Ki-Wook Oh

Analysis of the C9orf72 hexanucleotide repeat expansion in Korean patients with familial and sporadic amyotrophic lateral sclerosis

The expansion of a noncoding hexanucleotide repeat (GGGGCC) in the chromosome 9 open reading frame (C9orf72) gene has been identified as the most common cause of familial and sporadic amyotrophic lateral sclerosis (ALS) in Caucasian populations. The role of the C9orf72 repeat expansion in Korean ALS patients, however, has not been reported. We therefore investigated the frequency of the C9orf72 repeat expansion in 254 Korean patients with familial (n = 8) and sporadic (n = 246) ALS and found that none of the patients had the expansion. The number of hexanucleotide repeats ranged from 2 to 11 in the 254 ALS patients without the expansion. Our results suggest that the C9orf72 repeat expansion is not the main cause of ALS in the Korean population.

The immunomodulatory effects of human mesenchymal stem cells on peripheral blood mononuclear cells in ALS patients

In a previous study, we reported that intrathecal injection of mesenchymal stem cells (MSCs) slowed disease progression in G93A mutant superoxide dismutase1 transgenic mice. In this study, we found that intrathecal MSC administration vastly increased the infiltration of peripheral immune cells into the spinal cord of Amyotrophic lateral sclerosis (ALS) mice (G93A mutant superoxide dismutase1 transgenic). Thus, we investigated the immunomodulatory effect of MSCs on peripheral blood mononuclear cells (PBMCs) in ALS patients, focusing on regulatory T lymphocytes (Treg; CD4+/CD25high/FoxP3+) and the mRNA expression of several cytokines (IFN‐γ, TNF‐α, IL‐17, IL‐4, IL‐10, IL‐13, and TGF‐β). Peripheral blood samples were obtained from nine healthy controls (HC) and sixteen patients who were diagnosed with definite or probable ALS. Isolated PBMCs from the blood samples of all subjects were co‐cultured with MSCs for 24 or 72 h. Based on a fluorescence‐activated cell sorting analysis, we found that co‐culture with MSCs increased the Treg/total T‐lymphocyte ratio in the PBMCs from both groups according to the co‐culture duration. Co‐culture of PBMCs with MSCs for 24 h led to elevated mRNA levels of IFN‐γ and IL‐10 in the PBMCs from both groups. However, after co‐culturing for 72 h, although the IFN‐γ mRNA level had returned to the basal level in co‐cultured HC PBMCs, the IFN‐γ mRNA level in co‐cultured ALS PBMCs remained elevated. Additionally, the levels of IL‐4 and TGF‐β were markedly elevated, along with Gata3 mRNA, a Th2 transcription factor mRNA, in both HC and ALS PBMCs co‐cultured for 72 h. The elevated expression of these cytokines in the co‐culture supernatant was confirmed via ELISA. Furthermore, we found that the increased mRNA level of indoleamine 2,3‐dioxygenase (IDO) in the co‐cultured MSCs was correlated with the increase in Treg induction. These findings of Treg induction and increased anti‐inflammatory cytokine expression in co‐cultured ALS PBMCs provide indirect evidence that MSCs may play a role in the immunomodulation of inflammatory responses when MSC therapy is targeted to ALS patients.

The advantage of high-resolution MRI in evaluating basilar plaques: A comparison study with MRA

OBJECTIVE Intracranial atherosclerosis (ICAS) is a major cause of ischemic stroke; however it is rather neglected. Vessel wall visualization by high resolution magnetic resonance imaging (HRMRI) might provide more accurate information. METHODS A total of 219 consecutive patients with acute ischemic stroke underwent MRI, MRA and proton-density weighted HRMRI. Using HRMRI, the patients were divided into 3 groups with respect to basilar plaques: no plaque (n = 85), minimal plaque (n = 72) and apparent plaque (n = 62). Demographics and characteristics were compared between the groups, and the extents of stenoses calculated from MRA versus HRMRI data were also compared. Factors potentially associated with basilar plaque were validated by multivariate analysis. RESULTS Patients with apparent plaque had higher frequencies of diabetes mellitus, lower high-density lipoprotein and higher hemoglobin A1c, erythrocyte sedimentation rate and homocysteine. Of the 62 cases of apparent plaque, severe stenosis (>50%) was observed in 10 (16%) by MRA and in 27 (43%) by HRMRI, which points to overestimation of plaques by HRMRI. In addition, no stenosis was evident on MRA in 13 patients with apparent plaque even though they had up to 72% stenosis on HRMRI. After adjusting for covariates, basilar artery apparent plaque was independently associated with old age, previous stroke, diabetes mellitus, low HDL and high levels of homocysteine. CONCLUSIONS Basilar artery stenosis with plaque is more accurately detected using HRMRI than MRA. In addition, the associated risk factors differ somewhat. The use of HRMRI for evaluating ICAS deserves more attention.

Spectrum of cognitive impairment in Korean ALS patients without known genetic mutations.

