RESUMO
BACKGROUND:Intervertebral disc degeneration is the basis of spinal degenerative diseases;however,there is no effective treatment. OBJECTIVE:To investigate whether sinomenine can inhibit interleukin-1β-induced apoptosis in nucleus pulposus cells and its molecular mechanism. METHODS:Rat nucleus pulposus cells were cultured in vitro by trypsin combined with type II collagenase digestion,and the cell growth curve was plotted.An appropriate sinomenine concentration was determined using the cell counting kit-8 kit.Nucleus pulposus cells were divided into control group,sinomenine group,interleukin-1β group,sinomenine+interleukin-1β group,zinc protoporphyrin group,zinc protoporphyrin+sinomenine group,zinc protoporphyrin+interleukin-1β group,and sinomenine+zinc protoporphyrin+interleukin-1β group.Proliferative activity,reactive oxygen species content,apoptosis rate,and heme oxygenase-1 expression in nucleus pulposus cells were detected. RESULTS AND CONCLUSION:The rat nucleus pulposus cells cultured in vitro were polygonal,triangular,and short wedge-shaped,and the cell growth showed an"S"curve.The cells grew slowly in the first 3 days of culture,rapidly in 4-6 days,and slowly again in 7-8 days.The cells then entered the"platform stage"where the number of cells no longer increased.The proliferative activity of myeloid cells showed no significant changes when the concentration of sinomenine was≤80 μmol/L(P>0.05).Interleukin-1β significantly reduced the proliferative activity of nucleus pulposus cells,increased the content of reactive oxygen species and led to apoptosis(P<0.01).Sinomenine intervention not only promoted heme oxygenase-1 expression(P<0.05)but also inhibited interleukin-1β-induced decrease in proliferative activity and increase in reactive oxygen species content and apoptosis rate in nucleus pulposus cells(P<0.05).These effects could be reversed by zinc protoporphyrin(P<0.01).