Katarzyna Bandurska

Unique features of human cathelicidin LL-37

Cathelicidins are antimicrobial peptides produced by humans and animals in response to various pathogenic microbes. This review intends to provide a brief overview of the expression, structure, properties and function of human cathelicidin LL‐37 which may be a therapeutic agent against a variety of bacterial and viral diseases, cancers, and hard‐to‐heal wounds. Cathelicidins act as a primary defense against bacteria and other pathogens in the case of inflammation. They are able to kill bacteria and fungi, inhibit and destroy bacterial biofilms, and possess antiviral and antiparasitics properties. They can also play a role in angiogenesis, wound healing, and the regulation of apoptosis. The host defense peptide LL‐37 has emerged as a novel modulator of tumor growth and metastasis in carcinogenesis of various types of cancers. LL‐37 is an antimicrobial peptide able of inducing various effects. It acts as an anti‐ and pro‐ inflammatory factor. Cathelicidins are able to directly and selectively destroy membranes of various microbes and cancer cells, but they do not attack normal cells. The role of cathelicidins in cancer is double‐sided. They play an important role in killing cancer cells and may provide a new possibility for the development of cancer therapeutics. However, they also can participate in carcinogenesis. Due to its activity spectrum LL‐37 could be applied in pharmacotherapy. Cathelicidin peptides could serve as a template for the development of modern anti‐microbial and anti‐viral drugs. LL‐37 is an excellent candidate to develop into therapeutics for infected wounds.

[Interferons: between structure and function].

Interferons are a family of proteins that are released by a variety of cells in response to infections caused by viruses. Currently, we distinguish three types of interferons. They are classified based on the nucleotide sequence, interaction with specific receptors, chromosomal location, structure and physicochemical properties. The following interferons are classified as type I: α, β, ω, κ, ε, ζ, τ, δ, ν. They are recognized and bound by a receptor formed by two peptides, IFN-αR1 and IFN-αR2. Representative of type II interferons is interferon-γ. It binds to a receptor composed of chains IFNGR-1 and IFNGR-2. The recently classified type III interferons comprise IFN-λ1, IFN-λ2, and IFN-λ3. They act on receptors formed by λR1 IFN-and IL-10R2 subunits. A high level of antiviral protection is achieved by IFN-α, IFN-β and IFN-λ. Antiviral activity of interferons is based on the induction and regulation of innate and acquired immune mechanisms. By binding to transmembrane receptors, IFN interacts with target cells mainly by activating the JAK/STAT, but also other signaling pathways. This leads to induction and activation of many antiviral agents, such as protein kinase RNA-activated (PKR), ribonuclease 2-5A pathway, and Mx proteins, as well as numerous apoptotic pathways. As a result of the protective effect of interferons, the virus binding to cells and viral particles penetration into cells is stopped, and the release of the nucleocapsid from an envelope is suppressed. Disruption of transcription and translation processes of the structural proteins prevents the formation of virions or budding of viruses, and as a result degradation of the viral mRNA; the started processes inhibit the chain synthesis of viral proteins and therefore further stimulate the immune system cells.

Bacterial Microbiota and Fatty Acids in the Faeces of Overweight and Obese Children

Abstract The growing number of children with overweight and obesity constitutes a major health problem of the modern world and it has been suggested that intestinal microbiota may influence energy intake from food. The objectives of this study were to determine quantity and proportions of dominant genera of Bacteroides, Prevotella (phylum Bacteroidetes); Clostridium, Lactobacillus (phylum Firmicutes) and Bifidobacterium (phylum Actinobacteria) in the intestines and to determine the content of short-chain fatty acids (SCFAs) and branched-chain fatty acids (BCFAs) in the stool of 20 obese children and 20 children with normal body weight. Strains classified as Firmicutes (Clostridium and Lactobacillus) predominated in stool microbiota of obese children, while those of Bacteroidetes (Prevotella and Bacteroides) were in minority (p < 0.001). Concentration of SCFAs in the stool of obese children was lower in comparison to the stool of normal weight children (p = 0.04). However, these differences were significant only in obese children, not in overweight children in comparison with the lean ones. Therefore, in our study obesity was associated with intestinal dysbiosis and a predominance of phylum Firmicutes. Secondly, stool of obese children contained lower amounts of SCFAs.

Adaptation of selected ectomycorrhizal fungi to increased concentration of cadmium and lead

Abstract Plants together with water and minerals actively take from the soil heavy metals such as cadmium and lead. The negative role of ions of these metals on plant growth and development depends not only on their concentration in the soil, but also on a number of factors that may affect the transport of minerals from the soil to the roots. The harmful effects of xenobiotics getting from the soil to the plants are limited by the organic compounds contained in the soil, soil structure and pH. Particularly noteworthy are biotic factors, such as bacteria and fungi which greatly limit the translocation of heavy metals. Stream of new scientific reports show that the symbiotic combination of fungi with plant roots so called mycorrhizae is a factor that may be important in reducing the impact of soil contamination by heavy metals. Mycorrhiza by filtering solutions of water and mineral salts stop a considerable amount of heavy metals in the internal mycelium or on its surface. It was proved that plants with properly formed mycorrhiza grow better in hard to renew lands, such as salty, sterile soils contaminated with industrial waste. Questions to which answer was sought in this study are: 1) whether mycorrhizal fungi for many years growing in the contaminated areas have managed to adapt to these adverse conditions and 2) do the same species derived from clean areas are less resistant to contamination by heavy metals? Stated problems tried to be solved based on the fruiting bodies of fungi collected from ectomycorrhizal fungi picked from the areas contaminated by industrial emissions and areas free of contamination. The interaction of cadmium and lead ions on the growth of mycelium was examined by plate method and binding of heavy metals in fruiting structures of fungi were done by colorimetric method with use of methylene blue. It has been shown that the fungal resistance, even of the same species, to high concentration of heavy metals varies depending on the origin of symbiont. Isolated fungi from contaminated areas are better adapted to high concentrations of xenobiotics. Ability to bind cadmium and lead to fruiting bodies of fungi varies.