Immunocytochemical characterisation of olfactory ensheathing cells of zebrafish

Continuous lifelong neurogenesis is typical of the vertebrate olfactory system. The regenerative ability of olfactory receptor neurons is dependent on the glial cell type specific to the olfactory pathway, designated ‘olfactory ensheathing cells’. Several studies to date have focused on mammalian olfactory ensheathing cells, owing to their potential roles in cell‐based therapy for spinal cord injury repair. However, limited information is available regarding this glial cell type in non‐mammalian vertebrates, particularly anamniotes. In the current immunocytochemical study, we analysed the features of olfactory ensheathing cells in the zebrafish, Danio rerio. Fish provide a good model for studying glial cells associated with the olfactory pathway of non‐mammalian vertebrates. In particular, zebrafish has numerous valuable features that enable its use as a prime model organism for genetic, neurobiological and developmental studies, as well as toxicology and genomics research. Paraffin sections from decalcified heads of zebrafish were processed immunocytochemically to detect proteins used in the research on mammalian olfactory ensheathing cells, including glial fibrillary acid protein (GFAP), S100, neural cell adhesion molecule (NCAM), polysialylated NCAM (PSA‐NCAM), vimentin (VIM), p75NTR and galactin (Gal)‐1. Notably, GFAP, S100, NCAM and Gal‐1 were clearly observed, whereas no vimentin staining was detected. Weak immunostaining for PSA‐NCAM and p75NTR was evident. Moreover the degree of marker expression was not uniform in various tracts of the zebrafish olfactory pathway. The immunostaining patterns of the zebrafish olfactory system are distinct from those of other fish to some extent, suggesting interspecific differences. We also showed that the olfactory pathway of zebrafish expresses markers of mammalian olfactory ensheathing cells. The olfactory systems of vertebrates have similarities but there are also marked variations between them. The issue of whether regional and interspecific differences in immunostaining patterns of olfactory pathway markers have functional significance requires further investigation.     

Assessment of lifestyle effect on oxidative stress biomarkers in free‐living elderly in rural Japan

Background: Oxidative stress is believed to play a crucial role in aging and age‐related diseases, and is widely thought to increase morbidity and mortality in the elderly. Assessment of biomarkers of oxidative stress, such as 8‐isoprostane and 8‐hydroxy‐2‐deoxyguanosine, are considered to be useful in predicting disease risks at the population level. Objective: The aim of the present study was to assess the health status of the elderly by comparing their lifestyles and levels of oxidative stress biomarkers. Methods: We carried out a cross‐sectional study where urine samples from a total of 100 elderly men and women were assayed for 8‐isoprostane, 8‐hydroxy‐2‐deoxyguanosine, selenium, cadmium and creatinine. They were asked to answer a questionnaire that included questions about their lifestyle. Results: Most of the participants were prehypertensive, non‐alcohol users and on a rich plant‐based diet. There were no differences in any biomarkers of oxidative stress between men and women. 8‐Isoprostane was found to correlate positively with systolic blood pressure in women, but not in men. There was a slight increase of 8‐isoprostane in participants with a poor intake of vegetables, and a decrease of 8‐hydroxy‐2‐deoxyguanosine in participants who consumed fish. Multiple regression analysis showed that oxidative stress biomarkers were positively associated with cadmium, and negatively associated with selenium and fish intake in all participants, 89% of which were non‐smokers. Conclusion: Results from the present study show that fish intake has the potential of decreasing oxidative stress among elderly persons. Geriatr Gerontol Int 2012; 12: 547–554.     

Penetrating injury of the cornea by a barbed fish hook and its surgical management by “Cut-it out technique”

Fishing is a worldwide pastime enjoyed by millions of people. Ocular fishing injuries though uncommon may cause potentially devastating ocular trauma. We report a rare case of penetrating injury of the cornea by a barbed fish hook and its successful surgical management by “cut-it out technique”. We are discussing the various techniques available for removal of fish hooks. The hook can be successfully removed with minimal trauma to ocular structures by understanding the structure of the fish hook and by employing the appropriate method of extraction.     

