Relationship Between Endogenous Hydrogen Sulfide and Pulmonary Vascular Indexes on High-Resolution Computed Tomography in Patients with Chronic Obstructive Pulmonary Disease.

Objective: To explore the relationship between endogenous hydrogen sulfide (H2S) and high-resolution computed tomography (HRCT) indexes in pulmonary vascular remodeling. Methods: A total of 94 stable chronic obstructive pulmonary disease (COPD) patients were recruited for the study．Plasma H2S levels were measured using fluorescence probe. Fluorescence quantitative polymerase chain reaction was used to measure H2S synthase cystathionine-γ-lyase (CSE) mRNA and cystathionine-ß-synthesis enzyme (CBS) mRNA. The main pulmonary artery diameter (mPAD), axial diagonal mPAD, coronal mPAD, sagittal mPAD, right pulmonary artery diameter (RPAD), left pulmonary artery diameter (LPAD), and ascending aortic diameter (AAD) and the percentage of total cross-sectional area of vessels less than 5 mm2 of total lung area (%CSA <5) on HRCT were measured. Pulmonary arterial systolic pressure (PASP) of echocardiography, blood gas analysis, and routine blood tests were performed. Correlation analysis and multivariate linear regression were performed using SPSS 22.0. Results: H2S was negatively correlated with mPAD, axial diagonal mPAD, and sagittal mPAD (r = -0.25~-0.32) and positively correlated with PaO2 (r = 0.35). Relative expression of CSE mRNA was positively correlated with PASP, coronal mPAD, sagittal mPAD, white blood cell count (WBC), and neutrophil count (N) (r = 0.30~0.44). The relative expression of CBS mRNA was positively correlated with PASP, WBC, and N (r = 0.34~0.41). In separate models predicting pulmonary vascular indexes, a 1µmol/L increase in H2S predicted lower pulmonary artery diameter (for axial diagonal mPAD, 0.76mm lower; for mPAD/AAD, 0.68mm lower). All P values were less than 0.05. Conclusion: Endogenous H2S may be involved in pulmonary vascular remodeling, providing a new method for the diagnosis and treatment of COPD. The generation of H2S may be inhibited by hypoxia, inflammation, etc.

Effects of angiotensin-converting enzyme inhibitors and angiotensin receptor blockers on left ventricular mass index and ejection fraction in hemodialysis patients: A meta-analysis with trial sequential analysis of randomized controlled trials.

BACKGROUND: Angiotensin-converting enzyme inhibitor (ACEI) and angiotensin receptor blocker (ARB) are effective therapies for left ventricular hypertrophy and heart failure. We aimed to assess the efficacy of ACEI and ARB in hemodialysis patients. METHODS: The MEDLINE, EMBASE, and Cochrane Library databases were searched to identify studies published before December 2015 that investigated the use of ACEI or ARB compared with controls to determine the effect on the left ventricular mass index (LVMI) and ejection fraction (EF) in hemodialysis patients, and trial sequential analysis was also performed for outcomes. RESULTS: A total of 357 cases of patients involved in 8 clinical trials (nine comparisons) were included. Compared with controls, ACEI/ARB treatment resulted in more effective improvement of LVMI in hemodialysis patients (weighted mean difference (WMD) -14.42, 95% confidence interval (CI) -20.89 to -7.95), and the cumulative z curve crossed the trial sequential monitoring boundary for benefit in trial sequential analysis. Although ACEI/ARB and controls did not show significant differences with regards to EF (WMD: -0.84, 95% CI: -2.91 to 1.24). CONCLUSIONS: The comparison between ACEI/ARB and controls showed that the former type of drug causes a greater reduction in LVMI with hemodialysis patients, although they have no significant impact on the EF. Compared with other antihypertensive drugs or placebo, ACEI/ARB is recommended as a better choice in hemodialysis patients.

Metabolic changes of H2S in smokers and patients of COPD which might involve in inflammation, oxidative stress and steroid sensitivity.

