BACKGROUND/AIMS: Vascular access dysfunction is an important cause of morbidity and mortality in hemodialysis (HD) patients. Recent studies have shown that a klotho gene mutation is related to endothelial dysfunction, thrombosis, and arteriosclerosis, which are regarded as causes of vascular access dysfunction. We investigated the relationship between the klotho G-395A polymorphism and early dysfunction in vascular access in HD patients. METHODS: Patients who underwent vascular access operations between 1999 and 2002 were enrolled (n=126). Genotyping was performed by allelic discrimination using a 5'-nuclease polymerase chain reaction assay. Clinical data that could be relevant to access dysfunction were obtained from medical records. Early dysfunction of vascular access was defined as the need for any angioplastic or surgical intervention to correct or replace a poorly or nonfunctioning vascular access within 1 year and at least 8 weeks after initial access placement. RESULTS: Of the 126 patients, the genotype frequency of G-395A was 72.2% for GG (n=91), 24.6% for GA (n=31), and 3.2% for AA (n=4), and the frequency of minor allele was 0.155. Clinical data were similar between the two groups, divided according to the status of the A allele. Early dysfunction occurred in 34 (27.0%) of patients, but it occurred at a significantly higher rate in A allele carriers (45.7%, 16/35) than in noncarriers (19.8%, 18/91; p=0.003). CONCLUSIONS: Our results suggest that the klotho G-395A polymorphism could be a risk factor for early dysfunction of vascular access in HD patients.
Aged ; *Arteriovenous Shunt, Surgical ; Catheters, Indwelling ; Cohort Studies ; Female ; Glucuronidase/*genetics ; Humans ; Kidney Failure, Chronic/complications/*genetics/therapy ; Male ; Middle Aged ; Polymorphism, Genetic/*genetics ; Promoter Regions, Genetic/genetics ; *Renal Dialysis ; Vascular Diseases/complications/genetics ; Vascular Patency/*genetics

The NLRP3 inflammasome, a protein complex belonging to the family of nucleotide-binding and oligomerization domain like receptors (NLRs), plays a vital role in the innate immune system. It promotes pro-caspase 1 cleavage into active caspase-1, which contributes to maturation and releases of IL-1β and IL-18 in response to the harmful signals and participates in the host immune response and sterile inflammation. Recently a large number of studies have shown that NLRP3 inflammasome closely relates to the pathogenesis of the vascular diseases. NLRP3 inflammasome, which involves in the sterile inflammation of the vascular wall, plays an important role in the pathogenesis of main, middle and small arteries.
Caspase 1 ; immunology ; metabolism ; Gene Expression Regulation ; genetics ; immunology ; Humans ; Inflammasomes ; immunology ; Inflammation ; complications ; genetics ; Interleukin-18 ; genetics ; immunology ; Interleukin-1beta ; genetics ; immunology ; NLR Family, Pyrin Domain-Containing 3 Protein ; immunology ; Signal Transduction ; genetics ; immunology ; Vascular Diseases ; etiology ; genetics ; immunology

OBJECTIVEVascular endothelial growth factor (VEGF) contributes to lung development and recovery of lung structure from lung injury. This study aimed to explore the changes of expression of VEGF protein and mRNA in neonatal rats following hyperoxic lung injury.

METHODSForty-eight Sprague-Dawley neonatal rats were randomly continually exposed to hyperoxia (FiO2=95%) or to room air (FiO2=21%, control group) 30 minutes after birth. VEGF protein and mRNA expression in the lungs was determined by immunohistochemical methods and reverse tanscription polymerasechain reaction (RT-PCR) respectively 3,7 and 14 days after birth.

RESULTSVEGF protein and mRNA expression increased with increasing postnatal age in the control group. In the hyperoxia exposure group VEGF protein expression decreased markedly at 7 days (7.79+/-5.23 vs 12.67+/-3.82; P<0.01) and 14 days of hyperoxia exposure (5.85+/-3.37 vs 15.10+/-8.91; P<0.01) compared with the controls. VEGF mRNA expression in the hyperoxia exposure group was significantly reduced from 3 days (0.78+/-0.22 vs 1.19+/-0.63) through 14 days of hyperoxia exposure (0.48+/-0.12 vs 1.89+/-0.81) compared with the controls (P<0.01).

CONCLUSIONSVEGF is associated with lung development in neonatal rats. Hyperoxia exposure can decrease VEGF protein and VEGF mRNA expression in the lungs of neonatal rats. VEGF might be involved in the pathogenesis of hyperoxic lung injury.

