Consumption of Argan Oil Improves Anti‐Oxidant and Lipid Status in Hemodialysis Patients

Objective: Virgin Argan oil (VAO) is of interest in oxidative stress and lipid profile because of its fat composition and antioxidant compounds. We investigated the effect of VAO consumption on lipid profile and antioxidant status in hemodialysis patients after a 4‐week period of consumption. Methods: In a crossover, controlled trial, 37 patients (18 men, 19 women) with end‐stage renal disease on maintenance hemodialysis, were randomly assigned to a 4‐week VAO diet. Fasting plasma lipids, vitamin E and oxidized LDL (ox‐LDL) were analyzed. Malondialdehyde (MDA) was determined before and after hemodialysis session. Results: There was no significant change in serum total cholesterol and ox‐LDL. However, VAO consumption decreased the levels of triglyceride (p = 0.03), total cholesterol (p = 0.02) and low‐density lipoprotein (p = 0.03) and increased the levels of high‐density lipoprotein (p = 0.01). Plasma vitamin E contents significantly increased from baseline only in VAO‐group (p < 0.001). Hemodialysis session increased MDA levels, but the increase in VAO group was less than in control group. Conclusion: VAO consumption improved lipid profile and oxidative stress status in hemodialysis patients. Copyright © 2015 John Wiley & Sons, Ltd.     

Cystadénome Papillaire de L’épididyme: Un Nouveau Cas

Papillary cystadenoma of the epididymis is a rare benign neoplasm that arises from the efferent duct epithelium. It may show as a unilateral or bilateral epididymal mass and its association with von Hippel-Lindau syndrome is very high, particularly in bilateral lesions. A 36-year-old male presented with a left-side scrotal mass of one year duration. On local examination, a painless irregular and hard testicular mass. Ultrasonography of the scrotum revealed a left strong hypoechoic, homogeneous, well limited testicular mass of 30×25×22mm diameter. The tumorous scorers were normal (beta HCG and AFP). The testicular mass was explored through a left inguinal incision. In palpation, it is a hard testicular tumor. Left Orchidectomy is carried out. The pathologic examination reveals a serous papillary cystadenoma borderline paratesticular without sign of invasion. We propose guidelines from literature for diagnosis, histogenesis and treatment of this rare tumor.     

Spindle poisons can induce polyploidy by mitotic slippage and micronucleate mononucleates in the cytokinesis-block assay

The human in vitro cytokinesis–blocked micronucleus (MN)assay has been extensively used for detection of clastogenicand aneugenic agents. In this test binucleate cells are generallyconsidered to be the main target cell population for assessinggenotoxic effect and almost no attention is paid to the biologicalinformation contained in mononucleate cells. In this study weanalysed the frequencies of micronucleate mononucleates in acontrol population and after in vitro exposure to clastogensor aneugens. A clear increase in MN in mononucleates was foundonly after exposure to aneugenic compounds. By means of fluorescencein situ hybridization using a chromosome 1–specific probewe further analysed the proportion of mononucleate cells withand without MN which were tetrasomic (tetraploid) and wouldhave been induced during aneugen treatment by mitotic slippage.The data indicate that treatment with nocodazole induces tetrasomyfor chromosome 1 (tetraploidy) and an increase in MN frequencyin mononucleate diploid and tetraploid lymphocytes. The resultsthus confirm that some mononucleates pass mitosis without chromatidsegregation to daughter nuclei. These data suggest that MN inmononucleates may be useful to distinguish clastogens from aneugensand increase the sensitivity of the test. ¹To whom correspondence should be addressed. Tel: +32 2 6293529; Fax: +32 2 6293408; Email: aelhajou{at}vub.ac.be     

Metabolic differences between whole blood and isolated lymphocyte cultures for micronucleus (MN) induction by cyclophosphamide and benzo[a]pyrene

In order to study the metabolic differences between whole bloodand isolated lymphocyte cultures, two indirectly acting mutagenscyclophosphamide (CP) and benzo[a]pyrene (B[a]P) were assessedfor their potential to induce micronuclei (MN) in the presenceand absence of S9 microsomal fractions. In isolated lymphocytecultures supplemented with S9, CP and B[a]P induced a statisticallysignificant increase in MN which was not observed in whole bloodcultures. However, the directacting agent methyl methanesulphonate(which was used as a positive control) showed an increase inMN frequency in a dose-dependent manner in both culture methods.The effect of erythrocytes was then investigated by treatingisolated lymphocyte cultures simultaneously with CP and S9 mixin the presence of purified erythrocyte concentrate (PEC). Aclear reduction in the MN frequency was observed compared tothe frequencies of MN induced in isolated lymphocyte culturestreated with CP and S9 mix in the absence of PEC. Thus, isolatedlymphocyte cultures may represent a more sensitive test systemfor the evaluation of potential indirectacting mutagens. However,whole blood cultures may reflect the ‘real life’situation more accurately as a consequence of the presence oferythrocytes.     

