ObjectiveTo investigate the mechanism through which miR‑21 improves chronic renal fibrosis in mice via targeted modulation of the phosphatase and tensin homolog （PTEN）/protein kinase B （AKT）/mammalian target of rapamycin （mTOR） pathway. MethodsThirty‑two chronic kidney disease model mice were randomly divided into four groups （n=8 each group）： model group， miR‑21 overexpression group， miR‑21 inhibition group， and miR‑21 inhibition + MK‑2206 group. Eight healthy mice were included as the control group. The miR‑21 overexpression， miR‑21 inhibition， and miR‑21 inhibition + MK‑2206 groups received tail‑vein injections of lentivirus （50 μL， 1×10⁸ TU per mouse） once weekly for three weeks. The control and model groups were injected with an equal volume of empty vector （LV‑NC）. The miR‑21 inhibition + MK‑2206 group additionally received gavage of the AKT/mTOR pathway inhibitor MK‑2206 （480 mg/kg） once weekly for three weeks. The expressions of miR‑21， 24 h urinary protein， serum creatinine （Scr）， blood urea nitrogen （BUN）， and renal tissue levels of collagen Ⅰ， collagen Ⅲ， α‑smooth muscle actin （α‑SMA）， and PTEN protein， as well as p‑AKT/AKT and p‑mTOR/mTOR ratios， were compared among groups. HE staining was used to observe pathological changes in renal tissue， and Masson staining was used to observe the degree of renal fibrosis. A dual‑luciferase assay was performed to verify the targeting relationship between miR‑21 and PTEN. ResultsCompared with the model group， miR‑21 expression in renal tissue increased in the miR‑21 overexpression group （P<0.05） and decreased in the miR‑21 inhibition group （P<0.05）. Compared with the model group， the miR‑21 overexpression group showed increased 24 h urinary protein， Scr， BUN， and renal tissue expression of collagen Ⅰ， collagen Ⅲ， and α‑SMA （all P<0.05）， while these indicators decreased in the miR‑21 inhibition group （P<0.05）. Compared with the miR‑21 inhibition group， the miR‑21 inhibition + MK‑2206 group exhibited lower 24‑h urinary protein， Scr， BUN， and renal tissue expression of Collagen Ⅰ， Collagen Ⅲ， and α‑SMA （all P<0.05）. Compared with the model group， the miR‑21 overexpression group showed decreased PTEN protein expression （P<0.05） and increased p‑AKT/AKT and p‑mTOR/mTOR ratios （P<0.05）， while the miR‑21 inhibition group showed increased PTEN expression （P<0.05） and decreased p‑AKT/AKT and p‑mTOR/mTOR ratios （P<0.05）. Compared with the miR‑21 inhibition group， the miR‑21 inhibition + MK‑2206 group had lower p‑AKT/AKT and p‑mTOR/mTOR ratios （P<0.05）， with no significant difference in PTEN protein expression. HE and Masson staining showed normal kidney structure and almost no fibrosis in the control group. The model group exhibited glomerular enlargement， capillary loop adhesion， and focal fibrosis. The miR-21 overexpression group showed severe destruction of glomerular structure， accompanied by extensive fibrosis and renal tubular atrophy. The pathological changes and degree of fibrosis were alleviated in the miR-21 inhibition group. The miR-21 inhibition + MK-2206 group showed only mild pathological changes and mild fibrosis， with the interstitium being largely normal. Compared with PTEN-WT + NC mimics 1， the relative luciferase activity in the PTEN-WT + miR-21 mimics group decreased （P<0.001）. There was no statistically significant difference in relative luciferase activity between PTEN-WT + NC mimics group and PTEN-MUT + miR-21 mimics group. ConclusionmiR‑21 may improve renal function indicators and alleviate renal fibrosis in chronic kidney disease mice via targeted modulation of PTEN and subsequently inhibiting the AKT/mTOR pathway.

