miR-139-5p upregulation alleviated spontaneous recurrent epileptiform discharge-induced oxidative stress and apoptosis in rat hippocampal neurons via regulating the Notch pathway

SNHG3 deficiency restrains spinal cord injury-induced inflammation through sponging miR-139-5p and provides a novel biomarker for disease severity

BACKGROUND

MicroRNAs and long non-coding RNAs play pivotal roles in the progression and recovery of spinal cord injury (SCI), which is a serious traumatic disease in central nervous system. The purpose of this study was to investigate the expression and clinical value of SNHG3 in SCI patients and explore the regulatory effects of SNHG3 on SCI-induced inflammatory responses in vitro.

METHODS

The relationship between SNHG3 and miR-139-5p was confirmed using a dual-luciferase reporter assay. A SCI cell model was constructed in SH-SY5Y cells using hypoxia treatment. SNHG3 and miR-139-5p expression was analyzed using qRT-PCR. Effects of SNHG3 and miR-139-5p on cell model viability and inflammatory cytokines were evaluated by CCK-8 assay and ELISA kits, respectively. ROC curves based on serum SNHG3 and miR-139-5p were constructed to evaluate their diagnostic performance.

RESULTS

In SCI patients, serum SNHG3 was upregulated, but miR-139-5p was downregulated (P<0.05), and a negative correlation between the two ncRNAs was found. Both SNHG3 and miR-139-5p showed relatively high discrimination abilities for the screening of SCI and complete SCI (CSCI) patients. SNHG3 was positively correlated with inflammatory cytokines, and miR-139-5p showed opposite results in SCI patients. By in-vitro analysis, SNHG3 knockdown enhanced cell viability but inhibited inflammation by increasing miR-139-5p.

CONCLUSIONS

All the data found that serum upregulated SNHG3 and downregulated miR-139-5p served as biomarkers to diagnose SCI and indicate injury severity. The deficiency of SNHG3 alleviated neuronal injury by restraining inflammatory responses through targeting miR-139-5p. Thus, the SNHG3/miR-139-5p axis may provide novel biomarkers and therapeutic targets for SCI.

Epigenetic regulation in epilepsy: A novel mechanism and therapeutic strategy for epilepsy

Epilepsy is a common neurological disorder characterized by recurrent seizures with excessive and abnormal neuronal discharges. Epileptogenesis is usually involved in neuropathological processes such as ion channel dysfunction, neuronal injury, inflammatory response, synaptic plasticity, gliocyte proliferation and mossy fiber sprouting, currently the pathogenesis of epilepsy is not yet completely understood. A growing body of studies have shown that epigenetic regulation, such as histone modifications, DNA methylation, noncoding RNAs (ncRNAs), N6-methyladenosine (m6A) and restrictive element-1 silencing transcription factor/neuron-restrictive silencing factor (REST/NRSF) are also involved in epilepsy. Through epigenetic studies, we found that the synaptic dysfunction, nerve damage, cognitive dysfunction and brain development abnormalities are affected by epigenetic regulation of epilepsy-related genes in patients with epilepsy. However, the functional roles of epigenetics in pathogenesis and treatment of epilepsy are still to be explored. Therefore, profiling the array of genes that are epigenetically dysregulated in epileptogenesis is likely to advance our understanding of the mechanisms underlying the pathophysiology of epilepsy and may for the amelioration of these serious human conditions provide novel insight into therapeutic strategies and diagnostic biomarkers for epilepsy to improve serious human condition.

Disorders of the central nervous system: Insights from Notch and Nrf2 signaling

The functional complexity of the central nervous system (CNS) is unparalleled in living organisms. It arises from neural crest-derived cells that migrate by the exact route, leading to the formation of a complex network of neurons and glial cells. Recent studies have shown that novel crosstalk exists between the Notch1 and Nrf2 pathways and is associated with many neurological diseases. The Notch1-Nrf2 axis may act on nervous system development, and the molecular mechanism has recently been reported. In this review, we summarize the essential structure and function of the CNS. The significance of interactions between signaling pathways and between developmental processes like proliferation, apoptosis and migration in ensuring the correct development of the CNS is also presented. We primarily focus on research concerning possible mechanism of interaction between Notch1 and Nrf2 and the functions of Notch1-Nrf2 in neurons. There may be a direct interaction between Notch1 and NRF2, which is closely related to the crosstalk that occurs between them. The significance and potential applications of the Notch1-Nrf2 axis in abnormal development of the nervous system are been highlighten. We also discuss the molecular mechanisms by which the Notch1-Nrf2 axis controls the apoptosis, antioxidant pathway and differentiation of neurons to modulate the development of the nervous system. This information will lead to a better understanding of Notch1-Nrf2 axis signaling pathways in the nervous system and may facilitate the development of new therapeutic strategies.

