Anti-inflammatory and anti-pathogenic potential of Lacticaseibacillus rhamnosus IDCC 3201 isolated from feces of breast-fed infants.

OBJECTIVE: We investigated the anti-inflammatory and anti-pathogenic activities of Lacticaseibacillus rhamnosus IDCC 3201 isolated from the feces of breast-fed infants. METHODS: Cell viability, nitric oxide (NO) production, and expression of inflammatory markers by L. rhamnosus IDCC 3201 were quantitatively analyzed in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. The antibacterial and antifungal activities of L. rhamnosus IDCC 3201 against various pathogens were also investigated. RESULTS: Treatment of LPS-induced macrophages with cell-free supernatant of L. rhamnosus IDCC 3201 significantly decreased the expression levels of tumor necrosis factor (TNF-α) and interleukin-6 (IL-6). Nitric oxide synthase (iNOS) and cyclooxygenase (COX-2) levels also significantly decreased in LPS-induced macrophages. Phenotypically, the treatment of L. rhamnosus IDCC 3201 reduced the production of nitric oxide (NO) in LPS-induced macrophages. Furthermore, L. rhamnosus IDCC 3201 was proven to have potent inhibitory activities against various pathogens responsible for inflammatory responses in the gastrointestinal tract (i.e., Bacillus cereus, Enterococcus faecalis, Staphylococcus aureus, and Salmonella Typhimurium), respiratory system (i.e., Streptococcus pneumoniae), and vagina (i.e., Candida albicans). CONCLUSION: L. rhamnosus IDCC 3201 has anti-inflammatory activity in terms of decreased expression of cytokines, inflammation-inducible enzymes in LPS-induced macrophages, and anti-pathogenic activity.

Safety evaluation and anti-inflammatory activity of Lactobacillus johnsonii IDCC 9203 isolated from feces of breast-fed infants.

This study evaluated the safety of Lactobacillus johnsonii IDCC 9203 and investigated its anti-inflammatory activity in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. Genomic analysis revealed that this strain has no virulence and antibiotic resistance gene except tetW, which is a tetracycline resistance gene. Minimum inhibitory concentration data showed that the strain is resistant to tetracycline and aminoglycosides. Further analysis indicated that the transferability of the tetW gene is extremely low, and resistance to aminoglycosides is due to the intrinsic resistance of L. johnsonii IDCC 9203. Phenotypic safety assessment showed that the strain has neither ß-hemolytic nor ß-glucuronidase activity, and no biogenic amine production. When LPS-induced RAW 264.7 cells were treated with L. johnsonii IDCC 9203, the level of nitric oxide and expression of pro-inflammatory cytokines significantly decreased (p < 0.05). Therefore, L. johnsonii IDCC 9203 strain is considered as safe and beneficial probiotic for human consumption.

Ochratoxin a induces hepatic fibrosis through TGF-ß receptor I/Smad2/3 signaling pathway.

Ochratoxin A (OTA) is a mycotoxin generated by Penicillium and Aspergillus species. It is often found in cereals. We hypothesized that OTA exposure induces epithelial-mesenchymal transition (EMT), leading to liver fibrosis. In this research, we explored whether the TGF-ß receptor I (TGF-ß RI)/Smad2/3 signaling pathway is related to EMT-induced hepatic fibrosis. In vitro and in vivo experiments, mRNA and protein expression of liver fibrosis-related markers such as fibronectin, α-smooth muscle actin (α-SMA) and E-cadherin were assessed. The levels of alkaline phosphatase, alanine transaminase, aspartate aminotransferase, and total bilirubin, which are used to assess damage, increased. We also confirmed the increase in mRNA and protein expression of TGF-ß RI, Smad2, and Smad3. The expression of liver fibrosis-related markers was decreased by siRNA-mediated silencing of Smad2/3, as well as TGF-RI suppression. Liver cells exposed to OTA showed enhanced TGF-ß RI expression on the cell membrane. These results demonstrated that OTA induces hepatic fibrosis through TGF-ß RI and Smad2/3 pathways in vitro and in vivo.

A Quadruple Coating of Probiotics for Enhancing Intestinal Adhesion and Competitive Exclusion of Salmonella Typhimurium.

Previously, our group showed that a quadruple coating of probiotics resulted in higher survivability of probiotics under high acid, bile salt, and thermal stresses. In this study, we evaluated the effect of the quadruple coating of probiotics on adhesive properties as well as on competitive exclusion of Salmonella Typhimurium in Caco-2 cells. We found that the quadruple coating of probiotics exhibited an overall increased adhesion property (up to 10.8-fold) and increased competitive exclusion of Salmonella Typhimurium (up to 4.3-fold). Thus, this study has significant implications and can lead to the development of methods that can improve the adhesive ability of probiotics as well as the adhesive inhibition of pathogens.

