Elevated plasma TGF-beta1 in renal diseases: cause or consequence?

Downregulation of the endothelial histone demethylase JMJD3 is associated with neointimal hyperplasia of arteriovenous fistulas in kidney failure

Jumonji domain-containing protein-3 (JMJD3), a histone H3 lysine 27 (H3K27) demethylase, promotes endothelial regeneration, but its function in neointimal hyperplasia (NIH) of arteriovenous fistulas (AVFs) has not been explored. In this study, we examined the contribution of endothelial JMJD3 to NIH of AVFs and the mechanisms underlying JMJD3 expression during kidney failure. We found that endothelial JMJD3 expression was negatively associated with NIH of AVFs in patients with kidney failure. JMJD3 expression in endothelial cells (ECs) was also downregulated in the vasculature of chronic kidney disease (CKD) mice. In addition, specific knockout of endothelial JMJD3 delayed EC regeneration, enhanced endothelial mesenchymal transition, impaired endothelial barrier function as determined by increased Evans blue staining and inflammatory cell infiltration, and accelerated neointima formation in AVFs created by venous end to arterial side anastomosis in CKD mice. Mechanistically, JMJD3 expression was downregulated via binding of transforming growth factor beta 1-mediated Hes family transcription factor Hes1 to its gene promoter. Knockdown of JMJD3 enhanced H3K27 methylation, thereby inhibiting transcriptional activity at promoters of EC markers and reducing migration and proliferation of ECs. Furthermore, knockdown of endothelial JMJD3 decreased endothelial nitric oxide synthase expression and nitric oxide production, leading to the proliferation of vascular smooth muscle cells. In conclusion, we demonstrate that decreased expression of endothelial JMJD3 impairs EC regeneration and function and accelerates neointima formation in AVFs. We propose increasing the expression of endothelial JMJD3 could represent a new strategy for preventing endothelial dysfunction, attenuating NIH, and improving AVF patency in patients with kidney disease.

Evaluating the Serum Transforming Growth Factor-Beta 1 Level in Chronic Kidney Disease Caused by Glomerulonephritis

Background: The transforming growth factor-beta 1 (TGF-β1) has been demonstrated as one of the main factors in the progression of fibrosis and sclerosis glomerular damages. Glomerulonephritis is one common cause of chronic kidney disease (CKD) with the promotion of inflammatory renal damage containing fibrosis and sclerosis glomerular. Objectives: This study aimed to evaluate the TGF-β1 level in CKD patients and compare it with the healthy control group. Methods: This cross-sectional case-control study was carried out on 212 subjects admitted to the Nghe An Friendship General Hospital in Vietnam from March 2018 to February 2020. The case group included 152 patients diagnosed with CKD caused by glomerulonephritis, and the control group included 60 healthy individuals. The TGF-β1 was determined in serum by ELISA method. Results: The serum TGF-β1 concentration of the healthy control group and CKD group was 13.45 ± 7.17 and 32.35 ± 11.74, respectively. The CKD group had a significantly higher TGF-β1 level than the control group (P < 0.05). The CKD group with the eGRP ≥ 60 mL/min/1.73 m2 group had a higher TGF-β1 level than the eGRP < 60 mL/min/1.73 m2 group, and the TGF-β1 level increased from stage 1 to stage 5 (P < 0.001). The TGF-β1 had a medium correlation to urea, creatinine, and hs-CRP. Conclusions: The concentration of TGF-β1 in the CKD group was higher than the control group so that it increased early from the first stage of the disease.

Can Tumor Necrosis Factor- α and Interleukin-6 Be Used as Prognostic Markers of Infection following Ureteroscopic Lithotripsy?

