Isorhamnetin Attenuated the Release of Interleukin-6 from ß-Amyloid-Activated Microglia and Mitigated Interleukin-6-Mediated Neurotoxicity.

Alzheimer's disease (AD), characterized by the abnormal accumulation of ß-amyloid (Aß), is the most prevalent type of dementia, and it is associated with progressive cognitive decline and memory loss. Aß accumulation activates microglia, which secrete proinflammatory factors associated with Aß clearance impairment and cause neurotoxicity, generating a vicious cycle among Aß accumulation, activated microglia, and proinflammatory factors. Blocking this cycle can be a therapeutic strategy for AD. Using Aß-activated HMC3 microglial cells, we observed that isorhamnetin, a main constituent of Oenanthe javanica, reduced the Aß-triggered secretion of interleukin- (IL-) 6 and downregulated the expression levels of the microglial activation markers ionized calcium binding adaptor molecule 1 (IBA1) and CD11b and the inflammatory marker nuclear factor-κB (NF-κB). Treatment of the SH-SY5Y-derived neuronal cells with the Aß-activated HMC3-conditioned medium (HMC3-conditioned medium) or IL-6 increased reactive oxygen species production, upregulated cleaved caspase 3 expression, and reduced neurite outgrowth, whereas treatment with isorhamnetin counteracted these neurodegenerative presentations. In the SH-SY5Y-derived neuronal cells, IL-6 upregulated the phosphorylation of tyrosine kinase 2 (TYK2) and signal transducer and activator of transcription 1 (STAT1), whereas isorhamnetin normalized this abnormal phosphorylation. Overexpression of TYK2 attenuated the neuroprotective effect of isorhamnetin on IL-6-induced neurotoxicity. Our findings demonstrate that isorhamnetin exerts its neuroprotective effect by mediating the neuroinflammatory IL-6/TYK2 signaling pathway, suggesting its potential for treating AD.

Lactulose and Melibiose Attenuate MPTP-Induced Parkinson's Disease in Mice by Inhibition of Oxidative Stress, Reduction of Neuroinflammation and Up-Regulation of Autophagy.

Parkinson's disease (PD) is a common neurodegenerative disease characterized by the progressive loss of dopaminergic (DAergic) neurons in the ventral brain. A disaccharide trehalose has demonstrated the potential to mitigate the DAergic loss in disease models for PD. However, trehalose is rapidly hydrolyzed into glucose by trehalase in the intestine, limiting its potential for clinical practice. Here, we investigated the neuroprotective potential of two trehalase-indigestible analogs, lactulose and melibiose, in sub-chronic 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mouse model of PD. Treatment with MPTP generated significant motor deficits, inhibited dopamine levels, and down-regulated dopamine transporter (DAT) in the striatum. Expression levels of genes involved in anti-oxidative stress pathways, including superoxide dismutase 2 (SOD2), nuclear factor erythroid 2-related factor 2 (NRF2), and NAD(P)H dehydrogenase (NQO1) were also down-regulated. Meanwhile, expression of the oxidative stress marker 4-hydroxynonenal (4-HNE) was up-regulated along with increased microglia and astrocyte reactivity in the ventral midbrain following MPTP treatment. MPTP also reduced the activity of autophagy, evaluated by the autophagosomal marker microtubule-associated protein 1 light chain 3 (LC3)-II. Lactulose and melibiose significantly rescued motor deficits, increased dopamine in the striatum, reduced microglia and astrocyte reactivity as well as decreased levels of 4-HNE. Furthermore, lactulose and melibiose up-regulated SOD2, NRF2, and NQO1 levels, as well as enhanced the LC3-II/LC3-I ratio in the ventral midbrain with MPTP treatment. Our findings indicate the potential of lactulose and melibiose to protect DAergic neurons in PD.

Neuroprotection of Indole-Derivative Compound NC001-8 by the Regulation of the NRF2 Pathway in Parkinson's Disease Cell Models.

