7.3B: Adipose Macronutrient Metabolism

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It probably does not surprise you that the major function of the adipose is to store energy as triglycerides. Compared to extrahepatic tissues as a whole, in the adipose the following pathways are not performed or are not important:

Glycogen synthesis and breakdown
Lactate synthesis
Ketone body breakdown
Fatty acid breakdown
Protein synthesis and breakdown
Citric acid cycle (not much since it is not an active tissue needing energy)

These pathways are crossed out in the figure below.

Figure 7.321.png

Figure 7.321 The metabolic pathways that are not performed or important in the adipose, compared to extrahepatic tissues as a whole are crossed out¹

Removing those pathways, we are left with metabolic capabilities listed below and depicted in the following figure:

Glycolysis
Fatty acid synthesis

Triglyceride synthesis and breakdown

Figure 7.322.png

Figure 7.322 Adipose metabolic capability

Fatty acid synthesis only occurs in the adipose and liver. In the adipose, fatty acids are synthesized and most will be esterified into triglycerides to be stored. In the liver, some fatty acids will be esterified into triglycerides to be stored, but most triglycerides will be incorporated into VLDL so that they can be used or stored by other tissues.

References & Links

en.Wikipedia.org/wiki/File:CellRespiration.svg