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Cancer is the transformation of healthy cells into tumor cells in a multistage process that can affect any organ of the body. This disease is the second leading cause of death globally. There are now more than 10 million cancer cases per year worldwide, and the most common occurs in the lung, breast, and colon. Several studies demonstrate that lifestyle and eating habits are directly related to tumor cells’ appearance, such as high body mass index, low fruit and vegetable intake, lack of physical activity, and tobacco and alcohol use. It is widely believed that diet and nutrients can act as cancer risk-modifiers throughout the process of carcinogenesis, including initiation, promotion, progression, and/or conversion. Different plants have been the source of therapeutic agents. Plant-derived compounds have become indispensable for modern pharmacotherapy, and phenolic compounds are one of the most investigated due to their antitumor activity. Their cellular targets and mechanisms are compiled in the present work. Phenolic compounds are secondary metabolites present in large quantities in medicinal herbs and dietary plants (e.g., fruits, vegetables, and spices). They possess a diverse range of beneficial biological activities, which contribute to their potent effects on inhibiting carcinogenesis. Some benefits include cell proliferation and angiogenesis inhibition and anti-inflammatory, antioxidant, and antimetastatic activities. Thus, the present review supports the recommendations for consuming foods and drinks rich in phenolic compounds to prevent and possibly treat cancer.

Herbal medicines represent an advantageous alternative for the prevention and treatment of several diseases when compared to allopathic medicines. Averrhoa carambola (Oxalidaceae) is a plant rich in phenolic compounds and popularly known for its medicinal properties such as anti-inflammatory, antioxidant, and hypoglycemic. Different enzymes of the human organism participate in physiological processes which involve hemostasis, inflammation, and formation of new tissue. These enzymes are highlighted as pharmaceutical targets for the treatment of numerous pathologies. The present work evaluated the aqueous and ethanolic extracts from A. carambola leaves on phospholipase, hemolytic, caseinolytic, thrombolytic, coagulant, and fibrinogenolytic activities induced by phospholipases A2 and proteases. Phenolic compounds and total flavonoids were quantified in the aqueous and ethanolic extracts of the leaves of Averrhoa carambola. These extracts were evaluated, in vitro, on phospholipase, proteolytic, hemolytic, thrombolytic and fibrinogenolytic activities induced by snake venoms. The results confirm the pharmacological potential of A. carambola since the extracts were able to modulate all evaluated activities related to hemostasis through inhibitions or potentiation of the enzymatic activities (phospholipases A2 and proteases). The constituents of A. carambola may act interfering in processes such as coagulation, thrombus dissolution, and fibrinogenolysis., Os medicamentos fitoterápicos representam uma alternativa vantajosa para a prevenção e tratamento de diversas doenças quando comparados aos medicamentos alopáticos. Averrhoa carambola (Oxalidaceae) é uma planta rica em compostos fenólicos e popularmente conhecida por suas propriedades medicinais como anti-inflamatória, antioxidante e hipoglicêmica. Diferentes enzimas do organismo humano participam de processos fisiológicos que envolvem hemostasia, inflamação e formação de novos tecidos. Essas enzimas são destacadas como alvos farmacêuticos para o tratamento de inúmeras patologias. O presente trabalho avaliou os extratos aquoso e etanólico das folhas de A. carambola sobre as atividades fosfolipásica, hemolítica, caseinolítica, trombolítica, coagulante e fibrinogenolítica induzidas por fosfolipases A2 e proteases. Compostos fenólicos e flavonoides totais foram quantificados nos extratos aquoso e etanólico das folhas de A. carambola. Esses extratos foram avaliados, in vitro, sobre as atividades fosfolipásica, proteolítica, hemolítica, trombolítica e fibrinogenolítica induzidas por peçonhas de serpentes. Os resultados confirmam o potencial farmacológico de A. carambola uma vez que os extratos foram capazes de modular todas as atividades avaliadas relacionadas à hemostasia por meio de inibições ou potencialização das atividades enzimáticas (fosfolipases A2 e proteases). Os constituintes de A. carambola podem atuar interferindo em processos como coagulação, dissolução de trombos e fibrinogenólise.

Enzymatic inhibition by natural compounds may represent a valuable adjuvant in snakebite serum therapy. The objective in this work was to evaluate possible in vitro interactions between vanillic acid and enzymes from Bothrops spp. and Crotalus durissus terrificus venoms, and also suggest a theory as how they interact based on molecular docking. Vanillic acid inhibited the phospholipase activity induced by Bothrops alternatus (∼25% inhibition); the caseinolytic activity induced by Bothrops atrox (∼30%), Bothrops jararacussu (∼44%), and C. d. terrificus (∼33%); the fibrinogenolysis induced by B. jararacussu, B. atrox, and C. d. terrificus (100%); the serine protease activity induced by Bothrops moojeni (∼45%) and Bothrops jararaca (∼66%); the hemolytic activity induced by B. moojeni (∼26%); the thrombolysis activity induced by B. atrox (∼30%) and B. jararacussu (∼20%); and the thrombotic activity induced by C. d. terrificus (∼8%). The compound was also capable of delaying the coagulation time in citrated plasma by 60, 35, and 75 Sec, when incubated with B. moojeni, B. atrox, and B. jararaca, respectively. The results obtained expand the possibilities for future pharmaceutical use of vanillic acid, considering the high homology degree among human and snake venom phospholipases A2 and proteases (involved in chronic inflammatory diseases). Also, this compound can be used as adjuvant to improve currently available treatments for ophidism victims.

