Discovery of an EP300 Inhibitor using Structure-based Virtual Screening and Bioactivity Evaluation.

BACKGROUND: EP300 (E1A binding protein p300) played a significant role in serial diseases such as cancer, neurodegenerative disease. Therefore, it became a significant target. METHODS: Targeting EP300 discovery of a novel drug to alleviate these diseases. In this paper, 17 candidate compounds were obtained using a structure-based virtual screening approach, 4449-0460, with an IC50 of 5.89 ± 2.08 uM, which was identified by the EP300 bioactivity test. 4449-0460 consisted of three rings. The middle benzene ring connected the 5-ethylideneimidazolidine-2,4-dione group and the 3-F-Phenylmethoxy group. RESULTS: Furthermore, the interaction mechanism between 4449-0460 and EP300 was explored by combining molecular dynamics (MD) simulations and binding free energy calculation methods. CONCLUSION: The binding free energy of EP300 with 4449-0460 was -10.93 kcal/mol, and mainly came from the nonpolar energy term (ΔGnonpolar). Pro1074, Phe1075, Val1079, Leu1084, and Val1138 were the key residues in EP300/4449-0460 binding with more -1 kcal/mol energy contribution. 4449-0460 was a promising inhibitor targeting EP300, which had implications for the development of drugs for EP300-related diseases.

Association of time-averaged serum uric acid level with clinicopathological information and long-term outcomes in patients with IgA nephropathy.

Objective: Whether serum uric acid (SUA) at baseline could been identiûed as a risk factor for progression in IgA nephropathy (IgAN) patients remains unclear, therefore, long- term SUA control levels must be monitored. We aimed to investigate the relevant factors affecting time-averaged SUA (TA-SUA) and to assess the prognostic value of TA-SUA in IgAN. Methods: This retrospective study included 152 patients with IgAN. The relationships between TA-SUA and clinicopathological features and renal outcomes (defined as the doubling of the baseline serum creatinine level or end-stage renal disease) were analyzed in groups divided by quartiles of TA-SUA levels, the presence of hyperuricemia, and sex. Results: Patients with high TA-SUA levels had higher levels of baseline SUA, blood urea nitrogen (BUN), triglycerides, serum C3 and serum C4 and were more likely to be male and have hypertension, proteinuria, poor renal function, and pathological injuries including high grades of tubular atrophy/interstitial fibrosis (T1-T2). These patients had a poorer prognosis compared with patients with low TA-SUA levels. The TA-SUA level was positively correlated with baseline age and BUN, triglycerides, serum C3, and serum C4 levels, and negatively correlated with baseline eGFR. Survival curve analysis indicated that persistent hyperuricemia was associated with significantly poorer renal outcomes than normo-uricemia in both men and women. The TA-SUA level also was an independent predictor of renal outcome in patients with IgAN, with optimal cutoû values of 451.38 µmol/L (area under the curve (AUC) = 0.934) for men and 492.83 µmol/L (AUC = 0.768) for women. Conclusions: The TA-SUA level is associated with triglyceride level, complement component levels, renal function, and pathological severity of IgAN, and it may be a prognostic indicator in male and female patients with IgAN.

Acute kidney injury in patients with idiopathic membranous nephropathy: influencing factors and prognosis.

AIM: Idiopathic membranous nephropathy (IMN) is a common type of nephrotic syndrome, and is associated with acute kidney injury (AKI). We investigated the association of multiple variables with AKI in patients with IMN. METHODS: The data of 187 patients with biopsy-proven IMN were examined. Renal outcome was defined as progression to end-stage renal disease (ESRD). Binary logistic regression and Kaplan-Meier's analysis were used for statistical analysis. RESULTS: During follow-up, 46 (24.6%) patients developed AKI. The incidence of AKI was greater in males than females (p < .01). The AKI group had higher uric acid, lower serum PLA2R antibody positive, and worse baseline kidney function (all p < .01). Most patients in the AKI group had stage I (71.74%) or stage II (21.74%). The AKI group had higher renal tubular injury score and chronicity index (both p < .05). Binary logistic regression indicated that uric acid and baseline estimated glomerular filtration rate (eGFR) were independent risk factors for AKI in patients with IMN (p < .05). The optimal cutoff value of serum uric acid for predicting AKI was 402.50 µmol/L and the baseline eGFR was 96.83 mL/min/1.73 m2. Kaplan-Meier's analysis showed that the cumulative renal survival rate was lower in the AKI group (p = .047). CONCLUSIONS: AKI increases the risk of poor prognosis in IMN patients and the high uric acid and low baseline eGFR were considered independent predictors for developing AKI in patients with IMN.

Efficacy of calcitriol in treating glucocorticoidinduced osteoporosis in patients with nephrotic syndrome: an open-label, randomized controlled study.

