Q-switched Nd:YAG laser protects human keratinocytes from oxidative stress and inflammation via AhR-Nrf2 pathway.

In recent years, some treatments for esthetic and pathologic skin conditions have increasingly been based on the use of non-ablative neodymium-doped yttrium aluminum garnet (Nd:YAG) laser due to its greater penetration ability than other types of lasers, few contraindications, minimal side effects, no damage for epidermidis and the rapid recovery of the treated patients. The skin is frequently exposed to many stressors such as radiation, toxic substances, metabolites, foods, mechanical insults, and allergen exposition that cause oxidative damage and have a decisive influence on the aging process. The imbalance between reactive oxygen species, reactive nitrogen species, and the malfunctioning of the antioxidant defense system promotes the establishment of an excessive inflammatory process, which can induce various diseases including cancer and neurodegenerative disorders. The present study investigated the cytoprotective function of Q-switched Nd:YAG laser against stress aging and cell injury in HaCaT cells. We evaluated the effect of the laser on antioxidant defenses, inflammation, metalloproteinases' expression, and the AhR-Nrf2 pathway. Q-switched Nd:YAG is able to upregulate the AhR pathway and the expression of IL-6 and TGF-ß, which are involved in wound repair process, and to downregulate the expression of MMP-2 and 9, so preventing the collagen degradation. Q-switched Nd:YAG can stimulate the cellular antioxidant defenses by activating the AhR-Nrf2 system.

Hyaluronic acid-based fillers in patients with autoimmune inflammatory diseases.

The use of hyaluronic acid (HA)-based aesthetic therapies is growing steadily, and according to the International Society of Aesthetic Plastic Surgery, more than 4.3 million aesthetic procedures using HA were performed in 2019, an increase of 15.7% than 2018. More people are offering these types of services, often without proper training or qualifications. Therefore, there is an increasing number of reports in the literature relating to possible adverse events, with subsequent therapeutic problems and more or less serious consequences for patients. The aim of this research is to carry out a review of the literature in order to evaluate the impact of hyaluronic acid-based fillers in patients with autoimmune inflammatory diseases, in particular scleroderma and Systemic Lupus Erythematosus (SLE). Although HA plays a central role in the inflammatory process, the use of HA-based fillers in patients with autoimmune inflammatory diseases is still controversial. HA, in fact, in inflamed tissues helps to propagate the inflammatory response and, injected in the form of a dermal filler, could potentially promote reactivation of the underlying disease. For this reason, many specialists do not perform HA-based aesthetic treatments in patients with scleroderma or SLE. However, recent scientific evidence suggests that the use of HA-based fillers in patients with scleroderma can lead to improvement of skin lesions, with satisfactory results. In the literature, there are no clinical studies that contraindicate the administration of HA-based dermal fillers in patients with inflammatory disease.

Do immune checkpoint inhibitors share the same pharmacological feature in the risk of cardiac arrhythmias?

BACKGROUND: Despite the available evidence showing an association between cardiac arrhythmia and Immune Checkpoint Inhibitors (ICIs), few studies have compared this risk between ICIs. OBJECTIVES: We aim to evaluate Individual Case Safety Reports (ICSRs) of ICIs-induced cardiac arrhythmias and compare the reporting frequency of cardiac arrhythmias among ICIs. METHODS: ICSRs were retrieved from the European Pharmacovigilance database (Eudravigilance). ICSRs were classified based on the ICI reported (pembrolizumab, nivolumab, atezolizumab, ipilimumab, durvalumab, avelumab, cemiplimab, and dostarlimab). If more than one ICI was reported, the ICSR was classified as a combination of ICIs. ICSRs of ICI-related arrhythmias were described and the reporting frequency of cardiac arrhythmias was assessed by applying the reporting odds ratio (ROR) and its 95 % confidence interval (95 %CI). RESULTS: A total of 1262 ICSRs were retrieved, of which 147 (11.65 %) were related to combinations of ICIs. A total of 1426 events of cardiac arrhythmias were identified. The three most reported events were atrial fibrillation, tachycardia, and cardiac arrest. Ipilimumab was associated with a reduced reporting frequency of cardiac arrhythmias compared to all other ICIs (ROR 0.71, 95 %CI 0.55-0.92; p = 0.009). Anti-PD1 was associated with a higher reporting frequency of cardiac arrhythmias than anti-CTLA4 (ROR 1.47, 95 %CI 1.14-1.90; p = 0.003). CONCLUSION: This study is the first comparing ICIs for the risk of cardiac arrhythmias. We found that ipilimumab was the only ICI associated with a reduced reporting frequency. Further high-quality studies are needed to confirm our results.

