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Plant natural products offer promise in combating multi-drug resistance by acting as antibacterial agents through various mechanisms. A metabolomic-guided phytochemical investigation, based on a LC-HRMS/MS and Molecular Networking combined approach, was carried out on an extract of M. alba L. (mulberry) twigs, a common of byproduct of mulberry utilization. Molecular Networking uncovered different clusters of prenylated polyphenols, glycosylated phenolic compounds, and Diels-Alder dimers, steering the phytochemical profiling of this extract. This led to the swift annotation and subsequent isolation of 17 secondary metabolites including stilbenoids, flavonoids, and flavanones. Isolated metabolites were tested for their antimicrobial activity against Staphylococcus species. The most active compound resulted to be kuwanon C, exhibiting a MIC value of 8 μg/mL against the methicillin resistant S. aureus (MRSA) strain and a biofilm producer strain of S. epidermidis. We also observed an interaction between 4 μg/mL of kuwanon C in combination with low oxacillin dosage against the MRSA. Thanks to the high chemical structure similarity of isolated metabolites, structure-activity relationships of these versatile scaffolds have been postulated., Competing Interests: Declaration of competing interest The Authors declare no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

The widespread and irrational use of azole antifungal agents has led to an increase of azole-resistant Candida albicans strains with an urgent need for combination drug therapy, enhancing the treatment efficacy. Here, we report the discovery of a first-in-class pyrazole-isoxazole, namely, 5b , that showed remarkable growth inhibition against the C . albicans ATCC 10231 strain in combination with voriconazole, acting as a downregulator of ERG 11 ( Cyp51 ) gene expression with a significant reduction of the yeast-to-hypha morphological transition. Furthermore, C . albicans CYP51 enzyme assay and in-depth molecular docking studies unveiled the unique ability of the combination of 5b and voriconazole to completely fill the CYP51 binding sites. In vivo studies using a Galleria mellonella model confirmed the previously in vitro observed synergistic effect of 5b with voriconazole. Also considering its biocompatibility in a cellular model of human keratinocytes, these results indicate that 5b represents a promising compound for a further optimization campaign.

The Aryl hydrocarbon receptor (AHR) is a cytosolic receptor and ligand-activated transcription factor widely expressed across various cell types in the body. Its signaling is vital for host responses at barrier sites, regulating epithelial renewal, barrier integrity, and the activities of several types of immune cells. This makes AHR essential for various cellular responses during aging, especially those governing inflammation and immunity. In this review, we provided an overview of the mechanisms by which the AHR mediates inflammatory response at gut and brain level through signals from intestinal microbes. The age-related reduction of gut microbiota functions is perceived as a trigger of aberrant immune responses linking gut and brain inflammation to neurodegeneration. Thus, we explored gut microbiome impact on the nature and availability of AHR ligands and outcomes for several signaling pathways involved in neurodegenerative diseases and age-associated decline of brain functions, with an insight on Parkinson's and Alzheimer's diseases, the most common neurodegenerative diseases in the elderly. Specifically, we focused on microbial tryptophan catabolism responsible for the production of several AHR ligands. Perspectives for the development of microbiota-based interventions targeting AHR activity are presented for a healthy aging., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Coretti, Buommino and Lembo.)

Bacterial infections represent a key public health issue due to the occurrence of multidrug-resistant bacteria. Recently, the amount of data supporting the dynamic control of epigenetic pathways by environmental cues has triggered research efforts toward the clarification of their role in microbial infections. Among protein post-translational modifications, reversible acetylation is the most implicated in the feedback to environmental stimuli and in cellular homeostasis. Accordingly, the latest studies identified the histone deacetylase 6 (HDAC6) enzyme as a crucial player in the complex molecular machinery underlying bacterial clearance or killing. A very important milestone for the elucidation of the consequence of HDAC6 activity in bacterial infections is herein described, unveiling for the first time the role of a potent HDAC6 inhibitor in interfering with biofilm formation and modulating virulence factors of P. aeruginosa . We demonstrated that compound F2F-2020202 affected the production of some important virulence factors in P. aeruginosa , namely pyocyanin and rhamnolipids, clearly impairing its ability to form biofilm. Furthermore, evidence of possible QS involvement is supported by differential regulation of specific genes, namely RhlI, phAz1, and qsrO. The data herein obtained also complement and in part explain our previous results with selective HDAC6 inhibitors able to reduce inflammation and bacterial load in chronic infection models recapitulating the cystic fibrosis (CF) phenotype. This study fosters future in-depth investigation to allow the complete elucidation of the molecular mechanisms underlying HDAC6's role in bacterial infections., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Barone, Mateu, Turco, Pelliccia, Lembo, Summa, Buommino and Brindisi.)

The occurrence of increased antibiotic resistance has reduced the availability of drugs effective in the control of infectious diseases, especially those caused by various combinations of bacteria and/or fungi that are often associated with poorer patient outcomes. In the hunt for novel antibiotics of interest to treat polymicrobial diseases, molecules bearing guanidine moieties have recently come to the fore in designing and optimizing antimicrobial agents. Due to their remarkable antibacterial and antifungal activities, labdane diterpenes are also attracting increasing interest in antimicrobial drug discovery. In this study, six different guanidines prenylated with labdanic fragments were synthesized and evaluated for their antimicrobial properties. Assays were carried out against both non-resistant and antibiotic-resistant bacteria strains, while their possible antifungal activities have been tested on the yeast Candida albicans. Two of the synthesized compounds, namely labdan-8,13(R)-epoxy-15-oyl guanidine and labdan-8,13(S)-epoxy-15-oyl guanidine, were finally selected as the best candidates for further developments in drug discovery, due to their antimicrobial effects on both Gram-negative and Gram-positive bacterial strains, their fungicide action, and their moderate toxicity in vivo on zebrafish embryos. The study also provides insights into the structure-activity relationships of the guanidine-functionalized labdane-type diterpenoids., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

The increasing resistance of fungi to conventional antifungal drugs has prompted worldwide the search for new compounds. In this work, we investigated the antifungal properties of acylated Temporin L derivatives, Pent-1B and Dec-1B , against Candida albicans , including the multidrug-resistant strains. Acylated peptides resulted to be active both on reference and clinical strains with MIC values ranging from 6.5 to 26 µM, and they did not show cytotoxicity on human keratinocytes. In addition, we also observed a synergistic or additive effect with voriconazole for peptides Dec-1B and Pent-1B through the checkerboard assay on voriconazole-resistant Candida strains. Moreover, fluorescence-based assays, NMR spectroscopy, and confocal microscopy elucidated a potential membrane-active mechanism, consisting of an initial electrostatic interaction of acylated peptides with fungal membrane, followed by aggregation and insertion into the lipid bilayer and causing membrane perturbation probably through a carpeting effect.

