Concentrations Of End Products Research Articles

Abstract 656: N-acetylcystein Reduces Lipid Peroxidation and Advanced Glycation Related to Prevention of Macrophage Endoplasmic Reticulum Stress Induced by Albumin Isolated from Rats With Chronic Kidney Disease

Objective: We analyzed the influence of N-acetylcysteine (NAC) in chronic kidney disease (CKD) rats on the plasma concentration of lipid peroxides (TBARS) and advanced glycation end products (AGE) and on the impact of serum CKD-albumin in the development of macrophage endoplasmic reticulum stress (ERS). Methods: CKD was induced by 5/6 nephrectomy in 2-month old male Wistar rats. Controls (C) were sham operated. Animals were treated or not with NAC (600mg/L of water). FPLC isolated serum albumin was purified by alchoolic extraction. J774 macrophages were incubated with serum albumin (1mg/mL; 18h) from all groups, and the expression of ERS markers (protein disulfide isomerase - PDI and Grp94 chaperone) determined by immunoblot. Comparisons were done by one-way ANOVA, Student t test. Results: After 60 days of CKD, body weight was 10% lower in CKD compared to C (p<0.01). This was prevented by NAC. Urea, creatinine, total cholesterol (TC), triglycerides (TG) (mg/dL), urinary protein excretion (mg/24h) (C, n= 31; C+NAC, n=20; CKD, n=74; CKD+NAC, n=32), total AGE and pentosidine (n= 8; fluorescence arbitrary unit) and TBARS (n= 7; nmoL/mL) were higher in CKD (122±8; 0.9±0.07; 151±6; 83±4; 46±2.5; 32620±673; 16700±1370; 6.6±0.5, respectively) and in CKD+NAC (91.4±5; 0.6±0.02; 126±7.5; 73±6; 51±3.5; 24,720±1,114; 10,080±748; 4.5±0.5, respectively) in comparison to C (41±0.9; 0.4±0.03; 76±2.7; 51.5±3; 14±0.9; 21,750±960; 5,314±129; 2±0.2, respectively; p<0.001) and C+NAC (40±0.9; 0.3±0.02; 76±2.6; 68±4; 18.4±1.5; 20,040±700; 5,050±267; 1.8±0.2, respectively; p<0,001). TC, urea, creatinine, total AGE, pentosidine and TBARS were respectively, 17%, 25%, 33%, 24%, 40% and 28% (p<0.01) lower in CKD+NAC, than in CKD. Glycemia was higher in C+NAC (107±4.6) and CKD+NAC (107±2.6) than in C (96±1.8; p<0.05) and CKD (98±1.6; p<0.01), respectively. In macrophages (n=6), CKD albumin increased PDI (5 and 7 times, p<0.01) and Grp94 (66% and 80%, p<0.01) in comparison to C and CKD+NAC-albumin treated cells, respectively. Conclusion: NAC reduces plasma lipid peroxidation and AGE and abrogates ERS induced by CKD-albumin. This may contribute to attenuate the deleterious effects of CKD-albumin on lipid accumulation in macrophages helping preventing atherogenesis in CKD.

Cellulase inhibition by high concentrations of monosaccharides.

Biological degradation of biomass on an industrial scale culminates in high concentrations of end products. It is known that the accumulation of glucose and cellobiose, end products of hydrolysis, inhibit cellulases and decrease glucose yields. Aside from these end products, however, other monosaccharides such as mannose and galactose (stereoisomers of glucose) decrease glucose yields as well. NMR relaxometry measurements showed direct correlations between the initial T2 of the liquid phase in which hydrolysis takes place and the total glucose production during cellulose hydrolysis, indicating that low free water availability contributes to cellulase inhibition. Of the hydrolytic enzymes involved, those acting on the cellulose substrate, that is, exo- and endoglucanases, were the most inhibited. The β-glucosidases were shown to be less sensitive to high monosaccharide concentrations except glucose. Protein adsorption studies showed that this inhibition effect was most likely due to catalytic, and not binding, inhibition of the cellulases.

Ramipril protects the endothelium from high glucose-induced dysfunction through CaMKKβ/AMPK and heme oxygenase-1 activation.

