TNF and inflammation: In addition to IL-1β (log2FC = 1.34), the RNA-sequencing results also showed that tumour necrosis factor-α (TNF-α) expression (log2FC = 3.18) was also significantly elevated in heart tissues of DCM mice, which is consistent with our previous findings that levels and gene expression of TNF-α and IL-1β were significantly elevated in serum and myocardial tissues of db/db mice, and they were mediated cardiac inflammation and fibrosis through immune responses [44].