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Grzegorz Sawicki

Publications and source records attributed to Grzegorz Sawicki.

At least 19 recordsLinked to original sources
PubMed2006

Growth hormone (GH) receptor knockout mice reveal actions of GH in lung development.

The presence of growth hormone (GH) and GH receptors (GHRs) in the lung suggests it is an autocrine/paracrine target site for pulmonary GH action and/or an endocrine site of pituitary GH action. Roles for GH in lung growth or pulmonary function are, however, uncertain. The possibility that pituitary and/or pulmonary GH have physiological roles in lung development has therefore been investigated in GHR knockout (KO or -/-) mice, using a proteomics approach to determine if an absence of GH-signaling affects the proteome of the developing lung. More than 600 proteins were detected by 2-DE in the lungs of control [GHR (+/+)] and GHR (-/-) mice at the end of the alveolarization period (at day 14 postnatally). Of these, 39 differed significantly in protein content at the p>0.05 level [6 were of higher abundance in the GHR (-/-) group, 33 were of lower abundance] and 17 differed at the p>0.02 level [5 of higher abundance in the GHR (-/-) group, 12 of lower abundance] and 7 were definitively identified by MS. Vimentin, a protein involved in cellular proliferation, was reduced in content by approximately 75% in the lungs of the GHR (-/-) mice. Three proteins involved in oxidative protection [SH3 domain-binding glutamic acid-rich-like protein, peroxiredoxin 6 (Prdx6), and isocitrate dehydrogenase 1] were also of lower content in the GHR (-/-) lungs (by approximately 88%, 81% and 70%, respectively). Prdx6 is also involved in lipid and surfactant metabolism, as is apolipoprotein A-IV, the lung content of which was reduced by approximately 73% in these mice. Proteasome 26S ATPase subunit 4, a protein involved in the non-lysosomal degradation of intracellular proteins, and electron flavoprotein alpha subunit , involved in intracellular metabolism, were also reduced in content in the lungs of the GHR (-/-) mice (by approximately 70% and 49%, respectively). These results therefore suggest that these proteins are normally dependent upon GH signaling, and that GH is normally involved in early lung growth, oxidative protection, lipid and energy metabolism and in proteasomal activity. These roles may reflect endocrine actions of pituitary GH and/or local autocrine/paracrine actions of GH produced within the lung.

Animals↗
PubMed2005

Degradation of myosin light chain in isolated rat hearts subjected to ischemia-reperfusion injury: a new intracellular target for matrix metalloproteinase-2.

BACKGROUND: Matrix metalloproteinase-2 (MMP-2) contributes to cardiac dysfunction resulting from ischemia-reperfusion (I/R) injury. MMP-2 not only remodels the extracellular matrix but also acts intracellularly in I/R by degrading troponin I. Whether other intracellular targets exist for MMP-2 during I/R is unknown. METHODS AND RESULTS: Isolated rat hearts were subjected to 20 minutes of ischemia and 30 minutes of reperfusion. The impaired recovery of mechanical function of the heart was attenuated by the MMP inhibitors o-phenanthroline or doxycycline. Quantitative 2D electrophoresis of homogenates of aerobically perfused hearts (control) or those subjected to I/R injury (in the presence or absence of MMP inhibitors) showed 3 low-molecular-weight proteins with levels that were significantly increased upon I/R injury and normalized to control levels by MMP inhibitors. Mass spectrometry analysis identified all 3 proteins as fragments of myosin light chain 1, which possesses theoretical cleavage recognition sequences for MMP-2 and is rapidly degraded by it in vitro. The association of MMP-2 with the thick myofilament in fractions prepared from I/R hearts was observed with immunogold electron microscopy, gelatin zymography for MMP-2 activity, and immunoprecipitation. MMP-2 was found to cleave myosin light chain 1 between tyrosine 189 and glutamine 190 at the C terminus. CONCLUSIONS: Our results demonstrate that myosin light chain 1 is another novel substrate for MMP-2 in the cardiomyocyte and that its degradation may contribute to contractile dysfunction resulting from I/R injury to the heart.

