Table 2 The beneficial effects of functional ingredients on LRP6a in vivo and in vitro

Functional ingredients	Species	Concentration	Effects	Reference
6-gingerol	3T3-L1	15 μg/mL	Wnt/β-catenin pathway↑	Li & Zhou., 2015
			mRNA level of LRP6, Dvl2↑, PPARγ, C/EBPα↓
			Protein level of LRP6, Dvl2↑, PPARγ, C/EBPα, FAS, ACC↓
Baicalin	3T3-L1	200 μM	Wnt/β-catenin pathway↑	Lee et al., 2010
			mRNA level of LRP6, Dvl2/3↑, PPARγ, C/EBPα, FABP4, LPL↓
			Protein level of PPARγ, C/EBPα, FABP4, LPL↓
Black rice extracts	C3H10T1/2	40 μg/mL	mRNA level of LRP6, Fzd↑, PPARγ, C/EBPδ, C/EBPα, FAS↓	Kim et al., 2016
Coumestrol	3T3-L1	40 μM	Lipid accumulation↓, Wnt/β-catenin pathway↑	Jang et al., 2016
			Protein level of LRP6↑, PPARγ, C/EBPα, FAS, AP2↓
Delphinidin	3T3-L1	100 μM	Lipid droplet accumulation↓	Rahman et al., 2016
			mRNA level of Wnt1/10b, Fzd2, LRP6-, PPARγ, C/EBPα/β↓
Fucosylated chondroitin sulfate	3T3-L1	200 μg/mL	Lipid droplet accumulation↓, Wnt/β-catenin pathway↑	Xu et al., 2015
			mRNA level of LRP6, Fzd↑
			Protein level of PPARγ, CEBPα, SREBP1, FAS↓
Isorhamnetin	3T3-L1	50 μM	Intracellular cholesterol↓	Lee et al., 2010
			mRNA level of LRP6, Fzd1/4/6/7, PPARγ, CEBPα↓
Kirenol	3T3-L1	40 μM	Lipid accumulation↓	Kim et al., 2014
			mRNA level of LRP6, Dvl2, β-catenin, Cyclin d1↑ , PPARγ,
			CEBPα, SREBP1, FAS, ACC↓
Platycodin D	3T3-L1	10 μM	Lipid accumulation↓, Wnt/β-catenin pathway↑	Lee et al., 2011
			mRNA level of Lrp6↔, Dvl2↑
			Protein level of Dvl2↑, AXIN, PPARγ, C/EBPα, FABP4↓

LRP6, low density lipoprotein receptor-related protein 6; Dvl2/3, segment polarity protein dishevelled homolog 2/3; PPARγ, peroxisome proliferatoractivated receptor γ; C/EBPα/β, CCAAT/enhancer-binding protein α/β; FAS, fatty acid synthase; ACC, acetyl-CoA carboxylase; FABP4, fatty acid binding protein 4; LPL, lipoprotein lipase; AP2, adipocyte protein 2; Fzd 2, frizzled 2; SREBP1/2, sterol responsive element binding protein 1/2