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ABSTRACT: The present study aimed to investigate the effects of Cordyceps sinensis on renal fibrosis and its possible mechanisms. Sprague-Dawley rats were randomly divided into three groups: sham operation (SHAM) group, 5/6 subtotal nephrectomy (SNx) untreated group, and 5/6 subtotal nephrectomy treated with Cordyceps sinensis (2.0g/kg.d) (CS) group. Rats were studied 12 weeks after the surgery, and the CS group presented with significantly lower proteinuria, and better renal function compared with the SNx group (p<0.05). Pathological study showed that the glomerulosclerosis tubulointerstitial injury score was significantly reduced in the CS group compared with the SNx group. Furthermore, the mRNA expression of TGF-β1, Smad2 and Smad3 and the protein expression of TGF-β1, TβRI, TβRII and p-Smad2/3 were attenuated by the Cordyceps sinensis treatment. In constrast, the mRNA and protein expression of Smad7 was upregulated. Furthermore, the expression of α-SMA and FSP1 was also significantly attenuated, accompanied by the increasing expression of E-cadherin, suggesting the inhibition of the epithelial-mesenchymal transition (EMT). In conclusion: Cordyceps sinensis exerted its antifibrotic effect on the SNx rats through the inhibition of the TGF-β1/Smad pathway.
Food and chemical toxicology: an international journal published for the British Industrial Biological Research Association 04/2013; · 2.99 Impact Factor
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ABSTRACT: BACKGROUND: Dyslipidemia and activation of renin-angiotensin system (RAS) contribute to the progression of chronic kidney disease (CKD). This study investigated possible synergistic effects of intrarenal RAS activation with hyperlipidemia in renal injuries. METHODS: Apolipoprotein knockout mice were fed with normal chow diet (control) or high fat diet (HF group) for eight weeks. Human proximal tubular epithelial cell line (HK-2) was treated without (control) or with cholesterol (30 mug/ml) plus 25-hydroxycholesterol (1 mug/ml) (lipid group) for 24 hours. The plasma lipid profile and RAS components were determined by clinical biochemistry assay and radiommunoassay, respectively. Collagen deposition in kidneys was evaluated by Masson-staining. The gene and protein expressions of molecules involved in RAS components and biomarkers of epithelial mesenchymal transition (EMT) were examined by real-time PCR, immunochemical staining, and Western blot. RESULTS: The mice fed with high-fat diet showed significant hyperlipidemia with collagen deposition in renal tubular interstitium compared to controls. The plasma levels of renin, angiotensin I, and angiotensin II were no difference in two groups. However, the kidneys of HF group showed up-regulated RAS components, which were positively associated with increased plasma levels of triglyceride, total cholesterol, and LDL. These effects were further confirmed by in vitro studies. Lipid loading induced HK-2 cells underwent EMT, which was closely associated with the increased expressions of intracellular RAS components. CONCLUSIONS: Local RAS activation was involved in hyperlipidemia-mediated renal injuries, suggesting that there are synergistic effects resulting from RAS activation with hyperlipidemia that accelerates the progression of CKD.
