Proteomics approach in the study of the pathophysiology of alcohol-related brain damage

AIMS

Chronic, excessive drinking of alcohol can induce brain damage in the regions important for neurocognitive function. Some of the damage are permanent while some are appearantly reversible. It is our aim to understand the molecular mechanisms underlying alcohol-induced and/or related brain damage, particularly of that observed in 'medically uncomplicated' (without heptatic cirrhosis or Wernicke-Korsakoff Syndrome [WKS]) alcoholics.

METHODS

A high-throughput proteomics technology has been applied to several 'alcohol-sensitive' brain regions from uncomplicated and hepatic cirrhosis-complicated alcoholics to understand the mechanisms of alcohol-related brain damage at the level of protein expression.

RESULTS

It was clearly demonstrated that each brain region reacts in significantly different manner to chronic alcohol ingestion. Appearant abnormalities in vitamin B1 (thiamine)-related biochemical pathways were observed in several brain regions, such as the dorsolateral prefrontal cortex, genu (a frontal part of the corpus callosum) and cerebellar vermis in uncomplicated alcoholics, suggesting that the reduction of this important nutritional component might be associated with brain damage even without the signs of WKS. In addition, in the two different subregions of the corpus callosum (genu and splenium [a posterior part of the corpus callosum]) and the cerebellar vermis, significant differences in protein expression profiles between uncomplicated and complicated alcoholics with hepatic cirrhosis were identified, suggesting that hepatic factors such as ammonia have significant additive influences on brain protein expression, which might lead to the structural changes and/or damage in these brain regions. Furthermore, in the hippocampus, significant change of the level of glutamine synthetase expression was observed, suggesting once again the importance of ammonia as a cause of brain damage in this region.

CONCLUSIONS

Although our data did not show any evidence of "direct" alcohol effects to induce the alteration of protein expression in association with brain damage, high-throughput neuroproteomics approaches are proven to have a potential to dissect the mechanisms of complex brain disorders.

[Inflammatory myofibroblastic tumor of the lung; report of a case]

A 24-year-old male admitted to our hospital with a pulmonary nodule detected by his chest X-ray and computed tomography (CT). His laboratory findings were within normal limits. Chest CT showed a 10 mm solitary nodule in the right lower lobe. Positron emission tomography showed moderately positive detection correspond to the nodule. We couldn't rule out a malignant tumor and performed partial resection of the right lower lobe. Pathological findings definitely revealed pulmonary inflammatory myofibroblastic tumor. This case was reported together with some reviews of the literature.

B cells play a crucial role as antigen-presenting cells and collaborate with inflammatory cytokines in glucose-6-phosphate isomerase-induced arthritis

Anti-glucose-6-phosphate isomerase (GPI) antibodies from K/BxN mice directly induce arthritis; however, the transfer of these antibodies from mice with GPI-induced arthritis does not induce arthritis. CD4(+) T cells play an important role in the induction and effector phase in this model; however, the roles of B cells and immunoglobulins (Igs) have not been elucidated. We investigated the roles of B cells and Igs in GPI-induced arthritis by using adoptive transfer system into SCID mice. Transfer of splenocytes of male DBA/1 mice immunized with GPI into SCID mice induced arthritis on day 6 in the latter, in association with the production of anti-GPI antibodies. Co-localization of C3 and IgG on the articular surface was identified in arthritic SCID mice. Inoculation of IgG (or anti-GPI antibodies) and CD19(+)-depleted splenocytes from arthritic DBA/1 mice induced arthritis in SCID mice, but not CD19(+)-depleted or CD4(+)-depleted splenocytes from DBA/1 mice. In vitro analysis of cytokine production by splenocytes from DBA/1 arthritic mice demonstrated production of large amounts of tumour necrosis factor (TNF)-alpha and interleukin (IL)-6 in an antigen-specific manner (P < 0.01), and production was dominated by CD19(+)-depleted than CD4(+)-depleted splenocytes (P < 0.05). Addition of IgG from DBA/1 arthritic mice to the culture enhanced TNF-alpha but not IL-6 production, and this effect was blocked by anti-Fcgamma receptor antibody. In vivo analysis of neutralization with TNF-alpha protected arthritis completely in SCID mice. Our results highlight the important role of B cells in GPI-induced arthritis as autoantibody producers, and these autoantibodies can trigger joint inflammation in orchestration with inflammatory cytokines, especially TNF-alpha.

