The in vitro inhibition of human neutrophil elastase activity by some Yemeni medicinal plants

1. Antileucoprotease, being sensitive to oxidative inactivation, can be produced by recombinant techniques. Via site-directed mutagenesis, two mutants of recombinant antileucoprotease were produced in which one or more of the oxidation-sensitive methionine residues were replaced by leucine: in rALP242, methionine-73 was replaced by leucine, and in rALP231, leucine was substituted for four methionine residues. In vitro, native antileucoprotease and the recombinant antileucoprotease preparations have similar inhibitory characteristics towards human neutrophil elastase. We hypothesized that replacement of methionine residues in the antileucoprotease molecule would result in a reduced oxidation sensitivity of the mutants. 2. After incubation of recombinant antileucoprotease and its mutants with increasing dosages of cis-platinum(II)diammine dichloride, we observed that native antileucoprotease and recombinant antileucoprotease were inactivated by this reagent to the same extent. Compared with this, rALP242 was less inactivated, whereas the inhibitory capacity of rALP231 was not influenced by cis-platinum(II)diammine dichloride at all. 3. After incubation of recombinant antileucoprotease, rALP242 and rALP231 with triggered polymorphonuclear leucocytes, which are thought to produce an excess of oxidants, we measured residual inhibitory activities towards human neutrophil elastase of 10%, 55% and 87%, respectively. 4. In vivo, the inhibitory effects of intratracheally administered rALP242 and rALP231 towards human-neutrophil-elastase-induced emphysema were significantly greater than that of recombinant antileucoprotease. There were no significant differences between the mutants. With respect to secretory cell metaplasia and haemorrhage, rALP231 tended to be a better inhibitor than recombinant antileucoprotease and rALP242. 5. We conclude that the recombinant antileucoprotease mutants are less sensitive to oxidation and consequently inhibit human-neutrophil-elastase-induced emphysema to a greater extent than recombinant antileucoprotease.

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Scutellarin Attenuates Human-Neutrophil-Elastase-Induced Mucus Production by Inhibiting the PKC-ERK Signaling Pathway in Vitro and in Vivo

The American Journal of Chinese Medicine ◽

10.1142/s0192415x11009494 ◽

2011 ◽

Vol 39 (06) ◽

pp. 1193-1206 ◽

Cited By ~ 10

Author(s):

De-Peng Jiang ◽

Qi Li ◽

Jie Yang ◽

Juliy M. Perelman ◽

Victor P. Kolosov ◽

...

Keyword(s):

Signaling Pathway ◽

Neutrophil Elastase ◽

Human Neutrophil ◽

Erk Signaling ◽

Control Group ◽

Human Neutrophil Elastase ◽

Dependent Manner ◽

Mucus Production

The aim of this study was to investigate the influence of scutellarin on mucus production induced by human neutrophil elastase (HNE) and the possible in vitro and in vivo mechanisms. To this purpose, cells were incubated with saline, scutellarin or gefitinib for 60 min and exposed to 0.1 μM HNE for 24 h. After being pretreated respectively with saline, scutellarin or gefitinib, rats were challenged intratracheally with HNE by means of nebulization for 30 days. The expression of mucin (MUC) 5AC, protein kinase C (PKC), and extracellular signal-regulated kinase 1/2 (ERK1/2) was assessed by ELISA, RT-PCR or Western blotting. The results showed that scutellarin inhibited MUC5AC mRNA and protein expressions induced by HNE in a concentration-dependent manner in vitro. In the in vivo model, scutellarin significantly attenuated MUC5AC mRNA expression and goblet cell hyperplasia in rats treated with HNE for 30 days, as well as decreased the phosporylation of PKC and ERK1/2 compared to the HNE control group. Therefore, our study showed that scutellarin could prevent mucus hypersecretion by inhibiting the PKC-ERK signaling pathway. Inhalation scutellarin may be valuable in the treatment of chronic inflammatory lung disease.

