(Circulation. 1999;100:400-406.)
© 1999 American Heart Association, Inc.
Basic Science Reports |
Matrix Metalloproteinase Inhibitor Prevents Acute Lung Injury After Cardiopulmonary Bypass
From the Departments of Surgery and Cardiovascular Perfusion, SUNY Health Science Center at Syracuse; the Department of Oral Biology and Pathology, SUNY Health Science Center at Stony Brook (N.S.R., L.M.G., S.R.S.); and the Department of Biology, SUNY at Cortland (L.A.G.), NY.
 |
Abstract |
|---|
 Top Abstract IntroductionMethodsResultsDiscussionReferences |
|---|
Background—Acute lung injury (ALI) after cardiopulmonary bypass (CPB) results from sequential priming and activation of neutrophils. Activated neutrophils release neutral serine, elastase, and matrix metalloproteinases (MMPs) and oxygen radical species, which damage alveolar-capillary basement membranes and the extracellular matrix, resulting in an ALI clinically defined as adult respiratory distress syndrome (ARDS). We hypothesized that treatment with a potent MMP and elastase inhibitor, a chemically modified tetracycline (CMT-3), would prevent ALI in our sequential insult model of ALI after CPB.
Methods and Results—Anesthetized Yorkshire pigs were randomized to 1 of 5 groups: control (n=3); CPB (n=5), femoral-femoral hypothermic bypass for 1 hour; LPS (n=7), sham bypass followed by infusion of low-dose Escherichia coli lipopolysaccharide (LPS; 1 µg/kg); CPB+LPS (n=6), both insults; and CPB+LPS+CMT-3 (n=5), both insults plus intravenous CMT-3 dosed to obtain a 25-µmol/L blood concentration. CPB+LPS caused severe lung injury, as demonstrated by a significant fall in PaO2 and an increase in intrapulmonary shunt compared with all groups (P<0.05). These changes were associated with significant pulmonary infiltration of neutrophils and an increase in elastase and MMP-9 activity.
Conclusions—All pathological changes typical of ALI after CPB were prevented by CMT-3. Prevention of lung dysfunction followed an attenuation of both elastase and MMP-2 activity. This study suggests that strategies to combat ARDS should target terminal neutrophil effectors.
Key Words: lung • metalloproteinases • cardiopulmonary bypass
|
Introduction |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
Each year more than 100 000 people die of complications of the adult respiratory distress syndrome (ARDS).1 Despite significant advances in critical care management, mortality from ARDS remains >40%.2 3 4 ARDS after cardiopulmonary bypass (CPB) is often called "postperfusion" or "postpump" syndrome, but it is otherwise indistinguishable from acute lung injury associated with trauma, hemorrhage, or sepsis.
We have previously demonstrated that acute lung injury after CPB can develop after consecutive minor insults, with CPB acting as the initial inflammatory event.5 A short period of CPB alone is rather innocuous, but when it is combined with a subsequent, seemingly benign insult (ie, transient hypoxia, ischemia, endotoxemia), the result is an overwhelming inflammatory response leading to endothelial injury, pulmonary edema, and ARDS. It has been well documented that the lung injury in both ARDS6 7 and specifically postpump syndrome7 8 9 is neutrophil-mediated. Our previous investigations support this concept, because we have shown an association between pulmonary neutrophil sequestration and physiological lung injury.5 Thus, postpump syndrome provides an excellent model of ARDS, since it allows us to investigate the sequence of pathophysiological changes because the timing of the priming and activating stimuli are known.
Activation of sequestered neutrophils leads to the release of proteases
and oxygen radical species. Elevated levels of neutrophil elastase
and matrix metalloproteinases (MMPs) are present in plasma of
patients after CPB10 11 and in both plasma and
bronchoalveolar lavage (BAL) fluid of patients with
ARDS.12 MMPs released from activated neutrophils
degrade type IV collagen, which provides the framework for the basement
membrane of pulmonary capillaries, and interstitial
collagen and proteoglycan.13 14 Aside from direct
collagenolysis, MMPs inactivate endogenous
antiproteases, allowing unrestricted protease activity.15
Studies by Golub et al have confirmed that, by
nonantimicrobial mechanisms, chemically modified tetracyclines (CMTs)
can directly inhibit MMPs and prevent activation of pro-MMPs to MMPs by
scavenging reactive oxygen species.16 This inhibits direct
collagenolysis and protects against inactivation of
endogenous antiproteases. We hypothesized that treatment
with a CMT-3 will attenuate both MMP collagenolytic activity and
MMP-induced inactivation of 
1-protease
inhibitor to prevent basement membrane degradation and
protect against the development of acute lung injury in our porcine
model.
|
Methods |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
Surgical Preparation
Surgical preparation required for our model of acute lung injury after CPB has been described extensively elsewhere.5 Briefly, healthy Yorkshire hybrid pigs (15 to 20 kg) were anesthetized with sodium pentobarbital (50 mg/mL IV bolus, then 6 mg · kg-1 · h-1) and bolus infusion of pancuronium bromide. Instrumentation included a tracheostomy and intravascular catheters to monitor both systemic and pulmonary arterial and venous pressures. Initial ventilator settings were FiO2=50%, tidal volume=12 mL/kg, and rate=10 breaths per minute. Adjustments were made in the respiratory rate to obtain a baseline PaCO2=45 to 55 mm Hg. Heating pads and warmed IV fluids maintained core temperature between 36°C and 38°C. With the exception of measurements while animals were on CPB, all blood gas measurements were made at 37°C. The potential error is pH ±0.01, PCO2 ±2 mm Hg, and PO2 ±5 mm Hg. All groups received lactated Ringer's solution (25 mL · kg-1 · h-1) and bolus infusion of dextran 70 to maintain cardiac output within 10% of baseline.
