The First Anti-Snakebite and Hepatoprotective Characterization of a Trypsin Kunitz-like Inhibitor (EcTI) from the Plant A Case of Two Soul Mates Meeting.

Snake venom serine protease (SVSP) interferes with the regulation and control of important biological reactions in homeostasis and can be classified as an activator of the fibrinolytic system and platelet aggregation. Our group has recently isolated a new serine protease from total venom (Cdtsp-2). This protein exhibits edematogenic capacity and myotoxic activity.

In Silico Evaluation of Quercetin Methylated Derivatives on the Interaction with Secretory Phospholipases A2 from and .

Quercetin derivatives have already shown their anti-inflammatory potential, inhibiting essential enzymes involved in this process. Among diverse pro-inflammatory toxins from snake venoms, phospholipase A2 is one of the most abundant in some species, such as and from the Viperidae family. These enzymes can induce the inflammatory process through hydrolysis at the sn-2 position of glycerophospholipids.

Adenanthin Is an Efficient Inhibitor of Peroxiredoxins from Pathogens, Inhibits Bacterial Growth, and Potentiates Antibiotic Activities.

The emergence and re-emergence of bacterial strains resistant to multiple drugs represent a global health threat, and the search for novel biological targets is a worldwide concern. AhpC are enzymes involved in bacterial redox homeostasis by metabolizing diverse kinds of hydroperoxides. In pathogenic bacteria, AhpC are related to several functions, as some isoforms are characterized as virulence factors.

Gallic Acid as a Non-Selective Inhibitor of α/β-Hydrolase Fold Enzymes Involved in the Inflammatory Process: The Two Sides of the Same Coin.

(1) Background: Gallic acid (GA) has been characterized as an effective anti-inflammatory, antivenom, and promising drug for therapeutic use. (2/3) Methods and Results: GA was identified from ethanolic extract of fresh pitanga () leaves, which was identified using commercial GA. Commercial GA neutralized the enzymatic activity of secretory PLA2 (sPLA2) by inhibiting the active site and inducing changes in the secondary structure of the enzyme.

Effects of Serine or Threonine in the Active Site of Typical 2-Cys Prx on Hyperoxidation Susceptibility and on Chaperone Activity.

Typical 2-Cys peroxiredoxins (2-Cys Prx) are ubiquitous Cys-based peroxidases, which are stable as decamers in the reduced state, and may dissociate into dimers upon disulfide bond formation. A peroxidatic Cys (C) takes part of a catalytic triad, together with a Thr/Ser and an Arg. Previously, we described that the presence of Ser (instead of Thr) in the active site stabilizes yeast 2-Cys Prx as decamers.

Bothrops pauloensis snake venom-derived Asp-49 and Lys-49 phospholipases A2 mediates acute kidney injury by oxidative stress and release of inflammatory cytokines.

The envenomation caused by the Bothrops pauloensis snake leads to severe local and systemic effects including acute kidney injury. In this study, we investigated the renal effects by phospholipases A2 (PLA2s), divided into two main subgroups, Asp-49 and Lys-49, isolated from the Bothrops pauloensis snake venom (BpV) in isolated rat kidney system. Both PLA2s (3 μg/mL), added alone to the perfusion system and analyzed for 120 min, had significant effects on isolated rat kidney.

Influence of lysosomal protease sensitivity in the immunogenicity of the antitumor biopharmaceutical asparaginase.

L-asparaginase (ASNase) from Escherichia coli (EcAII) is used in the treatment of acute lymphoblastic leukaemia (ALL). EcAII activity in vivo has been described to be influenced by the human lysosomal proteases asparaginyl endopeptidase (AEP) and cathepsin B (CTSB); these hydrolases cleave and could expose epitopes associated with the immune response against EcAII. In this work, we show that ASNase resistance to CTSB and/or AEP influences the formation of anti-ASNase antibodies, one of the main causes of hypersensitivity reactions in patients.

The Human Pathogen Has a Unique 1-Cys Peroxiredoxin That Localizes Both Intracellularly and at the Cell Surface.

is a temperature-dependent dimorphic fungus that causes systemic paracoccidioidomycosis, a granulomatous disease. The massive production of reactive oxygen species (ROS) by the host's cellular immune response is an essential strategy to restrain the fungal growth. Among the ROS, the hydroperoxides are very toxic antimicrobial compounds and fungal peroxidases are part of the pathogen neutralizing antioxidant arsenal against the host's defense.

