Objective To explore the correlation of protein and mRNA levels of monocyte chemotactic protein-1 (MCP-1) and serum amyloid A protein (SAA) with cognitive function in chronic obstructive pulmonary disease (COPD) patients with or without hypoxemia, in order to identify the serum indexes of early cognitive impairment in patients with COPD, and investigate the effect of hypoxemia on cognitive impairment. Methods Sixty-two COPD patients admitted in the respiratory department of Affiliated Hospital of North China University of Science and Technology from January 2013 to January 2017 were included in the study. The COPD patients were divided into a hypoxemia group (25 cases) and a non-hypoxemia group (37 cases) according to blood gas analysis. Meanwhile 30 healthy subjects were recruited as control. ELISA was used to measure the concentration of serum MCP-1 and SAA in all subjects, and RT-PCR was used to detect the mRNA expression of MCP-1 and SAA in peripheral blood mononuclear cells. Montreal cognitive assessment scale (MoCA scale) was used to determine cognitive function. The expression levels of MCP-1 and SAA were compared between three groups, and the correlations with cognitive dysfunction were analyzed. Results The expression levels of serum MCP-1 and SAA had the same trend as those of MCP-1 mRNA and SAA mRNA in peripheral blood in the COPD patients. The protein and mRNA levels of MCP-1 and SAA were higher than those in the healthy control group (all P<0.05). The COPD hypoxemia group and the COPD non-hypoxemia group were lower than the control group in MoCA score, and the MoCA score of the COPD hypoxemia group decreased more obviously (allP<0.05). The protein and mRNA levels of SAA and MCP-1 were negatively correlated with MoCA score (allP<0.05). Conclusion The protein and mRNA levels of MCP-1 and SAA in peripheral blood increase in COPD patients, and hypoxemia may be involved in cognitive dysfunction in COPD patients.
Objective To observe the relationship of serum levels of homocysteine (HCY) and chemokine C-C motifligand 2 (CCL2) with cognitive impairment in COPD patients with different degrees of emphysema. Methods Sixty-twoCOPD patients identified according to emphysema phenotype classification and admitted from January 2016 to March 2017 were recruited in the study. There were 37 cases in emphysema 1-2 grade and 25 cases in emphysema 3-4 grade. Simultaneous 30 healthy subjects undergoing physical examination were recruited as control. Montreal cognitive assessment (MoCA) scale investigation and serum HCY and CCL2 test were completed. Relationship analysis was conducted on serum HCY, CCL2 levels with cognitive impairment in the COPD patients with different degrees of emphysema. Results Compared with the 1-2 grade subgroup, the PaO2 was lower, PaCO2 was higher, the plasma HCY and CCL2 levels increased in the 3-4 grade subgroup with significant differences (all P<0.05). MoCA total score and subscores were relatively low in the COPD group with emphysema than the control group (except visuospatial ability scores in the 1-2 grade subgroup). MoCA scores were statistically lower in the 3-4 grade subgroup than those in the 1-2 grade subgroup (allP<0.05). Correlation analysis showed that HCY and CLL2 levels were negatively correlated with MoCA scores and subscores (P<0.01), and HCY and CLL2 were positively correlated (bothP<0.01). The area under the receiver operating characteristic curve of HCY and CLL2 for evaluating cognitive impairment was 0.79 and 0.97, respectively. Conclusion In patients with different degrees of emphysema phenotype, serum HCY and CCL2 levels are increased in different degree, and the degree of emphysema is closely related with cognitive dysfunction.