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The development of new and mild protocols for the specific enrichment of biomolecules is of significant interest from the perspective of chemical biology. A cobalt-phosphine complex immobilised on a solid-phase resin has been found to selectively bind to a propargyl carbamate tag, that is, "catch", under dilute aqueous conditions (pH 7) at 4 °C. Upon acidic treatment of the resulting resin-bound alkyne-cobalt complex, the Nicholas reaction was induced to "release" the alkyne-tagged molecule from the resin as a free amine. Model studies revealed that selective enrichment of the alkyne-tagged molecule could be achieved with high efficiency at 4 °C. The proof-of-concept was applied to an alkyne-tagged amino acid and dipeptide. Studies using an alkyne-tagged dipeptide proved that this protocol is compatible with various amino acids bearing a range of functionalities in the side-chain. In addition, selective enrichment and detection of an amine derived from the "catch and release" of an alkyne-tagged dipeptide in the presence of various peptides has been accomplished under highly dilute conditions, as determined by mass spectrometry., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In the rodent brain, certain G protein-coupled receptors and adenylyl cyclase type 3 are known to localize to the neuronal primary cilium, a primitive sensory organelle protruding singly from almost all neurons. A recent chemical screening study demonstrated that many compounds targeting dopamine receptors regulate the assembly of Chlamydomonas reinhardtii flagella, structures which are analogous to vertebrate cilia. Here we investigated the effects of dopaminergic inputs loss on the architecture of neuronal primary cilia in the rodent striatum, a brain region that receives major dopaminergic projections from the midbrain. We first analyzed the lengths of neuronal cilia in the dorsolateral striatum of hemi-parkinsonian rats with unilateral lesions of the nigrostriatal dopamine pathway. In these rats, the striatal neuronal cilia were significantly longer on the lesioned side than on the non-lesioned side. In mice, the repeated injection of reserpine, a dopamine-depleting agent, elongated neuronal cilia in the striatum. The combined administration of agonists for dopamine receptor type 2 (D2) with reserpine attenuated the elongation of striatal neuronal cilia. Repeated treatment with an antagonist of D2, but not of dopamine receptor type 1 (D1), elongated the striatal neuronal cilia. In addition, D2-null mice displayed longer neuronal cilia in the striatum compared to wild-type controls. Reserpine treatment elongated the striatal neuronal cilia in D1-null mice but not in D2-null mice. Repeated treatment with a D2 agonist suppressed the elongation of striatal neuronal cilia on the lesioned side of hemi-parkinsonian rats. These results suggest that the elongation of striatal neuronal cilia following the lack of dopaminergic inputs is attributable to the absence of dopaminergic transmission via D2 receptors. Our results provide the first evidence that the length of neuronal cilia can be modified by the lack of a neurotransmitter's input.

The dopamine reuptake inhibitor bupropion and dopamine D2/3 receptor agonist pramipexole have been clinically proven to improve both depression and treatment-resistant depression. We examined its influence on the duration of immobility during the forced swim test in adrenocorticotropic hormone (ACTH)-treated rats and further analyzed the possible role of the dopamine nerve system in this effect. Bupropion and pramipexole significantly decreased the duration of immobility in normal and ACTH-treated rats. We previously demonstrated that the chronic administration of ACTH caused a significant decrease in hippocampal cell proliferation and neurogenesis. In this study, we used the mitotic marker 5-bromo-2'-deoxyridine to investigate the effects of bupropion and pramipexole on cell proliferation in the subgranular zone of the hippocampal dentate gyrus following chronic treatment with ACTH. The ACTH treatment for 14 d decreased adult hippocampal cell proliferation. The chronic administration of bupropion for 14 d blocked the loss of cell proliferation resulting from the chronic treatment with ACTH, whereas pramipexole did not. The administration of bupropion may have treatment-resistant antidepressive properties, which may be partly attributed to the normalization of hippocampal cell proliferation.

The specific toxicity to dopaminergic neurons of psychostimulants and neurotoxins has been extensively studied in vivo and in vitro, and findings have been used to establish animal models of amphetamine psychosis or Parkinson's disease. The multiple mechanisms of neurotoxicity operating in these disorders are known to involve oxidative stress or neuroinflammation, producing the characteristic behavioral and neuropathlogical changes arising from injured dopaminergic neurons and glial cells. A number of studies have shown that glia-targeting antioxidants play important roles in protecting against the neurotoxicity caused by psychostimulants or neurotoxins. Phytochemicals, which are non-nutritive plant chemicals, protect dopaminergic neurons and glial cells from damage caused by psychostimulants or neurotoxins. The objective of this review was to evaluate the involvement of glial cells in dopaminergic neuron-specific toxicity and to explore the neuroprotective activity of phytochemicals in terms of anti-inflammatory and antioxidant action.

Oxidative stress and inflammation play important roles in diabetic complications, including diabetic nephropathy. Metallothionein (MT) is induced in proximal tubular epithelial cells as an antioxidant in the diabetic kidney; however, the role of MT in renal function remains unclear. We therefore investigated whether MT deficiency accelerates diabetic nephropathy through oxidative stress and inflammation. Diabetes was induced by streptozotocin injection in MT-deficient (MT(-/-)) and MT(+/+) mice. Urinary albumin excretion, histological changes, markers for reactive oxygen species (ROS), and kidney inflammation were measured. Murine proximal tubular epithelial (mProx24) cells were used to further elucidate the role of MT under high-glucose conditions. Parameters of diabetic nephropathy and markers of ROS and inflammation were accelerated in diabetic MT(-/-) mice compared with diabetic MT(+/+) mice, despite equivalent levels of hyperglycemia. MT deficiency accelerated interstitial fibrosis and macrophage infiltration into the interstitium in the diabetic kidney. Electron microscopy revealed abnormal mitochondrial morphology in proximal tubular epithelial cells in diabetic MT(-/-) mice. In vitro studies demonstrated that knockdown of MT by small interfering RNA enhanced mitochondrial ROS generation and inflammation-related gene expression in mProx24 cells cultured under high-glucose conditions. The results of this study suggest that MT may play a key role in protecting the kidney against high glucose-induced ROS and subsequent inflammation in diabetic nephropathy.

Astrocytes are abundant neuron-supporting glial cells that harbor a powerful arsenal of neuroprotective antioxidative molecules and neurotrophic factors. Here we examined whether enrichment with healthy striatal astrocytes can provide neuroprotection against progressive dopaminergic neurodegeneration. Serotonin 1A (5-HT1A) agonist 8-OH-DPAT induced astrocyte proliferation and increased metallothionein-1/-2 (MT-1/-2), antioxidative molecules, in cultured astrocytes and the striatum of mice. Primary cultured mesencephalic dopamine neurons were protected against oxidative stress by preincubation with conditioned media from 8-OH-DPAT-treated astrocytes. These protective effects were canceled by 5-HT1A antagonist or MT-1/-2-specific antibody. Furthermore, reduction of nigrostriatal dopaminergic neurons in 6-hydroxydopamine-lesioned parkinsonian model mice was significantly abrogated by repeated injections of 8-OH-DPAT. Treatment with 8-OH-DPAT markedly increased the expression of MT in striatal astrocytes in the hemi-parkinsonian mice. Our study provides a promising therapeutic strategy of neuroprotection against oxidative stress and progressive dopaminergic neurodegeneration by demonstrating the efficacy of targeting 5-HT1A receptors in astrocytes., (© 2013.)

