Deletion of bradykinin B1 receptor reduces renal fibrosis

doi:10.1016/j.intimp.2008.10.018

International Immunopharmacology

Volume 9, Issue 6, June 2009, Pages 653-657

https://doi.org/10.1016/j.intimp.2008.10.018 Get rights and content

Abstract

The Kallikrein–kinin system works through activation of two receptors. One constitutive, named B2 receptor (B2R) and another inducible, denominated B1 receptor (B1R). In renal fibrosis, B2R receptor activation appears to be protective, however B1R participation is unveiled. The aim of this study was to analyze how the deletion of the B1R would modify tissue responses after unilateral ureteral obstruction (UUO). For that, B1R knockout (B1KO) and wild-type mice (B1B2WT) were subjected to UUO and sacrificed at days 1, 5 and 14. Renal dysfunction was assayed by urine proteinuria/creatinine ratio and percentage of tubulointerstitial fibrosis. Kidneys were harvested at day 5 to analyze anti and pro-inflammatory molecules expression by real-time PCR. We demonstrated that at all time points, B1KO mice presented lower proteinuria/creatinine ratio from bladder urine. B1KO protection was reinforced by its lower tubular interstitial fibrosis percentage at day 14 (B1B2WT: 12.16 ± 1.53% vs. B1KO: 6.73 ± 1.07%, p < 0.02). UUO was able to induce B1R expression and its highest transcription was achieved at day 5. At this day, B1KO had significant lower expression of pro-inflammatory molecules such as TGF-β, MCP-1, OPN and IL-6 and higher anti-inflammatory components, as IL-10 and HO-1. Herein, we observed that B1R deletion may be an important component in renal fibrosis prevention.

Introduction

Renal fibrosis is a process typically resulted from chronic inflammation, in a mechanism involving production of several molecules, such as growth factors, proteolytic enzymes, angiogenic factors and fibrogenic cytokines. All of them can stimulate the deposition of connective tissue components that progressively remodel and destroy normal tissue architecture [1], [2], [3]. The unilateral ureteral obstruction (UUO) includes many aspects of different kidney diseases and is a classic model used to study renal fibrosis [4], [5], [6]. In UUO, complete obstruction of urether leads to macrophage infiltration, epithelial–mesenchymal transition (EMT) of tubular cells, activated myofibroblasts accumulation and extracellular matrix (ECM) enhancement that ultimately culminate in tubular atrophy, interstitial fibrosis and permanent loss in renal function [7].

The use of Renin–angiotensin system inhibitors was shown to reduce fibrosis in experimental hydronephrosis [8], [9], [10]. We emphasize that ACE inhibitors have a side-effect in the Kallikrein–kinin system due to a dual inhibition of bradykinin degradation [11]. Therefore, a relationship between the Kallikrein–kinin system and tubulointerstitial fibrosis may exist [12].

The Kallikrein–kinin system acts through two transmembrane receptors, one constitutively expressed named B2 (B2R) and the other inducible under inflammatory signals [13] or by Des-Arg⁹-BK [14], denominated B1 (B1R). In UUO, bradykinin overexpression reduced tubulointerstitial fibrosis and in vivo B2R deletion was deleterious [15]. Thus, it is believed that bradykinin may be anti-fibrotic via B2R activation. Surprisingly, little is known about B1R participation in this process. Thus, this study aimed to evaluate B1R expression and influence in immune mechanisms throughout UUO. Herein, we observed that B1R is activated by UUO and its higher expression was found 5 days after the insult. Even more, B1R deletion resulted in less pro-inflammatory TGF-β, MCP-1, OPN and IL-6 and higher anti-inflammatory HO-1 and IL-10 expression.

Section snippets

Animals

Isogenic male B1R-deficient C57BL/6 mice, age 8–12 weeks (25–28 g), were kindly donated by Prof. João Bosco Pesquero of Biophysics Department of Federal University of São Paulo (UNIFESP), Brazil. All animals were housed in individual and standard cages and had free access to water and food. Wild-type C57BL/6 mice, age and sex-matched, were used as control animals. All procedures were previously reviewed and approved by the internal Ethical Committee of the Institution.