Muscarinic-3 acetylcholine receptor autoantibody in patients with systemic sclerosis: contribution to severe gastrointestinal tract dysmotility

OBJECTIVE

Patients with systemic sclerosis (SSc) complicated by severe gastrointestinal tract (GIT) dysmotility at an early stage are difficult to treat and mortality is high. To clarify the pathogenesis of GIT involvement, the occurrence of autoantibody was investigated for muscarinic-3 acetylcholine receptor (M3R) in patients with SSc.

METHODS

Fourteen patients with severe GIT involvement (malabsorption syndrome and/or pseudo-obstruction) within 2 years of SSc onset (group 1) were enrolled in the present study. Sixty-two patients with SSc without severe GIT involvement within 2 years of onset (group 2) were also recruited, along with 70 healthy control subjects. Using an established enzyme immunoassay (EIA) system detecting autoantibody against the second loop domain of M3R, the presence of an anti-M3R antibody was examined in SSc patients.

RESULTS

The mean optical density (OD) titres of group 1 were significantly higher than those of group 2 (0.65 (SD 0.58) vs 0.066 (SD 0.13), p<0.001). The positivity of anti-M3R antibody was significantly higher in group 1 than in group 2 (9/14 vs 3/62, p = 2.5 x 10(-6) by Fisher's exact test). The cutoff OD was calculated from the EIA reaction of the 70 healthy controls (the mean value plus 2 SD was 0.295).

CONCLUSION

The findings indicated that anti-M3R antibody very frequently appears in patients with SSc, which is accompanied by severe GIT involvement, suggesting that M3R-mediated enteric cholinergic neurotransmission may provide a pathogenic mechanism for GIT dysmotility in SSc.

Anti-glucose-6-phosphate isomerase, anti-cyclic citrullinated peptide antibodies and HLA-DRB1 genotypes in Japanese patients with early rheumatoid arthritis

OBJECTIVE

Our goal was to evaluate the associations of antibodies (Abs) to glucose-6-phosphate isomerase (GPI) with Abs to cyclic citrullinated peptide (CCP) and HLA-DRB1 genotypes in Japanese patients with early rheumatoid arthritis (RA).

METHODS

One hundred and eight patients with early RA (85 female, 23 male) who visited our clinic within 1 year of symptom onset were examined for anti-GPI and anti-CCP Ab levels, and HLA-DRB1 genotype. Anti-GPI and anti-CCP Ab levels, and HLA-DRB1 genotypes were also determined in 63 controls and 265 healthy controls, respectively.

RESULTS

Of the 108 patients with early RA and the 63 controls, 20 (18.5%) and 3 (4.8%) were anti-GPI Ab-positive, respectively. Of the 20 patients with anti-GPI Abs, 17 (85%) were positive for anti-CCP Abs. HLA-DRB1*0405 and shared epitope (SE) carrier frequencies were significantly increased not only in anti-GPI Ab-positive patients (p=0.00057, odds ratio [OR] 4.6, 95% CI 1.8-11.8; p=0.0011, OR 5.0, 95% CI 1.7-14.0), but also in anti-GPI Ab-negative patients (p=0.0017, OR 2.2, 95% CI 1.3-3.7; p=0.00011, OR 2.6, 95% CI 1.6-4.3), when compared with controls. In addition, the carrier frequency of HLA-DRB1*1201 was significantly increased in anti-GPI Ab-positive patients compared with controls (p=0.0056, OR 4.3, 95% CI 1.4-13.2).

CONCLUSIONS

The majority of anti-GPI Ab-positive RA patients constitute a subset of HLA-DRB1* SE-associated, anti-CCP Ab-positive RA patients.

