The recombinant plant Bauhinia bauhinioides elastase inhibitor reduces rat thrombus without alterations in hemostatic parameters.

The anti-inflammatory effects of the plant protease inhibitor BbCI (Bauhinia bauhinioides cruzipain inhibitor), which blocks elastase, cathepsin G, and L, and proteinase 3 has been demonstrated. Here, we investigated the recombinant rBbCI-His (containing a histidine tail) in an experimental venous thrombosis model of vena cava (VC) ligature in rats, comparing to heparin. We evaluate the effects of the inhibitors (native or recombinant) or heparin on the activated partial thromboplastin time (aPTT) and prothrombin time (PT) in human and rat plasmas.

Biotechnological Potential of Pine Nuts Extract and the Cysteine Protease Inhibitor AaCI-2S.

Protease inhibitors are involved in the regulation of endogenous cysteine proteases during seed development and play a defensive role because of their ability to inhibit exogenous proteases such as those present in the digestive tracts of insects. seeds, which can be used in human and animal feed, were investigated for their potential for the development of agricultural biotechnology and in the field of human health. In the pine nuts extract, which blocked the activities of cysteine proteases, it was detected potent insecticidal activity against termites () belonging to the most abundant termite genus in tropical regions.

Improving the understanding of plasma kallikrein contribution to arterial thrombus formation using two plant protease inhibitors.

The purpose of antithrombotic therapy is the prevention of thrombus formation and/or its extension with a minimum risk of bleeding. The inhibition of a variety of proteolytic processes, particularly those of the coagulation cascade, has been reported as a property of plant protease inhibitors. The role of trypsin inhibitors (TIs) from Delonix regia (Dr) and Acacia schweinfurthii (As), members of the Kunitz family of protease inhibitors, was investigated on blood coagulation, platelet aggregation, and thrombus formation.

Plasma kallikrein enhances platelet aggregation response by subthreshold doses of ADP.

Human plasma kallikrein (huPK) potentiates platelet responses to subthreshold doses of ADP, although huPK itself, does not induce platelet aggregation. In the present investigation, we observe that huPK pretreatment of platelets potentiates ADP-induced platelet activation by prior proteolysis of the G-protein-coupled receptor PAR-1. The potentiation of ADP-induced platelet activation by huPK is mediated by the integrin αβ through interactions with the KGD/KGE sequence motif in huPK.

Bradykinin release avoids high molecular weight kininogen endocytosis.

Human H-kininogen (120 kDa) plays a role in many pathophysiological processes and interacts with the cell surface through protein receptors and proteoglycans, which mediate H-kininogen endocytosis. In the present work we demonstrate that H-kininogen containing bradykinin domain is internalized and different endogenous kininogenases are present in CHO-K1 cells. We used CHO-K1 (wild type) and CHO-745 (mutant deficient in proteoglycans biosynthesis) cell lines.

The Kallikrein Inhibitor from Bauhinia bauhinioides (BbKI) shows antithrombotic properties in venous and arterial thrombosis models.

The Bauhinia bauhinioides Kallikrein Inhibitor (BbKI) is a Kunitz-type serine peptidase inhibitor of plant origin that has been shown to impair the viability of some tumor cells and to feature a potent inhibitory activity against human and rat plasma kallikrein (Kiapp 2.4 nmol/L and 5.2 nmol/L, respectively).

Bauhinia forficata lectin (BfL) induces cell death and inhibits integrin-mediated adhesion on MCF7 human breast cancer cells.

Background: Plant lectins have attracted great interest in cancer studies due to their antitumor activities. These proteins or glycoproteins specifically and reversibly bind to different types of carbohydrates or glycoproteins. Breast cancer, which presents altered glycosylation of cell surface glycoproteins, is one of the most frequent malignant diseases in women.

Unfolding studies of the cysteine protease baupain, a papain-like enzyme from leaves of Bauhinia forficata: effect of pH, guanidine hydrochloride and temperature.

Baupain belongs to the α+β class of proteins with a secondary structure-content of 44% α-helix, 16% β-sheet and 12% β-turn. The structural transition induced by pH was found to be noncooperative, with no important differences observed in the pH range from 3.0 to 10.

