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Szczepan Kaliniak,1 Krzysztof Fiedoruk,2 Jakub Spałek,1,3 Ewelina Piktel,2 Bonita Durnaś,1,3 Stanisław Góźdź,1,3 Robert Bucki,2,3 Sławomir Okła1,3 1Holy-Cross Cancer Center, Kielce, Poland; 2Department of Medical Microbiology and Nanobiomedical Engineering, Medical University of Białystok, Białystok, Poland; 3Institute of Medical Science, Collegium Medicum, Jan Kochanowski University of Kielce, Kielce, 25-317, PolandCorrespondence: Sławomir Okła, Department of Otolaryngology, Head and Neck Surgery, Holy-Cross Cancer Center, Kielce, 25-734, Poland, Tel/Fax +48 41 367 43 36, Email laryngologsco@gmail.comAbstract: Rhinosinusitis (RS) is an acute (ARS) or chronic (CRS) inflammatory disease of the nasal and paranasal sinus mucosa. CRS is a heterogeneous condition characterized by distinct inflammatory patterns (endotypes) and phenotypes associated with the presence (CRSwNP) or absence (CRSsNP) of nasal polyps. Mucosal barrier and mucociliary clearance dysfunction, inflammatory cell infiltration, mucus hypersecretion, and tissue remodeling are the hallmarks of CRS. However, the underlying factors, their priority, and the mechanisms of inflammatory responses remain unclear. Several hypotheses have been proposed that link CRS etiology and pathogenesis with host (eg, “immune barrier”) and exogenous factors (eg, bacterial/fungal pathogens, dysbiotic microbiota/biofilms, or staphylococcal superantigens). The abnormal interplay between these factors is likely central to the pathophysiology of CRS by triggering compensatory immune responses. Here, we discuss the role of the sinonasal microbiota in CRS and its biofilms in the context of mucosal zinc (Zn) deficiency, serving as a possible unifying link between five host and “bacterial” hypotheses of CRS that lead to sinus mucosa remodeling. To date, no clear correlation between sinonasal microbiota and CRS has been established. However, the predominance of Corynebacteria and Staphylococci and their interspecies relationships likely play a vital role in the formation of the CRS-associated microbiota. Zn-mediated “nutritional immunity”, exerted via calprotectin, alongside the dysregulation of Zn-dependent cellular processes, could be a crucial microbiota-shaping factor in CRS. Similar to cystic fibrosis (CF), the role of SPLUNC1-mediated regulation of mucus volume and pH in CRS has been considered. We complement the biofilms’ “mechanistic” and “mucin” hypotheses behind CRS pathogenesis with the “structural” one – associated with bacterial “corncob” structures. Finally, microbiota restoration approaches for CRS prevention and treatment are reviewed, including pre- and probiotics, as well as Nasal Microbiota Transplantation (NMT).Keywords: rhinosinusitis, chronic rhinosinusitis, nasal polyps, rhinosinusitis pathophysiology, rhinosinusitis pathophysiology, microbiota, nutritional immunity

Paulina Paprocka,1 Bonita Durnaś,1,2 Angelika Mańkowska,1 Karol Skłodowski,3 Grzegorz Król,1 Magdalena Zakrzewska,3 Michał Czarnowski,3 Patrycja Kot,1 Kamila Fortunka,1 Stanisław Góźdź,2 Paul B Savage,4 Robert Bucki1,3 1Department of Microbiology and Immunology, Institute of Medical Science, Collegium Medicum, Jan Kochanowski University in Kielce, Kielce, Poland; 2Holy Cross Oncology Center of Kielce, Kielce, Poland; 3Department of Medical Microbiology and Nanobiomedical Engineering, Medical University of Białystok, Białystok, Poland; 4Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, USACorrespondence: Robert Bucki Tel +48-85-7485493Fax +48-85 748 54 16Email buckirobert@gmail.comBackground: The increasing number of infections caused by antibiotic resistant strains of Pseudomonas aeruginosa posed a very serious challenge for clinical practice. This standing is driving scientists to develop new antibiotics against these microorganisms.Methods: In this study, we measured the MIC/MBC values and estimated the ability of tested molecules to prevent bacterial biofilm formation to explore the effectiveness of β-lactam antibiotics ceftolozane/tazobactam, ceftazidime/avibactam, meropenem/vaborbactam, and ceragenins CSA-13, CSA-44, and CSA-131 against 150 clinical isolates of Pseudomonas aeruginosa that were divided into five groups, based on their antibiotic resistance profiles to beta-lactams. Selected strains of microorganisms from each group were also subjected to prolonged incubations (20 passages) with ceragenins to probe the development of resistance towards those molecules. Cytotoxicity of tested ceragenins was evaluated using human red blood cell (RBCs) hemolysis and microscopy observations of human lung epithelial A549 cells after ceragenin treatment. Poloxamer 407 (pluronic F-127) at concentrations ranging from 0.5% to 5% was tested as a potential drug delivery substrate to reduce ceragenin toxicity.Results: Collected data proved that ceragenins at low concentrations are highly active against clinical strains of Pseudomonas aeruginosa regardless of their resistance mechanisms to conventional antibiotics. Ceragenins also show low potential for resistance development, high antibiofilm activity, and controlled toxicity when used together with poloxamer 407.Conclusion: This data strongly supports the need for further study directed to develop this group of molecules as new antibiotics to fighting infections caused by antibiotic resistant strains of Pseudomonas aeruginosa.Keywords: ceragenin, antibacterial agents, Pseudomonas aeruginosa, antibiotic resistant bacteria, new antibiotics

