Poria cocosInhibits High Glucose-Induced Proliferation of Rat Mesangial Cells

2013 ◽  
Vol 41 (01) ◽  
pp. 71-83 ◽  
Author(s):  
Jung Joo Yoon ◽  
Yun Jung Lee ◽  
So Min Lee ◽  
Song Nan Jin ◽  
Dae Gill Kang ◽  
...  

Mesangial cell proliferation is correlated with the progression of renal failure. The purpose of this study was to determine whether a water extract of Poria cocos Wolf (WPC), a well-known medicinal plant, regulates rat mesangial cell proliferation in the presence of high glucose (HG). HG significantly accelerated [3H]-thymidine incorporation, which was inhibited by WPC (1–50 μg/mL) in a dose-dependent manner. Cell migration and fibronectin mRNA expression data also supported the anti-proliferative effect of WPC. Western blot analysis revealed that pretreatment with WPC decreased the expression of cyclins and cyclin-dependent kinases (CDKs) and promoted the expression of p21waf1/cip1and p27kip1. WPC also suppressed HG-induced p38 mitogen-activated protein kinase (p38 MAPK) and extracellular-signal-regulated kinase 1/2 (ERK 1/2) phosphorylation. Furthermore, WPC inhibited HG-induced production of dichlorofluorescein (DCF)-sensitive intracellular reactive oxygen species (ROS). In conclusion, HG promoted mesangial cell proliferation, and WPC inhibited this activity, at least in part, via induction of cell cycle arrest and activation of anti-oxidant properties. Taken together, these results suggest that P. cocos may be a potent regulator of HG-induced proliferation.

1998 ◽  
Vol 9 (3) ◽  
pp. 488-496
Author(s):  
B V Bassa ◽  
D D Roh ◽  
M A Kirschenbaum ◽  
V S Kamanna

Previously, it has been shown that atherogenic lipoproteins, through the activation of glomerular cells, stimulate pathobiological processes involved in monocyte infiltration into the mesangium. This study examined the role of LDL and its oxidatively modified variants (mildly oxidatively modified LDL [mm-LDL] and oxidatively modified LDL [ox-LDL]) on the activation of mesangial cell p42 mitogen-activated protein kinase (MAP kinase), a key intracellular signaling mechanism associated with cell proliferation. The incubation of mesangial cells with either LDL, mm-LDL, or ox-LDL induced the activation of MAP kinase dose dependently. The activation of MAP kinase by these lipoproteins in mesangial cells occurred biphasically: initially at 15 min of incubation period and at later time points of 8 to 24 h. No activation of MAP kinase was noted between 30 min (except in LDL) and 6 h. The induction of MAP kinase by both mm-LDL and ox-LDL was greater by 1.5- to 2-fold when compared with LDL. Similarly, these atherogenic lipoproteins stimulated mesangial cell proliferation. Lysophosphatidylcholine, a component of both oxidatively modified variants of LDL, markedly stimulated mesangial cell MAP kinase activity at early incubation times (5 to 30 min) but not at later time points (3 to 24 h), suggesting that lysophosphatidylcholine may, at least in part but not solely, act as an active component of ox-LDL-mediated effects. These data define putative key signal transduction events associated with lipoprotein-mediated induction of mesangial cell proliferation.


1997 ◽  
Vol 273 (6) ◽  
pp. F916-F924 ◽  
Author(s):  
Ayad A. Jaffa ◽  
Bradley S. Miller ◽  
Steven A. Rosenzweig ◽  
Padma S. Naidu ◽  
Victoria Velarde ◽  
...  

Glomerular hypertension and glomerular hypertrophy act early and synergistically to promote glomerular injury in diabetes. We have previously shown that increased renal kinin production contributes to the glomerular hemodynamic abnormalities associated with diabetes. Glomerulosclerosis, characterized by mesangial cell proliferation and matrix expansion, is the final pathway leading to renal failure. The signal(s) initiating mesangial cell proliferation is ill defined. In the present study, we utilized immunofluorescence, immunoprecipitation, and immunoblotting techniques to identify substrates that are tyrosine phosphorylated in response to bradykinin action in mesangial cells. Immunofluorescence microscopy of mesangial cells stained with anti-phosphotyrosine (anti-PY) antibodies following bradykinin treatment (10−9–10−6M) revealed a dose-dependent increase in the labeling of cytoplasmic and nuclear proteins. Immunoprecipitation with anti-PY, followed by immunoblot revealed bradykinin-induced tyrosyl phosphorylation of tubulin and mitogen-activated protein kinase (MAPK). Confocal microscopy of mesangial cells stained for MAPK indicated that bradykinin stimulation resulted in translocation of MAPK from the cytoplasm to the nucleus by 2 h. These data demonstrate that bradykinin action results in the tyrosine phosphorylation of cellular proteins in mesangial cells and suggest a role for tubulin and MAPK in the signaling cascade of bradykinin leading to altered mesangial function.