Introduction. Ureteroscopic lithotripsy (URS) although highly effective for the treatment of ureteral stones is associated with certain complications, the more common of which are postoperative fever and infection. In the present study we aimed to evaluate the levels of serum cytokines in patients undergoing ureteroscopic lithotripsy and investigate any possible correlation between levels of cytokines and infectious complications after URS. Materials and Methods. Thirty patients (19 males, 11 females), with a mean age of 47 (range: 26-68) that underwent URS lithotripsy for ureteral stones, and 10 healthy volunteers serving as the control group were enrolled in this study. Serum samples for TNF- α and IL-6 were obtained before surgical intervention and after 1, 24, and 48 hours and 2 , 24, and 48 hours, respectively. The preoperative and postoperative levels were compared and correlated with the possible complications after URS. Results. Serum TNF- α levels were statistically significant, increased 1 hour (P = 0.0083) and 48 hours (P < 0.001) after operation. IL-6 levels were found statistically significant, elevated after 2 and 24 hours from the URS (P < 0.001). In 2 patients we observed postoperative fever (>38.5°C). These two patients had high preoperative values of TNF- α and IL-6 ( 30 and 50 pg/mL, resp.) and these values increased postoperatively. Conclusion. High preoperative levels of serum TNF- α and IL-6 may indicate a predisposition for postoperative inflammation and infection following URS lithotripsy.

Evaluation of TGF-β1, CCL5/RANTES and sFas/Apo-1 urine concentration in children with ureteropelvic junction obstruction

INTRODUCTION

The aim of this study was to evaluate changes in expression of soluble biomarkers tumor factor growth-β1 (TGF-β1), CCL5/RANTES, and sFas/Apo-1 in the urine of patients undergoing ureteropyeloplasty for ureteropelvic junction (UPJ) obstruction. These factors are connected with different processes ongoing in the obstructive uropathy. If their urine concentrations correlate with AP diameter of the renal pelvis and differential function of the affected kidney, they can be helpful in making a decision on corrective surgery.

MATERIAL AND METHODS

Creatinine, TGF-β1, CCL5/RANTES, and sFas/Apo-1 levels were measured in the urine from the bladder and renal pelvis of 45 patients undergoing ureteropyeloplasty and from bladders of 25 patients undergoing inguinal herniorrhaphy.

RESULTS

LEVELS OF EXAMINED BIOMARKERS WERE HIGHER IN THE RENAL PELVIS AND BLADDER OF CHILDREN WITH UPJ OBSTRUCTION AS COMPARED TO CONTROLS: TGF-β1 in older children and adolescents (p < 0.05), CCL5/RANTES in the youngest and older children (p < 0.05), and sFas/Apo-1 in all patients (p < 0.05). Twelve months after surgery their levels in the bladder decreased: TGF-β1 in younger and older children (p < 0.05), CCL5/RANTES in the youngest patients and adolescents (p < 0.05), and sFas/Apo-1 in the youngest and older children (p < 0.05). A significant decrease in the AP diameter of the renal pelvis post-operatively (32.09 mm vs. 18.72 mm) (p < 0.01) and significant improvement in renal function (36.94% vs. 42.76%) (p < 0.05) were observed in the examined group.

CONCLUSIONS

Mean TGF-β1, CCL5/RANTES, and sFas/Apo-1 urine levels are significantly increased in patients with UPJ and decreased 1 year after ureteropyeloplasty. Bladder concentrations of examined factors may be clinically useful markers of obstruction.

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.

Transforming growth factor-β downregulates interleukin-2-induced phosphorylation of signal transducer and activator of transcription 5 in human renal cell carcinoma

PURPOSE

We investigated signal transducer and activator of transcription-5 (STAT5) activation status in renal cell carcinoma (RCC) and the role of transforming growth factor-beta (TGF-beta) in the process.

METHODS

Twenty normal and RCC tissues were obtained from radical nephrectomy specimens for the assessment of expressions of phosphorylated STAT5 (p-STAT5) and TGF-beta1 (Western blot) and for localization and assessment of their relationship (immunohistochemical and immunofluorescence stains). By using four RCC cell lines and four primary cultured cells, the effect of TGF-beta1 and/or interleukin-2 (IL-2) on the expressions of p-STAT5 were analyzed.

RESULTS

In RCC samples, expression of p-STAT5 was significantly reduced while expression of TGF-beta was enhanced compared with normal kidney tissues (P < 0.001 and P = 0.003, respectively). P-STAT5 was observed almost exclusively in the nuclei of normal kidney tissues while TGF-beta was identified in the cytoplasm of cells of both tissues reflecting the Western results. In both RCC cell lines and cells from primary cultures, treatment with TGF-beta or antibody did not significantly alter STAT5 activation. However, TGF-beta significantly suppressed IL-2-induced STAT5 activation, whereas anti-TGF-beta antibodies enhanced IL-2-induced STAT5 further.