Diverse natural and synthetic furan derivatives have shown biological activity. Here, we describe the preparation of benzyl and arylethyl β-furanamides with OH or OMe aryl substituents by an adapted sustainable method from a furoic acid using methyl chloroformate. Symmetric and asymmetric β,β'-furanamides have instead been prepared using azabenzotriazole based catalyst (HATU). The products have been evaluated for their antimicrobial properties on Gram positive and Gram negative bacteria. Just a minimal not-significant activity has been observed in some derivatives.

Gut dysbiosis has been involved in the pathogenesis and progression of Parkinson's disease (PD), but the mechanisms through which gut microbiota (GM) exerts its influences deserve further study. Recently, we proposed a two-hit mouse model of PD in which ceftriaxone (CFX)-induced dysbiosis amplifies the neurodegenerative phenotype generated by striatal 6-hydroxydopamine (6-OHDA) injection in mice. Low GM diversity and the depletion of key gut colonizers and butyrate producers were the main signatures of GM alteration in this model. Here, we used the phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt2) to unravel candidate pathways of cell-to-cell communication associated with dual-hit mice and potentially involved in PD progression. We focused our analysis on short-chain fatty acids (SCFAs) metabolism and quorum sensing (QS) signaling. Based on linear discriminant analysis, combined with the effect size results, we found increased functions linked to pyruvate utilization and a depletion of acetate and butyrate production in 6-OHDA+CFX mice. The specific arrangement of QS signaling as a possible result of the disrupted GM structure was also observed. With this exploratory study, we suggested a scenario in which SCFAs metabolism and QS signaling might represent the effectors of gut dysbiosis potentially involved in the designation of the functional outcomes that contribute to the exacerbation of the neurodegenerative phenotype in the dual-hit animal model of PD.

The [1,2,3]-triazolo [1,5-a] quinoxalin-4(5 H )-one scaffold and its analogues triazole-fused heterocyclic compounds are relevant structural templates in both natural and synthetic biologically active compounds. However, their medicinal chemistry applications are often limited due to the lack of synthetic protocols combining straightforward generation of the central core while also allowing extensive decoration activity for drug discovery purposes. Herein, we report a "refreshed" synthesis of the [1,2,3]-triazolo [1,5- a ]quinoxalin-4(5 H )-one core, encompassing the use of eco-compatible catalysts and reaction conditions. We have also performed a sustainable and extensive derivatization campaign at both the endocyclic amide nitrogen and the ester functionality, comprehensively exploring the reaction scope and overcoming some of the previously reported difficulties in introducing functional groups on this structural template. Finally, we unveiled a preliminary biological investigation for the newly generated chemical entities. Our assessment of the compounds on different bacterial species (two S. aureus strains, three P. aeruginosa strains, K. pneumonia ), and two fungal C. albicans strains, as well as the evaluation of their activity on S. epidermidis biofilm formation, foster further optimization for the retrieved hit compounds 9 , 14 , and 20 ., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Pelliccia, Alfano, Gomes Da Assunção, Turco, Lembo, Summa, Buommino and Brindisi.)

Species of Myrtaceae Juss., the ninth largest family of flowering plants, are a valuable source of bioactive specialized metabolites. A leading position belongs to phloroglucinol derivatives, thanks to their unusual structural features and biological and pharmacological properties. Myrcianthes cisplatensis (Cambess.) O. Berg, a common tree on the banks of rivers and streams of Uruguay, southern Brazil, and northern Argentina, with aromatic leaves, is known as a diuretic, febrifuge, tonic, and good remedy for lung and bronchial diseases. Despite knowledge about traditional use, few data on its phytochemical properties have been reported in the literature. The methanol extract of M. cisplatensis , grown in Arizona, USA, was first partitioned between dichloromethane and water and then with ethyl acetate. The enriched fractions were evaluated using a broth microdilution assay against Staphylococcus aureus ATCC 29213 and 43300 (methicillin-resistant S. aureus (MRSA)). The potential antimicrobial activity seemed to increase in the dichloromethane extract, with a MIC value of 16 µg/mL against both strains. Following a bio-guided approach, chromatographic techniques allowed for isolating three coumarin derivatives, namely endoperoxide G3, catechin, and quercitrin, and four new p -coumaroyl alkylphloroglucinol glucosides, named p -coumaroylmyrciacommulone A-D. Their structures were characterized through spectroscopic techniques: 2D-NMR experiments (HSQC, HMBC, and HSQC-TOCSY) and spectrometric analyses (HR-MS). The antimicrobial assessment of pure compounds against S. aureus ATCC 29213 and ATCC 43300 demonstrated the best activity for p -coumaroylmyrciacommulone C and D with the growth inhibition of 50% at 32 µg/mL against both strains of S. aureus .