Functional and structural evaluation of the antileukaemic enzyme L-asparaginase II expressed at low temperature by different Escherichia coli strains.

Acute lymphoblastic leukaemia (ALL) affects lymphoblastic cells and is the most common neoplasm during childhood. Among the pharmaceuticals used in the treatment protocols for ALL, Asparaginase (ASNase) from Escherichia coli (EcAII) is an essential biodrug. Meanwhile, the use of EcAII in neoplastic treatments causes several side effects, such as immunological reactions, hepatotoxicity, neurotoxicity, depression, and coagulation abnormalities.

Glutaredoxin-like protein (GLP)-a novel bacteria sulfurtransferase that protects cells against cyanide and oxidative stresses.

The pathogen Xylella fastidiosa belongs to the Xanthomonadaceae family, a large group of Gram-negative bacteria that cause diseases in many economically important crops. A predicted gene, annotated as glutaredoxin-like protein (glp), was found to be highly conserved among the genomes of different genera within this family and highly expressed in X. fastidiosa.

BoaγPLI: Structural and functional characterization of the gamma phospholipase A2 plasma inhibitor from the non-venomous Brazilian snake Boa constrictor.

Plasma in several organisms has components that promote resistance to envenomation by inhibiting specific proteins from snake venoms, such as phospholipases A2 (PLA2s). The major hypothesis for inhibitor's presence would be the protection against self-envenomation in venomous snakes, but the occurrence of inhibitors in non-venomous snakes and other animals has opened new perspectives for this molecule. Thus, this study showed for the first time the structural and functional characterization of the PLA2 inhibitor from the Boa constrictor serum (BoaγPLI), a non-venomous snake that dwells extensively the Brazilian territory.

Bioaffinity Fishing Procedure Using Secretory Phospholipase A2 for Screening for Bioactive Components: Modulation of Pharmacological Effect Induced by sPLA2 from by Hispidulin from .

Bioaffinity capturing of molecules allows the discovery of bioactive compounds and decreases the need for various stages in the natural compound isolation process. Despite the high selectivity of this technique, the screening and identification methodology depends on the presence of a protein to capture potential ligands. However, some proteins, such as snake secretory phospholipase A2 (sPLA2), have never been investigated using this approach.

Evaluation of the Inhibitory Potential of Casuarictin, an Ellagitannin Isolated from White Mangrove () Leaves, on Snake Venom Secretory Phospholipase A2.

Ellagitannins constitute the largest group of hydrolyzable tannins of plants, and, from this group, casuarictin (Casu) was identified in some plant species. However, to our knowledge, no investigation of secretory phospholipase A2 (sPLA2) inhibition by Casu has been performed yet. Casuarictin was isolated by chromatography n-butanol (n-BuOH) partition of leaves.

LC-ESI-IT-MS/MS and MALDI-TOF Approach: Identification of Natural Polymers from Rhizophora mangle Barks and Determination of Their Analgesic and Anti-inflammatory Properties.

We recognize the chemical composition of the acetonic extract of Rhizophora mangle barks (AERM) using mass spectrometry analysis [liquid chromatography (LC)-ESI-IT-MS/MS and matrix-assisted laser desorption/ionization-time of flight-MS (MALDI-TOF)]. Analgesic activity was evaluated by formalin and tail-flick experimental assays. Anti-inflammatory activity was performed by paw edema test induced by carrageenan and 48/80 compounds.

Effect of phospholipase A inhibitors during infection caused by .

Background: Lipid metabolites play an important role in parasite differentiation and virulence. Studies have revealed that sp. uses prostaglandins to evade innate barriers, thus enabling the parasites to survive inside immune cells.

Edema Induced by a Venom Serine Protease (Cdtsp 2) Involves the PAR Pathway and PKC and PLC Activation.

Snake venom serine proteases (SVSPs) represent an essential group of enzymatic toxins involved in several pathophysiological effects on blood homeostasis. Some findings suggest the involvement of this class of enzymatic toxins in inflammation. In this paper, we purified and isolated a new gyroxin isoform from the (Cdt) venom, designated as Cdtsp 2, which showed significant proinflammatory effects in a murine model.

