UNASSIGNED: We aimed to investigate the transcriptomic alterations that occur in the subacromial bursa (SAB) following degenerative or traumatic shoulder diseases.
UNASSIGNED: RNA sequencing was employed to evaluate the transcriptomic alterations of the SAB in individuals afflicted with degenerative rotator cuff tear (RCT), traumatic RCT and proximal humerus fracture (PHF). To gain insights into the biological significance of differentially expressed genes (DEGs), we conducted an enrichment analysis utilizing Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. We further utilized single-cell RNA sequencing datasets of SAB from a recently published study to explore the associated cellular dynamics and alterations.
UNASSIGNED: We detected 1,790 up-regulated and 1,964 down-regulated DEGs between degenerative RCT and PHF, 2,085 up-regulated and 1,919 down-regulated DEGs between degenerative RCT and traumatic RCT, and 20 up-regulated and 12 down-regulated DEGs between traumatic RCT and PHF. Given the similar expression pattern between traumatic RCT and PHF, they were integrated as the traumatic group. In comparison with the traumatic group, 1,983 up-regulated and 2,205 down-regulated DEGs were detected in degenerative SAB. Enrichment analysis of up-regulated DEGs uncovered an elevated inflammatory and immunologic responses in degenerative SAB. Single-cell transcriptomic analysis revealed macrophage represented the immune cell with the most DEGs between the degenerative and traumatic RCT.
UNASSIGNED: Our results revealed that the SAB in degenerative RCT exhibited a different transcriptional signature compared to that in traumatic RCT, and enrichment analysis showed immunologic and inflammatory activations. Macrophages may play a fundamental role in this process.

UNASSIGNED: Although adhesive capsulitis (AC) is a common condition, the pathological mechanisms remain understudied. The purpose of our research was to evaluate variations in gene expression across the entire genome in the subacromial bursa tissue of individuals with rotator cuff tears (RCT), with or without AC, and to explore the factors that may influence the occurrence and progression of AC.
UNASSIGNED: Transcription profiles of subacromial bursa samples from 12 RCT patients, of whom 6 had also AC, were evaluated. Data were generated using RNA-seq. DESeq2 was utilized to identify the differentially expressed genes (DEGs) in both groups. In order to conduct a more in-depth examination of the DEGs, we performed Gene Ontology (GO) functional enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. A network of interactions between proteins was built, and the central genes were determined using Cytoscape. The hub genes were confirmed through qRT-PCR and immunohistochemistry.
UNASSIGNED: 324 of the 16,251 detected genes were identified as DEGs. Analysis of GO functional enrichment showed that the DEGs were enriched in domains of biological process, molecule function and cellular component. Analysis of KEGG pathways revealed enrichment of DEGs in pathways like IL-17 signaling and ECM-receptor interaction. We verified that the association between AC and the increase in expression of the PPI network hub genes.
UNASSIGNED: This study investigated the transcriptome differences of subacromial bursa in RCT patients with or without AC. Using bioinformatics technology, we identified the DEGs and screened out the hub genes. The research enhanced the data on gene expression profiles of DEGs in the subacromial bursa tissue of patients with RCT, offering fresh perspectives on the regulation of gene transcription.

BACKGROUND: The role of subacromial bursa in rotator cuff surgery is unknown. This study aimed to assess the subacromial bursa\'s role in the healing of supraspinatus tendon injury in a rat model.
METHODS: Twenty-three male Sprague-Dawley rats (9 weeks old; weight, approximately 296 g) were used in this study. Three rats used as biomechanical study controls were killed at 12 weeks of age. A supraspinatus tendon defect was made bilaterally in 20 rats, whereas an additional subacromial bursa sectioning was performed on the left side. Six rats were killed for biomechanical testing and 4 were killed for histologic observation at 3 and 9 weeks, respectively.
RESULTS: The regenerated tendon in the bursal preservation group showed significantly superior biomechanical properties in maximum load to failure at 3 and 9 weeks and stiffness at 9 weeks after surgery compared with the bursal removal group. The modified Bonar scale scores showed better regenerated supraspinatus tendons in the bursal preservation group.
CONCLUSIONS: The present study found that the subacromial bursa plays an important role in rotator cuff regeneration in this rat supraspinatus injury model. Extensive bursectomy of the subacromial bursa may not be recommended in rotator cuff repair surgery, though future in vivo human studies are needed to confirm these observations.