Myrtaceae family is a continuous source of antimicrobial agents. In the search for novel antimicrobial agents against Staphylococcus species, bioactive fractions of Myrtus communis L., growing in the Sardinia island (Italy) have been investigated. Their phytochemical analysis led us to isolate and characterize four alkylphloroglucinol glycosides ( 1 - 4 ), three of them gallomyrtucommulones G-H ( 1 , 2 ), and myrtucommulonoside ( 4 ) isolated and characterized for the first time. The structures of the new and known compounds, endopreroxide G3 ( 5 ), myricetin-3- O -glycosides ( 6 , 7 ) were determined based on the spectroscopic evidence including 1D-/2D-NMR and HR-MS spectrometry. Enriched fractions as well as pure compounds were tested for their antimicrobial activity by broth micro-dilution assay against Staphylococcus epidermidis and S. aureus. Results reported herein demonstrated that gallomyrtucommulone G ( 1 ) showed a selective antimicrobial activity against both S. aureus strains (ATCC 29213 and 43300) until 16 μg/mL while gallomyrtucommulone D ( 3 ) showed the best growth inhibition value at 64 μg/mL.

Temporin family is one of the largest among antimicrobial peptides (AMPs), which act mainly by penetrating and disrupting the bacterial membranes. To further understand the relationship between the physical-chemical properties and their antimicrobial activity and selectivity, an analogue of Temporin L, [Nle 1 , dLeu 9 , dLys 10 ]TL (Nle-Phe-Val-Pro-Trp-Phe-Lys-Phe-dLeu-dLys-Arg-Ile-Leu-CONH 2 ) has been developed in the present work. The design strategy consisted of the addition of a norleucine residue at the N-terminus of the lead peptide sequence, [dLeu 9 , dLys 10 ]TL, previously developed by our group. This modification promoted an increase of peptide hydrophobicity and, interestingly, more efficient activity against both Gram-positive and Gram-negative strains, without affecting human keratinocytes and red blood cells survival compared to the lead peptide. Thus, this novel compound was subjected to biophysical studies, which showed that the peptide [Nle 1 , dLeu 9 , dLys 10 ]TL is unstructured in water, while it adopts β-type conformation in liposomes mimicking bacterial membranes, in contrast to its lead peptide forming α-helical aggregates. After its aggregation in the bacterial membrane, [Nle 1 , dLeu 9 , dLys 10 ]TL induced membrane destabilization and deformation. In addition, the increase of peptide hydrophobicity did not cause a loss of anti-inflammatory activity of the peptide [Nle 1 , dLeu 9 , dLys 10 ]TL in comparison with its lead peptide. In this study, our results demonstrated that positive net charge, optimum hydrophobic-hydrophilic balance, and chain length remain the most important parameters to be addressed while designing small cationic AMPs.

The generation of peptidomimetic substructures for medicinal chemistry purposes requires effective and divergent synthetic methods. We present in this work an efficient flow process that allows quick modulation of reagents for Joullié-Ugi multicomponent reaction, using spiroindolenines as core motifs. This sterically hindered imine equivalent could successfully be diversified using various isocyanides and amino acids in generally good space-time yields. A telescoped flow process combining interrupted Fischer reaction for spiroindolenine synthesis and subsequent Joullié-Ugi-type modification resulted in product formation in very good overall yield in less than 2 hours compared to 48 hours required in batch mode. The developed protocol can be seen as a general tool for rapid and facile generation of peptidomimetic compounds. We also showcase preliminary biological assessments for the prepared compounds., (© 2021 The Authors. ChemMedChem published by Wiley-VCH GmbH.)

Over the years, the increasing acquisition of antibiotic resistance genes has led to the emergence of highly resistant bacterial strains and the loss of standard antibiotics' efficacy, including β-lactam/β-lactamase inhibitor combinations and the last line carbapenems. Klebsiella pneumoniae is considered one of the major exponents of a group of multidrug-resistant ESKAPE pathogens responsible for serious healthcare-associated infections. In this study, we proved the antimicrobial activity of two analogues of Temporin L against twenty carbapenemase-producing K. pneumoniae clinical isolates. According to the antibiotic susceptibility assay, all the K. pneumoniae strains were resistant to at least one other class of antibiotics, in addition to beta-lactams. Peptides 1B and C showed activity on all test strains, but the lipidated analogue C expressed the greater antimicrobial properties, with MIC values ranging from 6.25 to 25 µM. Furthermore, the peptide C showed bactericidal activity at MIC values. The results clearly highlight the great potential of antimicrobial peptides both as a new treatment option for difficult-to-treat infections and as a new strategy of drug-resistance control.

Staphylococcus aureus is an important opportunistic pathogen that causes many infections in humans and animals. The inappropriate use of antibiotics has favored the diffusion of methicillin-resistant S. aureus ( MRSA), nullifying the efforts undertaken in the discovery of antimicrobial agents. Oxadiazole heterocycles represent privileged scaffolds for the development of new drugs because of their unique bioisosteric properties, easy synthesis, and therapeutic potential. A vast number of oxadiazole-containing derivatives have been discovered as potent antibacterial agents against multidrug-resistant MRSA strains. Here, we investigate the ability of a new library of oxadiazoles to contrast the growth of Gram-positive and Gram-negative strains. The strongest antimicrobial activity was obtained with compounds 3 (4 µM) and 12 (2 µM). Compound 12 , selected for further evaluation, was found to be noncytotoxic on the HaCaT cell line up to 25 µM, bactericidal, and was able to improve the activity of oxacillin against the MRSA. The highest synergistic interaction was obtained with the combination values of 0.78 μM for compound 12, and 0.06 μg/mL for oxacillin. The FIC index value of 0.396 confirms the synergistic effect of compound 12 and oxacillin. MRSA treatment with compound 12 reduced the expression of genes included in the mec operon. In conclusion, 12 inhibited the growth of the MRSA and restored the activity of oxacillin, thus resulting in a promising compound in the treatment of MRSA infection.

