Combined exposure to UV and PM affect skin oxinflammatory responses and it is prevented by antioxidant mix topical application: Evidences from clinical study

BACKGROUND

Exposure to environmental stressors like particulate matter (PM) and ultraviolet radiation (UV) induces cutaneous oxidative stress and inflammation and leads to skin barrier dysfunction and premature aging. Metals like iron or copper are abundant in PM and are known to contribute to reactive oxygen species (ROS) production.

AIMS

Although it has been suggested that topical antioxidant may be able to help in preventing and/or reducing outdoor skin damage, limited clinical evidence under real-life exposure conditions have been reported. The aim of the present study was to evaluate the ability of a topical serum containing 15% ascorbic acid, 0.5% ferulic acid, and 1% tocopherol (CF Mix) to prevent oxinflammatory skin damage and premature aging induced by PM + UV in a human clinical trial.

METHODS

A 4-day single-blinded, clinical study was conducted on the back of 15 females (18-40 years old). During the 4 consecutive days, the back test zones were treated daily with or without the CF Mix, followed by with/without 2 h of PM and 5 min of UV daily exposure.

RESULTS

Application of the CF Mix prevented PM + UV-induced skin barrier perturbation (Involucrin and Loricrin), lipid peroxidation (4HNE), inflammatory markers (COX2, NLRP1, and AhR), and MMP9 activation. In addition, CF Mix was able to prevent Type I Collagen loss.

CONCLUSION

This is the first human study confirming the multipollutants cutaneous damage and suggesting the utility of a daily antioxidant topical application to prevent pollution induced skin damage.

A proteomic approach to investigate the role of the MECP2 gene mutation in Rett syndrome redox regulatory pathways

Mutations in the X-linked methyl-CpG-binding 2 (MECP2) gene lead to Rett Syndrome (RTT; OMIM 312750), a devasting neurodevelopmental disorder. RTT clinical manifestations are complex and with different degrees of severity, going from autistic-like behavior to loss of acquired speech, motor skills and cardiac problems. Furthermore, the correlation between the type of MECP2 mutation and the clinical phenotype is still not fully understood. Contextually, different genotypes can differently affect the patient's phenotype and omics methodologies such as proteomics could be an important tool for a molecular characterization of genotype/phenotype correlation. The aim of our study was focused on evaluating RTT oxidative stress (OS) responses related to specific MECP2 gene mutations by using proteomics and bioinformatics approaches. Primary fibroblasts isolated from patients affected by R133C and R255× mutations were compared to healthy controls (HC). After clustering primary dermal fibroblasts based on their specific MECP2 mutations, fibroblast-derived protein samples were qualitative and quantitative analyzed, using a label free quantification (LFQ) analysis by mass spectrometry (MS), achieving a preliminary correlation for RTT genotype/phenotype. Among the identified proteins involved in redox regulation pathways, NAD(P)H:quinone acceptor oxidoreductase 1 (NQO1) was found to be absent in R255× cells, while it was present in R133C and in HC fibroblasts. Moreover, NQO1 aberrant gene regulation was also confirmed when cells were challenged with 100 μM hydrogen peroxide (H2O2). In conclusion, by employing a multidisciplinary approach encompassing proteomics and bioinformatics analyses, as well as molecular biology assays, the study uncovered phenotypic responses linked to specific MECP2 gene mutations. These findings contribute to a better understanding of the complexity of RTT molecular pathways, confirming the high heterogeneity among the patients.

Nutlin-3 Loaded Ethosomes and Transethosomes to Prevent UV-Associated Skin Damage

The skin's protective mechanisms, in some cases, are not able to counteract the destructive effects induced by UV radiations, resulting in dermatological diseases, as well as skin aging. Nutlin-3, a potent drug with antiproliferative activity in keratinocytes, can block UV-induced apoptosis by activation of p53. In the present investigation, ethosomes and transethosomes were designed as delivery systems for nutlin-3, with the aim to protect the skin against UV damage. Vesicle size distribution was evaluated by photon correlation spectroscopy and morphology was investigated by cryogenic transmission electron microscopy, while nutlin-3 entrapment capacity was evaluated by ultrafiltration and HPLC. The in vitro diffusion kinetic of nutlin-3 from ethosomes and transethosomes was studied by Franz cell. Moreover, the efficiency of ethosomes and transethosomes in delivering nutlin-3 and its protective role were evaluated in ex vivo skin explants exposed to UV radiations. The results indicate that ethosomes and transethosomes efficaciously entrapped nutlin-3 (0.3% w/w). The ethosome vesicles were spherical and oligolamellar, with a 224 nm mean diameter, while in transethosome the presence of polysorbate 80 resulted in unilamellar vesicles with a 146 nm mean diameter. The fastest nutlin-3 kinetic was detected in the case of transethosomes, with permeability coefficients 7.4-fold higher, with respect to ethosomes and diffusion values 250-fold higher, with respect to the drug in solution. Ex vivo data suggest a better efficacy of transethosomes to promote nutlin-3 delivery within the skin, with respect to ethosomes. Indeed, nutlin-3 loaded transethosomes could prevent UV effect on cutaneous metalloproteinase activation and cell proliferative response.

Vitamin C compounds mixture prevents skin barrier alterations and inflammatory responses upon real life multi pollutant exposure

Cutaneous tissues is among the main target of outdoor stressors such as ozone (O3 ), particulate matter (PM), and ultraviolet radiation (UV) all involved in inducing extrinsic skin aging. Only a few reports have studied the multipollutant interaction and its effect on skin damage. In the present work, we intended to evaluate the ability of pollutants such as O3 and PM to further aggravate cutaneous UV damage. In addition, the preventive properties of a cosmeceutical formulation mixture (AOX mix) containing 15% vitamin C (L-ascorbic acid), 1% vitamin E (α-tocopherol) and 0.5% ferulic acid was also investigated. Skin explants obtained from three different subjects were exposed to 200 mJ UV light, 0.25 ppm O3 for 2 h, and 30 min of diesel engine exhaust (DEE), alone or in combination for 4 days (time point D1 and D4). The results showed a clear additive effect of O3 and DEE in combination with UV in terms of keratin 10, Desmocollin and Claudin loss. In addition, the multipollutant exposure significantly induced the inflammatory response measured as NLRP1/ASC co-localization suggesting the activation of the inflammasome machinery. Finally, the loss of Aquaporin3 was also affected by the combined outdoor stressors. Furthermore, daily topical pre-treatment with the AOX Mix significantly prevented the cutaneous changes induced by the multipollutants. In conclusion, this study is among the first to investigate the combined effects of three of the most harmful outdoor stressors on human skin and confirms that daily topical of an antioxidant application may prevent pollution-induced skin damage.

Comparison of Pollutant Effects on Cutaneous Inflammasomes Activation

The skin is the outermost layer of the body and, therefore, is exposed to a variety of stressors, such as environmental pollutants, known to cause oxinflammatory reactions involved in the exacerbation of several skin conditions. Today, inflammasomes are recognized as important modulators of the cutaneous inflammatory status in response to air pollutants and ultraviolet (UV) light exposure. In this study, human skin explants were exposed to the best-recognized air pollutants, such as microplastics (MP), cigarette smoke (CS), diesel engine exhaust (DEE), ozone (O3), and UV, for 1 or 4 days, to explore how each pollutant can differently modulate markers of cutaneous oxinflammation. Exposure to environmental pollutants caused an altered oxidative stress response, accompanied by increased DNA damage and signs of premature skin aging. The effect of specific pollutants being able to exert different inflammasomes pathways (NLRP1, NLRP3, NLRP6, and NLRC4) was also investigated in terms of scaffold formation and cell pyroptosis. Among all environmental pollutants, O3, MP, and UV represented the main pollutants affecting cutaneous redox homeostasis; of note, the NLRP1 and NLRP6 inflammasomes were the main ones modulated by these outdoor stressors, suggesting their role as possible molecular targets in preventing skin disorders and the inflammaging events associated with environmental pollutant exposure.

A Plant-Based Dietary Supplement Improves Measures of Metabolic Detoxification and the Quality of Life: A Phase II Multicenter Randomized, Blinded, Placebo-Controlled Clinical Trial

Background

Persistent accumulation and hindered clearance of toxins from tissues over time may promote the development and exacerbation of several diseases. Hepatic metabolic detoxification is a key physiological process responsible for the clearance of toxic substances from the body. A healthy diet with nutritional dietary supplementation may support metabolic detoxification and help mitigate the negative effects of toxin burden.