Amino Acid Sequence↗
PubMed2005

Interaction of keratinocytes and fibroblasts modulates the expression of matrix metalloproteinases-2 and -9 and their inhibitors.

Disruption of epidermal-mesenchymal communication due to a delay in epithelialization, increases the frequency of developing fibrotic conditions in skin. As matrix metalloproteinases-2 (MMP-2) and -9 (MMP-9) are two key enzymes involved in wound healing and tissue remodeling, here we examined the efficacy of keratinocyte-fibroblast interaction on modulation of these enzymes and their inhibitors. The conditioned media derived from keratinocytes and fibroblasts grown in upper and lower chambers of a co-culture system, respectively, were analyzed for MMP-2 and -9. Keratinocyte or fibroblast conditioned medium (FCM) was used as a control. Gelatinolytic activity analyzed by zymography showed that keratinocytes mainly express MMP-9 and to a lesser extent MMP-2; while fibroblasts express only MMP-2. In a co-culture system, the activities of both MMP-2 and MMP-9 markedly increased in conditioned media collected from bottom chambers. These findings were consistent with the level of MMP-2 and MMP-9 measured by Western blot. Using the same experimental setting, the levels of tissue inhibitors of MMPs (TIMPs) secreted by keratinocytes and fibroblasts grown in the same co-culture system were also evaluated. Western blot showed that fibroblasts secrete only TIMP-1 and TIMP-2 whose levels were increased by co-culturing fibroblasts with keratinocytes. In contrary the level of TIMP-3, which was mainly expressed by keratinocytes, increased by co-culturing these cells with fibroblasts. In conclusion, interaction of fibroblast-keratinocyte modulates the levels of MMP-2 and -9 and their inhibitors produced by these cells and this interaction may be critical for a better healing quality at a late stage of the wound healing process.

Cell Communication↗
PubMed2004

MMP-2 and MMP-9 and their tissue inhibitors in the plasma of preterm and term neonates.

Matrix metalloproteinases (MMP) and their tissue inhibitors (TIMP) are involved in a variety of physiologic growth and development and pathophysiologic inflammatory conditions. We hypothesized that 1) MMP-2 and -9 plasma activities and TIMP-1 and -2 plasma concentrations in preterm and term neonates were dependent on the gestational and postnatal age; and 2) the respective MMP and their inhibitors were deranged in the development of bronchopulmonary dysplasia (BPD) and intraventricular hemorrhage (IVH) in preterm neonates. From 1998 to 1999, blood samples were collected from preterm neonates (25-36 wk gestation) with or without BPD and/or IVH as well as from healthy term (37-40 wk gestation) neonates during the first 28 d of life. MMP-2 and MMP-9 plasma activities were measured by zymography; TIMP-1 and TIMP-2 plasma concentrations were determined by ELISA. In neonates without BPD or IVH (n = 50), MMP-2 and MMP-9 plasma activities both appeared to be gestational age dependent, with the highest levels observed in neonates of 33-36 wk gestation. TIMP-1 plasma concentration was highest in term neonates but no gestational difference was found in TIMP-2. Only MMP-9 showed a 50% decrease after d 1 in the first postnatal month. Twelve preterm infants with BPD and/or IVH had significantly lower MMP-2 but higher MMP-9 activity and higher TIMP-1 concentration than those of corresponding neonates without BPD or IVH. These findings show the gestational age-dependent expression of plasma MMP activities and their inhibitors. MMP and TIMP may be involved in the feto-neonatal development and may contribute to the pathogenesis of BPD and/or IVH in critically ill preterm neonates.

Birth Weight↗
PubMed2004

Matrix metalloproteinase-2 (MMP-2) is present in the nucleus of cardiac myocytes and is capable of cleaving poly (ADP-ribose) polymerase (PARP) in vitro.

