TL;DR
Serum DLX6-AS1 is a potential biomarker for early diagnosis and assessment of AD, and regulates Aβ-induced neuronal damage and tau phosphorylation by targeting miR-204-5p, offering a new mechanism target for AD molecular therapy.
Alzheimer’s Disease (AD) is a progressive neurodegenerative disorder characterized by complex and not yet fully understood pathological mechanisms. This study was designed to explore the molecular mechanisms of long non-coding RNA (lncRNA) FBXL19-AS1 in the pathological progression of AD. 110 AD patients and 110 healthy controls were recruited for this study. Relevant gene expression was measured using reverse transcription quantitative real-time PCR (RT-qPCR), and the diagnostic performance was assessed through receiver operating characteristic (ROC) curve analysis. AD cell models were established by treating SH-SY5Y and BV2 cells with amyloid β (Aβ)25–35. Cell proliferation was evaluated using the cell counting kit-8 (CCK-8) assay, cell apoptosis was analyzed by flow cytometry, and the secretion levels of inflammatory factors were determined via enzyme-linked immunosorbent assay (ELISA). A dual-luciferase reporter assay was performed to confirm the direct regulatory interactions. In AD patients, the FBXL19-AS1 and integrin subunit beta 3 (ITGB3) expression were significantly elevated, whereas microRNA-650 (miR-650) expression was markedly reduced. FBXL19-AS1 showed certain diagnostic potential for AD, and its expression was negatively correlated with Montreal Cognitive Assessment (MoCA) scores. Following treatment with Aβ25–35, SH-SY5Y cells exhibited reduced proliferative capacity and increased apoptosis, while BV2 cells showed elevated levels of inflammatory factors. Additionally, Aβ25–35 treatment led to upregulated expression of FBXL19-AS1 and ITGB3, along with downregulated expression of miR-650. Knockdown of FBXL19-AS1 effectively reversed these effects. However, inhibition of miR-650 partially attenuated the changes induced by FBXL19-AS1 knockdown. Furthermore, knockdown of FBXL19-AS1 markedly reduced ITGB3 expression, whereas concurrent inhibition of miR-650 partially reversed this downregulatory effect. FBXL19-AS1 appears to interact with and modulate miR-650, thereby affecting ITGB3 expression and potentially participating in the pathological progression of AD.
Neuroinflammation assumes a pivotal role in Alzheimer's disease (AD) pathogenesis. Long noncoding RNAs (lncRNAs) regulate neuroinflammation through a competitive endogenous RNA (ceRNA) mechanism. This study aimed to explore the mechanism of SNHG3/miR-128-3p/UBR5 axis in AD associated neuroinflammation. SNHG3, miR-128-3p, and UBR5 levels were recognized by reverse transcription - quantitative polymerase chain reaction (RT-qPCR). In vitro AD model was established by Aβ1-42 stimulation in human microglial cells HMC3 and neuronal cells SK‑N‑SH. Cell apoptosis was detected by flow cytometry. Enzyme - linked immunosorbent assay (ELISA) and oxidative stress indicators were used to evaluate the neuroinflammatory phenotype. Morris water maze (MWM) test assesses the spatial learning and memory abilities of amyloid precursor protein/presenilin 1 (APP/PS1) mice with AAV-si-SNHG3. Serum SNHG3 was clearly upregulated in AD patients, and negatively related to MMSE score (r = -0.691, P<0.001). SNHG3 had diagnostic potential for AD (AUC=0.847, 95% CI = 0.806-0.888, sensitivity=75.63%, specificity=76.88%). SNHG3 regulates UBR5 expression by sponges miR-128-3p. Silence of SNHG3 inhibited M1 polarization (reducing TNF-α, IL-6, and iNOS), promotes M2 polarization (increasing Arg1, IL-10, and TGF-β), inhibits IL-1β release, suppresses neuronal apoptosis, and mitigates oxidative stress damage (reducing MDA and increasing SOD) via miR-128-3p/UBR5 axis in Aβ-stimulated HMC3 cells. SNHG3 also contributes to Aβ‑induced neuronal apoptosis, inflammation, and oxidative stress in SK‑N‑SH cells. AAV-si-SNHG3 significantly enhances spatial learning and memory abilities of APP/PS1 mice, and inhibits neuroinflammation and oxidative stress in the hippocampus. This study is the first to elucidate that SNHG3 could regulate microglial polarization and neuroinflammation through the SNHG3/miR-128-3p/UBR5 axis.
