Renal Bioengineering Unit, Department of Medicine, University College Medical School, University College London, The Rayne Institute, London WC1E 6JJ, United Kingdom
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ABSTRACT |
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To understand how isolation and explantation of glomeruli affect the function of resident cells, the present study investigated the transcriptional profile of explanted normal glomeruli. We found that ex vivo incubation of glomeruli spontaneously expressed monocyte chemoattractant protein-1 (MCP-1) and stromelysin, the genes regulated by activator protein-1 (AP-1). The expression was suppressed by heparin and quercetin, the drugs with anti-AP-1 activities. The gene expression was preceded by 1) induction of AP-1 components c-fos and c-jun and 2) phosphorylation of extracellular signal-regulated kinase (ERK), p38 mitogen-activated protein (MAP) kinase, and c-Jun NH2-terminal kinase (JNK), the upstream inducers/activators of AP-1. Suppression of ERK by PD098059 abrogated induction of c-fos and c-jun, and the p38 MAP kinase inhibitor SB203580 attenuated c-fos expression. Furthermore, treatment with either PD098059, SB203580, or the JNK-AP-1 inhibitor curcumin diminished the expression of MCP-1 and stromelysin. The transcriptional profile of glomerular cells thus alters dramatically after explantation of glomeruli. It is, at least in part, due to activation of multiple MAP kinases that lead to induction of AP-1-dependent gene expression.
monocyte chemoattractant protein-1; stromelysin; extracellular signal-regulated kinase; p38 mitogen-activated protein kinase; c-Jun NH2 kinase
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INTRODUCTION |
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FOR MANY YEARS, ISOLATED GLOMERULI have been used for investigation of glomerular pathophysiology. Explantation of glomeruli enables the examination of production of bioactive substances by glomerular cells and determination of environmental factors that modulate glomerular cell activity (2, 14, 36). Despite the extensive use of isolated glomeruli, little is understood about how isolation and explantation per se affect the structure and function of the glomerulus. We recently investigated the incidence of apoptosis in explanted rat glomeruli and found that significant numbers of resident cells, mainly podocytes, spontaneously undergo apoptosis immediately after ex vivo incubation of normal glomeruli (9). Apoptosis requires activation of particular intracellular signaling pathways. We speculated that certain signaling molecules, including kinases and transcription factors, may be spontaneously mobilized and activated in isolated glomeruli. To examine this possibility, we investigated the transcriptional profile of explanted normal glomeruli.
The expression of several genes was tested for this purpose. Endothelial nitric oxide synthase (eNOS) and glomerular epithelial protein-1 (GLEPP1) were examined as the transcripts normally expressed in glomeruli. eNOS is constitutively expressed in the glomerular endothelium and participates in continuous production of nitric oxide in the glomerulus (6, 30). In contrast to inducible NOS, which is upregulated under pathological circumstances, expression levels of eNOS may be downregulated in disease conditions (6). GLEPP1 is a receptor-like transmembrane protein tyrosine phosphatase that is expressed exclusively in podocytes (41). The expression level of GLEPP1 diminishes in experimental and human glomerulonephritis in which podocytes are affected (44).
Expression of monocyte chemoattractant protein-1 (MCP-1) and stromelysin was examined as the transcripts that are normally undetectable but are inducible under pathological conditions. MCP-1 is a member of the chemokine family and specifically attracts monocytes (23). During the course of glomerulonephritis, expression of MCP-1 is induced in resident glomerular cells (32, 39). Stromelysin is a matrix-degrading metalloproteinase that plays an important role in the degradation of extracellular matrix. Expression of stromelysin is induced in inflamed glomeruli (27) and associated with aberrant function of glomerular cells and the glomerular basement membrane (17, 37). Cultured mesangial cells, as well as isolated glomeruli, express stromelysin in response to activated macrophages and macrophage-derived proinflammatory cytokines (14, 16, 18).
