Masayasu Minami

Interleukin-1β, interleukin-6, epidermal growth factor and transforming growth factor-α are elevated in the brain from parkinsonian patients

Interleukin (IL)-1 beta, IL-6, epidermal growth factor (EGF), and transforming growth factor-alpha (TGF-alpha) were measured for the first time in the brain (caudate nucleus, putamen and cerebral cortex) from control and parkinsonian patients by highly sensitive sandwich enzyme immunoassays. The concentrations of IL-1 beta, IL-6, EGF, and TGF-alpha in the dopaminergic, striatal regions were significantly higher in parkinsonian patients than those in controls, whereas those in the cerebral cortex did not show significant differences between parkinsonian and control subjects. Since these cytokines and growth factors may play important roles as neurotrophic factors in the brain, the present results suggest that they may be produced as compensatory responses in the nigrostriatal dopaminergic regions in Parkinsons disease, and may be related, at least in part, to the process of neurodegeneration in Parkinsons disease.

Interleukin (IL)-1β, IL-2, IL-4, IL-6 and transforming growth factor-α levels are elevated in ventricular cerebrospinal fluid in juvenile parkinsonism and Parkinson's disease ☆

Interleukin (IL)-1β, IL-2, IL-4, IL-6, epidermal growth factor (EGF), and transforming growth factor (TGF)-α were measured for the first time in ventricular cerebrospinal fluid (VCSF) from control non-parkinsonian patients, patients with juvenile parkinsonism (JP) and patients with Parkinsons disease (PD) by highly sensitive sandwich enzyme immunoassays. All cytokines were detectable in VCSF from control and parkinsonian patients, and the concentrations were much higher than those in lumbar CFS. The concentrations of IL-1β, IL-2, IL-4 and TGF-α in VCSF were higher in JP than those in controls (P < 0.05). In contrast, the concentrations of IL-2 and IL-6 in VCSF from patients with PD were higher than those from control patients (P < 0.05). These results agree with our previous reports, in which the cytokine levels were elevated in the striatal dopaminergic region of the brain from patients with PD. Since VCSF is produced in the ventricles, the alteration of cytokines in VCSF may reflect the changes of cytokines in the brain. Because cytokines play an important role as mitogens and neurotrophic factors in the brain, the increases in cytokines as a compensatory response may occur in the brain of patients of JP or PD during the progress of neurodegeneration. Increase in cytokines may contribute not only as a compensatory response but as a primary initiating trigger for the neurodegeneration.

Interleukin 1β, interleukin 6, β2-microglobulin, and transforming growth factor-α in gingival crevicular fluid from human periodontal disease

Inflammatory mediators are central to the pathogenesis of periodontal diseases and may be used as markers in diagnosis. The aim of this study was to identify and quantify the various growth factors, apoptosis-related modifiers [soluble form of Fas (sFas) and bcl-2] and cytokines in the gingival crevicular fluid (GCF) of patients with different severities of periodontitis as compared with those of controls. GCF samples were taken from patients with periodontal disease and from controls. The concentrations of epidermal growth factor, transforming growth factor (TGF)-alpha, interleukin (IL)-1 beta, IL-6, interferon-gamma, beta 2-microglobulin (beta 2-MG), and apoptosis-related modifiers sFas and bcl-2 in the samples were determined by enzyme-linked immunosorbent assay. TGF-alpha was significantly lower in patients with periodontal disease than in the controls. In contrast, the concentrations of IL-1 beta, IL-6; and beta 2-MG were significantly higher in the group with severe periodontal disease than in the controls. The amount of total protein in the GCF was considerably higher in the disease group than the controls (p < 0.05). TGF-alpha, IL-1 beta, and beta 2-MG concentrations were associated (Spearman rank correlation, r < 0.05 for all) with clinical measures of disease severity (pocket depth) and inflammation (bleeding when probed). Apoptosis-related modifiers (sFas and bcl-2) could not be detected in any samples. These results suggest that the growth factor TGF-alpha and certain cytokines are associated with the presence of periodontal disease.

Oxidation of N-Methyl-1,2,3,4-Tetrahydroisoquinoline into the N-Methyl-Isoquinolinium Ion by Monoamine Oxidase

Abstract: N‐Methyl‐1,2,3,4‐tetrahydroisoquinoline (NMTIQ) was found to be oxidized by monoamine oxidase (MAO) into N‐methylisoquinolinium ion, which was proved to inhibit enzymes related to the metabolism of catecholamines, such as tyrosine hydroxylase, aromatic‐L‐amino acid decarboxylase, and MAO. NMTIQ was oxidized by both types A and B MAO in human brain synaptosomal mitochondria. Oxidation was dependent on the amount of MAO sample and the reaction time. Enzyme activity with respect to NMTIQ reached optimum at a pH of ∼7.25, as was the case with other substrates. Type A MAO had higher activity for this substrate than type B. The Km and Vmax values of the oxidation by types A and B MAO were 571 ± 25 μM and 0.29 ± 0.06 pmol/min/mg protein, and 463 ± 43 μM and 0.16 ± 0.03 pmol/min/mg protein, respectively. The Vmax values of types A and B MAO for NMTIQ were much smaller than those for other substrates such as kynuramine. NMTIQ was the first tetrahydroisoquinoline shown to be oxidized into the isoquinolinium ion by MAO in the brain.

