Glucuronidation of oxidized fatty acids and prostaglandins B1 and E2 by human hepatic and recombinant UDP-glucuronosyltransferases

Arachidonic acid (AA) can be metabolized to various metabolites, which can act as mediators of cellular processes. The objective of this work was to identify whether AA, prostaglandin (PG) B1 and E2, and 15- and 20-hydroxyeicosatetraenoic acids (15- and 20-HETE) are metabolized via glucuronidation. Assays with human recombinant UDP-glucuronosyltransferase 1A (UGT1A) isoforms revealed that AA and 15-HETE were glucuronidated by UGT1A1, 1A3, 1A4, 1A9, and 1A10, whereas 20-HETE was glucuronidated by UGT1A1 and 1A4 and PGB1 was glucuronidated by UGT1A1, 1A9, and 1A10. All substrates were glucuronidated by recombinant UGT2B7, with AA and 20-HETE being the best substrates. Kinetic analysis of UGT1A1 and 1A9 with AA resulted in Km values of 37.9 and 45.8 microM, respectively. PGB1 was glucuronidated by UGT1A1 with a Km of 26.3 microM. The Km values for all substrates with UGT2B7 were significantly higher than with the UGT1A isoforms. Liquid chromatography-mass spectrometry of glucuronides biosynthesized from PGB1 and 15-HETE showed that hydroxyl groups were the major target of glucuronidation. This work demonstrates a novel metabolic pathway for HETEs and PGs and the role of UGT1A isoforms in this process. These results indicate that glucuronidation may play a significant role in modulation of the availability of these fatty acid derivatives for cellular processes.     

MMS21/HPY2 and SIZ1, Two Arabidopsis SUMO E3 Ligases,Have Distinct Functions in Development

The small ubiquitin related modifier (SUMO)-mediated posttranslational protein modification is widely conserved among eukaryotes. Similar to ubiquitination, SUMO modifications are attached to the substrate protein through three reaction steps by the E1, E2 and E3 enzymes. To date, multiple families of SUMO E3 ligases have been reported in yeast and animals, but only two types of E3 ligases have been identified in Arabidopsis: SAP and Miz 1 (SIZ1) and Methyl Methanesulfonate-Sensitivity protein 21 (MMS21)/HIGH PLOIDY 2 (HPY2), hereafter referred to as HPY2. Both proteins possess characteristic motifs termed Siz/PIAS RING (SP-RING) domains, and these motifs are conserved throughout the plant kingdom. Previous studies have shown that loss-of-function mutations in HPY2 or SIZ1 cause dwarf phenotypes and that the phenotype of siz1-2 is caused by the accumulation of salicylic acid (SA). However, we demonstrate here that the phenotype of hpy2-1 does not depend on SA accumulation. Consistently, the expression of SIZ1 driven by the HPY2 promoter does not complement the hpy2-1 phenotypes, indicating that they are not functional homologs. Lastly, we show that the siz1-2 and hpy2-1 double mutant results in embryonic lethality, supporting the hypothesis that they have non-overlapping roles during embryogenesis. Together, these results suggest that SIZ1 and HPY2 function independently and that their combined SUMOylation is essential for plant development.     

Functional Subdivision of Group-ICA Results of fMRI Data Collected during Cinema Viewing

Independent component analysis (ICA) can unravel functional brain networks from functional magnetic resonance imaging (fMRI) data. The number of the estimated components affects both the spatial pattern of the identified networks and their time-course estimates. Here group-ICA was applied at four dimensionalities (10, 20, 40, and 58 components) to fMRI data collected from 15 subjects who viewed a 15-min silent film ("At land" by Maya Deren). We focused on the dorsal attention network, the default-mode network, and the sensorimotor network. The lowest dimensionalities demonstrated most prominent activity within the dorsal attention network, combined with the visual areas, and in the default-mode network; the sensorimotor network only appeared with ICA comprising at least 20 components. The results suggest that even very low-dimensional ICA can unravel the most prominent functionally-connected brain networks. However, increasing the number of components gives a more detailed picture and functionally feasible subdivision of the major networks. These results improve our understanding of the hierarchical subdivision of brain networks during viewing of a movie that provides continuous stimulation embedded in an attention-directing narrative.     

Malnutrition may affect common sole (Solea solea L.) growth, pigmentation and stress response: molecular, biochemical and histological implications

In the last decades there have been several evidences that traditionally used live preys like rotifers and Artemia salina have nutritional deficiencies that result in a general decrease of fish health, causing anomalies in the development, in growth and in pigmentation. In this study a partial of total replacement of traditional live preys with preserved copepods that represent the natural food of the larvae was evaluated during Solea solea culture. In this study a positive effect of co-feeding preserved copepods in sole larviculture was observed since larvae fed this diet growth and survived better, showed a better tolerance to captive conditions and had a better response to the final thermal/density stress-test with respect to larvae fed a traditional diet. Morphometric data were fully supported by molecular and biochemical ones. Moreover, liver histological investigations, revealed that the inclusion of preserved copepods in the larval diet was able to improve lipid assimilation. In conclusion, preserved copepods may be considered a suitable food for sole when used as a supplement to the traditional diet based on rotifers and Artemia nauplii.     