Do peripheral neuropathies differ among immune checkpoint inhibitors? Reports from the European post-marketing surveillance database in the past 10 years.

Although the immunotherapy advent has revolutionized cancer treatment, it, unfortunately, does not spare cancer patients from possible immune-related adverse events (irAEs), which can also involve the peripheral nervous system. Immune checkpoint inhibitors (ICIs), blocking cytotoxic T-lymphocyteassociated protein 4 (CTLA-4), programmed cell death protein 1 (PD-1), or programmed cell death ligand 1 (PD-L1), can induce an immune imbalance and cause different peripheral neuropathies (PNs). Considering the wide range of PNs and their high impact on the safety and quality of life for cancer patients and the availability of large post-marketing surveillance databases, we chose to analyze the characteristics of ICI-related PNs reported as suspected drug reactions from 2010 to 2020 in the European real-world context. We analyzed data collected in the European pharmacovigilance database, Eudravigilance, and conducted a systematic and disproportionality analysis. In our study, we found 735 reports describing 766 PNs occurred in patients treated with ICIs. These PNs included Guillain-Barré syndrome, Miller-Fisher syndrome, neuritis, and chronic inflammatory demyelinating polyradiculoneuropathy. These ADRs were often serious, resulting in patient disability or hospitalization. Moreover, our disproportionality analysis revealed an increased reporting frequency of PNs with tezolizumab compared to other ICIs. Guillain-Barré syndrome is a notable potential PN related to ICIs, as it is associated with a significant impact on patient safety and has had unfavorable outcomes, including a fatal one. Continued monitoring of the safety profile of ICIs in real-life settings is necessary, especially considering the increased frequency of PNs associated with atezolizumab compared with other ICIs.

Initial Phase of Anthracycline Cardiotoxicity Involves Cardiac Fibroblasts Activation and Metabolic Switch.

The application of doxorubicin (DOX) is hampered by cardiotoxicity, with diastolic dysfunction as the earliest manifestation. Fibrosis leads to impaired relaxation, but the mechanisms that operate shortly after DOX exposure are not clear. We asked whether the activation of cardiac fibroblasts (CFs) anticipates myocardial dysfunction and evaluated the effects of DOX on CF metabolism. CFs were isolated from the hearts of rats after the first injection of DOX. In another experiment, CFs were exposed to DOX in vitro. Cell phenotype and metabolism were determined. Early effects of DOX consisted of diastolic dysfunction and unchanged ejection fraction. Markers of pro-fibrotic remodeling and evidence of CF transformation were present immediately after treatment completion. Oxygen consumption rate and extracellular acidification revealed an increased metabolic activity of CFs and a switch to glycolytic energy production. These effects were consistent in CFs isolated from the hearts of DOX-treated animals and in naïve CFs exposed to DOX in vitro. The metabolic switch was paralleled with the phenotype change of CFs that upregulated markers of myofibroblast differentiation and the activation of pro-fibrotic signaling. In conclusion, the metabolic switch and activation of CFs anticipate DOX-induced damage and represent a novel target in the early phase of anthracycline cardiomyopathy.

An in vitro study to assess the effect of hyaluronan-based gels on muscle-derived cells: Highlighting a new perspective in regenerative medicine.

