Etv5a Suppresses Neural Progenitor Cell Proliferation by Inhibiting sox2 Transcription.

Neural progenitor cells are self-renewable, proliferative, and multipotent cell populations that generate diverse types of neurons and glia to build the nervous system. Transcription factors play critical roles in regulating various cellular processes; however, the transcription factors that regulate the development of neural progenitors are yet to be identified. In the present study, we demonstrated that zebrafish etv5a is expressed in the neural progenitor cells of the neuroectoderm. Downregulation of endogenous Etv5a function by etv5a morpholino or an etv5a dominant-negative variant increased the proliferation of sox2-positive neural progenitor cells, accompanied by inhibition of neurogenesis and gliogenesis. These phenotypes in Etv5a-depleted embryos could be rescued by a co-injection with etv5a cRNA. Etv5a overexpression reduced sox2 expression. Direct binding of Etv5a to the regulatory elements of sox2 was affirmed by chromatin immunoprecipitation. These data revealed that Etv5a directly suppressed sox2 expression to reduce the proliferation of neural progenitor cells. In addition, the expression of foxm1, a putative target gene of Etv5a and a direct upstream transcription factor of sox2, was upregulated in Etv5a-deficient embryos. Moreover, the suppression of Foxm1 function by the foxm1 dominant-negative construct nullified the phenotype of upregulated sox2 expression caused by Etv5a deficiency. Overall, our results indicated that Etv5a regulates the expression of sox2 via direct binding to the sox2 promoter and indirect regulation by inhibiting foxm1 expression. Hence, we revealed the role of Etv5a in the transcriptional hierarchy that regulates the proliferation of neural progenitor cells.

HCH6-1, an antagonist of formyl peptide receptor-1, exerts anti-neuroinflammatory and neuroprotective effects in cellular and animal models of Parkinson's disease.

Microglial activation-induced neuroinflammation contributes to onset and progression of sporadic and hereditary Parkinson's disease (PD). Activated microglia secrete pro-inflammatory and neurotoxic IL-1ß, IL-6 and TNF-α, which subsequently promote neurodegeneration. Formyl peptide receptor-1 (FPR1) of CNS microglia functions as pattern recognition receptor and is activated by N-formylated peptides, leading to microglial activation, induction of inflammatory responses and resulting neurotoxicity. In this study, it was hypothesized that FPR1 activation of microglia causes loss of dopaminergic neurons by activating inflammasome and upregulating IL-1ß, IL-6 or TNF-α and that FPR1 antagonist HCH6-1 exerts neuroprotective effect on dopaminergic neurons. FPR1 agonist fMLF induced activation of microglia cells by causing activation of NLRP3 inflammasome and upregulation and secretion of IL-1ß, IL-6 or TNF-α. Conditioned medium (CM) of fMLF-treated microglia cells, which contains neurotoxic IL-1ß, IL-6 and TNF-α, caused apoptotic death of differentiated SH-SY5Y dopaminergic neurons by inducing mitochondrial oxidative stress and activating pro-apoptotic signaling. FPR1 antagonist HCH6-1 prevented fMLF-induced activation of inflammasome and upregulation of pro-inflammatory cytokines in microglia cells. HCH6-1 co-treatment reversed CM of fMLF-treated microglia-induced apoptotic death of dopaminergic neurons. FPR1 antagonist HCH6-1 inhibited rotenone-induced upregulation of microglial marker Iba-1 protein level, cell death of dopaminergic neurons and motor impairment in zebrafish. HCH6-1 ameliorated rotenone-induced microglial activation, upregulation of FPR1 mRNA, activation of NLRP3 inflammasome, cell death of SN dopaminergic neurons and PD motor deficit in mice. Our results suggest that FPR1 antagonist HCH6-1 possesses anti-neuroinflammatory and neuroprotective effects on dopaminergic neurons by inhibiting microglial activation and upregulation of inflammasome activity and pro-inflammatory cytokines.

Deficiency of RAB39B Activates ER Stress-Induced Pro-apoptotic Pathway and Causes Mitochondrial Dysfunction and Oxidative Stress in Dopaminergic Neurons by Impairing Autophagy and Upregulating α-Synuclein.

