Reciprocal Glycerolipid Syntheses in Skeletal Muscle of Obese Rats

Introduction

Intramyocellular triglyceride (imcTG) levels in skeletal muscle are known to be abnormally high in obesity and type 2 diabetes, and excess imcTG is a strong predictor of insulin resistance [1] [2] [3]. On the other hand, the pathways underlying excess imcTG accumulation remain unknown. Since synthesis is the initial step in imcTG accumulation, imcTG synthesis may be accelerated in obesity. Meanwhile, since glycerol is a common precursor in the synthesis of both triglycerides and phospholipids, increased imcTG synthesis may also affect the phospholipid metabolism. We have tested the hypothesis using the high-fat-fed rat obesity model and ¹⁴C-glycerol as a tracer based on our previous findings that glycerol is the main precursor for imcTG synthesis in fasted rats [4].

References

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