Impaired sperm chromatin integrity in obese mice.

An increased global prevalence of obesity coincides with an apparent decline in male sperm quality and a possible association between these pathologies has been suggested. In this study, we examined the effects of obesity on sperm chromatin integrity using two mouse models of obesity. In one group of mice, obesity was induced by a high-fat diet (HFD) (diet-induced obesity; DIO model), whereas in the other group, leptin deficiency was used to study the effects of obesity independently of the influence of dietary factors. Sperm chromatin integrity is recognized as an important measure of male infertility, and was analysed by the sperm chromatin structure assay. We found increased sperm DNA fragmentation in both groups of obese mice compared to lean mice, whereas the percentage of immature spermatozoa was not increased by obesity. The DIO model reflects the human condition more closely than the leptin-deficient model and was therefore selected for examination of the transcriptional response of a selection of marker genes in the testis by quantitative real-time PCR. The analysis of transcript levels of the selected testicular marker genes showed moderate, but significant, up-regulation of the Cyp2e1, Cyp19a1, Tnf and Pparg genes in DIO mice compared to lean mice. In conclusion, a clear positive correlation between body mass index and sperm DNA fragmentation was found in two mouse models of obesity. However, the variability in sperm DNA fragmentation within the two groups of obese animals was high. The observed changes in the transcript level of the marker genes suggest that there may be a local response in testicular cells to the HFD regimen with a potential impact on intratesticular signalling and spermatogenesis.

Evaluation of the odd fatty acids 15:0 and 17:0 in serum and adipose tissue as markers of intake of milk and dairy fat.

BACKGROUND: There is a need for biomarkers of dietary saturated fatty acids, because several diseases have been related to intake of these fatty acids. OBJECTIVE: To examine the relation between intake of dairy fat and the proportion of pentadecanoic (15:0) and heptadecanoic (17:0) acid in serum and adipose tissue. DESIGN: Healthy men aged 21-55 y provided serum (n = 110) and adipose tissue samples (n = 107) and completed both 14 days weighed records (WR) and a 180-item food frequency questionnaire (FFQ). The proportions of 15:0 and 17:0 acid in serum and adipose tissue as measured by gas liquid chromatography were evaluated as biomarkers for fat intake from dairy products using Pearsons correlation coefficient and the method of triads. RESULTS: The strongest correlation coefficients were observed between total intake of dairy fat estimated from WR and relative content of 15:0 in adipose tissue (0.52, 95% CI: 0.37, 0.65) and total serum (0.43, 95% CI 0.26, 0.57). A consistent inverse association was observed between the intake of milk fat and relative serum content of 17:0. The validity coefficients observed for the intake of dairy fat estimated from weighed records, the 180-item FFQ and by the relative content of 15:0 in serum and adipose tissue were 0.94 (95% CI: 0.68, 1.00), 0.50 (95% CI: 0.29, 0.67), 0.49 (95% CI: 0.32, 0.67) and 0.56 (95% CI: 0.28, 0.82), respectively. CONCLUSION: Relative content of 15:0 in serum and adipose tissue may be a useful biomarker for the intake of total dairy fat, whereas FFQs and WRs may provide better estimates of the intake of fat from milk.

Modulation of COX-2 expression in peripheral blood cells by increased intake of fruit and vegetables?

BACKGROUND: Enhanced cyclooxygenase-2 (COX-2) expression is associated with carcinogenesis, ischemia, angiogenesis, inflammation, and neurodegeneration. The preventing effect of aspirin and nonsteroidal anti-inflammatory drugs is partly due to inhibition of the COX-2 enzyme. Fruit and vegetables (FVs) contain numerous compounds that may decrease disease risk by several different mechanisms, for example through the inhibition of COX-2 activity. OBJECTIVE: We tested the hypothesis that an increased intake of FVs would modulate the COX-2 expression in peripheral blood cells. DESIGN: A strictly controlled dietary crossover study (n = 39). After 1 week run-in period with no FVs in the diet, one group was given two portions of FVs (2 FV), while another group was given five portions (5 FV) daily for 14 days. Following a 2 weeks washout period and 1 week run-in, the regimens were switched between the groups. Gene expression analysis of COX-2 mRNA in blood samples was performed by quantitative real-time-PCR. RESULTS: No significant treatment effect of diet intervention was found in the crossover analyses (P = 0.74). However, the individual variation in response may seem large. CONCLUSIONS: These data does not contradict the recommendations for an increased intake of FVs. Further studies on expression directly and indirectly, through analysis of factors regulating and being regulated by COX-2, should be carried out. A first step would be to evaluate the correspondence between COX-2 mRNA expression and products of the COX pathway, like prostaglandins. Naturally occurring polymorphisms of COX-2 promoters and coding regions might contribute to functional variations and response to different diets. SPONSORSHIP: Norwegian Research Council, National Nutrition Council, Throne Holst Foundation for Nutrition Research, Freia Chokoladefabriks Medisinske Fond and the Norwegian Cancer Society.

Six carotenoids in plasma used to assess recommended intake of fruits and vegetables in a controlled feeding study.

