Myocarditis following adeno-associated viral gene expression of human soluble TNF receptor (TNFRII-Fc) in baboon hearts.

Sequestration of tumor necrosis factor-alpha (TNFalpha) by TNF-receptor immunoglobulin G (IgG)-Fc fusion proteins can limit heart failure progression in rodent models. In this study we directly injected an adeno-associated viruses (AAV)-2 construct encoding a human TNF receptor II IgG-Fc fusion protein (AAV-TNFRII-Fc) into healthy baboon hearts and assessed virally encoded gene expression and clinical response. Adult baboons received direct cardiac injections of AAV-TNFRII-Fc ( approximately 5 x 10(12) viral/genomes/baboon) or an equivalent dose of AAV-2 empty capsids, and were analyzed after 5 or 12 weeks. Viral genomes were restricted to the myocardium, and routine analyses (blood cell counts, clinical chemistries) remained unremarkable. Echocardiograms were unchanged but electrocardiograms revealed marked ST- and T-wave changes consistent with myocarditis only in baboons receiving AAV-TNFRII-Fc. TNFRII serum levels peaked at approximately 3 times the baseline levels at 1-2 weeks postinjection and subsequently declined to baseline levels. TNFRII-Fc protein and transcripts were detected in the heart at harvest. After AAV injection, anti-AAV-2 antibody levels increased in all baboons, while anti-TNFRII-Fc could not be detected. Baboons that received AAV-TNFRII-Fc developed myocardial infiltrates including CD8+ cells. Thus, a cellular immune response to cardiac delivery of AAV encoding foreign proteins may be an important consideration for AAV-based cardiac gene therapy.

Differential effects of overexpression of two forms of ephrin-A5 on neonatal rat cardiomyocytes.

Eph receptors constitute the largest family of receptor tyrosine kinases. Multiple transcripts of ephrin-A5, the cognate ligand of the EphA3 receptor, were found in neonatal rat cardiomyocytes. Two cDNA clones encoding the full-length ephrin-A5 (ephrin-A5 alpha) and a 27-amino acid deletion form (ephrin-A5 beta) were isolated. To examine the role of ephrin-A5 in cardiomyocytes, the cDNAs were inserted into adenoviral vectors, termed Ad.ephrin-A5 alpha and Ad.ephrin-A5 beta, respectively, and overexpressed in cardiomyocytes. The effect of ephrin-A5 on cardiomyocyte gene expression was investigated using a cDNA expression array and Western blot analysis. The results showed that both ephrin-A5 alpha and ephrin-A5 beta downregulated cyclin D2, cyclin-dependent kinase-4 proteins, and their cognate receptor EphA3, which were associated with reduced bromodeoxyuridine incorporation in cardiomyocytes. Whereas ephrin-A5 alpha and ephrin-A5 beta also induced differential gene expression, only ephrin-A5 beta significantly upregulated the transcription of brain natriuretic peptide and downregulated ras-related protein RAB2, protein kinase C inhibitor protein-1, clusterin, and insulin-like growth factor-binding protein. The results suggest that the two forms of ephrin-A5 share similar function while differ in regulating different sets of genes in cardiomyocytes.

Anti-tumor necrosis factor-alpha antibody limits heart failure in a transgenic model.

BACKGROUND: - Tumor necrosis factor (TNF)-alpha has been implicated in the pathophysiology of congestive heart failure. A strain of transgenic mice (TNF1.6) with cardiac-specific overexpression of TNF-alpha develop congestive heart failure. METHODS AND RESULTS: To determine the effect of anti-TNF-alpha therapy in this model, we studied 3 groups: TNF1.6 mice treated with saline, wild-type mice treated with saline, and TNF1.6 mice treated with TNF-alpha neutralizing antibody (cV1q) from 6 to 12 weeks of age. We used echocardiography to compare cardiac hypertrophy, function, and catecholamine response at 12 weeks of age versus baseline (6 weeks). cV1q treatment did not limit cardiac hypertrophy, but it significantly improved basal fractional shortening and responsiveness to beta-adrenergic stimulation, and it limited development of cardiac dilation. CONCLUSIONS: Blockade of TNF-alpha bioactivity by antibody therapy may both preserve cardiac function and partially reverse pathological changes in congestive heart failure.

