A Spore-Forming Probiotic Supplement Improves the Intestinal Immune Response and Protects the Intestinal Health During Recurrent Clostridioides difficile Colonization in Mice

Functional Muffins Exert Bifidogenic Effects along with Highly Product-Specific Effects on the Human Gut Microbiota Ex Vivo

GoodBiome™ Foods are functional foods containing a probiotic (Bacillus subtilis HU58™) and prebiotics (mainly inulin). Their effects on the human gut microbiota were assessed using ex vivo SIFR® technology, which has been validated to provide clinically predictive insights. GoodBiome™ Foods (BBM/LCM/OSM) were subjected to oral, gastric, and small intestinal digestion/absorption, after which their impact on the gut microbiome of four adults was assessed (n = 3). All GoodBiome™ Foods boosted health-related SCFA acetate (+13.1/14.1/13.8 mM for BBM/LCM/OSM), propionate (particularly OSM; +7.4/7.5/8.9 mM for BBM/LCM/OSM) and butyrate (particularly BBM; +2.6/2.1/1.4 mM for BBM/LCM/OSM). This is related to the increase in Bifidobacterium species (B. catenulatum, B. adolescentis, B. pseudocatenulatum), Coprococcus catus and Bacteroidetes members (Bacteroides caccae, Phocaeicola dorei, P. massiliensis), likely mediated via inulin. Further, the potent propionogenic potential of OSM related to increased Bacteroidetes members known to ferment oats (s key ingredient of OSM), while the butyrogenic potential of BBM related to a specific increase in Anaerobutyricum hallii, a butyrate producer specialized in the fermentation of erythritol (key ingredient of BBM). In addition, OSM/BBM suppressed the pathogen Clostridioides difficile, potentially due to inclusion of HU58™ in GoodBiome™ Foods. Finally, all products enhanced a spectrum of metabolites well beyond SCFA, including vitamins (B3/B6), essential amino acids, and health-related metabolites such as indole-3-propionic acid. Overall, the addition of specific ingredients to complex foods was shown to specifically modulate the gut microbiome, potentially contributing to health benefits. Noticeably, our findings contradict a recent in vitro study, underscoring the critical role of employing a physiologically relevant digestion/absorption procedure for a more accurate evaluation of the microbiome-modulating potential of complex foods.

Antimicrobial Activity of Tannic Acid In Vitro and Its Protective Effect on Mice against Clostridioides difficile

Clostridioides difficile infection (CDI), recurrently reported as an urgent threat owing to its increased prevalence and mortality, has attracted significant attention. As the use of antibiotics to treat CDI has many limitations, such as high recurrence rate, the need to actively seek and develop other drugs that can effectively treat CDI with fewer side effects has become a key issue in CDI prevention and treatment. This study aimed to evaluate the inhibitory effect of Galla chinensis (GC) and its main component, tannic acid (TA), against C. difficile in vitro and its therapeutic effect on CDI in vivo. When GC and TA concentrations were 250 and 64 mg/L, respectively, the cumulative antibacterial rate against C. difficile reached 100%. The sub-MIC of TA significantly inhibited C. difficile sporulation, toxin production, and biofilm formation in vitro. Compared with the CDI control group, TA-treated mice lost less weight and presented a significantly improved survival rate. TA significantly reduced the number of spores in feces, decreased serum TcdA level, and increased serum interleukin 10 (IL-10). Based on the inhibitory effect of TA on C. difficile in vitro and its therapeutic effect on the CDI mouse model, we consider TA as a potentially effective drug for treating CDI. IMPORTANCE Clostridioides difficile is one of the major pathogens to cause antibiotic-associated diarrhea. Although antibiotic treatment is still the most commonly used and effective treatment for CDI, the destruction of indigenous intestinal microbiota by antibiotics is the main reason for the high CDI recurrence rate of about 20%, which is increasing every year. Moreover, the growing problem of drug resistance has also become a major hidden danger in antibiotic treatment. GC has been used to treat diarrhea in traditional Chinese medicine. In the present study, we evaluated the inhibitory effect of TA, the main component of GC, on dissemination and pathogenic physiological functions of C. difficile in vitro, as well as its therapeutic efficacy in a CDI model. Overall, TA is considered to be a potentially effective drug for CDI treatment.

Targeting the Gut Microbiota and Host Immunity with a Bacilli-Species Probiotic during Antibiotic Exposure in Mice

Antibiotic therapy is necessary for the treatment of bacterial infections; however, it can also disrupt the balance and function of commensal gut microbes and negatively affect the host. Probiotics have been tested as a means to counteract the negative effects of antibiotic therapy, but many probiotics are also likely destroyed by antibiotics when taken together. Here we aimed to test the efficacy of a non-pathogenic spore-forming Bacillus-species containing a probiotic blend provided during antibiotic therapy on host immune defenses in mice. Mice were exposed to antibiotics and supplemented with or without the probiotic blend and compared to control mice. Fecal and cecal contents were analyzed for gut microbes, and intestinal tissue was tested for the expression of key enzymes involved in vitamin A metabolism, serum amyloid A, and inflammatory markers in the intestine. The probiotic blend protected against antibiotic-induced overgrowth of gram-negative bacteria and gammaproteobacteria in the cecum which correlated with host immune responses. Regional responses in mRNA expression of enzymes involved with vitamin A metabolism occurred between antibiotic groups, and intestinal inflammatory markers were mitigated with the probiotic blend. These data suggest prophylactic supplementation with a spore-forming Bacillus-containing probiotic may protect against antibiotic-induced dysregulation of host immune responses.