P24 WEAREBLE CARDIOVERTER – DEFIBRILLATOR : UTILITY AND USER FRIENDLINESS

Background

Worldwide, cardiovascular disease are still a major mode of death, being sudden arrhythmic death (SCD)25 % of total death. Implantable cardioverter defibrillator (ICD) is an effective weapon for SCD prevention in high risk patients with reasonable expectation of survival with good functional status for >1 year. However sometimes the risk of SCD can be transient, so the use of a wearable cardioverter defibrillator (WCD) is considered.

Methods

We considered consecutively 40 patients discharged from our cardiology department of Piacenza and Castel san Giovanni that, for potentially transient high risk of SCD, weared a WCD from August 2017 to September 2021, after a systematic education session lasting 30 – 45 minutes. They are followed through remote monitoring.

Results

Out of 40 patients, with average age 66 years old and average left ventricular ejection fraction (LVEF) 29%, 88% were males, 70 % suffered from arterial hypertension, 32% diabetes mellitus, 17,5 % peripheral vascular disease, 35 % chronic renal failure, 55% heart failure, 7,5% previous stroke. 56% of these patients weared WCD for severe systolic disfunction in ischemic cardiac disease after recent myocardial infarction, after percutaneous coronary intervention or coronary artery bypass graft, 7% after removal of an infected ICD, 9 % whilst awaiting completion of diagnostic tests (chanalopathies/right arrhythmogenic ventricular cardiomyopathy), 34% after newly diagnosed cardiomyopathy.The patients were discharged in high risk mode of SCD with WCD protection.The average wearing time of WCD was 51 days and 22,98 hours daily. We received 953 trasmissions, with 21 events: 7 ventricular tachicardia, 4 Sopraventricular tachicardia and 5 T wave oversensing .Neither inappropriate shock and neither death were detected .After wearing time and after clinical evaluation, only 52% of patients were subjected to ICD implantation.

Conclusions

In our experience we may consider that WCD use is effective, safe and with a good adherence in all patients, considering wearing time. The WCD allows saving resources with less hospitalization time.

C7 WEARABLE CARDIOVERTER – DEFIBRILLATOR IN PATIENTS WITH HIGH RISK OF SUDDEN CARDIAC DEATH: IS IT USEFUL A PATIENT SELECTION?

Background

The wearable cardioverter defibrillator (WCD) is considered in patients with increased risk of sudden cardiac death (SDC), in which implanted cardiac defibrillator (ICD) is temporary not definitively indicated. A few registry confirmed efficacy and safety of WCD and left ventricular ejection fraction recovery (LEVS)after wearing time.

Methods

We considered in our study 40 consecutively patients that used WCD in Piacenza and Castel San Giovanni Cardiology Department from August 2017 to September 2021 with recent acute myocardial infarction, newly diagnosed cardiomyopathy, primary arrhythmias syndrome awaiting diagnostic completation. They were followed by remore monitoring. The primary outcome were: the need of ICD implantation or not indication to ICD at the of the wearing time, We analyzed clinical variables related to primary outcome.

Results

Out of 40 patients, average age 66 years, average LEVS media 29%±12,5,88% were males, 32% suffered from diabetes mellitus, 35% renal failure, 55% acute and chronic heart failure, 10% previous ischemic stroke, 17% atrial fibrillation (AF), 12% cardiac arrest (ACC) after STEMI onset, 20% ventricular tachicardia (VT). 27% of these patients took amiodarone,92% beta blockers and 82% ACEi.The average wearing time of WCD was 51 days and 22,96 hours dailyAt the end of this period 48% of patients didn‘t receive ICD implantation for increasing LEVS.We evaluated clinical variables related to primary outcome with Chi Square test and Student’s t test.There weren’t significant difference regarding primary outcome between ischemic disease and other cardiophaties. The presence of AF, previous stroke, renal failure, hypertension, diabetes mellitus was more but not significant in ICD group. No significant age difference(66.8±14.1 vs 66.3±11.8, p = 0,6) neither FEVS (29.4±11.6 vs 29.5±12.7, p = 0,8) was in patients that received ICD versus not received .The clinical variables related to primary outcome only were: ACC after STEMI onset and amiodarone therapy.

Conclusions

In our study of patients with WCD, the percentage of LEVS increase is consistent with European registries. A few clinical variables may be related to ICD indication. Further studies can be useful to identify patients who need more of WCD for a lack of LEVS improvement.

Prognosis implications of quantified mitral regurgitation stratified by left atrial function in HFrEF population

Funding Acknowledgements

Type of funding sources: None.

BACKGROUND

The debate about the independent prognostic responsibility of functional mitral regurgitation (FMR) is still in turmoil. Growing findings about the predictive role of left atrial (LA) function are emerging in several scenarios.

PURPOSE

This study aims to define FMR linkage to cardiovascular (CV) outcomes and the interplay with LA function in a prospective cohort of consecutive heart failure patients with reduced ejection fraction (HFrEF).

METHODS

286 consecutive outpatients with chronic HFrEF were enrolled. FMR was quantified by effective regurgitant orifice area (EROA). Global peak atrial longitudinal strain (PALS) was measured by speckle tracking echocardiography (STE). The primary endpoint was defined as a composite of congestive HF hospitalization and CV death.

RESULTS

The majority (81%) of patients were men (mean age: 67 ± 11 years, mean LVEF: 32 ± 6%). The median global PALS was 17.7% ranging from 2.7% to 49.2%. FMR was quantifiable in 240 (84%) patients. During a median follow-up period of 6.4 (IQR 3.9-7.7) years, the primary endpoint occurred in 88 (31%) patients (35 HF admissions, and 53 deaths). EROA showed independent prediction for the primary endpoint (HR 1.30 [1.05-1.57], P = 0.01). The spline modeling of the risk by EROA values showed an excess event risk starting at about the EROA value of 0.1 cm2 (Figure 1). There was a remarkable graded association between the EROA strata, even if tested per 0.1 cm2 increase, and the risk of congestive HF hospitalization and CV death (P = 0.0004). Any FMR grade presenting with reduced LA function (PALS < 14%) was associated with dismal outcome (event rate of 63 ± 10% for EROA exceeding 0.3 cm2 and 49 ± 6% for EROA ≥0.1 cm2 at 5 years). Conversely, the presence of EROA ≥0.1 in the context of preserved global PALS showed a better outcome (Figure 2).

