The Actions of C-Type Natriuretic Peptide on Human Mesangial Cell Apoptosis and P53 Expression

2000 ◽  
Vol 6 (S2) ◽  
pp. 624-625
Author(s):  
K. Seta ◽  
C. Wei

C-type natriuretic peptide (CNP) of endothelial cell origin via NPR-B receptor mediates antimitogenic and vasodilatory actions. As a circulating endocrine system, CNP plays a fundamental role in cardiorenal regulation. However, the actions of CNP on renal mesangial cell apoptosis remain poorly defined. Apoptosis might plays an important role during development of renal glomerular mesangial cells pathophysiology. The mechanisms of apoptosis include p53-dependent pathway and p53-independent pathway.The hypothesis of this study is that CNP induces apoptosis through the process involving p53 gene in human glomerular mesangial cells via natriuretic peptide biological receptor. Therefore, the current study was designed to investigate the effects of CNP on apoptosis and p53 expression in human mesangial cell in the absence or presence of CNP biological receptor antagonist.Cultured human mesangial cells (Clontech Lab., San Diego, CA) was incubated for 24 hours in the absence or presence of CNP (10-7 M). These studies were repeated with HS 142-1 (HS, 10-5 M), a CNP biological receptor antagonist.

2011 ◽  
Vol 301 (5) ◽  
pp. F1131-F1138 ◽  
Author(s):  
Ramadan M. Sarrab ◽  
Rachel Lennon ◽  
Lan Ni ◽  
Matthew D. Wherlock ◽  
Gavin I. Welsh ◽  
...  

The aim of this study was to establish an immortalized human mesangial cell line similar to mesangial cells in vivo for use as a tool for understanding glomerular cell function. Mesangial cells were isolated from glomerular outgrowths from a normal human kidney, then retrovirally transfected with a temperature-sensitive SV40T antigen+human telomerase (hTERT). Mesangial cells exhibited features of compact cells with small bodies in a confluent monolayer at 33°C, but the cell shape changed to flat and stellate after 5 days in growth-restrictive conditions (37°C). Western blot and immunofluorescence analysis showed that podocyte markers (nephrin, CD2AP, podocin, Wilms' tumor-1) and an endothelial-specific molecule (VE-cadherin) were not detectable in this cell line, whereas markers characteristic of mesangial cells (α-SMA, fibronectin, and PDGFβ-R) were strongly expressed. In migration assays, a significant reduction in wound surface was observed in podocyte and endothelial cells as soon as 12 h (75 and 62%, respectively) and complete wound closure after 24 h. In contrast, no significant change was observed in mesangial cells after 12 h, and even after 48 h the wounds were not completely closed. Until now, conditionally immortalized podocyte and endothelial cell lines derived from mice and humans have been described, and this has greatly boosted research on glomerular physiology and pathology. We have established the first conditionally immortalized human glomerular mesangial cell line, which will be an important adjunct in studies of representative glomerular cells, as well as in coculture studies. Unexpectedly, mesangial cells' ability to migrate seems to be slower than for other glomerular cells, suggesting this line will demonstrate functional properties distinct from previously available mesangial cell cultures. This conditionally immortalized human mesangial cell line represents a new tool for the study of human mesangial cell biology in vitro.


1990 ◽  
Vol 172 (6) ◽  
pp. 1843-1852 ◽  
Author(s):  
P A Marsden ◽  
B J Ballermann

Endothelium-derived nitric oxide (NO) causes vasodilatation by activating soluble guanylate cyclase, and glomerular mesangial cells respond to NO with elevations of intracellular guanosine 3',5'-cyclic monophosphate (cGMP). We explored whether mesangial cells can be stimulated to produce NO and whether NO modulates mesangial cell function in an autocrine or paracrine fashion. Tumor necrosis factor alpha (TNF-alpha) raised mesangial cell cGMP levels in a time- and concentration-dependent manner (threshold dose 1 ng/ml, IC50 13.8 ng/ml, maximal response 100 ng/ml). TNF-alpha-induced increases in mesangial cGMP content were evident at 8 h and maximal at 18-24 h. The TNF-alpha-induced stimulation of mesangial cell cGMP production was abrogated by actinomycin D or cycloheximide suggesting dependence on new RNA or protein synthesis. Hemoglobin and methylene blue, both known to inhibit NO action, dramatically reduced TNF-alpha-induced mesangial cell cGMP production. Superoxide dismutase, known to potentiate NO action, augmented the TNF-alpha-induced effect. Ng-monomethyl-L-arginine (L-NMMA) decreased cGMP levels in TNF-alpha-treated, but not vehicle-treated mesangial cells in a concentration-dependent manner (IC50 53 microM). L-arginine had no effect on cGMP levels in control or TNF-alpha-treated mesangial cells but reversed L-NMMA-induced inhibition. Interleukin 1 beta and lipopolysaccharide (LPS), but not interferon gamma, also increased mesangial cell cGMP content. Transforming growth factor beta 1 blunted the mesangial cell response to TNF-alpha. TNF-alpha-induced L-arginine-dependent increases in cGMP were also evident in bovine renal artery vascular smooth muscle cells, COS-1 cells, and 1502 human fibroblasts. These findings suggest that TNF-alpha induces expression in mesangial cell of an enzyme(s) involved in the formation of L-arginine-derived NO. Moreover, the data indicate that NO acts in an autocrine and paracrine fashion to activate mesangial cell soluble guanylate cyclase. Cytokine-induced formation of NO in mesangial and vascular smooth muscle cells may be implicated in the pathogenesis of septic shock.


