Immunohistochemical and ultrastructural evidence for the pathogenesis of white matter degeneration in patients with panencephalopathic-type Creutzfeldt-Jakob disease: Inducible nitric oxide synthase overexpression in bizarre astrocytes.

Excessive production of nitric oxide (NO) due to the overinduction of inducible nitric oxide synthase (iNOS) has a severe cytotoxic effect, which may relate to the pathogenesis of neurodegenerative disorders. In this study, we report the novel finding that iNOS is overinduced in a large number of bizarre astrocytes in the white matter of patients with panencephalopathic (PE)-type Creutzfeldt-Jakob disease (CJD). This study was carried out on brain tissue from seven patients with PE-type CJD. As controls, 12 normal individuals and nine patients with cerebral infarction were examined. We identified a large number of bizarre astrocytes in the degenerative cerebral white matter in PE-type CJD. Using immunohistochemistry, only bizarre astrocytes in PE-type CJD showed strong immunoreactivity for both iNOS and superoxide dismutase 1 (SOD1). Ultrastructural examination demonstrated that these bizarre astrocytes contained many free polyribosome-like granules. No significant iNOS immunoreactivity was observed in either the astrocytes of patients with cerebral infarcts or in the normal controls. This study suggests that the iNOS-overexpressing astrocytes, especially iNOS-overexpressing bizarre astrocytes, could play an important role in the development of white matter lesions in PE-type CJD. Our data also suggest that the bizarre astrocytes could be protecting themselves from the cytotoxicity of NO by producing SOD1. These immunohistochemical findings are supported by the ultrastructural observation of numerous polyribosome granules restricted to the cytoplasm of these bizarre astrocytes.

Ultrastructure of spinal anterior horn cells in human Niemann-Pick type C (NPC) patient and mouse model of NPC with retroposon insertion in NPC1 genes.

Niemann-Pick disease type C (NPC) is a neurovisceral lipid-storage disease. Although NPC patients show lipid storage in anterior horn cells of the spinal cord, little information is available regarding the electron microscopic analyses of the morphologies of intra-endosomal lipid like-materials in the anterior horn cells of NPC patients. In this study, we elucidated the intra-endosomal ultrastructures in spinal anterior horn cells in an NPC patient, as well as in mutant BALB/c NPC1-/- mice with a retroposon insertion in the NPC1 gene. These morphologies were classified into four types: vesicle, multiple concentric sphere (MCS), membrane, and rose flower. The percentages of the composition in the NPC patient and NPC1-/- mice were: vesicle (55.5% and 14.9%), MCS (15.7% and 3.4%), membrane (23.6% and 57.1%), and rose flower (5.2% and 24.6%), respectively. Formation of the intra-endosomal structures could proceed as follows: (i) a vesicle or MCS buds off the endosome into the lumen; (ii) when a vesicle breaks down, a membrane is formed; and (iii) after an MCS breaks down, a rose flower structure is formed. Our new finding in this study is that ultrastructural morphology is the same between the NPC patient and NPC1-/- mice, although there are differences in the composition.

Orengedokuto and san'oshashinto improve memory deficits by inhibiting aging-dependent activation of glycogen synthase kinase-3ß.

BACKGROUND AND AIM: The aging-dependent activation of glycogen synthase kinase-3ß (GSK-3ß) has been suggested to be important in the onset of dementia. To discover novel therapeutic Kampo medicines for dementia, we examined the effects of orengedokuto (OGT; huáng lián jiedú tang) and san'oshashinto (SST; san huáng xiè xin tang) on memory deficits and GSK-3ß activity in senescence-accelerated prone mice (SAMP8). EXPERIMENTAL PROCEDURE: The object recognition test (ORT) and conditioned fear memory test (CFT) were employed to elucidate short-term working memory and long-term fear memory. The activity of GSK-3ß and the phosphorylation of related molecules were measured using a kinase assay and Western blotting. RESULTS AND CONCLUSION: OGT and SST attenuated memory deficits in SAMP8 in ORT, but not in CFT. In ex vivo experiments, cortical GSK-3ß activity was significantly stronger in SAMP8 than in SAMR1. The enhanced cortical GSK-3ß activity in SAMP8 was accompanied by a significant increase in the level of phosphorylated collapsin response mediator protein-2 (CRMP2), an important factor that is involved in the regulation of microtubule stability. OGT and SST attenuated not only increases in cortical GSK-3ß activity, but also the levels of phosphorylated CRMP2 in SAMP8. In vitro experiments, flavonoids contained in these kampo medicines, inhibited GSK-3ß activity in concentration-dependent manners. These results suggest that OGT and SST prevent aging-induced short-term working memory deficits by inhibiting aging-dependent elevations in the cortical GSK-3ß activity and subsequent CRMP2 phosphorylation.