Supplementation of Heat-Treated Lactiplantibacillus plantarum nF1 Changes the Production of Short-Chain Fatty Acids in Healthy Infants.

Background: Imbalance of the gut microbiome and decrease in the number of short-chain fatty acid (SCFA)-producing bacteria often affect human health by altering intestinal and immune homeostasis. The use of probiotics has been shown to be an attractive method to modulate gut microbiota to prevent or treat intestinal dysbiosis. Likewise, this study aimed to determine whether the oral consumption of heat-treated Lactiplantibacillus plantarum nF1 (HLp-nF1) induces changes in the gut environment in healthy infants by measuring changes in fecal SCFAs. Methods: The study enrolled 43 infants aged under 2 months, with 30 infants in the HLp-nF1 group receiving HLp-nF1 orally (2.5 × 1010 cells/g/pack, daily dose of two packs) for 8 weeks. The fecal samples were collected and the questionnaires were administered at weeks 0 and 8. Results: The concentrations of the total SCFAs, acetate, propionate, and butyrate significantly increased following HLp-nF1 supplementation (P < 0.0001, P < 0.0001, P < 0.0001, and P=0.028, respectively). Conclusions: Supplementation of HLp-nF1 has a positive effect on SCFA production and could be a potentially useful and straightforward method to manipulate SCFA formation.

Effect of Heat-Treated Lactiplantibacillus plantarum nF1 on the Immune System Including Natural Killer Cell Activity: A Randomized, Placebo-Controlled, Double-Blind Study.

Heat-treated Lactiplantibacillus plantarum nF1 (HT-nF1) increases immune cell activation and the production of various immunomodulators (e.g., interleukin (IL)-12) as well as immunoglobulin (Ig) G, which plays an important role in humoral immunity, and IgA, which activates mucosal immunity. To determine the effect of HT-nF1 intake on improving immune function, a randomized, double-blind, placebo-controlled study was conducted on 100 subjects with normal white blood cell counts. The HT-nF1 group was administered capsules containing 5 × 1011 cells of HT-nF1 once a day for 8 weeks. After 8 weeks of HT-nF1 intake, significant changes in IL-12 were observed in the HT-nF1 group (p = 0.045). In particular, the change in natural killer (NK) cell activity significantly increased in subjects with low secretory (s) IgA (≤49.61 µg/mL) and low NK activity (E:T = 10:1) (≤3.59%). These results suggest that HT-nF1 has no safety issues and improves the innate immune function by regulating T helper (Th)1-related immune factors. Therefore, we confirmed that HT-nF1 not only has a positive effect on regulating the body's immunity, but it is also a safe material for the human body, which confirms its potential as a functional health food ingredient.

Anticancer Effects of Washed-Dehydrated Solar Salt Doenjang on Colon Cancer-Induced C57BL/6 Mice.

This study researched the mineral composition of Korean washed-dehydrated solar salt (WDS) without bittern. It also evaluated the anticancer effects of doenjang (WDSD) prepared using WDS on azoxymethane (AOM)/dextran sodium sulfate (DSS)-induced colon cancer in C57BL/6 mice. The mineral composition of WDS showed lower Mg (11.71 ± 1.89 g/kg) and S (9.77 ± 2.88 g/kg) contents, and it was confirmed that mice in the WDSD group (AOM/DSS+WDSD) displayed significantly lower weight loss, colon length reduction, and tumor formation compared with the control (Con) group. In addition, pathologically, it was confirmed that the extent of epithelial cell damage and inflammation in the colon tissue of the WDSD group was restored to a state similar to that of the Nor group. Besides, WDSD regulated the protein expression of apoptosis (Bcl-2-associated X protein [Bax], B cell lymphoma-2 [Bcl-2], B cell lymphoma-extra large [Bcl-xL], and caspase 9, caspase 3), and p53, p21, and proinflammatory cytokines (interleukin [IL]-6, tumor necrosis factor [TNF]-α), thereby inducing the apoptosis and cell cycle arrest of cancer cells and suppressing inflammation. In addition, the intestinal microbiota of the mice treated with WDSD were more diverse, with an abundance of Bifidobacterium, a lactic acid bacterium beneficial to colon health, was also a greater presence of Faecalibaculum, which showed antitumor effects. These results indicate that solar salts and their different processing methods affect their functional health-promoting properties. In addition, the inhibitory effect on colon cancer was further enhanced when doenjang was prepared with WDS with low Mg and S content.

