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Ants (Hymenoptera: Formicidae) play an important role in the pharmacological and food industry due to their therapeutic and nutritional properties. Being the most abundant eusocial insects in the world, ants also serve as a repository of bioactive compounds, which are utilized for their ecological interactions and defense. Ants have been used for the treatment of various diseases including asthma, cancer, arthritis, and other microbial infections in both modern and ethnic medicine. This is attributed to various compounds, such as antimicrobial peptides, biogenic amines, alkaloids, and flavonoids obtained from ant venom as well as whole‐body extracts. However, most of these compounds have not been characterized till date. Ant endosymbionts are also known to contribute to some of these properties and to play a crucial role in digestion, protection from enemies, nutritional upgrading, nitrogen recycling, and reproductive manipulation of their host. Hence, they have been used in pharmaceutical, food, and cosmetic industries due to their ability to produce various bioactive compounds. In contrast, ectosymbionts specifically help in pathogen defense. However, the potential of ant symbionts in the welfare and production of therapeutic compounds is not extensively studied. This review mainly focuses on the role of ants and their symbiotic microbes as a potential source of bioactive compounds in therapeutic interventions for exploring future possibilities in drug development research. [ABSTRACT FROM AUTHOR]

Bark protects the tree against environmental insults. Here, we analyzed whether this defensive strategy could be utilized to broadly enhance protection against colitis. As a proof of concept, we show that exosome‐like nanoparticles (MBELNs) derived from edible mulberry bark confer protection against colitis in a mouse model by promoting heat shock protein family A (Hsp70) member 8 (HSPA8)‐mediated activation of the AhR signaling pathway. Activation of this pathway in intestinal epithelial cells leads to the induction of COP9 Constitutive Photomorphogenic Homolog Subunit 8 (COPS8). Utilizing a gut epithelium‐specific knockout of COPS8, we demonstrate that COPS8 acts downstream of the AhR pathway and is required for the protective effect of MBELNs by inducing an array of anti‐microbial peptides. Our results indicate that MBELNs represent an undescribed mode of inter‐kingdom communication in the mammalian intestine through an AhR‐COPS8‐mediated anti‐inflammatory pathway. These data suggest that inflammatory pathways in a microbiota‐enriched intestinal environment are regulated by COPS8 and that edible plant‐derived ELNs may hold the potential as new agents for the prevention and treatment of gut‐related inflammatory disease. Synopsis: Mulberry bark derived exosome‐like nanoparticles (MBELNs) prevent gut inflammation via plant heat shock protein HSPA8‐mediated activation of AhR/COPS8 pathways. Treatment with MBELNs promotes the restoration of gut microbiome homeostasis, ameliorating intestinal inflammatory pathologies. Mulberry bark derived exosome‐like nanoparticles (MBELNs) prevent mouse colitis via the AhR/COPS8 pathway.Binding of MBELN‐derived heat shock protein HSPA8 to AhR leads to the activation of AhR signaling.Activation of AhR leads to the induction of an array of anti‐microbial peptides (AMPs) via COP9/COPS8.AhR/COPS8‐dependent induction of AMPs inhibits intestinal inflammation and alters fecal gut microbiota composition. [ABSTRACT FROM AUTHOR]

Objectives: Anti‐microbial peptides (AMPs) have been comprehensively investigated as a novel alternative to traditional antibiotics against microorganisms. Meanwhile, Tetrahedral DNA nanostructures (TDNs) have gained attention in the field of biomedicine for their premium biological effects and transportation efficiency as delivery vehicles. Hence, in this study, TDN/Histatin 5 (His‐5) was synthesized and the transport efficiency and anti‐fungal effect were measured to evaluate the promotion of His‐5 modified by TDNs. Materials and Methods: Tetrahedral DNA nanostructures/His‐5 complex was prepared via electrostatic attraction and characterized by transmission electron microscopy (TEM), polyacrylamide gel electrophoresis (PAGE), dynamic light scattering (DLS) and electrophoretic light scattering (ELS). The anti‐fungal effect of the TDN/His‐5 complex was evaluated by determining the growth curve and colony‐forming units of C. albicans. The morphological transformation of C. albicans was observed by light microscope and scanning electron microscope (SEM). Immunofluorescence was performed, and potassium efflux was detected to mechanistically demonstrate the efficacy of TDN/His‐5. Results: The results showed that Histatin 5 modified by TDNs had preferable stability in serum and was effectively transported into C. albicans, leading to the increased formation of intracellular reactive oxygen species, higher potassium efflux and enhanced anti‐fungal effect against C. albicans. Conclusions: Our study showed that TDN/His‐5 was synthesized successfully. And by the modification of TDNs, His‐5 showed increased transport efficiency and improved anti‐fungal effect. [ABSTRACT FROM AUTHOR]

Abstract: We have monitored the effects of KLKL5KLK (KLK), a derivative of a natural cationic antimicrobial peptide (CAP) on isolated membrane vesicles, and investigated the partition of the peptide within these structures. KLK readily interacted with fluorescent dyes entrapped in the vesicles without apparent pore formation. Fractionation of vesicles revealed KLK predominantly in the membrane. Peptide-treated vesicles appeared with generally disorganized bilayers. While KLK showed no effect on osmotic resistance of human erythrocytes, dramatic decrease in core and surface membrane fluidity was observed in peptide-treated erythrocyte ghosts as measured by fluorescence anisotropy. Finally, CD spectroscopy revealed lipid-induced random coil to β-sheet and β-sheet to α-helix conformational transitions of KLK. Together with the oligonucleotide oligo-d(IC)13 [ODN1a], KLK functions as a novel adjuvant, termed IC31™. Among other immunological effects, KLK appears to facilitate the uptake and delivery of ODN1a into cellular compartments, but the nature of KLK''s interaction with the cell surface and other membrane-bordered compartments remains unknown. Our results suggest a profound membrane interacting property of KLK that might contribute to the immunostimulatory activities of IC31™. [Copyright &y& Elsevier]

Salmonella enterica is a facultative intracellular pathogen that replicates within macrophages. The interaction of this pathogen with mammalian cells is a complex process involving hundreds of bacterial products that are sensed by and alter mammalian hosts. Numerous bacterial genes and their protein products have been identified that are required for Salmonella to resist killing by host innate immunity and to modify host processes. Many of these genes are regulated by a specific bacterial sensor, the PhoQ protein, which responds to the acidified phagosome environment. PhoQ is a sensor histidine kinase, which when activated in vivo within acidified macrophage phagosomes, regulates cell surface modifications that promote resistance to antimicrobial peptides and oxidative stress, alter the phagosome to promote intracellular survival, and reduce innate immune recognition. In this review, we discuss mechanisms by which Salmonella interacts with macrophages and focus in detail on recent reports describing the role of antimicrobial peptides and pH in PhoQ activation. [ABSTRACT FROM AUTHOR]