- Synaptic dysfunction and altered excitability in C9ORF72 ALS/FTD. [Journal Article]
- BRBrain Res 2018 Feb 14
- Amyotrophic lateral sclerosis (ALS) is characterized by a progressive degeneration of upper and lower motor neurons, resulting in fatal paralysis due to denervation of the muscle. Due to genetic, pat...
Amyotrophic lateral sclerosis (ALS) is characterized by a progressive degeneration of upper and lower motor neurons, resulting in fatal paralysis due to denervation of the muscle. Due to genetic, pathological and symptomatic overlap, ALS is now considered a spectrum disease together with frontotemporal dementia (FTD), the second most common cause of dementia in individuals under the age of 65. Interestingly, in both diseases, there is a large prevalence of RNA binding proteins (RBPs) that are mutated and considered disease-causing, or whose dysfunction contribute to disease pathogenesis. The most common shared genetic mutation in ALS/FTD is a hexanucleuotide repeat expansion within intron 1 of C9ORF72 (C9). Three potentially overlapping putative toxic mechanisms causing disease pathogenesis have been proposed: loss of function due to haploinsufficient expression of the C9ORF72 mRNA, gain of function of the repeat RNA aggregates, or RNA foci, and repeat-associated non-ATG-initiated translation (RAN) of the repeat RNA into toxic dipeptide repeats (DPRs). Regardless of the causative mechanism, disease symptoms are ultimately caused by a failure of neurotransmission in three regions: the brain, the spinal cord, and the neuromuscular junction. Here, we review C9 ALS/FTD-associated synaptic dysfunction and aberrant neuronal excitability in these three key regions, focusing on changes in morphology and synapse formation, excitability, and excitotoxicity in patients, animal models, and in vitro models. We compare these deficits to those seen in other forms of ALS and FTD in search of shared pathways, and discuss the potential targeting of synaptic dysfunctions for therapeutic intervention in ALS and FTD patients.
- Transposable elements shape the human proteome landscape via formation of cis-acting upstream open reading frames. [Journal Article]
- GCGenes Cells 2018 Feb 15
- Transposons are major drivers of mammalian genome evolution. To obtain new insights into the contribution of transposons to the regulation of protein translation, we here examined how transposons aff...
Transposons are major drivers of mammalian genome evolution. To obtain new insights into the contribution of transposons to the regulation of protein translation, we here examined how transposons affected the genesis and function of upstream open reading frames (uORFs), which serve as cis-acting elements to regulate translation from annotated ORFs (anORFs) located downstream of the uORFs in eukaryotic mRNAs. Among 39,786 human uORFs, 3,992 had ATG trinucleotides of a transposon origin, termed "transposon-derived upstream ATGs" or TuATGs. Luciferase reporter assays suggested that many TuATGs modulate translation from anORFs. Comparisons with transposon consensus sequences revealed that most TuATGs were generated by nucleotide substitutions in non-ATG trinucleotides of integrated transposons. Among these non-ATG trinucleotides, GTG and ACG were converted into TuATGs more frequently, indicating a CpG methylation-mediated process of TuATG formation. Interestingly, it is likely that this process accelerated human-specific upstream ATG formation within transposon sequences in 5' untranslated regions after divergence between human and nonhuman primates. Methylation-mediated TuATG formation seems to be ongoing in the modern human population and could alter the expression of disease-related proteins. This study shows that transposons have potentially been shaping the human proteome landscape via cis-acting uORF creation.
- Investigating miRNA-661 and ATG4-B mRNA expression as potential biomarkers for hepatocellular carcinoma. [Journal Article]
- BMBiomark Med 2018 Feb 14
- CONCLUSIONS: Our data are the first report of its kind regarding the considerable clinical significance of miR-661 and ATG-4B mRNA in HCC patients.
- Targeted knock-in of CreERT2in zebrafish using CRISPR/Cas9. [Journal Article]
- CTCell Tissue Res 2018 Feb 12
- New genome-editing approaches, such as the CRISPR/Cas system, have opened up great opportunities to insert or delete genes at targeted loci and have revolutionized genetics in model organisms like th...