Downregulation of matrix metalloproteinases and reduction in collagen damage in the failing human heart after support with left ventricular assist devices.

BACKGROUND: Left ventricular assist device (LVAD) support of the failing heart induces salutary changes in myocardial structure and function. Matrix metalloproteinases (MMPs) are increased in the failing heart and are induced by stretch in cardiac cells in vitro. We hypothesized that mechanical unloading may affect LV plasticity by regulating MMPs and their substrates. METHODS AND RESULTS: LV samples were collected from patients with dilated cardiomyopathy (DCM, n=14) or ischemic cardiomyopathy (ICM, n=16) at the time of implantation of the LVAD and again during cardiac transplantation. MMP-1, -3, and -9 were measured by ELISA, MMP-2 and -9 gelatinolytic activity by gelatin zymography, and tissue inhibitors of metalloproteinases (TIMPs) by Western blot. Total soluble and insoluble collagens were separated by pepsin solubilization, and the contents were determined by quantification of hydroxyproline. The undenatured soluble collagen was measured by Sircol collagen assay. The results showed that MMP-1 and -9 were decreased, whereas TIMP-1 and -3 were increased, but there was no change in MMP-2 and -3 and TIMP-2 and -4 after LVAD support. The undenatured collagen was increased, with the ratio of undenatured to total soluble collagens increased in ICM and that of insoluble to total soluble collagens increased in DCM after LVAD support. CONCLUSIONS: The reduced MMPs and increased TIMPs and ratios of undenatured to total soluble collagens and insoluble to total soluble collagens after LVAD support suggest that reduced MMP activity diminished damage to the matrix. These changes may contribute to the functional recovery and LV plasticity after LVAD support.

Overexpression of tumor necrosis factor- alpha activates both anti- and pro-apoptotic pathways in the myocardium.

We have previously reported that mice with cardiac-specific overexpression of tumor necrosis factor (TNF)- alpha develop myocardial inflammation, cardiac hypertrophy, and dilated cardiomyopathy. TNF- alpha is reported to induce apoptosis in cultured cardiac myocytes. To investigate the role of apoptosis in this transgenic model, wild-type controls (WT) and transgenic mice (TG) at the age of 1, 8, and 40 weeks were analyzed. Increased incidence of apoptosis in TG was indicated by DNA laddering. TUNEL assays revealed that the frequencies of apoptotic cells were increased in the TG myocardium at all ages. However, as revealed by histochemical and immunofluorescent methods, most of the apoptotic cells appeared to be non-myocytes even in the mice with overt congestive heart failure. To elucidate the signaling pathways responsible for TNF- alpha induced apoptosis, expression of apoptosis-related genes were evaluated by multi-probe RNase protection assays. Transcripts for death-domain-related proteins, including TNFR1, Fas, FADD, TRADD, and RIP, were constitutively expressed in WT and upregulated in the TG myocardium. Expression of caspase-1 through -8 was also enhanced in TG. While both anti- and pro-apoptotic Bcl-2 family genes were constitutively expressed in WT, TNF- alpha overexpression strongly induced anti-apoptotic A1 in the myocardium. Furthermore, TNF- alpha overexpression activated NF- kappa B, a mediator of anti-apoptotic pathways, in the myocardium. Thus, overexpression of TNF- alpha activated both anti- and pro-apoptotic pathways in the myocardium, resulting in an increase of apoptosis, primarily in non-myocytes. These results suggest that TNF- alpha by itself is not sufficient to induce apoptosis in cardiac myocytes in vivo.

UV light synergistically enhances the cardiotoxic effects of interleukin 1beta through peroxynitrite formation.