Background Proteases and phospholipases A2 are involved in processes related to hemostasis. Medicinal plants which contain bioactive phytochemicals, can act as enzymatic modulators. Method In this study, the chemical composition and pharmacological potential exerted by the aqueous and ethanolic extracts of Averrhoa carambola L. fruits were evaluated on the activity of phospholipases and proteases present in the Bothrops, Crotalus durissus terrificus (C.d.t.), and Lachesis muta snake venoms. Results: In the extracts were identified phenolic compounds, which are possibly responsible for the inhibition of the phospholipase (20–50%), hemolytic, and fibrinogenolytic (up to 100%) activities. The aqueous extract presented a pro-coagulant activity on the C.d.t. venom and anti-coagulant on the B. atrox venom. The thrombolytic activity was inhibited (above 20%) only when induced by L. muta venom. The thrombolysis induced by the Bothrops sp. venoms was potentiated by the two extracts evaluated. Conclusions Both extracts presented pharmacological activity modulating the activity of toxins.

Multicomponent reactions are extremely relevant in green chemistry. They offer better conditions than traditional synthesis and are, therefore, used for many organic modifications. Recently, the synthesis of polyhydroquinolines has received much attention for its high pharmacological potential. In the present study, a polyhydroquinoline derivative was synthesized without the use of catalysts or solvents. The results of nuclear magnetic resonance and infrared spectroscopy demonstrated that the molecule was successfully synthesized. The molecule presents significant results of antimicrobial activity for the bacteria tested in the serial dilution method. It also increased the clotting time by 25.66 seconds for the highest dose and 12.66 seconds for the other doses tested. Prior incubation with the dose of 125 mg reduced the thrombolytic activity to 73%. The 125, 100, and 50 mg doses previously incubated with Bothrops moojeni venom inhibited approximately 30% of the phospholipase activity. The molecule was also able to reduce the cytotoxicity induced by proteases significantly. In conclusion, the molecule presents several biological properties, which highlights its pharmaceutical potential.

The inflammatory process is a natural self-defense response of the organism to damage agents and its action mechanism involves a series of complex reactions. However, in some cases, this process can become chronic, causing much harm to the body. Therefore, over the years, many anti-inflammatory drugs have been developed aiming to decrease the concentrations of inflammatory mediators in the organism, which is a way of controlling these abnormal chain reactions. The main target of conventional anti-inflammatory drugs is the cyclooxygenase (COX) enzyme, but its use implies several side effects. Thus, based on these limitations, many studies have been performed, aiming to create new drugs, with new action mechanisms. In this sense, the phospholipase A2 (PLA2) enzymes stand out. Among all the existing isoforms, secretory PLA2 is the major target for inhibitor development, since many studies have proven that this enzyme participates in various inflammatory conditions, such as cancer, Alzheimer and arthritis. Finally, for the purpose of developing anti-inflammatory drugs that are sPLA2 inhibitors, many molecules have been designed. Accordingly, this work presents an overview of inflammatory processes and mediators, the current available anti-inflammatory drugs, and it briefly covers the PLA2 enzymes, as well as the diverse structural array of the newest sPLA2 inhibitors as a possible target for the production of new anti-inflammatory drugs.

Naja spp. venom is a natural source of active compounds with therapeutic application potential. Phospholipase A2 (PLA2) is abundant in the venom of Naja spp. and can perform neurotoxicity, cytotoxicity, cardiotoxicity, and hematological disorders. The PLA2s from Naja spp. venoms are Asp 49 isoenzymes with the exception of PLA2 Cys 49 from Naja sagittifera. When looking at the functional aspects, the neurotoxicity occurs by PLA2 called β-toxins that have affinity for phosphatidylcholine in nerve endings and synaptosomes membranes, and by α-toxins that block the nicotinic acetylcholine receptors in the neuromuscular junctions. In addition, these neurotoxins may inhibit K+ and Ca++ channels or even interfere with the Na+/K+/ATPase enzyme. The disturbance in the membrane fluidity also results in inhibition of the release of acetylcholine. The PLA2 can act as anticoagulants or procoagulant. The cytotoxicity exerted by PLA2s result from changes in the cardiomyocyte membranes, triggering cardiac failure and hemolysis. The antibacterial activity, however, is the result of alterations that decrease the stability of the lipid bilayer. Thus, the understanding of the structural and functional aspects of PLA2s can contribute to studies on the toxic and therapeutic mechanisms involved in the envenomation by Naja spp. and in the treatment of pathologies.

Natural enzyme inhibitors have been widely described in literature because of its pharmacological and cosmetic applications. Fungi found in caves represent a promising source of bioactive substances that are still little explored scientifically. Thus, the present work evaluated the presence of enzymatic modulators in a filtrate obtained from the cultivation of the cave fungus Lecanicillium aphanocladii (Family: Cordycipitaceae). Snake venoms from Bothrops alternatus and Bothrops atrox were used as an enzymatic source for the induction of the phospholipase, proteolytic, thrombolytic, cytotoxic and coagulant activities. Compounds present in the fungal filtrate inhibited 50, 23·8, 26·6, 50·9 and 52·5% of the proteolytic, phospholipase, haemolytic, thrombolytic and coagulant activities respectively. The filtrate was not cytotoxic on erythrocytes, but induced partial dissolution of thrombi. Fungal enzyme inhibitors that have low or no toxicity and can be obtained on a large scale and at low cost are relevant in the medical-scientific context. Therefore, the inhibition of phospholipases A2 and proteases observed in the present work highlights the potential of fungal metabolites for the development of drugs that can be used in the treatment of haemostasis and inflammation-related disorders. Significance and Impact of the Study In this study, secondary metabolites synthesized by Lecanicillium aphanocladii, a fungus isolated from caves, demonstrated modulating action on proteases and phospholipases A2 present in snake venoms of the Bothrops genus, widely used as tools for the study of pathophysiology processes related to haemostasis and inflammation. The results suggest the possibility of future applications for these metabolites in the development of pharmaceuticals of medical-scientific interest.

