Effects of resveratrol and other polyphenols in hepatic steatosis

Table 1 In vitro studies performed with polyphenols

Ref.	Animal model	Polyphenol dose and treatment period length	Effects	Mechanisms
Gnoni et al[27], 2009	HepG2 cells	25 μmol/L resveratrol	↓ Triacylglycerols	↓ ACC activity = FAS activity
		30 min
Zang et al[29], 2006	HepG2 cells	10 μmol/L resveratrol	Prevent lipid accumulation	↑ phosphorylation AMPK (activation) in liver
		24 h		↑ phosphorylation ACC (inhibition) in liver
Shang et al[30], 2008	HepG2 cells	50 μmol/L resveratrol	↓ Triacylglycerols	↑ phosphorylation AMPK liver (activation)
		24 h		↓ mRNA de SREBP1c and FAS liver
Wang et al[28], 2009	Human HepG2 cells	40 μmol/L resveratrol	↓ Triacylglycerols	↓ SREBP 1c
		24 h		↑ SIRT 1
Vidyashankar et al[53], 2013	Hep G2 cells	10 μmol/L quercetin	↓ Triacylglycerols
		24 h	↓ Insuline resistance
			↓ Oxidative stress
			↑ Superoxide dismutase, catalase and glutathione peroxidase activities
Guo et al[60], 2011	Hep G2 cells	Anthocyanin Cy-3-g	↓ Triacylglycerols	Inhibit translocation of GPAT1
		1, 10, 100 μmol/L		↓ GPAT, mtGPAT1 activity
		24 h
Baselga-Escudero et al[61], 2012	FAO cells	Proanthocyanidins	↓ MiR-122 at 25,50,	25 mg/L, ↓ FAS (5 h) protein expression
		10, 25, 50, 100 mg/L	100 mg/L
		1 h	↓ MiR.122, FAS with time (1, 3 h. 25 mg/L)
Pil Hwang et al[62], 2013	Hep G2 cells	3-caffeoyl, 4-dihydrocaffeoylquinic acid	↓ Fat accumulation in a dose-dependent manner	↓ SREBP1c, FAS mRNA and protein expression = LXRα mRNA expression
		1, 3, 10 μmol/L
		1 h		↑ Activating AMPK
				↑ SIRT1
Liu et al[65], 2011	HepG2 cells	Blueberry extract	↓ Triacylglycerols accumulation
		20, 40, 60, 80 and 100 μg/mL 24 h	80 μg/m L ↓ 60% of triacylglycerols accumulation
Lee et al[67], 2012	BALB/c normal liver cells	Extract of Hibicus sabdariffa L	↑ Cell viability	↓ p-JNK and AIF, tBid and Bax protein expression
	Steatosis produced by	0.05, 0.1, 0.5, 1 mg/mL		↓ Lipid peroxidation
	acetaminophen	48 h		↑ Catalase and GSH
Wang et al[66], 2012	HepG2	Extract of Ginkgo biloba	↓ Triacylglycerols	↑ CPT-1a, ACO mRNA expression
		200 μg/mL in vitro		↓ FAS, Acac-β mRNA expression
		24 h		↑ CPT-1a protein expression

↓: Decrease; ↑: Increase. RSV: Resveratrol; ACC: Acetyl CoA carboxylase; FAS: Fatty acid synthase; AMPK: AMP-activated kinase; SREBP1c: Sterol regulatory element binding protein 1c; SIRT1: Sirtuin 1; Q: Quercetin; GPAT1: Glycerol-sn-3-phosphate acyltransferase 1; mtGPAT1: Mitochondrial glycerol-sn-3-phosphate acyltransferase 1; LXRα: Liver X receptor α; pJNK: Activated c-Jun N-terminal kinase; AIF: Apoptosis inducing factor; GSH: Glutathione; CPT-1a: Carnitine palmitoyltransferase 1a; ACO: Acyl-coenzyme A oxidase 1; Acacβ: Acetyl-coenzyme A carboxylase β.