Purpose: To investigate the feasibility of dual-energy subtraction (DES) in patients with moderate-severe cervical spondylosis for improving delineation of the larynx on flat panel detector (FPD) radiography., Materials and Methods: For 118 patients, we graded conventional/DES anterior-posterior views for delineation of the vocal cords, subglottis, and pyriform sinus using a 5-point scale and lateral views from conventional laryngeal FPD radiography to determine cervical spondylosis severity on a scale from 0 (none) to 3 (severe). We compared the delineation of each anatomical structure in both groups of grades 0-1 and grades 2-3 of spondylosis severity between conventional and DES methods and the improved delineation rate for each anatomical structure by DES compared to the conventional method between both groups., Results: With DES, the delineation of each anatomical structure was significantly better than with conventional radiography for both groups (P < 0.0001). The improved delineation rate of the vocal cord and subglottis using DES was significantly higher in grades 2-3 than in grades 0-1 (P < 0.05), although there was no significant difference in the delineation rate of the pyriform sinus between the groups (P = 0.847)., Conclusion: DES provides better delineation of the laryngeal anatomy than conventional FPD radiography predominantly in patients with moderate-severe cervical spondylosis.

Tyrosinase, which catalyzes both the hydroxylation of tyrosine and consequent oxidation of L-DOPA to form melanin in melanocytes, is also expressed in the brain, and oxidizes L-DOPA and dopamine. Replacement of dopamine synthesis by tyrosinase was reported in tyrosine hydroxylase null mice. To examine the potential benefits of autograft cell transplantation for patients with Parkinson's disease, tyrosinase-producing cells including melanocytes, were transplanted into the striatum of hemi-parkinsonian model rats or mice lesioned with 6-hydroxydopamine. Marked improvement in apomorphine-induced rotation was noted at day 40 after intrastriatal melanoma cell transplantation. Transplantation of tyrosinase cDNA-transfected hepatoma cells, which constitutively produce L-DOPA, resulted in marked amelioration of the asymmetric apomorphine-induced rotation in hemi-parkinsonian mice and the effect was present up to 2 months. Moreover, parkinsonian mice transplanted with melanocytes from the back skin of black newborn mice, but not from albino mice, showed marked improvement in the apomorphine-induced rotation behavior up to 3 months after the transplantation. Dopamine-positive signals were seen around the surviving transplants in these experiments. Taken together with previous studies showing dopamine synthesis and metabolism by tyrosinase, these results highlight therapeutic potential of intrastriatal autograft cell transplantation of melanocytes in patients with Parkinson's disease.

RE derivatives, which are cell-permeable and non-electrophilic dual-specificity protein phosphatase inhibitors developed in our laboratory, inhibit CDC25A/B non-competitively, as determined by means of kinetic experiments. To identify the binding site of RE derivatives, we designed and synthesized the new probe molecule RE142, having a Michael acceptor functionality for covalent bond formation with the enzyme, a biotin tag to enable enrichment of probe-bound peptide(s), and a chemically cleavable linker to facilitate release of probe-bound peptides from avidin beads. LC-MS analysis indicated that RE142 binds to one of the residues Cys384-Tyr386 of CDC25A, within a pocket adjacent to the catalytic site.

Aims: Cisplatin (CDDP) is a potent anticancer agent, but severe renal toxicity can limit its use. We investigated the protective effect of cepharanthin (CE), a biscoclaurin alkaloid, on the renal toxicity of CDDP., Main Methods: Mice were given CDDP along with CE. Effects of CE on CDDP toxicity were investigated by assaying markers of renal toxicity together with MT expression, and by histopathological examination of the kidney. MT-null mice were also examined., Key Findings: CE induced expression of metallothionein (MT). Pre-administration of CE attenuated an increase in blood urea nitrogen (BUN) concentrations after the CDDP injection. A histochemical analysis demonstrated protection against CDDP-induced necrocytosis of kidney tissues by CE. The protective effect of CE did not occur in the MT-null mice., Significance: Pretreatment with CE may reduce the renal toxicity of CDDP through expression of MT., (Copyright © 2013 Elsevier Inc. All rights reserved.)

In clinical studies, electroconvulsive stimuli have been associated with improvements in both depression and treatment-resistant depression. In a previous study, treatment with adrenocorticotropic hormone (ACTH) for 14 days decreased adult hippocampal cell proliferation. Furthermore, electroconvulsive stimuli significantly decreased the duration of immobility following repeated administration of ACTH for 14 days in rats. The present study was undertaken to further characterize the mechanism of treatmentresistant antidepressant effects of electroconvulsive stimuli by measuring cell proliferation, brain-derived neurotrophic factor (BDNF) levels, and phosphorylated and total cyclic adenosine monophosphate (cAMP) response element-binding protein (pCREB/CREB) levels in the hippocampus of ACTH-treated rats. Electroconvulsive stimuli increased cell proliferation in both saline-treated and ACTH-treated rats. Mature-BDNF protein levels showed a tendency to decrease in ACTH-treated rats. Electroconvulsive stimuli treatment increased mature-BDNF protein levels in the hippocampus of both saline-treated and ACTH-treated rats. Furthermore, electroconvulsive stimuli increased phospho-Ser133-CREB (pCREB) levels and the ratio of pCREB/CREB in both saline-treated and ACTH-treated rats. These findings suggest that the treatment-resistant antidepressant effects of electroconvulsive stimuli may be attributed, at least in part, to an enhancement of hippocampal cell proliferation.

The gas chromatography-flame ionization detector equipped with a higher polarity column (i.e., SP-2560) has often been used for the quantification of trans-fatty acids in food. In particular, AOCS Ce 1h-05, the official method of the American Oil Chemists' Society (AOCS), is a highly effective method to separate the isomers of trans-fatty acids. In this study, the resolution behavior and the response factors of cis- and trans-octadecenoic acid methyl ester (C18:1-ME) isomers separated by the AOCS Ce 1h-05 method were investigated, and the contents of each cis- and trans-C18:1-ME isomer in partially hydrogenated vegetable oil (PHVO) and milk fat were quantified by using the calibration curves obtained for the respective isomers. The relative response factors for the trans- and cis-C18:1-ME isomers against the internal standard heneicosanoic acid methyl ester (C21:0-ME) were 1.031 ± 0.040 (mean ± SD) and 0.990 ± 0.032, respectively. The relative response factors of trans-isomers tend to be higher than those of cis-C18:1-ME isomers. The peaks of cis-4-C18:1-ME, cis-5-C18:1-ME, cis-6-C18:1-ME, cis-7-C18:1-ME, cis-8-C18:1-ME, and cis-9-C18:1-ME isomers overlapped with those of trans-C18:1-ME isomers. Both PHVO and milk fat contained many types of cis- and trans-C18:1 isomers, and the total contents of the trans-C18:1 isomer in PHVO and milk fat were 28.01 g and 3.62 g per 100 g oil, respectively. When the trans-C18:1-ME isomer was separated from the cis-C18:1-ME by using a silver-ion cartridge column before the analyses, the total contents of the trans-C18:1 isomer in PHVO and milk fat were 23.03 g and 2.78 g per 100 g oil, respectively. The difference in the trans-C18:1 isomer content between the two methods was ascribed to the partial overlapping of cis-isomer peaks with the peaks of trans-C18:1-ME isomers, in the chromatogram.