During this study, we found that MCP-1 and stromelysin were dramatically induced in explanted glomeruli. The 5'-flanking regions of MCP-1 and stromelysin genes contain the 12-O-tetradecanoylphorbol 13-acetate (TPA) response element (TRE), and expression of these genes is regulated by activator protein-1 (AP-1) (13, 34, 38, 40). In the present report, we investigate whether AP-1 is upregulated in explanted glomeruli, and, if so, what kinds of upstream events are involved in the AP-1-mediated gene expression.
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MATERIALS AND METHODS |
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Isolation and explantation of glomeruli. Normal glomeruli were isolated from adult male Sprague-Dawley rats (250-300 g body wt) by use of the conventional sieving method (35). In brief, kidneys were minced well on ice and forced through sequential steel sieves, and glomeruli were collected with the use of cold phosphate-buffered saline (PBS). In some experiments, kidneys were perfused through the renal artery with cold DMEM-Ham's F-12 (DME-F12; GIBCO, Gaithersburg, MD) and used to prepare blood-free glomeruli. After isolation, glomeruli were suspended in DME-F12 supplemented with 100 U/ml of penicillin G, 100 µg/ml of streptomycin, 0.25 µg/ml of amphotericin B, and 1% fetal calf serum (FCS; GIBCO).
Glomeruli lacking mesangial cells were created by an anti-mesangial cell monoclonal antibody, 1-22-3 (12). In the rat kidney, the epitope recognized by 1-22-3 localizes specifically on the surface of mesangial cells. When 1-22-3 is injected into the venous circulation, selective mesangial damage occurs within a few hours. After 2 h, the majority of mesangial cells are destroyed without any morphological changes in podocytes, endothelial cells, and the glomerular basement membrane (42). To prepare mesangial cell-ablated glomeruli, 1-22-3 (a generous gift from Dr. F. Shimizu, Niigata Univ., Japan) was injected into the tail veins of rats, as described before (20). After 2 h, glomeruli were isolated and used for experiments. Ex vivo incubation of isolated glomeruli was performed in 24-well tissue culture plates at 37°C in a 5% CO2 atmosphere for up to 24 h, generally in the presence of 1% FCS. In some experiments, glomeruli were incubated without serum in the absence or presence of 1% bovine serum albumin. For Northern analysis, glomeruli were frozen in a deep freezer (Pharmacological manipulations. Isolated normal glomeruli were incubated for 24 h in the absence or presence of heparin (100 U/ml; Sigma Immunochemicals, St. Louis, MO) and quercetin (50 µM, Sigma), the inhibitors of glomerular cell apoptosis with potential anti-AP-1 properties (10, 15). To examine roles of extracellular signal-regulated kinase (ERK), p38 mitogen-activated protein (MAP) kinase, c-Jun NH2-terminal kinase (JNK), and AP-1, isolated glomeruli were incubated in the absence or presence of the MAP kinase kinase (MEK)1 inhibitor PD098059 (50 µM, a gift from Dr. A. R. Saltiel) (5), the p38 MAP kinase inhibitor SB203580 (25 µM; Calbiochem-Novabiochem, Nottingham, UK), or the JNK-AP-1 inhibitor curcumin (20 µM, Sigma) (3, 8). After the incubation, glomeruli were washed with cold PBS and used for Northern blot analysis and kinase assays, as described below. Incubation times used for individual experiments were as follows: 0.5 h for kinase assays of ERK, p38 MAP kinase, and JNK; 0.5-2 h for Northern blot analysis of c-fos and c-jun; and 24 h for Northern analysis of eNOS, GLEPP1, MCP-1, and stromelysin.
Northern blot analysis. Northern blot analysis was performed as described previously (19). In brief, total RNA was extracted from glomeruli (0.5-1 × 104/sample) by a single-step method (4), and RNA samples (10-15 µg/lane) were electrophoresed on 1.2% agarose gels and transferred onto nitrocellulose membranes. For hybridization, cDNAs were labeled with [32P]dCTP by use of the random priming method. As probes, cDNAs for bovine eNOS (28), rabbit GLEPP1 (41), mouse JE/MCP-1 (31), rat stromelysin (25), human c-Fos (33), human c-Jun (26), and human 28S rRNA (American Type Culture Collection, Manassas, VA) were used.
