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1.
Purinergic Signal ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958820

RESUMO

Snake bites are a severe problem in the countryside of Brazil and are usually attributed to snakes of the genera Bothrops, Crotalus, and Lachesis. Snake venom can release ectoenzymes and nucleotidases that modulate the purinergic system. In addition to serum therapy against snake poisoning, medicinal plants with anti-inflammatory activities, such as Tabebuia aurea, is empirically applied in accidents that occur in difficult-to-access areas. This study aimed was to verify the presence and activity of nucleotidases in the crude venom of Bothrops mattogrossensis (BmtV) in vitro and characterize the modulation of purinergic components, myeloid differentiation, and inflammatory/oxidative stress markers by BmtV in vivo and in vitro. Moreover, our study assessed the inhibitory activities of specioside, an iridoid isolated from Tabebuia aurea, against the effects of BmtV. Proteomic analysis of venom content and nucleotidase activity confirm the presence of ectonucleotidase-like enzymes in BmtV. In in vivo experiments, BmtV altered purinergic component expression (P2X7 receptor, CD39 and CD73), increased neutrophil numbers in peripheral blood, and elevated oxidative stress/inflammatory parameters such as lipid peroxidation and myeloperoxidase activity. BmtV also decreased viability and increased spreading index and phagocytic activity on macrophages. Specioside inhibited nucleotidase activity, restored neutrophil numbers, and mediate the oxidative/inflammatory effects produced by BmtV. We highlight the effects produced by BmtV in purinergic system components, myeloid differentiation, and inflammatory/oxidative stress parameters, while specioside reduced the main BmtV-dependent effects.

2.
Vet Parasitol Reg Stud Reports ; 53: 101060, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39025553

RESUMO

Snakes of the genus Bothrops inhabit tropical forests in Central and South America and are important for the biomedical and pharmaceutical industries because of the chemical properties of their venom. They serve as either definitive or intermediate hosts for many parasitic helminths. The Marajó Island (Brazil) is the natural habitat of venomous snakes, Bothrops atrox and Bothrops marajoensis, which are often found around rural and peri-urban areas and are known to bite humans. Samples of helminths parasitizing the oral cavity, subcutaneous tissues, coelomic cavity, and intestine of four B. atrox from Marajó Island (Pará-Brazil) were collected. The specimens studied were taxonomically classified as trematodes of the species Stycholecitha serpentis, nematodes of the genera Eustrongylides and Camallanus and cystacanths of an acanthocephalan of the genus Centrorhynchus. The aims of the present study were: to record helminths found in B. atrox from the Marajó Island; to discuss their role as definitive, intermediate, or paratenic hosts; and to compile a list of helminths that have been recorded in snakes of the genus Bothrops of the Neotropical region.


Assuntos
Bothrops , Helmintíase Animal , Animais , Bothrops/parasitologia , Brasil/epidemiologia , Helmintíase Animal/parasitologia , Helmintíase Animal/epidemiologia , Masculino , Helmintos/classificação , Helmintos/isolamento & purificação , Feminino , Bothrops atrox
3.
Toxicon ; 247: 107793, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-38838861

RESUMO

Bothrops atrox envenomations in the Brazilian Amazon are responsible for a number of local and systemic effects. Among these, stroke presents the worst prognosis for the patient since it may evolve into disabilities and/or premature death. This complication is caused by coagulation disorders and generates hemorrhagic and thrombotic conditions. This study presents a case report of a 54-year-old female patient who presented extensive cerebral ischemia after a B. atrox envenomation that occurred in the state of Amazonas, Brazil. The patient was hospitalized for 102 days, which included a stay in the intensive care unit. Clinical and laboratory findings indicated a thrombogenic coagulopathy. On discharge, the patient had no verbal response, partial motor response, and right hemiplegia. The assessment carried out four years after discharge evidenced incapacitation, global aphasia and bilateral lower and upper limbs showed hypotrophy with a global decrease in strength. Ischemic stroke is a possible complication of B. atrox snakebites even after antivenom treatment, with the potential to cause debilitating long-term consequences.


