Does proteolysis explain glutamine release from the septic brain?

Berg and colleagues report on amino acid exchange across the human brain during endotoxin infusion. Lipopolysaccharide infusion induced a decrease in the ratio between branched chain amino acids and aromatic amino acids, increased unidirectional phenylalanine uptake, and increased net brain glutamine release. Cerebral proteolysis is suggested to play a role, but the question is whether this is the case and why this would happen.