Lipids in Health and Disease 04/2013; 12(1):49. · 2.17 Impact Factor
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ABSTRACT: Chronic inflammation plays a crucial role in the progression of cardiac fibrosis. This study investigated whether inflammation exacerbated the progression of cardiac fibrosis in high-fat-fed apolipoprotein E knockout (ApoE KO) mice via endothelial-mesenchymal transition (EndMT). Twenty-four male ApoE KO mice were divided into normal chow diet (Control), high-fat diet (HFD), or high-fat diet plus 10% casein injection (inflamed) groups for 8 weeks. The body weight of ApoE KO mice was measured at each week. The lipid profile and serum amyloid A (SAA) levels were examined using clinical biochemistry and enzyme-linked immunosorbent assays, respectively. Cardiac lipid and collagen accumulation was visualised with haematoxylin-eosin (HE) and Masson's trichrome staining. EndMT-related molecule expression was examined by immunohistochemistry and Western blotting. SAA levels were increased in the inflamed group compared with the HFD and control groups, suggesting that inflammation was successfully induced. There were no differences in body weight among three groups at each week. Interestingly, inflammation significantly reduced serum total cholesterol, triglyceride, and low-density lipoprotein (LDL) levels compared with the HFD mice. However, both foam cell formation in cardiac blood vessels and cardiac collagen deposition were increased in the inflamed group, as demonstrated by HE and Masson trichrome staining. Furthermore, inflammation reduced protein expression of CD31 and increased protein expression of alpha-smooth muscle actin (α-SMA) and collagen I, which contribute to cardiac EndMT. Inflammatory stress exacerbates the progression of cardiac fibrosis in high-fat-fed ApoE KO mice via EndMT, suggesting that hyperlipidaemia and inflammation act synergistically to redistribute plasma lipids to cardiac tissues and accelerate the progression of cardiac fibrosis.
International journal of medical sciences 01/2013; 10(4):420-6. · 2.24 Impact Factor
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ABSTRACT: Tubulointerstitial macrophage infiltration is a hallmark of chronic kidney disease (CKD) involved in the progression of renal fibrosis. Pirfenidone is a newly identified anti-fibrotic drug, the potential mechanism of which remains unclear. The aim of this study was to investigate the effects of pirfenidone on M1/M2 macrophage infiltration in nephrectomized rats. Nephrectomized rats were treated with pirfenidone by gavage for 12 weeks. 24-h urinary protein, NAG activity, systolic blood pressure (SBP) and CRP were determined. Paraffin-embedded sections were stained for CD68 (-), CCR7 (-) and CD163 (-) macrophages. MCP-1 and MIP-1α, as well as M1 and M2 macrophages secretory markers were evaluated by real-time RT-PCR and western blotting analysis. Pirfenidone significantly improved the elevated proteinuria and NAG activity from week 2 onward after surgery. Pirfenidone attenuated interstitial fibrosis and decreased expression of fibrotic markers including TGF-β1, CTGF, α-SMA, fibronectin and FSP-1. Pirfenidone significantly decreased the infiltrating macrophages. The number of M1 and M2 macrophages was significantly lower after pirfenidone treatment. MCP-1 and MIP-1α were increased in nephrectomized rats at mRNA and protein levels. Pirfenidone treatment significantly inhibited their expression. The TNF-α, IL-6 and iNOS expressed by M1 macrophages were increased in nephrectomized rats, and pirfenidone significantly attenuated their expression. Pirfenidone treatment also significantly decreased arginase-1, dectin-1, CD206 and CD86 expressed by M2 macrophages. Thus, Pirfenidone inhibits M1 and M2 macrophage infiltration in 5/6 nephrectomized rats, which suggests its efficacy in the early and late periods of renal fibrosis.
AJP Renal Physiology 11/2012; · 4.42 Impact Factor
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Long Chen,
Yong-Gui Wu,
Dan Liu,
Lin-Li Lv,
Min Zheng,
Hai-Feng Ni,
Yu-Han Cao,
Hong Liu,
Pei Zhang,
Jian-Dong Zhang, Bi-Cheng Liu
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ABSTRACT: Background: We investigated whether urinary mRNA of connective tissue growth factor (CCN2) and nephroblastoma overexpressed gene (CCN3) can provide clinical insight into the management of patients with nondiabetic CKD. Methods: Urinary mRNA expression of CCN2 and CCN3 were measured by Real-time PCR in 35 CKD patients and 12 controls. Results: Urinary mRNA of CCN2 and CCN3 were distinctively greater in CKDs than healthy controls. Urinary CCN3/CCN2 mRNA ratio correlated to the degree of glomerular histological changes in those who received renal biopsy. Conclusion: Urinary CCN3/CCN2 mRNA ratio may be a useful noninvasive biomarker for evaluating patients with nondiabetic CKD prior to renal biopsy.
