Gene expression and histological studies of articular chondrocytes in cam-type femoroacetabular impingement demonstrates chronic and sustained inflammation and age related abnormal extracellular matrix

IntroductionFemoroacetabular impingement (FAI) is a frequent cause of hip pain associated with the degeneration cartilage in joint. However, molecular events linking bone and deformation joint are unclear.ObjectiveUsing gene expression histological analyses cam-type FAI tissues to discover abnormal biological changes chondrocytes that contribute pathophysiology FAI.MethodsFull-thickness specimens obtained from donors who underwent arthroscopy address symptomatic were analyzed. Quantitative real-time polymerase chain reaction (RT-PCR) was performed assess expressions markers for inflammation, extracellular matrix (ECM) synthesis, cellular senescence. Histological prepared safranin O/fast green staining as well immunohistochemistry evaluation.ResultsCompared normal cartilage, demonstrated decreased ACAN, COL2, Sox9. Additionally, these showed increased MMP13, ADAMTS4, IL-1β, p21, Bcl-2, FasL. revealed two distinct phenotypes: O positive (SO+) negative (SO-) different stages related patient age. Immunohistochemical studies MMP3, PCNA differences between SO+ SO- groups.ConclusionsGene indicated chronic sustained inflammation age degradation cell senescence major characteristics tissue.