Animals ; Animals, Newborn ; Female ; Hyperoxia ; complications ; Lung ; chemistry ; metabolism ; Lung Diseases ; etiology ; metabolism ; Male ; RNA, Messenger ; analysis ; Rats ; Rats, Sprague-Dawley ; Vascular Endothelial Growth Factor A ; analysis ; genetics

Animals ; Fibrosis ; Genetic Testing ; Interleukin-1 ; genetics ; Kidney ; pathology ; Kidney Diseases ; complications ; diagnosis ; genetics ; Male ; Rats ; Rats, Sprague-Dawley ; Reverse Transcriptase Polymerase Chain Reaction ; Transforming Growth Factor beta ; genetics ; Ureteral Obstruction ; complications ; Vascular Cell Adhesion Molecule-1 ; genetics ; Vascular Endothelial Growth Factor A ; genetics

This study aims to explore the influence of Polygonati Rhizoma on the pyroptosis in the rat model of diabetic macroangiopathy via the NOD-like receptor thermal protein domain associated protein 3(NLRP3)/cysteinyl aspartate specific proteinase-1(caspase-1)/gasdermin D(GSDMD) pathway. The rat model of diabetes was established by intraperitoneal injection of streptozotocin(STZ) combined with a high-fat, high-sugar diet. The blood glucose meter, fully automated biochemical analyzer, hematoxylin-eosin(HE) staining, enzyme-linked immunosorbent assay, immunofluorescence, immunohistochemistry, and Western blot were employed to measure blood glucose levels, lipid levels, vascular thickness, inflammatory cytokine levels, and expression levels of pyroptosis-related proteins. The mechanism of pharmacological interventions against the injury in the context of diabetes was thus explored. The results demonstrated the successful establishment of the model of diabetes. Compared with the control group, the model group showed elevated levels of fasting blood glucose, total cholesterol(TC), triglycerides(TG) and low-density lipoprotein cholesterol(LDL-c), lowered level of high-density lipoprotein cholesterol(HDL-c), thickened vascular intima, and elevated serum and aorta levels of tumor necrosis factor-α(TNF-α), interleukin-1β(IL-1β) and interleukin-18(IL-18). Moreover, the model group showed increased NLRP3 inflammasomes and up-regulated levels of caspase-1 and GSDMD in aortic vascular cells. Polygonati Rhizoma intervention reduced blood glucose and lipid levels, inhibited vascular thickening, lowered the levels of TNF-α, IL-1β, IL-18 in the serum and aorta, attenuated NLRP3 inflammasome expression, and down-regulated the expression levels of caspase-1 and GSDMD, compared with the model group. In summary, Polygonati Rhizoma can slow down the progression of diabetic macroangiopathy by inhibiting pyroptosis and alleviating local vascular inflammation.
Animals ; Rats ; Caspase 1/genetics* ; NLR Family, Pyrin Domain-Containing 3 Protein/genetics* ; Interleukin-18 ; Blood Glucose ; Pyroptosis ; Tumor Necrosis Factor-alpha ; Diabetes Complications ; Vascular Diseases ; Inflammasomes ; Cholesterol ; Lipids ; Diabetes Mellitus

BACKGROUND: Currently, the hypertension (HTN) patients undergo appropriate medical treatment, and traditional risk factors are highly controlled. Therefore, potential risk factors of atherosclerotic vascular diseases (AVD) and venous thromboembolisms (VTE) in HTN should be reconsidered. We investigated thrombophilic genetic mutations and existing biomarkers for AVD or VTE in HTN patients receiving treatment. METHODS: A total of 183 patients were enrolled: AVD with HTN (group A, n=45), VTE with HTN (group B, n=62), and HTN patients without any vascular diseases (group C, n=76). The lipid profile, homocysteine (Hcy) levels, D-dimers, fibrinogen, antithrombin, lupus anticoagulant, and anti-cardiolipin antibody (aCL) were evaluated. Prothrombin G20210A, Factor V G1691A, and methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C were analyzed. RESULTS: All patients revealed wild type prothrombin G20210A and Factor V G1691A polymorphisms. The frequency of MTHFR polymorphisms was 677CT (n=84, 45.9%); 677TT (n=46, 25.1%); 1298AC (n=46, 25.1%); and 1298CC (n=2, 1.1%). The MTHFR 677TT genotype tended to increase the odds ratio (OR) to AVD events in HTN patients (OR 2.648, confidence interval 0.982-7.143, P=0.05). The group A demonstrated significantly higher Hcy levels (P=0.009), fibrinogen (P=0.004), and platelet counts (P=0.04) than group C. Group B had significantly higher levels of D-dimers (P=0.0001), platelet count (P=0.0002), and aCL (P=0.02) frequency than group C. CONCLUSIONS: The MTHFR 677TT genotype and Hcy level could be potential risk factors associated with development of AVD in HTN patients receiving treatment. D-dimer and aCL might be useful to estimate the occurrence of VTE in them.
Adult ; Aged ; Antihypertensive Agents/therapeutic use ; DNA/analysis ; Factor V/genetics ; Female ; Fibrin Fibrinogen Degradation Products/analysis ; Genotype ; Homocysteine/blood ; Humans ; Hypertension/*complications/drug therapy ; Lipids/blood ; Male ; Methylenetetrahydrofolate Reductase (NADPH2)/genetics ; Middle Aged ; Odds Ratio ; Platelet Count ; Polymorphism, Single Nucleotide ; Prothrombin/genetics ; Real-Time Polymerase Chain Reaction ; Republic of Korea ; Risk Factors ; Vascular Diseases/*etiology/genetics ; Venous Thrombosis/*etiology/genetics