Biomarkers 10/2012; · 2.21 Impact Factor
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ABSTRACT: Epithelial-mesenchymal transition (EMT) is a key cellular event in the early stage of tubulointerstitial fibrosis (TIF). Monocyte infiltration plays an important role in the progression of TIF. We have previously demonstrated that monocytes can directly induce HK-2 cell transition by direct contact. Dexamethasone, an important anti-inflammatory and immunosuppressant agent, has been widely used in renal disease for decades. Whether it could influence the monocyte and HK-2 cell interaction and prevent EMT is still uncertain. In this study we found that the typical epithelial cell morphology of HK-2 cells disappeared 24 hours after co-culture with monocytes, and dexamethasone significantly prevented this change in a dose-dependent manner. In addition, we found that dexamethasone prevented monocytes from binding to HK-2 cells by inhibiting ICAM-1 expression on HK-2 cells. Further analysis demonstrated that there was increased E-cadherin expression and decreased α-SMA and fibronectin expression after co-culture with dexamethasone, suggesting that dexamethasone prevents monocyte-induced HK-2 cell transition. The nuclear transcription factor κB (NF-κB) pathway played an important role in this process. These findings suggest a novel mechanism by which corticosteroids may delay the progression of TIF via preventing EMT. J. Cell. Biochem. © 2012 Wiley Periodicals, Inc.
Journal of Cellular Biochemistry 10/2012; · 2.87 Impact Factor
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ABSTRACT: INTRODUCTION:: Left ventricular hypertrophy (LVH) is a major cardiovascular complication and an important predictor of mortality in patients with end-stage renal disease. Angiotensin II blockades have been widely used in the treatment of hypertension; however, the influence of angiotensin receptor blockers (ARBs) on LVH in dialysis patients has not been thoroughly studied. In this meta-analysis, the authors analyzed the effect of ARBs on LVH and left ventricular function in patients on maintenance dialysis. METHODS:: The authors did systematic search of PubMed, Embase and Cochrane Central Register of Controlled Trials, until November 2010. Data extracted from the literature were analyzed with the Review Manager. RESULTS:: The results of 6 randomized controlled trials (207 participants) reveal that ARB group had a greater regression of left ventricular mass index (LVMi) when compared with non-ARB group (P = 0.002) in dialysis patients while no significant difference for left ventricular ejection fraction (LVEF; P = 0.30). The ARB group had a nonsignificantly greater therapeutic value of LVMi or LVEF when compared with angiotensin-converting enzyme inhibitor (ACEI; P = 0.74 and 0.49, respectively). No significant alterations were observed in LVMi and LVEF between the combination of ARBs and ACEIs and ARBs group (P = 0.43 and 0.24, respectively). CONCLUSIONS:: ARBs are associated with a greater reduction in LVH in patients on dialysis. The ARB therapy tends to have a similar favorable effectiveness as ACEI; however, the combination of ARBs with ACEIs did not show additional benefit to LVH in patients on hemodialysis.
The American Journal of the Medical Sciences 09/2012; · 1.39 Impact Factor
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ABSTRACT: Chronic kidney disease (CKD) is a major public health problem that affects about 10% of the general population. Current approaches to characterize the category and progression of CKD are normally based on renal histopathological results and clinical parameters. However, this information is not sufficient to predict CKD progression risk reliably or to guide preventive interventions. Nowadays, the appearance of systems biology has brought forward the concepts of "-omics" technologies, including genomics, transcriptomics, proteomics, and metabolomics. Systems biology, together with molecular analysis approaches such as microarray analysis, genome-wide association studies (GWAS), and serial analysis of gene expression (SAGE), has provided the framework for a comprehensive analysis of renal disease and serves as a starting point for generating novel molecular diagnostic tools for use in nephrology. In particular, analysis of urinary mRNA and protein levels is rapidly evolving as a non-invasive approach for CKD monitoring. All these systems biological molecular approaches are required for application of the concept of "personalized medicine" to progressive CKD, which will result in tailoring therapy for each patient, in contrast to the "one-size-fits-all" therapies currently in use.