Hyaluronan (HA) is a nonsulfated glycosaminoglycan that has been widely used for biomedical applications. Here, we have analyzed the effect of HA on the rescue of primary cells under stress as well as its potential to recover muscle atrophy and validated the developed model in vitro using primary muscle cells derived from rats. The potentials of different HAs were elucidated through comparative analyses using pharmaceutical grade a) high (HHA) and b) low molecular weight (LHA) hyaluronans, c) hybrid cooperative complexes (HCC) of HA in three experimental set-ups. The cells were characterized based on the expression of myogenin, a muscle-specific biomarker, and the proliferation was analyzed using Time-Lapse Video Microscopy (TLVM). Cell viability in response to H2O2 challenge was evaluated by 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay, and the expression of the superoxide dismutase enzyme (SOD-2) was assessed by western blotting. Additionally, in order to establish an in vitro model of atrophy, muscle cells were treated with tumor necrosis factor-alpha (TNF-α), along with hyaluronans. The expression of Atrogin, MuRF-1, nuclear factor kappa-light-chain-enhancer of activated B-cells (NF-kB), and Forkhead-box-(Fox)-O-3 (FoxO3a) was evaluated by western blotting to elucidate the molecular mechanism of atrophy. The results showed that HCC and HHA increased cell proliferation by 1.15 and 2.3 folds in comparison to un-treated cells (control), respectively. Moreover, both pre- and post-treatments of HAs restored the cell viability, and the SOD-2 expression was found to be reduced by 1.5 fold in HA-treated cells as compared to the stressed condition. Specifically in atrophic stressed cells, HCC revealed a noteworthy beneficial effect on the myogenic biomarkers indicating that it could be used as a promising platform for tissue regeneration with specific attention to muscle cell protection against stressful agents.

AT1-receptor blockade: Protective effects of irbesartan in cardiomyocytes under hypoxic stress.

Hypoxia induces myocardial injury through the activation of inflammatory and oxidative processes. The pivotal role of the renin angiotensin system (RAS) in the pathogenesis of cardiovascular diseases has been firmly established in clinical trials and practice; in fact many experimental and clinical data have highlighted that its inhibition has a cardioprotective role. Activated RAS also stimulates inflammation directly inducing proinflammatory and oxidative gene expression. This study aimed to investigate the protective role of a pre-treatment (10 and 100 µM) with irbesartan on injury induced by 24 h of hypoxia in HL-1 cardiomyocytes; in particular, we have analyzed the natriuretic peptide (BNP) expression, a biomarker able to modulate inflammatory reaction to cardiac injury and some markers involved in oxidative stress and inflammation. Our results demonstrated that a pre-treatment with 100 µM irbesartan significantly increased SOD activity and catalase expression of 15 and 25%, respectively, compared to hypoxic cells (P<0.05). On the other hand, it was able to reduce the release of peroxynitrite and iNOS protein expression of 20 and 50% respectively (P<0.05). In addition irbesartan exerts an anti-inflammatory activity reducing Toll-like receptors (TLRs)-2 and -4 mRNA expression, TNF-alpha expression and activity (20%) and increasing the expression of the cytokine IL-17 (40%) (P<0.05 vs hypoxia). Our findings also showed that BNP induced by ischemia was significantly and in a concentration-dependent manner reduced by irbesartan. The findings of our study demonstrated that the AT1 receptor antagonist irbesartan exerts a protective role in an in vitro hypoxic condition reducing oxidative stress and inflammation.

Role of statins and mevalonate pathway on impaired HDAC2 activity induced by oxidative stress in human airway epithelial cells.

