Abstract
AIMS/INTRODUCTION: Thrombospondin-1 (TSP-1) participates in a series of physiological and pathological processes by binding to various receptors regulating cell proliferation, adhesion and apoptosis. Elevated circulating TSP-1 is linked with diabetic vascular complications (DVC). This study aimed to determine the relationship between circulating TSP-1 levels and DVC. MATERIALS AND METHODS: A comprehensive search of PubMed, Embase, Web of Science and CNKI databases was carried out. A meta-analysis was carried out to compare circulating TSP-1 levels between diabetes patients without vascular complications (DNVC), diabetes patients with DVC and non-diabetes patients. The correlation between TSP-1 and metabolic parameters was also analyzed. Subgroup analysis was carried out according to complication type, defined as diabetic retinopathy, diabetic nephropathy and diabetic cardiovascular disease (DCVD). RESULTS: A total of eight studies were included. Compared with non-diabetes patients, diabetic patients, including DNVC and DVC, had significantly higher circulating TSP-1 levels (standardized mean difference [SMD] 2.660, 95% CI 1.17-4.145, P = 0.000). DNVC had significantly higher circulating TSP-1 levels than non-diabetes patients (SMD 3.613, 95% CI 1.607-5.619, P = 0.000). DVC had significantly higher TSP-1 levels than DNVC (SMD 0.568, 95% CI 0.100-1.036, P = 0.017). TSP-1 was significantly positively correlated with fasting plasma glucose (overall Fisher's z = 0.696, 95% CI 0.559-0.833) and HbA1c (overall Fisher's z = 0.849, 95% CI 0.776-0.923). CONCLUSIONS: Elevated circulating TSP-1 levels are closely related to DVC, especially in diabetic nephropathy and diabetic cardiovascular disease. Circulating TSP-1 detection might be helpful in the timely diagnosis and treatment of DVC.