Chinese medical journal 07/2012; 125(14):2603-9. · 0.86 Impact Factor
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ABSTRACT: Integrin-linked kinase (ILK) dysregulation is involved in the progression of diabetic nephropathy (DN). The aim of this study was to investigate the effects of angiotensin II receptor blocker (ARB), irbesartan, on ILK expression and podocyte injury in DN.
DN was induced by the combined feeding of high-sucrose, high-fat diet and intra-peritoneal injection of low dose of streptozotocin (35 mg/kg) in spontaneously hypertensive rats. Diabetic rats were treated with irbesartan (50 mg×kg(-1)×d(-1)) by gavage for 8 weeks. The renal morphologic changes and podocyte injury were investigated by light and electron microscopy, and the ILK expression was evaluated by real-time RT-PCR and Western blotting analysis.
Diabetic rats exhibited with the similar clinical feature of type 2 DN. Morphologically, they were characterized by expansion of mesangial matrix, loss of podocyte and podocyte injury. Impressively, compared to controls, the ILK expression in diabetic rats were upregulated, which were positively correlated with both podocyte injury and albuminuria. Irbesartan significantly prevented ILK overexpression, along with the amelioration of podocyte injury and albuminuria.
ILK plays an important role in mediating podocyte injury in DN; irbesartan inhibits ILK upregulation and attenuates podocyte injury, which might offer a new insight into the role of ARB in preventing DN progression.
Chinese medical journal 03/2012; 125(5):888-93. · 0.86 Impact Factor
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ABSTRACT: The non-hemodynamic effects of angiotensin receptor blocker (ARB) in the delay of progression of chronic kidney disease (CKD) remain unclear. In this study, we investigated the influence of irbesartan on the urinary excretion of cytokines in patients with CKD.
In this randomized perspective clinical trial, different doses of irbesartan (150 mg/d and 300 mg/d) were given to two groups of patients in a cross-over design. Blood pressure (BP), creatinine clearance (Ccr) and 24-hour proteinuria were examined. Urinary excretion of cytokines was determined by human inflammatory cytokine antibody array. A two-fold change in spot intensity was considered significant.
Urinary excretion of cytokines (granulocyte colony stimulating factor (GCSF), intercellular cell adhesion molecule-1 (ICAM-1), interferon γ (IFN-γ), interleukin 1β (IL-1b), IL-2, IL-6, IL-8, IL-11, IL-15 and macrophage inflammatory protein 1d (MIP-1d)) in group B (irbesartan 300 mg/d) was significantly decreased in comparison to group A (irbesartan 150 mg/d) after 8-week treatment. In group A, 8 weeks of treatment induced a two- to nine-fold reduction in urinary cytokine levels (GCSF, GM-CSF, IFN-γ, IL-1a, IL-11, IL-12p40, MCP-2, MIP-1a), while increasing the dosage to 300 mg/d further decreased the excretion of GCSF, GM-CSF, IL-12p40, MCP-2 and MIP-1a by week 18. There was no significant difference in BP or Ccr between the two groups. However, 24-hour proteinuria was significantly reduced in both groups, and in group A the reduction was dose dependent.
Irbesartan offers additional renoprotection in a dose-dependent manner by reducing pro-inflammatory cytokines excretion in the urine of CKD patients.
Chinese medical journal 03/2012; 125(6):1147-52. · 0.86 Impact Factor
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ABSTRACT: Chronic inflammation plays a crucial role in the progression of vascular calcification (VC). This study was designed to investigate whether the low-density lipoprotein receptor (LDLr) pathway is involved in the progression of VC in patients with end-stage renal disease (ESRD) during inflammation.