2020 ◽  
Vol 21 (19) ◽  
pp. 7003
Author(s):  
Jung Joo Yoon ◽  
Hyeon Kyoung Lee ◽  
Hye Yoom Kim ◽  
Byung Hyuk Han ◽  
Ho Sub Lee ◽  
...  

Abnormal and excessive growth of mesangial cells is important in the pathophysiologic processes of diabetes-associated interstitial fibrosis and glomerulosclerosis, leading to diabetic nephropathy, which eventually turns into end-stage renal disease. Sauchinone, a biologically-active lignan isolated from aerial parts of Saururus chinensis, has anti-inflammatory and anti-viral activities effects on various cell types. However, there are no studies reporting the effects of sauchinone on diabetic nephropathy. The present study aims to investigate the role of sauchinone in mesangial cell proliferation and fibrosis induced by angiotensin II, as well as the underlying mechanisms of these processes. Human renal mesangial cells were induced by angiotensin II (AngII, 10 μM) in the presence or absence of sauchinone (0.1–1 μM) and incubated for 48 h. In this study, we found that AngII induced mesangial cell proliferation, while treatment with sauchinone inhibited the cell proliferation in a dose-dependent manner. Pre-treatment with sauchinone induced down-regulation of cyclins/CDKs and up-regulation of CDK inhibitor, p21, and p27kip1 expression. In addition, AngII-enhanced expression of fibrosis biomarkers such as fibronectin, collagen IV, and connective tissue growth factor (CTGF), which was markedly attenuated by sauchinone. Sauchinone also decreased AngII-induced TGF-β1 and Smad-2, Smad-3, and Smad-4 expression. This study further revealed that sauchinone ameliorated AngII-induced mesangial inflammation through disturbing activation of inflammatory factors, and NLRP3 inflammasome, which is composed of the NLRP3 protein, procaspase-1, and apoptosis-associated speck-like protein containing a CARD (ASC). Moreover, pretreatment of sauchinone inhibited NF-κB translocation and ROS production in AngII-exposed mesangial cells. These data suggest that sauchinone has a protective effect on renal proliferation, fibrosis and inflammation. Therefore, sauchinone might be a potential pharmacological agent in prevention of AngII-induced renal damage leading to diabetic nephropathy.


2014 ◽  
Vol 2014 ◽  
pp. 1-14 ◽  
Author(s):  
Chuan Lv ◽  
Can Wu ◽  
Yue-hong Zhou ◽  
Ying Shao ◽  
Guan Wang ◽  
...  

The aim of this study was to investigate whether alpha lipoic acid (LA) regulates high glucose-induced mesangial cell proliferation and extracellular matrix production via mTOR/p70S6K/4E-BP1 signaling. The effect of LA on high glucose-induced cell proliferation, fibronectin (FN), and collagen type I (collagen-I) expression and its mechanisms were examined in cultured rat mesangial cells by methylthiazol tetrazolium (MTT) assay, flow cytometry, ELISA assay, and western blot, respectively. LA at a relatively low concentration (0.25 mmol/L) acted as a growth factor in rat mesangial cells, promoted entry of cell cycle into S phase, extracellular matrix formation, and phosphorylated AKT, mTOR, p70S6K, and 4E-BP1. These effects disappeared when AKT expression was downregulated with PI3K/AKT inhibitor LY294002. Conversely, LA at a higher concentration (1.0 mmol/L) inhibited high glucose-induced rat mesangial cell proliferation, entry of cell cycle into S phase, and extracellular matrix exertion, as well as phosphorylation of mTOR, p70S6K, and 4E-BP1 but enhanced the activity of AMPK. However, these effects disappeared when AMPK activity was inhibited with CaMKK inhibitor STO-609. These results suggest that LA dose-dependently regulates mesangial cell proliferation and matrix protein secretion by mTOR/p70S6K/4E-BP1 signaling pathway under high glucose conditions.


2002 ◽  
Vol 283 (2) ◽  
pp. F271-F279 ◽  
Author(s):  
Platina E. Coy ◽  
Navin Taneja ◽  
Iris Lee ◽  
Claudie Hecquet ◽  
Jane M. Bryson ◽  
...  

