Analysis of the Clinical Diagnostic Value of GMFB in Cerebral Infarction

G9a Inhibition Promotes Neuroprotection through GMFB Regulation in Alzheimer's Disease

Epigenetic alterations are a fundamental pathological hallmark of Alzheimer's disease (AD). Herein, we show the upregulation of G9a and H3K9me2 in the brains of AD patients. Interestingly, treatment with a G9a inhibitor (G9ai) in SAMP8 mice reversed the high levels of H3K9me2 and rescued cognitive decline. A transcriptional profile analysis after G9ai treatment revealed increased gene expression of glia maturation factor β (GMFB) in SAMP8 mice. Besides, a H3K9me2 ChIP-seq analysis after G9a inhibition treatment showed the enrichment of gene promoters associated with neural functions. We observed the induction of neuronal plasticity and a reduction of neuroinflammation after G9ai treatment, and more strikingly, these neuroprotective effects were reverted by the pharmacological inhibition of GMFB in mice and cell cultures; this was also validated by the RNAi approach generating the knockdown of GMFB/Y507A.10 in Caenorhabditis elegans. Importantly, we present evidence that GMFB activity is controlled by G9a-mediated lysine methylation as well as we identified that G9a directly bound GMFB and catalyzed the methylation at lysine (K) 20 and K25 in vitro. Furthermore, we found that the neurodegenerative role of G9a as a GMFB suppressor would mainly rely on methylation of the K25 position of GMFB, and thus G9a pharmacological inhibition removes this methylation promoting neuroprotective effects. Then, our findings confirm an undescribed mechanism by which G9a inhibition acts at two levels, increasing GMFB and regulating its function to promote neuroprotective effects in age-related cognitive decline.

Fluid biomarkers in stroke: From animal models to clinical care

Stroke is a leading cause of death and disability worldwide. Stroke prevention, early diagnosis, and efficient acute treatment are priorities to successfully impact stroke death and disability. Fluid biomarkers may improve stroke differential diagnostic, patient stratification for acute treatment, and post-stroke individualized rehabilitation. In the present work, we characterized the use of stroke animal models in fluid biomarker research through a systematic review of PubMed and Scopus databases, followed by a literature review on the translation to the human stroke care setting and future perspectives in the field. We found increasing numbers of publications but with limited translation to the clinic. Animal studies are very heterogeneous, do not account for several human features present in stroke, and, importantly, only a minority of such studies used human cohorts to validate biomarker findings. Clinical studies have found appealing candidates, both protein and circulating nucleic acids, to contribute to a more personalized stroke care pathway. Still, brain tissue complexity and the fact that different brain pathologies share lesion biomarkers make this task challenging due to biomarker low specificity. Moreover, the study design and lack of validation cohorts may have precluded a formal integration of biomarkers in different steps of stroke diagnosis and treatment. To overcome such issues, recent pivotal studies on biomarker dynamics in individual patients are providing added value to diagnosis and anticipating patients' early prognosis. Presently, the most consistent protein biomarkers for stroke diagnosis and short- and long-term prognosis are associated with tissue damage at neuronal (TAU), axonal (NFL), or astroglial (GFAP and S100β) levels. Most promising nucleic acids are microRNAs (miR), due to their stability in plasma and ease of access. Still, clinical validation and standardized quantitation place them a step behind compared protein as stroke biomarkers. Ultimately, the definition of clinically relevant biomarker panels and optimization of fast and sensitive biomarker measurements in the blood, together with their combination with clinical and neuroimaging data, will pave the way toward personalized stroke care.

Transcriptional Activity of Neurotrophins Genes and Their Receptors in the Peripheral Blood in Patients with Thyroid Diseases in Bukovinian Population of Ukraine

Objective. Thyroid hormone has an especially strong impact on central nervous system development, and thyroid hormone deficiency has been shown to result in severe mental retardation. It is crucial to identify compensatory mechanisms that can be involved in improving cognitive function and the quality of life of patients with hypothyroidism. Methods: We used the pathway-specific PCR array (Neurotrophins and Receptors RT2 Profiler PCR Array, QIAGEN, Germany) to identify and validate neurotrophins genes and their receptor expression in patients with thyroid pathology and control group. Results: The analysis of gene expression of neurotrophins and their receptors showed that CRHBP, FRS2, FRS3, GFRA1, GFRA2, GMFB, NGF, NRG2, NRG4, NTF4, TRO, and VGF significantly decreased their expression in Group 3, which includes the patients with postoperative hypothyroidism. The patients with primary hypothyroidism stemming from AIT had significantly reduced expression of CRHBP, GFRA1, GFRA2, GMFB, NGF, PTGER2, and VGF, while the expression of NRG4 and TRO increased. In Group 3, which includes the patients with AIT and elevated serum anti-Tg and anti-TPO autoantibodies, the mRNA levels of GFRA2, NGF, NRG2, NTF4, NGF, PTGER were reduced, and the expression of CRHBP, FRS2, FRS3 GFRA1, GMFB, NRG4, TRO, and VGF significantly increased. Conclusion: These results indicate significant variability in the transcriptional activity of the genes of encoding neurotrophins and their receptors in the peripheral blood in people with thyroid diseases.