Effect of Lactobacillus strains on thymus and chemokine expression in keratinocytes and development of atopic dermatitis-like symptoms

Lactobacillus for the treatment and prevention of atopic dermatitis: Clinical and experimental evidence

Atopic dermatitis (AD) is a chronic inflammatory skin disease, accompanied by itching and swelling. The main pathological mechanism of AD is related to the imbalance between Type 2 helper cells (Th2 cells) and Type 1 helper cells (Th1 cells). Currently, no safe and effective means to treat and prevent AD are available; moreover, some treatments have side effects. Probiotics, such as some strains of Lactobacillus, can address these concerns via various pathways: i) facilitating high patient compliance; ii) regulating Th1/Th2 balance, increasing IL-10 secretion, and reducing inflammatory cytokines; iii) accelerating the maturation of the immune system, maintaining intestinal homeostasis, and improving gut microbiota; and iv) improving the symptoms of AD. This review describes the treatment and prevention of AD using 13 species of Lactobacillus. AD is commonly observed in children. Therefore, the review includes a higher proportion of studies on AD in children and fewer in adolescents and adults. However, there are also some strains that do not improve the symptoms of AD and even worsen allergies in children. In addition, a subset of the genus Lactobacillus that can prevent and relieve AD has been identified in vitro. Therefore, future studies should include more in vivo studies and randomized controlled clinical trials. Given the advantages and disadvantages mentioned above, further research in this area is urgently required.

ANTIMICROBIAL POTENTIAL OF LACTIC ACID BACTERIA LACTOBACILLUS RHAMNOSUS LYSATE

According to World Health Organization, antibiotic resistance is rising to dangerously high levels in all parts of the world. New resistance mechanisms are emerging and spreading globally, threatening our ability to treat common infectious diseases. Therefore, searching for new antimicrobial agents of natural origin is an extraordinary global problem. The work aimed to determine the antimicrobial activity of lyophilized enzymatic lysate of cells of the Lactobacillus rhamnosus V strain of lactic acid bacteria. The object of the study was the drug Del-Imun V®, which hasanti-allergican dimmuno stimulating activity. The researchers' efforts aimed to fully reveal the drug's potential, particularlyitsanti microbialaction. Antimicrobial activity was determined by the minimum inhibitory concentration (MIC). Determination of MIC was carried out by the method of twotime serial dilutions in meat-peptone broth (MPB) for bacteria and liquid wort for yeast. Gram-negative (Escherichia coli IEM-1, Proteus vulgaris PA-12, Pseudomonas sp. MI-2) and Gram-positive (Bacillus subtilis BТ-2, Staphylococcus aureus BМС-1) bacteria, as well as yeast (Candida albicans D-6, Candida tropicalis PE-2, Candida utilis BVS-65). It was shown that MIC valuesof the native preparation for the bacterial test cultures (EscherichiacoliIEM-1, Bacillussubtilis BT-2, Staphylococcusaureus BMS-1, Proteusvulgaris PA-12, Pseudomonassp. MI-2) were 8 time slower, than those of the thermally in activated preparation, forthe yeasts (Candidaalbicans D-6, Candidatropicalis PE-2, Candidautilis BVS-65) – 4-8 time slower. As a result of the conducted research, the antibacterial and antifungal activity of the drugDel-Imun V® was established. The spectrum of antimicrobial activity concerned gram-positiveand gram-negative bacteria and yeast-like fungi of the genus Candida. The minimum inhibitory concentrations were quite low: from 1.0 to 4.0 μg/ml for bacterial cultures and from 62.5 to 125 μg/ml for yeast. The culture of B. subtilis BT-2 was the least sensitive to the drug's action (MIC – 12.5 μg/ml). There fore, it can be concluded that the lysate of Lactobacillus rhamnosus V lacticacid bacteriahasanti bacteria landanti fungal properties.

Anti-Inflammatory Effects of Metabolites from Antarctic Fungal Strain Pleosporales sp. SF-7343 in HaCaT Human Keratinocytes

Chemical investigation of the Antarctic fungi Pleosporales sp. SF-7343 revealed four known secondary fungal metabolites: alternate C (1), altenusin (2), alternariol (3), and altenuene (4). The compound structures were identified primarily by NMR and MS analyses. Atopic dermatitis, an inflammatory disease, is driven by the abnormal activation of T helper (Th) 2 cells and barrier dysfunction. We attempted to identify the anti-inflammatory components of SF-7343. Initial screening showed that compounds 1 and 3 inhibited the secretion of interleukin-8 and -6 in tumor necrosis factor-α/interferon-γ-treated HaCaT cells, and these compounds also showed inhibitory effects on CCL5 and CCL22. Compounds 1 and 3 also downregulated the protein expression levels of intercellular adhesion molecule-1 and upregulated the expression of filaggrin and involcurin. The mechanism study results showed that compounds 1 and 3 inhibited nuclear translocation of nuclear factor-kappa B p65 and the phosphorylation of STAT1 and STAT3. Compound 1, but not compound 3, significantly promoted the expression of heme oxygenase (HO)-1. The effects of compound 1 were partly reversed by co-treatment with a HO-1 inhibitor, tin protoporphyrin IX. Taken together, this study demonstrates the potential value of Antarctic fungal strain SF-7343 isolates as a bioresource for bioactive compounds to prevent skin inflammation.