Katarzyna Niemirowicz-Laskowska,1 Katarzyna Głuszek,1 Ewelina Piktel,1 Karlis Pajuste,2 Bonita Durnaś,3 Grzegorz Król,3 Agnieszka Z Wilczewska,4 Paul A Janmey,5 Aiva Plotniece,2 Robert Bucki1 1Department of Microbiological and Nanobiomedical Engineering, Medical University of Bialystok, Bialystok, Poland; 2Laboratory of Membrane Active Compounds and β-Diketones, Latvian Institute of Organic Synthesis, Riga, Latvia; 3Department of Microbiology and Immunology, The Faculty of Health Sciences of the Jan Kochanowski University in Kielce, Kielce, 4Institute of Chemistry, University of Bialystok, Białystok, Poland; 5Department of Physiology, Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, PA, USA Background: 1,4-Dihydropyridine (1,4-DHP) and its derivatives are well-known calcium channel blockers with antiarrhythmic and antihypertensive activities. These compounds exhibit pleiotropic effects including antimicrobial activities that rely on their positive charge and amphipathic nature. Use of magnetic nanoparticles (MNPs) as carriers of 1,4-DHP modulates their properties and enables improved formulations with higher efficacy and less toxicity. Methods: In this study, the antimicrobial and immunomodulatory activities of novel 1,4-DHP derivatives in free form and immobilized on MNPs were determined by evaluating pathogen outgrowth and proinflammatory cytokine release in experimental settings that involve incubation of various 1,4-DHPs with clinical isolates of bacteria or fungi as well as mammalian cell culture models. Results: Conventional immobilization of 1,4-DHP on aminosilane-coated MNPs markedly enhances their antimicrobial activity compared to nonimmobilized molecules, in part because of the higher affinity of these nanosystems for bacterial cell wall components in the presence of human body fluids. Conclusion: Optimized nanosystems are characterized by improved biocompatibility and higher anti-inflammatory properties that provide new opportunities for the therapy of infectious diseases. Keywords: magnetic nanoparticles, 1,4-dihydropyridine, antibacterial, antifungal, immunomodulatory properties

Robert Bucki,1,* Bonita Durnaś,2,* Marzena Wątek,2,3 Ewelina Piktel,1 Katrina Cruz,4 Przemysław Wolak,2 Paul B Savage,5 Paul A Janmey4 1Department of Microbiological and Nanobiomedical Engineering, Medical University of Białystok, Białystok, 2Department of Microbiology and Immunology, The Faculty of Health Sciences of the Jan Kochanowski University in Kielce, 3Holy Cross Oncology Center of Kielce, Kielce, Kielce, Poland; 4Department of Physiology, Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, PA, 5Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, USA *These authors contributed equally to this work Abstract: The response of the human immune system to most bacterial infections results in accumulation of neutrophils at infection sites that release a significant quantity of DNA and F-actin. Both are negatively charged polyelectrolytes that can interact with positively charged host defense molecules such as cathelicidin-delivered LL-37 peptide or other cationic antibiotic agents. Evaluation of the ability of bacterial outgrowth (using luminescence measurements or counting colony-forming units) to form a biofilm (quantified by crystal violet staining) and analysis of the structure of DNA/F-actin network by optical microscopy in human pus samples treated with different antibiotics in combination with plasma gelsolin, DNAse 1, and/or poly-aspartic acid revealed that bactericidal activity of most tested antibacterial agents increases in the presence of DNA/F-actin depolymerizing factors. Keywords: antibiotic activity, polyelectrolyte network, depolymerizing factors, cathelicidin, ceragenins, DNase 1, cystic fibrosis

Katarzyna Niemirowicz,1 Ewelina Piktel,1 Agnieszka Z Wilczewska,2 Karolina H Markiewicz,2 Bonita Durnaś,3 Marzena Wątek,4 Irena Puszkarz,3 Marta Wróblewska,5,6 Wieslawa Niklińska,7 Paul B Savage,8 Robert Bucki1,3 1Department of Microbiological and Nanobiomedical Engineering, Medical University of Bialystok, 2Institute of Chemistry, University of Bialystok, Bialystok, 3Department of Physiology, Pathophysiology and Immunology of Infections, The Faculty of Health Sciences of the Jan Kochanowski University in Kielce, 4Holy Cross Oncology Center of Kielce, Kielce, 5Department of Dental Microbiology, Medical University of Warsaw, 6Department of Microbiology, Central Clinical Hospital in Warsaw, Warsaw, 7Department of Histology and Embryology, Medical University of Bialystok, Bialystok, Poland; 8Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, USA Abstract: Core–shell magnetic nanoparticles (MNPs) are promising candidates in the development of new treatment methods against infections, including those caused by antibiotic-resistant pathogens. In this study, the bactericidal activity of human antibacterial peptide cathelicidin LL-37, synthetic ceragenins CSA-13 and CSA-131, and classical antibiotics vancomycin and colistin, against methicillin-resistant Staphylococcus aureus Xen 30 and Pseudomonas aeruginosa Xen 5, was assessed alone and in combination with core–shell MNPs. Fractional inhibitory concentration index and fractional bactericidal concentration index were determined by microdilution methods. The potential of combined therapy using nanomaterials and selected antibiotics was confirmed using chemiluminescence measurements. Additionally, the ability of tested agents to prevent bacterial biofilm formation was evaluated using crystal violet staining. In most conditions, synergistic or additive effects were observed when combinations of core–shell MNPs with ceragenins or classical antibiotics were used. Our study revealed that a mixture of membrane-active agents such as LL-37 peptide or ceragenin CSA-13 with MNPs potentialized their antibacterial properties and might be considered as a method of delaying and overcoming bacterial drug resistance. Keywords: synergistic activity, antibiotic-resistant bacteria, LL-37 peptide, ceragenins, magnetic nanoparticles

