Lysosome-induced damage in the human edematous cerebral cortex. An electron microscopic study.
Abstract
The lysosome-induced alterations on cortical nerve cells were examined in the anoxic-ischemic brain parenchyma of thirty-one patients with congenital hydrocephalus, complicated brain traumatic injuries, brain tumours and vascular anomalies. Cortical biopsies of frontal, parietal, and temporal cortex taken during neurosurgical treatment were processed for conventional transmission electron microscopy. The lysosomes showed fragmentation of limiting membrane and an associated dense granulation. Areas of cytoplasmic focal necrosis were observed surrounding the lysosomes, suggesting the release of lysosomal enzymes. Lipofucsin granules were observed in infant patients with congenital hydrocephalus suggesting that Lipofucsin formation is a lifespan process. An increased amount of lipofucsin granules was observed in young and adult patients with brain trauma, brain tumours and vascular anomalies. The brain trauma-induced activation of
oligodendroglial and astrocytes cells, which showed the overall spectrum of an altered endosomal-lysosomal system and phagocytic activity. The role of oxidative stress is emphasized in the damage of lysosomal limiting membrane and the role of activated lysosomal enzymes is discussed in relation with the fragmentation of plasma membrane, and focal cytoplasmatic necrosis of nerve cells.