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Background: Next-generation sequencing of cell-free DNA (cfDNA) has been shown to be a useful noninvasive test for detecting mutations in solid tumors., Methods: Targeted gene sequencing was performed with a panel of 263 cancer-related genes for cfDNA and genomic DNA of peripheral blood mononuclear cells (PBMCs) obtained from presurgical specimens of 6 lung cancer patients, and mutation calls in these samples were compared with those of primary tumors and corresponding patient-derived xenografts (PDXs)., Results: Approximately 67% of the mutations detected in the tumor samples (primary tumors and/or PDXs) were also detected in genomic DNA from PBMCs as background mutations. These background mutations consisted of germline polymorphisms and a group of mutations with low allele frequencies, mostly <10%. These variants with a low allele frequency were repeatedly detected in all types of samples from the same patients and at similarly low allele frequency levels in PBMCs from different patients; this indicated that their detection might be derived from common causes, such as homologous sequences in the human genome. Allele frequencies of mutations detected in both primary tumors and cfDNA showed 2 patterns: 1) low allele frequencies (approximately 1%-10%) in cfDNA but high allele frequencies (usually >10% or >3-fold increase) in primary tumors and further enrichment in PDXs and 2) similar allele frequencies across samples., Conclusions: Because only a small fraction of total cfDNA might be derived from tumor cells, only mutations with the first allele frequency pattern may be regarded as tumor-specific mutations in cfDNA. Effective filtering of background mutations will be required to improve the accuracy of mutation calls in cfDNA. Cancer 2018;124:1061-9. © 2017 American Cancer Society., (© 2017 American Cancer Society.)

Protein electrophoresis is commonly used as an aid in the diagnosis of monoclonal gammopathies and is performed in many laboratories in Canada and throughout the world. However, unlike many other diagnostic tests, there is limited guidance for standardization and neither guidance nor specific recommendations for clinical reporting of serum (SPE) or urine (UPE) protein electrophoresis and immunotyping available in the literature. Therefore, a Canadian effort was undertaken to recommend standards that cover all aspects of clinical reporting with an ultimate goal towards reporting standardization. The Canadian Society of Clinical Chemists (CSCC) Monoclonal Gammopathy Interest Group (MGIG), which is composed of CSCC members with an interest in protein electrophoresis, has formed a Monoclonal Gammopathy Working Group (MGWG) to take initial steps towards standardization of SPE, UPE and immunotyping. Candidate standardization recommendations were developed, discussed and voted upon by the MGWG. Candidate recommendations that achieved 90% agreement are presented as consensus recommendations. Recommendations that did not achieve 90% consensus remain candidate recommendations and are presented with accompanying MGWG discussion. Eleven consensus recommendations along with candidate recommendations for nomenclature, protein fraction reporting, test utilization, interference handling and interpretive reporting options are presented., (Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.)

Circulating tumor cells (CTCs) enter the vasculature or lymphatic system after shedding from the primary tumor. CTCs may serve as "seed" cells for tumor metastasis. The utility of CTCs in clinical applications for sarcoma is not fully investigated, partly owing to the necessity for fresh blood samples and the lack of a CTC-specific antibody. To overcome these drawbacks, we developed a technique for sarcoma CTCs capture and detection using cryopreserved peripheral blood mononuclear cells (PBMCs) and our proprietary cell-surface vimentin (CSV) antibody 84-1, which is specific to tumor cells. This technique was validated by sarcoma cell spiking assay, matched CTCs comparison between fresh and cryopreserved PBMCs, and independent tumor markers in multiple types of sarcoma patient blood samples. The reproducibility was maximized when cryopreserved PBMCs were prepared from fresh blood samples within 2 h of the blood draw. In summary, as far as we are aware, ours is the first report to capture and detect CTCs from cryopreserved PBMCs. Further validation in other types of tumor may help boost the feasibility and utility of CTC-based diagnosis in a centralized laboratory., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Background: In this study, we developed integrative, personalized prognostic models for breast cancer recurrence and overall survival (OS) that consider receptor subtypes, epidemiological data, quality of life (QoL), and treatment., Methods: A total of 15 314 women with stage I to III invasive primary breast cancer treated at The University of Texas MD Anderson Cancer Center between 1997 and 2012 were used to generate prognostic models by Cox regression analysis in a two-stage study. Model performance was assessed by calculating the area under the curve (AUC) and calibration analysis and compared with Nottingham Prognostic Index (NPI) and PREDICT., Results: Host characteristics were assessed for 10 809 women as the discovery population (median follow-up = 6.09 years, 1144 recurrence and 1627 deaths) and 4505 women as the validation population (median follow-up = 7.95 years, 684 recurrence and 1095 deaths). In addition to the known clinical/pathological variables, the model for recurrence included alcohol consumption while the model for OS included smoking status and physical component summary score. The AUCs for recurrence and OS were 0.813 and 0.810 in the discovery and 0.807 and 0.803 in the validation, respectively, compared with AUCs of 0.761 and 0.753 in discovery and 0.777 and 0.751 in validation for NPI. Our model further showed better calibration compared with PREDICT. We also developed race-specific and receptor subtype-specific models with comparable AUCs. Racial disparity was evident in the distributions of many risk factors and clinical presentation of the disease., Conclusions: Our integrative prognostic models for breast cancer exhibit high discriminatory accuracy and excellent calibration and are the first to incorporate receptor subtype and epidemiological and QoL data., (© The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