Oxidative stress and inflammation play crucial role in the pathogenesis of chronic obstructive pulmonary disease (COPD). Most patients with COPD show a poor response to corticosteroids. Hydrogen sulfide (H2S ) has been implicated in the pathogenesis of COPD, but its expression and effects in lung tissue from COPD patients are not clear. In peripheral lung tissue samples from 24 patients, we found that compared with nonsmokers, the protein level of cystathionine-γ-lyase (CSE) was decreased in smokers and COPD patients. CSE mRNA increased but cystathionine-ß-synthase (CBS) mRNA decreased in COPD patients. H2S donors increased glutathione and superoxide dismutase in CS exposed U937 cells and inhibited CS-induced TNF-α and IL-8 secretion. Dexamethasone alone had no effect on lipopolysaccharide (LPS) induced TNF-α release by alveolar macrophages from CS exposed rats, however the combination of dexamethasone and H2S donor significantly inhibited TNF-α release. Thus, H2S metabolism is altered in lung tissue of smokers and COPD patients. Supplementation of H2S protects against CS-induced oxidative stress and inflammation in macrophages and H2S on steroid sensitivity deserves further investigation.

Mechanisms of hypercoagulability in nephrotic syndrome associated with membranous nephropathy as assessed by thromboelastography.

INTRODUCTION: Thromboelastography (TEG) was performed to assess potential hypercoagulability in Nephrotic syndrome (NS) patients with membranous nephropathy (MN) and to explore correlated factors contributing to hypercoagulable status MATERIALS AND METHODS: 101 MN patients, 61 minimal change disease (MCD) patients and 20 healthy controls met the inclusion criteria. The MN and MCD patients were stratified into two layers according to serum albumin (SALB) levels (<20g/l or 20-30g/l). Primary outcome measures included reaction time (R), α-angle, maximum amplitude (MA) and coagulation index (CI). TEG parameters of four patient subgroups were analyzed in factorial designed ANOVA with factors disease and SALB. RESULTS: By linear regression analysis, TEG parameters in MN patients correlated with SALB (P<0.01) and the ANOVA for factorial designed data confirmed that the main effects of factors SALB and disease were both statistically significant. Besides, comparison between control group and patient subgroups showed that R value in normal controls was significantly higher than that in MN subgroups, but was not statistically different from that in MCD subgroups. NS patients (MCD, MN) had significantly higherα-angle, MA and CI values than healthy controls (p<0.05). CONCLUSIONS: MN patients tend to be more hypercoagulable than normal and MCD patients. Hypercoagulability in MN patients involves the whole thrombotic processes acceleration (activated intrinsic pathway, fibrinogen, platelet function and fibrin-platelet interaction), whereas hypercoagulable state in MCD patients may be that the coagulation factors are not fully activated. Greater efforts should be made to prevent hypercoagulability especially for MN patients with severe hypoalbuminemia.

A meta-analysis of the effects of angiotensin converting enzyme inhibitors and angiotensin II receptor blockers on insulin sensitivity in hypertensive patients without diabetes.

AIMS: This study sought to compare the effects of angiotensin converting enzyme inhibitors (ACEI) and angiotensin receptor blockers (ARB) on insulin sensitivity (IS) in hypertensive patients without diabetes. METHODS: Studies on the observation of IS in hypertensive patients without diabetes who received ACEI and ARB prior to December 2013 was collected using computer-based retrieval of the PUBMED, EMBASE, and COCHRANE databases. The primary indicators included IS, fasting plasma glucose (FPG), and fasting plasma insulin (FPI). The secondary indicators included systolic blood pressure (SBP) and diastolic blood pressure (DBP). A meta-analysis was performed using the STATA and Review Manager 5.2 software. The effects of these two drugs on IS in hypertensive patients without diabetes were analyzed using the fixed effect model and the random effect model. RESULTS: A total of 203 cases of patients involved in 4 clinical studies were included. As compared to ARB, ACEI treatment resulted in more effective improvement of IS in hypertensive patients without diabetes (SMD: 0.45, 95% CI 0.17-0.73), although these two drugs did not show significant differences with regards to FPG (WMD: 0.00, 95% CI -0.19-0.20), FPI (WMD: -0.34, 95% CI -1.31-0.63), SBP (WMD: 2.85, 95% CI -1.55-7.24), and DBP (WMD: 0.81, 95% CI -1.12-2.75). CONCLUSION: In patients showing no significant difference in blood pressure control, the comparison between ACEI and ARB showed that the former type of drug more effectively relieved IS in hypertensive patients without diabetes.