The pharmacodynamic and pharmacokinetic properties of bioactive peptides can be modulated by introducing conformational constraints such as intramolecular macrocyclizations, which can involve either the backbone and/or side chains. Herein, we aimed at increasing the α-helicity content of temporin L, an isoform of an intriguing class of linear antimicrobial peptides (AMPs), endowed with a wide antimicrobial spectrum, by the employment of diverse side-chain tethering strategies, including lactam, 1,4-substituted [1,2,3]-triazole, hydrocarbon, and disulfide linkers. Our approach resulted in a library of cyclic temporin L analogues that were biologically assessed for their antimicrobial, cytotoxic, and antibiofilm activities, leading to the development of the first-in-class cyclic peptide related to this AMP family. Our results allowed us to expand the knowledge regarding the relationship between the α-helical character of temporin derivatives and their biological activity, paving the way for the development of improved antibiotic cyclic AMP analogues.

Objective: A large number of studies have highlighted the important role of the gut microbiota in the pathophysiology of neurological disorders, suggesting that its manipulation might serve as a treatment strategy. We hypothesized that the gut microbiota participates in absence seizure development and maintenance in the WAG/Rij rat model and tested this hypothesis by evaluating potential gut microbiota and intestinal alterations in the model, as well as measuring the impact of microbiota manipulation using fecal microbiota transplantation (FMT)., Methods: Initially, gut microbiota composition and intestinal histology of WAG/Rij rats (a well-recognized genetic model of absence epilepsy) were studied at 1, 4, and 8 months of age in comparison to nonepileptic Wistar rats. Subsequently, in a second set of experiments, at 6 months of age, untreated Wistar or WAG/Rij rats treated with ethosuximide (ETH) were used as gut microbiota donors for FMT in WAG/Rij rats, and electroencephalographic (EEG) recordings were obtained over 4 weeks. At the end of FMT, stool and gut samples were collected, absence seizures were measured on EEG recordings, and microbiota analysis and histopathological examinations were performed., Results: Gut microbiota analysis showed differences in beta diversity and specific phylotypes at all ages considered and significant variances in the Bacteroidetes/Firmicutes ratio between Wistar and WAG/Rij rats. FMT, from both Wistar and ETH-treated WAG/Rij donors to WAG/Rij rats, significantly decreased the number and duration of seizures. Histological results indicated that WAG/Rij rats were characterized by intestinal villi disruption and inflammatory infiltrates already at 1 month of age, before seizure occurrence; FMT partially restored intestinal morphology while also significantly modifying gut microbiota and concomitantly reducing absence seizures., Significance: Our results demonstrate for the first time that the gut microbiota is modified and contributes to seizure occurrence in a genetic animal model of absence epilepsy and that its manipulation may be a suitable therapeutic target for absence seizure management., (© 2021 International League Against Epilepsy.)

Resin acids are valued in traditional medicine for their antiseptic properties. Among these, abietic acid has been reported to be active against methicillin-resistant Staphylococcus aureus (MRSA) strains. In veterinary healthcare, the methicillin-resistant Staphylococcus pseudintermedius (MRSP) strain is an important reservoir of antibiotic resistance genes including mecA . The incidence of MRSP has been increasing, and treatment options in veterinary medicine are partial. Here, we investigated the antimicrobial and antibiofilm properties of abietic acid against three MRSP and two methicillin-susceptible Staphylococcus pseudintermedius (MSSP) strains, isolated from diseased pet animals and human wound samples. Abietic acid showed a significant minimal inhibitory concentration (MIC) value ranging from 32 to 64 μg/mL (MRSPs) and 8 μg/mL (MSSP). By checkerboard method we demonstrated that abietic acid increased oxacillin susceptibility of MRSP strains, thus showing a synergistic interaction with oxacillin. Abietic acid was also able to contrast the vitality of treated MSSP and MRSP1 biofilms at 20 μg/mL and 40 μg/mL, respectively. Finally, the compound moderately reduced mecA , mecR1 and mec1 gene expression. In conclusion, the results here reported demonstrate the antimicrobial activity of abietic acid against MRSP and support the use of this compound as a potential therapeutic agent to be used in combinatorial antibiotic therapy.

The rapid development of antimicrobial resistance is pushing the search in the discovering of novel antimicrobial molecules to prevent and treat bacterial infections. Self-assembling antimicrobial peptides, as the lipidated peptides, are a novel and promising class of molecules capable of meeting this need. Based on previous work on Temporin L analogs, several new molecules lipidated at the N- or and the C-terminus were synthesised. Our goal is to improve membrane interactions through finely tuning self-assembly to reduce oligomerisation in aqueous solution and enhance self-assembly in bacterial membranes while reducing toxicity against human cells. The results here reported show that the length of the aliphatic moiety is a key factor to control target cell specificity and the oligomeric state of peptides either in aqueous solution or in a membrane-mimicking environment. The results of this study pave the way for the design of novel molecules with enhanced activities.

Bacteria are social organisms able to build complex structures, such as biofilms, that are highly organized surface-associated communities of microorganisms, encased within a self- produced extracellular matrix. Biofilm is commonly associated with many health problems since its formation increases resistance to antibiotics and antimicrobial agents, as in the case of Pseudomonas aeruginosa and Staphylococcus aureus , two human pathogens causing major concern. P. aeruginosa is responsible for severe nosocomial infections, the most frequent of which is ventilator-associated pneumonia, while S. aureus causes several problems, like skin infections, septic arthritis, and endocarditis, to name just a few. Literature data suggest that natural products from plants, bacteria, fungi, and marine organisms have proven to be effective as anti-biofilm agents, inhibiting the formation of the polymer matrix, suppressing cell adhesion and attachment, and decreasing the virulence factors' production, thereby blocking the quorum sensing network. Here, we focus on plant derived chemicals, and provide an updated literature review on the anti-biofilm properties of terpenes, flavonoids, alkaloids, and phenolic compounds. Moreover, whenever information is available, we also report the mechanisms of action.

