Gut microbiota and metabolic syndrome

Table 1 Studies conducted on animal models showing effects of probiotics containing Bifidobacterium strains on metabolic disorders

Studied animals	Probiotic	Dose	Duration of treatment (wk)	Effects	Ref.
C57BL/6J mice	Bifidobacterium breve B-3	109 CFU	8	↓body weight, epididymal fat, serum cholesterol, glucose, insulin and HOMA index	[99]
				↑expression of FIAF, adiponectin
C57BL-6 mice	Bifidobacterium pseudocatenulatum CECT 7765		7	↓serum cholesterol, triglycerides, glucose, insulin resistance, leptin, IL-6, monocyte chemotactic protein-1, liver steatosis, adipose tissue	[100]
				↑glucose tolerance
				Improvement of immune system functionality
HFD-fed rats	Bifidobacterium longum			Improvement of HFD induced metabolic disorders trough ↓endotoxin levels and intestinal inflammation, ↑expression of Reg I genes	[101]
HFD-rats, standard diets fed rats	Bifidobacterium adolescentis		12	↓visceral fat, liver steatosis	[102]
				↑insulin sensitivity
Sprague-Dawley rats	B. pseudocatenulatum SPM 1204, B. longum SPM 1205, and B. longum SPM 1207	108-109 CFU	7	↓body and fat weights, serum cholesterol, triglycerides, glucose, leptin, AST, ALT and lipase levels	[103]
Sprague-Dawley rats	Bifidobacteria L66-5, L75-4, M13-4 and FS31-12, originated from normal human intestines	108 CFU	6	B. M13-4 strain ↑body weight	[104]
				B. L66-5 strain ↓body weight
				All strains ↓serum and liver triglycerides, serum and liver cholesterol

CFU: Colony-forming units; IL-6: Interleukin-6; HFD: High-fat diet; Reg I genes: Intestinal regenerating family genes; AST: Aspartate aminotransferase; ALT: Alanine aminotransferase; FIAF: Fasting-induced adipose factor; HFD: High-fat diet.

Table 2 Studies conducted on animal models showing effects of probiotics containing Lactobacillus strains on metabolic disorders

Studied subjects	Probiotic	Duration of treatment	Effects	Ref.
C57BL/6J mice	Lactobacillus rhamnosus PL60	8 wk	↓body weight gain, white adipose tissue, hepatic steatosis	[106]
C57BL/6J mice	Lactobacillus plantarum PL62	8 wk	↓body weight, visceral adipose tissue, serum glucose levels	[107]
Sprague-Dawley rats	Lactobacillus gasseri SBT2055	4 wk	↓adipocyte size, leptin levels	[108]
			No significant changes in serum glucose and lipids levels, and liver lipids levels
Zucker diabetic fatty rats	Lactobacillus fermentum NCIMB 5221	8 wk	↓fasting insulin levels, insulin resistance, serum triglycerides and LDL cholesterol levels, atherosclerosis	[109]
			↑HDL cholesterol levels
Male Kunming mice	L. plantarum CAI6, L. plantarum SC4	28 d	↓serum total and LDL cholesterol levels, LDL/HDL cholesterol ratio, triglycerides levels, hepatic steatosis	[110]
			↑serum HDL cholesterol, hepatic anti-oxidant Nrf-2 mediated response
C57BL/6J mice	Lactobacillus rhamnosus GG	13 wk	↓liver and mesenteric adipose tissue, weight gain	[111]
			↑glucose tolerance, gluconeogenesis, fatty acids oxidation
Apoe-/- mice	Lactobacillus reuteri ATCC PTA 4659 (ATCC), DSM 17938 (DSM), L6798	12 wk	↓body weight gain, insulin levels, hepatic steatosis	[112]
			↑fatty acids oxidation
C57BL/6 mice	Lactobacillus plantarum strain No. 14	11 wk	↓adipocyte size, white adipose tissue, serum leptin and total cholesterol levels	[113]
C57B/6J mice	Lactobacillus paracasei ssp paracasei F19	10 d	↓body weight	[114]
			↑triglyceride load of the lipoprotein VLDL, angiopoietin-like 4 protein that ↓fatty storage
GF and NMF mice	Lactobacillus paracasei ssp paracasei F19 or Lactobacillus acidophilus NCFB 1748	10 d	↑adipsin, adiponectin, fatty acids oxidation	[115]
			Improvement of efficacy of intestinal immunological barrier
			↓resistine like β

LDL: Low-density lipoprotein; HDL: High-density lipoprotein; VLDL: Very low-density lipoprotein.

