Correlation between microvascular characteristics and the expression of MVD, IGF-1 and STAT3 in the development of colonic polyps carcinogenesis.

The aim of the present study was to investigate the correlation between vascular characteristics under narrow band imaging (NBI) and the expression of angiogenic factors of colorectal carcinoma and adenoma, and to evaluate the feasibility of NBI in vivo visualizing angiogenesis. Patients with colorectal polyps, which were pathologically confirmed as early carcinoma and adenoma, were recruited and examined by NBI. The vascular pattern was classified into type I (invisible or faintly visible vasculature), type II (clearly visible microvasculature that is regularly arranged in a round, oval honeycomb-like pattern) and type III (clearly visible microvasculature that is irregularly arranged in size and caliber or has irregular winding). Immunohistochemical staining was performed by cluster of differentiation (CD)34, insulin-like growth factor (IGF)-1 and signal transducer and activator of transcription 3 (STAT3). The histological results were compared with the vascular pattern under NBI. Overall, 64 sites (15 adenocarcinomas, 29 adenomas and 20 normal) from 58 patients were recruited in the study and examined by NBI. A higher proportion of adenomas (82.1%, 23/28) and adenocarcinomas (66.7%, 10/15) had vascular patterns II and III, respectively. The expression of microvessel density (MVD)-CD34 and IGF-1 in normal mucosa compared with adenomas and adenocarcinomas was significantly different (P<0.0001 and P=0.0062, respectively). MVD-CD34, IGF-1 and STAT3 expression in the sites displayed with vascular patterns I, II, and III was different significantly (P<0.0001, P=0.0010 and P=0.0055, respectively). The spearman correlation coefficient between NBI vascular pattern and MVD-CD34, IGF-1 and STAT3 expression was 0.67, 0.41 and 0.40, respectively. In conclusion, vascular-pattern analysis and the use of an NBI system may be a promising tool for evaluating angiogenesis of colorectal lesions in real-time endoscopy.

Curcumin attenuates high glucose-induced podocyte apoptosis by regulating functional connections between caveolin-1 phosphorylation and ROS.

AIM: Caveolin-1 (cav-1) is a major multifunctional scaffolding protein of caveolae. Cav-1 is primarily expressed in mesangial cells, renal proximal tubule cells and podocytes in kidneys. Recent evidence shows that the functional connections between cav-1 and ROS play a key role in many diseases. In this study we investigated whether regulating the functional connections between cav-1 and ROS in kidneys contributed to the beneficial effects of curcumin in treating diabetic nephropathy in vitro and in vivo. METHODS: Cultured mouse podocytes (mpc5) were incubated in a high glucose (HG, 30 mmol/L) medium for 24, 48 or 72 h. Male rats were injected with STZ (60 mg/kg, ip) to induce diabetes. ROS generation, SOD activity, MDA content and caspase-3 activity in the cultured cells and kidney cortex homogenate were determined. Apoptotic proteins and cav-1 phosphorylation were analyzed using Western blot analyses. RESULTS: Incubation in HG-containing medium time-dependently increased ROS production, oxidative stress, apoptosis, and cav-1 phosphorylation in podocytes. Pretreatment with curcumin (1, 5, and 10 µmol/L) dose-dependently attenuated these abnormalities in HG-treated podocytes. Furthermore, in HG-containing medium, the podocytes transfected with a recombinant plasmid GFP-cav-1 Y14F (mutation at a cav-1 phosphorylation site) exhibited significantly decreased ROS production and apoptosis compared with the cells transfected with empty vector. In diabetic rats, administration of curcumin (100 or 200 mg/kg body weight per day, ig, for 8 weeks) not only significantly improved the renal function, but also suppressed ROS levels, oxidative stress, apoptosis and cav-1 phosphorylation in the kidneys. CONCLUSION: Curcumin attenuates high glucose-induced podocyte apoptosis in vitro and diabetic nephropathy in vivo partly through regulating the functional connections between cav-1 phosphorylation and ROS.

Relationship Between Serum DNA Replication, Clinicopathological Characteristics and Prognosis of Hepatitis B Virus-associated Glomerulonephritis with Severe Proteinuria by Lamivudine Plus Adefovir Dipivoxil Combination Therapy.