Acne vulgaris (AV) is a chronic inflammatory condition of the pilosebaceous units characterized by multiple immunologic, metabolic, hormonal, genetic, psycho-emotional dysfunctions, and skin microbiota dysbiosis. The latter is manifested by a decreased population (phylotypes, i.e., genetically distinct bacterial subgroups that play different roles in skin health and disease) diversity of the predominant skin bacterial commensal - Cutinbacterium acnes . Like in other dysbiotic disorders, an elevated expression of endogenous antimicrobial peptides (AMPs) is a hallmark of AV. AMPs, such as human β-defensins, cathelicidin LL-37, dermcidin, or RNase-7, due to their antibacterial and immunomodulatory properties, function as the first line of defense and coordinate the host-microbiota interactions. Therefore, AMPs are potential candidates for pharmaceutical prophylaxis or treating this condition. This study outlines the current knowledge regarding the importance of AMPs in AV pathomechanism in light of recent transcriptomic studies. In particular, their role in improving the tight junctions (TJs) skin barrier by activating the fundamental cellular proteins, such as PI3K, GSK-3, aPKC, and Rac1, is discussed. We hypothesized that the increased expression of AMPs and their patterns in AV act as a compensatory mechanism to protect the skin with an impaired permeability barrier. Therefore, AMPs could be key determinants in regulating AV development and progression, linking acne-associated immune responses and metabolic factors, like insulin/IGF-1 and PI3K/Akt/mTOR/FoxO1 signaling pathways or glucotoxicity. Research and development of anti-acne AMPs are also addressed., 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 Lesiak, Paprocka, Wnorowska, Mańkowska, Król, Głuszek, Piktel, Spałek, Okła, Fiedoruk, Durnaś and Bucki.)

Background/Objectives: Bacterial vaginosis (BV), an infection caused primarily by Gardnerella vaginalis , is the most prevalent vaginal infection. Although BV is often characterized by an asymptomatic course, it can lead to considerable health complications. Currently, BV therapy choices are limited, and available treatments are complicated by concerns about antibiotic resistance. Ceragenins, which together comprise an innovative class of low molecular-weight, cholic acid-based antibacterial agents, have emerged as potential alternatives to conventional treatments. Methods: This study investigates (i) the antibacterial activity of ceragenins against G. vaginalis in in vitro experimental settings at varied pH, and (ii) the effectiveness and anti-inflammatory properties of CSA-13 in a G. vaginalis -induced bacterial vaginosis animal model. Results and Conclusions: We demonstrate that ceragenins, particularly CSA-13, maintain their antibacterial efficacy throughout pH range of 4.5-7, with the highest activity observed at neutral pH (7.0). Additionally, in an animal model, beneficial effects of ceragenins are attributed to anti-inflammatory properties of these compounds, making these compounds promising agents as potential new treatment options against G. vaginalis -associated vaginal infections.

A growing body of experimental data indicates that ceragenins (CSAs), which mimic the physicochemical properties of the host's cationic antimicrobial peptide, hold promise for the development of a new group of broad-spectrum antimicrobials. Here, using a set of in vivo experiments, we assessed the potential of ceragenins in the eradication of an important etiological agent of nosocomial infections, Acinetobacter baumannii . Assessment of the bactericidal effect of ceragenins CSA-13, CSA-44, and CSA-131 on clinical isolates of A. baumannii ( n = 65) and their effectiveness against bacterial cells embedded in the biofilm matrix after biofilm growth on abiotic surfaces showed a strong bactericidal effect of the tested molecules regardless of bacterial growth pattern. AFM assessment of bacterial cell topography, bacterial cell stiffness, and adhesion showed significant membrane breakdown and rheological changes, indicating the ability of ceragenins to target surface structures of A. baumannii cells. In the cell culture of A549 lung epithelial cells, ceragenin CSA-13 had the ability to inhibit bacterial adhesion to host cells, suggesting that it interferes with the mechanism of bacterial cell invasion. These findings highlight the potential of ceragenins as therapeutic agents in the development of antimicrobial strategies against bacterial infections caused by A. baumannii .

The growing number of infections caused by multidrug-resistant bacterial strains, limited treatment options, multi-species infections, high toxicity of the antibiotics used, and an increase in treatment costs are major challenges for modern medicine. To remedy this, scientists are looking for new antibiotics and treatment methods that will effectively eradicate bacteria while continually developing different resistance mechanisms. Ceragenins are a new group of antimicrobial agents synthesized based on molecular patterns that define the mechanism of antibacterial action of natural antibacterial peptides and steroid-polyamine conjugates such as squalamine. Since ceragenins have a broad spectrum of antimicrobial activity, with little recorded ability of bacteria to develop a resistance mechanism that can bridge their mechanism of action, there are high hopes that this group of molecules can give rise to a new family of drugs effective against bacteria resistant to currently used antibiotics. Experimental data suggests that core-shell nanosystems, in which ceragenins are presented to bacterial cells on metallic nanoparticles, may increase their antimicrobial potential and reduce their toxicity. However, studies should be conducted, among others, to assess potential long-term cytotoxicity and in vivo studies to confirm their activity and stability in animal models. Here, we summarized the current knowledge on ceragenins and ceragenin-containing nanoantibiotics as potential new tools against emerging Gram-negative rods associated with nosocomial infections.

