[Anesthesiological implications of minimally invasive valve interventions : Transcatheter aortic valve implantation, clip reconstruction on the mitral and tricuspid valve]. / Anästhesiologische Implikationen bei minimal-invasiven Klappeninterventionen : "Transkatheter aortic valve implantation", MitraClip und Trikuspidalklappe.

Catheter-guided interventional implantation of cardiac valves is one of the main developments in cardiology over the past 15 years. It is characterized by a close interdisciplinary cooperation in the heart team (H-team), which consists of cardiac anesthesiologists, cardiologists and heart surgeons. This co-responsibility for anesthesia, which is demanded by the legislator (Federal Joint Committee, G­BA, July 2015), includes not only qualified training for the cardiac anesthesiologist, including transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE) but also several years of experience in cardiac anesthesia and correlates with the recommendations of the German Society for Anaesthesiology and Intensive Care Medicine. In accompaniment with the demographic development, the number of heart valve diseases increases with age. More than 50% of all heart operations are performed on patients over the age of 70 years and nearly 20% on patients over the age of 80 years. Minimally invasive procedures are outstanding opportunities for patients who were initially classified as inoperable. Therefore, anesthesiologists must have precise knowledge of the possible complications related to the procedure itself. Additionally, it challenges the anesthesiologist with unconventional situations in the care of older patients who are exposed to a higher risk. The aforementioned risks are organic functional restrictions, increasing number of comorbidities and more severe exposure due to malnutrition and frailty; however, monitoring methods are also being developed aiming for patient-specific anesthesia management and analgesia treatment. This article discusses the interventional procedures of heart valvular diseases as well as the hemodynamic changes associated with the procedures from the anesthesiologist's point of view. To present examples, we have selected transcatheter aortic valve replacement (TAVR) and the interventional procedure of mitral and tricuspid valve insufficiency called MitraClip and TricaClip. A thorough examination of the procedural risk rate shows that despite minimizing the surgical intervention by miniaturizing the devices, the presence of an experienced cardiac anesthesiologist is obligatory.

Alternatively spliced tissue factor and full-length tissue factor protect cardiomyocytes against TNF-α-induced apoptosis.

Tissue Factor (TF) is expressed in various cell types of the heart, such as cardiomyocytes. In addition to its role in the initiation of blood coagulation, the TF:FVIIa complex protects cells from apoptosis. There are two isoforms of Tissue Factor (TF): "full length" (fl)TF--an integral membrane protein, and alternatively spliced (as)TF--a protein that lacks a transmembrane domain and can thus be secreted in a soluble form. Whether asTF or flTF affects apoptosis of cardiomyocytes is unknown. In this study, we examined whether asTF or flTF protects murine cardiomyocytes from TNF-α-induced apoptosis. We used murine cardiomyocytic HL-1 cells and primary murine embryonic cardiomyocytes that overexpressed either murine asTF or murine flTF, and stimulated them with TNF-α to initiate cell death. Apoptosis was assessed by annexin-V assay, propidium iodide assay, as well as activation of caspase-3 and -9. In addition, signaling via integrins, Akt, NFκB and Erk1/2, and gene-expression of Bcl-2 family members were analyzed. We here report that overexpression of asTF reduced phosphatidylserine exposure upon TNF-α-stimulation. asTF overexpression led to an increased expression and phosphorylation of Akt, as well as up-regulation of the anti-apoptotic protein Bcl-x(L). The anti-apoptotic effects of asTF overexpression were mediated via α(V)ß(3)/Akt/NFκB signaling and were dependent on Bcl-x(L) expression in HL-1 cells. The anti-apoptotic activity of asTF was also observed using primary cardiomyocytes. Analogous yet less pronounced anti-apoptotic sequelae were observed due to overexpression of flTF. Importantly, cardiomyocytes deficient in TF exhibited increased apoptosis compared to wild type cells. We propose that asTF and flTF protect cardiomyocytes against TNF-α-induced apoptosis via activation of specific signaling pathways, and up-regulation of anti-apoptotic members of the Bcl-2 protein family.

