OBJECTIVETo study the effects of p38 MAPK signaling pathway and aldose reductase (AR) on the transforming growth factor (TGF)-β1-induced expression of fibronectin (FN).

METHODSHuman mesangial cells (HMCs) were cultured, and transfected with pCDNA3-AR. AR gene silencing was induced by small interfering RNA (siRNA). AR expression in HMCs was examined by immunofluorescence analysis. RT-PCR and real-time PCR were performed to detect the mRNA expression of AR in the HMCs and Western blotting was used to detect the protein expression of AR, FN and p38. AR inhibitors (ARIs), Sorbinil and Zopolrestat were added and co-incubated, followed by addition of TGF-β1. Western blotting was used to document protein expression of FN and p38 mitogen-activated protein kinases (p38 MAPKs) in the HMCs.

RESULTSImmunofluorescence analysis showed a stronger expression of AR in HMCs transfected with AR than that of normal HMCs and HMCs transfected with blank vector. In comparison with normal HMCs and those transfected with blank vector, HMCs transfected with AR showed stronger protein expression of FN (P<0.05). After incubation of ARIs, protein expression of FN decreased in HMCs transfected with AR (P<0.05). After stimulation of TGF-β1, FN protein expression increased in both normal HMCs and those transfected with AR (P<0.05). After preincubation with ARI, FN protein expression in HMCs transfected decreased significantly (P<0.05). After stimulation of TGF-β1, naïve HMCs showed increased expression of phosphor-p38. In contrast, HMCs preincubated with ARIs showed reduced expression of phosphor-p38, and HMCs transfected with AR showed increased expression of phosphor-p38 (P<0.05).

CONCLUSIONSAR regulates the expression of FN through the stimulation of TGF-β1, which may involve the activation of p38-MAPK signaling pathway. AR may play a role in the pathogenesis of glomerulosclerosis.

Aldehyde Reductase ; metabolism ; Cells, Cultured ; Fibronectins ; metabolism ; Humans ; MAP Kinase Signaling System ; Mesangial Cells ; metabolism ; RNA, Small Interfering ; Real-Time Polymerase Chain Reaction ; Transfection ; Transforming Growth Factor beta1 ; pharmacology ; p38 Mitogen-Activated Protein Kinases ; metabolism

BACKGROUND/AIMS: Upregulation of aldo-keto reductase 1B10 (AKR1B10) through the mitogenic activator protein-1 signaling pathway might promote hepatocarcinogenesis and tumor progression. The goal of this study was to evaluate the prognostic significance of AKR1B10 protein expression in patients with hepatocellular carcinoma after surgery. METHODS: A tissue microarray was used to detect the expression level of AKR1B10 protein in tumors from 255 patients with hepatocellular carcinoma who underwent curative hepatectomy. The impact of AKR1B10 expression on the survival of patients was analyzed. The median follow-up period was 119.8 months. RESULTS: High AKR1B10 protein expression was observed in 125 of the 255 patients with hepatocellular carcinoma (49.0%). High AKR1B10 expression was significantly associated with a lack of invasion of the major portal vein (p=0.022), a lack of intrahepatic metastasis (p=0.010), lower the American Joint Committee on Cancer T stage (p=0.016), lower the Barcelona Clinic Liver Cancer stage (p=0.006), and lower alpha-fetoprotein levels (p=0.020). High AKR1B10 expression was also correlated with a lack of early recurrence (p=0.022). Multivariate analyses of survival revealed that intrahepatic metastases and lower albumin levels were independent predictors of both shorter recurrence-free survival and shorter disease-specific survival. High AKR1B10 expression was an independent predictor of both longer recurrence-free survival (p=0.024) and longer disease-specific survival (p=0.046). CONCLUSIONS: High AKR1B10 protein expression might be useful as a marker of a favorable prognosis in patients with hepatocellular carcinoma after curative hepatectomy.
Adolescent ; Adult ; Aged ; Aldehyde Reductase/*metabolism ; Carcinoma, Hepatocellular/*metabolism/surgery ; Disease-Free Survival ; Female ; Hepatectomy ; Humans ; Immunohistochemistry ; Liver Neoplasms/*metabolism/surgery ; Male ; Middle Aged ; Prognosis ; Tumor Markers, Biological/*metabolism ; Young Adult

OBJECTIVETo optimize the hydrolysis process of linarin by response surface methodology, and to use the model of aldose reductase to study the acacetin's activity of aldose reductase inhibitory.

