HIV-associated neurocognitive disorders (HANDs) afflict more than half of HIV-1-positive individuals. The transactivator of transcription (Tat) produced by HIV virus elicits inflammatory process and is a major neurotoxic mediator that induce neuron damage during HAND pathogenesis. Activated astrocytes are important cells involved in neuroinflammation and neuronal damage. Purinergic receptors expressed in astrocytes participate in a positive feedback loop in virus-induced neurotoxicity. Here, we investigated that whether P2Y4R, a P2Y receptor subtype, that expressed in astrocyte participates in Tat-induced neuronal death in vitro and in vivo. Soluble Tat protein was performed to determine the expression of P2Y4R and proinflammatory cytokines in astrocytes using siRNA technique via real-time PCR, Western blot, and immunofluorescence assays. Cytometric bead array was used to measure proinflammatory cytokine release. The TUNEL staining and MTT cell viability assay were analyzed for HT22 cell apoptosis and viability, and the ApopTag® peroxidase in situ apoptosis detection kit and cresyl violet staining for apoptosis and death of hippocampal neuron in vivo. We found that Tat challenge increased the expression of P2Y4R in astrocytes. P2Y4R signaling in astrocytes was involved in Tat-induced inflammatory cytokine production via PI3K/Akt- and ERK1/2-dependent pathways. Knockdown of P2Y4R expression significantly reduced inflammatory cytokine production and relieved Tat-mediated neuronal apoptosis in vitro. Furthermore, in vivo challenged with Tat, P2Y4R knockdown mice showed decreased inflammation and neuronal damage, especially in hippocampal CA1 region. Our data provide novel insights into astrocyte-mediated neuron damage during HIV-1 infection and suggest a potential therapeutic target for HANDs.

HIV-associated neurocognitive disorder (HAND) is a neurodegenerative disease associated with persistent neuroinflammation and subsequent neuron damage. Pro-inflammatory factors and neurotoxins from activated astrocytes by HIV-1 itself and its encoded proteins, including the negative factor (Nef), are involved in the pathogenesis of HAND. This study was designed to find potential lncRNAs that regulate astrocyte functions and inflammation process. We performed microarray analysis of lncRNAs from primary mouse astrocytes treated with Nef protein. Top ten lncRNAs were validated through real-time PCR analysis. Gene ontology (GO) and KEGG pathway analysis were applied to explore the potential functions of lncRNAs. RIP and ChIP assays were performed to demonstrate the mechanism of lncRNA regulating gene expression. There were 638 co-upregulated lncRNAs and 372 co-downregulated lncRNAs in primary astrocytes treated with Nef protein for both 6 h and 12 h. GO and KEGG pathway analysis showed that the biological functions of top differential-expressed mRNAs were associated with inflammatory cytokines and chemokine. Knockdown of lncRNA AK006025, not AK138360, inhibited significantly CXCL9, CXCL10 (IP-10), and CXCL11 expression in astrocytes treated with Nef protein. Mechanism study showed that AK006025 associated with CBP/P300 was enriched in the promoter of CXCL9, CXCL10, and CXCL11 genes. Our findings uncovered the expression profiles of lncRNAs and mRNAs in vitro, which might help to understand the pathways that regulate astrocyte activation during the process of HAND.

The pro‐inflammatory cytokine interleukin 17 (IL‐17), that is mainly produced by Th17 cells, has been recognized as a key regulator in multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE). Reactive astrocytes stimulated by proinflammatory cytokines including IL‐17 are involved in blood brain barrier destruction, inflammatory cells infiltration and spinal cord injury. However, the role of long non‐coding RNAs (lncRNAs) induced by IL‐17 in the pathogenesis of MS and EAE remains unknown. Herein, we found that an IL‐17‐induced lncRNA AK018453 promoted TGF‐β receptor‐associated protein 1 (TRAP1) expression and Smad‐dependent signaling in mouse primary astrocytes. Knockdown of AK018453 significantly suppressed astrocytosis, attenuated the phosphorylation of Smad2/3, reduced NF‐κB p65 and CBP/P300 binding to the TRAP1 promoter, and diminished pro‐inflammatory cytokine production in the IL‐17‐treated astrocytes. AK018453 knockdown in astrocytes by a lentiviral vector in vivo dramatically inhibited inflammation and prevented the mice from demyelination in the spinal cord during the progression of EAE. Together, these results suggest that AK018453 regulates IL‐17‐dependent inflammatory response in reactive astrocytes and potentially promotes the pathogenesis of EAE via the TRAP1/Smad pathway. Targeting this pathway may have a therapeutic potential for intervening inflammatory demyelinating diseases.

To construct a lentiviral vector expressing HIV-1 Tat and identify its expression in 293T cells. The gene fragment of HIV-1 Tat101 was subcloned to lentiviral transfer vector pHAGE-CMV-MCS-IZsGreen, which was named pHAGE-Tat. Then the constructed pHAGE-Tat was used to co-transfect the packing 293T cells, together with the packaging plasmids pMD2.G and psPAX2. The packaged viral particles designated LV-Tat were used to infect the 293T cells and the viral titer was calculated. The expression of HIV-1 Tat in 293T cells was confirmed using RT-PCR and western blot. The recombinant lentiviral vector was successfully constructed and could express HIV-1 Tat in 293T cells. The virus titer was 5.73×10(6) ifu/ml. The successfully constructed recombinant lentiviral vector makes a strong foundation for further exploring the possible role of HIV-1 Tat in the development of prostate cancer.

N6-methyladenosine (m⁶A) is the most abundant internal RNA modification in eukaryotes and plays a critical role in gene expression regulation by influencing RNA stability, splicing, nuclear export, and translation. Emerging evidence suggests that dysregulation of m⁶A contributes to neuroinflammation, neurotoxicity, and synaptic dysfunction—key features of neurodegenerative diseases. This review aims to examine the role of m6A modification in neurodegenerative diseases from a cell-type-specific perspective. We systematically reviewed recent studies investigating m⁶A modifications in neurons and glial cells. Data from transcriptomic, epitranscriptomic, and functional studies were analyzed to understand how m⁶A dynamics influence disease-related processes. Findings indicate that m⁶A modifications regulate neuroinflammation and immune responses in microglia, modulate astrocytic support functions, affect myelination through oligodendrocytes, and alter m⁶A patterns in neurons, impacting synaptic plasticity, stress responses, and neuronal survival. These cell-type-specific roles of m⁶A contribute to the progression of neurodegenerative diseases such as Alzheimer’s disease (AD), Parkinson’s disease (PD), and Amyotrophic lateral sclerosis (ALS). Understanding m⁶A-modulated mechanisms in specific neural cell types may facilitate the development of targeted interventions for neurodegenerative diseases.