Objective To identify potential immunosenescence markers in benign prostatic hyperplasia(BPH)and to explore BPH-related senescent phenotypes. Methods Three transcriptome datasets and one single-cell RNA-sequencing(scRNA-seq)dataset for BPH and normal prostate tissues were obtained from the Gene Expression Omnibus(GEO)database. The GSE7307 and GSE119195 were combined to analyze differentially expressed genes(DEGs). Enrichment analysis and immune infiltration analysis were used to explore aging-related changes in the immune microenvironment. Weighted gene coexpression network analysis(WGCNA)was applied to identify immune-related genes in GSE132714. ScRNA-seq data were employed to investigate the transcriptomic landscape, luminal cell heterogeneity, and aging-related alterations in BPH through cell-cell communication and pseudotime analysis. Finally, the results were validated with in vitro experiments. Results A total of 1202 DEGs and 627 immune-related genes were identified in BPH and normal prostate tissues. Enrichment analysis indicated that the vascular endothelial growth factor(VEGF)signaling pathway exhibited a downregulated aging phenotype in BPH. In scRNA-seq analysis, 9 cell types were identified. The VEGF signaling pathway in BPH exhibited an aging-related expression pattern, characterized by decreased vascular endothelial growth factor A(VEGFA)in luminal cells. Conclusion Our study identified VEGFA as a marker of immunosenescence in BPH, with changes of the VEGF pathway. Meanwhile, low expression of VEGFA, coupled with high expression of placental growth factor(PlGF)and vascular endothelial growth factor receptor(VEGFR), represented a senescent phenotype of the prostate.

Spermatogenesis is a highly ordered and spatiotemporally regulated developmental process in the male reproductive system, during which spermatogonial stem cells (SSCs), supported by the seminiferous tubule microenvironment, sequentially undergo mitosis, meiosis, and spermiogenesis to ultimately generate structurally intact spermatozoa. This complex process is accompanied by extensive transcriptional reprogramming, chromatin remodeling, and finely tuned post-transcriptional regulation. Precise control of RNA fate is therefore essential for maintaining the continuity and fidelity of spermatogenesis, and its disruption represents a major molecular basis of male infertility. N⁶-methyladenosine (m⁶A), the most abundant internal RNA modification in eukaryotes, has emerged as a critical regulator of post-transcriptional gene expression. m⁶A methyltransferases (“writers”) catalyze the addition of a methyl group to the N⁶ position of adenosine, m⁶A demethylases (“erasers”) remove the modification, and m⁶A-binding proteins (“readers”) recognize m⁶A-modified transcripts. Through the coordinated actions of these factors, m⁶A regulates transcript fate at multiple levels, including RNA splicing, nuclear export, stability, translation, and decay. Emerging evidence indicates that m⁶A-mediated regulation is essential across multiple stages of spermatogenesis, including SSC self-renewal and differentiation, meiotic progression, maintenance of chromosomal stability, and sperm morphogenesis. Beyond its intrinsic functions in germ cells, m⁶A also contributes to the regulation of the testicular microenvironment. In sertoli cells, m⁶A is involved in maintaining blood-testis barrier integrity, RNA processing, and paracrine signaling, thereby providing structural and metabolic support for germ cell development. In Leydig cells, m⁶A regulates steroidogenesis, particularly testosterone synthesis, and participates in cellular stress responses and metabolic homeostasis. Through these mechanisms, m⁶A indirectly influences spermatogenesis by modulating the functional state of testicular somatic cells, highlighting an integrated regulatory mode that combines cell-intrinsic and microenvironment-mediated effects. Notably, distinct classes of m⁶A regulators exhibit pronounced stage-specific functions and coordinated division of labor, collectively forming a multilayered and dynamic regulatory network. Writers often display dosage- and temporal window-dependent effects; erasers contribute to stage-specific demethylation and functional compensation; while readers function through a “switch-buffer” dual-layer architecture, and RNA-binding proteins (RBPs) participate in substrate selection and post-transcriptional regulation. Importantly, emerging evidence suggests that some m⁶A-related proteins can function through noncanonical mechanisms independent of m⁶A recognition, such as intrinsic RNA-binding activity, helicase function, or ribonucleoprotein complex assembly, thereby expanding the functional landscape of the m⁶A regulatory system. Dysregulation of m⁶A machinery can lead to multiple spermatogenic defects, including impaired SSC self-renewal, meiotic arrest, abnormal chromatin remodeling, and defective sperm formation, ultimately resulting in male infertility. Despite substantial advances, several critical questions remain unresolved, including the distinction between m⁶A-dependent and -independent mechanisms, the spatiotemporal dynamics of m⁶A modifications at single-cell resolution, and the coordination and antagonism among different regulatory factors. In this review, we systematically summarize the dual regulation of spermatogenesis by germ cell-intrinsic mechanisms and the testicular microenvironment, and delineate the molecular mechanisms and stage-specific functions of the dynamic m⁶A regulatory network. We further discuss the current limitations in the field and propose feasible experimental strategies for future investigation. Collectively, this work aims to provide a comprehensive framework for understanding the epitranscriptomic regulation of spermatogenesis and to offer theoretical insights into the pathogenesis and clinical management of male infertility.