This study aims to investigate the effects of ramipril (RPL) on endothelial dysfunction associated with diabetes mellitus using cultured human aortic endothelial cells (HAECs) and a type 2 diabetic animal model. The effect of RPL on vasodilatory function in fat-fed, streptozotocin-treated rats was assessed. RPL treatment of 8 weeks alleviated insulin resistance and inhibited the decrease in endothelium-dependent vasodilation in diabetic rats. RPL treatment also reduced serum advanced glycation end products (AGE) concentration and rat aorta reactive oxygen species formation and increased aorta endothelium heme oxygenase-1 (HO-1) expression. Exposure of HAECs to high concentrations of glucose induced prolonged oxidative stress, apoptosis, and accumulation of AGEs. These effects were abolished by incubation of ramiprilat (RPT), the active metabolite of RPL. However, treatment of HAECs with STO-609, a CaMKKβ (Ca(2+)/calmodulin-dependent protein kinase kinase-β) inhibitor; compound C, an AMPK (AMP-activated protein kinase) inhibitor; and Zn(II)PPIX, a selective HO-1 inhibitor, blocked these beneficial effects of RPT. In addition, RPT increased nuclear factor erythroid 2-related factor-2 (Nrf-2) nuclear translocation and activation in a CaMKKβ/AMPK pathway-dependent manner, leading to increased expression of the Nrf-2-regulated antioxidant enzyme, HO-1. The inhibition of CaMKKβ or AMPK by pharmaceutical approach ablated RPT-induced HO-1 expression. Taken together, RPL ameliorates insulin resistance and endothelial dysfunction in diabetes via reducing oxidative stress. These effects are mediated by RPL activation of CaMKK-β, which in turn activates the AMPK-Nrf-2-HO-1 pathway for enhanced endothelial function.

Ramipril protects the endothelium from hyperglycaemia‐induced dysfunction through AMPK and HO‐1 activation (851.10)

Aims: To investigate the effects of ramipril (RPL), an angiotensin‐converting enzyme (ACE) inhibitor, on endothelial dysfunction associated with diabetes mellitus using cultured human aortic endothelial cells (HAECs) and a type 2 diabetic animal model.Methods and results: The effect of RPL on vasodilatory function in fat‐fed, streptozotocin‐treated rats was assessed. RPL treatment for 16 weeks starting at 8 weeks attenuated the decrease in endothelium‐dependent vasodilation in diabetic rats. RPL treatment also reduced serum advanced glycation end products (AGEs) concentration. Exposure of HAECs to high concentrations of glucose induced prolonged oxidative stress, apoptosis and accumulation of AGEs in HAEC. These effects were abolished by RPL incubation. In addition, RPL increased nuclear factor erythroid 2‐related factor‐2 (Nrf‐2) activation in a CaMKKβ/AMPK pathway dependent manner. RPL treatment increased the expression of the Nrf‐2‐regulated antioxidant enzyme, heme oxygenase‐1 (HO‐1).Conclusion: Ramipril ameliorates endothelial dysfunction in diabetes by enhancing vasodilation in addition to reducing oxidative stress. These effects are mediated by ramipril activation of CaMKK‐β, which in turn activates the AMPK‐Nrf‐2‐HO‐1 pathway for enhanced endothelial function.Grant Funding Source: Supported by Shanghai Key Laboratory of Human Performance(SUS) 11DZ2261100

Inhibitory effects of substrate and soluble end products on biohydrogen production of the alkalithermophile Caloramator celer: Kinetic, metabolic and transcription analyses

Abstract In this study the tolerance of the alkalithermophile Caloramator celer towards substrate (glucose) and soluble end product (acetate, formate and ethanol) inhibition was assessed employing nonlinear inhibition models. In addition, the effects of subinhibitory concentrations of end products on fermentative metabolism and regulation of 12 key genes involved in pyruvate catabolism were studied. Optimal growth and H2 production were found at 50 mM of glucose and the critical substrate concentration was observed at 290–360 mM. Two inhibition models revealed that ethanol had a higher inhibitory effect on growth rate, whereas H2 production kinetics was more sensitive towards increasing concentrations of acetate and formate. Acetate, the main soluble metabolite of the fermentation, inhibited the H2 production by increasing the ionic strength in the medium. Subinhibitory concentrations of soluble end products induced changes in the metabolite profile of C. celer, specifically exogenous acetate (80 mM) and ethanol (40 mM) slightly increased the H2 yield by 4 and 7%, respectively. However, despite the observed metabolic shifts, gene regulation was minimal and not always in agreement with the measured product yields. Overall, the results suggest that further optimization of the H2 production process from C. celer should focus on methods to evolve adapted osmotolerant strains and/or remove soluble metabolites, especially acetate, from the culture.

