MiR-203a-3p attenuates apoptosis and pyroptosis of chondrocytes by regulating the MYD88/NF-κB pathway to alleviate osteoarthritis progression.

BACKGROUND: Osteoarthritis (OA) is a degenerative joint disease that imposes a significant socioeconomic burden worldwide. Our previous studies revealed a down-regulation of miR-203a-3p in the knee tissues of OA patients. However, the underlying mechanism through which miR-203a-3p mediates the pathological process of OA remains unknown. Thus, we aimed to determine the effects of miR-203a-3p in the progression of OA. METHODS: Rat primary chondrocytes were stimulated with 10 µg/mL lipopolysaccharide (LPS) for 24 hours, followed by transfection with 50 nM miR-203a-3p mimic, inhibitor, and siRNA for MYD88 or consistent negative controls for 48 hours. To evaluate the effects of miR-203a-3p on cartilage matrix degradation, oxidative stress, apoptosis, and pyroptosis in chondrocytes, various techniques such as immunofluorescence staining, biochemical analysis, Western blotting, and the TUNEL staining were utilized. In the rat OA model, all rats were randomly divided into four groups: Sham, OA, OA+Agomir negative control (NC), and OA+Agomir. They received intra-articular injections of 25 nmol miR-203a-3p agomir, agomir NC, or normal saline twice a week for the duration of 8 weeks after OA induction. Immunofluorescence staining was performed to evaluate the effects of miR-203a-3p on cartilage matrix degradation in rats. RESULTS: MiR-203a-3p was down-regulated in LPS-treated rat chondrocytes and OA cartilage, and directly targeted MYD88. Moreover, miR-203a-3p significantly inhibited LPS-induced cartilage matrix degradation, oxidative stress, apoptosis, and pyroptosis of chondrocytes via targeting MYD88. Mechanistically, miR-203a-3p exerted protective effects via the inhibition of the MYD88/NF-κB pathway. In the rat OA model, intra-articular injections of miR-203a-3p agomir also significantly inhibited cartilage matrix degradation, thereby alleviating OA progression. Furthermore, the miR-203a-3p agomir-treated arthritic rat dramatically exhibited better articular tissue morphology and lower OARSI scores. CONCLUSIONS: MiR-203a-3p plays a role in alleviating the progression of OA by regulating the MYD88/NF-κB pathway, thereby inhibiting cartilage matrix degradation, oxidative stress, apoptosis, and pyroptosis of chondrocytes. It highlights the potential significance of miR-203a-3p as an important regulator of OA.

Thrombus Enhancement Sign May Differentiate Embolism From Arteriosclerosis-Related Large Vessel Occlusion.

BACKGROUND AND PURPOSE: To evaluate whether the thrombus enhancement sign (TES) can be used to differentiate embolic large vessel occlusion (LVO) from in situ intracranial atherosclerotic stenosis (ICAS)-related LVO in the anterior circulation of patients with acute ischemic stroke (AIS). METHODS: Patients with LVO in the anterior circulation who underwent both non-contrast computed tomography (CT) and CT angiography and mechanical thrombectomy were retrospectively enrolled. Both embolic LVO (embo-LVO) and in situ ICAS-related LVO (ICAS-LVO) were confirmed by two neurointerventional radiologists after reviewing the medical and imaging data. TES was assessed to predict embo-LVO or ICAS-LVO. The associations between occlusion type and TES, along with clinical and interventional parameters, were investigated using logistic regression analysis and a receiver operating characteristic curve. RESULTS: A total of 288 patients with AIS were included and divided into an embo-LVO group (n=235) and an ICAS-LVO group (n=53). TES was identified in 205 (71.2%) patients and was more frequently observed in those with embo-LVO, with a sensitivity of 83.8%, specificity of 84.9%, and area under the curve (AUC) of 0.844. Multivariate analysis showed that TES (odds ratio [OR], 22.2; 95% confidence interval [CI], 9.4-53.8; P<0.001) and atrial fibrillation (OR, 6.6; 95% CI, 2.8-15.8; P<0.001) were independent predictors of embolic occlusion. A predictive model that included both TES and atrial fibrillation yielded a higher diagnostic ability for embo-LVO, with an AUC of 0.899. CONCLUSION: TES is an imaging marker with high predictive value for identifying embo- and ICAS-LVO in AIS and provides guidance for endovascular reperfusion therapy.