Impaired
lipid and
glucose metabolism in the liver is a crucial characteristic of
nonalcoholic fatty liver disease (
NAFLD).
Coniferaldehyde (CA), a kind of phenolic compound found in many edible plants, has multiple
biological and pharmacological functions. However, since the effect and molecular mechanism of CA on hepatic
lipid and
glucose metabolism disorders in
NAFLD remain unknown, this study investigated its impact on the
lipid and
glucose metabolism of
palmitic acid (PA)-induced HepG2 cells. Compared with the HepG2 cells treated only with PA, supplementation with 25, 50, and 100 µM CA reduced the levels of intracellular
triglyceride (by 7.11%, 19.62%, and 31.57%) and total
cholesterol (by 8.46%, 23.32%, and 27.17%), and enhanced
glucose uptake (by 40.91%, 57.49%, and 61.32%) and intracellular
glycogen content (by 12.75%, 41.27%, and 53.77%). Moreover, CA supplementation downregulated the expression of
sterol regulatory
element-binding protein-1,
fatty acid synthase, and
stearoyl-CoA desaturase 1 related to lipogenesis while upregulating the expression of
carnitine palmitoyltransferase 1α related to
fatty acid oxidation. CA supplementation also upregulated the
glucose transporter 2
protein expression and phosphorylation of
glycogen synthase kinase 3β while downregulating the phosphorylation of
glycogen synthase. Most importantly, most of these effects of CA were reversed by pretreatment with
AMP-activated protein kinase (AMPK) inhibitor and
small interfering RNA-liver
kinase B1 (LKB1). In conclusion, CA ameliorated the
lipid and
glucose metabolism in PA-induced HepG2 cells via the LKB1/AMPK signaling pathway. PRACTICAL APPLICATION: In this study,
coniferaldehyde appeared to be effective in ameliorating hepatic
lipid and
glucose metabolism disorders in
nonalcoholic fatty liver disease by reducing the levels of intracellular
triglyceride and total
cholesterol and enhancing
glucose uptake and intracellular
glycogen content via the LKB1/AMPK signaling pathway in vitro. Therefore, our findings provide new evidence in support of that supplementation with
coniferaldehyde or food rich in
coniferaldehyde might be considered as a viable dietary intervention strategy for preventing and treating
nonalcoholic fatty liver disease.