c-Met Modulates RPE Migratory Response to Laser-Induced Retinal Injury

Retinal laser injuries are often associated with aberrant migration of the retinal pigment epithelium (RPE), which can cause expansion of the scar beyond the confines of the original laser burn. In this study, we devised a novel method of laser-induced injury to the RPE layer in mouse models and began to dissect the mechanisms associated with pathogenesis and progression of laser-induced RPE injury. We have hypothesized that the proto-oncogene receptor, c-Met, is intimately involved with migration of RPE cells, and may be an early responder to injury. Using transgenic mouse models, we show that constitutive activation of c-Met induces more robust RPE migration into the outer retina of laser-injured eyes, while abrogation of the receptor using a cre-lox method reduces these responses. We also demonstrate that retinal laser injury increases expression of both HGF and c-Met, and activation of c-Met after injury is correlated with RPE cell migration. RPE migration may be responsible for clinically significant anatomic changes observed after laser injury. Abrogation of c-Met activity may be a therapeutic target to minimize retinal damage from aberrant RPE cell migration

Hemoglobin Regeneration and Distribution of Iron, Copper and Zinc in Hepatic Subcelluler Frantions of Rats Fed With Tempe Diets

ABSTRAK Hemoglobin regeneration efficiency was used to predict the iron availability of tempe diet by the method of depletion and repletion using rats for animal experiment. Hemoglobin regeneration efficiency of tempe showed the same effect with casein diet and unfermented soybean diet indicating that iron from soybeans are a good source of available iron. Iron, copper, and zinc from casein, unfermented soybean and tempe diets were distributed in hepatic subcelluler fractions in the same pattern. The highest level of iron and zinc were found in the cytosolic fraction and copper was found in the nuclear fraction. The different pattern among those trace minerals indicates that they have distinct roles in hemoglobin synthesis and metabolism. Keywords: hemoglobin synthesis, animal experimen