Oreoch-1: A broad-spectrum virus and host-targeting peptide against animal infections.

In recent decades, the global rise of viral emerging infectious diseases has posed a substantial threat to both human and animal health worldwide. The rapid spread and accumulation of mutations into viruses, and the limited availability of antiviral drugs and vaccines, stress the urgent need for alternative therapeutic strategies. Antimicrobial peptides (AMPs) derived from natural sources present a promising avenue due to their specificity and effectiveness against a broad spectrum of pathogens. The present study focuses on investigating the antiviral potential of oreochromicin-1 (oreoch-1), a fish-derived AMP obtained from Nile tilapia, against a wide panel of animal viruses including canine distemper virus (CDV), Schmallenberg virus (SBV), caprine herpesvirus 1 (CpHV-1), and bovine herpesvirus 1 (BoHV-1). Oreoch-1 exhibited a strong antiviral effect, demonstrating an inhibition of infection at concentrations in the micromolar range. The mechanism of action involves the interference with viral entry into host cells and a direct interaction between oreoch-1 and the viral envelope. In addition, we observed that the peptide could also interact with the cell during the CDV infection. These findings not only highlight the efficacy of oreoch-1 in inhibiting viral infection but also emphasize the potential of fish-derived peptides, specifically oreoch-1, as effective antiviral agents against viral infections affecting animals, whose potential to spill into humans is high. This research contributes valuable insights to the ongoing quest for novel antiviral drugs with the potential to mitigate the impact of infectious diseases on a global scale.

Cupferron impairs the growth and virulence of Escherichia coli clinical isolates.

AIMS: Multidrug resistance is a worrying problem worldwide. The lack of readily available drugs to counter nosocomial infections requires the need for new interventional strategies. Drug repurposing represents a valid alternative to using commercial molecules as antimicrobial agents in a short time and with low costs. Contextually, the present study focused on the antibacterial potential of the ammonium salt N-nitroso-N-phenylhydroxylamine (Cupferron), evaluating the ability to inhibit microbial growth and influence the main virulence factors. METHODS AND RESULTS: Cupferron cytotoxicity was checked via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and hemolysis assays. The antimicrobial activity was assessed through the Kirby-Bauer disk diffusion test, broth microdilution method, and time-killing kinetics. Furthermore, the impact on different stages of the biofilm life cycle, catalase, swimming, and swarming motility was estimated via MTT and crystal violet (CV) assay, H2O2 sensitivity, and motility tests, respectively. Cupferron exhibited <15% cytotoxicity at 200 µg/mL concentration. The 90% bacterial growth inhibitory concentrations (MIC90) values recorded after 24 hours of exposure were 200 and 100 µg/mL for multidrug-resistant (MDR) and sensitive strains, respectively, exerting a bacteriostatic action. Cupferron-treated bacteria showed increased susceptibility to biofilm production, oxidative stress, and impaired bacterial motility in a dose-dependent manner. CONCLUSIONS: In the new antimicrobial compounds active research scenario, the results indicated that Cupferron could be an interesting candidate for tackling Escherichia coli infections.

Galdieria sulphuraria: An Extremophilic Alga as a Source of Antiviral Bioactive Compounds.

In the last decades, the interest in bioactive compounds derived from natural sources including bacteria, fungi, plants, and algae has significantly increased. It is well-known that aquatic or terrestrial organisms can produce, in special conditions, secondary metabolites with a wide range of biological properties, such as anticancer, antioxidant, anti-inflammatory, and antimicrobial activities. In this study, we focused on the extremophilic microalga Galdieria sulphuraria as a possible producer of bioactive compounds with antiviral activity. The algal culture was subjected to organic extraction with acetone. The cytotoxicity effect of the extract was evaluated by the 2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. The antiviral activity was assessed through a plaque assay against herpesviruses and coronaviruses as enveloped viruses and poliovirus as a naked one. The monolayer was treated with different concentrations of extract, ranging from 1 µg/mL to 200 µg/mL, and infected with viruses. The algal extract displayed strong antiviral activity at non-toxic concentrations against all tested enveloped viruses, in particular in the virus pre-treatment against HSV-2 and HCoV-229E, with IC50 values of 1.7 µg/mL and IC90 of 1.8 µg/mL, respectively. However, no activity against the non-enveloped poliovirus has been detected. The inhibitory effect of the algal extract was confirmed by the quantitative RT-PCR of viral genes. Preliminary chemical profiling of the extract was performed using ultra-high-performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS), revealing the enrichment in primary fatty acid amides (PFAA), such as oleamide, palmitamide, and pheophorbide A. These promising results pave the way for the further purification of the mixture to explore its potential role as an antiviral agent.

