Non-Coding RNA Regulatory Network in Ischemic Stroke

Advancing Ischemic Stroke Prognosis: Key Role of MiR-155 Non-Coding RNA

Ischemic stroke (IS) is the leading cause of long-term disability and the second leading cause of death worldwide. It remains a significant clinical problem because only supportive therapies exist, such as thrombolytic agents and surgical thrombectomy, which do not restore function. Understanding the molecular pathogenesis of IS, including dysfunction in oxidative homeostasis, apoptosis, neuroinflammation and neuroprotection, is crucial to developing therapies. Non-coding RNAs (ncRNAs) are master regulators, and one ncRNA that stands out is miR-155, a pro-inflammatory micro-RNA elevated in stroke. This review addresses the biological mechanisms reported in the literature that support using miR-155 as a biomarker and therapeutic agent to treat IS in patients.

Whole transcriptome analysis in oviduct provides insight into microRNAs and ceRNA regulative networks that targeted reproduction of goat (Capra hircus)

BACKGROUND

Reproduction traits are crucial for livestock breeding and represent key economic indicators in the domestic goat (Capra hircus) industry. The oviduct, a critical organ in female mammals, plays a pivotal role in several reproductive processes; however, its molecular mechanisms remain largely unknown. Non-coding RNA and mRNAs are essential regulatory elements in reproductive processes; yet their specific roles and regulatory networks in goat oviducts remain unclear.

RESULTS

In this study, we conducted small RNA sequencing of the oviduct in high- and low-fecundity goats during the follicular (FH and FL groups, n = 10) and luteal (LH and LL groups, n = 10) phase, profiling 20 tissue samples. Combinatorial whole-transcriptome expression profiles were applied to the same samples to uncover the competitive endogenous RNA (ceRNA) regulation network associated with goat fecundity. RT-qPCR was employed to validate the miRNA profiling results, and ceRNA regulatory networks were analyzed through luciferase assay. Gene set enrichment analysis (GSEA) confirmed that the cytokine-cytokine receptor interaction and TGF-β signaling pathway, both related to embryonic development, were enriched in DEM target genes. Additionally, miR-328-3p, a core miRNA, targets SMAD3 and BOP1, which are involved in the negative regulation of cell growth and embryonic development. TOB1 and TOB2, targeted by miR-204-3p, regulate cell proliferation via the protein kinase C-activating G-protein coupled receptor signaling pathway. Analyses of ceRNA regulatory networks revealed that LNC_005981 - miR-328-3p - SMAD3 and circ_0021923 - miR-204-3p - DOT1L may affect goats' reproduction, findings that were validated using luciferase assay.

CONCLUSION

Analysis of whole-transcriptome profiling of goat oviducts identified several key miRNAs and ceRNAs that may regulate oocyte maturation, embryo development, and the interactions between the oviduct and gametes/early embryos, providing insights into the molecular mechanisms of reproductive regulatory networks.

circLOC375190 promotes autophagy through modulation of the mTORC1/TFEB axis in acute ischemic stroke-induced neurological injury

OBJECTIVE

The authors explored differentially expressed circRNAs in Acute Ischemic Stroke (AIS) and revealed the role and potential downstream molecular mechanisms of circLOC375190.

METHODS

circLOC375190 expression was modulated by lentiviral injection in the brain of transient Middle Cerebral Artery Occlusion (tMCAO) mice. Neurological dysfunction was assessed, as well as infarction size, histopathological changes, and neuronal apoptosis in tMCAO mice. An in vitro Oxygen-Glucose Deprivation/Reoxygenation (OGD/R) PC-12 cell model was established. PC-12 cells were transfected and evaluated for viability, cytotoxicity, apoptosis, and autophagy. Inflammatory factors in mouse brain tissues and PC-12 cells were examined via enzyme-linked immunosorbent assay, and related genes were measured via real-time reverse transcriptase-polymerase chain reaction and Western blot. The ring structure of circLOC375190 was assessed by actinomycin-D and RNase-R assays. circRNA targeting to downstream factors was assessed by Fluorescence in situ hybridization assay, dual luciferase reporter assay, and RNA immunoprecipitation assay.

RESULTS

circLOC375190 level was increased in tMCAO mice. Knocking down circLOC375190 reduced infarct size, attenuated cerebral pathological injury and neuronal apoptosis, and inhibited inflammatory damage and autophagy in tMCAO mice. circLOC375190 knockdown enhanced neuronal viability and reduced cytotoxicity, apoptosis, and autophagy in OGD/R-treated PC12 cells. Mechanistically, circLOC375190 acted as a sponge for miR-93-5p to upregulate MAP kinase interacting serine/threonine kinase 2 expression and activate the mechanistic target of rapamycin complex 1/transcription factor EB pathway.

