Thalamic degeneration in X-chromosome--linked copper malabsorption

Histochemical localization of copper in various organs of brindled mice after copper therapy

Copper (Cu) distribution in various organs of brindled mice (BM), an animal model of Menkes disease, was studied histochemically and by atomic-absorption-spectrophotometry 7 months after Cu injections. The results were compared with those of untreated BM. In the treated BM brain, a diffuse reduction in Cu-related staining of neurons and astroglia was still evident, though it had improved to some extent. The reduction was noticeable in the thalamus, brain stem and cerebellum, although intensely stained capillaries were noted occasionally in the retrosplenial and mediobasal temporal areas, including the hippocampus. In the treated BM liver, near normalization of Cu distribution was observed. In the treated BM intestine, the main localization of Cu accumulation was in histiocytes/macrophages in the lamina propria, while in the untreated BM it was in the absorptive and secretory epithelial cells. In the treated BM kidney, there was no clear improvement in Cu distribution. These histochemical results were consistent with the data obtained by the spectrophotometric assay. Electron microscopic histochemistry of affected renal tubular epithelial cells revealed numerous silver grains, which represent Cu++ localization, distributed only within the cytoplasm outside organella and nucleus. This suggests impaired intracellular Cu transport from cytosol to organella, which in the kidney is refractory to the Cu therapy adopted.

Cytochrome C oxidase deficiency and neuronal involvement in Menkes' kinky hair disease: immunohistochemical study

Antibodies against subunits II and IV of cytochrome c oxidase (COX) and against complex III of the respiratory chain were used to study the expression of these proteins in the cerebellum, spinal cord, and other regions of the central nervous system in an autoptic case of Menkes' kinky hair disease (MKHD). We found a reduced expression of COX subunits in all examined areas whereas staining for complex III appeared normal. Immunostaining was altered in morphologically well-preserved neurons, suggesting that COX deficiency may have a pathogenetic role in the neuronal degeneration of MKHD.

Menkes' kinky hair disease: morphological and immunohistochemical comparison of two autopsied patients

An autopsied patient with Menkes' kinky hair disease, who showed unusually long survival until the age of five years with typical neuropathological changes, was examined for distribution of neuronal depletion in the cerebral cortex, and the cerebellar changes were compared morphologically and immunohistochemically with those found in a younger patient (1 year 8 months old) reported previously. Neuronal loss in the cerebral cortex in the both cases, which was ill-defined and unassociated with gliosis, was preferentially distributed in the fifth and sixth layers, especially of the gyral bottom in almost all lobes in the older case. Therefore, this change was thought to be secondary to local ischemia caused by mechanical distortion at the stage of gyrus formation in addition to abnormal development. Ultrastructurally, a prominent increase of confronting cisternae (CC) complexes was found in the perikaryon and processes of Purkinje cells in both cases, and in the older patient CC complexes were arranged more densely and were transformed into concentric lamellar structures in the swollen dendrites. Immunohistochemically, the stainability of neurofilaments (NF, 200 kDa) in Purkinje cells, with or without somatic sprouts was faint or negative in the older patient compared with the marked or moderate positivity in the younger patient and age-matched controls. Empty baskets were absent and NF-positive axonal terminals and synaptophysin-positive granules on Purkinje cells were markedly decreased in both cases. These changes suggest that Purkinje cells degenerate progressively with time and that basket cells also are simultaneously involved.

Neuronal and vascular disorders of the brain and spinal cord in Menkes kinky hair disease

A 3 2/12-year-old boy had recurrent seizures, chronic respiratory infection, and delayed physical and mental development. He also had low plasma copper content typical of Menkes syndrome. Autopsy showed marked neuronal loss and gliosis in most areas of the cerebral and cerebellar cortices, midbrain, pons, and medulla. The spinal cord showed severe demyelination in both ascending (spinocerebellar) and descending (lateral corticospinal) tracts from the cervical to the sacral level. In addition to these neuronal lesions, both the meningeal and parenchymal arterial and venous branches were remarkably dilated in the brain and spinal cord. Our previous study of this case showed abnormal perivascular innervation and abnormal axonal swelling of the postganglionic adrenergic fibers elsewhere in the body. The metabolic disorder caused by copper deficiency induces severe neuronal degeneration that is apparently exaggerated by extensive and progressive vascular abnormality.