Long-term clopidogrel administration following severe coronary injury reduces proliferation and inflammation via inhibition of nuclear factor-kappaB and activator protein 1 activation in pigs.

BACKGROUND: The optimal duration of clopidogrel treatment following percutaneous coronary intervention (PCI) and the patient population that would benefit most are still unknown. In a porcine coronary injury model, we tested two different durations of clopidogrel treatment on severely or moderately injured arteries and examined the arterial response to injury. To understand the molecular mechanism, we also investigated the effects on transcription factors nuclear factor-kappaB (NF-kappaB) and activator protein 1 (AP-1). MATERIALS AND METHODS: In 24 cross-bred pigs, one coronary artery was only moderately injured by percutaneous transluminal coronary angioplasty (PTCA) and one coronary artery was severely injured by PTCA and subsequent beta-irradiation (Brachy group). Animals received 325 mg aspirin daily for 3 months and 75 mg clopidogrel daily for either 28 days [short-term (ST) clopidogrel group] or 3 months [long-term (LT) clopidogrel group]. RESULTS: After 3 months, the number of proliferating cells per cross-section differed significantly between ST and LT in both injury groups (PTCA(ST) 90.2 +/- 10.3 vs. PTCA(LT )19.2 +/- 4.7, P < 0.05; Brachy(ST) 35.8 +/- 8.4 vs. Brachy(LT) 7.5 +/- 2.0, P < 0.05). Similar results were seen for inflammatory cells (CD3(+) cells): PTCA(ST) 23.5 +/- 3.55 vs. PTCA(LT )4.67 +/- 0.92, P < 0.05; Brachy(ST) 83.17 +/- 11.17 vs. Brachy(LT) 20 +/- 4.82, P < 0.05). Long-term administration also reduced the activity of NF-kappaB and AP-1 by 62-64% and 42-58%, respectively. However, the effects of different durations of clopidogrel administration on artery dimensions were not statistically significant. CONCLUSIONS: Regarding inflammation and transcription factor activity at the PCI site, long-term clopidogrel administration is superior to short-term administration, especially in severely injured arteries. Transferring our results to the human situation, patients with more severely diseased arteries may benefit from a prolonged clopidogrel medication after PCI.

Mouse ten-m/Odz is a new family of dimeric type II transmembrane proteins expressed in many tissues.

The Drosophila gene ten-m/odz is the only pair rule gene identified to date which is not a transcription factor. In an attempt to analyze the structure and the function of ten-m/odz in mouse, we isolated four murine ten-m cDNAs which code for proteins of 2,700-2, 800 amino acids. All four proteins (Ten-m1-4) lack signal peptides at the NH2 terminus, but contain a short hydrophobic domain characteristic of transmembrane proteins, 300-400 amino acids after the NH2 terminus. About 200 amino acids COOH-terminal to this hydrophobic region are eight consecutive EGF-like domains. Cell transfection, biochemical, and electronmicroscopic studies suggest that Ten-m1 is a dimeric type II transmembrane protein. Expression of fusion proteins composed of the NH2-terminal and hydrophobic domain of ten-m1 attached to the alkaline phosphatase reporter gene resulted in membrane-associated staining of the alkaline phosphatase. Electronmicroscopic and electrophoretic analysis of a secreted form of the extracellular domain of Ten-m1 showed that Ten-m1 is a disulfide-linked dimer and that the dimerization is mediated by EGF-like modules 2 and 5 which contain an odd number of cysteines. Northern blot and immunohistochemical analyses revealed widespread expression of mouse ten-m genes, with most prominent expression in brain. All four ten-m genes can be expressed in variously spliced mRNA isoforms. The extracellular domain of Ten-m1 fused to an alkaline phosphatase reporter bound to specific regions in many tissues which were partially overlapping with the Ten-m1 immunostaining. Far Western assays and electronmicroscopy demonstrated that Ten-m1 can bind to itself.

