Digital imaging analysis for the study of endotoxin-induced mitochondrial ultrastructure injury

Primary defects in mitochondrial function have been implicated in over 100 diverse diseases. In situ, mitochondria possess unique and well-defined mor phology in normal healthy cells, but diseases linked to defective mitochond rial function are characterized by the presence of morphologically abnormal and swollen mitochondria with distorted cristae. In situ study of mitochon drial morphology is established as an indicator of mitochondrial health but thus far assessments have been via subjective evaluations by trained obser vers using discontinuous scoring systems. Here we investigated the value of digital imaging analysis to provide for unbiased, reproducible, and conven ient evaluations of mitochondrial ultrastructure. Electron photomicrographs of ileal mucosal mitochondria were investigated using a scoring system pre viously described by us, and also analyzed digitally by using six digital p arameters which define size, shape, and electron density characteristics of over 700 individual mitochondria. Statistically significant changes in mit ochondrial morphology were detected in LPS treated animals relative to vehi cle control using both the subjective scoring system and digital imaging pa rameters (p < 0.05). However, the imaging approach provided convenient and high throughput capabilities and was easily automated to remove investigato r influences. These results illustrate significant changes in ileal mucosal mitochondrial ultrastructure during sepsis and demonstrate the value of di gital imaging technology for routine assessments in this setting.