Method for the analysis of the methylphosphonic acid metabolites of sarin and its ethanol-substituted analogue in urine as applied to the victims of the Tokyo sarin disaster

An analysis method for the methylphosphonic acid metabolites of sarin in urine using trimethylsilyl derivatization and flame photometric detection is described in this report. Authentic reference standards of isopropyl methylphosphonic acid (IMPA) and ethyl methylphosphonic acid (EMPA) as well as methylphosphonic acid were employed to estimate the concentration in human urine. A sample pretreatment procedure was developed for urine using a column of cation-loaded ion-exchange resins (Ag+ -, Ba2+ - or H+ -Dowex) and adjusting the pH of the eluate from the column to 3.75-3.85 improved recovery of the target compounds. The eluate was evaporated to dryness under vacuum prior to trimethylsilylation, to remove water and any hydroxy- or amino-carrying volatile substances. The sarin metabolites, because of their low volatility, were concentrated and could be derivatized for analysis. The use of synthesized authentic sarin and ethylsarin metabolites, i.e., IMPA and EMPA, made it possible to establish the necessary sample pretreatment procedures for derivatization and gas chromatography-flame photometric detection (GC-FPD) analysis. The detection limits were 0.025 ppm both for EMPA and [MPA, and 0.625 microM for MPA, respectively. This method can be useful for estimating the exposure level to sarin by assaying the metabolites in urine and it is applicable to a large numbers of samples.

Organophosphorus pesticides markedly inhibit the activities of natural killer, cytotoxic T lymphocyte and lymphokine-activated killer: a proposed inhibiting mechanism via granzyme inhibition

We have previously found that diisopropyl methylphosphonate, an organophosphorus by-product generated during sarin synthesis in the Tokyo sarin disaster, significantly inhibited natural killer (NK) and cytotoxic T lymphocyte (CTL) activities. In the present study, to investigate whether organophosphorus pesticides (OPs) also affect NK and CTL activities, we firstly examined the effect of five OPs on human NK activity, and then the effect of Dimethyl 2,2-dichlorovinyl phosphate (DDVP), an OP on murine splenic NK, CTL and lymphokine-activated killer (LAK), and human LAK activities in vitro. To explore the underlying mechanism of decreased NK activity, we also investigated the effect of 4-(2-aminoethyl) benzenesulfonyl fluoride-HCl (p-ABSF), an inhibitor of serine proteases on NK, LAK and CTL activities, and the effect of DDVP on the activity of granzymes (serine proteases). We found that OPs significantly decreased human NK activity in a dose-dependent manner, but the degree of decrease in NK activity differed among the OPs investigated, and that DDVP significantly decreased NK, LAK and CTL activities in a dose-dependent manner, but the degree of decrease in these activities differed. p-ABSF showed a similar inhibitory pattern to DDVP, and had an additive inhibitory effect with DDVP on NK, LAK and CTL activities. We also found that DDVP significantly inhibited granzyme activity in a dose-dependent manner. These findings indicate that OPs significantly decrease NK, LAK and CTL activities in vitro via granzyme inhibition.

N-methylisoquinolinium ion as an inhibitor of tyrosine hydroxylase, aromatic l-amino acid decarboxylase and monoamine oxidase

The effect of the N-methylisoquinolinium ion (NMIQ(+)) on the activity of enzymes related to metabolism of dopamine was studied using a rat clonal pheochromocytoma PC12h cell line. The activities of tyrosine hydroxylase (TH), aromatic l-amino acid decarboxylase (AADC) and monoamine oxidase (MAO) were inhibited by NMIQ(+), but the mechanism of inhibition of these enzymes differed from each other. TH activity in the cells was inhibited by NMIQ(+) with an IC(50) of about 75 ?M. Aromatic l-amino acid decarboxylase (AADC) was also inhibited by NMIQ(+) but in competition with a co-factor, pyridoxal-5-phosphate, and the K(i) value was 90 ?M. MAO was inhibited by NMIQ(+) in competition with a substrate, kynuramine, and the K(i) value was 20 ?M. In vivo effects of NMIQ(+) on these enzymes in PC12h cells were examined by culture of the cells in the presence of 100 nM-1 mM NMIQ(+) for 6 days. After 6 days culture, TH activity was reduced in cells cultured with NMIQ(+) at concentrations higher than 10 ?M, but the activities of AADC and MAO were reduced only in cells cultured with 1 mM NMIQ(+). In addition, NMIQ(+) was transported into the cells by a transport system specific for dopamine. These data suggest that NMIQ(+) may perturb the catecholamine metabolism of a dopaminergic system in the brain, as a naturally-occurring compound.