Methods

A multicenter, randomized, single-blind, controlled trial was conducted to test the effects of a dietary detoxification product (detox; n = 20) versus an active dietary control product (active control; n = 20) on selected biomarkers of metabolic detoxification, general health, and well-being following 28 days of dietary supplementation. Study participants displayed multiple symptoms commonly associated with elevated toxin burden, but otherwise healthy.

Results

The detox group displayed significantly decreased levels of red blood cell total toxic metals, decreased urine total porphyrins, and decreased urine mutagenicity potency compared with baseline. Both the detox and active control groups showed improvements in the symptoms attributed to elevated toxin burden. Fatigue and sleep disruption scores were significantly reduced in the detox group compared with baseline. No significant differences in anthropometric measures and vital signs, and no adverse events or side effects were detected in either group over the study period.

Conclusions

This study demonstrates the benefit of nutritional intervention for supporting metabolic detoxification, evidenced by significant changes in multiple detoxification biomarkers and improvement in questionnaire scores related to quality of life, general health, and well-being.

Redox Regulation of Nucleotide-Binding and Oligomerization Domain-Like Receptors Inflammasome

Significance: Inflammasomes are multimeric complexes that, as part of the innate immune response, sense a wide range of pathogenic and sterile stimuli. They consist of three components, namely a sensor protein, an adaptor, and procaspase-1, which once activated result in secretion of proinflammatory interleukin (IL)-1β and IL-18 and, eventually, in a gasdermin D-dependent lytic cell death called pyroptosis. Recent Advances: Since their discovery 20 years ago, the molecular mechanisms underlying the regulation of inflammasomes have been extensively studied. Oxidative stress appears as a major contributor to modulate inflammasomes, especially NLRP3 as well as NLRP1, NLRP6, and NLRC4. Growing evidence supports the idea that the positive feedback between redox imbalance and inflammasome-driven inflammation fuels an OxInflammatory state in a variety of human pathologies. Critical Issues: The current knowledge about the redox signaling pathways involved in inflammasomes activation and functions are here highlighted. In addition, we discuss the role of this complex molecular network interaction in the onset and progression of pathological conditions including neurological and metabolic diseases as well as skin disorders, also with an insight on COVID-19-related pathology. Finally, the therapeutic strategies able to mitigate the redox-mediated inflammasome activation with synthetic and natural compounds as well as by acting on inflammasome-related post-translational modifications and microRNAs are also addressed. Future Directions: Further investigations leading to a deeper understanding of the reciprocal interaction between inflammasomes and reactive oxygen species will help identify other molecular targets for modulating their hyperactivated state, and to design novel therapeutics for chronic OxInflammatory conditions. Antioxid. Redox Signal. 39, 744-770.

Ox-inflammasome involvement in neuroinflammation

Neuroinflammation plays a crucial role in the onset and the progression of several neuropathologies, from neurodegenerative disorders to migraine, from Rett syndrome to post-COVID 19 neurological manifestations. Inflammasomes are cytosolic multiprotein complexes of the innate immune system that fuel inflammation. They have been under study for the last twenty years and more recently their involvement in neuro-related conditions has been of great interest as possible therapeutic target. The role of oxidative stress in inflammasome activation has been described, however the exact way of action of specific endogenous and exogenous oxidants needs to be better clarified. In this review, we provide the current knowledge on the involvement of inflammasome in the main neuropathologies, emphasizing the importance to further clarify the role of oxidative stress in its activation including the role of mitochondria in inflammasome-induced neuroinflammation.

Tension as a key factor in skin responses to pollution

Being the more apparent organ exposed to the outdoor stressors, the effect of pollution on the skin has been widely studied in the last few decades. Although UV light is known as the most aggressive stressor to which our cutaneous tissue is daily exposed, other components of the tropospheric pollution have also shown to affect skin health and functionality. Among them, ozone has been proven to be one of the most toxic due to its high reactivity with the epidermal lipids. Studying the cutaneous effect of pollution in a laboratory setting presents challenges, therefore it becomes critical to employ appropriate and tailored models that aim to answer specific questions. Several skin models are available nowadays: in vitro models (2D cell lines and 3D cutaneous tissues), ex vivo skin explants and in vivo approaches (animals and humans). Although in the last 20 years researchers developed skin models that closely resemble human skin (3D cutaneous tissues), ex vivo skin explants still remain one of the best models to study cutaneous responses. Unfortunately, one important cutaneous property that is not present in the traditional ex vivo human skin explants is the physiological tension, which has been shown to be a cardinal player in skin structure, homeostasis, functional properties and responses to external stimuli. For this reason, in this study, to confirm and further comprehend the harmful mechanism of ozone exposure on the integumentary system, we have performed experiments using the state of art in cutaneous models: the innovative TenSkin™ model in which ex vivo human skin explants are cultured under physiologically relevant tension during the whole experimental procedure. Specifically, we were interested in corroborating previous findings showing that ozone exposure modulates the expression of cutaneous antimicrobial peptides (AMPs). The present work demonstrates that cutaneous exposure to ozone induces AMPs gene and protein levels (CAMP/LL-37, hBD2, hBD3) and that the presence of tension can further modulate their expression. In addition, different responses between tension and non-tension cultured skin were also observed during the evaluation of OxInflammatory markers [cyclooxygenase-2 (COX2), aryl hydrocarbon receptor (AhR), matrix-metallo-proteinase 9 (MMP9) and 4-hydroxy-nonenal (4HNE)]. This current study supports our previous findings confirming the ability of pollution to induce the cutaneous expression of AMPs via redox signaling and corroborates the principle that skin explants are a good and reliable model to study skin responses even though it underlines the need to holistically consider the role of skin tension before extrapolating the data to real life.

Development of Spray Dried Spirulina Protein-Berry Pomace Polyphenol Particles to Attenuate Pollution-Induced Skin Damage: A Convergent Food-Beauty Approach

Spray drying (SD) microencapsulation of phytochemicals from berry pomaces with Spirulina protein (SP) was incorporated into a cosmeceutical topical formulation to mitigate pollution skin damage. Initially, microparticles produced with SP and polyphenols recovered from fruit pomaces (elderberry SP-EB and muscadine grape SP-MG) were characterized regarding physicochemical and phytochemical content (polyphenol load, carotenoid and phycocyanin contents and antioxidant activity). SP had low total phenolic content (7.43 ± 0.23 mg GAE/g DW), but complexation with elderberry or muscadine grape pomaces polyphenols led to a substantial increase (27.63 ± 1.15 SP-EB and 111.0 ± 2.6 mg GAE/g DW SP-MG). SP-MG particles had higher anthocyanin (26.87 ± 1.25 mg/g) and proanthocyanidin (9.02 ± 0.74 mg/g) contents compared to SP-EB particles. SP-MG were prioritized to prepare a topical gel to attenuate skin oxinflammatory markers and prevent skin barrier disruption using ex vivo human biopsies exposed to diesel engine exhaust (DEE). The immunofluorescence results showed increased oxidative protein damage and inflammation associated with impaired skin barrier function after DEE exposure while topical application of gel formulated with SP-MG mitigated these effects. Overall, this study demonstrated that protein-polyphenol complexation is a synergistic strategy to stabilize and deliver residual fruit/algae phytoactives into cosmeceutical products for skin health applications.

Blueberry Supplementation and Skin Health

Environmental stressors such as air pollutants, ozone, and UV radiation are among the most noxious outdoor stressors affecting human skin and leading to premature skin aging. To prevent the extrinsic aging, the skin is equipped with an effective defensive system. However, cutaneous defense mechanisms can be overwhelmed through chronic exposure to environmental pollutants. Recent studies have suggested that the topical usage of natural compounds, such as blueberries, could be a good strategy to prevent skin damage from the environment. Indeed, blueberries contain bioactive compounds found to induce an active skin response against the environmental noxious effects. In this review, results from recent studies on this topic are discussed in order to build the argument for blueberries to possibly be an effective agent for skin health. In addition, we hope to highlight the need for further research to elucidate the mechanisms behind the use of both topical application and dietary supplementation with blueberries to bolster cutaneous systems and defensive mechanisms.