The prototypical extracellular phospholipid mediator, lysophosphatidic acid (LPA), exhibits growth factor-like properties and represents an important survival factor in serum. This potent mesangial cell mitogen is increased in conditions associated with glomerular injury. It is also a known activator of the classic mitogen-activated protein kinase (MAPK) pathway, which plays an important role in the regulation of mesangial cell hexokinase (HK) activity. To better understand the mechanisms coupling metabolism to injury, we examined the ability of LPA to regulate HK activity and expression in cultured murine mesangial cells. LPA increased total HK activity in a concentration- and time-dependent manner, with maximal increases of >50% observed within 12 h of exposure to LPA concentrations ≥25 μM (apparent ED50 2 μM). These effects were associated with increased extracellular signal-regulated kinase (ERK) activity and were prevented by the pharmacological inhibition of either MAPK/ERK kinase or protein kinase C (PKC). Increased HK activity was also associated with increased glucose (Glc) utilization and lactate accumulation, as well as selectively increased HKII isoform abundance. The ability of exogenous LPA to increase HK activity was both Ca2+independent and pertussis toxin insensitive and was mimicked by LPA-generating phospholipase A2. We conclude that LPA constitutes a novel lipid regulator of mesangial cell HK activity and Glc metabolism. This regulation requires sequential activation of both Ca2+-independent PKC and the classic MAPK pathway and culminates in increased HKII abundance. These previously unrecognized metabolic consequences of LPA stimulation have both physiological and pathophysiological implications. They also suggest a novel mechanism whereby metabolism may be coupled to cellular injury via extracellular lipid mediators.


2007 ◽  
Vol 292 (1) ◽  
pp. F76-F81 ◽  
Author(s):  
Helen R. Lock ◽  
Steven H. Sacks ◽  
Michael G. Robson

In view of its proven antiproliferative effects, rapamycin offers potential in the treatment of mesangioproliferative disease. Previous data have shown an effect of rapamycin on mesangial cell proliferation at high doses and have not explored the mechanism of action. Therefore, we explored the effects and mechanism of action of low levels of rapamycin on mesangial cell proliferation. Primary cultures of mouse mesangial cells were grown in medium containing serum with differing concentrations of rapamycin. A rapamycin concentration of 0.1 ng/ml caused a decrease in cell number and DNA synthesis with no effect on apoptosis. Type IV collagen protein production was inhibited at 0.01 ng/ml rapamycin, although gene expression was unaffected. P70S6K phosphorylation was inhibited in parallel with the effects on cell number and DNA synthesis in a dose-dependent manner, but no effect was seen at 0.01 ng/ml rapamycin. These data show an effect on mesangial cell proliferation and p70S6 kinase phosphorylation of 0.1 ng/ml rapamycin and an effect on collagen IV production of 0.01 ng/ml rapamycin. We suggest that further in vivo studies should explore the potential for low-dose rapamycin in the treatment of mesangioproliferative glomerulonephritis.


2000 ◽  
Vol 279 (4) ◽  
pp. F688-F697 ◽  
Author(s):  
J. A. Dlugosz ◽  
S. Munk ◽  
J. Kapor-Drezgic ◽  
H. J. Goldberg ◽  
I. G. Fantus ◽  
...  

Glomerular hypertension and hyperglycemia are major determinants of diabetic nephropathy. We sought to identify the mechanisms whereby stretch-induced activation of mesangial cell extracellular signal-regulated kinase 1 and 2 (ERK1/ERK2) is enhanced in high glucose (HG). Mesangial cells cultured on fibronectin Flex I plates in normal glucose (NG; 5.6 mM) or HG (30 mM), were stretched by 15% elongation at 60 cycles/min for up to 60 min. In HG, a 5-min stretch increased ERK1/ERK2 phosphorylation by 6.4 ± 0.4/4.3 ± 0.3-fold ( P < 0.05 vs. NG stretch). In constrast, p38 phosphorylation was increased identically by stretch in NG and HG. Unlike many effects of HG, augmentation of ERK activity by HG was not dependent on protein kinase C (PKC) as indicated by downregulation of PKC with 24-h phorbol ester or inhibition with bisindolylmaleimide IV. In both NG and HG, pretreatment with arginine-glycine-aspartic acid peptide (0.5 mg/ml) to inhibit integrin binding or with cytochalasin D (100 ng/ml) to disassemble filamentous (F) actin, significantly reduced phosphorylation of ERK1/ERK2 and p38. To determine whether the rate of mitogen-activated protein kinase dephosphorylation is affected by HG, cellular kinase activity was inhibited by depleting ATP. Post-ATP depletion, phosphorylation of ERK1/ERK2 was reduced to 36 ± 9/51 ± 14% vs. 9 ± 5/7 ± 6% in NG ( P < 0.05, n = 5). Thus stretch-induced ERK1/ERK2 and p38 activation in both NG and HG is β1-integrin and F-actin dependent. Stretch-induced ERK1/ERK2 is enhanced in high glucose by diminished dephosphorylation, suggesting reduced phosphatase activity in the diabetic milieu. Enhanced mesangial cell ERK1/ERK2 signaling in response to the combined effects of mechanical stretch and HG may contribute to the pathogenesis of diabetic nephropathy.


2015 ◽  
Vol 12 (2) ◽  
pp. 2643-2649 ◽  
Author(s):  
XIAOSHUANG ZHOU ◽  
CHEN WANG ◽  
JIHUA TIAN ◽  
YANHONG WANG ◽  
YAFENG LI ◽  
...  

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