Invariant NKT cells produce IL-17 through IL-23-dependent and -independent pathways with potential modulation of Th17 response in collagen-induced arthritis

Invariant natural killer T (iNKT) cells play a protective role in the development of certain autoimmune diseases. However, their precise role in the pathogenesis of autoimmune arthritis remains unclear. In this study, we examined the possible contribution of iNKT cells in collagen-induced arthritis (CIA) by using iNKT cell-deficient mice (Jalpha281-/- mice). CIA in these mice was markedly suppressed and interleukin (IL)-17 production was reduced in a native type II collagen (CII)-specific T cell response. Draining lymph nodes of CII-immunized Jalpha281-/- mice contained a significantly low number of IL-17-producing T helper cells. To determine whether iNKT cells produce IL-17, we measured IL-17 by enzyme-linked immunosorbent assay in iNKT cells stimulated with the ligand, alpha-galactosylceramide (alpha-GalCer). Notably, splenocytes from Jalpha281-/- mice stimulated in this way were negative for IL-17, whereas those from C57BL/6 mice produced IL-17. Immunostaining for IL-17 in iNKT cells confirmed intracellular staining of the protein. RT-PCR analysis showed that iNKT cells expressed retinoid-related orphan receptor gammaT and IL-23 receptor. Moreover, cell sorting demonstrated that NK1.1- iNKT cells were the main producers of IL-17 compared with NK1.1+ iNKT cells. IL-17 production by iNKT cells was induced by IL-23-dependent and -independent pathways, since iNKT produced IL-17 when stimulated with either IL-23 or alpha-GalCer alone. Our findings indicate that iNKT cells are producers and activators of IL-17 via IL-23- dependent and -independent pathways, suggesting that they are key cells in the pathogenesis of CIA through IL-17.

[Multiple schwannoma of the intrathoracic vagal nerve; report of a case]

A 67-year-old male referred to our hospital for the close examination of abnormal chest X-ray findings. Chest X-ray films showed abnormal shadows in the right lung field. Chest computed tomography (CT) scan and magnetic resonance imaging (MRI) revealed the 3 tumors which located in superior, middle and posterior mediastinum. The operation underwent under the diagnosis of neurogenic tumors originating from the right intrathoracic vagal nerve. At the operation, the tumors existed the vagal nerve distal to the recurrent laryngeal nerve and they were resected with the transection of vagal nerve. The masses were histologically diagnosed as schwannoma. We reported a rare case of multiple schwannoma arising from the intrathoracic vagal nerve. He had no postoperative complications, and he has been free from recurrence for 4 years postoperatively.

[Intractable pneumothorax secondary to pulmonary metastasis of angiosarcoma]

A 68-year-old male suffered from right pneumothorax and was admitted to our hospital. He had a previous history of angiosarcoma of the scalp, and had received local resection and chemoradiotherapy. Chest computed tomography (CT) on admission revealed right pneumothorax and bilateral multiple thin-walled cavities of the lung. We performed partial resection of right lung. Histopathological examination showed a small metastatic lesion around the thin-walled cavities of the lung. Four months after the 1st lung resection, he suffered left pneumothorax. We performed partial resection of the left lung. Ten days after the 2nd lung resection, left pneumothorax recurred. Nine days later, he also developed right pneumothorax. We performed the 3rd operation for right lung. Thoracoscopy demonstrated multiple bullas in right lung and it showed impossibility for radical surgery. Although surgical resection for pneumothorax secondary to metastatic lung cancer is usually efficient, it is very hard to manage the pneumothorax of metastatic angiosarcoma.

Protein expression in the nucleus accumbens of rats exposed to developmental vitamin D deficiency

INTRODUCTION

Developmental vitamin D (DVD) deficiency is a candidate risk factor for schizophrenia. Animal models have confirmed that DVD deficiency is associated with a range of altered genomic, proteomic, structural and behavioural outcomes in the rat. Because the nucleus accumbens has been implicated in neuropsychiatric disorders, in the current study we examined protein expression in this region in adult rats exposed to DVD deficiency

METHODS

Female Sprague Dawley rats were maintained on a vitamin D deficient diet for 6 weeks, mated and allowed to give birth, after which a diet containing vitamin D was reintroduced. Male adult offspring (n = 8) were compared to control male (n = 8). 2-D gel electrophoresis-based proteomics and mass spectroscopy were used to investigate differential protein expression.