2020 ◽  
Vol 295 (42) ◽  
pp. 14262-14278
Author(s):  
Soumya Maity ◽  
Falguni Das ◽  
Balakuntalam S. Kasinath ◽  
Nandini Ghosh-Choudhury ◽  
Goutam Ghosh Choudhury

Interaction of transforming growth factor-β (TGFβ)-induced canonical signaling with the noncanonical kinase cascades regulates glomerular hypertrophy and matrix protein deposition, which are early features of glomerulosclerosis. However, the specific target downstream of the TGFβ receptor involved in the noncanonical signaling is unknown. Here, we show that TGFβ increased the catalytic loop phosphorylation of platelet-derived growth factor receptor β (PDGFRβ), a receptor tyrosine kinase expressed abundantly in glomerular mesangial cells. TGFβ increased phosphorylation of the PI 3-kinase–interacting Tyr-751 residue of PDGFRβ, thus activating Akt. Inhibition of PDGFRβ using a pharmacological inhibitor and siRNAs blocked TGFβ-stimulated phosphorylation of proline-rich Akt substrate of 40 kDa (PRAS40), an intrinsic inhibitory component of mTORC1, and prevented activation of mTORC1 in the absence of any effect on Smad 2/3 phosphorylation. Expression of constitutively active myristoylated Akt reversed the siPDGFRβ-mediated inhibition of mTORC1 activity; however, co-expression of the phospho-deficient mutant of PRAS40 inhibited the effect of myristoylated Akt, suggesting a definitive role of PRAS40 phosphorylation in mTORC1 activation downstream of PDGFRβ in mesangial cells. Additionally, we demonstrate that PDGFRβ-initiated phosphorylation of PRAS40 is required for TGFβ-induced mesangial cell hypertrophy and fibronectin and collagen I (α2) production. Increased activating phosphorylation of PDGFRβ is also associated with enhanced TGFβ expression and mTORC1 activation in the kidney cortex and glomeruli of diabetic mice and rats, respectively. Thus, pursuing TGFβ noncanonical signaling, we identified how TGFβ receptor I achieves mTORC1 activation through PDGFRβ-mediated Akt/PRAS40 phosphorylation to spur mesangial cell hypertrophy and matrix protein accumulation. These findings provide support for targeting PDGFRβ in TGFβ-driven renal fibrosis.


1992 ◽  
Vol 263 (1) ◽  
pp. F97-F102 ◽  
Author(s):  
D. W. Coyne ◽  
M. Nickols ◽  
W. Bertrand ◽  
A. R. Morrison

The cytokines, interleukin-1 (IL-1) and tumor necrosis factor (TNF), potently induce prostaglandin formation in glomerular mesangial cells. Mechanisms by which these cytokines stimulate prostaglandin formation vary among cell types. We investigated whether alterations in phospholipase A2 (PLA2) or cyclooxygenase (COX) mass and activity contribute to the changes in mesangial cell prostaglandin production. These cytokines induced COX activity and mass in a time-dependent manner, which paralleled prostaglandin production. IL-1 increased COX mass approximately threefold by 24 h. TNF had a much smaller effect, although it appeared to be additive with IL-1. IL-1-induced COX mass was maintained at an increased level for at least 48 h. The glucocorticoid dexamethasone (DEX) virtually abolished prostaglandin production and blocked cytokine induction of COX activity and mass. DEX did not reduce COX activity or mass below the basal, serum-fed levels, however. By utilizing stable isotope methods, we could demonstrate that IL-1 increased free arachidonate levels, implying new PLA2 synthesis over a time course that was maximal at 6 h and was cycloheximide and actinomycin D sensitive. These data demonstrate that the cytokines IL-1 and TNF enhance synthesis of COX and PLA2, contributing to increased prostaglandin production. Cytokine-stimulated prostaglandin production ceases when cells are also treated with DEX, although control levels of COX activity and mass remain. This occurs because DEX inhibits the IL-1-induced enhanced arachidonate release.