CONCLUSIONS

Our results refine the independent association between FMR and CV outcome among HFrEF outpatients. The risk of CV events starts at a low EROA value, reaching a severe level above the threshold of 0.3 cm2. Within a moderate EROA range, the LA function mitigates the clinical consequences of the mitral regurgitation, providing measurable proof of the interplay between the regurgitation and the LA compliance. Abstract Figure 1  Abstract Figure 2

Correction: Cigarette Smoke Affects Keratinocytes SRB1 Expression and Localization via H2O2 Production and HNE Protein Adducts Formation

[This corrects the article DOI: 10.1371/journal.pone.0033592.].

P2875Comparison between ejection fraction, global longitudinal strain, mechanical dispersion and delta contraction duration in predicting first and subsequent arrhythmic events in ICD patients

Background

According to current guidelines, left ventricular ejection fraction (LVEF) is currently the most important parameter for primary prevention of sudden cardiac death in patients with structural heart disease. Unfortunately, LVEF has low sensitivity in detecting arrhythmic events and presents a significant intra- and inter-operator variability. For these reasons, alternative predictors in patients with structural heart disease are being sought. Among those, speckle-tracking derived parameters such as global longitudinal strain (GLS), mechanical dispersion (MD), and delta contraction duration (DCD) have been proposed as better alternatives.

Purpose

To assess speckle-tracking derived parameters as predictors of first and subsequent arrhythmic events in implantable cardioverter-defibrillator (ICD) patients with structural heart disease, and to compare their performance with LVEF.

Methods

Prospective, observational study enrolling all consecutive patients with structural heart disease admitted for an ICD implant. Patients not followed by a home-monitoring system were excluded. 2D speckle-tracking analysis was used to derive GLS, MD, and DCD of all patients at enrolment. Home monitoring was checked weekly in order to detect all ventricular arrhythmias (VA) and ICD therapies. A recurrent-event statistical approach (Prentice, Williams, and Peterson model) was applied in order to evaluate subsequent events after the first ones.

Results

Two-hundred-and-three patients were consecutively enrolled and followed-up for a median follow-up of 2.2 years. Kaplan-Meier curves showed an increased risk of ATP or shock (Log-rank p=0.003) and VAs (Log-rank p=0.001) associated with lower quartiles of GLS (Figure 1). An impaired GLS was independently associated with an increased risk for the first ICD therapy (HR 1.94; 95% CI 1.30–2.91; p=0.001), and for the first VA (HR 1.42; 95% CI 1.01–1.98; p=0.04). GLS impairment was not significantly associated with an increased risk of recurrent ICD therapies or VAs. LVEF, MD and DCD were not associated with an increased risk of first, second and third ICD therapy or VA.

Conclusions

Impaired GLS is associated with an increased risk of VAs and appropriate ICD therapies in a consecutive, “real-world”, unselected population of remote-monitored patients with structural heart disease, although it does not seem reliable in predicting further arrhythmic event after the first one. LVEF, MD, and DCD do not predict first or subsequent arrhythmic events in ICD patients with structural heart disease.

Acknowledgement/Funding

Marche Polytechnic University

Tropospheric ozone affects SRB1 levels via oxidative post-translational modifications in lung cells

Exposure to air pollution is associated with increased respiratory morbidities and susceptibility to lung dysfunction. Ozone (O₃) is commonly recognized as one of the most noxious air pollutant and has been associated with several lung pathologies. It has been demonstrated that decreased lung disorder severity and incidence are connected with the consumption of a diet rich in fruits and vegetables, suggesting that higher intake of dietary micronutrients and phytoactive compounds can be beneficial. However, dietary supplementation - i.e. vitamin E (α-tocopherol) or vitamin A - has not always been effective in improving pulmonary function. Recently, research on the role of nutritional antioxidants on human health has focused more on studying their uptake at the cellular level rather than their effective ability to scavenge reactvive oxygen species (ROS). The Scavenger Receptor B1 (SRB1) has been shown to play a prominent role in the uptake, delivery and regulation of vitamin E in the lung. Given the importance of SRB1 in maintaining lung tissue in a healthy condition, we hypothesize that its expression could be modulated by pollution exposure, which thus could indirectly affect the uptake and/or delivery of lipophilic substances, such as vitamin E. To characterize the molecular mechanism involved in the redox modulation of SRB1, its cellular levels were assessed in human alveolar epithelial cells after O₃ exposure. The results demonstrated that O₃ induced the loss of SRB1 protein levels. This decline seems to be driven by hydrogen peroxide (H₂O₂) as a consequence of an increased activation of cellular NADPH oxidase (NOX), as demonstrated by the use of NOX inhibitors or catalase that reversed this effect. Furthermore, O₃ caused the formation of SRB1-aldheyde adducts (4-hydroxy-2-nonenal) and the consequent increase of its ubiquitination, a mechanism that could account for SRB1 protein loss.

SR-B1 involvement in keratinocytes in vitro wound closure

Skin represents the most extended organ of human body, having as main function the protection of our body from outdoor stressors. Its protective ability is compromised when the skin is disrupted as a consequence of mechanical insults. For this purpose, cutaneous tissue is equipped with an efficient and fine mechanism involved in repairing the wounded area. Among the numerous players that take part in the wound healing process, SR-B1 has been recently shown to have a role in keratinocyte re-epithelialization. SR-B1 is a mediator of cholesterol uptake from HDLs, whereas it is implicated in other cellular processes such as vitamins absorption, vesicle trafficking or pathogen identification. The aim of this study was to investigate the mechanisms involved in SR-B1 role in skin wound closure. Our in vitro data demonstrated that SR-B1 influenced keratinocyte proliferation and migration through a downregulation of nuclear cyclin D1 levels and active MMP9 expression respectively possibly in an NF-kB-dependent mechanism. In addition, SR-B1 was also able to modulate keratinocyte morphology into a pro-migratory cytoskeleton rearrangement. The present in vitro study suggests a new role of SRB1 as a possible new key player in cutaneous wound healing mechanism.

