Evaluation of Rhamnetin as an Inhibitor of the Pharmacological Effect of Secretory Phospholipase A2.

Rhamnetin (Rhm), 3--methylquercetin (3MQ), and Rhamnazin (Rhz) are methylated derivatives of quercetin commonly found in fruits and vegetables that possess antioxidant and anti-inflammatory properties. Phospholipase A2 (PLA2) displays several important roles during acute inflammation; therefore, this study aimed at investigating new compounds able to inhibit this enzyme, besides evaluating creatine kinase (CK) levels and citotoxicity. Methylated quercetins were compared with quercetin (Q) and were incubated with secretory PLA2 (sPLA2) from to determine their inhibitory activity.

Evaluation of macroalgae sulfated polysaccharides on the Leishmania (L.) amazonensis promastigote.

The sulfated polysaccharides from Solieria filiformis (Sf), Botryocladia occidentalis (Bo), Caulerpa racemosa (Cr) and Gracilaria caudata (Gc) were extracted and extensively purified. These compounds were then subjected to in vitro assays to evaluate the inhibition of these polysaccharides on the growth of Leishmania (L.) amazonensis promastigotes.

The extract of the jellyfish Phyllorhiza punctata promotes neurotoxic effects.

Phyllorhiza punctata (P. punctata) is a jellyfish native to the southwestern Pacific. Herewith we present the biochemical and pharmacological characterization of an extract of the tentacles of P.

Quercetin as an inhibitor of snake venom secretory phospholipase A2.

As polyphenolic compounds isolated from plants extracts, flavonoids have been applied to various pharmaceutical uses in recent decades due to their anti-inflammatory, cancer preventive, and cardiovascular protective activities. In this study, we evaluated the effects of the flavonoid quercetin on Crotalus durissus terrificus secretory phospholipase A2 (sPLA2), an important protein involved in the release of arachidonic acid from phospholipid membranes. The protein was chemically modified by treatment with quercetin, which resulted in modifications in the secondary structure as evidenced through circular dichroism.

Antibacterial and antiparasitic effects of Bothrops marajoensis venom and its fractions: Phospholipase A2 and L-amino acid oxidase.

Some proteins present in snake venom possess enzymatic activities, such as phospholipase A(2) and l-amino acid oxidase. In this study, we verify the action of the Bothrops marajoensis venom (BmarTV), PLA(2) (BmarPLA(2)) and LAAO (BmarLAAO) on strains of bacteria, yeast, and Leishmania sp. The BmarTV was isolated by Protein Pack 5PW, and several fractions were obtained.

Purification and biological effects of L-amino acid oxidase isolated from Bothrops insularis venom.

Bothrops insularis is a snake from Ilha da Queimada Grande, an island located about 20 miles away from the Southeastern coast of Brazil. Compared with other Brazilian species of Bothrops, the toxinology of B. insularis is still poorly understood, and so far, no fraction from this venom with amino acid oxidase activity had been isolated or its biological activity tested.

Purification and renal effects of phospholipase A(2) isolated from Bothrops insularis venom.

Bothrops insularis venom contains a variety of substances presumably responsible for several pharmacological effects. We investigated the biochemical and biological effects of phospholipase A(2) protein isolated from B. insularis venom and the chromatographic profile showed 7 main fractions and the main phospholipase A(2) (PLA(2)) enzymatic activity was detected in fractions IV and V.

Purification and biological activity of the thrombin-like substance isolated from Bothrops insularis venom.

The venom of Bothrops insularis snake, known in Brazil as jararaca ilhoa, contains a variety of proteolytic enzymes such as a thrombin-like substance that is responsible for various pharmacological effects. B. insularis venom chromatography profile showed an elution of seven main fractions.

Purification and biological effects of Araucaria angustifolia (Araucariaceae) seed lectin.

This paper describes the purification and characterization of a new N-acetyl-d-glucosamine-specific lectin from Araucaria angustifolia (AaL) seeds (Araucariaceae) and its anti-inflammatory and antibacterial activities. AaL was purified using a combination of affinity chromatography on a chitin column and ion exchange chromatography on Sephacel-DEAE. The pure protein has 8.

Purification and biological effects of C-type lectin isolated from Bothrops insularis venom.

Bothrops insularis is a snake from Queimada Grande Island, which is an island located about 20 miles away from the southeastern coast of Brazil. Compared to other Brazilian species of Bothrops, the toxinology of B. insularis is still poorly understood.

Crotacetin, a novel snake venom C-type lectin homolog of convulxin, exhibits an unpredictable antimicrobial activity.

Snake venom (sv) C-type lectins encompass a group of hemorrhagic toxins that are capable of interfering with blood stasis. A very well-studied svC-type lectin is the heterodimeric toxin, convulxin (CVX), from the venom of South American rattlesnake Crotalus durissus terrificus. CVX is able to activate platelets and induce their aggregation by acting via p62/GPVI collagen receptor.

Biochemical, pharmacological and structural characterization of a new PLA2 from Crotalus durissus terrificus (South American rattlesnake) venom.

A new PLA2 (F16) was purified from Crotalus durissus terrificus venom by molecular exclusion chromatography followed by analytical reverse phase HPLC. The PLA2 (14.86 kDa by MALDI-TOF mass spectrometry) had an amino acid sequence of SLLQFNKMIKFETRKNAVPFYAFYGCYCGWGGRRRPKDATDRCCFVHDCCYEKVTKCNTKWDIYRYSLKSGYITCGKGTWCKEQICECDRVAAECLRRSLSTYKNGYMFYPDSRCRGPSETC, and showed highly conserved Ca2+-binding and catalytic sites.

Effects of morin on snake venom phospholipase A2 (PLA2).

Flavonoids are potent anti-inflammatory compounds isolated from several plant extracts, and have been used experimentally against inflammatory processes. In this work, a PLA2 isolated from the Crotalus durissus cascavella venom and rat paw oedema were used as a model to study the effect of flavonoids on PLA2. We observed that a treatment of PLA2 with morin induces several modifications in the aromatic amino acids, with accompanying changes in its amino acid composition.

A new C-type animal lectin isolated from Bothrops pirajai is responsible for the snake venom major effects in the isolated kidney.

We investigated the biochemical and biological effects of a new C-type galactoside specific lectin termed BPL that was isolated from the snake venom of Bothrops pirajai. This lectin was purified using size exclusion HPLC followed by an immobilized lactose affinity column. The purified BPL was homogeneous by reverse phase HPLC and SDS-PAGE.