The venoms of wasps are a complex mixture of biologically active compounds, such as low molecular mass compounds, peptides, and proteins. The aim of the study was to evaluate the action of wasp ven...

This study aims to investigate the effect of different cooling rates on the semen cryopreservation of curimba (Prochilodus lineatus). Nineteen ejaculates were obtained from adults males and cryopreserved at 15°C/min (CR15), 30°C/min (CR30) (controlled temperature inside and outside straw, speed was stable during freezing) and direct freezing in liquid nitrogen vapour (~35.6°C/min) (CRNV). The straws were thawed and seminal parameters evaluated. DNA fragmentation through the comet assay was assessed. A fresh sperm sample was not frozen and used for analyses. Data were submitted to an analysis of variance (ANOVA), and means were compared by Scott-Knott test (p 0.05) using the R Software. Mean motility percentage was 100%, and motility duration was 39.5 ± 5.7 s for the fresh sperm (subjective analysis); 58.9 ± 8.0% and 24.5 ± 5.7 s for CR15; 64.8 ± 4.8% and 26.5 ± 7.1 s for CR30; and 50.1 ± 16% and 25.7 ± 4.7 s for CRNV, respectively. Motility percentages were higher and equal between CR15 and CR30 compared to CRNV (p 0.05). Some sperm motion kinetics, namely average path velocity (VAP) and straight line velocity (VAS), were higher for CR30 (p 0.05), while curvilinear velocity (VCL) and velocity progression (PRO) were lower for CRNV (p 0.05). Straightness (STR) and wobble (WOB) were the same among treatments (p 0.05). Sperm morphology results indicated higher means for total morphological sperm alterations in CRNV. All cooling rates caused sperm DNA fragmentation, although CR30 provided a less harmful effect. This is the first report for cryopreserved P. lineatus sperm preserved under different controlled cooling rates. The cooling rate of 30°C/min is indicated for the cryopreservation of this fish sperm as it led to the lowest detrimental spermatozoa effects.

A large number of natural compounds, such as phenolic compounds, have been scientifically evaluated in the search for enzyme inhibitors. The interactions between the phenolic compound p-coumaric acid and the enzymes present in snake venoms (used as research tools) were evaluated in vitro and in silico. The p-coumaric acid was able to inhibit 31% of the phospholipase activity induced by Bothrops alternatus venom, 27% of the hemolytic activity induced by B. moojeni, 62.5% of the thrombolytic activity induced by B. jararacussu, and approximately 27% of the activity thrombosis induced by Crotalus durissus terrificus. Previous incubation of p-coumaric acid with the venoms of B. atrox and B. jararacussu increased the coagulation time by 2.18 and 2.16-fold, respectively. The activity of serine proteases in B. atrox and B. jararacussu venoms was reduced by 60% and 66.34%, respectively. Computational chemistry analyses suggests the specific binding of p-coumaric acid to the active site of proteases through hydrogen and hydrophobic interactions. The phenolic compound evaluated in this work has great potential in therapeutic use to both prevent and treat hemostatic alterations, because the venom proteins inhibited by the p-coumaric acid have high homology with human proteins that have a fundamental role in several pathologies.

Made available in DSpace on 2022-04-28T19:41:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-08-31 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Snakebite envenoming is the cause of an ongoing health crisis in several regions of the world, particularly in tropical and neotropical countries. This scenario creates an urgent necessity for new practical solutions to address the limitations of current therapies. The current study investigated the isolation, phytochemical characterization, and myotoxicity inhibition mechanism of gallic acid (GA), a myotoxin inhibitor obtained from Anacardium humile. The identification and isolation of GA was achieved by employing analytical chromatographic separation, which exhibited a compound with retention time and nuclear magnetic resonance spectra compatible with GA's commercial standard and data from the literature. GA alone was able to inhibit the myotoxic activity induced by the crude venom of Bothrops jararacussu and its two main myotoxins, BthTX-I and BthTX-II. Circular dichroism (CD), fluorescence spectroscopy (FS), dynamic light scattering (DLS), and interaction studies by molecular docking suggested that GA forms a complex with BthTX-I and II. Surface plasmon resonance (SPR) kinetics assays showed that GA has a high affinity for BthTX-I with a KD of 9.146 × 10−7 M. Taken together, the two-state reaction mode of GA binding to BthTX-I, and CD, FS and DLS assays, suggest that GA is able to induce oligomerization and secondary structure changes for BthTX-I and -II. GA and other tannins have been shown to be effective inhibitors of snake venoms' toxic effects, and herein we demonstrated GA's ability to bind to and inhibit a snake venom PLA2, thus proposing a new mechanism of PLA2 inhibition, and presenting more evidence of GA's potential as an antivenom compound. Instituto de Genética e Bioquímica Universidade Federal de Uberlândia UFU Departamento de Biofísica e Farmacologia Instituto de Biociências Universidade Estadual Paulista UNESP Laboratório de Biotecnologia de Proteínas e Compostos Bioativos LABIOPROT Centro de Estudos de Biomoléculas Aplicadas à Saúde CEBio Laboratório de Imunologia Celular Aplicada à Saúde Fundação Oswaldo Cruz FIOCRUZ Unidade Rondônia Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renováveis IBAMA Departamento de Química Universidade Federal de Lavras UFLA Instituto Federal Goiano IF Goiano Faculty of Chemical Sciences University of Cuenca LAQV/Requimte Faculty of Sciences University of Porto Centro Universitário São Lucas UniSL Instituto Nacional de Ciência e Tecnologia em Epidemiologia da Amazônia Ocidental (INCT-EpiAmO) Departamento de Biofísica e Farmacologia Instituto de Biociências Universidade Estadual Paulista UNESP

