The role of homocysteine in the development of glomerulosclerosis : stimulation of monocyte chemoattractant protein-1 in rat mesangial cells

2002 ◽  
Author(s):  
Tsoek-yee, Giselle Cheung
2002 ◽  
Vol 13 (4) ◽  
pp. 894-902 ◽  
Author(s):  
Hunjoo Ha ◽  
Mi Ra Yu ◽  
Yoon Jin Choi ◽  
Masanori Kitamura ◽  
Hi Bahl Lee

ABSTRACT. Although high glucose (HG) has been shown to induce nuclear factor-κB (NF-κB) activation in vascular cells, the upstream regulation and the biologic significance of NF-κB activation in diabetic renal injury are not clear. It was, therefore, examined if HG-induced generation of reactive oxygen species (ROS) and protein kinase C (PKC) activation are involved in NF-κB activation in mesangial cells (MC), and the role of NF-κB activation in HG-induced monocyte chemoattractant protein-1 (MCP-1) expression by MC was further investigated. Recent observations suggest that MCP-1 may play a role in the development and progression of diabetic nephropathy. HG rapidly induced NF-κB activation in MC as estimated by electrophoretic mobility shift assay. Supershift assay suggests that most of the binding activity arose from p50/p50 and p50/p65 dimers. Antioxidants, pyrrolidine dithiocarbamate, n-acetyl-l-cystein, and trolox effectively inhibited HG-induced NF-κB activation in MC. HG rapidly generated dichlorofluorescin-sensitive intracellular ROS in MC as measured by laser-scanning confocal microscopy. HG also activated PKC rapidly in MC. Inhibition of PKC effectively blocked HG-induced intracellular ROS generation and NF-κB activation in MC. HG increased MCP-1 mRNA expression by 1.9-fold and protein secretion by 1.6-fold that of control glucose in MC transfected with control vector but not in MC transfected with dominant negative mutant inhibitor of NF-κB (IκBαM). Inhibition of either PKC or ROS effectively blocked HG-induced, but not basal, MCP-1 protein secretion by MC transfected with control vector. Thus this study demonstrates that HG rapidly activates NF-κB in MC through PKC and ROS and suggests that HG-induced NF-κB activation in MC may play a role in diabetic renal injury through upregulation of MCP-1 mRNA and protein expression.


2008 ◽  
Vol 86 (3) ◽  
pp. 88-96 ◽  
Author(s):  
Giselle T.Y. Cheung ◽  
Yaw L. Siow ◽  
Karmin O

Hyperhomocysteinemia is regarded as an independent risk factor for cardiovascular disorders. Although renal dysfunction or failure is one of the important factors causing hyperhomocysteinemia, the role of homocysteine (Hcy) in the development of glomerulosclerosis is largely unknown. One of the key events in the pathogenesis of glomerulosclerosis is the infiltration of circulating monocytes into affected glomeruli. The objective of the present study was to investigate the effect of Hcy on the expression of monocyte chemoattractant protein-1 (MCP-1) in kidney mesangial cells and the mechanisms involved. Levels of MCP-1 and mRNA were significantly elevated in Hcy-treated rat mesangial cells. This increase was associated with activation of NF-κB as a result of increased phosphorylation of the inhibitor protein IκBα. Monocyte chemotactic activity in these cells was also enhanced. In addition, there was a significant elevation of superoxide anion produced by Hcy-treated cells, which preceded the increased phosphorylation of IκBα. Addition of superoxide dismutase or NF-κB inhibitors to the culture medium abolished Hcy-induced NF-κB activation and MCP-1 expression. Taken together, these results indicate that Hcy induced MCP-1 expression in mesangial cells. Such a process was mediated by oxidative stress and NF-κB activation. This may further aggravate renal function in patients with hyperhomocysteinemia.


Stroke ◽  
2021 ◽  
Vol 52 (Suppl_1) ◽  
Author(s):  
Marios K Georgakis ◽  
Sander W van der Laan ◽  
Yaw Asare ◽  
Joost M Mekke ◽  
Saskia Haitjema ◽  
...  