GlyoxalaseI (GLOI) is an enzyme that catalyzes methylglyoxal metabolism. Overexpression of GLOI has been documented in numerous tumor tissues, including colorectal cancer (CRC). The antitumor effects of GLOI depletion have been demonstrated in some types of cancer, but its role in CRC and the mechanisms underlying this activity remain largely unknown. Our purpose was to investigate the antitumor effects of depleted GLOI on CRC in vitro and in vivo. RNA interference was used to deplete GLOI activity in four CRC cell lines. The cells' proliferation, apoptosis, migration, and invasion were assessed by using the Cell Counting Kit-8, plate colony formation assay, flow cytometry, and transwell assays. Protein and mRNA levels were analyzed by western blot and quantitative real-time PCR (qRT-PCR), respectively. The antitumor effect of GLOI depletion in vivo was investigated in a SW620 xenograft tumor model in BALB/c nude mice. Our results show that GLOI is over-expressed in the CRC cell lines. GLOI depletion inhibited the proliferation, colony formation, migration, and invasion and induced apoptosis of all CRC cells compared with the controls. The levels of signal transducer and activator of transcription 1 (STAT1), p53, and Bcl-2 assaciated X protein (Bax) were upregulated by GLOI depletion, while cellular homologue of avian myelocytomatosis virus oncogene (c-Myc) and B cell lymphoma/lewkmia-2 (Bcl-2) were downregulated. Moreover, the growth of SW620-induced CRC tumors in BALB/c nude mice was significantly attenuated by GLOI depletion. The expression levels of STAT1, p53, and Bax were increased and those of c-Myc and Bcl-2 were decreased in the GLOI-depleted tumors. Our findings demonstrate that GLOI depletion has an antitumor effect through the STAT1 or p53 signaling pathways in CRC, suggesting that GLOI is a potential therapeutic target.

Background: Pre-analytical errors necessitate specimen rejection and negatively affect patient safety. Our purpose was to investigate the factors leading to specimen rejection and its impact., Methods: Specimen rejections in a clinical chemistry laboratory during a 1-year period were reviewed retrospectively and analyzed for frequency, cause, circumstances, and impact., Results: Of the 837,862 specimens received, 2178 (0.26%) were rejected. The most common reasons for specimen rejection were contamination (n=764, 35.1%), inappropriate collection container/tube (n=330, 15.2%), quantity not sufficient (QNS) (n=329, 15.1%), labeling errors (n=321, 14.7%), hemolyzed specimen (n=205, 9.4%), and clotted specimen (n=203, 9.3%). The analytes most often affected were glucose (n=192, 8.8%); calcium (n=152, 7.0%), magnesium (n=148, 6.8%), potassium (n=137, 6.3%), creatinine (n=100, 4.6%), and blood urea nitrogen (n=97, 4.4%). Outpatient service and blood draw by phlebotomists were associated with low rejection rates (536/493,501 or 0.11% and 368/586,503 or 0.06%, respectively). Recollection due to specimen rejection increased the turnaround time by an average of 108min. The total cost for the recollection was around $43,210 USD with an average cost around $21.9 USD., Conclusions: The factors associated with rejection are remediable by improved training and quality assurance measures. Policies and procedures specific to specimen collection, transportation, and preparation should be strictly followed., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Methylglyoxal (MG) is a highly reactive glucose metabolic intermediate and a major precursor of advanced glycation end products. MG level is elevated in hyperglycemic disorders such as diabetes mellitus. Substantial evidence has shown that MG is involved in the pathogenesis of diabetes and diabetic complications. We investigated the impact of MG on insulin secretion by MIN6 and INS-1 cells and the potential mechanisms of this effect. Our study demonstrates that MG impaired insulin secretion by MIN6 or ISN-1 cells in a dose-dependent manner. It increased reactive oxygen species (ROS) production and apoptosis rate in MIN6 or ISN-1 cells and inhibited mitochondrial membrane potential (MMP) and ATP production. Furthermore, the expression of UCP2, JNK, and P38 as well as the phosphorylation JNK and P38 was increased by MG. These effects of MG were attenuated by MG scavenger N-acetyl cysteine. Collectively, these data indicate that MG impairs insulin secretion of pancreatic β-cells through increasing ROS production. High levels of ROS can damage β-cells directly via JNK/P38 upregulation and through activation of UCP2 resulting in reduced MMP and ATP production, leading to β-cell dysfunction and impairment of insulin production.

