Extracts of black and brown rice powders improve hepatic lipid accumulation via the activation of PPARα in obese and diabetic model mice

<p>Rice powder extract (RPE) from black and brown rice (<i>Oryza sativa</i> L. <i>indica</i>) improves hepatic lipid accumulation in obese and diabetic model mice via peroxisomal fatty acid oxidation. RPE showed PPARα agonistic activity which did not differ between black and brown RPE despite a higher anthocyanin content in black RPE.</p

Phenotypic comparison of C57BL/6J mice fed the chow, AHF, AHF + EPA, and AHF + DHA diet for 4 weeks.

<p>Phenotypic comparison of C57BL/6J mice fed the chow, AHF, AHF + EPA, and AHF + DHA diet for 4 weeks.</p

Effect of EPA and DHA on hepatic lipid content in mice fed AHF diet.

<p>Liver macroscopic picture (A) and hepatic triglyceride (TG) and total cholesterol (T-Cho) levels (B) in mice fed a normal chow, an AHF diet, or an AHF diet supplemented with EPA or DHA for four weeks. n = 12–15 per group. ** p < 0.01, *** p < 0.001 versus chow group; ## p < 0.01, ### p < 0.001 versus AHF group.</p

Effect of AHF diet supplemented with EPA or DHA on hepatic oxidative stress.

<p>Representative immunohistochemical staining for Nε-(Hexanoyl) Lysine in liver section form mice fed a normal chow, an AHF diet, or an AHF diet supplemented with EPA or DHA for four weeks (A). Liver 8-OHdG levels in mice fed a normal chow, an AHF diet, or an AHF diet supplemented with EPA or DHA for four weeks (B). Quantitative real-time PCR of genes involved in oxidative stress in the livers of mice fed a normal chow, an AHF diet, or an AHF diet supplemented with EPA or DHA for four weeks (B). n = 13–15 per group. * p < 0.05 versus chow group; # p < 0.05 versus AHF group.</p

Effect of AHF diet supplemented with EPA or DHA on hepatic fibrogenesis.

<p>Quantitative real-time PCR of genes involved in fibrogenesis in the livers of mice fed a normal chow, an AHF diet, or an AHF diet supplemented with EPA or DHA for four weeks (A). Immunoblot analysis of α-SMA levels and the ratio between α-SMA and β-actin by densitometry analysis (B). n = 13–15 per group. * p < 0.05 versus chow group; # p < 0.05 versus AHF group.</p

Hepatic fatty acid composition in mice fed normal chow, AHF, AHF + EPA and AHF + DHA diets for four weeks.

<p>Hepatic fatty acid composition (A) and the n-6/n-3 fatty acid ratio (B) in livers of mice fed a normal chow, an AHF diet, or an AHF diet supplemented with EPA or DHA for four weeks. n = 3–4 per group. * p < 0.05, *** p < 0.001 versus chow group; # p < 0.05, ### p < 0.001 versus AHF group.</p

Effect of AHF diet supplemented with EPA or DHA on hepatic lipid metabolism-related mRNA and protein levels.

<p>For gene expression and immunoblot analyses, livers were collected from the mice fed a normal chow, an AHF diet, or an AHF diet supplemented with EPA or DHA for four weeks. Quantitative real-time PCR of genes involved in fatty acid and TG synthesis (A), fatty acid oxidation (C), PUFA synthesis (D), lipid storage (E), cholesterol and lipoprotein metabolism (F). Immunoblot analysis for mature SREBP-1 levels (B). n = 13–15 per group. * p < 0.05 versus chow group; # p < 0.05 versus AHF group.</p

Effect of AHF diet supplemented with EPA or DHA on hepaticinflammation.

<p>Representative immunohistochemical staining for F4/80 in liver section form mice fed a normal chow, an AHF diet, or an AHF diet supplemented with EPA or DHA for four weeks (A). Quantitative real-time PCR of genes involved in inflammation in the livers of mice fed a normal chow, an AHF diet, or an AHF diet supplemented with EPA or DHA for four weeks (B). Immunoblot analysis of phosphorylated JNK and total JNK levels and the ratio between phosphorylated and total JNK by densitometry analysis (C). n = 13–15 per group. * p < 0.05 versus chow group; # p < 0.05 versus AHF group.</p

Attenuated hepatic inflammation and liver injury in mice fed AHF supplemented with EPA or DHA.

<p>Hematoxylin and eosin (H&E) staining of liver sections from representative mice from each treatment group (A), and plasma alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels (B). n = 11–15 per group. ** p < 0.01, *** p < 0.001 versus chow group; # p < 0.05, ### p < 0.001 versus AHF group.</p