Ischemia-reperfusion injury of the isolated diabetic rat heart: effect of the antioxidant stobadine.

The etiology of diabetic complications is strongly associated with increased oxidative stress. The aim of the present study was to evaluate the effect of the potent antioxidant stobadine (STB) on global ischemia-reperfusion cardiac injury in the rat model of diabetes mellitus (DM). Diabetes was induced by multiple low doses of streptozotocin.

Antioxidant SMe1EC2 may attenuate the disbalance of sodium homeostasis in the organism induced by higher intake of cholesterol.

The study was focused to the influence of higher intake of cholesterol on properties of the renal Na,K-ATPase, a key system in maintaining the homeostasis of sodium in the organism. Feeding for 4 weeks with cholesterol-enriched food for rats afflicted with hereditary hypertriglyceridemia by itself enhanced the activity of Na,K-ATPase, probably as a consequence of higher number of active enzyme molecules as suggested by 32 % increase of V (max) value. This may be hypothesized as a reason for the increased retention of sodium.

Toxicological aspects of the use of phenolic compounds in disease prevention.

The consumption of a diet low in fat and enhanced by fruits and vegetables, especially rich in phenolic compounds, may reduce risks of many civilization diseases. The use of traditional medicines, mainly derived from plant sources, has become an attractive segment in the management of many lifestyle diseases. Concerning the application of dietary supplements (based on phenolic compounds) in common practice, the ongoing debate over possible adverse effects of certain nutrients and dosage levels is of great importance.

Delineating diseases by IMS-MS profiling of serum N-linked glycans.

Altered branching and aberrant expression of N-linked glycans is known to be associated with disease states such as cancer. However, the complexity of determining such variations hinders the development of specific glycomic approaches for assessing disease states. Here, we examine a combination of ion mobility spectrometry (IMS) and mass spectrometry (MS) measurements, with principal component analysis (PCA) for characterizing serum N-linked glycans from 81 individuals: 28 with cirrhosis of the liver, 25 with liver cancer, and 28 apparently healthy.

Protection of the vascular endothelium in experimental situations.

One of the factors proposed as mediators of vascular dysfunction observed in diabetes is the increased generation of reactive oxygen species (ROS). This provides support for the use of antioxidants as early and appropriate pharmacological intervention in the development of late diabetic complications. In streptozotocin (STZ)-induced diabetes in rats we observed endothelial dysfuction manifested by reduced endothelium-dependent response to acetylcholine of the superior mesenteric artery (SMA) and aorta, as well as by increased endothelaemia.

Different experimental approaches in modelling cataractogenesis: An overview of selenite-induced nuclear cataract in rats.

Cataract, the opacification of eye lens, is the leading cause of blindness worldwide. At present, the only remedy is surgical removal of the cataractous lens and substitution with a lens made of synthetic polymers. However, besides significant costs of operation and possible complications, an artificial lens just does not have the overall optical qualities of a normal one.

Neuropathy in a rat model of mild diabetes induced by multiple low doses of streptozotocin: effects of the antioxidant stobadine in comparison with a high-dose alpha-lipoic acid treatment.

Hyperglycaemia-induced oxidative stress makes an important contribution to the aetiology of diabetic neuropathy. The aim of our study was to evaluate the effect of the antioxidant stobadine (STB) in comparison with a treatment by a high-dose of alpha-lipoic acid (ALA), on the neurological consequences of chronic hyperglycaemia in an animal model of diabetes in Wistar rats (16 weeks old), made diabetic by streptozotocin (STZ 3 x 20 mg i.v.

Pycnogenol improves left ventricular function in streptozotocin-induced diabetic cardiomyopathy in rats.

We studied whether Pycnogenol (PYC) may attenuate the development of experimental streptozotocin-induced diabetic cardiomyopathy in rat. In addition, we aimed to study whether PYC affects cardiac oxidative stress and the protein expression of reactive oxygen species (ROS)-producing molecules (gp91(phox)-containing NADPH oxidase and NO-signalling proteins). Experimental diabetes mellitus was manifested by hyperglycaemia and impaired cardiac function estimated using left ventricular catheterisation in vivo.

Identification of N-glycan serum markers associated with hepatocellular carcinoma from mass spectrometry data.

Glycocylation represents the most complex and widespread post-translational modifications in human proteins. The variation of glycosylation is closely related to oncogenic transformation. Therefore, profiling of glycans detached from proteins is a promising strategy to identify biomarkers for cancer detection.

Detection of hepatocellular carcinoma using glycomic analysis.

Purpose: Hepatocellular carcinoma (HCC) represents an increasing health problem in the United States. Serum alpha-fetoprotein, the currently used clinical marker, is elevated in only approximately 60% of HCC patients; therefore, the identification of additional markers is expected to have significant public health impact. The objective of our study was to quantitatively assess N-glycans originating from serum glycoproteins as alternative markers for the detection of HCC.

