interleukin-8 and Nephrotic-Syndrome

Primary nephrotic syndrome (PNS) is one of the common renal diseases in children, the pathogenesis of which is unclear. Evidences suggested that the proteinuria of NS is associated with the increased expression of the interleukin-8 (IL-8) genes. The purpose of the study was to evaluate the serum concentration and mRNA expression of IL-8 before and after the methylprednisolone pulse therapy (MPT) in PNS.. Thirty children with PNS diagnosed from December 2000 to October 2001 were enrolled in this study (patients group). They were not treated with glucocorticoid at least within the recent 3 months. The children aged from 1.5 to 14 years (mean 8.5 years), and included 24 boys and 6 girls. Eighteen healthy children were selected as control group after physical examination. The children in control group aged from 2 to 14 years (mean 8 years) and included 13 boys and 5 girls. All patients were treated with MPT intravenously (30 mg/kg) for successive 3 days followed by oral prednisone. The serum protein level of IL-8 was measured by ELISA according to the manufacturer's instructions. Human IL-8 ELISA kit was purchased from Jingmei corporation Shenzhen, China. And the concentration was obtained after drawing the standard curve. The expression of IL-8 gene was detected with RT-PCR method. The important reverse transcription reagent kit and Trizol reagent were all bought from GIBCO BRL, USA. Statistical analysis of rank sum test was adopted for data processing.. Comparison of the serum IL-8 level in the same patient before and after the therapy showed significant difference [29.59 (7.14-352.08) ng/L vs. 10.80 (4.27-77.86) ng/L, u = 4.26, P < 0.01]. The serum level in patient group before the therapy increased obviously in comparison to the level of the control group [10.37 (5.46-33.31) ng/L, u = 4.53 P < 0.01]. The serum level of IL-8 in patient group after the therapy also showed significant difference compared to the control group (u = 2.73 P < 0.01). The mRNA expression of IL-8 in the same patient before and after therapy showed significant difference [0.862 (0.776-0.95) vs. 0 (0-0.754), u = 3.902 P < 0.01].. IL-8 may be involved in the pathogenesis of PNS because of the significant increase of the serum IL-8 level and PBMC IL-8 mRNA expression in nephrotic syndrome children. Methylprednisolone pulse therapy in PNS was able to inhibit the protein production and PBMC mRNA expression of IL-8, so the therapeutic mechanism of MPT in PNS might be associated with the inhibition of IL-8 expression.

Topics: Adolescent; Child; Child, Preschool; Enzyme-Linked Immunosorbent Assay; Female; Gene Expression; Glucocorticoids; Humans; Infusions, Intravenous; Interleukin-8; Male; Methylprednisolone; Nephrotic Syndrome; Pulse Therapy, Drug; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Treatment Outcome

Low-density lipoprotein apheresis (LDL-A) treatment combined with steroids demonstrated significant improvement of nephrotic proteinuria in steroid- or immunosuppressive-resistant patients from focal and segmental glomerulosclerosis (FGS). The mechanisms of the effect of LDL-A in nephrotic syndrome (NS) are unknown, but a reduction in inflammatory cytokines and chemokines secreted from macrophages has been supposed.. Serum levels of interleukin (IL)-8, tumor necrosis factor-alpha (TNF-alpha), and monocyte chemoattractant protein-1 (MCP-1) were measured by enzyme-linked immunosorbent assay in 27 patients with NS [13 with FGS and 14 with minimal change nephrotic syndrome (MCNS)] before and after LDL-A and in 13 age-matched, healthy controls. We also selected three FGS patients who were resistant to steroid therapy for at least one month and who had undergone six LDL-A procedures. The effects of steroids and LDL-A on the production of IL-8, TNF-alpha, and MCP-1 by peripheral blood mononuclear cells (PBMCs) were also determined in some patients.. In NS, the serum levels of IL-8 and TNF-alpha, but not MCP-1, were significantly higher than in healthy controls. After LDL-A, IL-8 and TNF-alpha tended to decrease. IL-8 production by lipopolysaccharide (LPS)-stimulated PBMC, mainly adherent cells, was significantly reduced in both the steroid-resistant FGS group and nontreated NS group compared with controls, but TNF-alpha production was reduced in the only FGS group. After LDL-A, only IL-8 production recovered to the control group level.. Significant amelioration of IL-8 production independent of any effect of steroids on LPS-stimulated PBMCs may reflect a beneficial effect of LDL-A in normalizing the function of circulating monocytes in steroid-resistant FGS.

