The etiology of acute Achilles tendon rupture (ATR) remains unclear. This study conducted a comprehensive case-control study of the proteome profile to gain insights into the potential pathogenesis of Show more
The etiology of acute Achilles tendon rupture (ATR) remains unclear. This study conducted a comprehensive case-control study of the proteome profile to gain insights into the potential pathogenesis of acute ATR and identify novel biomarkers. Serum (iTRAQ) and urine (label-free proteomics) from 15 acute ATR patients and 15 healthy controls were analyzed. Significant differential expression was defined as ≥1.2-fold (serum) or ≥2-fold (urine) change with p < 0.05. Bioinformatics analyses (GO, KEGG, PPI) were performed. 44 serum and 198 urine proteins were differentially expressed. Enriched pathways included immune response, metabolism, immune response, and redox regulation. protein-protein interaction analysis of the differentially expressed proteins (P < 0.05) highlighted abnormalities in major protein-protein interaction hubs, specifically pyruvate kinase (PKM), peroxiredoxin-1 (PRDX1), phosphoglycerate kinase 1 (PKG1), profilin-1, and apolipoprotein A-IV, observed in the serum and urine samples of acute ATR patients. Metabolic dysregulation may affect tendon structure/strength; redox imbalance could promote degeneration. Immune-related proteins may reflect injury responses. Glycolytic enzymes (PKM, PGK1) suggest disrupted energy metabolism. Proteomic abnormalities in metabolism, immune, and redox pathways, along with key proteins (PKM, PRDX1, PGK1), may contribute to ATR pathogenesis, offering potential biomarkers warranting further validation. Show less
Spontaneous Achilles tendon rupture (SATR) predominantly affects middle-aged and elderly individuals with chronic injuries. However, the exact cause and mechanism of SATR remain elusive, and potential Show more
Spontaneous Achilles tendon rupture (SATR) predominantly affects middle-aged and elderly individuals with chronic injuries. However, the exact cause and mechanism of SATR remain elusive, and potential therapeutic intervention or prevention is still insufficient. The present study aimed to uncover the key pathological molecules by using iTRAQ proteomics. The results identified 2432 candidate proteins in SATR patients using iTRAQ proteomic analysis. A total of 307 differentially expressed proteins (DEPs) were identified and linked to 211 KEGG signaling pathways including Coronavirus disease (COVID-19), focal adhesion, and ribosomes. GO enrichment analysis highlighted significant enrichment in processes such as biological adhesion, ossification, lipid (APOA4) processes, and extracellular matrix (ECM) organization (collagen). PPI network analysis identified hub genes such as serum albumin (ALB), fibronectin (FN1), and actin cytoplasmic 1. The WB analysis confirmed that FN1 and the receptor for activated C kinase (RACK1) were downregulated in the SATR tendon. Immunohistochemical staining revealed that collagen I and III were suppressed, while collagen II and APOA4 expression were higher in the SATR pathological tissue ( Show less
Due to its limited blood supply and irregular mechanical loading, the Achilles tendon is the most frequently ruptured tendon. Despite the rising incidence of acute Achilles tendon rupture (AATR), the Show more
Due to its limited blood supply and irregular mechanical loading, the Achilles tendon is the most frequently ruptured tendon. Despite the rising incidence of acute Achilles tendon rupture (AATR), the optimal treatment remains controversial. Missed diagnoses and delayed treatments lead to poor outcomes and limited treatment options. This study aimed to identify potential biomarkers for diagnosing and developing therapies for AATR. We employed the coupled isobaric tag for relative and absolute quantitation-liquid chromatography-electrospray ionization-tandem mass spectrometry approach to investigate protein expression in tissues from AATR patients. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were conducted to identify differentially expressed proteins (DEPs) between AATR patients and healthy individuals. A protein-protein interaction (PPI) network of DEPs was constructed using the Search Tool for the Retrieval of Interacting Genes. The screened hub genes were selectively verified by immunohistochemical staining. We identified 410 DEPs between AATR patients and controls. The DEPs were significantly enriched in GO terms such as the extracellular region, extracellular region part, and defense response, as well as KEGG pathways, including complement and coagulation cascades, focal adhesion, and regulation of actin cytoskeleton. The main hub nodes in the PPI network comprised fibronectin 1 (FN1), major histocompatibility complex, class I, B (HLA-B), filamin A (FLNA), heat shock 27-kDa protein 1 (HSPB1), heat shock protein family A member 5 (HSPA5), apolipoprotein A4 (APOA4), and myosin IC (MYO1C). Although APOA4 and collagens I, II, and III were detectable in healthy tendons, immunohistochemical staining confirmed higher expression of these proteins in the acutely ruptured Achilles tendon. Our findings lay a foundation for further molecular studies of AATR. Inflammation and age-related degeneration may contribute to the pathogenesis of AATR. Moreover, the identified DEPs could be potential biomarkers for AATR diagnosis and treatment. Show less