Resveratrol: from diet to topical usage

The stilbene derivative resveratrol (3,5,4'-trihydroxy-stilbene; RESV) has become the subject of interest of many researchers and the pharmaceutical industries due to its well-acclaimed beneficial biological activities. Although earlier research tended to focus on the effects of RESV on cardiovascular disorders, many other studies have described the beneficial effects of RESV in the areas of cancer chemoprevention and inflammation and interest of researchers on this compound is still increasing. It is now well accepted that the effect of RESV is not just due to its so called "antioxidant" activity but mainly (if not only) because of the ability of this compound to trigger cell signaling pathways and gene expression involved in cellular defense systems. Many "in vitro" studies on RESV did not take into account that although its oral absorption is about 75% it undergoes rapid metabolism and the concentration in the blood stream is almost undetectable. For this reason interest in the topical usage of RESV by cosmeceutical skin care brands has exponentially increased in the last decade reporting in general very promising results on its beneficial effect in protecting the skin from outdoor insults, but there is still some controversy on its topical usage mainly surrounding the concentration used. Therefore, more basic research on the topical application of RESV should be performed to better understand the way it prevents cutaneous damage and whether it could be recommended as a preventive skin aging agent for all skin insults.

Modulation of cutaneous scavenger receptor B1 levels by exogenous stressors impairs "in vitro" wound closure

Scavenger receptor B1 (SR-B1) is a trans-membrane protein, involved in tissue reverse cholesterol transport. Several studies have demonstrated that SR-B1 is also implicated in other physiological processes, such as bacteria and apoptotic cells recognition and regulation of intracellular tocopherol and carotenoids levels. Among the tissues where it is localized, SR-B1 has been shown to be significantly expressed in human epidermis. Our group has demonstrated that SR-B1 levels are down-regulated in human cultured keratinocytes by environmental stressors, such as cigarette smoke, via cellular redox imbalance. Our present study aimed to investigate whether such down-regulation was confirmed in a 3D skin model and under other environmental challengers such as particulate matter and ozone. We also investigated the association between oxidation-induced SR-B1 modulation and impaired wound closure. The data obtained showed that not only cigarette, but also the other environmental stressors reduced SR-B1 expression in epidermal cutaneous tissues and that this effect might be involved in impaired wound healing.

In vitro vascular toxicity of tariquidar, a potential tool for in vivo PET studies

The P-glicoprotein (P-gp) inhibitor tariquidar is used to detect functional alterations of blood brain barrier pumps in PET imaging. The doses required, however, up to 4-fold higher than those already used in clinical trials to reverse multidrug resistance, cause syncopal episode and hypotension. Therefore, the effects of these doses toward the vasculature were investigated and an in-depth analysis of tariquidar-mediated effects on A7r5 and EA.hy926 cells viability, on the mechanical activity of freshly and cultured rat aorta rings and on L-type Ca²⁺ current [I_Ca(L)] of A7r5 cells has been performed. In both A7r5 and EA.hy926 cells, tariquidar was not cytotoxic up to 1μM concentration. On the contrary, at 10μM, it caused apoptosis already after 24h treatment. In fresh aorta rings, 10μM tariquidar partially relaxed phenylephrine-, but not 60mM K⁺ (K60)-induced contraction. In rings treated with 10μM tariquidar for 7days, the contractile response to both phenylephrine and K60 remained unchanged. Finally, tariquidar did not modify I_Ca1.2 intensity and kinetics. In conclusion, Tariquidar might exert both cytotoxic and acute, weak vascular effects at concentrations comparable to those employed in PET imaging. This implies that caution should be exercised when using it as diagnostic tool.

SRB1 as a new redox target of cigarette smoke in human sebocytes

For its critical location, the skin represents the major interface between the body and the environment, therefore is one of the major biological barriers against the outdoor environmental stressors. Among the several oxidative environmental stressors, cigarette smoke (CS) has been associated with the development and worsening of many skin pathologies such as acne, dermatitis, delayed wound healing, aging and skin cancer. In our previous work we have demonstrated that CS is able to affect genes involved in skin cholesterol trafficking, among which SRB1, a receptor involved in the uptake of cholesterol from HDL, seems to be very susceptible to the oxidative stress induced by CS. In the present work we wanted to investigate the presence of SRB1 in human sebocytes and whether CS can affect cholesterol cellular uptake via the redox modulation of SRB1. By using a co-culture system of keratinocytes/sebocytes, we found that CS exposure induced a SRB1 protein loss without affecting sebocytes viability. The decrease of SRB1 levels was a consequence of SRB1/HNE adducts formation that leads to SRB1 ubiquitination and degradation. Moreover, the CS-induced loss of SRB1 induced an alteration of sebocytes lipid content, also demonstrated by cholesterol quantification in SRB1 siRNA experiments. In conclusion, exposure to CS, induced SRB1 post-translational modifications in sebocytes and this might affect sebocytes/skin functionality.

Proteomic analysis of 4-hydroxynonenal and nitrotyrosine modified proteins in RTT fibroblasts