Genetic profiling using genome-wide significant coronary artery disease risk variants does not improve the prediction of subclinical atherosclerosis: the Cardiovascular Risk in Young Finns Study, the Bogalusa Heart Study and the Health 2000 Survey--a meta-analysis of three independent studies

Background

Genome-wide association studies (GWASs) have identified a large number of variants (SNPs) associating with an increased risk of coronary artery disease (CAD). Recently, the CARDIoGRAM consortium published a GWAS based on the largest study population so far. They successfully replicated twelve already known associations and discovered thirteen new SNPs associating with CAD. We examined whether the genetic profiling of these variants improves prediction of subclinical atherosclerosis – i.e., carotid intima-media thickness (CIMT) and carotid artery elasticity (CAE) – beyond classical risk factors.

Subjects and Methods

We genotyped 24 variants found in a population of European ancestry and measured CIMT and CAE in 2001 and 2007 from 2,081, and 2,015 subjects (aged 30–45 years in 2007) respectively, participating in the Cardiovascular Risk in Young Finns Study (YFS). The Bogalusa Heart Study (BHS; n = 1179) was used as a replication cohort (mean age of 37.5). For additional replication, a sub-sample of 5 SNPs was genotyped for 1,291 individuals aged 46–76 years participating in the Health 2000 population survey. We tested the impact of genetic risk score (GRS_24SNP/CAD) calculated as a weighted (by allelic odds ratios for CAD) sum of CAD risk alleles from the studied 24 variants on CIMT, CAE, the incidence of carotid atherosclerosis and the progression of CIMT and CAE during a 6-year follow-up.

Results

CIMT or CAE did not significantly associate with GRS_24SNP/CAD before or after adjusting for classical CAD risk factors (p>0.05 for all) in YFS or in the BHS. CIMT and CAE associated with only one SNP each in the YFS. The findings were not replicated in the replication cohorts. In the meta-analysis CIMT or CAE did not associate with any of the SNPs.

Conclusion

Genetic profiling, by using known CAD risk variants, should not improve risk stratification for subclinical atherosclerosis beyond conventional risk factors among healthy young adults.     

Relationship between regulatory and type 1 T cells in dogs with oral malignant melanoma

Recent data suggest a decreased prevalence of IFN‐γ‐producing T lymphocytes (Type 1 T cells) in tumor‐bearing hosts. Moreover, it has been reported that Treg have a strong impact on the activation and proliferation of CD4 (+) and CD8 (+) lymphocytes; however, no previous reports have described the relationship between Treg and the progression of tumor, or Type 1 T cell populations in dogs with malignant tumor. In this study, the percentage of Treg, Th1, and Tc1 in the peripheral blood of dogs with oral malignant melanoma and healthy dogs was measured and compared. Although the percentages of Th1 and Tc1 in dogs with oral malignant melanoma were less than those in healthy dogs (Th1: P < 0.01, Tc1: P < 0.05), the percentage of Treg was increased (P < 0.01). A significant inverse correlation between the percentage of Tc1 and the clinical tumor stage (P < 0.01), and a significant correlation between that of Treg and the clinical tumor stage (P < 0.001) was found. Moreover, there was a significant inverse correlation between the percentages of Treg and Th1 (P < 0.05) or Tc1 (P < 0.001). In conclusion, the percentage of Treg increases with the tumor stage in the peripheral blood of dogs with oral malignant melanoma. In dogs, Treg appears to suppress Type 1 immunity, which may be responsible for anti‐tumor responses.     

Production of hyperdorsal larvae by exposing uncleaved Xenopus eggs to a centrifugal force directed from the animal pole to the vegetal pole

Exposure of uncleaved Xenopus eggs to a centrifugal force directed from the animal pole to the vegetal pole produces larvae with enhanced dorsal structures, which resemble 'hyperdorso-anterior' larvae produced by D₂O-treatment at 0.3 normalized time (NT). Optimal conditions are 70 g for 6 min at 20% of the first cell cycle (0.2 NT). Exposure before removal of vegetal pole cortical cytoplasm, which we find has an effect of eliminating dorsal structures, protects eggs from losing their ability to form dorsal axial structures upon removal. In contrast, exposure after a slight ultraviolet (UV)-irradiation, which has virtually no effect on dorsal development, produces larvae with heavily reduced dorsal structures, which resemble 'ventralized' larvae produced by heavy UV-irradiation. Interestingly, none of these treatments prevents cortical rotation. Morphological and histological examinations reveal that exposure to the force causes displacement of both cortical and deep egg components from around the vegetal pole to subequatorial regions. We conclude that exposure to the centrifugal force enhances dorsal structures by displacing dorsal determinants from around the vegetal pole to subequatorial regions broader than normal. This is the first experiment in which displacement of egg components, by methods independent of the rotation, are shown to perturb larval body pattern.     

Effects of soil moisture stress on the growth and yield of Spanish variety peanut

Summary Greenhouse grown Spanish variety peanut was subjected to soil moisture stress during the early flowering and pod formation growth stages. Vegetative growth was not significantly reduced by the moisture stress. Primary root length and the number of pods produced were significantly reduced. However, there was no difference between the two stress treatments.