AUTHOR=Ren Gang , Guo Jiang-Hong , Qian Yu-Zhen , Kong Wei-Jia , Jiang Jian-Dong 

TITLE=Berberine Improves Glucose and Lipid Metabolism in HepG2 Cells Through AMPKα1 Activation

JOURNAL=Frontiers in Pharmacology

VOLUME=11

YEAR=2020

URL=https://www.frontiersin.org/journals/pharmacology/articles/10.3389/fphar.2020.00647

DOI=10.3389/fphar.2020.00647

ISSN=1663-9812

ABSTRACT=<sec><title>Aim</title><p>This study is designed to investigate whether or not AMP-activated protein kinase α1 (AMPKα1) is required for natural product berberine (BBR) to improve glucose and lipid metabolism in HepG2 cells.</p></sec><sec><title>Methods</title><p>AMPKα1 knocked-out (KO, <italic>AMPKα1<sup>-/-</sup></italic>) cells were obtained by co-transfection of the CRISPR/Cas9 KO and HDR (homology-directed repair) plasmid into HepG2 cells, as well as subsequent screen with puromycin. The expression levels of target proteins or mRNAs were determined by western blot or real-time RT-PCR, respectively. Cellular AMPK activity, glucose consumption, lactate release, glucose production, and lipid accumulation were determined by kits.</p></sec><sec><title>Results</title><p>The results showed that the <italic>AMPKα1</italic> gene was successfully KO in HepG2 cells. In <italic>AMPKα1<sup>-/-</sup></italic> cells, the protein expression of AMPKα1 and phosphorylated-AMPKα1 (p-AMPKα1) disappeared, the level of total AMPKα declined to about 45–50% of wild type (<italic>p</italic> &lt; 0.01), while p-AMPKα level and AMPK activity were reduced to less than 10% of wild type (<italic>p</italic> &lt; 0.001). BBR increased p-AMPKα1, p-AMPKα, AMPK activity, and stimulated glucose consumption, lactate release, inhibited glucose production in wild type HepG2 cells (<italic>p</italic> &lt; 0.05 or <italic>p</italic> &lt; 0.01). BBR also reduced intracellular lipid accumulation and suppressed the expression of lipogenic genes in oleic acid (OA) treated wild type HepG2 cells (<italic>p</italic> &lt; 0.05 or <italic>p</italic> &lt; 0.01). In <italic>AMPKα1<sup>-/-</sup></italic> HepG2 cells, the stimulating effects of BBR on p-AMPKα1, p-AMPKα, AMPK activity, and its improving effects on glucose and lipid metabolism were completely abolished.</p></sec><sec><title>Conclusion</title><p>Our study proves that AMPKα1 plays a critical role for BBR to improve glucose and lipid metabolism in HepG2 cells. Our results will provide new information to further understand the molecular mechanisms of BBR.</p></sec>