Snakebite envenoming is the cause of an ongoing health crisis in several regions of the world, particularly in tropical and neotropical countries. This scenario creates an urgent necessity for new practical solutions to address the limitations of current therapies. The current study investigated the isolation, phytochemical characterization, and myotoxicity inhibition mechanism of gallic acid (GA), a myotoxin inhibitor obtained from Anacardium humile. The identification and isolation of GA was achieved by employing analytical chromatographic separation, which exhibited a compound with retention time and nuclear magnetic resonance spectra compatible with GA's commercial standard and data from the literature. GA alone was able to inhibit the myotoxic activity induced by the crude venom of Bothrops jararacussu and its two main myotoxins, BthTX-I and BthTX-II. Circular dichroism (CD), fluorescence spectroscopy (FS), dynamic light scattering (DLS), and interaction studies by molecular docking suggested that GA forms a complex with BthTX-I and II. Surface plasmon resonance (SPR) kinetics assays showed that GA has a high affinity for BthTX-I with a K

Fungi Induratia have been poorly evaluated for their non-volatile secondary metabolites. In the present work, we evaluated the effects of non-volatile secondary metabolites released into the culture medium by Induratia spp. upon toxic alterations induced by Bothrops spp. venoms. B. atrox venom phospholipase was inhibited by Induratia sp. and I. yucatanensis around 12 and 16%. The extracts of two strains inhibited 12 to 25% of the hemolysis induced by B.moojeni venom. Thrombolysis was inhibited by 30 to 60% by the compounds present in two extracts. The coagulation induced by B. moojeni venom was prolonged by 26 to 41 s by the action of the extracts of I. yucatanensis and I. coffeana. The fungal extracts did not exerted any cytotoxic effect, nor did they induce any alteration in the other evaluated substrates show the potential use of non-volatile metabolites produced by the fungi evaluated as enzyme modulators, especially for proteases with a fundamental role in human hemostasis.

Snake toxins, such as phospholipases A2 and proteases, are used as research tools to evaluate biological activities and to understand physiopathological processes of natural compounds better. In the present study, the phenolic compounds catechin and epicatechin were incubated with snake venoms to evaluate their inhibition against different substrates. Catechin and epicatechin exerted inhibitions between 20% and 95% on the activity of phospholipases A2 present in the venom of Bothrops alternatus. In the hemolytic activity, catechin exerted inhibitions between 20% and 25% in all proportions evaluated on the B. jararacussu venom, whereas epicatechin inhibited 20% of the venom activity. Coagulation induced by B. atrox and B. jararacussu venoms was significantly inhibited by catechin and epicatechin, where the time for coagulation was two to three times higher after previous incubation of the venoms with the compounds. The most significant inhibitions for the proteolytic activity on casein were 17% and 27%, respectively, by both compounds. Catechin inhibited serine protease activity induced by B. atrox venom by 64% and epicatechin by 65%. Regarding B. atrox-induced thrombolysis, catechin exerted 40% inhibition and epicatechin around 30%. The fibrinogen proteolysis was completely inhibited by catechin acting on the B. atrox venom in the proportion of 1:1 and by epicatechin on B. jararacussu venom. Catechin and epicatechin showed promising inhibitory action on proteases and phospholipases A2 . Therefore, these compounds can be explored as an adjuvant for serum therapy or pharmaceutical purposes, once they act on homologous enzymes that are present in humans.

In the present work, ethyl acetate extracts, consisting of non-volatile compounds, from the culture of endophytic fungi isolated from coffee plants, Induratia coffeana and Induratia yucatanensis, were prospected in enzyme modulation tests that act in human hemostasis. Dry extracts of the fungi were diluted in dimethyl sulfoxide p.a. 99.9% (DMSO), and then tested. Bothrops atrox venom was used as an enzyme source and tool to induce the activities. Prior to the evaluation of the activities, incubations of the extracts with the venom were performed in the proportions 1: 0.01, 1: 0.25, 1: 0.5, and 1: 1 (venom: extract; mass: mass). The extracts of all fungi promoted a significant increase in the clotting time induced by the venom, which was even longer when the extracts were previously incubated with the citrated plasma. The activity of phospholipases A2 did not significantly change when evaluated in the presence of fungal extracts. However, the evaluated extracts inhibited proteases by 73% and 30% in the thrombolytic and caseinolytic tests, respectively. In addition, the extracts did not induce cytotoxicity on human erythrocytes when evaluated in the absence of the venom. Thus, it is possible to suggest the presence of specific interactions between molecules present in extracts of Induratia spp. and venom proteases, highlighting non-volatile metabolites as promising sources of compounds of medical and scientific interest.