METHODThe model of acacetin enzyme in vitro was established by the determination of fluorescence absorption of NADPH, the inhibition rate of acacetin aldose reductase was calculated, and then the IC50 of hydrolysis was obtained. The hydrolysis process of linarin hydrolysis condition was optimized by using response surface method.

RESULTThe results indicated that the IC50 of acacetin (2.74 mg x L(-1)) was less than the IC50 of linarin (3.53 mg x L(-1)). Hydrolyzation time of 7.4 h, sulphuric acid concentration of 0.54 mol x L(-1) and the ratio of material to liquid of 3 : 1 were the optimum conditions.

CONCLUSIONHydrolyzate acacetin has preferable inhibitory activity of aldose reductase. The optimized hydrolysis condition of linarin is convenient to use with good predictability.

Aldehyde Reductase ; antagonists & inhibitors ; metabolism ; Animals ; Diabetic Retinopathy ; enzymology ; Drugs, Chinese Herbal ; chemistry ; pharmacology ; Enzyme Inhibitors ; chemistry ; pharmacology ; Flavones ; chemistry ; Glycosides ; chemistry ; pharmacology ; Glycosylation ; Humans ; Hydrolysis ; Male ; Rats ; Rats, Wistar ; Retina ; enzymology

OBJECTIVETo investigate the association of AKR1B10 expression in gastric cancer tissues with clinicopathologic features and prognosis of gastric cancer patients.

METHODSReal-time polymerase chain reaction (RT-PCR) was conducted to detect AKR1B10 mRNA expression in gastric cancer and adjacent gastric mucosa tissues (n=36). AKR1B10 protein expression was measured by immunohistochemistry in primary gastric cancer tissues (n=100) and non-tumorous gastric mucosa tissues (n=70).

RESULTSRT-PCR results confirmed that AKR1B10 was significantly down-regulated in gastric cancer tissues compared with that in paired adjacent mucosa [8.3% (3/36) vs. 91.7% (33/36), P=0.000]. Immunohistochemistry revealed that the percentage of AKR1B10 positive specimens in gastric carcinoma was lower than that in normal specimens [33.0% (33/100) vs. 92.9% (65/70), P=0.000]. The frequencies of positive AKR1B10 in patients was significantly correlated with tumor size (P=0.000), invasive depth (P=0.004), lymph node metastasis (P=0.028), distant metastasis (P=0.031) and TNM stages (P=0.000). The 5-year survival rate of positive AKR1B10 group was significantly higher as compared to negative group (60.6% vs. 32.8%, P<0.01).

CONCLUSIONThe down-regulation of AKR1B10 expression in gastric cancer may be associated with the progress of gastric cancer is suggestive of poor prognosis.

Adult ; Aged ; Aged, 80 and over ; Aldehyde Reductase ; genetics ; metabolism ; Female ; Gastric Mucosa ; enzymology ; pathology ; Humans ; Male ; Middle Aged ; Prognosis ; RNA, Messenger ; genetics ; Stomach Neoplasms ; diagnosis ; enzymology ; pathology

OBJECTIVEIsoliquiritigenin (ISL), a licorice chalconoid, is considered to be a bioactive agent with chemopreventive potential. This study investigates the mechanisms involved in ISL-induced apoptosis in human cervical carcinoma HeLa cells.

METHODSCell viability was evaluated using a 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl-tetrazolium bromide (MTT) assay. Apoptosis was determined by flow cytometry using an Annexin V-FITC Apoptosis Detection Kit. The intracellular ROS levels were assessed using a 2, 7-dichlorofluorescein probe assay. The mitochondrial membrane potential was measured with the dual-emission potential-sensitive probe 5, 5', 6, 6'-tetra-chloro-1, 1', 3, 3'-tetraethyl-imidacarbocyanine iodide (JC-1). The degradation of poly-ADP-ribose polymerase (PARP) protein, the phosphorylation of PKR-like ER kinase (PERK), the phosphorylation of the α-subunit of eukaryotic initiation factor 2 (eIF2α), the expression of the 78 kD glucose-regulated protein (GRP 78), and the activation of caspase-12 were analyzed via western blot analysis.

