Correlation between serum matrix metalloprotein-9, tumor necrosis factor alpha and OPG/RANK/RANKL system in stable chronic obstructive pulmonary disease patients with osteoporosis

Abstract

Objective To explore the correlation between serum matrix metalloprotein-9 (MMP-9), tumor necrosis factor alpha (TNF-α) and osteoprotegerin/receptor activator of nuclear factor kappa B/receptor activator of NF-κB ligand (OPG/RANK/RANKL) in male stable chronic obstructive pulmonary disease(COPD) patients with osteoporosis. Methods One hundred and twelve male COPD patients were enrolled in the study.According to the results of bone mineral density test, the patients were divided into three groups: normal bone mass group, low bone mass group and osteoporosis group.The correlation between bone mineral density and serum MMP-9, TNF-α and OPG/RANK/RANKL was analyzed. Results ①There were differences in body mass index (BMI), chronic obstructive pulmonary disease assessment test score, lumbar bone mineral density and femoral neck bone mineral density among the three groups (P<0.01). There was a significant positive correlation between lumbar bone mineral density and femoral neck bone mineral density and BMI.Lumbar spine bone mineral density and femoral neck density were significantly negatively correlated with CAT score.②There were significant differences in serum MMP-9, TNF-α, OPG, RANKL and RANKL/OPG levels among the three groups (P<0.05). ③The lumbar bone density, femoral neck bone density and FEV1%pred were significantly negatively correlated with the level of MMP-9 RANKL and RANKL/OPG.④The lumbar bone density was set as the dependent variable, and the related cytokines were independent variables, and the regression equation was obtained, Y=1.658-0.001X1-0.004X2 (Y: bone mineral density, X1: RANKL, X2: MMP-9). ⑤The bone density of the neck of the femur was set as the dependent variable, the level of the related cytokines was the independent variable, and the equation was obtained, Y=1.393-0.006X1-0.130X2 (Y: bone mineral density, X1: MMP-9, X2: RANK). Conclusions MMP-9 and RANKL play a key role in the occurrence of osteoporosis in male stable COPD patients.MMP-9, TNF-α and OPG/RANK/RANKL systems may play a positive synergistic role in the occurrence and development of lung injury and bone mineral density in patients. Key words: Chronic obstructive pulmonary disease; Osteoporosis; Bone mineral density