Rivastigmine Improves Appetite by Increasing the Plasma Acyl/Des-Acyl Ghrelin Ratio and Cortisol in Alzheimer Disease.

BACKGROUND: Weight loss accelerates cognitive decline and increases mortality in patients with dementia. While acetylcholinesterase (AChE) inhibitors are known to cause appetite loss, we sometimes encounter patients in whom switching from donepezil (AChE inhibitor) to rivastigmine (AChE and butyrylcholinesterase [BuChE] inhibitor) improves appetite. Since BuChE inactivates ghrelin, a potent orexigenic hormone, we speculated that rivastigmine improves appetite by inhibiting BuChE-mediated ghrelin inactivation. METHODS: The subjects were patients with mild to moderate Alzheimer disease treated with either rivastigmine patch (n = 11) or donepezil (n = 11) for 6 months. Before and after treatment, we evaluated appetite (0, decreased; 1, slightly decreased; 2, normal; 3, slightly increased; 4, increased), cognitive function, and blood biochemical variables, including various hormones. RESULTS: Rivastigmine treatment significantly improved appetite (from 1.6 ± 0.5 to 2.6 ± 0.7), whereas donepezil treatment did not (from 2.0 ± 0.0 to 1.8 ± 0.4). Simultaneously, rivastigmine, but not donepezil, significantly decreased the serum cholinesterase activity (from 304.3 ± 60.5 to 246.8 ± 78.5 IU/L) and increased the cortisol level (from 11.86 ± 3.12 to 14.61 ± 3.29 µg/dL) and the acyl/des-acyl ghrelin ratio (from 4.03 ± 2.96 to 5.28 ± 2.72). The levels of leptin, insulin, total ghrel-in, and cognitive function were not significantly affected by either treatment. CONCLUSIONS: Our results suggest that compared with donepezil, rivastigmine has the advantage of improving appetite by increasing the acyl/des-acyl ghrelin ratio and cortisol level, thereby preventing weight loss.

Step Numbers and Hoehn-Yahr Stage after Six Years.

BACKGROUND: Freezing of gait (FOG) has been linked to increased numbers of steps taken while walking. We tested the hypothesis that an increased number of steps associated with FOG might predict the exacerbation of the severity of Parkinson's disease (PD). METHODS: We prospectively studied 26 patients. Clinical assessments were performed and balance was evaluated in 30 patients with Hoehn-Yahr stage III PD 6 years previously. Gait parameters were analyzed with the use of an originally designed, suddenly narrowed path. PD-related independent variables, balance investigation-related variables, and gait-independent-related variables were analyzed by multiple logistic regression analysis. RESULTS: The Hoehn-Yahr stage increased in 14 patients and was unchanged in 12 patients. The 36-item Short-Form Health Survey score (OR 1.079, p = 0.041, 95% CI 1.003-1.161) and the number of steps on the suddenly narrow path (OR 1.605, p = 0.047, 95% CI 1.006-2.56) were related to an increase in the Hoehn-Yahr stage. The number of steps was significantly higher on the suddenly narrowed path (11.3 ± 3.6) than on a straightly narrowed path (10.1 ± 3.2) at the time of final follow-up in the 26 patients (p < 0.001). CONCLUSIONS: An increased number of steps associated with FOG, which was elicited by the suddenly narrowed path, might be one predictor of an upgrade of stage in patients with Hoehn-Yahr stage III PD.

Comparison of brain 3.0-T with 1.5-T MRI in patients with multiple sclerosis: a 6-month follow-up study.

