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.

Effects of Yoga for Coping with Premenstrual Symptoms in Taiwan-A Cluster Randomized Study.

Home-based yoga practice has not been approved as a method for alleviating premenstrual symptoms in Taiwan. This study was a cluster randomized trial. A total of 128 women self-reporting at least one premenstrual symptom were enrolled in the study, of which there were 65 participants in the experimental group and 63 participants in the control group. Women in the yoga group were provided with a yoga DVD program (30 min) to practice for three menstrual months, at least three times a week. All participants were given the Daily Record of Severity of Problems (DRSP) form to measure premenstrual symptoms. After the yoga exercise intervention, the yoga group had statistically significantly fewer and/or less severe premenstrual depressive symptoms, physical symptoms, and anger/irritability. Other disturbances and the impairment of daily routine, hobbies/social activities, and relationships also occurred significantly less often in the yoga group. The study found that yoga is useful to relieve premenstrual symptoms. Moreover, home-based yoga practice is more pertinent in the pandemic era. The strengths and drawbacks of the study are discussed and further study is recommended.

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.

Identification of the Time Period during Which BMP Signaling Regulates Proliferation of Neural Progenitor Cells in Zebrafish.

Bone morphogenetic protein (BMP) signaling regulates neural induction, neuronal specification, and neuronal differentiation. However, the role of BMP signaling in neural progenitors remains unclear. This is because interruption of BMP signaling before or during neural induction causes severe effects on subsequent neural developmental processes. To examine the role of BMP signaling in the development of neural progenitors in zebrafish, we bypassed the effect of BMP signaling on neural induction and suppressed BMP signaling at different time points during gastrulation using a temporally controlled transgenic line carrying a dominant-negative form of Bmp receptor type 1aa and a chemical inhibitor of BMP signaling, DMH1. Inhibiting BMP signaling from 8 hpf could bypass BMP regulation on neural induction, induce the number of proliferating neural progenitors, and reduce the number of neuronal precursors. Inhibiting BMP signaling upregulates the expression of the Notch downstream gene hairy/E(spl)-related 2 (her2). Inhibiting Notch signaling or knocking down the Her2 function reduced neural progenitor proliferation, whereas inactivating BMP signaling in Notch-Her2 deficient background restored the number of proliferating neural progenitors. These results reveal the time window for the proliferation of neural progenitors during zebrafish development and a fine balance between BMP and Notch signaling in regulating the proliferation of neural progenitor cells.

Exploring Perceived Stress in Mothers with Singleton and Multiple Preterm Infants: A Cross-Sectional Study in Taiwan.

OBJECTIVE: The aim of this study was to explore mothers' perceived level of stress one month after hospital discharge following the birth of singleton and multiple preterm infants. DESIGN: A cross-sectional design was used to compare mother's perceived stress in two groups of postpartum mothers and the relationship of the theoretical antecedents and these variables. SETTING: A neonatal intensive care unit in a medical center in Taiwan. PARTICIPANTS: Mothers of 52 singletons and 38 multiple premature infants were recruited. One month after the infant was discharged, the participants completed a self-reported questionnaire that included demographic data about the mother and infant, the 21-item Social Support Scale, and the 15-item Perceived Stress Scale. This was returned by email or completed at the outpatient unit. ANALYSIS: Descriptive and inferential analysis. RESULTS: The mean social support scores were 76.6 and 76.5 (out of 105) for mothers with singleton and multiple birth infants, respectively. The most important supporter was the husband. The mean perceived stress scores of 25.8 and 31.0 for mothers with singleton and multiple birth infants, respectively, were significantly different (p = 0.02). Sleep deprivation and social support were predictive indicators of perceived stress in mothers with preterm infants. CONCLUSIONS: We suggest that the differences in stress and needs of mothers with singleton and multiple births should be recognized and addressed in clinics. The findings of this study serve as a reference for promoting better preterm infant care.