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 BF 3 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., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Interkingdom polymicrobial diseases are caused by different microorganisms that colonize the same niche, as in the case of yeast-bacteria coinfections. The latter are difficult to treat due the absence of any common therapeutic target for their elimination, both in animals and humans. Staphylococcus pseudintermedius and Malassezia pachydermatis belong to distinct kingdoms. They can colonize the same skin district or apparatus being the causative agents of fastidious pet animals' pathologies. Here we analysed the antimicrobial properties of a panel of 11 peptides, derived from temporin L, against Malassezia pachydermatis. Only peptide 8 showed the best mycocidal activity at 6.25 μM. Prolonged application of peptide 8 did not cause M. pachydermatis drug-resistance. Peptide 8 was also able to inhibit the growth of Staphylococcus pseudintermedius , regardless of methicillin resistance, at 1.56 μM for methicillin-susceptible S. pseudintermedius (MSSP) and 6.25 μM for methicillin-resistant S. pseudintermedius (MRSP). Of interest, peptide 8 increased the susceptibility of MRSP to oxacillin. Oxacillin MIC value reduction was of about eight times when used in combination with peptide 8 . Finally, the compound affected the vitality of bacteria embedded in S. pseudintermedius biofilm. In conclusion, peptide 8 might represent a valid therapeutic alternative in the treatment of interkingdom polymicrobial infections, also in the presence of methicillin-resistant bacteria.

Furolignan-type natural products, possessing important biological properties, have been synthesized from a commercially available furan. The elaborated synthetic strategy is based on an innovative Friedel-Crafts reaction starting from an alcohol or a carboxylic acid and triflic anhydride as promoter. Through this synthetic strategy, furolignans having two different aryl groups have been obtained. The products have been evaluated for their antimicrobial properties on Gram positive and Gram negative bacteria, in order to compare their biological activities with those of natural analogues.

Previously, we identified a potent antimicrobial analogue of temporin L (TL), [Pro 3 ]TL, in which glutamine at position 3 was substituted with proline. In this study, a series of analogues in which position 3 is substituted with non-natural proline derivatives, was investigated for correlations between the conformational properties of the compounds and their antibacterial, cytotoxic, and hemolytic activities. Non-natural proline analogues with substituents at position 4 of the pyrrolidine ring were considered. Structure-activity relationship (SAR) studies of these analogues were performed by means of antimicrobial and cytotoxicity assays along with circular dichroism (CD) and NMR spectroscopic analyses for selected compounds. The most promising peptides were additionally evaluated for their activity against some representative veterinary microbial strains to compare with those from human strains. We identified novel analogues with interesting properties that make them attractive lead compounds., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

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.

Proliferation and/or depletion of clusters of specific bacteria regulate intestinal functions and may interfere with neuro-immune communication and behavior in patients with autism spectrum disorder (ASD). Consistently, qualitative and quantitative alteration of bacterial metabolites may functionally affect ASD pathophysiology. Up to date, age-restricted cohort studies, that may potentially help to identify specific microbial signatures in ASD, are lacking. We investigated the gut microbiota (GM) structure and fecal short chain fatty acids (SCFAs) levels in a cohort of young children (2-4 years of age) with ASD, with respect to age-matched neurotypical healthy controls. Strong increase of Bacteroidetes and Proteobacteria and decrease of Actinobacteria was observed in these patients. Among the 91 OTUs whose relative abundance was altered in ASD patients, we observed a striking depletion of Bifidobacterium longum , one of the dominant bacteria in infant GM and, conversely, an increase of Faecalibacterium prausnitzii , a late colonizer of healthy human gut and a major butyrate producer. High levels of F. prausnitzii were associated to increase of fecal butyrate levels within normal range, and over representation of KEGG functions related to butyrate production in ASD patients. Here we report unbalance of GM structure with a shift in colonization by gut beneficial bacterial species in ASD patients as off early childhood.

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 TGFβ. Furthermore, laser induces a significant over-expression of HSP70B (heat shock protein) and of HBD-2 (Human β 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.

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.

Naturally derived compounds represent a potential source of pharmacologically active drugs able to contrast different diseases, including gastric cancer, a multifactorial disease, in which the important role played by H. pylori infection has been demonstrated. Carexanes, stilbene derivatives, isolated from plants of the Carex distachya Desf., are unusual secondary metabolites with a tetracyclic skeleton arising from a cyclization of prenylstilbenoid precursors. In this study we firstly showed the ability of three purified carexanes CxB, CxG, and CxI to enhance the antioxidant response of AGS cells and to contrast the effect of the H. pylori's protein HspB. Among them CxI was the molecule that best modified the expression of genes involved in the antioxidant response. In particular, CxI was able to reduce Keap-1 gene expression and induce NQO1 gene expression, both at 4 and 24 h in AGS cells, as showed by real time PCR. Nrf2 induction was evident only at 24 h. Interestingly, the effect of CxI was stronger in HspB-transfected AGS cells, where Keap-1 gene expression was nearly abrogated. Finally, we demonstrated that CxI was able to reduce also COX-2 gene expression in HspB-transfected AGS cells, compared with untreated HspB-transfected cells, both at 4 and 24 h. This study first report that carexanes might represent candidate molecules able to contrast the deleterious effect of HspB protein but also to reduce the inflammatory process induced by H. pylori infection., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

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.

