We have hypothesized that dietary modulation of intestinal miRNA expression may contribute to the chemoprotective effects of nutritional bioactives (fish oil and pectin). Using a rat colon carcinogen model, we determined miRNAs-let-7d, miR-15b, miR-107, miR-191 and miR-324-5p were modulated by fish oil + pectin. We also demonstrated that BACE1 and PTEN are targets of miR-107 and miR-21, respectively. To further elucidate the biological effects of diet and carcinogen on miRNAs, we integrated global miRNAs, total and polysomal gene expression datasets obtained from the above mentioned study and used four computational approaches. We demonstrated that polysomal profiling is tightly related to microRNA changes when compared with total mRNA profiling. In addition, diet and carcinogen exposure modulated a number of microRNAs and complementary gene expression analyses showed that oncogenic PTK2B, PDE4B, and TCF4 were suppressed by the chemoprotective diet at both the mRNA and protein levels. To determine the function of select diet and colon carcinogen modulated miRNAs and to validate their targets, we carried out a series of loss and gain of function experiments along with luciferase reporter assays. We verified that PDE4B and TCF4 are direct targets of miR-26b and miR-203, respectively. PTK2B was determined to be an indirect target of miR-19b. In addition, microRNA physiological function was assessed by examining effects on apoptosis and cell proliferation. To better understand how the colonic stem cell population responds to environmental factors such as diet and carcinogen, we investigated the chemoprotective effects of dietary agents on miRNAs in colonic stem cells obtained from Lgr5-EGFP-IRES-creERT2 knock in mice injected with AOM. We demonstrated that based on relative expression of miR-125a-5p, miR-190b and miR-191 in stem cells vs. daughter cells and differentiated cells, these miRNAs may be stem cell specific miRNAs. We also identified miR-21 to be significantly reduced in stem cells compared to differentiated cells and selectively modulated by these dietary agents in stem cells. In summary, our results indicate for the first time that fish oil plus pectin protect against colon tumorigenesis in part by modulating a subset of miRNAs and their target genes (mRNAs) implicated in the regulation of the colon stem cell niche and tumor development.

A series of experiments were conducted to explore factors affecting transfer of value-added ingredients from the diet to table eggs, with the goal of contributing to improvements in the enrichment process. Flaxseed-based ω-3 PUFA enrichment did not reduce lutein enrichment. The combine enrichment of lutein and ω-3 PUFA had decresed lipid oxidation potential. Also, when fed a ω-3 PUFA diet, birds scored as energetic Efficient had longer and wider villi, resulting in greater absorptive surface area/villi than Non-efficient hens. However, histomorphological differences did not affect transfer of ω-3 PUFA from diet to egg. Finally, birds fed graded levels of ω-3 PUFA to characterize change in lipid profile of egg and blood plasma in time reached a plateau in total ω-3 PUFA/egg in 5.9 to 6.6d, with High birds reaching the target of 300 mg/egg in 5d. Egg enrichment can be modulated by changes to the hen diet. / Animal Science

No description available.

no / Background: Skin cancer is a major public health concern, and the majority of cases are caused by solar ultraviolet radiation (UVR) exposure, which suppresses skin immunity. Omega-3 (n−3) PUFAs protect against photoimmunosuppression and skin cancer in mice, but the impact in humans is unknown. Objectives: We hypothesized that EPA-rich n−3 PUFA would abrogate photoimmunosuppression in humans. Therefore, a nutritional study was performed to assess the effect on UVR suppression of cutaneous cell-mediated immunity (CMI) reflected by nickel contact hypersensitivity (CHS). Design: In a double-blind, randomized controlled study, 79 volunteers (nickel-allergic women, 22–60 y old, with phototype I or II) took 5 g n−3 PUFA–containing lipid (70% EPA plus 10% DHA) or a control lipid daily for 3 mo. After supplementation, nickel was applied to 3 skin sites preexposed on 3 consecutive days to 1.9, 3.8, or 7.6 J/cm2 of solar-simulated radiation (SSR) and to 3 unexposed control sites. Nickel CHS responses were quantified after 72 h and the percentage of immunosuppression by SSR was calculated. Erythrocyte [red blood cell (RBC)] EPA was measured by using gas chromatography. Results: SSR dose-related suppression of the nickel CHS response was observed in both groups. Photoimmunosuppression appeared less in the n−3 PUFA group than in the control group (not statistically significant [mean difference (95% CI): 6.9% (−2.1%, 15.9%)]). The difference was greatest at 3.8 J/cm2 SSR [mean difference: 11% (95% CI: 0.5%, 21.4%)]. Postsupplementation RBC EPA was 4-fold higher in the n−3 PUFA group than in the control group (mean difference: 2.69% (95% CI: 2.23%, 3.14%), which confirmed the EPA bioavailability. Conclusion: Oral n−3 PUFAs appear to abrogate photoimmunosuppression in human skin, providing additional support for their chemopreventive role; verification of study findings is required.

No description available.