RESULTSISL significantly inhibited the proliferation, the increase in ROS levels and apoptotic rates of HeLa cells in a concentration-dependent manner. Moreover, ISL induced mitochondrial dysfunction, caspase activation, and PARP cleavage, which displayed features of mitochondria dependent on apoptotic signals. Besides, exposure of HeLa cells to ISL triggered endoplasmic reticulum (ER) stress, as indicated by the increase in p-eIF2α and GRP78 expression, ER stress-dependent apoptosis is caused by the activation of ER-specific caspase-12.

CONCLUSIONThe findings from our study suggest that ISL-induced oxidative stress causes HeLa cell apoptosis via the mitochondrion-dependent and the ER stress-triggered signaling pathways.

Aldehyde Reductase ; antagonists & inhibitors ; Apoptosis ; drug effects ; Cell Survival ; drug effects ; Chalcones ; pharmacology ; therapeutic use ; Chemoprevention ; Drug Screening Assays, Antitumor ; Endoplasmic Reticulum Stress ; drug effects ; HeLa Cells ; Humans ; Mitochondria ; drug effects ; Neoplasms ; prevention & control ; Reactive Oxygen Species ; metabolism

OBJECTIVETo study the protective effect of epalrestat against endothelial cell injuries induced by high glucose.

METHODSHuman umbilical vein endothelial cells were pretreated with epalrestat (0.1 µmol/L) for 30 min followed by exposure to high glucose for 8 h. NO concentration in the cell culture supernatant was assayed using chemiluminescence method following the exposure. Real-time PCR and Western blotting were used to detect eNOS mRNA and protein expression levels and the protein expressions of AR gene (the target gene of epalrestat) and NOX4 (the upstream gene of NO).

RESULTSCompared with mannitol treatment, an 8-h exposure to high glucose caused significantly decreased NO levels and eNOS mRNA and protein expression in the vascular endothelial cells (P<0.05). Pretreatment with epalrestat prior to high glucose exposure resulted in elevated eNOS mRNA and protein expression levels and NO up-regulation in the cell culture as compared with the glucose exposure alone group (P<0.05), causing also decreased expression of AR and NOX4 in the cells.

CONCLUSIONSHigh glucose can induce endothelial cell damage characterized by a lowered level of NO secretion. Epalrestat can protect the endothelial cells against high glucose-induced injury by inhibiting the expression of AR and NOX4.

Aldehyde Reductase ; antagonists & inhibitors ; Cells, Cultured ; Endothelium, Vascular ; drug effects ; metabolism ; Enzyme Inhibitors ; pharmacology ; Glucose ; adverse effects ; Human Umbilical Vein Endothelial Cells ; cytology ; drug effects ; Humans ; NADPH Oxidase 4 ; NADPH Oxidases ; metabolism ; Nitric Oxide Synthase Type III ; metabolism ; RNA, Messenger ; genetics ; Rhodanine ; analogs & derivatives ; pharmacology ; Thiazolidines ; pharmacology

OBJECTIVETo evaluate the aldose reductase inhibitory (ARI) activity of different fractions of Hybanthus enneaspermus for potential use in diabetic cataract.

METHODSTotal phenol and flavonoid content of different fractions was determined. ARI activity of different fractions in rat lens was investigated in vitro.

RESULTSThe results showed significant level of phenolic and flavonoid content in ethyl acetate fraction [total phenol (212.15±0.79 mg/g), total flavonoid (39.11±2.27 mg/g)] and aqueous fraction [total phenol (140.62±0.57 mg/g), total flavonoid (26.07±1.49 mg/g)] as compared with the chloroform fraction [total phenol (68.56±0.51 mg/g), total flavonoid (13.41±0.82 mg/g)] and petrolium ether fraction [total phenol (36.68±0.43 mg/g), total flavonoid (11.55±1.06 mg/g)]. There was a significant difference in the ARI activity of each fraction, and it was found to be the highest in ethyl acetate fraction [IC50 (49.26±1.76 µg/mL)] followed by aqueous extract [IC50 (70.83±2.82 µg/mL)] and it was least in the petroleum ether fraction [IC50 (118.89±0.71 µg/mL)]. Chloroform fraction showed moderate activity [IC50 (98.52±1.80 µg/mL)].

CONCLUSIONSDifferent fractions showed significanct amount of ARI activity, where in ethyl acetate fraction it was found to be maximum which may be due to its high phenolic and flavonoid content. The extract after further evaluation may be used in the treatment of diabetic cataract.

