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Jury, D.

Publications and source records attributed to Jury, D..

4 recordsLinked to original sources

MiR-23b Neutralization In Brain Endothelium Promotes Blood-Brain Barrier Repair Through Wnt/Beta-catenin Dependent And Independent Mechanisms

Blood-brain barrier (BBB) disruption drives stroke and other CNS disorders pathology, yet restoring its integrity remains challenging. Using an unbiased anti-miR lentiviral screen, miR-23b was identified as a critical negative regulator of BBB integrity in brain endothelial cells (BECs). Targeted inhibition of miR-23b using anti-miR-23b, validated by Wnt-reporter, Wnt-rescue, and eCLIP analysis, demonstrates that BEC miR-23b silencing in BECs, enhances junctional protein expression and strengthens barrier function while suppressing transcellular transport. Global multi-omics analysis reveals that miR-23b acts as a robust driver of angiogenesis-specific genes and proteins. Conversely, anti-miR-23b induces the expression of factors essential for BBB stabilization and repair. Notably, anti-miR-23b enhances these protective barrier properties through the multi-faceted regulation of Wnt/{beta}-catenin, TGF-{beta}, Notch, and VEGF signaling mechanisms. Using a 3D microfluidic platform, anti-miR-23b was shown to foster BBB repair by accelerating vessel maturation and enhancing resilience against ischemic injury. Proof-of-concept studies show that BEC specific AAVBR1-anti-miR-23b gene therapy reinforces BBB tight junctions, reduces BBB leakage, and improves outcome measures in a transient middle cerebral artery occlusion (t-MCAO) stroke model. Thus, miR-23b is a critical regulator of cerebrovascular integrity, positioning anti-miR-23b as a promising RNA-based therapy to enhance BBB stability and repair in stroke and other CNS disorders.

neuroscience↗

The Role of Paraventricular Nucleus of Thalamus in Sleep Disturbance Induced by Withdrawal from Repeated Ethanol Exposure

Sleep disturbance is known to be comorbid with withdrawal from repeated ethanol exposure and could be a negative reinforcement for the majority of people with alcohol use disorder (AUD). The paraventricular nucleus of the thalamus (PVT) has been highlighted for its function in integrating arousal states and associated modulation in sleep homeostasis. However, there is limited understanding of the involvement of PVT neurons in regulating sleep patterns, especially during withdrawal from chronic ethanol exposure. In this study, we investigated the potential function of the PVT in sleep disturbance during ethanol withdrawal using electrophysiology, in vivo calcium imaging, biochemical, and chemogenetic approaches. At 24 hours post-withdrawal from chronic intermittent ethanol exposure (CIE) for four weeks, there is an increase in wake time and a decrease in non-rapid eye movement (NREM) sleep. The calcium transient levels in the PVT neurons are positively correlated with the transition from sleep to wakefulness. CIE elevates the PVT neuronal activity in a subregion-specific manner, resulting in a significant rise in cFos levels in the anterior PVT (aPVT). Temporal suppression of aPVT excitatory neurons via chemogenetics ameliorates the disturbance in sleep patterns generated by CIE. The aPVT has a notable distinction in the expression of the m-type potassium channel subunit, KCNQ2, with a higher expression level compared to the posterior PVT (pPVT). While the expression of KCNQ2 in the aPVT is reduced in CIE mice, the restoration of KCNQ2 expression using viral gene transfer within the aPVT alleviates the sleep disturbances produced by CIE. This data indicates a significant role of the PVT in sleep disturbance during ethanol withdrawal, which may partially be due to the downregulation of M-channels, hence underscoring M-channels in the PVT as a potential therapeutic target for sleep disturbance in alcohol use disorder.

neuroscience↗

miR-128 inhibits telomerase activity by targeting TERT mRNA

Telomerase is a unique cellular reverse transcriptase essential for maintaining telomere stability and required for the unlimited proliferation of cancer cells. The limiting determinant of telomerase activity is the catalytic component TERT, and TERT expression is closely correlated with telomerase activity and cancer initiation and disease progression. For this reason the regulation of TERT levels in the cell is of great importance. microRNAs (miRs) function as an additional regulatory level in cells, crucial for defining expression boundaries, proper cell fate decisions, cell cycle control, genome integrity, cell death and metastasis. We performed an anti-miR library screen to identity novel miRs, which participate in the control of telomerase. We identified the tumor suppressor miR (miR-128) as a novel endogenous telomerase inhibitor and determined that miR-128 significantly reduces the mRNA and protein levels of Tert in a panel of cancer cell lines. We further evaluated the mechanism by which miR-128 regulates TERT and demonstrated that miR-128 interacts directly with the coding sequence of TERT mRNA in both HeLa cells and teratoma cells. Interestingly, the functional miR-128 binding site in TERT mRNA, is conserved between TERT and the other cellular reverse transcriptase encoded by Long Interspaced Elements-1 (LINE-1 or L1), which can also contribute to the oncogenic phenotype of cancer. This finding supports the novel idea that miRs may function in parallel pathways to inhibit tumorigenesis, by regulating a group of enzymes (RT) by targeting conserved binding sites in the coding region of both enzymes.\n\nNOVELTY AND IMPACTTelomerase is an RNA-dependent DNA polymerase that synthesizes telomeric DNA sequences and almost universally provides the molecular basis for unlimited proliferative potential. Expression of human telomerase alone is sufficient for the immortalization of diverse cell types. We have identified the tumor suppressor microRNA (miR-128) as a novel regulator of telomerase, which directly targets the coding sequence (CDS) of TERT mRNA and significantly represses Tert protein expression in a panel of cancer cell lines.

cancer biology↗

miR-128-induced LINE-1 restriction is dependent on down-regulation of hnRNPA1

The majority of the human genome is made of transposable elements, giving rise to interspaced repeats, including Long Interspersed Element-1s (LINE-1s or L1s). L1s are active human DNA parasites involved in genomic diversity and evolution, but can also contribute to genomic instability and diseases. L1s require host factors to complete their life cycles, whereas the host has evolved numerous mechanisms to restrict L1-induced mutagenesis. Restriction mechanisms in somatic cells include methylation of the L1 promoter, anti-viral factors and RNA-mediated processes such as small RNAs. microRNAs (miRNAs or miRs) are small non-coding RNAs that post-transcriptionally repress multiple target genes often found in the same cellular pathways. We have recently established that the interferon-inducible miR-128 function as a novel restriction factor inhibiting L1 mobilization in somatic cells. We have further demonstrated that miR-128 function through a dual mechanism; by directly targeting L1 RNA for degradation and indirectly by inhibiting a cellular co-factor which L1 is dependent on to transpose to new genomic locations (TNPO1). Here we add another piece to the puzzle of the enigmatic L1 life cycle. We show that miR-128 also inhibits another key cellular factor, hnRNPA1, by significantly reducing mRNA and protein levels through direct interaction with the coding sequence (CDS) of hnRNPA1 mRNA. Furthermore, we demonstrate that repression of hnRNPA1 using shRNA significantly decreases de novo L1 retrotransposition and that induced hnRNPA1 expression enhances L1 mobilization. Finally, we determine that hnRNPA1 is a functional target of miR-128 and that induced hnRNPA1 expression in miR-128-overexpressing cells can partly rescue the miR-128-induced repression of L1s ability to transpose to different genomic locations. Thus, we have identified an additional mechanism by which miR-128 represses L1 retrotransposition and mediate genomic stability.

cell biology↗