Inhibition of inflammatory response in human keratinocytes by magnetic nanoparticles functionalized with PBP10 peptide derived from the PIP2-binding site of human plasma gelsolin

Applications of peptides in nanosystems for diagnosing and managing bacterial sepsis

Sepsis represents a critical medical condition stemming from an imbalanced host immune response to infections, which is linked to a significant burden of disease. Despite substantial efforts in laboratory and clinical research, sepsis remains a prominent contributor to mortality worldwide. Nanotechnology presents innovative opportunities for the advancement of sepsis diagnosis and treatment. Due to their unique properties, including diversity, ease of synthesis, biocompatibility, high specificity, and excellent pharmacological efficacy, peptides hold great potential as part of nanotechnology approaches against sepsis. Herein, we present a comprehensive and up-to-date review of the applications of peptides in nanosystems for combating sepsis, with the potential to expedite diagnosis and enhance management outcomes. Firstly, sepsis pathophysiology, antisepsis drug targets, current modalities in management and diagnosis with their limitations, and the potential of peptides to advance the diagnosis and management of sepsis have been adequately addressed. The applications have been organized into diagnostic or managing applications, with the last one being further sub-organized into nano-delivered bioactive peptides with antimicrobial or anti-inflammatory activity, peptides as targeting moieties on the surface of nanosystems against sepsis, and peptides as nanocarriers for antisepsis agents. The studies have been grouped thematically and discussed, emphasizing the constructed nanosystem, physicochemical properties, and peptide-imparted enhancement in diagnostic and therapeutic efficacy. The strengths, limitations, and research gaps in each section have been elaborated. Finally, current challenges and potential future paths to enhance the use of peptides in nanosystems for combating sepsis have been deliberately spotlighted. This review reaffirms peptides' potential as promising biomaterials within nanotechnology strategies aimed at improving sepsis diagnosis and management.

Semi-purified Antimicrobial Proteins from Oyster Hemolymph Inhibit Pneumococcal Infection

Pneumococcal infections caused by Streptococcus pneumoniae are a leading cause of morbidity and mortality globally, particularly among children. The ability of S. pneumoniae to form enduring biofilms makes treatment inherently difficult, and options are further limited by emerging antibiotic resistance. The discovery of new antibiotics, particularly those with antibiofilm activity, is therefore increasingly important. Antimicrobial proteins and peptides (AMPs) from marine invertebrates are recognised as promising pharmacological leads. This study determined the in vitro antibacterial activity of hemolymph and unique protein fractions from an Australian oyster (Saccostrea glomerata) against multi-drug-resistant S. pneumoniae. We developed a successful method for hemolymph extraction and separation into 16 fractions by preparative HPLC. The strongest activity was observed in fraction 7: at 42 µg/mL protein, this fraction was bactericidal to S. pneumoniae and inhibited biofilm formation. Proteomic analysis showed that fraction 7 contained relatively high abundance of carbonic anhydrase, cofilin, cystatin B-like, and gelsolin-like proteins, while surrounding fractions, which showed lower or no antibacterial activity, contained these proteins in lower abundance or not at all. This work supports traditional medicinal uses of oysters and contributes to further research and development of novel hemolymph/AMP-based treatments for pneumococcal infections.

Peptide-containing nanoformulations: Skin barrier penetration and activity contribution

Transdermal drug delivery presents a less invasive pathway, circumventing the need to pass through the gastrointestinal tract and liver, thereby reducing drug breakdown, initial metabolism, and gastrointestinal discomfort. Nevertheless, the unique composition and dense structure of the stratum corneum present a significant barrier to transdermal delivery. This article presents an overview of the current developments in peptides and nanotechnology to address this challenge. Initially, we sum up peptide-containing nanoformulations for transdermal drug delivery, examining them through the lenses of both inorganic and organic materials. Particular emphasis is placed on the diverse roles that peptides play within these nanoformulations, including conferring functionality upon nanocarriers and enhancing the biological efficacy of drugs. Subsequently, we summarize innovative strategies for enhancing skin penetration, categorizing them into passive and active approaches. Lastly, we discuss the therapeutic potential of peptide-containing nanoformulations in addressing a range of diseases, drawing insights from the biological activities and functions of peptides. Furthermore, the challenges hindering clinical translation are also discussed, providing valuable insights for future advancements in transdermal drug delivery.

