[Three elderly cases of hyperostosis cranii with various clinical symptoms].

We report three elderly patients with hyperostosis cranii (HC). Patient 1 had two episodes of unconsciousness; patient 2, headache; and patient 3, dementia. On the basis of the classification of Moore using skull films, patients 1 and 2 showed hyperostosis frontoparietalis and patient 3 had hyperostosis frontalis interna. Electroencephalography showed transient generalized spike and slow wave complexes over the frontal lobes in patient 1. Magnetic resonance (MR) images showed frontal lobes compressed by the thickness of the frontal bones in all patients and thickened parietal bones in patients 1 and 2. Because findings in our series and in the literature suggest that HC may show unexpected neuropsychiatric symptoms, HC should be checked in elderly patients whose presenting symptoms include epilepsy, dementia, psychiatric disease, headache and so on. MR images should reveal the relationship between clinical symptoms and the deformation of brains by the skull.

Effect of methylprednisolone-pulse therapy on superoxide production of neutrophils.

Before and after treatment with methylprednisolone-pulse therapy (MPT), we investigated the superoxide production from the neutrophils of 10 patients stimulated by phorbol myristate acetate, N-formyl-methionyl-leucyl-phenylalanine or opsonized zymosan. Effects of pre-treatment with patient serum on neutrophils from control subjects were also examined. Patient neutrophils produced significantly less superoxide after MPT than before MPT. The superoxide production was significantly less in normal neutrophils from control subjects pre-treated with patient serum after MPT than in those before MPT. Neutrophils pre-treated with control serum-supplemented with or without methylprednisolone secreted essentially the same amount of superoxide. These findings indicate that MPT suppresses superoxide production by neutrophils, which is not a direct effect of methylprednisolone on neutrophils. We assume that MPT may reduce some factors from lymphocytes which stimulate not only neutrophils but also macrophages producing superoxide. This effect on the macrophages which present in the pathologic lesion may be the origin of medicinal effects of MPT.

Activated microglia cause iron-dependent lipid peroxidation in the presence of ferritin.

Ferritin contains most of the iron found in the brain, and the release of iron from ferritin has an essential role in iron-dependent lipid peroxidation. We examined the effect of cultured microglia on the ferritin-dependent lipid peroxidation of phospholipid liposomes monitored by the formation of thiobarbituric acid-reactive substances. Microglia stimulated by phorbol myristate acetate caused lipid peroxidation in the presence of ferritin. This lipid peroxidation was mediated by superoxide produced by the microglia and iron released from the ferritin. Lipid peroxidation induced by activated microglia may be partly responsible for the oxidative damage that is thought to occur in Parkinson's disease and other neurodegenerative disorders.

Serum of Behçet's disease enhances superoxide production of normal neutrophils.

Using an MCLA-dependent chemiluminescence technique, we evaluated superoxide production by neutrophils isolated from 7 patients with Behçet's disease. After stimulation by phorbol myristate acetate, N-formyl-methionyl-leucyl-phenylalanine or opsonized zymosan, neutrophils from the patients produced significantly more superoxide than those from 20 controls. Pretreatment of control neutrophils with serum prominently enhanced superoxide production, and serum from Behçet's disease patients had a significantly greater effect than that from controls. These findings suggest that serum from patients with Behçet disease contains the priming factor(s) that can enhance enhanced superoxide production by neutrophils in response to stimulation.

Activated microglia cause superoxide-mediated release of iron from ferritin.

Ferritin contains the greatest part of the iron found in the brain, and the release of iron stores from ferritin has an essential role in iron-dependent lipid peroxidation. We examined the effect of cultured microglia on iron mobilization from ferritin. Microglia stimulated by phorbol myristate acetate caused the release of iron from ferritin, which was detected by monitoring iron-ferrozine complex formation. This iron mobilization was mediated by microglial superoxide production, as evidenced by the significant inhibitory effect of superoxide dismutase. The role of superoxide was also supported by the close correspondence of cumulative microglial superoxide production, as demonstrated by the MCLA (Cypridina luciferin analogue)-dependent chemiluminescence assay, to the time course of iron release from ferritin. Iron release induced by activated microglia may be partly responsible for the oxidative damage that is thought to occur in Parkinson's disease and other neurodegenerative disorders.

Inhibitory effects of bromocriptine on phospholipid peroxidation induced by dopa and iron.