New genome-editing approaches, such as the CRISPR/Cas system, have opened up great opportunities to insert or delete genes at targeted loci and have revolutionized genetics in model organisms like the zebrafish. The Cre-loxp recombination system is widely used to activate or inactivate genes with high spatial and temporal specificity. Using a CRISPR/Cas9-mediated knock-in strategy, we inserted a zebrafish codon-optimized CreERT2transgene at the otx2 gene locus to generate a conditional Cre-driver line. We chose otx2 as it is a patterning gene of the anterior neural plate that is expressed during early development. By knocking in CreERT2upstream of the endogenous ATG of otx2, we utilized this gene's native promoter and enhancer elements to perfectly match CreERT2and endogenous otx2 expression patterns. Next, by combining this novel driver line with a Cre-dependent reporter line, we show that only in the presence of tamoxifen can efficient Cre-loxp-mediated recombination be achieved in the anterior neural plate-derived tissues like the telencephalon, the eye and the optic tectum. Our results imply that the otx2:CreERT2transgenic fish will be a valuable tool for lineage tracing and conditional mutant studies in larval and adult zebrafish.
- Efficacy and safety of combined immunosuppressive therapy plus umbilical cord blood infusion in severe aplastic anemia patients: A cohort study. [Journal Article]
- ETExp Ther Med 2018; 15(2):1966-1974
- The present study aimed to evaluate the efficacy and safety of combined immunosuppressive therapy (IST) plus umbilical cord blood infusion (UCBI) in severe aplastic anemia (SAA) patients. A total of ...
The present study aimed to evaluate the efficacy and safety of combined immunosuppressive therapy (IST) plus umbilical cord blood infusion (UCBI) in severe aplastic anemia (SAA) patients. A total of 68 patients with SAA were enrolled in the current prospective cohort study and divided into the IST (n=35; positive control) and IST+UCBI (n=33; experimental) groups according to the treatment conditions. Patients in the IST group were treated with rabbit antithymocyte globulin (r-ATG) at a dose of 2.5 mg/kg through intravenous infusion once a day for five days. This was combined with oral cyclosporine A (CsA) at a dose of 3-5 mg/kg twice a day for 2 years. Patients in the IST+UBCI group were treated with r-ATG and CsA at the same doses and frequencies as the IST group plus one UCBI 1 day after the final treatment with r-ATG. At 6 months post treatment, the complete response and overall response rate (ORR) of the IST+UCBI group were markedly higher compared with those in the IST group. Furthermore, patients in the IST+UCBI group achieved absolute neutrophil count (ANC) and platelet count responses more rapidly as compared with the IST group. However, no difference in the hemoglobin (Hb) response was identified between the two groups. In addition, SAA patients achieved responses in the ANC and platelet count more rapidly in comparison with very severe aplastic anemia (VSAA) patients, while the number of days to Hb responses were similar in the SAA and VSAA patients. Multivariate logistic regression analysis also revealed that IST+UCBI treatment was an independent predicting factor for patients achieving complete response or partial response, whereas VSAA was an independent predictor of a worse ORR. Platelet and reticulocyte were also independent predicting factors. Finally, the survival of patients was similar between the groups, and no difference in the safety of the treatment was observed. In conclusion, combined IST plus UCBI treatment may be applied as an effective and safe therapy for SAA patients.
- Allogeneic Matched Related Donor Bone Marrow Transplantation for Pediatric Patients With Severe Aplastic Anemia Using "Low-dose" Cyclophosphamide, ATG Plus Fludarabine. [Journal Article]
- JPJ Pediatr Hematol Oncol 2018 Feb 09
- CONCLUSIONS: This small pilot study shows that this cytoreductive regimen could be considered as the standard of care for transplantation of pediatric patients with aplastic anemia from HLA-matched siblings.
- Impaired thymopoiesis predicts for a high risk of severe infections after reduced intensity conditioning without anti-thymocyte globulin in double umbilical cord blood transplantation. [Journal Article]
- BMBone Marrow Transplant 2018 Feb 09
- Umbilical cord blood stem cell transplantation (UCBT) is associated with retarded hematopoietic recovery and immune reconstitution and a high infection-related morbidity and mortality, especially aft...