Spermatogenesis is a highly ordered and spatiotemporally regulated developmental process in the male reproductive system, during which spermatogonial stem cells (SSCs), supported by the seminiferous tubule microenvironment, sequentially undergo mitosis, meiosis, and spermiogenesis to ultimately generate structurally intact spermatozoa. This complex process is accompanied by extensive transcriptional reprogramming, chromatin remodeling, and finely tuned post-transcriptional regulation. Precise control of RNA fate is therefore essential for maintaining the continuity and fidelity of spermatogenesis, and its disruption represents a major molecular basis of male infertility. N⁶-methyladenosine (m⁶A), the most abundant internal RNA modification in eukaryotes, has emerged as a critical regulator of post-transcriptional gene expression. m⁶A methyltransferases (“writers”) catalyze the addition of a methyl group to the N⁶ position of adenosine, m⁶A demethylases (“erasers”) remove the modification, and m⁶A-binding proteins (“readers”) recognize m⁶A-modified transcripts. Through the coordinated actions of these factors, m⁶A regulates transcript fate at multiple levels, including RNA splicing, nuclear export, stability, translation, and decay. Emerging evidence indicates that m⁶A-mediated regulation is essential across multiple stages of spermatogenesis, including SSC self-renewal and differentiation, meiotic progression, maintenance of chromosomal stability, and sperm morphogenesis. Beyond its intrinsic functions in germ cells, m⁶A also contributes to the regulation of the testicular microenvironment. In sertoli cells, m⁶A is involved in maintaining blood-testis barrier integrity, RNA processing, and paracrine signaling, thereby providing structural and metabolic support for germ cell development. In Leydig cells, m⁶A regulates steroidogenesis, particularly testosterone synthesis, and participates in cellular stress responses and metabolic homeostasis. Through these mechanisms, m⁶A indirectly influences spermatogenesis by modulating the functional state of testicular somatic cells, highlighting an integrated regulatory mode that combines cell-intrinsic and microenvironment-mediated effects. Notably, distinct classes of m⁶A regulators exhibit pronounced stage-specific functions and coordinated division of labor, collectively forming a multilayered and dynamic regulatory network. Writers often display dosage- and temporal window-dependent effects; erasers contribute to stage-specific demethylation and functional compensation; while readers function through a “switch-buffer” dual-layer architecture, and RNA-binding proteins (RBPs) participate in substrate selection and post-transcriptional regulation. Importantly, emerging evidence suggests that some m⁶A-related proteins can function through noncanonical mechanisms independent of m⁶A recognition, such as intrinsic RNA-binding activity, helicase function, or ribonucleoprotein complex assembly, thereby expanding the functional landscape of the m⁶A regulatory system. Dysregulation of m⁶A machinery can lead to multiple spermatogenic defects, including impaired SSC self-renewal, meiotic arrest, abnormal chromatin remodeling, and defective sperm formation, ultimately resulting in male infertility. Despite substantial advances, several critical questions remain unresolved, including the distinction between m⁶A-dependent and -independent mechanisms, the spatiotemporal dynamics of m⁶A modifications at single-cell resolution, and the coordination and antagonism among different regulatory factors. In this review, we systematically summarize the dual regulation of spermatogenesis by germ cell-intrinsic mechanisms and the testicular microenvironment, and delineate the molecular mechanisms and stage-specific functions of the dynamic m⁶A regulatory network. We further discuss the current limitations in the field and propose feasible experimental strategies for future investigation. Collectively, this work aims to provide a comprehensive framework for understanding the epitranscriptomic regulation of spermatogenesis and to offer theoretical insights into the pathogenesis and clinical management of male infertility.

