RESUMO
Targeting energy expenditure provides a potential alternative strategy for achieving energy balance to combat obesity and the development of type 2 diabetes mellitus (T2DM). In the present study, we investigated whether atractylenolide III (AIII) regulates energy metabolism in skeletal muscle cells. Differentiated C2C12 myotubes were treated with AIII (10, 20, or 50 µM) or metformin (2.5 mM) for indicated times. The levels of glucose uptake, the expressions of key mitochondrial biogenesis-related factors and their target genes were measured in C2C12 myotubes. AIII significantly increased the glucose uptake levels, and significantly increased the expressions of peroxisome proliferator-activated receptor coactivator-1α (PGC1α) and mitochondrial biogenesis-related markers, such as, nuclear respiratory factor-1 (NRF-1), and mitochondrial transcription factor A (TFAM) and mitochondrial mass and total ATP contents. In addition, AIII significantly increased the phosphorylation of AMP-activated protein kinase (AMPK) and the expression of sirtuin1 (SIRT1). These results suggest that AIII may have beneficial effects on obesity and T2DM by improving energy metabolism in skeletal muscle.
Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Metabolismo Energético/efeitos dos fármacos , Lactonas/farmacologia , Músculo Esquelético/efeitos dos fármacos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Extratos Vegetais/farmacologia , Sesquiterpenos/farmacologia , Sirtuína 1/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Atractylodes/química , Glicemia/metabolismo , Linhagem Celular , Proteínas de Ligação a DNA/sangue , Diabetes Mellitus Tipo 2/metabolismo , Proteínas de Grupo de Alta Mobilidade/sangue , Camundongos , Mitocôndrias/metabolismo , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/citologia , Músculo Esquelético/metabolismo , Fator 1 Nuclear Respiratório/sangue , Obesidade/metabolismo , FosforilaçãoRESUMO
OBJECTIVE: To evaluate the effect of ethyl pyruvate (EP) in improving the survival and ameliorating distant organ damage and to investigate the role of high-mobility group box (HMGB) 1 in rats with established severe acute pancreatitis (SAP). METHODS: Severe acute pancreatitis was induced by retrograde infusion of sodium taurodeoxycholate (5%, 1 mL/kg) into the biliopancreatic ducts in male Wistar rats. The rats were infused intravenously with EP of 40 mg/kg, 4 mg/kg, and 0.4 mg/kg initiating 12 hours, and EP of 40 mg/kg was administered beginning 2 hours before surgery (-2 hours) and 12, 24, and 36 hours after induction of SAP; then, the mortality was recorded. Serum tumor necrosis factor alpha, interleukin (IL) 6, and IL-1beta were measured using enzyme-linked immunosorbent assay. High-mobility group box 1 levels were measured using Western immunoblotting analysis. RESULTS: Serum HMGB1 levels were increased dramatically after 12 hours, remained at high levels for 72 hours, and were significantly higher in rats with SAP than in those with mild and moderate pancreatitis (P < 0.01). Treatment with EP (40 mg/kg) conferred protection from lethality of SAP (EP survival [63%] vs vehicle survival [6.3%]; P < 0.001). No survival advantage occurred when treatment was initiated 36 hours after surgery, but administration beginning 2 hours before operation (-2 hours) and 12 and 24 hours after induction of SAP significantly increased survival. Ethyl pyruvate treatment significantly decreased serum HMGB1, tumor necrosis factor alpha, IL-1beta, and IL-6 levels and ameliorated extrapancreatic organ dysfunction in rats with SAP. CONCLUSIONS: Ethyl pyruvate improves survival and ameliorates distant organ injury of SAP. These beneficial effects of EP are because of the modulation of HMGB1 and other inflammatory cytokine responses.