The efficiency of oral leucine administration on the progressing of melanoma in a murine sarcopenic model

抄録

It has been known that sarcopenia causes the immune dysfunction. In this study, we evaluated the influence of the sarcopenia on the progression of melanoma using a denervation-induced sarcopenic model and the efficacy of leucine-intervention was evaluated. 

Initially, the influences of leucine-intake on maintaining immune homeostasis were observed. The expression of PD1 on CD4-positive T cells and CD8-positive T cells increased in the sarcopenia mice comparing those in control mice. Then, a diet-intake leucine was orally administrated to both sarcopenic mice and melanoma-implanted sarcopenic mice. The administration of leucine caused an elevation of total CD4-positive cells and significantly decreased the number of PD1+CD4+ fraction and PD1+CD8+ fraction in sarcopenic mice. The subpopulation of PD1+CD8+ fraction in leucine-treated sarcopenic mice was even much lower than that in non-sarcopenic group. The Kaplan-Meier curve also suggests that leucine-intake potentially increased the survival rates in sarcopenic mice. 

Taken together, the results obtained from the present study suggests that oral administration of leucine can restore the skeletal muscle mass and may affect the onset of cancer progression via improving the function of immunological defense. It would benefit the management of melanoma in sarcopenic patients.