OBJECTIVETo investigate possible mechanism of angiogenesis in brain tissue of neonatal rat hypoxic-ischemic encephalopathy (HIE).

METHODSForty seven-day old neonatal rats were randomly assigned to hypoxic-ischemic (Model group) or sham treatment (Sham group), each group had 20 rats. Five rats from each group were sacrificed on days 1, 3, 7 and 14 after hypoxia-ischemia. Paraffin sections of the brain were stained with anti-endothelial cell, anti-proliferating cell nuclear antigen (PCNA) or anti-vascular endothelial growth factor (VEGF) by using single or double immunohistochemistry. The brain capillary density index (BCDI), brain proliferating capillary density index (BPCDI) and the expression of VEGF were analyzed under the microscope. The expression of VEGF and hypoxia-inducible factor-1alpha (HIF-1alpha) mRNA in hypoxic-ischemic side of the brain was measured by RT-PCR.

RESULTSBCDI around infarct brain tissue in the model group began to rise on day 3 and remained higher than that of the sham group from day 3 to day 14 [day 3: (9.80 +/- 1.05)/HPF vs. (4.90 +/- 0.66)/HPF, P < 0.01;day 14: (13.29 +/- 3.90)/HPF vs. (6.08 +/- 1.50)/HPF, P < 0.01]. Occasional proliferating capillary was found in brain tissue of normal neonatal rats. The density of proliferating brain capillary on day 3 and day 7 of Model group [(0.54 +/- 0.15)/HPF vs. (0.90 +/- 0.25)/HPF] were significantly higher than those of Sham group [(0.12 +/- 0.05)/HPF vs. (0.13 +/- 0.07)/HPF, P < 0.01]. VEGF was mainly expressed in the cytoplasm of neurons, capillary endothelial cells and pial cells. Viable neurons and endothelial cells in the infarct areas also expressed VEGF. The expression of VEGF mRNA in hypoxic-ischemic brain tissue was significantly higher than that of normal control (P < 0.01) and temporally preceded angiogenesis. The expression of VEGF mRNA at 12 hours of HIE model was significantly higher than that of normal control (1.56 +/- 0.27 vs. 0.95 +/- 0.21, P < 0.05). It reached its peak on day 1 and day 3 (1.85 +/- 0.31 vs. 1.86 +/- 0.39), significantly higher than that of normal control (P < 0.01), and decreased by day 7 and day 14, without significant difference compared with normal control (P > 0.05). The expression of HIF-1alpha mRNA was also up-regulated after hypoxic-ischemic treatment. The expression of HIF-1alpha mRNA (1.07 +/- 0.21) was significantly higher than that of normal control (0.64 +/- 0.28, P = 0.048) at 3-hour of HIE model, reached its peak on day 1 (1.73 +/- 0.42, P < 0.01), remained at high expression level on day 3 (1.44 +/- 0.36, P < 0.05) and began to decline by day 7 and day 14 when it was not significantly different from normal control.

CONCLUSIONSAngiogenesis exists in the brain tissue of neonatal rat HIE model. Up-regulation of VEGF expression mediated by HIF-1 may play an important role in the process of angiogenesis.