Lewy bodies containing the centrosomal protein γ-tubulin and fragmentation of Golgi apparatus (GA) have been described in nigral neurons of Parkinson's disease (PD) patients. However, the relevance of these features in PD pathophysiology remains unknown. We analyzed the impact of proteasome inhibition in the formation of γ-tubulin-containing aggregates as well as on GA structure. SH-SY5Y cells were treated with the proteasome inhibitor Z-Leu-Leu-Leu-al (MG132) to induce centrosomal-protein aggregates. Then, microtubules (MTs) and Golgi dynamics, as well as the vesicular transport of dopamine transporter (DAT) were evaluated both in vitro and in living cells. MG132 treatment induced γ-tubulin aggregates which altered microtubule nucleation. MG132-treated cells containing γ-tubulin aggregates showed fragmentation of GA and perturbation of the trans-Golgi network. Under these conditions, the DAT accumulated at the centrosomal-Golgi region indicating that the vesicular transport of DAT was disrupted. Thus, centrosomal aggregates and fragmentation of GA are 2 closely related processes that could result in the disruption of the vesicular transport of DAT toward the plasma membrane in a model of dopaminergic neuronal degeneration., (Copyright © 2012 Elsevier Inc. All rights reserved.)

A 23-year-old man presented with a mass in the pineal region and obstructive hydrocephalus. A neuroendoscopicbiopsy for the lesion, ventriculoperitoneal (VP)shunting, and focal irradiation were conducted as initial treatment. Histological diagnosis of the biopsy specimen was germinoma. He underwent further irradiation and two tumor resections. Histological diagnosis was mature teratoma without a germinomatous component. After serial treatments, the intracranial lesion was controlled. However,14 months after presentation, extraneural lesions were confirmed in the posterior mediastinum and retroperitoneal space. The biopsy specimen of the retroperitoneal space lesion was histologically diagnosed as germinoma. Although chemotherapy with cisplatin and etoposide was undertaken,extraneural lesions ware uncontrollable and he died. At autopsy, extraneural lesions were confirmed in the posterior mediastinum, retroperitoneal space, and right lung. Histological diagnosis of extraneural lesions was germinoma.This case was considered to be a pineal mixed germ cell tumor mainly consisting of germinoma and mature teratoma,which caused hematogenous metastasis of the germinoma component. Systemic chemotherapy and irradiation for primary lesions as an initial treatment is important to cure the primary lesion and prevent extraneural metastasis.

Prostaglandin H synthase exerts not only cyclooxygenase activity but also peroxidase activity. The latter activity of the enzyme is thought to couple with oxidation of dopamine to dopamine quinone. Therefore, it has been proposed that cyclooxygenase inhibitors could suppress dopamine quinone formation. In the present study, we examined effects of various cyclooxygenase inhibitors against excess methyl L-3,4-dihydroxyphenylalanine (L-DOPA)-induced quinoprotein (protein-bound quinone) formation and neurotoxicity using dopaminergic CATH.a cells. The treatment with aspirin inhibited excess methyl L-DOPA-induced quinoprotein formation and cell death. However, acetaminophen did not show protective effects, and indomethacin and meloxicam rather aggravated these methyl L-DOPA-induced changes. Aspirin and indomethacin did not affect the level of glutathione that exerts quenching dopamine quinone in dopaminergic cells. In contrast with inhibiting effects of higher dose in the previous reports, relatively lower dose of aspirin that affected methyl L-DOPA-induced quinoprotein formation and cell death failed to prevent cyclooxygenase-induced dopamine chrome generation in cell-free system. Furthermore, aspirin but not acetaminophen or meloxicam showed direct dopamine quinone-scavenging effects in dopamine-semiquinone generating systems. The present results suggest that cyclooxygenase shows little contribution to dopamine oxidation in dopaminergic cells and that protective effects of aspirin against methyl L-DOPA-induced dopamine quinone neurotoxicity are based on its cyclooxygenase-independent property.

Objectives and Methods: We have searched for low-molecular-weight compounds as potent new non-immunosuppressive immunophilin ligands (NI-IPLs) that are stronger than existent NI-IPLs such as GPI1046 and/or V10367 from the perspective of neuroprotective efficacy. We selected six dipeptidyl compounds as new NI-IPL candidates, and first examined the effects of each of these compounds on the serum-deprivation-induced reduction in the viability of SH-SY5Y cells. In addition, we clarified the effects of these compounds on neurotrophin release into medium in SH-SY5Y cells., Results: Pre-treatment with Leu-Ile and Ile-Ile prevented the serum deprivation-induced reduction in cell viability in SH-SY5Y cells. In naive SH-SY5Y cells, treatment with Leu-Ile and Ile-Ile for 24 hours significantly increased both brain-derived neurotrophic factor and glial cell-line-derived neurotrophic factor releases in comparison with relative vehicle treatments. Moreover, none of the dipeptidyl compounds could prevent the concanavalin A-induced enhancement in interleukin-2 and interleukin-4 release in mouse spleen cells., Discussion: The immunosuppressive effect is not essential to the neuroprotective properties of dipeptidyl compounds, and Leu-Ile and Ile-Ile have neurotrophin-activating effects, like FK506 and its existing non-immunosuppressive derivatives.

Objective: Residual renal function (RRF) is associated with low oxidative stress in peritoneal dialysis (PD). In the present study, we investigated the relationship between the impact of oxidative stress on RRF and patient outcomes during PD., Methods: Levels of free radicals (FRs) in effluent from the overnight dwell in 45 outpatients were determined by electron spin resonance spectrometry. The FR levels, clinical parameters, and the level of 8-hydroxy-2'-deoxyguanosine were evaluated at study start. The effects of effluent FR level on technique and patient survival were analyzed in a prospective cohort followed for 24 months., Results: Levels of effluent FRs showed significant negative correlations with daily urine volume and residual renal Kt/V, and positive correlations with plasma β(2)-microglobulin and effluent 8-hydroxy-2'-deoxyguanosine. A highly significant difference in technique survival (p < 0.05), but not patient survival, was observed for patients grouped by effluent FR quartile. The effluent FR level was independently associated with technique failure after adjusting for patient age, history of cardiovascular disease, and presence of diabetes mellitus (p < 0.001). The level of effluent FRs was associated with death-censored technique failure in both univariate (p < 0.001) and multivariate (p < 0.01) hazard models. Compared with patients remaining on PD, those withdrawn from the modality had significantly higher levels of effluent FRs (p < 0.005)., Conclusions: Elevated effluent FRs are associated with RRF and technique failure in stable PD patients. These findings highlight the importance of oxidative stress as an unfavorable prognostic factor in PD and emphasize that steps should be taken to minimize oxidative stress in these patients.

Objectives: Baicalein, a flavonoid derived from the root of Scutelaria baicalensis Georgi, possesses anti-oxidative properties including reactive oxygen species scavenging and lipid peroxidation inhibiting activities. The present study was undertaken to investigate the neuroprotective effect of baicalein against dopamine (DA) neurotoxicity induced by exposure to a synthetic DA precursor, L-3,4-dihydroxyphenylalanine (L-DOPA), in cultured dopaminergic CATH.a cells., Methods and Results: Exposure to L-DOPA for 24 hours reduced the number of viable cells and enhanced protein-bound quinone (quinoprotein) formation in the cell. Both effects were prevented by simultaneous treatment with baicalein. In addition, baicalein prevented the formation of DA semiquinone radicals from DA in an in vitro cell-free system. Long-term baicalein treatment for 96 hours also protected against excess L-DOPA-induced cell death, and also increased glutathione (GSH) levels in CATH.a cells., Discussion: Our results indicate that baicalein has neuroprotective properties against excess L-DOPA-induced DA neurotoxicity through the suppression of DA quinone formation. Furthermore, the long-term treatment of baicalein upregulates intracellular GSH contents, which may also exert neuroprotective effects against oxidative stress-induced neuronal damage.