Using a Caesalpinia echinata Lam. protease inhibitor as a tool for studying the roles of neutrophil elastase, cathepsin G and proteinase 3 in pulmonary edema.

Acute lung injury (ALI) is characterized by neutrophil infiltration and the release of proteases, mainly elastase (NE), cathepsin G (Cat G) and proteinase 3 (PR3), which can be controlled by specific endogenous inhibitors. However, inhibitors of these proteases have been isolated from different sources, including plants. For this study, CeEI, or Caesalpinia echinata elastase inhibitor, was purified from C.

The component of Carica papaya seed toxic to A. aegypti and the identification of tegupain, the enzyme that generates it.

As Aedes aegypti transmits the etiologic agents of both yellow and dengue fever; vector control is considered essential to minimise their incidence. The aim of this work was to identify the component of Carica papaya seed toxic to A. aegypti, and the identification of tegupain, the enzyme that generates it.

Blocking the proliferation of human tumor cell lines by peptidase inhibitors from Bauhinia seeds.

In cancer tumors, growth, invasion, and formation of metastasis at a secondary site play a pivotal role, participating in diverse processes in the development of the pathology, such as degradation of extracellular matrix. Bauhinia seeds contain relatively large quantities of peptidase inhibitors, and two Bauhinia inhibitors were obtained in a recombinant form from the Bauhinia bauhinioides species, B. bauhinoides cruzipain inhibitor, which is a cysteine and serine peptidase inhibitor, and B.

A plant Kunitz-type inhibitor mimics bradykinin-induced cytosolic calcium increase and intestinal smooth muscle contraction.

BbKI is a kallikrein inhibitor with a reactive site sequence similar to that of kinins, the vasoactive peptides inserted in kininogen moieties. This structural similarity probably contributes to the strong interaction with plasma kallikrein, the enzyme that releases, from high-molecular weight kininogen (HMWK), the proinflammatory peptide bradykinin, which acts on B(2) receptors (B(2)R). BbKI was examined on smooth muscle contraction and Ca(2+) mobilization, in which the kallikrein-kinin system is involved.

Effects of compounds from Passiflora edulis Sims f. flavicarpa juice on blood coagulation and on proteolytic enzymes.

Passion fruit (Passiflora edulis Sims f. flavicarpa) is popularly known for its sedative and calming properties and is consumed as a fresh fruit or as a juice. The clinical observation of blood incoagulability associated with excessive consumption of passion fruit juice, in a patient treated with warfarin, prompted the current study to investigate in vitro the presence of blood clotting inhibitors in Passiflora edulis Sims f.

Enterolobium contortisiliquum trypsin inhibitor (EcTI), a plant proteinase inhibitor, decreases in vitro cell adhesion and invasion by inhibition of Src protein-focal adhesion kinase (FAK) signaling pathways.

Tumor cell invasion is vital for cancer progression and metastasis. Adhesion, migration, and degradation of the extracellular matrix are important events involved in the establishment of cancer cells at a new site, and therefore molecular targets are sought to inhibit such processes. The effect of a plant proteinase inhibitor, Enterolobium contortisiliquum trypsin inhibitor (EcTI), on the adhesion, migration, and invasion of gastric cancer cells was the focus of this study.

Heparin affects the interaction of kininogen on endothelial cells.

In the plasma kallikrein-kinin system, it has been shown that when plasma prekallikrein (PK) and high molecular weight kininogen (HK) assemble on endothelial cells, plasma kallikrein (huPK) becomes available to cleave HK, releasing bradykinin, a potent mediator of the inflammatory response. Because the formation of soluble glycosaminoglycans occurs concomitantly during the inflammatory processes, the effect of these polysaccharides on the interaction of HK on the cell surface or extracellular matrix (ECM) of two endothelial cell lines (ECV304 and RAEC) was investigated. In the presence of Zn(+2), HK binding to the surface or ECM of RAEC was abolished by heparin; reduced by heparan sulfate, keratan sulfate, chondroitin 4-sulfate or dermatan sulfate; and not affected by chondroitin 6-sulfate.

The effects of a plant proteinase inhibitor from Enterolobium contortisiliquum on human tumor cell lines.