Maternal Dietary Docosahexaenoic Acid Supplementation Attenuates Fetal Growth Restriction and Enhances Pulmonary Function in a Newborn Mouse Model of Perinatal Inflammation1–3

The preterm infant is often exposed to maternal and neonatal inflammatory stimuli and is born with immature lungs, resulting in a need for oxygen therapy. Nutritional intervention with docosahexaenoic acid (DHA; 6.3 g/kg of diet) has been shown to attenuate inflammation in various human diseases. Previous studies demonstrated that maternal DHA supplementation during late gestation and lactation attenuated hyperoxic lung injury in newborn mouse pups. In the present studies, we tested the hypothesis that DHA supplementation to the dam would reduce hyperoxic lung injury and growth deficits in a more severe model of systemic maternal inflammation, including lipopolysaccharide (LPS) and neonatal hyperoxia exposure. On embryonic day 16, dams were placed on DHA (6.3 g DHA/kg diet) or control diets and injected with saline or LPS. Diets were maintained through weaning. At birth, pups were placed in room air or hyperoxia for 14 d. Improvements in birth weight (P < 0.01), alveolarization (P ≤ 0.01), and pulmonary function (P ≤ 0.03) at 2 and 8 wk of age were observed in pups exposed to perinatal inflammation and born to DHA-supplemented dams compared with control diet-exposed pups. These improvements were associated with decreases in tissue macrophage numbers (P < 0.01), monocyte chemoattractant protein-1 expression (P ≤ 0.05), and decreases in soluble receptor for advanced glycation end products concentrations (P < 0.01) at 2 and 8 wk. Furthermore, DHA supplementation attenuated pulmonary fibrosis, which was associated with the reduction of matrix metalloproteinases 2, 3, and 8 (P ≤ 0.03) and collagen mRNA (P ≤ 0.05), and decreased collagen (P < 0.01) and vimentin (P ≤ 0.03) protein concentrations. In a model of severe inflammation, maternal DHA supplementation lessened inflammation and improved lung growth in the offspring. Maternal supplementation with DHA may be a therapeutic strategy to reduce neonatal inflammation.

Vitamin D manipulates miR-181c, miR-20b and miR-15a in human umbilical vein endothelial cells exposed to a diabetic-like environment

BackgroundHigh blood and tissue concentrations of glucose and advanced glycation end-products are believed to play an important role in the development of vascular complications in patients with diabetes mellitus (DM) and chronic kidney disease. MicroRNAs (miRNA) are non-coding RNAs that regulate gene expression in a sequence specific manner. MiRNA are involved in various biological processes and become novel biomarkers, modulators and therapeutic targets for diseases such as cancer, atherosclerosis, and DM. Calcitriol (the active form of vitamin D) may inhibit endothelial proliferation, blunt angiogenesis, and be a cardioprotective agent. Calcitriol deficiency is a risk factor for DM and hypertension. The aim of this project was to study the miRNA microarray expression changes in human umbilical vein endothelial cells (HUVEC) treated in a diabetic-like environment with the addition of calcitriol.MethodsHUVEC were treated for 24 h with 200 μg/ml human serum albumin (HSA) and 100 mg/dl glucose (control group) or 200 μg/ml AGE-HSA, and 250 mg/dl glucose (diabetic-like environment), and physiological concentrations (10-10 mol/l) of calcitriol. miRNA microarray analysis and real time PCR to validate the miRNA expression profile and mRNA target gene expression were carried out.ResultsCompared to control, 31 mature human miRNA were differentially expressed in the presence of a diabetic-like environment. Addition of physiological concentrations of calcitriol revealed 39 differentially expressed mature human miRNA. MiR-181c, miR-15a, miR-20b, miR-411, miR-659, miR-126 and miR-510 were selected for further analysis because they are known to be modified in DM and in other biological disorders. The predicted targets of these miRNA (such as KLF6, KLF9, KLF10, TXNIP and IL8) correspond to molecular and biological processes such as immune and defense responses, signal transduction and regulation of RNA.ConclusionThis study identified novel miRNA in the field of diabetic vasculopathy and might provide new information about the effect of vitamin D on gene regulation induced by a diabetic-like environment. New gene targets that are part of the molecular mechanism and the therapeutic treatment in diabetic vasculopathy are highlighted.

