Effective Dose of Alaska Pollack Protein for Increase of Muscle

Abstract

Abstract Objectives We have confirmed that the administration of Alaska pollack protein (APP) diet, which was totally substituted APP for casein (Cas) in the AIN-93 diet significantly increased rat skeletal muscle in 3 days after administration, compared to Cas-based control diet. But the administration of amino acid mixture, which of the equivalent amino acid composition to APP, was not effective in increasing skeletal muscle. It suggested that a protein or a degraded peptide of APP might be involved in the efficacy by administration of APP, but not the amino acids. In further study, we plan to investigate the effect of the administration of APP in the clinical trial. For estimation of the dosage for humans, we investigated the effective dose of APP for the skeletal muscle increasing effect of rat. Methods (1) Dietary administration (free intake): 6 weeks old male rats were administrated with the AIN-93 diet which were substituted APP for all, one third or one ninth of casein, or Cas-based control diet for 3 days. After administration, the gastrocnemius muscles of rat were evaluated. (2) Repeated oral administration: Cas and APP were orally administered at 1000 mg/kg and 333 mg/kg for 3 days. After administration, the gastrocnemius muscles of rat were evaluated. Results (1) Dietary administration: In the APP all and one-third administration group, mass of the gastrocnemius muscle increased significantly, and in the APP one ninth administration group was no significant difference. (2) Repeated oral administration: In the APP 333 mg/kg administration group, mass of the gastrocnemius muscle increased significantly. Although there was no significant difference, the mean of gastrocnemius muscle mass in the APP 1000 mg/kg group showed a value close to APP 333 mg/kg. Conclusions The increasing effect of APP on skeletal muscle was exerted in more than one-third APP substitution in dietary administration. Moreover, the effective amount of APP was 333 mg/kg or lower in repeated oral administration. It suggested that a protein or peptide was involved for the skeletal muscle increasing effect of APP, not amino acid balance. In addition, considering the application to humans, the human equivalent dose based on body surface area suggests that 53 mg/kg or more may be effective. This dose corresponds to about 30 g of Alaska pollack fillet daily. Funding Sources Nippon Suisan Kaisha, Ltd.