Rett syndrome (RTT) is a pervasive developmental disorder, primarily affecting girls with a prevalence of 1 in every 10,000 births. A clear etiological factor present in more than 90% of classical RTT cases is the mutation of the gene encoding methyl-CpG-binding protein 2 (MECP2). Recent work from our group was able to shown a systemic oxidative stress (OxS) in these patients that correlates with the gravity of the clinical features. Using freshly isolated skin fibroblasts from RTT patients and healthy subjects, we have performed a two-dimensional gel electrophoresis in order to evidence the oxidative modifications of proteins with special focus on the formation of protein adducts with 4-hydroxynonenal (4-HNE PAs)-a major secondary product of lipid peroxidation- and Nitrotyrosine, a marker derived from the biochemical interaction of nitric oxide (NO) or nitric oxide-derived secondary products with reactive oxygen species (ROS). Then, oxidatively modified spots were identified by mass spectrometry, LC-ESI-CID-MS/MS. Our results showed that 15 protein spots presented 4-HNE PAs and/or nitrotyrosine adducts in fibroblasts proteome from RTT patients compared to healthy control cells. Post-translationally modified proteins were related to several functional categories, in particular to cytoskeleton structure and protein folding. In addition, clear upregulated expression of the inducible NO synthase (iNOS) with high nitrite levels were observed in RTT fibroblasts, justifying the increased nitrotyrosine protein modifications. The present work describes not only the proteomic profile in RTT fibroblasts, but also identifies the modified proteins by 4-HNE and nitrotyrosine. Of note, for the first time, it appears that a dysregulation of NO pathway can be associated to RTT pathophysiology. In conclusion, the evidence of a wide range of proteins able to forms adducts with 4-HNE, Nitrotyrosine or with both confirms the possible alteration of several aspects of cellular functions that well correlates to the complex clinical features of RTT patients.

Design and Synthesis of New Transient Receptor Potential Vanilloid Type-1 (TRPV1) Channel Modulators: Identification, Molecular Modeling Analysis, and Pharmacological Characterization of the N-(4-Hydroxy-3-methoxybenzyl)-4-(thiophen-2-yl)butanamide, a Small Molecule Endowed with Agonist TRPV1 Activity and Protective Effects against Oxidative Stress

4-(Thiophen-2-yl)butanoic acid was identified as a cyclic substitute of the unsaturated alkyl chain of the natural ligand, capsaicin. Accordingly, a new class of amides was synthesized in good yield and high purity and their molecular recognition against the target was investigated by means of docking experiments followed by molecular dynamics simulations, in order to rationalize their geometrical and thermodynamic profiles. The pharmacological properties of these new compounds were expressed as activation (EC50) and desensitization (IC50) potencies. Several compounds were found to activate TRPV1 channels, and in particular, derivatives 1 and 10 behaved as TRPV1 agonists endowed with good efficacy as compared to capsaicin. The most promising compound 1 was also evaluated for its protective role against oxidative stress on keratinocytes and differentiated human neuroblastoma cell lines expressing the TRPV1 receptor as well as for its cytotoxicity and analgesic activity in vivo.

Skin Damage Mechanisms Related to Airborne Particulate Matter Exposure

Epidemiological studies suggest a correlation between increased airborne particulate matter (PM) and adverse health effects. The mechanisms of PM-health effects are believed to involve oxidative stress and inflammation. To evaluate the ability of PM promoting skin tissue damage, one of the main organs exposed to outdoor pollutants, we analyzed the effect of concentrated ambient particles (CAPs) in a reconstructed human epidermis (RHE) model. RHE tissues were exposed to 25 or 100 µg/ml CAPs for 24 or 48 h. Data showed that RHE seems to be more susceptible to CAPs-induced toxicity after 48 h exposure than after 24 h. We found a local reactive O(2) species (ROS) production increase generated from metals present on the particle, which contributes to lipids oxidation. Furthermore, as a consequence of altered redox status, NFkB nucleus translocation was increase upon CAPs exposure, as well as cyclooxygenase 2 and cytochrome P450 levels, which may be involved in the inflammatory response initiated by PM. CAPs also triggered an apoptotic process in skin. Surprisingly, by transition electron microscopy analysis we showed that CAPs were able to penetrate skin tissues. These findings contribute to the understanding of the cutaneous pathophysiological mechanisms initiated by CAPs exposure, where oxidative stress and inflammation may play predominant roles.

Antitubulinic effect of New Fluorazone Derivatives on Melanoma Cells

Microtubules are composed by α- and β-tubulin polypeptides. α-tubulin undergoes a reversible posttranslational modification whereby the C-terminal tyrosine residue is removed (Glu-tubulin) and re-added (Tyrtubulin). Recent studies have shown that α-tubulin tyrosine residues can be nitrated and the incorporation of NO2Tyr into the C-terminus of Glu-tubulin forms a complex that blocks the tyrosination/detyrosination cycle, an event that can compromise protein/enzyme functions, such as cell division. Since many studies demonstrated that Glu-tubulin levels increase in cancer, the aim of the present study was to investigate the effect of new drugs, fluorazone derivatives (K1-K2-K9-K10-K11), on the proliferation of melanoma cells. Our results demonstrated that these drugs, except for K2, were able to inhibit cellular proliferation without exhibiting cytotoxicity. The anti-proliferative effect was accompanied by the decrease of Glu-tubulin levels and the increase of its nitration. This effect seems to be a consequence of NO2 induction and NO2Tyr ligation to Glu-tubulin. Collectively, these results, showing that the fluorazone derivatives, by promoting NO2Tyr incorporation into α-tubulin, are able to arrest the cycle of detyrosination/tyrosination and to inhibit cell proliferation, offer new perspectives for the possible usage of these drugs, alone or in combination, as non-toxic, anti-proliferative agents in melanoma.

Alteration of serum lipid profile, SRB1 loss, and impaired Nrf2 activation in CDKL5 disorder

CDKL5 mutation is associated with an atypical Rett syndrome (RTT) variant. Recently, cholesterol homeostasis perturbation and oxidative-mediated loss of the high-density lipoprotein receptor SRB1 in typical RTT have been suggested. Here, we demonstrate an altered lipid serum profile also in CDKL5 patients with decreased levels of SRB1 and impaired activation of the defensive system Nrf2. In addition, CDKL5 fibroblasts showed an increase in 4-hydroxy-2-nonenal- and nitrotyrosine-SRB1 adducts that lead to its ubiquitination and probable degradation. This study highlights a possible common denominator between two different RTT variants (MECP2 and CDKL5) and a possible common future therapeutic target.

Vitamin C Compound Mixtures Prevent Ozone-Induced Oxidative Damage in Human Keratinocytes as Initial Assessment of Pollution Protection

Introduction

One of the main functions of cutaneous tissues is to protect our body from the outdoor insults. Ozone (O₃) is among the most toxic stressors to which we are continuously exposed and because of its critical location, the skin is one of the most susceptible tissues to the oxidative damaging effect of O₃. O₃ is not able to penetrate the skin, and although it is not a radical per se, the damage is mainly a consequence of its ability to induce oxidative stress via the formation of lipid peroxidation products.

