Obesity is arguably one of the biggest healthcare challenges in industrialized countries. The prevalence of obesity has been increasing globally over the past few decades. Currently, there are more than 1 billion overweight or obese adults in the world. As a result, the American Medical Association (AMA) declared obesity a disease in June 2013. Treating the enormous burden of obesity-related diseases on society is urgently needed to manage this public health problem.
The gut microbiome can be thought of as an "organ" that contributes to metabolism and plays a role in energy storage. Evidence to date suggests that manipulating the gut microbiota may be an effective treatment for preventing or managing obesity, so dietary fiber may be an effective strategy for improving and managing obesity by modulating the gut microbiota.
Konjac powder (KF) mainly contains konjac glucomannan (KGM), which is a water-soluble polysaccharide (dietary fiber). Konjac products are listed by the World Health Organization as one of the "Top Ten Health Foods". Important health benefits of KF include lowering cholesterol, normalizing blood triglyceride (TG) concentrations, improving blood sugar levels, immune function, promoting intestinal activity and wound dressings. KF is important for maintaining homeostasis of the intestinal flora and protecting the intestinal barrier, so it is often referred to as a prebiotic. To date, however, there has been little clinical information on the effects of KF on body weight, obesity-related diseases, and the gut microbiome.
The objective of this study was to investigate the clinical efficacy of KF in obese adults. Obesity index, blood parameters and gut microbiome were analyzed.
1. Effect of KF treatment on obesity index and blood parameters
The study included 90 participants. A total of 38 KF subjects and 31 control subjects completed the study, with an overall study retention rate of 76.7%. Prior to the intervention, there were no significant differences in obesity index and blood parameters between the KF group and the placebo group (Table 1). Consumption of KF and placebo did not cause any adverse effects, and body mass index (BMI), fat mass, percentage of body fat (PBF), triglycerides (TG), glycosylated hemoglobin glycosylated hemoglobin (HbA1c), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were significantly reduced among KF consumers (p
2. Effect of KF treatment on intestinal flora diversity and richness
The species and Chao1 indices observed in the AKF group increased significantly (p = 0.0235, p = 0.0044) compared to the BKF group (Figures 2A, B). However, the species observed in ap, the Chao1 index, Simpson index, and Shannon index decreased significantly compared to the BP group (p = 0.0104, p = 0.0102, p = 0.0317, p = 0.0274) (Figure 2A-D). These results suggest that KF treatment significantly increases the diversity α gut microbiome.
The Venn diagram analysis showed that only 449 of the total richness of the 1743 otu were shared across all samples (Figure 2E). The BP group had 674 OTUs, the AP group had 576 OTUs, the BKF group had 946 OTUs, and the AKF group had 1,014 OTUs. To measure the degree of similarity between microbial communities, β diversity was calculated using principal coordinate analysis (Figure 2F). The principal coordinate analysis showed that the KF-treated samples would come together and the pre-treatment samples would move away. These data suggest that KF treatment significantly improves the richness and diversity of the intestinal flora.
3. Effect of KF treatment on the composition of the intestinal microbiota
Before and after KF treatment, the composition of the intestinal flora changes significantly.
At the gate level, the relative abundance of Actinobacteria and Academia in the AKF group increased significantly compared to the BKF group (p
At the section level, the relative abundance of Lachnospiraceae, Bacillaceae, Aerococcaceae, Solirubrobacteraceae, 288-2 and RB41 was significantly increased after KF treatment, while the relative abundance of Sporolactobacacelaceae was significantly reduced after KF treatment (p
At the geniological level, after KF treatment, Roseburia, Lachnoclostridium, erysipelotricaceae UCG-003, Lachnospiraceae NK4A136 group, Lachnospiraceae UCG-004, Fusicatenibacter, Lachnospiraceae UCG-003, senstridium Sensu stricto 13, Howardella, ntestinimonas, Bacillus Bacillus Holdemania, Epulopiscium, Candidatus, Soleaferrea, Solobacterium, Solirubrobacter and Abiotrophia increased significantly, while Lactococcus, Eubacterium brachy group, Sporolactobacillus, Geobacillus and Silanimonas decreased significantly (Figure 3C). In addition, the relative abundance of Dolea in the AP group was significantly reduced compared to the BP group (p
At the species level, compared to the BKF group, Roseburia inulinivorans, Clostridium perfringens, inimonas butyriciproducens, Actinomyces graevenitii, Clostridium sp. The relative abundance of ATCC 29733 and Solobacterium moorei was significantly increased. Compared to the BKF group, the AKF group's garvieae, Lactococcus garvieae, coprophilus, Bacteroides coprophilus, Bacteroides ovatus, caccae Bacteroides, Bacteroidales bacterium ph8, thetaiotaomicronoides Thetaiotaomicron and Geobacillus stearmophilus were significantly reduced (p
All in all, KF treatment can add some beneficial bacteria and reduce some harmful bacteria.
4. Intestinal flora is related to obesity index and blood parameters
At the gate level, 5 gates were significantly associated with obesity index and blood parameters (p
At the section level, 13 families were significantly associated with obesity index and blood parameters (p
At the genus level, 16 genera were significantly associated with obesity index and blood parameters (p
At the species level, 15 species were significantly associated with obesity index and blood parameters (p
Taken together, these bacteria affect obesity index and blood parameters.
Overall, KF interventions can reduce obesity indicators and blood parameters, regulate the diversity and composition of the intestinal flora, promote the growth of beneficial bacteria, and inhibit the growth of harmful bacteria. In addition, changes in the microbiota have a strong correlation with obesity index and blood parameters. These findings support the anti-obesity and other effects of KF may be mediated by its selective regulation of the microbiota.
Original source:
Li Y, et al. Effects of Konjaku Flour on the Gut Microbiota of Obese Patients. Front Cell Infect Microbiol. 2022 Mar 1;12:771748. doi: 10.3389/fcimb.2022.771748. PMID: 35300378; PMCID: PMC8921482.
Source | A new frontier in endocrinology
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