Effects of Parenteral Amino Acid Administration on the Postoperative Nutritional Status and Wound Healing of Protein-Malnourished Rats

Abstract

In Japan, parenteral nutrition (PN) solutions are frequently administered to patients in the postoperative short-term period. In these cases, amino acid-containing peripheral parenteral nutrition (PPN) solutions, amino acid-free maintenance solutions or combinations of the two are used. However, consensus regarding the most beneficial solution for these patients is lacking. Here, we examined the nutritional status and wound healing outcomes in protein-malnourished rats receiving postoperative administrations of PPN solution, maintenance solution or combinations of the two solutions. Protein malnutrition was induced in Sprague-Dawley rats by feeding an AIN-93G-based low-protein diet (5% casein) for 2 wk. After laparotomy, dorsal skin incision, and placement of a jugular vein catheter, the rats were divided into 3 groups. Each group was administered 113 kcal/kg/d, with group A receiving maintenance solutions without amino acid, group B receiving PPN with 1.5% amino acid, and group C receiving PPN with 3% amino acid. After 5 d post-operative administration, we measured the tensile strength of the wound area, skeletal muscle weights, and nutritional parameters. Significantly higher plasma nutritional parameters and gastrocnemius and extensor digitorum longus (EDL) muscle weights were observed in groups B and C than in group A. Group C exhibited significantly elevated tensile strength of the wound area along with up-regulation of type I collagen mRNA expression compared to group A. These findings demonstrate the nutritional status and wound healing benefits of short-term postoperative administration of PPN solutions containing amino acids in protein-malnourished rats.

Influence of protein malnutrition on cutaneous wound healing in rats

“…Thus, the observed transformations in the connective tissue matrix suggest that balanced nutrition represents a determining factor for establishing a good healing pattern. Others studies also have similar results and described worse wound healing in malnourished animals [29,30].…”

The Effect of a Compound Protein on Wound Healing and Nutritional Status

“…Therefore, administering compound proteins in rats could accelerate wound healing and improve nutritional status compared to providing nothing in addition to basic energy intake in the early period of trauma. In a previous study, Akira et al found that administering peripheral parenteral nutrition (PPN) solutions containing amino acids immediately after surgery is efficacious for wound healing [ 14 ]. Furthermore, Oishi et al reported that protein malnutrition could deteriorate skin conditions [ 15 ].…”

Hot spring bathing accelerates wound healing and enhances heat retention effect in guinea pigs

“…It has been reported that the supply of amino acids is effective for wound healing [ 5 , 66 , 67 , 77 ], whereas amino acid deficiency delays wound healing [ 6 , 8 , 87 ]. It is also known that plasma amino acid levels were elevated when wound healing was promoted by amino acid supply [ 51 , 85 ]. Several studies in humans and animals without wounds have also indicated the possibility that hot spring bathing alters the metabolism of biological materials such as hormones and proteins [ 3 , 18 , 25 , 86 ].…”