MicroRNA-139-5p suppresses non-small cell lung cancer progression by targeting ATAD2

MiR-139-5p is a suppressor in multiple types of cancer. However, whether miR-139-5p affects NSCLC is unknown. In this study, miR-139-5p expression in clinical samples was examined by real-time PCR and in situ hybridization (ISH). MiR-139-5p mimic was transfected to monitor NSCLC cell behaviors. Potential target was predicated using bioinformatics database. Next, whether miR-139-5p impacted cell behaviors via regulation of its predicted target gene were further evaluated. The result revealed that miR-139-5p was lower in NSCLC samples/cells. MiR-139-5p restrained A549 cell proliferation, accelerated apoptosis, and inhibited the β-catenin signaling. ATAD2 was a predicted target of miR-139-5p, and it was highly expressed in NSCLC tissues. ATAD2 overexpression abolished the miR-139-5p's anti-tumor effect on cell proliferation and apoptosis. TWS119 (a β-catenin signaling activator) partially reversed miR-139-5p overexpression-induced suppression of cell proliferation and promotion of cell apoptosis. In tumor xenografts, miR-139-5p restrained tumor growth. MiR-139-5p was a tumor suppressor in NSCLC by regulating the oncogene ATAD2 and β-catenin signaling. Our study provides a promising target for cancer treatment.

Xenon inhalation attenuates neuronal injury and prevents epilepsy in febrile seizure Sprague-Dawley pups

Background

Febrile seizures (FS) usually occur in childhood and may cause irreversible neuronal damage, cognitive functional defects, and an increase in the risk of epilepsy later in life. Anti-epileptic drugs (AEDs), currently used to treat FS in children, can relieve seizures. However, their effects in preventing the risk of developing epilepsy in later life are unsatisfactory. Moreover, AEDs may damage child brain development. Here, we evaluated the efficiency of xenon in treating prolonged FS (PFS) and preventing epilepsy in Sprague-Dawley pups.

Methods

Prolonged FS was induced by hyperthermic treatment. After 90 min of PFS, the pups in the xenon treatment group were immediately treated with 70% xenon/21% oxygen/9% nitrogen for 60 min. The levels of glutamate, mitochondrial oxidative stress, mitophagy, and neuronal injury, seizures, learning, and memory functions were measured at specific time points.

Results

Neonatal period PFS led to spontaneous seizure, learning and memory dysfunction, accompanied by increased levels of glutamate, mitochondrial oxidative stress, mitophagy, and neuronal injury. Xenon treatment alleviated the changes caused by PFS and reduced the risk of PFS developing into epilepsy later.

Conclusion

Our results suggest that xenon inhalation could be a potential therapeutic strategy to attenuate neuronal injury and prevent epilepsy in patients with FS.

Attenuated iron stress and oxidative stress may participate in anti-seizure and neuroprotective roles of xenon in pentylenetetrazole-induced epileptogenesis

The previous studies have demonstrated the excellent neuroprotective effects of xenon. In this study, we verified the anti-seizure and neuroprotective roles of xenon in epileptogenesis and evaluated the involvement of oxidative stress and iron accumulation in the protective roles of xenon. Epileptogenesis was induced by pentylenetetrazole (PTZ) treatment in Sprague-Dawley rats. During epileptogenesis, we found increased levels of iron and oxidative stress accompanied by elevated levels of divalent metal transporter protein 1 and iron regulatory protein 1, which are closely associated with iron accumulation. Meanwhile, the levels of autophagy and mitophagy increased, alongside significant neuronal damage and cognitive deficits. Xenon treatment reversed these effects: oxidative stress and iron stress were reduced, neuronal injury and seizure severity were attenuated, and learning and memory deficits were improved. Thus, our results confirmed the neuroprotective and anti-seizure effects of xenon treatment in PTZ-induced epileptogenesis. The reduction in oxidative and iron stress may be the main mechanisms underlying xenon treatment. Thus, this study provides a potential intervention strategy for epileptogenesis.