Parkinson's disease (PD) is a common neurodegenerative disease accompanied by a loss of dopaminergic (DAergic) neurons. The development of therapies to prevent disease progression is the main goal of drug discovery. There is increasing evidence that oxidative stress and antioxidants may contribute to the pathogenesis and treatment of PD, respectively. In the present study, we investigated the antioxidative protective effects of the indole-derivative compound NC001-8 in DAergic neurons derived from SH-SY5Y cells and PD-specific induced pluripotent stem cells (PD-iPSCs) carrying a PARKIN ex5del mutation. In SH-SY5Y-differentiated DAergic neurons under 1-methyl-4-phenylpyridinium (MPP+) treatment, NC001-8 remarkably reduced the levels of reactive oxygen species (ROS) and cleaved caspase 3; upregulated nuclear factor erythroid 2-related factor 2 (NRF2) and NAD(P)H dehydrogenase, quinone 1 (NQO1); and promoted neuronal viability. In contrast, NRF2 knockdown abolished the effect of NC001-8 on the reduction of ROS and improvement of neuronal viability. In H2O2-treated DAergic neurons differentiated from PD-iPSCs, NC001-8 rescued the aberrant increase in ROS and cleaved caspase 3 by upregulating NRF2 and NQO1. Our results demonstrated the protective effect of NC001-8 in DAergic neurons via promoting the NRF2 antioxidative pathway and reducing ROS levels. We anticipate that our present in vitro assays may be a starting point for more sophisticated in vivo models or clinical trials that evaluate the potential of NC001-8 as a disease modifier for PD.

SOX9 as a Predictor for Neurogenesis Potentiality of Amniotic Fluid Stem Cells.

Preclinical studies of amniotic fluid-derived cell therapy have been successful in the research of neurodegenerative diseases, peripheral nerve injury, spinal cord injury, and brain ischemia. Transplantation of human amniotic fluid stem cells (AFSCs) into rat brain ventricles has shown improvement in symptoms of Parkinson's disease and also highlighted the minimal immune rejection risk of AFSCs, even between species. Although AFSCs appeared to be a promising resource for cell-based regenerative therapy, AFSCs contain a heterogeneous pool of distinct cell types, rendering each preparation of AFSCs unique. Identification of predictive markers for neuron-prone AFSCs is necessary before such stem cell-based therapeutics can become a reality. In an attempt to identify markers of AFSCs to predict their ability for neurogenesis, we performed a two-phase study. In the discovery phase of 23 AFSCs, we tested ZNF521/Zfp521, OCT6, SOX1, SOX2, SOX3, and SOX9 as predictive markers of AFSCs for neural differentiation. In the validation phase, the efficacy of these predictive markers was tested in independent sets of 18 AFSCs and 14 dental pulp stem cells (DPSCs). We found that high expression of SOX9 in AFSCs is associated with good neurogenetic ability, and these positive correlations were confirmed in independent sets of AFSCs and DPSCs. Furthermore, knockdown of SOX9 in AFSCs inhibited their neuronal differentiation. In conclusion, the discovery of SOX9 as a predictive marker for neuron-prone AFSCs could expedite the selection of useful clones for regenerative medicine, in particular, in neurological diseases and injuries.

Mitochondrial activation in the growth-restricted fetus of monochorionic twins.

OBJECTIVE: To study the regulatory mechanisms of selective intrauterine growth restriction (sIUGR) independent of confounding genetic factors, monochorionic (MC) twins are the ideal model, because they have identical genomic DNA. We hypothesize that the intrauterine growth restriction fetus has mitochondrial activation compared with its larger counterpart, and sought to demonstrate this using the MC twin model. DESIGN: Fetal cord blood and amniotic fluid of MC twins were prospectively collected during delivery. Mitochondrial DNA of cord blood was measured using real-time quantitative polymerase chain reaction (PCR), and mitochondria in amniotic fluid mesenchymal stem cells (AFMSCs) were analyzed with MitoTracker staining. SETTING: Tertiary referring center. PATIENT(S): Forty-three pairs of MC twins, including 24 pairs with sIUGR and 19 pairs without. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Mitochondrial DNA contents were measured and presented as fold difference between the small and large fetuses. After staining with MitoTracker, mitochondrial intensity in AFMSCs was analyzed with the Image J program. RESULT(S): The fold differences of the cord blood mitochondrial DNA content between the small and large twins were significantly higher in the MC twins with sIGUR (2.5 ± 1.2, n = 24 pairs) than in those without sIUGR (1.2 ± 0.3, n = 19 pairs). In addition, mitochondrial staining intensities were significantly higher in the AFMSCs derived from growth-restricted fetuses than from control fetuses. CONCLUSION(S): Mitochondrial activation in the sIUGR fetus of MC twins was likely regulated by locally adverse placental and blood flow conditions, instead of genetic factors.