Kinase assays.
Phosphorylation of ERK and p38 MAP kinase was evaluated by Western blot
analysis, as described before (29). In brief, glomeruli (0.5-1 × 104/sample) were lysed with 200 µl of
sample buffer (4% SDS, 10% glycerol, 0.006% bromophenol blue, and
2% -mercaptoethanol in 250 mM Tris · HCl; pH 6.8) and
boiled for 5 min. Samples were passaged several times through 23-gauge
needles. After centrifugation, supernatants were electrophoresed in
10% acrylamide gels and transferred onto nitrocellulose membranes.
Analyses were performed with the use of PhosphoPlus MAPK antibody kit
and PhosphoPlus p38 MAP kinase antibody kit (New England Biolabs,
Herts, UK), following protocols provided by the manufacturer.
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RESULTS |
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Alteration in the transcriptional profile of explanted normal
glomeruli.
Isolated normal rat glomeruli were incubated in the presence of 1% FCS
for 24 h. Northern blot analysis was performed on the expression
of eNOS, GLEPP1, MCP-1, and stromelysin (Fig.
1). Immediately after isolation, constitutive
expression of eNOS and GLEPP1 was detectable, whereas transcripts for
MCP-1 and stromelysin were not detected. After ex vivo incubation,
substantial induction of MCP-1 and stromelysin mRNAs was observed. In
contrast, expression of GLEPP1, a marker of podocytes, was dramatically
decreased in explanted glomeruli, possibly due to apoptosis of
podocytes (9). Expression of eNOS, a marker of endothelial
cells, was maintained constant during the incubation.
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Spontaneous induction of AP-1 components and activation of MAP
kinases in explanted glomeruli.
TRE is located in the promoter regions of both MCP-1 and stromelysin
genes, and their expression is regulated by AP-1 mainly composed of Fos
and Jun (13, 24, 38, 40). To examine the role of AP-1 in
the spontaneous gene expression, expression of c-fos and
c-jun mRNAs was examined. Isolated glomeruli were incubated ex vivo for 0.5-2 h and subjected to Northern blot analysis (Fig. 3A). Immediately after isolation,
glomeruli did not express c-fos and c-jun. Both
mRNAs were rapidly induced during the ex vivo incubation within 1 h.
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Roles of MAP kinases and c-Jun/AP-1 in the induction of MCP-1 and
stromelysin.
To examine whether activated ERK and p38 MAP kinase are required for
the spontaneous induction of the AP-1-controlled genes, isolated
glomeruli were incubated in the absence or presence of PD098059 and
SB203580, the specific inhibitors of MEK1 and p38, respectively.
Northern blot analysis showed that the spontaneous expression of
c-fos was attenuated by both MAP kinase inhibitors (Fig.
4A). Expression of
c-jun was inhibited only by PD098059. Consistently, both
inhibitors attenuated expression of MCP-1 and stromelysin in explanted
glomeruli (Fig. 4B).
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DISCUSSION |
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In this report, we showed that the transcriptional profile of isolated glomeruli alters dramatically after ex vivo incubation. We found that the podocyte marker GLEPP1 was markedly suppressed, whereas expression of MCP-1 and stromelysin was substantially upregulated. A recent report showed that resident cells, mainly podocytes, spontaneously undergo apoptosis immediately after explantation of glomeruli (9). The dramatic downregulation of GLEPP1 may be explained by a decrease in the number of viable podocytes in explanted glomeruli. However, heparin and quercetin, which attenuate spontaneous apoptosis of podocytes at the early stage (2 h) (10, 15), did not affect the decrease in the GLEPP1 mRNA level. This result indicated another possibility, that GLEPP1 expression could be transcriptionally suppressed in explanted glomeruli, although it has not been determined whether these drugs can block apoptosis of podocytes even at the late stage (24 h).
The induction of MCP-1 and stromelysin was observed in both blood-containing glomeruli and blood-free glomeruli. The spontaneous gene expression thus occurred in resident glomerular cells. The experimental results using mesangial cell-ablated glomeruli suggested that mesangial cells are responsible for the expression of stromelysin but not MCP-1.