Enhanced Virulence of Candida albicans by Staphylococcus aureus: Evidence in Clinical Bloodstream Infections and Infected Zebrafish Embryos.

Coinfection with Candida and Staphylococcus results in higher mortality in animal studies. However, the pathogenesis and interplay between C. albicans and S. aureus in bloodstream infections (BSIs) is unclear. This study determines the clinical features and outcomes of mixed C. albicans/S. aureus (CA/SA) BSIs and biofilm formation on pathogenesis during coinfection. Demographics and outcomes for mixed BSIs and monomicrobial candidemia were compared. Compared to 115 monomicrobial C. albicans BSIs, 22 patients with mixed CA/SA BSIs exhibited a significantly higher mortality rate and shorter survival time. In vitro and in vivo biofilm analysis showed that C. albicans accounted for the main biofilm architecture, and S. aureus increased its amount. Antibiotic tolerance in S. aureus, which adhered to Candida hyphae observed by scanning electron microscope, was demonstrated by the presence of wild-type C. albicans co-biofilm. Upregulation in exotoxin genes of S. aureus was evidenced by quantitative RT-PCR when a co-biofilm was formed with C. albicans. Mixed CA/SA BSIs result in a higher mortality rate in patients and in vivo surrogate models experiments. This study demonstrates that the virulence enhancement of C. albicans and S. aureus during co-biofilm formation contributes to the high mortality rate.

RGS2 Suppresses Melanoma Growth via Inhibiting MAPK and AKT Signaling Pathways.

BACKGROUND/AIM: This study aimed to explore RGS2 as a regulator of melanoma cell growth. MATERIALS AND METHODS: Effect of RGS2 over-expression was analyzed in three melanoma cell lines, and Rgs2 knockdown was performed in zebrafish. RESULTS: RGS2 was differentially expressed among the cell lines. In B16F10 cells, RGS2 over-expression inhibited MAPK and AKT activation, and prevented cell growth. A similar outcome was observed in A375 cells, but the MAPK signals were not suppressed. In A2058 cells, RGS2 repressed AKT activation, but without affecting cell growth. Moreover, MAPK and AKT constitutive activation abolished the RGS2 inhibitory effect on B16F10 cell growth. Rgs2 knockdown caused ectopic melanocyte differentiation, and promoted MAPK and AKT activation in zebrafish embryos. CONCLUSION: RGS2 prevents melanoma cell growth by inhibiting MAPK and AKT, but this effect depends on the overall cell genetic landscape. Further studies are warranted to investigate the anticancer therapeutic potential of RGS2 for melanoma.

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.

A fourfold interpenetrating three-dimensional cadmium(II) coordination polymer: synthesis, crystal structure and physical properties.

A novel three-dimensional CdII coordination framework, namely, poly[{µ-bis[4-(2-methylimidazol-1-yl)phenyl] ether-κ2N3:N3'}(µ-naphthalene-1,4-dicarboxylato-κ3O1:O4,O4')cadmium(II)], [Cd(C12H6O4)(C20H18N4O)]n or [Cd(1,4-NDC)(BMIOPE)]n, where 1,4-H2NDC is naphthalene-1,4-dicarboxylic acid and BMIOPE is bis[4-(2-methylimidazol-1-yl)phenyl] ether, has been prepared and characterized by single-crystal X-ray diffraction, elemental analysis, IR spectroscopy and thermogravimetric analysis. The compound displays a novel fourfold interpenetrating diamond-like network. In addition, it not only shows a strong fluorescence emission in the solid state, but also exhibits excellent photocatalytic activity for the degradation of methylene blue (MB) at room temperature.

Association between CAI microsatellite, multilocus sequence typing, and clinical significance within Candida albicans isolates.

