Correlation between the ratio of intima/media thickness and inflammatory factors in renal small artery of diabetic nephropathy rats / 中华肾脏病杂志

Objective To observe the change of intima/media thickness ratio and expression of inflammatory factors in renal small artery of diabetic rats, and to explore the correlations of intim/media ratio with inflammatory factors and vascular lesions of diabetic nephropathy (DN) rats. Methods Seventy healthy SD rats were randomly divided into diabetic nephropathy group (DN, n=40) and normal control group (N, n=30). DN rat model was induced by intraperitoneal injection of streptozotocin (STZ). Thirty-five DN rats were successfully established. N group received same dose of citrate buffer. Rats were sacrificed after 4, 12, 24 weeks respectively.The intima/media thickness ratio in renal small artery was detected by immunofluorescence. The monocyte chemoattractant protein-1 (MCP-1) protein and mRNA expression of renal small artery were detected by immunohistochemistry and in-situ hybridization at each time point. Results Blood glucose and urine protein excretion (24 h) at different time points in DN group were significantly higher than those of N group (P＜0.05). From the 12th week, Scr, BUN, serum phosphorus were significantly higher than those of N group (P＜0.05). At the 4th week, renal small artery had the expression of MCP-1 protein and mRNA. The expression increased gradually with time, reached the highest at the 24th week, and was significantly higher than that of N group at each time point (P＜0.05). Immunofluorescence results showed that as compared to N group, in the first 4 weeks, intima/media thickness ratio in DN group was not different, at the 12th week the ratio was higher but without significant difference, at the 24th week the ratio was significantly higher (P＜0.05). Small artery intima/media thickness ratio of DN group was positively correlated with MCP-1, cholesterol, triglyceride, serum phosphate (r=0.742, P＜0.01; r=0.740, P＜0.01; r=0.829, P＜0.01; r=0.580, P＜0.01). Conclusions The arterioles intima/media thickness ratio of early DN is significantly correlated with MCP-1, lipids and phosphorus. MCP-1 may be involved in the DN vascular disease.

Effects of high glucose and insulin on expression of glucose transporter 4, Cbl-associated protein and cytoskeleton protein F-actin in rat glomerular mesangial cells in vitro / 中华肾脏病杂志

Objective To investigate the effects of high glucose and insulin on the expression of glucose transporter 4 (GLUT4), Cbl-associated protein (CAP) and cytoskeleton protein F-actin of glomerular mesangial cells (GMCs), in order to explore the function of GLUT4, Cbl-associated protein and F-actin in the pathogenesis and development of diabetic nephropathy (DN). Methods Cultured 1097 rat glomerular mesangial cells were divided into 8 groups: control, 10-9 mol/L insulin, 10-8 mol/L insulin, 10-6 mol/L insulin, high glucose (30 mmol/L), mannitol (25 mmol/L mannitol+5 mmol/L glucose), high glucose plus 10-6 mol/L insulin, high glucose plus 10-9 mol/L insulin. Expression of CAP mRNA and GLUT4 was measured by RT-PCR and immunohistochemistry method. F-actin was stained by rhodamine-pholloidin and the fluorescent intensity was calculated by image analysis system. Results The expression of GLUT4 mRNA and protein, CAP mRNA was found in normal giomerular mesangial cells (control), and there was no significant difference in 10-9 mol/L insulin group. The expression of GLUT4 mRNA (P<0.05) and protein (P<0.01), CAP mRNA (P<0.01) level was decreased in high glucose group compared with that of control group, but there was no significant difference in mannitol group. The expression of GLUT4 and CAP mRNA up-regulated with the increase of concentration of insulin. The expressions of GLUT4 mRNA in 10-8 mol/L insulin and 10-6 mol/L insulin groups were 2.06-fold and 2.66-fold of 10-9 mol/L insulin group, of GLUT4 protein were 1.93-fold and 2.83-fold of control, and of CAP mRNA were 1.91-fold and 2.15-fold of control, respectively. The expressions of GLUT4 mRNA, GLUT4 protein, CAP mRNA in high glucose plus insulin group were 2.15-fold, 2.08-fold, 2.14-fold of high glucose group respectively. High glucose decreased the fluorescent intensity of F-actin to 44.5% (P<0.01). 10-8 mol/L insulin and 10-6 mol/L insulin groups increased to 1.224-fold (P<0.05), 1.296-fold (P<0.01) in a concentration-dependent manner. The spearman correlation coefficient between GLUT4 and F-actin was 0.929 (P=0.001), between GLUT4 mRNA and CAP mRNA was 0.905 (P=0.002). Conclusions (1) A certain expression of GLUT4 mRNA and protein, CAP mRNA from GMC is found in normal glomerular mesangial cells. (2) High glucose can inhibit the expression of GLUT4 and CAP mRNA significantly, and facilitate the depolymerization of F-aetin. (3) Insulin can reverse down-regnlation of GLUT4 and CAP mRNA caused by high glucose. (4) GLUT4, CAP and F-actin are important factors in the development of DN.