CONCLUSION

circLOC375190 exacerbates tMCAO-mediated neurological injury by regulating neuronal autophagy.

Interplay of cell death pathways and immune responses in ischemic stroke: insights into novel biomarkers

Stroke is a severe neurological disease and a major worldwide issue, mostly manifesting as ischemic stroke (IS). In order to create effective treatments for IS, it is imperative to fully understand the underlying pathologies, as the existing therapeutic choices are inadequate. Recent investigations have shown the complex relationships between several programmed cell death (PCD) pathways, including necroptosis, ferroptosis, and pyroptosis, and their correlation with immune responses during IS. However, this relationship is still unclear. To address this gap, this review study explored the cellular interactions in the immune microenvironment of IS. Then, to validate prior findings and uncover biomarkers, the study investigated bioinformatics studies. Several pathways, including nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), Toll-like receptor 4 (TLR4), and receptor-interacting protein kinase (RIPK), were involved in PCD-immune interactions. The bioinformatics studies reported key biomarkers such as glutathione peroxidase 4 (GPX4), NOD-like receptor family pyrin domain containing 3 (NLRP3), gasdermin D (GSDMD), and TLR4, which have important implications in ferroptosis, cuproptosis, pyroptosis, and necroptosis respectively. These biomarkers were associated with PCD mechanisms such as oxidative stress and inflammatory reactions. The immune infiltration analysis consistently revealed a significant correlation between PCD pathways and detrimental immune cells, such as neutrophils and γδ T cells. Conversely, M2 macrophages and T helper cells showed protective effects. In conclusion, considering the intricate network of interactions between immune responses and PCD pathways, this study emphasized the necessity of a paradigm shift in therapeutic approaches to address the injuries that are related to this complex network.

Circulating circular RNAs as novel biomarkers and functional prediction for the early diagnosis in post-stroke cognitive impairment: A single-center prospective study in China

BACKGROUND

Early evaluation and intervention for post-stroke cognitive impairment are crucial for improving the prognosis of acute ischemic stroke. The search for specific diagnostic markers and feasible therapeutic targets is extremely urgent.The characteristics of circular RNAs make them promising candidates.

AIMS

To screen circular RNAs as novel biomarkers and therapeutic targets for post-stroke cognitive impairment in large-artery atherosclerosis anterior circulation cerebral infarction patients.

METHODS

In this prospective observational study, patients with first-ever large-artery atherosclerosis anterior circulation cerebral infarction were recruited. The Montreal Cognitive Assessment was used to assess the cognitive statuses of patients. Venous blood samples were collected on the seventh day after stroke onset. A circRNA microarray was used to identify differentially expressed circular RNAs in the discovery cohort (four patients with post-stroke cognitive impairment and four patients with post-stroke cognitive normal characteristics), and validation was performed in the validation cohorts (45 patients with post-stroke cognitive impairment and 30 patients with post-stroke cognitive normal characteristics) using quantitative real-time polymerase chain reaction. Receiver operating characteristic curves of the validated circular RNAs and the NIHSS score were constructed, and the area under the curve, sensitivity, and specificity were calculated. Correlation analysis was performed to explore the relationship between the copy number of circular RNAs and the cognitive status. The functions of the differentially expressed circular RNAs were predicted using bioinformatics analysis.

RESULTS

CircRNA microarray analysis revealed 189 human circular RNAs (152 upregulated and 37 downregulated) that were differentially expressed in the plasma samples of patients with post-stroke cognitive impairment and PSCN characteristics. The expression of hsa_circ_0089763, hsa_circ_0064644, and hsa_circ_0089762 was validated using quantitative real-time polymerase chain reaction. The area under the curve, sensitivity, and specificity of hsa_circ_0089762 in post-stroke cognitive impairment diagnosis were 0.993, 97.8%, and 96.7%, respectively, and the correlation coefficient between hsa_circ_0089762 expression and the Montreal Cognitive Assessment score was -0.693 (p < 0.001), which made it an ideal biomarker. Bioinformatic analysis revealed that the targeted mRNAs of the three circular RNAs were enriched in pathologically related signaling pathways of post-stroke cognitive impairment, such as the MAPK and PI3K-Akt signaling pathways. Based on the circRNA-miRNA-mRNA network, the three circular RNAs play a crucial role in numerous pathological processes of acute ischemic stroke and post-stroke cognitive impairment by sponging miRNAs such as MiR-335, MiR-424, and MiR-670. By building the protein-protein interaction network, we identified cluster 1 according to the MCODE score; cluster 1 was composed of ERBB4, FGFR1, CACNA2D1, NRG1, PPP2R5E, CACNB4, CACNB2, CCND1, NTRK2, and PTCH.

