ABSTRACT
Objective To access the effects of aldosterone (ALD) and its receptor antagonist- spironolactone (SPI) on the production of reactive oxygen species (ROS) and apoptosis in podocytes and to explore the possible mechanism involved. Methods Conditionally immortalized mouse podocytes were divided into control group, ALD group, SPI group and SPI +ALD group. The level of ROS production and the expression of nephrin protein were assayed by fluorescent spectrophotometry and indirect immunofluorescence technology. The apoptosis rate of podocytes was monitored by flow cytometry. The expression of bax and bcl-2 mRNA and protein was detected by RT-PCR and Western blotting methods. The anti-oxidant N-acetylcysteine (NAC)was applied to determine whether the effects of ALD on podocytes were mediated by ROS pathway.Results Compared with the control group, ALD significantly increased ROS production in podocytes (P＜0.05). SPI completely abolished the above-mentioned effect of ALD (P＜0.05). ALD induced the down-regulation of the expression of nephrin and the up-regulation of podocytes apoptosis (P＜0.05), which was accompanied with the elevated expression of bax mRNA and protein and the reduced expression of bcl-2 mRNA and protein (P＜0.05). SPI or NAC prevented the above-mentioned changes induced by ALD (P＜0.05). Conclusion ALD increases theexpression of pro-apoptotic factor (bax) but decreases the expression of anti-apoptotic factor (bcl-2)to induce podocytes apoptosis through the mineralocorticoid receptor (MR) possibly via the mechanisms involving ROS pathway.
ABSTRACT
This study examined the effect of sulodexide on podocyte injury in rats with adriamycin nephropathy (AN). A total of 36 healthy male SD rats were randomly assigned to three groups: control group, AN group and sulodexide treatment group. Rat models of AN were established by a single tail intravenous injection of adriamycin (6.5 mg/kg) in both AN group and sulodexide treatment group. Sulodexide (10 mg/kg) was administered the rats in the treatment group once daily by garage from the first day of model establishment until the 14th day or the 28th day. Samples of 24-h urine and renal cortex tissues were harvested at day 14, 28 after the model establishment. Excretion of 24-h urinary protein was measured by Coomassie brilliant blue method. The pathological changes in renal tissues were observed by light microscopy and electron microscopy respectively. Heparanase mRNA was detected by RT-PCR. Expressions of desmin, CD2AP and heparanase were determined by immunohistological staining. The results showed that the expressions of heparanase mRNA and protein were increased in the glomeruli of AN rats at day 14 and 28 after the model establishment, which was accompanied by the increased expression of desmin and CD2AP. The mRNA and protein expression of heparanase was decreased in the sulodexide-treated rats as compared with AN rats at day 14 and 28. And, the protein expression of desmin and CD2AP was reduced as with heparanase in the sulodexide- treated rats. Proteinuria and podocyte foot process effacement were alleviated in the AN rats after sulodexide treatment. There was a positive correlation between the expression of heparanase and the expression of desmin and CD2AP (as well as 24-h urinary protein excretion). It was concluded that increased heparanase is involved in podocyte injury. Sulodexide can maintain and restore podocyte morphology by inhibiting the expression of heparanase in AN.
ABSTRACT
Purpose To observe the pathologic types of glomerular diseases which have high renal interstitial foam cells infiltration and to evaluate the relationship between infiltration of foam cells (FC) in renal interstitial tissue and pathologic parameters.Methods A total of 2 862 patients who had received renal biopsy were enrolled in this study. Patients with Alport syndrome (AS,n=5), membranous proliferative glomerular nephritis (MPGN,n=28), focal segmental glomerulosclerosis (FSGS,n=144), idiopathic membranous nephropathy (IMN,n=132), IgA nephropathy (IgAN,n=893) were divided into two groups:FC+ group with foam cells and FC- group without foam cells.Results Infiltration of foam cells in renal interstitial tissue was commonly seen in AS.The frequency of interstitial foam cells was 46.43% in MPGN, 20.14% in FSGS, 13.64% in IMN, and 6.27% in IgAN. It was found that the segmental glomerular sclerosis and interstitial fibrosis were more severe in FC+ group than that in FC- group.Conclusions The renal interstitial foam cells are most common in patients with AS, but also seen in patients with MPGN, FSGS, IMN and IgAN. There might be a relationship between glomerular sclerosis, interstitial fibrosis and infiltration of foam cells. The present of foam cells in the renal interstitial tissue may contribute to the progression of renal diseases.