Three unusual amino-phloroglucinols, named helichrytalicines A-C, along with seventeen known compounds including acetophenones, tremetrone derivatives, low-molecular weight phenols, flavonol glucosides, have been isolated from the medium-polar extract of Helichrysum italicum (Roth) G. Don, a medicinal plant typical of the Mediterranean vegetation. The structures of the compounds have been elucidated based on extensive 2D-NMR spectroscopic analyses, including COSY, TOCSY, HSQC, CIGAR-HMBC, H2BC and HSQC-TOCSY, along with Q-TOF HRMS 2 analysis. Stereostructure of the new compounds has been elucidated by Mosher's method and NOESY experiment. Antimicrobial properties against Staphylococcus epidermidis of selected compounds have been evaluated., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Malassezia pachydermatis is a yeast belonging to the microbiota of the skin and mucous membranes of dog and cat, but it can also act as pathogen, causing dermatitis. The aim of this work was to evaluate the genetic variability of M. pachydermatis strains isolated from symptomatic dogs and cats and determine a correlation between genotype and phenotype. For this purpose eleven strains of M. pachydermatis were molecularly classified by nested-polymerase chain reaction (nested-PCR) based on ITS-1 and ITS-2 regions, specific for fungal rRNA genes. Furthermore, random amplification of polymorphic DNA (RAPD) was applied for genetic typing of M. pachydermatis isolates identifying four different genotypes. Strains belonging to genotype 1 produced the highest amount of biofilm and phospholipase activity. The inflammatory response induced by M. pachydermatis strains in immortalized human keratinocytes (HaCat cells) was significantly different when we compared the results obtained from each strain. In particular, HaCat cells infected with the strains belonging to genotypes 1 and 2 triggered the highest levels of increase in TLR-2, IL-1β, IL-6, IL-8, COX-2 and MMP-9 expression. By contrast, cells infected with the strains of genotype 3 and those of genotype 4 did not significantly induce TLR-2 and cytokines. The results obtained might suggest a possible association between genotype and virulence factors expressed by M. pachydermatis strains. This highlights the need for a more accurate identification of the yeast to improve the therapeutic approach and to monitor the onset of human infections caused by this emergent zoonotic pathogen.

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 increase in the resistance of bacteria to conventional antibiotics and the need for new antibiotics has stimulated interest in the use of AMPs as new therapeutic agents. The inducible nature of human defensin genes suggests that it is possible to increase the endogenous production by utilizing small molecules of various origins to enhance, even selectively, the expression of these peptides. In the light of their role in immunomodulation, angiogenesis, wound healing, inflammation and cancer, as well as their antimicrobial activity, it is possible induce their expression or create analogs with increased specific activity or various degrees of selectivity, or obtain human defensins with genetic engineering to optimize the potency and safety in order to reduce cytotoxicity and potential proinflammatory activity and susceptibility to protease and salt. Restoring the balance between immunostimulating and immunosuppressive molecules may be an important strategy to correct expression defects in specific diseases.

Chlamydia trachomatis, a human pathogen, is a Gram-negative bacillus and a compulsory intracellular parasite. It is the most common cause of bacterial sexually transmitted infections in both industrialized and developing countries. In women, untreated genital infections can result in devastating consequences such as pelvic inflammatory disease, ectopic pregnancy, and even infertility. Lactobacillus crispatus is an important urogenital species that is routinely found in the vagina of healthy women. Lactobacilli are involved in the maintenance of the normal vaginal microbiota and their dominance in the vagina suggests that they play a crucial role in protecting the genitourinary tract against pathological conditions. Lactobacilli can act through the activation of the immune system, but C. trachomatis is able to effectively evade immune surveillance in some individuals. The aim of our study was to investigate the immunomodulatory efficacy of the potential probiotic strain L. crispatus in HeLa and J774 cells subjected to C. trachomatis infection by studying the expression of the inflammatory cytokines IL-6, IL-8, TNF-α and IL-10. Our results demonstrated, firstly, the lack of any cytotoxic effect on the epithelial cells and macrophages when treated with L. crispatus and its supernatant; in addition, L. crispatus and its supernatant inhibited C. trachomatis adhesion and infectivity in human epithelial cells and macrophages. Our study then showed that L. crispatus and its supernatant reduced IL-6, IL-8 and TNF-α production in C. trachomatis-infected HeLa and J774 cells. In contrast, a significant upregulation of the IL-10 expression in HeLa and J774 cells by L. crispatus and supernatant was also demonstrated. Our data indicate that L. crispatus specifically enhances the production of the IL-10 anti-inflammatory cytokine in contrast to the inhibitory effect of L. crispatus on the pro-inflammatory cytokines., (Copyright © 2015. Published by Elsevier GmbH.)

Malassezia pachydermatis is part of the normal cutaneous microbiota of most warm-blooded vertebrates and is associated with otitis externa and seborrhoeic dermatitis in dogs and cats. In this study, we evaluated the growth capacity of nine M. pachydermatis strains on Sabouraud medium in the presence of a high concentration of gentamicin. Strains of M. pachydermatis cultured on Sabouraud medium in the presence of 50 and 100 µg gentamicin ml(-1) displayed different growth patterns such as growth or lack of growth. We hypothesized that this difference in growth of M. pachydermatis strains was correlated with the different genotypes of the strains. Random amplification of polymorphic DNA (RAPD) was applied for genetic typing of M. pachydermatis isolates, derived from the external ears of house pet cats suffering from otitis externa. The M. pachydermatis strains were cultured on commercial or home-made Sabouraud medium supplemented or not with gentamicin. RAPD analysis demonstrated a genetic heterogeneity between each strain. In particular, five out of nine strains tested were able to form colonies in the presence of gentamicin. However, a correlation between M. pachydermatis genotype and growth capacity in the presence of gentamicin was not widely demonstrated., (© 2015 The Authors.)

Knowledge in viral oncology has made considerable progress in the field of cancer fight. However, the role of bacteria as mediators of oncogenesis has not yet been elucidated. As cancer still is the leading cause of death in developed countries, understanding the long-term effects of bacteria has become of great importance as a possible means of cancer prevention. This study reports that Chlamydia pneumoniae infection induces transformation of human mesothelial cells. Mes1 cells infected with C. pneumoniae at a multiplicity of infection of 4 inclusion-forming units/cell showed many intracellular inclusion bodies. After a 7-day infection an increased proliferative activity was also observed. Real-time PCR analysis revealed a strong induction of calretinin, Wilms' tumour gene 1, osteopontin, matrix metalloproteinases-2, and membrane-type 1 metalloproteinases gene expression in Mes1 cell, infected for a longer period (14 days). The results were confirmed by western blot analysis. Zymography analysis showed that C. pneumoniae modulated the in-vitro secretion of MMP-2 in Mes1 cells both at 7 and 14 days. Cell invasion, as measured by matrigel-coated filter, increased after 7 and 14 days infection with C. pneumoniae, compared with uninfected Mes1 cells. The results of this study suggest that C. pneumoniae infection might support cellular transformation, thus increasing lung cancer risk., (Copyright© by the Spanish Society for Microbiology and Institute for Catalan Studies.)