BACKGROUND:Preliminary research by our group suggests that targeting fibroblast growth factor receptor 1(FGFR1)may be an effective strategy for treating RA. OBJECTIVE:To investigate the effects of an FGFR1 inhibitor(PD173074)on bone destruction in rats with collagen-induced arthritis. METHODS:Twenty-five female Sprague-Dawley rats were randomly divided into five groups:normal control group,model group,methotrexate group,low-dose PD173074 group,and high-dose PD173074 group.Except for the normal control group,rat models of type Ⅱ collagen-induced arthritis were made in each group.After successful modeling,rats were injected intraperitoneally with sterile PBS in the normal and model groups,1.04 mg/kg methotrexate in the methotrexate group,and 5 and 20 mg/kg in the low-dose group and high-dose PD173074 groups,once a week.After 4 weeks of drug administration,clinical symptoms and joint swelling in rats were observed.Micro-CT was used for three-dimensional reconstruction and analysis of the ankle joints.Pathological changes in the ankle joints were observed.Periarticular angiogenesis and the expression of receptor activator of nuclear factor-Κb ligand were detected.The expression levels of p-FGFR1,vascular endothelial growth factor A,and tartrate-resistant acid phosphatase in the synovial membrane were measured.Pathological changes in the liver,spleen,and kidney were observed and liver,spleen,and kidney indices were calculated. RESULTS AND CONCLUSION:PD173074 could alleviate clinical symptoms and joint swelling,delay bone loss,improve bone structure,reduce synovial invasion and cartilage bone erosion,reduce the number of periarticular osteoclasts,inhibit angiogenesis in synovial tissues,reduce the expression of receptor activator of nuclear factor-Κb ligand,and inhibit the expression of FGFR1 phosphorylated protein,tartrate-resistant acid phosphatase and vascular endothelial growth factor A.Pathologic observation of the liver,spleen and kidney in rats showed no obvious toxic side effects after PD173074 treatment.To conclude,the FGFR1 inhibitor can delay the progression of joint inflammation and bone destruction and inhibit angiogenesis in the rat model of type Ⅱ collagen-induced arthritis.The therapeutic effect of PD173074 has been preliminarily validated in the type Ⅱ collagen-induced arthritis model and may act by inhibiting FGFR1 phosphorylation,which provides a direction for the search of new therapeutic targets for rheumatoid arthritis.

Severe open tibiofibular fractures account for approximately 28.1% of all open fractures. Among them, Gustilo-Anderson type IIIB/C fractures present significant clinical challenges due to associated bone and soft tissue defects, high infection rates, and risk of amputation. Inadequate preoperative assessment may lead to suboptimal emergency surgical planning or intraoperative complications. Historically, external fixation was often preferred, but this approach has been associated with limitations such as restricted joint mobility, delayed bone union, joint stiffness, and disuse osteoporosis, resulting in poor functional recovery. With advancements of debridement techniques, standardization of antibiotic use, and popularization of early soft tissue coverage, early internal fixation has gained broader acceptance. Nevertheless, controversies persist regarding the choice of fixation method, timing of definitive fixation, use of reamed versus unreamed intramedullary nailing, and necessity of fibular fixation. To standardize the diagnosis and early management of severe open tibiofibular fractures, reduce complication rates, and improve functional recovery, the Society of Microsurgery of the Chinese Medical Association organized a panel of domestic experts to develop the Evidence-based guideline for the diagnosis and early fixation of severe open tibiofibular fractures ( version 2025), using evidence-based methodology. The guidelines provided 12 recommendations covering diagnostic and early fixation strategies of severe open tibiofibular fractures, aiming to provide clinicians with scientifically grounded and standardized guidance.

Objective:To compare the clinical and laboratory characteristics and survival between Chinese and Western patients with myelodysplastic neoplasms (MDS) .Methods:Clinical and laboratory data were collected from 1,464 primary adult patients diagnosed with MDS at the Institute of Hematology & Blood Diseases Hospital from August 2016 to June 2024. Collected data were retrospectively analyzed and compared with 2,191 patients from the International Working Group for the Prognosis of Myelodysplastic Syndromes (IWG-PM) .Results:Chinese patients were significantly younger (median age: 56 years vs. 72 years, P<0.001) and experienced more severe hematopenia ( P<0.001) compared with patients from the IWG-PM. Further, Chinese patients exhibited a higher percentage of isolated del (20q), +8, and complex karyotypes as well as a lower percentage of normal karyotypes, del (5q), and -Y ( P<0.001). Higher U2AF1, NRAS, and NPM1 mutation rates and lower ASXL1, SF3B1, and RUNX1 mutation rates were observed in Chinese patients than in participants from the IWG-PM ( P<0.05). No significant difference in overall survival (OS) was found between the two groups (median OS: 48 [95% CI: 40 - 56]months, vs. 45[95% CI: 40 - 49] months; P=0.449). Among participants aged ≤45 years, Chinese patients demonstrated more trisomy 8 ( P=0.070) and U2AF1 mutation ( P<0.001) and higher 4-year OS rate compared with those from the IWG-PM (75.5% vs. 62.1%, P=0.001). Among participants aged ≥70 years, Chinese patients exhibited more complex karyotypes but fewer del (5q) as well as more NPM1 but less SF3B1 and TET2 compared with those from the IWG-PM ( P<0.05). Chinese patients demonstrated shorter survival (median OS: 20 [95% CI: 13 - 27] months vs. 37 [95% CI: 32 - 42] months, P<0.001) . Conclusion:Chinese and Western MDS patients differ in age of onset, clinical features, and cytogenetic or molecular genetic abnormalities, with significant differences persisting in age-matched groups. Although the OS is similar, disparities exist in survival for younger and older patients between the two populations.

