What’s the Latest in Prebiotic Research? February 2023 Edition
This monthly feature provides an overview of some of the latest studies on prebiotics. We’ll share key findings and insights from the studies. Have a study you’d like us to cover? Email GPA Communications Director Traci Kantowski email@example.com.
Probiotics, Prebiotics, and Synbiotics for Patients on Dialysis: A Systematic Review and Meta-Analysis of Randomized Controlled Trials
Chronic kidney disease (CKD) is estimated to affect 9.1% of the population worldwide with 0.041% requiring dialysis. Patients with CKD experience several inflammatory, nutritional, and metabolic complications, which can lead to the development of cardiovascular diseases. This systemic review and meta-analysis examined the effects of probiotic, prebiotic, and synbiotic administration on inflammation, metabolic parameters, nutritional status, and uremic toxins in dialysis patients. Relevant randomized controlled trials (RCTs) published before June 2021 were considered. Eighteen RCTs were selected with a total of 791 subjects, being either peritoneal dialysis or hemodialysis patients. The results showed that probiotics, prebiotics, and synbiotics could increase the levels of metabolic biomarkers such as high-density lipoprotein (HDL) cholesterol and decrease the levels of inflammatory biomarkers such as C-reactive protein (CRP) and interleukin 6 (IL-6), as well as uremic toxins like indoxyl sulfate. The results of this meta-analysis may have been influenced by participants as some differences occur in the intestinal microecology between peritoneal dialysis and hemodialysis patients. Therefore, to better examine the impact of probiotics, prebiotics, and synbiotics in dialysis patients, large-scale, long-term, controlled diets, and well-designed RCTs are required.
- Patients with CKD are subjected to inflammation, malnutrition, and metabolic complications, leading to cardiovascular diseases.
- Probiotic, prebiotic, and synbiotic supplements can slightly improve lipids and somewhat reduce inflammation and uremic toxins.
- Large-scale, long-term, well-designed RCTs are needed to better understand the effect of probiotics, prebiotics, and synbiotics in dialysis patients.
Access to the study: https://pubmed.ncbi.nlm.nih.gov/35452837/
Reference: Chen, C., Wang, J., Li, J., Zhang, W., & Ou, S. (2023). Probiotics, Prebiotics, and Synbiotics for Patients on Dialysis: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Journal of renal nutrition: the official journal of the Council on Renal Nutrition of the National Kidney Foundation, 33(1), 126–139. https://doi.org/10.1053/j.jrn.2022.04.001
A water-soluble tomato extract rich in secondary plant metabolites lowers trimethylamine-n-oxide and modulates gut microbiota: a randomized, double-blind, placebo-controlled cross-over study in overweight and obese adults
Natural products rich in polyphenols may lower plasma trimethylamine-n-oxide (TMAO) by modulating the intestinal microbiota. TMAO is derived from trimethylamine, a microbial metabolite produced by the gut microbiota generally from dietary components found in red meat, cheese, and eggs, and exhibits proinflammatory and proatherogenic properties. High baseline levels of TMAO have been linked to major adverse cardiovascular events. In this randomized, double-blind, placebo-controlled, cross-over clinical trial, the impact of Fruitflow, a water-soluble tomato extract, on plasma TMAO, fecal microbiota, concentrations of urine TMAO, and other fecal and plasma metabolites were investigated. Forty overweight and obese adults aged 35-65 years received 2 × 150 mg of Fruitflow per day or placebo (maltodextrin) for 4 weeks, with a 6-week washout between interventions. The results showed that Fruitflow, but not placebo, significantly reduced fasting levels of plasma and urine TMAO as well as plasma lipopolysaccharides (LPS) from baseline to the end of intervention. Moreover, plasma TMAO and LPS are recommended biomarkers of cardiometabolic risk and intestinal permeability and low-grade inflammation, respectively; hence, these effects can be considered host health benefits. Therefore, the results of this study reinforce earlier findings about the effect of polyphenol-rich extracts on lowering plasma TMAO in overweight and obese adults via modulation of the gut microbiota.
- Major adverse cardiovascular events may be experienced with high levels of TMAO.
- Fruitflow, a polyphenol-rich tomato extract, can lower TMAO concentration.
- The effect is thought to be via the modulatory action of polyphenols on the gut microbiota.