Hylin-a1: A Pan-Inhibitor against Emerging and Re-Emerging Respiratory Viruses.

Pandemic and epidemic outbreaks of respiratory viruses are a challenge for public health and social care system worldwide, leading to high mortality and morbidity among the human populations. In light of the limited efficacy of current vaccines and antiviral drugs against respiratory viral infections and the emergence and re-emergence of new viruses, novel broad-spectrum antiviral drugs are needed for the prevention and treatment of these infections. Antimicrobial peptides with an antiviral effect, also known as AVPs, have already been reported as potent inhibitors of viral infections by affecting different stages of the virus lifecycle. In the present study, we analyzed the activity of the AVP Hylin-a1, secreted by the frog Hypsiboas albopunctatus, against a wide range of respiratory viruses, including the coronaviruses HCoV-229E and SARS-CoV-2, measles virus, human parainfluenza virus type 3, and influenza virus H1N1. We report a significant inhibitory effect on infectivity in all the enveloped viruses, whereas there was a lack of activity against the naked coxsackievirus B3. Considering the enormous therapeutic potential of Hylin-a1, further experiments are required to elucidate its mechanism of action and to increase its stability by modifying the native sequence.

Hepatitis B Virus prevalence and serological profiles in a hospital in Southern Italy.

Viral hepatitis still represents a significant worldwide public health issue, being an important cause of morbidity and mortality. The aim of our study is to evaluate the prevalence of Hepatitis B virus (HBV) markers from serologic analysis of hospitalized patients at University Hospital of Campania "Luigi Vanvitelli" and also to investigate the prevalence of HBV/HCV coinfection. We screened serum Anti-Hepatitis B surface antigen (HBsAg), antibody to HBsAg (anti-HBs), antibody to hepatitis B core antigen (anti-HBc), and antibody to Hepatitis C Virus (Anti-HCV) Anti-HCV from January to December 2020. Analyses of HBV serological profile based on age showed that the 51-60 age group was the most numerous and with the highest cases of HBsAg. The 61-70 age group recorded the highest prevalence of anti-HBc while age groups 0-10 years and 31-40 years the highest cases of anti-HBs. Antibody levels decline with time. In subjects older than 20 years, compared to vaccinated cohort individuals, anti-HBc seropositive prevalence increased linearly. This study underlined, in our geographic region, the decreased incidence of hepatitis B and high immunogenicity in the young population. Therefore, administration of HBV vaccine booster dose should be considered for the population rather than vaccination in the first year of life. In conclusion, our findings reaffirm the importance of health surveillance in hospitalized subjects, stressing the need to improve immunized subjects to increase the general population's health.

Antimicrobial resistance changing trends of Klebsiella pneumoniae isolated over the last 5 years.