Twenty-eight ESRD patients were divided into control and inflamed groups according to plasma C-reactive protein (CRP) level. Surgically removed tissues from the radial arteries of patients receiving arteriovenostomy were used in the experiments. The expression of tumour necrosis factor-α (TNF-α) and monocyte chemotactic protein-1 (MCP-1) of the radial artery were increased in the inflamed group. Hematoxylin-eosin and alizarin red S staining revealed parallel increases in foam cell formation and calcium deposit formation in continuous cross-sections of radial arteries in the inflamed group compared to the control, which were closely correlated with increased LDLr, sterol regulatory element binding protein-2 (SREBP-2), bone morphogenetic proteins-2 (BMP-2), and collagen I protein expression, as shown by immunohistochemical and immunofluorescent staining. Confocal microscopy confirmed that inflammation enhanced the translocation of the SREBP cleavage-activating protein (SCAP)/SREBP-2 complex from the endoplasmic reticulum to the Golgi, thereby activating LDLr gene transcription. Inflammation increased alkaline phosphatase protein expression and reduced α-smooth muscle actin protein expression, contributing to the conversion of the vascular smooth muscle cells in calcified vessels from the fibroblastic to the osteogenic phenotype; osteogenic cells are the main cellular components involved in VC. Further analysis showed that the inflammation-induced disruption of the LDLr pathway was significantly associated with enhanced BMP-2 and collagen I expression.
Inflammation accelerated the progression of VC in ESRD patients by disrupting the LDLr pathway, which may represent a novel mechanism involved in the progression of both VC and atherosclerosis.
PLoS ONE 01/2012; 7(10):e47217. · 4.09 Impact Factor
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ABSTRACT: The initiation and progression of diabetic nephropathy (DN) is complex. Quantification of mRNA expression in urinary sediment has emerged as a novel strategy for studying renal diseases. Considering the numerous molecules involved in DN development, a high-throughput platform with parallel detection of multiple mRNAs is needed. In this study, we constructed a self-assembling mRNA array to analyze urinary mRNAs in DN patients with aims to reveal its potential in searching novel biomarkers.
mRNA array containing 88 genes were fabricated and its performance was evaluated. A pilot study with 9 subjects including 6 DN patients and 3 normal controls were studied with the array. DN patients were assigned into two groups according to their estimate glomerular rate (eGFR): DNI group (eGFR>60 ml/min/1.73 m(2), n = 3) and DNII group (eGFR<60 ml/min/1.73 m(2), n = 3). Urinary cell pellet was collected from each study participant. Relative abundance of these target mRNAs from urinary pellet was quantified with the array.
The array we fabricated displayed high sensitivity and specificity. Moreover, the Cts of Positive PCR Controls in our experiments were 24±0.5 which indicated high repeatability of the array. A total of 29 mRNAs were significantly increased in DN patients compared with controls (p<0.05). Among these genes, α-actinin4, CDH2, ACE, FAT1, synaptopodin, COL4α, twist, NOTCH3 mRNA expression were 15-fold higher than those in normal controls. In contrast, urinary TIMP-1 mRNA was significantly decreased in DN patients (p<0.05). It was shown that CTGF, MCP-1, PAI-1, ACE, CDH1, CDH2 mRNA varied significantly among the 3 study groups, and their mRNA levels increased with DN progression (p<0.05).
Our pilot study demonstrated that mRNA array might serve as a high-throughput and sensitive tool for detecting mRNA expression in urinary sediment. Thus, this primary study indicated that mRNA array probably could be a useful tool for searching new biomarkers for DN.
