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

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

Regulatory Ability of Lactiplantibacillus plantarum on Human Skin Health by Counteracting In Vitro Malassezia furfur Effects.

The skin serves as the first barrier against pathogen attacks, thanks to its multifunctional microbial community. Malassezia furfur is a commensal organism of normal cutaneous microflora but is also a cause of skin diseases. It acts on different cell pattern recognition receptors (TLRs, AhR, NLRP3 inflammasome) leading to cellular damage, barrier impairment, and inflammatory cytokines production. Lactobacillus spp. Is an endogenous inhabitant of healthy skin, and studies have proven its beneficial role in wound healing, skin inflammation, and protection against pathogen infections. The aim of our study is to demonstrate the ability of live Lactiplantibacillus plantarum to interfere with the harmful effects of the yeast on human keratinocytes (HaCat) in vitro. To enable this, the cells were treated with M. furfur, either alone or in the presence of L. plantarum. To study the inflammasome activation, cells require a stimulus triggering inflammation (LPS) before M. furfur infection, with or without L. plantarum. L. plantarum effectively counteracts all the harmful strategies of yeast, reducing the phospholipase activity, accelerating wound repair, restoring barrier integrity, reducing AhR and NLRP3 inflammasome activation, and, consequently, releasing inflammatory cytokines. Although lactobacilli have a long history of use in fermented foods, it can be speculated that they can also have health-promoting activities when topically applied.

Oreoch-1: A Peptide from Oreochromis niloticus as a Potential Tool against Staphylococci.

Staphylococci, including Staphylococcus aureus and Staphylococcus epidermidis, are important human pathogens associated with potentially life-threatening infections. Their great biofilm-producing ability and the development of resistance mechanisms often account for therapeutic failure. Hence, the scientific community has devoted intensive efforts to the development of antimicrobial compounds active against both planktonic and sessile bacterial populations. Contextually, antimicrobial peptides (AMPs) are natural peptides produced by the innate immunity of every organism, representing a potential new therapeutic solution against human microbial pathogens. Our work focused on the in vitro activity of Oreoch-1, an AMP from the gills of Nile tilapia (Oreochromis niloticus), against standard and clinical S. aureus and S. epidermidis strains. Firstly, the cytotoxicity profile of Oreoch-1 was determined in human colon carcinoma cells. Secondly, its antibacterial spectrum was explored against staphylococcal strains to set up the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC). Our results highlighted an antibacterial activity in the range 6.25-25 µM, with a general bacteriostatic effect. Therefore, the biofilm-inhibitory property was assessed against S. aureus ATCC 25923 and S. epidermidis ATCC 35984, indicating a significant reduction in S. aureus biomass at sub-MIC concentrations. Overall, our study indicates Oreoch-1 as a promising new therapeutic weapon against staphylococcal infections.

Evaluation of Different Activity of Lactobacillus spp. against Two Proteus mirabilis Isolated Clinical Strains in Different Anatomical Sites In Vitro: An Explorative Study to Improve the Therapeutic Approach.

Urinary tract infections (UTIs) and catheter-associated UTIs (CAUTIs) are the principal hospital-acquired infections. Between these, bacterial prostatitis is believed to be the leading cause of recurrent UTIs in men under 50 years of age and is often unresponsive to antibiotic treatment. Proteus mirabilis is more commonly associated with UTIs in these abnormalities, especially in patients undergoing catheterization. Lactobacillus spp. are an important component of the human microbiota and occur in large quantities in foods. Probiotics are proposed as an alternative to antibiotic therapy in the treatment of urinary tract infections. In addition to their ability to produce antimicrobial metabolites, they have immunomodulatory activity and do not cause side effects. For this reason, the combination of probiotic microorganisms and conventional drugs was considered. The aim of this work was to select the most active Lactobacillus strains against two clinical isolates of P. mirabilis on bladder and prostatic epithelium, potentially exploitable to improve the clinical management of UTIs.

An Unconventional Oral Candidiasis in an Immunocompetent Patient.

Oral candidiasis (OC) is an opportunistic fungal infection of the oral mucosae, sustained by Candida albicans or other non-albican Candida species (NAC), usually eradicated by conventional antifungals of the classes of azoles, polyenes, or derivative from echinocandins. OC usually occurs under predisposing local or systemic factors. C. lusitaniae is an opportunistic strain that is rarely responsible for human infection and occurs mainly in severe immunocompromised states. The present work reported an unconventional case of OC in an otherwise healthy immunocompetent woman sustained by C. lusitaniae and a multi-resistant strain of C. albicans.

In Vitro Evaluation of the Most Active Probiotic Strains Able to Improve the Intestinal Barrier Functions and to Prevent Inflammatory Diseases of the Gastrointestinal System.