Screening of plants from diversified natural grasslands for their potential to combine high digestibility, and low methane and ammonia production

A total of 156 plant species from 35 botanical families collected from diversified grasslands in the French Massif Central were screened in vitro for their potential to combine high nutritive value for ruminants and a reduced impact on the environment. The vegetative part of plants were analyzed for their chemical composition and incubated in a batch system containing buffered rumen fluid at 39°C for 24 h. The gas production and composition were recorded, and the fermentation end-product concentrations in the incubation medium and the in vitro true organic matter digestibility (IVTOMD) were determined. The results were expressed relative to perennial ryegrass (PRG) values used as a reference. We observed that no relationship between methane (CH4) and volatile fatty acids (VFA) was evidenced for 12 plants, the fermentation of these plants producing significantly less CH4 for a similar level of VFA production. In all, 13 plants showed 50% less CH4 production per unit of organic matter truly digested (OMTD) than PRG. Among these plants, two reduced CH4 by more than 80% and four species had an IVTOMD higher than 80%. The underlying modes of action seem to be different among plants: some result in an accumulation of H2 in the fermentation gas, but others do not. In terms of nitrogen (N) use efficiency, the fermentation of 37 plants halved the ratio between ammonia (N-NH3) and plant N content compared with PRG, of which six showed a complete absence of N-NH3 in the medium. Among these plants, four maintained the IVTDMO at values not significantly different from PRG (P>0.05). Considering the multi-criteria selection, 16 plants showed simultaneously a reduction of more than 80% in N-NH3 production and 30% in CH4 emission per unit of OMTD compared with PRG, including three with an IVTOMD higher than 80%. Overall, the botanical families that reduced simultaneously CH4 and N-NH3 most efficiently were the Rosaceae, Onagraceae, Polygonaceae and Dipsacaceae. The Onagraceae also gave high values for IVTOMD.

Remediation of Dichloromethane (CH2Cl2) Using Non-thermal, Atmospheric Pressure Plasma Generated in a Packed-Bed Reactor

This work describes the application of a non-thermal plasma generated in a dielectric barrier packed-bed plasma reactor for the remediation of dichloromethane (CH2Cl2, DCM). The overall aim of this investigation is to identify the role of key process parameters and chemical mechanisms on the removal efficiency of DCM in plasma. The influence of process parameters, such as oxygen concentration, concentration of initial volatile organic compounds (VOCs), energy density, plasma residence time, and background gas, on the removal efficiency of 500 ppm DCM was investigated. Results showed a maximum removal efficiency with the addition of 2-4% oxygen into a nitrogen plasma. It is thought that oxygen concentrations in excess of 4% decreased the decomposition of chlorinated VOCs as a result of ozone and nitrogen oxide formation. Increasing the residence time and the energy density resulted in increasing the removal efficiency of chlorinated VOCs in plasma. A chemical kinetic model has been developed on the basis of the proposed reaction scheme, and the calculation of end product concentrations are in general good agreement with the observed values. With the understanding of the effect of the key parameters, it has been possible to optimize the remediation process.

Изучение роли факторов роста фибробластов (β-FGF, TGFβ1), маркеров воспаления (IL-6, TNF-α, СRP) и конечных продуктов гликирования (AGE, RAGE) у пациентов с ишемической болезнью сердца и сахарным диабетом 2 типа

Aims. To evaluate plasma levels of transforming growth factor beta (TGFbeta1), basic fibroblast growth factor (bFGF), markers for nonspecific inflammatory process (interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-alpha), C-reactive protein (CRP)) and their putative correlation with advanced glycation end-products relative to diabetes compensation in patients with ischemic heart disease (IHD). Materials and Methods. 87 patients with IHD were enrolled in this study. All subjects underwent standard clinical examination, including laboratory assessment of glycemic parameters, lipid panel and renal function, with echocardiography, supplemented with coronary angiography. Analyses for study parameters were performed on samples obtained from aorta and, separately, from cubital vein during coronary angiography. Results. Diabetes mellitus in patients with IHD is firmly associated with TGFbeta1, IL-6 and CRP elevation in both arterial and venous plasma. TGFbeta1 positively correlates with lipid profile parameters. Plasma concentration of inflammatory markers and advanced glycation end-products positively correlates with the extent of coronary lesions in relation to the presence of diabetes mellitus. Conclusion. Our data suggests the interplay between connective tissue growth factors and lipid metabolism in the atherosclerotic process.

