Oral administration of C-14 labeled gelatin hydrolysate leads to an accumulation of radioactivity in cartilage of mice (C57/BL)

Several investigations showed a positive influence of orally administered g elatin on degenerative diseases of the musculo-skeletal system. Both the th erapeutic mechanism and the absorption dynamics, however, remain unclear. T herefore, this study investigated the time course of gelatin hydrolysate ab sorption and its subsequent distribution in various tissues in mice (C57/BL ). Absorption of C-14 labeled gelatin hydrolysate was compared to control m ice administered C-14 labeled proline following intragastric application. P lasma and tissue radioactivity was measured over 192 h. Additional "gut sac " experiments were conducted to quantify the MW distribution of the absorbe d gelatin using SDS-electrophoresis and HPLC. Ninety-five percent of entera lly applied gelatin hydrolysate was absorbed within the first 12 h. The dis tribution of the labeled gelatin in the various tissues was similar to that of labeled proline with the exception of cartilage, where a pronounced and long-lasting accumulation of gelatin hydrolysate was observed. In cartilag e, measured radioactivity was more than twice as high following gelatin adm inistration compared to the control group. The absorption of gelatin hydrol ysate in its high molecular form, with peptides of 2.5-15kD, was detected f ollowing intestinal passage. These results demonstrate intestinal absorptio n and cartilage tissue accumulation of gelatin hydrolysate and suggest a po tential mechanism for previously observed clinical benefits of orally admin istered gelatin.