Experimental model of unilateral ureteral obstruction

Mice were briefly

Bradykinin B1R expression after UUO

B1R may be important in the development of UUO and to study this hypothesis it was first necessary to observe whether this insult could trigger B1R expression. Receptor expression was analyzed in wild-type mice at days 1, 5 and 14 after UUO. At all time points, B1R expression was detected. The highest B1R transcription was observed at day 5, especially in the obstructed kidney (Fig. 1).

Deletion of B1R and the development of fibrosis

To understand whether B1R could have an impact in tissue fibrosis, we submitted B1KO mice to UUO and analyzed

Discussion

In recent years, the participation of hemodynamic factors in the development of renal fibrosis has been investigated. All major component of the Renin–angiotensin system exert pro-fibrotic activities, especially angiotensin II (AngII) which is considered the dominant hormone responsible for renal fibrosis [17], [18]. AngII can be locally produced by activated macrophages and fibroblasts. It stimulates TGF-β production and triggers fibroblast proliferation and differentiation into

References (54)

S. Klahr et al.
Angiotensin II and gene expression in the kidney
Am J Kidney Dis
(1998)
J.L. Bascands et al.
Obstructive nephropathy: insights from genetically engineered animals
Kidney Int
(2005)
E. Serlachius et al.
Protein kinase C in the developing kidney: isoform expression and effects of ceramide and PKC inhibitors
Kidney Int
(1997)
S. Ishidoya et al.
Angiotensin II receptor antagonist ameliorates renal tubulointerstitial fibrosis caused by unilateral ureteral obstruction
Kidney Int
(1995)
A. Ishikawa et al.
Prevention of interstitial fibrosis of renal allograft by angiotensin II blockade
Transplant Proc
(2006)
A. Ni et al.
Overexpression of kinin B1 receptors induces hypertensive response to des-Arg9-bradykinin and susceptibility to inflammation
J Biol Chem
(2003)
A. Dray et al.
Bradykinin and inflammatory pain
Trends Neurosci
(1993)
A. Ahluwalia et al.
Calcitonin gene-related peptides modulate the acute inflammatory response induced by interleukin-1 in the mouse
Eur J Pharmacol
(1994)
C.W. Tiffany et al.
Bradykinin stimulates tumor necrosis factor and interleukin-1 release from macrophages
FEBS Lett
(1989)
P.H. Wang et al.
Influence of bradykinin B1 and B2 receptors in the immune response triggered by renal ischemia-reperfusion injury
Int Immunopharmacol
(2006)

K. Fukuda et al.

Quantification of TGF-beta1 mRNA along rat nephron in obstructive nephropathy

Am J Physiol Renal Physiol

(2001)

F. Strutz et al.

Identification and characterization of a fibroblast marker: FSP1

J Cell Biol

(1995)

Cited by (32)