Membrane lipid peroxidation has been suggested to participate in the nigral degeneration of Parkinson's disease. In the present study, we demonstrate that bromocriptine inhibits lipid peroxidation in phospholipid liposomes induced by dopa and iron complexes. Because this lipid peroxidation is not mediated by active oxygen species, antioxidant properties of bromocriptine do not seem to be derived from radical scavenging effects in our experimental conditions. Bromocriptine had no scavenging effect on superoxide produced by hypoxanthine-xanthine oxidase when determined by the chemiluminescence assay using MCLA, a Cypridina luciferin analog, as a probe.

Inhibitory effect of bifemelane on superoxide generation by activated neutrophils measured using a simple chemiluminescence method.

We evaluated the effect of 4-(2-benzylphenoxy)-N-methylbutylamine hydrochloride (bifemelane hydrochloride) on superoxide production by human neutrophils using an MCLA-dependent chemiluminescence assay. Bifemelane hydrochloride dose-dependently inhibited superoxide production by neutrophils stimulated with phorbol myristate acetate, opsonized zymosan, or N-formyl-methionyl-leucyl-phenylalanine, while it had no effect on superoxide production by a hypoxanthine-xanthine oxidase system. These results indicate that bifemelane hydrochloride does not have a scavenging effect, but has an inhibitory effect on superoxide generation by neutrophils. Although this drug is commonly used for treating chronic cerebral infarction, it may also have a protective effect on acute ischemia/reperfusion injury.

Detection of superoxide production by activated microglia using a sensitive and specific chemiluminescence assay and microglia-mediated PC12h cell death.

Superoxide production by cultured microglia derived from neonatal rat brains and the cytotoxicity of these cells were evaluated. The chemiluminescence (photon counts) detected in the presence of MCLA, a new chemiluminescence probe, was strongly correlated with the microglial cell count. Chemiluminescence observed in this system was confirmed to originate specifically from superoxide produced by activated microglia. Phorbol myristate acetate-stimulated microglia caused a pronounced reduction of PC12h cell numbers in coculture. The addition of superoxide dismutase with catalase or the addition of deferoxamine mesylate inhibited PC12h cell death, suggesting that active oxygen species derived from superoxide generated by the microglia or iron-oxygen complex formation were responsible for the cytotoxicity. These results imply that activated microglia may participate in the progression of the pathologic process in some neurodegenerative disorders.

Synthetic melanin and ferric ions promote superoxide anion-mediated lipid peroxidation.

In this study, we demonstrate that synthetic dopa-melanin produced superoxide anions and promoted the peroxidative cleavage of phospholipids in the presence of Fe(3+)-ADP complexes. SOD significantly suppressed this lipid peroxidation, while catalase or sodium benzoate did not. During the reaction, MCLA-dependent chemiluminescence was detected, and this was suppressed to the control level by the addition of SOD. Melanin has been postulated to be toxic to tissues because of its interaction with redox-active paramagnetic metal ions, and these findings suggest that superoxide anion-mediated lipid peroxidation is induced by melanin in the presence of iron.

Glutathione cycle dependency of ferric nitrilotriacetate-induced lipid peroxidation in mouse proximal renal tubules.

Parenteral administration of ferric nitrilotriacetate (Fe-NTA), a known carcinogen in mouse and rat kidneys, enhances iron-dependent lipid peroxidation (LP) and causes acute renal tubular necrosis. We assume that filtered Fe-NTA in vivo is rapidly reduced by cysteine, a component of glutathione which is hydrolyzed by gamma-GTP and dipeptidase, and that this reduced iron initiates lipid peroxidation in the lumen. In addition, the fatty acid composition of phospholipids between the cortex and the medulla may differ, because only the proximal tubules (which are located mainly in the cortex) are known to be vulnerable to LP. We tested these assumptions in the present study. Gas chromatographic determination of fatty acid composition in five male and five female 6-week-old normal ddY mice showed the ratio of polyunsaturated fatty acids to saturated fatty acids plus C18: 1, a single double-bond fatty acid, to be 0.98 +/- 0.08 (av +/- SD) in the male cortex and 1.00 +/- 0.08 in the female cortex. In the male and female medulla, however, it was 0.78 +/- 0.09 (P < 0.05, vs cortex) and 0.68 +/- 0.04 (P < 0.01, vs cortex), respectively. Pretreatment of the animals with buthionine sulfoximine, a glutathione synthetase inhibitor, and a procedure that reduces total glutathione content in the kidneys, suppressed LP. Reduced thiobarbituric acid reactive substances were also observed in animals treated with AT-125, a gamma-GTP inhibitor, and in animals with immature gamma-GTP activity. These results are consistent with our assumptions.