The aim of this study was to describe the prevalence and epidemiology distribution of K. pneumoniae isolated at University Hospital of Campania "Luigi Vanvitelli," including the susceptibility evolution profile. Data on resistant phenotype strains, such as extended-spectrum-ß-lactamase (ESBL) producers and carbapenem-resistant K. pneumoniae (CRE) isolates, were also reported. K. pneumoniae strains were collected at the Complex Operative Unit (UOC) of Virology and Microbiology from different colonization and infection sites from January 2016 to December 2020. The highest rates of isolation were in urinary samples and in respiratory and wound swabs. Antibiotics susceptibility patterns showed more than 50% of the isolates resistant to cephalosporins, fluoroquinolones and penicillin. On the other hand, from 20% to 40% of K. pneumoniae strains were resistant to carbapenems and aminoglycosides. Based on our analysis, fosfomycin, ceftazidime/avibactam and ceftolozane/tazobactam are still therapeutic alternatives. Data analysis on carbapenem class evolution in 2016-2020 showed a significant increase in resistance rates (p<0.05). Increased rates in CRE and ESBL producing K. pneumoniae since 2017 were reported. Providing information on clinical characteristics and epidemiology data on contemporary K. pneumoniae evolution could help mitigate the spread of these isolates in our hospital and avert the endemic levels that have been observed in Southern Italy and in other European countries.

The Broad-Spectrum Antiviral Potential of the Amphibian Peptide AR-23.

Viral infections represent a serious threat to the world population and are becoming more frequent. The search and identification of broad-spectrum antiviral molecules is necessary to ensure new therapeutic options, since there is a limited availability of effective antiviral drugs able to eradicate viral infections, and consequently due to the increase of strains that are resistant to the most used drugs. Recently, several studies on antimicrobial peptides identified them as promising antiviral agents. In detail, amphibian skin secretions serve as a rich source of natural antimicrobial peptides. Their antibacterial and antifungal activities have been widely reported, but their exploitation as potential antiviral agents have yet to be fully investigated. In the present study, the antiviral activity of the peptide derived from the secretion of Rana tagoi, named AR-23, was evaluated against both DNA and RNA viruses, with or without envelope. Different assays were performed to identify in which step of the infectious cycle the peptide could act. AR-23 exhibited a greater inhibitory activity in the early stages of infection against both DNA (HSV-1) and RNA (MeV, HPIV-2, HCoV-229E, and SARS-CoV-2) enveloped viruses and, on the contrary, it was inactive against naked viruses (PV-1). Altogether, the results indicated AR-23 as a peptide with potential therapeutic effects against a wide variety of human viruses.

Broad-Spectrum Antiviral Activity of the Amphibian Antimicrobial Peptide Temporin L and Its Analogs.

The COVID-19 pandemic has evidenced the urgent need for the discovery of broad-spectrum antiviral therapies that could be deployed in the case of future emergence of novel viral threats, as well as to back up current therapeutic options in the case of drug resistance development. Most current antivirals are directed to inhibit specific viruses since these therapeutic molecules are designed to act on a specific viral target with the objective of interfering with a precise step in the replication cycle. Therefore, antimicrobial peptides (AMPs) have been identified as promising antiviral agents that could help to overcome this limitation and provide compounds able to act on more than a single viral family. We evaluated the antiviral activity of an amphibian peptide known for its strong antimicrobial activity against both Gram-positive and Gram-negative bacteria, namely Temporin L (TL). Previous studies have revealed that TL is endowed with widespread antimicrobial activity and possesses marked haemolytic activity. Therefore, we analyzed TL and a previously identified TL derivative (Pro3, DLeu9 TL, where glutamine at position 3 is replaced with proline, and the D-Leucine enantiomer is present at position 9) as well as its analogs, for their activity against a wide panel of viruses comprising enveloped, naked, DNA and RNA viruses. We report significant inhibition activity against herpesviruses, paramyxoviruses, influenza virus and coronaviruses, including SARS-CoV-2. Moreover, we further modified our best candidate by lipidation and demonstrated a highly reduced cytotoxicity with improved antiviral effect. Our results show a potent and selective antiviral activity of TL peptides, indicating that the novel lipidated temporin-based antiviral agents could prove to be useful additions to current drugs in combatting rising drug resistance and epidemic/pandemic emergencies.

Natural Formulations Based on Olea europaea L. Fruit Extract for the Topical Treatment of HSV-1 Infections.

