Table 4.
Modulation of gut microbiota in humans.
| Reference | Intervention/modulation | Metabolic disorder | Study design | Effects on gut microbiota and metabolic derangements including other alterations |
|---|---|---|---|---|
| Andreasen et al. and Asemi et al. [47,48] | Probiotic (L. acidophilus and B. animalis) | Insulin resistance; Diabetes mellitus | Randomized, double-blind, controlled studies. 45 males with type 2 diabetes, impaired or normal glucose tolerance treated with/without L. acidophilus for 4 weeks and controlled clinical trial; 70 pregnant women given a probiotic yoghurt containing L. acidophilus and B. animalis (200 g/day) for 9 weeks |
↑ L. acidophilus ↑ Insulin sensitivity in probiotic group ↓ insulin resistance |
| Ejtahed et al. [49,50] | Probiotic (L. acidophilus and B. lactis) | Diabetes mellitus | Randomized, double-blind, controlled trials. 60–64 patients with type 2 diabetes mellitus consumed probiotic/non-prebiotic yogurt containing L. acidophilus and B. lactis (300 g/day) for 6 weeks |
Gut microbiota: Uncharacterized ↓ Blood glucose and HbA1c ↓ TC and LDL-C in probiotic group ↓ Atherogenic indices (TC:HDL-C ratio and LDL-C:HDL-C ratio) ↑ Erythrocyte TAS, SOD and GPx activities ↓ Serum MDA |
| Kadooka et al. and Jung et al. [52,53] | Probiotic (L. gasseri) | Overweight and Obesity | Randomized, multicenter, double-blind, placebo-controlled trial. 57 or 87 obese subjects received fermented milk containing L. gasseri or without (200 g/day) for 12 weeks |
↓ Body weight ↓ BMI ↓ Abdominal visceral, subcutaneous and total fat areas in prebiotic group ↓ Waist and hip circumferences ↓ Waist-to-hip ratio |
| Asemi et al. [51] | Probiotic and prebiotic. Probiotic (L. acidophilus, L. casei, L. rhamnosus, L. bulgaricus, B. breve, B. longum, S. thermophilus) Prebiotic (fructo-oligosaccharide) |
Diabetes mellitus | Randomized, double-blind, placebo-controlled clinical trial. 54 diabetic patients ingested a multispecies probiotic/non-prebiotic supplement (consisting of L. acidophilus, L. casei, L. rhamnosus, L. bulgaricus, B. breve, B. longum, S. thermophilus and fructo-oligosaccharide) for 8 weeks |
Gut microbiota: Uncharacterized ↓ Blood glucose increments ↓ Insulin resistance ↓ Serum hs-CRP ↑ Plasma GSH levels |
| Cani et al. and Parnell and Reimer [70,71] | Prebiotic (oligofructose or a mixture of glucosyl- (fructosyl)n-fructose and (fructosyl)mfructose extracted from chicory roots) | Healthy, overweight and obesity | Randomized, double-blind, parallel, placebo-controlled trial 10 healthy adults given 16 g of prebiotics/day | ↑ Marker of gut microbiota fermentation (breath-hydrogen excretion) ↓ Body weight ↓ Caloric intake ↓ Plasma glucose and postprandial glucose responses ↓ Insulin levels ↑ Levels of GLP-1 and peptide YY ↓ Ghrelin levels |
| Sasaki et al. [72] | Prebiotic (transglucosidase) | Healthy and Diabetes mellitus | Randomized, double-blind, parallel, placebo-controlled study. 60 diabetic patients received 300 or 900 mg/day of transglucosidase for 12 weeks. |
↑ Bacteroidetes-to-Firmicutes ratio ↓ Body weight ↓ Blood glucose |
| Jernberg et al. and O’Sullivan et al. [90,91] | Antibiotics (Clindamycin) | Healthy adults | 42 elderly subjects were treated with one antibiotic within 1 month | ↓ Bacteroides ↓ Bifidobacterium spp. Metabolic derangements: Unevaluated |
| Zhang et al. And Kong et al. [25,92] | Gastric bypass | Obesity | Comparison of the structures of microbes in individuals with normal weight, morbid obesity and post-gastric-bypass surgery | ↓ Firmicutes ↑ Proteobacteria ↑ Alterations of WAT genes ↑ Associations between gut microbiota composition and WAT gene expression Metabolic derangements: Unevaluated |
| Kashyap et al. [93–95] | Bariatric surgery | Obesity and Diabetes mellitus | Randomized, prospective, controlled and nonrandomized, controlled observational trials Type 2 diabetic subjects with moderate obesity received bariatric surgery Changes of gut microbial composition 3 months before and after RYGB in morbidly obese patients with type 2 diabetes mellitus |
↑ Proteobacteria ↓ Firmicutes and Bacteroidetes ↑ Weight loss ↓ Blood glucose ↓ HbA1c ↑ Pancreatic β-cell function ↑ Insulin sensitivity ↓ Adiposity ↑ GLP-1 and peptide YY levels ↓ Ghrelin levels |
| Duncan et al. [96,97] | Weight loss/Caloric restriction | Obesity | Obese and non-obese individuals under conditions of weight maintenance, and undergoing weight loss on reduced carbohydrate diets for 4 weeks | ↓ Total fecal SCFAs ↓ Abundance of butyrate-producing bacteria such as Firmicutes, Bifidobacteria, Eubacterium rectale and Roseburia spp. Metabolic derangements: Unevaluated |
| Kim et al. [98] | Weight loss/Caloric restriction/Vegetarian diet | Obesity and Diabetes mellitus | Obese individuals with type 2 diabetes and/or hypertension assigned to a vegetarian diet for 1 month | ↓ Firmicutes-to-Bacteroidetes ratio ↓ Body weight ↓ Fasting and postprandial glucose ↓ HbA1c ↓ TC, LDL-C and TG |
| Santacruz et al. and Nadal et al. [99,100] | Weight loss, caloric restriction or increased physical activity | Obesity | Longitudinal intervention study Overweight and obese individuals placed on a calorie-restricted diet and increased physical activity program for 10 weeks | ↑ Weight loss ↓ BMI and BMI z-score ↑ Total bacteria, Bacteroides-Prevotella group and Lactobacillus group counts ↓ Clostridium coccoides group, Bifidobacterium longum, and Bifidobacterium adolescentis counts Reduced body weight and BMI z-score correlated with reduction of certain gut microbes |
HbA1c, glycated hemoglobin; LDL-C, low-density lipoprotein cholesterol; HDL-C, high-density lipoprotein cholesterol; TG, triglycerides; TC, total cholesterol; SOD, superoxide dismutase; GPx, glutathione peroxidase; MDA, malondialdehyde; TAS, total antioxidant status; GSH, glutathione; BMI, body mass index; hsCRP, high-sensitivity C-reactive protein; SCFAs, short chain fatty acids; WAT, white adipose tissue; ↑ = Increase/enhance; ↓ = Reduce/suppress.