Lymphedematous areas are sites of regional immune destabilization depicting a typical example of an immunocompromised cutaneous district (ICD). This study evaluates the expression of some components of the skin innate immunity on lymphedematous limbs with the aim to clarify some facets of the ICD. Patients selected underwent two skin biopsies: One was obtained from the limb affected by lymphedema, another from the contralateral healthy limb. Expression of some components of the skin innate immunity was analyzed by reverse transcription-polymerase chain reaction. Stronger gene expression of Toll-like receptor 2 (TLR-2), human β-defensin 2 (HBD-2), desmoglein 1, desmoglein 3, matrix metallopeptidase 9 (MMP-9), and interleukin 10 (IL-10) was found in keratinocytes derived from the affected limb compared with that of keratinocytes derived from contralateral healthy limb. Downregulation of survivin and vasoactive intestinal polypeptide (VIP) gene expression was found in the affected limbs. No induction of IL-1α and tumor necrosis factor α (TNF-α) was detectable in keratinocyte cultures obtained from both lymphedematous and normal limbs. Different phases and components of skin innate immunity turned out to be altered in the lymphedematous sites. Molecular alterations were similar in all patients recruited in the study. These changes might favor the local appearance or progression of opportunistic diseases such as tumors, infections, and immune-mediated skin disorders., (Copyright © 2014. Published by Elsevier Inc.)

Interaction of pathogenic bacteria with human cells is usually an essential step in the infection process. The bacterial invasion is stimulated by microbial binding to mammalian extracellular matrix proteins such as vitronectin, fibronectin or integrins. We have recently shown that some strains isolated from a clinical environment are able to grow at/or above 37°C. In particular, we demonstrated that P. fluorescens AF181 binds specifically to the surface of A549 human respiratory epithelial cells and that adhesiveness modulates the inflammatory response. In this study, the involvement of Alpha(v)Beta5 integrins and its respective natural ligand vitronectin (VN) in P. fluorescens AF181 adherence and invasion was examined. The host cell cytoskeleton and cellular tyrosine kinases seem to be solicited during the P. fluorescens-respiratory cell interaction; consequently, cytochalasin D and genistein decreased the bacterial adherence and internalization. Gene silencing of α(v), β5 integrins and vitronectin reduced P. fluorescens adherence and internalization to A549 cells. Taken together, these findings suggest that Alpha(v)Beta5 integrins and their natural ligand VN are involved in P. fluorescens adherence and invasion in human epithelial cells.

Bacterial biofilms are highly organized surface-associated communities of bacteria encased within an extracellular matrix produced by themselves, capable of growing in connection with different biological or inert surfaces such as artificial joints or catheters. Biofilms are commonly associated with many health problems, such as endocarditis, otitis media, periodontitis, prostatitis, and urinary tract infections. Several bacteria, such as Escherichia coli, Staphylococcus aureus, Streptococcus mutans, and Pseudomonas aeruginosa, or fungal pathogen as Candida albicans, can form biofilms in the body tissues, leading to different infections. The inherently defensive character of the biofilm is demonstrated by enhanced persistence of bacteria grown in the sessile mode respect to bacteria grown planktonically. This makes most biofilm- associated infections difficult to eradicate, thus contributing to disease chronicity. Since natural products provide a diverse array of chemical structures and possess a wide variety of biological properties, natural resources are worldwide exploited in the search of new pharmaceuticals. In this context bioactive secondary metabolites from natural sources, useful for the new antimicrobial and anti-biofilm drugs, are of interest. In this review, the role of small molecules from plants and marine organisms in inhibiting and/or dispersing bacterial biofilms is discussed, as well as the approaches that have been applied to the discovery of lead small molecules that mediate biofilm development. Molecules inhibiting the formation of biofilm may have therapeutic potential. Several candidates, as halogenated furanones, 2-amminoimidazole alkaloids and flavonoids have been already isolated and characterized from many plants and from marine organisms.

Statins are a class of drugs that inhibit the rate-limiting step in the cholesterol biosynthetic pathway and show an anticancer effect, probably through the inhibition of cell proliferation. To date, the exact mechanism of cancer cell growth arrest induced by statins is not known. We report that simvastatin is able to induce apoptosis in melanoma cells but not in normal cells and also able to contrast the growth of tumor in an experimental melanoma murine model. We observed a delay in the tumor development in almost the 50% of the simvastatin administered animals and a strong reduction of the tumor volume with a differences of ~150% compared to the controls. Also the survival rate was significantly higher in mice that received the drug with a survival increase of ~130% compared to the controls. The tumor growth reduction in mice was supported by the results of cell migration assay, confirming that simvastatin clearly reduced cell migration. Moreover, simvastatin induced a strong downregulation of NonO gene expression, an important growth factor involved in the splicing regulation. This result could explain the decrease of melanoma cells proliferation, suggesting a possible action mechanism. The results derived from our experiments may sustain the many reports on the anticancer inhibitory property of statins and encourage new studies on this drug for a possible use in therapy, probably in combination with conventional chemotherapy.

Two new acylated styrylpyrones, one 5-methoxy-1(3H)-isobenzofuranone glucoside and a hydroxymethyl-orcinol derivative, along with sixteen known aromatic metabolites, including lignans, quinic acid derivatives low-molecular weight phenol glucosides, have been isolated from the methanol extract of Helichrysum italicum, a medicinal plant typical of the Mediterranean vegetation. The structures of these compounds have been elucidated on the basis of extensive 2D-NMR spectroscopic analyses, including COSY, TOCSY, HSQC, CIGAR-HMBC, H2BC and HSQC-TOCSY, along with Q-TOF HRMS(2) analysis. Selected compounds were evaluated for their anti-biofilm properties against Pseudomonas aeruginosa., (Copyright © 2013. Published by Elsevier Ltd.)