Deletion and missense or nonsense mutation of RAB39B gene cause familial Parkinson's disease (PD). We hypothesized that deletion and mutation of RAB39B gene induce degeneration of dopaminergic neurons by decreasing protein level of functional RAB39B and causing RAB39B deficiency. Cellular model of deletion or mutation of RAB39B gene-induced PD was prepared by knocking down endogenous RAB39B in human SH-SY5Y dopaminergic cells. Transfection of shRNA-induced 90% reduction in RAB39B level significantly decreased viability of SH-SY5Y dopaminergic neurons. Deficiency of RAB39B caused impairment of macroautophagy/autophagy, which led to increased protein levels of α-synuclein and phospho-α-synucleinSer129 within endoplasmic reticulum (ER) and mitochondria. RAB39B deficiency-induced increase of ER α-synuclein and phospho-α-synucleinSer129 caused activation of ER stress, unfolded protein response, and ER stress-induced pro-apoptotic cascade. Deficiency of RAB39B-induced increase of mitochondrial α-synuclein decreased mitochondrial membrane potential and increased mitochondrial superoxide. RAB39B deficiency-induced activation of ER stress pro-apoptotic pathway, mitochondrial dysfunction, and oxidative stress caused apoptotic death of SH-SY5Y dopaminergic cells by activating mitochondrial apoptotic cascade. In contrast to neuroprotective effect of wild-type RAB39B, PD mutant (T168K), (W186X), or (G192R) RAB39B did not prevent tunicamycin- or rotenone-induced increase of neurotoxic α-synuclein and activation of pro-apoptotic pathway. Our results suggest that RAB39B is required for survival and macroautophagy function of dopaminergic neurons and that deletion or PD mutation of RAB39B gene-induced RAB39B deficiency induces apoptotic death of dopaminergic neurons via impairing autophagy function and upregulating α-synuclein.

Mangosteen Pericarp Extract Supplementation Boosts Antioxidant Status via Rebuilding Gut Microbiota to Attenuate Motor Deficit in 6-OHDA-Induced Parkinson's Disease.

Oxidative stress and gut dysbiosis have been known to precede Parkinson's disease (PD). An antioxidant-rich product, mangosteen pericarp (MP), has the ability to counterbalance excessive free radicals and the imbalanced gut microbiota composition, suggesting the MP's capacity to delay PD progression. In this study, we explored the effects of two doses of MP extract in a unilateral 6-hydroxydopamine (6-OHDA)-induced PD rat model. We revealed that the 8-week supplementation of a low dose (LMP) and a high dose of the MP extract (HMP) improved motor function, as observed in decreased contralateral rotation, improved time spent on rod, and higher dopamine binding transporter (DAT) in the substantia nigra pars compacta (SNc). The MP extract, especially the HMP, also increased antioxidant-related gene expressions, restored muscle mitochondrial function, and remodeled fecal microbiota composition, which were followed by reduced reactive oxygen species levels in brain and inflammation in plasma. Importantly, bacterial genera Sutterella, Rothia, and Aggregatibacter, which were negatively correlated with antioxidant gene expressions, decreased in the HMP group. It is imperative to note that in addition to directly acting as an antioxidant to reduce excessive free radicals, MP extract might also increase antioxidant state by rebuilding gut microbiota, thereby enhanced anti-inflammatory capacity and restored mitochondrial function to attenuate motor deficit in 6-OHDA-induced PD-like condition. All in all, MP extract is a potential candidate for auxiliary therapy for PD.

Probiotic Enhancement of Antioxidant Capacity and Alterations of Gut Microbiota Composition in 6-Hydroxydopamin-Induced Parkinson's Disease Rats.

Oxidative stress plays a key role in the degeneration of dopaminergic neurons in Parkinson's disease (PD), which may be aggravated by concomitant PD-associated gut dysbiosis. Probiotics and prebiotics are therapeutically relevant to these conditions due to their antioxidant, anti-inflammatory, and gut microbiome modulation properties. However, the mechanisms by which probiotic/prebiotic supplementation affects antioxidant capacity and the gut microbiome in PD remains poorly characterized. In this study, we assessed the effects of a Lactobacillus salivarius AP-32 probiotic, a prebiotic (dried AP-32 culture medium supernatant), and a probiotic/prebiotic cocktail in rats with unilateral 6-hydroxydopamine (6-OHDA)-induced PD. The neuroprotective effects and levels of oxidative stress were evaluated after eight weeks of daily supplementation. Fecal microbiota composition was analyzed by fecal 16S rRNA gene sequencing. The supplements were associated with direct increases in host antioxidant enzyme activities and short-chain fatty acid production, protected dopaminergic neurons, and improved motor functions. The supplements also altered the fecal microbiota composition, and some specifically enriched commensal taxa correlated positively with superoxide dismutase, glutathione peroxidase, and catalase activity, indicating supplementation also promotes antioxidant activity via an indirect pathway. Therefore, L. salivarius AP-32 supplementation enhanced the activity of host antioxidant enzymes via direct and indirect modes of action in rats with 6-OHDA-induced PD.