A meta-analysis of the effect of angiotensin receptor blockers and calcium channel blockers on blood pressure, glycemia and the HOMA-IR index in non-diabetic patients.

OBJECTIVE: This study compared the efficacy of angiotensin receptor blockers (ARBs) and calcium channel blockers (CCBs) in the effect of insulin resistance (IR) as assessed using the homeostasis model assessment of insulin resistance (HOMA-IR) in non-diabetic patients. METHODS: The MEDLINE, EMBASE, and Cochrane Library databases were searched to identify studies published before December 2012 that investigated the use of ARBs and CCBs to determine the effect on the HOMA-IR index in non-diabetics. Parameters on IR and blood pressure were collected. Review Manager 5.2 and Stata 12.0 were used to perform the meta-analysis. Fixed and random effects models were applied to various aspects of the meta-analysis, which assessed the therapeutic effects of the two types of drug using the HOMA-IR index in non-diabetic patients. RESULTS: The meta-analysis included five clinical trials. Patient comparisons before and after treatment with ARBs and CCBs revealed that ARBs reduced the HOMA-IR index (weighted mean difference (WMD) -0.65, 95% confidence interval (CI) -0.93 to -0.38) and fasting plasma insulin (FPI) (WMD -2.01, 95% CI -3.27 to -0.74) significantly more than CCBs. No significant differences in the therapeutic effects of these two types of drug on blood pressure were observed. CONCLUSION: Given that there are no significant differences in the therapeutic effects of ARBs and CCBs on blood pressure, as ARBs are superior to CCBs in their effect on the HOMA-IR index in non-diabetics, they might be a better choice in hypertension patients without diabetes.

Minimally invasive aortic valve replacement for isolated aortic valve disease: clinical analysis of 101 consecutive patients / 中华外科杂志

<p><b>OBJECTIVE</b>To review the results for minimally invasive aortic valve replacement (AVR) through a 5 cm right anterolateral thoracotomy.</p><p><b>METHODS</b>From July 2009 to September 2011, 101 consecutive patients with isolated aortic valve disease (degenerative in 37 patients, rheumatic in 21 patients, congenital in 37 patients, endocarditic in 3 patients and aorta-arteritis in 1 patients) underwent AVR through the right anterolateral thoracotomy approach in the third intercostal space with a groin incision for femoral connection of cardiopulmonary bypass. The mean age was 45.7 years (ranging from 17 to 71 years). Sixty patients were male.</p><p><b>RESULTS</b>Operations were successfully performed in all but 1 patient (1.0%) who required intraoperative conversion to full sternotomy. Mean duration of cardiopulmonary bypass time and aortic cross-clamp time was (88 ± 24) minutes and (55 ± 18) minutes, respectively. Thirty-day mortality was 1.0% (1/101), this patient was found difficult in weaning off cardiopulmonary bypass and exhibited severe coronary artery plaque, although bypass graft was carried out immediately, the patient died of severe low cardiac output syndrome finally. No blood products were needed in 83.2% patients. Follow-up was performed in all patients at an average of (16 ± 7) months postoperatively. A good recovery was obtained in all patients except one who died of multiple organ failure caused by massive cerebral infarction 38 days after surgery.</p><p><b>CONCLUSIONS</b>Minimally invasive aortic valve replacement though the right anterolateral thoracotomy approach is safe and feasible, with good cosmetic results and rapid postoperative recovery. It is worthy of clinical elective application.</p>

Repair of posterior mitral valve prolapsed: comparative study of three different approaches / 中华外科杂志

