 (PLA2), which is in contrast to the high proportion of these enzymes (25.3%) in the venom of B. asper from Cauca, as well as in other species of Bothrops. The predominant proteins in B. ayerbei venom are metalloproteinases (53.7%), in agreement with its higher hemorrhagic and lethal activities compared to B. asper venom. Moreover, the negligible content of PLA2s in B. ayerbei venom correlates with its weaker myotoxic effect, in contrast to B. asper venom, here shown to contain abundant Asp49- and Lys49-type PLA2s responsible for its strong myotoxic activity. Other components identified in B. ayerbei venom include bradykinin-potentiating-like peptides and proteins belonging to the C-type lectin/lectin-like, serine proteinase, l-amino acid oxidase, disintegrin, cysteine-rich secretory protein, nerve growth factor, and phosphodiesterase families. The venom composition of B. ayerbei resembles that of neonate specimens of B. asper, which shows a predominance of metalloproteinases, with only low amounts of PLA2s. Therefore, the present findings suggest that the expression of venom proteins in B. ayerbei, in contrast to B. asper, might retain a marked…
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Papers by Jimmy Alexander Guerrero Vargas