Neurite regeneration in adult rat retinas exposed to advanced glycation end-products and regenerative effects of neurotrophin-4

The purpose of this study was to determine the effect of low concentrations of advanced glycation end-products on neurite regeneration in isolated rat retinas, and to determine the effects of neurotrophin-4 on regeneration in advanced glycation end-products exposed retinas. Retinal explants of 4 adult Sprague-Dawley rats were cultured on collagen gel and were incubated in; (1) serum-free control culture media, (2) glucose-advanced glycation end-products-bovine serum albumin media, (3) glycolaldehyde-advanced glycation end-products-bovine serum albumin media, (4) glyceraldehyde-advanced glycation end-products-bovine serum albumin media, (5) glucose-advanced glycation end-products+neurotrophin-4 media, (6) glycolaldehyde-advanced glycation end-products+neurotrophin-4 media, or (7) glyceraldehyde-advanced glycation end-products+neurotrophin-4 supplemented culture media. After 7 days, the number of regenerating neurites from the explants was counted. Then, explants were fixed, cryosectioned, and stained for TUNEL. The ratio of TUNEL-positive cells to all cells in the ganglion cell layer was determined. Immunohistochemical examinations for the active-form of caspase-9 and apoptosis-inducing factor were performed. In retinas incubated with advanced glycation end-products containing media, the number of regenerating neurites were fewer than in retinas without advanced glycation end-products, and the number of TUNEL-positive cells and caspase-9- and apoptosis-inducing factor-immunopositive cells was significantly higher than in control media. Neurotrophin-4 supplementation increased the numbers of regenerating neuritis, and the number of TUNEL-positives, caspase-9-, and apoptosis-inducing factor-immunopositive cells were significantly fewer than that in advanced glycation end-products without neurotrophin-4 media. Low doses of advanced glycation end-products impede neurite regeneration in the rat retinas. Neurotrophin-4 significantly enhances neurite regeneration in retinas exposed to advanced glycation end-products.

ANTIATHEROGENIC AND PLEIOTROPIC ACTIVITY OF VARIOUS DOSES OF ATORVASTATIN IN PATIENTS WITH ISCHEMIC STROKE

Aim. To study the effects of various atorvastatin doses on blood lipids, hemostatic parameters, endothelial function, renin-angiotensin￾aldosterone (RAAS) system, and circadian profile of blood pressure (BP) in patients with ischemic stroke (IS). Material and methods. The study included 34 IS patients (mean age 58,0±6,6 years) with serum levels of low-density lipoprotein cholesterol (LDL-CH) &gt;2,5 mmol/l, arterial hypertension (AH), and BP levels &lt;160/100 mm Hg. All participants were randomised into Groups I and II, which received atorvastatin in daily doses of 10 and 40 mg, respectively, for 12 weeks. The atorvastatin effects on lipid profile, hemostatic parameters, nitric oxide (NO) end products, endothelin-1 (ET-1), angiotensin (AT) II, blood serotonin, and BP dynamics were assessed. Results. After 12 weeks, the patients receiving 10 and 40 mg/d of atorvastatin demonstrated a significant reduction in total CH (by 26,6% (p&lt;0,001) and 33% (p&lt;0,001), respectively), LDL-CH (by 32% (p&lt;0,001) and 44% (p&lt;0,001), respectively), and triglycerides (TG) (by 14% (p&lt;0,001) and 24% (p&lt;0,001), respectively). In both groups, there was no marked dynamics in the initially elevated levels of fibrinogen. In Group I, spontaneous platelet aggregation (PA) reduced by 22,6% (p&lt;0,05). Moreover, in Group I, ADP-induced PA decreased by 16,7% (p&lt;0,05) and 67,2% (p&lt;0,01) for 0,5 and 2 μM of ADP, respectively. In Group II, the respective figures were 30,1% (p&lt;0,05) and 31,6% (p&lt;0,01). The concentration of NO end products increased in both Group I (+15% (p&lt;0,05) after 12 weeks) and Group II (+7,7% (p&lt;0,05) after 6 weeks; +15,5% (p&lt;0,01) after 12 weeks). In all participants (Groups I and II; n=34), atorvastatin therapy was associated with a reduction in ET-1 levels by 4,8% (p&lt;0,05). In Group II, there was a significant reduction in the levels of AT II (-7,1%; p&lt;0,05; n=17) and serotonin (-28,6%; p&lt;0,05; n=11). These changes were accompanied by reduced BP variability, time BP index, and area BP index. Conclusion. In IS patients with hyperlipidemia and AH, atorvastatin demonstrated a dose-dependent lipid-lowering effect on LDL-CH and TG, as well as a dose-dependent pleiotropic activity.