<p><b>OBJECTIVE</b>To compared outcomes of robotic mitral valve repair with those of standard sternotomy, and right anterolateral thoracotomy.</p><p><b>METHOD</b>From August 2010 to July 2011, 70 patients with degenerative mitral valve disease and posterior leaflet prolapsed scheduled for elective isolated mitral valve repair were prospectively nonrandomized to undergo mitral valve operation by standard sternotomy (n = 30), right anterolateral thoracotomy (n = 30), or a robotic approach (n = 10). There were 49 male and 21 female patients, aging from 16 to 70 years with a mean of 53.4 years. Outcomes of the three groups were compared.</p><p><b>RESULTS</b>Mitral valve repair was achieved in all patients except 1 patient in the standard group. There were no in-hospital deaths. The median operation time [(300 ± 41) min, (184 ± 20) min and (169 ± 22) min, F = 112.5, P < 0.01], cardiopulmonary bypass time [(139 ± 26) min, (82 ± 20) min and (69 ± 23) min, F = 36.8, P < 0.01], aortic cross-clamping time [(93 ± 23) min, (47 ± 10) min and (38 ± 8) min, F = 75.0, P < 0.01] were longer for robotic than standard sternotomy and right anterolateral thoracotomy. The robotic group had shortest time of mechanical ventilation time [(4.9 ± 2.1) h, (5.3 ± 4.5) h and (14.1 ± 10.2) h, F = 13.2, P < 0.01], ICU time [(15.1 ± 2.1) h, (16.4 ± 5.4) h and (28.7 ± 16.1) h, F = 11.6, P < 0.01], postoperative hospital stay time [(4.6 ± 1.0) d, (5.7 ± 1.7) d and (8.8 ± 5.1) d, F = 8.0, P < 0.01] with the lowest of drainage [(192 ± 200) ml, (215 ± 163) ml and (405 ± 239) ml, F = 7.1, P < 0.01] and ratio of the patients needed blood transfusion (0, 20.0% and 66.7%, χ(2) = 22.7, P < 0.01). Patients were followed up 6 to 17 months, with 100% completed. No patients died during follow-ups, and no moderate or more mitral regurgitation was observed. The robotic group had the shortest time of return to normal activities compared with the other two groups [(2.4 ± 0.7) weeks, (4.2 ± 1.2) weeks and (8.2 ± 1.8) weeks, F = 83.0, P < 0.01].</p><p><b>CONCLUSION</b>This study shows mitral valve repair via the right anterolateral thoracotomy and a robotic approach is safe and feasible, with good cosmetic results and rapid postoperative recovery, and is worthy of clinical selective application.</p>

Role of focal adhesion kinase in the hypoxia-induced invasion of SMMC-7721 cells / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To study focal adhesion kinase (FAK) expression in hypoxia-stressed SMMC-7721 cells and the role of FAK expression in the hypoxia-induced invasion of SMMC-7721 cells.</p><p><b>METHODS</b>SMMC-7721 cells were cultured in 21% O2 or 1% O2. FAK expression was determined by Western blot. The siRNA expression vector pshRNA-FAK targeting to FAK and the control vector pGensil-2 were transfected into SMMC-7721 cells. The hypoxia-induced migration and invasion ability of SMMC-7721 cells transfected with pshRNA-FAK were analyzed. In normoxia, invasion of SMMC-7721 cells transfected with pcDNA3-FAK was analyzed.</p><p><b>RESULTS</b>The expression of FAK was increased significantly in SMMC-7721 cells 24 h after hypoxia stress (P<0.01). The level of FAK protein was decreased by 74.6%+/-5.1% after the pshRNA-FAK transfection in normoxia and hypoxia. The migration and invasion of SMMC-7721 cells was increased in 1% O2 (P<0.01). However, the migration and invasion of SMMC-7721 cells transfected with pshRNA-FAK was decreased in 1% O2 (P<0.05). Overexpression of FAK significantly stimulated the invasion of SMMC-7721 cells.</p><p><b>CONCLUSION</b>Up-regulation of FAK may play an important role in the invasion of SMMC-7721 cells induced by hypoxia.</p>