OBJECTIVE This study aims to investigate the expression pattern of long noncoding RNA SNHG16 in pediatric temporal lobe epilepsy (TLE), its clinical diagnostic value, and its molecular mechanisms in epilepsy-related neuronal damage. METHODS This study included 78 newly diagnosed pediatric TLE patients and 75 healthy control children. SNHG16 expression was detected via RT-qPCR, and its diagnostic efficacy was evaluated using ROC curves. In vitro, a TLE model was established in human hippocampal neuronal cells treated with magnesium-free medium. Cell viability, apoptosis, inflammatory factor levels (IL-6, IL-1β, TNF-α), and oxidative stress markers (SOD, GSH, MDA) were assessed using MTT assay, flow cytometry, ELISA, and biochemical kits, respectively. The targeting relationship between SNHG16 and miR-485-5p was validated through dual-luciferase reporter assays and RIP experiments. RESULTS Serum SNHG16 expression was significantly upregulated in TLE pediatric patients, with an area under the curve (AUC) of 0.895. In cell models, silencing SNHG16 significantly alleviated magnesium-deprivation-induced decreases in cell viability, increased apoptosis, oxidative stress, and inflammatory responses. Mechanistically, SNHG16 directly binds and negatively regulates miR-485-5p expression in the cytoplasm. Inhibiting miR-485-5p reversed the neuroprotective effects induced by SNHG16 knockdown. CONCLUSION SNHG16 is highly expressed in pediatric TLE and has certain diagnostic potential. It exacerbates epilepsy-related neuronal damage by binding to and suppressing miR-485-5p function. This study provides novel insights into understanding the disease mechanism.
BACKGROUND MicroRNAs (miRNAs) have emerged as critical modulators in Alzheimer's disease (AD) pathogenesis. The lethal-7 (let-7) family functions as key regulators of cell apoptosis, differentiation, and immune response. Herein, we explore the functions and underlying mechanisms of let-7d-5p in AD progression. METHODS Eight-month-old male APP/PS1 transgenic mice and wild-type C57BL/6 J mice were assigned to the model and control groups, respectively. Model mice received intrahippocampal injections of either a negative control adenovirus (Ad-NC) or a let-7d-5p overexpression adenovirus (Ad-let-7d-5p). The Morris water maze test was conducted to assess cognitive function. Hippocampal histopathological changes were evaluated using hematoxylin and eosin staining. Aβ deposition was detected via immunohistochemical staining. SH-SY5Y cells were transfected with let-7d-5p mimics prior to treatment with 10 μM Aβ1-42. Cell viability and apoptosis were examined using MTT assays and flow cytometry. The expression levels of let-7d-5p and bach1 were measured using RT-qPCR. Western blotting was conducted to evaluate bach1, Bcl-2, and cleaved caspase-3 protein levels. The binding relationship between let-7d-5p and bach1 was verified using luciferase reporter assays. RESULTS In vitro, Aβ1-42 treatment induced the downregulation of let-7d-5p and decrease of cell viability. However, overexpression of let-7d-5p significantly increased let-7d-5p level, enhanced cell viability and inhibited cell apoptosis of Aβ1-42-treated SH-SY5Y cells. Moreover, overexpression of let-7d-5p upregulated Bcl-2 protein levels and downregulated cleaved caspase-3 protein levels in Aβ1-42-treated SH-SY5Y cells. Furthermore, let-7d-5p overexpression ameliorated oxidative stress injury in Aβ1-42-treated SH-SY5Y cells. Importantly, bach1 upregulation counteracted the inhibitory effects of let-7d-5p overexpression on Aβ1-42-induced cellular injury. In vivo, let-7d-5p overexpression mitigated cognitive deficits of AD mice, as indicated by reduced escape latency and increased platform crossings. Additionally, let-7d-5p overexpression attenuated hippocampal histopathological changes and Aβ deposition in APP/PS1 mice. At the molecular level, let-7d-5p targeted bach1 3'UTR and repressed its mRNA and protein expression in vitro and in vivo. Rescue assays further validated that bach1 overexpression restored the protective effect of let-7d-5p on cognitive deficits and pathological injuries. CONCLUSION Let-7d-5p alleviates cognitive deficits in AD by inhibiting Aβ deposition and neuronal apoptosis through targeting bach1.
Alzheimer’s disease (AD) is a progressive neurodegenerative disorder presenting memory loss, cognitive decline, synaptic dysfunction and irreparable neuronal damage. It is the most common dementia disorder in the world, and a major public health problem. Although much research has been done into this, no pharmacologic treatments yet exist that can effectively prevent or reverse disease progression and only offer symptomatic relief. The purinergic P2X7 receptor and the subsequent NLRP3 inflammasome signaling pathway have well established as key players in the regulation of neuro-inflammatory responses in AD. Extracellular ATP binding to the P2X7 receptor leads to assembly of the NLRP3 inflammasome complex. Caspase-1 activation and further increase in the production of pro-inflammatory cytokines like interleukin-1 beta (IL-1β) and interleukin-18 (IL-18), speed up the injury of neurons and disease progression. As a natural alternative remedy, medicinal plants with multi-target pharmacological activities have been an object of special interest for the treatment of AD. Dalbergia sissoo Roxb. Sheesham is a common medicinal tree of the Fabaceae family that has been traditionally utilized for inflammatory, neurological and oxidative stress disorders. Plant have shown the presence of various bioactive compounds such as flavonoids and phenolic compounds, with notable antioxidant, anti-inflammatory and neuroprotective effects. The therapeutic properties of Dalbergia sissoo can be linked to its anti-oxidative properties, down-regulation of pro-inflammatory cytokines and protection of neuronal cells from inflammatory damage. Recently increases of its phytochemical ingredients may affect ATP-mediated activation of P2X7 receptor and inhibition of NLRP3 inflammasome signalling in Alzheimer’s disease. The present review aims to delve into the potential mechanism of action of Dalbergia sissoo in Alzheimer’s disease (AD), focusing on the interaction between the P2X7 receptor and NLRP3 inflammasome.