ABSTRACT
The role of serum and glucocorticoid-induced kinase 1 (SGK1) pathway in the connective tissue growth factor (CTGF) expression was investigated in cultured human mesangial cells (HMCs) under high glucose. By using RT-PCR and Western blot, the effect of SGK1 on the CTGF expression in HMCs under high glucose was examined. Overexpression of active SGK1 in HMCs transfected with pIRES2-EGFP-S422D hSGK1 (SD) could increase the expression of phosphorylated SGK1 and CTGF as compared with HMCs groups transfected with pIRES2-EGFP (FP) under high glucose or normal glucose. Overexpression of inactive SGK1 in HMCs transfected with pIRES2-EGFP-K127N hSGK1 (KN) could decrease phosphorylated SGK1 and CTGF expression as compared with HMCs groups transfected with FP under high glucose. In conclusion, these results suggest that high glucose-induced CTGF expression is mediated through the active SGK1 in HMCs.
Subject(s)
Cells, Cultured , Connective Tissue Growth Factor/genetics , Connective Tissue Growth Factor/metabolism , Glucose/pharmacology , Immediate-Early Proteins/metabolism , Immediate-Early Proteins/physiology , Mesangial Cells/cytology , Mesangial Cells/metabolism , Protein Serine-Threonine Kinases/metabolism , Protein Serine-Threonine Kinases/physiology , Signal Transduction/drug effectsABSTRACT
Objective To study the effects of CD2-associated protein (CD2AP) on podocyte adhesion and extension ability and to explore its possible mechanism. Methods Conditionally immortalized murine podocyte cell line was cultured in RPMI 1640 medium at 33℃permissive conditions. The podocytes were transfected with CD2AP small interfering RNA (siRNA) and serambing sequences labeled with fluorescein were taken as control. The transfected podocytes were trypsinized and seed into collagen IV coated plates. The relative cell adhesion and cell area were examined 90 min later. Apoptotic rates of CD2AP siRNA transfected podoeytes and different PAN concentrations incubated podoeytes were detected by flow cytometer. The distribution of F-actin was observed under laser scanning confoeal microscope. Nephrin protein expression and its phosphorylation level were examined by immunofluorescence and Western blot. Results The relative ceil adhesion of CD2AP siRNA transfected podocytes was apparently lower than that of control group[(41.72±6.07)% vs (64.46±8.53)%, P<0.05]. The cell area analysis had the similar result. The apoptotic rate of CD2AP siRNA transfected podocytes was significantly higher than that of the controls [(5.73±0.61)% vs (3.26±0.45)%, P<0.05]. 100 mg/L PAN could markedly induce podocytes to apoptosis and impair cell adhesion ability (P<0.05). Nevertheless, no significant difference was found in cell body spreading (P>0.05). The distribution of F-actin in CD2AP depletion podocytes was apparently altered. The expression of nephrin protein and its phosphorylation level was conspicuously descended to some degree (P<0.05). Conclusions CD2AP depletion facilitates podocyte apoptosis and impairs cell adhesion function. Cytoskeleton confusion and nephrin signaling weakness caused by CD2AP depletion may he partly responsible for the decline of cell adhesion and spreading.
