Expression and clinical significance of platelet-derived miR-145-5p and miR-6805-3p in diabetic kidney disease patients

Objectives: Approximately 30-40% of diabetes mellitus (DM) patients will progress to diabetic kidney disease (DKD) and eventually cause end-stage renal disease (ESRD) during their disease course; therefore, early recognition and prevention of DKD is critical. The detection based on biomarkers derived from blood samples has the characteristics of easy availability and affordability. In addition to participating in thrombosis and hemostasis, platelets also have important secretion functions. Our research aims to identify novel platelet miRNA candidates for DKD diagnosis and to explore their clinical significance. Methods and results: miR-145-5p and miR-6805-3p were selected for further evaluation based on their differentially expressed status between DM and DKD subjects, as determined by both bioinformatic and RT-qPCR analyses, and their expression was significantly higher than that in healthy control and DM groups. Correlation analyses revealed that the levels of platelet-derived miR-145-5p and miR-6805-3p were positively associated with uric acid (UA), serum creatinine, blood urea nitrogen (BUN), urine albumin-to-creatinine ratio (UACR), cystatin C, platelet to lymphocyte ratio (PLR), and neutrophil to lymphocyte ratio (NLR), and negatively correlated with estimated glomerular filtration rate (eGFR), albumin, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), blood glucose, and hemoglobin A1c (HbA1c). In addition, miR-145-5p expression level was positively correlated with globulin; the levels of miR-6805-3p but not miR- 145-5p were increased in DKD patients with higher staging. Conclusion: Our research suggests that platelet-derived miRNAs may be promising biomarkers for diagnosing DKD and monitoring its progression.