Matrix metalloproteinases (MMPs) are traditionally known for their role in extracellular matrix remodeling. Increasing evidence reveals several alternative substrates and novel biological roles for these proteases. Recent evidence showed the intracellular localization of MMP-2 within cardiac myocytes, colocalized with troponin I within myofilaments. Here we investigated the presence of MMP-2 in the nucleus of cardiac myocytes using both immunogold electron microscopy and biochemical assays with nuclear extracts. The gelatinase activity found in both human heart and rat liver nuclear extracts was blocked with MMP inhibitors. In addition, the ability of MMP-2 to cleave poly (ADP-ribose) polymerase (PARP) as a substrate was examined as a possible role for MMP-2 in the nucleus. PARP is a nuclear matrix enzyme involved in the repair of DNA strand breaks, which is known to be inactivated by proteolytic cleavage. PARP was susceptible to cleavage by MMP-2 in vitro in a concentration-dependent manner, yielding novel degradation products of ~66 and <45 kDa. The cleavage of PARP by MMP-2 was also blocked by MMP inhibitors. This is the first characterization of MMP-2 within the nucleus and we hereby suggest its possible role in PARP degradation.

Animals↗
PubMed2004

Detection of regional changes in protein levels in the in vivo canine model of acute heart failure following ischemia-reperfusion injury: functional proteomics studies.

In this study, we demonstrate the use of proteomics to detect regional differences in protein levels between the reperfused ischemic zone (IZ) and the nonischemic zone (NIZ) of dog hearts which were subjected to in vivo ischemia-reperfusion injury. Using the two-dimensional gel electrophoresis (2-DE) technique, we identified five proteins that were differentially expressed in the IZ versus NIZ: (1) the alpha subunit of ATP synthase isoform precursor was decreased 1.71-fold; (2) creatine kinase M chain was decreased 1.72-fold; (3) NAD+-isocitrate dehydrogenase, alpha subunit was increased 8.34-fold; (4) ATP synthase D chain, mitochondrial was increased 3.02-fold; (5) ventricular myosin light chain-1 was decreased 2.02-fold. Additionally, we found that the level of actin was decreased 2.6-times in the IZ compared to the NIZ on Western blot analysis but was unchanged on 2-DE.

Actins↗
PubMed2004

Improved balance between TIMP-3 and MMP-9 after regional myocardial ischemia-reperfusion during AT1 receptor blockade.

BACKGROUND: Angiotensin II (AngII) modulates the balance between matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMPs), and AngII type 1 receptor (AT1R) blockers (ARBs) limit left ventricular (LV) dysfunction and remodeling after acute ischemia-reperfusion (IR). Whether ARBs improve TIMP/MMP balance during IR has not been determined. METHODS AND RESULTS: We measured hemodynamics, LV function, MMP-2 and MMP-9, and TIMP-3 and TIMP-4 in the ischemic zone (IZ) and nonischemic zone (NIZ) after in vivo IR (90 minutes anterior ischemia; 120 minutes reperfusion) in 28 dogs that were randomized to sham, IR controls, and IR plus the ARB valsartan. In controls, IR induced LV dysfunction, infarction, and IZ remodeling; increased MMP-9 and decreased TIMP-3 in the IZ compared with the NIZ (low TIMP-3/MMP-9 ratio); and did not change MMP-2 or TIMP-4. Compared with controls, valsartan (1) limited LV dysfunction, infarct size, and IZ remodeling; (2) increased MMP-2 and MMP-9 and TIMP-3 and -4 in the NIZ; and (3) increased TIMP-3 and the TIMP-3/MMP-9 ratio in the IZ, but did not change MMP-2 and TIMP-4. CONCLUSION: Valsartan-induced cardioprotection after IR is associated with enhanced TIMP-3 expression and improved TIMP-3/MMP-9 balance in the in vivo dog model.

Angiotensin II Type 1 Receptor Blockers↗
PubMed2004

AT1 receptor blockade alters metabolic, functional and structural proteins after reperfused myocardial infarction: detection using proteomics.