ABSTRACT
In order to investigate the effects of connective tissue growth factor (CTGF) antisense oligodeoxynucleotide (ODN) on plasminogen activator inhibitor-1 (PAI-1) expression in renal tubular cells induced by transforming growth factor β1 (TGF-β1) and to explore the role of CTGF in the degradation of renal extracellular matrix (ECM), a human proximal tubular epithelial cell line (HKC) was cultured in vitro. Cationic lipid-mediated CTGF antisense ODN was transfected into HKC. After HKC were stimulated with TGF-β1 (5 μg/L), the mRNA level of PAI-1 was detected by RT-PCR. Intracellular PAI-1 protein synthesis was assessed by flow cytometry. The secreted PAI-1 in the media was determined by Western blot. The results showed that TGF-β1 could induce tubular CTGF and PAI-1 mRNA expression. The PAI-1 mRNA expression induced by TGF-β1 was significantly inhibited by CTGF antisense ODN. CTGF antisense ODN also inhibited intracellular PAI-1 protein synthesis and lowered the levels of PAI-1 protein secreted into the media. It was concluded that CTGF might play a crucial role in the degradation of excessive ECM during tubulointerstitial fibrosis, and blocking the biological effect of CTGF may be a novel way in preventing renal fibrosis.
ABSTRACT
In order to investigate the effects of connective tissue growth factor (CTGF) antisense oligodeoxynucleotide (ODN) on plasminogen activator inhibitor-1 (PAI-1) expression in renal tubular cells induced by transforming growth factor beta1 (TGF-beta1) and to explore the role of CTGF in the degradation of renal extracellular matrix (ECM), a human proximal tubular epithelial cell line (HKC) was cultured in vitro. Cationic lipid-mediated CTGF antisense ODN was transfected into HKC. After HKC were stimulated with TGF-beta1 (5 microg/L), the mRNA level of PAI-1 was detected by RT-PCR. Intracellular PAI-1 protein synthesis was assessed by flow cytometry. The secreted PAI-1 in the media was determined by Western blot. The results showed that TGF-beta1 could induce tubular CTGF and PAI-1 mRNA expression. The PAI-1 mRNA expression induced by TGF-beta1 was significantly inhibited by CTGF antisense ODN. CTGF antisense ODN also inhibited intracellular PAI-1 protein synthesis and lowered the levels of PAI-1 protein secreted into the media. It was concluded that CTGF might play a crucial role in the degradation of excessive ECM during tubulointerstitial fibrosis, and blocking the biological effect of CTGF may be a novel way in preventing renal fibrosis.
ABSTRACT
To investigate the role and mechanisms of apoptosis and apoptosis signaling pathway in 5/6 nephrectomy rat model (SNx), the mRNA and protein levels of caspase-3, -8, -9 and apoptosis were detected by in situ end labeling ( TUNEL ), immunohistochemistry, RT-PCR, Western-blotting 1,2, 4, 8, 12, 16, 26 and 40 weeks after 5/6 nephrectomy rat model was made respectively. The rats in the model group developed glomerular sclerosis and renal interstitial fibrosis. The number of the apoptototic cells in glomeruli, renal tubule and renal interstitium was remarkably higher in the model group than that in the control group (P＜0.05, P＜0.01). Changes of mRNA and protein level of caspase-3, -8, -9 had the same tendency and was up-regulated wavily in the rat model compared with the control group (P＜0.05). Peaks in model appeared on the 4th and the 40th week respectively. The growth amplitude of caspase-9 was remarkably higher than that of caspase-8. It is concluded that the development of 5/6 nephrectomy rat model was correlated with the apoptosis of glomeruli, renal tubule and renal interstitium. Both of death receptor and mitochondria signaling pathways are involved in the process and the latter might play a primary role.