The role of potassium current in the pulmonary response to environmental oxidative stress

Exposure of human lung epithelial cells (A549 cell line) to the oxidant pollutant ozone (O₃) alters cell membrane currents inducing its decrease, when the cell undergoes to a voltage-clamp protocol ranging from -90 to +70mV. The membrane potential of these cells is mainly maintained by the interplay of potassium and chloride currents. Our previous studies indicated the ability of O₃ to activate ORCC (Outward Rectifier Chloride Channel) and consequently increases the chloride current. In this paper our aim was to understand the response of potassium current to oxidative stress challenge and to identify the kind potassium channel involved in O₃ induced current changes. After measuring the total membrane current using an intracellular solution with or without potassium ions, we obtained the contribution of potassium to the overall membrane current in control condition by a mathematical approach. Repeating these experiments after O₃ treatment we observed a significant decrease of I_potassium. Treatment of the cells with Iberiotoxin (IbTx), a specific inhibitor of BK channel, we were able to verify the presence and the functionality of BK channels. In addition, the administration of 4-Aminopyridine (an inhibitor of voltage dependent K channels but not BK channels) and Tetraethylammonium (TEA) before and after O₃ treatment we observed the formation of BK oxidative post-translation modifications. Our data suggest that O₃ is able to inhibit potassium current by targeting BK channel. Further studies are needed to better clarify the role of this BK channel and its interplay with the other membrane channels under oxidative stress conditions. These findings can contribute to identify the biomolecular pathway induced by O₃ allowing a possible pharmacological intervention against oxidative stress damage in lung tissue.

Evaluation of Anti-Oxinflammatory and ACE-Inhibitory Properties of Protein Hydrolysates Obtained from Edible Non-Mulberry Silkworm Pupae (Antheraea assama and Philosomia ricinii)

Food-derived bioactive peptides (BAPs) obtained from edible insect-protein hold multiple activities promising the potential to target complex pathological mechanisms responsible for chronic health conditions such as hypertension development. In this study, enzymatic protein hydrolysates from non-mulberry edible silkworm Antheraea assama (Muga) and Philosomia ricini (Eri) pupae, specifically Alcalase (A. assama) and Papain (P. ricini) hydrolysates obtained after 60 and 240 min, exhibited the highest ACE-inhibitory and antioxidant properties. The hydrolysates' fractions (<3, 3-10 and >10 kDa), specifically Alc_M60min_F3 (≤3 kDa) and Pap_E240min_F3 (≤3 kDa), showed the highest antioxidant and ACE-inhibitory activities, respectively. Further RP-HPLC purified sub-fractions F4 and F6 showed the highest ACE inhibition as well as potent anti-oxinflammatory activities in lipopolysaccharide (LPS)-treated endothelial cells. Indeed, F4 and F6 ACE-inhibitory peptide fractions were effective in preventing p65 nuclear translocation after 3 h of LPS stimulation along with the inhibition of p38 MAPK phosphorylation in HUVEC cells. In addition, pretreatment with F4 and F6 ACE-inhibitory peptide fractions significantly prevented the LPS-induced upregulation of COX-2 expression and IL-1β secretion, while the expression of NRF2 (nuclear factor erythroid 2-related factor 2)-regulated enzymes such as HO-1 and NQO1 was induced by both peptide fractions. The derived peptides from edible pupae protein hydrolysates have potentialities to be explored as nutritional approaches against hypertension and related cardiovascular diseases.

Astaxanthin supplementation counters exercise-induced decreases in immune-related plasma proteins

Objectives

Astaxanthin is a dark red keto-carotenoid found in aquatic animals such as salmon and shrimp, and algae (Haematococcus pluvialis). Astaxanthin has a unique molecular structure that may facilitate anti-oxidative, immunomodulatory, and anti-inflammatory effects during physiological stress. The primary objective of this study was to examine the efficacy of 4-week ingestion of astaxanthin in moderating exercise-induced inflammation and immune dysfunction using a multi-omics approach.

Methods

This study employed a randomized, double blind, placebo controlled, crossover design with two 4-week supplementation periods and a 2-week washout period. Study participants were randomized to astaxanthin and placebo trials, with supplements ingested daily for 4 weeks prior to running 2.25 h at close to 70%VO_2max (including 30 min of 10% downhill running). After the washout period, participants repeated all procedures using the counterbalanced supplement. The astaxanthin capsule contained 8 mg of algae astaxanthin. Six blood samples were collected before and after supplementation (overnight fasted state), immediately post-exercise, and at 1.5, 3, and 24 h-post-exercise. Plasma aliquots were assayed using untargeted proteomics, and targeted oxylipin and cytokine panels.

Results

The 2.25 h running bout induced significant muscle soreness, muscle damage, and inflammation. Astaxanthin supplementation had no effect on exercise-induced muscle soreness, muscle damage, and increases in six plasma cytokines and 42 oxylipins. Notably, astaxanthin supplementation countered exercise-induced decreases in 82 plasma proteins (during 24 h recovery). Biological process analysis revealed that most of these proteins were involved in immune-related functions such as defense responses, complement activation, and humoral immune system responses. Twenty plasma immunoglobulins were identified that differed significantly between the astaxanthin and placebo trials. Plasma levels of IgM decreased significantly post-exercise but recovered after the 24 h post-exercise recovery period in the astaxanthin but not the placebo trial.

Discussion

These data support that 4-week astaxanthin versus placebo supplementation did not counter exercise-induced increases in plasma cytokines and oxylipins but was linked to normalization of post-exercise plasma levels of numerous immune-related proteins including immunoglobulins within 24 h. Short-term astaxanthin supplementation (8 mg/day during a 4-week period) provided immune support for runners engaging in a vigorous 2.25 h running bout and uniquely countered decreases in plasma immunoglobulin levels.

Ubiquitination as a key regulatory mechanism for O3-induced cutaneous redox inflammasome activation

NLRP1 is one of the major inflammasomes modulating the cutaneous inflammatory responses and therefore linked to a variety of cutaneous conditions. Although NLRP1 has been the first inflammasome to be discovered, only in the past years a significant progress was achieved in understanding the molecular mechanism and the stimuli behind its activation. In the past decades a crescent number of studies have highlighted the role of air pollutants as Particulate Matter (PM), Cigarette Smoke (CS) and Ozone (O₃) as trigger stimuli for inflammasomes activation, especially via Reactive Oxygen Species (ROS) mediators. However, whether NLRP1 can be modulated by air pollutants via oxidative stress and the mechanism behind its activation is still poorly understood. Here we report for the first time that O₃, one of the most toxic pollutants, activates the NLRP1 inflammasome in human keratinocytes via oxidative stress mediators as hydrogen peroxide (H₂O₂) and 4-hydroxy-nonenal (4HNE). Our data suggest that NLRP1 represents a target protein for 4HNE adduction that possibly leads to its proteasomal degradation and activation via the possible involvement of E3 ubiquitin ligase UBR2. Of note, Catalase (Cat) treatment prevented inflammasome assemble and inflammatory cytokines release as well as NLRP1 ubiquitination in human keratinocytes upon O₃ exposure. The present work is a mechanistic study that follows our previous work where we have showed the ability of O₃ to induce cutaneous inflammasome activation in humans exposed to this pollutant. In conclusion, our results suggest that O₃ triggers the cutaneous NLRP1 inflammasome activation by ubiquitination and redox mechanism.

Oxidative-Stress-Sensitive microRNAs in UV-Promoted Development of Melanoma

Simple Summary

Exposure to ultraviolet (UV) rays from the sun is one of the most important modifiable risk factors for skin cancer. Melanoma is the most life-threatening type of skin cancer. UV-induced DNA damage and oxidative stress represent two main mechanisms that, directly and indirectly, contribute to melanomagenesis. In addition, an interplay of abnormally expressed microRNAs (miRNAs) and redox imbalance is a hallmark in several cancers, including melanoma. UV radiation can be the central hub between these two cellular aberrations, as it is able to stimulate both. Here, to gain new mechanistic insights into melanomagenesis and identify new therapeutic targets for the prevention and treatment of melanoma, we report current evidence suggesting a complex interaction between UV-promoted deregulation of redox-sensitive miRNAs and known signal-transduction pathways underlying malignant transformation of melanocytes to melanoma.