PLA2G6 mutations cause motor dysfunction phenotypes of young-onset dystonia-parkinsonism type 14 and can be relieved by DHA treatment in animal models.

Parkinson's disease (PD), the most common neurodegenerative motor disorder, is currently incurable. Although many studies have provided insights on the substantial influence of genetic factors on the occurrence and development of PD, the molecular mechanism underlying the disease is largely unclear. Previous studies have shown that point mutations in the phospholipase A2 group VI gene (PLA2G6) correlate with young-onset dystonia-parkinsonism type 14 (PARK14). However, limited information is available regarding the pathogenic role of this gene and the mechanism underlying its function. To study the role of PLA2G6 mutations, we first used zebrafish larvae to screen six PLA2G6 mutations and revealed that injection of D331Y, T572I, and R741Q mutation constructs induced phenotypes such as motility defects and reduction in dopaminergic neurons. The motility defects could be alleviated by treatment with L-3, 4-dihydroxyphenylalanine (L-dopa), indicating that these mutations are pathological for PARK14 symptoms. Furthermore, the injection of D331Y and T572I mutation constructs reduced phospholipase activity of PLA2G6 and its lipid metabolites, which confirmed that these two mutations are loss-of-function mutations. Metabolomic analysis revealed that D331Y or T572I mutation led to higher phospholipid and lower docosahexaenoic acid (DHA) levels, indicating that reduced DHA levels are pathological for defective motor functions. Further, a dietary DHA supplement relieved the motility defects in PLA2G6D331Y/D331Y knock-in mice. This result revealed that the D331Y mutation caused defective PLA2G6 phospholipase activity and consequently reduced the DHA level, which is the pathogenic factor responsible for PARK14. The results of this study will facilitate the development of therapeutic strategies for PARK14.

Added Value of Rescue Devices in Intra-Arterial Thrombectomy: When Should We Apply Them?

Introduction: Recent trials have demonstrated the superior efficacy of mechanical thrombectomy over other medical treatments for acute ischemic stroke; however, not every large vessel occlusion (LVO) can be recanalized using a single thrombectomy device. Rescue devices were proved to increase the reperfusion rate, but the efficacy is unclear. Objective: In this retrospective study, we evaluated the efficacy of rescue therapy in different locations of LVO. Methods: We analyzed the outcomes of mechanical thrombectomy from a prospective registry of consecutive 82 patients in Taipei Medical University Hospital. The reperfusion rate and the functional outcome were compared in patients who received first-line therapy only and patients who need rescue therapy. Results: An 84.1% reperfusion rate was achieved in our cohort. We applied first-line stent retriever (SR) treatment in 6 patients, among which 4 (66.6%) achieved successful reperfusion. We applied a direct-aspiration first-pass technique (ADAPT) as the first-line treatment in 76 patients, among which 46 (60.5%) achieved successful reperfusion. Successful reperfusion could not be achieved in 30 cases (39.5%); therefore, we applied a second-line rescue SR for 28 patients, and reperfusion was established in 18 (64.3%) of them. These results revealed that the LVO in anterior circulation has a higher chance to respond to SR rescue therapy than posterior circulation lesions (68 vs. 33.3%, P < 0.001). Patients who received only first-line therapy exhibited significantly better functional outcomes than those who were also treated with rescue SR therapy (41.2 vs. 16.7%, P = 0.001). In addition, patients with LVO in the anterior circulation were found to have a higher probability of achieving functional independence than patients with posterior circulation lesions (10.7 vs. 0.0%, P < 0.001). The adjusted multivariate analysis revealed that successful reperfusion and treatment type (first-line or rescue therapy) were significantly related to a modified Rankin Scale (mRS) score at 90 days. Conclusion: This study reveals that rescue SR therapy improves the reperfusion rate. Patients who require rescue SR therapy have a lower likelihood of functional independence. LVO in the anterior circulation responds better to rescue SR therapy and results in better functional outcomes than posterior circulation lesions.

Functional variant rs17525453 within RAB35 gene promoter is possibly associated with increased risk of Parkinson's disease in Taiwanese population.

