ABSTRACT
Casein kinase 2 (CK2) is a ubiquitously expressed serine/threonine kinase and is upregulated in human obesity. CX-4945 (Silmitasertib) is a CK2 inhibitor with anti-cancerous and anti-adipogenic activities. However, the anti-adipogenic and pro-lipolytic effects and the mode of action of CX-4945 in (pre)adipocytes remain elusive. Here, we explored the effects of CX-4945 on adipogenesis and lipolysis in differentiating and differentiated 3T3-L1 cells, a murine preadipocyte cell line. CX-4945 at 15 µM strongly reduced lipid droplet (LD) accumulation and triglyceride (TG) content in differentiating 3T3-L1 cells, indicating the drug's anti-adipogenic effect. Mechanistically, CX-4945 reduced the expression levels of CCAAT/enhancer-binding protein-α (C/EBP-α), peroxisome proliferator-activated receptor-γ (PPAR-γ), fatty acid synthase (FAS), acetyl-CoA carboxylase (ACC), and perilipin A in differentiating 3T3-L1 cells. Strikingly, CX-4945 further increased the phosphorylation levels of cAMP-activated protein kinase (AMPK) and liver kinase B-1 (LKB-1) while decreasing the intracellular ATP content in differentiating 3T3-L1 cells. In differentiated 3T3-L1 cells, CX-4945 had abilities to stimulate glycerol release and elevate the phosphorylation levels of hormone-sensitive lipase (HSL), pointing to the drug's pro-lipolytic effect. In addition, CX-4945 induced the activation of extracellular signal-regulated kinase-1/2 (ERK-1/2), and PD98059, an inhibitor of ERK-1/2, attenuated the CX4945-induced glycerol release and HSL phosphorylation in differentiated 3T3-L1 cells, indicating the drug's ERK-1/2-dependent lipolysis. In summary, this investigation shows that CX-4945 has strong anti-adipogenic and pro-lipolytic effects on differentiating and differentiated 3T3-L1 cells, mediated by control of the expression and phosphorylation levels of CK2, C/EBP-α, PPAR-γ, FAS, ACC, perilipin A, AMPK, LKB-1, ERK-1/2, and HSL.
Subject(s)
Adipogenesis , Casein Kinase II , Naphthyridines , Phenazines , 3T3-L1 Cells , AMP-Activated Protein Kinases/metabolism , Animals , CCAAT-Enhancer-Binding Protein-alpha/metabolism , Casein Kinase II/antagonists & inhibitors , Casein Kinase II/metabolism , Cell Differentiation/drug effects , Cyclic AMP-Dependent Protein Kinases/metabolism , Glycerol/pharmacology , Humans , Lipolysis/drug effects , Mice , Naphthyridines/pharmacology , PPAR gamma/metabolism , Perilipin-1/metabolism , Phenazines/pharmacology , Sterol Esterase/metabolismABSTRACT
Obesity is becoming a global epidemic as a result of high-calorie food intake and unhealthy lifestyles. Different marine plants, especially brown algae (Ecklonia cava), are traditionally used to treat different health-related issues. The study was carried out to investigate the anti-obesity properties of E. cava 70% ethanol extract. To evaluate the anti-obesity effect of E. cava, both in vitro and in vivo tests were performed. E. cava suppresses pre-adipocyte 3T3-L1 differentiation in a dose-dependent manner. In HFD-induced obese rats' models, administration of E. cava 125, 250, and 500 mg/kg significantly decreases total body weight and organs, especially liver weight, in all treatment groups. Adipose tissue weight, including subcutaneous, epididymal, peritoneal, and mesenteric adipose tissue, was markedly reduced in E. cava-treated HFD rats in dose-dependent manners. In addition, liver-related biomarkers AST, ALP, ALT, and GGT were evaluated; the lower level of liver-related biomarkers indicates no liver injury or fatty liver issue in E. cava HFD treatment groups. In addition, E. cava treatment has significant effects on the expression of adipogenic and lipogenic (PPAR-γ, FAS, LPL, and SREBP-1c) genes. Altogether, these results show the anti-obesity effect of E. cava. We concluded that E. cava could be a potential candidate for the prevention of obesity-induced by a high-fat diet.