The association between complement C1q tumour necrosis factor-related protein-1 (CTRP-1) level and metabolic syndrome.

Introduction: Complement C1q tumour necrosis factor-related protein (CTRP-1) is a member of the C1q protein superfamily that plays a role in metabolism. This retrospective study aimed to investigate associations between CTRP-1 and metabolic syndrome (MetS).

Material and methods: This study screened subjects who had undergone regular health examinations at the Physical Examination Centre in the First People's Hospital of Yinchuan (the Second Affiliated Hospital of Ningxia Medical University) between November 2017 and September 2020. The total recruited population included 430 subjects who had undergone regular health examinations, excluding 112 subjects with high glycated haemoglobin (HbA1c ≥ 7). Finally, the data of 318 participants were further analysed. Non-diabetic subjects were divided into 2 groups: one with MetS and one without MetS (controls). Serum CTRP-1 concentrations were evaluated using an enzyme-linked immunosorbent assay.

Results: A total of 318 subjects were included, among whom 176 were diagnosed with MetS (MetS group) and 142 were not (non-MetS controls). The MetS group had significantly lower CTRP-1 levels than non-MetS controls (128.51 [111.56-143.05] vs. 138.82 [122.83-154.33] ng/mL, p < 0.001). Correlation analysis showed that serum CTRP-1 levels correlated negatively with body mass index (r = -0.161, p = 0.004), waist circumference (r = -0.191, p = 0.001), systolic blood pressure (r = -0.198, p < 0.001), diastolic blood pressure (r = -0.145, p = 0.010), fasting blood glucose (FBG) (r = -0.562, p < 0.001), fasting insulin (FIns) (r = -0.424, p < 0.001), and homeostasis model assessment of insulin resistance (HOMA-IR) (r = -0.541, p < 0.001). Multiple linear regression models showed that CTRP-1 levels were associated with MetS (p < 0.01). The lipid profile area under the curve (AUC) was comparable to those for FBG and FIns, and it was significantly higher than the AUCs for demographic variables.

Conclusions: The results of this study suggest that the serum CTRP-1 level is negatively associated with MetS. CTRP-1 is a potential metabolism-related protein and is likely to be associated with lipid profiles in MetS.