CONCLUSION

Hsa_circ_0089762, hsa_circ_0064644, and hsa_circ_0089763 are potential novel biomarkers and focal points for exploring intervention targets in post-stroke cognitive impairment of large-artery atherosclerosis anterior circulation cerebral infarction patients.

REGISTRATION NUMBER

ChiCTR2000035074.

Exosomes as Vehicles for Noncoding RNA in Modulating Inflammation: A Promising Regulatory Approach for Ischemic Stroke and Myocardial Infarction

Exosomes have grown as promising carriers for noncoding RNAs (ncRNAs) in the treatment of inflammation, particularly in conditions like ischemic stroke and myocardial infarction. These ncRNAs, which include microRNAs (miRNAs) and long noncoding RNAs (lncRNAs), play a crucial role in regulating inflammatory pathways, presenting new therapeutic opportunities. In both ischemic stroke and myocardial infarction, inflammation significantly influences disease progression and severity. Exosomes can deliver ncRNAs directly to specific cells and tissues, providing a targeted approach to modulate gene expression and reduce inflammation. Their biocompatibility and low risk of inducing immune responses make exosomes ideal therapeutic vehicles. Ongoing research is focused on optimizing the loading of ncRNAs into exosomes, ensuring efficient delivery, and understanding the mechanisms by which these ncRNAs mitigate inflammation. In ischemic stroke, exosome-derived ncRNAs originate from various cell types, including neurons, M2 microglia, patient serum, genetically engineered HEK293T cells, and mesenchymal stromal cells. In the case of myocardial infarction, these ncRNAs are sourced from mesenchymal stem cells, endothelial cells, and patient plasma. These exosome-loaded ncRNAs play a significant role in modulating inflammation in both ischemic stroke and myocardial infarction. As this research advances, therapies based on exosomes may completely change how diseases linked to inflammation are treated, offering new avenues for patient care and recovery. This review explores the latest advancements in understanding how exosomes impact specific inflammatory components, with a particular emphasis on the role of ncRNAs contained in exosomes. The review concludes by highlighting the clinical potential of exosome-derived ncRNAs as innovative therapeutic and diagnostic tools.

LncRNA RMRP Contributes to the Development and Progression of Spinal Cord Injury by Regulating miR-766-5p/FAM83A Axis

Spinal cord injury (SCI) is known as a central nervous system disorder. Previous studies suggested that long-non-coding RNA RMRP (LncRNA RMRP) was abnormally expressed in SCI, but the potential underlying mechanism remains to be further explored. To explore the regulatory roles of LncRNA RMRP/miR-766-5p/FAM83A axis in SCI. Spinal T9 hemisection was performed on healthy adult male Sprague Dawley (SD) rats to establish the SCI rat models. The expressions of LncRNA RMRP in spinal cord of rats in different groups were examined by RT-qPCR. Moreover, AGE1.HN and PC12 cells were treated with hypoxic condition, and expression of LncRNA RMRP was examined by RT-qPCR methods. Furthermore, hypoxic PC12 cells were transfected with LncRNA RMRP OE, and the cell viability, proliferation, and apoptosis were examined. Next, the direct targeting relationship between LncRNA RMRP and miR-766-5p, as well as miR-766-5p and FAM83A, was confirmed by dual-luciferase reporter and RNA pull-down assays. Finally, the effects of LncRNA RMRP/miR-766-5p/FAM83A axis on cell viability, proliferation, and apoptosis were examined. LncRNA RMRP was downregulated in SCI rats and over-expression of LncRNA RMRP alleviated the SCI condition. LncRNA RMRP over-expression increased the viability and proliferation, and inhibited the apoptosis of hypoxic PC12 cells in vitro. miR-766-5p was confirmed as a target of LncRNA RMRP, and FAM83A was confirmed as a target of miR-766-5p. LncRNA RMRP could regulate the proliferation and apoptosis of hypoxic PC12 cells via regulating miR-766-5p/FAM83A axis in vitro. LncRNA RMRP may contribute to the pathogenesis of SCI via regulating miR-766-5p/FAM83A axis.