Genomic expression profiling of human inflammatory cardiomyopathy (DCMi) suggests novel therapeutic targets.

The clinical phenotype of human dilated cardiomyopathy (DCM) encompasses a broad spectrum of etiologically distinct disorders. As targeting of etiology-related pathogenic pathways may be more efficient than current standard heart failure treatment, we obtained the genomic expression profile of a DCM subtype characterized by cardiac inflammation to identify possible new therapeutic targets in humans. In this inflammatory cardiomyopathy (DCMi), a distinctive cardiac expression pattern not described in any previous study of cardiac disorders was observed. Two significantly altered gene networks of particular interest and possible interdependence centered around the cysteine-rich angiogenic inducer 61 (CYR61) and adiponectin (APN) gene. CYR61 overexpression, as in human DCMi hearts in situ, was similarly induced by inflammatory cytokines in vascular endothelial cells in vitro. APN was strongly downregulated in DCMi hearts and completely abolished cytokine-dependent CYR61 induction in vitro. Dysbalance between the CYR61 and APN networks may play a pathogenic role in DCMi and contain novel therapeutic targets. Multiple immune cell-associated genes were also deregulated (e.g., chemokine ligand 14, interleukin-17D, nuclear factors of activated T cells). In contrast to previous investigations in patients with advanced or end-stage DCM where etiology-related pathomechanisms are overwhelmed by unspecific processes, the deregulations detected in this study occurred at a far less severe and most probably fully reversible disease stage.

Neurocan is dispensable for brain development.

Neurocan is a component of the extracellular matrix in brain. Due to its inhibition of neuronal adhesion and outgrowth in vitro and its expression pattern in vivo it was suggested to play an important role in axon guidance and neurite growth. To study the role of neurocan in brain development we generated neurocan-deficient mice by targeted disruption of the neurocan gene. These mice are viable and fertile and have no obvious deficits in reproduction and general performance. Brain anatomy, morphology, and ultrastructure are similar to those of wild-type mice. Perineuronal nets surrounding neurons appear largely normal. Mild deficits in synaptic plasticity may exist, as maintenance of late-phase hippocampal long-term potentiation is reduced. These data indicate that neurocan has either a redundant or a more subtle function in the development of the brain.

Entorhinal cortex lesion in adult rats induces the expression of the neuronal chondroitin sulfate proteoglycan neurocan in reactive astrocytes.

The chondroitin sulfate proteoglycan neurocan is a major component of brain extracellular matrix during development. Neurocan is primarily synthesized by neurons and has the ability to interact with cell adhesion molecules involved in the regulation of cell migration and axonal growth. Within the first weeks postnatally, neurocan expression is strongly downregulated. To test whether neurocan is reexpressed in areas of axonal growth (sprouting) after brain injury, the time course of neurocan expression was analyzed in the denervated fascia dentata of the rat after entorhinal cortex lesion (12 hr; 1, 2, 4, and 10 d; 2 and 4 weeks; and 6 months after lesion). In the denervated zone, immunohistochemistry revealed neurocan-positive astrocytes by 2 d after lesion and a diffuse labeling of the extracellular matrix at all later time points. Electron microscopy confirmed the deposition of neurocan in the extracellular matrix compartment. In situ hybridization demonstrated a strong upregulation of neurocan mRNA within the denervated outer molecular layer 1 and 4 d after lesion. The combination of in situ hybridization with immunohistochemistry for glial fibrillary acidic protein demonstrated that the neurocan mRNA-expressing cells are astrocytes. These data demonstrate that neurocan is reexpressed in the injured brain. In contrast to the situation during development, astrocytes, but not neurons, express neurocan and enrich the extracellular matrix with this molecule. Similar to the situation during development, neurocan is expressed in an area of active axon growth, and it is suggested that neurocan acts to maintain the boundaries of the denervated fascia dentata after entorhinal cortex lesion.

