Transforming growth factor-beta1 in the urine of young children with urinary tract infection

Estimation of the relationship between the polymorphisms of selected genes: ACE, AGTR1, TGFβ1 and GNB3 with the occurrence of primary vesicoureteral reflux

PURPOSE

Etiopathogenesis of VUR is composite and not fully understood. Many data indicate the importance of genetic predisposition. The aim of this study was to establish the relationship of selected polymorphisms: 14094 polymorphism of the ACE, polymorphism rs1800469 of TGFβ-1, rs5443 gene polymorphism of the GNB3 and receptor gene polymorphism rs5186 type 1 AGTR1 with the occurrence of the primary vesicoureteral reflux.

MATERIAL

The study included 190 children: 90 with the primary VUR confirmed with the voiding cystourethrogram and excluded secondary VUR and a control group of 100 children without a history of the diseases of the genitourinary tract.

METHODS

The study was planned in the scheme: "tested case versus control." Genomic DNA was isolated from the leukocytes of peripheral blood samples. The results were statistically analyzed in the Statistica 10 using χ ² test and analysis of the variance Anova.

RESULTS

Any of the four studied polymorphisms showed no difference in the distribution of genotypes between patients with primary vesicoureteral reflux and the control group. In patients with VUR and TT genotype polymorphism rs5443 GNB3 gene, the glomerular filtration rate was significantly higher than in patients with genotype CC or CT.

CONCLUSIONS

(1) No relationship was found between the studied polymorphisms (14094 ACE gene, rs1800469 gene TGFβ1, GNB3 gene rs5443, rs5186 AGTR1 gene) and the occurrence of primary vesicoureteral reflux. (2) TT genotype polymorphism rs5443 GNB3 gene may be a protective factor for the improved renal function in patients with primary vesicoureteral reflux in patients with genotype CC or CT.

Urine interleukin-6, interleukin-8 and transforming growth factor β1 in infants with urinary tract infection and asymptomatic bacteriuria

INTRODUCTION

Urinary tract infection (UTI) occurs in 1.1% of girls and 1.4% of boys during the first year of life. Asymptomatic bacteriuria (ABU) is usually detected incidentally in 0.9% of girls and 2.5% of boys at this age. The aim of the study was to assess the usefulness of measurement of pro-inflammatory urine interleukin (IL)-6 and IL-8 concentrations and anti-inflammatory transforming growth factor β1 (TGF-β1) level in infants with febrile UTI, non-febrile UTI and ABU.

MATERIAL AND METHODS

A total of 35 children, mean age 6.14 ±3.47 months, were divided into three groups: group I - febrile UTI (n = 13), group II - non-febrile UTI (n = 13) and group III - ABU (n = 9). At the time of enrollment urine IL-6, IL-8, TGF-β1 and serum C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and white blood cell count (WBC) were measured. Renal ultrasound was performed in all children, 99mTc-dimercaptosuccinic acid scintigraphy (DMSA) and voiding cystourethrography in children with UTI.

RESULTS

Urine concentrations of IL-6 and IL-8 were significantly higher in febrile UTI compared to those with non-febrile UTI and ABU (p < 0.5, p < 0.01) and positively correlated with CRP, ESR and WBC (p < 0.01). Urine levels of TGF-β1 were significantly higher in children with febrile UTI compared to those with ABU (p < 0.05) and positively correlated with WBC (p < 0.01). Inflammatory changes in the DMSA scan were detected in 66.6% of children with UTI. No significant difference in frequency of an abnormal DMSA scan compared to a normal scan was found in groups with febrile and non-febrile UTI. No relations between urine cytokines, systemic inflammatory markers and changes in DMSA scan were observed. The cutoff value for detection of inflammatory changes in the DMSA scan for IL-8 was 120 pg/mg creatinine (Cr) and 40 pg/mg Cr for TGF-β1. Based on this value, the sensitivity for IL-8 was 58.3%, specificity 100% and for TGF-β1 66.7% and 83.7%, respectively.

CONCLUSIONS

We found significant differences in children with febrile UTI and ABU regarding urine IL-6, IL-8 and TGF-β1 levels. Urine cytokines and systemic inflammatory markers do not differentiate between upper and lower UTI in infants.