OBJECTIVE: To evaluate the efficacy and safety of calcitriol in the prevention and treatment of glucocorticoid-induced osteoporosis. METHODS: 66 patients treated with glucocorticoids (GC) for primary nephrotic syndrome (NS) were randomly assigned to 3 groups. Groups were designated as follows: calcitriol alone (n = 22), calcitriol plus calcium carbonate (n = 23), or calcium carbonate alone (n = 21). Serum markers of bone metabolism and bone mineral density (BMD) were tested at 3 different time points: the initiation of GC treatment (baseline), 12 weeks, and 24 weeks after the initiation of treatment. RESULTS: Levels of serum 25-hydroxy vitamin D, serum osteocalcin, and total serum collagen type N-terminal extension of the peptide were significantly decreased following GC therapy (p < 0.05). ß-collagen serum-specific sequences were significantly increased following GC therapy. The above-mentioned changes were less dramatic in patients treated with calcitriol, although the differences were significant (p < 0.05). Changes in serum levels of calcium, phosphorus, alkaline phosphatase, and parathyroid hormone (PTH) were not significant. 24 weeks after the initiation of treatment, BMD of the lumbar spine and femoral bone significantly decreased in all of 3 groups. However, patients who received calcitriol had significantly higher BMD of the lumbar spine than patients who received calcium carbonate alone (calcitriol plus calcium carbonate vs. calcium carbonate alone: 0.82 ± 0.19 g/cm2 vs. 0.62 ± 0.23 g/cm2 p < 0.05; calcitriol vs. calcium carbonate alone 0.805 ± 0.203 g/cm2 vs. 0.615 ± 0.225 g/cm2 p < 0.05), respectively. No serious adverse events were observed. CONCLUSION: Calcitriol may be more effective than calcium carbonate in preventing and treating GC-induced osteoporosis in patients with NS.

[Clinical efficacy and safety of sequential treatment with alprostadil and beraprost sodium for chronic renal failure induced by chronic glomerulonephritis].

OBJECTIVE: To evaluate the clinical efficacy and safety of sequential treatment with alprostadil and beraprost sodium for chronic renal failure caused by chronic glomerulonephritis. METHODS: Sixty-three patients with chronic renal failure due to chronic glomerulonephritis, after receiving a 2-week-long conventional treatment, were randomly divided into alprostadil group (n=20, with alprostadil injection at 10 µg/d for 2 weeks), sequential treatment group (n=21, with alprostadil injection at 10 µg/d for 2 weeks and oral beraprost sodium at 20 µg three times a day for 12 weeks), and strengthened sequential treatment group (n=22, with alprostadil injection at 20 µg/d for 2 weeks and a double dose of oral beraprost sodium for 12 weeks). Urinary albumin excretion rate (UAER), cystatin C (Cys C), blood urea nitrogen, creatinine, fibrinogen, D-dimer, prothrombin time (PT), and platelets were tested before and after the treatment, and the changes in urinary albumin discharge rate, serum creatinine, and glomerular filtration rate were determined. RESULTS: The patients in strengthened sequential treatment group showed a significantly decreased change rate of urinary albumin discharge rate (P<0.01) than those in the other two groups. In the two sequential treatment groups, especially the strengthened treatment group, the change rate of glomerular filtration rate increased significantly compared with that in alprostadil group (P<0.01). Strengthened sequential treatment resulted also in significantly decreased increment of serum creatinine compared that in the other 2 groups (P<0.01). After 14 weeks of treatment, fibrinogen and D-dimer were decreased in all the 3 groups (P<0.05) to a comparable level between the 3 groups (P>0.05), and prothrombin time (PT) or platelet showed no significant changes (P>0.05). CONCLUSION: Sequential treatment with alprostadil and beraprost sodium can improve the glomerular filtration rate and decrease urine albumin excretion rate, serum creatinine increase rate, and lower blood fibrinogen and D-dimer levels, thus delaying the progression of chronic renal failure caused by chronic glomerulonephritis. This therapy shows a dose-related effect with good clinical safety.

BMP-7 blocks the cyclosporine-A-induced epithelial-to-mesenchymal transition in renal tubular epithelial cells.

AIMS: The nephrotoxic side effects of cyclosporine A (CsA) are partly due to induction of the epithelial-to-mesenchymal transition (EMT), possibly through upregulation of connective tissue growth factor (CTGF). Bone morphogenetic protein (BMP-7) has been reported to protect against and reverse renal injury via its renotropic and antifibrotic effects. We therefore designed a method to investigate the mechanism by which BMP-7 inhibits CSA-induced EMT in cultured human renal proximal tubular epithelial (HK-2) cells and whether BMP-7 can antagonize CsA-induced profibrogenic effects. METHODS: Cultured HK-2 cells were treated with CsA or a combination of CsA and BMP-7 for 72 h. Morphological changes were assessed by phase-contrast microscopy. The expression of alpha-smooth muscle actin (alpha-SMA), E-cadherin, collagen type I and CTGF was analyzed by immunofluorescence, RT-PCR, and Western blot. Additionally, the effect of CTGF silencing on CsA-mediated gene expression was assessed. RESULTS: CsA-induced EMT was associated with decreased expression of E-cadherin, increased expression of alpha-SMA, collagen type I and CTGF, and loss of epithelial morphology. BMP-7 inhibited these effects in a dose-dependent manner. Using siRNA, CTGF knock-down also attenuated EMT-associated phenotypic changes induced by CsA. CONCLUSION: These data suggest that BMP-7 can block CsA-induced EMT by downregulating the expression of CTGF, a downstream mediator of EMT.