A cobalt-phosphine complex supported on PS-PEG beads was found to react with a propargyl carbamate tag, and the tagged molecules immobilized on the beads could be released by acidic treatment through the Nicholas reaction pathway. These reactions work in aqueous media at 4 °C, so that this catch and release procedure is compatible with conditions generally used in biochemical experiments.

Almost all mammalian cells carry one primary cilium that functions as a biosensor for chemical and mechanical stimuli. Genetic damages that compromise cilia formation or function cause a spectrum of disorders referred to as ciliapathies. Recent studies have demonstrated that some pharmacological agents and extracellular environmental changes can alter primary cilium length. Renal injury is a well-known example of an environmental insult that triggers cilia length modification. Lithium treatment causes primary cilia to extend in several cell types including neuronal cells;this phenomenon is likely independent of glycogen synthase kinase-3β inhibition. In renal epithelial cell lines, deflection of the primary cilia by fluid shear shortens them by reducing the intracellular cyclic AMP level, leading to a subsequent decrease in mechanosensitivity to fluid shear. Primary cilium length is also influenced by the dynamics of actin filaments and microtubules through the levels of soluble tubulin in the cytosol available for primary cilia extension. Thus, mammalian cells can adapt to the extracellular environment by modulating the primary cilium length, and this feedback system utilizing primary cilia might exist throughout the mammalian body. Further investigation is required concerning the precise molecular mechanisms underlying the control of primary cilium length in response to environmental factors.

Rationale: Negative motivational withdrawal from acute opiate dependence was induced by an opioid antagonist, and the withdrawal signs prevented by pretreatment with nicotine., Objectives: The present study was undertaken to examine the mechanism of nicotine-induced attenuation of withdrawal precipitated by naloxone in rats administered a single dose of morphine., Methods: Conditioned place aversion (CPA) was precipitated by naloxone in rats exposed once to morphine. Nicotinic acetylcholine receptor (nAChR) agonists were microinjected into the central amygdaloid nucleus (CeA) before naloxone was administered. Additionally, c-Fos expression in the amygdala was measured in rats exposed to α7 nAChR ligands., Results: The microinjection of nicotine (0.3 and 1.0 μg/μl) into the CeA dose-dependently inhibited naloxone-induced CPA. This inhibition of CPA was reversed by methyllycaconitine (MLA), an α7 nAChR antagonist. CPA was also significantly attenuated by the microinjection of tropisetron (3.0 μg/μl), an α7 nAChR agonist and 5-hydroxytriptamine 3 (5-HT(3)) receptor antagonist, but not by ondansetron (1.0 and 3.0 μg/μl), a 5-HT(3) receptor antagonist. The microinjection of PNU-282987 (3.0 μg/μl), a selective α7 nAChR agonist, into the CeA also inhibited CPA. Furthermore, nicotine increased c-Fos expression in the CeA, but not the medial or basolateral amygdaloid nucleus. The increase of c-Fos in the CeA was significantly inhibited by MLA., Conclusion: Nicotine-induced attenuation of CPA precipitated by naloxone is mediated by the α7 nAChR subtype, and the CeA is one of the regions of the brain involved in the effect of nicotine on acutely opiate-dependent subjects.

Our previous studies demonstrated the involvement of quinone formation in dopaminergic neuron dysfunction in the L-DOPA-treated parkinsonian model and in methamphetamine (METH) neurotoxicity. We further reported that the cysteine-rich metal-binding metallothionein (MT) family of proteins protects dopaminergic neurons against dopamine (DA) quinone neurotoxicity by its quinone-quenching property. The aim of this study was to examine MT induction in astrocytes in response to excess DA and the potential neuroprotective effects of astrocyte-derived MTs against DA quinone toxicity. DA exposure significantly upregulated MT-1/-2 in cultured striatal astrocytes, but not in mesencephalic neurons. This DA-induced MT upregulation in astrocytes was blocked by treatment with a DA-transporter (DAT) inhibitor, but not by DA-receptor antagonists. Expression of nuclear factor erythroid 2-related factor (Nrf2) and its binding activity to antioxidant response element of MT-1 gene were significantly increased in the astrocytes after DA exposure. Nuclear translocation of Nrf2 was suppressed by the DAT inhibitor. Quinone formation and reduction of mesencephalic DA neurons after DA exposure were ameliorated by preincubation with conditioned media from DA-treated astrocytes. These protective effects were abrogated by MT-1/-2-specific antibody. Adding exogenous MT-1 to glial conditioned media also showed similar neuroprotective effects. Furthermore, MT-1/-2 expression was markedly elevated specifically in reactive astrocytes in the striatum of L-DOPA-treated hemi-parkinsonian mice or METH-injected mice. These results suggested that excess DA taken up by astrocytes via DAT upregulates MT-1/-2 expression specifically in astrocytes, and that MTs or related molecules secreted specifically by astrocytes protect dopaminergic neurons from damage through quinone quenching and/or scavenging of free radicals., (Copyright © 2010 Wiley-Liss, Inc.)

Bacterial lipoproteins are known to be diacylated or triacylated and activate mammalian immune cells via Toll-like receptor 2/6 or 2/1 heterodimer. Because the genomes of low G+C content gram-positive bacteria, such as Staphylococcus aureus, do not contain Escherichia coli-type apolipoprotein N-acyltransferase, an enzyme converting diacylated lipoproteins into triacylated forms, it has been widely believed that native lipoproteins of S. aureus are diacylated. However, we recently demonstrated that one lipoprotein SitC purified from S. aureus RN4220 strain was triacylated. Almost simultaneously, another group reported that another lipoprotein SA2202 purified from S. aureus SA113 strain was diacylated. The determination of exact lipidated structures of S. aureus lipoproteins is thus crucial for elucidating the molecular basis of host-microorganism interactions. Toward this purpose, we intensively used MS-based analyses. Here, we demonstrate that SitC lipoprotein of S. aureus RN4220 strain has two lipoprotein lipase-labile O-esterified fatty acids and one lipoprotein lipase-resistant fatty acid. Further MS/MS analysis of the lipoprotein lipase digest revealed that the lipoprotein lipase-resistant fatty acid was acylated to α-amino group of the N-terminal cysteine residue of SitC. Triacylated forms of SitC with various length fatty acids were also confirmed in cell lysate of the RN4220 and Triton X-114 phase in three other S. aureus strains, including SA113 strain and one Staphylococcus epidermidis strain. Moreover, four other major lipoproteins including SA2202 in S. aureus strains were identified as N-acylated. These results strongly suggest that lipoproteins of S. aureus are mainly in the N-acylated triacyl form., (© 2011 The Authors Journal compilation © 2011 FEBS.)