Topics: Blood Component Removal; Chemokine CCL2; Drug Resistance; Female; Glomerulonephritis, Membranous; Glomerulosclerosis, Focal Segmental; Humans; Interleukin-8; Leukocytes, Mononuclear; Lipoproteins, LDL; Male; Nephrotic Syndrome; Steroids; Tumor Necrosis Factor-alpha

Glucocorticosteroid (GC) is one of the most effective drugs available for the treatment of primary nephrotic syndrome (PNS) in children. However, some patients show little or no response to GC. The purpose of our research was to observe and describe the different levels of histone deacetylase-2 (HDAC2) expression in peripheral blood lymphocytes in children with PNS compared with various responses to the GC treatment, with the primary aim to assess the correlation between HDAC2 and GC resistance in PNS children.. Forty-eight patients with PNS suffering from their first attack prior to GC treatment were chosen as subjects. They were divided into two groups, those who had steroid-sensitive nephrotic syndrome (SSNS; n = 25) and those with steroid-resistant NS (SRNS; n = 23), according to their response to a 6-week course of oral prednisone. Twenty healthy children from the Physical Examination Center in the hospital served as the control group; Peripheral blood was collected at different time points prior to GC treatment and after regular therapy. RT-PCR, western blot, and enzyme-linked immunosorbent assay (ELISA) techniques were adopted to analyze HDAC2 mRNA, protein expression, and activity, respectively, in peripheral blood lymphocytes. The level of interleukin-8 (IL-8) in serum was measured by an ELISA.. Prior to GC treatment, HDAC2 expression level and activity were lower in the SRNS group than in the SSNS and control group. A statistically significant difference in HDAC2 expression and activity were observed after GC treatment between these groups, with HDAC2 expression and activity lower in the SRNS group than in the SSNS and control groups. In the SSNS group, the expression and activity of HDAC2 were higher following GC treatment than prior to GC treatment. There was a clear difference in HDAC2 expression and activity of SRNS at the different time points. No statistically significant difference was found between the two groups. The pre-treatment and post-treatment serum IL-8 levels in the SRNS group were significantly higher than those in the SSNS group. HDAC2 from children with PNS before GC treatment and after regular therapy for 6 weeks was negatively correlated with serum IL-8 level.. The GC effect was influenced by the HDAC2 expression and activity, leading to decreased serum IL-8 levels in children with PNS. HDAC2 seems to be one of the markers of GC resistance in children with PNS.

Topics: Biomarkers; Child; Female; Glucocorticoids; Histone Deacetylase 2; Humans; Interleukin-8; Male; Nephrotic Syndrome; Prednisolone

The cytokines associated with idiopathic steroid-sensitive nephrotic syndrome (ISSNS) have not been identified definitively, because previous studies had variable sampling and population heterogeneity. To clarify the cytokines involved, serum cytokine levels were measured using uniform sampling in a homogeneous population.. Five children meeting the following criteria were included: (i) ISSNS; (ii) selectivity index <0.1; (iii) paired sera obtained in the nephrotic phase before steroid treatment (STx; group A) and in the remission phase under STx (group B); (iv) no infection; and (v) no immunosuppressant. Control groups were as follows: group C, four children with ISSNS in the remission phase without STx; group D, five with normal urinalysis; group E, five with symptomatic secondary nephrotic syndrome before STx. Cytokine levels were measured using bead-based assay.. Serum macrophage inflammatory protein-1beta (MIP-1beta) levels were higher in group B compared to group A, and group C was lower than groups A and B. Serum interleukin-8 (IL-8) levels were higher in group A than in groups B and C, and groups B and C did not differ. With regard to both cytokine levels, there were no differences between groups C and D, and groups A and E.. Serum MIP-1beta and IL-8 are associated with the clinical status of ISSNS in children. A relationship between MIP-1beta and ISSNS has not been previously reported. The mechanism by which MIP-1beta and IL-8 affect ISSNS is unclear. Nevertheless, the present findings are an interesting starting point for further investigations into the pathophysiology of ISSNS in children.

Topics: Adolescent; Chemokine CCL4; Child; Child, Preschool; Female; Glucocorticoids; Humans; Interleukin-8; Male; Nephrotic Syndrome; Th1 Cells; Th2 Cells