The spontaneous induction of MCP-1 and stromelysin was likely due to rapid upregulation of AP-1, because 1) expression of MCP-1 and stromelysin is regulated by AP-1 (13, 34, 38, 40), 2) rapid induction of c-fos and c-jun was observed in explanted glomeruli, and 3) the pharmacological inhibitor of JNK-AP-1, curcumin, abrogated the expression of both MCP-1 and stromelysin. Furthermore, activation of multiple MAP kinase pathways was identified as an upstream event involved in the induction of AP-1 components and AP-1-controlled gene expression. That is, both inducers of AP-1 components (ERK, p38, and JNK) and activators of AP-1 (JNK and p38) (43) were phosphorylated in isolated glomeruli within 30 min after the explantation. Inhibition of either ERK or p38 MAP kinase attenuated induction of AP-1 components and expression of MCP-1 and stromelysin. These results indicate that immediately after explantation, MAP kinase pathways are spontaneously activated, leading to consequent induction of the AP-1-mediated gene expression.
Interestingly, we found that the induction of MCP-1 and stromelysin was substantially inhibited by the potential anti-inflammatory drugs heparin and quercetin. These effects are consistent with their inhibitory effects on the cytokine-induced expression of MCP-1 and stromelysin in cultured mesangial cells (10, 11). Heparin and quercetin are known to inhibit AP-1 in mesangial cells (10, 46). These data further support the idea that the spontaneous induction of MCP-1 and stromelysin is caused by upregulation of the AP-1 pathway.
What is the trigger for spontaneous upregulation of MAP kinases in explanted glomeruli? One possibility is that, during the sieving procedure, mechanical stress exerted on glomeruli may have activated MAP kinases. Previous studies showed that, in cardiac myocytes and endothelial cells, mechanical stress incited activation of ERKs, JNKs, and/or p38 MAP kinase and subsequent increase in the AP-1 activity (21, 22, 24). Other environmental factors including altered oxygen tension, reduced supply of nutrients, impaired removal of metabolic products, or lack of hemodynamic forces could also have contributed to the MAP kinase activation in culture. Contribution of blood components (e.g., leukocytes, platelets, and plasma/serum growth factors) is unlikely, because the induction of MCP-1 and stromelysin was similarly observed in blood-free glomeruli and under serum-free culture conditions.
MAP kinase-AP-1 pathways regulate a wide range of genes involved in
various biological processes, including cell proliferation, differentiation, and apoptosis (1, 43). From this
viewpoint, our data indicate a possibility that isolation and
explantation per se may trigger not only expression of some genes but
also substantial alteration in the glomerular structure and function. Indeed, previous reports showed that isolated, intact glomeruli spontaneously release proinflammatory cytokine tumor necrosis factor- (7) and exhibit apoptotic cell death
(9). The peculiar biochemical properties of isolated
glomeruli should be considered carefully for experimental design and
interpretation of data when ex vivo incubation of glomeruli is used for investigation.
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ACKNOWLEDGEMENTS |
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We appreciate the kind gift of 1-22-3 from Dr. Fujio Shimizu (Niigata Univ.).
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FOOTNOTES |
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This work was supported in part by grants from Baxter Healthcare Corporation (Extramural Grant Program), Wellcome Trust, and National Kidney Research Fund (to M. Kitamura).
Address for reprint requests and other correspondence: M. Kitamura, Renal Bioengineering Unit, Dept. of Medicine, Univ. College Medical School, Univ. College London, 7th Floor, Jules Thorn Institute, Middlesex Hospital, Mortimer St., London W1T 3AA, United Kingdom (E-mail: m.kitamura{at}medicine.ucl.ac.uk).
The costs of publication of this article were defrayed in part by the payment of page charges. The article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
Received 22 November 1999; accepted in final form 12 July 2000.
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REFERENCES |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
1.
Angel, P,
and
Karin M.
The role of Jun, Fos and the AP-1 complex in cell proliferation and transformation.