OBJECTIVES: The 2010 revisions to the McDonald criteria for the diagnosis of multiple sclerosis (MS) were recently published. One objective of the revision was to simplify the MRI criteria. The MRI criteria do not specify magnetic field strength. We studied whether there was any difference in diagnosis between brain 3.0-T and 1.5-T MRI according to the 2010 revisions of the McDonald criteria. PATIENTS AND METHODS: We prospectively studied brain 3.0-T and 1.5-T MRI in 22 patients with MS. 1.5-T MRI was performed 24h after 3.0-T MRI, and the scanning protocol included contiguous axial sections of T2-weighted images (T2WI), T1WI, and enhanced T1WI. These two different MRI and neurological assessments were scheduled to be repeated 3 and 6 months after study entry. RESULTS: The regions where MS lesions were better visualized on 3.0-T MRI tended to be in deep white matter on T2WI. Dissemination of lesions in space and time was similar for 3.0-T and 1.5-T MRI. CONCLUSION: Our study found no difference between brain 3.0-T and 1.5-T MRI. There was no apparent impact of brain 3.0-T MRI on the diagnosis of MS according to the 2010 version of the MRI criteria.

[Metabolic syndrome].

Considerable attention has focused on the prevention of dementia in terms of non-genetic risk factors, including midlife obesity, especially visceral obesity associated with hyperglycemia, hypertension, and hypercholesterolemia. Accumulating evidence has indicated that the increased insulin resistance in relation to visceral fat accumulation is potential risk of Alzheimer's disease (AD) and vascular dementia. Reducing the accumulating visceral fat may contribute to reduce the risk of on set and progression of AD and vascular dementia. Treatment with renin-angiotensin system blockers in hypertension might slow the rate of cognitive decline in patients with AD by modulating insulin resistance.

Renin-angiotensin system blockers affect cognitive decline and serum adipocytokines in Alzheimer's disease.

BACKGROUND: Accumulating evidence indicates an association of Alzheimer's disease (AD) with the metabolic syndrome (MetS), characterized by visceral fat accumulation with insulin resistance and altered secretion of adipocytokines such as adiponectin and leptin. The renin-angiotensin system (RAS) regulates blood pressure and insulin resistance. Recent studies suggest that the RAS plays crucial roles in cognitive functions and that adipocytokines exert neuroprotective activity in the brain. We investigated whether RAS blockers (RASB) affect adipocytokines and cognitive function in patients with AD. METHODS: We studied 78 patients with a diagnosis of probable AD according to the Diagnostic and Statistical Manual of Mental Disorders, 4th edition and 106 nondemented control subjects who visited our clinic with a main complaint of headache or dizziness. We examined retrospectively the effects of RASB on adipocytokines and cognitive decline in patients with AD who were divided into three groups: hypertension treated with RASB (HT-RASB; n = 17), hypertension treated with other antihypertensive drugs (HT-other; n = 34), and no hypertension (non-HT; n = 27). RESULTS: The HT-RASB group had a significantly higher serum leptin level and a relatively larger visceral fat area than the other groups, because of the bias toward patients with MetS in this group. The HT-RASB group also had a significantly lower immunoreactive insulin level, a relatively low homeostasis model assessment as an index of insulin resistance, and a relatively high serum adiponectin level among the three groups. Cognitive decline, estimated on the basis of the mean annual decline using the Hasegawa Dementia Scale score was significantly low in the HT-RASB group. CONCLUSION: Treatment with RASB might modulate serum adipocytokines and glucose homeostasis, potentially slowing cognitive decline in patients with AD.

Complete Remission of Generalized Myasthenia Gravis by Corticosteroid Treatment Alone without Thymectomy.

Many long-term, follow-up studies have shown that steroids are effective in patients with myasthenia gravis (MG) who have undergone thymectomy. However, few long-term studies have documented the response of MG to steroids alone. We describe two patients who successfully resolved the symptoms of MG without myasthenic crisis or serious side effects by steroid treatment without thymectomy or other alternative therapies for more than 19 years. Our experiences raise an open question of the role of thymectomy or steroid treatment alone, especially in MG patients without thymoma.

Risk of falling in Parkinson's disease at the Hoehn-Yahr stage III.

