糖尿病患者的Tamm-Horsfall蛋白糖化會降低對晶體聚集抑制的功能

盧艷金^1,3、曾一修^1,2

亞東紀念醫院 外科部 ¹創傷科，²泌尿科; ³醫學研究部

Glycated Tamm-Horsfall protein of diabetes patients decrease the function on crystal aggregation inhibition

Yen-Chin Lu^1,3, Yi-Shiou Tseng^1,2

Divisions of Traumatology¹ and Urology², Department of Surgery, Far Eastern Memorial Hospital, New Taipei City, Taiwan

Department of Medical Research³, Far Eastern Memorial Hospital, New Taipei City, Taiwan

Purpose: Tamm-Horsfall protein (THP) is the most abundant protein in human urine, it plays an important role in preventing kidney stone formation. It has been studied that stone formers with diabetes mellitus (DM) had lower urine THP production, but the function of crystal aggregation inhibition from THP is still unknown. Advanced glycation end products (AGEs) are nonenzymic activities that are formed by proteins, lipids, and amino acids with sugar. Our study aims to investigate the different function of THP on crystal aggregation between stone formers with and without diabetes.

Materials and Methods: There were 52 non-DM and 42 DM stone formers included. Salt precipitation method was used to isolate THP from 24-hour urine. Urine THP amount were measured by ELISA to estimate the daily amount, whereas AGEs amount were measured by fluorescent detection. The aggregation test was the interaction between calcium oxalate monohydrate (COM) crystal and THP by a spectrophotometer (optical density at λ620 nm).

Results: The daily extraction amount of urine THP was reported to be higher in non-DM stone formers than in DM stone formers (13.96 ± 1.14 mg/day vs 9.77 ±1.11 mg/day, P < 0.05). DM stone formers had a significantly lower function of aggregation inhibition than non-DM stone formers (-3.01 ± 2.00%vs 6.53 ± 1.74%, P < 0.001). AGE levels of THP in the DM group were not different from the non-DM group (633.24 ± 77.42 AU/mg vs. 563.85 ± 47.22 AU/mg).

Conclusions: According to our findings, stone formers with DM have impaired THP function for crystal aggregation inhibition. Impaired function of aggregation inhibition indicates more crystal formation and higher recurrent rate in kidney stone disease. Glycation has a greater impact on THP function in DM stone formers than in non-DM stone formers.