Umbilical cord blood stem cell transplantation (UCBT) is associated with retarded hematopoietic recovery and immune reconstitution and a high infection-related morbidity and mortality, especially after conditioning including anti-thymocyte globulin (ATG). However, data on immune recovery, incidence of infections, and outcome in double UCBT (dUCBT) recipients receiving an ATG-free reduced intensity conditioning (RIC) are lacking. In this study, recovery of lymphocyte subsets, thymopoiesis, and its association with severe infections and clinical outcome was assessed in a group of 55 recipients of a dUCBT ATG-free RIC regimen. T cell recovery was severely protracted in the majority of patients. However, T cell receptor excision circle TREC+T cells were detectable in 62% of patients at 3 months post-transplantation. A total of 128 common toxicity criteria grade 3-4 infections were observed in the first year post-transplantation. Non-relapse mortality at 12 months post-transplant was 16%, of which 78% infectious mortality. One-year overall survival was 73%. Patients who failed to recover thymopoiesis at 3 months post-transplantation were at a 3.3-fold higher risk of subsequent severe grade 3-4 infections.
- Impaired autophagic flux and its related inflammation in patients with adult-onset Still's disease. [Journal Article]
- OOncotarget 2018 Jan 02; 9(1):110-121
- The pathogenic role of autophagic immune regulation in adult-onset Still's disease (AOSD) is unclear. We investigated the relative levels of autophagy in AOSD patients and healthy controls, its assoc...
The pathogenic role of autophagic immune regulation in adult-onset Still's disease (AOSD) is unclear. We investigated the relative levels of autophagy in AOSD patients and healthy controls, its association with disease activity or course, and the change in autophagy after 6 months of therapy. Autophagosome levels were determined from the mean fluorescence intensity of autophagosomotropic dye incorporated into circulating immune cells. The fluorescent signal from lymphocytes, monocytes, and granulocytes from AOSD patients was greater than from controls. Levels of p62 fluorescence measured using flow cytometry in lymphocytes and granulocytes from AOSD patients was greater than in the corresponding cells from healthy controls. Expression of Atg5 and LC3-II mRNA and protein levels of p62 and LC3-II were elevated in AOSD patients. Moreover, AOSD activity scores correlated positively with autophagosome levels in monocytes and granulocytes, p62 levels in circulating immune cells, and levels of Beclin-1, Atg5, and LC3-II mRNA. Autophagosome levels and Atg mRNA expression decreased with disease remission in AOSD patients. Elevated autophagosome formation and p62 levels suggest impaired autophagic flux in AOSD.
- Danazol increases T regulatory cells in patients with aplastic anemia. [Journal Article]
- HHematology 2018 Feb 08; :1-5
- CONCLUSIONS: The rise in T-regs' percentage was higher in patients treated with Danazol alone when compared to standard IST (ATG with Cyclosporine), or Cyclosporine with Danazol combinations (p = 0.585).We conclude that Danazol also leads to increase in T-regs in acquired idiopathic AA.
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- Membrane Trafficking in Autophagy. [Journal Article]
- IRInt Rev Cell Mol Biol 2018; 336:1-92
- Macroautophagy is an intracellular pathway used for targeting of cellular components to the lysosome for their degradation and involves sequestration of cytoplasmic material into autophagosomes forme...
Macroautophagy is an intracellular pathway used for targeting of cellular components to the lysosome for their degradation and involves sequestration of cytoplasmic material into autophagosomes formed from a double membrane structure called the phagophore. The nucleation and elongation of the phagophore is tightly regulated by several autophagy-related (ATG) proteins, but also involves vesicular trafficking from different subcellular compartments to the forming autophagosome. Such trafficking must be tightly regulated by various intra- and extracellular signals to respond to different cellular stressors and metabolic states, as well as the nature of the cargo to become degraded. We are only starting to understand the interconnections between different membrane trafficking pathways and macroautophagy. This review will focus on the membrane trafficking machinery found to be involved in delivery of membrane, lipids, and proteins to the forming autophagosome and in the subsequent autophagosome fusion with endolysosomal membranes. The role of RAB proteins and their regulators, as well as coat proteins, vesicle tethers, and SNARE proteins in autophagosome biogenesis and maturation will be discussed.