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Probiotics are defined as live organisms in the host that contribute to health benefits. Lactobacillus gasseri LM1065, isolated from human breast milk, was investigated for its probiotic properties based on its genome. Draft genome map and de novo assembly were performed using the PacBio RS II system and hierarchical genome assembly process (HGAP). Probiotic properties were determined by the resistance to gastric conditions, adherence ability, enzyme production, safety assessment and mobile genetic elements. The fungistatic effect and inhibition of hyphae transition were studied using the cell-free supernatant (CFS). L. gasseri LM1065 showed high gastric pepsin tolerance and mild tolerance to bile salts. Auto-aggregation and hydrophobicity were measured to be 61.21% and 61.55%, respectively. The adherence to the human intestinal epithelial cells was measured to be 2.02%. Antibiotic-resistance genes and putative virulence genes were not predicted in the genomic analysis, and antibiotic susceptibility was satisfied by the criteria of the European Food Safety Authority. CFS showed a fungistatic effect and suppressed the tricarboxylic acid cycle in Candida albicans (29.02%). CFS also inhibited the transition to true hyphae and damaged the blastoconidia. This study demonstrates the essential properties of this novel probiotic, L. gasseri LM1065, and potential to inhibit vaginal C. albicans infection., (© 2023. The Author(s).)

In this study, we explored whether the use of Streptococcus thermophilus LM1012 (TL-LM1012) as a safe probiotic exerts hepatoprotective effects by suppressing oxidative stress and inflammation in vitro and alleviating aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) production in vivo . In a series of safety tests, TL-LM1012 was found to have a negative response to hemolysis and biogenic amines, as well as susceptibility to antibiotics. TL-LM1012 protected cell viability and suppressed cytotoxicity by inhibiting oxidative stress and induced heme oxygenase-1 and superoxide dismutase activity in a dose-dependent manner in diesel exhaust particulate matter (DEPM)-treated HepG2 cells. Moreover, proinflammatory cytokines, including tumor necrosis factor- α , interleukin (IL)-6, and IL-1 β , were suppressed in DEPM-treated splenocytes. In DEPM-treated mice, oral administration of TL-LM1012 regulated AST, ALT, and LDH production in the serum after 14 days of treatment. These findings indicate that TL-LM1012, a safe probiotic, provides a potent preventive or therapeutic effect against liver disease caused by air pollution.

UVB irradiation can induce generation of reactive oxygen species (ROS) that cause skin aging or pigmentation. Lactobacillus acidophilus is a well-known probiotic strain that regulates skin health through antimicrobial peptides and organic products produced by metabolism and through immune responses. In this study, we investigated the antioxidative, antiwrinkle, and antimelanogenesis effects of tyndallized Lactobacillus acidophilus KCCM12625P (AL). To analyze the effects of AL on UV irradiation-induced skin wrinkle formation in vitro, human keratinocytes and human dermal fibroblasts were exposed to UVB. Subsequent treatment with AL induced antiwrinkle effects by regulating wrinkle-related genes such as matrix metalloproteinases (MMPs), SIRT-1, and type 1 procollagen (COL1AL). In addition, Western blotting assays confirmed that regulation of MMPs by AL in keratinocytes was due to regulation of the AP-1 signaling pathway. Furthermore, we confirmed the ability of AL to regulate melanogenesis in B16F10 murine melanoma cells treated with α-melanocyte-stimulating hormone ( α -MSH). In particular, AL reduced the mRNA expression of melanogenesis-related genes such as tyrosinase, TYRP-1, and TYRP-2. Finally, we used Western blotting assays to confirm that the antimelanogenesis role of AL was due to its regulation of the cyclic adenosine monophosphate (cAMP) signaling pathway. Collectively, these results indicate that AL has an antiwrinkle activity in damaged skin and can inhibit melanogenesis. Thus, AL should be considered an important substance for potential use in anti-aging drugs or cosmetics.

A rise in the occurrence of allergic diseases is attributed to the dysregulated balance of type 1/type 2 immunity, where type 2 T-helper (Th2) cells predominate over type 1 T-helper (Th1) cells, leading to an abnormally increased production of IgE in response to unharmful antigens. Kimchi, a traditional Korean fermented food, is a rich source of beneficial lactic acid bacteria. In this study, we investigated the ability of Enterococcus faecium FC-K derived from kimchi to induce type I immunity in the presence of Th2 polarizing conditions in vitro and in vivo. Stimulation of mouse peritoneal macrophages with E. faecium FC-K induced the production of tumor necrosis factor alpha, interleukin (IL)-6, and IL-12. Under the in vitro Th2 conditions in which splenic T cells were activated in the presence of IL-4, E. faecium FC-K enhanced the ability of T cells to produce interferon (IFN)-γ. Using the ovalbumin (OVA)-induced allergy model, male BALB/c mice receiving E. faecium FC-K reduced the serum level of total IgE, but not that of OVA-specific IgE. Furthermore, the population of activated splenic B cells during OVA immunization was decreased in E. faecium FC-K-treated mice, accounting for a reduction of total IgE in the serum. Restimulating splenocytes from OVA-immunized mice with OVA ex vivo resulted in an increased production of IFN-γ, with no effect on IL-4, in E. faecium FC-Ktreated mice. These observations provide the evidence that E. faecium FC-K can be a beneficial probiotic strain that can modulate the Th2-mediated pathologic response.

