Thrombospondin-2 effective marker for diabetic kidney disease

Thrombospondin-2 (TSP-2) is a new glycoprotein linked to early diabetic kidney disease (DKD) in type 2 diabetes mellitus (T2DM) patients, says an article published in BMC Nephrology. 

The multifunctional matricellular glycoprotein thrombospondin-2 has been linked to insulin sensitivity, glucose homeostasis, and estimated glomerular filtration rate. TSP-2 must be studied in relation to type 2 diabetes mellitus, as well as the potential diagnostic utility of serum TSP-2 in detecting early diabetic kidney damage. Zhenzhen Lin and colleagues employed an enzyme-linked immunosorbent test to measure blood TSP-2 levels in 494 Chinese T2DM patients. TSP-2 protein expression in the kidney and other tissues was examined using western blotting.

The key findings of this study were:

TSP-2 levels in serum were substantially greater in T2DM patients than in healthy controls. 

After controlling for age, gender, and T2DM duration, serum TSP-2 associated favorably with triglycerides, serum uric acid, creatinine, platelets, and urine albumin-to-creatinine ratio (UACR), but negatively with estimated glomerular filtration rate. 

The results of a logistic regression study revealed an independent relationship between serum TSP-2 and early DKD. 

Furthermore, when TSP-2 and age were included in a clinical model, the high UACR found at risk of early DKD rose considerably from 0.78 (95% CI 0.73-0.83) to 0.82 (95% CI 0.77-0.86, p 0.001). 

Serum TSP-2 levels were raised in db/db mice. 

TSP-2 expression was significantly higher in renal tissue from db/m and m/m mice. Furthermore, in mice, serum TSP-2 expression is associated strongly with UACR.

TSP-2 was shown to be considerably higher in T2DM patients with early DKD compared to those without early DKD, and serum TSP-2 was found to be favorably connected with renal function measures such as SUA, SCR, and UACR, but negatively linked with eGFR. TSP-2 was also found to be related with early DKD in a regression study. Furthermore, the predictive validity of TSP-2 and UACR combined for early DKD attained a more consistent value. TSP-2 has the potential to compensate for UACR deficiency. These data suggest that TSP-2 may be a new biomarker for early DKD in T2DM patients. Serum TSP-2 testing may thus be useful in predicting early renal impairment in T2DM patients in ordinary clinical practice.

Reference: 

Lin, Z., Zhang, D., Zhang, X., Guo, W., Wang, W., Zhang, Y., Liu, Z., Bi, Y., Wu, M., Lin, Z., & Lu, X. (2023). Extracellular status of thrombospondin-2 in type 2 diabetes mellitus and utility as a biomarker in the determination of early diabetic kidney disease. In BMC Nephrology (Vol. 24, Issue 1). Springer Science and Business Media LLC. https://doi.org/10.1186/s12882-023-03216-z