Dietary docosahexaenoic and eicosapentaenoic acid: emerging mediators of inflammation

Nutrient composition of different energy-restricted diets determines plasma endocannabinoid profiles and adipose tissue DAGL-α expression; a 12-week randomized controlled trial in subjects with abdominal obesity

The endocannabinoid system (ECS) is dysregulated during obesity and metabolic disorders. Weight loss favours the re-establishment of ECS homeostatic conditions, but also the fatty acid composition of the diet can modulate endocannabinoid profiles. However, the combined impact of nutrient quality and energy restriction on the ECS remains unclear. In this 12 weeks randomized controlled trial, men and women (40-70 years) with obesity (BMI: 31.3 ± 3.5 kg/ m2) followed either a low nutrient quality 25% energy-restricted (ER) diet (n=39) high in saturated fats and fructose, or a high nutrient quality ER diet (n=34) amongst others enriched in n-3 polyunsaturated fatty acids (PUFAs) or kept their habitual diet (controls). Profiles of plasma- and adipose N-acylethanolamines and mono-acyl glycerol esters were quantified using LC-MS/MS. Gene expression of ECS-related enzymes and receptors was determined in adipose tissue. Measurements were performed under fasting conditions before and after 12 weeks. Our results showed that plasma level of the DHA-derived compound docosahexaenoylethanolamide (DHEA) was decreased in the low nutrient quality ER diet (P<0.001) compared with the high nutrient quality ER diet, whereas anandamide (AEA) and arachidonoylglycerol (2-AG) levels were unaltered. However, adipose tissue gene expression of the 2-AG synthesizing enzyme diacylglycerol lipase alpha (DAGL-α) was increased following the low nutrient quality ER diet (P<.009) and differed upon intervention with both other diets. Concluding, nutrient quality of the diet affects N-acylethanolamine profiles and gene expression of ECS-related enzymes and receptors even under conditions of high energy restriction in abdominally obese humans. ClinicalTrials.gov NCT02194504.

Dysregulation of cellular membrane homeostasis as a crucial modulator of cancer risk

Cellular membranes serve as an epicentre combining extracellular and cytosolic components with membranous effectors, which together support numerous fundamental cellular signalling pathways that mediate biological responses. To execute their functions, membrane proteins, lipids and carbohydrates arrange, in a highly coordinated manner, into well-defined assemblies displaying diverse biological and biophysical characteristics that modulate several signalling events. The loss of membrane homeostasis can trigger oncogenic signalling. More recently, it has been documented that select membrane active dietaries (MADs) can reshape biological membranes and subsequently decrease cancer risk. In this review, we emphasize the significance of membrane domain structure, organization and their signalling functionalities as well as how loss of membrane homeostasis can steer aberrant signalling. Moreover, we describe in detail the complexities associated with the examination of these membrane domains and their association with cancer. Finally, we summarize the current literature on MADs and their effects on cellular membranes, including various mechanisms of dietary chemoprevention/interception and the functional links between nutritional bioactives, membrane homeostasis and cancer biology.

Effects of omega-3 fatty acid supplementation on nutritional status and inflammatory response in patients with stage II-III NSCLC undergoing postoperative chemotherapy: a double-blind randomized controlled trial

Background

The primary objective of this study was to investigate the effects of oral omega-3 fatty acids in lowering the risk of malnutrition and improving the inflammatory response in patients with stage II-III lung cancer receiving postoperative chemotherapy.

Methods

One hundred and three lung cancer patients identified as being at risk for malnutrition according to the 2002 nutritional risk screening criteria were randomized into either the omega-3 fatty acid supplementation group or the placebo group during postoperative chemotherapy. Data on anthropometric parameters, laboratory nutritional indicators, and inflammatory markers were collected, and changes and differences between the two groups were compared and analyzed.

Results

Sixty three patients were included in the final analysis. The baseline information of the two groups of patients was comparable (p > 0.05). After 12 weeks, patients in the treatment group exhibited significantly higher levels of hemoglobin (11.26 ± 1.25 vs.10.60 ± 0.94, p = 0.021) and serum albumin (45.38 ± 5.06 vs.42.66 ± 5.06, p = 0.036) compared with those in the placebo group. Meanwhile, the levels of inflammatory factors C-reactive protein (2.16 ± 1.06 vs. 4.11 ± 1.72, p < 0.001), interleukin-1 (6.61 ± 2.19 vs.10.85 ± 3.61, p < 0.001), interleukin-6 (2.48 ± 1.20 vs. 4.53 ± 0.98, p < 0.001), interleukin-8 (9.26 ± 2.69 vs. 39.01 ± 6.53, p < 0.001), and tumor necrosis factor-α (1.88 ± 0.60 vs. 4.07 ± 0.97, p < 0.001) were significantly decreased in the treatment group. In contrast, differences in weight, BMI, upper arm circumference, triceps skinfold thickness, triglycerides, cholesterol, and IFN-γ between the two groups were not statistically significant (p > 0.05). Finally, in the treatment group, the levels of hemoglobin (10.89 ± 1.15 vs. 11.82 ± 1.21, p = 0.042), triglyceride (0.92 ± 0.29 vs. 1.03 ± 0.22, p = 0.043), and cholesterol (3.56 ± 0.82 vs. 4.23 ± 0.88, p = 0.045) were higher in stage II patients after the intervention compared with stage III patients.

