Leslie Kushner

IBUPROFEN COMBINED WITH ANTIBIOTICS SUPPRESSES RENAL SCARRING DUE TO ASCENDING PYELONEPHRITIS IN RATS

PURPOSE In acute pyelonephritis renal scarring may be decreased by immediate antibiotic therapy. Unfortunately in children there is often a delay in starting treatment, which increases the likelihood of renal scarring. In rodents immediate antibiotic therapy is effective for preventing renal scar formation resulting from experimentally induced pyelonephritis. However, the same treatment beginning 72 hours after infection does not prevent renal scarring in this paradigm. We examined whether delayed administration of the nonsteroidal anti-inflammatory agent ibuprofen only or combined with antibiotics suppresses renal scarring in a model of ascending pyelonephritis in rats. MATERIALS AND METHODS An inoculum of 5x10(9) organisms per ml. of Escherichia coli strain BH-5 was instilled into the bladder of rats and the urethra was occluded for 4 hours. Groups of animals were and were not treated with 15 mg./kg. cefadroxil or 10 mg./kg. ibuprofen given twice daily for 5 days, or the 2 drugs combined. Treatment began 72 hours after inoculation. In an additional group of rats sterile phosphate buffered saline was instilled into the bladder. In each rat the kidneys were examined grossly and microscopically 6 weeks later. RESULTS Combined antibiotics and ibuprofen significantly inhibited gross renal scarring compared with no treatment or antibiotics only (p<0.05). No difference in renal scarring was detected in animals that received no treatment versus those that received antibiotics or ibuprofen only (p>0.05). CONCLUSIONS Renal scarring resulting from acute pyelonephritis in this rat model is not decreased by delayed treatment with antibiotics only. The addition of ibuprofen to antibiotic therapy is effective for decreasing renal scarring due to acute pyelonephritis even when treatment is delayed for 72 hours.

ENDOPYELOTOMY FAILURE IS ASSOCIATED WITH REDUCED TRANSFORMING GROWTH FACTOR-beta

PURPOSE Approximately 15% of patients with ureteropelvic junction obstruction have endopyelotomy failure and require an additional surgical procedure to remove the obstruction. Transforming growth factor-beta (TGF-beta), a cytokine which stimulates mesenchymal cell proliferation and extracellular matrix deposition, increases in the renal pelvis in response to obstruction. However, TGF-beta also is implicated in smooth muscle regeneration and wound healing. To understand the pathophysiology of ureteropelvic junction obstruction and determine why endopyelotomy fails in some obstructed ureteropelvic junctions, TGF-beta expression in obstructed and normal ureteropelvic junction segments was compared. MATERIALS AND METHODS Immunohistochemical staining using a rabbit polyclonal anti-TGF-beta was performed on deparafinfized 4 microm. sections of paraffin blocked ureteropelvic junction segments. Human obstructed ureteropelvic junction segments were removed during primary pyeloplasties (11) and secondary pyeloplasties after endopyelotomy failure (11). Normal ureteropelvic junction segments were removed during nephrectomy for purposes unrelated to obstruction (11). Grading on a scale of 0 to 4 was performed by a physician blinded to the source of the specimen. RESULTS Mean TGF-beta expression plus or minus standard error of the mean was significantly increased (p <0.02) in obstructed ureteropelvic junctions from primary pyeloplasties (2.6+/-0.7) compared to normal ureteropelvic junctions (1.6+/-0.7), as expected. However, TGF-beta expression in the endopyelotomy failure group (1.8+/-0.6) was not significantly different from that in normal ureteropelvic junctions and was significantly lower (p <0.05) than that in obstructed ureteropelvic junctions from primary pyeloplasties. CONCLUSIONS Obstructed ureteropelvic junctions in cases of endopyelotomy failure have decreased expression of TGF-beta compared with other obstructed ureteropelvic junctions. These data suggest that an elevation of TGF-beta in obstructed ureteropelvic junctions may be necessary for successful tissue repair after endopyelotomy.