Neuronal nitric oxide synthase/reactive oxygen species pathway is involved in apoptosis and pyroptosis in epilepsy

Dysfunction of neuronal nitric oxide synthase contributes to neurotoxicity, which triggers cell death in various neuropathological diseases, including epilepsy. Studies have shown that inhibition of neuronal nitric oxide synthase activity increases the epilepsy threshold, that is, has an anticonvulsant effect. However, the exact role and potential mechanism of neuronal nitric oxide synthase in seizures are still unclear. In this study, we performed RNA sequencing, functional enrichment analysis, and weighted gene coexpression network analysis of the hippocampus of tremor rats, a rat model of genetic epilepsy. We found damaged hippocampal mitochondria and abnormal succinate dehydrogenase level and Na⁺-K⁺-ATPase activity. In addition, we used a pilocarpine-induced N2a cell model to mimic epileptic injury. After application of neuronal nitric oxide synthase inhibitor 7-nitroindazole, changes in malondialdehyde, lactate dehydrogenase and superoxide dismutase, which are associated with oxidative stress, were reversed, and the increase in reactive oxygen species level was reversed by 7-nitroindazole or reactive oxygen species inhibitor N-acetylcysteine. Application of 7-nitroindazole or N-acetylcysteine downregulated the expression of caspase-3 and cytochrome c and reversed the apoptosis of epileptic cells. Furthermore, 7-nitroindazole or N-acetylcysteine downregulated the abnormally high expression of NLRP3, gasdermin-D, interleukin-1β and interleukin-18. This indicated that 7-nitroindazole and N-acetylcysteine each reversed epileptic cell death. Taken together, our findings suggest that the neuronal nitric oxide synthase/reactive oxygen species pathway is involved in pyroptosis of epileptic cells, and inhibiting neuronal nitric oxide synthase activity or its induced oxidative stress may play a neuroprotective role in epilepsy.

Circ_0077109 sponges miR-139-5p and upregulates HOXD10 in trophoblast cells as potential mechanism for preeclampsia progression

BACKGROUND

One of the important reasons for the development of preeclampsia (PE) is the abnormal function of trophoblast cells. Many circular RNAs (circRNAs) have been confirmed to participate in the regulation of trophoblast cell function to mediate PE progression. However, whether circ_0077109 is involved in PE progression through regulating trophoblast cell function remains unclear.

METHODS

Quantitative real-time PCR was utilized for measuring the expression of circ_0077109, microRNA (miR)-139-5p and homeobox D10 (HOXD10). Trophoblast cell proliferation, apoptosis, invasion, and angiogenesis was assessed cell counting kit 8 assay, EdU assay, flow cytometry, transwell assay and tube formation assay. In addition, western blot analysis was used to determine protein expression. The interaction between miR-139-5p and circ_0077109 or HOXD10 was verified by dual-luciferase reporter assay and RIP assay.

RESULTS

Our results pointed out that circ_0077109 was a circRNA with upregulated expression in PE patients. Overexpression of circ_0077109 suppressed trophoblast cell proliferation, invasion, and angiogenesis, while increased apoptosis. MiR-139-5p was found to be sponged by circ_0077109, and its mimic reversed the suppressive effect of circ_0077109 on trophoblast cell function. HOXD10 was a target of miR-139-5p, and its overexpression inhibited trophoblast cell proliferation, invasion, and angiogenesis. MiR-139-5p inhibitor could repress trophoblast cell function, while this effect could be reversed by HOXD10 knockdown.

CONCLUSION

In summary, we confirmed that circ_0077109 inhibited trophoblast cell function through the regulation of miR-139-5p/HOXD10 axis, which might be a potential target for PE treatment. This article is protected by copyright. All rights reserved.

Aberrant expression of miRNAs in epilepsy

Epilepsy is manifested by intermittent convulsions and alterations in consciousness. This disorder has serious effects on daily functions and physical and mental health of affected patients. A variety of temporary irregularities in the function of brain can results in epilepsy. The molecular mechanism of epilepsy and the underlying causes of abnormal apoptotic responses in neurons, dysregulation of regenerative mechanisms in glial cells and abnormal immune reactions in the context of epilepsy are not clear. microRNAs (miRNAs) as important regulators of cell apoptosis as well as regenerative and immune responses have been shown to affect pathologic events in epilepsy. In the current review, we aimed at defining the role of miRNAs in the pathophysiology of epilepsy. We have listed dysregulated miRNAs in animal models of epilepsy and human subjects. miR-25-3p, miR-494, miR-139-5p, miR-101a-3p, miR-344a, miR-129, miR-298 and miR-187 are among down-regulated miRNAs in epilepsy. Moreover, expressions of miR-132, miR-146a, miR-181a and miR-155 have been reported to be increased in epilepsy. A number of genetic variants within miRNAs can affect risk of epilepsy. We discuss the role of miRNAs in the development of epilepsy.