Menkes' disease and swayback. A comparative study of two copper deficiency syndromes

The neuropathological findings in two siblings with Menkes' disease were compared with representative material obtained from lambs suffering from swayback (enzootic ataxia). The aim of the study was to demonstrate the similarity of lesions in a genetic and a nutritional form of copper deficiency in support of the view that all lesions in Menkes' disease could be ascribed to simple hypocupraemia. All lesions of Menkes' disease were shown to have their counterpart in swayback, with exception of the abnormal arborisations of the Purkinje cell dendrites. These have often been interpreted as malformations and cited in evidence of the prenatal origin of the cerebral lesions. They are, however, non-specific and similar lesions have been reported in conditions arising in later life. While there is abundant collateral evidence of disturbed copper metabolism in utero, the problem of the prenatal versus postnatal origin of cerebral damage remains unresolved.

Menkes' kinky hair disease. II. A clinicopathological report of three cases

The neuropathologic abnormalities in three new cases of Menkes' kinky hair disease are described. Principally the three cases were the same. Hypoplasia of the cerebellum, with a basal arachnoïdal cyst, was present in all three cases. The cysts were not described before in Menkes' disease. There was nerve cell loss and gliosis in the cerebral cortex, cerebellum and thalamus. The reduction of myelinated axons was widespread and the disease does not belong to the leukodystrophies. Cortical lamination disturbances were present indicating that the disease develops as early as the sixth fetal month. Abnormal arborization of Purkinje cells with swelling of dendrites was present and thought not to be identical with the Purkinje cell abnormalities seen in amaurotic idiocy. The difference in severity of the copper deficiency in 2 patients is compared with the situation in "brindled" and "blotchy" mutant mice.

Copper deficiency suppresses the immune response of mice

Mice fed a purified diet low in copper display anemia, hypoceruloplasminemia, depressed concentrations of liver copper, and elevated concentrations of liver iron. An impaired humoral-mediated immune response (decreased numbers of antibody-producing cells) is observed in mice with severe as well as marginal copper deficiency. The magnitude of this impairment is highly correlated with the degree of functional copper deficiency (hypoceruloplasminemia).

Sexual dimorphism of newborn mouse epithalamus after fractionated X-irradiation at late stage of organogenesis

Fractionated X-irradiation with 3 x 0.95, 3 x 1.05, 3 x 1.15, or 3 x 1.35 Gy on gestational days 11-13 in the mouse results in two discrete, clearly distinguishable forms of an epithalamic malformation observable on gestational day 18. Type A is characterized by a rhombic shape of the dorsal diencephalic sulcus which first narrows at the occipital edge. The habenular diameters in the plane of the habenular commissure are in the range between 81 and 88% of the control measurements. The anterior colliculi are quite well developed. The type B lesion is characterized by a rather narrow epithalamus with a sandglass-shaped dorsal diencephalic sulcus and habenular diameters that are only about 56 to 64% of the control values. With the exception of the group with the lowest radiation dose (3 x 0.95 Gy), the type B lesion predominates. The B:A ratios are 1.5 and 1.6 in the highest dosage groups, and show the most drastic increase to a ratio of 4.0 after application of 3 x 1.05 Gy. Type B lesions occur in female fetuses at a higher frequency than in males and thus shows a clear-cut correlation with the frequency and severity of neocortical lesions in the same individuals. This is again most marked in the 3 x 1.05 Gy dosage group, where the type B lesion occurs five times more frequently in females than in males. This sexual dimorphism in the reaction pattern of the epithalamus after X-irradiation in utero, can best be explained by postulating a causal link with the forebrain lesions which were recently shown to exhibit similar sexual dimorphism. We therefore postulate a retrograde transsynaptic degeneration of the thalamo-cortical fibres that develop pre-term, which is significantly expressed only after a low X-irradiation dose, but is partly abolished in the higher dosage groups. This leads to hypoplastic alterations of the epithalami, a secondary phenomenon to the neocortical lesions in the animals most affected. The resulting dysfunction of the epithalamus in the immediate neonatal period is then responsible for the preferential death of the animals with B-type lesions and also explains why female mortality is significantly higher than male mortality which occurs only in the 3 x 1.05 Gy dosage group.

Degeneration of the cerebellar system in X-chromosome-linked copper malabsorption

Examination of the cerebellar system of 5 autopsied patients with X-chromosome-linked copper malabsorption led to the discovery that among cerebellar afferent systems, only the dorsal spinocerebellar tract showed consistent degenerative changes. Cerebellar cortical lesions comprised granule cell loss and Purkinje cell abnormalities that included nuclear and cytoplasmic degenerative changes with cell loss and deficient dendritic arborization as well as the presence of somatic sprouts. Perisomatic baskets were often absent in the area of sprouting Purkinje cells. Cerebellar cortical topographical analysis revealed relative sparing of the caudal portion of the cerebellum. The nodulus was intact in all patients. The dentate nucleus and the superior cerebellar peduncle were preserved. The red nucleus was consistently degenerated.