Ascorbic acid inhibits visceral obesity and nonalcoholic fatty liver disease by activating peroxisome proliferator-activated receptor α in high-fat-diet-fed C57BL/6J mice.
Int J Obes (Lond) 2018;
43:1620-1630. [PMID:
30283077 DOI:
10.1038/s41366-018-0212-0]
[Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Revised: 07/04/2018] [Accepted: 08/29/2018] [Indexed: 02/07/2023]
Abstract
BACKGROUND/OBJECTIVES
Ascorbic acid is a known cofactor in the biosynthesis of carnitine, a molecule that has an obligatory role in fatty acid oxidation. Our previous studies have demonstrated that obesity is regulated effectively through peroxisome proliferator-activated receptor α (PPARα)-mediated fatty acid β-oxidation. Thus, this study aimed to determine whether ascorbic acid can inhibit obesity and nonalcoholic fatty liver disease (NAFLD) in part through the actions of PPARα.
DESIGN
After C57BL/6J mice received a low-fat diet (LFD, 10% kcal fat), a high-fat diet (HFD, 45% kcal fat), or the same HFD supplemented with ascorbic acid (1% w/w) (HFD-AA) for 15 weeks, variables and determinants of visceral obesity and NAFLD were examined using metabolic measurements, histology, and gene expression.
RESULTS
Compared to HFD-fed obese mice, administration of HFD-AA to obese mice reduced body weight gain, visceral adipose tissue mass, and visceral adipocyte size without affecting food consumption profiles. Concomitantly, circulating ascorbic acid concentrations were significantly higher in HFD-AA mice than in HFD mice. Ascorbic acid supplementation increased the mRNA levels of PPARα and its target enzymes involved in fatty acid β-oxidation in visceral adipose tissues. Consistent with the effects of ascorbic acid on visceral obesity, ascorbic acid not only inhibited hepatic steatosis but also increased the mRNA levels of PPARα-dependent fatty acid β-oxidation genes in livers. Similarly, hepatic inflammation, fibrosis, and apoptosis were also decreased during ascorbic acid-induced inhibition of visceral obesity. In addition, serum levels of alanine aminotransferase, aspartate aminotransferase, total cholesterol, and LDL cholesterol were lower in HFD-AA-fed mice than in those of HFD-fed mice.
CONCLUSIONS
These results suggest that ascorbic acid seems to suppress HFD-induced visceral obesity and NAFLD in part through the activation of PPARα.
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