1989 ◽  
Vol 257 (3) ◽  
pp. F478-F485
Author(s):  
T. C. Knauss ◽  
P. Mene ◽  
S. A. Ricanati ◽  
M. Kester ◽  
G. R. Dubyak ◽  
...  

Glomerulonephritis is frequently associated with immunoglobulin deposition in the mesangium. We had previously shown that contractile, rat mesangial cells in culture synthesize superoxide anion after binding immune complexes (IC) in a manner dependent on the Fc region of immunoglobulin G (IgG). We now studied the effects of soluble IC on mesangial cell cytosolic free calcium ([Ca2+]i) and phosphatidylinositol turnover as putative mechanisms of transmembrane signaling as well as prostaglandin biosynthesis and contraction. IC (500 micrograms specific antibody) raised [Ca2+]i in mesangial cells loaded with fura-2 from resting levels of 100.4 +/- 8.0 to a peak of 282.3 +/- 31.5 nM in a dose-dependent manner. Removal of extracellular Ca2+ by ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid only slightly reduced peak, IC-stimulated [Ca2+]i to 236 +/- 18 nM but prevented the sustained phase of the response, indicating that IC both mobilized Ca2+ from intracellular stores and increased the influx of Ca2+ across the plasma membrane. IC did not increase water-soluble inositol phosphates, measured by anion-exchange chromatography of trichloroacetic acid-extracted cells but markedly stimulated PGE2 and thromboxane B2 synthesis in a dose- and time-dependent manner. Finally, IC (250 micrograms specific antibody) induced 45.8 +/- 10.1% of the cells to contract with an average decrease in cross-sectional surface area of 20.0 +/- 1.8% of basal as assessed by image-analysis microscopy. IC formed with F(ab')2 fragments of antibody and antigen or mixtures of antigen and nonimmune whole molecule antibody did not alter [Ca2+]i, induce prostaglandin synthesis, or stimulate mesangial cell contraction.(ABSTRACT TRUNCATED AT 250 WORDS)


1992 ◽  
Vol 2 (10) ◽  
pp. S88
Author(s):  
M Davies ◽  
G J Thomas ◽  
L D Shewring ◽  
R M Mason

In cultures of human adult glomerular mesangial cells, large chondroitin sulfate proteoglycans (CSPG) and small dermatan sulfate proteoglycans (DSPG) are synthesized. The large CSPG has a core protein, M(r) of 400,000 (major) and M(r) of 500,000 (minor), and binds to hyaluronic acid to form large aggregates. The two small DSPGs (Mr of approximately 350,000 and M(r) of approximately 200,000) were related to biglycan and decorin, respectively. The majority of these proteoglycans were located in the culture medium, but a hydrophobic form of the CSPG was extracted from the cell layer. Mesangial cells in the growing phase synthesized and secreted all three types of proteoglycans, but in cells arrested in G0 by serum deprivation the incorporation of (35S)sulfate in CSPG was drastically reduced. In the same cells stimulated to proliferate by replacing the medium with one containing serum, the synthesis of CSPG dramatically enhanced. The synthesis of CSPG and DSPG was also elevated in cells cocultured with cytokines but in contrast was significantly reduced when cultured in medium containing hyperglycemic levels of glucose. Finally, preliminary experiments are reported that indicate that CSPG and DSPG bind to low-density lipoproteins in vitro. These observations suggest a possible specialized function for proteoglycans in cellular processes characteristic of glomerular disease.


1992 ◽  
Vol 2 (10) ◽  
pp. S95
Author(s):  
F Pugliese ◽  
G A Cinotti ◽  
P Menè

We evaluated the importance of the net charge of polyionic macromolecules in the regulation of cultured human mesangial cell growth. Structurally unrelated polyanionic compounds, i.e., heparin, suramin, poly-L-aspartic acid, and poly-L-glutamic acid, strongly inhibited 10% fetal bovine serum-stimulated cell proliferation. On the other hand, two polycations, protamin sulfate and poly-L-lysine, were equally effective in inhibiting cell growth. The antiproliferative activity of each compound was neutralized by molecules with opposite net charge. These data indicate that both anionic and cationic macromolecules exert an antimitogenic effect on cultured human mesangial cells. This inhibitory effect is dependent upon charge density rather than on the net electric charge of each compound.


1999 ◽  
Vol 10 (12) ◽  
pp. 2495-2502 ◽  
Author(s):  
MASAKAZU KOHNO ◽  
KENICHI YASUNARI ◽  
MIEKO MINAMI ◽  
HIROAKI KANO ◽  
KENSAKU MAEDA ◽  
...  