OBJECTIVE: To explore the relationship between HBV DNA and the clinical manifestations, pathological types, injury severity, and prognosis with HBV-GN. METHODS: 102 patients with HBV-GN were divided into 3 groups, according to the serum titer of the HBV DNA. 24-h urine protein excretion, and other parameters were measured. Renal biopsy were performed. The association between HBV DNA and the pathological stage of membranous nephropathy was analyzed in 78 patients with HBV-MN. 24-h urine protein excretion was used for the evaluation of the prognosis, and the relationship between HBV DNA and prognosis were analyzed. RESULTS: Several findings were demonstrated with the increase of serum HBV DNA: 24-h urine protein excretion, plasma cholesterol, and triglycerides increased significantly (P%lt;0.05), while the plasma level of albumin decreased significantly (P%lt;0.05); The changes of serum creatinine, C3 and C4 were found but no statistical significance. Glomerular deposition of HBVAg increased, and the pathological injury was more severe. The clinical remission rate was lower in the high replication group after treatment as compared with the low replication group (P%lt;0.01). CONCLUSION: With the increase of serum HBV DNA, the urine protein excretion and the kidney injury were more severe, and the clinical remission rate was decreased.

Curcumin ameliorates epithelial-to-mesenchymal transition of podocytes in vivo and in vitro via regulating caveolin-1.

AIMS: Epithelial-mesenchymal transition (EMT) is recognized to play a key role in diabetic nephropathy (DN). Curcumin, the main active component of turmeric extracted from the roots of the Curcuma longa plant, has been reported for its anti-fibrotic effects in kidney fibrosis. The purpose of our study was to investigate the effects of curcumin in reversing epithelial-to-mesenchymal transition (EMT) of podocytes in vivo and in vitro. MATERIALS/METHODS: In vivo streptozotocin (STZ)-induced diabetic rats received vehicle or curcumin, and podocytes were treated with high glucose (HG) in the presence or absence of curcumin in vitro. And we investigated the effect of curcumin on HG-induced phosphorylation of cav-1 on the stability cav-1 and ß-catenin using immunoprecipitation and fluorescence microscopy analysis. RESULTS: Curcumin treatment dramatically ameliorated metabolic parameters, renal function, morphological parameters in diabetic rats. We found that HG treatment led to significant down-regulation of p-cadherin and synaptopodin, as well as remarkable up-regulation of α-SMA and FSP-1 in vivo and in vitro. Furthermore, curcumin inhibited HG-induced caveolin-1 (cav-1) Tyr(14) phosphorylation associating with the suppression of stabilization of cav-1 and ß-catenin. CONCLUSIONS: In summary, these findings suggest that curcumin prevents EMT of podocytes, proteinuria, and kidney injury in DN by suppressing the phosphorylation of cav-1, and increasing stabilization of cav-1 and ß-catenin.

Curcumin prevents diabetic nephropathy against inflammatory response via reversing caveolin-1 Tyr14 phosphorylation influenced TLR4 activation.

Inflammation is involved in the development and/or progression of diabetic nephropathy (DN). Curcumin has been reported for its anti-inflammation activity in DN. However, the mechanisms involved in the renoprotective effects of curcumin have not been clearly demonstrated. In this study, we hypothesized that curcumin affected high glucose (HG)-induced inflammation profiles in vivo and in vitro and then prevented renal injury in diabetic rats via reversing cav-1 Tyr(14) phosphorylation that influenced TLR4 activation. Streptozotocin (STZ)-induced diabetic rats received vehicle or curcumin for twelve weeks and podocytes were treated with HG in the presence or absence of curcumin in vitro. To further evaluate the effect of cav-1 phosphorylation at Tyr(14) on HG-induced podocyte inflammation response and TLR4 activation, a recombinant plasmid GFP-Cav-1 Y14F with a mutated phosphorylation site of cav-1, was transfected into cultured podocytes. In vivo, curcumin improved histological abnormalities and fibrosis of a diabetic kidney, inhibited renal inflammatory gene expression and reduced cav-1 phosphorylation at Tyr(14) and the expression of TLR4. Pretreatment of podocytes with curcumin reduced HG-stimulated production of proinflammatory cytokines, TLR4 and the phosphorylation of cav-1. But immunohistochemistry in rat kidney showed that the elevation of TLR4 expression is more evident in the renal interstitum than in the glomerulus where podocytes are located, and the possibility that the anti-inflammatory effects of curcumin on other cells in the kidney may be mediated through the same molecular pathways as in podocytes. Our study suggests that curcumin treatment ameliorates DN via inhibition of inflammatory gene expression by reversing caveolin-1 Tyr(14) phosphorylation that influenced TLR4 activation.