Effects of resveratrol and other polyphenols in hepatic steatosis

Table 5 In vivo studies carried out with polyphenol extracts

Ref.	Animal model	Polyphenols extract, dose and treatment period length	Effects	Mechanisms
Feillet-Coudray et al[72], 2009	Male Wistar rats fed a high-fat diet	Provinol®, a polyphenol extract obtained from red wine	↓ Macroesteatosis
		0.2% in the diet	↓ Lipid droplets
		6 wk	↓ Lipid peroxidation
Aoun et al[73], 2010	Male Wistar rats fed a high fat diet	Provinol®, a polyphenol extract obtained from red wine	↓ Triacylglycerols	↑ SIRT protein expression
		0.2% in the diet	↓ Macroesteatosis
		6 wk	= Fatty acid composition	= SCD1, pAMPK, SREBP-1c, FAS, HNF-4 α, PGC1α and CPT-1a protein expression
Beltrán-Debón et al[68], 2011	LDLr-/- mice fed a standard diet	Aspalathus linearis L. (rooibos)	Lower steatosis degree	↑ AMPK protein expression
		10 g/L drinking water
		14 wk
Tsuruta et al[69], 2011	db/db mice fed a standard diet	Nelumbo nucifera L. (lotus root)	↓ 15% Liver weight (tendency)	= CPT-1a activity
		0.5% in the diet	↓ 62%Triacylglycerols (tendency)	↓ FAS, ME activity
		3 wk	↓ Transaminases (tendency)
Axling et al[70], 2012	C57BL/6 J mice fed a high fat diet	Green tea	↓ Liver weight	↓ SREBP-1c, PPAR-γ, ACC mRNA (22 wk)
		4% in the diet	↓ Triacylglycerols
		11 and 22 wk	↓ Serum ALT
Lee et al[67], 2012	BABL/c mice fed a standard diet Steatosis produced by acetaminophen	Extract of Hibicus sabdariffa L 0.01%, 0.02% or 0.03% in the diet 2 wk	↓ Liver damage ↓ Liver steatosis ↓ Serum ALT, AST (dose dependent) ↓ Oxidative stress	↓ p-JNK and AIF, tBid and Bax protein expression
Wang et al[66], 2012	Male Wistar rats fed a high-fat diet	Extract of Ginkgo biloba	↓ Triacylglycerols	↑ CPT-1a activity
		0.25% in the diet		↑ CPT-1a, Acaa1, Slc25a20, Hadh, ACO, PPAR-α, RXR-α mRNA expression,
		12 wk		↓ FAS mRNA expression
Park et al[71], 2013	C57BL/6 J mice fed a high-fat diet	Extract of grape skin	↓ Triacylglycerols	↓ FAS, SCD1, PAP
		0.15% in the diet	↓ Serum leptin	↑CPT-1a, PPAR-α mRNA expressions and activities
		(160 mg/kg bw per day)	↑ Serum adiponectin	↓ PPAR-γ,
		10 wk		↑ PPAR-α, CPT-1a mRNA expressions
				↑β oxidation,
				= CPT-1a activity
Yui et al[74], 2013	OLETF rats fed a standard diet	Humulus lupulus L. (hop pomace)	↓Liver weight (tendency)	↓de novo lipogenesis
		1% in the diet	↓ Triacylglycerols (tendency)	= ACO, CPT-1a activity
		70 d

↓: Decrease; ↑: Increase. SIRT: Sirtuin 1; SCD1: Stearoyl-CoA desaturase; AMPK: AMP-activated kinase; pAMPK: Phosphorylated AMP-activated kinase; SREBP-1c: Sterol regulatory element binding protein 1c; FAS: Fatty acid synthase; HNF-4α: Hepatocyte nuclear factor 4 α; PGC-1α: Peroxisome proliferator-activated receptor-c coactivator 1α; CPT-1a: Carnitine palmitoyltransferase 1a; ME: Malic enzyme; ALT: Alanine aminotransferase; PPAR-γ: Peroxisome proliferator activated receptor γ; ACC: Acetyl CoA carboxylase; pACC: Phosphorylated acetyl CoA carboxylase; AST: Aspartate aminotransferase; p-JNK: Activated c-Jun N-terminal kinase; AIF: Apoptosis inducing factor; Acaa1: acetyl-coenzyme A acyltransferase 1; Slc25a20: Solute carrier family 25, member 20; Hadh: Hydroxyacyl-coenzyme A dehydrogenase; ACO: Acyl-coenzyme A oxidase; PPAR-α: Peroxisome proliferator activated receptor α; RXR-α: Retinoid X receptor α; PAP: Phosphatidate phosphohydrolase.