CONCLUSIONS

STAT5 activation is suppressed in RCC compared with normal renal parenchyma. It may be attributed to the RCC-derived TGF-beta which also interferes with IL-2-induced STAT5 pathway activation.

Systemic mediators induce fibrogenic effects in normal liver after partial bile duct ligation

BACKGROUND/AIMS

Collagen production by activated hepatic stellate cells (HSCs) is a key event in liver fibrosis, and a number of factors have been characterized that trigger HSC activation and collagen production. However, it remains unclear if these factors act locally at the site of injury or also affect HSCs distant to the site of injury.

METHODS

A model of partial bile duct ligation (PBDL) in which fibrogenesis can be compared between the injured ligated lobe and the non-ligated lobe.

RESULTS

After PBDL, HSCs showed an increased expression of procollagen type I alpha1 mRNA and collagen-reporter gene activity not only in the ligated lobe, but also in the non-ligated lobe, albeit at a lower level. In contrast, an increase in the number of desmin- and alpha-smooth muscle actin positive HSCs, and accumulation of inflammatory cells were observed only in the ligated lobe. Although transforming growth factor-beta (TGF-beta) mRNA was increased only in the ligated lobe, Smad2/3 were activated in the ligated and the non-ligated lobe. These data suggest that the systemic increase in profibrogenic mediators including TGF-beta induces collagen transcription in the uninjured liver.

CONCLUSION

Systemic profibrogenic mediators from the injury site affect the residual non-injured liver.

Molecular pathogenetics of renal cancer

Recent developments in genetics and molecular biology have led to an increased understanding of the pathobiology of renal cancer. Thorough knowledge of the molecular pathways associated with renal cancer is a prerequisite for novel potential therapeutic interventions. Studies are ongoing to evaluate novel anticancer agents that target specific molecular entities. This article reviews current knowledge on the genetics and molecular pathogenesis of sporadic and inherited forms of renal cancer.

Profibrotic cytokines and lymphocyte proliferation in stable renal allograft recipients treated with or without cyclosporine A

Profibrotic cytokines such as transforming growth factor-beta 1 (TGF-beta1) and endothelin-1 (ET-1) are involved in the pathogenesis of chronic allograft nephropathy. We assessed the effect of maintenance immunosuppression with or without cyclosporine A on TGF-beta1 and ET-1 expression as well as lymphocyte proliferation in renal allograft recipients. Patients were divided into groups according to their maintenance immunosuppression: A, azathioprine + methylprednisolone; B, cyclosporine A + azathioprine + methylprednisolone. TGF-beta1 and ET-1 plasma concentrations were not different between both groups. TGF-beta1 concentrations in cell culture supernatants and lymphocyte proliferation were higher in group B as compared to group A. No correlation was found between TGF-beta1 plasma concentrations and lymphocyte proliferation. Multiple linear regression analysis revealed that patient characteristics influence TGF-beta1 and ET-1 expression. In conclusion, plasma levels of profibrotic cytokines do not reflect the existing profibrotic potential of immunosuppressive drugs. Demographic factors and the employed co-medication confound the results.

Bone and bone marrow interactions: hematological activity of osteoblastic growth peptide (OGP)-derived carboxy-terminal pentapeptide

The increase of megakaryocytes and platelets that characterizes essential thrombocythemia (ET) appears to be secondary to a deregulation of megakaryocytopoiesis. The carboxy-terminal fragment of osteogenic growth peptide (OGP10-14) promotes bone formation and hemopoiesis, while it inhibits megakaryocytopoiesis. In this paper we show that treatment with synthetic OGP10-14 (sOGP10-14) induces a significant reduction of mid and large colony-forming unit-megakaryocytes (CFU-Mk) in ET patients as well as in controls, and is associated with a significant inhibition of thrombopoietin (TPO)-primed MO-7e megakaryoblastic cells proliferation. These actions appear to be related to sOGP10-14 modulation of TGF-beta(1) synthesis and/or secretion, although a direct effect on TGF-beta receptor expression cannot be excluded.

