Effects of prebiotics on the gut microbiota in vitro associated with functional diarrhea in children

Diarrhea is one of the most common conditions in children, ranking among the top five causes of morbidity and mortality in this demographic. Gut microbial dysbiosis is one of the main risk factors for diarrhea, indicating that gut microbiota modulation may be an effective approach to preventing this condition. Most studies on prebiotic use in diarrhea have utilized animal or human adult subjects; however, in vivo studies on prebiotics can be confused by host–microbe interactions. As such, this study used an in vitro fermentation model to avoid this issue. Additionally, the effects of fructooligosaccharides (FOS) on the gut microbiota composition and metabolism in 39 children with functional diarrhea were investigated. 16S rRNA sequencing revealed that FOS significantly improved α- and β-diversity of gut microbiota in pediatric subjects, manifesting in increased probiotic bacteria, including Bifidobacterium, and significant inhibition of harmful bacteria, including Escherichia-Shigella. FOS also decreased the levels of isobutyric acid, isovaleric acid, ammonia, and hydrogen sulfide, which positively correlated with the relative abundance of Lachnoclostridium and negatively correlated with the abundance of Streptococcus. These findings suggest that FOS can modulate the gut microbiota in children with functional diarrhea and potentially provide an alternative to antibiotics for diarrhea treatment. 

Key takeaways:

• Functional diarrhea is a common condition in children, often caused by disturbances in the gut microbial composition and alterations in bacterial metabolites.
• Prebiotics, such as FOS, may alleviate the symptoms of functional diarrhea in children by modulating the gut microbiota composition and promoting the growth of beneficial bacteria and intestinal barrier integrity. 
• This study supports FOS use as a potential therapeutic option for managing functional diarrhea and its induced disturbances in the gut microbiota.

Access the study: https://pubmed.ncbi.nlm.nih.gov/37720150/ 

Reference: Du, Z., Li, J., Li, W., Fu, H., Ding, J., Ren, G., Zhou, L., Pi, X., & Ye, X. (2023). Effects of prebiotics on the gut microbiota in vitro associated with functional diarrhea in children. Frontiers in microbiology, 14, 1233840. https://doi.org/10.3389/fmicb.2023.1233840

The effects of synbiotics supplementation on reducing chemotherapy-induced side effects in women with breast cancer: a randomized placebo-controlled double-blind clinical trial

Breast cancer (BC) is the most frequent disease affecting women worldwide and the main cause of mortality in females aged 20-50 years. Chemotherapy is the main form of treatment for BC patients, targeting and killing cancer cells. However, it may inevitably harm normal cells, including intestinal epithelial and microbial cells, causing intestinal and non-intestinal complications, and reducing patient’s quality of life. This randomized, double-blind, placebo-controlled clinical trial aimed to evaluate the effects of oral intake of synbiotic supplements on common chemotherapy-induced complications in BC patients, including nausea/vomiting, defecation problems, fatigue, pain, sleep quality, anorexia, and mental status. Sixty-seven women diagnosed with BC and hospitalized to receive a one-day chemotherapy session randomly received either the synbiotic supplement containing 21 g of FOS and 12 probiotic strains at a dose of 1 × 109 CFU (Lactobacillus rhamnosus, Lactobacillus casei, Lactobacillus acidophilus, Lactobacillus bulgaricus, Bifidobacterium breve, Bifidobacterium longum, Lactobacillus helveticus, Lactobacillus lactis, Lactobacillus paraplantarum, Bifidobacterium bifidum, Streptococcus thermophilus and Lactobacillus gasseri) or the placebo twice a day for eight weeks. Eight weeks after the intervention and confounders (protein, fat, fiber, calcium, and vitamin C intake) adjustment, a significant decrease was observed for both the abnormal defecation and fatigue in the severity of chemotherapy complications in the synbiotic group compared to the placebo group. Furthermore, both nausea/vomiting and anorexia decreased compared to baseline but showed no significance compared to the placebo group. As such, synbiotic supplementation may potentially reduce fatigue and abnormal defecation severity during chemotherapy and reduce anorexia and nausea/vomiting in BC patients. 

Key takeaways:

• Breast cancer is the most common malignancy and a leading cause of death among women worldwide.
• Chemotherapy is the most common form of treatment for BC involving cytotoxic agent use to target and kill cancer cells, causing various side effects as it impacts normal cells and tissues.
• Synbiotic supplements may reduce the common chemotherapy-induced side effects in BC patients. 
• This study revealed that eight weeks of synbiotic supplementation may be beneficial as an adjuvant treatment for reducing the severity of common chemotherapy-induced side effects in BC patients.