Aldehyde Reductase ; antagonists & inhibitors ; Animals ; Cataract ; drug therapy ; prevention & control ; Diabetes Complications ; drug therapy ; prevention & control ; Diabetes Mellitus ; pathology ; Flavonoids ; analysis ; Lens, Crystalline ; enzymology ; Phenols ; analysis ; Plant Extracts ; pharmacology ; Rats ; Rats, Wistar ; Violaceae ; metabolism

PURPOSE: The vascular endothelial growth factor (VEGF) expression of podocyte is one of the well-known major factors in development of diabetic nephropathy. In this study, we investigated the effects of aldose reductase inhibitor, fidarestat on diabetic nephropathy, and renal VEGF expression in a type 1 diabetic rat model. MATERIALS AND METHODS: Twenty four Sprague-Dawley male rats which were performed intraperitoneal injection of streptozotocin and normal six rats were divided into four groups including a normal control group, untreated diabetic control group, aldose reductase (AR) inhibitor (fidarestat, 16 mg.kg(-1).day(-1)) treated diabetic group, and angiotensin receptor blocker (losartan, 20 mg.kg(-1).day(-1)) treated diabetic group. We checked body weights and blood glucose levels monthly and measured urine albumin-creatinine ratio (ACR) at 8 and 32 weeks. We extracted the kidney to examine the renal morphology and VEGF expressions. RESULTS: The ACR decreased in fidarestat and losartan treated diabetic rat groups than in untreated diabetic group (24.79 +/- 11.12, 16.11 +/- 9.95, and 84.85 +/- 91.19, p < 0.05). The renal VEGF messenger RNA (mRNA) and protein expression were significantly decreased in the fidarestat and losartan treated diabetic rat groups than in the diabetic control group. CONCLUSION: We suggested that aldose reductase inhibitor may have preventive effect on diabetic nephropathy by reducing renal VEGF overexpression.
Aldehyde Reductase/*antagonists & inhibitors ; Animals ; Antihypertensive Agents/therapeutic use ; Diabetes Mellitus, Experimental/*drug therapy/*metabolism ; Diabetic Nephropathies/prevention & control ; Imidazolidines/*therapeutic use ; Kidney/*drug effects/*metabolism/pathology ; Losartan/therapeutic use ; Male ; Rats ; Rats, Sprague-Dawley ; Receptors, Angiotensin/*antagonists & inhibitors ; Vascular Endothelial Growth Factor A

OBJECTIVETo study the effect of PKC signalling pathway and aldose reductase (AR) on the expression of fibronectin (FN) induced by transforming growth factor-β1 (TGF-β1).

METHODSHuman mesangial cells (HMCs) were cultured and transfected with pcDNA3-AR, and subject to AR gene silencing with small interfering RNA (siRNA) and then the cell was treated with recombinant human TGF-β1. The AR mRNA expression in the HMCs was examined using real time RT-PCR and protein expression of AR and FN was detected by Western blotting.

RESULTSThe cultured HMC treated with TGF-β1 showed increased expression of AR and FN, the normal HMC showed not reduced expression of FN after incubation with single inhibitors of AR.Pre-incubation of cells with inhibitors of AR and PKC, then the different groups of cells were treated with TGF-β1, and the induction effect on FN expression was suppressed (34%) in HMC. HMCs transfected with AR showed a strong protein expression of FN, which was increased by 3.6-fold after treatment with TGF-β1 (P < 0.05), and the induction effect on FN expression was suppressed by GÖ6983 (42%) in HMCs (P < 0.05). The HMC with AR gene knock-down by siRNA showed a decreased expression of AR and 90% decrease of FN protein in HMCs (P < 0.01), and TGF-β1-induced up-regulation of FN was significantly suppressed by siRNA (12%) in HMCs (P < 0.01).

CONCLUSIONSAR is capable of regulating FN expression only in the presence of TGF-β1, and this reaction is possibly accomplished through the activation of PKC signalling pathway.