Anti-inflammatory potential of Lactiplantibacillus plantarum IDCC 3501 and its safety evaluation.

This study investigated the anti-inflammatory activity of Lactiplantibacillus plantarum IDCC 3501 isolated from kimchi (Korean fermented food) and its safety. When lipopolysaccharide (LPS)-induced RAW 264.7 macrophages were treated with cell-free supernatant from L. plantarum IDCC 3501, the mRNA expression level of inflammatory markers (i.e., TNF-α, IL-1ß, and IL-6) was significantly reduced. In addition, the decreased cell viability by LPS was recovered and NO production in LPS-induced cell was also decreased. For the safety assessment, the genes responsible for antibiotic resistance and virulence were not detected from the genome analysis of this strain. Consistent with this, minimal inhibitory concentrations against various antibiotics, biogenic amines, and D-lactate production, as well as enzymatic and hemolysis activities, indicated that L. plantarum IDCC 3501 did not produce any harmful compounds during fermentation. Furthermore, no acute toxicity and mortality were observed in a murine mouse model. Based on our findings, L. plantarum IDCC 3501 is safe and beneficial for human consumption.

Safety assessment of Streptococcus thermophilus IDCC 2201 used for product manufacturing in Korea.

Safety evaluation of probiotics has become increasingly important for human consumption in food industry. The aims of this study were to assess safety of Streptococcus thermophilus IDCC 2201 through in vitro and in vivo tests. In results, this strain was found to be negative for hemolytic and ß-glucuronidase activity. In addition, thermophilus IDCC 2201 was susceptible to nine antibiotics suggested by EFSA. In accordance with MIC tests, whole-genome analysis indicated that S. thermophilus IDCC 2201 neither harbors antibiotic resistance nor toxigenic genes. Furthermore, none of the biogenic amines including tyramine and histamine was produced and negligible amounts of D-lactate were produced by S. thermophilus IDCC 2201. Finally, it was confirmed that there was no mortality and toxicity throughout single-dose oral toxicity tests in rats. Therefore, we report that S. thermophilus IDCC 2201 is considered to be safe for human consumption as probiotics.

Ochratoxin A induces epithelial-to-mesenchymal transition and renal fibrosis through TGF-ß/Smad2/3 and Wnt1/ß-catenin signaling pathways in vitro and in vivo.

Ochratoxin A (OTA) is a toxin produced by fungi such as Aspergillus spp. and Penicillium spp. The key target organ of OTA toxicity is the kidney, and it is known that epithelial-to-mesenchymal transition (EMT) leading to fibrosis is enhanced after long-term exposure of the kidney to OTA. However, the mechanisms responsible for this onset are not precisely known. Therefore, the purpose of this study was to investigate the mechanism of OTA-induced EMT and fibrosis in human proximal tubule HK-2 cells and mouse kidneys. Cells were treated for 48 h with various concentrations of OTA (50, 100, and 200 nM) and mice underwent oral administration of various doses of OTA (200 and 1000 µg/kg body weight) for 12 weeks. Blood urea nitrogen and creatinine levels were increased in the serum of OTA-treated mice, and fibrosis was observed in kidney tissues. Furthermore, alpha-smooth muscle actin (α-SMA) and fibronectin levels were increased, and E-cadherin level was decreased by OTA in both HK-2 cells and kidney tissues. In addition, the expression levels of TGF-ß, smad2/3, and ß-catenin were increased after OTA treatment. α-SMA, E-cadherin, and fibronectin were shown to be regulated by the activation of transcription factors, smad2/3 and ß-catenin. These results demonstrated that OTA induces EMT and renal fibrosis through Smad2/3 and ß-catenin signaling pathways in vitro and in vivo.

Inhibitory Effect of Chebulic Acid on Alveolar Epithelial to Mesenchymal Transition in Response to Urban Particulate Matter Using Co-treatment and Post-treatment Exposure.

Urban particulate matter (UPM) is atmospheric particulate samples obtained from industrialized urban areas. It is known that pulmonary fibrosis can result directly or indirectly from particulate matter. In this study, the protective effect of chebulic acid (CA) against UPM-induced epithelial-mesenchymal transition (EMT) in the pulmonary alveolar epithelial (PAE) cells were investigated. Our findings revealed that PAE cells were changed from the epithelial phenotype to mesenchymal one after exposure to UPM. Furthermore, co-treatment and post-treatment of CA inhibited EMT progression. Especially the key epithelial marker, E-cadherin, was down-regulated by UPM and recovered by CA. Also, gelatin zymogram showed that the activity of matrix metalloproteinase (MMP)-2 and MMP-9 was decreased by co-treatment and post-treatment of CA. Further investigation revealed that CA attenuated UPM-stimulated PAE cells invasion ability. These data showed that UPM promoted PAE cells invasion, reactive oxygen species-mediated extracellular matrix degradation and CA reduced the potential health risks associated with UPM.