Testing platelet activation with a shear-dependent platelet function test versus aggregation-based tests: relevance for monitoring long-term glycoprotein IIb/IIIa inhibition.

BACKGROUND: Tests developed to monitor glycoprotein (GP) IIb/IIIa blockade do not properly reflect platelet function in vivo and need a baseline (pretreatment) value. Because GP IIb/IIIa is essential in platelet aggregation and thrombosis under shear conditions, a flow-dependent approach to monitor its inhibition can be used. METHODS AND RESULTS: We compared a test based on flow-dependent platelet deposition, the Cone and Platelet Analyzer (CPA), with in vitro platelet aggregometry and the Rapid Platelet Function Assay (RPFA) on platelet function after GP IIb/IIIa inhibition. In vitro, increasing concentrations of abciximab (0% to 100% receptor occupancy) were tested. Ex vivo, platelet function was monitored with the CPA and with aggregometry for up to 1 week after abciximab administration. The CPA was better correlated with the percentage of free GP IIb/IIIa receptors than was aggregometry or the RPFA. Only the RPFA, when expressed as a ratio over baseline (pretreatment), was comparable to the CPA. Ex vivo, the CPA, but not aggregometry, showed prolonged platelet inhibition with gradual recovery from GP IIb/IIIa receptor blockade in the first week after abciximab administration. CONCLUSIONS: Platelet function assessment by shear-induced deposition is a reliable test to monitor a wide range of GP IIb/IIIa inhibition. Its accuracy does not require a baseline reference. The effects of GP IIb/IIIa blockade on platelet function should be examined under high shear conditions.

Blood thrombogenicity in type 2 diabetes mellitus patients is associated with glycemic control.

OBJECTIVES: This study was designed to determine whether blood thrombogenicity is related to chronic glycemic control in type 2 diabetes mellitus (T2DM). BACKGROUND: Type 2 diabetes mellitus is associated with accelerated atherosclerosis and a high rate of arterial thrombotic complications. Whether increased blood thrombogenicity is associated with glycemic control has not been properly tested. METHODS: Forty patients with T2DM with hemoglobin A1c (HbA1c) > or =7.5% were selected. Maintaining their current hypoglycemic therapies, patients were randomized into a conservative (diet modification plus placebo) or intensive (diet modification plus troglitazone) hypoglycemic regimen for three months. Blood thrombogenicity was measured at baseline and after three months with the Badimon ex vivo perfusion chamber and assessed as platelet-thrombus formation. The repeated measurements allowed every patient to be his/her own control. RESULTS: Patients in both groups (48% and 74% of the conservative and intensive groups, respectively) improved glucose control (HbA1c reduction > or =0.5%), showing a significant decrease in blood thrombogenicity. A significant positive correlation was observed between the reduction in thrombus formation and the reduction in HbA1c (r = 0.47, p < 0.01). The reduction in HbA1c achieved by both treatments was comparable. Patients without glycemic improvement showed no change in blood thrombogenicity. Improved glycemic control was the only significant predictor of a decrease in blood thrombogenicity. CONCLUSIONS: In T2DM, there is an association between improved glycemic control and blood thrombogenicity reduction. The effect of glycemic control on the thrombotic complications of T2DM patients deserves further investigation.

Tissue factor, the blood, and the arterial wall.

Thrombogenic tissue factor (TF) on cell-derived microparticles is present in the circulating blood of patients with acute coronary syndromes. Recently, we reported that leukocytes transfer TF-positive particles to platelet thrombi, making them capable of triggering and propagating thrombus growth. This observation changes the original dogma that vessel-wall injury and exposure of tissue factor within the vasculature to blood is sufficient for the occurrence of arterial thrombosis. The transfer of TF-positive leukocyte particles is dependent on the interaction of CD15 and TF with platelet thrombi. The inhibition of TF transfer and TF activity suggests a novel therapeutic approach to the prevention of thrombosis that may prove to be effective in disorders associated with increased blood TF.

Tissue-specific transcription pattern of the adenine nucleotide translocase isoforms in humans.