The usage of nanotechnology in the fight against parasitic diseases is in the early stages of development, but it brings hopes that this new field will provide a solution to target the early stages of parasitosis, compensate for the lack of vaccines for most parasitic diseases, and also provide new treatment options for diseases in which parasites show increased resistance to current drugs. The huge physicochemical diversity of nanomaterials developed so far, mainly for antibacterial and anti-cancer therapies, requires additional studies to determine their antiparasitic potential. When designing metallic nanoparticles (MeNPs) and specific nanosystems, such as complexes of MeNPs, with the shell of attached drugs, several physicochemical properties need to be considered. The most important are: size, shape, surface charge, type of surfactants that control their dispersion, and shell molecules that should assure specific molecular interaction with targeted molecules of parasites' cells. Therefore, it can be expected that the development of antiparasitic drugs using strategies provided by nanotechnology and the use of nanomaterials for diagnostic purposes will soon provide new and effective methods of antiparasitic therapy and effective diagnostic tools that will improve the prevention and reduce the morbidity and mortality caused by these diseases.

Ceragenins (CSAs) are synthetic, lipid-based molecules that display activities of natural antimicrobial peptides. Previous studies demonstrated their high in vitro activity against pathogens causing urinary tract infections (UTIs), but their efficiency in vivo was not explored to date. In this study, we aimed to investigate the bactericidal efficiency of ceragenins against E. coli (Xen14 and clinical UPEC strains) isolates both in vitro and in vivo, as well to explore CSA-13 biodistribution and ability to modulate nanomechanical alterations of infected tissues using animal model of UTI. CSA-44, CSA-131 and particularly CSA-13 displayed potent bactericidal effect against tested E. coli strains, and this effect was mediated by induction of oxidative stress. Biodistribution studies indicated that CSA-13 accumulates in kidneys and liver and is eliminated with urine and bile acid. We also observed that ceragenin CSA-13 reverses infection-induced alterations in mechanical properties of mouse bladders tissue, which confirms the preventive role of CSA-13 against bacteria-induced tissue damage and potentially promote the restoration of microenvironment with biophysical features unfavorable for bacterial growth and spreading. These data justify the further work on employment of CSA-13 in the treatment of urinary tract infections., (© 2022. The Author(s).)

P seudomonas aeruginosa ( P. aeruginosa ) is one of the most frequent opportunistic microorganisms causing infections in oncological patients, especially those with neutropenia. Through its ability to adapt to difficult environmental conditions and high intrinsic resistance to antibiotics, it successfully adapts and survives in the hospital environment, causing sporadic infections and outbreaks. It produces a variety of virulence factors that damage host cells, evade host immune responses, and permit colonization and infections of hospitalized patients, who usually develop blood stream, respiratory, urinary tract and skin infections. The wide intrinsic and the increasing acquired resistance of P. aeruginosa to antibiotics make the treatment of infections caused by this microorganism a growing challenge. Although novel antibiotics expand the arsenal of antipseudomonal drugs, they do not show activity against all strains, e.g., MBL (metalo-β-lactamase) producers. Moreover, resistance to novel antibiotics has already emerged. Consequently, preventive methods such as limiting the transmission of resistant strains, active surveillance screening for MDR (multidrug-resistant) strains colonization, microbiological diagnostics, antimicrobial stewardship and antibiotic prophylaxis are of particular importance in cancer patients. Unfortunately, surveillance screening in the case of P. aeruginosa is not highly effective, and a fluoroquinolone prophylaxis in the era of increasing resistance to antibiotics is controversial.

Background: Stenotrophomonas maltophilia ( S. maltophilia ) is an emerging opportunistic Gram-negative rod causing nosocomial infections predominantly in immunocompromised patients. Due to its broad intrinsic resistance to antibiotics, including carbapenems and the ability to form a biofilm, it is difficult to eradicate., Methods: In this study, the benefit of combined administration (potential synergism) and anti-biofilm activity of ceragenins: CSA-13, CSA-44, and CSA-131 (synthetic mimics of natural antimicrobial peptides) with ceftazidime, levofloxacin, co-trimoxazole and colistin against clinical strains of S. maltophilia were determined using MIC/MBC (minimum inhibitory concentration/minimum bactericidal concentration), killing assays and CV staining., Results: Obtained data indicate that the ceragenins exhibit strong activity against the tested strains of S. maltophilia grown in planktonic culture and as stationary biofilms. Moreover, with some strains, the synergy of ceragenins with conventional antibiotics was observed Conclusion: Our data suggest that ceragenins are promising agents for future development of new methods for treatment of infections caused by S. maltophilia , along with its potential use in combination with conventional antibiotics.

Irritable bowel syndrome (IBS) is a common, chronic, functional disorder with a large impact on world population. Its pathophysiology is not completely revealed; however, it is certain that dysregulation of the bidirectional communications between the central nervous system (CNS) and the gut leads to motility disturbances, visceral hypersensitivity, and altered CNS processing characterized by differences in brain structure, connectivity and functional responsiveness. Emerging evidence suggests that gut microbiota exerts a marked influence on the host during health and disease. Gut microbiome disturbances can be also important for development of IBS symptoms and its modulation efficiently contributes to the therapy. In this work, we review the current knowledge about the IBS therapy, the role of gut microbiota in pathogenesis of IBS, and we discuss that its targeting may have significant impact on the effectiveness of IBS therapy.

