Biomedical subjects

Han Yan

Publications and source records attributed to Han Yan.

3 recordsLinked to original sources

PubMed2026

The miR-206-3p/Cpeb1 axis delays acetylcholine receptor degradation and preserves neuromuscular junction stability in denervation-induced muscle atrophy.

Peripheral nerve injury leads to progressive neuromuscular junction (NMJ) destabilization and acetylcholine receptor (AChR) degradation, which are critical drivers of denervation-induced muscle atrophy and impaired motor recovery. However, the post-transcriptional mechanisms regulating AChR stability during denervation remain poorly understood. Here, we investigated the role of miR-206-3p in NMJ maintenance and muscle preservation after denervation, with a focus on its interaction with the RNA-binding protein cytoplasmic polyadenylation element binding protein 1 (Cpeb1). Using C2C12 myoblasts and a sciatic nerve transection mouse model, we demonstrate that miR-206-3p promotes myogenic differentiation, enhances AChR clustering, and preserves postsynaptic AChR morphology. miR-206-3p directly targets the 3' untranslated region of Cpeb1, suppressing its expression, as confirmed by dual-luciferase reporter assays. In vivo, adeno-associated virus-mediated overexpression of miR-206-3p delayed denervation-induced AChR fragmentation, attenuated muscle atrophy, and significantly improved motor function recovery. Conversely, Cpeb1 overexpression accelerated AChR degradation and muscle wasting, whereas co-overexpression of miR-206-3p mitigated these detrimental effects, indicating that Cpeb1 is a key downstream effector of miR-206-3p. Collectively, our findings identify the miR-206-3p/Cpeb1 axis as a previously unrecognized regulator of NMJ stability and muscle integrity after denervation, providing mechanistic insight and a potential therapeutic target for preserving neuromuscular function during prolonged denervation.

Animals↗

PubMed2026

Clinical outcomes of fusion vs excision in the treatment of painful type II accessory naviculars: A matched cohort study.

BACKGROUND: For painful Type II accessory naviculars, whether to remove or fuse them remains unclear based on the current literature. This study aimed to investigate the clinical outcomes of fusion versus excision in treating painful type II accessory naviculars. METHODS: This retrospective comparative study included and followed 54 eligible patients (from May 2017 to March 2023). After 1:1 propensity score matching (PSM), 34 patients (17 fusion versus 17 excision) were analyzed. Outcomes included Visual Analog Scale (VAS), American Orthopaedic Foot and Ankle Society (AOFAS) midfoot score, Tegner score, complication rates, and radiographic measurements. Receiver operating characteristic (ROC) curve analysis was performed to identify the appropriate accessory navicular size cutoff for predicting nonunion following fusion. RESULTS: The mean follow-up was 35.0 ± 9.9 months. The fusion and excision groups showed significant and comparable VAS and AOFAS score improvements (p < .001). The fusion group had a higher complication rate (41.2% vs. 5.9%, p = .039), primarily nonunion and persistent pain. ROC curve analysis identified 50.3 mm² as the cutoff for nonunion risk; sizes < 50.3 mm² predicted high nonunion likelihood. CONCLUSIONS: Both fusion and excision are effective treatments for painful type II accessory naviculars, demonstrating acceptable pain and functional improvement during midterm follow-up. However, the lower complication rate along with relatively superior functional recovery favors the excision technique. For accessory naviculars smaller than 50.3 mm2, excision may be a better choice. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Humans↗

PubMed2025

The mRNA export pathway licenses viral mimicry response and antitumor immunity by actively exporting nuclear retroelement transcripts.

Nuclear retroelement transcripts (RTs), which can be elicited both transcriptionally and posttranscriptionally, form double-stranded RNA (dsRNA) in cytosol to trigger the viral mimicry response (VMR) and antitumor immunity. However, the strength of the induced VMR varies tremendously across tumor types, and the underlying mechanisms remain poorly understood. Here, we demonstrate that the mRNA export pathway modulates the VMR through actively exporting nuclear RTs for cytosolic dsRNA formation after their induction. Tumor cells hijack this process for immune evasion through aberrant coactivator-associated arginine methyltransferase 1 (CARM1) expression. Mechanistically, we show that the cytoplasmic transportation of RTs by the mRNA export pathway is counteracted by the RNA exosome, which cleaves multiple transcripts within this pathway, including those encoding the essential DExD-box helicase 39A (DDX39A) and the adaptor protein ALYREF. CARM1 enhances the RNA exosome activity to attenuate the nuclear export of RTs by the mRNA export pathway through two synergistic mechanisms: (i) transcriptionally activating several RNA exosome components and (ii) posttranslationally methylating arginine 6 of the RNA exosome subunit EXOSC1, which protects it from proteasome-mediated degradation. Collectively, our study highlights the critical active regulatory role of the mRNA export pathway in transporting nuclear RTs into the cytosol for triggering the VMR and tumor immunity. Furthermore, we propose that enhancing the mRNA export pathway activity, either through CARM1 inhibition or RNA exosome modulation, could reinforce the therapeutic agent-induced VMR, thus holding the promise for overcoming tumor immune evasion and immunotherapy resistance.

Humans↗