ABSTRACT
In current study, the expressions of protein kinase C (PKC)-α, βⅠ and βⅡ as well as their correlation to the expression of transforming growth factor-βⅠ (TGF-βⅠ) and vascular endothelial growth factor (VEGF) were investigated in glomeruli of normal renal tissues taken from human kidney tumors and kidney tissues from patients with diabetic nephropathy (DN). The accumulation of glomerular extracelluar matrix (ECM) was determined by PAS staining, the expressions of PKC-α,PKC-βⅠ, PKC-βⅡ, TGF-βⅠ and VEGF were measured by semi-quantitative immunohistochemistry.Our results showed that in glomeruli of normal renal tissues, PKC-α and βⅡ had a strong expression whereas the expression of PKC-βⅠ was weak; in glomeruli of DN patients, the expressions of PKC-α,PKC-βⅠ, VEGF and TGF-βⅠ and the accumulation of ECM increased significantly, but the expression of PKC-βⅡ decreased markedly. Meanwhile, the expressions of PKC-α and βⅠ had a positive correlation to the expressions of VEGF and TGF-βⅠ respectively, whereas PKC-βⅡ showed no correlation to VEGF and TGF-βⅠ. It is concluded that the expressions of PKC-α, βⅠ and βⅡ in glomeruli of normal subjects and DN patients are different. PKC-α seems to play a critical role in human DN by up-regulating VEGF expression, whereas PKC-βⅠ is relatively important for the up-regulation of TGF-βⅠ and the accumulation of ECM under diabetic conditions.
ABSTRACT
In current study, the expressions of protein kinase C (PKC)-alpha, betaI and betaII as well as their correlation to the expression of transforming growth factor-betaI (TGF-betaI) and vascular endothelial growth factor (VEGF) were investigated in glomeruli of normal renal tissues taken from human kidney tumors and kidney tissues from patients with diabetic nephropathy (DN). The accumulation of glomerular extracelluar matrix (ECM) was determined by PAS staining, the expressions of PKC-a, PKC-betaI, PKC-betaII, TGF-betaI and VEGF were measured by semi-quantitative immunohistochemistry. Our results showed that in glomeruli of normal renal tissues, PKC-alpha and betaII had a strong expression whereas the expression of PKC-betaI was weak; in glomeruli of DN patients, the expressions of PKC-alpha, PKC-betaI, VEGF and TGF-betaI and the accumulation of ECM increased significantly, but the expression of PKC-betaII decreased markedly. Meanwhile, the expressions of PKC-alpha and betaI had a positive correlation to the expressions of VEGF and TGF-betaI respectively, whereas PKC-betaII showed no correlation to VEGF and TGF-betaI. It is concluded that the expressions of PKC-alpha, betaI and betaII in glomeruli of normal subjects and DN patients are different. PKC-alpha seems to play a critical role in human DN by up-regulating VEGF expression, whereas PKC-betaI is relatively important for the up-regulation of TGF-betaI and the accumulation of ECM under diabetic conditions.
ABSTRACT
To investigate the role and mechanisms of apoptosis and apoptosis signaling pathway in 5/6 nephrectomy rat model (SN(x)), the mRNA and protein levels of caspase-3, -8, -9 and apoptosis were detected by in situ end labeling (TUNEL), immunohistochemistry, RT-PCR, Western-blotting 1, 2, 4, 8, 12, 16, 26 and 40 weeks after 5/6 nephrectomy rat model was made respectively. The rats in the model group developed glomerular sclerosis and renal interstitial fibrosis. The number of the apoptototic cells in glomeruli, renal tubule and renal interstitium was remarkably higher in the model group than that in the control group (P < 0.05, P < 0.01). Changes of mRNA and protein level of caspase-3, -8, -9 had the same tendency and was up-regulated wavily in the rat model compared with the control group (P < 0.05). Peaks in model appeared on the 4th and the 40th week respectively. The growth amplitude of caspase-9 was remarkably higher than that of caspase-8. It is concluded that the development of 5/6 nephrectomy rat model was correlated with the apoptosis of glomeruli, renal tubule and renal interstitium. Both of death receptor and mitochondria signaling pathways are involved in the process and the latter might play a primary role.