BACKGROUND: It is difficult to predict the risk of falling, especially in patients with good motor ability, and the mechanisms underlying the relation between gait patterns and falling in Parkinson's disease (PD) remain unclear. We investigated factors related to falling, including walking speed and time, in patients with Hoehn-Yahr stage III PD. METHODS: We performed clinical assessments and evaluated balance in 30 patients with PD. Information on falling was obtained from questionnaires and personal interviews. Gait patterns were analyzed with the use of an originally designed, suddenly narrowed path. RESULTS: Gait velocity was slower in fallers than in non-fallers (p = 0.047). Unified Parkinson's Disease Rating Scale part II (UPDRS part II) score, fear of falling, and gait velocity were significantly related to falling on analysis with a single logistic model. When a multiple logistic model was used, the UPDRS part II score was significantly related to falling (OR: 1.48, p = 0.037, 95% CI: 1.02-2.16). CONCLUSIONS: Patients with Hoehn-Yahr stage III PD showed slow gait velocity attributed to fear of falling before arrival at a narrowed entrance or while walking on a narrowed path. The UPDRS part II score is significantly related to the risk of future falls.

Characteristic neuroimaging in patients with tumefactive demyelinating lesions exceeding 30 mm.

BACKGROUND AND PURPOSE: Features of tumefactive demyelinating lesion (TDL) on magnetic resonance imaging (MRI) can facilitate the differential diagnosis of TDL and neoplastic lesions, but vary considerably among patients. The larger TDL grows, the more difficult it becomes to differentiate TDL from neoplastic lesions. The purpose of this study was to elucidate typical MRI features in 12 patients with large TDL (>30 mm in diameter). METHODS: We identified 12 patients with large TDL (six men, six women; age range 17-64 years, median age 27 years) and studied the clinical histories and the results of laboratory and various radiological studies in these patients. All cases of clinically definite multiple sclerosis were diagnosed in accordance with McDonald's revised criteria. RESULTS: Common MRI features of large TDLs included variable degrees of mass effect (71%) and edema (100%), a T2 hypointense rim (79%), venular enhancement (57%), and peripheral restriction on diffusion-weighted images (50%). Ring enhancement (38%), open-ring enhancement (31%), or decreased N-acetylaspartate ratios on magnetic resonance spectroscopy (22%) were less frequently observed. Brain angiography demonstrated venous dilatations on and around the TDL. CONCLUSIONS: The diagnosis of large TDL is challenging. Our findings suggest that multiple venous dilatations on and around TDLs on angiography can facilitate diagnosis.

Protein kinase C gamma, a protein causative for dominant ataxia, negatively regulates nuclear import of recessive-ataxia-related aprataxin.

Spinocerebellar ataxia type 14 (SCA14) is an autosomal dominant disease caused by mutations in the gene encoding protein kinase C gamma (PKC gamma). We report an SCA14 family with a novel deletion of a termination-codon-containing region, resulting in a missense change and a C-terminal 13-amino-acid extension with increased kinase activity. Notably, one patient with a severe phenotype is the first homozygote for the mutation causing SCA14. We show the novel molecular consequences of increased kinase activities of mutants: aprataxin (APTX), a DNA repair protein causative for autosomal recessive ataxia, was found to be a preferential substrate of mutant PKC gamma, and phosphorylation inhibited its nuclear entry. The phosphorylated residue was Thr111, located adjacent to the nuclear localization signal, and disturbed interactions with importin alpha, a nuclear import adaptor. Decreased nuclear APTX increased oxidative stress-induced DNA damage and cell death. Phosphorylation-resistant APTX, kinase inhibitors, and antioxidants may be therapeutic options for SCA14.

Peripheral neuropathy in chromosome16q22.1 linked autosomal dominant cerebellar ataxia.

Autosomal dominant cerebellar ataxia (ADCA) includes heterogeneous neurodegenerative diseases with or without various neurological signs and symptoms. Ishikawa et al reported a new type of ADCA, named chromosome16q22.1 linked ADCA (16q-ADCA), attributed to a heterozygous C→T substitution in the 5' non-coding region of puratrophin-1 gene. We searched for this mutation in168 patients from 129 families with ADCA and found it in six patients. The patients generally showed late onset pure cerebellar ataxia similar to previous reports but two had mild axonal neuropathy and orthostatic hypotension (OH). Our results suggest that 16q-ADCA shows a broader clinical presentation than previously thought.