Conclusion

Supplementation with omega-3 fatty acids improved nutritional status and reduced chronic inflammatory responses in patients with stage II-III non-small cell lung cancer undergoing postoperative chemotherapy.

Clinical Trial Registration

AEA RCT Registry, identifier AEARCTR-0007165.

The effect of omega-3 fatty acids supplementation on inflammatory biomarkers in subjects with migraine: a randomized, double-blind, placebo-controlled trial

OBJECTIVE

Imbalances in immune regulation are important features of migraine pathophysiology. In line with this, the current study investigated the efficacy of omega-3 fatty acids supplementation on inflammatory and anti-inflammatory markers in patients with migraines.

MATERIALS AND METHODS

This randomized, double-blind, placebo-controlled trial consisted of 40 patients that were prone to experiencing episodic migraines. For two months, participants were randomized into one group that received omega-3 supplementation (n= 20), 600 mg of EPA and 300 mg of DHA, twice daily) or another group that received a placebo (n= 20). Transforming growth factor β (TGF-β), interleukin (IL)-4, interferon-gamma (IFN-γ), and interleukin (IL)-17 serum levels were assessed using enzyme-linked immunosorbent assay methods at baseline and following the intervention. The current study was registered on ClinicalTrials.gov with the registration number NCT02532023.

RESULTS

After two months of intervention, the administration of omega-3 fatty acids resulted in a significant rise in the concentrations of anti-inflammatory cytokine IL-4 (p=0.010) as well as a significant reduction in concentrations of pro-inflammatory cytokine IFN-γ (p=0.001) compared with the placebo. However, no significant changes were observed in serum TGF-β and IL-17 levels.

DISCUSSION

Our findings indicated consumption of omega-3 fatty acids may have a potentially beneficial response on the inflammatory immune response in patients with migraines. Larger trials are needed to corroborate these findings.

Exploring the role of polyunsaturated fatty acid ratios in modulating neuroinflammation in LPS-induced microglia: A comprehensive in vitro analysis

The study investigated the effect of different omega (ω)- 3 and omega (ω)- 6 polyunsaturated fatty acid (PUFA) ratios on cytokine secretion, cell viability, and microglial cell shape in lipopolysaccharide (LPS)-induced microglia. The addition of PUFAs at different ratios, especially ω-3 and ratios of 7/1 and 2/1 ω-6/ω-3, resulted in a significant increase in the ameboid form of microglial cells, as well as more branching of their distal branches. Microglial cells were treated with varying ratios of PUFAs, and their cytokine secretion was measured. The results showed that all PUFA ratios had lower tumor necrosis factor (TNF)-α secretion than the control group, higher interleukin (IL)- 4 secretion in the ω-6 group, and less IL-10 secretion most down IL-6 secretion in the 7/1 ratio group. The study suggests that determining the appropriate ω-6/ω-3 consumption ratio, especially the 7/1 and 2/1 ratios, may help manage neuroinflammation, develop dietary models in immune-mediated neurodegenerative diseases, and open up new treatment possibilities.

A high ratio of linoleic acid (n-6 PUFA) to alpha-linolenic acid (n-3 PUFA) adversely affects early stage of human neuronal differentiation and electrophysiological activity of glutamatergic neurons in vitro

Introduction: There is a growing interest in the possibility of dietary supplementation with polyunsaturated fatty acids (PUFAs) for treatment and prevention of neurodevelopmental and neuropsychiatric disorders. Studies have suggested that of the two important classes of polyunsaturated fatty acids, omega-6 (n-6) and omega-3 (n-3), n-3 polyunsaturated fatty acids support brain development and function, and when used as a dietary supplement may have beneficial effects for maintenance of a healthy brain. However, to date epidemiological studies and clinical trials on children and adults have been inconclusive regarding treatment length, dosage and use of specific n-3 polyunsaturated fatty acids. The aim of this study is to generate a simplified in vitro cell-based model system to test how different n-6 to n-3 polyunsaturated fatty acids ratios affect human-derived neurons activity as a cellular correlate for brain function and to probe the mechanism of their action. Methods: All experiments were performed by use of human induced pluripotent stem cells (iPSCs). In this study, we examined the effect of different ratios of linoleic acid (n-6) to alpha-linolenic acid in cell growth medium on induced pluripotent stem cell proliferation, generation of neuronal precursors and electrophysiology of cortical glutamatergic neurons by multielectrode array (MEA) analysis. Results: This study shows that at a n-6:n-3 ratio of 5:1 polyunsaturated fatty acids induce stem cell proliferation, generating a large increase in number of cells after 72 h treatment; suppress generation of neuronal progenitor cells, as measured by decreased expression of FOXG1 and Nestin in neuronal precursor cells (NPC) after 20 days of development; and disrupt neuronal activity in vitro, increasing spontaneous neuronal firing, reducing synchronized bursting receptor subunits. We observed no significant differences for neuronal precursor cells treated with ratios 1:3 and 3:1, in comparison to 1:1 control ratio, but higher ratios of n-6 to n-3 polyunsaturated fatty acids adversely affect early stages of neuronal differentiation. Moreover, a 5:1 ratio in cortical glutamatergic neurons induce expression of GABA receptors which may explain the observed abnormal electrophysiological activity.