A 12-year-old girl presented with complaints of headache, lethargy, photophobia, and fever. Cerebrospinal fluid examination revealed bacterial meningitis. Magnetic resonance (MR) imaging showed a cystic lesion with peripheral enhancement in the pituitary fossa. The patient underwent transnasal-transsphenoidal surgery (TSS). The diagnosis was pituitary abscess associated with Rathke's cleft cyst. Postoperatively, the patient recovered rapidly. However, recurrence of the pituitary abscess causing meningitis occurred four times and required repeated TSS. She had diabetes insipidus and received hormone replacement. This case requiring repeated emergency surgeries shows that follow-up examinations including MR imaging and pituitary endocrine evaluation are necessary because the rate of recurrence is high in patients with pituitary abscess associated with Rathke's cleft cyst.

Adult hippocampal neurogenesis is reported to change in animal models of depression and antidepressants. We have used the mitotic marker 5-bromo-2'-deoxyyridine to address the effects of imipramine and lithium on cell proliferation and survival following chronic treatment with adrenocorticotropic hormone (ACTH) in the subgranular zone of the hippocampal dentate gyrus. ACTH treatment for 14 d decreased adult hippocampal cell proliferation and survival. Coadministration of imipramine and lithium for 14 d blocked the loss of cell proliferation but not cell survival resulting from the chronic treatment with ACTH. The coadministration of imipramine and lithium may have treatment-resistant antidepressive properties, which may be attributed, in part, to a normalization of hippocampal cell proliferation.

Metallothionein (MT) is an intracellular metal-binding, cysteine-rich protein, and is a potent antioxidant that protects cells and tissues from oxidative stress. Although the major isoforms MT-1 and -2 (MT-1/-2) are highly inducible in many tissues, the distribution and role of MT-1/-2 in diabetic nephropathy are poorly understood. In this study, diabetes was induced in adult male rats by streptozotocin, and renal tissues were stained with antibodies for MT-1/-2. MT-1/-2 expression was also evaluated in mProx24 cells, a mouse renal proximal tubular epithelial cell line, stimulated with high glucose medium and pretreated with the antioxidant vitamin E. MT-1/-2 expression was gradually and dramatically increased, mainly in the proximal tubular epithelial cells and to a lesser extent in the podocytes in diabetic rats, but was hardly observed in control rats. MT-1/-2 expression was also increased by high glucose stimulation in mProx24 cells. Because the induction of MT was suppressed by pretreatment with vitamin E, the expression of MT-1/-2 is induced, at least in part, by high glucose-induced oxidative stress. These observations suggest that MT-1/-2 is induced in renal proximal tubular epithelial cells as an antioxidant to protect the kidney from oxidative stress, and may offer a novel therapeutic target against diabetic nephropathy.

Bmdsx is a sex-determining gene in the silkworm and is alternatively spliced in males and females. CE1 is a splicing silencer element responsible for the sex-specific splicing of Bmdsx. To identify sex-specific factors implicated in the sex-specific splicing of Bmdsx, we performed RNA affinity chromatography using CE1 RNA as a ligand. We have identified BmIMP, a Bombyx homolog of IGF-II mRNA binding protein (IMP), as a male-specific factor that specifically binds to CE1. The gene encoding BmIMP is localized on the Z chromosome and is male-specifically expressed in various tissues. Antisense inhibition of BmIMP expression increased female-specific splicing of Bmdsx pre-mRNA. Coimmunoprecipitation and glutathione S-transferase (GST) pulldown analyses demonstrated that BmIMP physically interacts with BmPSI, which has been identified as a factor implicated in the sex-specific splicing of Bmdsx, through the KH domains of BmIMP. The functional consequence of this interaction was examined using RNA mobility shift analysis. BmIMP increased BmPSI-CE1 RNA binding activity by decreasing the rate of BmPSI dissociation from CE1 RNA. Truncation analysis of BmIMP suggested that the KH domains are responsible for enhancing BmPSI-CE1 RNA binding activity. These results suggest that BmIMP may enhance the male-specific splicing of Bmdsx pre-mRNA by increasing RNA binding activity of BmPSI.

We examined the influence of chronic adrenocorticotropic hormone (ACTH) treatment on the number of Ki-67-positive cells in the dentate gyrus of the hippocampus in rats. ACTH treatment for 14 days decreased the number of such cells. The administration of imipramine or lithium alone for 14 days had no effect in saline-treated rats. The effect of ACTH was blocked by the administration of imipramine. Furthermore, the coadministration of imipramine and lithium for 14 days significantly increased the number of Ki-67-positive cells in both the saline and ACTH-treated rats. The coadministration of imipramine and lithium normalized the cell proliferation in the dentate gyrus of the hippocampus in rats treated with ACTH.

The dopamine reuptake inhibitor bupropion has clinically been proven to improve depression and treatment-resistant depression. We examined its influence on the duration of immobility during the forced swim test in adrenocorticotropic hormone (ACTH)-treated rats and further analyzed the possible role of dopamine receptors in this effect. Additionally, the mechanism by which bupropion acts in this model was explored specifically in relation to the site of action through the use of microinjections into the medial prefrontal cortex and nucleus accumbens. Bupropion significantly decreased the duration of immobility in normal and ACTH-treated rats. This effect was blocked by D2 and D3 receptor antagonists in normal rats. Furthermore, infusions of bupropion into the nucleus accumbens, but not medial prefrontal cortex, decreased the immobility of normal and ACTH-treated rats during the forced swim test. Bupropion treatment plus repeated ACTH treatment significantly increased the extracellular dopamine concentration. These findings suggest the antidepressant-like effect of bupropion to be related to levels of dopamine in the rat nucleus accumbens.

Amyotrophic lateral sclerosis is a progressive and fatal disease caused by selective death of motor neurons, and a number of these patients carry mutations in the superoxide dismutase 1 (SOD1) gene involved in ameliorating oxidative stress. Recent studies indicate that oxidative stress and disruption of mitochondrial homeostasis is a common mechanism for motor neuron degeneration in amyotrophic lateral sclerosis and the loss of midbrain dopamine neurons in Parkinson's disease. Therefore, the present study investigated the presence and alterations of familial Parkinson's disease-related proteins, PINK1 and DJ-1, in spinal motor neurons of G93ASOD1 transgenic mouse model of amyotrophic lateral sclerosis. Following onset of disease, PINK1 and DJ-1 protein expression increased in the spinal motor neurons. The activated form of p53 also increased and translocated to the nuclei of spinal motor neurons, followed by increased expression of p53-activated gene 608 (PAG608). This is the first report demonstrating that increased expression of PAG608 correlates with activation of phosphorylated p53 in spinal motor neurons of an amyotrophic lateral sclerosis model. These results provide further evidence of the profound correlations between spinal motor neurons of amyotrophic lateral sclerosis and parkinsonism-related proteins.

We focused on thrombocytopenia in hemodialysis patients (HD) receiving recombinant human erythropoietin (rHuEPO) and investigated thrombopoietin (TPO) level and platelet indices. We analyzed platelet parameters including mean platelet volume (MPV), platelet-crit (PCT), mean platelet component (MPC) concentration and platelet count (PLT) using ADVIA 2120 in 375 HD patients. This study included 25 HD patients undergoing treatment with rHuEPO at 9000 IU/week. These patients were divided into two groups by reference PLT of 130 x 10(9)/l [eight patients with low PLT (L-PLT group) and 17 patients with normal PLT (N-PLT group)], and TPO level and platelet indices in each group were compared with those in nine HD patients not receiving rHuEPO. In HD patients, the mean value of MPV was slightly higher and the mean values of PLT, PCT, and MPC were significantly lower than those in healthy controls. TPO levels were significantly higher in patients receiving rHuEPO than in patients not receiving rHuEPO. However, no significant difference was found between TPO levels in patients in the L-PLT group and patients in the N-PLT group. TPO levels were not correlated with PLT in these patients and that MPC levels decreased remarkably regardless of PLT.