Biochim Biophys Acta
1072:
129-157,
1991[ISI][Medline].
2.
Baumbach, L.
Renin release from isolated rat glomeruli: effects of colchicine, vinca alkaloids, dimethylsulphoxide, and cytochalasins.
J Physiol (Lond)
299:
145-155,
1980[Abstract].
3.
Chen, YR,
and
Tan TH.
Inhibition of the c-Jun N-terminal kinase (JNK) signaling pathway by curcumin.
Oncogene
17:
173-178,
1998[ISI][Medline].
4.
Chomczynski, P,
and
Sacchi N.
Single-step method of RNA isolation by acid guanidinium thiocyanate phenol chloroform extraction.
Anal Biochem
162:
156-159,
1987[ISI][Medline].
5.
Dudley, DT,
Pang L,
Decker SJ,
Bridges AJ,
and
Saltiel AR.
A synthetic inhibitor of the mitogen-activated protein kinase cascade.
Proc Natl Acad Sci USA
92:
7686-7689,
1995[Abstract].
6.
Furusu, A,
Miyazaki M,
Abe K,
Tsukasaki S,
Shioshita K,
Sasaki O,
Miyazaki K,
Ozono Y,
Koji T,
Harada T,
Sakai H,
and
Kohno S.
Expression of endothelial and inducible nitric oxide synthase in human glomerulonephritis.
Kidney Int
53:
1760-1768,
1998[ISI][Medline].
7.
Hruby, ZW,
and
Lowry RP.
Spontaneous release of tumor necrosis factor- by isolated renal glomeruli and cultured glomerular mesangial cells.
Clin Immunol Immunopathol
59:
156-164,
1991[ISI][Medline].
8.
Huang, TS,
Lee SC,
and
Lin JK.
Suppression of c-Jun/AP-1 activation by an inhibitor of tumor promotion in mouse fibroblast cells.
Proc Natl Acad Sci USA
88:
5292-5296,
1991[Abstract].
9.
Ishikawa, Y,
and
Kitamura M.
Spontaneous apoptosis of podocytes in explanted glomeruli.
Kidney Int
54:
2008-2013,
1998[ISI][Medline].
10.
Ishikawa, Y,
and
Kitamura M.
Inhibition of glomerular cell apoptosis by heparin.
Kidney Int
56:
954-963,
1999[ISI][Medline].
11.
Ishikawa, Y,
Sugiyama H,
Stylianou E,
and
Kitamura M.
Bioflavonoid quercetin inhibits interleukin-1-induced transcriptional expression of monocyte chemoattractant protein-1 in glomerular cells via suppression of nuclear factor-B.
J Am Soc Nephrol
10:
2290-2296,
1999
12.
Kawachi, H,
Orisaka M,
Matsui K,
Iwanaga T,
Toyabe S,
Oite T,
and
Shimizu F.
Epitope-specific induction of mesangial lesions with proteinuria by a MoAb against mesangial cell surface antigen.
Clin Exp Immunol
88:
399-404,
1992[ISI][Medline].
13.
Kerr, LD,
Holt JT,
and
Matrisian LM.
Growth factors regulate transin gene expression by c-fos-dependent and c-fos-independent pathways.
Science
242:
1424-1427,
1988[ISI][Medline].
14.
Kitamura, M.
TGF-1 as an endogenous defender against macrophage-triggered stromelysin gene expression in the glomerulus.
J Immunol
160:
5163-5168,
1998
15.
Kitamura, M,
and
Ishikawa Y.
Oxidant-induced apoptosis of glomerular cells: intracellular signaling and its intervention by bioflavonoids.
Kidney Int
56:
1223-1229,
1999[ISI][Medline].
16.
Kitamura, M,
Maruyama N,
Mitarai T,
Nagasawa R,
Yokoo T,
and
Sakai O.
Heparin selectively inhibits gene expression of matrix metalloproteinase transin in cultured mesangial cells.
Biochem Biophys Res Commun
203:
1333-1338,
1994[ISI][Medline].
17.
Kitamura, M,
Shirasawa T,
and
Maruyama N.