Aim of Study

In this study we investigated the protective effect of defined “antioxidant” mixtures against O₃ induced oxidative stress damage in human keratinocytes and understand their underlying mechanism of action.

Results

Results showed that the mixtures tested were able to protect human keratinocytes from O₃-induced cytotoxicity, inhibition of cellular proliferation, decrease the formation of HNE protein adducts, ROS, and carbonyls levels. Furthermore, we have observed the decreased activation of the redox sensitive transcription factor NF-kB, which is involved in transcribing pro-inflammatory cytokines and therefore constitutes one of the main players associated with O₃ induced skin inflammation. Cells exposed to O₃ demonstrated a dose dependent increase in p65 subunit nuclear expression as a marker of NF-kB activation, while pre-treatment with the mixtures abolished NF-kB nuclear translocation. In addition, a significant activation of Nrf2 in keratinocytes treated with the mixtures was also observed.

Conclusion

Overall this study was able to demonstrate a protective effect of the tested compounds versus O_3-induced cell damage in human keratinocytes. Pre-treatment with the tested compounds significantly reduced the oxidative damage induced by O₃ exposure and this protective effect was correlated to the abolishment of NF-kB nuclear translocation, as well as activation of Nrf2 nuclear translocation activating the downstream defence enzymes involved in cellular detoxification process.

Resveratrol prevents cigarette smoke-induced keratinocytes damage

The plant polyphenol, resveratrol (Resv, 3,4,5-trihydroxystilbene), naturally occurring in a number of fruits and other food products, has been extensively studied over the last two decades for its beneficial properties. Recently, its possible topical use in ameliorating skin conditions has also been proposed; however, its role in preventing cigarette smoke (CS)-induced keratinocyte damage has not been investigated yet. Because of its peculiar location, cutaneous tissue is constantly exposed to several environmental stressors, such as CS. Many compounds presented in CS, have been shown to induce, directly or indirectly, cellular oxidative stress (OS) and inflammation via the production of ROS and lipid peroxidation compounds, among which 4HNE has been shown to be one of the most reactive. In this study, we have shown that resveratrol (at a dose of 10 μM) can decrease CS-induced ROS and carbonyl formation in human keratinocytes. In addition, pre-treatment with resveratrol prevented the induction of TRPA1 expression (mRNA and protein levels), a known receptor involved in cellular differentiation and inflammation, which has been recently shown to be activated by 4HNE. Finally, in keratinocytes, resveratrol could increase the expression of MsrA, enzyme involved in cell defence against oxidative protein damage. The present study further confirms the idea that the topical use of resveratrol can provide a good defence against CS-induced skin damage.

The loss of cellular junctions in epithelial lung cells induced by cigarette smoke is attenuated by corilagin

Cigarette smoke (CS) contains over 4700 compounds, many of which can affect cellular redox balance through free radicals production or through the modulation of antioxidant enzymes. The respiratory tract is one of the organs directly exposed to CS and it is known that CS can damage the integrity of lung epithelium by affecting cell junctions and increasing epithelium permeability. In this study, we have used a human lung epithelial cell line, Calu-3, to evaluate the effect of CS on lung epithelial cell junctions levels, with special focus on the expression of two proteins involved in intercellular communication: connexins (Cx) 40 and 43. CS exposure increased Cx40 gene expression but not of Cx43. CS also induced NFκB activation and the formation of 4HNE-Cxs adducts. Since corilagin, a natural polyphenol, is able to inhibit NFκB activation, we have determined whether corilagin could counteract the effect of CS on Cxs expression. Corilagin was able to diminish CS induced Cx40 gene expression, 4HNE-Cx40 adducts formation, and NFκB activation. The results of this study demonstrated that CS induced the loss of cellular junctions in lung epithelium, possibly as a consequence of Cx-4HNE adducts formation, and corilagin seems to be able to abolish these CS induced alterations.

Wound healing properties of hyaluronan derivatives bearing ferulate residues

The results obtained suggestHAFAgraft copolymers as possible future drugs for the therapeutic treatment of acute and chronic wounds.

Correction: Wound healing properties of hyaluronan derivatives bearing ferulate residues

Correction for ‘Wound healing properties of hyaluronan derivatives bearing ferulate residues’ by Giuseppe Valacchi et al., J. Mater. Chem. B, 2015, DOI: 10.1039/c5tb00661a.

Scavenger Receptor B1 oxidative post-translational modifications are responsible for its loss in Rett syndrome

The modulation of the HDL receptor scavenger receptor B1 (SRB1) was evaluated in skin fibroblasts isolated from Rett syndrome (RTT) patients, a rare neurodevelopmental disorder affecting almost exclusively females associated in up to 95% of cases to de novo loss-of-function mutations in the X-chromosome-linked gene encoding the methyl-CpG-binding protein 2 (MeCP2). Patients showed an altered plasma lipid profile, while their skin fibroblasts showed a dramatic reduction in SRB1 (immunogold, Western blot and immunohistochemistry). The decreased SRB1 levels were demonstrated to be the consequence of its binding with 4-hydroxy-2-nonenal (4HNE), a product of lipid peroxidation, and its increased ubiquitination. Therefore the loss of SRB1 in RTT cells is a consequence of the chronic oxidative stress status present in RTT. In addition RTT fibroblast presented high intracellular levels of H2O2 and 4HNE protein adducts. This finding was correlated with the constitutive activation of NADPH oxidase (NOX) and was reverted by DPI (NOX inhibitor) or Desferal (Iron chelator) pre-treatment. To confirm the alteration of status redox in RTT cells, the activity of several enzymes involved in protecting the cell from OS was also evaluated. Glutathione peroxidase (GPx), Supeoxide dismutase and Glucose-6-phosphate dehydrogenase (G6PDH) activity were decreased respect to control. These data paralleled with a constitutive activation of NRF2 and elevated gene expression of Heme oxigenase-1 (HO-1) and NAD(P)H dehydrogenase quinone 1 (NQO-1). Of note, when NRF2 pathway was stimulated via exogenous oxidants, RTT fibroblast did not respond as the control cells.