Our previous study suggests that upregulated RAB35 is implicated in etiology of Parkinson's disease (PD). We hypothesized that upregulated RAB35 results from single nucleotide polymorphisms (SNPs) in RAB35 gene promoter. We identified SNPs within RAB35 gene promoter by analyzing DNA samples of discovery cohort and validation cohort. SNP rs17525453 within RAB35 gene promoter (T>C at position of -66) was significantly associated with idiopathic PD patients. Compared to normal controls, sporadic PD patients had higher C allele frequency. CC and CT genotype significantly increased risk of PD compared with TT genotype. SNP rs17525453 within RAB35 gene promoter leads to formation of transcription factor TFII-I binding site. Results of EMSA and supershift assay indicated that TFII-I binds to rs17525453 sequence of RAB35 gene promoter. Luciferase reporter assays showed that rs17525453 variant of RAB35 gene promoter possesses an augmented transcriptional activity. Our results suggest that functional variant rs17525453 within RAB35 gene promoter is likely to enhance transcriptional activity and upregulate RAB35 protein, which could lead to increased risk of PD in Taiwanese population.

Probiotic Supplementation Facilitates Recovery of 6-OHDA-Induced Motor Deficit via Improving Mitochondrial Function and Energy Metabolism.

Parkinson's disease (PD) is a neurodegenerative disease associated with progressive impairment of motor and non-motor functions in aging people. Overwhelming evidence indicate that mitochondrial dysfunction is a central factor in PD pathophysiology, which impairs energy metabolism. While, several other studies have shown probiotic supplementations to improve host energy metabolism, alleviate the disease progression, prevent gut microbiota dysbiosis and alter commensal bacterial metabolites. But, whether probiotic and/or prebiotic supplementation can affect energy metabolism and cause the impediment of PD progression remains poorly characterized. Therefore, we investigated 8-weeks supplementation effects of probiotic [Lactobacillus salivarius subsp. salicinius AP-32 (AP-32)], residual medium (RM) obtained from the AP-32 culture medium, and combination of AP-32 and RM (A-RM) on unilateral 6-hydroxydopamine (6-OHDA)-induced PD rats. We found that AP-32, RM and A-RM supplementation induced neuroprotective effects on dopaminergic neurons along with improved motor functions in PD rats. These effects were accompanied by significant increases in mitochondrial activities in the brain and muscle, antioxidative enzymes level in serum, and altered SCFAs profile in fecal samples. Importantly, the AP-32 supplement restored muscle mass along with improved motor function in PD rats, and produced the best results among the supplements. Our results demonstrate that probiotic AP-32 and A-RM supplementations can recover energy metabolism via increasing SCFAs producing and mitochondria function. This restoring of mitochondrial function in the brain and muscles with improved energy metabolism might additionally be potentiated by ROS suppression by the elevated generation of antioxidants, and which finally leads to facilitated recovery of 6-OHDA-induced motor deficit. Taken together, this work demonstrates that probiotic AP-32 supplementation could be a potential candidate for alternate treatment strategy to avert PD progression.

EIF2AK2 Missense Variants Associated with Early Onset Generalized Dystonia.

OBJECTIVE: The study was undertaken to identify a monogenic cause of early onset, generalized dystonia. METHODS: Methods consisted of genome-wide linkage analysis, exome and Sanger sequencing, clinical neurological examination, brain magnetic resonance imaging, and protein expression studies in skin fibroblasts from patients. RESULTS: We identified a heterozygous variant, c.388G>A, p.Gly130Arg, in the eukaryotic translation initiation factor 2 alpha kinase 2 (EIF2AK2) gene, segregating with early onset isolated generalized dystonia in 5 patients of a Taiwanese family. EIF2AK2 sequencing in 191 unrelated patients with unexplained dystonia yielded 2 unrelated Caucasian patients with an identical heterozygous c.388G>A, p.Gly130Arg variant, occurring de novo in one case, another patient carrying a different heterozygous variant, c.413G>C, p.Gly138Ala, and one last patient, born from consanguineous parents, carrying a third, homozygous variant c.95A>C, p.Asn32Thr. These 3 missense variants are absent from gnomAD, and are located in functional domains of the encoded protein. In 3 patients, additional neurological manifestations were present, including intellectual disability and spasticity. EIF2AK2 encodes a kinase (protein kinase R [PKR]) that phosphorylates eukaryotic translation initiation factor 2 alpha (eIF2α), which orchestrates the cellular stress response. Our expression studies showed abnormally enhanced activation of the cellular stress response, monitored by PKR-mediated phosphorylation of eIF2α, in fibroblasts from patients with EIF2AK2 variants. Intriguingly, PKR can also be regulated by PRKRA (protein interferon-inducible double-stranded RNA-dependent protein kinase activator A), the product of another gene causing monogenic dystonia. INTERPRETATION: We identified EIF2AK2 variants implicated in early onset generalized dystonia, which can be dominantly or recessively inherited, or occur de novo. Our findings provide direct evidence for a key role of a dysfunctional eIF2α pathway in the pathogenesis of dystonia. ANN NEUROL 2021;89:485-497.