Background: Infections caused by Candida spp. have become one of the major causes of morbidity and mortality in immunocompromised patients. Therefore, new effective fungicides are urgently needed, especially due to an escalating resistance crisis., Methods: A set of nanosystems with rod- (AuR), peanut- (AuP), and star-shaped (AuS) metal cores were synthesized. These gold nanoparticles were conjugated with ceragenins CSA-13, CSA-44, and CSA-131, and their activity was evaluated against Candida strains ( n = 21) through the assessment of MICs (minimum inhibitory concentrations)/MFCs (minimum fungicidal concentrations). Moreover, in order to determine the potential for resistance development, serial passages of Candida cells with tested nanosystems were performed. The principal mechanism of action of Au NPs was evaluated via ROS (reactive oxygen species) generation assessment, plasma membrane permeabilization, and release of the protein content. Finally, to evaluate the potential toxicity of Au NPs, the measurement of hemoglobin release from red blood cells (RBCs) was carried out., Results: All of the tested nanosystems exerted a potent candidacidal activity, regardless of the species or susceptibility to other antifungal agents. Significantly, no resistance development after 25 passages of Candida cells with AuR@CSA-13, AuR@CSA-44, and AuR@CSA-131 nanosystems was observed. Moreover, the fungicidal mechanism of action of the investigated nanosystems involved the generation of ROS, damage of the fungal cell membrane, and leakage of intracellular contents. Notably, no significant RBCs hemolysis at candidacidal doses of tested nanosystems was detected., Conclusions: The results provide rationale for the development of gold nanoparticles of rod-, peanut-, and star-shaped conjugated with CSA-13, CSA-44, and CSA-131 as effective candidacidal agents.

This study aimed to investigate the potential application of ceragenins (CSAs) as new candidacidal agents to prevent biofilm formation on voice prostheses (VPs). The deterioration of the silicone material of VPs is caused by biofilm growth on the device which leads to frequent replacement procedures and sometimes serious complications. A significant proportion of these failures is caused by Candida species. We found that CSAs have significant candidacidal activities in vitro (MIC; MFC; MBIC), and they effectively eradicate species of yeast responsible for VP failure. Additionally, in our in vitro experimental setting, when different Candida species were subjected to CSA-13 and CSA-131 during 25 passages, no tested Candida strain showed the significant development of resistance. Using liquid chromatography-mass spectrometry (LC-MS), we found that VP immersion in an ethanol solution containing CSA-131 results in silicon impregnation with CSA-131 molecules, and in vitro testing revealed that fungal biofilm formation on such VP surfaces was inhibited by embedded ceragenins. Future in vivo studies will validate the use of ceragenin-coated VP for improvement in the life quality and safety of patients after a total laryngectomy.

Aim: To investigate the fungicidal activity of rod-shaped gold nanoparticles (AuR NPs) against Candida strains isolated from hematooncological patients and representative strains of filamentous fungi. Methods: Colony-counting assays, colorimetric and fluorometric methods and atomic force microscopy were employed. Results: AuR NPs were characterized by their potent fungicidal activity against all tested isolates, regardless of the species or drug susceptibility, at concentrations that are nontoxic to the host cells. The membrane-permeabilizing properties of AuR NPs and induction of reactive oxygen species were recognized as crucial for fungicidal activity. Conclusions: The results provide a rationale for the development of nonspherical Au NPs as effective antifungals or drug-delivery carriers to improve therapy for fungal infections.

Voice prosthesis implantation with the creation of a tracheoesophageal fistula is the gold standard procedure for voice rehabilitation in patients after a total laryngectomy. All patients implanted with a voice prosthesis (VP) have biofilms of fungi and bacteria grow on their surface. Biofilm colonization is one of the main reasons for VP degradation that can lead to VP dysfunction, which increases the high risk of pneumonia. In a 20-month evaluation period, 129 cases of prostheses after replacement procedures were investigated. Microbiological examination of the biofilms revealed that there were four of the most common fungi species ( Candida spp.) and a large variety of bacterial species present. We studied the relationship between the time of proper function of Provox VP, the microorganism composition of the biofilm present on it, and the degradation level of the silicone material. Evaluation of the surface of the removed VP using an atomic force microscope (AFM) has demonstrated that biofilm growth might drastically change the silicone's mechanical properties. Changes in silicone stiffness and thermal properties might contribute to the failure of VP function. Our data can serve in future studies for the development of methods to prevent or inhibit biofilm formation on the VP surface that would translate to an increase in their durability and safety.

Plasma gelsolin (pGSN) is a highly conserved abundant circulating protein, characterized by diverse immunomodulatory activities including macrophage activation and the ability to neutralize pro-inflammatory molecules produced by the host and pathogen. Using a murine model of Gram-negative sepsis initiated by the peritoneal instillation of Pseudomonas aeruginosa Xen 5, we observed a decrease in the tissue uptake of IRDye ® 800CW 2-deoxyglucose, an indicator of inflammation, and a decrease in bacterial growth from ascitic fluid in mice treated with intravenous recombinant human plasma gelsolin (pGSN) compared to the control vehicle. Pretreatment of the murine macrophage line RAW264.7 with pGSN, followed by addition of Pseudomonas aeruginosa Xen 5, resulted in a dose-dependent increase in the proportion of macrophages with internalized bacteria. This increased uptake was less pronounced when cells were pretreated with pGSN and then centrifuged to remove unbound pGSN before addition of bacteria to macrophages. These observations suggest that recombinant plasma gelsolin can modulate the inflammatory response while at the same time augmenting host antibacterial activity.