Influence of different reference GFR distribution on racial coefficient in GFR estimating equation / 中华肾脏病杂志

Objective To illustrate if the racial coefficient (Rc) be biased by different reference GFR (rGFR) distribution among studies. Methods 1405 white and 321 African American participants in MDRD study and 684 chronic kidney disease(CKD)patients in Chinese eGFR Investigation Study were included.Firstly.the unweighted datasets of white and Chinese were stacked together.rGFR,age and plasma creatinine (Pcr) were log transformed.Linear regression model was constructed using log transformed rGFR as dependent,gender,race and log transformed Pcr and age as independent.Unweighted RC (uRC) for Chinese was calculated.Then.the Chinese CKD distribution of rGFR was weighted to be the same as that in White American.and weighted RC (wRC)for Chinese was calculated.The cases of White.and African-American were stacked together.The cases of African-American were weighted to make the rGFR distribution the same as that in White-American and Chinese population respectively,and RCs for African-American were calculated. Resuits The uRC for Chinese was 1.197(1.180-1.211)and the wRC was 1.130 (1.117-1.143).The two RCs did not overlap with each other.The RCs for African-American were 1.205(1.19-1.219)and 1.233(1.219-1.247)respectively. Conclusions The RCs were influenced by the difference of rGFR distribution.To find out the real RC.an intemational collaborative study iS needed,with the same rGFR measure method.strict control of Pcr measurement,and the same rGFR distribution.

Multi-disciplinary collaboration in management of acute kidney injury caused by crush syndrome after earthquake / 中华内科杂志

On May 12,2008,a disastrous earthquake scaled 8.0 Richter hit Wenchuan,Sichuan province in China.Treating the acute kidney injury caused by crush syndrome in survivals of the earthquake has been a big challenge to the nephrologists.In this paper,we shared our experiences on the multi-disciplinary collaboration in management of acute kidney injury caused by crush syndrome.In addition to surgical therapy for crush injury and compartment syndrome and the renal replacement therapy for acute renal injury and its related complications,the early multi-disciplinary collaboration including rehabilitation,mental health care,infection control and ICU also contributed greatly to the successful treatment of the victims of the earthquake.

Interventional effect of irbesartan on vascular endothelial growth factor and its FIk-1 receptor expressions in the kidney of diabetic rats / 中国组织工程研究

BACKGROUND: Some studies have presented that vascular endothelial growth factor and its receptor system may take part in onset and development of diabetic nephropathy (DN).OBJECTIVE: To further verify the interventional effects of irbesartan on vascular endothelial growth factor (VEGF) and its Flk-1 receptor expressions in kidney of diabetes mellitus (DM) rat, and the possible mechanism of irbesartan.DESIGN: Randomized control animal study.SETTING: West China Hospital of Sichuan University.MATERIALS: Eighteen male closed colony SD rats weighing 150-200 g were cared in standardization.METHODS: This study was performed at Laboratory of West China Hospital of Sichuan University from August 2006 to April 2007. All rats were randomly divided into a DN group, an irbesartan group and a normal control group, with 6 rats in each group. 10 g/L streptozotocin (55 mg/kg) was intraperitoneally injected to establish models; rats in the control group were administrated with the same dosage of citric acid buffer solution; rats in the irbesartan group were administrated with 3 mg/(kg·d) irbesartan after model establishment. VEGF and FIk-1 expressions were detected using reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemistry technique; while, urine protein level, area and volume of renal glomerulus were detected, and correlations of data were analyzed.MAIN OUTCOME MEASURES: ①Renal pathological indicators, urine protein level, area and volume of renal glomerulus; ②VEGF and Flk-1 expressions;③renal immunohistochemical examination;④ correlation analysis.RESULTS:① Renal pathological examination by HE staining indicated that renal glomerulus was remarkably enlarged in the DN group; mesangial matrix was increased; mesangial cells were also increased; renal tubule was expanded. The lesions in the irbesartan group were milder compared to the DN group. Urine protein level in the DN group was significantly higher compared to the control group (P ＜ 0.01); renal weight/body mass, area and volume of renal glomerulus were significantly higher compared to the control group (P ＜ 0.01); urine protein level, renal weight/body mass, area and volume of renal glomerulus in the irbesartan group were significantly lower compared to the DN group (P ＜ 0.01). ② By the 16th week,VEGF and Flk-1 expressions in the DN group were significantly up-regulated compared to control group (P ＜ 0.05); while,VEGF and Flk-1 expressions in the irbesartan group were also up-regulated compared to the control group by the 16th week (P ＜ 0.05) but down-regulated compared to the DN group (P ＜ 0.05). ③ VEGF staining in the DN group was darker compared to control group (P ＜ 0.01), while the staining in the irbesartan group was also darker compared to the control group (P ＜0.01), but the staining in the irbesartan group was lighter compared to the DN group (P ＜ 0.01). Flk-1 staining was similar to the VEGF. ④ VEGF and Flk-1 were positively correlated, with urine protein level, area and volume of renal glomerulus (P ＜0.05).CONCLUSION: VEGF and its Flk-1 receptor play important roles in DN pathogenesis. Over expressions may cause renal injury, but irbesartan (angiotensin Ⅱ receptor antagonist) has the protective effects on kidney through inhibiting abnormal expression of VEGF and Flk-1.