Integrated peptide and glycan biomarker discovery using MALDI-TOF mass spectrometry.

Quantitative comparison of peptides and glycans in serum is conducted using matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) to identify biomarkers. A peak selection algorithm is developed to identify a panel of integrated peptide and glycan peaks to distinguish hepatocellular carcinoma (HCC) cases from high-risk population of patients with chronic liver disease (CLD). Candidate peptide and glycan markers selected frequently in multiple runs of the algorithm are presented.

Breast cancer diagnosis and prognosis through quantitative measurements of serum glycan profiles.

Background: Glycosylated proteins play important roles in cell-to-cell interactions, immunosurveillance, and a variety of receptor-mediated and specific protein functions through a highly complex repertoire of glycan structures. Aberrant glycosylation has been implicated in cancer for many years.

Methods: We performed specific MALDI mass spectrometry (MS)-based glycomic profile analyses of permethylated glycans in sera from breast cancer patients (12, stage I; 11, stage II; 9, stage III; and 50, stage IV) along with sera from 27 disease-free women.

Analysis of MALDI-TOF mass spectrometry data for detection of glycan biomarkers.

We present a computational framework for analysis of MALDI-TOF mass spectrometry data to enable quantitative comparison of glycans in serum. The proposed framework enables a systematic selection of glycan structures that have good generalization capability in distinguishing subjects from two pre-labeled groups. We applied the proposed method for a biomarker discovery study that involves 203 participants from Cairo, Egypt; 73 hepatocellular carcinoma (HCC) cases, 52 patients with chronic liver disease (CLD), and 78 healthy individuals.

Analysis of MALDI-TOF mass spectrometry data for discovery of peptide and glycan biomarkers of hepatocellular carcinoma.

This paper presents computational methods to analyze MALDI-TOF mass spectrometry data for quantitative comparison of peptides and glycans in serum. The methods are applied to identify candidate biomarkers in serum samples of 203 participants from Egypt; 73 hepatocellular carcinoma (HCC) cases, 52 patients with chronic liver disease (CLD) consisting of cirrhosis and fibrosis cases, and 78 population controls. Two complementary sample preparation methods were applied prior to generating mass spectra: (1) low molecular weight (LMW) enrichment of each serum sample was carried out for MALDI-TOF quantification of peptides, and (2) glycans were enzymatically released from proteins in each serum sample and permethylated for MALDI-TOF quantification of glycans.

Comparative glycomic mapping through quantitative permethylation and stable-isotope labeling.

Comparative glycan quantification has thus far been a challenging task due to the lack of sensitive and reproducible analytical techniques. We introduce here a combination of quantitative permethylation and isotope labeling of glycans as an approach (C-GlycoMAP) allowing precise comparison between different samples in a single MALDI-MS analysis. Samples are either methylated or deuteriomethylated prior to their mixing and mass spectrometric acquisitions.

Alterations in the serum glycome due to metastatic prostate cancer.

Glycomic profiles derived from human blood sera of 10 healthy males were compared to those from 24 prostate cancer patients. The profiles were acquired using MALDI-MS of permethylated N-glycans released from 10-microL sample aliquots. Quantitative permethylation was attained using solid-phase permethylation.

Effect of acetylcholine and ischaemia/reperfusion injury on the heart of rats with STZ-induced experimental diabetes.

Objectives: To investigate the effect of acetylcholine (ACh) and ischaemia/reperfusion injury on functional changes and dysrhythmias of the isolated diabetic rat heart.

Methods And Results: On retrogradely perfused hearts isolated from 10-week-old diabetic rats (streptozotocin 30 mg/kg b.w.

Electrophoretic analysis of oxidatively modified eye lens proteins in vitro: implications for diabetic cataract.

Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) profiles of eye lens proteins showed that both progression of diabetic cataract in rats in vivo and precipitation of soluble eye lens proteins stressed by free radicals in vitro were accompanied by significant protein cross-linking. There was a noticeable contribution of disulfide bridges to protein cross-linking in diabetic eye lens in vivo. In contrast, under conditions in vitro, when eye lens proteins were exposed to hydroxyl or peroxyl radicals, we showed that the participation of reducible disulfide linkages in the formation of high molecular mass products was markedly lower.

Effect of the pyridoindole antioxidant stobadine on development of experimental diabetic cataract and on lens protein oxidation in rats: comparison with vitamin E and BHT.

Purpose: The aim of this study was to investigate the effect of dietary supplementation with the pyridoindole antioxidant stobadine on the development of diabetic cataract in rats. The findings were compared with the effect of the natural antioxidant vitamin E and the well known phenolic synthetic antioxidant butylated hydroxytoluene.

Methods: Streptozotocin induced diabetic male Wistars rats were fed for 18 weeks a standard diet or a diet supplemented with stobadine (0.