Signal transducer and activator of transcription-3 (STAT3) is a member of the proinflammatory transcription factor STAT family. Several studies have documented implications for neuroinflammation in amyotrophic lateral sclerosis (ALS). We recently demonstrated activation of STAT3 in spinal cords obtained at autopsy from sporadic ALS patients. To determine the involvement of STAT3 and effects of pioglitazone on STAT3 activity in familial ALS with superoxide dismutase-1 (SOD1) mutation, we performed immunoblot and immunohistochemical analyses of the active form of STAT3 (p-STAT3) in spinal cords from mice overexpressing mutant SOD1 (ALS mice) and nontransgenic littermates (control mice). Immunoblot analysis delineated significant increases in nuclear p-STAT3 levels in non-treated ALS mice as compared with pioglitazone-treated ALS mice and non-treated and pioglitazone-treated control mice. Immunohistochemical analysis revealed prominent p-STAT3 accumulations in the nucleus of motor neurons, reactive astrocytes and activated microglia in non-treated ALS mice but not pioglitazone-treated ALS mice and non-treated and pioglitazone-treated control mice. The present results provide in vivo evidence for increased phosphorylative activation and nuclear translocation of STAT3 in motor neurons and glia in mouse motor neuron disease, suggesting a common pathological process between sporadic and SOD1-mutated familial forms of ALS. Moreover, it is likely that pioglitazone may exert inhibitory effects on STAT3-mediated proinflammtory mechanisms in this disease.

Fukutin is a gene responsible for Fukuyama-type congenital muscular dystrophy (FCMD), accompanying ocular and brain malformations represented by cobblestone lissencephaly. Fukutin is related to basement membrane formation via the glycosylation of α-dystoglycan (α-DG), and astrocytes play a crucial role in the pathogenesis of the brain lesion. On the other hand, its precise function in neurons is unknown. In this experiment, the roles of fukutin in mature and immature neurons were examined using brains from control subjects and FCMD patients and cultured neuronal cell lines. In quantitative PCR, the expression level of fukutin looked different depending on the region of the brain examined. A similar tendency in DG expression appears to indicate a relation between fukutin and α-DG in mature neurons. An increase of DG mRNA and core α-DG in the FCMD cerebrum also supports the relation. In immunohistochemistry, dot-like positive reactions for VIA4-1, one of the antibodies detecting the glycosylated α-DG, in Purkinje cells suggest that fukutin is related to at least a post-synaptic function via the glycosylation of α-DG. As for immature neurons, VIA4-1 was predominantly positive in cells before and during migration with expression of fukutin, which suggest a participation of fukutin in neuronal migration via the glycosylation of α-DG. Moreover, fukutin may prevent neuronal differentiation, because its expression was significantly lower in the adult cerebrum and in differentiated cultured cells. A knockdown of fukutin was considered to induce differentiation in cultured cells. Fukutin seems to be necessary to keep migrating neurons immature during migration, and also to support migration via α-DG.

Recent studies have suggested implications for α-synuclein cytotoxicity in the pathomechanism of multiple system atrophy (MSA). Given in vitro evidence that α-synuclein generates oxidative stress, it is proposed that lipid peroxidation may be accelerated in MSA. To address this issue, we performed an immunohistochemical analysis of protein-bound 4-hydroxy-2-nonenal (P-HNE) in sections of archival, formalin-fixed, paraffin-embedded pontine materials of eight sporadic MSA patients and eight age-matched control subjects. In the MSA cases, P-HNE immunoreactivity was localized in all of the neuronal cytoplasmic inclusions and glial cytoplasmic inclusions, both of them identified with α-synuclein and ubiquitin. It was also detectable in reactive astrocytes and phagocytic microglia but undetectable in activated microglia. By contrast, P-HNE immunoreactivity in the control cases was only very weak or not at all in the parenchyma including neurons and glia. The present results provide in vivo evidence that HNE participates in α-synuclein-induced cytotoxicity and neuroinflammation in MSA.

Several studies have suggested the involvement of neuroinflammation in the pathomechanism of neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS). We recently demonstrated increased levels of protein-bound 4-hydroxy-2-nonenal (HNE) as a highly reactive lipid peroxidation product and cytosolic phospholipase A(2) (cPLA(2)) as a proinflammatory enzyme in glial cells as well as motor neurons in the spinal cord of sporadic ALS patients. However, a link between HNE and cPLA(2) in ALS remains to be determined. To address this issue, we investigated effects of HNE stimulation on the state of cPLA(2) expression in cultured microglial cell line (Ra2). Exposure of Ra2 cells to HNE significantly increased expression levels of cPLA(2) and its activated form phosphorylated at amino acid residue S(505) (p-cPLA(2)) on immunoblots. Pretreatment of Ra2 cells with the antioxidant N-acetylcysteine, the extracellular signal-regulated kinase (ERK) inhibitor PD98059 or the p38 mitogen-activated protein kinase (MAPK) inhibitor SB203580 prevented the HNE-induced increased expression of cPLA(2) and p-cPLA(2). Immunocytochemical analysis revealed that staining for p-cPLA(2) in Ra2 cells was localized in the cytoplasm and more intense in the HNE-stimulated group than in the vehicle group. The present results provide in vitro evidence that HNE upregulates and phosphorylates cPLA(2) in microglia via the ERK and p38 MAPK pathways.

Adenoid cystic carcinoma (ACC) is a malignant neoplasm that commonly arises in the major or minor salivary gland and usually forms mass lesions. Here, we report a case of ACC involving a 56-year-old man, who displayed right multiple cranial nerve palsies with ipsilateral severe facial pain but not any mass formation. Right submaxillary gland biopsy after repeated challenges at last revealed the primary focus of ACC with perineural invasion and without lymph node metastasis. The neurological manifestations were considered to be attributed to the perineural spread of ACC. It is extremely rare for ACC to show Garcin's syndrome without mass formation.