Abstract

Melanoma is the most aggressive and life-threatening form of skin cancer. Key molecular events underlying the melanocytic transformation into malignant melanoma mainly involve gene mutations in which exposure to ultraviolet (UV) radiation plays a prominent role. However, several aspects of UV-induced melanomagenesis remain to be explored. Interestingly, redox-mediated signaling and perturbed microRNA (miRNA) profiles appear to be interconnected contributing factors able to act synergistically in melanoma initiation and progression. Since UV radiation can promote both redox imbalance and miRNA dysregulation, a harmful crosstalk between these two key cellular networks, with UV as central hub among them, is likely to occur in skin tissue. Therefore, decoding the complex circuits that orchestrate the interaction of UV exposure, oxidative stress, and dysregulated miRNA profiling can provide a deep understanding of the molecular basis of the melanomagenesis process. Furthermore, these mechanistic insights into the reciprocal regulation between these systems could have relevant implications for future therapeutic approaches aimed at counteracting UV-induced redox and miRNome imbalances for the prevention and treatment of malignant melanoma. In this review, we illustrate current information on the intricate connection between UV-induced dysregulation of redox-sensitive miRNAs and well-known signaling pathways involved in the malignant transformation of normal melanocytes to malignant melanoma.

The constitutive activation of TLR4-IRAK1- NFκB axis is involved in the early NLRP3 inflammasome response in peripheral blood mononuclear cells of Rett syndrome patients

Rett syndrome (RTT), a devastating neurodevelopmental disorder, is caused in 95% of the cases by mutations in the X-chromosome-localized MECP2 gene. To date, RTT is considered a broad-spectrum disease, due to multisystem disturbances affecting patients, associated with mitochondrial dysfunctions, subclinical inflammation and an overall OxInflammatory status. Inflammasomes are multi-protein complexes crucially involved in innate immune responses against pathogens and oxidative stress mediators. The assembly of NLRP3:ASC inflammasome lead to pro-caspase 1 activation, maturation of interleukins (IL)-1β and 18 and proteolytic cleavage of Gasdermin D leading eventually to pyroptosis and systemic inflammation. The possible de-regulation of this system, in parallel with upstream nuclear factor (NF)-κB p65 pathway, were analyzed in peripheral blood mononuclear cells (PBMCs) and plasma isolated from RTT patients and matching controls. RTT PBMCs showed a constitutive activation of the axis TLR4 (Toll-like receptor 4)-IRAK1 (interleukin-1 receptor associated kinase 1)-NF-κB p65, together with augmented ROS generation and enhanced IL-18 mRNA levels and NLRP3:ASC co-localization. The deregulation of inflammasome components was even found in THP-1 cells silenced for MECP2 and importantly, in plasma compartment of RTT subjects, from the earliest stages of the pathology or in correlation with the severity of MeCP2 mutations. Taken together, these data provide new insights into the mechanisms involved in RTT sub-clinical inflammatory status present in RTT patients, thus helping to reveal new targets for future therapeutic approaches.

Gastrointestinal tissue as a "new" target of pollution exposure

Airborne pollution has become a leading cause of global death in industrialized cities and the exposure to environmental pollutants has been demonstrated to have adverse effects on human health. Among the pollutants, particulate matter (PM) is one of the most toxic and although its exposure has been more commonly correlated with respiratory diseases, gastrointestinal (GI) complications have also been reported as a consequence to PM exposure. Due to its composition, PM is able to exert on intestinal mucosa both direct damaging effects, (by reaching it either via direct ingestion of contaminated food and water or indirect inhalation and consequent macrophagic mucociliary clearance) and indirect ones via generation of systemic inflammation. The relationship between respiratory and GI conditions is well described by the lung-gut axis and more recently, has become even clearer during coronavirus disease 2019 (COVID-19) pandemic, when respiratory symptoms were associated with gastrointestinal conditions. This review aims at pointing out the mechanisms and the models used to evaluate PM induced GI tract damage.

Novel Spray Dried Algae-Rosemary Particles Attenuate Pollution-Induced Skin Damage

The present study investigated the effect of spray-dried algae-rosemary particles against pollution-induced damage using ex-vivo human biopsies exposed to diesel engine exhaust (DEE). For this, the complexation of hydroalcoholic rosemary extract with Chlorella (RCH) and Spirulina (RSP) protein powders was conducted. The process efficiency and concentration of rosmarinic acid (RA), carnosic acid (CA), and carnosol (CR) phenolic compounds of both products were compared. The RSP spray-dried production was more efficient, and RSP particles presented higher CR and CA and similar RA concentrations. Therefore, spray-dried RSP particles were prioritized for the preparation of a gel formulation that was investigated for its ability to mitigate pollution-induced skin oxinflammatory responses. Taken altogether, our ex-vivo data clearly demonstrated the ability of RSP gel to prevent an oxinflammatory phenomenon in cutaneous tissue by decreasing the levels of 4-hydroxynonenal protein adducts (4HNE-PA) and active matrix metalloproteinase-9 (MMP-9) as well as by limiting the loss of filaggrin induced by DEE exposure. Our results suggest that the topical application of spirulina-rosemary gel is a good approach to prevent pollution-induced skin aging/damage.

Altered Bone Status in Rett Syndrome

Rett syndrome (RTT) is a monogenic neurodevelopmental disorder primarily caused by mutations in X-linked MECP2 gene, encoding for methyl-CpG binding protein 2 (MeCP2), a multifaceted modulator of gene expression and chromatin organization. Based on the type of mutation, RTT patients exhibit a broad spectrum of clinical phenotypes with various degrees of severity. In addition, as a complex multisystem disease, RTT shows several clinical manifestations ranging from neurological to non-neurological symptoms. The most common non-neurological comorbidities include, among others, orthopedic complications, mainly scoliosis but also early osteopenia/osteoporosis and a high frequency of fractures. A characteristic low bone mineral density dependent on a slow rate of bone formation due to dysfunctional osteoblast activity rather than an increase in bone resorption is at the root of these complications. Evidence from human and animal studies supports the idea that MECP2 mutation could be associated with altered epigenetic regulation of bone-related factors and signaling pathways, including SFRP4/WNT/β-catenin axis and RANKL/RANK/OPG system. More research is needed to better understand the role of MeCP2 in bone homeostasis. Indeed, uncovering the molecular mechanisms underlying RTT bone problems could reveal new potential pharmacological targets for the treatment of these complications that adversely affect the quality of life of RTT patients for whom the only therapeutic approaches currently available include bisphosphonates, dietary supplements, and physical activity.

Selective Fatty Acid Amide Hydrolase Inhibitors as Potential Novel Antiepileptic Agents

Temporal lobe epilepsy is the most common form of epilepsy, and current antiepileptic drugs are ineffective in many patients. The endocannabinoid system has been associated with an on-demand protective response to seizures. Blocking endocannabinoid catabolism would elicit antiepileptic effects, devoid of psychotropic effects. We herein report the discovery of selective anandamide catabolic enzyme fatty acid amide hydrolase (FAAH) inhibitors with promising antiepileptic efficacy, starting from a further investigation of our prototypical inhibitor 2a. When tested in two rodent models of epilepsy, 2a reduced the severity of the pilocarpine-induced status epilepticus and the elongation of the hippocampal maximal dentate activation. Notably, 2a did not affect hippocampal dentate gyrus long-term synaptic plasticity. These data prompted our further endeavor aiming at discovering new antiepileptic agents, developing a new set of FAAH inhibitors (3a-m). Biological studies highlighted 3h and 3m as the best performing analogues to be further investigated. In cell-based studies, using a neuroblastoma cell line, 3h and 3m could reduce the oxinflammation state by decreasing DNA-binding activity of NF-kB p65, devoid of cytotoxic effect. Unwanted cardiac effects were excluded for 3h (Langendorff perfused rat heart). Finally, the new analogue 3h reduced the severity of the pilocarpine-induced status epilepticus as observed for 2a.

Incidental pancreatic cystic lesions: comparison between CT with model-based algorithm and MRI

INTRODUCTION

The present study aims to compare low-kV CT reconstructed with MBIR technique with MRI in detecting high-risk stigmata and worrisome features in patients with pancreatic cystic lesions.

METHODS

We retrospective enrolled 75 patients who underwent low-kV CT with contrast media injection for general abdominal disorders and MRI with MRCP sequences. The reviewer, blinded to clinical and histopathological data, recorded the overall number of pancreatic cystic lesions, size, location, presence of calcifications, septa, or solid enhancing or non-enhancing components, main pancreatic duct (MPD) communication, and MPD dilatation. Mean differences with 95% limits of agreement, ICC, and κ statistics were used to compare CT and MRI.