Background: The integrity of the intestinal barrier is fundamental to gut health and homeostasis; its damage can increase intestinal permeability, with translocation of bacteria and/or endotoxins from gut, and the onset of various intestinal diseases. Lactobacillus spp. is one of the most common probiotics normally found in fermented foods and dairy products and is known for its anti-inflammatory and immunomodulatory properties and for its ability to protect and enhance the intestinal barrier functions. The aim of this work was to evaluate the ability of different strains of Lactobacillus spp. to improve in vitro the integrity of the intestinal barrier, to exert anti-inflammatory and immunomodulatory activity and to prevent Salmonella Typhimurium and enteroinvasive Escherichia coli (EIEC) infections. Methods: We analyzed the cellular expression of tight junctions, antimicrobial peptide HBD-2, pro-inflammatory cytokines and the inhibition of pathogens adhesion and invasion in a model of co-cultured epithelial cells treated with Lactobacillus spp. Results: L. brevis, L. reuteri and L. rhamnosus proved to be more effective in protecting the intestinal epithelium. Conclusions: These in vitro studies can help select strains particularly active in their intended use to obtain consortia formulations that can have as much maximum yield as possible in terms of patient benefit.

Antimicrobial peptide human ß-defensin-2 improves in vitro cellular viability and reduces pro-inflammatory effects induced by enteroinvasive Escherichia coli in Caco-2 cells by inhibiting invasion and virulence factors' expression.

Escherichia coli is one of the commensal species most represented in the intestinal microbiota. However, there are some strains that can acquire new virulence factors that enable them to adapt to new intestinal niches. These include enteroinvasive E. coli (EIEC) that is responsible for the bacillary dysentery that causes severe diarrheal symptoms in both children and adults. Due to the increasing onset of antibiotic resistance phenomena, scientific research is focused on the study of other therapeutic approaches for the treatment of bacterial infections. A promising alternative could be represented by antimicrobial peptides (AMPs), that have received widespread attention due to their broad antimicrobial spectrum and low incidence of bacterial resistance. AMPs modulate the immune defenses of the host and regulate the composition of microbiota and the renewal of the intestinal epithelium. With the aim to investigate an alternative therapeutic approach, especially in the case of antibiotic resistance, in this work we created a line of intestinal epithelial cells able to express high concentrations of AMP human ß-defensin-2 (HBD-2) in order to test its ability to interfere with the pathogenicity mechanisms of EIEC. The results showed that HBD-2 is able to significantly reduce the expression of the proinflammatory cytokines by intestinal epithelial cells, the invasiveness ability of EIEC and the expression of invasion-associated genes.

Decreased expression of Malassezia furfur virulence factors after Q-switched Nd:YAG laser irradiation.

Malassezia spp. are lipophilic yeasts implicated in the pathogenesis of chronic skin diseases. Repeated therapies are often necessary due to the recurrence of this type of disease. Recently, laser and light-based devices used for the treatment of some skin diseases have shown good efficacy, few contraindications, and minimal side effects. The neodymium-doped yttrium aluminium garnet (Q-switched Nd:YAG) laser is one of the most commonly used lasers in dermatology. The aim of this study was to evaluate the effect of the Q-switched Nd:YAG laser (Medlite C6 laser, Conbio, USA) on the pathogenic mechanisms of M. furfur during skin infections. Following laser exposure, the ability of M. furfur to retain phospholipase activity, upregulate the aryl receptor and its associated pathway, and stimulate the immune response were tested. The Q-switched Nd:YAG laser was shown to attenuate the virulence of M. furfur. The Q-switched Nd:YAG laser should be considered as a valid therapeutic alternative for the treatment of Malassezia-associated infections.

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

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

Lactobacillus brevis CD2: Fermentation Strategies and Extracellular Metabolites Characterization.

Functional foods and nutraceuticals frequently contain viable probiotic strains that, at certain titers, are considered to be responsible of beneficial effects on health. Recently, it was observed that secreted metabolites might play a key role in this respect, especially in immunomodulation. Exopolysaccharides produced by probiotics, for example, are used in the food, pharmaceutical, and biomedical fields, due to their unique properties. Lactobacillus brevis CD2 demonstrated the ability to inhibit oral pathogens causing mucositis and periodontal inflammation and to reduce Helycobacter pylori infections. Due to the lack of literature, for this strain, on the development of fermentation processes that can increase the titer of viable cells and associated metabolites to industrially attractive levels, different batch and fed-batch strategies were investigated in the present study. In particular, aeration was shown to improve the growth rate and the yields of lactic acid and biomass in batch cultures. The use of an exponential feeding profile in fed-batch experiments allowed to produce 9.3 ± 0.45 × 109 CFU/mL in 42 h of growth, corresponding to a 20-fold increase of viable cells compared with that obtained in aerated batch processes; moreover, also increased titers of exopolysaccharides and lactic acid (260 and 150%, respectively) were observed. A purification process based on ultrafiltration, charcoal treatment, and solvent precipitation was applied to partially purify secreted metabolites and separate them into two molecular weight fractions (above and below 10 kDa). Both fractions inhibited growth of the known gut pathogen, Salmonella typhimurium, demonstrating that lactic acid plays a major role in pathogen growth inhibition, which is however further enhanced by the presence of Lact. brevis CD2 exopolysaccharides. Finally, the EPS produced from Lact. brevis CD2 was characterized by NMR for the first time up to date.