Aldehyde Reductase ; antagonists & inhibitors ; biosynthesis ; genetics ; Benzothiazoles ; pharmacology ; Carbazoles ; pharmacology ; Cells, Cultured ; Fibronectins ; metabolism ; Gene Knockdown Techniques ; Humans ; Indoles ; Maleimides ; Mesangial Cells ; cytology ; metabolism ; Phthalazines ; pharmacology ; Protein Kinase C ; antagonists & inhibitors ; metabolism ; RNA, Messenger ; metabolism ; RNA, Small Interfering ; genetics ; Signal Transduction ; Transfection ; Transforming Growth Factor beta1 ; pharmacology ; Up-Regulation

OBJECTIVE: To investigate the effect of cardiomyopeptidin for injection on energy metabolism in isolated hearts of young rats after ischemia-reperfusion injury. METHODS: Fifty young healthy SD rats(aged 20 +/- 3 days and weighing 50-70 g) were randomly divided into 5 groups: a normal control group (NC group, n = 10 ): the isolated hearts were stable for 20 min, and then 150 min continuous perfusion; a normal + cardiomyopeptidin group (NCMP group, n = 10): the same as the normal control group, but K-H buffer solution was added with 50 mg/L cardiomyopeptidin, and 3 ischemia-reperfusion injury model groups, including a model control group (n = 10): the isolated rat hearts were perfused with K-H buffer and then arrested with cardioplegic solution; a CMP1 group (n = 10): the ST.Thomas'II cardioplegic solution was added with 100 mg/L cardiomyopeptidin; CMP2 group (n=10): K-H buffer and ST.Thomas'II cardioplegic solution was added with 50 mg/L and 100 mg/L cardiomyopeptidin respectively. The cardiac functional indexes were monitored, including heart rate, myocardial contractility and diastolic function, peak systolic and diastole myocardial velocities and coronary flow. In the 3 ischemia-reperfusion injury model groups, myocardial ultrastructure was observed through transmission electron microscopy; the creatine kinase isoenzyme (CK-MB) concentration was measured in the fluid outflow of coronary; the content of Na+-K+ ATPase, Ca2+-Mg2+ ATPase, total ATPase, superoxide dismutase (SOD), malondialdehyde (MDA), nitric oxide(NO), total nitric oxide synthase (TNOS), inducible nitric oxide synthase (iNOS) and aldosereductase were measured in the myocardium tissue; the relative expression levels of iNOS, eNOS, and Akr1b4 mRNA in the myocardial tissue were also detected by real-time fluorescence quantitative PCR. RESULTS: In the NC group, after prolonged perfusion, the cardiac function of isolated hearts had no significant change. Cardiomyopeptidin for injection had no significant effect on normal isolated hearts. Compared with the model control group, the cardiac function indexes and coronary flow in the groups treated with cardiomyopeptidin decreased much less. Cardiac myofibrillar fragmentation and mitochondrial swelling were observed in the control group, while in the CMP groups, the myocardial structure was nearly complete, and only mild mitochondria swelling and degeneration could be seen. After the reperfusion, the content of CK-MB was increased in the control group. Compared with the model control group, the CK-MB content was lower in the CMP1 and CMP2 groups. There was a slight decline in the contents of Na+-K+ ATPase, Ca2+-Mg2+ ATPase, and Total ATPase in the CMP1 and CMP2 groups, and an increase in SOD activity (P < 0.01 or P < 0.05). The concentration of NO and MDA produced after the ischemia-reperfusion injury was much lower in the CMP1 and CMP2 groups. The activity of iNOS and aldosereductase was inhibited, the expression levels of iNOS, and Akr1b4 mRNA were significantly down-regulated in the CMP1 and CMP2 groups. These changes were more prominent in the CMP2 group (P < 0.01 or P < 0.05). The eNOS mRNA levels in the CMP2 group was up-regulated (P < 0.05). CONCLUSION Cardiomyopeptidin for injection may improve the energy metabolism, improve coronary blood flow and cardiac function after the reperfusion, thus protecting immature myocardial against ischemia-reperfusion injury in young rats. Administration of it in both K-H buffer and ST.Thomas'II cardioplegic solution is better than adding it in cardioplegic solution alone. The mechanism may be associated with the inhibition the mRNA expression of iNOS and Akr1b4 in cardiomyocytes, the inhibition activity of iNOS and aldosereductase, and the decrease of NO production.
Aldehyde Reductase ; genetics ; metabolism ; Animals ; Energy Metabolism ; drug effects ; Female ; In Vitro Techniques ; Male ; Myocardial Reperfusion Injury ; metabolism ; Myocardium ; metabolism ; ultrastructure ; Nitric Oxide ; biosynthesis ; Nitric Oxide Synthase Type II ; genetics ; metabolism ; Peptides ; pharmacology ; Random Allocation ; Rats ; Rats, Sprague-Dawley