Expression of transforming growth factor beta in renal cell carcinoma and matched non-involved renal tissue

TGFbeta1 is one of several cytokines produced by proximal tubular and renal cancer cells. Previous studies have been mainly focused on determining plasma or serum TGFbeta levels, its effect on RCC cultures, and the expression of TGFbeta mRNA. Cancerous and autologous normal kidney samples were obtained from 24 patients treated by radical nephrectomy. TGFbeta1 expression was determined using a semi quantitative Western blot analysis and immunohistochemistry. Blot densities and immunohistochemical expression intensities in normal and neoplastic tissue were compared, and subsequently correlated to tumor stage, histological type and nuclear grade. All tissue samples examined expressed TGFbeta1; mean tumor to non-involved kidney spot density ratio correlated with advancing stage and higher nuclear grade. The overexpression of TGFbeta1 in certain RCCs may partially explain their resistance to the growth suppression action of TGFbeta. The correlation with tumor stage and grade indicates a possible role in the development of metastatic potential as well as in host's immune response modulation.

Nephrogenic fibrosing dermopathy: an unusual skin condition associated with kidney disease

We report the case of a patient who, while on long-term hemodialysis (HD), developed nephrogenic fibrosing dermopathy, a newly described sclerosing skin disorder. This disorder is characterized by thickened, hardened skin with brawny hyperpigmentation and raised plaques. The most common patient complaints are pruritus and dysesthesia. The extremities are predominantly involved with sparing of the torso and face. Dysfunction of internal organs has not been described, distinguishing it from other fibrosing conditions such as scleroderma. The skin biopsy is characterized by haphazardly arranged dermal collagen spindle cells in the reticular dermis. Extensive mucin deposits are interposed between collagen bundles and there are an increased number of fibroblast-type cells. In contrast to scleroderma, inflammatory cells are generally absent. Corticosteroid therapy can be tried, but in our patient was of no benefit.

Circulating angiogenic growth factor levels in mice bearing human tumors using Luminex Multiplex technology

Tumor angiogenesis is essential for tumor growth and metastasis formation. Luminex methodology was used to measure the levels of four angiogenic cytokines in cell culture medium and in the plasma of mice bearing human tumors. We obtained plasma and conditioned culture medium from 12 different human tumor cell lines. Tumor necrosis factor-alpha (TNF-alpha), basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), and transforming growth factor-beta (TGF-beta) were determined by the Luminex FlowMetrix assay. VEGF, TNF-alpha, and bFGF were undetectable in non-tumor-bearing animals. HS746T gastric cancer and Caki-1 renal cell cancer cells in culture produced high levels of VEGF (1000 and 450 pg/10(6) cells, respectively). High levels of TGF-beta were produced by HS746T gastric carcinoma and Calu-6 non-small-cell lung carcinoma (3000 and 1000 pg/10(6) cells, respectively). Caki-1 renal cell carcinoma and Calu-6 non-small-cell lung carcinoma cells in culture produced high levels of bFGF (42 and 10 pg/10(6) cells, respectively). Caki-1, SW2 SCLC, HCT-116 and HT-29 colon tumors produced high plasma levels of VEGF (200, 220, 42, and 151 pg/ml, respectively) and TGF-beta (31, 36, 45, 32 pg/ml, respectively). A positive linear correlation was seen between tumor volume and VEGF in SW2 (r=0.87) and Caki-1 (r=0.47) tumors, and a moderate correlation in HCT116 tumors (r=0.3). Angiogenic profiles in the plasma of nude mice bearing human tumors may be useful to identify appropriate biomarkers for antiangiogenic therapy, as diagnostic and prognostic tools, and to monitor the responses of individual tumors to antiangiogenic therapy.

Carboxy-terminal fragment of osteogenic growth peptide in vitro increases bone marrow cell density in idiopathic myelofibrosis

