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In 1981, an unknown disease appeared in Spain, the Spanish Toxic Oil Syndrome. Nowadays and despite all efforts, the etiological agent is still unknown. Early studies showed a link between this illness and the consumption of denatured rapeseed oil fraudulently processed and marketed as edible oil. Two families of aniline derivatives present in these oils (fatty acid anilides and acylated phenyl amino propanediol derivatives or PAPs) were found to be good chemical markers of toxic oils. In this work, a new method has been developed to analyze these aniline derivatives in oil samples by HPLC-MS and. HPLC-MS/MS with an API source. For their quantification, three different internal standards were used, one for anilides and two for PAPs. Quantification limits were 8 ppm for anilides and 0.2 ppm for PAPs. Anilides and PAPs were found in marker-positive samples at levels up to 50 000 and 330 ppm, respectively. The relative abundance of the different fatty acid anilides and PAPs correlates with the fatty acid composition of the oils. More than 2600 different samples were analyzed by this method in the most exhaustive screening of suspected toxic oils carried out to date.

In CKD, uremic solutes may induce endothelial dysfunction, inflammation, and oxidative stress, leading to increased cardiovascular risk. We investigated whether the uremic solute indole-3 acetic acid (IAA) predicts clinical outcomes in patients with CKD and has prooxidant and proinflammatory effects. We studied 120 patients with CKD. During the median study period of 966 days, 29 patients died and 35 experienced a major cardiovascular event. Kaplan-Meier analysis revealed that mortality and cardiovascular events were significantly higher in the higher IAA group (IAA>3.73 µM) than in the lower IAA group (IAA<3.73 µM). Multivariate Cox regression analysis demonstrated that serum IAA was a significant predictor of mortality and cardiovascular events after adjustments for age and sex; cholesterol, systolic BP, and smoking; C-reactive protein, phosphate, body mass index, and albumin; diastolic BP and history of cardiovascular disease; and uremic toxins p-cresyl sulfate and indoxyl sulfate. Notably, IAA level remained predictive of mortality when adjusted for CKD stage. IAA levels were positively correlated with markers of inflammation and oxidative stress: C-reactive protein and malondialdehyde, respectively. In cultured human endothelial cells, IAA activated an inflammatory nongenomic aryl hydrocarbon receptor (AhR)/p38MAPK/NF-κB pathway that induced the proinflammatory enzyme cyclooxygenase-2. Additionally, IAA increased production of endothelial reactive oxygen species. In conclusion, serum IAA may be an independent predictor of mortality and cardiovascular events in patients with CKD. In vitro, IAA induces endothelial inflammation and oxidative stress and activates an inflammatory AhR/p38MAPK/NF-κB pathway., (Copyright © 2015 by the American Society of Nephrology.)

In chronic kidney disease (CKD), uremic solutes accumulate in blood and tissues. These compounds probably contribute to the marked increase in cardiovascular risk during the progression of CKD. The uremic solutes indoxyl sulfate and indole-3-acetic acid (IAA) are particularly deleterious for endothelial cells. Here we performed microarray and comparative PCR analyses to identify genes in endothelial cells targeted by these two uremic solutes. We found an increase in endothelial expression of tissue factor in response to indoxyl sulfate and IAA and upregulation of eight genes regulated by the transcription factor aryl hydrocarbon receptor (AHR). The suggestion by microarray analysis of an involvement of AHR in tissue factor production was confirmed by siRNA inhibition and the indirect AHR inhibitor geldanamycin. These observations were extended to peripheral blood mononuclear cells. Tissue factor expression and activity were also increased by AHR agonist dioxin. Finally, we measured circulating tissue factor concentration and activity in healthy control subjects and in patients with CKD (stages 3-5d), and found that each was elevated in patients with CKD. Circulating tissue factor levels were positively correlated with plasma indoxyl sulfate and IAA. Thus, indolic uremic solutes increase tissue factor production in endothelial and peripheral blood mononuclear cells by AHR activation, evoking a 'dioxin-like' effect. This newly described mechanism of uremic solute toxicity may help understand the high cardiovascular risk of CKD patients.

