Table 2.

Summary of the in vivo studies included in the present review.

Legume Source	Reference	Study Design	Parameters Measured	Key Findings
Soybean (Glycine max. L.)	Zhang et al. [1]	⋅Male Sprague Dawley rats (150–180 g) ⋅Groups: (1) Basal control (normal diet); (2) HFD insulin-resistant (IR control; sterilized water as vehicle control); (3) HFD + low-dose ISO (50 mg/kg/day intragastric administration (i.g.)); (4) HFD + medium-dose ISO (150 mg/kg/day i.g.); (5) HFD + high-dose ISO (450 mg/kg/day i.g.) ⋅30-day study	⋅Insulin resistance index (HOMA-IR) ⋅Fasting insulin (RIA kit) ⋅Fasting plasma glucose (commercial reagent paper) ⋅Fasting plasma adiponectin, leptin, resistin (rat ELISA kits) ⋅Tissue weights (epididymal and peri-renal fat pads) ⋅mRNA levels in peri-renal adipose tissue (quantitative real-time PCR (RT-PCR); 45 cycles)	⋅ISO ↓ fat pad weights, no differences in body weights among groups ⋅ISO ↓ fasting insulin and HOMA-IR vs. IR control ⋅ISO (150 and 450 mg/kg/day) ↑ plasma and mRNA adiponectin and leptin levels, ↓ plasma resistin levels ⋅ISO (450 mg/kg/day) ↓ mRNA resistin levels ⋅Positive correlation between plasma resistin and HOMA-IR ⋅Negative correlation between plasma adiponectin and HOMA-IR
	Nizamutdinova et al. [38]	⋅Male Sprague Dawley rats (220–250 g) ⋅Streptozotocin (STZ; 50 mg/kg) injected intraperitoneally to induce diabetes ⋅Anthocyanins extracted from black soybeans ⋅Groups: (1) Control (no STZ); (2) Diabetes control (STZ); (3) Anthocyanin (50 mg/kg) pre-diabetes (ANT-PRE) + STZ; (4) STZ + Anthocyanin (50 mg/kg) post-diabetes (ANT-POST) ⋅30-day study	⋅Protein levels (Western blotting) ⋅Fasting serum insulin (ELISA kit) ⋅Fasting blood glucose (glucometer)	⋅Anthocyanins ↓ blood glucose levels of diabetic rats vs. diabetic control group ⋅Anthocyanins ↑ fasting serum insulin of diabetic rats vs. diabetic control group ⋅Anthocyanins ↑ GLUT4 levels in skeletal muscle vs. diabetic control group
	Ali et al. [64]	⋅Male lean and obese Spontaneously hypertensive rat/N-corpulent (SHR/N-cp) rats (7–8 weeks old) ⋅Basal diet: American Institute of Nutrition 93G formula ⋅Soy isoflavone (ISO) supplementation (0.1% w/w) ⋅20-week study	⋅Tissue weights (peri-renal, ileal, subdiaphragmatic, epididymal fat pads)	⋅Soy ISO ↓ body weight of obese rats ⋅Soy ISO ↓ peri-renal, epididymal, and subdiaphragmatic fat pad weights in lean and obese rats ⋅Soy ISO ↓ ileal fat pads in obese rats
	Zanella et al. [70]	⋅Male C57BL6/J mice (3-weeks old) ⋅Basal diet: low-fat diet (LFD) ⋅Study 1 groups: (1) LFD (soy-free); (2) LFD + Soybean supplementation (8.5% w/w) ⋅Study 2 groups: (1) LFD + vehicle (sham control); (2) LFD + genistein (5 mg/kg/day by oral gavage) ⋅Study 1: 147 days; Study 2: 15 days	⋅Glucose tolerance test (glucometer) ⋅Insulin resistance test (0.75 Units insulin injected intraperitoneally; tail vein blood samples) ⋅Body composition (Echo magnetic resonance imaging) ⋅Tissue weights (epididymal and peri-renal fat pads)	⋅Soy treatment ↑ total fat mass and ↑ fat pad mass vs. soy-free control group ⋅Genistein ↑ adipose tissue mass vs. sham control ⋅No differences in lean mass or total body weight between groups in Study 1 or Study 2 ⋅No difference in glucose metabolism or insulin sensitivity between groups in Study 1 or Study 2
	Kavanagh et al. [80]	⋅Mature insulin-resistant female monkeys (cynomolgus macaques and African green monkeys) ⋅Soy isoflavone (ISO) supplementation (155 mg/day) ⋅4-month study	⋅Glucose tolerance test (femoral intravenous collection: 5, 10, 20, 30, 60 min) ⋅Insulin resistance test (hyperinsulinemic-euglycemic clamp) ⋅Fasting plasma glucose (colorimetric assay) ⋅Fasting insulin (ELISA kit) ⋅Fasting plasma adiponectin (ELISA kit)	⋅ISO ↑ insulin area under the curve vs. control ⋅No effect of ISO on glucose area under the curve ⋅No effect of ISO on circulating adiponectin levels
	Zhou et al. [86]	⋅Huangjiang mini-piglets (weaned at 21 days of age) ⋅Groups: (1) Basal diet + 0.5% w/w corn starch (control); (2) Basal diet + 0.5% w/w soybean galactooligosaccharides (SBOS) ⋅14-day study	⋅Short-chain fatty acid analysis (intestinal luminal samples by gas chromatography) ⋅Gut microbial composition (RT-quantitative PCR)	⋅SBOS ↑ intestinal short-chain fatty acids and number of beneficial bacteria vs. control group ⋅SBOS ↓ numbers of harmful bacteria vs. control group
