Residing on chromosome 20q13.13, Zinc Finger NFX1-Type Containing 1 (ZNFX1) antisense RNA 1 (ZFAS1) is a transcript which has been primarily recognized as a modulator of differentiation of alveolar and epithelial cell in the mammary gland. This long non-coding RNA (lncRNA) partakes in the molecular cascades leading to several non-neoplastic conditions such as osteoarthritis, epilepsy, rheumatoid arthritis, atherosclerosis, pulmonary fibrosis, myocardial infarction, and cardiac dysfunction. More importantly, ZFAS1 is considered as an oncogene in almost all types of cancers. Using expression amounts of ZFAS1, it is possible to forecast the clinical outcome of patients with different neoplasms such as colorectal cancer, gastric cancer, cholangiocarcinoma, hepatoblastoma, and other types of cancer. We describe the role of ZFAS1 in the development of neoplastic and non-neoplastic disorders.

Long non-coding RNAs (lncRNAs) have been confirmed to be involved in epilepsy development. It has been reported that lncRNA ZFAS1 plays a vital regulatory role in epilepsy progression. Therefore, the role and molecular mechanism of ZFAS1 in epilepsy progression deserve further investigation. Mice status epilepticus (SE) model was constructed, and hippocampal neurons were isolated from mice hippocampus tissues. The expression of ZFAS1, miR-15a-5p and oxidative stress responsive 1 (OXSR1) were determined by quantitative real-time PCR. ELISA assay was used to detect the concentrations of inflammation factors. Cell viability and apoptosis were examined by MTT assay, EdU staining and flow cytometry. Western blot analysis was conducted to measure protein levels, and the productions of SOD and MDA were measured to assess cell oxidative stress. Dual-luciferase reporter assay and RIP assay were employed to validate the relationship between miR-15a-5p and ZFAS1 or OXSR1. LncRNA ZFAS1 was highly expressed in SE mice and SE-stimulated hippocampal neurons. Silenced ZFAS1 promoted viability, while inhibited inflammation, apoptosis and oxidative stress in SE-induced hippocampal neurons. MiR-15a-5p could be targeted by ZFAS1, and its inhibitor also reversed the suppressive effect of ZFAS1 knockdown on SE-induced hippocampal neurons injury. In addition, OXSR1 was a target of miR-15a-5p, and its silencing also could relieve SE-induced hippocampal neurons injury. OXSR1 overexpression reversed the inhibition effect of miR-15a-5p on SE-induced hippocampal neurons injury. Moreover, ZFAS1 positively regulated OXSR1 expression by sponging miR-15a-5p, thereby activating the NF-κB pathway. LncRNA ZFAS1 might contribute to the progression of epilepsy by regulating the miR-15a-5p/OXSR1/NF-κB pathway.

PURPOSE:This study aimed to elucidate whether lncRNA ZFAS1 is involved in neuronal apoptosis and inflammation in temporal lobe epilepsy (TLE). MATERIALS AND METHODS:Ninety-six TLE patients were recruited, and their peripheral venous blood was gathered to determine Zfas1 expression with polymerase chain reaction. Neurons were separated from hippocampal tissue of newborn SD rats, and si-Zfas1 or pcDNA3.1-Zfas1 was transfected into the neurons. Inflammatory cytokines released by neurons were determined, and neuronal activities were evaluated through MTT assay, colony formation assay, and flow cytometry. RESULTS:Serum levels of Zfas1 were higher in TLE patients than in healthy controls (<0.05). Furthermore, Zfas1 expression in neurons was raised by pcDNA3.1-Zfas1 and declined after silencing of Zfas1 (<0.05). Transfection of pcDNA-Zfas1 weakened the viability and proliferation of neurons and increased neuronal apoptosis (<0.05). Meanwhile, pcDNA3.1-Zfas1 transfection promoted lipopolysaccharide-induced release of cytokines, including tumor necrosis factor-α, interleukin (IL)-1, IL-6, and intercellular adhesion molecule-1 (<0.05), and boosted NF-κB activation by elevating the expression of NF-κB p65, pIκBα, and IKKβ in neurons (<0.05). CONCLUSION:Our results indicated that lncRNA ZFAS1 exacerbates epilepsy development by promoting neuronal apoptosis and inflammation, implying ZFAS1 as a promising treatment target for epilepsy.

Epilepsy is a common neurological disease. The dysregulated long noncoding RNAs (lncRNAs) are implicated in epileptogenesis. The aim of this research is to explore the role and mechanism of lncRNA zinc finger antisense 1 (ZFAS1) in status epilepticus (SE)-induced hippocampal neurons injury. SE mice model was established and primary hippocampal neurons were isolated. The expression levels of ZFAS1 and microRNA-421 (miR-421) were detected in hippocampus and hippocampal neurons via quantitative reverse transcription polymerase chain reaction. Hippocampal neurons viability, apoptosis and autophagy were analyzed via Cell Counting Kit-8, flow cytometry and western blot. The target relationship between ZFAS1 and miR-421 was analyzed via dual-luciferase reporter assay. The phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) pathway was blocked by LY294002 and related protein levels were detected via western blot. ZFAS1 expression was elevated in hippocampus and hippocampal neurons from SE mice. Knockdown of ZFAS1 increased SE hippocampal neurons viability and decreased apoptosis and autophagy. ZFAS1 could sponge miR-421. MiR-421 expression was declined in SE mice tissues and cells. Down-regulation of miR-421 abolished the suppressive effect of ZFAS1 knockdown on hippocampal neurons apoptosis and autophagy. Silencing of ZFAS1 induced activation of the PI3K/AKT pathway by up-regulating miR-421. Inhibition of the PI3K/AKT pathway reversed the effect of ZFAS1 knockdown on SE hippocampal neurons apoptosis and autophagy. Interference of ZFAS1 attenuated hippocampal neurons apoptosis and autophagy in SE by increasing miR-421 and activating the PI3K/AKT pathway, indicating a new mechanism for understanding the pathogenesis of SE.