Background Cognitive impairment is associated with a negative prognosis in amyotrophic lateral sclerosis (ALS), as well as with clinical specificity. We investigate neuropsychological function in ALS patients without known genetic mutations in a Korean tertiary clinic. Methods Three hundred and eighteen patients were enrolled in a prospective longitudinal cohort from September 2008 to February 2012. At the time of diagnosis of sporadic ALS, we carried out genetic and comprehensive neuropsychological tests on all patients, and collected demographic and clinical characteristics. Six cognitive domains, namely executive function, attention, language, calculation, visuospatial function and memory were evaluated. ANOVA and t-tests were used to assess differences in clinical characteristics and neuropsychological parameters between sporadic ALS patients. The Kaplan-Meier method and Cox proportional hazard model were used for survival analysis. Results One hundred and sixty-six patients were categorized into five subtypes: normal cognition (ALS pure), cognitive impairment (ALSci), behavioral impairment (ALSbi), frontotemporal dementia (ALS-FTD), and other types of dementia. Seventy patients (70/166, 42.2%) were cognitively or behaviorally impaired. Among the impaired patients, eight (8/166, 4.8%) had FTD-type dementia and one (1/166, 0.6%) was Alzheimers disease-type. The ALS patients with cognitive impairment (ALSci) and with FTD (ALS-FTD) were more severely impaired in executive function, attention, language and memory than the cognitively intact ALS patients (ALS pure). In a survival analysis, ALSci (β = 1.925, p = 0.025) and ALS-FTD groups (β = 4.150, p = 0.019) tended to have shorter survival than the ALS pure group. Conclusions About half of ALS patients without known genetic variation have cognitive or behavioral impairment. ALS patients with cognitive abnormalities, especially FTD, have a poorer prognosis than those without cognitive impairment. In neuropsychological profiling, executive tasks were effective in identifying cognitive impairment in the ALS patients. It would be useful for clinicians to classify ALS according to neuropsychological profiles, and screen for subtle cognitive impairment.

Safety and efficacy of recombinant human erythropoietin treatment of non-motor symptoms in Parkinson's disease.

BACKGROUND Numerous animal studies and clinical trials have demonstrated that erythropoietin (EPO) has therapeutic effects in ischemic and degenerative diseases. However, few clinical trials have investigated the effect of EPO in Parkinsons disease (PD) patients. This study was an exploratory pilot study to investigate the effects of recombinant human EPO (rhEPO) on motor and non-motor symptoms (NMS) in PD patients. METHODS A total of 26 PD patients at the Hanyang University Hospital were enrolled in the study. The participants were randomly assigned to rhEPO and placebo groups. The rhEPO group was infused intravenously (40,000 IU each) twice a week for 5 weeks. Clinical improvement was estimated using the Unified Parkinsons Disease Rating Scale-III (UPDRS-III), the NMS Scale (NMSS) and the 39-Item Parkinsons Disease Questionnaire (PDQ-39). [(18)F] N-(3-fluoropropyl)-2β-carbon ethoxy-3β-(4-iodophenyl) nortropane (FP-CIT) photon emission tomography (PET) scanning was performed on each participant at baseline and again after 12 months. RESULTS The rhEPO administration significantly improved the NMSS and PDQ-39 scores at 12 months. The UPDRS-III, which reflects motor function, did not change significantly after the rhEPO treatment. With the NMSS, the domains of cardiovascular autonomic function, sleep/fatigue, mood/cognition and attention/memory showed significant changes. None of the participants experienced any serious adverse effects. DISCUSSION We found that rhEPO had beneficial effects on NMS but not on motor function. Dopaminergic refractory NMS, such as cardiovascular autonomic dysfunction and cognition, showed improvement after the administration of rhEPO. Our results suggest that rhEPO might be a good candidate for the treatment of NMS in PD patients.

Mesenchymal Stem Cells Modulate the Functional Properties of Microglia via TGF‐β Secretion

The regulation of microglial cell phenotype is a potential therapeutic intervention in neurodegenerative disease. Previously, we reported that transforming growth factor‐β (TGF‐β) levels in mesenchymal stromal cells (MSCs) could be used as potential biological markers to predict the effectiveness of autologous MSC therapy in patients with amyotrophic lateral sclerosis. However, the underlying mechanism of TGF‐β in MSCs was not fully elucidated in determining the functional properties of microglia. In this study, we aimed to clarify the role of TGF‐β that is involved in MSC effectiveness, especially focusing on microglia functional properties that play a pivotal role in neuroinflammation. We found that MSC‐conditioned media (MSC‐CM) inhibited proinflammatory cytokine expression, restored alternative activated microglia phenotype markers (fractalkine receptor, mannose receptor, CD200 receptor), and enhanced phagocytosis in lipopolysaccharide (LPS)‐stimulated microglia. In addition, TGF‐β in MSC‐CM played a major role in these effects by inhibiting the nuclear factor‐κB pathway and restoring the TGF‐β pathway in LPS‐stimulated microglia. Recombinant TGF‐β also induced similar effects to MSC‐CM in LPS‐stimulated microglia. Therefore, we propose that MSCs can modulate the functional properties of microglia via TGF‐β secretion, switching them from a classically activated phenotype to an inflammation‐resolving phenotype. The latter role may be associated with the inhibition of neuroinflammatory processes in neurodegenerative disorders.