Inflammation and renal fibrosis: Recent developments on key signaling molecules as potential therapeutic targets
2018, European Journal of Pharmacology
Citation Excerpt :
Klein and colleagues observed an association between inflammation and expression of bradykinin B1 receptor (B1R) in the glomerulus and renal interstitium of patients with various forms of glomerulonephritis, including ANCA-associated vasculitis and Henoch-Schönlein purpura nephropathy (Klein et al., 2010). B1R expression is also upregulated in the UUO and nephrotoxic serum-induced models of renal injury (Klein et al., 2010, 2009; Wang et al., 2009). Treatment with a B1R antagonist, ssR240612 (Table 1), was found to block macrophage infiltration, leading to a reversal of renal fibrosis in rodent models of UUO and serum nephritis.
Chronic kidney disease (CKD) is a major public health issue. At the histological level, renal fibrosis is the final common pathway of progressive kidney disease irrespective of the initial injury. Considerable evidence now indicates that renal inflammation plays a central role in the initiation and progression of CKD. Some of the inflammatory signaling molecules involved in CKD include: monocyte chemoattractant protein-1 (MCP-1), bradykinin B₁ receptor (B₁R), nuclear factor κB (NF-κB), tumor necrosis factor-α (TNFα), transforming growth factor β (TGF-β), and platelet-derived growth factor (PDGF). Multiple antifibrotic factors, such as interleukin-10 (IL-10), interferon-γ (IFN-γ), bone morphogenetic protein-7 (BMP-7), hepatocyte growth factor (HGF) are also downregulated in CKD. Therefore, restoration of the proper balance between pro- and antifibrotic signaling pathways could serve as a guiding principle for the design of new antifibrotic strategies that simultaneously target many pathways. The purpose of this review is to summarize the existing body of knowledge regarding activation of cytokine pathways and infiltration of inflammatory cells as a starting point for developing novel antifibrotic therapies to prevent progression of CKD.
Up-regulation of the kinin B<inf>2</inf> receptor pathway modulates the TGF-β/Smad signaling cascade to reduce renal fibrosis induced by albumin
2015, Peptides
Citation Excerpt :
The role of kinin B1 receptor (B1R) was not addressed in our experiments but their potential deleterious effects deserve some commentaries since B1R is up-regulated under pathological conditions and it has been proposed as a key antifibrotic target [75]. We did not find information on the participation of B1R in vivo or in vitro during albumin loading but it has been reported that B1R blockade/deletion has a curative antifibrotic effect [76], equivalent to that obtained with valsartan, in UUO [77] and in a model of glomerulonephritis [78]. We used a high potassium diet strategy to induce kinin system activation knowing the classical relationship that has been described between potassium, adrenal aldosterone secretion and its effects on tubular kallikrein-synthesizing cells [58].
The presence of high protein levels in the glomerular filtrate plays an important role in renal fibrosis, a disorder that justifies the use of animal models of experimental proteinuria. Such models have proved useful as tools in the study of the pathogenesis of chronic, progressive renal disease. Since bradykinin and the kinin B₂ receptor (B₂R) belong to a renoprotective system with mechanisms still unclarified, we investigated its anti-fibrotic role in the in vivo rat model of overload proteinuria. Upon up-regulating the kinin system by a high potassium diet we observed reduction of tubulointerstitial fibrosis, decreased renal expression of α-smooth muscle actin (α-SMA) and vimentin, reduced Smad3 phosphorylation and increase of Smad7. These cellular and molecular effects were reversed by HOE-140, a specific B₂R antagonist.
In vitro experiments, performed on a cell line of proximal tubular epithelial cells, showed that high concentrations of albumin induced expression of mesenchymal biomarkers, in concomitance with increases in TGF-β1 mRNA and its functionally active peptide, TGF-β1. Stimulation of the tubule cells by bradykinin inhibited the albumin-induced changes, namely α-SMA and vimentin were reduced, and cytokeratin recovered together with increase in Smad7 levels and decrease in type II TGF-β1 receptor, TGF-β1 mRNA and its active fragment. The protective changes produced by bradykinin in vitro were blocked by HOE-140.
The development of stable bradykinin analogues and/or up-regulation of the B₂R signaling pathway may prove value in the management of chronic renal fibrosis in progressive proteinuric renal diseases.
The role of kinin receptors in cancer and therapeutic opportunities
2014, Cancer Letters
Citation Excerpt :
There is compelling evidence indicating that kinins are generated rapidly after tissue injury and they seem to modulate most events observed during inflammatory processes including vasodilatation, increase of vascular permeability, plasma extravasation, cell migration, pain, and also synthesis of inflammatory mediators such as eicosanoids, cytokines and nitric oxide (NO) [26]. Several lines of evidence indicate that kinins play a critical role in different inflammatory pathological states such as infections, ischemia–reperfusion injury and cancer [36,94,163,177,178]. One of the first correlations between kinins and inflammation came from the observation that the administration of BK in human or animal tissues reproduced the four cardinal signs of inflammation: redness, local heat, swelling, and pain [53].