Angiotensin II (AngII) type 1 receptor (AT1R) blockers (ARBs) limit left ventricular (LV) dysfunction and necrosis after reperfused myocardial infarction (RMI) and proteomics can detect changes in protein levels after injury. We applied proteomics to detect changes in levels of specific protein in the ischemic zone (IZ) and non-ischemic zone (NIZ) of dog hearts after in vivo RMI (90 min of anterior ischemia; 120 min of reperfusion) and treatment with intravenous vehicle (control) and the ARBs valsartan or irbesartan (10 mg/kg) over 30 min before RMI. We also assessed LV function, infarction and apoptosis. Both ARBs limited the RMI-induced LV dysfunction, infarct size and apoptosis. Proteomics detected differential expression of 5 randomly selected proteins in the IZ compared to the NIZ after RMI: decrease in a subunit of ATP synthase isoform precursor (consistent with increased conversion to a subunit under metabolic stress), M chain creatine kinase (consistent with cellular damage) and ventricular myosin light chain-1 (consistent with structural damage and decreased contractility); and increase in NAD+ -isocitrate dehydrogenase (ICDH) and alpha subunit and ATP synthase D chain (mitochondrial, consistent with metabolic dysfunction). Importantly, changes in NAD+ -ICDH and ATP synthase D chain were reversed by ARB therapy. Thus, proteomics can detect regional changes in metabolic, contractile, and structural proteins after RMI and several of these proteins are favorably modified by ARBs, suggesting that they may be novel therapeutic targets.

ATP Synthetase Complexes↗
PubMed2004

[Dislocation after total hip arthroplasty].

From 1997 to 2002 in the Department of Traumatology there had been performed 488 total hip replacements: 334 in men and 454 in women at the age between 20 and 84 (average 63.6). The procedures were performed by 12 surgeons and postero-lateral approach was used. Dislocation was found in 22 patients (4.51%): 14 women and 8 men. Majority of dislocation occurred during first 8 weeks after an operation and 68% of them happened during first 6 weeks. The surgical treatment was necessary in 10 cases (45% of all dislocation): 3 patients had only a surgical reposition and 7 patients had a revision arthroplasty. There was found that most cases of dislocation took place at the age above 81 years. Dislocation occurred 5 times more frequently in patients operated on for a femoral neck fractures then for coxarthrosis. The prosthesis TT1 most often dislocated possibly due to its shape (low Head Neck Ratio). Based on our own experience we find dislocation is a multifactorial complication and precise description of causes is usually very difficult.

Adult↗
PubMed2003

Imbalance between tissue inhibitor of metalloproteinase-4 and matrix metalloproteinases during acute myocardial [correction of myoctardial] ischemia-reperfusion injury.

BACKGROUND: We have previously reported that matrix metalloproteinase-2 (MMP-2) contributes to myocardial ischemia-reperfusion injury by degradation of troponin I, a regulatory element of the contractile proteins. MMP activities are also tightly regulated by tissue inhibitors of metalloproteinase (TIMPs). The change in TIMPs during acute myocardial ischemia-reperfusion injury is not clear. METHODS AND RESULTS: Isolated rat hearts were perfused either aerobically for 75 minutes or subjected to 15, 20, or 25 minutes of global, no-flow ischemia followed by 30 minutes of aerobic reperfusion. During reperfusion after ischemia, there was a rapid, enhanced release of TIMP-4, the most abundant TIMP in the heart, into the coronary effluent, as shown both by reverse zymography and Western blot. There was a negative correlation between the recovery of cardiac mechanical function and the release of TIMP-4 during reperfusion in hearts subjected to different durations of ischemia. Immunogold electron microscopy revealed a close association of TIMP-4 with the sarcomeres in aerobically perfused hearts. Moreover, TIMP-4 was present only in thin myofilaments prepared from aerobically perfused hearts but not in ischemic-reperfused hearts. An enhanced MMP activity was shown in ischemic-reperfused hearts by in situ zymography. CONCLUSIONS: Loss of TIMP-4 from the cardiac myocyte leads to an increase in net myocardial MMP activity that contributes to acute myocardial stunning injury.