Ceragenin CSA-13 displays high antibacterial efficiency in a mouse model of urinary tract infection

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.

Anti-Oxidant and Anti-Aging Activities of Callus Culture from Three Rice Varieties

The aims of this study were to induce calli from the seeds of three rice varieties (Hommali 105, Munpu, and Niawdum) and investigate their anti-aging potential. First, rice seeds were cultured on a Murashige and Skoog medium (MS medium) supplemented with 2 mg/L of 2,4-Dichlorophenoxyacetic acid (2,4-D), 1 mg/L of 1-Naphthalene acetic acid (NAA), and 1 mg/L of 6-Benzylaminopurine (BAP). After three weeks, the calli were extracted with ethanol. Then, their phenolic contents were determined by spectrophotometer and the amino acids were identified by ultra-performance liquid chromatography (UPLC). Their cytotoxicity, anti-oxidant (potassium ferricyanide reducing power assay (PFRAP), DPPH radical scavenging assay (DPPH), lipid peroxidation inhibition (LPO), and superoxide dismutase activity (SOD)), and anti-aging (keratinocyte proliferation, anti-collagenase, anti-inflammation, and anti-tyrosinase) activities were also investigated. Munpu callus (385%) was obtained with a higher yield than Hommali (322%) and Niawdum (297%) calli. The results revealed that the phenolic and amino acid contents were enhanced in the calli. Moreover, the calli were rich in glutamic acid, alanine, and gamma aminobutyric acid (GABA). The callus extracts showed no cytotoxic effects at a concentration of equal to or lower than 0.25 mg/mL. The highest anti-oxidant activities (PFRAP (0.81 mg AAE/mL), DPPH (68.22%), LPO (52.21%), and SOD (67.16%)) was found in Munpu callus extract. This extract also had the highest keratinocyte proliferation (43.32%), anti-collagenase (53.83%), anti-inflammation (85.40%), and anti-tyrosinase (64.77%) activities. The experimental results suggest that the amounts of bioactive compounds and anti-aging activities of rice seeds can be enhanced by the induction of callus formation.

Plasma Gelsolin Confers Chemoresistance in Ovarian Cancer by Resetting the Relative Abundance and Function of Macrophage Subtypes

Simple Summary

Ovarian cancer is one of the deadliest female cancers with very poor survival, primarily due to late diagnosis, recurrence and chemoresistance. Although the over-expression of plasma gelsolin (pGSN) protects ovarian cancer cells from chemotherapy-induced death, its immunological role in the tumor microenvironment is less explored. Here, we demonstrate that pGSN over-expression downregulates the anti-tumor functions of M1 macrophages, an effect that contributes to chemoresistance and poor patient survival. This study demonstrates the novel inhibitory role of pGSN on tumor-infiltrated M1 macrophages and also offers new insights in maximizing the effectiveness of immunotherapy for ovarian cancer patients.

Abstract

Ovarian cancer (OVCA) is the most lethal gynaecological cancer with a 5-year survival rate less than 50%. Despite new therapeutic strategies, such as immune checkpoint blockers (ICBs), tumor recurrence and drug resistance remain key obstacles in achieving long-term therapeutic success. Therefore, there is an urgent need to understand the cellular mechanisms of immune dysregulation in chemoresistant OVCA in order to harness the host’s immune system to improve survival. The over-expression of plasma gelsolin (pGSN) mRNA is associated with a poorer prognosis in OVCA patients; however, its immuno-modulatory role has not been elucidated. In this study, for the first time, we report pGSN as an inhibitor of M1 macrophage anti-tumor functions in OVCA chemoresistance. Increased epithelial pGSN expression was associated with the loss of chemoresponsiveness and poor survival. While patients with increased M1 macrophage infiltration exhibited better survival due to nitric-oxide-induced ROS accumulation in OVCA cells, cohorts with poor survival had a higher infiltration of M2 macrophages. Interestingly, increased epithelial pGSN expression was significantly associated with the reduced survival benefits of infiltrated M1 macrophages, through apoptosis via increased caspase-3 activation and reduced production of iNOS and TNFα. Additionally, epithelial pGSN expression was an independent prognostic marker in predicting progression-free survival. These findings support our hypothesis that pGSN is a modulator of inflammation and confers chemoresistance in OVCA, in part by resetting the relative abundance and function of macrophage subtypes in the ovarian tumor microenvironment. Our findings raise the possibility that pGSN may be a potential therapeutic target for immune-mediated chemoresistance in OVCA.