BACKGROUND: Proinflammatory cytokines play an important role in chronic cardiac diseases. METHODS AND RESULTS: Neonatal rat cardiomyocytes were exposed to interleukin (IL)-1beta (2 ng/mL) for 4 days. We assessed contractility through videomicroscopy and calcium transients with the Ca(2+)-sensitive dye fura-2. In IL-1beta-treated cells, the UV excitation (380 nm) necessary to induce dye fluorescence effected a rapid cessation of Ca(2+) transients and contraction, accompanied by calcium overload originating from an intracellular compartment. This occurred in the absence of fura-2 but required UV illumination. Incubation with 10 mmol/L N-acetylcysteine prevented this response, suggesting a free radical-mediated event. However, exposure to IL-1beta either increased or did not change the activity of the free radical scavengers superoxide dismutase, catalase, and glutathione peroxidase. In contrast, lipid peroxidation increased by 600% (P < or =.0001) in the IL-1beta plus UV-treated cells, an effect eliminated by L-NMMA. L-NMMA also completely abolished the UV-mediated cytotoxicity. We used immunohistochemistry to localize nitrotyrosine accumulation in the myocytes cotreated with IL-1beta and UV, an effect that was also blocked by L-NMMA. CONCLUSIONS: We hypothesize that the toxic radical peroxynitrite, arising from nitric oxide and superoxide anion, may be responsible for tetany and acute cardiomyocyte death. These results demonstrate the potential role of peroxynitrite in cardiotoxicity, which may be important in cardiac diseases associated with proinflammatory cytokines.

Demonstration of direct effects of growth hormone on neonatal cardiomyocytes.

The cellular and molecular basis of growth hormone (GH) actions on the heart remain poorly defined, and it is unclear whether GH effects on the myocardium are direct or mediated at least in part via insulin-like growth factor (IGF-1). Here, we demonstrate that the cultured neonatal cardiomyocyte is not an appropriate model to study the effects of GH because of artifactual loss of GH receptors (GHRs). To circumvent this problem, rat neonatal cardiomyocytes were infected with a recombinant adenovirus expressing the murine GHR. Functional integrity of GHR was suggested by GH-induced activation of the cognate JAK2/STAT5, MAPK, and Akt intracellular pathways in the cells expressing GHR. Although exposure to GH resulted in a significant increase in the size of the cardiomyocyte and increased expression of c-fos, myosin light chain 2, and skeletal alpha-actin mRNAs, there were no significant changes in IGF-1 or atrial natriuretic factor mRNA levels in response to GH stimulation. In this model, GH increased incorporation of leucine, uptake of palmitic acid, and abundance of fatty acid transport protein mRNA. In contrast, GH decreased uptake of 2-deoxy-d-glucose and levels of Glut1 protein. Thus, in isolated rat neonatal cardiomyocytes expressing GHR, GH induces hypertrophy and causes alterations in cellular metabolic profile in the absence of demonstrable changes in IGF-1 mRNA, suggesting that these effects may be independent of IGF-1.

Effects of soluble TNF receptor treatment on lipopolysaccharide-induced myocardial cytokine expression.

Tumor necrosis factor (TNF)-alpha plays a key role in the pathogenesis of septic shock syndrome, and myocardial TNF-alpha expression may contribute to this pathophysiology. We examined the myocardial expression of TNF-alpha-related cytokines and chemokines in mice exposed to lipopolysaccharide (LPS) and tested the effects of anti-TNF therapy on myocardial cytokine expression. Cytokine mRNA levels were measured by RNase protection assay, and protein levels in the plasma and myocardium were assessed by enzyme-linked immunosorbent assays. LPS (4 microg/g body wt ip) induced marked cytokine expression, including TNF-alpha, interleukin (IL)-1beta, IL-6, and monocyte chemotactic protein (MCP)-1, in both the plasma and myocardium. Pretreatment with adenovirus-mediated TNF receptor fusion protein (AdTNFR1; 10(9) plaque-forming units iv) decreased plasma cytokine levels. In contrast, whereas myocardial IL-1beta expression was also suppressed, expression of IL-6 and MCP-1 was not inhibited by AdTNFR1. In summary, anti-TNF treatment differentially altered the cytokine expression in the plasma and myocardium during endotoxemia. Inability to block myocardial expression of IL-6 and MCP-1 suggests a possible mechanism for the failure of anti-TNF therapies in the treatment of endotoxin shock.