Idiopathic myelofibrosis (IMF) is a clonal stem cell disorder characterized by reactive fibrosis of bone marrow sustained by a complex cytokine network. At present, no efficacious therapy for this disease exists. Synthetic carboxy-terminal pentapeptide of osteogenic growth factor (sOGP10-14) can increase bone marrow cellularity and the number of haematopoietic colonies; this study evaluated the activity of sOGP10-14 in IMF. Fragments of bone marrow biopsies from patients affected by IMF were cultured with or without the addition of sOGP10-14. Cellular density was evaluated by image analysis, and transforming growth factor-beta1 (TGF-beta1) concentration was immunologically assayed in the supernatant of cultured bone marrow biopsies. The proliferation rate of the megakaryoblastic M07-e cell line, cultured in the presence of either granulocyte-macrophage colony stimulating factor or thrombopoietin (TPO), and with or without sOGP10-14, was evaluated. Megakaryocyte colony forming unit (CFU-Mk) assay was performed on bone marrow samples of IMF patients with or without sOGP10-14. After 14 d, bone marrow cellularity was significantly increased in samples cultured with the pentapeptide. Moreover, sOGP10-14 induced a significant increase of TGF-beta in culture supernatants. TPO-primed proliferation of M07-e was reduced by sOGP10-14, and the pentapeptide significantly reduced CFU-Mk on IMF bone-marrow-derived cells. sOGP10-14 increased ex vivo bone marrow cellularity in IMF. This action could be related to the megakaryocyte inhibition induced by the interference of this pentapeptide with growth factor activities. These findings suggest that a deficiency of osteoblast-related factors may play a role in bone marrow failure in IMF.

Cadmium- and mercury-induced intercellular adhesion molecule-1 expression in immortalized proximal tubule cells: evidence for a role of decreased transforming growth factor-beta1

A definitive association between the aberrant expression of cytokines and adhesion molecules in renal failure has been established. In this regard a relationship between cytokine and adhesion molecule expression is suggested but has not been shown in models of proximal tubular cell injury. To investigate the impact of acute injury on the relationship between transforming growth factor-beta 1 (TGF-beta1) and intercellular adhesion molecule-1 (ICAM-1) expression, two immortalized mouse proximal tubular epithelial cell lines were exposed to cadmium chloride or mercuric chloride (0-50 microM) for 0-8 h. ELISA and Western blot measured expression of secreted and intercellular TGF-beta1, respectively. Direct cellular ELISA or Western blot was used to assess ICAM-1 expression. Challenge with cadmium caused a greater loss of cell viability than did mercury. Interestingly, cadmium significantly decreased the amount of TGF-beta1 in the conditioned media. Although a similar trend was seen in mercury-challenged cells, no significant differences were observed. The decrease in TGF-beta1 in the culture media was not due to decreased expression of this cytokine, as intercellular levels were not affected by metal-induced injury. Significant increases in ICAM-1 protein expression were observed following cadmium and mercury challenge. The increase in ICAM-1 appears to be due to increased mRNA, as Northern blot analysis demonstrated increased message expression following a 4-h cadmium or mercury challenge. Supplementation of the culture media with exogenous TGF-beta1 decreased basal ICAM-1 expression and attenuated the cadmium-induced increase. These data suggest that metal-induced injury is associated with increased ICAM-1 expression. The mechanism of this induction may involve the decreased TGF-beta1 in the conditioned media following metal challenge. Taken together, these studies suggest a link between cytokine and adhesion molecule expression in renal injury.

Novel therapies for renal cell carcinoma

Metastatic renal cell cancer remains a disease which is difficult to treat medically. Prognosis often depends more on intrinsic disease features than on treatment choices. In this review, we examine novel therapies and scientific directions surrounding the RCC treatment problem. Reports relating chromosomal aberrations and of comparative gene expression analyses relating to RCC, are reviewed briefly. The central role of the von Hippel Lindau protein in clear cell RCC pathogenesis is evident. The limited contribution of conventional cytotoxic chemotherapy is mentioned. Some clinically applied agents whose clinical results are highlighted include 5-FU, retinoids, thalidomide, razoxane and IL-12. Features of the pathophysiology of von Hippel Lindau protein are described, with attention to potential novel therapies targeting HIF-1alpha, VEGF, TGF-beta1 and TGF-alpha pathways. Immunotherapy is being explored in many angles. Most basic are cytokine therapies incorporating new IL-2 and IFN-alpha schedules. Newer cytokine-based drugs include pegylated forms and IL-12. Allogeneic mini-transplantation has generated much interest. Tumour-associated antigens are being used to direct therapy using both identified and non-identified epitopes. A variety of tumour-cell vaccine and dendritic-cell vaccine clinical approaches are discussed. Finally, nephrectomy for known metastatic disease has been demonstrated to be helpful in retrospective and now prospective trials. Resection of metastases is also discussed. We are optimistic that the further clinical development among these novel therapies will improve the outlook for metastatic RCC.