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Biology subjects

Eliyahu, T.

Publications and source records attributed to Eliyahu, T..

2 recordsLinked to original sources

Ladostigil attenuates the oxidative and ER stress in human neuroblast-like SH-SY5Y cells

A hallmark of the aging brain is the robust inflammation mediated by microglial activation. Neuroinflammation resulting from the induction of oxidative stress in neurodegenerative diseases and following brain injury. Chronic treatment of aging rats by ladostigil, a compound with antioxidant and anti-inflammatory function, prevented microglial activation and learning deficits. In this study, we investigate the effect of ladostigil on neuronal-like SH-SY5Y cells. We show that SH-SY5Y cells exposed to acute (by H2O2) or chronic oxidative stress (by Sin1, 3-morpholinosydnonimine) induced apoptotic cell death. However, in the presence of ladostigil, the decline in cell viability and the oxidative levels were partially reversed. RNA-seq analysis showed that chronic oxidation by Sin1 resulted in coordinated suppression of endoplasmic reticulum (ER) quality control and ER stress response gene sets. Chronic oxidative stress impacted ER proteostasis and induced the expression of numerous lncRNAs. Pre-incubation with ladostigil before exposing SH-SY5Y cells to Sin1 induced Clk1 (Cdc2-like kinase 1) which was implicated in psychophysiological stress in mice and Alzheimer disease. Ladostigil also suppressed the expression of Ccpg1 (Cell cycle progression 1) and Synj1 (Synaptojanin 1) that function in ER-autophagy and endocytic pathways. We postulate that ladostigil alleviated cell damage by oxidation and ER stress. Therefore, it may attenuate neurotoxicity and cell death that accompany chronic stress conditions in the aging brain.

cell biology

Spliceosome-Associated MicroRNAs Identified in Breast Cancer Cells Act on Nuclear Targets and Are Potential Indicators for Tumorigenicity

MicroRNAs (miRNAs) act as negative regulators of gene expression in the cytoplasm. Previous studies identified miRNAs associated with the spliceosome. Here we study three breast-derived cell-lines with increased tumorigenicity (from MCF-10A to MCF-7 and MDA-MB-231) and compared their miRNA sequences at the spliceosome fraction (SF). We report that the SF-miRNAs expression, identity, and pre-miRNA segmental composition vary across these cell-lines. The expression of the majority of the abundant SF-miRNAs (e.g. miR-100, miR-30a, and let-7 members) shows an opposite trend in view of the literature and breast cancer large cohorts. The results suggest that SF-miRNAs act in the nucleus on alternative targets than in the cytoplasm. One such miRNA is miR-7704 whose genomic position overlaps HAGLR, a cancer-related lncRNA. We found an inverse expression of miR-7704 and HAGLR in the tested cell lines. Moreover, inhibition of miR-7704 caused an increase in HAGLR expression. Furthermore, increasing miR-7704 levels attenuated the MDA-MB-231 cell-division rate. While miR-7704 acts as oncomiR in breast cancer patients, it has a tumor-suppressing function in SF, with HAGLR being its nuclear target. Manipulating miR-7704 levels is a potential lead for altering tumorigenicity. Altogether, we report on the potential of manipulating SF-miRNAs as an unexplored route for breast cancer therapeutics.

cancer biology