Cardiopulmonary Bypass
The technique for initiating CPB has been described in detail
elsewhere.5 Briefly, with verification of adequate
anticoagulation (activated clotting time >480 seconds),
femoral cannulas were placed. The pump priming solution consisted of
lactated Ringer's solution (1500 mL), mannitol (5 g), sodium
bicarbonate (35 mEq), and porcine lung heparin (300 U/kg).
Nonpulsatile, hypothermic CPB was initiated at a flow rate of 120 mL/kg
and continued for 1 hour. During weaning, isoproterenol (4 µg/min)
facilitated effective ejection volume to eliminate cardiac distension
and prevent ischemia and/or dysrhythmias. Within 30 minutes,
animals had returned to baseline status, defined as (1) all blood
within the oxygenator transfused back into the animal, (2) heparin
reversed with protamine (1.3 mg/100 U heparin), (3)
normothermic body temperature, and (4) pulmonary
pressures, systemic pressure, and cardiac output all within 10% of
baseline without assistance from inotropic agents. Animals not
randomized to an arm exposed to CPB received sham CPB (surgical
preparation without anticoagulation or bypass).
Endotoxin Infusion
Pigs receiving LPS were infused with 1 µg/kg of
Escherichia coli lipopolysaccharide (LPS; Sigma
111:B4) mixed in 500 mL of saline and delivered over 1 hour via a
volumetric infusion pump (Flo-Guard 8000, Travenol Inc). Pigs
randomized to an arm not exposed to LPS received sham LPS (500 mL
saline vehicle only).
Chemically Modified Tetracycline
CMT-3 (6-demethyl-6-deoxy-4-dedimethylaminotetracycline) is a
chemically modified, nonantibiotic tetracycline with a molecular weight
of 371.35. CMT-3 (Collagenex Pharmaceuticals) was obtained in powder
form, dissolved in dimethyl sulfoxide, and then administered
intravenously at a dose to achieve a blood concentration of
25 µmol/L (9.2 µg/mL). We assumed predominantly intravascular
distribution for our dosing regimen. This method of delivery only
achieved a serum concentration of 1.2±0.367 µg/mL at 1 hour as
determined by high-performance liquid
chromatography.
Calculations
Calculation of venous admixture was performed on an Explorer
cardiac output computer (Baxter Healthcare Corp) by the following
equation: Venous admixture
(Qs/Qt)={100x[(Hgbx1.38)+
(0.0031xPAO2)-CaO2]}/[(Hgbx1.38)+(0.0031xPAO2)-CvO2],
where CaO2 and
CvO2 are arterial and
venous blood oxygen content, Qs is venous
admixture blood flow, Qt is total blood flow, and
PAO2 is the partial pressure of
alveolar oxygen. CaO2,
CvO2, and
PAO2 were calculated by use of the
following equations:
CaO2=(0.0138xHgbx
SaO2)+0.0031xPaO2;
CvO2=(0.0138xHgbxSvO2)+0.0031xPvO2;
and PAO2=
[(PB-PH2O)xFiO2]-PaCO2x[FiO2+(1-FiO2)+0.8].
Arterial (SaO2) and
venous (SvO2) saturations were
measured with the OSM3. Ventilatory efficiency index (VEI) has
been previously validated17 and was calculated with the
equation VEI (mL · kg-1 · cm
H2O-1)=(5 mL ·
kg-1 ·
min-1)/[(
PxRfxPaCO2)/760],
where P is the difference between peak- and end-expiratory pressures
(mm Hg) and Rf is respiratory frequency. The VEI is described in units
analogous to compliance and was calculated assuming that the rate of
total CO2 production was constant at 5
mL · kg-1 ·
min-1 and
PACO2=PaO2.
The index allowed comparison of respiratory status among animals whose
airway pressures, respiratory rates, and
PaCO2 vary throughout the
experiment.
Bronchoalveolar Lavage
At necropsy, the bronchus to the left lower lobe was cannulated
and secured so that it was isolated from the remaining bronchial tree.
Saline (60 mL) was then injected as 3 aliquots of 20 mL each. Each
aliquot was injected quickly and then withdrawn slowly 3 times to
obtain an optimal BAL specimen. Combined aliquots of BAL fluid were
spun at 1000g for 10 minutes to remove cells. Supernatant
was frozen at -70°C for subsequent chemical analysis.