Effects of shear stress on expression of plasminogen activator (tPA and uPA) in cultured kidney proximal tubular epithelial cells and its significance / 生物医学工程学杂志

In this study, we assessed the effects of shear stress on the expression of plasminogen activator(tPA and uPA) mRNA in cultured NRK-52E cells (a kidney proximal tubular epithelial cell line of normal rat origin) and investigated the mechanism of tubulointerstitial extracellular matrix (ECM) remodeling in the early stage of diabetic nephropathy (DN). The cultured NRK-52E cells were exposed to shear stress of 5 and 10 dyn/cm2 for 1, 3 and 6 hours respectively. Semi-quantity RT-PCR was used to detect the expression of tPA and uPA mRNA. Shear stress down-regulated the expression of tPA and uPA mRNA in cultured NRK-52E cells in a magnitude and time-dependent way. The results suggested that the increased tubular shear stress in the early-stage of DN could decrease the expression of tPA and uPA in renal proximal tubular cells, lead to the reduction of tubulointerstitial fibrinolytic activity and involve in the remodeling of ECM.

Correlation between the ratio of intima to tunica media thickness and the expression of bone matrix proteins in small renal artery of diabetic nephropathy rats / 中华肾脏病杂志

Objective To observe the expression of bone matrix proteins and the change of intima-tunica media thickness ratio in diabetic rat small renal artery and to explore their correlation and effects on diabetic nephropathy. Methods Seventy healthy SD rats were randomly divided into diabetic group(DN,n=40)and normal control group(N,n=30).DN rat model was induced by streptozotocin(STZ)intraperitoneal injection and the N group rats were given the same dose of citrate buffer.Thirty-five rats were successfully induced in DN group.The rats were sacrificed at week 4,12 and 24,respectively.The protein and mRNA expression of core-bind factor alpha 1(Cbfcd).bone morphogenetic protein 2(BMP-2)and matrix Gla protein(MGP)in smallrenal artery were detected by immunohistochemistry,in-situ hybridization and real-time PCR at each time point. Results Cbfctl and BMP-2 were expressed obviously in small renal artery of DN group by immunohistochemistry stain and in-situ hybridization from 4 to 24 weeks compared with N group at each time point,reaching the peak at week 24.Real-time PCR showed that the MGP mRNA was evidently increased at week 4,slightly decreased at week 12,lowest at week 24in DN group.The BMP-2 mRNA began to increase from week 4 onward,being peak at week 24in DN group.The ratio of intima to tunica media thickness had no significant difference in DN group compared with N group at week 4,but at week 12 and 24 there were significant difference between them.There was a positive correlation between Cbfα1 and BMP-2 expression,but they were negatively correlated with the expression of MGP.The ratio of intima to tunica media thickness was significantly-correlated with the expression of Cbfα1 and BMP-2. Conclusions The ratio of intima to tunica media thickness is positively correlated with Cbfα1 and BMP-2 in small renal artery of early DN.Cbfα1,BMP-2 and MGP may be involved in the progression of vascular lesions in DN.

The experimental study on the relationship between proangiogenic factors and the peritubular angiogenesis of diabetic renal / 中国实用内科杂志

Objective To explore the role and significance of vascular endothelial growth factor(VEGF)and angiopoietin-2(Ang-2)in peritubular angiogenesis of diabetic kidney.Methods diabetic rats were induced by Streptozotocin.The expressions of VEGF and Ang-2 in renal tissue of rats were detected by immunohisochemistry.VEGF and Ang-2 mRNA in kidney was also detected by RT-PCR,and quantified by computerimage analysis.Results From 2-week to 24-week,VEGF mRNA level in diabetic renal upregulated continuously compared with control group,with peak level at 16 and 20 weeks.VEGF immunostaining in diabetic renal tubuli increased apparently compared with control group.Ang-2 mRNA in diabetic renal was only detected at 16 and 20 weeks.Ang-2-expressing peritubular microvessel in diabetic renal cortex was found by immunohistochemistry from 12 -week to 24-week with peak level at 16 week.No detecable Ang-2 mRNA and immunostaining were found in control renal.The changes correlated VEGF with Ang-2 in diabetic renal after 12 weeks.Conclusion There are the formation of Ang-2-staining peritubular microvessels in diabetic renal cortex in middle and later stages.VEGF and Ang-2 take part in angiogenesis in diabetic renal.