In vitro evaluation of the metabolic stability of nine fragrance chemicals in trout and human hepatocytes

In vitro metabolic stability of nine fragrance chemicals: p-tolyl acetate, cashmeran, ethylene brassylate, celestolide, galaxolide, traseolide, ambretone, tonalide and pentadecanolide, was evaluated in trout and human hepatocytes. The compounds were incubated with trout hepatocytes at 12°C and human hepatocytes at 37°C. Quantification of compound disappearance with time was performed using gas chromatography/mass spectrometry. in vivo hepatic intrinsic clearance values were calculated from the in vitro data. Significant metabolism was observed with trout hepatocytes for five of the nine fragrance chemicals, while all nine were metabolized significantly with human hepatocytes. Previously published models were used to examine expected bioaccumulation and persistence in whole organisms. Calculated half-lives due to metabolism of the nine chemicals are significantly shorter for humans than trout: <1 hour and <1 day, respectively. For all chemicals with demonstrated hepatic metabolism, the models indicate a lack of accumulation. For those where metabolism was demonstrated in trout, calculated bioconcentration factors would not be classified as bioaccumulative under prevailing regulatory systems.     

Does Periconceptional Fish Consumption by Parents Affect the Incidence of Autism Spectrum Disorder and Intelligence Deficiency? A Case-control Study in Tianjin,China

Objective This study aimed to explore the association between periconceptional fish consumption by parents and autism spectrum disorder (ASD) and intelligence deficiency (ID). Methods A case-control study was conducted through a questionnaire with 108 ASD cases, 79 ID cases, and 108 controls. The ASD and ID cases were students from special educational schools in Tianjin from 2012 to 2014. The age- and sex-matched controls were from a high school, three primary schools, and a kindergarten in Tianjin. Multivariate logistic regression was performed. Results Paternal habit of eating hairtail before fertilization, maternal preference for fruits during pregnancy, and maternal habit of eating grass carp during pregnancy were preventive factors for ASD. Paternal habit of drinking alcohol before fertilization was a risk factor for ID, whereas maternal preference for fruits during pregnancy and maternal habit of eating crucian carp during pregnancy were protective factors for ID. Conclusion Parental fish consumption is beneficial for the prevention of ASD and ID. Meanwhile, the protective effects of fish consumption on ASD and ID differ. More attention should be paid to the combined effect of other food when eating fish.     

Mercury,omega-3 fatty acids,and seafood intake are not associated with heart rate variability or QT interval

Mercury (Hg), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) concentrations differ across seafood types. Our aim was to investigate the association of Hg, EPA, and DHA, as well as avid consumption of diverse seafood types, with cardiovascular variables heart rate variability (HRV) and QT interval duration (QTc) in a contemporary population. We measured HRV and QTc by Holter monitor, EPA and DHA in plasma, total Hg in whole blood, and possible confounders in 94 avid seafood consumers from Long Island, NY. Participants had mean Hg of 8.4 mcg/L, mean EPA of 1.2%, and mean DHA of 3.7% of total fatty acids. Adjusted for possible confounders, EPA+DHA, Hg, and total seafood consumption were not associated with HRV or QTc. Associations with consumption of specific seafood types were suggested (eg, tuna steak with QTc and anchovies with HRV) but require verification.     

Dietary intake in people consuming a low‐carbohydrate diet in the UK Biobank

Background

Low‐carbohydrate diets are becoming increasingly popular, although their dietary quality outside of clinical studies is unknown. A previous study analysed the dietary intake in people consuming a reduced‐carbohydrate diet (<40% calories). However, it is not clear what foods people consume when carbohydrate is reduced to below 26% of total calories.

Methods

In the present cross‐sectional study, the dietary and nutrient intake collected via up to five consecutive 24‐h dietary recalls and a food frequency questionnaire of 444 individuals (aged 46‐79 years) consuming <26% of calories from carbohydrate (LCHO ) was compared with that of 131 897 individuals consuming ≥45% calories from carbohydrate (NCHO ) using the UK Biobank Dataset. Absolute cut‐offs to define the low‐carbohydrate group (<130 g day^–1; n  = 1953 versus ≥225 g day^–1, n  = 113 036) were also used.