Candida albicans bloodstream infection (BSI) is epidemiologically important because of its increasing frequency and serious outcome. Strain typing and delineation of the species are essential for understanding the phylogenetic relationship and clinical significance. Microsatellite CAI genotyping and multilocus sequence typing (MLST) were performed on 285 C. albicans bloodstream isolates from patients in Chang Gung Memorial Hospital at Linkou (CGMHL), Taiwan from 2003 to 2011. Data regarding demographics, comorbidities, risk factors, and clinical outcomes were recorded within adult patients with C. albicans BSI. Both CAI genotyping and MLST yielded comparable discriminatory power for C. albicans characterization. Besides, the distribution of CAI repetition showed a satisfactory phylogenetic association, which could be a good alternative method in the molecular phylogenetics of C. albicans and epidemiological studies. As for the clinical scenario, clade 17 isolates with CAI alleles either possessing 29 or more repetitions were related to higher 14-day and 30-day mortality, and shorter median survival days.

Experiential Learning Program to Strengthen Self-Reflection and Critical Thinking in Freshmen Nursing Students during COVID-19: A Quasi-Experimental Study.

This article focuses on the unique needs and concerns of nursing educators and nursing students in the face of the COVID-19 pandemic. During social distancing, interacting with other human beings has been restricted. This would undermine the experiential learning of nursing students. Hence, it is important to develop and evaluate an experiential learning program (ELP) for nursing education. A pre-test and post-test design were used. The study was conducted in a university in Central Taiwan. A total of 103 nursing students participated in the study from February to June 2019. The study intervention was the experiential learning program (ELP), including bodily experiences and nursing activities with babies, pregnant women, and the elderly. After the intervention, the students completed the self-reflection and insight scale (SRIS) and Taiwan Critical Thinking Disposition Inventory (TCTDI) as outcome measures. An independent t-test showed that there was a significant difference between pre-test and post-test in both SRIS and TCTDI (p < 0.01). The Pearson product-moment correlation analysis showed that SRIS and TCTDI were significantly positively correlated (p < 0.01). ELP has a significant impact on the self-reflection and critical thinking of first-year nursing students, which can be used as a reference for the education of nursing students. During these turbulent times, it is especially vital for faculties to provide experiential learning instead of the traditional teaching concept.

Nanogold Neuroprotection in Human Neural Stem Cells Against Amyloid-beta-induced Mitochondrial Dysfunction.

Alzheimer's disease (AD) is a neuronal dementia with progressive memory loss. Amyloid-beta (Aß) peptides has major effect in the neurodegenerative disorder, which are thought to promote mitochondrial dysfunction in AD brains. Anti-AD drugs acting upon the brain are generally difficult to develop, often cause serious side effects or lack therapeutic efficacy. Numerous studies have shown the beneficial therapeutic applications of gold nanoparticles (AuNPs), including for neuroprotective events and AD. The aim of this study is to understand how AuNPs could exert their neuroprotective role in AD, for which cell model have chosen human neural stem cells (hNSCs) as the experimental tool. We hypothesize AuNPs protect against Aß-induced cellular impairment and mitochondrial dysfunction in hNSCs. Here, we show AuNPs increase the survival of hNSCs treated with Aß via downregulation of caspase 3 and 9 activities. Moreover, AuNPs abrogated the Aß-mediated decrease neuroprotective (CREB and Bcl-2) and mitochondrial (PGC1α, NRF-1 and Tfam) gene expressions in treated hNSCs. Importantly, co-treatment with AuNPs significantly rescued hNSCs from Aß-mediated mitochondrial function and morphology. AuNPs also significantly normalizes the immunostaining of mitochondrial marker and mass in differentiated hNSCs with Aß. The effects may be exerted by the AuNPs, as supported by its protective reversal of Aß-induced cellular impairment and mitochondrial dysfunction in hNSCs. In fact, the results presented extend our understanding of the mechanisms through which AuNPs could exert their neuroprotective role in hNSCs treated with Aß.

Neuroprotective effects of resveratrol against oxygen glucose deprivation induced mitochondrial dysfunction by activation of AMPK in SH-SY5Y cells with 3D gelatin scaffold.