The by-products generated during sarin synthesis in the Tokyo sarin disaster induced inhibition of natural killer and cytotoxic T lymphocyte activity

More than 5000 passengers on Tokyo subway trains were injured by the nerve gas, sarin and its by-products. Analysis of phosphor-carrying metabolites of sarin and its by-products in urine samples from the victims suggested that they were exposed not only to sarin, but also by-products generated during sarin synthesis, i.e. diisopropyl methylphosphonate (DIMP) and diethyl methylphosphonate (DEMP). We suspected genetic after-effects due to sarin by-products, thus, we checked the frequency of sister chromatid exchange (SCE) and found that SCE was significantly higher in the victims than in a control group, and that DIMP and DEMP significantly induced human lymphocyte SCE in vitro. In the present study, to explore whether DIMP and DEMP, which induced a high frequency of SCE of lymphocytes, also affected the lymphocyte functions, we examined the effect of DIMP and DEMP on splenic natural killer (NK) and splenic cytotoxic T lymphocyte (CTL) activity in mice, and NK activity of human lymphocytes in vitro. We found that DIMP and DEMP significantly inhibited NK and CTL activity in a dose-dependent manner. The inhibition induced by DIMP was stronger than that by DEMP. The effect of DIMP and DEMP on the splenic NK activity of mice was stronger than on the splenic CTL activity, and the human lymphocytes is more sensitive to DIMP and DEMP than the splenocytes of mice.

Acute immunotoxicity of p-chloronitrobenzene in mice : II. Effect of p-chloronitrobenzene on the immunophenotype of murine splenocytes determined by flow cytometry

To evaluate the immunotoxicity of p-chloronitrobenzene (p-CNB), we investigated its effect on the immunophenotype of murine splenocytes. BDF1 male mice were randomly divided into exposed and control groups: the exposed group received p-CNB at 300 mg/kg dissolved in olive oil, while the control group received only olive oil, by a single intraperitoneal (i.p.) or subcutaneous (s.c.) injection. On days 3, 5, 7, and 10 after the injection, splenocytes were harvested from both groups, and the following cell phenotypes were quantified by flow cytometry: (1) B cells (CD45R/B220); (2) T cells (CD3e); (3) T-cell subsets (CD4 and CD8a); (4) natural killer (NK) cells (NK-1.1); (5) macrophages (CD11b; Mac-1); (6) nucleated erythrocytes (Ter-119); and (7) dead cells with propidium iodide (PI). The percentages and numbers of B, T, subsets of T (CD4 and CD8), and NK cells in the exposed mice significantly decreased as compared with the respective control. On the other hand, macrophages (Mac-1+ cells), nucleated erythrocytes (Ter-119+ cells), and dead cells in the exposed mice markedly increased as compared with the respective control after i.p. injection of p-CNB. The above findings indicate that p-CNB has an immunotoxic effect on mice.

Acute and subchronic immunotoxicity of p-chloronitrobenzene in mice. I. Effect on natural killer, cytotoxic T-lymphocyte activities and mitogen-stimulated lymphocyte proliferation

We evaluated the immunotoxicity of p-chloronitrobenzene (p-CNB) after intraperitoneal (i.p.) injection of p-CNB in BDF1 mice; single i.p. injection of 300 mg/kg (acute experiments), or 30 mg/kg three times a week for 4 weeks (subchronic experiments). The following items were investigated: number of splenocytes, natural killer (NK) activity, cytotoxic T-lymphocyte (CTL) activity and LPS-stimulated lymphocyte proliferation using splenocytes, hemoglobin (Hb) concentration in peripheral blood and body weight. NK activity in exposed mice significantly decreased compared to control in both acute and subchronic experiments. CTL activity in acute exposed mice showed a significant decrease on the 3rd day only after injection, and significant decrease at 3 and 4 weeks in subchronic exposed mice compared to controls. Comparing the effect of p-CNB on NK activity with that of CTL for both the acute and subchronic exposures, NK activity was more inhibited by p-CNB than CTL activity in the acute stage, whereas both the NK and CTL activities were inhibited by p-CNB in the subchronic stage. There was an indication that p-CNB also inhibited LPS- stimulated B-lymphocyte proliferation. On the other hand, Hb concentration did not show significant difference between the exposed and control mice in both acute and subchronic experiments. Body weight in subchronically exposed mice was significantly lower than the control from day 19. The above evidence indicated that p-CNB has an inherent immunotoxic effect on mice.