Evaluation of KIM-1 as an early biomarker of snakebite-induced AKI in mice.

Acute kidney injury (AKI) is one of the most important complications of bothropic poisoning and its early identification remains challenging. The nephrotoxicity of Bothrops insularis venom (BinsV) was previously described by our research group. In this study, we continued to evaluate the effect of BinsV on kidney function in mice and LLC-MK2 proximal tubule cells, evaluating KIM-1 protein as an early AKI biomarker.

Non-Clinical Studies for Evaluation of 8-C-Rhamnosyl Apigenin Purified from Peperomia obtusifolia against Acute Edema.

Compound 8--rhamnosyl apigenin (8CR) induced a moderate reduction in the enzymatic activity of secretory phospholipase A2 (sPLA2) from and cytosolic phospholipase A2 (cPLA2), but the compound also significantly inhibited the enzymatic activity of the enzyme cyclooxygenase. In vitro assays showed that the compound induced a slight change in the secondary structure of sPLA2 from snake venom. In vivo assays were divided into two steps.

Renal effects of Bunodosoma caissarum crude extract: Prostaglandin and endothelin involvement.

Sea anemones contain a variety of interesting biologically active compounds, including some potent toxins. PLA from Bunodosoma caissarum, a sea anemone endemic in the Brazilian southern coast, has shown renal alterations on isolated kidney. The aim of this study was to evaluate the renal and vascular effects of B.

Catalytic Thr or Ser Residue Modulates Structural Switches in 2-Cys Peroxiredoxin by Distinct Mechanisms.

Typical 2-Cys Peroxiredoxins (2-Cys Prxs) reduce hydroperoxides with extraordinary rates due to an active site composed of a catalytic triad, containing a peroxidatic cysteine (CP), an Arg, and a Thr (or Ser). 2-Cys Prx are involved in processes such as cancer; neurodegeneration and host-pathogen interactions. During catalysis, 2-Cys Prxs switch between decamers and dimers.

Involvement of Nitric Oxide on Bothropoides insularis Venom Biological Effects on Murine Macrophages In Vitro.

Viperidae venom has several local and systemic effects, such as pain, edema, inflammation, kidney failure and coagulopathy. Additionally, bothropic venom and its isolated components directly interfere on cellular metabolism, causing alterations such as cell death and proliferation. Inflammatory cells are particularly involved in pathological envenomation mechanisms due to their capacity of releasing many mediators, such as nitric oxide (NO).

Bothropoides pauloensis venom effects on isolated perfused kidney and cultured renal tubular epithelial cells.

Snake envenomation (Bothrops genus) is common in tropical countries and acute kidney injury is one of the complications observed in Bothrops snakebite with relevant morbidity and mortality. Here, we showed that Bothropoides pauloensis venom (BpV) decreased cell viability (IC50 of 7.5 μg/mL).

l-amino acid oxidase from Bothrops marajoensis causes nephrotoxicity in isolated perfused kidney and cytotoxicity in MDCK renal cells.

Renal alterations caused by Bothrops venom and its compounds are studied to understand these effects and provide the best treatment. Previously, we studied the renal effect of the whole venom of Bothrops marajoensis and its phospholipase A2 (PLA2), but these effects could not to be attributed to PLA2. To continue the study, we report in this short communication the effects of l-amino acid oxidase from B.

Evaluation of Potential Thrombin Inhibitors from the White Mangrove (Laguncularia racemosa (L.) C.F. Gaertn.).

The aim of this work was to verify the effects of methanol (MeOH) and hydroalcoholic (HA) extracts and their respective partition phases obtained from white mangrove (Laguncularia racemosa (L.) C.F.

L-Aminoacid Oxidase from Bothrops leucurus Venom Induces Nephrotoxicity via Apoptosis and Necrosis.

Acute renal failure is a common complication caused by Bothrops viper envenomation. In this study, the nefrotoxicity of a main component of B. leucurus venom called L-aminoacid oxidase (LAAO-Bl) was evaluated by using tubular epithelial cell lines MDCK and HK-2 and perfused kidney from rats.