PLoS ONE 01/2012; 7(5):e34824. · 4.09 Impact Factor
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ABSTRACT: Emerging evidence has suggested that podocytes undergo epithelial-mesenchymal transition (EMT) in diabetic nephropathy (DN). Connective tissue growth factor (CTGF) and integrin-linked kinase (ILK) are involved in the progression of DN. However, the underlying mechanisms of EMT are not well understood. The study aimed to investigate the roles of CTGF and ILK in high glucose-induced phenotypic alterations of podocytes and determine whether ILK signaling is downstream of CTGF. The epithelial marker of nephrin and the mesenchymal marker of desmin were investigated by real-time RT-PCR and Western blotting. The results demonstrated that podocytes displayed a spreading, arborized morphology in normal glucose, whereas they had a cobblestone morphology in high glucose conditions, accompanied by decreased nephrin expression and increased desmin expression, suggesting podocytes underwent EMT. In response to high glucose, CTGF and ILK expression in podocytes were increased in a dose- and time-dependent manner, whereas the increase did not occur in the osmotic control. Furthermore, the inhibition of CTGF with anti-CTGF antibody prevented the phenotypic transition, as demonstrated by the preservation of epithelial morphology, the suppression of high glucose-induced desmin overexpression and the restoration of nephrin. Of note, the upregulation of ILK induced by high glucose was partially blocked by the inhibition of CTGF. In summary, these findings suggested that CTGF and ILK were involved in high glucose-induced phenotypic alterations of podocytes. ILK acted as a downstream kinase of CTGF and high glucose-induced ILK expression might occur through CTGF-dependent and -independent pathways.
Journal of Cellular Biochemistry 09/2011; 113(1):293-301. · 2.87 Impact Factor
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ABSTRACT: Epithelial-mesenchymal transition (EMT) plays an important role in the pathogenesis and progression of diabetic nephropathy (DN). Quantification of messenger RNA (mRNA) expression in urinary sediment is emerging as a noninvasive method of screening DN-associated biomarkers. The aim of our study was to examine whether urinary mRNA profile of EMT-associated genes may provide valuable clinical insight into the different stages of DN.
Diabetic nephropathy patients (n = 44) and healthy controls (n = 12) were enrolled in this study. DN patients were divided into three groups according to the levels of estimated glomerular filtration rate (eGFR): Group A (eGFR > 60 ml/min per 1·73 m(2), n = 27), Group B (45 < eGFR < 60 ml/min per 1·73 m(2), n = 9), and Group C (eGFR < 45 ml/min per 1·73 m(2), n = 8). Relative mRNA abundance of α-smooth muscle actin (α-SMA), fibronectin, FSP1 and matrix metalloproteinase-9 (MMP-9) were quantified, and correlations between target mRNAs and clinical parameters were examined.
The urinary mRNA levels of α-SMA, fibronectin and MMP-9 were significantly higher in the DN group compared with controls (P < 0·05), and mRNA levels increased with DN progression. Urinary mRNA levels of all target genes positively correlated with both urinary albumin excretion (UAE) and blood urea nitrogen (BUN). Moreover, the expression of α-SMA, fibronectin and MMP-9 mRNA correlated with serum creatinine levels (r = 0·514, r = 0·53 and r = 0·469, all P < 0·001) and GFR levels (r = -0·374, r = -0·392 and r = -0·487, all P < 0·01).
Quantification of EMT-associated genes in urinary sediment may be a novel approach for searching new biomarkers of DN.
Clinical Endocrinology 08/2011; 76(5):657-64. · 3.17 Impact Factor
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ABSTRACT: Recently, a pathogenic glomerulotubular feedback loop was proposed to be a mechanism involving in the transition from acute kidney diseases to chronic status, with highlighting immune cells as a center of this loop. Several important limitations largely reduce its applicable content. Here we amended this proposal by introducing Ang II as a missing node into the paradigm. We believe that better understanding key questions such as interactions between Ang II and immune cells may foster new promising therapeutic options in the prevention of acute-to-chronic transition.
Medical Hypotheses 07/2011; 77(4):595-7. · 1.39 Impact Factor
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ABSTRACT: Patients with chronic kidney disease (CKD) are more likely to have complications due to cardiovascular disease (CVD). This study was performed to investigate the prevalence of chronic kidney disease (CKD) and the relation of CKD and number of stenosed coronary vessels in patients who had undergone coronary angiography with suspected coronary artery disease (CAD).