Gene transfer of metalloproteinase transin induces aberrant behavior of cultured mesangial cells.
Kidney Int
45:
1580-1586,
1994[ISI][Medline].
18.
Kitamura, M,
and
Sütö TS.
Transfer of genetically engineered macrophages into the glomerulus.
Kidney Int
51:
1274-1279,
1997[ISI][Medline].
19.
Kitamura, M,
Sütö T,
Yokoo T,
Shimizu F,
and
Fine LG.
Transforming growth factor-1 is the predominant paracrine inhibitor of macrophage cytokine synthesis produced by glomerular mesangial cells.
J Immunol
156:
2964-2971,
1996[Abstract].
20.
Kitamura, M,
Taylor S,
Unwin R,
Burton S,
Shimizu F,
and
Fine LG.
Gene transfer into the rat renal glomerulus via a mesangial cell vector: site-specific delivery, in situ amplification, and sustained expression of an exogenous gene in vivo.
J Clin Invest
94:
497-505,
1994[ISI][Medline].
21.
Komuro, I,
Kudo S,
Yamazaki T,
Zou Y,
Shiojima I,
and
Yazaki Y.
Mechanical stretch activates the stress-activated protein kinases in cardiac myocytes.
FASEB J
10:
631-636,
1996
22.
Kudoh, S,
Komuro I,
Hiroi Y,
Zou Y,
Harada K,
Sugaya T,
Takekoshi N,
Murakami K,
Kadowaki T,
and
Yazaki Y.
Mechanical stretch induces hypertrophic responses in cardiac myocytes of angiotensin II type 1a receptor knockout mice.
J Biol Chem
273:
24037-24043,
1998
23.
Leonard, EJ,
and
Yoshimura T.
Human monocyte chemoattractant protein-1 (MCP-1).
Immunol Today
11:
97-101,
1990[ISI][Medline].
24.
Li, YS,
Shyy JY,
Li S,
Lee J,
Su B,
Karin M,
and
Chien S.
The Ras-JNK pathway is involved in shear-induced gene expression.
Mol Cell Biol
16:
5947-5954,
1996[Abstract].
25.
Matrisian, LM,
Glaichenhaus N,
Gesnel MC,
and
Breathnach R.
Epidermal growth factor and oncogenes induce transcription of the same cellular mRNA in rat fibroblasts.
EMBO J
4:
1435-1440,
1985[Abstract].
26.
McDonnell, SE,
Kerr LD,
and
Matrisian LM.
Epidermal growth factor stimulation of stromelysin mRNA in rat fibroblasts requires induction of proto-oncogenes c-fos and c-jun and activation of protein kinase C.
Mol Cell Biol
10:
4284-4293,
1990[ISI][Medline].
27.
Miyazaki, M,
Koji T,
Furusu A,
Abe K,
Ozono Y,
Hara K,
Harada T,
Nakane PK,
Suzuki D,
Yagame M,
Endoh M,
Nomoto Y,
and
Sakai H.
Expression of stromelysin mRNA and TIMP mRNA in human diseased kidneys (Abstract).
J Am Soc Nephrol
6:
902,
1995[ISI].
28.
Nishida, K,
Harrison DG,
Navas JP,
Fisher AA,
Dockery SP,
Uematsu M,
Nerem RM,
Alexander RW,
and
Murphy TJ.
Molecular cloning and characterization of the constitutive bovine aortic endothelial cell nitric oxide synthase.
J Clin Invest
90:
2092-2096,
1992[ISI][Medline].
29.
Ogura, M,
and
Kitamura M.
Oxidant stress incites spreading of macrophages via extracellular signal-regulated kinases and p38 mitogen-activated protein kinase.
J Immunol
161:
3569-3574,
1998
30.
Raij, L,
and
Baylis C.
Glomerular actions of nitric oxide.
Kidney Int
48:
20-32,
1995[ISI][Medline].
31.
Rollins, BJ,
Morrison ED,
and
Stiles CD.
Cloning and expression of JE, a gene inducible by platelet-derived growth factor and whose product has cytokine-like properties.
