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.

Sodium-glucose cotransporter-2 (SGLT2) inhibitors and the reporting of falls and fractures: an european pharmacovigilance analysis.

Background: The risk of falls and bone fractures with sodium-glucose co-transporter-2 (SGLT2) inhibitors has been characterized by conflicting evidence. Therefore, we decided to investigate the reporting probability of falls and fractures by comparing SGLT2 inhibitors with DPP4 inhibitors. Methods A retrospective, pharmacovigilance study of the European database of Individual Case Safety Reports (ICSRs) was conducted. Disproportionality analyses (Reporting Odds Ratio, ROR) were conducted to compare the reporting probability of falls or fracture between treatments. Results A total of 507 ICSRs reporting at least one fall or fracture with SGLT2 inhibitors were identified. The most reported SGLT2 inhibitor was canagliflozin (N = 188; 36.9%), followed by empagliflozin (N = 176; 34.5%), and dapagliflozin (N = 143; 28.0%). A total of 653 events related to fall or bone fracture were reported. Fall was the most reported event (N = 333; 51.0%). Among fractures (N = 320; 49.0%), the most reported were foot fractures (N = 40; 6.1%) and hip fractures (N = 32; 4.9%). SGLT2 inhibitors were associated with a lower reporting probability of fall than DPP4 inhibitors (ROR, 0.66; 95%CI, 0.57-0.78). The lower reporting probability of fall was also observed when the single SGLT2 inhibitor was compared to DPP4 inhibitors: dapagliflozin (ROR, 0.67; 95%CI, 0.53-0.83), canagliflozin (ROR, 0.56; 95%CI, 0.45-0.70), and empagliflozin (ROR, 0.77; 95%CI, 0.63-0.94). For fractures, canagliflozin showed a slightly significant increased reporting when compared with DPP4 inhibitors (not confirmed in the sensitivity analysis), whereas all other comparison showed no statistically significant difference. Conclusion SGLT2 inhibitors were associated with a lower reporting probability of fall than DPP4 inhibitors, in accordance with the reassuring evidence about the safety profile of these drugs. Future researches will help to confirm their long-term safety profile.

COVID-19 Vaccines and Atrial Fibrillation: Analysis of the Post-Marketing Pharmacovigilance European Database.

Atrial fibrillation (AF) has been described in COVID-19 patients. Recently, some case reports and US pharmacovigilance analyses described AF onset as a rare adverse event following COVID-19 vaccination. The possible correlation is unclear. We systematically analyzed the reports of AF related to COVID-19 vaccines collected in the European pharmacovigilance database, EudraVigilance (EV), from 2020 to November 2022. We carried out descriptive and disproportionality analyses. Moreover, we performed a sensitivity analysis, excluding the reports describing other possible alternative AF causes (pericarditis, myocarditis, COVID-19, or other drugs that may cause/exacerbate AF). Overall, we retrieved 6226 reports, which represented only 0.3% of all those related to COVID-19 vaccines collected in EV during our study period. AF reports mainly referred to adults (in particular, >65 years old), with an equal distribution in sex. Reports were mainly related to tozinameran (54.04%), elasomeran (28.3%), and ChAdOx1-S (14.32%). The reported AF required patient hospitalization in 35% of cases and resulted in a life-threatening condition in 10% of cases. The AF duration (when reported) was highly variable, but the majority of the events had a short duration (moda = 24 h). Although an increased frequency of AF reporting with mRNA vaccines emerges from our study, other investigations are required to investigate the possible correlation between COVID-19 vaccination and the rare AF occurrence.

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.

COVID-19 and atrial fibrillation: Intercepting lines.

Almost 20% of COVID-19 patients have a history of atrial fibrillation (AF), but also a new-onset AF represents a frequent complication in COVID-19. Clinical evidence demonstrates that COVID-19, by promoting the evolution of a prothrombotic state, increases the susceptibility to arrhythmic events during the infective stages and presumably during post-recovery. AF itself is the most frequent form of arrhythmia and is associated with substantial morbidity and mortality. One of the molecular factors involved in COVID-19-related AF episodes is the angiotensin-converting enzyme (ACE) 2 availability. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) uses ACE2 to enter and infect multiple cells. Atrial ACE2 internalization after binding to SARS-CoV-2 results in a raise of angiotensin (Ang) II, and in a suppression of cardioprotective Ang(1-7) formation, and thereby promoting cardiac hypertrophy, fibrosis and oxidative stress. Furthermore, several pharmacological agents used in COVID-19 patients may have a higher risk of inducing electrophysiological changes and cardiac dysfunction. Azithromycin, lopinavir/ritonavir, ibrutinib, and remdesivir, used in the treatment of COVID-19, may predispose to an increased risk of cardiac arrhythmia. In this review, putative mechanisms involved in COVID-19-related AF episodes and the cardiovascular safety profile of drugs used for the treatment of COVID-19 are summarized.

Dapagliflozin protects the kidney in a non-diabetic model of cardiorenal syndrome.

