ABSTRACT
Background@#Dual-energy X-ray absorptiometry (DXA) is the most widely used method for evaluating muscle masses. The aim of this study was to investigate the agreement between muscle mass values assessed by two different DXA systems. @*Methods@#Forty healthy participants (20 men, 20 women; age range, 23 to 71 years) were enrolled. Total and regional body compositional values for fat and lean masses were measured consecutively with two DXA machines, Hologic Horizon and GE Lunar Prodigy. Appendicular lean mass (ALM) was calculated as the sum of the lean mass of four limbs. @*Results@#In both sexes, the ALM values measured by the GE Lunar Prodigy (24.8±4.3 kg in men, 15.8±2.9 kg in women) were significantly higher than those assessed by Hologic Horizon (23.0±4.0 kg in men, 14.8±3.2 kg in women). Furthermore, BMI values or body fat (%), either extremely higher or lower levels, contributed greater differences between two systems. Bland-Altman analyses revealed a significant bias between ALM values assessed by the two systems. Linear regression analyses were performed to develop equations to adjust for systematic differences (men: Horizon ALM [kg]=0.915×Lunar Prodigy ALM [kg]+0.322, R2=0.956; women: Horizon ALM [kg]=1.066×Lunar Prodigy ALM [kg]–2.064, R2=0.952). @*Conclusion@#Although measurements of body composition including muscle mass by the two DXA systems correlated strongly, significant differences were observed. Calibration equations should enable mutual conversion between different DXA systems.
ABSTRACT
Background@#Glucagon-like peptide-1 (GLP-1) analogues regulate glucose homeostasis and have anti-inflammatory properties, but cause gastrointestinal side effects. The fibroblast growth factor 21 (FGF21) is a hormonal regulator of lipid and glucose metabolism that has poor pharmacokinetic properties, including a short half-life. To overcome these limitations, we investigated the effect of a low-dose combination of a GLP-1 analogue and FGF21 on atherosclerosis-related molecular pathways. @*Methods@#C57BL/6J mice were fed a high-fat diet for 30 weeks followed by an atherogenic diet for 10 weeks and were divided into four groups: control (saline), liraglutide (0.3 mg/kg/day), FGF21 (5 mg/kg/day), and low-dose combination treatment with liraglutide (0.1 mg/kg/day) and FGF21 (2.5 mg/kg/day) (n=6/group) for 6 weeks. The effects of each treatment on various atherogenesisrelated pathways were assessed. @*Results@#Liraglutide, FGF21, and their low-dose combination significantly reduced atheromatous plaque in aorta, decreased weight, glucose, and leptin levels, and increased adiponectin levels. The combination treatment upregulated the hepatic uncoupling protein-1 (UCP1) and Akt1 mRNAs compared with controls. Matric mentalloproteinase-9 (MMP-9), monocyte chemoattractant protein-1 (MCP-1), and intercellular adhesion molecule-1 (ICAM-1) were downregulated and phosphorylated Akt (p-Akt) and phosphorylated extracellular signal-regulated kinase (p-ERK) were upregulated in liver of the liraglutide-alone and combination-treatment groups. The combination therapy also significantly decreased the proliferation of vascular smooth muscle cells. Caspase-3 was increased, whereas MMP-9, ICAM-1, p-Akt, and p-ERK1/2 were downregulated in the liraglutide-alone and combination-treatment groups. @*Conclusion@#Administration of a low-dose GLP-1 analogue and FGF21 combination exerts beneficial effects on critical pathways related to atherosclerosis, suggesting the synergism of the two compounds.