Malassezia pachydermatis is a normal inhabitant of canine and feline skin that can spread to other pets. The outer layer or epidermis is made up primarily of keratinocytes, which are capable of releasing various factors and expressing receptors that are significantly involved in the immune regulation. Little is known about the mechanism by which M. pachydermatis overcomes the natural barrier of the skin. The aim of this study was to evaluate the direct in vitro interaction between human keratinocytes and a clinical strain of live M. pachydermatis isolated as a pure culture from an otitic cat. Human keratinocytes (HaCat) were infected with M. pachydermatis to analyse the modulation of the innate immune response. Gene expression was analysed by real-time PCR. We demonstrated that M. pachydermatis invaded HaCat cells and modulated the expression of TLR2 after 24h infection, while HBD-2, IL-1β TNF-α, IL-6 and IL-8 were modulated both at 24 and 48 h. Thus, our results demonstrated that M. pachydermatis is able to stimulate the innate immune response in infected human keratinocytes indicating a possible role of this yeast as a human opportunistic pathogen., (Copyright © 2012. Published by Elsevier B.V.)

Background: Helicobacter pylori infection causes chronic oxidative stress on gastric mucosa, thereby causing mucosal damage and increasing the risk of gastric adenocarcinoma. Nrf2 is an important transcription factor, regulating the antioxidant response in the cells. Nrf2 signaling is repressed by Keap1 at basal condition and induced by oxidative stress. The aim of our study was to analyze whether the H. pylori proteins interfered in the Nrf2/Keap1 pathway., Material and Methods: Gene expression in AGS cells transiently and stably transfected was analyzed by real-time PCR. Immunoprecipitation and immunofluorescence assays were performed to investigate the ability of H. pylori proteins to interfere with the Nrf2 pathway., Results: We demonstrated that the H. pylori HspB protein interferes with Nrf2/Keap1 pathway. When HspB was transiently transfected in AGS cells, a significant increase in Keap1 gene expression was induced. The same result was observed when AGS cells were HspB stably transfected. In this case, the increase in Keap1 was associated with reduced gene expression of Nrf2, and of the antioxidant enzymes superoxide dismutase, hemeoxygenase-1, and phase II detoxifying enzyme NAD(P)H:quinone oxidoreductase-1. Immunoprecipitation and immunofluorescence assays confirmed the ability of HspB protein to interfere with the Nrf2 pathway. Lastly, in HspB-transfected AGS cells, sustained activation of IL-8, COX2, MMP3, and MMP7 was demonstrated., Conclusion: The results here reported suggest that inhibited nuclear translocation of Nrf2, associated with induced inflammation and increased production of MMPs, might represent a condition enhancing the risk of gastric adenocarcinoma., (© 2012 Blackwell Publishing Ltd.)

Keratinocytes stimulated by microbial organisms secrete not only a variety of cytokines, chemokines and growth factors, but also antimicrobial peptides such as beta-defensins (HBDs) such as HBD-2 and HBD-3. AV119, a patented blend of avocado sugar, triggers the up-regulation of HBD-2 in skin epithelia upon contact with AV119, but the signalling mechanisms involved are not completely understood. The purpose of this study was to determine if AV119 was able to induce also the expression of HBD-3 in human keratinocytes. In addition, the receptor and intracellular pathways involved in the AV119 up-regulation of HBD-2 and HBD-3 were investigated. Our results demonstrated that AV119 induces a significantly increase of the expression of HBD-3. In addition, the HBD-2 and HBD-3 AV119-induced gene expression and release are TLR-2 dependent. Finally, we demonstrated that AV119 induced ERK/MAPK phosphorylation in human keratinocytes, thus providing evidence that HBD-2 and HBD-3 secretion is through the same transductional pathway. The ability of AV119 to induce also HBD-3 may amplify its therapeutic potential against a broader spectrum of bacterial and yeast strains responsible for human skin disorders.

Malignant pleural mesothelioma is a fatal malignancy linked to asbestos exposure. The main challenge for mesothelioma treatment is to go beyond the drug resistance, in particular against cisplatin (CDDP), one of the most used chemotherapeutic drug. 3-O-methylfunicone (OMF) is a metabolite produced by the fungus Penicillium pinophilum; its antiproliferative properties have been previously studied in vitro. Particularly, OMF is able to inhibit mesothelioma cell motility. To improve the effects of CDDP by-passing the resistance of mesothelioma cells to this drug, in the present study we investigated the combined treatment of OMF with CDDP respectively in an established mesothelioma cell line (NCI) and primary mesothelioma cells (Mest). As compared to the effect of single treatments, the combination of OMF and CDDP resulted in a stronger inhibition of NCI and Mest cell proliferation. OMF combination with CDDP was also able to affect the migratory ability of NCI and Mest cells by down-regulating αv and β5 expression and reducing metalloproteinase 2 (MMP-2) production. In addition, this association was effective in modulating VEGF gene expression. This finding highlights the possibility to use OMF and CDDP together to regulate angiogenesis and tumour progression in mesothelioma.

Penicillium species are a widespread source of biologically active compounds and enzymes which are exploited in biotechnologies. The ongoing discovery of new species, their biochemical and molecular characterization, and the application of the new findings in diverse industrial processes stimulate an increasing interest of patentees worldwide. An overview of the patents released in the last four years in agriculture, bioremediation, and in several industrial fields for the production of biofuels, food, cosmetics and pharmaceuticals is proposed for an exhaustive appreciation of the potential cues offered to inventors by these fungi.

The most important function of the skin is the formation of a barrier between the "inside" and the "outside" of the organism, which prevents invasion of pathogens and fends off chemical assaults as well as the unregulated loss of water and solutes. The physical barrier is mainly localized in the stratum corneum, which consists of protein-enriched cells and lipid-enriched intercellular domains. Any modifications in epidermal differentiation and lipid composition results in altered barrier function, a central event in various skin alterations and diseases. This contribution presents a brief description of the structure of the skin, paying attention to the most important components responsible for skin barrier function., (Copyright © 2012. Published by Elsevier Inc.)