(D620N) VPS35 causes the impairment of Wnt/ß-catenin signaling cascade and mitochondrial dysfunction in a PARK17 knockin mouse model.

Patients with familial type 17 of Parkinson's disease (PARK17) manifest autosomal dominant pattern and late-onset parkinsonian syndromes. Heterozygous (D620N) mutation of vacuolar protein sorting 35 (VPS35) is genetic cause of PARK17. We prepared heterozygous VPS35D620N/+ knockin mouse, which is an ideal animal model of (D620N) VPS35-induced autosomal dominant PARK17. Late-onset loss of substantia nigra pars compacta (SNpc) dopaminergic (DAergic) neurons and motor deficits of Parkinson's disease were found in 16-month-old VPS35D620N/+ mice. Normal function of VPS35-containing retromer is needed for activity of Wnt/ß-catenin cascade, which participates in protection and survival of SNpc DAergic neurons. It was hypothesized that (D620N) VPS35 mutation causes the malfunction of VPS35 and resulting impaired activity of Wnt/ß-catenin pathway. Protein levels of Wnt1 and nuclear ß-catenin were reduced in SN of 16-month-old VPS35D620N/+ knockin mice. Downregulated protein expression of survivin, which is a target gene of nuclear ß-catenin, and upregulated protein levels of active caspase-8 and active caspase-9 were observed in SN of VPS35D620N/+ mice at age of 16 months. VPS35 is involved in controlling morphology and function of mitochondria. Impaired function of VPS35 caused by (D620N) mutation could lead to abnormal morphology and malfunction of mitochondria. A significant decrease in mitochondrial size and resulting mitochondrial fragmentation was found in tyrosine hydroxylase-positive and neuromelanin-positive SNpc DAergic neurons of 16-month-old VPS35D620N/+ mice. Mitochondrial complex I activity or complex IV activity was reduced in SN of 16-month-old VPS35D620N/+ mice. Increased level of mitochondrial ROS and oxidative stress were found in SN of 16-month-old VPS35D620N/+ mice. Levels of cytosolic cytochrome c and active caspase-3 were increased in SN of VPS35D620N/+ mice aged 16 months. Our results suggest that PARK17 mutant (D620N) VPS35 impairs activity of Wnt/ß-catenin signaling pathway and causes abnormal morphology and dysfunction of mitochondria, which could lead to neurodegeneration of SNpc DAergic cells.

Alda-1, an activator of ALDH2, ameliorates Achilles tendinopathy in cellular and mouse models.

Achilles tendinopathy has a high re-injury rate and poor prognosis. Development of effective therapy for Achilles tendinopathy is important. Excessive accumulation of ROS and resulting oxidative stress are believed to cause tendinopathy. Overproduction of hydrogen peroxide (H2O2), the most common ROS, could lead to the tendinopathy by causing oxidative damage, activation of endoplasmic reticulum (ER) stress and apoptotic death of tenocytes. Activation of mitochondrial aldehyde dehydrogenase 2 (ALDH2) is expected to alleviate oxidative stress and ER stress. Alda-1 is a selective and potent activator of ALDH2. In this study, we examined the cytoprotective benefit of Alda-1, an activator of ALDH2, on H2O2-induced Achilles tendinopathy in cellular and mouse models. We prepared cellular and mouse models of Achilles tendinopathy by treating cultured Achilles tenocytes and Achilles tendons with oxidative stressor H2O2. Subsequently, we studied the protective benefit of Alda-1 on H2O2-induced Achilles tendinopathy. Alda-1 pretreatment attenuated H2O2-induced cell death of cultured Achilles tenocytes. Treatment of Alda-1 prevented H2O2-induced oxidative stress and depolarization of mitochondrial membrane potential in tenocytes. Application of Alda-1 attenuated H2O2-triggered mitochondria- and ER stress-mediated apoptotic cascades in cultured tenocytes. Alda-1 treatment ameliorated the severity of H2O2-induced Achilles tendinopathy in vivo by preventing H2O2-induced pathological histological features of Achilles tendons, apoptotic death of Achilles tenocytes and upregulated expression of inflammatory cytokines IL-1ß and TNF-α. Our results provide the evidence that ALDH2 activator Alda-1 ameliorates H2O2-induced Achilles tendinopathy. Alda-1 could be used for preventing and treating Achilles tendinopathy.