Introduction: Over 300 species of parasites can possibly be passed on humans. Most of the parasitic infections are defined based on their pathogenicity; however, some positive effects of a parasite existence within the human body have recently been suggested. Beneficial outcomes of parasite infections might result from the production and release of metabolites, modification of host immune response or products uptake of the host., Objective: The aim of the study was a comprehensive analysis of a wide range of effects of parasites on the human body, including an overview of the toxic and positive effects., State of Knowledge: In the light of the latest research presenting the unconventional use of parasites in medicine, the widely understood of their impact on the human body can also be considered in a positive context. Clinical cases from diseases caused by the toxic effects of parasites, as described in recent years, indicate that the problem of parasitic infections still persists. Despite a great deal of knowledge about the toxic effects of parasites on the human organism and, above all, despite the improvement in sanitary conditions, there is a resurgence of parasitic infections, as evidenced, e.g. by the examples presented in this review., Conclusions: The examples of positive effects of parasites presented so far give hope for the future in terms of fighting many diseases for which pharmacological treatment has not yet brought a positive effect. A better understanding of those processes might lead to the development of new methods of unconventional medical treatment.

Acid sphingomyelinase (aSMase) is involved in the generation of metabolites that function as part of the sphingolipid signaling pathway. It catalyzes the breakdown of sphingomyelin into ceramide, a bioactive lipid that, among other roles, is involved in regulation of apoptosis. Dry drop blood test (DBS) and colorimetric 2-step enzymatic assay were used to assess the activity of human blood aSMase, beta-galactosidase, and beta-glucosidase, these enzymes are lysosomal hydrolases that catalyze the degradation of related sphingolipids, of sphingolipid signaling molecules. Blood was collected from a group of healthy volunteers and patients that were diagnosed with multiple myeloma (MM) in various stages of the disease. Additionally, activity of those enzymes in patients diagnosed with other hematological cancers was also assessed. We found that aSMase activity in the blood of patients with MM (at the time of diagnosis) was 305.43 pmol/spot*20 h, and this value was significantly lower ( p < 0.030) compared to the healthy group 441.88 pmol/spot*20 h. Our collected data suggest a possible role of aSMase in pathogenesis of MM development.

Background: Magnetic nanoparticles (MNPs) are characterized by unique physicochemical and biological properties that allow their employment as highly biocompatible drug carriers. Gelsolin (GSN) is a multifunctional actin-binding protein involved in cytoskeleton remodeling and free circulating actin sequestering. It was reported that a gelsolin derived phosphoinositide binding domain GSN 160-169, (PBP10 peptide) coupled with rhodamine B, exerts strong bactericidal activity., Results: In this study, we synthesized a new antibacterial and antifungal nanosystem composed of MNPs and a PBP10 peptide attached to the surface. The physicochemical properties of these nanosystems were analyzed by spectroscopy, calorimetry, electron microscopy, and X-ray studies. Using luminescence based techniques and a standard killing assay against representative strains of Gram-positive (Staphylococcus aureus MRSA Xen 30) and Gram-negative (Pseudomonas aeruginosa Xen 5) bacteria and against fungal cells (Candida spp.) we demonstrated that magnetic nanoparticles significantly enhance the effect of PBP10 peptides through a membrane-based mode of action, involving attachment and interaction with cell wall components, disruption of microbial membrane and increased uptake of peptide. Our results also indicate that treatment of both planktonic and biofilm forms of pathogens by PBP10-based nanosystems is more effective than therapy with either of these agents alone., Conclusions: The results show that magnetic nanoparticles enhance the antimicrobial activity of the phosphoinositide-binding domain of gelsolin, modulate its mode of action and strengthen the idea of its employment for developing the new treatment methods of infections.

Background: Urinary tract infections (UTIs) are one of the most common bacterial infections. High recurrence rates and the increasing antibiotic resistance among uropathogens constitute a large social and economic problem in current public health. We assumed that combination of treatment that includes the administration ceragenins (CSAs), will reinforce the effect of antimicrobial LL-37 peptide continuously produced by urinary tract epithelial cells. Such treatment might be an innovative approach to enhance innate antibacterial activity against multidrug-resistant E. coli., Methods: Antibacterial activity measured using killing assays. Biofilm formation was assessed using crystal violet staining. Viability of bacteria and bladder epithelial cells subjected to incubation with tested agents was determined using MTT assays. We investigated the effects of chosen molecules, both alone and in combinations against four clinical strains of E. coli, obtained from patients diagnosed with recurrent UTI., Results: We observed that the LL-37 peptide, whose concentration increases at sites of urinary infection, exerts increased bactericidal effect against E. coli when combined with ceragenins CSA-13 and CSA-131., Conclusion: We suggest that the employment of combination of natural peptide LL-37 with synthetic analogs might be a potential solution to treat urinary tract infections caused by drug-resistant bacteria.