Induction of Different Apoptosis Pathways by Two Proteus mirabilis Clinical Isolates Strains in Prostatic Epithelial Cells.

Bacterial prostatitis is believed to be the leading cause of recurrent urinary tract infections (UTIs) in men under 50 years of age and occurs both as an acute febrile disease responsive to antibiotics and as a chronic infection that is often unresponsive to antibiotic treatment. Proteus mirabilis is more commonly associated with UTIs in these abnormalities, especially in patients undergoing catheterisation. This pathogen is able to colonise the host's tissues and to cause disease thanks to the production of many virulence factors such as fimbriae, flagella, immune avoidance, host-damaging factors, and the ability to form crystalline biofilms. In addition, Proteus lipid A may exhibit apoptotic activity and induce desquamation of epithelial cells. The aim of this work was to evaluate the ability of two clinically isolated strains of P. mirabilis that are phenotypically different, named PM1 of PM2, respectively, to induce apoptosis in human prostatic adenocarcinoma PC-3. Our results demonstrate that PM1 and PM2 are able to activate two different apoptotic pathways, and this different behaviour is confirmed by the expression level of the ZapA gene, molecular fingerprinting and different spectrum of antibiotic resistance. The identification and knowledge of relations between the microorganism and host may provide the basis for new solutions to clinical problems with regard to diagnosis and therapy.

Beta-Defensin-2 and Beta-Defensin-3 Reduce Intestinal Damage Caused by Salmonella typhimurium Modulating the Expression of Cytokines and Enhancing the Probiotic Activity of Enterococcus faecium.

The intestinal microbiota is a major factor in human health and disease. This microbial community includes autochthonous (permanent inhabitants) and allochthonous (transient inhabitants) microorganisms that contribute to maintaining the integrity of the intestinal wall, modulating responses to pathogenic noxae and representing a key factor in the maturation of the immune system. If this healthy microbiota is disrupted by antibiotics, chemotherapy, or a change in diet, intestinal colonization by pathogenic bacteria or viruses may occur, leading to disease. To manage substantial microbial exposure, epithelial surfaces of the intestinal tract produce a diverse arsenal of antimicrobial peptides (AMPs), including, of considerable importance, the ß-defensins, which directly kill or inhibit the growth of microorganisms. Based on the literature data, the purpose of this work was to create a line of intestinal epithelial cells able to stably express gene encoding human ß-defensin-2 (hBD-2) and human ß-defensin-3 (hBD-3), in order to test their role in S. typhimurium infections and their interaction with the bacteria of the gut microbiota.

Biofilm Formation and Immunomodulatory Activity of Proteus mirabilis Clinically Isolated Strains.

Urinary tract infections (UTIs) and catheter-associated UTIs (CAUTIs) are the principal hospital-acquired infections. Proteus mirabilis is characterized by several virulence factors able to promote adhesion and biofilm formation and ameliorate the colonization of urinary tract and the formation of crystalline biofilms on the abiotic surface of the urinary catheters. Since, to date, the role of P. mirabilis in the etiopathogenesis of different types of urinary tract infections is not well established, in this study we sought to characterize two different clinically isolated strains of P. mirabilis (PM1 and PM2) with distinctive phenotypes and analyzed various virulence factors possibly implicated in the ability to induce UTIs and CAUTIs. In particular, we analyzed motility, biofilm formation both on abiotic and biotic surfaces of PM1 and PM2 and paralleled these parameters with the ability to induce an inflammatory response in an epithelial cell model. Results showed that PM1 displayed major motility and a capacity to form biofilm and was associated with an anti-inflammatory response of host cells. Conversely, PM2 exhibited lack motility and a had slower organization in biofilm but promoted an increase of proinflammatory cytokine expression in infected epithelial cells. Our study provides data useful to start uncovering the pathologic basis of P. mirabilis-associated urinary infections. The evidence of different virulence factors expressed by PM1 and PM2 highlights the possibility to use precise and personalized therapies targeting specific virulence pathways.