Chromogranin a induces the biogenesis of granules with calcium- and actin-dependent dynamics and exocytosis in constitutively secreting cells

Chromogranins are a family of acidic glycoproteins that play an active role in hormone and neuropeptide secretion through their crucial role in secretory granule biogenesis in neuroendocrine cells. However, the molecular mechanisms underlying their granulogenic activity are still not fully understood. Because we previously demonstrated that the expression of the major component of secretory granules, chromogranin A (CgA), is able to induce the formation of secretory granules in nonendocrine COS-7 cells, we decided to use this model to dissect the mechanisms triggered by CgA leading to the biogenesis and trafficking of such granules. Using quantitative live cell imaging, we first show that CgA-induced organelles exhibit a Ca(2+)-dependent trafficking, in contrast to native vesicle stomatitis virus G protein-containing constitutive vesicles. To identify the proteins that confer such properties to the newly formed granules, we developed CgA-stably-expressing COS-7 cells, purified their CgA-containing granules by subcellular fractionation, and analyzed the granule proteome by liquid chromatography-tandem mass spectrometry. This analysis revealed the association of several cytosolic proteins to the granule membrane, including GTPases, cytoskeleton-based molecular motors, and other proteins with actin- and/or Ca(2+)-binding properties. Furthermore, disruption of cytoskeleton affects not only the distribution and the transport but also the Ca(2+)-evoked exocytosis of the CgA-containing granules, indicating that these granules interact with microtubules and cortical actin for the regulated release of their content. These data demonstrate for the first time that the neuroendocrine factor CgA induces the recruitment of cytoskeleton-, GTP-, and Ca(2+)-binding proteins in constitutively secreting COS-7 cells to generate vesicles endowed with typical dynamics and exocytotic properties of neuroendocrine secretory granules.     

HUMN project initiative and review of validation,quality control and prospects for further development of automated micronucleus assays using image cytometry systems

The use of micronucleus (MN) assays in in vitro genetic toxicology testing, radiation biodosimetry and population biomonitoring to study the genotoxic impacts of environment gene-interactions has steadily increased over the past two decades. As a consequence there has been a strong interest in developing automated systems to score micronuclei, a biomarker of chromosome breakage or loss, in mammalian and human cells. This paper summarises the outcomes of a workshop on this topic, organised by the HUMN project, at the 6th International Conference on Environmental Mutagenesis in Human Populations at Doha, Qatar, 2012. The aim of this paper is to summarise the outcomes of the workshop with respect to the set objectives which were: (i) Review current developments in automation of micronucleus assays by image cytometry; (ii) define the performance characteristics of automated MN scoring using image cytometry and methods of assessment for instrument validation and quality control and (iii) discuss the design of inter-laboratory comparisons and standardisation of micronucleus assays using automated image cytometry systems. It is evident that automated scoring of micronuclei by automated image cytometry using different commercially available platforms [e.g. Metafer (MetaSystems), Pathfinder™ (IMSTAR), iCyte^® (Compucyte)], particularly for lymphocytes, is at a mature stage of development with good agreement between visual and automated scoring across systems (correlation factors ranging from 0.58 to 0.99). However, a standardised system of validation and calibration is required to enable more reliable comparison of data across laboratories and across platforms. This review identifies recent progress, important limitations and steps that need to be taken into account to enable the successful universal implementation of automated micronucleus assays by image cytometry.     

Influence of endothelial cells on vascular smooth muscle cells phenotype after irradiation: implication in radiation-induced vascular damages

Damage to vessels is one of the most common effects of therapeutic irradiation on normal tissues. We undertook a study in patients treated with preoperative radiotherapy and demonstrated in vivo the importance of proliferation, migration, and fibrogenic phenotype of vascular smooth muscle cells (VSMCs) in radiation-induced vascular damage. These lesions may result from imbalance in the cross talk between endothelial cells (ECs) and VSMCs. Using co-culture models, we examined whether ECs influence proliferation, migration, and fibrogenic phenotype of VSMCs. In the presence of irradiated ECs, proliferation and migration of VSMCs were increased. Moreover, expressions of alpha-smooth muscle actin, connective tissue growth factor, plasminogen activator inhibitor type 1, heat shock protein 27, and collagen type III, alpha 1 were up-regulated in VSMCs exposed to irradiated ECs. Secretion of transforming growth factor (TGF)-beta1 was increased after irradiation of ECs, and irradiated ECs activated the Smad pathway in VSMCs by inducing Smad3/4 nuclear translocation and Smad-dependent promoter activation. Using small interferring RNA targeting Smad3 and a TGFbeta-RII neutralizing antibody, we demonstrate that a TGF-beta1/TGF-beta-RII/Smad3 pathway is involved in the fibrogenic phenotype of VSMCs induced by irradiated ECs. In conclusion, we show the importance of proliferation, migration, and fibrogenic phenotype of VSMCs in patients. Moreover, we demonstrate in vitro that ECs influence these fundamental mechanisms involved in radiation-induced vascular damages.