Gelatinase Activity
The methods for purification of collagenase have
been fully described elsewhere.15 Briefly, 100 µL of 1x
collagenase buffer (Tris 0.50 mmol/L, NaCl 0.2 mol/L,
5 mmol/L CaCl2, 0.02% Brij) was added to
900 µL of BAL fluid. Seventy microliters of this mixture plus 10 µL
of 1.0 mmol/L aminophenyl mercuric acetate plus 10 µL of soybean
trypsin inhibitor (300 mg/mL) was incubated at room
temperature for 1 hour. Next, 10 µL of radiolabeled (tritium) type I
rat skin gelatin was added and incubated at 37°C for 4 hours. Then 50
µL of cold gelatin (2 mg/mL) and 100 µL of 45% trichloroacetic
acid were added, and the entire mixture was cooled at 4°C for 30
minutes. The reaction mixture was centrifuged at
13 000g for 15 minutes. A 100-µL aliquot was removed to
determine the amount of radioactivity released into the supernatant by
liquid scintillation counting. Gelatinase activity was determined as %
gelatin lysed=[(DPM in 100 µL supernatant-DPM of the
blank)x2.5]/(DPM in 10 µL substrate). Ten microliters of the
substrate contained 10 µg of the gelatin. By multiplying lysis by the
substrate concentration and dividing by the time of incubation, we were
able to calculate the quantity of substrate degraded per milligram of
protein per hour.
Elastase Activity
Elastase activity was determined by incubating 100 µL of
the BAL fluid and 400 µL of the 1.25 mmol/L specific synthetic
elastase substrate methoxysuccinyl-Ala-Ala-Pro-Val
p-nitroanilide in a 96-well ELISA plate at 37°C for 18
hours. After incubation, the optical density was read at 405 nm.
Data were expressed as nanomoles elastase substrate degraded
per milligram of protein per hour. These methods are described in full
detail elsewhere.18
BAL Protein
BAL protein analysis was based on the Bradford protein
assay (BioRad) with albumin as the standard. Standards ranged
from 70 µg/mL to 1.40 mg/mL. Twenty milliliters of Coomassie blue dye
solution was diluted to 100 mL with saline. Either 100 µL of standard
solution or 100 µL of BAL fluid was added to 5 mL of Coomassie blue
solution, and the optical density was read at 575 nm in a
spectrophotometer. The results were reported as micrograms of protein
per 100 µL of BAL fluids.
Neutrophil Infiltration
At necropsy, the right middle lobe was excised and its bronchus
cannulated. Glutaraldehyde fixative (2.5%,
phosphate-buffered) was slowly instilled until air was no longer
displaced from the bronchus. The lung was immersed in
glutaraldehyde, and additional fixative was infused
with a syringe until airway pressure of the fixative stabilized at
25 mm Hg. The cannula was clamped, and the lobe was stored in
glutaraldehyde at room temperature for 24 hours. One
tissue block from the fixed lobe of each animal was randomly chosen and
processed for routine paraffin sectioning. Ten serial sections 7
µm thick were made, individually mounted, and numbered consecutively.
A random selection of either odd or even sections was stained with
hematoxylin and eosin for histological assessment. On
each of the 5 sections per animal, a randomly placed sampling probe,
consisting of 10 equidistant sampling points each, was established
along the vertical axis. This method avoided overlap of sampling probes
between sections from the same animal. Each area was located with the
vernier scales of the microscope stage and then viewed with x100 oil
immersion through a high-resolution video camera. Areas featuring
bronchi, connective-tissue septa, or blood vessels other than
capillaries were discarded by advancing the stage 0.5 mm along the
vertical axis of the section. This process limited quantification of
neutrophils to the alveoli and interstitium only. Total neutrophil
count was obtained in all focal planes from a sampling area of
6400 µm2.
Lung Water
Representative tissue samples from both lungs
were sharply dissected free of nonparenchymal tissue, with care taken
to avoid contact with the tissue. Samples were placed in a dish and
weighed. The specimen was then oven-dried at 65°C for 24 hours and
reweighed. Lung water was expressed as a ratio of wet to dry weight.
Protocol
See Figure 1
for a schematic. The
control (n=3) group consisted of animals subjected to 1 hour of sham
CPB (surgical preparation without bypass) followed by sham LPS
(infusion of saline vehicle without LPS) and then monitored for 2
hours. Neither heparin nor protamine was given.
|
30 minutes. Next groups were exposed to infusion of either
E coli LPS or sham LPS (infusion of saline vehicle only)
over 60 minutes. Animals were euthanized at 270 minutes (3 hours after
onset of LPS/sham LPS).The CPB (n=4) group consisted of animals subjected to 1 hour of CPB followed by sham LPS infusion and then monitored for 2 hours.
The LPS (n=6) group consisted of animals subjected to 1 hour of sham CPB followed by LPS infusion and monitored for 2 hours. Neither heparin nor protamine was given.
The CPB+LPS (n=6) group consisted of animals subjected to 1 hour of CPB followed by LPS infusion and monitored for 2 hours.
The CPB+LPS+CMT (n=5) group consisted of animals subjected to 1 hour of CPB followed by simultaneous infusion of LPS+CMT and monitored for 2 hours.
Statistics
Differences between physiological
parameters, neutrophil count, and protease activity were
assessed by 1-way ANOVA with Newman-Keuls post hoc analysis for
between-group comparisons and a repeat ANOVA for within-group
comparisons. Mortality rate between groups was analyzed by
Fisher's exact test. All evaluations used a 95% CI.