Background: Monocyte chemoattractant protein-1 (MCP-1) is a chemokine recruiting monocytes to the atherosclerotic plaque. Experimental, genetic, and epidemiological data support a key role of MCP-1 in atherosclerosis. Yet, the translational potential of targeting MCP-1 signaling for lowering vascular risk is limited by the lack of data on plaque MCP-1 activity in human atherosclerosis. Methods: We measured MCP-1 levels in human plaque samples from 1,199 patients undergoing carotid endarterectomy from the Athero-Express Biobank. We explored associations of plaque MCP-1 levels with histopathological features of plaque vulnerability, clinical plaque instability (symptomatic vs. asymptomatic plaque), molecular markers of plaque inflammation and remodeling, and with incident vascular events up to three years after plaque removal. Results: MCP-1 plaque levels were associated with individual histopathological hallmarks of plaque vulnerability (large lipid core, low collagen, high macrophage burden, low smooth muscle cell burden, intraplaque hemorrhage), as well as with a cumulative vulnerability index (range 0-5, beta: 0.42, 95%CI: 0.30-0.53, p=5.4x10 -13 ) independently of age, sex, and conventional vascular risk factors. Furthermore, MCP-1 levels were higher among patients with symptomatic, as compared to asymptomatic plaques (p=0.0001) and were associated with the levels of pro-inflammatory cytokines involved in leukocyte adhesion, as well as with matrix metalloproteinase activity in the plaque. In the follow-up analyses, MCP-1 levels were associated with a higher risk of peri-procedural events (up to 30 days after surgery). Conclusions: Our findings highlight a role of MCP-1 in human plaque vulnerability, the leading mechanism underlying vascular events like stroke and myocardial infarction. As such, they suggest that interfering with MCP-1 signaling in patients with established atherosclerosis could lower vascular risk.


2001 ◽  
Vol 12 (8) ◽  
pp. 1659-1667
Author(s):  
BRAD H. ROVIN ◽  
LING LU ◽  
ANNA COSIO

Abstract. In the kidney an uncontrolled inflammatory response to an acute insult may lead to chronic inflammation, permanent tissue damage, and progressive renal insufficiency. Resolution of acute inflammation likely is dependent on endogenous regulatory mechanisms activated in parallel with mediators of renal inflammation. These mechanisms are postulated to attenuate the renal expression of proinflammatory cytokines, including the chemokines responsible for recruiting leukocytes to the kidney, thus facilitating the transition from inflammation to healing. To understand the regulation of the inflammatory response within the kidney, the effects of anti-inflammatory J series cyclopentenone prostaglandins on chemokine production by human mesangial cells were examined. Treatment of mesangial cells with prostaglandin J2and 15-deoxy-Δ12,14-prostaglandin J2blocked interleukin-1β—induced monocyte chemoattractant protein-1 mRNA expression and protein production. This correlated with failure of the transcription factor nuclear factor-κB (NF-κB) to translocate to the nucleus and bind to its recognition motif, a step required for cytokine-induced monocyte chemoattractant protein-1 gene activation. NF-κB failed to translocate because the cyclopentenone prostaglandins attenuated degradation of the NF-κB inhibitor IκB-α. These data suggest that certain prostaglandins can limit the extent of renal chemokine expression and thus may have an important role in resolving renal inflammation.


2019 ◽  
Vol 17 (6) ◽  
pp. 538-547 ◽  
Author(s):  
Bridie S. Mulholland ◽  
Mark R. Forwood ◽  
Nigel A. Morrison

Abstract Purpose of Review The purpose of this review is to explore the role of monocyte chemoattractant protein-1 (MCP-1 or CCL2) in the processes that underpin bone remodelling, particularly the action of osteoblasts and osteoclasts, and its role in the development and metastasis of cancers that target the bone. Recent Findings MCP-1 is a key mediator of osteoclastogenesis, being the highest induced gene during intermittent treatment with parathyroid hormone (iPTH), but also regulates catabolic effects of continuous PTH on bone including monocyte and macrophage recruitment, osteoclast formation and bone resorption. In concert with PTH-related protein (PTHrP), MCP-1 mediates the interaction between tumour-derived factors and host-derived chemokines to promote skeletal metastasis. In breast and prostate cancers, an osteolytic cascade is driven by tumour cell–derived PTHrP that upregulates MCP-1 in osteoblastic cells. This relationship between PTHrP and osteoblastic expression of MCP-1 may drive the colonisation of disseminated breast cancer cells in the bone. Summary There is mounting evidence to suggest a pivotal role of MCP-1 in many diseases and an important role in the establishment of comorbidities. Coupled with its role in bone remodelling and the regulation of bone turnover, there is the potential for pathological relationships between bone disorders and bone-related cancers driven by MCP-1. MCP-1’s role in bone remodelling and bone-related cancers highlights its potential as a novel anti-resorptive and anti-metastatic target.


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