Cholesterol metabolism is altered in Rett syndrome: a study on plasma and primary cultured fibroblasts derived from patients

Rett (RTT) syndrome is a severe neurological disorder that affects almost exclusively females. Several detectable mutations in the X-linked methyl-CpG-binding protein 2 gene (MECP2) are responsible for the onset of the disease. MeCP2 is a key transcription regulator involved in gene silencing via methylation-dependent remodeling of chromatin. Recent data highlight that lipid metabolism is perturbed in brains and livers of MECP2-null male mice. In addition, altered plasma lipid profile in RTT patients has been observed. Thus, the aim of the work is to investigate the protein network involved in cholesterol homeostasis maintenance on freshly isolated fibroblasts and plasma from both RTT and healthy donors. To this end, protein expression of 3-hydroxy-3methyl glutaryl Coenzyme A reductase (HMGR), sterol regulatory element binding proteins (SREBPs), low density lipoprotein receptor (LDLr) and scavenger receptor B-1 (SRB-1) was assessed in cultured skin fibroblasts from unaffected individuals and RTT patients. In addition, lipid profile and the abundance of proprotein convertase subtilisin/kexin type 9 (PCSK9) were analyzed on plasma samples. The obtained results demonstrate that the main proteins belonging to cholesterol regulatory network are altered in RTT female patients, providing the proof of principle that cholesterol metabolism may be taken into account as a new target for the treatment of specific features of RTT pathology.

Comparative effects between electronic and cigarette smoke in human keratinocytes and epithelial lung cells

Information about the harmful effects of vaping is sparse and inconsistent, therefore, since the use of electronic cigarettes (e-CIGs) has become increasingly popular as a tool to limit tobacco smoking, it is urgent to establish the toxicity of the commercial e-CIGs. Skin (HaCaT) and lung (A549) cells, the main targets of cigarette smoke (CS), were exposed to e-CIG vapor and CS using an in vitro system. The cytotoxic effect of the exposure was analyzed in both cell types by ultrastructural morphology, Trypan Blue exclusion test and LDH assay. In addition, pro-inflammatory cytokines were measured by the Bio-Plex assay. The cytotoxic components of e-CIG were restrained to the flavoring compound and, to a lesser extent, to nicotine although their effects were less harmful to that of CS. Humectants alone exhibited no cytotoxicity but induced the release of cytokines and pro-inflammatory mediators. Based on our results, we can state that exposure to e-CIG vapors results in far less toxic than exposure to CS. In fact, besides the deleterious effect of flavor and nicotine, even the humectants alone are able to evocate cytokines release. This study will hopefully promote the development of safer e-CIGs to help people quit smoking.

The Magic Velvet Bean of Mucuna pruriens

Mucuna pruriens (Fabaceae) is an established herbal drug used for the management of male infertility, nervous disorders, and also as an aphrodisiac. It has been shown that its seeds are potentially of substantial medicinal importance. The ancient Indian medical system, Ayurveda, traditionally used M. pruriens, even to treat such things as Parkinson's disease. M. pruriens has been shown to have anti-parkinson and neuroprotective effects, which may be related to its anti-oxidant activity. In addition, anti-oxidant activity of M. pruriens has been also demonstrated in vitro by its ability to scavenge DPPH radicals and reactive oxygen species. In this review the medicinal properties of M. pruriens are summarized, taking in consideration the studies that have used the seeds extracts and the leaves extracts.

Resveratrol protects SR-B1 levels in keratinocytes exposed to cigarette smoke

Cigarette smoking (CS) has been strongly linked to several health conditions including heart disease, lung cancer, and other respiratory and circulatory ailments. Deleterious effects of cigarette smoking on skin have also been well documented, but unlike effects on other organs, damage does not depend upon inhalation. The upper layer of the skin, the stratum corneum (rich in cholesterol fatty acids and ceramide), is very susceptible to damage induced by exposure to environmental stressors that can modify its lipid composition and thereby affect its function of protecting skin from dehydration. Scavenger receptor B1 (SR-B1) is involved in the uptake of cholesterol in several tissues including skin. We previously demonstrated that CS exposure induces formation of aldehyde (HNE) adducts that decrease SR-B1 expression. As topical resveratrol, a well-known polyphenolic stilbene, has been demonstrated to show benefits against skin disorders, we investigated its possible role as a protective agent against CS-induced reduction of SR-B1 expression in cutaneous tissue. In this study, we demonstrate that resveratrol at doses ranging from 0.5 to 10 μM is not toxic and is able to increase SR-B1 protein levels in a dose-dependent manner in human keratinocytes. Moreover, when the cells that were pretreated with various doses of resveratrol were exposed to CS, the loss of SR-B1 was prevented in a dose-dependent manner. In addition, in keratinocytes, resveratrol was also able to prevent an increase in HNE-protein adducts induced by CS. In particular resveratrol was able to prevent HNE-SR-B1 adduct formation. Thus, resveratrol seems to be a natural compound that could provide skin with a defense against exogenous stressors by protecting the essential cholesterol receptor, SR-B1.

Beta-actin deficiency with oxidative posttranslational modifications in Rett syndrome erythrocytes: insights into an altered cytoskeletal organization

Beta-actin, a critical player in cellular functions ranging from cell motility and the maintenance of cell shape to transcription regulation, was evaluated in the erythrocyte membranes from patients with typical Rett syndrome (RTT) and methyl CpG binding protein 2 (MECP2) gene mutations. RTT, affecting almost exclusively females with an average frequency of 1∶10,000 female live births, is considered the second commonest cause of severe cognitive impairment in the female gender. Evaluation of beta-actin was carried out in a comparative cohort study on red blood cells (RBCs), drawn from healthy control subjects and RTT patients using mass spectrometry-based quantitative analysis. We observed a decreased expression of the beta-actin isoforms (relative fold changes for spots 1, 2 and 3: −1.82±0.15, −2.15±0.06, and −2.59±0.48, respectively) in pathological RBCs. The results were validated by western blotting and immunofluorescence microscopy. In addition, beta-actin from RTT patients also showed a dramatic increase in oxidative posttranslational modifications (PTMs) as the result of its binding with the lipid peroxidation product 4-hydroxy-2-nonenal (4-HNE). Our findings demonstrate, for the first time, a beta-actin down-regulation and oxidative PTMs for RBCs of RTT patients, thus indicating an altered cytoskeletal organization.