Actin Cytoskeleton↗
PubMed2003

Functional proteomics of neurokinin B in the placenta indicates a novel role in regulating cytotrophoblast antioxidant defences.

Neurokinin B (NKB) has recently been demonstrated to be secreted from the placenta in abnormally high amounts in preeclampsia (PE) and to cause hypertension in rats, suggesting it may be a mediator of some pathophysiological features of PE. It is also known that NKB receptors exist in the placenta. To determine the effect of high levels of NKB on the placenta, we have performed proteomics on five separate preparations of cultured purified human term cytotrophoblast cells. The results showed a statistically significant decrease in 20 proteins, of which five were unknown proteins. Proteins important in antioxidant defenses that decreased were thioredoxin, cyclophilin A, cytokeratin 1, and peroxiredoxin 5. Two proteins that inhibit intravascular anticoagulation, cytokeratin 1 and annexin 11 were also decreased. Pathways involving pro-inflammatory cytokine activation of NF-kappa B are opposed by Raf kinase inhibitor protein, which was also decreased. Cofilin 1, a protein involved in defense against bacteria, was also decreased. Among other proteins that were suppressed by NKB were proteasome proteins, desmoplakin, and calgizzarin. Western blots confirmed the decrease in cytokeratin 1 and cyclophilin A protein after NKB exposure. In PE, there is reduced antioxidant activity and increased intravascular coagulation. The findings that high levels of NKB, similar to those observed in PE, can impair these two classes of activity support the hypothesis that high NKB levels may contribute to the pathogenesis of PE.

Annexins↗
PubMed2003

Matrix metalloproteinase-2 mediates cytokine-induced myocardial contractile dysfunction.

OBJECTIVE: Pro-inflammatory cytokines depress myocardial contractile function by enhancing peroxynitrite production, yet the mechanism by which peroxynitrite does this is unknown. As matrix metalloproteinases (MMPs) can be activated by peroxynitrite and can proteolytically cleave troponin I in hearts, we determined whether this occurs in cytokine-induced myocardial dysfunction. METHODS: Isolated working rat hearts were perfused with buffer containing interleukin-1 beta, interferon-gamma, and tumor necrosis factor-alpha. RESULTS: Cytokines induced a marked decline in mechanical function during 60-120 min of perfusion. This decline was accompanied by increased myocardial inducible NO synthase activity and perfusate dityrosine (a marker of peroxynitrite), compared to control hearts. Before the decline in mechanical function there was enhanced MMP-2 activity in the perfusate. This was accompanied by decreased tissue levels of MMP-2, tissue inhibitor of matrix metalloproteinases-4 and troponin I in cytokine-treated hearts. The collagen content of the heart was not affected by cytokine treatment. A neutralizing anti-MMP-2 antibody or the MMP inhibitors Ro31-9790 or PD166793 attenuated the decline in myocardial function. Moreover, the MMP-2 antibody prevented the decline in myocardial MMP-2 and troponin I levels. CONCLUSIONS: Myocardial contractile dysfunction caused by pro-inflammatory cytokines results in MMP-2 activation and a decline in tissue inhibitor of matrix metalloproteinases-4 in the heart. Troponin I is also a target for the proteolytic action of MMP-2 during acute heart failure triggered by pro-inflammatory cytokines. Inhibition of MMPs may be a novel pharmacological strategy for the treatment of acute inflammatory heart disease.

Animals↗
PubMed2003

[Bipolar radial head prosthesis--own design].

The authors describe its own design--bipolar radial head prosthesis. The value of this prosthesis is analyzed. The early results in 10 patients, age 20-69 (average 36 years), 7 male and 3 female have been reported. The results are excellent and good. The authors conclude that this prosthesis should be used as an alternative for radial head resection.

Adult↗
PubMed2003

[Total elbow arthroplasty].

The authors describe indications and contraindications for total elbow arthroplasty. The brief characteristic of total elbow replacement is done. The authors describe its own case of clinical use of the Coonrad-Morrey implant.

