Urinary TGF-beta1 as an indicator of antiproteinuric response to angiotensin II receptor blocker in proteinuric renal diseases.
BACKGROUND
Angiotensin II receptor blockers (ARBs) reduce proteinuria, however, with large inter-individual variability. The present study investigated whether urinary transforming growth factor-beta1 (TGF-beta1) might predict the antiproteinuric efficacy of ARB in non-diabetic chronic renal disease.


METHODS
Non-diabetic patients with proteinuria (>1 g/day) received 50 mg of losartan daily followed by 100 mg in two treatment periods, each lasting 12 weeks. Clinical parameters and urinary TGF-beta1 levels were measured at baseline and during the treatment period.


RESULTS
In the whole group of patients, losartan treatment effectively decreased proteinuria. However, considerable differences existed among individual antiproteinuric responses. Good (n=34) or low (n=15) responders showed average proteinuria reduction of 69% or 17% from baseline, respectively. Both groups showed similar baseline biochemical and renal parameters and comparable degree of mean arterial blood pressure (MAP) reduction. However, the low responders were older and showed significantly higher baseline urinary TGF-beta1 levels. On multiple regression analysis, age, baseline urinary TGF-beta1 and % reduction in urinary TGF-beta1 and % reduction in MAP significantly predicted antiproteinuric response to losartan therapy.


CONCLUSIONS
The present data suggest that the determination of baseline urinary TGF-beta1 could be an useful indicator of short-term antiproteinuric response to ARB treatment in non-diabetic nephropathy.
Park
Hyeong Cheon
HC
Department of Internal Medicine, Yonsei University College of Medicine, Seoul, South Korea. amp97@yumc.yonsei.ac.kr
Choi
Hoon Young
HY
Kim
Beom Seok
BS
An
Hye Rim
HR
Lee
Jae Sung
JS
Ha
Sung Kyu
SK
Han
Dae Suk
DS
D000328:Adult; D047228:Angiotensin II Type 1 Receptor Blockers / Q000627:therapeutic use*; D001794:Blood Pressure / Q000187:drug effects; D005260:Female; D006801:Humans; D019808:Losartan / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D011507:Proteinuria / Q000188:drug therapy* / Q000652:urine; D053773:Transforming Growth Factor beta1 / Q000652:urine*
D047228:Angiotensin II Type 1 Receptor Blockers; D053773:Transforming Growth Factor beta1; D019808:Losartan