Cerebrospinal fluid-orexin levels and sleep attacks in four patients with Parkinson's disease.

OBJECTIVES: Sleep attacks (SAs) in Parkinson's disease (PD) are rare, but clinically important because they significantly impair the daily lives of patients. Causes of SAs include long-term activation of dopaminergic (especially D3) receptors. Recent studies suggest that SAs in PD may be related to impairment of hypothalamic orexin neurons, similar to narcolepsy. Whether orexin is associated with long-term activation of dopaminergic receptors remains uncertain. PATIENTS AND METHODS: We measured levels of orexin in samples of spinal cerebrospinal fluid (CSF) from 25 patients with PD, including 9 with excessive daytime sleepiness and 4 with SAs. Furthermore, in the four patients with SAs, the selective dopamine D1/D2 agonist pergolide was substituted for the causative drugs with D3 stimulatory activity, and CSF-orexin levels were measured before and after switching treatment. RESULTS: In the 25 patients with PD, including the 4 patients with SAs, lower CSF-orexin levels were associated with a longer disease duration, which has been linked to a higher incidence of SAs. Switching treatment to pergolide significantly increased CSF-orexin levels and completely resolved SAs in the four patients with PD. CONCLUSION: Despite the small number of patients studied, our results suggest that orexin transmission is most likely involved in SAs in PD and that abrogation of D3 receptor stimulation may increase orexin and thereby inhibit SAs.

Complete recovery of an aged patient with Guillain-Barré syndrome associated with multiple IgM anti-ganglioside antibodies.

In this report we describe a 72-year-old woman who had cytomegalovirus infection-related Guillain-Barré syndrome (GBS) associated with multiple immunoglobulin M (IgM) anti-ganglioside antibodies. She became tetraplegic with respiratory failure, but recovered completely after intravenous immunoglobulin therapy and plasmapheresis. The serum contained high-titer IgM antibody activities to several gangliosides with disialosyl residues (GD1b, GD3, GT1b, GQ1b, and GT1a) and GD1a. These antibodies are often found in sera from patients with chronic sensory ataxic neuropathy, but they occur rarely in GBS.

Limbic encephalitis with involvement of prefrontal cortices and persistent amnesia.

OBJECTIVES: Most abnormalities on magnetic resonance imaging (MRI) in limbic encephalitis involve the medial temporal lobes and are associated with memory impairment. Recent neuroimaging studies have shown that not only the medial temporal lobes, but also the prefrontal lobes, contribute to cognitive functions. METHODS: We describe a case of limbic encephalitis with abnormalities in the medial temporal lobes on MRI and decreased accumulation of radionuclide in the prefrontal regions on SPECT. RESULTS: The patient had persistent retrograde amnesia, particularly affecting remotely acquired memories including public events and autobiographical memories. CONCLUSION: Disruption of the prefrontal-medial temporal circuitry by intense inflammation may have initiated the metabolic changes in the prefrontal cortices, which may exacerbate amnesia.

Restoration of nuclear-import failure caused by triple A syndrome and oxidative stress.

Triple A syndrome is an autosomal recessive neurological disease, mimicking motor neuron disease, and is caused by mutant ALADIN, a nuclear-pore complex component. We recently discovered that the pathogenesis involved impaired nuclear import of DNA repair proteins, including DNA ligase I and the cerebellar ataxia causative protein aprataxin. Such impairment was overcome by fusing classical nuclear localization signal (NLS) and 137-aa downstream sequence of XRCC1, designated stretched NLS (stNLS). We report here that the minimum essential sequence of stNLS (mstNLS) is residues 239-276, downsized by more than 100 aa. mstNLS enabled efficient nuclear import of DNA repair proteins in patient fibroblasts, functioned under oxidative stress, and reduced oxidative-stress-induced cell death, more effectively than stNLS. The stress-tolerability of mstNLS was also exerted in control fibroblasts and neuroblastoma cells. These findings may help develop treatments for currently intractable triple A syndrome and other oxidative-stress-related neurological diseases, and contribute to nuclear compartmentalization study.