Three adenine nucleotide translocase isoforms (ANT1, ANT2 and ANT3) are coded by different genes. The relative amounts of the three ANT isoform mRNAs were determined in detail in various human tissues. ANT isoforms were co-expressed in all tested tissues revealing tissue-specific transcription patterns. The highest ANT1 mRNA proportions were found in terminally differentiated tissues like skeletal muscle, heart and brain, whereas ANT2 was mainly expressed in tissues capable of proliferation and regeneration as in the kidneys, spleen, liver, fibroblasts and lymphocytes. The ANT3 mRNA proportion was not prominently expressed in any of the tissues tested. In conclusion, tissue-specific expression of ANT isoforms is strongly related to the state of cellular differentiation.

Dynamic spatiotemporal expression patterns of neurocan and phosphacan indicate diverse roles in the developing and adult mouse olfactory system.

The chondroitin sulfate proteoglycans neurocan and phosphacan are believed to modulate neurite outgrowth by binding to cell adhesion molecules, tenascin, and the differentiation factors heparin-binding growth-associated molecule and amphoterin. To assess the role of these chondroitin sulfate proteoglycans in the olfactory system, we describe here their expression patterns during both embryonic and postnatal development in the mouse. Immunoreactivity for neurocan was first detected in primary olfactory neurons at embryonic day 11. 5 (E11.5). Neurocan was expressed by primary olfactory axons as they extended toward the rostral pole of the telencephalon as well as by their arbors in glomeruli after they contacted the olfactory bulb. The role of neurocan was examined by growing olfactory neurons on an extracellular matrix substrate containing neurocan or on extracellular matrix in the presence of soluble neurocan. In both cases, neurocan strongly promoted neurite outgrowth. These results suggest that neurocan supports the growth of primary olfactory axons through the extracellular matrix as they project to the olfactory bulb during development. Phosphacan, unlike neurocan, was present within the mesenchyme surrounding the E11.5 and E12.5 nasal cavity. This expression decreased at E13.5, concomitant with a transient appearance of phosphacan in nerve fascicles. Within the embryonic olfactory bulb, phosphacan was localised to the external and internal plexiform layers. However, during early postnatal development phosphacan was concentrated in the glomerular layer. These results suggest that phosphacan may play a role in delineating the pathway of growing olfactory axons as well as defining the laminar organization of the bulb. Together, the spatiotemporal expression patterns of neurocan and phosphacan indicate that these chondroitin sulfate proteoglycans have diverse in situ roles, which are dependent on context-specific interactions with extracellular and cell adhesion molecules within the developing olfactory nerve pathway.

Statins and cardiovascular diseases: the multiple effects of lipid-lowering therapy by statins.

Cholesterol lowering involving different therapies improves the clinical outcome of patients. To define the underlying pathomechanism, we studied whether treatment with statins was associated with changes in blood thrombogenicity, endothelial dysfunction and soluble adhesion molecule levels. Fifty hypercholesterolemic patients were treated with pravastatin (40 mg/day, n=24) or simvastatin (20 mg/day, n=26). Lipid profile and blood thrombogenicity were assessed in all patients before and after 3 months of cholesterol reducing therapy. Blood thrombogenicity was assessed as thrombus formation, perfusing non-anticoagulated blood directly from the patients' vein through the Badimon perfusion chamber (shear rate 1690/s). Endothelial-dependent vasomotor response was tested by laser-Doppler flowmeter. Soluble adhesion molecule level were measured by ELISA. Total and LDL cholesterol were reduced in the two treatment groups by statin therapy. Statin therapy was associated with a significant reduction in blood thrombogenicity and endothelium-dependent vasoresponse. No differences were observed between simvastatin or pravastatin treatment. Lipid lowering by statins had no effect on plasma levels of fibrinogen, sL-selectin, sP-selectin and sICAM-1 antigen. Cholesterol lowering by both statins reduced the increased blood reactivity and endothelial dysfunction present under hypercholesterolemia. The multiple effects of lipid lowering therapy by statins may explain the benefits observed in recent epidemiological trials.