Animals ; Animals, Newborn ; Brain ; blood supply ; Brain Diseases ; etiology ; genetics ; metabolism ; Disease Models, Animal ; Hypoxia-Inducible Factor 1, alpha Subunit ; Hypoxia-Ischemia, Brain ; complications ; Immunohistochemistry ; Neovascularization, Pathologic ; etiology ; RNA, Messenger ; genetics ; metabolism ; Rats ; Rats, Sprague-Dawley ; Reverse Transcriptase Polymerase Chain Reaction ; Transcription Factors ; analysis ; genetics ; Vascular Endothelial Growth Factor A ; analysis ; genetics

Recent epidemiologic studies clearly showed that early intensive glucose control has a legacy effect for preventing diabetic macrovascular complications. However, the cellular and molecular processes by which high glucose leads to macrovascular complications are poorly understood. Vascular smooth muscle cell (VSMC) dysfunction due to high glucose is a characteristic of diabetic vascular complications. Activation of nuclear factor-kappaB (NF-kappaB) may play a key role in the regulation of inflammation and proliferation of VSMCs. We examined whether VSMC proliferation and plasminogen activator inhibitor-1 (PAI-1) expression induced by high glucose were mediated by NF-kappaB activation. Also, we determined whether selective inhibition of NF-kappaB would inhibit proliferation and PAI-1 expression in VSMCs. VSMCs of the aorta of male SD rats were treated with various concentrations of glucose (5.6, 11.1, 16.7, and 22.2 mM) with or without an inhibitor of NF-kappaB or expression of a recombinant adenovirus vector encoding an IkappaB-alpha mutant (Ad-IkappaBalphaM). VSMC proliferation was examined using an MTT assay. PAI-1 expression was assayed by real-time PCR and PAI-1 protein in the media was measured by ELISA. NF-kappaB activation was determined by immunohistochemical staining, NF-kappaB reporter assay, and immunoblotting. We found that glucose stimulated VSMC proliferation and PAI-1 expression in a dose-dependent manner up to 22.2 mM. High glucose (22.2 mM) alone induced an increase in NF-kappaB activity. Treatment with inhibitors of NF-kappaB such as MG132, PDTC or expression of Ad-IkappaB-alphaM in VSMCs prevented VSMC proliferation and PAI-1 expression induced by high glucose. In conclusion, inhibition of NF-kappaB activity prevented high glucose-induced VSMC proliferation and PAI-1 expression.
Animals ; Aorta/cytology ; Cardiovascular Diseases/prevention & control ; Cell Proliferation/*drug effects ; Cells, Cultured ; Diabetes Complications/prevention & control ; Gene Expression Regulation/drug effects ; Glucose/immunology/*metabolism ; Leupeptins/pharmacology ; Male ; Muscle, Smooth, Vascular/*cytology ; Myocytes, Smooth Muscle/cytology/*drug effects/immunology/metabolism ; NF-kappa B/*antagonists & inhibitors/immunology ; Plasminogen Activator Inhibitor 1/*genetics ; Proline/analogs & derivatives/pharmacology ; Rats ; Rats, Sprague-Dawley ; Thiocarbamates/pharmacology

BACKGROUNDAdvanced oxidation protein products (AOPPs) are new uremic toxins reported by Witko-Sarsat in 1996, which are associated with the pathogenesis of atherosclerosis. However, the mechanisms by which AOPPs enhance atherosclerosis have not been fully understood. Monocyte chemoattractant protein-1 (MCP-1) is a chemokine which stimulates migration of monocytes and plays a critical role in the development of atherosclerosis. In this study, we investigated the effect of AOPPs on MCP-1 expression in cultured vascular smooth muscle cells (VSMCs).

METHODSVSMCs were cultured and then co-incubated with AOPP (200 micromol/L, 400 micromol/L) for different times with or without pretreatment with specific p38 mitogen-activated protein kinase (MAPK) inhibitor SB203580. RT-PCR and Western blott were used to detect MCP-1 mRNA and protein expression at different time points after AOPP stimulation in rat smooth muscle cells. Western blot was used to detect the expression of phosphorylated p38 MAPK.

RESULTSTreatment of VSMC with AOPPs resulted in a significant increase of the expression of MCP-1 mRNA and protein in time- and dose-dependent manner, and could activated p38 MAPK. Pretreatment of VSMCs with SB203580 resulted in a dose-dependent inhibition of AOPPs-induced MCP-1 mRNA and protein expression.

CONCLUSIONSAOPPs can stimulate MCP-1 expression via p38 MAPK in VSMCs. This suggests that AOPPs might contribute to the formation of atherosclerosis through this proinflammatory effect.

Animals ; Atherosclerosis ; etiology ; Cardiovascular Diseases ; etiology ; Cells, Cultured ; Chemokine CCL2 ; genetics ; Enzyme Activation ; Imidazoles ; pharmacology ; Kidney Failure, Chronic ; complications ; Male ; Muscle, Smooth, Vascular ; cytology ; metabolism ; Myocytes, Smooth Muscle ; metabolism ; Oxidation-Reduction ; Proteins ; metabolism ; Pyridines ; pharmacology ; RNA, Messenger ; analysis ; Rats ; Rats, Sprague-Dawley ; Uremia ; metabolism ; p38 Mitogen-Activated Protein Kinases ; physiology