In the present study, a hydroxytyrosol-rich Olea europaea L. fruit extract (OFE) was added to three thoroughly green formulations-hydrogel, oleogel, and cream-in order to evaluate their antiviral activity against HSV-1. The extract was characterized by different analytical techniques, i.e., FT-IR, XPS, and TGA. HPLC analyses were carried out to monitor the content and release of hydroxytyrosol in the prepared formulations. The total polyphenol content and antioxidant activity were investigated through Folin-Ciocâlteu's reagent, DPPH, and ABTS assays. The ability of the three formulations to convey active principles to the skin was evaluated using a Franz cell, showing that the number of permeated polyphenols in the hydrogel (272.1 ± 1.8 GAE/g) was significantly higher than those in the oleogel and cream (174 ± 10 and 179.6 ± 2 GAE/g, respectively), even if a negligible amount of hydroxytyrosol crossed the membrane for all the formulations. The cell viability assay indicated that the OFE and the three formulations were not toxic to cultured Vero cells. The antiviral activity tests highlighted that the OFE had a strong inhibitory effect against HSV-1 with a 50% inhibitory concentration (IC50) at 25 µg/mL, interfering directly with the viral particles. Among the three formulations, the hydrogel exhibited the highest antiviral activity also against the acyclovir-resistant strain.

Q-switched Nd-YAG laser alone and in combination with innovative hyaluronic acid gels improve keratinocytes wound healing in vitro.

During the last years, several attempts have been accomplished to improve the wound healing. Device application aimed at enhancing skin ability to reconstruct its damaged sites through a proper dermal regenerative process. In particular, Q-switched Nd-YAG laser (Medlite C6 laser, Conbio, USA) applied with a fluence of 8 J/cm2, a pulse width of 5 ns, and a spot size of 4 mm exerts a photo-mechanical action that improve skin repair. Besides, hyaluronan hybrid cooperative complexes (HCC) widely exploited in dermoesthetic applications proved specific actions on keratinocytes and fibroblasts monolayer repair. We evaluated this specific laser treatment in vitro on a wound healing model based on human keratinocytes (HaCaT) alone and in combination with HCC. In addition, we evaluated key biomarkers of dermal repair. Scratched HaCaT monolayers were treated with laser and successively with HA-based formulations (HHA and HCC). For each treatment and the control samples, at least 3 different wells were analyzed. Wound closure was quantified, measuring five view filed for each well at increasing incubation time, exploiting time lapse videomicroscopy and image analysis, permitting to compare the different healing rate of treatments respect to control. By real-time PCR and western blotting, we evaluated biomarkers of wound regeneration, such as integrins, aquaporin three (AQP3), and proinflammatory cytokines. The ANOVA test was used to assess statistical significance of the results obtained. Laser-treated cells achieved wound closure in about 37 h, faster than the control, while when coupled to HCC, the complete reparation was obtained in 24 h. Integrin αV was upregulated by treatments, with in particular about four-fold increase respect to the control when HCC + laser was used. In addition, integrin ß3 was upregulated by all treatments especially with the combination of laser and HCC proved more efficient than others (~ 14-folds). A slighter but significant increase of AQP3 gene expression of 61% was found for laser treatment while the latter combined with HCC determined an upregulation of 72%. By coupling laser treatment and HCC, further healing improvement and consistent biomarker modulation was observed. Our results may support clinical implementation of new dermatology protocols conjugating laser treatments with topical or injective HA formulations as a valid tool in treatments to repair scars or other skin defects.

Gene Transfer Potential of Outer Membrane Vesicles of Gram-Negative Bacteria.

The increasing spread of multidrug-resistant pathogenic bacteria is one of the major threats to public health worldwide. Bacteria can acquire antibiotic resistance and virulence genes through horizontal gene transfer (HGT). A novel horizontal gene transfer mechanism mediated by outer membrane vesicles (OMVs) has been recently identified. OMVs are rounded nanostructures released during their growth by Gram-negative bacteria. Biologically active toxins and virulence factors are often entrapped within these vesicles that behave as molecular carriers. Recently, OMVs have been reported to contain DNA molecules, but little is known about the vesicle packaging, release, and transfer mechanisms. The present review highlights the role of OMVs in HGT processes in Gram-negative bacteria.

