Table 2 Prebiotics (non-digestible carbohydrates)
From: Effects of dietary fibers and prebiotics in adiposity regulation via modulation of gut microbiota
Prebiotic | No. of study population | Study design | Treatment | Duration | Results | Author references |
|---|---|---|---|---|---|---|
Animal studies | ||||||
Barley (Hordeum vulgare), β-glucan | 20, 6-week-old male C57BL/6 mice (n = 9–10/group) | HFD-B diet; corn starch (18.5% w/w) and cellulose (6% w/w) in HFD were replaced with barley fraction | high-fat diet (HFD) or a high-fat diet with barley containing 9.2% β-glucan (HFD-B) | 7 weeks | Total and LDL cholesterol concentrations were significantly reduced in the HFD-B group while fecal cholesterol and bile acid was increased | Hoang et al. [66] |
Fungal chitin-glucan (CG) | 24, 9-week-old male C57bl6/J mice (n = 8/group) | HFD: 35% fat—16% maltodextrin, 26% protein and 6.5% cellulose | HFD with fungal CG (10% w/w) | 4 weeks | Significant increase in bacteria related to Clostridium cluster XIVa, including Rosseburia spp., decrease in fat production and weight gain | Neyrinck et al. [58] |
Hydroxypropyl methylcellulose (HPMC) | 30, 18-week-old male C57BL/6 mice (n = 10/group) | HFD 60% cal | HFD (control), or switched to HFD supplemented with 10% HPMC, or a low-fat diet (LFD) | 8 weeks | Reduced weight gain, plasma cholesterol, liver triglycerides. Increased Bacteroides while decreasing Lactobacillus and Roseburia spp. Yields tenfold higher short-chain fatty acid concentrations | Cox et al. [62] |
Polysaccharide PolyGlycopleX (PGX) | 66, 9–10 week-old Zucker diabetic fatty (ZDF) rats (n = 11/group) | Chow diet; 24% fat (wt/wt) and containing the test fiber, PGX, or cellulose | cellulose as vehicle, 5% polysaccharide PolyGlycopleX (PGX) fiber with 200 mg/kg metformin (MET) or 10 mg/kg sitagliptin (S) | 6 weeks | PGX + MET and PGX + S/MET reduced glycemia, fat mass and hepatic lipidosis. Increased GLP-1 secretion. Bifidobacterium and Clostridium coccoide were reduced in all groups. Bacteroides and Enterobacteriaceae significantly increased | Reimer et al. [70] |
Meju, fermented soy beans (FSF) | 32, 8-week-old male C57BL/6 mice (n = 8/group) | HFD 45% cal | cellulose as control, FSF, meju extract (50 mg/kgBW), oral administration | 12 weeks | Reduced plasma cholesterol, triglyceride, adipocyte size, and hepatic lipid accumulation. Reduced HMG-CoA reductase expression. Increased fatty acid uptake and beta-oxidation. Decrease plasma C-reactive protein, TNF-α, and interlukin-6 levels | Kim et al. [25] |
Yellow pea fiber | 100, 5-week-old males Sprague–Dawley rats | High-fat.high-sucrose diet; (g/100 g): casein (20.0), sucrose (49.9), soybean oil (10.0) | (1) control; (2) oligofructose (OFS); (3) yellow PF; (4) yellow pea flour (PFL); or (5) yellow pea starch (PS) | 6 weeks | Pea flour attenuated weight gain, significantly lower final percent body fat, ower fasting glucose and glucose AUC. Firmicutes/Bacteroidetes ratio was reduced | Eslinger et al. [64] |
Fermented green tea extract (FGT) | 48, 8-week-old male C57BL/6 mice (n = 16/group) | Normal diet [ND], high-fat diet [HFD], and HFD-FGT [FGT] | FGT (500 mg/kg; dissolved in 0.1% methylcellulose or (0.1% methylcellulose as vehicle, oral administration | 8 weeks | FGT reduced body weight gain and fat mass. Lipogenic and inflammatory genes were downregulated. Alleviated glucose intolerance and fatty liver symptoms. Restored the Firmicutes/Bacteroidetes and Bacteroides/Prevotella ratios) | Seo et al. [27] |
Prebiotic milk oligosaccharides (MO) | 72, 4-week-old male C57BL/6 mice (n = 6/group) | HFD 40% cal | HF (40% fat/kcal), or HF + prebiotic [6%/kg bovine milk oligosaccharides (MO) or inulin] | 6 weeks | Attenuated weight gain, decreased adiposity, and decreased caloric intake. Increased abundance of beneficial microbes Bifidobacterium and Lactobacillus in the ileum | Hamilton et al. [65] |
Human studies | ||||||
Inulin-type fructans | 48 individuals with overweight or obesity | Randomized, double blind, placebo-controlled intervention | 21Â g/day oligofructose or maltodextrin (placebo) | 12Â weeks | Reduced body weight, caloric intake. No difference in fasting glucose, insulin ghrelin, GLP-1, PYY and leptin levels. After MTT: Reduced glycemia, insulin, AUC for ghrelin, PYY and leptin. No difference in AUC for GLP-1 or GIP | Parnell et al. [54] |
Inulin, hydroxypropyl methylcellulose | 49 obese or overweight subjects | Controlled dietary intervention | Energy-restricted high-protein diet with a low glycemic index and soluble fiber diet followed by a weight-maintenance diet | 12Â weeks | Reduction in body-fat mass, adipocyte diameter and improvements in insulin sensitivity and markers of metabolism and inflammation. A progressive reduction occurred in systemic inflammation markers | Cotillard et al. [61] |
Trans-galactooligosaccharides | 45 overweight adults | Double-blind, randomized, placebo (maltodextrin)-controlled, crossover study | Placebo (maltodextrin) or galactooligosaccharides (5.5Â g/day) reconstituted in water. | 12Â weeks | Increased the number of fecal bifidobacteria at the expense of less desirable groups of bacteria. Increases in fecal secretory IgA and decreases in fecal calprotectin, plasma C-reactive protein, insulin, total cholesterol (TC), TG, and the TC:HDL cholesterol ratio | Vulevic et al. [59] |
Oligofructose | 42 boys and girls, ages 7–12 years, overweight | Randomized, double-blind, placebo-controlled trial | 8 g/day oligofructose-enriched inulin/d or placebo (maltodextrin) | 16 weeks | Fasting adiponectin (P = 0.04) and ghrelin (P = 0.03) increased, reduce BMI and food consumption. No differences in fasting concentrations of GLP-1 and PYY | Hume et al. [68] |