Chickpea (Cicer arietinum L.)	Dai et al. [41]	⋅Male CD-1 (ICR) IGS mice (6-weeks old) ⋅α-galactooligosaccharides (α-GOS) extracted from chickpeas added to drinking water ⋅Groups: (1) Normal chow; (2) HFD; (3) HFD + low-dose α-GOS (0.083 g/kg/day); (4) HFD + medium-dose α-GOS (0.42 g/kg/day); (5) HFD + high-dose α-GOS (0.83 g/kg/day) ⋅6-week study	⋅Blood glucose (glucometer) ⋅Serum insulin (rat/mouse insulin enzyme-linked immunosorbent assay (ELISA) kit) ⋅Insulin resistance index (HOMA-IR) ⋅Short-chain fatty acid analysis (luminal samples by high-performance liquid chromatography) ⋅Gut microbial composition (quantitative PCR of fresh fecal samples)	⋅HFD ↓ short-chain fatty acids, total bacterial quantity, & altered microbial composition ⋅α-GOS ↑ short-chain fatty acids vs. HFD and normal chow groups ⋅α-GOS stimulated Bifidobacterium and Lactobacillus growth vs. HFD
	Yang et al. [66]	⋅Male Sprague Dawley rats (8 weeks old) ⋅Diets: (1) standard chow; (2) high-fat diet (HFD); (3) HFD + chickpeas (10% raw, crushed chickpea seeds) ⋅8-month study	⋅Insulin tolerance test (insulin at 2 Units/kg, intraperitoneal) ⋅Oral glucose tolerance test (fasting glucometer readings from tail vein) ⋅Fasting serum leptin (rat leptin radioimmunoassay (RIA) kit) ⋅Fasting serum insulin (rat insulin ELISA kit) ⋅Tissue weights (epididymal fat, skeletal muscle, liver) ⋅Triglyceride content (Folch extraction method) ⋅mRNA levels (Northern blot analysis of total RNA)	⋅Chickpeas ↓ HOMA-IR, postprandial glucose, postprandial insulin levels vs. HFD ⋅Chickpeas ↓ epididymal fat pad weight vs. HFD ⋅Chickpeas ↓ hepatic and muscle triglycerides vs. HFD ⋅Chickpeas ↓ leptin mRNA levels vs. HFD in epididymal adipose
N/A	Choi et al. [65]	⋅Female Sprague Dawley rats (5 weeks old) ⋅Ovariectomy (OVX) or sham operation ⋅Groups: (1) Sham + HFD; (2) OVX + HFD; (3) OVX + HFD + genistein (0.1% w/w ; 90% pure) ⋅4-week study	⋅Fasting serum glucose (enzyme assay kit) ⋅Fasting serum insulin, adiponectin, leptin (ELISA kits) ⋅Insulin sensitivity (HOMA-IR) ⋅Tissue weights (liver and adipose) ⋅Adipocyte histology (hematoxylin & eosin stain) ⋅Gene expression (microarray analysis)	⋅Genistein ↓ HOMA-IR vs. OVX group fed HFD ⋅Genistein ↓ triglyceride accumulation and gonadal fat pad ewight ⋅Genistein ↓ hepatic fatty acid synthase activity ⋅Genistein ↓ fat synthesis genes ⋅Genistein ↑ fat degradation genes ⋅No differences in serum adiponectin or leptin between groups
N/A	Weitkunat et al. [84]	⋅Male C57BL/6J mice (8 weeks old) ⋅Diets: (1) LFD; (2) HFD with 10% dietary fibre (HFD control); (3) HFD with 5% SCFA and 5% dietary fibre ⋅30-week study	⋅Oral glucose tolerance test (fasting glucometer readings from tail vein) ⋅Insulin sensitivity (HOMA-IR) ⋅Adipocyte histology (hematoxylin & eosin stain) ⋅mRNA levels (RT-PCR) ⋅Enzyme activity (developed assays)	⋅SCFA ↓ HOMA-IR vs. HFD control group ⋅Negative correlation between propionate and HOMA-IR ⋅SCFA ↓ total adipocyte numbers and promoted small adipocytes vs. HFD control group ⋅SCFA ↑ cytochrome c oxidase activity vs. HFD control group ⋅SCFA ↑ mRNA levels of adipocyte browning markers
N/A	Stahel et al. [91]	⋅Male Sprague Dawley rats (225–250 g) ⋅Groups: (1) Basal diet + 15% methylcellulose (Control); (2) Basal diet + 15% w/w GOS ⋅9-week study	⋅Insulin sensitivity (hyperinsulinemic-euglycemic clamp) ⋅Gut microbial populations (DNA isolated from fecal samples)	⋅GOS ↑ Bifidobacterium spp., Bacteroidetes, Lactobacillus spp. vs. control group ⋅No differences in insulin sensitivity between GOS and control

Abbreviations: ↓, decrease; ↑, increase; ELISA, enzyme-linked immunosorbent assay; α-GOS, α-galactooligosaccharides; HFD, high-fat diet; HOMA-IR, homeostasis model assessment-insulin resistance; i.g., intragastric administration; IR, insulin resistant; ISO, soy isoflavones; mRNA, messenger ribonucleic acid; RIA, radioimmunoassay; RT-PCR, quantitative real-time polymerase chain reaction; SHR/N-cp, Spontaneously hypertensive rat/N-corpulent.