The low expression level of elongation factor Tu in the livers of ketotic cows indicates decreased levels of protein synthesis due to the limited availability of amino acids, because the most glucogenic amino acids
sustain the glyconeogenesis pathway; thus increasing the level of alpha-enolase.
On the other hand, amino acids broken down to pyruvate, a-ketoglutarate, succinyl CoA, fumarate, or oxaloacetate are termed glucogenic amino acids
. Pyruvate is the entry point of the three-carbon amino acids like L-alanine (L-Ala), L-serine (L-Ser), and L-cysteine (L-Cys) into the metabolic mainstream.
When lactate and glucogenic amino acids
are more available for other synthetic processes, propionate could preferentially be used for gluconeogenesis [2,32], increasing the proportion of glucose derived from propionate.
The high protein and fat densities of usual cat diets ensure that cats consuming these diets have adequate glucogenic precursors (glucogenic amino acids
and glycerol, respectively).
Besides, alanine, isoleucine, and valine are glucogenic amino acids
. The increase in these amino acids indicated that gluconeogenesis was suppressed in case of acute liver damage, partly explaining the decreased glucose level.