Outer Membrane Vesicles Derived from Klebsiella pneumoniae Are a Driving Force for Horizontal Gene Transfer.

Gram-negative bacteria release Outer Membrane Vesicles (OMVs) into the extracellular environment. Recent studies recognized these vesicles as vectors to horizontal gene transfer; however, the parameters that mediate OMVs transfer within bacterial communities remain unclear. The present study highlights for the first time the transfer of plasmids containing resistance genes via OMVs derived from Klebsiella pneumoniae (K. pneumoniae). This mechanism confers DNA protection, it is plasmid copy number dependent with a ratio of 3.6 times among high copy number plasmid (pGR) versus low copy number plasmid (PRM), and the transformation efficiency was 3.6 times greater. Therefore, the DNA amount in the vesicular lumen and the efficacy of horizontal gene transfer was strictly dependent on the identity of the plasmid. Moreover, the role of K. pneumoniae-OMVs in interspecies transfer was described. The transfer ability was not related to the phylogenetic characteristics between the donor and the recipient species. K. pneumoniae-OMVs transferred plasmid to Escherichia coli, Salmonella enterica, Pseudomonas aeruginosa and Burkholderia cepacia. These findings address the pivotal role of K. pneumoniae-OMVs as vectors for antimicrobial resistance genes spread, contributing to the development of antibiotic resistance in the microbial communities.

Synthesis of novel lignan-like compounds and their antimicrobial activity.

Herein we report the preparation of 3,4-dibenzylfurans and some oxidized derivatives with lignan backbone. The compounds were prepared using the Friedel-Crafts reaction with BF3 etherate as catalyst, demethylation with iodocyclohexane, acetylation and oxidation reactions. The antimicrobial activity was evaluated through their capacity to inhibit the growth of Gram positive and Gram negative bacteria, and of the yeast Candida albicans. Among ten products assayed four furans displayed a good antimicrobial activity against Staphylococcus aureus, S. epidermidis and C. albicans; on the contrary, none of the compounds were active against Pseudomonas aeruginosa. One of them inhibited the growth of S. aureus, S. epidermidis (biofilm producer strain) and C. albicans at 16 µg/mL, showing a bactericidal activity already after one hour of treatment. In summary, the results suggest a possible use of these derivatives for general disinfection practices or antimicrobial agents in cosmesis skin-care.

Gastrointestinal Disorders and Metabolic Syndrome: Dysbiosis as a Key Link and Common Bioactive Dietary Components Useful for their Treatment.

Gastrointestinal (GI) diseases, which include gastrointestinal reflux disease, gastric ulceration, inflammatory bowel disease, and other functional GI disorders, have become prevalent in a large part of the world population. Metabolic syndrome (MS) is cluster of disorders including obesity, hyperglycemia, hyperlipidemia, and hypertension, and is associated with high rate of morbidity and mortality. Gut dysbiosis is one of the contributing factors to the pathogenesis of both GI disorder and MS, and restoration of normal flora can provide a potential protective approach in both these conditions. Bioactive dietary components are known to play a significant role in the maintenance of health and wellness, as they have the potential to modify risk factors for a large number of serious disorders. Different classes of functional dietary components, such as dietary fibers, probiotics, prebiotics, polyunsaturated fatty acids, polyphenols, and spices, possess positive impacts on human health and can be useful as alternative treatments for GI disorders and metabolic dysregulation, as they can modify the risk factors associated with these pathologies. Their regular intake in sufficient amounts also aids in the restoration of normal intestinal flora, resulting in positive regulation of insulin signaling, metabolic pathways and immune responses, and reduction of low-grade chronic inflammation. This review is designed to focus on the health benefits of bioactive dietary components, with the aim of preventing the development or halting the progression of GI disorders and MS through an improvement of the most important risk factors including gut dysbiosis.

Effects of ultra-weak fractal electromagnetic signals on the aqueous phase in living systems: a test-case analysis of molecular rejuvenation markers in fibroblasts.