Liver function tests (LFTs) have been reported as independent predictors of non-liver disease-related morbidity and mortality in general population and cancer patients. In this study, we evaluated the relationship between pretreatment serum LFTs and overall survival (OS) in non-metastatic Caucasian breast cancer patients. Seven LFTs, including albumin, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, lactate dehydrogenase (LDH), total bilirubin and total protein, were measured in pretreatment serum from 2425 female Caucasian patients with newly diagnosed, histologically confirmed non-metastatic invasive breast cancer. Multivariate Cox model was used to estimate hazard ratio (HR) and 95% confidence interval (CI) for the association of individual LFTs with 5-year OS while adjusting for age, smoking status, pathological characteristics and treatment regimen. We found that serum albumin, LDH and total bilirubin were significantly associated with 5-year OS in multivariate Cox analyses. Patients with higher albumin level exhibited 45% reduced risk of death (HR = 0.55, 95% CI: 0.40-0.75) compared with those with lower albumin level. Patients with higher total bilirubin level had a nearly 40% reduction in the risk of death (HR = 0.62, 95% CI: 0.45-0.85) and patients with higher LDH levels had a 1.42-fold increased risk of death (HR = 1.42, 95% CI: 1.08-1.88). Furthermore, cumulative analysis showed a significant dose-response trend of significantly increasing risk of death with increasing number of unfavorable LFT levels. Our result highlighted the potential of using pretreatment serum levels of albumin, LDH and total bilirubin as prognostic factors for OS in patients with non-metastatic breast cancer., (© The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Through synthetic lethality screening of isogenic cell lines with and without the oncogenic KRAS gene and through lead compound optimization, we recently developed a novel anticancer agent designated NSC-743380 (oncrasin-72) that has promising in vitro and in vivo anticancer activity in a subset of cancer cell lines, including KRAS-mutant cancer cells. However, NSC-743380 tends to form dimers, which dramatically reduces its anticancer activity. To improve the physicochemical properties of NSC-743380, we synthesized a prodrug of NSC-743380, designated oncrasin-266, by modifying NSC-743380 with cyclohexylacetic acid and evaluated its in vitro and in vivo properties. Oncrasin-266 spontaneously hydrolyzed in phosphate-buffered saline in a time-dependent manner and was more stable than NSC-743380 in powder or stock solutions. In vivo administration of oncrasin-266 in mice led to the release of NSC-743380 which improved the pharmacokinetics of NSC-743380. Tissue distribution analysis revealed that oncrasin-266 was deposited in liver, whereas released NSC-743380 was detected in liver, lung, kidney, and subcutaneous tumor. Oncrasin-266 was better tolerated in mice at a higher dose level treatment (150-300 mg/kg, ip) than the parent agent was, suggesting that the prodrug reduced the acute toxicity of the parent agent. Our results demonstrated that the prodrug strategy could improve the stability, pharmacokinetic properties, and safety of NSC-743380., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Objectives: The CALIPER program recently established a comprehensive database of age- and sex-stratified pediatric reference intervals for 40 biochemical markers. However, this database was only directly applicable for Abbott ARCHITECT assays. We therefore sought to expand the scope of this database to biochemical assays from other major manufacturers, allowing for a much wider application of the CALIPER database., Design and Methods: Based on CLSI C28-A3 and EP9-A2 guidelines, CALIPER reference intervals were transferred (using specific statistical criteria) to assays performed on four other commonly used clinical chemistry platforms including Beckman Coulter DxC800, Ortho Vitros 5600, Roche Cobas 6000, and Siemens Vista 1500. The resulting reference intervals were subjected to a thorough validation using 100 reference specimens (healthy community children and adolescents) from the CALIPER bio-bank, and all testing centers participated in an external quality assessment (EQA) evaluation., Results: In general, the transferred pediatric reference intervals were similar to those established in our previous study. However, assay-specific differences in reference limits were observed for many analytes, and in some instances were considerable. The results of the EQA evaluation generally mimicked the similarities and differences in reference limits among the five manufacturers' assays. In addition, the majority of transferred reference intervals were validated through the analysis of CALIPER reference samples., Conclusions: This study greatly extends the utility of the CALIPER reference interval database which is now directly applicable for assays performed on five major analytical platforms in clinical use, and should permit the worldwide application of CALIPER pediatric reference intervals., (Copyright © 2013 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.)