Supplementary to the efficient inhibition of trypsin, chymotrypsin, plasma kallikrein, and plasmin already described by the EcTI inhibitor from Enterolobium contortisiliquum, it also blocks human neutrophil elastase (K(iapp)=4.3 nM) and prevents phorbol ester (PMA)-stimulated activation of matrix metalloproteinase (MMP)-2 probably via interference with membrane-type 1 (MT1)-MMP. Moreover, plasminogen-induced activation of proMMP-9 and processing of active MMP-2 was also inhibited.

Structural and functional properties of kunitz proteinase inhibitors from leguminosae: a mini review.

Seed proteins that inhibit proteinases are classified in families based on amino acid sequence similarity, nature of reactive site and mechanism of action, and are used as tools for investigating proteinases in physiological and pathological events. More recently, the plant Kunitz family of inhibitors with two disulphide bridges was enlarged with members containing variable number of cysteine residues, ranging from no cysteine at all to more than four residues. The characteristic of these proteins, as well the interactions with their target proteinases, are briefly discussed.

Interaction of proteinase inhibitors with phospholipid vesicles is modulated by pH.

rBbKI and rBbCI, plant recombinant inhibitors from Bauhinia bauhinioides, and BpuTI from Bauhinia purpurea seeds distinctly and specifically block proteolytic enzymes. The secondary structures of those inhibitors were compared and their interactions with phospholipid vesicles were evaluated by the release of calcein and by intrinsic fluorescence of tryptophan residues. The results show that rBbKI, rBbCI and BpuTI are able to interact with phospholipd vesicles and induce membrane permeabilization in a concentration- and pH-dependent manner.

A novel subclassification for Kunitz proteinase inhibitors from leguminous seeds.

Kunitz-type trypsin inhibitors from legume seeds have been characterized structurally. The presence of Cys-Cys in single or double chains shows a new pattern of proteins structurally not so closely related to STI. Therefore, briefly, with regard to cysteine content, plant Kunitz proteinase inhibitors may be classified into four groups: no Cys-Cys at all, one, two and more than two Cys residues.

The defensive functions of plant inhibitors are not restricted to insect enzyme inhibition.

Three plant proteinase inhibitors BbKI (kallikrein inhibitor) and BbCI (cruzipain inhibitor) from Bauhinia bauhinioides, and a BrTI (trypsin inhibitor) from B. rufa, were examined for other effects in Callosobruchus maculatus development; of these only BrTI affected bruchid emergence. BrTI and BbKI share 81% identities in their primary sequences and the major differences between them are the regions comprising the RGD and RGE motifs in BrTI.

Action of plant proteinase inhibitors on enzymes of physiopathological importance.

Obtained from leguminous seeds, various plant proteins inhibit animal proteinases, including human, and can be considered for the development of compounds with biological activity. Inhibitors from the Bowman-Birk and plant Kunitz-type family have been characterized by proteinase specificity, primary structure and reactive site. Our group mostly studies the genus Bauhinia, mainly the species bauhinioides, rufa, ungulata and variegata.

Involvement of heparan sulfate proteoglycans in cellular uptake of high molecular weight kininogen.

In this study, we analyzed the influence of proteoglycans on the interaction between human high molecular weight kininogen (HK) and the cell surface. We found that D5- related peptide inhibits HK-biotin cellular uptake. Confocal microscopy showed that HK colocalizes with heparan sulfate proteoglycan (HSPG) at the cell surface.

Crystal structure of a novel cysteinless plant Kunitz-type protease inhibitor.

Bauhinia bauhinioides Cruzipain Inhibitor (BbCI) is a cysteine protease inhibitor highly homologous to plant Kunitz-type inhibitors. However, in contrast to classical Kunitz family inhibitors it lacks cysteine residues and therefore disulfide bridges. BbCI is also distinct in the ability to inactivate enzymes belonging to two different classes, cysteine and serine proteases.

Heparin modulation of human plasma kallikrein on different substrates and inhibitors.

The interplay of different proteases and glycosaminoglycans is able to modulate the activity of the enzymes and to affect their structures. Human plasma kallikrein (huPK) is a proteolytic enzyme involved in intrinsic blood clotting, the kallikrein-kinin system and fibrinolysis. We investigated the effect of heparin on the action, inhibition and secondary structure of huPK.