Background: Essential oils are complex mixtures of low molecular weight compounds extracted from plants. Their main constituents are terpenes and phenylpropanoids, which are responsible for their biological and pharmaceutical properties, such as insecticidal, parasiticidal, antimicrobial, antioxidant, anti-inflammatory, analgesic, antinociceptive, anticarcinogenic, and antitumor properties. Cancer is a complex genetic disease considered as a serious public health problem worldwide, accounting for more than 8 million deaths annually. Objective: The activities of prevention and treatment of different types of cancer and the medicinal potential of essential oils are addressed in this review. Conclusion: Several studies have demonstrated anti-carcinogenic and antitumor activity for many essential oils obtained from various plant species. They may be used as a substitution to or in addition to conventional anti-cancer therapy. Although many studies report possible mechanisms of action for essential oils compounds, more studies are necessary in order to apply them safely and appropriately in cancer therapy.

Agro-industrial wastes are promising sources of phytochemicals for the development of products to be used in health promotion and maintenance. In this study, extracts from acerola bagasse (AB) were characterized by HPLC, and evaluated according to its modulatory action on phospholipases A2 and proteases involved in processes such as inflammation and blood clotting. Snake venoms were used as biological tools once they have high functional and structural homology between their enzymes and human enzymes. Two types of extracts were prepared from AB: aqueous and methanolic. These extracts, evaluated at different proportions (venom:extract, w:w), significantly inhibited the phospholipase activity induced by the venoms of Bothrops moojeni, Bothrops atrox (11% to 31%), and Crotalus durissus terrificus (C. d. t.) (11% to 19%). The hemolytic activity induced by the venoms of B. moojeni and C. d. t. was better inhibited by the methanolic extract (inhibition between 23% and 48%). Thrombolysis induced by the venoms of B. moojeni and C. d. t. was inhibited by both extracts, with inhibition ranging from 13% to 63% for the aqueous extract, and from 12% to 92% for the methanolic one. Both extracts increased the time of coagulation induced by the venoms of B. moojeni and Lachesis muta muta in 26 and up to 68 s. These inhibitory actions were related to the following phenolic compounds present in the extract of AB: gallic acid, catechin, epigallocatechin gallate, epicatechin, syringic acid, p-coumaric acid, and quercetin. Additional studies are needed to confirm their potential use for nutraceutical purposes. PRACTICAL APPLICATION: Agro-industrial wastes are promising sources of phytochemicals for the development of products that can be used by pharmaceutical, cosmetics, and food industries. Studies report the use of the acerola bagasse extract in health improvement. However, its toxic-pharmacological characterization is still scarce. In this study, the extracts of acerola bagasse presented phenolic compounds that can modulate the activity of enzymes such as phospholipases A2 and proteases that act on the coagulant/anticoagulant and thrombotic/thrombolytic activities and the break of phospholipids, decreasing the inflammation and platelet aggregation. Although the in vivo effects of the extracts are not fully understood, this study shed light upon the possibilities of their usage.; © 2018 Institute of Food Technologists®.

Enzymatic inhibition by natural compounds may represent a valuable adjuvant in snakebite serum therapy. The objective in this work was to evaluate possible in vitro interactions between vanillic acid and enzymes from Bothrops spp. and Crotalus durissus terrificus venoms, and also suggest a theory as how they interact based on molecular docking. Vanillic acid inhibited the phospholipase activity induced by Bothrops alternatus (∼25% inhibition); the caseinolytic activity induced by Bothrops atrox (∼30%), Bothrops jararacussu (∼44%), and C. d. terrificus (∼33%); the fibrinogenolysis induced by B. jararacussu, B. atrox, and C. d. terrificus (100%); the serine protease activity induced by Bothrops moojeni (∼45%) and Bothrops jararaca (∼66%); the hemolytic activity induced by B. moojeni (∼26%); the thrombolysis activity induced by B. atrox (∼30%) and B. jararacussu (∼20%); and the thrombotic activity induced by C. d. terrificus (∼8%). The compound was also capable of delaying the coagulation time in citrated plasma by 60, 35, and 75 Sec, when incubated with B. moojeni, B. atrox, and B. jararaca, respectively. The results obtained expand the possibilities for future pharmaceutical use of vanillic acid, considering the high homology degree among human and snake venom phospholipases A

The protective action of caffeic (CA) and syringic (SA) acids on the genotoxicity exercised by snake venoms was investigated in this study. Molecular interactions between phenolic acids and the enzyme succinate dehydrogenase were also explored. In the electrophoresis assay, SA did not inhibit the genotoxicity induced by the venom. However, CA partially inhibited DNA degradation. In the comet assay, SA and CA exerted an inhibitory effect on the venom-induced fragmentation. Succinate dehydrogenase presented, in computational analyzes, favorable energies to the molecular bond to both the malonic acid and the phenolic compounds evaluated. In the enzymatic activity assays, SA inhibited succinate dehydrogenase and interfered in the interaction of malonic acid. Meanwhile, CA potentiated the inhibition exerted by the malonic acid. The results suggest transient interactions between toxins present in venoms and phenolic acids, mainly by hydrogen interactions, which corroborate with the data from previous works.

