Composition of Gomori‐positive inclusions in astrocytes of the hypothalamic arcuate nucleus

  title={Composition of Gomori‐positive inclusions in astrocytes of the hypothalamic arcuate nucleus},
  author={James R. Brawer and R Stein and Lorne Small and Soriba Ciss{\'e} and Hyman M. Schipper},
  journal={The Anatomical Record},
Background: Astrocytes within the hypothalamic arcuate nucleus contain Gomori‐positive inclusions that exhibit a nonenzymatic peroxidase activity. The source and composition of these Gomori‐positive inclusions are currently unknown. Recent evidence, derived from cultured astrocytes, suggests that Gomori‐positive inclusions may consist of autophagocytized accumulations of altered mitochondria and that the peroxidase activity is generated by iron or other metals which accumulate in these… 
Immunoreactivity for brain‐fatty acid binding protein in gomori‐positive astrocytes
Gomori‐positive (GP) astrocytes are a subset of brain astro cytoplasmic granules that arise from the degradation of mitochondria that can be detected in the olfactory bulbs, hippocampus, habenula, and other selected brain regions.
GLUT2 Immunoreactivity in Gomori-positive Astrocytes of the Hypothalamus
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  • Biology
    The journal of histochemistry and cytochemistry : official journal of the Histochemistry Society
  • 2004
The possibility that Gomori-positive astrocytes may have an important influence upon the reactivity of the hypothalamus to glucose and that a specialized glucose metabolism may in part underlie the development of mitochondrial abnormalities in hypothalamic GP astroCytes is supported.
Astrocyte Mitochondria: A Substrate for Iron Deposition in the Aging Rat Substantia Nigra
Histochemical, ultrastructural, and elemental microanalytical techniques were used to demonstrate the existence of peroxidase-positive astroglia in the substantia nigra of adult rats, and mitochondrial sequestration of redox-active iron in aging nigral astrogalia may be one factor predisposing the senescent nervous system to parkinsonism and other neurodegenerative disorders.
Mitochondrial constituents of corpora amylacea and autofluorescent astrocytic inclusions in senescent human brain
Corpora amylacea (CA) are cytoplasmic inclusions that accumulate in human brain in the course of normal aging, and to an even greater extent, in Alzheimer's disease and other neurodegenerative
Using electron spin resonance spectroscopy, it is demonstrated that CSH-induced astrocyte peroxidase activity catalyzes the robust oxidation of 2-hydroxyestradiol to its ortho-semiquinone radical lending further credence to the Free Radical Hypothesis of estradiol neurotoxicity.
Cysteamine Pretreatment of the Astroglial Substratum (Mitochondrial Iron Sequestration) Enhances PC12 Cell Vulnerability to Oxidative Injury
The aging-associated accumulation of redox-active iron in subcortical astrocytes may facilitate the bioactivation of dopamine to neuronotoxic free radical intermediates and thereby predispose the senescent nervous system to PD and other neurodegenerative disorders.
Iron: Oxidative Stress and Neurodegeneration
CSH attenuates de novo porphyrin-heme biosynthesis in astroglia but may induce punctate orange-red autofluorescence in the cytoplasm of these cells by promoting large numbers of damaged, porphirin-containing mitochondria to form tight aggregates within the nascent gliosomes.
Role of Porphyrin Sequestration in the Biogenesis of Iron-Laden Astrocytic Inclusions in Primary Culture
Astrocytes in subcortical regions of the mammalian brain progressively accumulate iron-rich, autofluorecent cytoplasmic inclusions as a function of aging. Cysteamine (CSH) accelerates the appearance
Experimental induction of corpora amylacea in adult rat brain
  • H. Schipper
  • Biology
    Microscopy research and technique
  • 1998
This study shows that subcutaneous administration of CSH to adult rats elicits the accumulation of CA in many cortical and subcortical brain regions, and supports the contention that mitochondria are important structural precursors of CA, and that CSH accelerates aging‐like processes in rat astroglia both in vitro and in the intact brain.
A Cellular Stress Model for the Sequestration of Redox‐Active Glial Iron in the Aging and Degenerating Nervous System
The results of this study suggest that stress‐related trapping of nonheme iron by astroglial mitochondria may be an important mechanism underlying the pathological accumulation of redox‐active iron in the basal ganglia of subjects with Parkinson's disease.


Structural and cytochemical changes in astrocytes from the brain periventricular zone of the copper‐deficient blotchy mouse
The findings described are possibly due to defective copper metabolism in mottled mutants which may include a number of other related abnormalities, including reduced activity of copper‐dependent enzymes such as porphyrin‐containing peroxidases.
Studies on the structure and function of Gomori-positive glial cells in the rat hypothalamus.
There was a considerable decrease in GP grains after administration of estradiol in ovariectomized rats and also in pregnant rats and the possible participation of GP glia in the neuroendocrinological process is discussed.
Gomori‐positive astrocytes: Biological properties and implications for neurologic and neuroendocrine disorders
Gomori‐positive astrocytes may supply heme to neurons for the synthesis of cytochromes, catalases, and other heme enzymes, and play a role in photostimulation of sexual cyclicity, the promotion of neuritic development, the degradation of toxic lipoperoxides, and the metabolism of various neurotransmitters.
Catechol oxidation by peroxidase-positive astrocytes in primary culture: an electron spin resonance study
Robust peroxidase-catalyzed oxidation of 2-hydroxyestradiol and dopamine is demonstrated by cysteamine-pretreated astrocyte cultures relative to untreated controls, implicate the peroxIDase-positive astrotytes in the pathogenesis of estradiol-related hypothalamic damage, parkinsonism, and other free-radical-related neurologic disorders.
Iron content correlates with peroxidase activity in cysteamine-induced astroglial organelles.
The presence and concentration of iron in these organelles correlated closely with the presence and intensity of diaminobenzidine staining, suggesting that redox-active iron mediates the pseudoperoxidase reactions in these cells.
Ovary-dependent degeneration in the hypothalamic arcuate nucleus.
The fact that monthly injections of estradiol valerate in male rats produced the same profile of degeneration in the arcuate nucleus suggests that the neuropathological agent may itself be estradio, which may be capable of gradually producing an arcuate lesion.
Cytopathological effects of estradiol on the arcuate nucleus of the female rat. A possible mechanism for pituitary tumorigenesis.
It is possible that, in addition to its effects on the hypophysis, EV suppresses or injures hypophysiotropic cells in MBH, thus releasing pituitary chromophobes from inhibitory hypothalamic influences, which could result in hypersecretion and neoplasia.