In patients with chronic obstructive pulmonary disease (COPD) the inflammatory response is often steroid-resistant, likely since oxidative stress and cigarette smoking impair histone deacetylase 2 (HDAC2) activity. Since it has been demonstrated that statins may restore the HDAC2 activity in cultured human endothelial cells, the aim of this study was to investigate the effects of statins in reversing the steroid-resistance induced by oxidative stress. We evaluated the effects of simvastatin and dexamethasone on HDAC2 expression and activity, and the role of mevalonate and Rho/ROCK pathways in A549 cells, a human lung type II epithelial cell line stressed with H2O2. Our results documented that H2O2 significantly reduced the HDAC2 expression and activity. In H2O2 treated cells dexamethasone was unable to restore the activity of HDAC2, whereas simvastatin restored both the expression and the activity of this enzyme. Our data also showed that mevalonate reduced the activity of HDAC2 whereas Y27632, a Rho/ROCK inhibitor, had no effect on HDAC2 activity when co-administered with simvastatin. Our data suggest that statins could have the potential to restore corticosteroid sensitivity in A549 cells. The evidences of this study suggest that, although both mevalonate and Rho/ROCK pathways are involved in the detrimental effect elicited by oxidative stress, statins may restore the function and expression of depleted HDAC2 via modulating the mevalonate cascade, at least in A549 cells. In conclusion, the modulation of histone acetyltransferase/deacetylase activity may lead to the development of novel anti-inflammatory approaches to inflammatory lung diseases that are currently difficult to treat.

Inhibition of p110δ PI3K prevents inflammatory response and restenosis after artery injury.

Inflammatory cells play key roles in restenosis upon vascular surgical procedures such as bypass grafts, angioplasty and stent deployment but the molecular mechanisms by which these cells affect restenosis remain unclear. The p110δ isoform of phosphoinositide 3-kinase (PI3K) is mainly expressed in white blood cells. Here, we have investigated whether p110δ PI3K is involved in the pathogenesis of restenosis in a mouse model of carotid injury, which mimics the damage following arterial grafts. We used mice in which p110δ kinase activity has been disabled by a knockin (KI) point mutation in its ATP-binding site (p110δD910A/D910A PI3K mice). Wild-type (WT) and p110δD910A/D910A mice were subjected to longitudinal carotid injury. At 14 and 30 days after carotid injury, mice with inactive p110δ showed strongly decreased infiltration of inflammatory cells (including T lymphocytes and macrophages) and vascular smooth muscle cells (VSMCs), compared with WT mice. Likewise, PI-3065, a p110δ-selective PI3K inhibitor, almost completely prevented restenosis after artery injury. Our data showed that p110δ PI3K plays a main role in promoting neointimal thickening and inflammatory processes during vascular stenosis, with its inhibition providing significant reduction in restenosis following carotid injury. p110δ-selective inhibitors, recently approved for the treatment of human B-cell malignancies, therefore, present a new therapeutic opportunity to prevent the restenosis upon artery injury.

Long-term administration of ranolazine attenuates diastolic dysfunction and adverse myocardial remodeling in a model of heart failure with preserved ejection fraction.

BACKGROUND: To investigate the effects of chronic administration of ranolazine (RAN) on experimental model of heart failure with preserved ejection fraction. METHODS: Seven-weeks old Dahl salt-sensitive rats were fed a high salt diet for 5weeks to induce hypertension. Afterwards, rats continued with a high salt diet and were administered either with vehicle or RAN (20mg/kg/die, ip) for the following 8weeks. Control rats were maintained on a low salt diet. RESULTS: While systolic parameters were not altered, diastolic parameters were changed in high salt animals. Hemodynamic analysis showed a decreased dP/dt min, increased LVEDP, longer time constant and steeper slope of the end-diastolic pressure-volume relationship. Treatment with RAN attenuated these alterations and determined a reduction in mortality. Additionally, the magnitude of myocardial hypertrophy and activation of PI3K/Akt pathway were reduced. Alteration in diastolic compliance as a consequence of elevated myocardial stiffness was confirmed by an increase of collagen deposition and activation of pro-fibrotic TGF-ß/SMAD3/CTGF signaling. These effects were counteracted by RAN. High salt rats had a decrease in SERCA2 and an increase in Na(+)/Ca(2+) exchanger (NCX). Treatment with RAN reduced NCX expression and determined an increment of SERCA2. Moreover, the levels of nitrotyrosine and oxidized dyhydroethidium were higher in high salt rats. RAN induced a decrement of oxidative stress, supporting the concept that reduction in ROS may mediate beneficial effects. CONCLUSIONS: Our findings support the possibility that diastolic dysfunction can be attenuated by RAN, indicating its ability to affect active relaxation and passive diastolic compliance.