Comparative study of antithrombotic effect of a low molecular weight heparin and unfractionated heparin in an ex vivo model of deep arterial injury.

Thrombosis after plaque rupture triggers the onset of acute coronary events. The treatment of choice for patients with acute coronary syndromes is conventional unfractionated heparin. Low molecular weight heparin has recently been reported to be as effective and even safer than unfractionated heparin. In this study, the effects of the low molecular weight heparin reviparin and unfractionated heparin on thrombus formation were examined under dynamic conditions using an extracorporeal perfusion chamber in a porcine model. Thrombus formation was assessed by the deposition of porcine 123I-fibrin(ogen) and autologous 111In-platelets on porcine tunica media at high and low shear rates. Reviparin reduced the fibrinogen molecules deposited on injured vessels at high shear rates (252+/-80 molecules x 10(12)/cm2 for reviparine (200 U/kg/hour) vs. 624+/-70 x 10(12)/cm for unfractionated heparin (200 U/kg/hour) (p<0.05). At low shear rates, fibrinogen deposition was also significantly reduced by reviparin (130+/-15 molecules x 10(12)/cm2) compared to unfractionated heparin (192+/-40 x 10(12)/cm2 at 200 U/kg/hour; p<0.05). No change in platelet deposition was detected after heparin administration in either treatment group. In conclusion, the low molecular weight heparin reviparin has a higher antithrombotic potential than unfractionated heparin. Reviparin may have advantages over unfractionated heparin in treatment and prevention of acute coronary syndromes.

Continuous hormone replacement therapy with estradiol valerate and chlormadinone acetate in adjustable dosages. A preliminary study.

A group of 62 peri- and postmenopausal women suffering from vasomotor disturbances and a variety of other symptoms were treated with estradiol valerate and chlormadinone acetate continuously using an adjustable dosage regimen. They obtained complete relief from vasomotor symptoms. The continuation rate was 81% after 1 year. In 18 patients the dose had to be adjusted because of breakthrough bleeding (n = 12), mastodynia (n = 3), and for the prevention of bone loss. In 11/12 patients breakthrough bleeding could be stopped by adjusting the dosage. This regimen seems to offer a more flexible approach to hormone replacement therapy (HRT) in the postmenopause than presently available combined preparations for continuous use.

The extracellular matrix and its role in cell migration and development of the enteric nervous system.

The extracellular matrix (ECM), a network consisting of many different macromolecules, fulfils many important functions in every multicellular organism, especially during their development. Among other factors, ECM molecules are necessary for cell migration and also regulate cell differentiation, as could be shown in a wide range of animals. The enteric nervous system (ENS) is built up by neural crest cells (NCC) migrating along predetermined pathways into the developing gut. Studies done for example in mice and chickens did not only enable scientists to reconstruct these routes but also to demonstrate their dependence on ECM molecules such as laminin. Currently we are investigating the influence of different ECM constituents, growth factors and noxious factors on NCC migration and differentiation in the developing chicken gut. The easy handling of the chicken embryo and the use of different methods will give us valuable insights for further investigations.

How to approach the ENS: various ways to analyse motility disorders in situ and in vitro.

Motility disorders of the human intestine are so variable that they cannot be diagnosed by just one technique. Their aetiology is obviously so varied that they have to be approached with a broad range of technical methods. These reach from the simple haematoxylin-stained section to the isolation of stem or precursor cells. In this study, various methods to investigate the enteric nervous system and its surrounding tissue are demonstrated. While sections from paraffin-embedded material or cryostat sections provide only a two-dimensional perspective of the ENS, the whole-mount method yields three-dimensional perspectives of large areas of the gut wall. The three-dimensional impression can even be enhanced by electron microscopy of the isolated ENS. Dynamical aspects of ENS development can be tackled by in vitro studies. The myenteric plexus can be isolated and cultivated under the influence of the microenvironment (protein extracts). Although the postnatal myenteric plexus is not fully developed, the choice of embryological neuronal cells seems to be more effective for certain approaches. They can be isolated from the embryonic mouse gut and cultivated under the influence of various factors. This method seems to us a valuable tool for the investigation of the aetiology of motility disorders, although only a "complete" approach which considers all available methods will yield at the end a clear understanding which might lead to new therapeutical concepts.