Hypoxia induces heat shock protein HSP70-2 expression in a HIF-1 dependent manner / 中华肝脏病杂志

<p><b>OBJECTIVES</b>To investigate role of hypoxia inducible factor 1 (HIF-1) in the transcriptional activation of heat shock protein 70-2 (HSP70-2) in hepatocellular carcinoma (HCC) cells under hypoxic conditions.</p><p><b>METHODS</b>HCC cells were exposed to reduced oxygen atmosphere (1% O2), or treated with YC-1 or HIF-1 alpha siRNA, the expression of HIF-1 alpha and HSP70-2 were detected by Western blot analysis. Serial deletions of the HSPA2 promoter were cloned in the reporter pGL3-Basic plasmid. These reporter plasmids were co-transfected with HIF-1 alpha siRNA, and the promoter activities were detected with the dual luciferase assay.</p><p><b>RESULTS</b>Western blot analysis showed that both HIF-1 alpha and HSP70-2 proteins were strongly increased after HCC cells were exposed to hypoxic conditions (1% O2) for 6 h, and the expression level of HSP70-2 was increased in a time-dependent manner. Treatment of HepG2 cells with YC-1 or HIF-1 alpha siRNA significantly inhibited the expression of HIF-1 alpha and HSP70-2. In silico analysis of the HSP70-2 promoter using the Gene2 Promoter software revealed the presence of two putative hypoxic response element (HRE) consensus at -446bp (HRE1) and -238bp (HRE2). Depletion of promoter sequence between -653 and -385 led to a dramatic reduction of promoter activity, whereas further deletion to position -201 did not reduce the activity further. These data suggested that HRE1 plays an important role in hypoxia-induced activation of the HSPA2 promoter. Site-directed mutagenesis further confirmed these results. Mutation of HRE1 but not of HRE2 abrogated the sensitivity of the HSP70-2 promoter to hypoxia.</p><p><b>CONCLUSIONS</b>HSP70-2 expression is up-regulated in response to hypoxia and a HIF-1 binding site (HRE1) in the HSP70-2 promoter is involved in this response.</p>

Inhibition of integrin-linked kinase via a siRNA expression plasmid attenuates connective tissue growth factor-induced human proximal tubular epithelial cells to mesenchymal transition.

BACKGROUND: Increasing evidence suggests that connective tissue growth factor (CTGF) is involved in the epithelial-to-mesenchymal transition (EMT). The exact intracellular events that drive this process, however, are not fully understood. In this study, we investigated the role of integrin-linked kinase (ILK) in mediating CTGF-induced EMT. METHODS: The expression of alpha-smooth muscle actin (alpha-SMA) and E-cadherin upon the stimulation by recombinant human CTGF (rhCTGF) in cultured human tubular epithelial cell line (HK-2) was detected by real-time RT-PCR and Western blot. Subsequently, the role of ILK was determined by using ILK siRNA. RESULTS: rhCTGF increased the mRNA expression of alpha-SMA significantly in a dose- and time-dependent manner, while E-cadherin mRNA decreased in a dose- and time-dependent manner. alpha-SMA protein was up-regulated after stimulation by 5 ng/ml CTGF for 96 h, and increased further after stimulation by 50 ng/ml. An immunocytochemical study showed that alpha-SMA was initially detectable at 48 h, and increased further at 72 h, while there was almost no alpha-SMA immunostaining observed in the control group at the same time point. E-cadherin protein was also down-regulated in a dose-dependent manner. Transfection of HK-2 cells with ILK-siRNA significantly attenuated rhCTGF-induced alpha-SMA induction and E-cadherin repression. CONCLUSION: Our study suggested that ILK mediated the effect of EMT in proximal tubular epithelial cells stimulated by CTGF.