G-CSF contributes at the healing of tunica media of arteriotomy-injured rat carotids by promoting differentiation of vascular smooth muscle cells.

Restenosis is a complex pathophysiological disease whose causative mechanisms are not fully understood. Previous studies allowed us to demonstrate the efficacy of bone marrow mesenchymal stromal cells (MSCs) transplantation in limiting the pathophysiological remodeling in a model of arteriotomy-induced (re) stenosis. In the current research we studied the effectiveness of G-CSF treatment on male rate rats that were subjected carotid arteriotomy in order to evaluate a potentially effective non-invasive strategy that recapitulates the MSC-mediated recovery of injured vessels. WKY male rats were subjected carotid arteriotomy and given a nine day treatment (3 days pre- to 6 days post-arteriotomy) with G-CSF or saline. Carotids were harvested 7 and 30 days following arteriotomy (early- and late-phase, respectively). Although morphometrical analysis did not reveal differences in lumen narrowing between G-CSF- and PBS-carotids 30 days following arteriotomy, we detected a noticeable conservative effect of G-CSF treatment on vascular wall morphology. Histological and molecular analysis revealed an increase in cellularity within the tunica media with a concomitant increase of the VSMCs differentiation markers both at early- and late-phases of (re) stenotic response in G-CSF-treated carotids (Sm22-alpha, Myocd, and Smtn). These findings were accompanied by the downregulation of oxidative stress-related genes in G-CSF-injured rats. The effect exerted by G-CSF in our model of arteriotomy-induced (re) stenosis seemed support the recovery of the architecture of the tunica media of injured vessels by: (i) inducing VSMCs differentiation; and (ii) limiting the oxidative-stress response induced by arteriotomy.

Primary and Acquired Resistance of Colorectal Cancer to Anti-EGFR Monoclonal Antibody Can Be Overcome by Combined Treatment of Regorafenib with Cetuximab.

PURPOSE: In colorectal cancer, the activation of the intracellular RAS-RAF and PIK3CA-AKT pathways has been implicated in the resistance to anti-EGFR mAbs. We have investigated the role of regorafenib, an oral multikinase inhibitor, in combination with cetuximab, an anti-EGFR mAb, to overcome anti-EGFR resistance. EXPERIMENTAL DESIGN: We have tested, in vitro and in vivo, the effects of regorafenib in a panel of human colorectal cancer cell lines with a KRAS mutation (SW480, SW620, HCT116, LOVO, and HCT15) or with a BRAF mutation (HT29), as models of intrinsic resistance to cetuximab treatment, and in two human colorectal cancer cell lines (GEO and SW48) that are cetuximab-sensitive, as well as in their derived cells with acquired resistance to cetuximab (GEO-CR and SW48-CR). RESULTS: Treatment with regorafenib determined a dose-dependent growth inhibition in all colorectal cancer cell lines. The combined treatment with cetuximab and regorafenib induced synergistic antiproliferative and apoptotic effects in cetuximab-resistant cell lines by blocking MAPK and AKT pathways. Nude mice were injected s.c. with HCT116, HCT15, GEO-CR, and SW48-CR cells. The combined treatment caused significant tumor growth inhibition. Synergistic antitumor activity of regorafenib plus cetuximab was also observed in an orthotopic colorectal cancer model of HCT116 cells. In particular, the combined treatment induced a significant tumor growth inhibition in the primary tumor site (cecum) and completely prevented metastasis formation. CONCLUSIONS: The combined treatment with cetuximab and regorafenib could be a strategy to overcome resistance to anti-EGFR therapies in metastatic colorectal cancer patients.

Effects of sildenafil on the gastrocnemius and cardiac muscles of rats in a model of prolonged moderate exercise training.