Animals
Animals were euthanized with an overdose of pentobarbital (90
mg/kg IV). Experiments described in this study were performed in
adherence to the National Institutes of Health guidelines for the use
of experimental animals in research. The protocol was approved by the
Committee for the Humane Use of Animals at our institution.
|
Results |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
Physiological Changes
CPB+LPS was the only group that developed severe physiological lung injury typical of ARDS. Survival in this group was 60% at 270 minutes, compared with 100% in all other groups. Lung injury manifested as a significant fall in arterial oxygenation (Figure 2
), a fall in the VEI (Figure 3), and an increase in venous admixture
(Figure 4). The VEI fell in all groups
subjected to CPB. However, VEI improved in the group treated with CMT,
to remain significantly better than the CPB+LPS group at 270 minutes
(Figure 3). There was a significant, progressive decrease in
cardiac output over time in all groups. Cardiac output was
significantly lower at 60 minutes in groups undergoing CPB because
venous return limited pump flow to 2 L/min. LPS infusion without CMT
treatment caused a significant increase in pulmonary artery
pressure by 150 minutes (Table 1).
No significant change was noted in the pulmonary artery
occlusion pressure for all groups.
|
P<0.05 vs all
groups.
|
|
|
Histological Changes
Neutrophil infiltration into the pulmonary interstitium
and alveoli was significantly greater (P<0.05) after
CPB+LPS (1.8±0.1 neutrophils/6400 µm2),
compared with control (0.7±0.1), CPB (1.5±0.1), LPS (1.2±0.1), and
CPB+LPS+CMT (1.1±0.1). In addition, neutrophil infiltration after CMT
treatment was significantly higher than control levels
(P<0.05), perhaps as a result of treatment being initiated
1 hour after CPB. Histological sections from animals
that received either CPB or LPS were marked by thickened alveolar walls
with greater leukocyte infiltration than in controls (Figure 5). Animals exposed to CPB+LPS exhibited
more extensive leukocyte infiltration and congested blood vessels than
all other groups. These effects were ameliorated by treatment with
CMT-3.
|
Biochemical Changes
BAL analysis demonstrated a significant increase in
elastase and gelatinase (Figure 6)
activity in the CPB+LPS group compared with all other groups. Both
elastase and gelatinase activities were reduced to levels observed
in controls with CMT-3 treatment. Furthermore, total protein in BAL
fluid increased significantly in animals exposed to LPS and increased
still further with CPB+LPS (Table 2).
However, treatment with CMT-3 ablated the increase in BAL protein seen
in the CPB+LPS group (Table 2). Lung water, as determined by the
ratio of wet to dry weight, was highest in the CPB+LPS group but was
not statistically different from all other groups (Table 2).
Lung water in the CPB+LPS group remained insignificantly different
because there was a single animal (1 of 6) that did not demonstrate a
measurable increase in lung water, although gross parenchymal edema was
noted, as with all animals randomized to this group. Repeat
analysis without this animal achieved significance
(P<0.05). Nonetheless, because all other
physiological, histological, and
biochemical parameters for this single animal were as
anticipated for the CPB+LPS group and because no obvious technical
failure was identified, we did not have legitimate reason to exclude
the single poor responder in the results for lung water.
|
|
|
Discussion |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
This study confirms our previous investigations, which have demonstrated that acute lung injury after bypass can be caused by sequential, seemingly innocuous insults.4 5 These findings support the theory that accepts the mechanism of postpump syndrome as a neutrophil-mediated destruction of the alveolar-capillary interface. In our model, CPB primes neutrophils, causing them to sequester in the lung, and subsequent exposure to low-dose LPS activates these primed neutrophils, causing degranulation and the release of oxygen radical species, serine proteases, and MMPs. The CPB+LPS group demonstrated a high-protein pulmonary edema with an insignificant change in pulmonary artery occlusion pressure and a pulmonary artery pressure that increased significantly over time, findings consistent with noncardiogenic pulmonary edema. The process was associated with damage to the pulmonary endothelium, high-permeability edema, and acute lung injury. CMT-3 treatment reduced both elastase and MMP activity, decreased neutrophil infiltration into the pulmonary interstitium, decreased extracapillary extravasation of protein, and prevented the physiological lung dysfunction typical of clinical ARDS.
The CMT-induced reduction of BAL elastase and MMPs could reflect direct inhibition of enzyme, diminution of neutrophil infiltration, inhibition of neutrophil degranulation, or a combination of these possibilities. Treatment with CMT-3 decreased pulmonary neutrophil infiltration compared with CPB+LPS without treatment. Importantly, neutrophil infiltration was reduced only to the level observed in animals that received a single insult (CPB or LPS), a level significantly greater than control. However, CMT treatment completely ablated elastase and MMP activity, with enzyme levels similar to controls at 6 hours. This suggests that prevention of lung injury by CMT was due, in part, to direct enzyme inhibition and not solely to a reduction in neutrophil infiltration.