The data of 1,010 consecutive patients who underwent coronary angiography for suspected CAD in Zhongda Hospital were analyzed. Estimated glomerular filtration rate (eGFR) was calculated with the abbreviated Modified Diet in Renal Disease (MDRD) Study equation. CKD was defined as presence of eGFR <60 ml/min per 1.73 m(2) and/or proteinuria. Luminal narrowing with at least 1 lesion =50% in the main branches of the coronary artery was considered as CAD. The number of stenotic arteries was recorded (1- to 3-vessel disease [VD]). A significant stenosis in the left main trunk was scored as 2-VD.
Patients with CAD had a significantly higher prevalence of CKD compared with patients without CAD (18.8% vs. 5.4%, p<0.001). CKD was significantly associated with CAD, 2-VD and 3-VD, versus without CAD (0-VD) (odds ratio [OR] = 2.163; 95% confidence interval [95% CI], 1.296-3.611; OR=2.478; 95% CI, 1.288-4.766; OR=2.504; 95% CI, 1.271-4.933; respectively) after adjustment for covariates.
There was a higher prevalence of CKD in patients with CAD diagnosed by coronary angiography, and it increased with the number of stenosed coronary vessels. CKD is a critical risk factor for CAD, especially 3-VD.
Journal of nephrology 07/2011; 25(2):219-24. · 1.65 Impact Factor
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ABSTRACT: BACKGROUND: Emerging evidence has indicated that the endothelial-to-mesenchymal transition (EndMT) is a crucial event during early stages of cardiac fibrosis. In the present study, we first investigated the influence of Irbesartan (Irb) on myocardial EndMT in diabetic rats. METHODS: Diabetic rats were divided into two groups: the diabetic group (DM) and the Irb-treated group (DM+Irb). Wistar-Kyoto rats served as controls. The pathological changes were investigated by microscopy. Immunofluorescence was performed to evaluate the co-expression of CD31 and fibroblast-specific protein 1 (FSP1). FSP1 and α-SMA expressions were detected by RT-PCR and Western blot analysis. EndMT was also studied in human aortic endothelial cells (HAECs) that had been exposed to high glucose (HG) levels. RESULTS: Increased interstitial fibrosis was detected in the DM group. Double labeling revealed CD31 expression in FSP1-positive cells in the DM group, and this expression was diminished by Irb treatment (P<0.05). In vitro, we found that HG stimulated angiotensin II synthesis in HAECs. When HAECs were exposed to HG, some of the cells acquired a spindle-shaped morphology and demonstrated a loss of CD31 labeling, which was attenuated by Irb treatment. FSP1 and α-SMA mRNA and protein expression levels were markedly upregulated in diabetic rats compared to controls, and their expressions were inhibited by Irb treatment (P<0.05). CONCLUSION: The results provide the novel insight that an angiotensin II receptor blocker might prevent diabetic cardiomyopathy by abrogating EndMT in diabetic rats.
International journal of cardiology 06/2011; · 7.08 Impact Factor
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ABSTRACT: Emerging evidence suggests that podocyte injury is a crucial event in the stage of diabetic nephropathy (DN), a process in which angiotensin II is implicated. In this study, the authors investigated the influence of irbesartan, an angiotensin receptor blocker, on the phenotypic alterations of podocytes in experimental DN.
DN was induced by combination of high-sucrose, high-fat diet and intraperitoneal injection of low dose of streptozotocin (35 mg/kg) in spontaneously hypertensive rats. Diabetic rats were treated with irbesartan (50 mg/kg/d) by gavage for 8 weeks. Nondiabetic normotensive Wistar-Kyoto rats, which have the same genetic background as spontaneously hypertensive rat, were used as controls. The renal histological changes were investigated by light and electron microscopy. The epithelial marker of nephrin and mesenchymal marker of desmin were detected by real-time reverse transcriptase-polymerase chain reaction and Western blotting.