Moderate exercise training improves energetic metabolism, tissue perfusion and induces cardiac and skeletal muscle remodeling. Sildenafil, a potent phosphodiesterase-5 inhibitor used to treat erectile dysfunction, reduces infarct size and increases tissue oxygenation in experimental models of cardiovascular disease. We have evaluated the effects of prolonged moderate exercise training and a repeat administration of sildenafil on the rat gastrocnemius and cardiac muscles. Animals were divided into two groups: sedentary and trained. Each group was subdivided into animals treated with vehicle or with two doses of sildenafil (10 or 15 mg/kg/day) during the last week of training. Physical exercise did not induce cardiac hypertrophy, whereas it increased mRNA levels of the PGC-1α, HIF-1α and VEGF genes, which are involved in mitochondrial biogenesis and angiogenesis, and reduced mRNA levels of FoxO3a, MuRF-1 and Atrogin-1. Sildenafil dose-dependently promoted both angiogenesis, as shown by increased capillary density, and muscle atrophy, as shown by muscle fibre size. These effects were more pronounced in trained animals. Our data confirm the beneficial effects of a moderate and prolonged training on cardiovascular and skeletal systems and document the positive and negative effects of sildenafil on these tissues at doses higher than those used in clinical practice. This report may impact on the use of sildenafil as a substance able to influence sports performance.

Hyperbaric oxygen therapy reduces the toll-like receptor signaling pathway in multiple organ failures.

PURPOSE: Zymosan-induced generalized inflammation is the only experimental model that reproduces characteristics of human multiple organ dysfunction syndrome (MODS). Toll-like receptors (TLRs) are key components in innate immune responses and their signaling pathway is known to activate target genes such as nuclear factor-κB (NF-κB) and cytokines that are involved in inflammation and immune responses. We previously reported that hyperbaric oxygen (HBO) therapy is effective in the treatment of severe zymosan-induced inflammation in MODS. The aim of this study was to investigate the effect of HBO exposure on TLR2 and TLR4 signal transduction and organ dysfunction during MODS induced by zymosan in the rat. METHODS: Male Wistar rats were randomized into four groups and treated as follows: (1) saline solution (control); (2) zymosan; (3) HBO 4 and 11 h after zymosan injection; (4) HBO 4 and 11 h after saline solution injection. Zymosan-induced damage of the lungs, liver, and small intestine was evaluated using histology and biochemistry. The activation of the TLR signaling pathway was measured with Western blot, reverse transcriptase polymerase chain reaction analysis (RT-PCR), and immunohistochemistry. RESULTS: Zymosan induced a severe inflammatory response characterized by the activation of the TLR signaling pathway and by an organ dysfunction. HBO exposure significantly reduced the development of lung, liver, and intestine injury in our experimental model. It also significantly reduced the zymosan-induced expression of TLR2 and TLR4, NF-κB activation, and cytokine production. CONCLUSIONS: Taken together, these results suggest that, by interfering with the TLR pathway, HBO treatment may exert a protective effect against tissue injury caused by zymosan-induced generalized inflammation.

PPARα mediates the anti-inflammatory effect of simvastatin in an experimental model of zymosan-induced multiple organ failure.