BACKGROUND Gelsolin (GSN) is an actin-binding and PIP₂/Ca²⁺-regulated protein found in the cytoplasm and blood plasma. Hypogelsolinemia occurs in a wide range of traumatic injuries and inflammatory reactions. We hypothesize that blood GSN levels will be altered in patients diagnosed with acute myeloid leukemia (AML) that develop sepsis, and assessment of GSN concentration will be a useful marker to determine their clinical outcome. To achieve this task, we evaluated the plasma gelsolin concentration in blood samples collected from patients diagnosed with acute myeloid leukemia (AML) at initial stages of sepsis. MATERIAL AND METHODS To assess if AML patients might be at risk of sepsis, a SOFA score was determined. Plasma gelsolin concentration was evaluated using an immunoblotting technique. RESULTS We found that GSN concentration in the blood of the AML group with developing sepsis was significantly lower (32±41 µg/ml; p<0.05) compared to the AML group (65±35 µg/ml) and control group (176±37 µg/ml; p<0.001). Additionally, low gelsolin concentration in the blood of AML patients developing sepsis was associated with a high SOFA score. A decrease of GSN concentration in the blood of AML subjects with developing sepsis suggests that GSN level in blood reflects not only chronic inflammation stage associated with leukemia, but that GSN depletion also manifests the inflammation associated with sepsis development. CONCLUSIONS The results presented here suggest the possible utility of GSN evaluation for diagnostic purposes. Overall, these data support the that reversing plasma GSN deficiency might be a possible new strategy in sepsis treatment.

There is a rising number of evidence indicating the increased risk of cancer development in association with congenital metabolic errors. Although these diseases represent disorders of individual genes, they lead to the disruption of metabolic pathways resulting in metabolite accumulation or their deficiency. Gaucher disease (GD) is an autosomal recessive sphingolipidosis. It is a rare lysosomal storage disease. A strong correlation between GD and different types of cancers, such as multiple myeloma, leukemia, and hepatocellular carcinoma, has been reported. Common features for all types of GD include spleen and liver enlargement, cytopenia, and a variety of bone defects. Overall, the molecular bases leading to the association of GD and cancers are not clearly understood. Here, we describe the role of ceramides in GD, discuss the potential implications of immune cells activation and show how the disturbances in their metabolism might promote blood cancer development.

Gelsolin, an actin-depolymerizing protein expressed both in extracellular fluids and in the cytoplasm of a majority of human cells, has been recently implicated in a variety of both physiological and pathological processes. Its extracellular isoform, called plasma gelsolin (pGSN), is present in blood, cerebrospinal fluid, milk, urine, and other extracellular fluids. This isoform has been recognized as a potential biomarker of inflammatory-associated medical conditions, allowing for the prediction of illness severity, recovery, efficacy of treatment, and clinical outcome. A compelling number of animal studies also demonstrate a broad spectrum of beneficial effects mediated by gelsolin, suggesting therapeutic utility for extracellular recombinant gelsolin. In the review, we summarize the current data related to the potential of pGSN as an inflammatory predictor and therapeutic target, discuss gelsolin-mediated mechanisms of action, and highlight recent progress in the clinical use of pGSN.

Background: Impaired apoptotic pathways in leukemic cells enable them to grow in an uncontrolled way. Moreover, aberrations in the apoptotic pathways are the main factor of leukemic cells drug resistance., Methods: To assess the presence of potential abnormalities that might promote dysfunction of leukemic cells growth, HPLC system was used to determine sphingosine (SFO), sphinganine (SFA), sphingosine-1-phosphate (S1P) and ceramide (CER) concentration in the blood collected from patients diagnose with acute myeloblastic leukemia (AML; n = 49) and compare to values of control (healthily) group (n = 51). Additionally, in AML group concentration of SFO, SFA, S1P and CER was determined in bone marrow plasma and compared to respective values in blood plasma. The concentration of S1P and CER binding protein - plasma gelsolin (GSN) was also assessed in collected samples using immunoblotting assay., Results: We observed that in AML patients the average SFO, SFA and CER concentration in blood plasma was significantly higher (p < 0.001) compare to control group, when blood plasma S1P concentration was significantly lower (p < 0.001). At the same time the CER/S1P ratio in AML patient (44.5 ± 19.4) was about 54% higher compare to control group (20.9 ± 13.1). Interestingly the average concentration of S1P in blood plasma (196 ± 13 pmol/ml) was higher compare to its concentration in plasma collected from bone marrow (154 ± 21 pmol/ml)., Conclusions: We hypothesize that changes in profile of sphingolipids concentration and some of their binding protein partners such as GSN in extracellular environment of blood and bone marrow cells in leukemic patients can be targeted to develop new AML treatment method(s).

The number and diversity of chemical structures currently available as antibacterial drugs is much higher compared with the number of active substances in relation to pathogenic fungi. In this review we focus on nanotechnology approaches, which offer promising strategies to create nanoagents that possess broad-spectrum antifungal activity and might overcome mechanisms of antibiotic resistance. Special attention was given to magnetic nanoparticles and their ability to restrict fungal growth directly, which depends on surface chemistry and pathogen strains. We speculate that future developments of new antifungal methods will take advantage of the current knowledge of using of magnetic nanomaterials as anticancer agents based on their ability to induce hyperthermia and enhance photosensitizing processes.