Cardiorenal syndrome encompasses a spectrum of disorders involving heart and kidney dysfunction, and sharing common risk factors, such as hypertension and diabetes. Clinical studies have shown that patients with and without diabetes may benefit from using sodium-glucose cotransporter 2 inhibitors to reduce the risk of heart failure and ameliorate renal endpoints. Because the underlying mechanisms remain elusive, we investigated the effects of dapagliflozin on the progression of renal damage, using a model of non-diabetic cardiorenal disease. Dahl salt-sensitive rats were fed a high-salt diet for five weeks and then randomized to dapagliflozin or vehicle for the following six weeks. After treatment with dapagliflozin, renal function resulted ameliorated as shown by decrease of albuminuria and urine albumin-to-creatinine ratio. Functional benefit was accompanied by a decreased accumulation of extracellular matrix and a reduced number of sclerotic glomeruli. Dapagliflozin significantly reduced expression of inflammatory and endothelial activation markers such as NF-κB and e-selectin. Upregulation of pro-oxidant-releasing NADPH oxidases 2 and 4 as well as downregulation of antioxidant enzymes were also counteracted by drug treatment. Our findings also evidenced the modulation of both classic and non-classic renin-angiotensin-aldosterone system (RAAS), and effects of dapagliflozin on gene expression of ion channels/transporters involved in renal homeostasis. Thus, in a non-diabetic model of cardiorenal syndrome, dapagliflozin provides renal protection by modulating inflammatory response, endothelial activation, fibrosis, oxidative stress, local RAAS and ion channels.

Streptozotocin-Induced Type 1 and 2 Diabetes Mellitus Mouse Models Show Different Functional, Cellular and Molecular Patterns of Diabetic Cardiomyopathy.

The main cause of morbidity and mortality in diabetes mellitus (DM) is cardiovascular complications. Diabetic cardiomyopathy (DCM) remains incompletely understood. Animal models have been crucial in exploring DCM pathophysiology while identifying potential therapeutic targets. Streptozotocin (STZ) has been widely used to produce experimental models of both type 1 and type 2 DM (T1DM and T2DM). Here, we compared these two models for their effects on cardiac structure, function and transcriptome. Different doses of STZ and diet chows were used to generate T1DM and T2DM in C57BL/6J mice. Normal euglycemic and nonobese sex- and age-matched mice served as controls (CTRL). Immunohistochemistry, RT-PCR and RNA-seq were employed to compare hearts from the three animal groups. STZ-induced T1DM and T2DM affected left ventricular function and myocardial performance differently. T1DM displayed exaggerated apoptotic cardiomyocyte (CM) death and reactive hypertrophy and fibrosis, along with increased cardiac oxidative stress, CM DNA damage and senescence, when compared to T2DM in mice. T1DM and T2DM affected the whole cardiac transcriptome differently. In conclusion, the STZ-induced T1DM and T2DM mouse models showed significant differences in cardiac remodeling, function and the whole transcriptome. These differences could be of key relevance when choosing an animal model to study specific features of DCM.

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.

Evaluation of unsulfated biotechnological chondroitin in a knee osteoarthritis mouse model as a potential novel functional ingredient in nutraceuticals and pharmaceuticals.

Osteoarthritis is a very disabling disease that can be treated with both non-pharmacological and pharmacological approaches. In the last years, pharmaceutical-grade chondroitin sulfate (CS) and glucosamine emerged as symptomatic slow-acting molecules, effective in pain reduction and improved function in patients affected by osteoarthritis. CS is a sulfated glycosaminoglycan that is currently produced mainly by extraction from animal tissues, and it is commercialized as a pharmaceutical-grade ingredient and/or food supplement. However, public concern on animal product derivatives has prompted the search for alternative non-extractive production routes. Thus, different approaches were established to obtain animal-free natural identical CS. On the other hand, the unsulfated chondroitin, which can be obtained via biotechnological processes, demonstrated promising anti-inflammatory properties in vitro, in chondrocytes isolated from osteoarthritic patients. Therefore, the aim of this study was to explore the potential of chondroitin, with respect to the better-known CS, in an in vivo mouse model of knee osteoarthritis. Results indicate that the treatment with biotechnological chondroitin (BC), similarly to CS, significantly reduced the severity of mechanical allodynia in an MIA-induced osteoarthritic mouse model. Decreased cartilage damage and a reduction of inflammation- and pain-related biochemical markers were also observed. Overall, our data support a beneficial activity of biotechnological unsulfated chondroitin in the osteoarthritis model tested, thus suggesting BC as a potential functional ingredient in pharmaceuticals and nutraceuticals with the advantage of avoiding animal tissue extraction.

Antimicrobial Peptides Human Beta-Defensin-2 and -3 Protect the Gut During Candida albicans Infections Enhancing the Intestinal Barrier Integrity: In Vitro Study.

