Correlation between urinary exosomal miR-155 and the onset and severity of type 2 diabetic kidney disease / 中华肾脏病杂志

ABSTRACT

Objective:To explore the relationship between urinary exosomal microRNA (exo-miR) - 155 in patients with type 2 diabetes mellitus (T2DM) and the onset and severity of diabetic kidney disease (DKD).Methods:From January to May 2019, 5 patients with T2DM normoalbuminuria and 5 patients with type 2 DKD were recruited from the Department of Endocrinology and Metabolism of Chongming Hospital of Shanghai Health Medical College as a microRNA screening cohort. Urine samples were collected to extract urinary exosomes, and the urine exo-miR spectrum was detected and analyzed using the miRCURY LNA array. From June 2019 to October 2022, 351 patients with T2DM who met the enrollment criteria and were matched by age and sex were included in the validation cohort in the Department of Endocrinology and Metabolism of the hospital. Patients were divided into 3 groups according to urinary albumin/creatinine ratio (UACR): normoalbuminuria group (UACR<30 mg/g, n=143), microalbuminuria group (30 mg/g≤UACR≤300 mg/g, n=171) and macroalbuminuria group (UACR>300 mg/g, n=37). According to DKD diagnostic guidelines, microalbuminuria group and macroalbuminuria group were classified into DKD group. Real-time fluorescence quantitative PCR was used to detect the expression level of exo-miR-155 in urine. Results:The results of transmission electron microscopy, nanoparticle tracking analysis, and Western blotting showed that the extraction of exosome vesicles was successful. In the screening cohort, according to the screening criteria of P<0.05 and fold changes (FC)>1.5, 226 differentially expressed miRNAs were identified from the urinary exosomes of the DKD group compared to the T2DM group. Among them, miR-155 ranged highest (FC=32.75, P<0.001). In the validation cohort, compared with the normoalbuminuria group [0.76 (0.55, 0.95)], the macroalbuminuria group [1.84 (1.18, 2.42)] had the most significant increase in urinary exo-miR-155 level ( Z=-7.411, P<0.001), followed by the microalbuminuria group [0.86 (0.69, 1.25)] ( Z=-4.092, P<0.001), and the urinary exo-miR-155 level in the macroalbuminuria group was significantly higher than that in the microalbuminuria group ( Z=-5.841, P<0.001). The correlation analysis showed that urinary exo-miR-155 level was positively correlated with UACR ( r s=0.329, P<0.001) and negatively correlated with estimated glomerular filtration rate ( r s=-0.249, P=0.015). The results of receiver operating characteristic curve analysis showed that the area under the curve of urinary exo-miR-155 level predicted DKD progression in T2DM patients was 0.892 (95% CI 0.859-0.925), corresponding cutoff value was 0.982, and the sensitivity and specificity were 71.9% and 87.7%, respectively. Multivariate logistic regression analysis showed that urinary exo-miR-155≥0.982 was an independent risk factor for progression to DKD in T2DM patients ( OR=3.310, 95% CI 1.981-5.530, P<0.001). Conclusion:The expression level of urinary exo-miR-155 is increased in T2DM patients with microalbuminuria and macroalbuminuria, which is related to the degree of albuminuria, and can be used as a predictive marker to identify potential DKD.