Background: Cationic antibacterial peptides (CAPs) and synthetic molecules mimicking the amphiphilic structure of CAPs, such as ceragenins, are promising compounds for the development of new antimicrobials., Results: We tested the in vitro activity of ceragenins CSA-13 and CSA-131 against several anaerobic bacteria including Bacteroides spp. and Clostridium difficile. We compared results to the activity of cathelicidin LL-37, metronidazole and nanosystems developed by attachment of CSA-13 and CSA-131 to magnetic nanoparticles (MNPs). The antibacterial effect was tested using killing assay and modified CLSI broth microdilution assay. Ceragenins CSA-13 and CSA-131 displayed stronger bactericidal activity than LL-37 or metronidazole against all of the tested bacterial strains. Additionally CSA-131 revealed an enhanced ability to prevent the formation of Bacteroides fragilis and Propionibacterium acnes biofilms., Conclusions: These data confirmed that ceragenins display antimicrobial activity against a broad range of microorganisms including anaerobic bacteria and deserve further investigations as compounds serving to develop new treatment against anaerobic and mixed infections.

Fungal infections caused by Candida spp. represent an emerging problem during treatment of immunocompromised patients and those hospitalized with serious principal diseases. The ever-growing number of fungal strains exhibiting drug resistance necessitates the development of novel antimicrobial therapies including those based on membrane-permeabilizing agents and nanomaterials as drug carriers. In this study, the fungicidal activities of LL-37 peptide, ceragenin CSA-13 and its magnetic derivatives (MNP@LL-37, MNP@CSA-13) against laboratory and clinical strains of C. albicans, C. glabrata and C. tropicalis were evaluated. These experiments confirm the high anti-fungal activity of these well-characterized agents mediated by their interaction with the fungal membrane and demonstrate elevated activity following immobilization of LL-37 and CSA-13 on the surface of magnetic nanoparticles (MNPs). Furthermore, MNP-based nanosystems are resistant to inhibitory factors present in body fluids and effectively inhibit formation of fungal biofilm. Simultaneously, synthesized nanostructures maintain immunomodulatory properties, described previously for free LL-37 peptide and CSA-13 substrate and they do not interfere with the proliferation and viability of osteoblasts, confirming their high biocompatibility.

Beyond their role as structural molecules, sphingolipids are involved in many important cellular processes including cell proliferation, apoptosis, inflammation, and migration. Altered sphingolipid metabolism is observed in many pathological conditions including gastrointestinal diseases. Inflammatory bowel disease (IBD) represents a state of complex, unpredictable, and destructive inflammation of unknown origin within the gastrointestinal tract. The mechanisms explaining the pathophysiology of IBD involve signal transduction pathways regulating gastro-intestinal system's immunity. Progressive intestinal tissue destruction observed in chronic inflammation may be associated with an increased risk of colon cancer. Sphingosine-1-phosphate (S1P), a sphingolipid metabolite, functions as a cofactor in inflammatory signaling and becomes a target in the treatment of IBD, which might prevent its conversion to cancer. This paper summarizes new findings indicating the impact of (S1P) on IBD development and IBD-associated carcinogenesis.

This study was designed to assess the antifungal/anti-biofilm and hemolytic properties of two polyene antibiotics, amphotericin B (AMF) and nystatin (NYS), attached to the surface of magnetic nanoparticles (MNP) against clinical isolates of Candida species and human red blood cells, respectively. The developed nanosystems, MNP@AMF and MNP@NYS, displayed stronger fungicidal activity than unbound AMF or NYS. Synergistic activity was observed with a combination of polyenes and MNPs against all tested Candida strains. Nanosystems were more potent than unbound agents when tested against Candida strains in the presence of pus, and as agents able to prevent Candida biofilm formation. The observed inactivation of catalase Cat1 in Candida cells upon treatment with the nanosystems suggests that disruption of the oxidation-reduction balance is a mechanism leading to inhibition of Candida growth. The significant decrease of polyenes lytic activity against host cells after their attachment to MNPs surface indicates improvement in their biocompatibility., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Fungal infections, especially those caused by antibiotic resistant pathogens, have become a serious public health problem due to the growing number of immunocompromised patients, including those subjected to anticancer treatment or suffering from HIV infection. In this study we assessed fungicidal activity of the ceragenins CSA-13, CSA-131 and CSA-192 against four fluconazole-resistant Candida strains. We found that ceragenins activity against planktonic Candida cells was higher than activity of human LL-37 peptide and synthetic cationic peptide omiganan. Compared to LL-37 peptide, ceragenins in the presence of DNase I demonstrated an increased ability to kill DNA-induced Candida biofilm. Microscopy studies show that treatment with LL-37 or ceragenins causes Candida cells to undergo extensive surface changes indicating surface membrane damage. This conclusion was substantiated by observation of rapid incorporation of FITC-labeled CSA-13, CSA-131 or LL-37 peptide into the more lipophilic environment of the Candida membrane. In addition to activity against Candida spp., ceragenins CSA-131 and CSA-192 display strong fungicidal activity against sixteen clinical isolates including Cryptococcus neoformans and Aspergillus fumigatus. These results indicate the potential of ceragenins for future development as new fungicidal agents.

The aim of the presented study was the analysis of microbiological data obtained from patients hospitalized in The Holly Cross Cancer Center in Kielce in 2001. The frequency of important nosocomial pathogens in selected specimens and their susceptibility to antibiotics were determined. The strains were identified by using commercial tests (bioMerieux) and their antibiotic susceptibility patterns were performed by disc diffusion technique. The most prevalent bacteria were Gram-negative rods of Enterobacteriaceae family (43%), mainly Escherichia coli. Only 2.7% strains of isolated Escherichia coli isolated from clinical specimens collected from hospitalized patients were beta-lactamase--positive (ESBL+). The second important group of microorganisms were Staphylococci, followed by Enterococcus spp., Pseudomonas aeruginosa and Candida spp. About twenty eight percent of Staphylococcus aureus isolates were resistant to methicillin.