Abstract: Objective To investigate the role of matrix GLA protein(MGP) in the pathogenesis of idiopathic calcium oxalate kidney stones(ICOS),and to find potential biomarkers for early diagnosis and disease evaluation.Methods A total of 120 patients admitted to our hospital from September 2021 to September 2023 were prospectively included,of which 60 patients with ICOS were in the calculus group and 60 patients without calculus were in the control group.Serum biochemical indexes and immunohistochemical scores of the two groups were detected,urinary MGP levels were determined by ELISA,and MGP mRNA and protein expression in renal papilla tissues were detected by qPCR and Western blot.The independent risk factors of ICOS were screened by Logistic regression analysis,and the prediction model was drawn by nomogram.Results Compared with control group,urinary MGP content in calculus group was decreased[(1805.91±244.44)pg/ml vs.(2014.79±252.14)pg/ml,P<0.05).Expression of MGP mRNA and MGP protein in renal papillae decreased(0.89±0.15 vs.1.00±0.00,P=0.001) and decreased(0.87±0.18 vs.1.00±0.00,P<0.05).MGP immunohistochemical scores of renal tissue were decreased [4(2-6) scores vs.6(4-8) scores,P<0.001].Multivariate analysis showed that urinary calcium(OR=1.370),urinary MGP(OR=1.127),renal papilla MGP relative expression level(OR=27.532) and renal tissue MGP immunohistochemical score(OR=1.359) were independent risk factors for ICOS.Area under ROC curve of the nomogram prediction model built based on the above factors is 0.839,indicating that the model has good differentiation ability in risk prediction.Conclusion MGP is closely related to the pathogenesis of ICOS.Urinary and renal tissue MGP levels may be potential biomarkers for early diagnosis and disease assessment of ICOS.

Key words: idiopathic calcium oxalate stones, matrix GLA protein, biomarkers, influencing factors, prediction model