RESULTS

More pancreatic cystic lesions were detected with MRI than with CT, however, the ICC value of 0.81 suggested a good agreement. According to the evaluated target lesion, a very good agreement (ICC = 0.98) was found regarding the diameter (21.4 mm CT vs 21.8 mm MRI), the location (κ = 0.90), the detection of MPD dilatation (κ = 1), the presence of septa (κ = 0.86) and the MPD communication (κ = 0.87). A moderate agreement on the assessment of enhanced components was noted (κ = 0.44), while there was only a fair agreement about the presence of calcifications (κ = 0.87).

CONCLUSION

MDCT can be considered almost equivalent to MRI with MRCP in the evaluation of worrisome features and high-risk stigmata, offering detailed morphologic features helpful for their characterization.

IMPLICATIONS FOR PRACTICE

Even if MRI is considered the reference standard in pancreatic cystic lesions characterization, CT can be considered a useful tool as a first-line imaging technique to identify worrisome features and high-risk stigmata.

Alterations in oxygen metabolism are associated to lung toxicity triggered by silver nanoparticles exposure

Along with the AgNP applications development, the concern about their possible toxicity has increasingly gained attention. As the respiratory system is one of the main exposure routes, the aim of this study was to evaluate the harmful effects developed in the lung after an acute AgNP exposure. In vivo studies using Balb/c mice intranasally instilled with 0.1 mg AgNP/kg b.w, were performed. ^99mTc-AgNP showed the lung as the main organ of deposition, where, in turn, AgNP may exert barrier injury observed by increased protein content and total cell count in BAL samples. In vivo acute exposure showed altered lung tissue O₂ consumption due to increased mitochondrial active respiration and NOX activity. Both O₂ consumption processes release ROS triggering the antioxidant system as observed by the increased SOD, catalase and GPx activities and a decreased GSH/GSSG ratio. In addition, increased protein oxidation was observed after AgNP exposure. In A549 cells, exposure to 2.5 μg/mL AgNP during 1 h resulted in augment NOX activity, decreased mitochondrial ATP associated respiration and higher H₂O₂ production rate. Lung 3D tissue model showed AgNP-initiated barrier alterations as TEER values decreased and morphological alterations. Taken together, these results show that AgNP exposure alters O₂ metabolism leading to alterations in oxygen metabolism lung toxicity. AgNP-triggered oxidative damage may be responsible for the impaired lung function observed due to alveolar epithelial injury.

Cutaneous antimicrobial peptides: New "actors" in pollution related inflammatory conditions

Ozone (O₃) exposure has been reported to contribute to various cutaneous inflammatory conditions, such as eczema, psoriasis, rush etc. via a redox-inflammatory pathway. O₃ is too reactive to penetrate cutaneous tissue; it interacts with lipids present in the outermost layer of skin, resulting in formation of oxidized molecules and hydrogen peroxide (H₂O₂). Interestingly, several inflammatory skin pathologies demonstrate altered levels of antimicrobial peptides (AMPs). These small, cationic peptides are found in various cells, including keratinocytes, eccrine gland cells, and seboctyes. Classically, AMPs function as antimicrobial agents. Recent studies indicate that AMPs also play roles in inflammation, angiogenesis, and wound healing. Since altered levels of AMPs have been detected in pollution-associated skin pathologies, we hypothesized that exposure to O₃ could affect the levels of AMPs in the skin. We examined levels of AMPs using qRT-PCR, Western blotting, and immunofluorescence in vitro (human keratinocytes), ex vivo (human skin explants), and in vivo (human volunteer subjects exposed to O₃) and observed increased levels of all the measured AMPs upon O₃ exposure. In addition, in vitro studies have confirmed the redox regulation of AMPs in keratinocytes. This novel finding suggests that targeting AMPs could be a possible defensive strategy to combat pollution-associated skin conditions.

•

AMPs (hBDs1-3, CAMP) increase in O₃ exposed human skin by a redox mechanism.

•

Transcriptional upregulation of AMPs in response to O₃ exposure is due to an altered redox status.

•

Pollution increase AMPs could be the connection between pollution exposure and the development/exacerbation of inflammatory skin conditions.

Impaired mitochondrial quality control in Rett Syndrome

Rett Syndrome (RTT) is a rare neurodevelopmental disorder caused in the 95% of cases by mutations in the X-linked MECP2 gene, affecting almost exclusively females. While the genetic basis of RTT is known, the exact pathogenic mechanisms that lead to the broad spectrum of symptoms still remain enigmatic. Alterations in the redox homeostasis have been proposed among the contributing factors to the development and progression of the syndrome. Mitochondria appears to play a central role in RTT oxidative damage and a plethora of mitochondrial defects has already been recognized. However, mitochondrial dynamics and mitophagy, which represent critical pathways in regulating mitochondrial quality control (QC), have not yet been investigated in RTT. The present work showed that RTT fibroblasts have networks of hyperfused mitochondria with morphological abnormalities and increased mitochondrial volume. Moreover, analysis of mitophagic flux revealed an impaired PINK1/Parkin-mediated mitochondrial removal associated with an increase of mitochondrial fusion proteins Mitofusins 1 and 2 (MFN1 and 2) and a decrease of fission mediators including Dynamin related protein 1 (DRP1) and Mitochondrial fission 1 protein (FIS1). Finally, challenging RTT fibroblasts with FCCP and 2,4-DNP did not trigger a proper apoptotic cell death due to a defective caspase 3/7 activation. Altogether, our findings shed light on new aspects of mitochondrial dysfunction in RTT that are represented by defective mitochondrial QC pathways, also providing new potential targets for a therapeutic intervention aimed at slowing down clinical course and manifestations in the affected patients.

A proteomics approach to further highlight the altered inflammatory condition in Rett syndrome

Rett syndrome (RTT) is a progressive neurodevelopmental disorder caused by mutations in the X-linked MECP2 gene. RTT patients show multisystem disturbances associated with perturbed redox homeostasis and inflammation, which appear as possible key factors in RTT pathogenesis. In this study, using primary dermal fibroblasts from control and RTT subjects, we performed a proteomic analysis that, together with data mining approaches, allowed us to carry out a comprehensive characterization of RTT cellular proteome. Functional and pathway enrichment analyses showed that differentially expressed proteins in RTT were mainly enriched in biological processes related to immune/inflammatory responses. Overall, by using proteomic data mining as supportive approach, our results provide a detailed insight into the molecular pathways involved in RTT immune dysfunction that, causing tissue and organ damage, can increase the vulnerability of affected patients to unknown endogenous factors or infections.

Evaluating the effect of ozone in UV induced skin damage

Air pollution represents one of the main risks for both environment and human health. The rapid urbanization has been leading to a continuous release of harmful manmade substances into the atmosphere which are associated to the exacerbation of several pathologies. The skin is the main barrier of our body against the external environment and it is the main target for the outdoor stressors. Among the pollutants, Ozone (O₃) is one of the most toxic, able to initiate oxidative reactions and activate inflammatory response, leading to the onset of several skin conditions. Moreover, skin is daily subjected to the activity of Ultraviolet Radiation which are well known to induce harmful cutaneous effects including skin aging and sunburn. Even though both UV and O₃ are able to affect the skin homeostasis, very few studies have investigated their possible additive effect. Therefore, in this study we evaluated the effect of the combined exposure of O₃ and UV in inducing skin damage, by exposing human skin explants to UV alone or in combination with O₃ for 4-days. Markers related to inflammation, redox homeostasis and tissue structure were analyzed. Our results demonstrated that O₃ is able to amplify the UV induced skin oxinflammation markers.