Access to the study: https://www.sciencedirect.com/science/article/pii/S0022316622131275
Reference: Rehman, A., Tyree, S. M., Fehlbaum, S., DunnGalvin, G., Panagos, C. G., Guy, B., Patel, S., Dinan, T. G., Duttaroy, A. K., Duss, R., & Steinert, R. E. (2022). A water-soluble tomato extract rich in secondary plant metabolites lowers trimethylamine-n-oxide and modulates gut microbiota: a randomized, double-blind, placebo-controlled cross-over study in overweight and obese adults. The Journal of Nutrition. https://doi.org/10.1016/j.tjnut.2022.11.009
Deficient butyrate-producing capacity in the gut microbiome is associated with bacterial network disturbances and fatigue symptoms in ME/CFS
Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is an unexplained debilitating and chronic disease, which includes fatigue, post-exertional malaise, impaired memory, pain, gastrointestinal disturbances, immune abnormalities, and sleep disruptions. Various studies have established differences in the gut microbiome in the form of dysbiosis between ME/CFS patients and healthy individuals. In this prospective case-control study, shotgun metagenomics and metabolomics of fecal samples were used to assess dysbiosis in 106 ME/CFS subjects and 91 matched healthy controls. The multi-omic analysis revealed differences in gut microbiome diversity, abundances, functional pathways, and ecological interactions. Faecalibacterium prausnitzii and Eubacterium rectale, which are both recognized as abundant, health-promoting butyrate producers in the human gut, were found to be reduced in the ME/CFS subjects. As such, microbial capacity for butyrate synthesis was found to be deficient and F. prausnitzii abundance was found to be inversely associated with fatigue severity in these subjects.
- ME/CFS patients have distinct gut microbiome dysbiosis with reduced abundance of F. prausnitzii and E. rectale.
- Butyrate deficiency may be linked to the reduced abundance of F. prausnitzii and E. rectale.
- The more severe fatigue symptoms in ME/CFS may be correlated with the low abundance of F. prausnitzii.
Access the study: https://pubmed.ncbi.nlm.nih.gov/36758522/
Reference: Guo, C., Che, X., Briese, T., Ranjan, A., Allicock, O., Yates, R. A., Cheng, A., March, D., Hornig, M., Komaroff, A. L., Levine, S., Bateman, L., Vernon, S. D., Klimas, N. G., Montoya, J. G., Peterson, D. L., Lipkin, W. I., & Williams, B. L. (2023). Deficient butyrate-producing capacity in the gut microbiome is associated with bacterial network disturbances and fatigue symptoms in ME/CFS. Cell host & microbe, 31(2), 288–304.e8. https://doi.org/10.1016/j.chom.2023.01.004
Effects of probiotics, prebiotics, and synbiotics on polycystic ovary syndrome: a systematic review and meta-analysis
Polycystic ovary syndrome (PCOS) has an unclear pathophysiology; however, genetic, neuroendocrine, and metabolic causes have been proposed. This review summarizes the effects of probiotics, prebiotics, and synbiotics on metabolic parameters, including insulin resistance (IR), lipid profiles, anthropometric indices, and CRP level in PCOS. Eight databases were used to retrieve relevant RCTs published before October 2020. Seventeen studies were included with a total of 1049 participants. The results showed that probiotic, prebiotic, and synbiotic intake decreased fasting plasma glucose, fasting insulin, homeostatic model of assessment for IR, triglycerides, total cholesterol, low-density lipoprotein (LDL) cholesterol, and very-low-density lipoprotein (VLDL) cholesterol, and increased quantitative insulin sensitivity check index. Subgroup analysis based on the type of intervention (probiotics, prebiotics, or synbiotics), study duration (≥ 12 weeks or < 12 weeks), number of probiotic strains (multi or single strain), and probiotic dose (≥ 2×108 colony-forming units [CFU] or < 2×108 CFU) showed that probiotics or prebiotics might be the preferred alternative for ameliorating IR or lipid profiles, respectively, and the effect is positively related to the course and therapeutic dose.
- PCOS has an unclear pathophysiology, but several causes have been suggested including genetic, neuroendocrine, and metabolic.
- The beneficial effects of probiotics, prebiotics, and synbiotics in PCOS are attributed to their activity in modifying IR and lipid profiles.
- IR and lipid profiles might be preferentially ameliorated by probiotics and prebiotics, respectively.
Access the study: https://pubmed.ncbi.nlm.nih.gov/34287081/
Reference: Li, Y., Tan, Y., Xia, G., & Shuai, J. (2023). Effects of probiotics, prebiotics, and synbiotics on polycystic ovary syndrome: a systematic review and meta-analysis. Critical reviews in food science and nutrition, 63(4), 522–538. https://doi.org/10.1080/10408398.2021.1951155