BACKGROUND: There is a need for objective and universally applicable biomarkers for the intake of foods believed to affect human health. OBJECTIVE: The purpose of this feeding study was to test whether plasma concentrations of carotenoids could be used to distinguish recommended consumption of mixed fruits and vegetables (five a day) from the current national intake of fruits and vegetables (two a day). DESIGN: A strict crossover design was chosen to correct for observed interindividual variations in carotenoid response. A total of 40 healthy subjects were included in the study. After 1 week run-in period with no fruits and vegetables in the diet, one group was given two portions (300 g) of fruits and vegetables daily, while another group was given five portions (750 g) for 14 days. Following a 2 week wash-out period and 1 week run-in, the regimens were switched between the groups. Fruits and vegetables were combined to match a typical Norwegian diet. RESULTS: Enhanced intake from two to five portions of mixed fruits and vegetables increased plasma concentrations of alpha-carotene (P=0.033) and lutein (P=0.051) in a crossover analysis. Analysis of data in the parallel part of the study revealed differences between the high and low intake for plasma concentrations of alpha-carotene (P=0.013) and beta-carotene (P=0.016). A trend was also evident for plasma concentrations of lycopene (P=0.057) and lutein (P=0.076) in the parallel analysis. No effect of high vs low intake of fruits and vegetables was observed for plasma concentrations of beta-cryptoxanthin, zeaxanthin, cholesterol and triacylglycerols. CONCLUSION: The study indicates that plasma concentration of alpha-carotene, beta-carotene and lutein may be used to assess changes of fruit and vegetable intake corresponding to an increase from the present national intake in Norway to the recommended amount of five portions of fruits and vegetables daily. SPONSORSHIP: Norwegian Research Council, National Nutrition Council, Throne Holst Foundation for Nutrition Research and Freia Chokoladefabriks Medisinske Fond.

Three-dimensional computerised atlas of the rat brain stem precerebellar system: approaches for mapping, visualization, and comparison of spatial distribution data.

Comparisons of microscopical neuroanatomic data from different experiments and investigators are typically hampered by the use of different section planes and dissimilar techniques for data documentation. We have developed a framework for visualization and comparison of section-based, spatial distribution data, in brain stem nuclei. This framework provides opportunities for harmonized data presentation in neuroinformatics databases. Three-dimensional computerized reconstructions of the rat brain stem and precerebellar nuclei served as a basis for establishing internal coordinate systems for the pontine nuclei and the precerebellar divisions of the sensory trigeminal nuclei. Coordinate based diagrams were used for presentation of experimental data (spatial distribution of labelled neurons and axonal plexuses) from standard angles of view. Each nuclear coordinate system was based on a cuboid bounding box with a defined orientation. The bounding box was size-adjusted to touch cyto- and myeloarchitectonically defined boundaries of the individual nuclei, or easily identifiable nearby landmarks. We exemplify the use of these internal coordinate systems with dual retrograde neural tracing data from pontocerebellar and trigeminocerebellar systems. The new experimental data were combined, in the same coordinate based diagrams, with previously published data made available via a neuroinformatics data repository (www.nesys.uio.no/Database, see also www.cerebellum.org). Three-dimensional atlasing, internal nuclear coordinate systems, and consistent formats for presentation of neuroanatomic data in web-based data repositories, offer new opportunities for efficient analysis and re-analysis of neuroanatomic data.

Characterization of the humoral immune response to porcine reproductive and respiratory syndrome (PRRS) virus infection.

The development of the humoral immune response against porcine reproductive and respiratory syndrome (PRRS) virus was monitored by an indirect fluorescent antibody (IFA) test, immunoperoxidase monolayer assay (IPMA), enzyme-linked immunosorbent assay (ELISA), and serum virus neutralization (SVN) test over a 105-day period in 8 pigs experimentally infected with ATCC strain VR-2402. Specific antibodies against PRRS virus were first detected by the IFA test, IPMA, ELISA, and the SVN test 9-11, 5-9, 9-13, and 9-28 days postinoculation (PI), respectively, and reached their maximum values by 4-5, 5-6, 4-6, and 10-11 weeks PI, respectively, thereafter. After reaching maximum value, all assays showed a decline in antibody levels. Assuming a constant rate of antibody decay, it was estimated by regression analysis that the ELISA, IFA, IPMA, and SVN antibody titers would approach the lower limits of detection by approximately days 137, 158, 324, and 356 PI, respectively. In this study, the immunoperoxidase monolayer assay appeared to offer slightly better performance relative to the IFA test, ELISA, and SVN test in terms of earlier detection and slower rate of decline in antibody titers. Western immunoblot analysis revealed that antibody specific for the 15-kD viral protein was present in all pigs by 7 days PI and persisted throughout the 105-day observation period. Initial detection of antibodies to the 19-, 23-, and 26-kD proteins varied among pigs, ranging from 9 to 35 days PI. Thereafter, the antibody responses to these 3 viral proteins of PRRS virus continued to be detected throughout the 105-day study period.(ABSTRACT TRUNCATED AT 250 WORDS)

Excretion of porcine reproductive and respiratory syndrome virus in semen after experimentally induced infection in boars.

Four boars intranasally inoculated with porcine reproductive and respiratory syndrome (PRRS) virus were monitored for 56 days after exposure for changes in semen characteristics and for the presence of virus in the semen. Clinically, 2 of 4 boars had mild respiratory signs of 1 day's duration after infection. Changes in appetite, behavior, or libido were not detected. All boars seroconverted on the indirect fluorescent antibody and serum virus neutralization tests by day 14 after inoculation. Virus was isolated from serum between days 7 and 14 after inoculation. During the monitoring period, semen volume decreased and pH correspondingly increased; however, this change began 7 to 10 days prior to infection. Differences in sperm morphologic features, concentration, or motility between the preinfection and postinfection samples were not observed. The PRRS virus was detected in semen at the first collection in each of the 4 boars (ie, 3 or 5 days after challenge exposure). Virus was detected in nearly all semen samples collected from the 4 infected boars through days 13, 25, 27, and 43, respectively. Neither gross nor microscopic lesions attributable to PRRS virus were observed in tissues collected at the termination of the experiment (day 56), and virus isolation results from reproductive tissues were negative.