During chronic kidney disease (CKD), solutes called uremic solutes, accumulate in blood and tissues of patients. We developed an HPLC method for the simultaneous determination of several uremic solutes of clinical interest in biological fluids: phenol (Pol), indole-3-acetic acid (3-IAA), p-cresol (p-C), indoxyl sulfate (3-INDS) and p-cresol sulfate (p-CS). These solutes were separated by ion-pairing HPLC using an isocratic flow and quantified with a fluorescence detection. The mean serum concentrations of 3-IAA, 3-INDS and p-CS were 2.12, 1.03 and 13.03 μM respectively in healthy subjects, 3.21, 17.45 and 73.47 μM in non hemodialyzed stage 3-5 CKD patients and 5.9, 81.04 and 120.54 μM in hemodialyzed patients (stage 5D). We found no Pol and no p-C in any population. The limits of quantification for 3-IAA, 3-INDS, and p-CS were 0.83, 0.72, and 3.2 μM respectively. The within-day CVs were between 1.23 and 3.12% for 3-IAA, 0.98 and 2% for 3-INDS, and 1.25 and 3.01% for p-CS. The between-day CVs were between 1.78 and 5.48% for 3-IAA, 1.45 and 4.54% for 3-INDS, and 1.19 and 6.36% for p-CS. This HPLC method permits the simultaneous and quick quantification of several uremic solutes for daily analysis of large numbers of samples., (Copyright © 2011 Elsevier B.V. All rights reserved.)

p-Cresylsulfate, a metabolite of p-cresol, is reported as prototypic protein-bound uremic toxin, inefficiently removed by haemodialysis. The binding between p-cresylsulfate or p-cresol and human serum albumin was studied using microcalorimetry. The results confirm that the two molecules are protein-bound. However, the affinity of p-cresylsulfate and p-cresol toward human serum albumin is moderate at 25 degrees C and becomes relatively weak at physiological temperature, 37 degrees C. The binding principally involves van der Waals type interactions, and the binding sites of the two molecules are the same or very close. The low fraction of bound toxin (13-20%) appears to be insufficient to link strong binding to poor removal of this toxin by hemodialysis.

Fatty acid esters of 3-(N-phenylamino)-1,2-propanediol are currently considered the best chemical markers of toxic oils related to the Spanish toxic oil syndrome. Recent research in this area has undertaken the exhaustive and quantitative characterization of these compounds in oils collected during the epidemic outbreak. Current methods developed in this laboratory are based on solid phase extraction (SPE) using SCX cartridges followed by HPLC-APCI/MS/MS quantification. To circumvent the long and tedious extraction procedure, the SPE protocol was adapted for automatic extraction and the problems derived from the use of the immiscible solvents required for the SCX extraction were solved. Linearity of the analytical method was found in the same range as for the manual method. Extraction recoveries were 87 and 75% for 2-hydroxy-3-(N-phenylamino)propyl linoleate and 2-(linoleyloxy)-3-(N-phenylamino)propyl linoleate, respectively, and the corresponding coefficients of variation were approximately 1%, greatly improving reproducibility over manual procedures.

Toxic Oil Syndrome (TOS) was an epidemic disease related to the consumption of rapeseed oil denatured with aniline that made its sudden appearance in Spain in 1981. The fatty acid esters of 3-(N-phenylamino)-1,2-propanediol (PAP), which is a chemical class of by-products resulting from the reaction of aniline with oil components, have shown a strong association with TOS-related oils. These compounds also show some structural similarities to platelet-activating factor (PAF). In search of a toxic agent that could explain the widespread systemic effects observed in TOS patients, we investigated the intestinal absorption and biotransformation of the different PAP esters found in TOS-related oil samples and the possible pathophysiological effect of these mediators and their metabolic products if acting as PAF analogs. Results indicate that PAP esters are absorbed in the gastrointestinal tract and are distributed and stored in different organs, particularly in the liver and brown adipose tissue. PAP in these organs showed different patterns of fatty acids, indicating the ability of the gastrointestinal tract to modify the fatty acid composition of the parent PAP. Thus, the fatty acid profile of the PAP esters found in intestine appears to be related to the type of oil used as vehicle. Some of these PAP esters, when a long acyl chain was present in the sn-1 position of the molecule, showed an inhibitory effect on the PAF synthesis. This is an important observation in line with the systemic nature of the disease.

We present a new analytical method for thiol quantification in plasma, based on the use of capillary electrophoresis (CE) and laser-induced fluorescence (LIF) to analyze 6-iodoacetamidofluorescein derivatives. Quantitative results of homocysteine, glutathione, cysteinylglycine, and cystationine are presented. A comparison of the quantitation of homocysteine in plasma, using high performance liquid chromatography/fluorescence detection and fluorescence polarization immunoassay is proposed. The results indicate that these techniques for plasma total homocysteine (tHcy) determination can be used interchangeably. The major advantage of CE-LIF is that it can quantitate the thiols in one run while keeping the price of consumables reasonable.