Skin aging is primarily associated with the alterations in dermal extracellular matrix, in particular a decrease in collagen type-1 content. Recent studies have shown that collagen-degrading matrix metalloproteinase (MMP-1) is produced by fibroblasts in response to chronoaging, which in human dermal fibroblasts leads to the release of proinflammatory cytokines. Past studies showed that anti-inflammatory capabilities could be induced via non-chemical means. One of these methods makes use of ultra-weak fractal electromagnetic (uwf-EM) signals. Such ultra-/very-low frequency (U/VLF) signals (few nT in intensity and within 0.5-30 kHz) interact with aqueous solutions in living systems. The fractal nature of such EM-signals relates to the self-similar property by which a "cut-out" and magnified piece of this signal reveals again the original. Thus, the aim of this study is twofold, to i) investigate the extent of this modulating effect using Human Dermal Fibroblasts (HDF)-cells, and ii) analyse molecular rejuvenation markers therein. We could demonstrate that a 10 min uwf-EM exposure (prior to incubation) increases type-1 collagen and modulates elastin in human fibroblasts cultured up to 96 h, while at the same time reduces IL-6, TNF-α and MMP-1 (the later three being statistically significant). Such up- respectively down-regulation of corresponding genes are strong indicators of an EM-induced hormetic effect that influences the epigenomic landscape of HDFs. In the Appendix, we present, in the framework of Quantum Field Theory (QFT), water as a biphasic liquid and how its coherent fraction can be affected by uwf-EM signals while at the same time resolving the "kT paradox".

Q-switched 1064 nm Nd-Yag nanosecond laser effects on skin barrier function and on molecular rejuvenation markers in keratinocyte-fibroblasts interaction.

Skin represents an interface between internal and external environment; it protects human body by regulating the water loss and the maintenance of body temperature, defending against irritant and pathogen agents, and against physical, chemical, and UV damage. It provides to essential physiological functions, such as the important antioxidant defense capacity; its protective/defensive function is performed by a high number of proteins, and shows important functions in maintenance of skin barrier homeostasis. Keratinocytes and fibroblasts play a pivotal role to determine or prevent skin aging in response to intrinsic or extrinsic stimuli, modulating cytokines and several biochemical factors. Non-ablative technologies are playing an increasing role in the management of skin aging, inducing a dermal remodeling without a visible epidermal damage. The objective of this study was to evaluate the effect of Q-switched 1064 Nd-YAG laser (Medlite Conbio C6 Nd-YAG laser, Cynosure USA) in skin barrier function, analyzing the constituents which are strongly altered in aging skin. Particularly, we evaluated the expression of filaggrin, TGase, HSP70, and aquaporins, on HaCaT cells. The expression of proinflammatory cytokines has been investigated too.As a second step of the study, we analyzed the modulation of the rejuvenation molecular markers on human skin fibroblasts (HDFs) stimulated with keratinocytes conditioned medium (KCM).Our results demonstrated that Q-switched 1064 nm Nd:YAG laser acts on the skin barrier function, increasing the expression of aquaporins, filaggrin, TGase, and HSP70, modulating the proinflammatory cytokines. In fibroblasts stimulated with keratinocytes conditioned medium (KCM) and irradiated with Q-switched 1064 nm Nd:YAG laser, we can observe a reduction of MMP-1 and an increase in procollagen, collagen type I, and elastin. Our results highlight that Q-switched 1064 nm Nd:YAG laser treatment could represent an effective weapon to fight skin aging.

Antimicrobial and anti-biofilm properties of novel synthetic lignan-like compounds.