Targeting bacteria causing otitis media using nanosystems containing nonspherical gold nanoparticles and ceragenins

Aim: To evaluate the antibacterial and antibiofilm activity of ceragenin-conjugated nonspherical gold nanoparticles against the most common agents of otitis media. Methods: Minimal inhibitory and bactericidal concentrations and colony-counting assays, as well as colorimetric and fluorimetric methods, were used to estimate the antibacterial activity of compounds in phosphate-buffered saline and human cerumen. The nanosystems' biocompatibility and ability to decrease IL-8 release was tested using keratinocyte cells. Results: The tested compounds demonstrated strong antimicrobial activity against planktonic and biofilm cultures at nontoxic doses due to the induction of oxidative stress followed by the damage of bacterial membranes. Conclusion: This study indicates that ceragenin-conjugated nonspherical gold nanoparticles have potential as new treatment methods for eradicating biofilm-forming pathogens associated with otitis media.

Anti-Inflammatory Effect of Liverwort (Marchantia polymorpha L.) and Racomitrium Moss (Racomitrium canescens (Hedw.) Brid.) Growing in Korea

Bryophytes contain a variety of bioactive metabolites, but studies about the anti-inflammatory effect of bryophytes are meager. Therefore, the present study aimed to compare the anti-inflammatory effect of methanol extract of Marchantia polymorpha L. (liverwort) and Racomitrium canescens (Racomitrium moss) in lipopolysaccharide (LPS)-induced HaCaT cells. To evaluate the anti-inflammatory effect of liverwort and Racomitrium moss, the levels of nitric oxide (NO) production and the mRNA expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and tumor necrosis factor-α (TNF-α), and interleukin (IL)-6 and IL-1β in LPS-induced HaCaT cells were measured. The methanol extract of liverwort and Racomitrium moss significantly decreased LPS-induced NO production in HaCaT cells. When compared with Racomitrium moss extract, pre-treatment with methanol extract of liverwort markedly inhibited the expression of iNOS, COX-2, IL-6, and IL-1β at the concentration of 100 µg/mL with the exception of TNF-α. Further, liverwort extract markedly attenuated the production of TNF-α, IL-6, and IL-1β in the culture medium. In addition, ethyl acetate and butanol fractions obtained from the methanol extract of liverwort showed remarkable inhibitory activity against the production of NO in LPS-stimulated HaCaT cells. The LC-MS data revealed the presence of bisbibenzyl types of bioactive components in the methanol extract of liverwort. These data demonstrate that liverwort extract exhibits effective inhibitory activity against the production of inflammatory mediators in LPS-induced HaCaT cells and may be useful for the treatment of inflammation-mediated diseases.

New Insights into the Pivotal Role of Iron/Heme Metabolism in TLR4/NF-κB Signaling-Mediated Inflammatory Responses in Human Monocytes

Iron metabolism and heme biosynthesis are essential processes in cells during the energy cycle. Alteration in these processes could create an inflammatory condition, which results in tumorigenesis. Studies are conducted on the exact role of iron/heme metabolism in induced inflammatory conditions. This study used lipopolysaccharide (LPS)- or high-glucose-induced inflammation conditions in THP-1 cells to study how iron/heme metabolism participates in inflammatory responses. Here, we used iron and heme assays for measuring total iron and heme. We also used flow cytometry and Western blotting to analyze molecular responses. Our results demonstrated that adding LPS or high-glucose induced iron formation and heme synthesis and elevated the expression levels of proteins responsible for iron metabolism and heme synthesis. We then found that further addition of heme or 5-aminolevulinic acid (ALA) increased heme biosynthesis and promoted inflammatory responses by upregulating TLR4/NF-κB and inflammatory cytokine expressions. We also demonstrated the inhibition of heme synthesis using succinylacetone (SA). Moreover, N-MMP inhibited LPS- or high-glucose-induced inflammatory responses by inhibiting TLR4/NF-κB signaling. Hence, iron/heme metabolism checkpoints could be considered a target for treating inflammatory conditions.

