Yan Chang

Objectives: Microglia mediated neuronal inflammation has been reported to be responsible for neurodegenerative disease. Isoquercitrin (IQC), widely found in fruits, vegetables and foods, has high bioavailability and offers many benefits of humans. Although IQC has been shown to possess pleiotropic biological activities, but its anti-inflammatory mechanism in microglia at molecular level remains largely unclear. Therefore, this study aimed to investigate IQC’s inhibition on inflammation within BV2 microglia cells induced by lipopolysaccharide (LPS) and the underlying mechanism. Methods: The cell viability was tested by using the MTT assay and the NO production was measured by Griess reagent. Inflammatory cytokines expression was determined by RT-qPCR and the expression of iNOS、COX2 and correlation factor of NF-κB and MAPK pathway were determined by RT-qPCR and western blotting. Results: IQC does not affect the viability of LPS-stimulated microglia. IQC treatment inhibited LPS-triggered NO and PGE2 production, iNOS and COX2 expression and affected the mRNA levels of relative inflammatory cytokines. Moreover, IQC inhibited nuclear factor kappa B(NF-κB) and MAPK pathway activation mediated by LPS, thereby inhibiting the levels of inflammatory cytokines. Conclusions: IQC exhibited remarkable anti-inflammatory effects and promised therapeutic potential for neural inflammation associated diseases.

Antisense nucleic acids are single-stranded oligonucleotides that have been specially chemically modified, which can bind to RNA expressed by target genes through base complementary pairing and affect protein synthesis at the level of posttranscriptional processing or protein translation. In recent years, the application of antisense nucleic acid technology in the treatment of neuromuscular diseases has made remarkable progress. In 2016, the US FDA approved two antisense nucleic acid drugs for the treatment of Duchenne muscular dystrophy (DMD) and spinal muscular atrophy (SMA), and the development to treat other neurodegenerative diseases has also entered the clinical stage. Therefore, ASO represents a treatment with great potential. The article will summarize ASO therapies in terms of mechanism of action, chemical modification, and administration methods and analyze their role in several common neurodegenerative diseases, such as SMA, DMD, and amyotrophic lateral sclerosis (ALS). This article systematically summarizes the great potential of antisense nucleic acid technology in the treatment of hereditary neurodegenerative diseases.

Heterogeneous nuclear ribonucleoprotein (HNRNP) A1 and A2 are the most abundant HNRNPs with nearly identical functions, and play important roles in regulating gene expression at multiple levels (i.e. transcription, posttranscription, and translation). However, the expression and regulation mechanism of HNRNPA1 and A2 themselves remain unclear. In this study, the amino acid sequences of HNRNPA1 and HNRNPA2 were compared and found to have 78% and 86% homology in key functional domains. Transfection of HEK293 cells with small interfering RNA and overexpression vectors of HNRNPA1 and HNRNPA2 demonstrated that HNRNPA1 and HNRNPA2 paralogs regulate each other's expression in a compensatory manner at both the RNA and protein levels. Multiprimer reverse transcription-polymerase chain reaction showed that HNRNPA1 and HNRNPA2 did not affect splicing of the HNRNPA2 and HNRNPA1 gene. Using luciferase reporting system, we found that compensatory degradation was mediated by the 3'UTR of the two genes rather than by the promoter. Moreover, treatment with cycloheximide inhibited the compensatory regulation. Our results indicate a novel regulation mechanism of HNRNPA1 and A2 expression. Through compensatory regulation, the expression levels of HNRNPA1 and HNRNPA2 are strictly controlled within a certain range to maintain normal cellular activities under different physiological conditions.