The pathogenesis of idiopathic nephrotic syndrome (INS) remains unknown. Several findings suggest a role for the immune system. This study aimed to evaluate immune mediators in INS by measuring plasma and urinary levels of transforming growth factor beta1 (TGF-beta1), monocyte chemoattractant protein-1 (MCP-1/CCL2), regulated on activation normal T-cell expressed and secreted (RANTES/CCL5) and IL-8 (IL-8/CXCL8) in pediatric patients with INS and in age-matched healthy controls. Patients were divided according to their response to corticosteroids: steroid-sensitive (SS, n = 8), or steroid-resistant (SR, n = 24). Immune mediators were also compared in regard with disease activity (relapse and remission). Immune mediators were measured by ELISA. Plasma TGF-beta1 levels in SR patients were approximately 2.8-fold higher than control values (p < 0.05). Urinary IL-8/CXCL8 was 2.9-fold higher in INS patients in relapse (proteinuria >100 mg/m2/24 h) when compared with patients in remission (p < 0.05), and levels had a positive correlation with individual proteinuria values (p < 0.05). Urinary IL-8/CXCL8 was significantly higher in relapsed SR than in SS patients in remission. No changes in MCP-1/CCL2 and RANTES/CCL5 levels were detected. Our findings suggest that IL-8/CXCL8 and TGF-beta1 are involved in the pathogenesis of INS: IL-8/CXCL8 associated with local changes in glomerular permeability and TGF-beta1 could be related to worse response to corticosteroids.

Topics: Adolescent; Chemokine CCL2; Chemokine CCL5; Child; Female; Humans; Immunologic Factors; Interleukin-8; Male; Nephrotic Syndrome; Proteinuria; Transforming Growth Factor beta1

To investigate the path of viral transactivation of transcription by nuclear factor-kappa B (NF-kappaB) in the pathogenesis of steroid-responsive simple nephrotic syndrome (SRSNS) triggered by respiratory tract viruses.. Children with SRSNS (including active stage, convalescent and remissive stage) were examined and were analytically compared to children with nephritic nephrosis, secondary glomerular diseases and bronchiolitis; healthy children were enrolled as controls. The methods of electrophoretic mobility shift assay (EMSA), of reverse transcription-PCR (RT-PCR), and of enzyme-linked immunosorbent assay (ELISA), were used to detect the transcriptive activity of NF-kappaB, the gene expression of respiratory tract viruses (respiratory syncytial virus-RSV, influenza virus-Flu) in peripheral blood mononuclear cells (PBMC), and the levels of IL-8 and viral antibodyies in serum, respectively.. (1) Compared with the control and SRSNS in convalescent and remissive stage, the activity of NF-kappaB in PBMC of SRSNS in active stage was statistically elevated (P<0.05). (2)The level of IL-8 in serum of SRSNS in active stage was significantly increased, compared with healthy control (P<0.001). There was a positive linear correlation between the activity of NF-kappaB and the level of IL-8 in active stage of SRSNS, and a positive correlation trend was observed between the activity of NF-kappaB and the gene expression of respiratory tract viruses.. Viral transactivation of transcription by NF-kappaB may be an important path for respiratory tract viruses triggering the pathogensis of SRSNS.

Topics: Child; Child, Preschool; Female; Humans; Infant; Interleukin-8; Male; Nephrotic Syndrome; NF-kappa B; Orthomyxoviridae; Respiratory Syncytial Viruses; Transcription, Genetic

Interleukin-13 (IL-13) is a known modulator of monocyte function, down-regulating monocyte surface markers such as CD14 and proinflammatory cytokines. We have shown previously that lymphocyte IL-13 gene expression was up-regulated during relapses in children with steroid-responsive nephrotic syndrome (SRNS). In this study, we examined the monocyte mRNA expression and lipopolysaccharide (LPS)-stimulated intracellular production of tumour necrosis factor-alpha (TNF-alpha) and IL-8 in children with SRNS during relapse and remission. Additionally, we investigated CD14 mRNA levels, CD14 surface expression and its soluble component (sCD14) in serum. Our results showed that the percentages of TNF-alpha positive monocytes following LPS stimulation were significantly lower in nephrotic children in relapse (64.4 +/- 13.7%) compared to remission (81.6 +/- 9.0%, P < 0.005). This was associated with down-regulation of CD14 mRNA, as well as both membrane and sCD14 in patients with nephrotic relapse (82.9 +/- 10.1% and 1.23 +/- 0.30 micro g/ml, respectively) compared to remission (93.9 +/- 3.2% and 1.77 +/- 0.82 micro g/ml, respectively) (P < 0.003). Although we demonstrated a decrease in LPS-stimulated intracellular production of TNF-alpha in monocytes from patients with nephrotic relapse, we were unable to show a concomitant decrease in mRNA expression during relapses. This could be explained by down-regulation of gene expression at the translational rather than transcriptional level. In conclusion, it is conceivable that up-regulation of T-cell IL-13 production in children with active nephrotic relapse was associated with suppression of monocyte CD14 expression, down-regulating pro-inflammatory cytokine production, and could account for the increased susceptibility to bacterial sepsis seen in nephrotic children in active relapse.