Proteomic profiling and post-translational modifications in human keratinocytes treated with Mucuna pruriens leaf extract

ETHNOPHARMACOLOGICAL RELEVANCE

Mucuna pruriens (Mp) is a plant belonging to the Fabaceae family, with several medicinal properties among which its potential to treat diseases where reactive oxygen species (ROS) play an important role in the pathogeneses. The aim was to investigate the effects of Mp leaf methanolic extract (MPME) on human keratinocytes protein expression and its role in preventing proteins oxidation after oxidative stress (OS) exposure.

MATERIAL AND METHODS

The effects of MPME on HaCaT cells protein expression were evaluated treating cells with different concentrations of MPME, with glucose oxidase (GO, source of OS) and with MPME subsequently treated with GO. The protein patterns of treated HaCaT cells are analyzed by two-dimensional gel electrophoresis (2-DE) and compared with that of untreated HaCaT. Immunoblotting was then used to evaluate the role of MPME in preventing the 4-hydroxynonenal protein adducts (4-HNE PAs) formation (marker of OS).

RESULTS

Eighteen proteins, identified by mass spectrometry (LC-ESI-CID-MS/MS), were modulated distinctly by MPME in HaCaT. Overall, MPME counteract GO effect, reducing the GO-induced overexpression of several proteins involved in stress response (T-complex protein 1, Protein disulfide-isomerase A3, Protein DJ-1, and Stress-induced-phosphoprotein 1), in cell energy methabolism (Inorganic pyrophosphatase, Triosephosphate isomerase isoform 1, 2-phosphopyruvate-hydratase alpha-enolase, and Fructose-bisphosphate aldolase A isoform 1), in cytoskeletal organization (Cytokeratins 18, 9, 2, Cofilin-1, Annexin A2 and F-actin-capping protein subunit beta isoform 1) and in cell cycle progression (Eukaryotic translation initiation factor 5A-1 isoform B). In addition, MPME decreased the 4-HNE PAs levels, in particular on 2-phosphopyruvate-hydratase alpha-enolase and Cytokeratin 9.

CONCLUSIONS

Our findings show that MPME might be helpful in the treatment of OS-related skin diseases by preventing protein post-translational modifications (4-HNE PAs).

Hypoxia induces cell damage via oxidative stress in retinal epithelial cells

Retinal diseases (RD), including diabetic retinopathy, are among the most important eye diseases in industrialized countries. RD is characterized by abnormal angiogenesis associated with an increase in cell proliferation and apoptosis. Hypoxia could be one of the triggers of the pathogenic mechanism of this disease. A key regulatory component of the cell's hypoxia response system is hypoxia-inducible factor 1 alpha (HIF-1α). It has been demonstrated that the induction of HIF-1α expression can be also achieved in vitro by exposure with cobalt chloride (CoCl2), leading to an intracellular hypoxia-like state. In this study we have investigated the effects of CoCl2 on human retinal epithelium cells (hRPE), which are an integral part of the blood-retinal barrier, with the aim to determine the possible role of oxidative stress in chemical hypoxia-induced damage in retinal epithelial cells. Our data showed that CoCl2 treatment is able to induce HIF-1α expression, that parallels with the formation of reactive oxygen species (ROS) and the increase of lipid 8-isoprostanes and 4-hydroxynonenal (4-HNE) protein adducts levels. In addition we observed the activation of the redox-sensitive transcription factor nuclear factor-kappaB (NFkB) by CoCl2 which can explain the increased levels of vascular endothelial growth factor (VEGF). The increased number of dead cells seems to be related to an apoptotic process. Taken together these evidences suggest that oxidative stress induced by hypoxia might be involved in RD development through the stimulation of two key-events of RD such as neo-angiogenesis and apoptosis.

Accumulation of central fat correlates with an adverse oxidative balance in non-obese postmenopausal women

The aim of the present study was to investigate whether accumulation of central fat is correlated with systemic oxidative stress (OxS) in non-obese apparently healthy postmenopausal women. Serum parameters of OxS (hydroperoxides and non-enzymatic antioxidants) along with body fat distribution, as assessed by dual-energy-X-ray absorptiometry (DXA), were evaluated in 134 non-obese postmenopausal women. Multiple regression analysis showed that central (trunk) fat significantly correlated with both markers of OxS independently of confounding factors (i.e. BMI, smoking, age, hypertension, legs and arms fat mass). In specific, the standardized regression coefficient was positive for hydroperoxides (β = 0.324, p < 0.05) and negative for antioxidants (β = -0.495, p < 0.01) level. In conclusion, the current data showed that the increase in central fat is an independent predictor of OxS condition among non-obese women in postmenopausal status. The possible pro-oxidant effects of the excess in central adiposity might be more harmful among post- than among pre-menopausal women, due to the postulated ability of E2 to contrast oxidative challenge and the related diseases.

Ozonated oils as functional dermatological matrices: effects on the wound healing process using SKH1 mice

Wound tissue repair is a complex and dynamic process of restoring cellular structures and tissue layers. Improvement of this process is crucial for several pathologies characterized by chronic delayed wound closure such as diabetes, and the investigation of new approaches aimed to ameliorate the wound healing process is under continuous evolution. Recently, the usage of vegetable matrices in the form of ozonated oils has been proposed and several researchers have shown a positive effect in the wound, based on their bactericidal, antiviral, and antifungal properties. The present study was undertaken to compare the effect that different ozonated oils (olive, sesame and linseed) with the same level of ozonation have on wound healing rate in SKH1 mice. Several histological parameters and the level of key proteins such as VEGF and PCNA have been analyzed. Only treatment with ozonated sesame oil shows a faster wound closure in the first 7 days. This effect paralleled with the increased VEGF and PCNA levels, NFκB nuclear translocation and 4-HNE formation. The present study shows that not only the ozonation grade is of importance for the improvement of wound healing process but also the typical composition of the oil.

