Comparative Effects Of Fasting And Acute Exercise On Lipid Synthesis And Degradation In NAFLD Mice Liver

PURPOSE: Fasting and exercise are effective nonpharmacological ways to control body weight and suppress lipid deposition. This study investigated the effect of fasting and acute exercise on liver de novo lipid synthesis and lipid droplet decomposition in mice with nonalcoholic fatty liver disease. METHODS: Forty male C57BL/6 J mice were randomly divided into four groups: ND (normal diet), HC (high-fat, high-fructose and high-cholesterol diet), HF (HC diet with 24 h fasting), and HE (HC diet with acute exercise) groups (n = 10).Liver tissues were taken for TG and FFA detection. Western blot was used to detect the expression levels of lipid droplet synthesis and lipolysis related proteins (SREBP,PLIN2,ATGL).The remaining liver samples were sectioned for immunofluorescence staining of SREBP, and calculate the Mandel's coefficients of ATGL and PLIN2. RESULTS: 1)ND vs HC, TG and FFA were significantly increased (0.07 ± 0.02vs0.19 ± 0.05 mg/g,6.55 ± 0.91vs13.90 ± 4.09 μmol/g);as well as PLIN2, SREBP levels and its nuclear translocation (0.67 ± 0.41vs3.66 ± 0.90,0.44 ± 0.12vs0.77 ± 0.11,0.50 ± 0.15vs0.73 ± 0.12%);ATGL level and the Mandel's coefficients of ATGL and PLIN2(0.51 ± 0.05vs0.98 ± 0.10,0.03 ± 0.02vs0.39 ± 0.10)(p < 0.05). 2)HC vs HF,TG and FFA were significantly decreased(0.12 ± 0.05 mg/g,6.45 ± 3.08 μmol/g)(p < 0.05),as well as SREBP nuclear translocation(0.49 ± 0.20%)(p < 0.05),the expressions of PLIN2 show a downward trend;The observation on Mandel's coefficients of ATGL and PLIN2(0.59 ± 0.06)(p < 0.05),the lipolysis level was significantly increased.3)HC vs HE,TG and FFA were significantly decreased(0.12 ± 0.04 mg/g,8.07 ± 1.96 μmol/g),as well as PLIN2, SREBP levels and its nuclear translocation nuclear translocation(1.37 ± 0.88,1.23 ± 0.25,0.48 ± 0.25%),ATGL level(0.32 ± 0.10),while the Mandel's coefficients of ATGL and PLIN2 was no significant difference(p < 0.05). CONCLUSIONS: Both fasting and acute exercise can effectively reduce vigorous lipid droplet formation in NAFLD mice. While lipolysis of lipid droplets is more radical during fasting than acute exercise. Supported by: This study was supported by Higher Education Institutions in Jiangsu Province (24KJA310002),Youth Project of National Natural Science Foundation of China (32000839),College Students' Innovation and Entrepreneurship Training Program Projects of Higher Education Institutions in Jiangsu Province(202410330004Z)