Postexercise Inflammasome Activation and IL-1β Production Mitigated by Flavonoid Supplementation in Cyclists

Inflammasomes are multiprotein signaling platforms of the innate immune system that detect markers of physiological stress and promote the maturation of caspase-1 and interleukin 1 beta (IL-1β), IL-18, and gasdermin D. This randomized, cross-over trial investigated the influence of 2-week mixed flavonoid (FLAV) versus placebo (PL) supplementation on inflammasome activation and IL-1β and IL-18 production after 75-km cycling in 22 cyclists (42 ± 1.7 years). Blood samples were collected before and after the 2-week supplementation, and then 0 hr, 1.5 hr, and 21 hr postexercise (176 ± 5.4 min, 73.4 ± 2.0 %VO2max). The supplement (678 mg FLAVs) included quercetin, green tea catechins, and bilberry anthocyanins. The pattern of change in the plasma levels of the inflammasome adaptor oligomer ASC (apoptosis-associated speck-like protein containing caspase recruitment domain) was different between the FLAV and PL trials, with the FLAV ASC levels 52% lower (Cohen's d = 1.06) than PL immediately following 75-km cycling (interaction effect, p = .012). The plasma IL-1β levels in FLAV were significantly lower than PL (23-42%; Cohen's d = 0.293-0.644) throughout 21 hr of recovery (interaction effect, p = .004). The change in plasma gasdermin D levels were lower immediately postexercise in FLAV versus PL (15% contrast, p = .023; Cohen's d = 0.450). The patterns of change in plasma IL-18 and IL-37 did not differ between the FLAV and PL trials (interaction effects, p = .388, .716, respectively). These data indicate that 2-week FLAV ingestion mitigated inflammasome activation, with a corresponding decrease in IL-1β release in cyclists after a 75-km cycling time trial. The data from this study support the strategy of ingesting high amounts of FLAV to mitigate postexercise inflammation.

Proteomic profiling reveals mitochondrial alterations in Rett syndrome

Rett syndrome (RTT) is a pervasive neurodevelopmental disorder associated with mutation in MECP2 gene. Despite a well-defined genetic cause, there is a growing consensus that a metabolic component could play a pivotal role in RTT pathophysiology. Indeed, perturbed redox homeostasis and inflammation, i.e. oxinflammation, with mitochondria dysfunction as the central hub between the two phenomena, appear as possible key contributing factors to RTT pathogenesis and its clinical features. While these RTT-related changes have been widely documented by transcriptomic profiling, proteomics studies supporting these evidences are still limited. Here, using primary dermal fibroblasts from control and patients, we perform a large-scale proteomic analysis that, together with data mining approaches, allow us to carry out the first comprehensive characterization of RTT cellular proteome, showing mainly changes in expression of proteins involved in the mitochondrial network. These findings parallel with an altered expression of key mediators of mitochondrial dynamics and mitophagy associated with abnormal mitochondrial morphology. In conclusion, our proteomic analysis confirms the pathological relevance of mitochondrial dysfunction in RTT pathogenesis and progression.

Inflammation in Neurological Disorders: The Thin Boundary Between Brain and Periphery

Significance: Accumulating evidence suggests that inflammation is a major contributor in the pathogenesis of several highly prevalent, but also rare, neurological diseases. In particular, the neurodegenerative processes of Alzheimer's disease (AD), vascular dementia (VAD), Parkinson's disease (PD), and multiple sclerosis (MS) are fueled by neuroinflammation, which, in turn, is accompanied by a parallel systemic immune dysregulation. This cross-talk between periphery and the brain becomes substantial when the blood-brain barrier loses its integrity, as often occurs in the course of these diseases. It has been hypothesized that the perpetual bidirectional flux of inflammatory mediators is not a mere "static" collateral effect of the neurodegeneration, but represents a proactive phenomenon sparking and driving the neuropathological processes. However, the upstream/downstream relationship between inflammatory events and neurological pathology is still unclear. Recent Advances: Solid recent evidence clearly suggests that metabolic factors, systemic infections, Microbiota dysbiosis, and oxidative stress are implicated, although to a different extent, in the development in brain diseases. Critical Issues: Here, we reviewed the most solid published evidence supporting the implication of the axis systemic inflammation-neuroinflammation-neurodegeneration in the pathogenesis of AD, VAD, PD, and MS, highlighting the possible cause of the putative downstream component of the axis. Future Directions: Reaching a definitive clinical/epidemiological appreciation of the etiopathogenic significance of the connection between peripheral and brain inflammation in neurologic disorders is pivotal since it could open novel therapeutic avenues for these diseases.

Additive effect of combined pollutants to UV induced skin OxInflammation damage. Evaluating the protective topical application of a cosmeceutical mixture formulation

Since the skin is one of the targets of the harmful effects of environmental insults, several studies have investigated the effects of outdoor stressors on cutaneous tissue. Ozone (O3), particulate matter (PM), and ultraviolet radiation (UV) have all been shown to induce skin damage through disruption of tissue redox homeostasis, resulting in the so called "OxInflammation" condition. However, few studies have explored whether these stressors can act synergistically in cutaneous tissues. In the present work, we evaluated whether O3, PM, and UV, which are the most common environmental skin insults, act synergistically in inducing skin damage, and whether this effect could be prevented through topical application of a cosmeceutical formulation mixture (CF Mix) containing 15% vitamin C (l-ascorbic acid), 1% vitamin E (α-tocopherol), and 0.5% ferulic acid. Human skin explants obtained from three different subjects were sequentially exposed to 200 mJ UV light, 0.25 ppm O3 for 2 h, and 30 min of diesel engine exhaust (DEE), alone or in combination for 4 days (time point D1 and D4). We observed a clear additive effect of O3 and DEE in combination with UV in increasing levels of several oxidative (4HNE, HO-1) and inflammatory (COX2, NF-κB) markers and loss of barrier-associated proteins, such as filaggrin and involucrin. Furthermore, daily topical pre-treatment with the CF Mix prevented upregulation of the inflammatory and oxidative markers and the loss of both involucrin and filaggrin. In conclusion, this study is the first to investigate the combined effects of three of the most harmful outdoor stressors on human skin and suggests that daily topical application may prevent pollution-induced skin damage.

Compromised immune/inflammatory responses in Rett syndrome

Mutations in X-linked gene methyl-CpG-binding protein 2 (MECP2), a key transcriptional regulator, account for most cases of Rett syndrome (RTT), a devastating neurodevelopmental disorder with no known cure. Despite extensive research to elucidate MeCP2 functions, the mechanisms underlying RTT pathophysiology are still unclear. In addition to a variety of neurological symptoms, RTT also includes a plethora of additional phenotypical features including altered lipid metabolism, redox imbalance, immune dysfunction and mitochondrial abnormalities that explain its multisystemic nature. Here, we provide an overview of the current knowledge on the potential role of dysregulated inflammatory and immune responses in RTT. The findings show that abnormalities of humoral and cell-mediated immunity together with chronic low-grade inflammation in multiple organs represent not only clinical manifestations of RTT but rather can contribute to its development and deteriorating course. A future research challenge could be to target therapeutically immune dysfunction as a novel means for RTT management.

Redox regulation of cutaneous inflammasome by ozone exposure

Several pollutants have been shown to affect skin physiology, among which ozone (O₃) is one of the most toxic. Prolonged exposure to O₃ leads to increased oxidative damage and cutaneous inflammation. The correlation between O₃ exposure and inflammatory cutaneous conditions (atopic dermatitis, psoriasis, acne and eczema) has been already suggested, although the mechanism involved is still unclear. In the last few decades, a new multiprotein complex, the inflammasome, has been discovered and linked to tissue inflammation, including inflammatory skin conditions. The inflammasome activates inflammatory responses and contributes to the maturation of cytokines such as interleukin 1β (IL-1β) and interleukin 18. This complex is also responsive to reactive oxygen species (ROS), which plays a role in triggering the activation of the complex. On this basis it is possible hypothesize that the activation of the inflammasome could be the link between the inflammatory skin conditions associated to O3 exposure. In the present work, the ability of O3 to induce inflammasome activation was determined in different skin models, ranging from 2D (human keratinocytes) to 3D models in vitro and ex vivo. Results clearly showed that O₃ exposure increased both transcript and protein levels of the main inflammasome complex, such as ASC and caspase-1. Furthermore, by using both immunofluorescence and an ASC oligomerization assay the formation of the complex was determined together with increased secreted levels of both IL-18 and IL-1β. Of note is that H2O2 and to a less extent 4HNE (both considered the main mediators of O3 interaction with cellular membranes) were also able to activate skin inflammasome while the use of catalase prevents the activation. This study demonstrated that O3 can activate cutaneous inflammasome in a redox dependent manner suggesting a possible role of this new pathway in pollution induced inflammatory skin conditions.