Chitosan functionalized graphene oxide nanocomposites for fluorescence imaging of apoptotic processes and targeted anti-inflammation study

This work reports novel chitosan functionalized graphene oxide (GO) nanocomposites combined fluorescence imaging and therapeutic functions in one agent, which can serve as a promising alternative to alleviate related diseases caused hyperinflammation. Briefly, GO was designed to be conjugated with chitosan, fluorescein-labeled peptide, toll-like receptor 4 antibody and hydroxycamptothecin/aloe emodin. We have demonstrated that such nanocomposites could effectively achieve active targeted delivery of pro-apoptotic and anti-inflammatory drugs into inflammatory cells and cause cells apoptosis by acid-responsive drug release. Moreover, confocal fluorescence imaging confirms that the drug-induced inflammatory cells apoptosis could be visualized the light-up fluorescence of fluorescein activated by caspase-3. Meanwhile, inflammatory-related biomarkers have down-regulated after the nanocomposites' treatment in both vitro and vivo experiments consistent with the results in histological sections. In summary, the bifunctional nanocomposites that possess anti-inflammation and fluorescence imaging could serve as a promising therapeutic agent for reducing hyperinflammation caused by numerous diseases.

Natural Sulfurs Inhibit LPS-Induced Inflammatory Responses through NF-κB Signaling in CCD-986Sk Skin Fibroblasts

Lipopolysaccharide (LPS)-induced inflammatory response leads to serious damage, up to and including tumorigenesis. Natural mineral sulfur, non-toxic sulfur (NTS), and methylsulfonylmethane (MSM) have anti-inflammatory activity that may inhibit LPS-induced inflammation. We hypothesized that sulfur compounds could inhibit LPS-induced inflammatory responses in CCD-986Sk skin fibroblasts. We used Western blotting and real-time PCR to analyze molecular signaling in treated and untreated cultures. We also used flow cytometry for cell surface receptor analysis, comet assays to evaluate DNA damage, and ELISA-based cytokine detection. LPS induced TLR4 activation and NF-κB signaling via canonical and protein kinase C (PKC)-dependent pathways, while NTS and MSM downregulated that response. NTS and MSM also inhibited LPS-induced nuclear accumulation and binding of NF-κB to proinflammatory cytokines COX-2, IL-1β, and IL-6. Finally, the sulfur compounds suppressed LPS-induced ROS accumulation and DNA damage in CCD-986Sk cells. These results suggest that natural sulfur compounds could be used to treat inflammation and may be useful in the development of cosmetics.

Addressing Antimicrobial Resistance Through Nanoantibiotics

In recent years, the irrational use of antibiotics has escalated the evolution of multidrug-resistant (MDR) bacterial strains. The infectious diseases caused by these MDR bacterial strains remain a major threat to human health and have emerged as the leading cause of morbidity and mortality. The WHO and CDC have expressed serious concern regarding the continued increase in the development of multidrug resistance among bacteria. The antimicrobial resistance (AMR) poses a severe global threat of growing concern to human health and economic burden. Bacteria have developed the ability to resist antimicrobials by altering target site/enzyme, inactivation of the enzyme, decreasing cell permeability, increasing efflux due to over-expression of efflux pumps, target protection, target overproduction, and many other ways. The shortage of new antimicrobials and rapid rise in antibiotic resistance demands pressing need to develop alternate antibacterial agents.

Physics Comes to the Aid of Medicine-Clinically-Relevant Microorganisms through the Eyes of Atomic Force Microscope

Despite the hope that was raised with the implementation of antibiotics to the treatment of infections in medical practice, the initial enthusiasm has substantially faded due to increasing drug resistance in pathogenic microorganisms. Therefore, there is a need for novel analytical and diagnostic methods in order to extend our knowledge regarding the mode of action of the conventional and novel antimicrobial agents from a perspective of single microbial cells as well as their communities growing in infected sites, i.e., biofilms. In recent years, atomic force microscopy (AFM) has been mostly used to study different aspects of the pathophysiology of noninfectious conditions with attempts to characterize morphological and rheological properties of tissues, individual mammalian cells as well as their organelles and extracellular matrix, and cells’ mechanical changes upon exposure to different stimuli. At the same time, an ever-growing number of studies have demonstrated AFM as a valuable approach in studying microorganisms in regard to changes in their morphology and nanomechanical properties, e.g., stiffness in response to antimicrobial treatment or interaction with a substrate as well as the mechanisms behind their virulence. This review summarizes recent developments and the authors’ point of view on AFM-based evaluation of microorganisms’ response to applied antimicrobial treatment within a group of selected bacteria, fungi, and viruses. The AFM potential in development of modern diagnostic and therapeutic methods for combating of infections caused by drug-resistant bacterial strains is also discussed.