RESULTS

There were 35 spots, mapped to 33 unique proteins, which were significantly different between the two groups. Of these, 22 were down-regulated and 13 up-regulated. The fold changes were uniformly small, with the largest FC being -1.67. Within the significantly different spots, three calcium binding proteins (calbindin1, calbindin2 and hippocalcin) were altered. Other proteins associated with DVD deficiency related to mitochondrial function, and the dynamin-like proteins.

CONCLUSIONS

Developmental vitamin D deficiency was associated with subtle changes in protein expression in the nucleus accumbens. Disruptions in pathways related to calcium-binding proteins and mitochondrial function may underlie some of the behavioural features associated with animal models of developmental vitamin D deficiency.

Adolescent rats find repeated Delta(9)-THC less aversive than adult rats but display greater residual cognitive deficits and changes in hippocampal protein expression following exposure

The current study examined whether adolescent rats are more vulnerable than adult rats to the lasting adverse effects of cannabinoid exposure on brain and behavior. Male Wistar rats were repeatedly exposed to Delta-9-tetrahydrocannabinol (Delta(9)-THC, 5 mg/kg i.p.) in a place-conditioning paradigm during either the adolescent (post-natal day 28+) or adult (post-natal day 60+) developmental stages. Adult rats avoided a Delta(9)-THC-paired environment after either four or eight pairings and this avoidance persisted for at least 16 days following the final Delta(9)-THC injection. In contrast, adolescent rats showed no significant place aversion. Adult Delta(9)-THC-treated rats produced more vocalizations than adolescent rats when handled during the intoxicated state, also suggesting greater drug-induced aversion. After a 10-15 day washout, both adult and adolescent Delta(9)-THC pretreated rats showed decreased social interaction, while only Delta(9)-THC pretreated adolescent rats showed significantly impaired object recognition memory. Seventeen days following their last Delta(9)-THC injection, rats were euthanased and hippocampal tissue processed using two-dimensional gel electrophoresis proteomics. There was no evidence of residual Delta(9)-THC being present in blood at this time. Proteomic analysis uncovered 27 proteins, many involved in regulating oxidative stress/mitochondrial functioning and cytoarchitecture, which were differentially expressed in adolescent Delta(9)-THC pretreated rats relative to adolescent controls. In adults, only 10 hippocampal proteins were differentially expressed in Delta(9)-THC compared to vehicle-pretreated controls. Overall these findings suggest that adolescent rats find repeated Delta(9)-THC exposure less aversive than adults, but that cannabinoid exposure causes greater lasting memory deficits and hippocampal alterations in adolescent than adult rats.

Proteome analysis of the dorsolateral prefrontal region from healthy individuals

The frontal lobes, particularly the prefrontal region, have been of a great interest to researchers examining human behaviour and the origins of medical conditions involving disturbances in cognitive functions. However, further characterisation of this brain region is necessary to help understand the mechanisms of its disturbance in various disease processes. The work presented here demonstrates the first normative proteomic comparison of the soluble fractions of adjacent grey and white matter of a single brain area with a specific cytoarchitecture, Brodmann area 9 (BA9; part of the dorsolateral prefrontal region). BA9 grey and white matter samples from healthy human brains (i.e. absence of any CNS diseases), were subjected to 2D gel electrophoresis-based proteomics analysis to investigate differential protein expression. The results described herein highlight the importance of correct tissue sampling (i.e. proper separation of grey and white matters) and the necessity for future molecular brain mapping studies. Such studies may provide important information for understanding the molecular basis of the functional differences between grey and white matter and their response to various disease states.