Assuntos
Antivenenos , Bothrops , Mordeduras de Serpentes , Mordeduras de Serpentes/complicações , Feminino , Pessoa de Meia-Idade , Animais , Humanos , Brasil , Antivenenos/uso terapêutico , AVC Isquêmico/etiologia , Venenos de Crotalídeos/toxicidade , Venenos de Crotalídeos/intoxicação , Isquemia Encefálica/etiologia , Bothrops atrox
4.
Int Immunopharmacol ; 134: 112215, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38744173

RESUMO

Camelid single-domain antibodies (VHH) represent a promising class of immunobiologicals for therapeutic applications due to their remarkable stability, specificity, and therapeutic potential. To enhance the effectiveness of antivenoms for snakebites, various methods have been explored to address limitations associated with serum therapy, particularly focusing on mitigating local damage and ensuring sustainable production. Our study aimed to characterize the pharmacological profile and neutralization capacity of anti-Phospholipase A2 (PLA2) monomeric VHH (Genbank accessions: KC329718). Using a post-envenoming mouse model, we used intravital microscopy to assess leukocyte influx, measured CK and LDH levels, and conducted a histopathology analysis to evaluate VHH KC329718's ability to neutralize myotoxic activity. Our findings demonstrated that VHH KC329718 exhibited heterogeneous distribution in muscle tissue. Treatment with VHH KC329718 reduced leukocyte influx caused by BthTX-I (a Lys-49 PLA2) by 28 %, as observed through intravital microscopy. When administered at a 1:10 ratio [venom or toxin:VHH (w/w)], VHH KC329718 significantly decreased myotoxicity, resulting in a 35-40 % reduction in CK levels from BthTX-I and BthTX-II (an Asp-49 PLA2) and a 60 % decrease in CK levels from B. jararacussu venom. LDH levels also showed reductions of 60%, 80%, and 60% induced by BthTX-I, BthTX-II, and B. jararacussu venom, respectively. Histological analysis confirmed the neutralization potential, displaying a significant reduction in tissue damage and inflammatory cell count in mice treated with VHH KC329718 post B. jararacussu venom inoculation. This study underscores the potential of monomeric anti-PLA2 VHH in mitigating myotoxic effects, suggesting a promising avenue for the development of new generation antivenoms to address current therapeutic limitations.


Assuntos
Antivenenos , Bothrops , Fosfolipases A2 , Anticorpos de Domínio Único , Mordeduras de Serpentes , Animais , Anticorpos de Domínio Único/imunologia , Mordeduras de Serpentes/tratamento farmacológico , Mordeduras de Serpentes/imunologia , Antivenenos/farmacologia , Antivenenos/uso terapêutico , Camundongos , Fosfolipases A2/metabolismo , Venenos de Crotalídeos/imunologia , Venenos de Crotalídeos/toxicidade , Masculino , Modelos Animais de Doenças , Músculo Esquelético/patologia , Músculo Esquelético/efeitos dos fármacos , Leucócitos/efeitos dos fármacos , Leucócitos/imunologia , Humanos , Creatina Quinase/sangue
5.
J Ethnopharmacol ; 332: 118349, 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-38762214

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Snakebite envenomation (SBE) is the world's most lethal neglected tropical disease. Bothrops jararaca is the species that causes the greatest number of SBEs in the South and Southeastern of Brazil. The main symptoms are local (inflammation, edema, hemorrhage, and myonecrosis) and systemic (hemorrhage, hemostatic alterations with consumptive coagulopathy, and death) effects. Species of the genus Siparuna, Siparunaceae, are used in folk and traditional medicine to treat SBE. However, limited information is available concerning Brazilian Siparuna species against SBE. AIM OF THE STUDY: To investigate the correlation between the compounds present in the extracts of five Siparuna species as potential agents against proteolytic activity, plasma coagulation, and phospholipase A2 (PLA2) activity caused by B. jararaca venom, using data obtained by UHPLC-MS/MS, biological activity, and multivariate statistics. MATERIALS AND METHODS: The ethanol extracts from leaves of S. ficoides, S. decipiens, S. glycycarpa, S. reginae, and S. cymosa were fractionated by liquid-liquid extraction using different solvents of increasing polarity (hexane, dichloromethane, ethyl acetate, and n-butanol), affording their respective extracts, totaling 25 samples that were assayed through in vitro plasma coagulation and proteolytic activity assays. Moreover, the extracts were analyzed by UHPLC-MS/MS, using electrospray ionization (ESI) and atmospheric-pressure chemical ionization (APCI) in negative and positive ionization modes. The data was processed in MZmine v. 2.53 and evaluated by multivariate statistical tests (PLS) using the software UnscramblerX v. 10.4. These data were also used to build molecular networks (GNPS), and some ions of interest could be annotated using the library of molecules on the GNPS platform. RESULTS: A total of 19 extracts inhibited B. jararaca-induced plasma coagulation, with emphasis on S. cymosa and S. reginae (800 s). The inhibition of the proteolytic activity was also promising, ranging from 16% (S. glycycarpa) to 99% (S. cymosa, S. decipiens, and S. reginae). In addition, most extracts from S. cymosa and S. reginae inhibited 70-90% of PLA2 activity. Based on data from positive mode APCI analyses, it was possible to obtain a statistic model with reliable predictive capacity which exhibited an average R2 of 0.95 and a Q2 of 0.88, indicating a robust fit. This process revealed five ions, identified as the alkaloids: coclaurine (1), stepholidine (2) O-methylisopiline (3), nornantenine (4) and laurolitsine (5). This is the first study to evidence the potential antivenom of alkaloids from Siparuna species. CONCLUSIONS: Altogether, our results give support to the popular use of Siparuna extracts in SBE accidents, suggesting their potential as an alternative or complementary strategy against envenoming by B. jararaca venom. The predicted ions in the chemometric analysis for the assayed activities can also be correlated with the blocking activity and encourage the continuation of this study for possible isolation and testing of individual compounds on the used models.