Compared with controls, diabetic rats were associated with mesangial matrix deposition, thickening of glomerular basement membrane, albuminuria, loss of podocytes and effacement of foot processes. Furthermore, the expression of nephrin was significantly reduced whereas desmin was increased. Irbesartan treatment not only lowered blood pressure and albuminuria but also attenuated podocyte loss, maintenance of nephrin expression and inhibition of desmin expression.
This study demonstrates that early irbesartan intervention attenuates the podocyte damage and ameliorates phenotypic alterations of podocytes, which provides a novel insight for the early application of angiotensin receptor blocker to prevent the development of DN.
The American Journal of the Medical Sciences 03/2011; 341(3):207-14. · 1.39 Impact Factor
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ABSTRACT: Inflammatory cell infiltration plays a key role in the pathogenesis of tubulointerstitial damage in chronic renal diseases. In addition to secreting the profibrotic cytokines, monocytes themselves have been demonstrated to be directly associated with renal fibrogenesis. However, how infiltrating monocytes interact with resident cells and the underlying mechanisms remain elusive. In this study we investigated the effects of monocytes on phenotypic changes of human proximal tubular HK-2 cells. The typical epithelial cell morphology of HK-2 cells disappeared after co-culture with monocytes, accompanied by decreased E-cadherin expression, and increased α-SMA and fibronectin expression, suggesting that HK-2 cells undergo epithelial-mesenchymal transition (EMT). Further analysis revealed that the effects were dependent on direct contact of the two types of cells as conditioned medium had no effects. Interestingly, administration of CD18 antibody directly inhibited this process. Furthermore, by microarray and RT-PCR we found that NF-kB signaling may play a role in this process and blockade of this signaling pathway in HK-2 cells could inhibit ICAM-1 expression and EMT phenotypes. Taken together, these findings suggest that monocytes infiltration could directly induce EMT of HK-2 cells via upregulation ICAM-1 through NF-kB signaling pathway.
Journal of Cellular Biochemistry 02/2011; 112(6):1585-92. · 2.87 Impact Factor
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ABSTRACT: Podocyte injury and subsequent excretion in urine play a crucial role in the pathogenesis and progression of diabetic nephropathy (DN). Quantification of messenger RNA (mRNA) expression in urinary sediment by real-time PCR is emerging as a noninvasive method of screening DN-associated biomarkers. We hypothesized that the urinary mRNA profile of podocyte-associated molecules may provide important clinical insight into the different stages of diabetic nephropathy.
DN patients (N = 51) and healthy controls (N = 13) were enrolled in this study. DN patients were divided into a normoalbuminuria group (UAE<30 mg/g, n = 17), a microalbuminuria group (UAE 30∼300 mg/g, n = 15), and a macroalbuminuria group (UAE>300 mg/g, n = 19), according to their urinary albumin excretion (UAE). Relative mRNA abundance of synaptopodin, podocalyxin, CD2-AP, α-actin4, and podocin were quantified, and correlations between target mRNAs and clinical parameters were examined.
The urinary mRNA levels of all genes studied were significantly higher in the DN group compared with controls (p<0.05), and mRNA levels increased with DN progression. Urinary mRNA levels of all target genes positively correlated with both UAE and BUN. The expression of podocalyxin, CD2-AP, α-actin4, and podocin mRNA correlated with serum creatinine (r = 0.457, p = 0.001; r = 0.329, p = 0.01; r = 0.286, p = 0.021; r = 0.357, p = 0.006, respectively). Furthermore, podocalyxin mRNA was found to negatively correlate with eGFR (r = -0.349, p = 0.01).
The urinary mRNA profiles of synaptopodin, podocalyxin, CD2-AP, α-actin4, and podocin were found to increase with the progression of DN, which suggested that quantification of podocyte-associated molecules will be useful biomarkers of DN.
PLoS ONE 01/2011; 6(5):e20431. · 4.09 Impact Factor