Proc Natl Acad Sci USA
85:
3738-3742,
1988[Abstract].
32.
Rovin, BH,
Yoshimura T,
and
Tan L.
Cytokine-induced production of monocyte chemoattractant protein-1 by cultured human mesangial cells.
J Immunol
148:
2148-2153,
1992
33.
Ruther, U,
Wagner EF,
and
Muller R.
Analysis of the differentiation-promoting potential of inducible c-fos genes introduced into embryonal carcinoma cells.
EMBO J
4:
1775-1781,
1985[Abstract].
34.
Sato, H,
and
Seiki M.
Regulatory mechanism of 92 kDa type IV collagenase gene expression which is associated with invasiveness of tumor cells.
Oncogene
8:
395-405,
1993[ISI][Medline].
35.
Schlondorff, D.
Preparation and study of isolated glomeruli.
Methods Enzymol
191:
130-140,
1990[Medline].
36.
Schlondorff, D,
Roczniak S,
Satriano JA,
and
Folkert VW.
Prostaglandin synthesis by isolated rat glomeruli: effect of angiotensin II.
Am J Physiol Renal Fluid Electrolyte Physiol
239:
F486-F495,
1980
37.
Sharma, R,
Suzuki K,
Nagase H,
and
Savin VJ.
Matrix metalloproteinase (stromelysin-1) increases the albumin permeability of isolated rat glomeruli.
J Lab Clin Med
128:
297-303,
1996[ISI][Medline].
38.
Shyy, YZ,
Li YS,
and
Kolattukudy PE.
Structure of human monocyte chemotactic protein gene and its regulation by TPA.
Biochem Biophys Res Commun
169:
346-351,
1990[ISI][Medline].
39.
Stahl, RAK,
Thaiss F,
Disser M,
Helmchen U,
Hora K,
and
Schlondorff D.
Increased expression of monocyte chemoattractant protein-1 in anti-thymocyte antibody-induced glomerulonephritis.
Kidney Int
44:
1036-1047,
1993[ISI][Medline].
40.
Takeshita, A,
Chen Y,
Watanabe A,
Kitano S,
and
Hanazawa S.
TGF- induces expression of monocyte chemoattractant JE/monocyte chemoattractant protein-1 via transcriptional factor AP-1 induced by protein kinase in osteoblastic cells.
J Immunol
155:
419-426,
1995[Abstract].
41.
Thomas, PE,
Wharram BL,
Goyal M,
Wiggins JE,
Holzman LB,
and
Wiggins RC.
GLEPP1, a renal glomerular epithelial cell (podocyte) membrane protein-tyrosine phosphatase. Identification, molecular cloning, and characterization in rabbit.
J Biol Chem
269:
19953-19962,
1994
42.
Toyabe, S,
and
Iwanaga T.
A structural study of proliferative nephritis induced experimentally by a monoclonal antibody against mesangial cells: replacement of mesangial cells by cells of the monocyte-macrophage system.
Virchows Archiv B Cell Pathol
61:
397-407,
1992[ISI].
43.
Whitmarsh, AJ,
and
Davis RJ.
Transcription factor AP-1 regulation by mitogen-activated protein kinase signal transduction pathways.
J Mol Med
74:
589-607,
1996[ISI][Medline].
44.
Yang, DH,
Goyal M,
Sharif K,
Kershaw D,
Thomas P,
Dysko R,
and
Wiggins R.
Glomerular epithelial protein 1 and podocalyxin-like protein 1 in inflammatory glomerular disease (crescentic nephritis) in rabbit and man.
Lab Invest
74:
571-584,
1996[ISI][Medline].
45.
Yokoo, T,
and
Kitamura M.
Opposite, binary regulatory pathways involved in IL-1-mediated stromelysin gene expression in rat mesangial cells.
Kidney Int
50:
894-901,
1996[ISI][Medline].
46.
Yokoo, T,
and
Kitamura M.
Unexpected protection of glomerular mesangial cells from oxidant-triggered apoptosis by bioflavonoid quercetin.
Am J Physiol Renal Physiol
273:
F206-F212,
1997
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