ABSTRACT
A potential pathological role of angiopoietins (Ang) in glomeruli following podocyte injury-induced progressive glomerulosclerosis was explored. Eighty male Wistar rats were randomly allocated into sham operation group (Sham, n = 25), Uninephrectomy group (UPHT, n = 25) and Uninephrectomy+Daunorubicin group (DRB, n = 30). In DRB group, daunorubicin (5 mg/kg) was injected via tail vein on the 7th and 14th day after uninephrectomy. At week 1, 2, 4, 6 and 8 respectively following establishment of the animal model, 5 rats in Sham group and UPHT group, and 6 in DRB group were taken respectively for determining 24-h urinary protein excretion rate (24hUPER), blood urea nitrogen (BUN) and serum creatinine (Scr). The sections of kidneys were examined by an electric microscope, PAS staining, immunohistochemical staining and in situ hybridization histochemistry. The results showed that 24hUPER, BUN and Scr in DRB group were more than those in Sham group and UPHT group at the same time points, and there was a trend towards an increase on level of GSI in DRB group from week 2 to week 8. Electric microscopy revealed that podocyte injury presented in DRB group. The expression of Ang1 mRNA and protein in glomeruli of DRB group was decreased, while the expression of Ang2 protein in glomeruli of DRB group increased. Meanwhile, the expression of Ang1 mRNA had a negative correlation with the expression of Ang2 mRNA, and the expression of Ang1 protein had a positive correlation with the expression of Ang1 mRNA, and had a negative correlation with 24hUPER, BUN, Scr, glomerular sclerotic index (GSI), the expression of Ang2 protein and CoIV protein. The expression of Ang2 protein had a positive correlation with the expression of Ang2 mRNA, and had a positive correlation with 24hUPER, BUN, Scr, GSI, the expression of CoIV protein. It was concluded that podocyte injury might lead to an alteration in the expression of Ang1 and Ang2 within glomeruli. Ang2 may get rid of inhibition from Ang1 for downregulation of the Ang1 expression, which facilitate upregulation of the Ang2 expression in glomeruli to promote progressive glomerulosclerosis in the rats.
ABSTRACT
A potential pathological role of angiopoietins (Ang) in glomeruli following podocyte injury-induced progressive glomerulosclerosis was explored. Eighty male Wistar rats were randomly allocated into sham operation group (Sham, n = 25), Uninephrectomy group (UPHT, n = 25) and Uninephrectomy+Daunorubicin group (DRB, n= 30). In DRB group, daunorubicin (5 mg/kg)was injected via tail vein on the 7th and 14th day after uninephrectomy. At week 1, 2, 4, 6 and 8 respectively following establishment of the animal model, 5 rats in Sham group and UPHT group,and 6 in DRB group were taken respectively for determining 24-h urinary protein excretion rate (24hUPER), blood urea nitrogen (BUN) and serum creatinine (Scr). The sections of kidneys were examined by an electric microscope, PAS staining, immunohistochemical staining and in situ hybridization histochemistry. The results showed that 24hUPER, BUN and Scr in DRB group were more than those in Sham group and UPHT group at the same time points, and there was a trend towards an increase on level of GSI in DRB group from week 2 to week 8. Electric microscopy revealed that podocyte injury presented in DRB group. The expression of Ang1 mRNA and protein in glomeruli of DRB group was decreased, while the expression of Ang2 protein in glomeruli of DRB group increased. Meanwhile, the expression of Angl mRNA had a negative correlation with the expression of Ang2 mRNA, and the expression of Angl protein had a positive correlation with the expression of Angl mRNA, and had a negative correlation with 24hUPER, BUN, Scr, glomerular sclerotic index (GSI), the expression of Ang2 protein and CoIV protein. The expression of Ang2 protein had a positive correlation with the expression of Ang2 mRNA, and had a positive correlation with 24hUPER, BUN, Scr, GSI, the expression of CoIV protein. It was concluded that podocyte injury might lead to an alteration in the expression of Angl and Ang2 within glomeruli. Ang2 may get rid of inhibition from Ang1 for downregulation of the Angl expression, which facilitate upregulation of the Ang2 expression in glomeruli to promote progressive glomerulosclerosis in the rats.
