原代软骨细胞专用培养基

Background Intervertebral disc (IVD) degeneration (IDD) represents a predominant origin of low back pain and disability, yet current therapeutic interventions remain suboptimal. Emerging evidence highlights autophagy activation as a therapeutic strategy against IDD. This study investigates the mechanistic interplay between N6-methyladenosine (m6A) modifications and autophagy dysregulation in IDD pathogenesis. Methods Bioinformatics analysis identified ring finger protein 41 ( RNF41 ) as a key autophagy-IDD intersection gene. Functional validation utilized tert-butyl hydroperoxide (TBHP)-treated human nucleus pulposus (NP) cells to assess RNF41’s effects on senescence (CDKN2A), autophagy (LC3-II/p62), apoptosis (TUNEL), inflammation (IL-18/IL-1β), and extracellular matrix (ECM) homeostasis (aggrecan/MMP). Key m6A regulators modulating autophagy were screened via correlation analysis. In vivo validation employed adeno-associated virus (AAV)-mediated methyltransferase-like 3 (METTL3)/RNF41 delivery in puncture-induced IDD rat models. Results RNF41 expression was downregulated in human IVD tissues. Overexpression of RNF41 mitigated TBHP-induced senescence, apoptosis, activated AMPK/mTOR-mediated autophagy, suppressed inflammation, and restored ECM balance. The autophagy inhibitor chloroquine (CQ) abolished the protective effects of RNF41 overexpression on degenerative NP cells. Mechanistically, METTL3/YTHDC1 co-regulation in degenerative NP cells mediated m6A hypermethylation of RNF41 mRNA, shortening its half-life via YTHDC1-dependent decay. Intradiscal METTL3-silencing AAV attenuated puncture-induced disc loss and histopathological degeneration, whereas RNF41-silencing AVV exacerbated ECM disruption and annular disorganization. Conclusion METTL3/YTHDC1-mediated m6A modification drives IDD progression by silencing RNF41 , thereby impairing autophagy and ECM integrity. Targeting this axis offers a clinically actionable strategy to delay disc degeneration, particularly in patients with early-stage IDD. This evidence establishes RNF41’s role as a theragnostic biomarker and therapeutic targe, enabling precision-guided interventional approaches.

Type II collagen (CII), the major structural protein in the cartilage extracellular matrix, is a promising biomaterial for scaffold design in cartilage tissue engineering. In this study, high-purity CII was successfully extracted from bovine cartilage, an abundant by-product of cattle slaughter, and its amino acid composition, triple-helical conformation, and thermal stability were verified. CII was subsequently combined with silk fibroin (SF) and chitosan (CS) to fabricate three-dimensional (3D) porous scaffolds via freeze-drying. The pore structure, porosity, swelling behavior, mechanical properties and in vitro degradation characteristics were systematically evaluated. Scaffolds with favorable structural integrity, mechanical performance, and degradation rates were further evaluated biologically using human primary chondrocytes. All CII-based composite scaffolds supported chondrocyte growth and promoted early extracellular matrix deposition. Notably, the scaffold with a CII:SF:CS ratio of 7:3:1 showed the highest GAG/DNA content, accompanied by upregulated gene expression related to the cartilage phenotype (COL2A1, ACAN, and SOX9) and reduced expression of the dedifferentiation marker COL1A1, indicating improved phenotype maintenance. Overall, within the tested range, CII70 (CII:SF:CS = 7:3:1) represents a practical compromise between scaffold stability and in vitro chondrocyte-related outcomes, providing a basis for selecting CII/SF/CS formulations for cartilage tissue engineering.

Platelet-rich plasma (PRP) has been shown to be beneficial to Frozen shoulder (FS), but the mechanism of PRP's intervention in FS is still incomplete. Ferroptosis and inflammation are important pathological factors of cartilage injury, but their role in FS has not been explored. In vivo , we found that PRP treatment significantly enhanced the joint range of motion and mitigated joint histopathological damage in FS rats. Notably, levels of iron ions, the ferroptosis marker prostaglandin-endoperoxide synthase 2 (PTGS2), reactive oxygen species (ROS), malondialdehyde (MDA), and pro-inflammatory cytokines (IL-6, IL-1β, TNF-α) in the cartilage tissue of PRP-treated rats were significantly reduced. Conversely, levels of superoxide dismutase (SOD) and glutathione (GSH) were markedly increased. In vitro experiments revealed that PRP effectively countered the IL-1β-induced suppression of chondrocyte proliferation while also reducing levels of ferroptosis and inflammation. Furthermore, the CST1/GPX4 pathway was suppressed in the FS environment, while it has the potential to be activated by PRP. Importantly, silencing CST1 negated the therapeutic effects of PRP on IL-1β-treated chondrocytes and FS rats. In summary, we found that PRP alleviated the progression of FS by inhibiting ferroptosis and the inflammatory response by activating the CST1/GPX4 signaling pathway

The molecular mechanisms underlying growth hormone (GH) therapy in children with idiopathic short stature (ISS) remain incompletely understood. This study investigated how GH promotes bone growth in children with ISS, focusing on insulin-like growth factor-binding protein 2 (IGFBP2) and thrombospondin-1 (THBS1). Analysis of ISS patient plasma showed downregulated IGFBP2, predicted to interact strongly with THBS1. Experiments using human chondrocytes revealed that GH treatment stimulated cell proliferation, accelerated the cell cycle, and induced hypertrophic differentiation, marked by increased expression of proteins like COL10A1, RUNX2, OCN, OPN, and alkaline phosphatase activity. GH also elevated IGFBP2 and insulin-like growth factor-1 (IGF-1) while suppressing THBS1. Crucially, knocking down IGFBP2 blocked these GH effects, reducing proliferation, halting cell cycle progression, decreasing differentiation markers and IGF-1, while increasing THBS1. Conversely, overexpressing IGFBP2 mimicked GH's effects. Importantly, silencing IGFBP2 partially prevented GH-induced proliferation, differentiation, and IGF-1 secretion. This demonstrates that IGFBP2 acts as a key mediator of GH's action by inhibiting THBS1, which subsequently activates the IGF-1 pathway to drive chondrocyte proliferation and hypertrophic differentiation. The IGFBP2-THBS1 axis is thus a core mechanism for GH therapy in ISS, offering a novel therapeutic target for improving treatment.