BACKGROUND AND PURPOSE: Zymosan-induced non-septic shock is a multi-factorial pathology that involves several organs including the kidneys, liver and lungs. Its complexity and diversity presents a continuing therapeutic challenge. Given their pleiotropic effect, statins could be beneficial in non-septic shock. One of the molecular mechanisms underlying the anti-inflammatory effect of statins involves the peroxisome proliferator-activated receptor (PPAR) α. We used a zymosan-induced non-septic shock experimental model to investigate the role of PPARα in the anti-inflammatory effects of simvastatin. EXPERIMENTAL APPROACH: Effects of simvastatin (5 or 10 mg·kg(-1) i.p.) were analysed in PPARα knock-out (KO) and PPARα wild type (WT) mice after zymosan or vehicle administration. Organ injury in lung, liver, kidney and intestine was evaluated by immunohistology. PPARα mRNA expression and nuclear factor-κB activation were evaluated in all experimental groups, 18 h after study onset. Cytokine levels were measured in plasma, and nitrite/nitrate in plasma and peritoneal exudate. Nitric oxide synthase, nitrotyrosine and poly ADP-ribose were localized by immunohistochemical methods. KEY RESULTS: Simvastatin significantly and dose-dependently increased the zymosan-induced expression of PPARα levels in all tissues analysed. It also dose-dependently reduced systemic inflammation and the organ injury induced by zymosan in lung, liver, intestine and kidney. These effects were observed in PPARαWT mice and in PPARαKO mice. CONCLUSIONS AND IMPLICATIONS: Simvastatin protected against the molecular and cellular damage caused by systemic inflammation in our experimental model. Our results also provide new information regarding the role of PPARα in the anti-inflammatory effects of statins.

Myocardial adeno-associated virus serotype 6-betaARKct gene therapy improves cardiac function and normalizes the neurohormonal axis in chronic heart failure.

BACKGROUND: The upregulation of G protein-coupled receptor kinase 2 in failing myocardium appears to contribute to dysfunctional beta-adrenergic receptor (betaAR) signaling and cardiac function. The peptide betaARKct, which can inhibit the activation of G protein-coupled receptor kinase 2 and improve betaAR signaling, has been shown in transgenic models and short-term gene transfer experiments to rescue heart failure (HF). This study was designed to evaluate long-term betaARKct expression in HF with the use of stable myocardial gene delivery with adeno-associated virus serotype 6 (AAV6). METHODS AND RESULTS: In HF rats, we delivered betaARKct or green fluorescent protein as a control via AAV6-mediated direct intramyocardial injection. We also treated groups with concurrent administration of the beta-blocker metoprolol. We found robust and long-term transgene expression in the left ventricle at least 12 weeks after delivery. betaARKct significantly improved cardiac contractility and reversed left ventricular remodeling, which was accompanied by a normalization of the neurohormonal (catecholamines and aldosterone) status of the chronic HF animals, including normalization of cardiac betaAR signaling. Addition of metoprolol neither enhanced nor decreased betaARKct-mediated beneficial effects, although metoprolol alone, despite not improving contractility, prevented further deterioration of the left ventricle. CONCLUSIONS: Long-term cardiac AAV6-betaARKct gene therapy in HF results in sustained improvement of global cardiac function and reversal of remodeling at least in part as a result of a normalization of the neurohormonal signaling axis. In addition, betaARKct alone improves outcomes more than a beta-blocker alone, whereas both treatments are compatible. These findings show that betaARKct gene therapy can be of long-term therapeutic value in HF.

Inflammatory events in a vascular remodeling model induced by surgical injury to the rat carotid artery.

1.--The aim of our study was to gain insight into the molecular and cellular mechanisms of the inflammatory response to arterial injury in a rat experimental model. 2.--Rats (five for each experimental time) were subjected to brief clamping and longitudinal incision of a carotid artery and monitored for 30 days. Subsequently, Nuclear Factor-kappaB (NF-kappaB) expression was measured by electrophoretic mobility shift assay. Heat shock protein (HSP) 27, HSP47 and HSP70 were evaluated by Western blot. Morphological changes of the vessel wall were investigated by light and electron microscopy. 3.--In injured rat carotid artery NF-kappaB activity started immediately upon injury, and peaked between 2 and 3 weeks later. Western blot showed a significant increase of HSP47 and HSP70 7 days after injury. At 2 weeks postinjury, HSP27 expression peaked. Light microscopy showed a neointima formation, discontinuity of the media layer and a rich infiltrate. Among infiltrating cells electron microscopy identified dendritic-like cells in contact with lymphocytes. 4.--Our model of surgical injury induces a significant inflammatory process characterized by enhanced NF-kappaB activity and HSPs hyperexpression. Dendritic-like cells were for the first time identified as a novel component of tissue repair consequent to acute arterial injury.