Cytotoxic role of advanced glycation end-products in PC12 cells treated with β-amyloid peptide

Alzheimer's disease (AD) is the most common type of dementia afflicting the elderly. Recent studies have increasingly suggested that a high concentration of advanced glycation end products (AGEs) may be important in AD pathogenesis. However, the mechanisms and pathways involved remain unknown. The aim of this study was to explore whether the mechanism of the effect of AGEs on Aβ‑PC12 cells [PC12 cells treated with β‑amyloid (Aβ) peptide] was associated with oxidative stress; and to study whether inhibiting the activity of the receptor for AGE (RAGE) attenuated the toxic effect of AGEs and Aβ on PC12 cells. Several PC12 cells were pretreated with Aβ, and were then treated with different concentrations of AGEs. Other PC12 cells were treated with trypsin, a pancreatic protein enzyme and an inhibitor of RAGE, and were then treated with Aβ and AGEs. Apoptosis was measured by flow cytometry (FCM) and cell viability was measured by MTT assay. RAGE and nuclear factor‑κB (NF‑κB) were measured by reverse transcription-polymerase chain reaction (RT‑PCR) assay. With an increase in AGE concentration, the viability of Aβ‑PC12 cells treated with AGEs decreased. However, the Aβ‑PC12 cell viability was greater in the trypsin group than in the non‑trypsin group. Cell apoptosis rates and mRNA expression of RAGE and NF‑κB in Aβ‑PC12 cells treated with AGEs were significantly higher than in the Aβ‑PC12 cells. AGEs and Aβ were neurotoxic, and RAGE triggered the neural cytotoxic role of AGEs in Aβ‑PC12 cells. The molecular mechanisms may be connected with the expression of NF‑κB and apoptosis mediated by RAGE. Inhibiting the activity of RAGE may mitigate the toxic effect of AGEs and Aβ on neural cells.

Effects of different doses of rosuvastatin on blood lipids and lipoproteins, endothelial function, and cerebral blood flow in patients with hyperlipidemia and cerebral ischemic stroke-complicated hypertension

Objective: to study the dose-dependent effect of rosuvastatin on blood lipids and lipoproteins (LP), endothelial functional activity, coagulation, and safety parameters in patients with hyperlipidemia (HLP) and hypertension after cerebral ischemic stroke (CIS). Subjects and method. The trial included 34 patients (mean age 59,4±7,4 years) with types IIa or IIb HLP and CIS-complicated hypertension. The patients were randomized to 2 groups: 1) rosuvastatin 10 mg and 2) rosuvastatin 20 mg. The trial lasted 12 weeks. The dose of rosuvastatin remained unchanged throughout the trial. The authors evaluated the impact of therapy on the blood concentration of lipids, LP, fibrinogen, end products of nitric oxide (NO) metabolism, and endothelin-1 (ET-1), cerebral blood flow by great cerebral artery Doppler ultrasound data, as well as the parameters reflecting the safety of the therapy. Results. After 12-week therapy with rosuvastatin 10 and 20 mg, there was a significant decrease in the level of cholesterol by 30 and 35%, low-density lipoprotein (LDL) cholesterol by 40 and 45%, and triglycerides by 18 and 26%, respectively. Increasing the dose of rosuvastatin was attended by a significant rise (by 18%) in the number of patients with target LDL cholesterol levels. Rosuvastatin therapy caused no changes in the high baseline level of fibrinogen. At the same time, at the rosuvastatin doses of 10 and 20 mg, the concentrations of end products of NO metabolism increased by 14,3 and 12,4%, respectively. The vasoprotective effect of rosuvastatin 20 mg showed itself just at therapy week 6. Significantly decreased ET-1 levels were found when rosuvastatin was given in a dose of 10 mg; this was directly related to the baseline concentration of ET-1. In the patients who had an ET-1 level of &gt;0,51 fmol/ml, its drop was 22,5% (p

