Abstract: Objective To explore the correlation between the levels of serum thioredoxin-interacting protein (TXNIP) and Klotho and diabetic cardiomyopathy(DCM) in the elderly. Methods From May 2018 to March 2020, 67 elderly patients with DCM were selected as DCM group; At the same time, 72 elderly patients with diabetic mellitus (DM) without cardiomyopathy were selected as DM group, in addition, 84 cases of elderly healthy people were treated as normal control group. The expression of Klotho mRNA was detected by real-time fluorescence quantitative PCR (qRT-PCR); The level of serum TXNIP was detected by enzyme-linked immunosorbent assay (ELISA); The correlation between the levels of serum Klotho mRNA, TXNIP and serum parameters in the patients with DCM was analyzed, and the influencing factors of DCM were analyzed by Logistic regression. Results The levels of serum TXNIP, brain natriuretic peptide (BNP), cardiac troponin I (cTnI), tissue inhibitor of matrix metalloproteinase-1 (TIMP-1), atrial natriuretic peptide (ANP) in DCM group were higher than those in DM group and normal control group, and the levels of Klotho mRNA and matrix metalloproteinase-2 (MMP-2) were lower than these in DM group and normal control group (P<0.05). There was a negative correlation between serum Klotho mRNA and TXNIP in the patients with DCM (r=-0.646, P<0.05); Klotho mRNA (TXNIP) was positively (negatively) correlated with MMP-2 (P < 0.05), and negatively (positively) correlated with BNP, cTnI, TIMP-1 and ANP (P < 0.05). Logistic regression showed that TXNIP and ANP were the independent risk factors of DCM (P < 0.05), and Klotho mRNA was the protective factor of DCM (P < 0.05). Conclusions TXNIP is highly expressed in the serum of the patients with DCM, while Klotho is lowly expressed, which may have a high reference value for clinical application.

Key words: diabetic cardiomyopathy, serum, thioredoxin-interacting protein, Klotho