ABSTRACT
The antinephritic effect of lipo-prostaglandin E1, prostaglandin E1 incorporated in lipid microspheres was investigated using an experimental model of mesangial proliferative glomerulonephritis (MsPGN). Twenty-two female rats were randomly divided into nephritic group (N, n= 6),lipo-prostaglandin E1 treated group (NL, n = 8) and control group (C, n = 6). Lipo-prostaglandin E1 was given intravenously at 40 μg · kg-1 · d-1 from the 6th week to the 8th week. Twenty-four h urinary protein contents and blood creatinine (Cr) were determined and the pathological changes were observed in the experiment. The expression of proliferating cell nuclear antigen (PCNA), extracellular matrix (fibronectin, FN; collagen type Ⅳ, Col Ⅳ) and transforming growth factor β1(TGFβ1) was detected by using immunohistochemistry. The results showed that lipo-prostaglandin E1 significantly inhibited the glomerular histopathological changes as well as the elevation of plasma Cr (P＜0.05). The overexpression of PCNA, FN, Col Ⅳ and TGFβ1 were also obviously inhibited in group NL as compared with the group N (P＜0.01). It was suggested that lipo-prostaglandin E1could improve renal function, inhibit the proliferation of glomerular cells and reduce the deposition of extracellular matrix, which may be related to the down-regulation of the TGFβ1 expression.
ABSTRACT
In order to explore the role of connective tissue growth factor (CTGF) in the pathogenesis of renal tubulointerstitial fibrosis, 48 Wistar rats were randomly divided into sham-operated and unilateral ureteral obstruction (UUO) group. On the postoperative day 1, 3, 7 and 14, the rats were killed and the kidneys were removed. The renal tubulointerstitial injury index was evaluated according to the MASSON staining. The mRNA levels of CTGF, transforming growth factor-β1(TGF-β1), collagen Ⅰ (col Ⅰ ), and plasminogen activator inhibitor-1 (PAI-1) were detected using reverse transcriptional-polymerase chain reaction (RT-PCR). Immunohistochemistry was performed to evaluate the protein expression of the above factors, and the relations among them were analyzed. Quantitative expression of CTGF protein in the kidneys was also assessed using Western blot. The results showed that TGF-β1 mRNA level was increased at first day after UUO, followed by a marked elevation of CTGF mRNA level, which began to increase 3 days after UUO (P＜0.01). With the progression of the disease, the mRNA expression of CTGF, col Ⅰ and PAI-1 was increased progressively. Immunohistochemistry revealed that the CTGF protein expression was significantly increased in fibrotic areas and tubular epithelial cells 3 days after UUO. On the post-UUO day 7, the protein level of CTGF was positively related to the renal tubulointerstitial injury index (r =0.62, P＜0.01), the expression of TGF-β1 (r=0.85, P＜0.01), col Ⅰ (r=0.78, P＜0.01),and PAI-1(r=0.76, P＜0.01). Upon Western blot analysis, CTGF protein expression began to increase 3 days after UUO, and appeared progressively throughout the time course (P＜0. 01, as compared with sham-operated group). It is concluded that CTGF can be induced by TGF-β and mediate various profibrotic actions of this cytokine, such as increasing extracellular matrix (ECM)synthesis and decreasing ECM degradation. The increased expression of CTGF may play a crucial role in the development and progression of tubulointerstitial fibrosis.
ABSTRACT
The different sera proteomic components between uremia patients and normal subjects were studied through two-dimensional gel electrophoresis technique. Immobilized pH gradient twodimensional polyacrylamide gel electrophoresis (2DE), silver staining, ImageMaster 2D 5.0 analysis software, matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDITOF-TOF-MS) and IPI human database searching were used to separate and identify the proteome of the sera from the patients with uremia. The results showed that satisfactory 2DE patterns of the serum proteins were obtained. Twenty-six protein spots showed significant difference in quantity in uremia patients, and 20 protein spots were identified by MALDI-TOF-TOF-MS. It was concluded that good reproducibility could be obtained by applying immobilized pH gradient 2DE to separate and identify the proteome in serum, which provided the foundation for the further study on uremia toxins pertaining to protein.