The purpose of this study was to investigate in the rat heart and liver the effects of an acute administration of three anthracyclines, doxorubicin, epirubicin and pirarubicin, and an anthracenedione, mitoxantrone, on the membrane peroxidative status, which was estimated by the composition of polyunsaturated fatty acids (PUFA), and on the activities of the enzymes involved in membrane repair processes and lipid hydroperoxide detoxification. Rats were injected for four consecutive days with the drugs or saline (control) and killed 24 hr after the last injection. All the drugs induced an increase in plasma thiobarbituric reactive substances and alpha-tocopherol concentrations, both expressed per milligram of plasma lipids. Plasma vitamin A was decreased by about a factor of two by all the drugs. The fatty acid profile in the heart lipids showed that the polyunsaturated species (20:4 n-6, 22:6 n-3) remained at the same or even higher levels after anthracycline treatment. This can be explained by the fact that the activities of the enzymes involved in either the recycling of membrane phospholipids, such as phospholipases A1 and A2 (EC 3.1.1.4 and EC 3.1.1.32), lysophospholipases (EC 3.1.1.5) and acylCoA:lysophosphatidylcholine acyltransferases (EC 2.3.1.23), or hydroperoxide detoxification, such as selenium-dependent glutathione peroxidase (GSH-PX, EC 1.11.1.9) and glutathione S-transferases (GSH-T, EC 2.1.5.18), were maintained at the same level of activity after the antitumoral treatment. In liver, membrane phospholipid levels of PUFA were maintained as well as the activities of phospholipid-metabolizing enzymes. GSH-PX activity was not affected whereas that of GSH-T was slightly lowered by the drugs. These results suggest that during acute antitumoral-induced lipid peroxidation of membranes, the multi-enzymatic complex of the immediate processes of repair and detoxification is fully operational, allowing the membrane to rapidly recover its functional status. The results are discussed in the context of the equivocal relationships between antitumoral-induced lipid peroxidation and cardiac disturbances.

The renin angiotensin system is a negative feed-back system of blood pressure control. A number of concordant experimental and clinical results indicate that the angiotensin family has a trophic effect on the vessel wall. These properties of the angiotensins favorise the proliferation of the cells which make up the vessel wall and also amplify the vascular dysfunction in the absence of the inhibitory regulations. Angiotensin converting enzyme inhibitors could be a valuable therapeutic method of counteracting these deleterious effects on the composition and function of the vessel wall.

Early onset vascular disease unexplained until today by usual risk factors (hyperlipidemia, hypertension, tobacco, stress), can now find an explanation in sulfur amino acid metabolism defect. By transsulfuration, alimentary methionine leads to homocysteine, which is itself turn into cysteine, or remethylated into methionine. Several abnormalities of these different pathways lead to plasma accumulation of homocysteine, which will be responsible of arterial or venous occlusive lesions, concerning peripheral or deep vessels. Homocysteine stays in plasma upon several forms: 75% being linked by disulfide bounds to proteins, 22% as disulfide, homocystine (homocysteine-homocysteine) or mixed-disulfide (homocysteine-cysteine), and less than 3% as free reduced homocysteine. Plasma reduction allows total homocysteine evaluation with amino acid autoanalyzer. The basal plasma homocysteine level is less than 14 microMl. However, levels near this basal value can be found in patients with latent abnormality, which needs to be revealed by a methionine loading test. This study concerns two methodologies and their application to the exploration of a patient with unidentified neurologic disorders. The first one describes a new galenic oral form of methionine. Other authors use the methionine load of 100 mg/kg dissolving it in a fruit juice glass. In order to obtain a complete dissolution of this weakly soluble substance and to ensure its total absorbtion by the patient, we prepare a granular form aimed to give in water a perfect flavoured suspension. The second methodology concerns methionine loading test and amino acid analysis. After 10 hours fasting, a 100 mg/kg peroral methionine load is realized performing 5 EDTA blood samples before and 4, 8, 12 and 24 hours after loading.(ABSTRACT TRUNCATED AT 250 WORDS)

Increasing dietary fish oil in rat had the following effect on brain lipids: Arachidonic acid regularly decreased; eicosapentanenoic acid, normally nearly undetectable, was present; 22:5(n - 3), dramatically increased but remained below 1% of total fatty acids; cervonic acid was increased by 30% at high fish oil concentration. Saturated and monounsaturated fatty acids were not affected regardless of chain-length. In contrast, in the liver, nearly all fatty acids (saturated, monounsaturated and polyunsaturated) were affected by high dietary content of fish oil, but liver function was normal: serum vitamin A and E, glutathione peroxidase, alkaline phosphatase, transaminases were not affected. Serum total cholesterol, unesterified cholesterol and phosphatidylcholine were slightly affected. In contrast, triacylglycerols were dramatically reduced in proportion to the fish oil content of the diet.