Short half-lives of ataxia-associated aprataxin proteins in neuronal cells.

Early-onset ataxia with ocular motor apraxia and hypoalbuminemia (EAOH)/ataxia with oculomotor apraxia type 1 (AOA1) is caused by mutations in the gene encoding aprataxin (APTX). Although several in vitro findings proposed that impaired enzymatic activities of APTX are responsible for EAOH/AOA1, potential instability of mutant proteins has also been suggested as the pathogenesis based on in vivo finding that mutant proteins are almost undetectable in EAOH/AOA1 tissues or cells. The present study aimed to experimentally prove instability of mutant proteins in neuronal cells, the cell type preferentially affected by this disease. Results of pulse-chase experiments demonstrated that all of the disease-associated mutants had extremely shorter half-lives than the WT. We further found that mutants were targeted for rapid proteasome-mediated degradation. These results help establish pathogenic and physiological protein characteristics of APTX in neuronal cells.

SPECT revealed cortical dysfunction in a patient who had genetically definite megalencephalic leukoencephalopathy with subcortical cysts.

We describe the findings on single photon emission computed tomography (SPECT) in a patient who had genetically definite megalencephalic leukoencephalopathy with subcortical cysts. Technetium-99m-ethyl cysteinate dimer SPECT revealed hypoperfusion in the cerebral white matter, which had shown high signal intensity on magnetic resonance imaging (MRI) T2 images. Hypoperfusion was also unexpectedly found in the frontal cortices, which showed no abnormalities on MRI. This frontal abnormality corresponded clinically to a low score on the frontal assessment battery. Decreased GABA receptor density as suggested by (123)I-Iomazenil SPECT provided further evidence of cortical neuron dysfunction. Although confirmation must await future larger-scale SPECT and functional studies, our findings suggest that SPECT can be used to non-invasively monitor in vivo cortical function in this disease.

DNA single-strand break repair is impaired in aprataxin-related ataxia.

OBJECTIVE: Early-onset ataxia with ocular motor apraxia and hypoalbuminemia (EAOH)/ataxia with oculomotor apraxia type 1 (AOA1) is an autosomal recessive form of cerebellar ataxia. The causative protein for EAOH/AOA1, aprataxin (APTX), interacts with X-ray repair cross-complementing 1 (XRCC1), a scaffold DNA repair protein for single-strand breaks (SSBs). The goal of this study was to prove the functional involvement of APTX in SSB repair (SSBR). METHODS: We visualized the SSBR process with a recently developed laser irradiation system that allows real-time observation of SSBR proteins and with a local ultraviolet-irradiation system using a XPA-UVDE cell line that repairs DNA lesions exclusively via SSBR. APTX was knocked down using small interference RNA in the cells. Oxidative stress-induced DNA damage and cell death were assessed in EAOH fibroblasts and cerebellum. RESULTS: Our systems showed the XRCC1-dependent recruitment of APTX to SSBs. SSBR was impaired in APTX-knocked-down cells. Oxidative stress in EAOH fibroblasts readily induced SSBs and cell death, which were blocked by antioxidants. Accumulated oxidative DNA damage was confirmed in EAOH cerebellum. INTERPRETATION: This study provides the first direct evidence for the functional involvement of APTX in SSBR and in vivo DNA damage in EAOH/AOA1, and suggests a benefit of antioxidant treatment.

Interferon causes no myasthenia in a seropositive patient with multiple sclerosis.

We describe a successful outcome of long-term interferon beta-1b therapy in a patient who had multiple sclerosis (MS) with positive serum autoantibody to muscle acetylcholine receptor (AChR-Ab). Because of the reported possible causative linkage between interferon beta-1b and myasthenia gravis (MG), the presence of the pathogenic antibody complicated therapeutic strategies. We carefully observed the patient for further 6 months before the treatment, excluding symptomatic MG. The interferon beta-1b therapy then provided a clinical benefit. Hopefully this report will allow MS patients in similar situations to make more rapid, unprejudiced judgments than our patients.