Background: Apolipoprotein E (apoE) levels have been shown to be elevated in pleural effusion of patients with non-small cell lung cancer (NSCLC). However, the diagnostic value of apoE in pleural effusion in NSCLC has not been well validated and established., Methods: Samples of malignant pleural effusions (MPE) and benign effusions were collected and analyzed for apoE, tumor markers, and other biochemical changes., Results: ApoE levels were significantly higher in MPE (n=160) than in benign pleural effusions (n=40). They were higher in adenocarcinoma-associated MPE than in squamous cell carcinoma- and large cell carcinoma-associated MPE. The receiver operating characteristic curve showed that the sensitivity and specificity of apoE for the diagnosis of MPE were 87.5% and 85.3%, respectively, at the cutoff 105 ng/ml, and the area under the curve (AUC) was 0.748. For the diagnosis of adenocarcinoma-associated MPE, apoE achieved sensitivity and specificity of 70.8% and 83.30%, respectively, and the AUC was the highest of all the markers., Conclusions: ApoE levels are significantly increased in the pleural effusion of patients with NSCLC. Increased concentration of apoE in a pleural effusion is a potential marker for the diagnosis of MPE as well as for differential diagnosis of MPE in NSCLC., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Background: To study the clinical and laboratory significance of D‐lactate in the diagnosis of bacterial meningitis (BM)., Methods: The levels of D‐lactate, L‐lactate, IL-6, IL-8, and other biochemical markers were determined in 83 CSF samples from different types of meningitis and the controls., Results: The CSF values of D‐lactate, L‐lactate, IL-6, IL-8, erythrocytes, leukocytes, and protein were higher in patients with BM than those in the controls and patients with viral meningitis. The levels of D‐lactate, L‐lactate, IL-6, and erythrocytes in the BM group were higher than those in the tuberculous meningitis group. At the cutoff 12.8 μmol/l, D‐lactate showed the diagnostic sensitivity of 94.7%. D‐lactate gave the area under the curve (AUC) 0.905, which was higher than those of other markers. Using multiple marker detection, the AUC reached 0.956, which was the highest among all the parameters. Pearson correlation analysis revealed that D‐lactate was positively correlated to IL-6 and L‐lactate (r=0.727, 0.789 and P=0.000, 0.000, respectively)., Conclusions: THE CSF concentrations of D‐lactate are significantly increased in the presence of BM. Measurement of D‐lactate provides a rapid diagnosis and differential diagnosis for BM. Combination of D‐lactate with other biochemical markers improves the specificity., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Background: Pre-analytical error accounts for major total laboratory errors. We assessed the impacts of hemolysis, icterus, and lipemia on laboratory tests on Roche Cobas 6000., Methods: Various concentrations of hemoglobin, bilirubin, or Intralipid® were added into the plasma to simulate hemolytic, icteric, or lipemic samples. The analytes were then measured on Roche Cobas 6000 and the change of the analyte concentrations was determined., Results: For most of the chemistry assays, our data were in a good agreement with Roche package inserts. However some assays had significant interference at lower index values while others were affected at higher index than the Roche package inserts indicated. In addition, we observed the positive interference by hemolysis on ALT, lipase, total protein, potassium, and iron. Negative interference was noted on calcium and CK. Most of the immunoassays were not affected by hemoglobin, bilirubin, and lipids although there were a few exceptions. Several therapeutic drugs were affected either positively or negatively by hemolysis, icterus, or lipemia to a certain extent., Conclusions: We have demonstrated some test interferences which have not been reported previously on the Cobas 6000. The implementation of the cut-off indices on Cobas 6000 would provide more accurate test result reporting., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Lipoprotein-associated phospholipase A2 (Lp-PLA2) has been studied extensively in terms of biology, pathophysiology, diagnostic and prognostic values. Lp-PLA2 is an enzyme produced in atherosclerotic plaque by inflammatory cells, linked to LDL, HDL and VLDL. The binding of Lp-PLA2 to a specific lipoprotein fraction renders it more atherogenic. Increasing evidence has demonstrated Lp-PLA2 as a novel "ideal" marker for CVD as of its high specificity for vascular inflammation and low biologic variability. Thus, determination of Lp-PLA2 in individuals may provide clinically relevant information about their future risk of CVD events. In addition, Lp-PLA2 has been considered as a therapeutic target, which has been acted upon indirectly (lipid lowering medications) and directly (Lp-PLA2 antagonists such as darapladib) in pharmacologic therapies. This review will provide an overview on biochemistry, biology, proatherogenic, proinflammatory and proapoptotic effects of Lp-PLA2. Clinical utility and its validity as an independent CVD biomarker as well as a diagnostic biomarker to be detected in the very early stages of atherosclerosis will be also discussed. Moreover, the role of Lp-PLA2 as a pharmacologic therapeutic target is another theme of this review.

