Abstract: TH-PO657

Proteomic Study Revealed the Elevation of Urinary Alpha-1-Microglobulin/Bikunin Excretion in Nephrolithiasis Familial Members

Session Information

  • Pediatric Nephrology
    November 02, 2017 | Location: Hall H, Morial Convention Center
    Abstract Time: 10:00 AM - 10:00 AM

Category: Developmental Biology and Inherited Kidney Diseases

  • 403 Pediatric Nephrology

Authors

  • Dissayabutra, Thasinas, Chulalongkorn University, Pathumwan, Bangkok, Thailand
  • Pisitkun, Trairak, Chulalongkorn University, Pathumwan, Bangkok, Thailand
  • Tosukhowong, Piyaratana, Chulalongkorn University, Pathumwan, Bangkok, Thailand

Group or Team Name

  • Biochemistry and Molecular Disease Research Unit
Background

Several literatures demonstrated higher incidence of urinary tract stone formation in familial members of nephrolithiasis (NL), although no responsible gene was established. Our previous studies revealed elevated urinary excretion rate of calcium, phosphate, albumin and protein as well as diminished urinary citrate and sulfated glycosaminoglycan excretion in non-stone-forming children of NL patients compare with normal children. These disorders were similarly observed in NL patients comparing with general population but in the greater severity pattern. Hence, to indicate which proteins were over-excreted in children with NL parents, we investigated proteomic profile in the susceptible children comparing with stone patients and general population.

Methods

Fourteen NL patients (N) and 29 of their children (NC), 26 healthy volunteers (V) and 28 of their children (VC) were enrolled. The 24-hour urine were collected. Except for NL, participants were screened for hematuria by urine strip test. Then, urine of NC and VC (children group) were used for proteomic study by mass spectrophotometry (LC-MS). Alpha-1-microglobulin/bikunin [AMBP] was subsequently measured in all participants using ELISA.

Results

According to proteomic profiles, the urinary excretion rate of 29 proteins were higher in non-stone-forming NC than VC. Among these, many proteins were previously reported to be associated with NL, such as AMBP, α1-antitrypsin, serotransferrin, trefoil factor, prothrombin, vitronectin, etc. Our study observed the elevation of AMBP excretion in both NL patients (28.3+41.2 vs 10.2+20.1 mg/day, p=0.048) and their children (25.2+27.8 vs 10.2+10.6 mg/day, p=0.011.)

Conclusion

Urinary excretion rate of several stone-related proteins, including AMBP, appeared to be elevated in NL family even in members who yet to develop stone. Our results indicated that these abnormal urinary proteins may be the risks for high incidence of NL in familial members, and may be heritable. Further study aims to validate other susceptible urinary proteins, the pathogenesis and inherited pattern.

Funding

  • Government Support - Non-U.S.