Myocardial extracellular matrix remodeling in transgenic mice overexpressing tumor necrosis factor alpha can be modulated by anti-tumor necrosis factor alpha therapy.

Myocardial fibrosis caused by maladaptive extracellular matrix (ECM) remodeling is implicated in the dysfunction of the failing heart. Matrix metalloproteinases (MMPs) regulate ECM remodeling, and are regulated by cytokines. Transgenic mice with cardiac-specific overexpression of tumor necrosis factor alpha (TNF-alpha) (TNF1.6) develop heart failure. We hypothesized that modulation of TNF-alpha and/or MMP activity might alter the myocardial ECM remodeling process and the development of heart failure. To test this hypothesis, we took advantage of the TNF1.6 mice and studied soluble and total collagens and collagen type profiling by using hydroxyproline quantification, Sircol collagen assay, Northern blot analysis, and immunohistochemistry and studied myocardial function by using echocardiography. Progressive ventricular hypertrophy and dilation in the TNF1.6 mice were accompanied by a significant increase in MMP-2 and MMP-9 activity, an increase in collagen synthesis, deposition, and denaturation, and a decrease in undenatured collagens. In young TNF1.6 mice, these changes in the ECM were associated with marked diastolic dysfunction as demonstrated by significantly reduced transmitral Doppler echocardiographic E/A wave ratio. Anti-TNF-alpha treatment with adenoviral vector expressing soluble TNF-alpha receptor type I attenuated both MMP-2 and MMP-9 activity, prevented further collagen synthesis, deposition and denaturation, and preserved myocardial diastolic function in young, but not old, TNF1.6 mice. The results suggest a critical role of TNF-alpha and MMPs in myocardial matrix remodeling and functional regulation and support the hypothesis that both TNF-alpha and MMPs may serve as potential therapeutic targets in the treatment of heart failure.

Alterations in cardiac function and gene expression during autoimmune myocarditis in mice.

Although myocarditis has been implicated in the pathogenesis of heart failure, a definitive relationship between myocardial inflammation, cardiac dysfunction, and changes in myocyte gene expression has not been established. In this study, we examined the hypothesis that myocardial inflammation and replacement fibrosis following an autoimmune response can progress to cardiac dysfunction and may result in progression to the heart failure phenotype. SWXJ mice were immunized with cardiac myosin on day 0 and day 7, in order to induce an autoimmune response to the myosin protein. Cardiac catheterization via the right carotid artery was performed on days 14, 21, 28, 35, and 42, using a 1.4F Millar transducer-tipped catheter. Hearts were weighed, and cross-sections were cut and stained with either haematoxylin and eosin or Masson's trichrome, in order to identify areas of inflammation and/or fibrosis. Myocardial gene expression was determined by Northern blot analysis. In mice with histological evidence of myocarditis, the heart weight/body weight ratio increased beginning on day 14, and cardiac function decreased beginning on day 21. Myocardial inflammation was accompanied by significant fibrosis beginning on day 21. Quantitation of mRNA showed expression of ventricular atrial naturietic factor, as well as a decrease in myosin heavy chain alpha, beginning on day 21. These data demonstrate that autoimmune inflammation of the heart results in significant cardiac dysfunction, leading to phenotypic alterations similar to those demonstrated in human heart failure and animal models of heart failure.

Expression of proinflammatory cytokines in the failing human heart: comparison of recent-onset and end-stage congestive heart failure.

