陳修聖 邱文祥

台北市立聯合醫院仁愛院區

國立陽明大學 醫學院 泌尿學科

Saint Shiou-Sheng Chen, Allen W. Chiu,

Department of Urology, National Yang-Ming University School of Medicine

Division of Urology, Taipei City Hospital Renai Branch, Taipei, Taiwan

 

To evaluate the change of oxidative stress before and after extracorporeal shock wave lithotripsy (ESWL) for patients with ureteral stone.

Forty patients with ureteral stone and receiving ESWL were recruited in this study. The parameters for comparison included severity of hydronephrosis (mild, moderate and severe), stone size, shock wave numbers and KV, age, and body mass index (BMI). The oxidative stress and antioxidant capacity were evaluated by measuring malondialdehyde (MDA), mitochondrial DNA (mtDNA) copy number and total capacity of antioxidants (TOA) in the blood. The data were correlated with serum creatinine, which were measured before and immediately after ESWL in all patients. Malondialdehyde (MDA), one of the lipid peroxidation products, in blood plasma was measured by reaction with a chromogenic regent nmethyl-2-phenylindole (NMPI) to form an intensely colored carbocyanine dye with a maximum absorption at 586 nm by using the MDA-586 kit (Oxis Research, Portland, OR, USA). An MDA standard curve was established by using the MDA samples at the concentration range of 0-50 M. The copy number of mtDNA in leukocytes was measured by a real-time PCR technique using the LightCycler FastStart DNA Master SRBR Green I according to a method described previously. The relative copy number of mtDNA was measured by normalization of the crossing points (Cp) in quantitative PCR curves between the ND1 and 18S rRNA genes using the RelQuant software (Roche Applied Sciences, Mannheim, Germany). The TOA in serum was performed by the PAO kit from Japan Institute for the Control of Aging (Nikken SEIL Co., Fukuroi, Japan) according to the manufacturer’s instruction. The antioxidant power of the sample was estimated by multiplying the corresponding uric acid concentration by 2189.

Results:

Serum creatinine increased (1.22 + 0.23 vs. 1.43 + 0.25 mg/dL), MDA (16.3 + 2.9 vs. 24.1 + 6.3 M) was increased and TOA (159.7 + 55.2 vs. 78.6 + 34.3 mM) decreased in all the patients immediately after ESWL compared with the data before ESWL. Thirteen patients with larger ureteral stone (>1cm, group A) had significantly higher MDA (24.9 + 2.8 vs. 22.1 + 5.1 M), lower mtDNA copy number (0.24 + 0.12 vs. 0.34 + 0.12), and lower TOA (61.7 + 29.2 vs. 76.4 + 32.5 mM) immediately after ESWL than did those (27 patients) with smaller stone (<1cm, group B). By multiple regression, larger ureteral stone, higher shock wave numbers and KV were associated with higher oxidative stress and lower antioxidant capacity immediately after ESWL. Besides, negative correlation was found between oxidative stress and renal function immediately after ESWL.

An increase of MDA and decrease of TOA in blood in all the patients immediately after ESWL, which might induce renal damage. Moreover, the oxidative stress levels in blood was higher and antioxidant capacity was lower in patients who had larger ureteral stone (>1cm), severe hydronephrosis and receive higher shock wave numbers (>4000) and KV (>17).