Upregulated Expression of MicroRNA-204-5p Leads to the Death of Dopaminergic Cells by Targeting DYRK1A-Mediated Apoptotic Signaling Cascade.

MicroRNAs (miRs) downregulate or upregulate the mRNA level by binding to the 3'-untranslated region (3'UTR) of target gene. Dysregulated miR levels can be used as biomarkers of Parkinson's disease (PD) and could participate in the etiology of PD. In the present study, 45 brain-enriched miRs were evaluated in serum samples from 50 normal subjects and 50 sporadic PD patients. The level of miR-204-5p was upregulated in serum samples from PD patients. An upregulated level of miR-204-5p was also observed in the serum and substantia nigra (SN) of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of PD. Expression of miR-204-5p increased the level of α-synuclein (α-Syn), phosphorylated (phospho)-α-Syn, tau, or phospho-tau protein and resulted in the activation of endoplasmic reticulum (ER) stress in SH-SY5Y dopaminergic cells. Expression of miR-204-5p caused autophagy impairment and activation of c-Jun N-terminal kinase (JNK)-mediated apoptotic cascade in SH-SY5Y dopaminergic cells. Our study using the bioinformatic method and dual-luciferase reporter analysis suggests that miR-204-5p positively regulates mRNA expression of dual-specificity tyrosine phosphorylation regulated kinase 1A (DYRK1A) by directly interacting with 3'UTR of DYRK1A. The mRNA and protein levels of DYRK1A were increased in SH-SY5Y dopaminergic cells expressing miR-204-5p and SN of MPTP-induced PD mouse model. Knockdown of DYRK1A expression or treatment of the DYRK1A inhibitor harmine attenuated miR-204-5p-induced increase in protein expression of phospho-α-Syn or phospho-tau, ER stress, autophagy impairment, and activation of JNK-mediated apoptotic pathway in SH-SY5Y dopaminergic cells or primary cultured dopaminergic neurons. Our results suggest that upregulated expression of miR-204-5p leads to the death of dopaminergic cells by targeting DYRK1A-mediated ER stress and apoptotic signaling cascade.

Combined Assessment of Serum Alpha-Synuclein and Rab35 is a Better Biomarker for Parkinson's Disease.

BACKGROUND AND PURPOSE: It is essential to develop a reliable predictive serum biomarker for Parkinson's disease (PD). The accumulation of alpha-synuclein (αSyn) and up-regulated expression of Rab35 participate in the etiology of PD. The purpose of this investigation was to determine whether the combined assessment of serum αSyn and Rab35 is a useful predictive biomarker for PD. METHODS: Serum levels of αSyn or Rab35 were determined in serum samples from 59 sporadic PD patients, 19 progressive supranuclear palsy (PSP) patients, 20 multiple system atrophy (MSA) patients, and 60 normal controls (NC). Receiver operating characteristics (ROC) curves were calculated to determine the diagnostic accuracy of αSyn or/and Rab35 in discriminating PD patients from NC or atypical parkinsonian patients. RESULTS: The levels of αSyn and Rab35 were increased in PD patients. The serum level of Rab35 was positively correlated with that of αSyn in PD patients. Compared to analyzing αSyn or Rab35 alone, the combined analysis of αSyn and Rab35 produced a larger area under the ROC curve and performed better in discriminating PD patients from NC, MSA patients, or PSP patients. When age was dichotomized at 55, 60, 65, or 70 years, the combined assessment of αSyn and Rab35 for classifying PD was better in the group below the cutoff age than in the group above the cutoff age. CONCLUSIONS: Combined assessment of serum αSyn and Rab35 is a better biomarker for discriminating PD patients from NC or atypical parkinsonian patients, and is a useful predictive biomarker for younger sporadic PD patients.