It is well established that the initial response to a systemic inflammatory stimulus includes sequestration of neutrophils in the pulmonary capillaries and their elaboration of cytokines and enzymes.5 6 7 8 9 Multiple investigators have demonstrated large numbers of neutrophils sequestered in the lung during both ARDS6 and postpump syndrome.5 7 8 9 The local cytokine activity serves to activate sequestered neutrophils, which then secrete numerous mediators. These neutrophil-derived bioactive lipids, cytokines, oxygen metabolites, and granular enzymes all have the capability of injuring basement membranes and the extracellular matrix. Those of greatest importance are toxic oxygen radicals, neutral serine proteases, and MMPs.19 20
Although the progression of neutrophil-mediated lung injury is very complex, it is evident that the destruction of the endothelial basement membrane has a central role.13 14 The basement membrane of the capillary endothelium and the alveolar epithelium is a complex of type IV collagen. MMPs and serine proteases are the primary neutrophil products that can target the basement membrane. Elastase and MMP-9 (92-kDa type IV collagenase) are present in neutrophils and released on activation. It has been shown that the number of neutrophils in the BAL fluid correlates with an increase in MMP-9 levels and that quantities of both MMP-9 and MMP-2 are elevated in the BAL fluid of patients with ARDS.12 In addition, the level of MMPs correlates directly with an increase in the concentration of degradation products from type IV collagen within the basement membrane.12 Our data again support these findings, demonstrating significantly increased activity for both elastase and gelatinase in the BAL fluid of animals exposed to sequential insults.
Oxygen metabolites released during neutrophil activation include
superoxide (O2-), along with
the hydroxyl ion (·OH) and hydrogen peroxide
(H2O2). In the presence of
H2O2 and free chloride,
myeloperoxidase from the neutrophil forms hypochlorous acid (HOCl).
HOCl was initially felt to be directly cytotoxic; however, recent
evidence has demonstrated that HOCl is far less toxic than commonly
assumed. The more important role of HOCl in lung injury may be its
capacity to oxidize 1-protease
inhibitor, an important endogenous
antiprotease. This results in unopposed serine protease activity and
consequent degradation of the basement membrane and the
interstitial matrix.19 20
When devising a plan to prevent or treat acute lung injury after CPB, 4 distinct strategies could be used to protect against neutrophil-mediated injury. First, because neutrophil activation is central to the pathogenesis of ARDS, an obvious approach would be to simply deplete the number of circulating neutrophils. As a prophylactic measure, this strategy is plausible during CPB but is impractical in treatment of all causes of ARDS. As a treatment strategy, this would not be functional, because a large percentage of neutrophils are already sequestered by the time a diagnosis of acute lung injury is made, rendering them impervious to a leukoreduction filter. In addition, pure leukodepletion will inhibit the activity of neutrophils toward humoral immunity and the phagocytic clearance of pathogens.
Another strategy would be to modulate neutrophil surface-receptor binding of mediators or to scavenge the very cytokines and mediators that influence primed neutrophils. A third treatment strategy would be to modulate the signal transduction pathways or the synthesis of mediators within the neutrophil itself. The problem with the latter 2 strategies is that the control of bioactive lipids, cytokines, and cell signal pathways would influence multiple cell lines, not neutrophils alone. In addition, clinical trials using these strategies have had limited success.
A final approach for the treatment of ARDS, investigated in this study,
targets the neutrophil-specific terminal effectors. This strategy
provides a substance (CMT) that antagonizes or neutralizes active
neutrophil-derived mediators, specifically the oxygen metabolites,
serine proteases, and MMPs. In their comprehensive review, Gadek and
Pacht1 determined that ARDS develops from a
protease-mediated destruction of the alveolar-capillary basement
membrane that results from an imbalance in the antioxidant-antiprotease
ratio within the pulmonary parenchyma. Tetracycline-based drugs
have been used as antibacterial agents for decades. Numerous studies
have demonstrated that tetracyclines and their chemically modified,
nonantimicrobial analogues (CMTs) inhibit MMP activity and prevent the
activation of MMP precursors (pro-MMPs) by HOCl.16 21 22 23 24 25
This inhibition of MMPs not only blocks collagenolysis but also
prevents 1-protease inhibitors
from becoming inactivated either directly by MMPs or
indirectly by oxidation from HOCl.26 This results in
preserved antiprotease (antielastase) function, which attenuates
neutrophil elastase activity and further protects the basement
membrane.21
The inflammatory signals that provoke the cascade of events leading to acute lung injury after CPB cannot always be anticipated or prevented. A therapeutic alternative is to treat the downstream, neutrophil-derived effectors. We have isolated the role of enhanced activity of neutrophil-derived serine proteases and MMPs and provided a clear association with the physiological and histological aberrations typical of clinical ARDS. This study strongly suggests that strategies to combat acute lung injury should target the terminal effectors of neutrophil activation. Furthermore, our data confirm that CMT tempers the activity of these neutrophil-derived MMPs and serine proteases. CMTs may provide a useful new therapy for the prevention and treatment of acute lung injury after CPB.
|
Acknowledgments |
|---|
This study was funded in part by a grant from the American Society of Extracorporeal Technology. CMT-3 was donated by CollaGenex Inc. The authors would like to thank Michael Sobel, MD, John D. Halverson, MD, William G. Hammond, MD, and Brad Zerler, PhD for their critical review of the manuscript.
|
Footnotes |
|---|
Reprint requests to David E. Carney, MD, SUNY Health Science Center, Department of Surgery, 750 E Adams St, Syracuse, NY 13210.
Received October 9, 1998; revision received April 7, 1999; accepted April 9, 1999.
|
References |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
1. Gadek JE, Pacht ER. The interdependence of lung antioxidants and antiprotease defense in ARDS. Chest.. 1996;110:273S–277S.