Inhibition of HSP70-2 expression by RNA interference induces apoptosis of human hepatocellular carcinoma cells / 中华肝脏病杂志

<p><b>OBJECTIVES</b>To determine the effect of short hairpin RNA targeting HSP70-2 on the growth and apoptosis of hepatocellular carcinoma (HCC) cells, and to elucidate its possible mechanisms in mitochondria apoptotic pathway.</p><p><b>METHODS</b>Western blot and immunocytochemistry were used to determine the expression of HSP70-2 in HCC cells and normal hepatocytes. HepG2 and Huh-7 cells were cultured and transfected with HSP70-2 shRNA1 and shRNA2. Cell proliferation was examined by MTT. Cell apoptosis and mitochondria membrane potential were determined by flow cytometry. Western blot was used to analyze the expressions of apoptosis related proteins including Bax, Bcl-2, PARP, caspase-9 and caspase-3.</p><p><b>RESULTS</b>HSP70-2 was expressed at high levels in hepatocellular carcinoma (HCC) cells (SNU-449, HepG2, Huh-7, Hep3B) whereas there were very low levels in normal hepatocytes (L02). Using DNA vector-based RNA interference, we found that knockdown of HSP70-2 inhibited the growth of HCC cells through induction of mitochondria-dependent apoptosis. The mitochondria-dependent apoptosis induced by HSP70-2 knockdown was indicated by cytochrome c release from mitochondria, activation of caspase-9 and caspase-3, and loss of mitochondrial potential. Furthermore, knockdown of HSP70-2 resulted in up-regulation of the pro-apoptotic factor Bax and down-regulation of the pro-survival factor Bcl-2.</p><p><b>CONCLUSIONS</b>Our results indicated that HSP70-2 down-regulation induces apoptosis of HCC cells through the mitochondrial apoptotic pathway, highlighting the importance of HSP70-2 in survival of HCC cells and maintenance of liver function.</p>

Epithelial to mesenchymal transition in the progression of tubulointerstitial fibrosis.

OBJECTIVE: To review the mechanisms of epithelial to mesenchymal transition (EMT) and its role in the progression of tubulointerstitial fibrosis. DATA SOURCES: The data used in this review were obtained mainly from the studies of EMT reported from 2000-2006. STUDY SELECTION: Relevant articles on studies of EMT in tubulointerstitial fibrosis were selected. Data were mainly extracted from the 45 articles listed in the reference section of this review. RESULTS: The process of EMT has gained wide recognition as candidate mechanism in progression of chronic fibrotic disorders. New markers were identified and facilitate the observation of EMT. EMT is regulated by many factors through activation of kinase-dependent signaling cascades. Recent findings suggest that EMT is a reversible process, which can be controlled by factors for their epithelial inducing activities. CONCLUSION: Remarkable progresses of EMT research have been made recently. Preventing or reversing EMT is a promising strategy against renal fibrosis.

Role of ERK1/2 and PI3-K in the regulation of CTGF-induced ILK expression in HK-2 cells.

BACKGROUND: Previous studies revealed that integrin-linked kinase (ILK), an intracellular serine/threonine protein kinase, is a critical mediator for tubular epithelial to mesenchymal transition (EMT), and likely plays an important role in the pathogenesis of chronic kidney fibrosis. However, the exact signal pathway has not been well understood. In this study, we investigated the role of extracellular regulating kinase 1/2 (ERK1/2) and phosphatidylinositol 3-kinase (PI3-K) in the regulation of ILK expression by connective tissue growth factor (CTGF) in HK-2 cells. METHODS: Experiments were performed on transformed (human kidney cell (HKC)-clone 2) human proximal tubular epithelial cells (PTECs). Induction of ILK in response to CTGF was studied at the mRNA level by real-time PCR and protein by immunoblotting. Chemical inhibitors were used to assess the role of MEK/ERK1/2, PI3-K, and P38 MAPK signaling pathways in induction of ILK by CTGF. RESULTS: CTGF induced ILK protein expression in HK-2 cells in a time- and dose-dependent manner. There was a 5.638-fold (control: 1.000+/-0.290, 50 ng/ml: 5.638+/-1.200; *P<0.05 vs. control) and 5.740-fold (0 h: 1.000+/-0.498, 48 h: 5.740+/-1.465, *P<0.05 vs. control) increase compared to control respectively. CTGF-induced ILK expression was partially reduced by inhibiting ERK1/2 and PI3-K activation. There was no influence of ILK expression by inhibiting P38 MAPK activation when cells treated with CTGF. CONCLUSION: CTGF induces the expression of ILK protein in HK-2 cells. This induction is partially dependent on MEK/ERK1/2 and PI3-K signaling pathways. Inhibiting CTGF-induced ILK by targeting PI3-K and/or MEK/ERK1/2 signaling pathways could be of therapeutic value in renal fibrosis.