Protective effects of a comprehensive topical antioxidant against ozone-induced damage in a reconstructed human skin model

Tropospheric ozone (O₃) is a source of oxidative stress. This study examined the ability of a topical antioxidant (WEL-DS) to inhibit O₃-mediated damage in a human epidermal skin model. Four groups of tissues (N = 24) were compared: Group 1 (control) were untreated and unexposed; Group 2 were untreated and exposed to O₃ (0.4 ppm, 4 h); Group 3 were pretreated with WEL-DS and unexposed; Group 4 were pretreated with WEL-DS and exposed to O₃ (0.4 ppm, 4 h). Pretreated tissues were topically treated with 20 uL of WEL-DS and incubated for up to 20 h at 37 °C [humidified, 5% carbon dioxide (CO₂)]. After 24 h, tissues were re-treated with WEL-DS and exposed to O_3. Tissues were evaluated for Reactive Oxygen Species (ROS), hydrogen peroxide (H₂O₂), 4-hydroxynonenal (4-HNE) protein adducts, NF-κB p65 response and histology. In O₃-exposed groups, WEL-DS significantly inhibited ROS formation vs. untreated tissues (p < 0.05). Pretreatment with WEL-DS inhibited H₂O₂ production vs. untreated tissues (p < 0.05), and decreased NF-κB p65 transcription factor signal. Oxidative stress induction in O₃-exposed tissues was confirmed by increased levels of 4-HNE protein adducts (marker of lipid peroxidation); WEL-DS application reduced this effect. WEL-DS inhibited damage in tissues exposed to O₃ with no significant changes in epidermal structure. A comprehensive topical antioxidant significantly diminished O₃-induced oxidative damage in a human epidermal skin model.

Defective proteasome biogenesis into skin fibroblasts isolated from Rett syndrome subjects with MeCP2 non-sense mutations

Rett Syndrome (RTT) is a rare X-linked neurodevelopmental disorder which affects about 1: 10000 live births. In >95% of subjects RTT is caused by a mutation in Methyl-CpG binding protein-2 (MECP2) gene, which encodes for a transcription regulator with pleiotropic genetic/epigenetic activities. The molecular mechanisms underscoring the phenotypic alteration of RTT are largely unknown and this has impaired the development of therapeutic approaches to alleviate signs and symptoms during disease progression. A defective proteasome biogenesis into two skin primary fibroblasts isolated from RTT subjects harbouring non-sense (early-truncating) MeCP2 mutations (i.e., R190fs and R255X) is herewith reported. Proteasome is the proteolytic machinery of Ubiquitin Proteasome System (UPS), a pathway of overwhelming relevance for post-mitotic cells metabolism. Molecular, transcription and proteomic analyses indicate that MeCP2 mutations down-regulate the expression of one proteasome subunit, α7, and of two chaperones, PAC1 and PAC2, which bind each other in the earliest step of proteasome biogenesis. Furthermore, this molecular alteration recapitulates in neuron-like SH-SY5Y cells upon silencing of MeCP2 expression, envisaging a general significance of this transcription regulator in proteasome biogenesis.

Alterations of mitochondrial bioenergetics, dynamics, and morphology support the theory of oxidative damage involvement in autism spectrum disorder

Autism spectrum disorder (ASD) has been hypothesized to be a result of the interplay between genetic predisposition and increased vulnerability to early environmental insults. Mitochondrial dysfunctions appear also involved in ASD pathophysiology, but the mechanisms by which such alterations develop are not completely understood. Here, we analyzed ASD primary fibroblasts by measuring mitochondrial bioenergetics, ultrastructural and dynamic parameters to investigate the hypothesis that defects in these pathways could be interconnected phenomena responsible or consequence for the redox imbalance observed in ASD. High levels of 4-hydroxynonenal protein adducts together with increased NADPH (nicotinamide adenine dinucleotide phosphateoxidase) activity and mitochondrial superoxide production coupled with a compromised antioxidant response guided by a defective Nuclear Factor Erythroid 2-Related Factor 2 pathway confirmed an unbalanced redox homeostasis in ASD. Moreover, ASD fibroblasts showed overactive mitochondrial bioenergetics associated with atypical morphology and altered expression of mitochondrial electron transport chain complexes and dynamics-regulating factors. We suggest that many of the changes observed in mitochondria could represent compensatory mechanisms by which ASD cells try to adapt to altered energy demand, possibly resulting from a chronic oxinflammatory status.

Skin Health from the Inside Out

The skin is the main interface between the body and the environment, providing a biological barrier against an array of chemical and physical pollutants (e.g., ultraviolet light, ozone, etc.). Exposure of the skin to these outdoor stressors generates reactive oxygen species (ROS), which can overwhelm the skin's endogenous defense systems (e.g., catalase, vitamins C and E, etc.), resulting in premature skin aging due to the induction of DNA damage, mitochondrial damage, lipid peroxidation, activation of inflammatory signaling pathways, and formation of protein adducts. In this review, we discuss how topical application of antioxidants, including vitamins C and E, carotenoids, resveratrol, and pycnogenol, can be combined with dietary supplementation of these antioxidant compounds in addition to probiotics and essential minerals to protect against outdoor stressor-induced skin damage, including the damage associated with aging.

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.].

Multiple mechanisms of Rottlerin toxicity in A375 melanoma cells

Rottlerin is a cytostatic and cytotoxic drug in a variety of cancer cells. Our previous experience demonstrated that depending upon the genetic/biochemical background of cancer cells, rottlerin is able to induce both apoptotic and autophagic cell death, or dramatically disturb protein homeostasis leading to lethal cellular atrophy. In the current study, we investigated the cytotoxic effects and mechanisms of rottlerin against human amelanotic A375 melanoma cells. In this cell line, rottlerin exhibits its main and newest cytotoxic properties, that is, growth arrest, apoptosis induction, and translation shutoff. In fact, the drug, time-, and dose-dependently, markedly inhibited cell proliferation through cyclin D1 downregulation and induced apoptotic cell death as early as after 18 h treatment. Mechanistically, rottlerin triggered apoptosis by both intrinsic and extrinsic pathways. Both pathways are likely activated by the downregulation of the antiapoptotic B-cell lymphoma 2 (Bcl-2) protein, which simultaneously affects mitochondrial and endoplasmic reticulum (ER) membranes stability. Concomitantly to extrinsic apoptosis induction, the rottlerin-activated ER stress/eukaryotic initiation factor 2 (eIF2) α axis blocked the translational apparatus. The altered proteostasis precluded the complete cells' rescue from death in the presence of apoptosis inhibitors.

Gallic acid loaded poloxamer gel as new adjuvant strategy for melanoma: A preliminary study

The present study describes the production and characterization of poloxamer gels containing the antioxidant molecule gallic acid. The gels were particularly designed in order to obtain a formulation suitable for administration on the skin to treat melanoma. The polymer concentration was selected after rheological characterization and determination of gel transition temperature. In order to study the gallic acid diffusion, in vitro experiments were performed using Franz cells associated to different membranes. As first approach the gallic acid diffusion was evaluated through synthetic membranes, such as cellulose, nylon, polycarbonate, polytetrafluoroethylene, polyvinylidene fluoride and the commercial Strat-M® membrane. The membranes were employed separately or in association and compared to stratum corneum epidermis membranes, in order to find a system able to reproduce the gallic acid diffusion through the skin. Selected membranes were used for studying gallic acid diffusion from poloxamer gel. It was found that the diffusion of gallic acid was dramatically influenced by the type of membrane, both in the case of the aqueous solution or poloxamer gel. Scratch wound healing and migration assays conducted on human keratinocytes and melanoma cells demonstrated the ability of gallic acid loaded gel to inhibit cellular migration, suggesting its potential as adjuvant strategy for melanoma.

Altered inflammasome machinery as a key player in the perpetuation of Rett syndrome oxinflammation

Rett syndrome (RTT) is a progressive neurodevelopmental disorder mainly caused by mutations in the X-linked MECP2 gene. RTT patients show multisystem disturbances associated with an oxinflammatory status. Inflammasomes are multi-protein complexes, responsible for host immune responses against pathogen infections and redox-related cellular stress. Assembly of NLRP3/ASC inflammasome triggers pro-caspase-1 activation, thus, resulting in IL-1β and IL-18 maturation. However, an aberrant activation of inflammasome system has been implicated in several human diseases. Our aim was to investigate the possible role of inflammasome in the chronic subclinical inflammatory condition typical of RTT, by analyzing this complex in basal and lipopolysaccharide (LPS)+ATP-stimulated primary fibroblasts, as well as in serum from RTT patients and healthy volunteers. RTT cells showed increased levels of nuclear p65 and ASC proteins, pro-IL-1β mRNA, and NLRP3/ASC interaction in basal condition, without any further response upon the LPS + ATP stimuli. Moreover, augmented levels of circulating ASC and IL-18 proteins were found in serum of RTT patients, which are likely able to amplify the inflammatory response. Taken together, our findings suggest that RTT patients exhibited a challenged inflammasome machinery at cellular and systemic level, which may contribute to the subclinical inflammatory state feedback observed in this pathology.