Objectives: To investigate the association of plasma levels of methylglyoxal (MG) and markers of inflammation/endothelial dysfunction with diabetic nephropathy (DN)., Design and Methods: Plasma levels of MG, cytokines, and adhesion molecules were measured in type 2 diabetic patients (T2DM), T2DM patients with DN, and the controls., Results: Plasma MG levels in DN were significantly higher than those in T2DM and the controls (312 ± 135 vs. 212 ± 73 and 312 ± 135 vs. 147 ± 78 nmol/L, respectively, P<0.001). The plasma levels of MG were positively correlated with the fasting glucose, HbA1c, and urinary albumin/creatinine ratio (r=0.754, P<0.05). Plasma levels of IL-6, TNF-α, and adhesion molecules were markedly increased in DN compared to T2DM patients and the controls., Conclusions: Increased plasma levels of MG, cytokines, and adhesion molecules are associated with DN. These markers may be useful in predicting the development of DN., (Copyright © 2010 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.)

Background and Aims: Evidence shows that methylglyoxal (MG), a very reactive metabolite of glucose, plays a critical role in the pathogenesis of diabetes and diabetic complications. Although soy isoflavones have beneficial effects in diabetes, the role of soy isoflavones in regulating MG levels is unknown. The present study investigates the effects of soy protein isoflavones on MG and reduced glutathione (GSH)., Methods and Results: Mild diabetes was induced in male Sprague-Dawley rats by intraperitoneal injection of 35 mg/kg streptozotocin (STZ). The diabetic rats were then randomly divided into three groups and received a special diet supplemented with casein (control), low-isoflavone soy protein (LIS), or high-isoflavone soy protein (HIS) for eight weeks, respectively. Compared to the control or LIS group, HIS diet significantly increased serum insulin levels (p<0.01 or 0.05) and reduced serum glucose and MG levels (p<0.05). Serum GSH levels were increased in HIS-fed rats compared with the control or LIS group (p<0.01). Serum total cholesterol and homocysteine levels were significantly lower in HIS and LIS rats than those of the control rats., Conclusions: Both LIS and HIS diets can lower serum lipid and homocysteine levels in this mild diabetic model. HIS diet enhances insulin secretion and reduces glucose level. Moreover, the HIS diet has potential in reducing MG and increasing GSH levels. In addition to its hypoglycemic effect, the antioxidant protection may provide beneficial effects in preventing the development of diabetic complications.

