Abstract:

BACKGROUND: Phosphatidylinositol 3-kinase (PI3K)/protein kinase B (PKB/Akt) signal pathway has been shown to promote cell proliferation and inhibit apoptosis. Application of PI3K/Akt signal pathway in osteoarthritis has aroused increasing attention, but its expression in human knee osteoarthritis cartilage tissue remains unclear.
OBJECTIVE: To investigate the changes of Akt, Bad pathway in knee osteoarthritis.
METHODS: The 31 samples of osteoarthritis human cartilage (experimental group) and 10 samples of normal human cartilage (control group) were selected. The normal histological technique and immunohistochemistry staining are used to detect the expression of Akt and Bad protein. 
RESULTS AND CONCLUSION: ①The osteoarthritis cartilage became thinner, and the superficial layer becomes cracked; the chondrocytes in the intercellular and deep layer were disordered in the distribution. ②The expression of Akt protein in middle and deep layers of osteoarthritis human cartilage was significantly lower than normal human cartilage (P < 0.01), but the expression of Bad was similar between normal human cartilage and osteoarthritis human cartilage (P > 0.01). It is suggested that the PI3K/Akt pathway is closely related to the occurrence and development of the knee osteoarthritis. PI3K/Akt pathway changes may a major factor inducing articular cartilage damage. Bad dose not participate chondrocyte activities of osteoarthritis, but there is other substrate exists in PI3K/Akt pathway.