Arthroplasty, Replacement↗
PubMed2003

[The value of laser Doppler examination of differential diagnosis of the Sudeck syndrome with local osteoporosis after tibia fracture].

The fractures of the shaft of the tibia were analyzed in 120 cases. The level of the osteoporosis in the radiological examination was assessed in comparison to the healthy limb. Osteoporosis was recorded in 60.6% of the cases. The clinical symptoms of the Sudeck syndrome was recorded in 11.25% of the cases. The Laser-Doppler examination was carried out in 120 cases. A standard 3 points measurement was employed: the apex of the toe, the flexion-dorsal part of the foot, and the medial part of the mid tibia length. The examination was done comparatively on both limbs. The pressure used in the occlusion, was 100 mm Hg higher than the pressure on the humeral artery. A faster and higher amplitude post-occlusion circulation reaction in the affected limb, among the patients with an early stage of the clinically diagnosed Sudeck syndrome had been recorded. The outcome is significant statistically. The Laser-Doppler measurement of the microcirculation is a new method and definite conclusions must be draw with caution. However, these results encourage further research.

Diagnosis, Differential↗
PubMed2002

Intracellular action of matrix metalloproteinase-2 accounts for acute myocardial ischemia and reperfusion injury.

BACKGROUND: Matrix metalloproteinases are best recognized for their ability to degrade the extracellular matrix in both physiological and pathological conditions. However, recent findings indicate that some of them are also involved in mediating acute processes such as platelet aggregation and vascular tone. The acute contractile defect of the heart after ischemia-reperfusion may involve the proteolytic degradation of the thin filament protein troponin I; however, the protease responsible for this remains obscure. METHODS AND RESULTS: Here we report that matrix metalloproteinase-2 is colocalized with troponin I within the thin myofilaments of cardiomyocytes in ischemic-reperfused hearts and that troponin I is a novel intracellular target for proteolytic cleavage by matrix metalloproteinase-2. Inhibition of matrix metalloproteinase-2 activity prevented ischemia-reperfusion-induced troponin I degradation and improved the recovery of mechanical function of the heart. CONCLUSIONS: These data reveal for the first time a novel molecular mechanism by which matrix metalloproteinase-2 causes acute myocardial dysfunction after ischemia-reperfusion-injury and that matrix metalloproteinase-2 has a biological action within the cell.

Actin Cytoskeleton↗
PubMed2002

Peroxynitrite-induced myocardial injury is mediated through matrix metalloproteinase-2.

OBJECTIVES: Peroxynitrite (ONOO(-)) mediates in part both ischemia-reperfusion and pro-inflammatory cytokine-induced injury to the heart. As oxidants like ONOO(-) are known to activate matrix metalloproteinases (MMPs), we examined whether they play a role in the detrimental action of ONOO(-) in isolated perfused rat hearts. METHODS: Hearts were isolated from Sprague-Dawley rats and perfused retrogradely with Krebs-Henseleit buffer under constant flow. Peroxynitrite (30 and 80 microM) was infused into the hearts for 15 min. The release of MMPs into the coronary effluent and level of MMPs in the myocardium were measured by gelatin zymography. RESULTS: The main gelatinolytic activity in control effluent was 72-kDa corresponding to pro-MMP-2. Infusion of ONOO(-) (80 microM) for 15 min caused a vasodilatation which peaked at 5 min and then converted into vasoconstriction by 15 min. It also caused a rapid increase in the release of 72-kDa activity within 10 min and a progressive decline in cardiac mechanical function. In contrast, decomposed ONOO(-) caused no change in vascular tone, the release of 72-kDa activity or mechanical function. The MMPs inhibitor PD-166793 prevented the ONOO(-)-induced loss in myocardial mechanical function. Detoxification of ONOO(-) with glutathione prevented both the enhancement in coronary effluent 72-kDa activity and the decline in mechanical function. CONCLUSIONS: Acute cardiac toxicity induced by ONOO(-) is mediated by MMP-2.

Analysis of Variance↗