Results

Both NCHO (>45% calories and ≥225 g) groups consumed significantly more high‐sugar, high‐fat snacks [median 6.0, interquartile range (IQR ) = 2.0–11.0 and median 6.0, IQR  = 3.0–11.8, respectively) compared to the LCHO (<26% calories and <130 g) groups (median 0, IQR  = 0–2.8 and median 1, IQR  = 0–3.8, respectively) (P  < 0.0001). Both LCHO groups reported consuming significantly more red meat, oily fish, nuts and seeds but fewer fruits, vegetables and pulses compared to the NCHO groups. In general, the consumption of oily fish, nuts, seeds and pulses was low across the whole cohort and differences in intake between the LCHO and NCHO groups were small. After adjusting for socio‐economic status, most differences remained.

Conclusions

Carbohydrate restriction is associated with both beneficial and potentially deleterious dietary changes compared to a normal carbohydrate intake.

     

A subchronic in situ exposure method for evaluating effects in small‐bodied fish at contaminated sites

In situ fish‐caging studies at contaminated sites can provide information that is more realistic compared to traditional laboratory‐based studies. However, few methods have been developed for exposing sentinel fish species for subchronic durations, and fewer still are optimized for exposing small‐bodied fish while maintaining fish health and growth throughout the caging trial. Those methods typically lack a feeding regimen during the fish caging trial. While that may be acceptable or even appropriate for typical short‐term toxicity testing, it does limit the duration of the exposure, and may not be suitable when post‐caging trials or observations are necessary. Returning healthy fish to the lab following the in situ exposure would be important, for example, in studies designed to examine long‐term or multigenerational effects following an in situ exposure. In this article we describe a subchronic method for caging small fish at contaminated sites while maintaining growth and reproductive development. Fathead minnow (Pimephales promelas) were caged in situ for 6 weeks, after which time they were returned to the lab where they were evaluated for health and reproductive performance. Growth and reproductive endpoints revealed no adverse effect on fish due to fish caging and related handling, demonstrating the suitability of our caging and feeding method for long‐term caging studies. © 2011 Wiley Periodicals, Inc. Environ Toxicol 29: 54–63, 2014.     

Effects of quercetin and fish n‐3 fatty acids on testicular injury induced by ethanol in rats

The aim of this study was to investigate the effects of quercetin and fish n‐3 fatty acids on the changes in testis induced by ethanol. Forty‐five rats divided into five groups, control, ethanol, ethanol+quercetin, ethanol+fish n‐3 fatty acids and ethanol+quercetin+fish n‐3 fatty acids. At the end of 8 weeks, all the rats were sacrificed. Degenerative changes in histopathological analyses, the decreased body weight gain and seminiferous tubule diameters in ethanol group have been observed. TUNEL assay also showed an increase in apoptotic cell number. The activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH‐Px), xanthine oxidase (XO) and testosterone levels were decreased as well as the levels of malondialdehyde (MDA) and nitric oxide (NO) were increased in ethanol group. Histopathological changes caused by ethanol have been improved by quercetin and fish n‐3 fatty acids. It was also found that protection was provided by increasing SOD, CAT and GSH‐Px activities in groups administered quercetin, fish n‐3 fatty acids and quercetin+fish n‐3 fatty acids, and by decreasing the levels of MDA and NO in groups administered both quercetin and fish n‐3 fatty acids together. These results suggest that quercetin and fish n‐3 fatty acids are beneficial agents to reduce testicular injury induced by ethanol except for testosterone levels.     

Reduced Anxiety in Forensic Inpatients after a Long-Term Intervention with Atlantic Salmon

The aim of the present study was to investigate the effects of Atlantic salmon consumption on underlying biological mechanisms associated with anxiety such as heart rate variability (HRV) and heart rate (HR) as well as a measure of self-reported anxiety. Moreover, these biological and self-reported outcome measures were investigated in relation to specific nutrients; vitamin D status, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Ninety-five male forensic inpatients were randomly assigned into a Fish (Atlantic salmon three times per week from September to February) or a Control group (alternative meal, e.g., chicken, pork, or beef three times per week during the same period). HRV measured as the root mean square of successive differences (rMSSD), HR, state- and trait-anxiety (STAI), were assessed before (pre-test) and at the end of the 23 weeks dietary intervention period (post-test). The Fish group showed significant improvements in both rMSSD and HR. The Fish group also showed significant decreases in state-anxiety. Finally, there was a positive relationship between rMSSD and vitamin D status. The findings suggest that Atlantic salmon consumption may have an impact on mental health related variables such as underlying mechanisms playing a key role in emotion-regulation and state-anxiety.