Assuntos
Alcaloides , Coagulação Sanguínea , Bothrops , Venenos de Crotalídeos , Extratos Vegetais , Animais , Coagulação Sanguínea/efeitos dos fármacos , Venenos de Crotalídeos/toxicidade , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Alcaloides/farmacologia , Alcaloides/isolamento & purificação , Alcaloides/química , Brasil , Proteólise/efeitos dos fármacos , Fosfolipases A2/metabolismo , Inibidores de Fosfolipase A2/farmacologia , Inibidores de Fosfolipase A2/isolamento & purificação , Folhas de Planta/química , Antivenenos/farmacologia , Antivenenos/isolamento & purificação , Inibidores de Proteases/farmacologia , Inibidores de Proteases/isolamento & purificação , Espectrometria de Massas em Tandem , Bothrops jararaca
6.
Biomedicines ; 12(4)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38672090

RESUMO

In recent years, extensive research has delved into the pathophysiology of local reactions triggered by Bothrops snake venoms. Even though antivenom works well at reducing death and systemic effects, it is still not very effective in treating local reactions because it cannot counteract damage that has already been triggered. This limitation might be attributed to certain molecules that amplify the venom-induced innate response. While evidence suggests endogenous mediators at the venom site play a role in this envenomation, in Brazil, the concurrent use of anti-inflammatory agents or other drugs alongside antivenom remains uncommon. This study evaluated the pharmacological mediation of alterations in leukocyte-endothelium interactions following the experimental envenomation of mice with Bothrops jararaca venom, the main culprit of snake-related accidents in Southeast Brazil. We treated envenomed mice with inhibitors of different pharmacological pathways and observed the cremaster muscle microcirculation with intravital microscopy. We found that eicosanoids related to cyclooxygenase pathways and nitric oxide significantly contributed to B. jararaca venom-induced alterations in leukocyte-endothelium interactions. Conversely, lipoxygenase-mediated eicosanoids, histamine, and serotonin had minimal participation. Notably, dexamethasone and antivenom treatment diminished B. jararaca venom-induced alterations in leukocyte-endothelium interactions. The limited efficacy of the antivenom in managing Bothrops venom-induced local reactions emphasizes the critical need for supplementary treatments to enhance therapeutic outcomes.

7.
Toxins (Basel) ; 16(4)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38668613

RESUMO

BACKGROUND: Snakebite envenomation (SBE) causes diverse toxic effects in humans, including disability and death. Current antivenom therapies effectively prevent death but fail to block local tissue damage, leading to an increase in the severity of envenomation; thus, seeking alternative treatments is crucial. METHODS: This study analyzed the potential of two fucoidan sulfated polysaccharides extracted from brown seaweeds Fucus vesiculosus (FVF) and Undaria pinnatifida (UPF) against the fibrinogen or plasma coagulation, proteolytic, and phospholipase A2 (PLA2) activities of Bothrops jararaca, B. jararacussu, and B. neuwiedi venom. The toxicity of FVF and UPF was assessed by the hemocompatibility test. RESULTS: FVF and UPF did not lyse human red blood cells. FVF and UPF inhibited the proteolytic activity of Bothrops jararaca, B. jararacussu, and B. neuwiedi venom by approximately 25%, 50%, and 75%, respectively, while all venoms led to a 20% inhibition of PLA2 activity. UPF and FVF delayed plasma coagulation caused by the venoms of B. jararaca and B. neuwiedi but did not affect the activity of B. jararacussu venom. FVF and UPF blocked the coagulation of fibrinogen induced by all these Bothropic venoms. CONCLUSION: FVF and UPF may be of importance as adjuvants for SBE caused by species of Bothrops, which are the most medically relevant snakebite incidents in South America, especially Brazil.