Background: Evidence suggests that transforming growth factor-beta1 (TGF-beta(1)) is associated with target organ damage in hypertension. This study aimed to investigate the relationship between TGF-beta(1) levels and kidney damage and renoprotective effects of angiotensin-converting enzyme inhibitor and/or angiotensin II type 1 receptor blocker in patients with essential hypertension (EH)., Methods: A total of 156 patients with EH were enrolled and grouped according to albumin-to-creatinine ratio (ACR). Of these, 90 patients with EH underwent a 12-week antihypertensive trial with administration of benazepril, valsartan or both. Serum TGF-beta(1), plasma angiotensin (Ang) II and urinary albumin were quantified by immunoassays., Results: Serum TGF-beta1, plasma Ang II and ACR were highly elevated in patients with EH (P < 0.01). There was a positive correlation between serum TGF-beta1 levels and ACR (r = 0.53, P < 0.01). Significant decreases in TGF beta1 and ACR were obtained in all groups at the end of 12-week antihypertensive therapy compared to the baseline values, with the combined group to a greater extent (P < 0.01). Plasma Ang II levels were significantly decreased in the benazepril group but increased in the valsartan group (P < 0.05) while no significant change was observed in the combined group., Conclusions: TGF-beta(1) is highly elevated and strongly associated with urinary albumin excretion in patients with EH. Treatment with benazepril or valsartan attenuates serum TGF-beta(1) levels and microalbuminuria with the combined therapy receiving the greater effect. TGF-beta(1) could be a potential surrogate marker in monitoring the development and progression of kidney damage in EH.

Objective: To determine the effect of methylglyoxal (MG) on cytokine production by, and apoptosis of, neutrophils from type 2 diabetes mellitus (T2DM) patients., Design and Methods: The levels of plasma MG, cytokines released by isolated neutrophils and the apoptotic status of neutrophils were determined., Results: The higher level of plasma MG in T2DM patients was correlated positively with glycated hemoglobin levels, fasting plasma glucose levels and urine albumin/creatinine ratios. The basal levels of cytokines released from neutrophils were markedly higher in patients. MG treatment of the neutrophils isolated from diabetic patients either did not alter, or decreased, the production of cytokines. In contrast, MG induced the release of cytokines from neutrophils of non-diabetics. Moreover, the neutrophils from T2DM patients showed a greater proclivity for apoptosis, which was further increased by in vitro MG treatment., Conclusion: MG stimulated neutrophils to release more cytokines, which might play a role in the development of infection in T2DM.

Endogenous hydrogen sulfide (H(2)S), generated from homocysteine metabolism mainly catalyzed by cystathionine gamma-lyase (CSE), possesses important functions in the cardiovascular system. In this study, we investigated the role of H(2)S during the pathogenesis of neointimal formation induced by balloon injury in rats. CSE mRNA levels were reduced by 86.5% at 1 week and 64.0% at 4 weeks after balloon injury compared with the uninjured controls. CSE activity was also correspondingly reduced. Endogenous production of H(2)S in the injured carotid artery was significantly inhibited at 1 week and 4 weeks after balloon injury. Treatment with NaHS (a donor of H(2)S) enhanced methacholine-induced vasorelaxation of balloon-injured artery. More importantly, treatment with NaHS significantly inhibited neointima formation (0.15 +/- 0.01 mm(2) versus 0.21 +/- 0.01 mm(2), P < 0.001) of the balloon-injured carotid arteries and reduced the intima/media ratio (1.05 +/- 0.07 versus 1.43 +/- 0.06, P < 0.001). A significant decrease in vascular smooth muscle cell proliferation was demonstrated by bromodeoxyuridine incorporation at day 7 after injury. In conclusion, CSE expression and H(2)S production are reduced during the development of balloon injury-induced neointimal hyperplasia, and treatment with NaHS significantly reduces neointimal lesion formation.

Methylglyoxal (MG), a highly reactive molecule, has been implicated in the development of insulin resistance. We investigated whether fructose, a precursor of MG, induced ONOO(-) generation and whether this process was mediated via endogenously increased MG formation. Fructose significantly increased MG generation in vascular smooth muscle cells (VSMCs) in a concentration and time dependent manner. The intracellular production of MG was increased by 153+/-23% or 259+/-28% after cells were treated 6 h with fructose (15 mM or 30 mM), compared with production from untreated cells (p<0.01, n=4 for each group). A significant increase in the production of ONOO(-), NO, and O(2)(*-), was found in the cells treated with fructose (15 mM) or MG (10 microM). Fructose- or MG-induced ONOO(-) generation was significantly inhibited by MG scavengers, including reduced glutathione or N-acetyl-l-cysteine, and by O(2)(*-) or NO inhibitors, such as diphenylene iodonium, superoxide dismutase or N-nitro-l-arginine methyl ester. Moreover, an enhanced iNOS expression was also observed in the cells treated directly with MG which was significantly inhibited when co-application with N-acetyl-l-cysteine. Our results demonstrated that fructose is capable of inducing a significant increase in ONOO(-) production, which is mediated by an enhanced formation of endogenous MG in VSMCs.