Objective:To explore the clinical features and molecular characteristics of myeloproliferative neoplasms (MPNs) patients with NFE2 gene mutations.Methods:Gene targeted sequencing was used to detect NFE2 gene mutation in 723 patients diagnosed with MPNs who were admitted to Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College between April 2021 and June 2023. The association between NFE2 gene mutations and clinical features and molecular characteristics of MPNs patients were retrospectively analyzed.Results:Among 723 patients with MPNs, NFE2 gene mutations were found in 41 cases (5.7%) . NFE2 gene mutations were predominantly frameshift mutations (44.4%) , followed by nonsense mutations (33.3%) . The median number of mutations in patients with NFE2 gene mutations (4 [2,5]) was higher compared to the group without NFE2 gene mutations (2, [1,3]) ( P<0.001) . NFE2 gene mutations frequently co-occurred with mutations in MPL, ATM, PPM1D, and TET1. NFE2 gene mutations were mostly sub-clonal events, with 80.5% occurring after MPNs driver mutations (JAK2, CALR, or MPL) . NFE2 mutations were correlated with older age [median age: 60 (54, 67) years vs 54 (41, 63) years, P=0.001]. Patients with NFE2 gene mutations had a higher incidence of pre-diagnosis thrombosis (39.0% vs 22.0%, P=0.012) and pre-diagnosis arterial thrombosis (36.6% vs 20.4%, P=0.014) . Using a logistic regression analysis model adjusting for age and comorbidities (including chronic infections, malignancies, and autoimmune diseases) , NFE2 gene mutation was identified as an independent determinant of elevated tumor necrosis factor-alpha (TNF-α) ( OR=2.747, 95% CI: 1.143-6.605, P=0.024) , interferon-gamma (IFN-γ) ( OR=2.689, 95% CI: 1.191-6.076, P=0.017) , IL-10 ( OR=3.219, 95% CI: 1.343-7.717, P=0.009) , IL-12P70 ( OR=3.397, 95% CI:1.003-11.508, P=0.049) , IL-17 ( OR=2.284, 95% CI: 1.017-5.127, P=0.045) . In polycythaemia vera (PV) patients with the NFE2 gene mutation, the proportion of those classified as high-risk is notably higher in both the IWG-PV and mutation-enhanced international prognostic systems for PV (MIPSS-PV) (66.7% vs 25.3% for IWG-PV, P=0.033; 22.2% vs 2.0% for MIPSS-PV, P=0.013) . Similarly, for essential thrombocythaemia (ET) patients, the proportion in the high-risk group of the mutation-enhanced international prognostic systems for ET (MIPSS-ET) is significantly higher (15.4% vs 6.1%, P=0.021) . No statistically significant differences were observed in overall survival or cumulative incidence of thrombosis between NFE2-mutated (38 cases) and non-mutated MPNs patients (671 cases, P>0.05) . Conclusion:NFE2 gene mutations in MPNs were predominantly frameshift mutations. NFE2 gene mutations were correlated with older age, elevated levels of several inflammatory factors (including TNF-α、IFN-γ、IL-10、IL-12P70、IL-17) , and they mostly occurred in late-stage of MPNs.