Laminin and transforming growth factor beta-1 in children with vesicoureteric reflux

High-grade vesicoureteric reflux (VUR) promotes the development of renal nephropathy (RN) due to scar formation. This process involves transforming growth factor beta-1 (TGF beta(1)), which stimulates production of the extracellular matrix proteins, including laminin (LN). The aim of the study was to assess LN and TGF beta(1) concentration according to VUR grade. The study group (1) consisted of 54 patients aged 6.23 +/- 4.15 years with VUR, including: A, 19 with grade II; B, 19 with grade III; and C, 16 with grades IV or V reflux. The control group (2) contained 27 healthy patients aged 6.76 +/- 4.02 years. LN and total TGF beta(1) concentrations in serum and urine were determined by the immunoenzymatic (EIA) method. To assess total serum TGF beta(1) levels, we used a solid-phase enzyme-linked immunosorbent assay (ELISA). Both serum and urinary levels of LN and TGF beta(1) in VUR patients were higher compared with controls (p < 0.05). The highest urinary concentration of LN and TGF beta(1) was found in subgroup C. A positive correlation was noted between urinary TGF beta(1) and LN. Increased TGF-beta(1) and LN levels in urine of high-grade VUR children suggests a potential role in fibrogenesis. Further trials are needed to investigate the role of serum and urinary LN level in VUR children.

Genetic control of VEGF and TGF-beta1 gene polymorphisms in childhood urinary tract infection and vesicoureteral reflux

We investigated whether genetic polymorphisms of vascular endothelial growth factor (VEGF) and transforming growth factor-beta1 (TGF-beta1), potential candidate genes in the pathogenesis of urinary tract infection (UTI) and vesicoureteral reflux (VUR), are associated with the susceptibility to UTI and VUR, and renal scarring. We recruited 89 controls and 86 UTI and 58 VUR children. The UTI group was subdivided into two groups according to renal scarring. Two polymorphisms of VEGF and three of TGF-beta1 genes were investigated by using PCR-restriction fragment length polymorphism analysis. In both UTI and VUR groups, there was an increase in frequency of the VEGF -460 CC (control, 4.3; UTI, 15.9; VUR, 17.8%; p < 0.05), TGF-beta1 -509 CC (control, 8.7; UTI, 34.6; VUR, 35.1%; p < 0.001), and TGF-beta1 -800 GG genotypes (control, 19.1; UTI, 40.5; VUR, 40.4%; p < 0.05). An increase in the TGF-beta1 +869 CC (scar-positive, 35.4; scar-negative, 10.3%; p < 0.05) and a decrease in the +869 TC genotype (scar-positive, 29.2; scar-negative, 55.2%; p < 0.05) were observed in the scar-positive subjects. There were no differences in +405 VEGF genotype frequencies. The VEGF T-460C and the TGF-beta1 C-509T, G-800A, and T869C polymorphisms could be genetic markers of the process of UTI and VUR.

Serum and urine interleukin-6 and transforming growth factor-beta1 in young infants with pyelonephritis

BACKGROUND

Cytokines are involved both in the acute response during pyelonephritis and in the progression to renal scarring. The aim of the present study was to assess the pro-inflammatory interleukin-6 (IL-6) and the anti-inflammatory pro-fibrotic transforming growth factor-beta1 (TGF-beta) in very young infants with pyelonephritis.

METHODS

Serum and urine concentrations of IL-6 and TGF-beta1 were determined by enzyme immunoassay in infants with acute pyelonephritis before antibiotic treatment and in infants with non-renal fever. IL-6 was studied in 12 infants with pyelonephritis and in eight with non-renal fever (median ages, 2 months for both groups). TGF-beta1 was studied in 11 infants with pyelonephritis and in nine with non-renal fever (median ages, 2 and 4 months, respectively).

RESULTS

No significant differences were documented in serum concentrations of IL-6 and TGF-beta1 between patients and controls. Urine IL-6 levels were significantly higher in infants with pyelonephritis than in controls (medians, 147 and 21.4 pg/ml, respectively; P = 0.0106). The urine levels of TGF-beta1 were lower in infants with pyelonephritis than in controls, although not significantly (medians, 6.12 and 11.0 ng/ml, respectively; P = 0.0705).

CONCLUSIONS

Our findings confirm the implication of IL-6 but not of TGF-beta1 in the pathogenesis of the early stages of pyelonephritis in young infants. Tauhe role of the pro-fibrotic TGF-beta1 in the development of renal scarring deserves further investigation.