Constraint-based genome-scale metabolic modeling of Clostridium acetobutylicum behavior in an immobilized column

In this study a step-wise optimization procedure was developed to predict solvent production using continuous ABE fermentation with immobilized cells. The modeling approach presented here utilizes previously published constraint-based metabolic model for Clostridium acetobutylicum without direct flux constraints. A recently developed flux ratio constraint method was adopted for the model. An experimental data set consisting of 25 experiments using different sugar mixtures as substrates and differing dilution rates was simulated successfully with the modeling approach. Converted to end product concentrations the mean absolute error for acetone was 0.31 g/l, for butanol 0.49 g/l, and for ethanol 0.17 g/l. The modeling approach was validated with another data set from similar experimental setup. The model errors for the validation data set was 0.24 g/l, 0.60 g/l, and 0.17 g/l for acetone, butanol, and ethanol, respectively.

Injury of cortical neurons is caused by the advanced glycation end products-mediated pathway.

Advanced glycation end products lead to cell apoptosis, and cause cell death by increasing endoplasmic reticulum stress. Advanced glycation end products alone may also directly cause damage to tissues and cells, but the precise mechanism remains unknown. This study used primary cultures of rat cerebral cortex neurons, and treated cells with different concentrations of glycation end products (50, 100, 200, 400 mg/L), and with an antibody for the receptor of advanced glycation end products before and after treatment with advanced glycation end products. The results showed that with increasing concentrations of glycation end products, free radical content increased in neurons, and the number of apoptotic cells increased in a dose-dependent manner. Before and after treatment of advanced glycation end products, the addition of the antibody against advanced glycation end-products markedly reduced hydroxyl free radicals, malondialdehyde levels, and inhibited cell apoptosis. This result indicated that the antibody for receptor of advanced glycation end-products in neurons from the rat cerebral cortex can reduce glycation end product-induced oxidative stress damage by suppressing glycation end product receptors. Overall, our study confirms that the advanced glycation end products-advanced glycation end products receptor pathway may be the main signaling pathway leading to neuronal damage.

Influence of dietary fiber type and amount on energy and nutrient digestibility, fecal characteristics, and fecal fermentative end-product concentrations in captive exotic felids fed a raw beef-based diet

Little nutritional or metabolic information has been collected from captive exotic cats fed raw diets. In particular, fiber types and concentrations for use in raw meat-based diets for captive exotic felids have not been well studied. Our objective was to evaluate the effects of fiber type and concentration on apparent total tract energy and macronutrient digestibility, fecal characteristics, and fecal fermentative end-products in captive exotic felids. Four animals of each captive exotic species (jaguar (Panthera onca), cheetah (Acinonyz jubatus), Malayan tiger (Panthera tigris corbetti), and Siberian tiger (Panthera tigris altaica) were randomized in four 4 × 4 Latin square designs (1 Latin square per species) to 1 of the 4 raw beef-based dietary treatments (94.7 to 96.7% beef trimmings): 2 or 4% cellulose or 2 or 4% beet pulp. Felid species, fiber type, and fiber concentration all impacted digestibility and fecal fermentative end-products. Inclusion of beet pulp increased (P ≤ 0.05) fecal short-chain fatty acids and fecal output in all cats. Inclusion of 2 and 4% cellulose, and 4% beet pulp increased (P ≤ 0.05) fecal bulk and diluted fecal branched-chain fatty acid concentrations compared with 2% beet pulp. Apparent total tract DM, OM, fat, and GE digestibility coefficients decreased (P ≤ 0.05) linearly with BW of cats. Additionally, fecal moisture, fecal score, and concentrations of fermentative end-products increased (P ≤ 0.05) with BW. Although the response of many outcomes was dependent on cat size, in general, beet pulp increased wet fecal weight, fecal scores, and fecal metabolites, and reduced fecal pH. Cellulose generally reduced DM and OM digestibility, but increased dry fecal weight and fecal percent DM. Although beet pulp and cellulose fibers were tested individually in this study, these data indicate that the optimum fiber type and concentration for inclusion in captive exotic felid diets is likely a combination of fermentable and nonfermentable fibers, with the optimal fiber blend being dependent on species. Smaller cats, such as cheetahs and jaguars, tolerated fermentable fibers, whereas larger cats, such as Malayan and Siberian tigers, appeared to require more insoluble fibers that limit fermentation and provide fecal bulk. Further research is required to test whether these trends hold true when fed in combination.