Protein expression profile in the striatum of rats with methamphetamine-induced behavioral sensitization

Repeated administration of methamphetamine (MAP) results in an increased behavioral response to the drug during subsequent exposure. This phenomenon is called behavioral sensitization. Sensitization is an enduring phenomenon, and suggests chronic alterations in neuronal plasticity. MAP-induced sensitization has been proposed and widely investigated as an animal model of MAP psychosis and schizophrenia. However, little is known about the molecular mechanisms underlying MAP-induced sensitization. 2-DE-based proteomics allows us to examine global changes in protein expression in complex biological systems and to propose hypotheses concerning the mechanisms underlying various pathological conditions. In the present study, we examined protein expression profiles in the striatum of MAP-sensitized rats using 2-DE-based proteomics. Repeated administration of MAP (4.0 mg/kg, once a day, intraperitoneal (i.p.)) for 10 days significantly augmented the locomotor response to an MAP challenge injection (1.0 mg/kg, i.p.) on day 11. This enhanced activity was maintained even after a week of drug abstinence. 2-DE analysis revealed 42 protein spots were differentially regulated in the striatum of MAP-sensitized rats compared to control. Thirty-one protein spots were identified using MALDI-TOF, including synapsin II, synaptosomal-associated protein 25 (SNAP-25), adenylyl cyclase-associated protein 1 (CAP1), and dihydropyrimidinase-related protein 2 (DRP2). These proteins can be related to underlying mechanisms of MAP-induced behavioral sensitization, indicating cytoskeletal modification, and altered synaptic function.

[Viral infection after lung transplantation]

We experienced 3 cases of viral infections after lung transplantation. Case 1: Fifty-two-year-old male with pulmonary emphysema underwent left single lung transplantation from a cadaveric donor. Three months after transplantation he presented Epstein-Barr virus (EBV) viremia, resulting in multiple lymphadenopathy. Biopsy showed post-transplant lymphproliferative disorder, and he was treated successfully with rituximab. He is well without recurrence around 1 and a half years after treatment. Case 2: Thitry-eight-year-old male with pulmonary emphysema underwent double lung transplantation from a cadaveric donor. Four months after transplantation he showed multiple nodules in both lungs. Percutaneous biopsy showed post-transplant lymphproliferative disorder, and he was treated successfully with rituximab. He is well without recurrence more than 2 years after treatment. Case 3 : Twenty-four-year-old woman with lymphangioleiomyomatosis underwent living-related bilateral lobar lung transplantation. Three months after lung transplantation she presented cytomegalovirus viremia. Since it proved to be ganciclovir-resistant cytomegalovirus infection, she was treated with foscarnet successfully. She is well without recurrence about 2 and a half years after treatment.

Role of IFN-gamma in an experimental murine model of West Nile virus-induced seizures

Seizures are a major complication of viral encephalitis. However, the mechanisms of seizure-associated neuronal dysfunction remain poorly understood. We report that intranasal inoculation with West Nile virus (WNV) (Sarafend) causes limbic seizures in C57BL/6 mice, but not in interferon (IFN)-gamma-deficient (IFN-gamma-/-) mice. Both strains showed similar levels of virus in the brain, as well as similar concentrations of the cytokines, tumor necrosis factor and interleukin-6, both of which can alter neuronal excitability. Experiments in chimeric IFN-gamma-/- mice reconstituted with IFN-gamma-producing leukocytes showed that IFN-gamma is not required during central nervous system infection for limbic seizure development, suggesting a role for IFN-gamma in the developing brain. This was supported responses to pentylenetetrazole, kainic acid (KA), and N-methyl-d-aspartate (NMDA). Both strains of mice exhibited similar behavior after pentylenetetrazole challenge. However, while NMDA and KA treatment resulted in characteristic seizures in C57BL/6 mice, these responses were diminished (NMDA treatment) or absent (KA treatment) in IFN-gamma-/- mice. Furthermore, NMDA-receptor blockade with MK-801 in WNV-infected C57BL/6 mice abrogated seizures and prolonged survival. Our data show that IFN-gamma plays an important role in the development of the excitatory seizure pathways in the brain and that these cascades become pathogenic in encephalitic WNV infection.