The metabolic effects of post-sepsis feeding of meals with only essential amino acids.

Nutritional support is a vital component of the rehabilitation process following sepsis. Essential amino acids (EAA) are recognized as a critical component for stimulating anabolism. However, it remains unclear whether EAA supplementation alone is more effective than providing a complete profile of total amino acids (TAA). We studied amino acid (AA) metabolism in 51 catheterized pigs (±27 kg) using the pulse tracer approach over a 7-day recovery period following sepsis. Animals were randomly and blindly assigned to receive post-sepsis nutrition containing either an EAA or a TAA mixture based on the composition of pig muscle. Statistical analyses were performed using a generalized linear mixed model. Plasma concentrations of EAA increased substantially in the EAA group post-sepsis (interaction effect, P<0.001), while those of non-essential AA increased in both groups (time effect, P<0.001). Whole-body intracellular production of most AA was reduced on day 3 and remained low on day 7 post-sepsis, with only small differences observed between the two groups. On day 7 post-sepsis, pigs receiving only EAA showed significantly (all P<0.001) lower intracellular production of hydroxyproline (-36%), ornithine (-11%), and tryptophan (-20%) and higher production of arginine (66%), citrulline (18%), glutamine (18%), taurine (22%), and some EAA. The EAA group showed a significantly higher net protein breakdown post-sepsis. In this sepsis-recovery pig model, dietary supplementation of both EAA and TAA failed to normalize the intracellular production of AA. More importantly, providing only EAA resulted in a significantly greater net protein breakdown compared with the TAA group.