Eggs enriched with omega-3 polyunsaturated fatty acids (PUFA), particularly the longer chain PUFA (LCPUFA, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)) can boost human consumption of these fatty acids implicated in human health. Alpha-linolenic acid (ALA) from plant seeds/oils, primarily serve as the source of omega-3 PUFA for hens, however, the scarcity of ALA-rich plants and the limited conversion of ALA to LCPUFA are challenges for egg enrichment. Two major experiments were conducted to determine potential factors regulating egg enrichment of omega-3 LCPUFA based on detailed assessment of PUFA profiles in different lipid pools of hen tissues. In experiment 1, supplementation of graded levels of hempseed products, provided ~ 0.1 to 1.3% of ALA in the diets. Experiment 2, investigated dietary supplementation of flaxseed oil (ALA-rich) and algal DHA (preformed LCPUFA), each providing similar graded levels of total omega-3 PUFA. Both ALA-containing models demonstrated a plateau in DHA enrichment of eggs at higher ALA intakes. ALA-containing diets led to high concentrations of ALA in the triacylglycerol (TAG) fraction of eggs and plasma, and the adipose tissue of flaxseed oil-fed hens. In total phospholipid (PL), particularly the phosphatidylethanolamine (PE), the levels of EPA and ALA in the yolk were linearly associated with those in the liver. In all tissues, DHA dominated the PE pool, exhibiting a plateau with a strong inverse correlation to the ratio of ALA to EPA in the liver, suggesting limited ALA availability for egg DHA enrichment. The use of algal DHA should therefore permit further accumulation of DHA in the total PL and TAG fractions of yolk. However, enrichment via preformed DHA (at 3.36% algal product) was also limited by hepatic PL resulting in more DHA and EPA being shunted to the adipose TAG, concurrent with elevated hepatic acyl-CoA synthetase (ACSL1) expression. As a function of total omega-3 PUFA intakes (regardless of source), similar levels of stearidonic acid (SDA) and particularly EPA accumulated in liver PE. Therefore, hepatic PL regulation, possibly aimed at maintaining EPA level, may potentially be limiting the amount of ALA accumulation in the same pool, hence limiting the endogenous synthesis of DHA and subsequent enrichment in eggs. / February 2017

Endocannabinoids are endogenous lipid mediators involved in various biological processes, and have immunomodulatory and anti-inflammatory activities. Anandamide (arachidonoyl ethanolamine, AEA) and 2-arachidonoyl glycerol (2-AG) are the main representatives of this group. The endocannabinoid receptors CB1 and CB2 with AEA have been found in human HaCaT keratinocytes and fibroblasts, but the metabolic pathway leading to endocannabinoid production in the skin has not been fully elucidated. This study aimed to investigate the profile of endocannabinoids and their main metabolizing enzymes in human skin cells and assess whether omega-3 polyunsaturated fatty acids (n-3 PUFA) altered these profiles. In addition, an investigation was carried out to check whether UV radiation could stimulate the production of endocannabinoids and N-acylethanolamines (NAE) in human skin cells. For this purpose HaCaT keratinocytes and 46RB.1N fibroblast cells were treated with 10 and 50µM of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) or oleic acid (OA) in the presence or absence of UVR (15mJ/cm2). Data suggest that n-3 PUFA may both directly (by up-regulating NAPE-PLD levels) and indirectly (by decreasing FAAH levels) increased endocannabinoid and NAE levels in HaCaT keratinocytes and 46BR.IN fibroblasts. DHA treatment significantly decreased COX-2 expression in the absence of UVR and inhibited UVR-induced COX-2 overexpression in 46BR.IN fibroblasts. In contrast, DHA appeared to induce COX-2 up-regulation in the absence of UVR and did not prevent UVR induced COX-2 up-regulation in HaCaT keratinocytes. EPA appeared to induce COX-2 down-regulation in the absence of UVR and did not prevent UVR induced COX-2 up-regulation in both HaCaT keratinocytes and 46BR.IN fibroblasts. UVR did not have any significant effect on endocannabinoid and NAE biosynthesis. However, UVR induced endocannabinoid production in some experiments of this study. A clinical study was carried on 16 volunteers from two different ethnic groups and two different skin types. The purpose was to assess the effect of UVR on the serum endocannabinoids and NAE, therefore, the volunteers were subjected to multiple doses (1.3, SED/ 6 min) of UVR for 6 weeks. Data showed that UVR did not have major effect on human serum NAE in both skin phototypes II and V but increased 2-AG in human serum in both skin types but the more pronounced effect was evident in skin phototypes V rather than in skin phototypes II. Human serum docosahxaenoylethanolamide levels were found to be higher in White Caucasians group (skin phototypes II). Based on these it can be concluded that n-3 PUFA and UVR alter the endocannabinoids and NAE profile in HaCaT keratinocytes and 46BR.IN fibroblasts. In addition, results of the clinical study indicated that UVR has no major effects on serum endocannabinoids or NAE therefore, further studies are required to address this question in vivo.