Combined histochemical and biochemical demonstration of nigral vulnerability to lipid peroxidation induced by dopa and iron.

Using a newly developed lipid peroxidation-inducing system composed of DOPA and iron, we examined the vulnerability of substantia nigra to peroxidation in comparison with that of caudate-putamen obtained from normal or vitamin E-deficient animals. Histochemical detection of lipid peroxidation revealed that substantia nigra was far more susceptible than caudate putamen to DOPA and iron treatment, which was biochemically supported by measurements of thiobarbituric acid-reactive substances. Vitamin E deficiency accelerated such susceptibility of substantia nigra but had no influence on the histochemical findings observed in caudate-putamen.

Aging of the brain and vitamin E.

Using a recently-developed membrane lipid peroxidation (MLP) system, we demonstrated the important role of vitamin E in the prevention of MLP and the possible relationship between MLP and pathogenesis of Parkinson's disease.

Dopa and dopamine cause cultured neuronal death in the presence of iron.

We examined the cytotoxicity of dopa and dopamine for cultured neurons by using a newly developed enzyme immunoassay for neurofilament protein to determine surviving neuronal numbers. Each of the two catechols caused neuronal death in the presence of iron with or without superoxide dismutase and catalase, while deferoxamine mesylate prevented neuronal loss. Lipid peroxidation of phospholipid liposomes was confirmed to be produced by the combination of the catechols and iron (Fe3(+)-ADP complex). Thus, it was strongly suggested that cultured neurons were killed via the peroxidative cleavage of cell membrane components provoked by the catechols and iron. This mechanism of neuronal loss may play an important role in the degeneration in the substantia nigra of Parkinson's disease, because the catechols and iron are abundant in this region.

Phospholipid peroxidation induced by the catechol-Fe3+(Cu2+) complex: a possible mechanism of nigrostriatal cell damage.

Ferric or cupric ions significantly promoted a peroxidative cleavage of unsaturated phospholipids in liposomes in vitro after coordinating with dopa and dopamine. Either alpha-tocopherol or desferrioxamine completely abolished the dopa-Fe3+ complex-induced phospholipid peroxidation, while superoxide dismutase, catalase, or sodium benzoate did not. A ferroxidase, ceruloplasmin, significantly inhibited the lipid peroxidation induced by the dopa-Fe3+ complex, indicating the importance of the reduction of the iron moiety in the complex for the lipid peroxidation. A possible mechanism of dopa-Fe3+ complex-induced phospholipid peroxidation is that oxene complexes, such as Fe(V) = O and Fe(IV) = O, produced abstract hydrogen atoms in unsaturated phospholipids to initiate lipid peroxidation.

[Systemic lupus erythematosus presenting chronic relapsing polyneuropathy as the first manifestation without auto-antibodies].

Chronic relapsing polyneuropathy (CRPN) is an idiopathic disorder characterized by relapsing and remitting course, elevated CSF protein, slow nerve conduction and absence of systemic disease(s). Systemic lupus erythematosus (SLE), however, has been reported to manifest clinical symptoms and signs mimicking CRPN. A few authors described CRPN as a presenting manifestation or more rarely as the only illness of SLE. In these cases diagnosis of SLE was confirmed by some laboratory tests to detect auto-antibodies which were positive in subclinical SLE. We experienced a 24-year-old female whose illness started as CRPN without any auto-antibodies and recurred with autoimmune abnormalities indicating SLE. She noticed muscle weakness in the lower extremities about ten months previous to the first admission. The weakness progressed gradually and was accompanied by urinary incontinence and sensory deficits in limbs. In another hospital lumbar puncture revealed highly elevated CSF protein and she was referred to us. Neurologic examination showed sensorimotor polyneuropathy with normal blood chemistry and negative auto-antibodies. Prednisolone therapy brought out gradual improvement. She was readmitted 2 years after the first admission because of severe motor dominant polyneuropathy. Serological examination revealed positive auto-antibodies including antinuclear (ANA), anti-DNA, anti-RNP and anti-ENA antibodies. CBC showed decreased number of white blood cells. Nerve conduction velocities were markedly reduced. Again prednisolone was administrated successfully. Thereafter, she experienced several relapsing and remitting cycles. It was characteristic that deterioration of symptomatological findings such as motor weakness was always accompanied by an elevated titer of ANA and increased CSF protein in each of the cycles.(ABSTRACT TRUNCATED AT 250 WORDS)

[Iron-dependent cytotoxic effects of dopa on cultured neurons of the dorsal root ganglia].