Objective:To investigate the clinical, laboratory, and prognostic features of myelodysplastic neoplasm (MDS) patients harboring acute myeloid leukemia (AML) -like mutations.Methods:We retrospectively analyzed clinical, molecular, and outcome data from 1 464 adults with primary MDS diagnosed at the Institute of Hematology and Blood Diseases Hospital from August 2016 to June 2024.Results:AML-like mutations were detected in 64 patients (4.4% ). Compared with patients without AML-like mutations, those with AML-like mutations were younger [median 50 ( IQR 39–60) vs 56 (45, 65) years; P=0.001], more often female (51.6% vs 35.4% ; P=0.009), had higher bone marrow blast percentage [6.5% (3.0%, 10.5% ) vs 2.5% (1.0%, 7.0% ) ; P<0.001], a higher rate of normal karyotype (75.0% vs 48.1% ; P<0.001), and lower hemoglobin levels [73 (67, 82) g/L vs 80 (66, 98) g/L; P=0.006]. The AML-like group had a higher number of gene mutations than the non-AML-like group [3 ( IQR 2–4) vs 2 (1, 3) ; P<0.001). It was enriched for mutations in NPM1, DNMT3A, WT1, PTPN11, NRAS, BCOR, FLT3, CEBPA, and MYC (all P<0.05) and had lower rates of U2AF1, ASXL1, and TP53 mutations (all P<0.05). Overall survival (OS) did not differ between groups ( P=0.730) ; however, the AML-like group had significantly shorter leukemia-free survival (LFS) [19 months (95% CI: 13–25) vs 46 months (95% CI: 38–54) ; P=0.012] and a higher 2-year cumulative incidence of AML transformation [ (41.7±9.1) % vs (10.4±1.1) % ; P<0.001]. Within the AML-like group, OS, LFS, and cumulative incidence of AML transformation did not differ between patients with low blasts and those with excess blasts (IB). Multivariable Cox regression identified age ≥60 years and PTPN11 mutations as independent adverse prognostic factors for OS, while DNMT3A, PTPN11, and FLT3 mutations independently predicted leukemic transformation. Conclusions:MDS patients harboring AML-like mutations exhibit distinct clinical and molecular features and a higher risk of progression to AML.

Objective To explore the role of miR-429 in synovial mesenchymal stem cell-derived exosomes(SMSC-Exos)in repairing cartilage damage in temporomandibular joint osteoarthritis(TMJ OA)by extracting SMSC-Exos from human synovial tissue and screening differentially expressed microRNA(miRNA)through transcriptome sequencing.Methods Human synovial tissues were obtained from 6 patients who underwent surgery at the First Medical Center of the Chinese PLA General Hospital from June to December 2023,including 3 patients with osteoarthritis(OA group)and 3 control patients(control group),all of whom were male.SMSC-Exos were extracted from the synovial tissues for miRNA sequencing and differential expression analysis.Further,Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analyses were performed on the target genes of differentially expressed miRNA to identify key functional miRNA and construct miRNA-target gene regulatory networks and protein-protein interaction(PPI)networks of target genes.An in vitro model of rabbit condylar cartilage cell inflammatory microenvironment induced by interleukin-1β(IL-1β)was established,with the control group cultured in DMEM/F12 basic medium and the inflammation-induced group cultured in DMEM/F12 basic medium containing 10 ng/ml IL-1β.RT-qPCR was used to detect the effects of overexpressed target miRNA on the mRNA expression levels of cartilage phenotype factors such as type Ⅱ collagen α1 chain(Col2a1),aggrecan(Acan),as well as inflammatory factors including a disintegrin and metalloproteinase with thrombospondin motifs 5(Adamts5)and cyclooxygenase-2(Cox-2).Results(1)SMSC-Exos were successfully isolated,cultured,and identified.(2)miRNA sequencing of SMSC-Exos from OA and control groups revealed 16 differentially expressed miRNAs(|log2FC|>2,P<0.05).Compared with control group,7 miRNAs were up-regulated and 9 were down-regulated in OA group.GO and KEGG analysis indicated that the target genes of miR-429 were mainly involved in development process,anatomical structure development,system development,cell development and differentiation,and were enriched in inflammation-related pathways such as mitogen-activated protein kinase(MAPK)and phosphatidylinositol 3-kinase-protein kinase B(PI3K-Akt).(3)Functional validation of miR-429 in the rabbit condylar cartilage cell inflammatory model showed that overexpression of miR-429 increased the mRNA expression levels of Col2a1 and Acan(P<0.05)and decreased the mRNA expression levels of Adamts5 and Cox-2(P<0.05)in the inflammation-induced group.Conclusions miRNA sequencing of SMSC-Exos isolated and identified from human synovial tissues reveals a specific miRNA expression profile in OA patients,with miR-429 significantly down-regulated.Functional validation demonstrates that overexpression of miR-429 has reparative and anti-inflammatory effects on condylar cartilage cells in an inflammatory microenvironment.