Catechin with Lactic Acid Bacteria Starters Enhances the Antiobesity Effect of Kimchi.

The antiobesity effects of kimchi with catechin and lactic acid bacteria as starters were studied in C57BL/6 mice with high-fat diet (HFD)-induced obesity. We prepared four types of kimchi: commercial kimchi, standard kimchi, green tea functional kimchi, and catechin functional kimchi (CFK). Body weight and weight of adipose tissue were significantly lower in the kimchi-treated groups than in the HFD and Salt (HFD +1.5% NaCl) groups. In addition, in the CFK group, the serum levels of triglycerides, total cholesterol, and low-density lipoprotein cholesterol were significantly lower and those of high-density lipoprotein cholesterol were markedly higher than the corresponding levels in the HFD and Salt groups. Moreover, CFK reduced fat cells and crown-like structures in the liver and epididymal fat tissues. The protein expression of adipo/lipogenesis-related genes in the liver and epididymal fat tissues was significantly lower (1.90-7.48-fold) in the CFK group than in the HFD and Salt groups, concurrent with upregulation of lipolysis-related genes (1.71-3.38-fold) and downregulation of inflammation-related genes (3.17-5.06-fold) in epididymal fat tissues. In addition, CFK modulated the gut microbiomes of obese mice by increasing the abundance of Bacteroidetes (7.61%), while in contrast, Firmicutes (82.21%) decreased. In addition, the presence of the Erysipelotrichaceae (8.37%) family in the CFK group decreased, while the number of beneficial bacteria of the families, Akkermansiaceae (6.74%), Lachnospiraceae (14.95%), and Lactobacillaceae (38.41%), increased. Thus, CFK exhibited an antiobesity effect through its modulation of lipid metabolism and the microbiome.

The Campylobacter jejuni Type VI Secretion System Enhances the Oxidative Stress Response and Host Colonization.

The role of the Type VI secretion system (T6SS) in Campylobacter jejuni is poorly understood despite an increasing prevalence of the T6SS in recent C. jejuni isolates in humans and chickens. The T6SS is a contractile secretion machinery capable of delivering effectors that can play a role in host colonization and niche establishment. During host colonization, C. jejuni is exposed to oxidative stress in the host gastrointestinal tract, and in other bacteria the T6SS has been linked with the oxidative stress response. In this study, comparisons of whole genome sequences of a novel human isolate 488 with previously sequenced strains revealed a single highly conserved T6SS cluster shared between strains isolated from humans and chickens. The presence of a functional T6SS in the 488 wild-type strain is indicated by expression of T6SS genes and secretion of the effector TssD. Increased expression of oxidative stress response genes katA, sodB, and ahpC, and increased oxidative stress resistance in 488 wild-type strain suggest T6SS is associated with oxidative stress response. The role of the T6SS in interactions with host cells is explored using in vitro and in vivo models, and the presence of the T6SS is shown to increase C. jejuni cytotoxicity in the Galleria mellonella infection model. In biologically relevant models, the T6SS enhances C. jejuni interactions with and invasion of chicken primary intestinal cells and enhances the ability of C. jejuni to colonize chickens. This study demonstrates that the C. jejuni T6SS provides defense against oxidative stress and enhances host colonization, and highlights the importance of the T6SS during in vivo survival of T6SS-positive C. jejuni strains.