2. Repine JE, Beechler CJ. Neutrophils and adult respiratory distress syndrome: two interlocking perspectives in 1991. Am Rev Respir Dis. 1991;144:251–252.[Medline] [Order article via Infotrieve]
3. Milberg JA, Davis DR, Steinberg KP, Hudson D. Improved survival of patients with acute respiratory distress syndrome (ARDS): 1983–1993. JAMA. 1995:273:306–309.
4. Messent M, Sillivan K, Keogh BF, Morgan CJ, Evans TW. Adult respiratory distress syndrome following cardiopulmonary bypass. Anaesthesia. 1992;47:267–268.[Medline] [Order article via Infotrieve]
5.
Picone AL, Lutz CJ, Finck C, Carney D, Gatto LA,
Paskanik A, Searles B, Snyder K, Nieman GF. Multiple sequential insults
cause post-pump syndrome. Ann Thorac Surg.. 1999;67:978–985.
6.
Rinaldo JE. Mediation of ARDS by leukocytes.
Chest. 1986;89:590–593.
7.
Johnson D, Thomson D, Hurst T, Prasad K, Wilson T,
Murphy F, Saxena A, Mayers I. Neutrophil-mediated acute lung injury
after extracorporeal perfusion. J Thorac Cardiovasc
Surg.. 1994;107:1193–1202.
8.
Tonz M, Mihaljevic T, Von Segesser LK, Fehr J, Schmid
ER, Turina MI. Acute lung injury during cardiopulmonary bypass:
are the neutrophils responsible? Chest. 1995;108:1551–1556.
9. Butler J, Rocker GM, Westaby S. Inflammatory response to cardiopulmonary bypass. Ann Thorac Surg. 1993;55:552–559.[Abstract]
10. Butler J, Pillai R, Rocker GM, Westaby S, Parker D, Shale DJ. Effect of cardiopulmonary bypass on systemic release of neutrophil elastase and tumor necrosis factor. J Thorac Cardiovasc Surg. 1993;105:25–30.[Abstract]
11. Faymonville ME, Pincemail J, Duchateau J, Paulus JM, Adams A, Deby-Dupont G, Deby C, Albert A, Larbuisson R, Limet R, Lamy M. Myeloperoxidase and elastase as markers of leukocyte activation during cardiopulmonary bypass in humans. J Thorac Cardiovasc Surg. 1991;102:309–317.[Abstract]
12. Torii K, Iida KI, Miyazaki Y, Saga S, Konkoh Y, Taniguchi H, Taki F, Takagi K, Mutsushi M, Suzuki R. Higher concentrations of matrix metalloproteinases in bronchoalveolar lavage fluid of patients with adult respiratory distress syndrome. Am J Respir Crit Care Med. 1997;155:43–46.[Abstract]
13.
Kawamura M, Yamasawa F, Ishizaka A, Kato R, Kikuchi K,
Kobayashi K, Aoli T, Sakamaki F, Hasegawa N, Kawashiro T, Ishihara T.
Serum concentration of 7S collagen and prognosis in patients with the
adult respiratory distress syndrome. Thorax. 1994;49:144–146.
14. Suter PM, Suter S, Girardin E, Roux LP, Grau GE, Dayer JM. High bronchoalveolar levels of tumor necrosis factor and its inhibitors, interleukin-1, interferon, and elastase, in patients with adult respiratory distress syndrome after trauma, shock, or sepsis. Am Rev Respir Dis. 1992;145:1016–1022.[Medline] [Order article via Infotrieve]
15. McCroskery PA, Richards JF, Harris ED Jr. Purification and characterization of a collagenase extracted from rabbit tumors. Biochem J.. 1975;182:131–142.
16. Golub LM, Evans RT, McNamara TF, Lee H-M, Ramamurthy NS. A non-antimicrobial tetracycline inhibits gingival matrix metalloproteinase and bone loss in Porphyromonas gingivalis-induced periodontitis in rats. Ann N Y Acad Sci.. 1995;732:96–111.[Medline] [Order article via Infotrieve]
17. Cummings JJ, Suter S, Girardin E, Roux LP, Grau GE, Dayer JM. A controlled clinical comparison of four different surfactant preparations in surfactant-deficient preterm lambs. Am Rev Respir Dis. 1992;145:999–1004.[Medline] [Order article via Infotrieve]
18. Ramamurthy NS, Golub LM. Diabetes increases collagenase activity in extracts of rat gingiva and skin. J Periodontal Res. 1983;17:455–462.
19. Fujishima S, Aikawa N. Neutrophil-mediated tissue injury and its modulation. Intensive Care Med. 1995;21:277–285.[Medline] [Order article via Infotrieve]
20. Weiss SJ. Tissue destruction by neutrophils. N Engl J Med.. 1989;320:365–376.[Medline] [Order article via Infotrieve]
21. Mallya SK, Hall JE, Lee H-M, Roemer EJ, Simon SR, Golub LM. Interaction of matrix metalloproteinases with serine protease inhibitors: new potential roles for matrix metalloproteinase inhibitors. Ann N Y Acad Sci. 1994;732:303–314.[Medline] [Order article via Infotrieve]
22. Golub LM, Sorsa T, Lee H-M, Ciancio S, Sorbi D, Ramamurthy NS, Gruber B, Salo T, Konttinen YT. Doxycycline inhibits neutrophil (PMN)-type matrix metalloproteinases in human adult periodontitis gingiva. J Clin Periodontol.. 1995;2:100–109.
