The Signification Of The Expression Of The PI3K/Akt Pathway With Related Signaling Molecule In Human Knee Osteoarthritis

Objective To observae the expression of PI3K,Akt and Bad in knee osteoarthritis(OA),investigating the role of PI3K/Akt signaling pathway in the pathogenesis of OA,in order to provide some evidence for explaining the pathogenesy of osteoarthritis.Methods A total of 31 samples of OA human cartilage which were collected from knee arthroplasty.A total of 10 samples of normal human cartilage which were collected from patients who were amputated because of unintentional injuries or have discoid meniscus.The normal HE staining were used to obserbe their histological pattems;TUNEL metheod were used to detect the apoptosis of chondrocytes;S-P immunohistochemistry staining were used to detect the expression of PI3K,Akt and Bad protein in cartilage.Image-Pro Plus 6.0 was used to make quantitative analysis. Two-sample t-test was used for statics.Laser scanning confocal microscope was used to observed the change of the location of akt in the cartilage cells.Results①The contrast of normal human cartilage and OA human cartilage in histological:The surface of normal articular are smooth and flat,the intercellular layer chondrocyte were uniformly distributed,no cluster cartilage cells and the full tide line.The thickness of OA cartilage become thin,the superficial layer become cracked;the intercellular layer chondrocyte and deep layer chondrocyte are disorder,maldistribution and the fracture line.②The distribution of PI3K,Akt and Bad protein in normal human cartilage and OA human cartilage:PI3K and Akt are mainly distributed in the superficial layer and intercellular layer in normal human cartilage,and mainly distributed in intercellular layer in OA human cartilage.They are a small number of or even not distributed in the superficial layer in OA human cartilage.But the distribution of Bad was no significant difference between normal human cartilage and OA human cartilage,mainly distributed in intercellular layer.③the expression of PI3K,Akt and Bad protein in normal human cartilage and OA human cartilage:the expression value of PI3K in the intercellular layer is t=6.189, P＜0.05;the expression value of PI3K in the deep layer is t=3.225,P≤0.05;the expression value of Akt in the intercellular layer is t=9.056,P≤0.05;the expression value of Akt in the deep layer is t=2.768,P＜0.05.It show that the expression of PI3K, Akt in the knee OA cartilage tissue was significantly lower than that in normal human articular cartilage tissue.It has significant differences in the intercellular and deep cartilage tissue,and especially for Akt.the expression value of Bad in the intercellular layer is t=0.567,P＞0.05;the expression value of Bad in the deep layer is t=-0.35,, P＞0.05.It show that the expression of Bad are both in normal human articular cartilage tissue and in knee OA cartilage tissue,and it has no significant differences between them.④The distribution of Akt is mainly in cytoplasma,and its expression is partly reduced in chondrocytes of OA.Conclusion Compared with the normal human cartilage,the superficial layer in OA human cartilage was significantly reduced or even absence.The expression of PI3K and Akt protein in OA human cartilage was significantly lower.The weakening of PI3K/Akt pathway in chondrocyte is one the main biological factors for the destruction of articular cartilage.The content of Bad was no significant difference between normal human cartilage and OA human cartilage infer that Bad is not participation in life activities of OA human cartilage,The regulation of PI3K/Akt pathway may have another substrate.