Kinins are generated within inflammatory tissue microenvironments, where they exert diverse functions, including cell proliferation, leukocyte activation, cell migration, endothelial cell activation and nociception. These pleiotropic functions depend on signaling through two cross talking receptors, the constitutively expressed kinin receptor 2 (B2R) and the inducible kinin receptor 1 (B1R). We have reviewed evidence, which supports the concept that kinin receptors, especially kinin receptor 1, are promising targets for cancer therapy, since (1) many tumor cells express aberrantly high levels of these receptors; (2) some cancers produce kinins and use them as autocrine factors to stimulate their growth; (3) activation of kinin receptors leads to activation of macrophages, dendritic cells and other cells from the tumor microenvironment; (4) kinins have pro-angiogenic properties; (5) kinin receptors have been implicated in cancer migration, invasion and metastasis; and (6) selective antagonists for either B1R or B2R have shown anti-proliferative, anti-inflammatory, anti-angiogenic and anti-migratory properties. The multiple cross talks between kinin receptors and renin–angiotensin system (RAS) as well as its implications for targeting KKS or RAS for the treatment of malignancies are also discussed. It is expected that B1R antagonists would interfere less with housekeeping functions and therefore would be attractive compounds to treat selected types of cancer. Reliable clinical studies are needed to establish the translatability of these data to human settings and the usefulness of kinin receptor antagonists.
The kallikrein-kinin system in diabetic nephropathy
2012, Kidney International
Citation Excerpt :
Activation of B1R is associated with inflammatory response. Treatment with a B1R antagonist blocks macrophage infiltration and B1R-null mice have lower expression of pro-inflammatory molecules such as monocyte inflammatory protein 1 and interleukin-6, leading to a reduction of renal fibrosis in the unilateral ureteral obstruction model.93,94 A B1R antagonist also reduces renal inflammation and focal and segmental glomerulosclerosis induced by an adriamycin.95
Diabetic nephropathy is the major cause of end-stage renal disease worldwide. Although the renin–angiotensin system has been implicated in the pathogenesis of diabetic nephropathy, angiotensin I-converting enzyme inhibitors have a beneficial effect on diabetic nephropathy independently of their effects on blood pressure and plasma angiotensin II levels. This suggests that the kallikrein–kinin system (KKS) is also involved in the disease. To study the role of the KKS in diabetic nephropathy, mice lacking either the bradykinin B1 receptor (B1R) or the bradykinin B2 receptor (B2R) have been commonly used. However, because absence of either receptor causes enhanced expression of the other, it is difficult to determine the precise functions of each receptor. This difficulty has recently been overcome by comparing mice lacking both receptors with mice lacking each receptor. Deletion of both B1R and B2R reduces nitric oxide (NO) production and aggravates renal diabetic phenotypes, relevant to either lack of B1R or B2R, demonstrating that both B1R and B2R exert protective effects on diabetic nephropathy presumably via NO. Here, we review previous epidemiological and experimental studies, and discuss novel insights regarding the therapeutic implications of the importance of the KKS in averting diabetic nephropathy.
Bradykinin receptor 1 activation exacerbates experimental focal and segmental glomerulosclerosis
2011, Kidney International
Citation Excerpt :
In contrast, on day 4, there was no difference in interleukin-1β level among all groups (Supplementary Figure S11 online). Because B1RBK is involved in many inflammatory and fibrotic disorders,8,12,13,17,22–26 we hypothesized that its blockade could have a protective role in adriamycin-induced FSGS. Several studies have shown that the blockade and deletion of this receptor are associated with less inflammation and fibrosis,23,24,27,28 but no data were reported in FSGS.
Focal and segmental glomerulosclerosis (FSGS) is one of the most important causes of end-stage renal failure. The bradykinin B1 receptor has been associated with tissue inflammation and renal fibrosis. To test for a role of the bradykinin B1 receptor in podocyte injury, we pharmacologically modulated its activity at different time points in an adriamycin-induced mouse model of FSGS. Estimated albuminuria and urinary protein to creatinine ratios correlated with podocytopathy. Adriamycin injection led to loss of body weight, proteinuria, and upregulation of B1 receptor mRNA. Early treatment with a B1 antagonist reduced albuminuria and glomerulosclerosis, and inhibited the adriamycin-induced downregulation of podocin, nephrin, and α-actinin-4 expression. Moreover, delayed treatment with antagonist also induced podocyte protection. Conversely, a B1 agonist aggravated renal dysfunction and even further suppressed the levels of podocyte-related molecules. Thus, we propose that kinin has a crucial role in the pathogenesis of FSGS operating through bradykinin B1 receptor signaling.
Genomic phenotype of non-cultured pulmonary fibroblasts in idiopathic pulmonary fibrosis
2010, Genomics
Activated fibroblasts are the central effector cells of the progressive fibrotic process in idiopathic pulmonary fibrosis (IPF). Characterizing the genomic phenotype of isolated fibroblasts is essential to understanding IPF pathogenesis. Comparing the genomic phenotype of non-cultured pulmonary fibroblasts from advanced IPF patients' and normal lungs revealed novel genes, biological processes and concomitant pathways previously unreported in IPF fibroblasts. We demonstrate altered expression in proteasomal constituents, ubiquitination-mediators, Wnt, apoptosis and vitamin metabolic pathways and cell cycle regulators, suggestive of loss of cellular homeostasis. Specifically, FBXO32, CXCL14, BDKRB1 and NMNAT1 were up-regulated, while RARA and CDKN2D were down-regulated. Paradoxically, pro-apoptotic inducers TNFSF10, BAX and CASP6 were also found to be increased. This comprehensive description of altered gene expression in isolated IPF fibroblasts underscores the complex biological processes characteristic of IPF and may provide a foundation for future research into this devastating disease.