IL-1β induces GFAP expression in vitro and in vivo and protects neurons from traumatic injury-associated apoptosis in rat brain striatum via NFκB/Ca²⁺-calmodulin/ERK mitogen-activated protein kinase signaling pathway

Reactive astrogliosis, a feature of neuro-inflammation is induced by a number of endogenous mediators including cytokines. Despite interleukin-1 beta (IL-1β) stands out as the major inducer of this process, the underlying mechanism and its role on neuronal viability remain elusive. We investigated in human astrocytoma cells and the rat brain striatum, the role of the nuclear factor-kB (NF-kB) intracellular Ca(2+) concentration ([Ca(2+)]i) calmodulin (CaM) and extracellular regulated mitogen-activated protein kinases (ERK1/2) in IL-1β-induced expression of glial fibrillary acidic protein (GFAP) and neuronal apoptosis associated to a brain trauma. Cell data showed that IL-1β (1 ng/ml) increased NF-kB, pERK1/2 and GFAP expression. Nevertheless, further increase in IL-1β levels reversed progressively these responses. Preventing ERK1/2 activation with 1,4-diamino-2,3-dicyano-1,4-bis[2-aminophenylthiol]-butadiene antagonized IL-1β-induced GFAP expression while inhibiting selectively nuclear translocation of NF-kB with caffeic-acid phenethyl-ester down-regulated both ERK1/2 and GFAP expression induced by IL-1β. The GFAP response was also prevented by antagonizing selectively increase in [Ca(2+)]i, CaM activity or inducible nitric oxide synthase expression with respectively ryanodine plus 2-aminoethoxydiphenyl-borate, N-(6-aminohexyl)-5-chloro-1-naphthalensulfonamide hydrochloride and N-[(3-(aminomethyl)-phenyl]methyl]-ethanimidamide dihydrochloride. Data in vivo supported these findings and showed that GFAP expression induced by IL-1β (50 ng/ml) correlated with attenuated glial scar formation and reduced neuronal apoptosis. Our data identified the NF-kB/Ca(2+)-CaM/ERK signaling pathway as a novel in vivo key regulator of IL-1β-induced astrogliosis which may represent a potential target in neurodegeneration.

Antiproliferative effect of two novel COX-2 inhibitors on human keratinocytes

Selective COX-2 inhibitors (COXib) belonging to the class of diaryl heterocycles (e.g., celecoxib, rofecoxib, etc.), are devoid of the undesirable effects due to their capacity to inhibit selectively inducible (COX-2), responsible for inflammatory effects but not constitutive cyclooxygenase-1 (COX-1)(COX); responsible for cytoprotective effects on gastric mucosa. In addition, several reports have identified an increased risk of cardiovascular events associated with the use of COXib. We have developed a new series of anti-inflammatory agents (1,5-diarylpyrrole-3-alkoxyethyl esters and ethers). To evaluate the effect of two 1,5-diarylpyrrole-3-alkoxyethyl ethers, VA441 and VA428 (up to 100 μM), respectively, in comparison with two well known COXib, celecoxib and rofecoxib, on HaCaT cell (keratinocytes) proliferation and toxicity. Crucial molecules in cell cycle progression, i.e. NFκB and ERK as targets/mediators and cyclin D1 and p21 Cip1/Kip as final effectors were evaluated by Western blot, immunohystochemistry and q-PCR analysis. Both compounds, VA441 and VA428, showed a strong inhibition of cell proliferation, and did not exhibit cytotoxicity. The anti-proliferative effect was accompanied by a strong activation of ERK and induction of the cell cycle inhibitor p21. In addition, there was a clear inhibition of the transcription factor NF-κB and downregulation of cyclin D1, with enforced inhibition of the HaCaT cell cycle progression. These data suggest that compounds VA441 and VA428, along with their role in inhibiting COX-2 and inflammation, could have a possible therapeutic (topical and systemic) use against skin proliferative disorders, such as psoriasis.

Cutaneous responses to environmental stressors

Living organisms are continuously exposed to environmental pollutants. Because of its critical location, the skin is a major interface between the body and the environment and provides a biological barrier against an array of chemical and physical environmental pollutants. The skin can be defined as our first defense against the environment because of its constant exposure to oxidants, including ultraviolet (UV) radiation and other environmental pollutants such as diesel fuel exhaust, cigarette smoke (CS), halogenated hydrocarbons, heavy metals, and ozone (O₃). The exposure to environmental pro-oxidant agents leads to the formation of reactive oxygen species (ROS) and the generation of bioactive molecules that can damage skin cells. This short review provides an overview of the effects and mechanisms of action of CS, O₃, and UV on cutanous tissues.

Rottlerin exhibits antiangiogenic effects in vitro

Rottlerin, a natural product purified from Mallotus philippinensis, has a number of target molecules and biological effects. We recently found that Rottlerin caused growth arrest in MCF-7 breast cancer cells and human immortalized keratinocytes, through inhibition of NFκB and downregulation of cyclin D-1. To evaluate whether this effect could be generalized to primary cells, human microvascular endothelial cells were treated with Rottlerin. In this study, we demonstrated that Rottlerin prevents basal and TNFα-stimulated NFκB nuclear migration and DNA binding also in human microvascular endothelial cell, where NFκB inhibition was accompanied by the downregulation of NFκB target gene products, such as cyclin D-1 and endothelin-1, which are essential molecules for endothelial cell proliferation and survival. Rottlerin, indeed, inhibited human microvascular endothelial cells proliferation and tube formation on Matrigel. Rottlerin also increases cytoplasmic free calcium and nitric oxide levels and downregulates endothelin converting enzyme-1 expression, thus contributing to the drop in endothelin-1 and growth arrest. These results suggest that Rottlerin may prove useful in the development of therapeutic agents against angiogenesis.