Although many authors have suggested that dopamine and its metabolites producing free radicals have an harmful effect in the substantia nigra, experimental evidence has not been shown. Using a newly established enzyme immunoassay of the neurofilament protein, a reliable index for the number of survived neurons in tissue culture, we evaluate the effects of Dopa on the neurons of dorsal root ganglia from mice. Neurons were destroyed by the exposure of 0.5 mM Dopa with or without superoxide dismutase and catalase, but they were saved by the pretreatment with 1.0 mM deferoxamine mesylate, a powerful iron-chelating agent. Formation of malondialdehyde, an index of lipid peroxidation, was also observed in the reaction of 0.5 mM Dopa and cerebral cortical neurons from new-born rats only when iron was present. These results indicate that Dopa initiates lipid peroxidation of cell membrane in the presence of a small amount of iron in the culture with little or no participation of reactive oxygen species, leading to the destruction of the neurons. In Parkinson's disease, the cytotoxic mechanism of Dopa and iron may involve the neuronal degeneration in the substantia nigra abundant in iron and dopaminergic neurons.

[Free radicals and degenerative diseases of the nervous system].

Degenerative diseases of the nervous system which are considered to be related to free radicals are Parkinson's disease and Alzheimer-type dementia (ATD). Parkinson's disease is characterized by appearance of Leyw's body and degeneration of nigrostriatal dopaminergic system. But the most fundamental cause of this disease remains still unknown. The fact that H2O2 is formed in the process of oxidative deamination of catecholamines and some substances which can cause Parkinsonism in animal experiments also produce active oxygen in the metabolic processes suggest the important role of free radicals in the pathogenesis of Parkinson's disease. We recently observed that addition of DOPA and Fe3(+)-ADP complex to the microsomal phospholipid system produced lipid peroxides without participation of active oxygen. Neurons cultured in vitro also decreased significantly with addition of DOPA and Fe3(+)-ADP complex and this harmful effect was prevented by desferoxamine (potent Fe chelating agent) or alpha-tocopherol (antioxidant). These results may suggest that lipid peroxidation can occur by interaction of naturally existing substances in the dopaminergic system and induce cell damage. As regards ATD, there is still no definite evidence to support the implication of free radicals in its pathogenesis. However, there are reports that lipid peroxides increase significantly in the brains of patients with ATD. Moreover, recent advances in the study of amyloid in the senile plaque revealed close relationship of ATD to chromosome 21.(ABSTRACT TRUNCATED AT 250 WORDS)

Antioxidant activity of probucol. Short communication.

To evaluate a possible antioxidant activity of probucol on NADPH-dependent microsomal lipid peroxidation and on iron-doxorubicin (adriamycin) complex-induced phospholipid peroxidation, the effects were compared with another powerful antioxidant, 2-OH-estrone. Antioxidant activity of 10 mumol/l probucol in NADPH-dependent microsomal lipid peroxidation corresponded to 4 mumol/l 2-OH-estrone. Together with the results obtained from iron-doxorubicin complex-induced phospholipid peroxidation, it was concluded that probucol is a potent inhibitor of lipid peroxidation and has one-quarter to one-half the antioxidant activity of 2-OH-estrone in vitro.

A new and suitable reconstructed system for NADPH-dependent microsomal lipid peroxidation.

In order to evaluate the O-2 participation in NADPH-dependent microsomal lipid peroxidation, we used reconstructed system which contained detergent-solubilized NADPH-dependent cytochrome P-450 reductase, cytochrome P-450, phospholipid liposomes, NADPH and Fe3+-ADP. Lipid peroxidation, monitored by the formation of thiobarbituric acid-reactive substance, was increased with increasing concentration of detergent-solubilized NADPH cytochrome P-450 reductase, cytochrome P-450 or Fe3+-ADP. Cytochrome P-450-dependent lipid peroxidation was parallel to O-2 generation monitored by chemiluminescence probe with 2-methyl-6-(p-methoxyphenol)-3,7-dihydroimidazo[1,2-a]pyrazin++ +-3-one. Lipid peroxidation was significantly inhibited by superoxide dismutase, but not by catalase or sodium benzoate. The reconstructed system herein described is considered to be very close to NADPH-dependent microsomal lipid peroxidation system.