MicroRNA and messenger RNA analyses of mesenchymal stem cells derived from teeth and the Wharton jelly of umbilical cord.

Microarray analyses of transcriptomes have been used to characterize mesenchymal stem cells (MSCs) of various origins. MicroRNAs (miRNAs) are short, nonprotein-coding RNAs involved in post-transcriptional gene inhibition in a variety of tissues, including cancer cells and MSCs. This study has integrated the use of miRNA and mRNA expression profiles to analyze human MSCs derived from Wharton's jelly (WJ) of the umbilical cord, milk teeth (MT), and adult wisdom teeth (AT). Because both miRNA and mRNA expression in MT and AT MSCs were so similar, they were combined together as tooth MSCs for comparison with WJ MSCs. Twenty-five genes that were up-regulated in tooth MSCs and 41 genes that were up-regulated in WJ MSCs were identified by cross-correlating miRNA and mRNA profiles. Functional network analysis show that tooth MSCs signature genes, represented by SATB2 and TNFRSF11B, are involved in ossification, bone development, and actin cytoskeleton organization. In addition, 2 upregulated genes of tooth MSCs-NEDD4 and EMP1-have been shown to be involved in neuroectodermal differentiation. The signature genes of WJ MSCs, represented by KAL1 and PAPPA, are involved in tissue development, regulation of cell differentiation, and bone morphogenetic protein signaling pathways. In conclusion, the combined interrogation of miRNA and mRNA expression profiles in this study proved useful in extracting reliable results from a genome-wide comparison of multiple types of MSCs. Subsequent functional network analysis provided further functional insights about these MSCs.

Macrophage inflammatory protein-3alpha is a novel serum marker for nasopharyngeal carcinoma detection and prediction of treatment outcomes.

PURPOSE: We herein examine whether macrophage inflammatory protein-3alpha (MIP-3alpha) is a biomarker for nasopharyngeal carcinoma (NPC) and whether it is involved in modulating NPC cell functions. EXPERIMENTAL DESIGN: The study population comprises 275 NPC patients and 250 controls. MIP-3alpha levels in tissues and sera were examined by immunohistochemistry and ELISA, respectively. EBV DNA load and EBV viral capsid antigen IgA were measured by quantitative real-time PCR and immunofluorescence assay, respectively. Effects of MIP-3alpha on NPC cell motility were investigated by Transwell migration/invasion assays and RNA interference. RESULTS: MIP-3alpha was overexpressed in NPC tumor cells. Serum MIP-3alpha levels were significantly higher in untreated patients, recurrent patients and patients with distant metastases versus non-NPC controls, patients with complete remission, and long-term disease-free patients. In the prospective cohort, serum MIP-3alpha levels were significantly higher in untreated NPC patients with advanced tumor-node-metastasis stage versus early stage and also correlated with EBV DNA load. Measurement of MIP-3alpha, EBV DNA, and viral capsid antigen IgA levels in serial serum/plasma samples from treated patients at 6-month intervals revealed a high association between MIP-3alpha level, EBV DNA load, and disease status. Among 155 consecutive NPC patients, subjects with pretreated MIP-3alpha serum levels over 65 pg/mL had worse prognoses for overall survival and distant metastasis-free survival in univariate and multivariate analysis. Additionally, cell functional assays showed that MIP-3alpha contributed to migration and invasion of NPC cells, which could be effectively inhibited by MIP-3alpha knockdown. CONCLUSIONS: MIP-3alpha may be a novel biomarker and prognosticator for NPC and is involved in migration and invasion of NPC cells.