Topics: Adolescent; Adult; Case-Control Studies; Cell Membrane; Cells, Cultured; Child; Child, Preschool; Cross-Sectional Studies; Female; Glucocorticoids; Humans; Interleukin-13; Interleukin-8; Lipopolysaccharide Receptors; Lipopolysaccharides; Male; Monocytes; Nephrotic Syndrome; Recurrence; RNA, Messenger; Tumor Necrosis Factor-alpha

The pathogenesis of childhood nephrotic syndrome (NS), whether the lesion is minimal change disease (MCD) or focal segmental glomerulosclerosis (FSGS), remains elusive. Based on the presence of elevated cytokine levels in peripheral blood, a T cell-induced injury could be postulated.. To test the hypothesis that infiltrating T cells actively contribute to the glomerular injury in children with NS, we studied the intrarenal transcription of various T cell-related chemokines, cytokines and cytotoxic T-lymphocyte (CTL) effector molecules in the renal biopsy tissue of 52 nephrotic children with a variety of histologic lesions. Intrarenal gene expression was studied using reverse transcription (RT)-assisted-polymerase chain reaction (PCR).. Interleukin-2 (IL-2) and IL-4 transcripts were not observed in any of the specimens. IL-2 receptor alpha mRNA was detected in 24 of 40 proteinuric patients, but also in 6 of 10 patients in remission and showed no significant differences with regard to steroid response. Intrarenal gene expression of CTL mediators and transforming growth factor-beta1 (TGF-beta1) was noted particularly in patients with progressive disease leading to chronic renal failure. TGF-beta1 gene expression was noted in 23 of 29 steroid resistant (SR) children with NS not caused by lupus nephritis and in 18 of 20 FSGS patients. In contrast TGF-beta1 gene expression was detected in only 3 of 14 steroid-sensitive patients (P < 0.001). Two of these patients later developed FSGS. In patients with steroid-resistant NS, intrarenal TGF-beta1 gene expression showed a positive predictive value of 90% and a negative predictive value of 88% to identify FSGS (P < 0.0001).. These results support the notion that immunologically mediated events contribute to the progressive renal damage seen in children with FSGS.

Topics: Biopsy; Chemokine CCL5; Child; Glomerulosclerosis, Focal Segmental; Humans; Interleukin-15; Interleukin-17; Interleukin-2; Interleukin-2 Receptor alpha Subunit; Interleukin-4; Interleukin-7; Interleukin-8; Kidney; Nephrotic Syndrome; Polymerase Chain Reaction; Receptors, Interleukin; T-Lymphocytes, Cytotoxic; Transcription, Genetic; Transforming Growth Factor beta; Transforming Growth Factor beta1

We investigated the production of cytokines by peripheral blood mononuclear cells (PBMC) and serum cytokine concentrations in children with steroid-sensitive idiopathic nephrotic syndrome (SSNS). PBMC from patients off treatment were collected during remission and relapse and cultured in medium alone or stimulated with calcium ionophore plus phorbol myristate acetate. Control PBMC were taken from healthy age-matched children. IL-2 was measured by bioassay, IL-4 by immunoradiometric assay, and IL-8 and IFN-gamma by ELISA. After 24 h culture without stimulation, IL-2, IL-4 and IFN-gamma were not detectable in the supernatant in any of the children. After stimulation, the supernatant concentrations of IL-2 (median 172 U/ml at 24 h) and IL-4 (160 pg/ml at 24 h; 210 pg/ml at 72 h) were significantly increased in relapse compared with remission (IL-2 37 U/ml; IL-4 65 pg/ml and 60 pg/ml) and controls (IL-2 69 U/ml; IL-4 40 pg/ml and 40 pg/ml) (P < 0.05). The concentration of IFN-gamma was not significantly increased in relapse compared with remission and controls (600, 325, and 145 U/ml, respectively, at 72 h). IL-8 concentrations were similar in relapse, remission and controls with stimulation (median 32, 40 and 40 ng/ml, respectively) and without (30, 17 and 10 ng/ml). IL-2 was not detectable in serum, but IL-4, IL-8 and IFN-gamma were measurable in about half the patients, both in relapse and remission, though were virtually undetectable in controls. We conclude that relapse of SSNS in children is associated with T lymphocyte activation with release of IL-2, IL-4 and IFN-gamma.

Topics: Adolescent; Child; Female; Humans; In Vitro Techniques; Interferon-gamma; Interleukin-2; Interleukin-4; Interleukin-8; Leukocytes, Mononuclear; Lymphocyte Activation; Male; Nephrotic Syndrome