Snake venoms are widely used as laboratory tools for studies of physiological, pharmacological and toxicological mechanisms. Venoms used here are rich sources of several classes of proteases that act on factors of the coagulation cascade, fibrinogenolysis and fibrinolysis, altering the hemostatic processes, and phospholipases A2 which are involved mainly in inflammatory and clotting processes. Natural products such as essential oils are made up of active ingredients with wide application in the food, pharmaceutical and cosmetic industries. Thus, this study evaluates the essential oils from Mentha viridis and Mentha pulegium on coagulation, fibrinogenolysis and degradation of azocasein, induced by Bothrops sp and Lachesis muta muta venoms. These oils were achieved by hydrodistillation and presented, respectively, as the main constituents linalool (40.70 %), carvone (13.52 %) and α-terpinene (8.56 %); pulegone (50.01 %), menthol (31.90 %) and menthone (16.56 %). The essential oils were previously incubated with Bothrops alternatus venom, for two different times, then plasma was added and time was recorded. The M. viridis oil presented greater anticlotting potential. Meanwhile, the M. pulegium oil presented anticlotting or proclotting activity dependent on the dose tested. The incubation time also influenced the effect of the oils on the coagulation time. At azocaseinolytic assay, the oil from M. pulegium reduced the activity for all evaluated venoms. The highest inhibition was of 39.99 %; on activity induced by B. jararacussu, M. viridis reduced the activity in 57.72 %. On B. moojeni, the major inhibition observed was of 74.67 %. The fibrinogenolysis induced by B. moojeni venom was totally inhibited by both oils in the evaluated proportions. The results show the presence in oils of protease inhibitors, considering serine and metalloproteases (acting on clotting factors or with hemorrhagic activity), as well as phospholipase A2 (enzymes involved in inflammation and clotting processes) inhibitors of wide application in medical and biotechnology areas. RESUMEN Los venenos de serpientes son ampliamente utilizados como herramientas de laboratorio para estudios de mecanismos fisiológicos, farmacéuticos y toxicológicos. Los venenos son recursos ricos en diferentes clases de proteasas que actúan sobre los factores de la cascada de coagulación, fibrinogenólisis y fibrinólisis, alterando los procesos homeostáticos y las fosfolipasas A2, los cuales están involucrados en procesos inflamatorios y de coagulación. Los productos naturales como los aceites esenciales se componen de ingredientes activos de amplia aplicación en las industrias alimentaria, farmacéutica y cosmética. El presente estudio evalúa los aceites esenciales de Mentha viridis y Mentha pulegium sobre la coagulación, fibrinogenólisis y degradación de azocaseína, inducida por los venenos de Bothrops sp. y Lachesis muta muta. Los aceites esenciales fueron obtenidos por hidrodestilación y sus componentes principales fueron identificados respectivamente como el linalool (40.70 %), carvona (13.52 %) y α-terpineno (8.56 %); pulegone (50.01 %), mentol (31.9 %) y mentona (15.56 %). Los aceites esenciales fueron previamente incubados con veneno de Bothrops alternatus, durante dos tiempos diferentes, luego se agregó el plasma y fue registrado el tiempo. El aceite de M. viridis presentó el más grande potencial anticoagulante. Mientras tanto, el aceite de M. pulegium presentó actividad anticoagulante o procoagulante dependiendo de la dosis evaluada. El tiempo de incubación también influyó en el efecto de los aceites sobre el tiempo de coagulación. En el ensayo azocaseínolitico, el aceite de M. pulegium redujo la actividad para todos los venenos evaluados. La inhibición más alta inducida para el veneno de B. jararacussu fue de 39.99 %, para M. viridis la actividad fue reducida en 57.72 %, mientras que para B. moojeni, la mayor inhibición observada fue de 74.67 %. La fibrinogenólisis inducida por el veneno de B. moojeni fue totalmente inhibida por ambos aceites en las proporciones evaluadas. Los resultados muestran la presencia de inhibidores de proteasas en los aceites, como las serinas y metaloproteasas (actuando sobre los factores de coagulación o sobre la actividad hemorrágica), como también fosfolipasas A2 (enzimas involucradas en los procesos de inflamación y coagulación), los cuales son inhibidores de amplia aplicación en áreas médicas y biotecnológicas.

The phenolic extracts of jabuticaba skin flour (JSF) were characterized by HPLC, and evaluated for their modulating action upon phospholipases A2 and proteases of snake venom, aiming at their possible use in the treatment of the various diseases associated with the action of venom toxins. Two types of extracts were prepared from JSF: aqueous and methanolic. These extracts, evaluated at different ratios, (venom: extract, m/m), significantly inhibited the phospholipase activity induced by the venom of Bothrops moojeni and Crotalus durissus terrificus, except for Bothrops atrox venom. The greatest hemolysis inhibitory action was observed for the methanolic extract, when incubated with venoms of B. moojeni and C. durissus terrificus, with inhibitions between 21 and 100%. Thrombolysis induced by venoms of B. moojeni and C. durissus terrificus was inhibited by both extracts, ranging from 32 to 83% and 51 to 83% for the aqueous and methanolic extracts, respectively. Both extracts extended coagulation time, induced by the venoms of B. moojeni and Lachesis muta muta. Inhibitory actions are related to phenolic compounds, such as gallic, syringic and p-coumaric acids, besides catechin, epigallocatechin gallate, epicatechin; resveratrol and quercetin, present in the extracts of jabuticaba skin flour, confirming their potential for nutraceutical use.

Naja spp. venom is a natural source of active compounds with therapeutic application potential. Phospholipase A

The essential oils from Mentha piperita, Cymbopogon citratus, Rosmarinus officinalis, Peumus boldus and Foeniculum vulgare were extracted by hydrodistillation and characterized and quantified by GC-MS and GC-DIC. The oils induced hemolysis with all the doses evaluated (0.6 to 1.8 μL), and the diameters of the halos varied between 9 and 15 mm. Pre-incubation of P. boldus oil with Bothrops jararacussu venom resulted in potentiation of venom-induced hemolysis (30%) (proteases and phospholipases A2). The essential oil from M. piperita (0.6 μL) inhibited venom-induced hemolysis by 45%, whereas 0.6 μL of R. officinalis oil increased the hemolysis by 20%. For the essential oil from F. vulgare, 100% inhibition of activity (0.6 and 1.2 μL) was observed. The application of C. citratus oil induced hemolysis with all the volumes evaluated. Phospholipase activity induced by the venom was only inhibited (10%) with the 0.6 μL volume of R. officinalis oil. The oils from M. piperita and F. vulgare (1.8 μL) and C. citratus oil (0.6 μL) potentiated the phospholipase activity. The results highlight the need for a broad characterization and regulation of the use of natural products, because they can have therapeutic or toxic actions.