Influence of connective tissue growth factor antisense oligonucleotide on angiotensin II-induced epithelial mesenchymal transition in HK2 cells.

AIM: The present study was designed to further investigate the effect of connective tissue growth factor antisense oligonucleotide (CTGF-AS) on angiotensin II (Ang II)-induced tubular cell epithelial mesenchymal transition (EMT) in vitro. METHODS: The human proximal tubular cell line (HK2) was grown in Dulbecco's modified Eagle's medium containing 10% heat inactivated fetal calf serum. After being rested in serum-free medium for 24 h, the influence of CTGF-AS (20 mug/mL) on Ang II-induced (0.1 micromol/L) CTGF mRNA and the protein expression were examined by using reverse transcription-polymerase chain reaction and indirect-immunofluorescence. The effect of CTGF-AS on Ang II-induced cellular ultrastructure was observed using a transmissive electronic microscope. The expression of alpha-smooth action (alpha-SMA) was assayed by immunocytochemistry. In all experiments, the control group was treated with scrambled oligonucleotide. RESULTS: It was shown that Ang II significantly induced the increasing expression of CTGF mRNA and protein (P<0.01, respectively), which were significantly abolished by treatment with CTGF-AS. After stimulating cells with Ang II, the cellular ultrastructure showed mesenchymal features. These effects were partially inhibited by CTGF-AS. Ang II significantly resulted in the expression of alpha-SMA in time dependent manner, which was markedly attenuated by the treatment with CTGF-AS (P<0.01, respectively). In contrast, no similar effects were observed in the control group treated with scrambled oligonucleotide. CONCLUSION: Ang II-induced EMT in human proximal tubular epithelial cells (PTC) can be attenuated by treatment with CTGF-AS. Our data provides further evidence that CTGF might be involved in Ang II-induced EMT in PTC.

Role of connective tissue growth factor (CTGF) module 4 in regulating epithelial mesenchymal transition (EMT) in HK-2 cells.

BACKGROUND: Recent studies have suggested that connective tissue growth factor (CTGF) plays a key role in tissue fibrosis including renal scarring. While studies showed several forms of CTGF with 10-38 kDa in the body fluids, little is known about these small molecule species. We investigated the effect of a 10 kDa CTGF molecule consisting of module 4, on the epithelial mesenchymal transition (EMT) in human proximal tubular cell line (HK-2). METHODS: HK2 cells were cultured in DMEM medium. The response of cytokeratin (CK) and vimentin (VIM) mRNA and protein expression to the stimulation of rhCTGF(C) were observed by real-time PCR and immunocytochemistry. At the same time, the morphologic changes were observed by microscopy, and expression of alpha-smooth muscle actin (alpha-SMA) and fibronectin (FN) was detected by laser confocal microscope. These effects were compared with CTGF N-terminal [rhCTGF(N)], consisting of module 1-3, and observed in a condition with the addition of anti-CTGF antibody. RESULTS: RhCTGF(C) induced striking changes in epithelial cells, including changes in cellular morphology, loss of CK, gain VIM and alpha-SMA, and increased levels of fibronectin. Cocultured with anti-CTGF antibody could abrogate most of these effects, while cells treated with rhCTGF(N) showed no significant phenotypic changes comparing to control group. CONCLUSIONS: Our results suggest that module 4 could induce HK-2 cells EMT, whereas the residual fragment has no similar effect in spite of consisting of 3 modules of CTGF molecule.