Endopyelotomy Failure Is Associated with Reduced Urinary Transforming Growth Factor-β1 Levels in Patients with Upper Urinary Tract Obstruction

BACKGROUND AND PURPOSE We previously demonstrated that obstructed ureteropelvic junction (UPJ) segments from patients who had secondary pyeloplasty after endopyelotomy failure expressed transforming growth factor-beta1 (TGF-beta1) at levels significantly lower than patients who had primary pyeloplasty. In order to determine whether these differences in secreted TGF-beta1 are detectable preoperatively in the urine, the TGF-beta1 concentration of urine from patients undergoing endopyelotomy was determined and compared with that from subjects without urologic disease. MATERIALS AND METHODS Bladder and renal pelvic urine from the obstructed side was obtained from patients (N = 34) undergoing primary endopyelotomy for UPJ obstruction. Bladder urine was also obtained from sex- and age-matched patients (N = 26) having no evidence of urinary tract obstruction. The TGF-beta1 concentration was determined by ELISA and normalized to the creatinine concentration. RESULTS The bladder urine TGF-beta1 concentration was significantly (P < 0.02) higher in patients with UPJ obstruction (86.1+/-20.5 pg/mg of creatinine) than in those without obstruction (29.7+/-8.0 pg/mg creatinine). The TGF-beta1 concentration in the bladder urine of patients who underwent endopyelotomy and later returned because of UPJ obstruction (25.7+/-12.3 pg/mg of creatinine; N = 6) was not significantly different from the value in unobstructed patients but was significantly lower (P < 0.01) than in patients for whom endopyelotomy was successful (100+/-24.29 pg/mg of creatinine; N = 28). The renal pelvic urinary TGF-beta1 concentration was higher in patients for whom endopyelotomy was successful (772+/-490.1 pg/mg of creatinine) than in patients who underwent endopyelotomy and later returned because of UPJ obstruction (126.1+/-41.9 pg/mg of creatinine). CONCLUSIONS These data suggest that preoperative concentration of TGF-beta1 in the bladder urine of patients with UPJ obstruction who fail endopyelotomy is not significantly different from that in subjects with no urologic disease and significantly lower than in those patients for whom endopyelotomy is successful. Thus, the preoperative bladder urine concentration of TGF-beta1 may assist in selecting patients for this operation, although further investigation is necessary.

Unilateral Nephrectomy Induces the Expression of the Wilms Tumor Gene in the Contralateral Kidney of the Adult Rat

PURPOSE The tumor suppressor gene WT-1 encodes a nuclear deoxyribonucleic acid binding protein that is a transcriptional regulator. This gene is commonly deleted or defective in Wilms tumors and the Denys-Drash syndrome. Recently WT-1 was demonstrated to be essential for the development of the urogenital tract. We determined whether we could induce WT-1 expression in mature kidneys induced to grow by performing contralateral nephrectomy in mature rats. MATERIALS AND METHODS Northern analysis with a 32phosphorus-labeled antisense riboprobe synthesized by in vitro transcription of a 731 bp complementary deoxyribonucleic acid insert spanning exons 1 to 7 of the rat WT-1 in a pT7 Blue vector was used to demonstrate the expression of WT-1 in the developing and adult Sprague-Dawley rat kidney. RESULTS Transcript levels of WT-1 in the rat kidney decreased from day 0 (day of birth) to day 16, after which WT-1 transcripts were undetectable in the normal rat kidney. Unilateral nephrectomy in the adult male Sprague-Dawley rat (250 to 300 gm.) induced the expression of WT-1 ribonucleic acid in the contralateral kidney to detectable levels by Northern analysis 0.25 hours after nephrectomy. Subsequently levels of WT-1 ribonucleic acid decreased progressively to undetectable by 3 hours after nephrectomy. Expression of this gene was not detected in the normal kidneys of adult rats or sham operated adult rats. CONCLUSIONS These data suggest that the WT-1 gene product is involved in normal renal growth in the adult and developing rat kidney.

Expression of c-met and WT-1.

Protooncogenes and tumor-suppressor genes are two types of genes associated with cancer development.