Membranar effects exerted in vitro by polyphenols – quercetin, epigallocatechin gallate and curcumin – on HUVEC and Jurkat cells, relevant for diabetes mellitus

Polyphenols are largely studied for their beneficial action in various pathologies, but the correlation with their effects on cell membranes is still elusive. In the present study we assessed the effects exerted in vitro by quercetin, epigallocatechin gallate and curcumin on membrane fluidity and transmembrane potential of human umbilical vein endothelial cells and Jurkat T lymphoblasts, in experimental conditions mimicking diabetes mellitus, i.e. high glucose conditions or increased concentration of advanced glycation end products. Results showed that the investigated polyphenols had beneficial effects on cell membranes altered in diabetic conditions, by restoring transmembrane potential and by membrane "stiffening". Moreover, they limited the release of pro-inflammatory factors, like monocyte chemotactic protein-1. These effects were more obvious for cells exposed to advanced glycation end products specific for the late stages of diabetes. Apparently, the inhibitory action of polyphenols on lipid peroxidation was associated with a decrease of membrane fluidity. Concluding, our in vitro study highlighted the potential beneficial action of polyphenols mainly in the late stages of diabetes, exerted at the level of membrane fluidity and transmembrane potential, accompanied by an anti-inflammatory effect on endothelial and immune cells.

Inhibition of arginase ameliorates experimental ulcerative colitis in mice

Nitric oxide (NO) is produced from the conversion of L-arginine by NO synthase (NOS) and regulates a variety of processes in the gastrointestinal tract. Considering the increased activity of arginase in colitis tissue, it is speculated that arginase could inhibit NO synthesis by competing for the same L-arginine substrate, resulting in the exacerbation of colitis. We examined the role of arginase and its relationship to NO metabolism in dextran sulfate sodium (DSS)-induced colitis. Experimental colitis was induced in mice by administration of 2.5% DSS in drinking water for 8 days. Treatment for arginase inhibition was done by once daily intraperitoneal injection of Nω-hydroxy-nor- arginine (nor-NOHA). On day 8, we evaluated clinical parameters (body weight, disease activity index, and colon length), histological features, the activity and expression of arginase, L-arginine content, the expression of NO synthase (NOS), and the concentration of NO end-product (NOx: nitrite + nitrate). Administration of nor-NOHA improved the worsened clinical parameters and histological features in DSS-induced colitis. Treatment with nor-NOHA attenuated the increased activity of arginase, upregulation of arginase Ι at both mRNA and protein levels, and decreased the content of L-arginine in colonic tissue in the DSS-treated mice. Conversely, despite the decreased expression of NOS2 mRNA, the decreased concentration of NOx in colonic tissues was restored to almost normal levels. The consumption of L-arginine by arginase could lead to decreased production of NO from NOS, contributing to the pathogenesis of the colonic inflammation; thus, arginase inhibition might be effective for improving colitis.

A new approach using biomarkers to elucidate the regression state of the invasive alga Caulerpa taxifolia in waters around the Balearic Islands (Western Mediterranean Sea)

Invasive algae alter the structure and function of ecosystems. The green alga Caulerpa taxifolia is an invasive alga introduced in the Mediterranean Sea, whereas Caulerpa prolifera is a native species in Mediterranean waters. The aim of the current work was to determine the oxidative status of both Caulerpa species by means of biomarker measures as a possible indicator of the regression state of C. taxifolia in waters around the Balearic Islands (western Mediterranean Sea). The levels of markers of lipid peroxidation, glutathione concentration, activities of antioxidant enzymes and caulerpenyne production were measured in C. prolifera and C. taxifolia fronds. The concentration of the end product of lipid peroxidation, malondialdehyde, was significantly higher in C. taxifolia than in C. prolifera samples. Antioxidant enzyme activities, namely superoxide dismutase glutathione peroxidase and glutathione reductase, as well as the reduced glutathione : glutathione disulfide ratio were lower in C. taxifolia than in C. prolifera, although the concentrations of malondialdehyde were higher in the alien species. No differences were found in catalase activity or in the concentration of caulerpenyne. In conclusion, the invasive alga C. taxifolia presented a more oxidised status, which could be related to its regression in Mallorcan coastal waters.