Objective: To investigate the clinical feasibility of dual energy subtraction (DES) imaging to improve the delineation of the vocal cord and diagnostic accuracy of vocal cord paralysis as compared with the anterior-posterior view of flat panel detector (FPD) neck radiography., Materials and Methods: For 122 consecutive patients who underwent both a flexible laryngoscopy and conventional/DES FPD radiography, three blinded readers retrospectively graded the radiographs during phonation and inspiration on a scale of 1 (poor) to 5 (excellent) for the delineation of the vocal cord, and in consensus, reviewed the diagnostic accuracy of vocal cord paralysis employing the laryngoscopy as the reference. We compared vocal cord delineation scores and accuracy of vocal cord paralysis diagnosis by both conventional and DES techniques using kappa statistics and assessing the area under the receiver operating characteristic curve (AUC)., Results: Vocal cord delineation scores by DES (mean, 4.2 +/- 0.4) were significantly higher than those by conventional imaging (mean, 3.3 +/- 0.5) (p < 0.0001). Sensitivity for diagnosing vocal cord paralysis by the conventional technique was 25%, whereas the specificity was 94%. Sensitivity by DES was 75%, whereas the specificity was 96%. The diagnostic accuracy by DES was significantly superior (kappa = 0.60, AUC = 0.909) to that by conventional technique (kappa = 0.18, AUC = 0.852) (p = 0.038)., Conclusion: Dual energy subtraction is a superior method compared to the conventional FPD radiography for delineating the vocal cord and accurately diagnosing vocal cord paralysis.

Objective: Recent double-blind, controlled trials in Japan showed that the antiepileptic agent zonisamide (ZNS) improves the cardinal symptoms of Parkinson's disease. Glutathione (GSH) exerts antioxidative activity through quenching reactive oxygen species and dopamine quinone. GSH depletion within dopaminergic neurons impairs mitochondrial complex I activity, followed by age-dependent nigrostriatal neurodegeneration. This study examined changes in GSH and GSH synthesis-related molecules, and the neuroprotective effects of ZNS on dopaminergic neurodegeneration using 6-hydroxydopamine-injected hemiparkinsonian mice brain and cultured neurons or astrocytes., Methods and Results: ZNS increased both the cell number and GSH levels in astroglial C6 cells, but not in dopaminergic neuronal CATH.a cells. Repeated injections of ZNS (30mg/kg intraperitoneally) for 14 days also significantly increased GSH levels and S100beta-positive astrocytes in mouse basal ganglia. Repeated ZNS injections (30mg/kg) for 7 days in the hemiparkinsonian mice increased the expression of cystine/glutamate exchange transporter xCT in activated astrocytes, which supply cysteine to neurons for GSH synthesis. Treatment of these mice with ZNS also increased GSH levels and completely suppressed striatal levodopa-induced quinone formation. Reduction of nigrostriatal dopamine neurons in the lesioned side of hemiparkinsonian mice was significantly abrogated by repeated injections of ZNS with or without adjunctive levodopa starting 3 weeks after 6-hydroxydopamine lesioning., Interpretation: These results provide new pharmacological evidence for the effects of ZNS. ZNS markedly increased GSH levels by enhancing the astroglial cystine transport system and/or astroglial proliferation via S100beta production or secretion. ZNS acts as a neuroprotectant against oxidative stress and progressive dopaminergic neurodegeneration.

The molecular mechanisms underlying the therapeutic effects of lithium, a first-line antimanic mood stabilizer, have not yet been fully elucidated. Treatment of the algae Chlamydomonas reinhardtii with lithium has been shown to induce elongation of their flagella, which are analogous structures to vertebrate cilia. In the mouse brain, adenylyl cyclase 3 (AC3) and certain neuropeptide receptors colocalize to the primary cilium of neuronal cells, suggesting a chemosensory function for the primary cilium in the nervous system. Here we show that lithium treatment elongates primary cilia in the mouse brain and in cultured cells. Brain sections from mice chronically fed with Li(2)CO(3) were subjected to immunofluorescence study. Primary cilia carrying both AC3 and the receptor for melanin-concentrating hormone (MCH) were elongated in the dorsal striatum and nucleus accumbens of lithium-fed mice, as compared to those of control animals. Moreover, lithium-treated NIH3T3 cells and cultured striatal neurons exhibited elongation of the primary cilia. The present results provide initial evidence that a psychotropic agent can affect ciliary length in the central nervous system, and furthermore suggest that lithium exerts its therapeutic effects via the upregulation of cilia-mediated MCH sensing. These findings thus contribute novel insights into the pathophysiology of bipolar mood disorder and other psychiatric diseases.

Nitric oxide (NO) may play a role in the established processes of learning and memory. We examined the effects of N(omega)-nitro-L-arginine methylester (L-NAME), a nonselective inhibitor of NO synthase (NOS), on the performance of mice in a Y-maze task. L-NAME (100 mg/kg) markedly impaired spontaneous alternation behavior. However, galantamine (0.5 mg/kg) significantly attenuated this l-NAME-induced impairment. To clarify the molecular basis underlying galantamine's protective effects against L-NAME-induced impairment of spontaneous alternation behavior, we tested the ability of mecamylamine, an antagonist of nicotinic ACh receptor (nAChR), and scopolamine, an antagonist of muscarinic ACh receptor, to reduce galantamine's protective effects, and found that only the former had such an ability. Galantamine significantly also reduced L-NAME-induced decreases in NOx levels. However, mecamylamine cancelled galantamine's efficacy in countering the L-NAME-induced decrease in NOx levels. In the present study, we have determined that galantamine's protection against L-NAME-induced impairment of spontaneous alternation behavior in the Y-maze task might be mediated mainly by NOergic activation via the nAChR-related pathway.

The Drosophila pericentrin-like protein has been shown to be essential for the formation of the sensory cilia of chemosensory and mechanosensory neurons by mutant analysis in flies, while the in vivo function of pericentrin, a well-studied mammalian centrosomal protein related to microcephalic primordial dwarfism, has been unclear. To determine whether pericentrin is required for ciliogenesis in mammals, we generated and analyzed mice with a hypomorphic mutation of Pcnt encoding the mouse pericentrin. Immunofluorescence analysis demonstrated that olfactory cilia of chemosensory neurons in the nasal olfactory epithelium were malformed in the homozygous mutant mice. On the other hand, the assembly of motile and primary cilia of non-neuronal epithelial cells and the formation of sperm flagella were not affected in the Pcnt-mutant mice. The defective assembly of olfactory cilia in the mutant was apparent from birth. The mutant animals displayed reduced olfactory performance in agreement with the compromised assembly of olfactory cilia. Our findings suggest that pericentrin is essential for the assembly of chemosensory cilia of olfactory receptor neurons, but it is not globally required for cilia formation in mammals.