Ischemic stroke arising from the sudden blockage of arteries in the brain, is a common and serious brain damaging problem worldwide, often leading to disability or death. The oxygen glucose deprivation (OGD) model was created to improve understanding of hypoxia- and hypoglycemia-induced neuronal cell injury, and provide an in vitro surrogate to assess novel treatments for cerebral hypoxia-ischemia. AMP-activated protein kinase (AMPK) is a critical neuroprotective regulator of energy homeostasis, metabolism and cell survival. However, the neuroprotective mechanisms by which AMPK achieves these beneficial effects in human SH-SY5Y neural cells exposed to OGD are still not well understood. Resveratrol is a potent activator of AMPK suggesting it may have therapeutic potential as a neuroprotective agent. Therefore, we hypothesized the AMPK activator resveratrol protects against OGD-mediated impairment of human SH-SY5Y neuronal cells. The novelty of the experiment using a 3D gelatin scaffold cell culture assay, we have tested the potential of 3D systems to mimic the endogenous neuronal environment and have applied these systems to study the effect of OGD on neuronal cells with/without resveratrol. Here we show resveratrol reverses, via AMPK-dependent downregulation of caspase 3 and 9 activity, the OGD-mediated decreases in SH-SY5Y cell viability on a 3D gelatin scaffold. In addition, treatment with OGD decreases mRNA levels of AMPK and the neuroprotective genes (Bcl-2 and CREB); however, co-treatment with resveratrol significantly normalizes these effects. Importantly, resveratrol improves the expression of AMPK and p-AMPK in OGD-exposed SH-SY5Y cells. Resveratrol also significantly rescues SH-SY5Y cells from OGD-mediated mitochondrial deficiency (lower D-loop level, mitochondrial mass, maximal respiratory function, COX activity, and mitochondrial membrane potential). Resveratrol also rescues the transcript expression levels of PGC1α and mitochondrial genes (NRF-1 and Tfam) in OGD-treated SH-SY5Y cells. These findings extend our mechanistic understanding of the central role of AMPK in OGD-related neuronal impairment, and may serve as basis for implementing new therapeutic strategies in the treatment of ischemic stroke.

Fungicidal and anti-biofilm activities of trimethylchitosan-stabilized silver nanoparticles against Candida species in zebrafish embryos.

Herein, positively surface-charged silver nanoparticles (AgNPs) capped with trimethylchitosan nitrate (TMCN) were synthesized using an environmentally friendly method. Nano-sized TMCN-AgNPs (~80 nm) with high zeta potential (>30 mV) provide sufficient static repulsion to stabilize colloid AgNPs in aqueous solutions without aggregation for >3 months. In in vitro cell cycle assays, TMCN-AgNPs showed low cytotoxicity towards L929 cells. A microdilution inhibition assay demonstrated the antifungal potential of TMCN-AgNPs, with a minimum inhibitory concentration of 0.06 mM against Candida tropicalis ATCC 750, and 0.46 mM against both Candida albicans ATCC 76615 and Candida glabrata ATCC 15545. Moreover, the addition of TMCN-AgNPs at 0.23 mM significantly reduced biofilm formation in 96-well plates with C. albicans and C. tropicalis. Importantly, when zebrafish eggs were infected with Candida cells, 0.23 mM TMCN-AgNPs greatly diminished the amount of biofilm on eggs and rescued the survival of embryos by up to 70%.

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.

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.

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.

DDX3 Participates in Translational Control of Inflammation Induced by Infections and Injuries.