Serum Protein Corona Abolishes Changes in the Expression of Proinflammatory Genes Induced by Quantum Dots in Human Blood Mononuclear Cell

We studied changes in the transcription of genes encoding cytokines (TNF, IL-6, IL-10, and IL-32), cell activation markers (ICAM1, CD38, Fas, and FCGRIII), ROS production catalyst (NOX2), autophagy (Beclin 1, LC3B, and p62) and apoptosis (BAX, BCL2) regulators in peripheral blood mononuclear cells upon contact with quantum dots CdSe/ZnS-MPA and CdSe/CdSeZnS/ZnS-PTVP. Up-regulation of TNF, ICAM1, Fas, p62 mRNA and down-regulation of the FCGRIII and NOX2 mRNA in response to the presence of quantum dots were revealed. The formation of serum protein corona on the surface of quantum dots abolished this effect.

Nanoantibiotics containing membrane-active human cathelicidin LL-37 or synthetic ceragenins attached to the surface of magnetic nanoparticles as novel and innovative therapeutic tools: current status and potential future applications

Nanotechnology-based therapeutic approaches have attracted attention of scientists, in particular due to the special features of nanomaterials, such as adequate biocompatibility, ability to improve therapeutic efficiency of incorporated drugs and to limit their adverse effects. Among a variety of reported nanomaterials for biomedical applications, metal and metal oxide-based nanoparticles offer unique physicochemical properties allowing their use in combination with conventional antimicrobials and as magnetic field-controlled drug delivery nanocarriers. An ever-growing number of studies demonstrate that by combining magnetic nanoparticles with membrane-active, natural human cathelicidin-derived LL-37 peptide, and its synthetic mimics such as ceragenins, innovative nanoagents might be developed. Between others, they demonstrate high clinical potential as antimicrobial, anti-cancer, immunomodulatory and regenerative agents. Due to continuous research, knowledge on pleiotropic character of natural antibacterial peptides and their mimics is growing, and it is justifying to stay that the therapeutic potential of nanosystems containing membrane active compounds has not been exhausted yet.

Vitamin E preconditioning alleviates in vitro thermal stress in cultured human epidermal keratinocytes

AIMS

Thermal burns are the most common type of skin injuries. Clinically, the deteriorating thermal wounds have been successfully treated with skin cell sheets, suspensions or bioengineered skin substitutes. After thermal injury, oxidative microenvironment prevalent in the burnt tissue due to imbalance between production of free radicals and antioxidants defense aiding to destruction of cellular or tissue components. However, depleted antioxidant content particularly vitamin E after heat injury challenges efficient regenerative and healing capacity of transplanted cells. Thus, aim of current study was to pretreat human epidermal keratinocytes with vitamin E in order to enhance their survival rate and therapeutic ability under oxidative microenvironment induced by in vitro heat stress.

MAIN METHODS

Keratinocytes were treated with 100 μM vitamin E at 37 °C for 24 h followed by thermal stress at 51 °C for 10 min. Cell viability and cytotoxicity assays, gene expression analysis and paracrine release analysis were performed.

KEY FINDINGS

Vitamin E preconditioning resulted in significantly improved cell morphology, enhanced viability and reduced lactate dehydrogenase release. Furthermore, Vitamin E preconditioned cells exposed to thermal stress showed significant down-regulated expression of BAX and up-regulated expression of PCNA, BCL-XL, vascular endothelial growth factor (VEGF), involucrin, transglutaminase 1 (TGM1) and filaggrin (FLG) escorted by increased paracrine release of VEGF, basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF).

SIGNIFICANCE

Results of the current study suggest that clinical transplantation of vitamin E preconditioned keratinocytes alone or in combination with dermal fibroblasts in skin substitutes for the treatment of thermally injured skin.

Susceptibility of microbial cells to the modified PIP2-binding sequence of gelsolin anchored on the surface of magnetic nanoparticles

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.