[Effects of bone morphogenic protein-7 on transdifferentiation and the expression of connective tissue growth factor of human renal tubular epithelial cells induced by transforming growth factor-beta1].

OBJECTIVE: To investigate the effects of bone morphogenic protein (BMP)-7 upon epithelial-to-mesenchymal transition (EMT) and the expression of connective tissue growth factor (CTGF) in human renal proximal tubular epithelial cells (HK-2) induced by transforming growth factor-beta1, (TGF-beta1) and to explore the possible mechanisms of BMP-7 for the inhibition and reversal of renal interstitial fibrosis. METHODS: HK-2 cells were treated with TGF-beta1 or a combination of TGF-beta1 and BMP-7. RT-PCR and Western blot were used to determine the mRNA and protein expression of alpha-SMA, E-cadherin and CTGF. For EMT reversal experiments, when TGF-beta1-induced EMT occurred, then the medium was removed and replaced with medium containing 200 ng/ml BMP-7. After 48 h, the morphological changes and the expression of E-cadherin were assessed by phase contrast microscopy or immunofluorescent microscopy. RESULTS: The control cells displayed typical cobblestone morphology of epithelial cells. 3 ng/ml TGF-beta1 induced profound morphologic changes after 48 h, with cells becoming elongated in shape, but addition of 200 ng/ml BMP-7 for 48 h restored the epithelial morphology of HK-2 cells. Indirect immunofluorescence showed that treatment of 3 ng/ml TGF-beta1 resulted in a distinct loss of E-cadherin staining in the plasma membrane of HK-2 cells but subsequent treatment with 200 ng/ml BMP-7 largely restored the E-cadherin protein staining. 3 ng/ml TGF-beta1 significantly up-regulated the mRNA and protein expression of alpha-SMA, reduced the expression of E-cadherin and increased the expression of CTGF after 48 h (vs. control, P < 0.01). BMP-7 dramatically suppressed the mRNA and protein expression of alpha-SMA, restored the expression of E-cadherin and prevented the expression of CTGF in a dose-dependent manner after co-incubation with TGF-beta1 for 48 h (400 ng/ml BMP-7 + TGF-beta1 vs. TGF-beta1, alone, P < 0.01). CONCLUSIONS: BMP-7 exerts its antifibrotic effect partially through blocking and reversing TGF-beta1-induced EMT and downregulating the expression of CTGF in human renal tubular epithelial cells.

BMP-7 counteracts TGF-beta1-induced epithelial-to-mesenchymal transition in human renal proximal tubular epithelial cells.

BACKGROUND: A large proportion of interstitial fibroblasts actually originate from tubular epithelial cells via the epithelial-to-mesenchymal transition (EMT) in renal fibrogenesis. Transforming growth factor-beta1 (TGF-beta1) is capable of initiating and completing the entire EMT course. Bone morphogenetic protein-7 (BMP-7) is a member of the TGF-beta superfamily. Recent studies indicate that BMP-7 could reverse established renal fibrosis in mice, primarily through counteracting TGF-beta1-mediated EMT. Therefore, we tested the hypothesis that BMP-7 functions by antagonizing profibrogenic events that are induced by TGF-beta1 in cultured human renal proximal tubular epithelial (HK-2) cells. METHODS: Cultured HK-2 cells were treated with TGF-beta1 (3 ng/mL) or a combination of TGF-beta1 and BMP-7 (100-400 ng/mL) for 48 hours. Morphological changes were assessed by phase contrast microscopy. The expression of alpha-smooth muscle actin (alpha-SMA), E-cadherin, fibronectin, collagen I and connective tissue growth factor (CTGF) was analyzed by immunofluorescence, reverse transcriptase polymerase chain reaction and Western blotting. RESULTS: Incubation of HK-2 cells with 3 ng/mL TGF-beta1 for 48 hours induced EMT, in association with decreased E-cadherin expression, increased alpha-SMA, fibronectin, collagen I and CTGF expression, and loss of epithelial morphology. BMP-7 inhibited all these effects in a dose-dependent manner. In addition, 200 ng/mL BMP-7 reversed TGF-beta1-induced EMT, in association with reexpression of endogenous E-cadherin. CONCLUSIONS: These data suggest that BMP-7 attenuates progressive loss of kidney function and renal fibrosis through counteracting TGF-beta1-mediated EMT.