The microenvironment in chronic pancreatitis and pancreatic cancer induces neuronal plasticity.

BACKGROUND: Pancreatic neuropathy in chronic pancreatitis (CP) and pancreatic cancer (PCa) is characterized by pancreatic neuropathy, i.e. increased neural density and hypertrophy, which are associated with neuropathic pain. To better understand the mechanism of these neuropathic alterations, we aimed at achieving an in-vitro simulation of the intrapancreatic neuroplasticity. METHODS: Dissociated myenteric plexus (MP) and dorsal root ganglia (DRG) neurons of newborn rats were treated with normal human pancreas (NP), CP or PCa tissue extracts. Furthermore, MP and DRG neurons were cultured in supernatants from different pancreatic cancer cell lines (PCC) and human pancreatic stellate cells (hPSC) obtained from either CP or PCa tissues. For analysis, the neurite density, outgrowth, neuronal branching capacity and perikaryonal size were quantified. KEY RESULTS: Myenteric plexus and DRG neurons grown in CP and PCa tissue extracts built denser networks than in NP extracts. Both neuronal types showed a strong neurite outgrowth, more complex branching pattern and a somatic hypertrophy in CP and PCa extracts. Pancreatic cancer cell supernatants induced a prominent neurite outgrowth, increased neurite density and perikaryonal hypertrophy in MP and DRG neurons. Supernatants of CP-derived hPSC strongly stimulated neurite outgrowth. Glial density in MP cultures was strikingly increased by PCa tissue extracts. CONCLUSIONS & INFERENCES: Intrapancreatic microenvironment in CP and PCa induces neuroplastic alterations under in-vitro conditions, leading to increased neural density and hypertrophy. Thus, due to its neurotrophic attributes, the intrapancreatic microenviroment in CP and PCa seems to be a key player in the generation of pancreatic neuropathy and neuroplasticity.

Regulation of cardiomyocyte full-length tissue factor expression and microparticle release under inflammatory conditions in vitro.

SUMMARY BACKGROUND: Myocardial inflammation is associated with an increase in circulating microparticles (MPs) and procoagulability. OBJECTIVES: We determined whether acute inflammation was associated with altered full-length tissue factor (flTF) expression and increased procoagulability in cardiomyocytic cells. METHODS: This study examined the transcriptional regulation of flTF expression in murine cardiomyocytic (HL-1) cells. Also, the generation of MPs by HL-1 cells and their ability to diffuse through an artificial endothelium was evaluated. RESULTS: Constitutive and tumor necrosis factor-alpha (TNF-alpha)-induced flTF expression of HL-1 was reduced when c-Jun N-terminal kinase (JNK) was inhibited. Tissue factor (TF)-positive procoagulant MPs were released from HL-1 cells in response to TNF-alpha. JNK inhibition potentiated the release of MPs from HL-1 cells without affecting MP-associated TF activity. MP generation was dependent on RhoA activation and associated with a reorganization of the actin cytoskeleton. Increased diffusion of HL-1-derived MPs through an endothelial monolayer was found after TNF-alpha treatment. The increased diffusion was dependent not only on TNF-alpha but also on HL-1-released mediators. CONCLUSIONS: Full-length TF expression in HL-1 cells was regulated through JNK. The TNF-alpha-induced increase in procoagulability was mediated through RhoA-dependent release of flTF-bearing MPs. These MPs were able to diffuse through an endothelial barrier adjacent to HL-1 cells and increased the procoagulability of the extracellular endothelial space. Cardiomyocytes seem to be a likely source of flTF-bearing procoagulant MPs.