Table 3 Studies conducted on humans showing effects of probiotics on metabolic disorders

Studied subjects	Probiotics	Duration of treatment	Effects	Ref.
Overweight humans	Lactobacillus gasseri SBT2055	12 wk	↓body weight, visceral and subcutaneous fat area, BMI, waist and hip circumference	[116]
			↑serum adiponectin
Subjects with increased abdominal adiposity	Lactobacillus gasseri SBT2055	12 wk	↓body weight, visceral fat area, BMI, waist and hip circumference, body fat mass	[117]
Women affected by postmenopausal metabolic syndrome	Lactobacillus plantarum	90 d	↓serum glucose and homocysteine levels	[118]

BMI: Body mass index.

Table 4 Studies conducted on animal models showing effects of prebiotics on metabolic disorders

Studied subjects	Prebiotic	Duration of treatment	Effects	Ref.
Wistar rats	OFS	50 d	↓Body weight, food intake, fat mass, serum triglycerides, ghrelin	[126]
			↑GLP-1
Wistar rats	OFS	6 wk	↓Food intake, serum glucose and insulin	[127]
			↑GLP-1, glucose tolerance
HFD fed mice	OFS	13 wk	↑Bifidobacterium, glucose tolerance	[105]
			↓Pro-inflammatory cytokines, endotoxemia
C57B/6J mice	OFS	4 wk	↓LPS, hepatic inflammatory and oxidative stress markers, intestinal permeability	[128]
			↑GLP-2
C57B/6J mice	OFS	8 wk	↓Firmicutes/Bacteroides ratio, fat mass, oxidative stress, low grade inflammation	[129]
			↑Glucose tolerance, GLP-1 and leptin sensitivity
C57B/6J mice	AX	4 wk	↑Bacteroides, Prevotella, Roseburia, Bifidobacterium spp	[130]
			Improvement of gut barrier function
			↓Adipocyte size, fatty acids storage, body weight, serum cholesterol, insulin resistance, low grade inflammation	[131]
Lean and obese JCR:LA.cp rats	Inulin-OFS	10 wk	↓Firmicutes, food intake
			↑Bacteroides, Bifidobacterium, satiety hormones

OFS: Oligofructose; GLP-1: GLucagon-like peptide-1; LPS: Lipopolysaccharides; GLP-2: Glucagon-like peptide-2; AX: Arabinoxylose; HFD: High-fat diet.

Table 5 Studies conducted on humans showing effects of prebiotics on metabolic disorders

Studied subject	Prebiotic	Duration of treatment	Effects	Ref.
Healthy men and women	OFS	2 wk	↓Food and energy intake, hunger	[132]
			↑satiety
Healthy humans	GOS	12 wk	Significant ↑Bifidobacterium	[133]
Obese women	Inulin-type fructans	3 mo	↑Bifidobacterium and Faecalibacterium prausnitzii	[134]
			↓Circulating LPS, Bacteroides, Propionibacterium
Obese-dyslipidemic women	Yacon syrup (containing OFS)	120 d	↓Body weight, BMI, waist circumference, serum LDL cholesterol levels	[135]
Overweight and obese adults	OFS	12 wk	↓Body weight, ghrelin, calories intake, serum glucose, insulin	[136]
			↑peptide YY

OFS: Oligofructose; GOS; Galactooligosaccharides; LPS: Lipopolysaccharides; BMI: Body mass index; LDL: Low-density lipoprotein.