Skin is the soft outer covering of vertebrates that provides protection from pathogenic infection, physical damage, or UV irradiation, and controls body temperature and water content. In this study, we examined the effects of oral intake of kimchi-derived Lactobacillus plantarum K8 lysates on skin moisturizing. In an in vitro study, we observed that the hyaluronic acid content increased in HaCaT cells treated with L. plantarum K8 lysates. Oral administration of L. plantarum K8 lysates effectively attenuated the horny layer formation and decreased epidermal thickening in DNCB-treated SKH-1 hairless mice skin. The damage to barrier function was reduced after 8 weeks of oral administration of L. plantarum K8 lysates as compared with that in the atopic dermatitis mice. For the test with volunteers, we manufactured experimental candy containing 2.1% L. plantarum K8 lysates, while control candy did not contain bacterial lysate. A significant increase in hydration in the experimental candy-administered group as compared with the control candy-administered group was observed on the face after 4 and 8 weeks, and on the forearm after 4 weeks. Decreases in horny layer thickness and TEWL value were observed on the face and forearm of the experimental group. Together, the in vitro cell line and in vivo mouse studies revealed that L. plantarum K8 lysates have a moisturizing effect. A clinical research study with healthy volunteers also showed an improvement in barrier repair and function when volunteers took L. plantarum K8 lysates-containing candy. Thus, our results suggest that L. plantarum K8 lysates may help to improve skin barrier function.

Probiotics, including Lacticaseibacillus rhamnosus (L. rhamnosus), have gained recognition for their potential health benefits, such as enhancing immune function, maintaining gut health, and improving nutrient absorption. This study investigated the effectiveness of L. rhamnosus LM1019 (LM1019) in enhancing immune function. In RAW 264.7 cells, LM1019 demonstrated dose-dependent immune stimulation by increasing nitric oxide production, gene expression of proinflammatory cytokines, and the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). These effects were mediated through the activation of mitogen-activated protein kinases (MAPKs) and nuclear factor-kappa B (NF-κB) translocation without inducing cytotoxicity. Furthermore, orally administered LM1019 was evaluated in immunosuppressed mice induced by cyclophosphamide (CTX). High-dose administration of LM1019 significantly increased the subpopulations of lymphocytes, specifically helper T cells (CD4+), as well as two subtypes of natural killer (NK) cells, namely, IFN-γ+ and granzyme B+ NK cells. Additionally, LM1019 at a high dose led to elevated levels of proinflammatory cytokines, including IFN-γ and IL-12, compared to CTX-treated mice. These findings highlight the potential of LM1019 in enhancing the immune system. The study contributes to the growing body of research on the beneficial effects of probiotics on immune function. [ABSTRACT FROM AUTHOR]

Although leaky gut syndrome is not recognized as an official diagnosis for human diseases, it is now believed that dysfunction of the cell barrier causes increased permeability of intestinal epithelial cells leading to this condition. Probiotics have been widely used to improve gut health, and studies have investigated the relevance of protecting the intestinal barrier by taking probiotic strains in vitro and in vivo. However, most studies have restricted the use of single or several probiotic strains and do not consider commercially available probiotic products composed of multi-species. In this study, we provide experimental evidence that a multi-species probiotic mixture composed of eight different strains and a heat-treated probiotic strain is effective in preventing leaky gut conditions. We employed an in vitro co-culture model system utilizing two different differentiated cell lines to mimic human intestinal tissue. The integrity of epithelial barrier function was protected by the preserving the occludin protein level and activating the AMPK signaling pathway, associated with tight junctions (TJs), through treatment with the probiotic strain mixture in Caco-2 cells. Moreover, we confirmed that application of the multi-species probiotic mixture reduced the expression of proinflammatory cytokine genes by inhibiting NFκB signaling pathway when artificial inflammation was induced in an in vitro co-culture model system. Finally, we proved that the epithelial permeability measured by trans-epithelial electrical resistance (TEER) was significantly decreased in the probiotic mixture treated cells, indicating that the integrity of the epithelial barrier function was not compromised. The multi-species probiotic strain mixture exhibited the protective effect on the integrity of intestinal barrier function via enhancing TJ complexes and reducing inflammatory responses in the human intestinal cells. [ABSTRACT FROM AUTHOR]

[Display omitted] • Supplementation with heat-treated Lactobacillus plantarum LM1004 (HT-LM1004) for eight weeks activated the innate immunity in healthy adults. • Natural killer cells were enhanced with HT-LM1004 compared to the control group. • Serum level of interleukin-12 by dietary intake of HT-LM1004 was elevated from baseline. • Treatment of HT-LM1004 was safe and well tolerated. Heat-treated Lactobacillus plantarum LM1004 (HT-LM1004) isolated from Korean kimchi and further processed has been reported to exert the stimulatory activities on the innate immune system in our previous in vitro and in vivo studies. The aim of the present study was to examine the effect of HT-LM1004 on changes in natural killer (NK) cell activity, the serum concentrations of cytokines and safety parameters in healthy adults aged 19–75 years. In the present randomized, placebo-controlled, double-blind trial, one hundred subjects consumed a capsule containing 2 × 1010 cells of HT-LM1004 or placebo once per day over eight weeks. Significant increases in NK cell activity (%) were observed in the treatment group after eight weeks of HT-LM1004 ingestion compared to the control group (p = 0.036). This study also demonstrated a consistent trend of enhanced serum level of interleukin (IL)-12 by dietary intake of HT-LM1004 without any side effects. [ABSTRACT FROM AUTHOR]