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Effects of human neutrophil elastase (HNE) on neutrophil function in vitro and in inflamed microvessels

Blood ◽

10.1182/blood.v82.7.2188.2188 ◽

1993 ◽

Vol 82 (7) ◽

pp. 2188-2195 ◽

Cited By ~ 45

Author(s):

RC Woodman ◽

PH Reinhardt ◽

S Kanwar ◽

FL Johnston ◽

P Kubes

Keyword(s):

Neutrophil Elastase ◽

Human Neutrophil ◽

Neutrophil Migration ◽

Specific Inhibitor ◽

Neutrophil Infiltration ◽

Cathepsin G ◽

Neutrophil Adhesion ◽

Human Neutrophil Elastase

Abstract The primary objective of this study was to test the hypothesis that human neutrophil elastase (HNE) affects neutrophil infiltration (adhesion and emigration) into inflamed vessels. To determine whether HNE contributes to neutrophil adhesion in vivo, intravital microscopy was used to study neutrophil-endothelial cell interactions in single inflamed postcapillary venules. Superfusion of platelet-activating factor (PAF) (100 nmol/L) onto the mesentery caused an increase in neutrophil-neutrophil interactions, neutrophil adhesion to postcapillary venules, and cellular emigration out of the vasculature. Both L658 758 (an elastase-specific inhibitor), and Eglin C (an elastase and cathepsin G inhibitor) significantly attenuated all of these parameters in vivo. To further characterize the mechanism(s) involved, various in vitro parameters were assessed. HNE, but not trypsin, caused a dose-dependent (0.01 to 1.0 microgram/mL) increase in the expression of the beta subunit (CD18) of the CD11/CD18 adhesive glycoprotein complex on neutrophils. An HNE-dependent increase in CD11b expression was also observed; however, HNE did not affect the expression of other neutrophil adhesion molecules (L-selectin), superoxide production, or degranulation. PAF-enhanced CD18 expression on neutrophils and neutrophil migration were both abolished by L658 758 but PAF-induced neutrophil adhesion to endothelial monolayers was not affected by the antiproteinase. The in vitro data suggest that the antiproteinases do not directly prevent neutrophil adhesion in vivo but may be important in other CD18-dependent events such as neutrophil- neutrophil interaction or neutrophil infiltration (chemotaxis). These results translate into an important, rate-limiting role for elastase in the process of leukocyte infiltration and accumulation in inflamed microvessels.

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Characterization of Total Phenolic Constituents from the Stems of Spatholobus suberectus Using LC-DAD-MSn and Their Inhibitory Effect on Human Neutrophil Elastase Activity

Molecules ◽

10.3390/molecules18077549 ◽

2013 ◽

Vol 18 (7) ◽

pp. 7549-7556 ◽

Cited By ~ 21

Author(s):

Youwu Huang ◽

Liang Chen ◽

Li Feng ◽

Fujiang Guo ◽

Yiming Li

Keyword(s):

Neutrophil Elastase ◽

Human Neutrophil ◽

Inhibitory Effect ◽

Total Phenolic ◽

Human Neutrophil Elastase ◽

Elastase Activity ◽

Phenolic Constituents ◽

Spatholobus Suberectus

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Further Sesquiterpene Lactones from Viguiera robusta and the Potential Anti-Inflammatory Activity of a Heliangolide: Inhibition of Human Neutrophil Elastase Release

Zeitschrift für Naturforschung C ◽

10.1515/znc-2008-7-811 ◽

2008 ◽

Vol 63 (7-8) ◽

pp. 533-538 ◽

Cited By ~ 17

Author(s):

Nilton S. Arakawa ◽

Karin Schorr ◽

Sérgio R. Ambrósio ◽

Irmgard Merfort ◽

Fernando B. Da Costa

Keyword(s):

Neutrophil Elastase ◽

Human Neutrophil ◽

Sesquiterpene Lactones ◽

Human Neutrophil Elastase ◽

Reference Drug ◽

Aggregation Factor ◽

Anti Inflammatory ◽

Isolated Compound

In addition to known heliangolides, a new eudesmanolide was isolated from the leaf rinse extract of Viguiera robusta (Asteraceae). Structural elucidation was based on spectral analysis. It is the first report on eudesmanolides in members of the subgenus Calanticaria of Viguiera. In this work, the main isolated compound, the furanoheliangolide budlein A, besides its previously reported in vitro and in vivo anti-inflammatory activities, inhibited human neutrophil elastase release. The inhibition was at the concentration of (16.83± 1.96) μm for formylated bacterial tripeptide (fMLP) stimulation and (11.84±1.62) μm for platelet aggregation factor (PAF) stimulation, being slightly less active than the reference drug parthenolide. The results are important to demonstrate the potential anti-inflammatory activities of sesquiterpene lactones and corroborate the previous studies using other targets.

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