23. Ryan ME, Greenwald RA, Golub LM. Potential of tetracyclines to modify cartilage breakdown in osteoarthritis. Curr Opin Rheumatol.. 1996;8:238–247.[Medline] [Order article via Infotrieve]
24. Ingman T, Sorsa T, Suomalainen K, Halinen S, Lindy O, Lauhio A, Saari H, Konttinen YT, Golub LM. Tetracycline inhibition and the cellular sources of collagenase in gingival crevicular fluid in different periodontal diseases. J Periodontol. 1993;64:82–88. Review.[Medline] [Order article via Infotrieve]
25. Rifkin BR, Vernillo AT, Golub LM. Blocking periodontal disease progression by inhibiting tissue-destructive enzymes: a potential therapeutic role for tetracyclines and their chemically-modified analogs. J Periodontal Res. 1993;64:819–827.
26. Lee H-M, Golub LM, Chan D, Leung M, Schroeder K, Wolff M, Simon SR, Crout R. Alpha-1-proteinase inhibitor in gingival crevicular fluid of humans with adult periodontitis: serpinolytic inhibition by doxycycline. J Periodontal Res. 1997;32:9–19.Acute lung injury (ALI) after cardiopulmonary bypass (CPB) is mediated by neutrophil-derived elastase and matrix metalloproteinases (MMPs). We hypothesized that treatment with CMT-3, an elastase and MMP inhibitor, would prevent ALI in our model. Pigs were randomized to the following groups: control; CPB, bypass only; LPS, E coli lipopolysaccharide (LPS) only; CPB+LPS; or CPB+LPS+CMT-3. CPB+LPS caused a significant fall in PaO2 and histological lung injury. Lung injury was associated with a significant increase in elastase and MMP activity. All pathological changes typical of ALI after CPB were prevented with CMT-3 by an attenuation of elastase and MMP activity.[Medline] [Order article via Infotrieve]
This article has been cited by other articles:
 |
|
 |
|
  R. L. Zemans, S. P. Colgan, and G. P. Downey Transepithelial Migration of Neutrophils: Mechanisms and Implications for Acute Lung Injury Am. J. Respir. Cell Mol. Biol., May 1, 2009; 40(5): 519 - 535. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. M. Albaiceta, A. Gutierrez-Fernandez, D. Parra, A. Astudillo, E. Garcia-Prieto, F. Taboada, and A. Fueyo Lack of matrix metalloproteinase-9 worsens ventilator-induced lung injury Am J Physiol Lung Cell Mol Physiol, March 1, 2008; 294(3): L535 - L543. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K.-K. Lee, H.-Y. Yu, Y.-S. Chen, N.-H. Chi, C.-I Chang, and S.-S. Wang Off-Pump Tricuspid Valve Replacement for Severe Infective Endocarditis Ann. Thorac. Surg., July 1, 2007; 84(1): 309 - 311. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. Geraghty, M. P. Rogan, C. M. Greene, R. M. M. Boxio, T. Poiriert, M. O'Mahony, A. Belaaouaj, S. J. O'Neill, C. C. Taggart, and N. G. McElvaney Neutrophil Elastase Up-Regulates Cathepsin B and Matrix Metalloprotease-2 Expression J. Immunol., May 1, 2007; 178(9): 5871 - 5878. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. H. Kim, M. H. Suk, D. W. Yoon, S. H. Lee, G. Y. Hur, K. H. Jung, H. C. Jeong, S. Y. Lee, S. Y. Lee, I. B. Suh, et al. Inhibition of matrix metalloproteinase-9 prevents neutrophilic inflammation in ventilator-induced lung injury Am J Physiol Lung Cell Mol Physiol, October 1, 2006; 291(4): L580 - L587. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P T G Elkington and J S Friedland Matrix metalloproteinases in destructive pulmonary pathology Thorax, March 1, 2006; 61(3): 259 - 266. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Fujita, Q. Ye, H. Ouchi, E. Harada, I. Inoshima, K. Kuwano, and Y. Nakanishi Doxycycline Attenuated Pulmonary Fibrosis Induced by Bleomycin in Mice Antimicrob. Agents Chemother., February 1, 2006; 50(2): 739 - 743. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L.M. Golub, J.B. Payne, R.A. Reinhardt, and G. Nieman Can Systemic Diseases Co-induce (Not Just Exacerbate) Periodontitis? A Hypothetical "Two-hit" Model Journal of Dental Research, February 1, 2006; 85(2): 102 - 105. [Full Text] [PDF]
|
|
|
|
 |
|
