Identification of Magnolia officinalis L. Bark Extract as the Most Potent Anti-Inflammatory of Four Plant Extracts

2013 ◽  
Vol 41 (03) ◽  
pp. 531-544 ◽  
Author(s):  
Joel M. Walker ◽  
Amarnath Maitra ◽  
Jessica Walker ◽  
Miriam M. Ehrnhoefer-Ressler ◽  
Taichi Inui ◽  
...  

This study was designed to compare the anti-inflammatory potential of a Magnolia officinalis L. bark extract solely or in combination with extracts prepared from either Polygonum aviculare L., Sambucus nigra L., or Isodon japonicus L. in bacterial lipopolysaccharide (LPS) stimulated human gingival fibroblasts (HGF-1) and human U-937 monocytes, as cell models of periodontal disease. HGF-1 and U-937 cells were incubated with LPS from either Porphyromonas gingivalis or Escherichia coli together with the four plant extracts alone or in combination. Secretion of anti-inflammatory cytokines from HGF-1 and U-937 cells was measured by means of a multiplexed bead assay system. Magnolia officinalis L. bark extract, at concentrations of 1 μg/mL and 10 μg/mL, reduced interleukin 6 (IL-6) and interleukin-8 (IL-8) secretion from HGF-1 cells to 72.5 ± 28.6% and reduced matrix metalloproteinase 2 (MMP-2) and matrix metalloproteinase 9 (MMP-9) secretion from U-937 cells to 8.87 ± 7.97% compared to LPS-treated cells (100%). The other three extracts also reduced secretion of these inflammatory markers but were not as effective. Combination of 9 μg/mL Magnolia officinalis L. extract with 1 μg/mL of each of the other extracts maintained the anti-inflammatory effect of Magnolia officinalis L. extract. Combination of 5 μg/mL Magnolia officinalis L. extract with 5 μg/mL Isodon japonicus L. extract also maintained the anti-inflammatory potential of the Magnolia officinalis L. extract, whereas increasing concentrations of any of the other plant extracts in the combination experiments reduced the Magnolia officinalis L. extract efficacy in U-937 cells.

2021 ◽  
Vol 10 (5) ◽  
Author(s):  
Corey S. Moran ◽  
Erik Biros ◽  
Smriti M. Krishna ◽  
Susan K. Morton ◽  
Daniel J. Sexton ◽  
...  

Background Abdominal aortic aneurysm (AAA) is an important cause of mortality in older adults. The kinin B2 receptor agonist, bradykinin, has been implicated in AAA pathogenesis through promoting inflammation. Bradykinin is generated from high‐ and low‐molecular‐weight kininogen by the serine protease kallikrein‐1. The aims of this study were first to examine the effect of neutralizing kallikrein‐1 on AAA development in a mouse model and second to test how blocking kallikrein‐1 affected cyclooxygenase‐2 and prostaglandin E 2 in human AAA explants. Methods and Results Neutralization of kallikrein‐1 in apolipoprotein E‐deficient ( ApoE −/− ) mice via administration of a blocking antibody inhibited suprarenal aorta expansion in response to angiotensin (Ang) II infusion. Kallikrein‐1 neutralization decreased suprarenal aorta concentrations of bradykinin and prostaglandin E 2 and reduced cyclooxygenase‐2 activity. Kallikrein‐1 neutralization also decreased protein kinase B and extracellular signal‐regulated kinase 1/2 phosphorylation and reduced levels of active matrix metalloproteinase 2 and matrix metalloproteinase 9. Kallikrein‐1 blocking antibody reduced levels of cyclooxygenase‐2 and secretion of prostaglandin E 2 and active matrix metalloproteinase 2 and matrix metalloproteinase 9 from human AAA explants and vascular smooth muscle cells exposed to activated neutrophils. Conclusions These findings suggest that kallikrein‐1 neutralization could be a treatment target for AAA.


1995 ◽  
Vol 308 (2) ◽  
pp. 645-651 ◽  
Author(s):  
Y Itoh ◽  
S Binner ◽  
H Nagase

Tissue inhibitor of metalloproteinases (TIMP)-2 forms a noncovalent complex with the precursor of matrix metalloproteinase 2 (proMMP-2, progelatinase A) through interaction of the C-terminal domain of each molecule. We have isolated the proMMP-2-TIMP-2 complex from the medium of human uterine cervical fibroblasts and investigated the processes involved in its activation by 4-aminophenylmercuric acetate (APMA). The treatment of the complex with APMA-activated proMMP-2 by disrupting the Cys73-Zn2+ interaction of the zymogen. This is triggered by perturbation of the proMMP-2 molecule, but not by the reaction of the SH group of Cys73 with APMA. The ‘activated’ proMMP-2 (proMMP-2*) formed a new complex with TIMP-2 by binding to the N-terminal inhibitory domain of the inhibitor without processing the propeptide. Thus the APMA-treated proMMP-2*-TIMP-2 complex exhibited no gelatinolytic activity. In the presence of a small amount of free MMP-2, however, proMMP-2* in the complex was converted into the 65 kDa MMP-2 by proteolytic attack of MMP-2, but the complex did not exhibit gelatinolytic activity. The gelatinolytic activity detected after APMA treatment was solely derived from the activation of free proMMP-2. The removal of the propeptide of the proMMP-2* bound to TIMP-2 was also observed by MMP-3 (stromelysin 1), but not by MMP-1 (interstitial collagenase). MMP-3 cleaved the Asn80-Tyr81 bond of proMMP-2*. On the other hand, when MMP-3 was incubated with the proMMP-2-TIMP-2 complex, it bound to TIMP-2 and rendered proMMP-2 readily activatable by APMA. These results indicate that the blockage of TIMP-2 of the complex with an active MMP is essential for the activation of proMMP-2 when it is complexed with TIMP-2.


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