Antibiotic resistance and biofilm tolerance are among the principal factors involved in the persistence of chronic infections. The need for new antimicrobials is an ever-increasing challenge in clinical environments and in the control of global health. Arylfurans form a set of structures that have been identified in many natural products, e.g. lignans. Lignans are a sub-group of non-flavonoid polyphenols that play an active role in plants' defense against bacteria and fungi infections. The aim of this study was to identify novel synthetic arylfurans and lignan-like arylbenzylfurans exhibiting antimicrobial properties. The molecules synthetized were tested against Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus and S. epidermidis. We found that among tested compounds, arylbenzylfuran 11 was active against S. aureus and S. epidermidis with an MIC of 4 µg ml-1. Compound 11 was also active on methicillin-resistant S. aureus and S. epidermidis. By confocal laser scanning microscopy, we showed that 32 µg ml-1 of compound 11 was able to induce a significant reduction in S. aureus and S. epidermidis biofilms viability. Finally, we demonstrated that compound 11 was not cytotoxic on HaCat cells up to 128 µg ml-1. This work shows the antimicrobial and anti-biofilm potential of a synthetic lignan-like furan.

Malassezia pachydermatis up-regulates AhR related CYP1A1 gene and epidermal barrier markers in human keratinocytes.

Cytochrome P450 CYP1A1 and CYP1B1 enzymes are regulated by the aryl hydrocarbon receptor (AhR), a transcription factor activated by a variety of ligands among which Malassezia metabolites. In this study, we analyzed the modulation of CYP1A1, CYP1B1, and AhR in human keratinocytes infected with different strains of Malassezia pachydermatis, as well as the upregulation of some genes involved in the epidermal homeostasis. We demonstrated that all the strains induced AhR activation and its nuclear translocation in HaCaT cells infected for 24 h, compared to untreated cells. The expression of CYP1A1 and CYP1B1, prototypical markers of the AhR signaling pathway, were upregulated with the level of CYP1A1 mRNA approximately 100-fold greater than that for CYP1B1. Filaggrin, involucrin, and TGaseI, proteins involved in epidermal differentiation, were all modulated by Malassezia pachydermatis strains, with the strongest induction observed for filaggrin. By contrast, quinone oxidoreductase 1 (NQO1), which is part of the antioxidant defense system involved in detoxification, was not modulated in our experimental model. In conclusions, our findings suggest that Malassezia pachydermatis infection of human keratinocytes induces activation of the AhR, and increases the expression of its responsive genes and markers of epidermal differentiation, paving the way for occurrence/exacerbation of pathological skin conditions.

Correction to: Effect of 1064-nm Q-switched Nd:YAG laser on invasiveness and innate immune response in keratinocytes infected with Candida albicans.

In the published online version of the article, the authors' given and family names were incorrectly captured. The corrected names are shown in the author group section above.

Effect of 1064-nm Q-switched Nd:YAG laser on invasiveness and innate immune response in keratinocytes infected with Candida albicans.

Candida albicans is an opportunistic pathogen commensal in the oral cavity, vagina, and healthy skin. Common therapeutic options for fungal infections are topical or systemic antifungal drugs. Recently, in cutaneous pathologies, lasers and light-based treatments have emerged showing few contraindications and minimal side effects. The Q-switched (Nd-YAG) laser at a wavelength of 1064 nm has been shown to be useful in dermatology, dentistry, and some other medical specialties. It is used to treat onychomycoses, warts, and wounds and in some other treatments. We analyzed the effect of Q-switched (Nd-YAG) laser 1064 nm on human keratinocytes infected with C. albicans. In particular, we evaluated the effect of laser on invasiveness of C. albicans and on inflammatory and protective response of HaCaT cells infected. The results obtained did not show inhibitory, fungicidal, or fungistatic effects of laser on yeast; in addition, laser did not affect HaCaT vitality. HaCaT cells infected with C. albicans and irradiated with laser showed a reduction of invasiveness of TNF-α and IL8 gene expression and an increase of immunomodulatory cytokines such as TGFß. Furthermore, laser induces a significant over-expression of HSP70B (heat shock protein) and of HBD-2 (Human ß defensin-2) in HaCaT infected with C. albicans, compared to the untreated control. The use of Q-switched Nd:YAG laser in skin mycosis caused by C. albicans reduces yeast invasiveness in keratinocytes, downregulates inflammatory activities, and facilitates cytoprotection and antimicrobial defense. Our results offer a promising therapeutic strategy in the management of skin candidiasis, also in combination with conventional therapies.