The dopamine D2/D3 receptor agonist pramipexole has clinically been proven to improve depression or treatment-resistant depression. However, the involvement of the dopamine receptor system on the effect of pramipexole on depression remains unclear. We examined the influence of pramipexole on the duration of immobility during the forced swim test in normal and adrenocorticotropic hormone (ACTH)-treated rats and further analyzed the possible role of dopamine receptors in this effect. Additionally, the mechanism by which pramipexole acts in this model was explored specifically in relation to the site of action through the use of microinjections into the intramedial prefrontal cortex and nucleus accumbens. Pramipexole (0.3-1 mg/kg) significantly decreased the duration of immobility in normal and ACTH-treated rats. This effect was blocked by L-741,626, a D2 receptor antagonist, and nafadotride, a D3 receptor antagonist, in normal rats. Furthermore, infusions of pramipexole into the intranucleus accumbens, but not the medial prefrontal cortex, decreased the immobility of normal and ACTH-treated rats during the forced swim test. Taken together, the results of these experiments suggested that pramipexole, administered into the intranucleus accumbens rather than the medial prefrontal cortex, exerted an antidepressant-like effect on ACTH-treated rats via the dopaminergic system. The immobility-decreasing effect of pramipexole may be mediated by dopamine D2 and D3 receptors.

Sodium dodecyl sulfate (SDS), an anionic surfactant, is widely used in peptide and protein sample preparation. When the sample is analyzed by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS), this surfactant can often cause signal suppression. We have previously reported an on-probe sample preparation method using a suspension of anion-exchange silica gel and sinapinic acid (i.e., gel-SA suspension) as a matrix, thereby greatly improving the MALDI signal detection of the protein solutions containing SDS. In this study, we found that a certain amount of SDS enhanced the MALDI signal intensity for protein samples. This effect was also observed when using sodium decyl sulfate and sodium tetradecyl sulfate instead of SDS. Furthermore, this on-probe sample preparation method using both SDS and the gel-SA suspension improved the detection limit of protein samples in the MALDI-MS analysis by about ten-fold as compared to that of protein samples without SDS and the gel-SA suspension. This method can be applied not only to the MALDI-MS analysis of samples containing SDS, but also to the examination of proteins at femtomole levels or insoluble proteins such as membrane proteins., (Copyright (c) 2009 John Wiley & Sons, Ltd.)

The activity of Rieske non-heme iron oxygenases (aromatic hydrocarbon dioxygenases, AhDOs) is important for the bacterial degradation of aromatic pollutants such as polycyclic aromatic hydrocarbons and dioxins. During our analysis of the role of AhDOs in dioxin bioremediation, some enzymes derived from high G + C Gram-positive actinomycetes were difficult to produce in active form in the Escherichia coli protein expression system. In this study, we constructed a heterologous expression system for AhDOs in Rhodococcus species using a constitutive expression promoter, P(dfdB), and a shuttle vector, pRK401, and analyzed the ability of these enzymes to degrade dibenzofuran and deplete several chlorinated dioxins. Three active AhDOs expressed in Rhodococcus strains that were difficult to obtain by the E. coli system showed different regiospecificities for dibenzofuran bioconversion as well as different substrate depletion specificities for chlorinated dioxins. Moreover, AhDO derived from R. erythropolis TA421 showed relatively diverse depletion-substrate specificity for chlorinated dioxins.

We examined changes in nuclear peroxisome proliferator-activated receptor gamma (PPAR gamma) in the striatum in methamphetamine (METH)-induced dopaminergic neurotoxicity, and also examined effects of treatment with drugs possessing PPAR gamma agonistic properties. The marked reduction of nuclear PPAR gamma-expressed cells was seen in the striatum 3 days after METH injections (4 mg/kg x 4, i.p. with 2-h interval). The reduction of dopamine transporter (DAT)-positive signals and PPAR gamma expression, and accumulation of activated microglial cells were significantly and dose-dependently attenuated by four injections of a nonsteroidal anti-inflammatory drug and a PPAR gamma ligand, ibuprofen (10 or 20 mg/kg x 4, s.c.) given 30 min prior to each METH injection, but not by either a low or high dose of aspirin. Either treatment of ibuprofen or aspirin, that showed no effects on METH-induced hyperthermia, significantly blocked the METH-induced striatal cyclooxygenase (COX) expression. Furthermore, the treatment of an intrinsic PPAR gamma ligand 15d-PG J2 also attenuated METH injections-induced reduction of striatal DAT. Therefore, the present study suggests the involvement of reduction of PPAR gamma expression in METH-induced neurotoxicity. Taken together with the previous report showing protective effects of other PPAR gamma ligand, these results imply that the protective effects of ibuprofen against METH-induced neurotoxicity may be based, in part, on its anti-inflammatory PPAR gamma agonistic properties, but not on its COX-inhibiting property or hypothermic effect.

Dopamine (DA) and its metabolites containing two hydroxyl residues exert cytotoxicity in dopaminergic neuronal cells, primarily due to the generation of highly reactive DA and DOPA quinones. Quinone formation is closely linked to other representative hypotheses such as mitochondrial dysfunction, inflammation, oxidative stress, and dysfunction of the ubiquitin-proteasome system, in the pathogenesis of neurodegenerative diseases such as Parkinson's disease and methamphetamine-induced neurotoxicity. Therefore, pathogenic effects of the DA quinone have focused on dopaminergic neuron-specific oxidative stress. Recently, various studies have demonstrated that some intrinsic molecules and several drugs exert protective effects against DA quinone-induced damage of dopaminergic neurons. In this article, we review recent studies on some neuroprotective approaches against DA quinone-induced dysfunction and/or degeneration of dopaminergic neurons.

Some synthetic lipopeptides, in addition to native lipoproteins derived from both Gram-negative bacteria and mycoplasmas, are known to activate TLR2 (Toll-like receptor 2). However, the native lipoproteins inherent to Gram-positive bacteria, which function as TLR2 ligands, have not been characterized. Here, we have purified a native lipoprotein to homogeneity from Staphylococcus aureus to study as a native TLR2 ligand. The purified 33-kDa lipoprotein was capable of stimulating TLR2 and was identified as a triacylated SitC lipoprotein, which belongs to a family of ATP binding cluster (ABC) transporter substrate-binding proteins. Analyses of the SitC-mediated production of cytokine using mouse peritoneal macrophages revealed that the SitC protein (3 nm) induced the production of tumor necrosis factor-alpha and interleukin-6. Moreover, analysis of knock-out mice showed that SitC required TLR2 and MyD88, but not TLR1 or TLR6, for the induction of cytokines. In addition to the S. aureus SitC lipoprotein, we purified two other native ABC transporter substrate-binding lipoproteins from Bacillus subtilis and Micrococcus luteus, which were both shown to stimulate TLR2. These results demonstrate that S. aureus SitC lipoprotein is triacylated and that the ABC transporter substrate-binding lipoproteins of Gram-positive bacteria function as native ligands for TLR2.

High-dose administration of amphetamine-like compounds is associated with acute behavioral toxicity (including stereotypic and self-injurious behavior and schizophrenic-like psychoses) as well as long-lasting damage to dopaminergic neurons. Several mechanisms are thought to be responsible for methamphetamine-induced neurotoxicity including the formation of reactive oxygen species, dopamine quinones, glutamatergic activity, apoptosis, etc. Recently, new factors regarding glial cell line-derived neurotorophic factor, tumor necrosis factor-alpha, and interferon-gamma have also been associated with methamphetamine-induced neurotoxicity. The objective of this review is to link the behavioral and neurotoxic responses of the amphetamines, emphasizing their common underlying mechanism of monoaminergic release together with inhibition of monoamine oxidase activity. The amphetamine-induced release of dopamine and inhibition of monoamine oxidase increases both cytosolic and synaptic levels of dopamine leading to the acute manifestation of stereotypic and self-injurious behavior. In turn, the enhanced extravesicular levels of dopamine lead to oxidative stress through the generation of reactive oxygen species and dopamine quinones, and cause the long-lasting neuronal damage. Thus, we propose that acute behavioral observation of subjects immediately following methamphetamine administration may provide insight into the long-lasting toxicity to dopaminergic neurons.