Generation of induced pluripotent stem cells from a young-onset Parkinson's disease patient carrying the compound heterozygous PLA2G6 p.D331Y/p.M358IfsX mutations.

Mutations in PLA2G6 gene cause PLA2G6-associated neurodegeneration, including recessive familial type 14 of Parkinson's disease (PARK14). Previously, we identified PARK14 patients with compound heterozygous c.991G > T/c.1077G > A (p.D331Y/p.M358IfsX) mutations. The c.1077G > A mutation led to a four base-pairs deletion and frameshift mutation (p.M358IfsX) of PLA2G6 mRNA. We established induced pluripotent stem cells (iPSCs) from peripheral blood mononuclear cells of a female patient with compound heterozygous c.991G > T/c.1077G > A (p.D331Y/ p.M358IfsX) mutations by using Sendai-virus delivery system. The iPSCs exhibited pluripotency and in vivo differentiation potential. The iPSCs can be used for studying the molecular pathogenic mechanism of PARK14.

The Occurrence of Metronidazole-Induced Encephalopathy in Cancer Patients: A Hospital-Based Retrospective Study.

BACKGROUND: Metronidazole-induced encephalopathy (MIE) is a rare but serious complication caused by metronidazole, a widely used antianaerobic drug. Previous studies prescribed MIE including dysarthria, cerebellar ataxia, and confusion after long-term use of metronidazole. Malignancy has been proposed one of the predisposing conditions for MIE. However, the occurrence of MIE in cancer patients remains unknown. METHODOLOGY: We investigated the occurrence of MIE and analyzed retrospectively by hospital-based data of 4160 cancer patients from January 2014 to December 2016. RESULTS: Findings in 793 cancer patients who underwent metronidazole therapy for anaerobic infection revealed two cases of MIE. One had renal cell carcinoma and the other had bladder urothelial carcinoma. Both of their initial presentation were cerebellar dysfunction. The occurrence of MIE was 8.6% for cases who received >30 g of cumulative dose. Hypertension was the most common comorbidity, followed by chronic renal disease and diabetes mellitus. CONCLUSION: In cancer patients, MIE should be monitored in those with genitourinary cancer, especially with renal dysfunction. Longer duration with more cumulative dose also has a greater risk of MIE. Early consideration of MIE with prompt cessation of metronidazole may result in better outcome.

Association of Antiviral Therapy With Risk of Parkinson Disease in Patients With Chronic Hepatitis C Virus Infection.

IMPORTANCE: Epidemiologic evidence suggests that hepatitis C virus (HCV) could be a risk factor for Parkinson disease (PD), but treatment for HCV infection has never been considered in these studies; hence, the association between antiviral therapy and PD incidence has remained unclear. Understanding this association may help in developing strategies to reduce PD occurrence. OBJECTIVE: To identify the risk of PD development in patients with HCV infection receiving antiviral treatment and in patients not receiving this treatment. DESIGN, SETTING, AND PARTICIPANTS: This cohort study obtained claims data from the Taiwan National Health Insurance Research Database. Adult patients with a new HCV diagnosis with or without hepatitis per International Classification of Diseases, Ninth Revision, Clinical Modification codes and anti-PD medications from January 1, 2003, to December 31, 2013, were selected for inclusion. After excluding participants not eligible for analysis, the remaining patients (n = 188 152) were categorized into treated and untreated groups according to whether they received antiviral therapy. Propensity score matching was performed to balance the covariates across groups for comparison of main outcomes. This study was conducted from July 1, 2017, to December 31, 2017. MAIN OUTCOMES AND MEASURES: Development of PD was the main outcome. A Cox proportional hazards regression model was used to compare the risk of PD, and the hazard ratio (HR) was calculated at 1 year, 3 years, and 5 years after the index date and at the end of the cohort. RESULTS: A total of 188 152 patients were included in the analysis. An equal number (n = 39 936) and comparable characteristics of participants were retained in the treated group (with 17 970 female [45.0%] and a mean [SD] age of 52.8 [11.4] years) and untreated group (with 17 725 female [44.4%] and a mean [SD] age of 52.5 [12.9] years) after matching. The incidence density of PD was 1.00 (95% CI, 0.85-1.15) in the treated group and 1.39 (95% CI, 1.21-1.57) per 1000 person-years in the untreated group. The advantage of antiviral therapy reached statistical significance at the 5-year follow-up (HR, 0.75; 95% CI, 0.59-0.96), and this advantage continued to increase until the end of follow-up (HR, 0.71; 95% CI, 0.58-0.87). CONCLUSIONS AND RELEVANCE: Evidence suggested that the PD incidence was lower in patients with chronic HCV infection who received interferon-based antiviral therapy; this finding may support the hypothesis that HCV could be a risk factor for PD.