 S. S. Kocer, S. G. Walker, B. Zerler, L. M. Golub, and S. R. Simon Metalloproteinase Inhibitors, Nonantimicrobial Chemically Modified Tetracyclines, and Ilomastat Block Bacillus anthracis Lethal Factor Activity in Viable Cells Infect. Immun., November 1, 2005; 73(11): 7548 - 7557. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Guignabert, L. Taysse, J.-H. Calvet, E. Planus, S. Delamanche, S. Galiacy, and M.-P. d'Ortho Effect of doxycycline on sulfur mustard-induced respiratory lesions in guinea pigs Am J Physiol Lung Cell Mol Physiol, July 1, 2005; 289(1): L67 - L74. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. E. Karaiskos, G. M. Palatianos, C. D. Triantafillou, G. H. Kantidakis, G. M. Astras, E. G. Papadakis, and M. I. Vassili Clinical Effectiveness of Leukocyte Filtration During Cardiopulmonary Bypass in Patients with Chronic Obstructive Pulmonary Disease Ann. Thorac. Surg., October 1, 2004; 78(4): 1339 - 1344. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. H. Kim, S. Y. Lee, S. M. Bak, I. B. Suh, S. Y. Lee, C. Shin, J. J. Shim, K. H. In, K. H. Kang, and S. H. Yoo Effects of matrix metalloproteinase inhibitor on LPS-induced goblet cell metaplasia Am J Physiol Lung Cell Mol Physiol, July 1, 2004; 287(1): L127 - L133. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Bozinovski, J. Jones, S.-J. Beavitt, A. D. Cook, J. A. Hamilton, and G. P. Anderson Innate immune responses to LPS in mouse lung are suppressed and reversed by neutralization of GM-CSF via repression of TLR-4 Am J Physiol Lung Cell Mol Physiol, April 1, 2004; 286(4): L877 - L885. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. L. Martin, B. Z. Moyer, M. C. Pape, B. Starcher, K. J. Leco, and R. A. W. Veldhuizen Negative impact of tissue inhibitor of metalloproteinase-3 null mutation on lung structure and function in response to sepsis Am J Physiol Lung Cell Mol Physiol, December 1, 2003; 285(6): L1222 - L1232. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 I. Mayers, T. Hurst, A. Radomski, D. Johnson, S. Fricker, G. Bridger, B. Cameron, M. Darkes, and M. W. Radomski Increased matrix metalloproteinase activity after canine cardiopulmonary bypass is suppressed by a nitric oxide scavenger J. Thorac. Cardiovasc. Surg., March 1, 2003; 125(3): 661 - 668. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 W. Eichler, J F M. Bechtel, J. Schumacher, J. A Wermelt, K.-F. Klotz, and C. Bartels A rise of MMP-2 and MMP-9 in bronchoalveolar lavage fluid is associated with acute lung injury after cardiopulmonary bypass in a swine model Perfusion, March 1, 2003; 18(2): 107 - 113. [Abstract] [PDF]
|
|
|
|
 |
|
 P. E. Marik Pharmacologic Strategies for the Treatment of Acute Respiratory Distress Syndrome: The Horizon is Getting Closer J Intensive Care Med, November 1, 2002; 17(6): 326 - 328. [PDF]
|
|
|
|
|
|
M. K. Winkler and J. L. Fowlkes Metalloproteinase and growth factor interactions: do they play a role in pulmonary fibrosis? Am J Physiol Lung Cell Mol Physiol, July 1, 2002; 283(1): L1 - L11. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. S.H. Ng, S. Wan, A. P.C. Yim, and A. A. Arifi Pulmonary Dysfunction After Cardiac Surgery* Chest, April 1, 2002; 121(4): 1269 - 1277. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Y. Gushima, K. Ichikado, M. Suga, T. Okamoto, K. Iyonaga, K. Sato, H. Miyakawa, and M. Ando Expression of matrix metalloproteinases in pigs with hyperoxia-induced acute lung injury Eur. Respir. J., November 1, 2001; 18(5): 827 - 837. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
I. Mayers, T. Hurst, L. Puttagunta, A. Radomski, T. Mycyk, G. Sawicki, D. Johnson, and M. W. Radomski Cardiac surgery increases the activity of matrix metalloproteinases and nitric oxide synthase in human hearts J. Thorac. Cardiovasc. Surg., October 1, 2001; 122(4): 746 - 752. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 W. L. LEE and G. P. DOWNEY Leukocyte Elastase . Physiological Functions and Role in Acute Lung Injury Am. J. Respir. Crit. Care Med., September 1, 2001; 164(5): 896 - 904. [Full Text] [PDF]
|
|
|
|
 |
|
 E. E.J.M. Creemers, J. P.M. Cleutjens, J. F.M. Smits, and M. J.A.P. Daemen Matrix Metalloproteinase Inhibition After Myocardial Infarction: A New Approach to Prevent Heart Failure? Circ. Res., August 3, 2001; 89(3): 201 - 210. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. G. Kim, B.-H. Lee, and J. W. Seo Light and electron microscopic analyses for ischaemia-reperfusion lung injury in an ovine cardiopulmonary bypass model Perfusion, May 1, 2001; 16(3): 207 - 214. [Abstract] [PDF]
|
|
|
|
|
|
V. R. Conti Pulmonary Injury After Cardiopulmonary Bypass Chest, January 1, 2001; 119(1): 2 - 4. [Full Text] [PDF]
|
|
|
|
|
|
R. Fernando and R. Chan Anti-inflammatory pre-treatment and the resultant effects of interleukin-10: adjuncts to multi-therapeutical strategies Perfusion, December 1, 2000; 15(6): 501 - 505. [Abstract] [PDF]
|
|
|
|
 |
|
 P. K. Shah Targeting the Proteolytic Arsenal of Neutrophils : A Promising Approach for Postpump Syndrome and ARDS Circulation, July 27, 1999; 100(4): 333 - 334. [Full Text] [PDF]
|
|
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||