View all citing articles on Scopus

^☆: Support: This work was supported by the Brazilian Gorvenement Fundação de Apoio à Pesquisa do Estado de São Paulo (FAPESP). Grants numbers: 04/08311-6, 05/50085-6, 07/07139-3 and 06/03982-5.

View full text

Deletion of bradykinin B1 receptor reduces renal fibrosis☆

Abstract

Introduction

Section snippets

Animals

Experimental model of unilateral ureteral obstruction

Bradykinin B1R expression after UUO

Deletion of B1R and the development of fibrosis

Discussion

Am J Kidney Dis

Kidney Int

Kidney Int

Kidney Int

Transplant Proc

J Biol Chem

Trends Neurosci

Eur J Pharmacol

FEBS Lett

Int Immunopharmacol

Kidney Int

Kidney Int

Kidney Int

Urology

Kidney Int

J Dermatol Sci

Kidney Int

Urology

Common and unique mechanisms regulate fibrosis in various fibroproliferative diseases

J Clin Invest

Myofibroblasts and mechano-regulation of connective tissue remodelling

Nat Rev Mol Cell Biol

Mechanisms of disease: mechanisms of hepatic fibrosis and therapeutic implications

Nat Clin Pract Gastroenterol Hepatol

Obstructive nephropathy

Kidney Int

The role of growth factors, cytokines, and vasoactive compounds in obstructive nephropathy

Semin Nephrol

Enhanced expression of renal endothelin-converting enzyme-1 and endothelin-A-receptor mRNA in rats with interstitial fibrosis following ureter ligation

J Cardiovasc Pharmacol

Reduced angiotensinogen expression attenuates renal interstitial fibrosis in obstructive nephropathy in mice

J Clin Invest

Quantification of TGF-beta1 mRNA along rat nephron in obstructive nephropathy

Am J Physiol Renal Physiol

Identification and characterization of a fibroblast marker: FSP1

J Cell Biol