Effect of high glucose, angiotensin II and receptor antagonist Losartan on the expression of connective tissue growth factor in cultured mesangial cells / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>To observe the effect of high glucose, angiotensin II (AngII) and Losartan on the expression of connective tissue growth factor (CTGF) mRNA in cultured mesangial cells (MCs).</p><p><b>METHODS</b>MCs of SD rats were isolated and cultured. High glucose (30 mmol/L) and AngII (10(-9), 10(-7), and 10(-5) mol/L) were added to the medium for 72 hours to observe the influence on CTGF mRNA expression. Losartan of 10(-5) mol/L and AngII of 10(-5) mol/L were added to the medium to observe the effects of Losartan on CTGF mRNA expression stimulated by AngII. The expressions of CTGF mRNA were detected by reverse transcriptase polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>RT-PCR showed that high glucose and AngII up-regulated the expression of CTGF mRNA, and AngII stimulated the expression in a dose-dependent manner. Expression of CTGF mRNA induced by AngIIwas partially suppressed by 10(-5) mol/L Losartan (P < 0.05).</p><p><b>CONCLUSIONS</b>High glucose and AngII can enhance the expression of CTGF mRNA and thus be involved in the process of renal fibrosis. Losartan can have a partial fibrogenesis-inhibiting effect, with implications for the treatment of renal fibrosis.</p>

Effects of turicamycin on proliferation of high glucose-induced glomerular mesangial cells and its mechanism study / 中华肾脏病杂志

Objective To observe the effects of turicamycin-inhibitor of N-glycosylation of proteins on expression of (?1 integrin,FAK and cyclin D1 in high glucose-induced glomerular mesangial cells (CMC), and to explore the mechanism concerned. Methods Cultured HBZY-1 rat mesangial cells were divided into 5 groups:control group;high glucose group;mannitol group;high glucose plus TM group; TM group.The expression of ?1 integrin was measured by flow cytometry, expression of FAK and cyclin D1 was measured by immunohistochemistry,and proliferation of GMCs was measured by MTT. Results There was a little expression of ?1 integrin, FAK and cyclin D1 on normal mesangial cells. High glucose induced the proliferation and increased the expression of ?1 integrin and cyclin D1.There was no significant difference in mannitol group as compared to control group.The expression of (?1 integrin FAK and cyclin D1 decreased notably by TM.TM could also decrease proliferative abilitiy of cells. All the effects of TM were dose-dependent. Conclusion Through blocking glycosylation of glycoprotein, TM can suppress cellular proliferation and expression of pi integrin induced by high glucose in a dose-dependent manners,then pi integrin affects the expression of FAK and cyclin D1.

Expression of glucose transporter 4 and cyclin kinase inhibitor p21 in cultured glomerular mesangial cells stimulated by high glucose / 中华肾脏病杂志

Objective To elucidate the relationship between expressive level alteration of glucose transporter 4(GLUT 4) mRNA,cyclin kinase inhibitor p21 mRNA and glomerular mesangial cell(GMC) hypertrophy in cultured rat GMC.Methods Cultured rat 1097 GMCs were divided into high glucose group, mannitol group, different insulin concentration groups, high glucose plus different insulin concentration groups and control group. Semi quantity RT PCR and flow cytometery were used to detect GLUT 4mRNA and p21mRNA levels and GMC volume. Results A certain expression of GLUT 4mRNA and p21mRNA from GMC was found in control group. High glucose decreased GLUT 4mRNA level and increased p21mRNA level. Insulin up regulated GLUT 4mRNA expression in a dose dependent manner.The more p21mRNA expressed, the stronger forward scatter (FSC) was and the bigger GMC became. Conclusions High glucose can cause GMC hypertrophy. Up regulation of p21mRNA and down regulation of GLUT 4mRNA may be involved in GMC hypertrophy and glomerular hypertrophy in early diabetic nephropathy.

Effect of tunicamycin-inhibitor of N-oligosaccharide chain on glomerular mesangial cells / 中华肾脏病杂志

Objective To investigate the effects of tunicamycin(TM)-inhibitor of N-glycosylation of proteins on proliferation and apoptosis of glomerular mesangial cells(GMC) and synthesis of FN. Methods Morphology of GMC apoptosis was observed under eletron microscopy, and flowcytometry was used for assessing apoptosis rate. GMC proliferation was examined by MTT assay. The amount of FN was measured by ELISA. Results TM inhibited the proliferation of GMC as compared with untreated controll ( P