ABSTRACT
To investigate the expression and the role of three isoforms of Serum and Glucocorticoid-inducible Kinase (SGK) in experimental diabetic nephropathy (DN), 12 male C57BL/6 mice of 8-weeks-old were divided into two groups. Streptozotocin (STZ)-induced diabetic nephropathy and normal controls were analyzed at the end of the 4th week after the induction of diabetes. Renal hemodynamics and histological studies were performed. The expression of SGK1 mRNA, SGK2 mRNA and SGK3 mRNA of kidney cortex were measured by RT-PCR, and the cortical SGK1 protein was detected with Western blotting. Our results showed that the blood glucose, blood HbA1c, 24h urinary protein, creatinine clearance and the renal index were all increased in DN group. More extracellular matrix (ECM) accumulation was observed. The level of cortical SGK1 mRNA and protein were up-regulated in DN group in comparison with control group. SGK2 and SGK3 mRNA were elevated in DN mice. In DN, mRNA level of three SGK isoforms and SGK1 protein were increased significantly. It is concluded that SGKs may contribute to the early renal injury of DN.
ABSTRACT
The different sera proteomic components between uremia patients and normal subjects were studied through two-dimensional gel electrophoresis technique. Immobilized pH gradient two-dimensional polyacrylamide gel electrophoresis (2DE), silver staining, ImageMaster 2D 5.0 analysis software, matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-TOF-MS) and IPI human database searching were used to separate and identify the proteome of the sera from the patients with uremia. The results showed that satisfactory 2DE patterns of the serum proteins were obtained. Twenty-six protein spots showed significant difference in quantity in uremia patients, and 20 protein spots were identified by MALDI-TOF-TOF-MS. It was concluded that good reproducibility could be obtained by applying immobilized pH gradient 2DE to separate and identify the proteome in serum, which provided the foundation for the further study on uremia toxins pertaining to protein.
Subject(s)
Blood Protein Electrophoresis , Blood Proteins/analysis , Case-Control Studies , Electrophoresis, Gel, Two-Dimensional/methods , Proteome/analysis , Proteome/chemistry , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Uremia/bloodABSTRACT
To investigate the expression and the role of three isoforms of Serum and Glucocorticoidinducible Kinase (SGK) in experimental diabetic nephropathy (DN), 12 male C57BL/6 mice of 8-weeks-old were divided into two groups. Streptozotocin (STZ)-induced diabetic nephropathy and normal controls were analyzed at the end of the 4th week after the induction of diabetes. Renal hemodynamics and histological studies were performed. The expression of SGK1 mRNA, SGK2 mRNA and SGK3 mRNA of kidney cortex were measured by RT-PCR, and the cortical SGK1 protein was detected with Western blotting. Our results showed that the blood glucose, blood HbA1c, 24-h urinary protein, creatinine clearance and the renal index were all increased in DN group. More extracellular matrix (ECM) accumulation was observed. The level of cortical SGK1 mRNA and protein were up-regulated in DN group in comparison with control group. SGK2 and SGK3 mRNA were elevated in DN mice. In DN, mRNA level of three SGK isoforms and SGK1 protein were increased significantly. It is concluded that SGKs may contribute to the early renal injury of DN.
ABSTRACT
To investigate the role of connective tissue growth factor (CTGF) in transdifferentiation of human renal tubular epithelial cell (HKC), in vitro cultured HKC cells were divided into 3 groups: negtive control, low dose CTGF-treated group (rh CTGF, 2.5 ng/ml) and high dose CTGF-treated (rhCTGF, 5.0 ng/ml). Then the expression of alpha-smooth muscle actin (alpha-SMA) were assessed by indirect immuno-fluorescence, and the percentage of alpha-SMA positive cells were assessed by flow cytometry. RT-PCR were also performed to examine the mRNA level of alpha-SMA. Upon the stimulation of different concentrations of rhCTGF, the expression of alpha-SMA were markedly stronger than that in negative controls. The percentages of alpha-SMA positive cells were significantly higher in the stimulated groups than that of negative controls (38.9%, 65.5% vs 2.4%, P<0.01). alpha-SMA mRNA levels were also up-regulated by the stimulation of rhCTGF (P<0.01). These results suggest that CTGF can promote the transdifferentiation of human renal tubular epithelial cells towards myofibroblast (Myo-F).