The existence of a relation between vitamin A and vitamin E and human cancers is supported by epidemiologic investigations. The aim of this study is to link the level of these vitamins to those of plasmatic protein carriers like retinol binding protein (RBP) and prealbumin (TTR), in three groups of subjects: healthy patients (n = 78), polyp (n = 34) and digestive cancer patients (n = 70). A paired t-test did not reveal any significant variation in any parameter between the polyp group and controls, but did evidence a significant decrease in serum levels of retinol (p less than 2.10(-4], RBP (p less than 2.10(-4), TTR (p less than 10(-5), and alpha-tocopherol (p less than 2.10(-3), in cancer cases as against control subjects. Comparison of RBP renal clearance and retinol tissue clearance in cancer and healthy patients indicates that the decrease in circulating retinol levels cannot be attributed to an increase in peripheral consumption. The simultaneous reduction of RBP and TTR serum levels is to be considered as a sign of protein denutrition. Thus our results suggest that the decrease serum levels of vitamins A and E observed in digestive cancers are a consequence of this nutritional deficiency.

The prognosis of spastic angina is difficult to determine. The object of this study was to try to evaluate the prognosis of coronary spasm on the results of provocative, ergometrine testing. Out of 708 patients with angiographically normal or near-normal coronary arteries undergoing the ergometrine test for assessment of chest pain, 78 patients with positive results were retained for study. The threshold of spasm was established in every case: this was defined as the quantity of ergometrine per kilogramme body weight required to provoke spasm. The values ranged from 1 to 12.5 micrograms/kg (average 7.58 micrograms/kg +/- 3.84). The reproducibility of the ergometrine test appeared to be very satisfactory. In the short term, only 4 out of 32 tests became negative. The test remained positive in 28 cases and the mean value of the threshold of spasm did not change significantly (5.64 +/- 3.27 to 5.52 +/- 3.18 micrograms/kg). In the long term only 2 out of 18 tests became negative. The test remained positive in 16 cases and the mean value of the threshold of spasm did not change significantly (5.68 +/- 2.96 to 6.58 +/- 3.11 micrograms/kg). The ergometrine test with a reference threshold of positivity of 5 micrograms/kg is doubly useful: this threshold value helps predict a good response to calcium inhibitor drugs: the threshold of spasm was less than this value in 6 of the 41 patients whose tests became negative after diltiazem therapy, and in 12 of 14 patients in whom the test remained positive (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Limiting viscosity numbers of bovine and ovine erythrocytes carbonic anhydrase variants were calculated by the objective method of comparing viscosimetric data obtained from low-activity-human erythrocyte carbonic anhydrase and its natural variant. Shifts of mobilities and isoelectric points are shown for all species variants, but variations of limiting viscosity numbers were only detected for human and bovine variants. Results of the study are consistent with the observation that variants arise by deamidation of erythrocyte carbonic anhydrases, and that deamidation is responsible for changes in structure and hydration (i. e. "conformational" modifications). Thus, all the variants so far investigated are stable conformational variants or erythrocyte carbonic anhydrases.

In vitro lipolysis by adrenaline, adrenaline + phentolamine (alpha-blocker) and isoprenalin (beta-agonist) was studied in deltoid and trochanter adipose tissues of sixteen obese females (10 android and 6 gynoid). Lipolysis differs in the upper and lower parts of the body. The more the obesity predominates in the upper part of the body, the more this difference is significant. If the actions of adrenaline in gynoid obese women are identical in deltoid and trochanter adipose tissues, the alpha-antilipolytic effect is more powerful than the beta-antilipolytic effect on the trochanter adipose tissue of android obese women.

For 2 mo rats were fed a salmon oil diet (12.5%, wt/wt) supplemented with 4.5% (wt/wt) corn oil, a corn oil diet (17%, wt/wt) or a low fat diet (4.4%, wt/wt). Cardiac lipids were analyzed and fatty acid composition of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) was determined. Ventricular biopsies were taken for ultramicroscopic examination. Serum cholesterol, triglyceride, phospholipid and vitamin E concentrations were significantly lower in rats fed salmon oil than in those fed the other two diets, whereas serum transaminases and vitamin A were not significantly affected. Cardiac protein, phospholipid, triglyceride and cholesterol concentrations were unaffected by diet. Cardiac phospholipid composition remained unchanged and no significant changes in lyso-PC or lyso-PE levels were observed. However, the salmon oil diet produced a markedly lower n-6/n-3 ratio in both PE and PC than in the other two diets. This was the result of replacement of n-6 polyunsaturated fatty acids (PUFA), primarily 20:4n-6 with n-3 PUFA, primarily 22:6n-3. The unsaturation index of PC and PE was higher with the salmon oil diet than with the other two diets. Ventricular biopsies of rats fed salmon oil showed mild lipid accumulation associated with some lipofuscin-like material. It is suggested that, in rat heart, fish oil led to a moderate accumulation of lipids, the composition of which may include long-chain monounsaturated fatty acids and a degradative form of peroxidized lipids.