The essential oils from Mentha viridis (L). L. and Mentha pulegium L. were studied to assess their inhibitory potential on phospholipase from snake venoms and to determine their cytogenotoxic action on human cells. These essential oils were able to inhibit the breakdown of phospholipids induced by venoms of snakes of the Bothrops genus. Both oils presented hemolytic activity, although the Mentha viridis (L). L. oil induced hemolysis only at the highest concentrations (14.6 and 29 μL&#183mL-1). The essential oil from M. viridis induced 3.9; 8.6 and 16.2 times greater damage to human leukocyte DNA than that observed with the positive control (100 μg&#183μL-1 doxorubicin) at concentrations of 0.25; 0.5 and 1.0 μL&#183mL-1, respectively. A similar effect was observed for the oil from M. pulegium (2.1, 2.5 and 15.8 times greater damage). The results extend the characterization of these essential oils and demonstrate their potential use in industries.

Disintegrins are non-enzymatic proteins that interfere on cell–cell interactions and signal transduction, contributing to the toxicity of snake venoms and play an essential role in envenomations. Most of their pharmacological and toxic effects are the result of the interaction of these molecules with cell surface ligands, which has been widely described and studied. These proteins may act on platelets, leading to hemorrhage, and may also induce apoptosis and cytotoxicity, which highlights a high pharmacological potential for the development of thrombolytic and antitumor agents. Additionally, these molecules interfere with the functions of integrins by altering various cellular processes such as migration, adhesion and proliferation. This review gathers information on functional characteristics of disintegrins isolated from snake venoms, emphasizing a comprehensive view of the possibility of direct use of these molecules in the development of new drugs, or even indirectly as structural models.

The objective of this study was to evaluate the genotoxic and mutagenic effects of the toxins present in Lachesis muta muta's venom on human peripheral blood leukocytes and the protective potential of ascorbic acid on DNA fragmentation. The venom of L. muta muta was incubated in different concentrations (1, 2.5, 5, 7.5, 10, 15, 20, 30, 40, 50, 60, and 120 µg/mL) with human blood to evaluate DNA fragmentation using the comet, agarose gel electrophoresis, and micronucleus assays. In these concentrations evaluated, the venom of L. muta muta induced genotoxicity (comet assay and agarose gel electrophoresis) and mutagenicity (micronucleus test), but they were not cytotoxic, as they did not change the rate of cell proliferation after cytokinesis blockade with cytochalasin B. The ascorbic acid significantly inhibited the genotoxicity induced by L. muta muta venom in the proportions evaluated (1:0.1 and 1:0.5, venom/ascorbic acid - w/w). Thus, future studies are needed to elucidate the protective mechanisms of ascorbic acid on the genotoxic effects induced by toxins present in snake venoms.

Metalloproteases play a fundamental role in snake venom envenomation inducing hemorrhagic, fibrigen(ogen)olytic and myotoxic effects in their victims. Several snake venoms, such as those from the Bothrops genus, present important local effects which are not efficiently neutralized by conventional serum therapy. Consequently, these accidents may result in permanent sequelae and disability, creating economic and social problems, especially in developing countries, leading the attention of the World Health Organization that considered ophidic envenomations a neglected tropical disease. Aiming to produce an efficient inhibitor against bothropic venoms, we synthesized different molecules classified as quinolinones – a group of low-toxic chemical compounds widely used as antibacterial and antimycobacterial drugs – and tested their inhibitory properties against hemorrhage caused by bothropic venoms. The results from this initial screening indicated the molecule 2-hydroxymethyl-6-methoxy-1,4-dihydro-4-quinolinone (Q8) was the most effective antihemorrhagic compound among all of the assayed synthetic quinolinones. Other in vitro and in vivo experiments showed this novel compound was able to inhibit significantly the hemorrhagic and/or proteolytic activities of bothropic crude venoms and isolated snake venom metalloproteases (SVMPs) even at lower concentrations. Docking and molecular dynamic simulations were also performed to get insights into the structural basis of Q8 inhibitory mechanism against proteolytic and hemorrhagic SVMPs. These structural studies demonstrated that Q8 may form a stable complex with SVMPs, impairing the access of substrates to the active sites of these toxins. Therefore, both experimental and structural data indicate that Q8 compound is an interesting candidate for antiophidic therapy, particularly for the treatment of the hemorrhagic and necrotic effects induced by bothropic venoms.

The aim of this study was to evaluate the therapeutic and toxicologic effects of the administration of the powered vegetable extract and aqueous extract of Tournefortia paniculata leaves on Wistar rats, subjected to a hypercaloric diet for 42 days. The rats were divided into five groups and were given the following treatments by gavage: T0 (control) - 1.0 mL water day-1; T1 - aqueous extract containing 14 mg phenolic compounds kg-1 rat day-1; T2 - 14 mg quercetin kg-1 rat day-1; T3 - 50 mg powered vegetable extract from T. paniculata leaves (PVE) kg-1 rat day-1 and T4 - 100 mg PVE kg-1 rat day-1. The treatments did not significantly alter the weight, but were effective in reducing liver fat, glucose and serum triglycerides. The treatment T1 reduced food consumption and lipid peroxidation. None of the treatments showed genotoxic potential. Results showed that T. paniculata leaves possessed an anti-obesity potential. However, a more detailed study of the medicinal potential and characterization of phytochemicals in this plant would be still necessary for a better understanding of its mechanisms of action, enabling future applications in the treatment of this pathology or for various therapeutic purposes.