•

RTT cell shows a constitutive NFκB activation.

•

Aberrant activation of inflammasome system is evident in RTT.

•

This new evidence can explain the demonstrated subclinical inflammation in RTT.

Involvement of 4-hydroxy-2-nonenal in pollution-induced skin damage

The effects of environmental insults on human health are a major global concern. Some of the most noxious pollutants that humans are exposed to include ozone (O₃ ), particulate matter (PM), and cigarette smoke (CS). Since the skin is the first line of defense against environmental insults, it is considered one of the main target organs for the harmful insults of air pollution. Thus, there is solid evidence that skin pathologies such as premature aging, atopic dermatitis (AD), and psoriasis are associated with pollutant exposure; all of these skin conditions are also associated with an altered redox status. Therefore, although the mechanisms of action and concentrations of O₃ , PM, and CS that we are exposed to differ, exposure to all of these pollutants is associated with the development of similar skin conditions due to the fact that all of these pollutants alter redox homeostasis, increasing reactive oxygen species production and oxidative stress. A main product of oxidative stress, induced by exposure to the aforementioned pollutants, is 4-hydroxy-2-nonenal (HNE), which derives from the oxidation of ω-6 polyunsaturated fatty acids. HNE is a highly reactive compound that can form adducts with cellular proteins and even DNA; it is also an efficient cell signaling molecule able to regulate mitogen-activated protein kinase pathways and the activity of redox-sensitive transcription factors such as Nrf2, AP1, and NFκB. Therefore, increased levels of HNE in the skin, in response to pollutants, likely accelerates skin aging and exacerbates existing skin inflammatory conditions; thus, targeting HNE formation could be an innovative cosmeceutical approach for topical applications.

13-HODE, 9-HODE and ALOX15 as potential players in Rett syndrome OxInflammation

Mutations in the MECP2 gene are the main cause of Rett syndrome (RTT), a pervasive neurodevelopmental disorder, that shows also multisystem disturbances associated with a metabolic component. The aim of this study was to investigate whether an increased production of oxidized linoleic acid metabolites, specifically 9- and 13-hydroxyoctadecadienoic acids (HODEs), can contribute to the altered the redox and immune homeostasis, suggested to be involved in RTT. Serum levels of 9- and 13-HODEs were elevated in RTT and associated with the expression of arachidonate 15-Lipoxygenase (ALOX15) in peripheral blood mononuclear cells (PBMCs). Omega-3 polyunsaturated fatty acids supplementation has shown to lower HODEs levels in RTT. Statistically significant correlation was demonstrated between the increased plasma HODEs levels and the lipoprotein-associated phospholipase A2 (Lp-PLA2) activity. Collectively, these findings reinforce the concept of the key role played by lipid peroxidation in RTT, and the possible ability of omega-3 polyunsaturated fatty acids supplementation in improving the oxinflammation status in RTT.

Antiglycative Activity and RAGE Expression in Rett Syndrome

Rett syndrome (RTT) is a human neurodevelopmental disorder, whose pathogenesis has been linked to both oxidative stress and subclinical inflammatory status (OxInflammation). Methylglyoxal (MG), a glycolytic by-product with cytotoxic and pro-oxidant power, is the major precursor in vivo of advanced glycation end products (AGEs), which are known to exert their detrimental effect via receptor- (e.g., RAGE) or non-receptor-mediated mechanisms in several neurological diseases. On this basis, we aimed to compare fibroblasts from healthy subjects (CTR) with fibroblasts from RTT patients (N = 6 per group), by evaluating gene/protein expression patterns, and enzymatic activities of glyoxalases (GLOs), along with the levels of MG-dependent damage in both basal and MG-challenged conditions. Our results revealed that RTT is linked to an alteration of the GLOs system (specifically, increased GLO2 activity), that ensures unchanged MG-dependent damage levels. However, RTT cells underwent more pronounced cell death upon exogenous MG-treatment, as compared to CTR, and displayed lower RAGE levels than CTR, with no alterations following MG-treatment, thus suggesting that an adaptive response to dicarbonyl stress may occur. In conclusion, besides OxInflammation, RTT is associated with reshaping of the major defense systems against dicarbonyl stress, along with an altered cellular stress response towards pro-glycating insults.

Clinical Impact and Safety of Anticoagulants for Portal Vein Thrombosis in Cirrhosis

OBJECTIVES

Portal vein thrombosis (PVT) is a frequent complication of cirrhosis. Benefit, safety, and duration of anticoagulant treatment in this setting are controversial issues. The aim of this study was to analyze the course of PVT in a large cohort of cirrhotic patients undergoing or not anticoagulation therapy.

METHODS

The data of 182 patients who presented between January 2008 and March 2016 with cirrhosis and PVT with at least 3 months of follow-up after the first PVT detection were analyzed. Eighty-one patients received anticoagulants and 101 were untreated per physician discretion.

RESULTS

The extension of the thrombosis decreased by >50% in 46 (56.8%, with complete recanalization in 31/46) patients under anticoagulation and in 26 (25.7%) untreated patients. Of the 46 patients who underwent recanalization, 17 (36%) suffered recurrent thrombosis after stopping anticoagulation therapy. Kaplan-Meier analysis showed a higher survival rate in the treated group (p = 0.010). At multivariate analysis, anticoagulation was an independent factor associated with longer survival (HR:0.30, CI:0.10-0.91, p = 0.014). The Child-Turcotte-Pugh classes B/C negatively influenced survival (hazard ratio, (HR):3.09, confidence interval (CI):1.14-8.36, p = 0.027 for Child-Turcotte-Pugh B and HR:9.27, CI:2.67-32.23, p < 0.001 for Child-Turcotte-Pugh C). Bleeding complications occurred in 22 (21.8%) untreated and 16 (19.7%) treated patients, but in only four cases was it judged to be related to the anticoagulant treatment. No death was reported as a consequence of the bleeding events.

CONCLUSIONS

Anticoagulant treatment is a safe and effective treatment leading to partial or complete recanalization of the portal venous system in 56.8% of cases, improving the survival of patients with cirrhosis and PVT. Discontinuation of the therapy is associated with a high rate of PVT recurrence.

Production and Characterization of Nanoparticle Based Hyaluronate Gel Containing Retinyl Palmitate for Wound Healing

BACKGROUND

Wound healing is a biological process that can get in a state of pathologic inflammation, requiring the use of specific medications able to promote proper tissue repair.

OBJECTIVE

The study describes the production and characterization of nanoparticle based gel for wound healing treatment designed to deliver hyaluronic acid and retinyl palmitate onto the skin.

METHODS

Tristearin solid lipid nanoparticles and nanostructured lipid carriers based on a tristearin and caprylic/capric triglyceride mixture were produced and characterized. Gel spreadability and viscosity were investigated. Drug diffusion and "in vitro" wound healing were assessed by Franz cell and scratch wound assay in keratinocytes.

RESULTS

Cryogenic transmission electron microscopy evidenced flat discoid nanoparticles. Photon correlation spectroscopy analysis indicated homogeneous dimensional distribution and mean diameter 132±46 nm. X-ray evidenced a lamellar inner structure of lipid nanoparticles. Nanostructured lipid carriers, being based on a heterogeneous solid/ liquid lipid mixture, could better solubilize retinyl palmitate and control its stability. The hyaluronic acid directly added into nanoparticles' dispersion enabled to obtain a shear-thinning gel suitable for cutaneous administration. Retynil palmitate diffusion was slower from the nanoparticulate gel with respect to the plain nanoparticle dispersion. The "wound healing" effect of nanoparticulate gel containing retinyl palmitate and hyaluronic acid, analyzed in HaCaT cells, showed significant differences in wounded areas between treated and control cells during the first 24 h postwounding suggesting a synergic effect of retinyl palmitate and hyaluronic acid in "in vitro" wound healing.

CONCLUSIONS

This study suggests that a nanoparticle based hyaluronate gel containing retinyl palmitate can be efficiently used for wound healing.