Identification of mutations in Korean patients with amyotrophic lateral sclerosis using multigene panel testing.

Amyotrophic lateral sclerosis (ALS) is a rapidly progressive neurodegenerative disease involving motor neurons. Because a growing number of genes have been identified as the genetic etiology of ALS, simultaneous screening of mutations in multiple genes is likely to be more efficient than gene-by-gene testing. In this study, we performed a multigene panel testing by using targeted capture of 18 ALS-related genes followed by next-generation sequencing. Using this technique, we tried to identify mutations in 4 index patients with familial ALS and 148 sporadic ALS in Korean population and identified 4 known mutations in SOD1, ALS2, MAPT, and SQSTM1 genes, respectively, and 28 variants of uncertain significance in 9 genes. Among the 28 variants of uncertain significance, 6 missense variants were found in highly conserved residues and were consistently predicted to be deleterious by in silico analyses. These results suggest that multigene panel testing is an effective approach for mutation screening in ALS-related genes. Moreover, the relatively low frequency of mutations in known ALS genes implies marked genetic heterogeneity at least in Korean patients with ALS.

De novo FUS mutations in 2 Korean patients with sporadic amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is an adult-onset neurodegenerative disorder. Approximately 5% of ALS patients are familial (fALS) cases, and the remaining 95% are apparently sporadic (sALS) cases. To date, a number of genes have been discovered as associated with ALS, but the genetic background of sALS is not yet fully understood. The occurrence of de novo mutations in ALS genes might be an explanation for sALS, but reduced penetrance could be an alternative theory. Previously, we screened mutations in 5 ALS genes including SOD1 and FUS in 9 fALS and 249 sALS patients and found a total of 15 patients with either SOD1 (7 fALS and 3 sALS) or FUS (1 fALS and 4 sALS) mutations. Interestingly, only 1 fALS patient had the FUS mutation, whereas 4 sALS patients had mutations in this gene. To determine if the FUS mutations in sALS were de novo, we performed genetic analysis on 2 sALS patients with living parents. Genetic analysis confirmed that 2 FUS mutations, including the c.1483C>T (p.Arg495*) and the c.1509_1510delAG (p.Gly504Trpfs*12) mutations, were found only in the patients and not in their parents, confirming the de novo occurrence of these mutations. These findings support the notion that de novo mutations are responsible for a certain proportion of sALS.

Depression and Caregiving Burden in Families of Patients with Amyotrophic Lateral Sclerosis

PURPOSE The purpose of this study was to describe depression, caregiving burden and the correlation of the two variables in the families of patients with amyotrophic lateral sclerosis (ALS) and to clarify factors predicting caregiving burden. METHODS A descriptive and cross-sectional study was conducted with 139 family members who provided care to patients with ALS. The characteristics of patients and families, Korean-Beck Depression Inventory (K-BDI), Korean version of Zarit Burden Interview (K-ZBI) and Korean-Amyotrophic Lateral Sclerosis Functional Rating Scale - Revised (K-ALSFRS-R) were used as study measures. RESULTS The mean score for K-BDI was 19.39 out of 63 suggesting sub-clinical depression and 38.2% of the family members exhibited depression. The mean score for K-ZBI was 66.03 out of 88. The predictors for K-ZBI were K-BDI, age of family member, length of time spent per day in caring, relationship to patient and K-ALSFRS-R. CONCLUSION The results of this study suggest that levels of depression and caregiving burden are high among family members caring for patients with ALS. As depression is associated with caregiving burden, screening and emotional supports should be provided to reduce the burden of care for these family. Support programs to alleviate the care burden are also needed, considering family demographics, time per day in caring giving and K-ALSFRS-R.

Dietary intake of fruits and beta-carotene is negatively associated with amyotrophic lateral sclerosis risk in Koreans: A case-control study

Abstract Objectives Amyotrophic lateral sclerosis (ALS), a rare progressive neurodegenerative disease, has been suggested to have an association with oxidative stress, and thus antioxidant dietary factors may influence pathophysiological mechanisms or the risk of ALS. The purpose of the present study was to investigate the hypothesis that intake of fruits, rich in antioxidant nutrients, is negatively associated with the risk of ALS. Methods Seventy-seven Koreans diagnosed with ALS according to the EI Escorial criteria-revised and the same number of age- and sex-matched healthy controls participated in this study. Dietary intake was estimated using the standardized food frequency questionnaire. Results Multivariate logistic regression analysis showed that fruit consumption was negatively associated with the risk of ALS, but intake of beef, fish, and fast food were positively associated with the risk of ALS. In addition, the risk of ALS was negatively associated with intake of plant calcium and beta-carotene, while positively associated with intake of total calcium and animal calcium. Intake of vegetables and other antioxidant nutrients had no effect on the risk of ALS in the present study. Discussion The intake of fruits and beta-carotene decreases the risk of sporadic ALS in this present study. However, large prospective and interventional studies are needed to confirm the effect of fruits and beta-carotene intake on the risk of ALS.