The intestinal mucosa is composed of a monolayer of epithelial cells, which is highly polarized and firmly united to each other thanks to the presence of proteins complexes, called Tight junctions (TJs). Alteration of the mucus layer and TJs causes an increase in intestinal permeability, which can lead to a microbial translocation and systemic disorders. Candida albicans, in addition to its role of commensal, is an opportunistic pathogen responsible for disseminated candidiasis, especially in immunocompromised subjects where the dysbiosis leads to damage of the intestinal mucosal barrier . In this work, we used a line of intestinal epithelial cells able to stably express the genes that encodes human beta defensin-2 (HBD-2) and -3 (HBD-3) to monitor the invasion of C. albicans in vitro. Defensins are a group of antimicrobial peptides (AMPs) found in different living organisms, and are involved in the first line of defense in the innate immune response against pathogens. The results obtained show that the presence of antimicrobial peptides improves the expression of TJs and increases the Trans Epithelial Electrical Resistence value. In addition, the invasive ability of C. albicans in transfected cells is significantly reduced, as well as the expression levels of genes involved in the apoptotic pathway. Through the study of interaction between antimicrobial peptides and microbiota we will be able in the future to better understand the mechanisms by which they exert the host defense function against intestinal pathogens.

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.

Protective effect of piceatannol and bioactive stilbene derivatives against hypoxia-induced toxicity in H9c2 cardiomyocytes and structural elucidation as 5-LOX inhibitors.

Stilbenes with well-known antioxidant and antiradical properties are beneficial in different pathologies including cardiovascular diseases. The present research was performed to investigate the potential protective effect of resveratrol (1) and piceatannol (2), against hypoxia-induced oxidative stress in the H9c2 cardiomyoblast cell line, and the underlying mechanisms. Compounds 1 and 2 significantly inhibited the release of peroxynitrite and thiobarbituric acid levels at na no- or submicromolar concentrations, and this effect was more evident in piceatannol-treated cells, that significantly increased MnSOD protein level in a concentration dependent manner. Furthermore, since piceatannol, which is far less abundant in natural sources, displayed a higher bioactivity than the parent compound, we hereby report on a very fast synthesis and detailed structure-based design of a focused stilbene library. Finally, taking into account that hypoxia-induced ROS accumulation also increases expression and activity of 5-lipoxygenase (5-LOX) with production of leukotrienes, we have disclosed structural key factors crucial for 5-LOX activity. Among the synthesized analogues ( 3-7), compound 7 was the most effective in improving cardiomyocytes viability and in 5-LOX inhibition. In conclusion, modeling and experimental studies provided the basis for further optimization of stilbene analogues as multi-target inhibitors of the inflammatory and oxidative pathway.

Addition of the Aldose Reductase Inhibitor Benzofuroxane Derivative BF-5m to Prolonged and Moderate Exercise Training Enhanced Protection of the Rat Heart From Type-1 Diabetes.

Moderate exercise training may not be sufficient to exert beneficial effects on the cardiovascular system because of the long-term multifactorial etiology of diabetic complications. The addition of a proper pharmacological tool to the physical exercise should improve the outcomes of the diabetic damage. Here it is shown that 8 weeks exercise training of type 1 diabetic Sprague-Dawley (SD) rats resulted in a significantly increased heart rate, a 14% increase in the left ventricular ejection fraction (LVEF) increased plasma insulin levels and a 13% decrease in plasma glucose with respect to sedentary animals. The training also resulted in a 22% reduction in cardiac QT interval from a diabetic sedentary value of 185 ± 19 ms. Treatment of trained rats with the new antioxidant and NO-releasing aldose reductase 2 inhibitor 5(6)-(benzo[d]thiazol-2-ylmethoxy) benzofuroxane BF-5m, 20 mg/kg/day, added a further and significant (P < 0.01 vs. sedentary) increase of the LVEF up to 38% at 8 week time point. The long QT interval recorded in trained rats was reduced to further 12% by addition to the training of pharmacological treatment with 20 mg/kg/day BF-5m. At this time, the association of the two treatments improved the expression into the cardiac tissue of sarcoplasmic reticulum Ca2+ ATPase 2 (SERCA2) and manganese superoxide dismutase (MnSOD), and reduced the fibrosis.

Cardioprotective effect of a moderate and prolonged exercise training involves sirtuin pathway.

AIM: To investigate the cardioprotective effects of prolonged and moderate exercise training on cellular and molecular events early after myocardial infarction. MATERIALS AND METHODS: Male Wistar rats were divided in sedentary or exercised group; both groups underwent to a myocardial infarction. All the molecular and immunohistochemical analyses on hearts of sedentary and exercised rats were performed 48 h after surgical procedure. SIRT1 and SIRT3 expression were measured and two of the pathways activated by sirtuins, p53-induced apoptosis and Forkhead boxO (FOXO)3a-induced oxidative stress, were investigated. All the experiments were performed also in presence of the SIRT inhibitor, EX527. KEY FINDINGS: Fourty-eight hours post myocardial infarction, exercise training induced the activation of SIRT1 and SIRT3 pathway reducing cardiomyocytes apoptosis and oxidative damage. Molecular data were confirmed by immunohistochemical evaluations. These effects are more evident in border infarcted zone than in the remote myocardium. SIGNIFICANCE: Exercise training is a non-pharmacological prevention strategy in cardiovascular diseases and the sirtuins family seems to be as novel and attractive target in cardioprotection.

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.