Abstract. This study sought to determine whether platelet-derived growth factor (PDGF) and angiotensin II (AngII) stimulate migration of cultured rat glomerular mesangial cells. After finding that this was so, the effects of adrenomedullin (ADM) and cAMP-elevating agents on basal and stimulated mesangial cell migration were examined. Two isoforms of PDGF, AB and BB, stimulated migration in a concentration-dependent manner between 1 and 50 ng/ml, while the AA isoform lacked significant effect. AngII modestly but significantly stimulated migration in a concentration-dependent manner between 10-7 and 10-6 mol/L. Rat ADM significantly inhibited the PDGF BB- and AngII-stimulated migration in a concentration-dependent manner between 10-8 and 10-7 mol/L. Inhibition by rat ADM was accompanied by an increase in cellular cAMP. cAMP agonists or inducers such as 8-bromo cAMP, forskolin, and prostaglandin I2 also significantly reduced the stimulated migration. H 89, a protein kinase A (PKA) inhibitor, attenuated the inhibitory effect of ADM, and a calcitonin gene-related peptide (CGRP) receptor antagonist, human CGRP (8-37), abolished the inhibitory effects of rat ADM. These results suggest that PDGF AB and BB as well as AngII stimulate rat mesangial cell migration and that ADM can inhibit PDGF BB- and AngII-stimulated migration, at least in part through cAMP-dependent mechanisms likely to involve specific ADM receptors with which CGRP interacts. The adenylate cyclase/cAMP/PKA system may be involved in the migration-inhibitory effect of ADM in these cells.


1983 ◽  
Vol 244 (2) ◽  
pp. F95-F104 ◽  
Author(s):  
L. D. Dworkin ◽  
I. Ichikawa ◽  
B. M. Brenner

Glomeruli contain receptors for many hormones. Binding of angiotensin II (ANG II) or antidiuretic hormone (ADH) to glomerular mesangial cells elicits a contractile response. Other hormones induce synthesis of cyclic nucleotides (cAMP, cGMP). Glomeruli also synthesize several prostaglandins, renin, and ANG II. Micropuncture studies in Munich-Wistar rats have examined the effects of vasoactive drugs and hormones on the filtration process. Several vasodilators increase renal plasma flow in the dog and rat, but GFR remains relatively unchanged due to an offsetting fall in the ultrafiltration coefficient (Kf). Vasoconstrictor substances such as ANG II and norepinephrine cause declines in renal plasma flow and Kf, but GFR remains constant due to an increase in the transcapillary hydraulic pressure gradient. Antidiuretic peptides and parathyroid hormone also reduce Kf. Glomerular mesangial cells may regulate Kf by contracting and reducing glomerular capillary surface area. ANG II and ADH directly stimulate mesangial cell contraction in vitro. Other hormones appear to cause contraction by inducing local ANG II synthesis. These hormonal pathways are implicated in the pathogenesis of altered glomerular function in diverse forms of renal injury.


2001 ◽  
Vol 280 (5) ◽  
pp. F851-F859 ◽  
Author(s):  
Satoko Hanada ◽  
Yoshio Terada ◽  
Seiji Inoshita ◽  
Sei Sasaki ◽  
Suzanne M. Lohmann ◽  
...  

The cGMP-cGMP-dependent protein kinase (protein kinase G) system plays an important role in the pathogenesis of mesangial proliferative glomerulonephritis. However, the molecular mechanisms of the inhibitory effects of the cGMP-protein kinase G system in the cell cycle progression of mesangial cells are not well known. To determine the inhibitory pathway of cGMP-protein kinase G in cultured mesangial cells, we investigated the effects of cGMP- and adenovirus-mediated overexpression of protein kinase G on the promoter activities of cyclin E, cyclin D1, and cyclin A. 8-Bromo-cGMP (8-BrcGMP) and overexpression of protein kinase G reduced [3H]thymidine uptake, reduced the numbers of cells in S and G2/M phases, and decreased the phosphorylation of retinoblastoma (Rb) protein. 8-BrcGMP (10−3 M), protein kinase G adenovirus (Ad-cGKIβ; 1010 plaque-forming units/ml), atrial natriuretic peptide (ANP), and C-type natriuretic peptide (CNP) inhibited the promoter activity of cyclin E to 49, 57, 77, and 78%, respectively. On the other hand, the promoter activities of cyclin D1 and cyclin A were not changed significantly. In Western blot analysis, 8-BrcGMP, Ad-cGKIβ, ANP, and CNP also inhibited cyclin E protein expression dose and time dependently. The p44/p42 mitogen-activated protein kinase (MAPK) kinase 1-p44/p42 MAPK had no effect on cyclin E promoter activities, and the cGMP-protein kinase G pathway did not change MAPK activity. In conclusion, our findings suggest that the reduction of the cyclin E promoter activity that downregulates G1/S transition plays a dominant role in the cGMP- and protein kinase G-induced inhibition of mesangial cell proliferation.


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