Recent studies have suggested that DDX3 functions in antiviral innate immunity, but the underlying mechanism remains elusive. We previously identified target mRNAs whose translation is controlled by DDX3. Pathway enrichment analysis of these targets indicated that DDX3 is involved in various infections and inflammation. Using immunoblotting, we confirmed that PACT, STAT1, GNB2, Rac1, TAK1, and p38 mitogen-activated protein kinase (MAPK) proteins are downregulated by DDX3 knockdown in human monocytic THP-1 cells and epithelial HeLa cells. Polysome profiling revealed that DDX3 knockdown reduces the translational efficiency of target mRNAs. We further demonstrated DDX3-mediated translational control of target mRNAs by luciferase reporter assays. To examine the effects of DDX3 knockdown on macrophage migration and phagocytosis, we performed in vitro cell migration assay and flow cytometry analysis of the uptake of green fluorescent protein-expressing Escherichia coli in THP-1 cells. The DDX3 knockdown cells exhibited impaired macrophage migration and phagocytosis. Moreover, we used a human cytokine antibody array to identify the cytokines affected by DDX3 knockdown. Several chemokines were decreased considerably in DDX3 knockdown THP-1 cells after lipopolysaccharide or poly(I·C) stimulation. Lastly, we demonstrated that DDX3 is crucial for the recruitment of phagocytes to the site of inflammation in transgenic zebrafish.

Pparα deficiency inhibits the proliferation of neuronal and glial precursors in the zebrafish central nervous system.

BACKGROUND: Many molecules and signaling pathways involved in neural development play a role in neurodegenerative diseases and brain tumor progression. Peroxisome proliferator-activated receptor (PPAR) proteins regulate the differentiation of tissues and the progression of many diseases. However, the role of these proteins in neural development is unclear. RESULTS: We examined the function of Pparα in the neural development of zebrafish. Two duplicate paralogs for mammalian PPARA/Ppara, namely pparaa and pparab, are present in the zebrafish genome. Both pparaa and pparab are expressed in the developing central nervous system in zebrafish embryos. Inhibiting the function of Pparα by using either the PPARα/Pparα antagonist GW6471 or pparaa or pparab truncated constructs produced identical phenotypes, which were sufficient to reduce the proliferation of neuronal and glial precursor cells without affecting the formation of neural progenitors. CONCLUSIONS: We demonstrated that both Pparαa and Pparαb proteins are essential regulators of the proliferation of neuronal and glial precursors. This study provides a better understanding of the functions of PPARα/Pparα in neural development and further expands our knowledge of the potential role of PPARα/Pparα in neurological disorders and brain tumors. Developmental Dynamics 247:1264-1275, 2018. © 2018 Wiley Periodicals, Inc.

Rosiglitazone rescues human neural stem cells from amyloid-beta induced ER stress via PPARγ dependent signaling.

Peroxisome proliferator-activated receptor gamma (PPARγ) belongs to a family of ligand-activated nuclear receptors known to regulate many crucial physiological and pathological conditions. Indeed, altered PPARγ transcriptional activity contributes to metabolic syndromes (obesity and hyperglycemia associated with type 2 diabetes mellitus), stroke and neurodegenerative diseases. Various studies suggest that PPARγ agonists influence neuronal deficits in Alzheimer's Disease (AD) patients and rodent models of AD. Expression of amyloid-beta (Aß), a neuropathological marker associated with the pathogenesis of AD neuronal impairment, is inversely correlated with the activation of PPARγ-dependent neuroprotective responses. Nevertheless, molecular mechanisms by which the effects of PPARγ agonists in AD remain to be clarified. Here, we explore the PPARγ signaling pathways and networks that protect against Aß-induced endoplasmic reticulum (ER) stress (e.g., caspase 4, Bip, CHOP, ASK1 and ER calcium), cell death (e.g., viability and cytochrome c) and mitochondrial deficiency (e.g., maximal respiratory function, COX activity, and mitochondrial membrane potential) events in the human neural stem cells (hNSCs) treated with Aß. Co-treatment with GW9662 (an antagonist of PPARγ) effectively blocked these protective effects by rosiglitazone, providing strong evidence that PPARγ-dependent signaling rescues hNSCs from Aß-mediated toxicity. Together, our data suggest activation of PPARγ pathway might be critical to protecting against AD-related ER stress, ER disequilibrium and mitochondrial deficiency. These findings also improve our understanding of the role of PPARγ in hNSCs, and may aid in the development and implementation of new therapeutic strategies for the treatment of AD.