BACKGROUND: Plasma levels of proinflammatory cytokines, including tumor necrosis factor (TNF)-alpha and interleukin (IL)-6, are elevated in patients with congestive heart failure (CHF). Recent studies suggest that the failing human heart is a source of proinflammatory cytokines in the end-stage failing heart. However, the relevance of plasma levels to those of the myocardium remains undefined. We sought to compare cytokine expression in early and end-stage CHF, and to evaluate the correlation of tissue expression to plasma levels. METHODS: Two patient populations were studied: patients with recent-onset CHF, all with symptoms less than 6 months (n = 17, duration of symptoms 2.1 +/- 1.6 months, range of New York Heart Association (NYHA) 1 to 3), and end-stage heart-failure patients (n = 7) who underwent left-ventricular assist-device (LVAD) implantation (Duration of symptoms 47.1 +/- 28.0 months, all NYHA class 4). Plasma levels of TNF-alpha and IL-6 proteins were evaluated by an Enzyme-Linked Immuno-Sorbent Assay (ELISA), while myocardial levels of cytokine transcripts were assessed by ribonuclease (Rnase) protection assay. RESULTS: In patients with end-stage heart failure, TNF-alpha and IL-6 were increased in the plasma as well as in the myocardium (plasma: TNF-alpha = 7.7 +/- 2.3 pg/ml, IL-6 = 45.0 +/- 47.1 pg/ml; myocardium: TNF-alpha = 0.31 +/- 0.15% of glyceraldehyde 3-phosphate dehydrogenase (GAPDH) expression, IL-6 = 1.56 +/- 1.54% ). In contrast, despite elevated plasma levels of TNF-alpha and IL-6, the myocardium of patients with the recent onset of symptoms demonstrated minimal expression of TNF-alpha and IL-6 messenger ribonucleic acid (mRNA) (plasma: TNF-alpha = 4.3 +/- 1.7 pg/ml, IL-6 = 3.3 +/- 1.8 pg/ml; myocardium: TNF-alpha = 0.13 +/- 0. 04%, IL-6 = 0.02 +/- 0.04%). Plasma levels of TNF-alpha were significantly correlated with those in the myocardium when both populations were combined. (r = 0.69, p < 0.001). CONCLUSIONS: Cytokines are expressed in the myocardium in end-stage heart failure to a much greater degree than in patients with the recent-onset of symptoms. This suggests that induction of cytokines in the myocardium is a relatively late event in the pathogenesis of CHF. Furthermore, plasma levels of TNF-alpha correlates with mRNA expression in the myocardium and thus may serve as an appropriate marker of myocardial cytokine activation. Whether the production of cytokines in the failing human heart precedes the elevation of cytokines in the plasma remains undefined. Therefore, we studied expression of TNF-alpha and IL-6 in the myocardium as well as in the plasma in patients with early and end-stage CHF. The results have demonstrated that cytokines are expressed in the myocardium in end-stage heart failure to a much greater degree than in patients with the recent onset of symptoms. This suggests that induction of cytokines in the myocardium is a relatively late event in the pathogenesis of CHF.

The role of tumor necrosis factor alpha in the pathophysiology of congestive heart failure.

A variety of clinical and experimental investigations have suggested that tumor necrosis factor alpha (TNF-alpha) may play a role in the pathophysiology of heart failure. Serum levels of TNF-alpha are elevated in patients with heart failure, and both cardiac and infiltrating cells of the myocardium can produce this proinflammatory cytokine. Both cardiac myocytes and nonmyocytes also express receptors for TNF-alpha, and experimental studies on isolated cells, muscles, and transgenic models demonstrate the ability of TNF-alpha to recapitulate functional and biochemical alterations resembling that observed in human congestive heart failure. The intracellular pathways affected by TNF-alpha include production of ceramide and an alteration in calcium metabolism. Recent studies in both animal models and clinical investigations suggest that anti-TNF-alpha therapies may limit the pathophysiologic consequences of congestive heart failure.

Sex-related survival differences in murine cardiomyopathy are associated with differences in TNF-receptor expression.