Access the study: https://pubmed.ncbi.nlm.nih.gov/37752516/ 

Reference: Khazaei, Y., Basi, A., Fernandez, M. L., Foudazi, H., Bagherzadeh, R., & Shidfar, F. (2023). The effects of synbiotics supplementation on reducing chemotherapy-induced side effects in women with breast cancer: a randomized placebo-controlled double-blind clinical trial. BMC complementary medicine and therapies, 23(1), 339. https://doi.org/10.1186/s12906-023-04165-8

Resistant starch decreases intrahepatic triglycerides in patients with NAFLD via gut microbiome alterations

Non-alcoholic fatty liver disease (NAFLD) is a multisystem disease that has reached epidemic proportions globally, affecting 30% of the world’s population. NAFLD may develop into severe chronic hepatic conditions and contribute to extrahepatic diseases such as type 2 diabetes, cardiovascular disease, and chronic kidney disease. Nonetheless, effective interventions for NAFLD patients are still lacking. This randomized, double-blinded, placebo-controlled study investigated the effects of resistant starch (RS) supplementation on reducing intrahepatic triglycerides content (IHTC) in NAFLD patients by altering the gut microbiome. One hundred NAFLD patients were randomized to receive either the placebo (corn starch) or 40 g/day of high-amylose maize RS type 2 (HAM-RS2) for four months. The primary outcome was the change in IHTC while the secondary outcomes included changes in the anthropometric indicators, body composition, glycemic control and insulin sensitivity, liver and renal function, lipid profiles, cytokines, multi-omic parameters, single nucleotide polymorphisms, and NAFLD remission rate. The results showed that RS intervention led to a 9.08% absolute reduction of IHTC (5.89% after adjusting for weight loss), which was significantly correlated with a reduction in serum branched-chain amino acids (BCAAs) and gut microbial species, specifically Bacteroides stercoris, and liver enzymes. As such, RS dietary supplementation may be used as a strategy for NAFLD management that alters gut microbiota composition and functionality. 

Key takeaways:

• NAFLD is a hepatic and extrahepatic condition that causes tremendous clinical and economic burden worldwide, with patients lacking effective treatment therapies.
• RS can potentially be used as a gut microbiota-directed dietary supplement to treat NAFLD.
• Four months of HAM-RS2 dietary supplementation may be effective in NAFLD management by altering the gut microbial composition and functionality.

Access to the study: https://pubmed.ncbi.nlm.nih.gov/37673036/ 

Reference: Ni, Y., Qian, L., Siliceo, S. L., Long, X., Nychas, E., Liu, Y., Ismaiah, M. J., Leung, H., Zhang, L., Gao, Q., Wu, Q., Zhang, Y., Jia, X., Liu, S., Yuan, R., Zhou, L., Wang, X., Li, Q., Zhao, Y., El-Nezami, H., … Jia, W. (2023). Resistant starch decreases intrahepatic triglycerides in patients with NAFLD via gut microbiome alterations. Cell metabolism, 35(9), 1530–1547.e8. https://doi.org/10.1016/j.cmet.2023.08.002

Effect of synbiotic supplementation on immune parameters and gut microbiota in healthy adults: a double-blind randomized controlled trial

There is a constant interaction between the host immune system and the gut microbiota, maintaining homeostasis and normal physiological functions. As such, implementing gut-microbiota-targeting therapies may regulate immune function and infection susceptibility. Synbiotics are mixtures of live organisms and substrates that can modulate the gut microbiota but have limited evidence concerning their immunomodulatory effects in healthy individuals. This randomized, double-blinded, placebo-controlled study enrolled 106 healthy adults to receive either a synbiotic mixture with 500 mg/d FOS and 1.5 x 108 CFU/d Bifidobacterium lactis HN019, 7.5 x 107 CFU/d Lactobacillus rhamnosus HN001, or placebo for eight weeks. Immune parameters and gut microbial composition were measured at the baseline, mid, and end of the study. Synbiotic supplementation resulted in a significant reduction in interferon-gamma and a significant increase in plasma interleukin (IL)-10 and stool secretory IgA (sIgA), as well as an enrichment in beneficial bacteria, including Clostridium_sensu_stricto_1, Lactobacillus, Bifidobacterium, and Collinsella, with a reduced potential pro-inflammatory Parabacteroides. Notably, the reduction in the anti-inflammatory markers, including IL-10 and sIgA, was significantly correlated with the microbial changes triggered by the synbiotic supplementation. In conclusion, this study demonstrated some beneficial effects of synbiotics on the immune parameters, which also were correlated with the synbiotic-induced microbial changes and enterotypes, supporting the use of synbiotics for personalized immunomodulation.

Key takeaways:

• The gut microbiota interacts with the host’s immune system, managing its homeostasis and normal physiological function.
• Synbiotics are gaining interest as microbiota-targeting therapies for their potential positive effect on immunity.
• This study revealed that eight weeks of synbiotic supplementation positively contributed to the gut microbial composition and immune parameters, showing synbiotics as potential tools for use in immunomodulation. 

Access to the study: https://pubmed.ncbi.nlm.nih.gov/37614109/ 

Reference: Li, X., Hu, S., Yin, J., Peng, X., King, L., Li, L., Xu, Z., Zhou, L., Peng, Z., Ze, X., Zhang, X., Hou, Q., Shan, Z., & Liu, L. (2023). Effect of synbiotic supplementation on immune parameters and gut microbiota in healthy adults: a double-blind randomized controlled trial. Gut microbes, 15(2), 2247025. https://doi.org/10.1080/19490976.2023.2247025