Association between residential greenness and coronary heart disease: A proteomics and miRNA microarray analysis

Greenness has been linked to cardiovascular disease. However, the specific biological mechanisms through which greenness impacts coronary heart disease (CHD) remain unclear. We aim to explore the underlying epigenetic mechanisms linking greenness and CHD by using proteomics and miRNA microarray. A total of 2387 participants were included in the population study, 816 of whom were diagnosed with CHD. Residential greenness exposure was characterized using the normalized difference vegetation index (NDVI). Generalized additive models and restricted cubic splines investigated the association between greenness and CHD. Mediation analysis examined whether cardiovascular metabolic risk factors (blood pressure, inflammation indicators, and glucose) mediated the association. After proteomics and miRNA microarray screening, Elisa and qRT-PCR validated selected proteins (THBS1, FCN3, and LTBP1) and miRNAs (miR-671-5p, miR-124-3p, and miR-379-5p) in CHD. Among these, LTBP1 and miR-379-5p showed significant differential expression (P < 0.05) and were examined as potential molecular mediators. Higher greenness exposure within a 1000-m area was associated with a lower risk of CHD (OR: 0.86, 95 % CI: 0.81, 0.92). Systolic blood pressure (6.32 % [95 % CI: 1.49 %, 13.12 %]), lymphocyte (10.98 % [95 % CI: 3.76 %, 22.00 %]), monocyte (9.94 % [95 % CI: 3.42 %, 20.87 %]), and fasting blood glucose (3.41 % [95 % CI: 0.56 %, 7.84 %]) mediated this association. LTBP1 and miR-379-5p were differentially expressed in CHD and mediated 7.19 % [95 % CI: 0.01 %, 23.37 %] and 20.03 % [95 % CI: 2.85 %, 69.71 %] of greenness effect on CHD, respectively. Combining the population study and experiments, we found that miR-379-5p and LTBP1 may jointly modulate vascular constriction and immune inflammation in the association between greenness and CHD.