Assuntos
Coagulação Sanguínea , Venenos de Crotalídeos , Fucus , Fosfolipases A2 , Polissacarídeos , Undaria , Animais , Antivenenos/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Bothrops , Bothrops jararaca , Venenos de Crotalídeos/toxicidade , Venenos de Crotalídeos/enzimologia , Algas Comestíveis/química , Fucus/química , Fosfolipases A2/metabolismo , Polissacarídeos/farmacologia , Polissacarídeos/isolamento & purificação , Proteólise/efeitos dos fármacos , Alga Marinha/química , Undaria/química , Serpentes Peçonhentas
8.
Toxins (Basel) ; 16(4)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38668612

RESUMO

Accidents caused by Bothrops jararaca (Bj) snakes result in several local and systemic manifestations, with pain being a fundamental characteristic. The inflammatory process responsible for hyperalgesia induced by Bj venom (Bjv) has been studied; however, the specific roles played by the peripheral and central nervous systems in this phenomenon remain unclear. To clarify this, we induced hyperalgesia in rats using Bjv and collected tissues from dorsal root ganglia (DRGs) and spinal cord (SC) at 2 and 4 h post-induction. Samples were labeled for Iba-1 (macrophage and microglia), GFAP (satellite cells and astrocytes), EGR1 (neurons), and NK1 receptors. Additionally, we investigated the impact of minocycline, an inhibitor of microglia, and GR82334 antagonist on Bjv-induced hyperalgesia. Our findings reveal an increase in Iba1 in DRG at 2 h and EGR1 at 4 h. In the SC, markers for microglia, astrocytes, neurons, and NK1 receptors exhibited increased expression after 2 h, with EGR1 continuing to rise at 4 h. Minocycline and GR82334 inhibited venom-induced hyperalgesia, highlighting the crucial roles of microglia and NK1 receptors in this phenomenon. Our results suggest that the hyperalgesic effects of Bjv involve the participation of microglial and astrocytic cells, in addition to the activation of NK1 receptors.


Assuntos
Bothrops , Venenos de Crotalídeos , Gânglios Espinais , Hiperalgesia , Receptores da Neurocinina-1 , Animais , Hiperalgesia/induzido quimicamente , Hiperalgesia/metabolismo , Venenos de Crotalídeos/toxicidade , Masculino , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Receptores da Neurocinina-1/metabolismo , Minociclina/farmacologia , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Proteína 1 de Resposta de Crescimento Precoce/genética , Microglia/efeitos dos fármacos , Microglia/metabolismo , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Ratos , Proteína Glial Fibrilar Ácida/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Proteínas dos Microfilamentos/metabolismo , Antagonistas dos Receptores de Neurocinina-1/farmacologia , Ratos Sprague-Dawley
9.
Curr Med Chem ; 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38676530

RESUMO

The pursuit of novel treatment alternatives to address the accumulated resistance to antimicrobials over the years has prompted the scientific community to explore biodiversity, particularly animal venom, as a potential source of new antimicrobial drugs. Snake venoms, with their complex mixtures of components, are particularly promising targets for investigation in this regard. The search for novel molecules exhibiting antimicrobial activity against multidrug-resistant strains is of paramount importance for public health and numerous research groups worldwide. High expectations within the healthcare field are supported by the scientific literature, which highlights the potential development of innovative drugs through in vivo and in vitro application, depending on dose titration. Snake venoms and their molecules and peptides offer exponential possibilities for biotechnological applications as antimicrobial agents. However, many uncertainties and unexplored avenues remain, presenting opportunities for discoveries and research.

10.
Heliyon ; 10(5): e26768, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38434332

RESUMO

Background: Snake envenomation is a medical condition with high morbidity and mortality in southwestern Colombia. Objectives: To describe the characteristics of the envenomation caused by Viperidae snakes view in a highly complex hospital in Southwestern Colombia. Methods: A cross-sectional study was carried out. Patients treated for Viperidae snake envenomation from 2001 to 2020 in a Hospital Fundación Valle del Lili, Cali, Colombia, were studied. Results: Twenty-eight patients were included. Envenomation was caused by the genera Bothrops, Bothriechis, Porthidium, and Bothrocophias. The median age was 37.7 (±20.6), and they were predominantly male (19, 68%). Bites occurred on the upper extremities in 16 (57%) patients. Pain (23, 81%) and edema (22, 78%) were the most common clinical symptoms. Thirteen (46%) patients presented coagulopathy. Prolonged prothrombin and activated partial thromboplastin times were common: (22, 78% and 15, 53%, respectively). Twenty (71%) patients were treated with polyvalent antivenom (median dose of 6 (2-15) vials). The median time between the accident and antivenom administration was 9 h (5.5-17). Door-to-needle time was 37.5 (0-62) min. Eighteen (64%) patients were admitted to the intensive care unit. Three (11%) patients had serum sickness. Seven (25%) developed infectious complications, four (14%) had surgery, one (3%) had compartment syndrome, one (3%) underwent amputation of the affected limb, and one (3%) patient died. Conclusions: Local manifestations and coagulopathy were common clinical features. Polyvalent antivenom was an effective treatment for disease control. Significant complications were associated with delays in seeking medical care.

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