The objective of this study was to determine cytotoxic activity, hemolytic activity, and to evaluate the ability of the essential oil from Cinnamodendron dinisii to induce DNA fragmentation of human lymphocytes. The essential oil was obtained by hydrodistillation. Cytotoxic activity was determined by the MTT method. Hemolytic activity was evaluated by spectrophotometric quantification of hemoglobin released by erythrocytes. Damage to lymphocyte DNA molecules was assessed by the Comet assay. The essential oil under study showed high cytotoxic activity on Vero cells (CC50 = 35.72 μg/mL) and induced hemolysis in both hematocrits, besides leading to the oxidation of hemoglobin released. The genotoxic activity of C. dinisii essential oil was also observed, which induced concentration-dependent DNA fragmentation of human lymphocytes and, at 50 μL/mL, it was more active than the positive control. The essential oil from C. dinisii has a toxic action, suggesting a special attention in the application of this oil to health-promoting activities; however, among its components, there are molecules with potential for future application in anticancer therapies.

The effects of different concentrations of commercial product based on tebuconazole, on adults of Danio rerio, were evaluated through novel tank diving test and micronucleus and comet assay tests. A total of 320 adult D. rerio were divided into eight tanks and exposed to concentrations of 0; 100; 200 and 300 μg/L the commercial product based on tebuconazole, with their respective replicates at 24, 72 and 96 h. The results showed a behavioral deviation of zebrafish and a significant (p < 0.05) increase in DNA damage as a function of exposed time and different concentrations of the commercial product in relation to the negative control. The results obtained in this study allow to conclude that tebuconazole has effects on adults of Danio rerio, inducing genotoxicity and mutagenicity, as well as altering neurological functions related to the change in the behavior of adults.

Made available in DSpace on 2018-12-11T17:38:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-08-28. Added 1 bitstream(s) on 2019-10-09T18:33:19Z : No. of bitstreams: 1 S1678-91992018000100313.pdf: 5810239 bytes, checksum: 1f7caf8f8612205ab464347b78c03c91 (MD5) Background: Cnidarians produce toxins, which are composed of different polypeptides that induce pharmacological effects of biotechnological interest, such as antitumor, antiophidic and anti-clotting activities. This study aimed to evaluate toxicological activities and potential as antitumor and antiophidic agents contained in total extracts from five cnidarians: Millepora alcicornis, Stichodactyla helianthus, Plexaura homomalla, Bartholomea annulata and Condylactis gigantea (total and body wall). Methods: The cnidarian extracts were evaluated by electrophoresis and for their phospholipase, proteolytic, hemorrhagic, coagulant, fibrinogenolytic, neuromuscular blocking, muscle-damaging, edema-inducing and cytotoxic activities. Results: All cnidarian extracts showed indirect hemolytic activity, but only S. helianthus induced direct hemolysis and neurotoxic effect. However, the hydrolysis of NBD-PC, a PLA2 substrate, was presented only by the C. gigantea (body wall) and S. helianthus. The extracts from P. homomalla and S. helianthus induced edema, while only C. gigantea and S. helianthus showed intensified myotoxic activity. The proteolytic activity upon casein and fibrinogen was presented mainly by B. annulata extract and all were unable to induce hemorrhage or fibrinogen coagulation. Cnidarian extracts were able to neutralize clotting induced by Bothrops jararacussu snake venom, except M. alcicornis. All cnidarian extracts were able to inhibit hemorrhagic activity induced by Bothrops moojeni venom. Only the C. gigantea (body wall) inhibited thrombin-induced coagulation. All cnidarian extracts showed antitumor effect against Jurkat cells, of which C. gigantea (body wall) and S. helianthus were the most active; however, only C. gigantea (body wall) and M. alcicornis were active against B16F10 cells. Conclusion: The cnidarian extracts analyzed showed relevant in vitro inhibitory potential over the activities induced by Bothrops venoms; these results may contribute to elucidate the possible mechanisms of interaction between cnidarian extracts and snake venoms. Centro de Estudos de Biomoléculas Aplicadas a Saúde (CEBio) Fundação Oswaldo Cruz de Rondônia (Fiocruz Rondônia) Brazilian Marine Biotechnology Network (BioTecMar Network) Universidade Federal de Rondônia (UNIR) Departamento de Medicina Universidad de La Habana Centro de Estudios de Proteínas Facultad de Biología Universidade Federal de Lavras (UFLA) Departamento de Química Universidade Federal Fluminense (UFF) Departamento de Biologia Celular e Molecular (GCM) Instituto de Biologia Universidade Estadual Paulista (UNESP) Departamento de Farmacologia Instituto de Biociências Universidade Federal de Minas Gerais (UFMG) Instituto de Ciências Biológicas Departamento de Farmacologia Universidade Estadual Paulista (UNESP) Departamento de Morfologia Instituto de Biociências Centro Universitário São Lucas (UniSL) Universidade Estadual Paulista (UNESP) Departamento de Farmacologia Instituto de Biociências Universidade Estadual Paulista (UNESP) Departamento de Morfologia Instituto de Biociências