PARK14 (D331Y) PLA2G6 Causes Early-Onset Degeneration of Substantia Nigra Dopaminergic Neurons by Inducing Mitochondrial Dysfunction, ER Stress, Mitophagy Impairment and Transcriptional Dysregulation in a Knockin Mouse Model.

PARK14 patients with homozygous (D331Y) PLA2G6 mutation display motor deficits of pure early-onset Parkinson's disease (PD). The aim of this study is to investigate the pathogenic mechanism of mutant (D331Y) PLA2G6-induced PD. We generated knockin (KI) mouse model of PARK14 harboring homozygous (D331Y) PLA2G6 mutation. Then, we investigated neuropathological and neurological phenotypes of PLA2G6D331Y/D331Y KI mice and molecular pathogenic mechanisms of (D331Y) PLA2G6-induced degeneration of substantia nigra (SN) dopaminergic neurons. Six-or nine-month-old PLA2G6D331Y/D331Y KI mice displayed early-onset cell death of SNpc dopaminergic neurons. Lewy body pathology was found in the SN of PLA2G6D331Y/D331Y mice. Six-or nine-month-old PLA2G6D331Y/D331Y KI mice exhibited early-onset parkinsonism phenotypes. Disrupted cristae of mitochondria were found in SNpc dopaminergic neurons of PLA2G6D331Y/D331Y mice. PLA2G6D331Y/D331Y mice displayed mitochondrial dysfunction and upregulated ROS production, which may lead to activation of apoptotic cascade. Upregulated protein levels of Grp78, IRE1, PERK, and CHOP, which are involved in activation of ER stress, were found in the SN of PLA2G6D331Y/D331Y mice. Protein expression of mitophagic proteins, including parkin and BNIP3, was downregulated in the SN of PLA2G6D331Y/D331Y mice, suggesting that (D331Y) PLA2G6 mutation causes mitophagy dysfunction. In the SN of PLA2G6D331Y/D331Y mice, mRNA levels of eight genes that are involved in neuroprotection/neurogenesis were decreased, while mRNA levels of two genes that promote apoptotic death were increased. Our results suggest that PARK14 (D331Y) PLA2G6 mutation causes degeneration of SNpc dopaminergic neurons by causing mitochondrial dysfunction, elevated ER stress, mitophagy impairment, and transcriptional abnormality.

Serum lipid level is not associated with symptomatic intracerebral hemorrhage after intravenous thrombolysis for acute ischemic stroke.

BACKGROUND: This study assessed whether serum lipid levels are associated with the risk of symptomatic intracerebral hemorrhage (sICH) and functional outcomes in patients with acute ischemic stroke after receiving intravenous thrombolysis. METHODS: We retrospectively analyzed consecutive ischemic stroke patients who were treated with intravenous tissue plasminogen activator between January 2007 and January 2017. Lipid levels on admission, including total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglyceride levels, as well as potential predictors of sICH were tested using univariate and multivariate analyses. RESULTS: Of the 229 enrolled patients (100 women, aged 68 ± 13 years), 14 developed sICH and 103 (45%) had favorable functional outcomes at 3 months. The patients with sICH more often had diabetes mellitus (71% vs. 26%, P = 0.01) and had more severe stroke (mean National Institutes of Health Stroke Scale [NIHSS] score of 16 vs. 13, P = 0.045). Regarding lipid subtype, total cholesterol, LDL-C, HDL-C, and triglyceride levels were not associated with sICH or functional outcomes. According to the results of multivariate analysis, the frequency of sICH was independently associated with diabetes mellitus (odds ratio [OR] = 6.04; 95% CI [1.31-27.95]; P = 0.02) and the NIHSS score (OR = 1.12; 95% CI [1.02-1.22]; P = 0.01). A higher NIHSS score was independently associated with unfavorable functional outcomes (OR = 0.86; 95% CI [0.81-0.91]; P < 0.001). CONCLUSIONS: Serum lipid levels on admission, including total cholesterol, LDL-C, HDL-C, and triglyceride levels, were not associated with sICH or 3-month functional outcomes after intravenous thrombolysis for acute ischemic stroke.