Epidemiological evidence suggests that the prognosis of heart failure in women is better than in men. In our murine model of dilated cardiomyopathy arising from cardiac-specific overexpression of TNF-alpha, the 6-month survival rate was significantly better in females than in males. Young female transgenic mice exhibited left ventricular wall thickening without dilatation, whereas age-matched male transgenic hearts were markedly dilated. Basal and isoproterenol-stimulated fractional shortening was preserved in female transgenic mice, but not in male transgenic mice. Myocardial expression of proinflammatory cytokines and the extent of myocardial infiltrates were similar in male and female transgenic mice. Myocardial expression of TNF-receptor mRNAs (type I and type II) was significantly higher in male mice in both transgenic and wild-type littermates, whereas sex-specific differences were not observed in either peripheral white blood cells or liver tissue. After TNF-alpha challenge, myocardial but not liver production of ceramide was significantly higher in male than in female mice. Thus, differential expression of myocardial TNF receptors may contribute to sex differences in the severity of congestive heart failure and mortality consequent to cardiac-specific overexpression of TNF-alpha.

Soluble tumor necrosis factor receptor abrogates myocardial inflammation but not hypertrophy in cytokine-induced cardiomyopathy.

BACKGROUND: Transgenic mice with cardiac-specific overexpression of tumor necrosis factor (TNF)-alpha develop dilated cardiomyopathy. The present study was designed to evaluate therapeutic effects of adenovirus-mediated neutralization of TNF-alpha on this model. METHODS AND RESULTS: An adenovirus encoding the 55-kDa TNF receptor-IgG fusion protein (AdTNFRI) was injected intravenously into 6-week-old transgenic mice, which resulted in high levels of TNFRI in both plasma and myocardium. AdTNFRI did not reverse cardiomegaly but abrogated myocardial inflammation. Furthermore, AdTNFRI blocked the myocardial expression of intercellular adhesion molecule-1 and downstream cytokines, including interleukin-1beta and monocyte chemotactic protein-1. Downregulation of alpha-myosin heavy chain was restored by the treatment, whereas upregulation of beta-myosin heavy chain was not reversed. In contrast, the downregulation of sarcoplasmic reticulum Ca(2+)-ATPase and phospholamban was normalized by AdTNFRI. Echocardiographic measurements showed that left ventricular end-systolic diameter was significantly larger in transgenic mice than in control mice, and this increase was reversed by the AdTNFRI treatment. However, left ventricular wall thickening was not reversed. CONCLUSIONS: These results suggest that anti-TNF therapy may hold promise in the treatment of end-stage heart failure.

Interplay of matrix metalloproteinases, tissue inhibitors of metalloproteinases and their regulators in cardiac matrix remodeling.

Myocardial fibrosis due to maladaptive extracellular matrix remodeling contributes to dysfunction of the failing heart. Further elucidation of the mechanism by which myocardial fibrosis and dilatation can be prevented or even reversed remains of great interest as a potential means to limit myocardial remodeling and dysfunction. Matrix metalloproteinases (MMPs) are the driving force behind extracellular matrix degradation during remodeling and are increased in the failing human heart. MMPs are regulated by a variety of growth factors, cytokines, and matrix fragments such as matrikines. In the present report, we discuss the regulation of MMPs, the role of MMPs in the development of cardiac fibrosis, and the modulation of MMP activity using gene transfer and knockout technologies. We also present recent findings from our laboratory on the regulation of the extracellular MMP inducer (EMMPRIN), MMPs, and transforming growth factor-beta(1) in the failing human heart before and after left ventricular assist device support, as well as the possibility of preventing ventricular fibrosis using different anti-MMP strategies. Several studies suggest that such modulation of MMP activity can alter ventricular remodeling, myocardial dysfunction, and the progression of heart failure. It is therefore suggested that the interplay of MMPs and their regulators is important in the development of the heart failure phenotype, and myocardial fibrosis in heart failure may be modified by modulating MMP activity.

The role of tumor necrosis factor in the pathophysiology of heart failure.