Aggregation of proteins in the centrosome is implicated in the pathophysiology of Parkinson's disease. However, the relevance of the centrosome in neurodegeneration is still obscure. Centrosome duplication is initiated by the cyclin E/cyclin-dependent kinase 2 (Cdk2) complex. The present study determined changes in cyclin E or Cdk2 expression and in the centrosomal structure in dopaminergic neuronal CATH.a cells exposed to 50, 100 and 150 micromolar dopamine (DA) for 24 h. DA induced significant increase in Cdk2 protein and cyclin E protein, but not cyclin e mRNA. In DA-treated cells, the intense cyclin E- and Cdk2-immunofluorescence signals were co-localized around large and supernumerary centrosomes, and these two parameters of centrosome amplification were significantly increased compared with the control. Simultaneous co-treatment with DA and a Cdk2 inhibitor blocked centrosome amplification and enhanced cell viability. Our results demonstrated that DA could lead to cyclin E accumulation and Cdk2 up-regulation triggering supernumerary centrosomes and apoptotic cell death.

Background: Coronary ischemia-reperfusion (I/R) injury causes cardiomyocyte necrosis in a multi-step process that includes an inflammatory reaction. A recent study has suggested that high-mobility group box 1 (HMGB1) is a late mediator of lethal sepsis and an early mediator of inflammation and necrosis following I/R injury. In the present study a neutralizing monoclonal antibody (mAb) for HMGB1 was used to clarify the role of HMGB1 in cardiac I/R injury., Methods and Results: Rats underwent 30 min of left coronary artery occlusion followed by 60 min reperfusion. An intravenous injection of anti-HMGB1 mAb or control IgG was administered just before reperfusion. The infarct size was enlarged in the anti-HMGB1 mAb group in comparison with the control group (p<0.05). The treatment of anti-HMGB1 mAb significantly increased the plasma troponin-T and norepinephrine (NE) content in the heart in comparison with the control (p<0.05). Moreover, the production of dihydroxyphenylglycol was reduced in the anti-HMGB1-treated group (p<0.05)., Conclusion: This study shows for the first time the effects of treatment with neutralizing anti-HMGB1 mAb on I/R injury in the rat heart. The findings support the novel view that I/R-induced HMGB1 may be an important factor in the modulation of interstitial NE.

Oxidative stress, including the reactive oxygen or nitrogen species generated in the enzymatical oxidationor auto-oxidation of an excess amount of dopamine, is thought to play an important role in dopaminergic neurotoxicity. Dopamine and its metabolites containing 2 hydroxyl residues exert cytotoxicityin dopaminergic neuronal cells, primarily due to the generation of highly reactive dopamine and DOPA quinones. Dopamine and DOPA quinones may irreversibly alter protein function through the formation of 5-cysteinyl-catechols on the proteins. Furthermore, the quinone formation is closely linked to other representative hypotheses such as mitochondrial dysfunction, inflammation, oxidative stress, and dysfunction of the ubiquitin-proteasome system, in the pathogenesis of neurodegenerative diseases. Therefore, pathogenic effects of the dopamine quinone have recently focused on dopaminergicneuron-specific oxidative stress. In this article, we primarily review recent studies on the pathogenicity of quinone formation, in addition to several neuroprotective approaches against dopaminequinone-induced dysfunction of dopaminergic neurons.

Various hypotheses have been proposed concerning the mechanisms responsible for methamphetamine (METH)-induced neurotoxicity including reactive oxygen species (ROS), dopamine quinones, glutamatergic activity, apoptosis, etc. Recently, new factors regarding glial cell line-derived neurotorophic factor, tumor necrosis factor-alpha, and alpha-synuclein contained in striatal interneural inclusions have also been associated with METH-induced neurotoxicity. In addition, METH-induced self-injurious behavior (SIB) has been proposed to be an acute or immediate behavioral marker predicting the long-lasting neurotoxicity induced by METH. Specifically, it has been proposed that the SIB response may accurately reflect the underlying mechanistic changes occurring in the neuron that eventually result in the long-lasting damage. Several studies have demonstrated that endogenous dopamine (DA) plays an important role in mediating METH-induced neuronal damage. DA release and redistribution from synaptic vesicles to cytoplasmic compartments is thought to involve METH-induced changes in both the vesicular monoamine transporter-2 and DA transporter function. In turn, the consequent elevation of cytosolic auto-oxidizable DA concentrations is thought generate ROS such as superoxide and hydroxyl radicals and cause the DA terminal injury. Finally, the inflammatory response of microglia and glutamatergic toxicity in astrocytes have been related to the METH-induced neurotoxicity. The objective of the present review will be to consolidate the new perspectives in an attempt to formulate a more cohesive explanation of the underlying mechanism responsible for METH-induced DA damage and its early biological markers.

We identified p53-activated gene 608 (PAG608) as a specifically induced gene in striatal tissue of L-DOPA (100mg/kg)-injected hemi-parkinsonian rats using differential display assay. In the present study, we further examined morphological distribution of PAG608 in the central nervous system of L-DOPA-treated hemi-parkinsonian rats. PAG608 expression was markedly induced in fibers and neuronal cells of the lateral globus pallidus and reticular thalamic nucleus adjacent to internal capsule, specifically in the parkinsonian side of L-DOPA-treated models. The protein was also constitutively expressed in motor neurons specifically in either side of the pontine nucleus and motor nuclei of trigeminal and facial nerves. Furthermore, L-DOPA-induced PAG608 expression on motor neurons in the contralateral side of the ventral horn of the spinal cord and the lateral corticospinal tract without cell loss. The specific induction of PAG608 6-48h after L-DOPA injection in the extrapyramidal tracts, pyramidal tracts and corresponding lower motor neurons of the spinal cords suggests its involvement in molecular events in stimulated motor neurons. Taken together with the constitutive expression of PAG608 in the motor nuclei of cranial nerves, PAG608 may be a useful marker of stressed or activated lower motor neurons.

Repeated injections of methamphetamine (METH) cause degeneration of striatal dopaminergic nerve terminals. In the present study, we examined the effects of interferon-gamma (IFN-gamma) on METH-induced striatal neurotoxicity in mice. Intraperitoneal injection of IFN-gamma before METH injection significantly prevented METH-induced reduction of striatal dopamine transporter (DAT)-positive signals and hyperthermia. Furthermore, intracerebroventricular injection of IFN-gamma before METH treatment markedly prevented METH-induced reduction of DAT. Interestingly, central IFN-gamma injection had no effect on METH-induced hyperthermia. In addition, IFN-gamma injected centrally after METH treatment, but not systemically, 1h after the final METH injection significantly protected against METH-induced neurotoxicity. Our results suggest that IFN-gamma injected systemically or its related molecule protects against METH-induced neurotoxicity through intracerebral molecular pathways, while it can prevent METH-induced hyperthermia through different molecular events.