Recent studies have focused their attention on the role of the proinflammatory cytokine tumor necrosis factor (TNF) in the development of heart failure. First recognized as an endotoxin-induced serum factor that caused necrosis of tumors and cachexia, it is now recognized that TNF participates in the pathophysiology of a group of inflammatory diseases including rheumatoid arthritis and Crohn's disease. The normal heart does not express TNF; however, the failing heart produces robust quantities. Furthermore, there is a direct relationship between the level of TNF expression and the severity of disease. In addition, both in vivo and in vitro studies demonstrate that TNF effects cellular and biochemical changes that mirror those seen in patients with congestive heart failure. Furthermore, in animal models, the development of the heart failure phenotype can be abrogated at least in part by anticytokine therapy. Based on information from experimental studies, investigators are now evaluating the clinical efficacy of novel anticytokine and anti-TNF strategies in patients with heart failure; one such strategy is the use of a recombinantly produced chimeric TNF alpha soluble receptor. Thus, in view of the emerging importance of proinflammatory cytokines in the pathogenesis of heart disease, we review the biology of TNF, its role in inflammatory diseases, the effects of TNF on the physiology of the heart and the development of clinical strategies that target the cytokine pathways.

Proinflammatory cytokines regulate tissue inhibitors of metalloproteinases and disintegrin metalloproteinase in cardiac cells.

OBJECTIVE: Tissue inhibitors of metalloproteinases (TIMPs) are downregulated in the failing human heart. The objective of the present study was to test the hypothesis that cytokines might be involved in the regulation of TIMPs in cardiac cells. METHODS: Neonatal Sprague-Dawley rat ventricular cells were exposed to 100 units/ml tumor necrosis factor-alpha and/or 5 ng/ml interleukin-1 beta. The mRNA and protein expression of TIMPs-1-4 and disintegrin metalloproteinase was analyzed using Northern blot, ELISA and/or Western blot, respectively. Proteolytic activity and extracellular matrix degradation and turnover were determined using gelatin zymography and pulse-chase experiments. RESULTS: The TIMP-1 mRNA was upregulated in cardiac cells, while TIMP-1 protein levels were unchanged in myocytes but downregulated in non-myocytes. The TIMP-2 expression did not change with the cytokine treatment. TIMP-3 was downregulated at both the mRNA and protein levels in cardiac cells. TIMP-4 protein was transiently increased and then returned to control level. In contrast, disintegrin metalloproteinase mRNA and protein were significantly upregulated in those cells. The gelatinolytic activity and extracellular matrix protein degradation were significantly increased. CONCLUSIONS: Tumor necrosis factor-alpha and interleukin-1 beta regulate the expression of TIMPs and disintegrin metalloproteinase, which may in turn contribute to the increased matrix degradation in cardiac cells. Since heart failure in humans is characterized by both re-expression of myocardial cytokines and remodeling of the extracellular matrix, those in vitro results suggest a potential role for those cytokines in the regulation of extracellular matrix remodeling and therefore in the transition to the end-stage heart failure phenotype.

Strümpell's disease in a patient presenting for Cesarean section.

PURPOSE: The anesthetic management of a parturient with Strumpell's disease (hereditary or familial spastic paraparesis) who presented for Cesarean section is described. This neurological disorder is briefly reviewed and anesthetic implications of the condition are discussed. CLINICAL FEATURES: A 30-yr-old woman in premature labour presented for Cesarean section. She had bilateral lower limb spastic paresis which had resulted in her being confined to a wheelchair from the age of 13 yr. A diagnosis of Strumpell's disease had been made in childhood. She was currently receiving thromboprophylaxis, having suffered a deep venous thrombosis four weeks after a previous Cesarean section. The patient was in mild respiratory distress. Despite a history of uneventful general anesthesia and the aforementioned complicating factors, epidural anesthesia was considered the most appropriate technique in these circumstances. An epidural catheter was sited at the L3-L4 interspace. Adequate anesthesia for the procedure was obtained after administration of 20 ml lidocaine 2% with 100 microg epinephrine and 100 microg fentanyl in saline. Postoperatively and at six month follow-up there were no neurological complications related to the use of epidural anesthesia. CONCLUSION: Strumpell's disease is an inherited progressive spastic paresis predominantly affecting the lower extremities. Epidural anesthesia appears to be an appropriate technique when administering anesthesia for Cesarean section under similar circumstances.