Effects of topical docosahexaenoic acid on postoperative fibrosis in an animal model of glaucoma filtration surgery

PURPOSE

The aim of this study was to evaluate docosahexaenoic acid (DHA) as a potential antifibrotic agent after glaucoma filtration surgery (GFS) in rats.

METHODS

A total of 36 10-week-old Brown Norway rats underwent GFS. Animals were equally divided into three groups: a control group, a DHA group and a mitomycin C (MMC) group. Intraocular pressure (IOP) was measured using a dynamic rebound tonometer, and a photograph of the surgical site was taken on days 1, 3, 7, 10, 14 and 17. The incorporation of DHA into fibroblasts was evaluated by gas chromatography. The expression of alfa-smooth muscle actin (α-SMA) and Smad proteins was assessed by Western blotting.

RESULTS

IOP decreased after surgery in animals from the three groups on day 1 after surgery. Over time, IOP remained lower in the DHA and MMC groups than in the control group (median [interquartile range] 8.0 [7.0-8.0] and 8.0 [7.3-8.0] mmHg vs. 9.0 [8.0-9.0] mmHg, respectively; p < 0.001). Bleb area in the DHA and MMC groups remained larger than that of the control group from day 7 to day 14 (3.9 [2.9-5.2] and 3.5 [2.3-4.4] mm² vs. 2.3 [2.0-2.8] mm² , respectively; p = 0.0021). We did not observe any change in DHA concentrations in the fibroblasts of the DHA group compared with the other groups.

CONCLUSION

The impact of DHA on IOP and bleb area was similar to that of MMC. The mechanisms of action of DHA in rat eye fibroblasts deserve further investigation.

The association between circulating docosahexaenoic acid and lung cancer: A Mendelian randomization study

BACKGROUND

Lung cancer is a malignant tumor with a high incidence, it is vital to identify modifiable and avoidable risk factors for primary prevention, which can significantly lower the risk of cancer by preventing exposure to hazards and altering risky behavior. Some observational studies suggest that an increase in docosahexaenoic acid (DHA) consumption can reduce lung cancer risk. However, interpretation of these observational findings is difficult due to residual confounding or reverse causality. To evaluate the link between DHA and lung cancer, we have undertaken this analysis to examine the causal association between DHA and the risk of lung cancer using a two-sample Mendelian randomization (MR) framework.

METHODS

We performed a two-sample MR analysis to evaluate the causal effect of plasma DHA levels on lung cancer risk. For the exposure data, we extracted genetic variants as instrumental variables (IVs) that are strongly associated with DHA from a large-scale genome-wide association study (GWAS). We obtained the corresponding effect estimates for IVs on the risk of lung cancer with 11,348 cases and 15,861 controls. Finally, we applied Mendelian randomization analysis to obtain preliminary MR results and performed sensitivity analyses to verify the robustness of our results.

RESULTS

According to the primary MR estimates and further sensitivity analyses, a higher serum DHA level was associated with a higher risk of lung cancer [OR = 1.159, 95% CI (1.04-1.30), P = 0.01]. For lung adenocarcinoma, the results also showed a close correlation between the DHA level and lung adenocarcinoma [OR = 1.277, 95% CI (1.09-1.50), P = 0.003], but it was not statistically significant for squamous cell carcinoma [OR = 1.071, 95% CI (0.89-1.29), P = 0.467].

CONCLUSIONS

Our study revealed that plasma DHA is positively associated with the risk of lung cancer overall, especially for lung adenocarcinoma. This study provides new information to develop dietary guidelines for primary lung cancer prevention.

Changes in lipid and fatty acid contents of gonad during the reproductive cycle of the Mediterranean swordfish Xiphias gladius

Swordfish Xiphias gladius is a large pelagic fish distributed worldwide and exploited for human consumption, however there is limited knowledge about its reproductive biology, especially regarding lipid dynamic in gonads. In teleost fish, reproductive success and offspring survival are associated to lipid availability for gamete synthesis. This study investigated the lipid composition, including lipid classes and fatty acids (FA) of cell membrane and reserve lipids (i.e., polar and neutral lipids, respectively; PL and NL), along female and male gonad development of a swordfish population from waters surrounding Corsica Island in the Mediterranean Sea. Overall, swordfish gonads contained <2% wet weight of total lipids, with testes and ovaries having similar fat content. Lipid classes and FA concentrations remained unchanged during testes maturation. However, concentrations of phosphatidyl choline (PL), triacylglycerol (NL), and some FA (16:0, 18:1n-9, and 22:6n-3) followed an "inverted U-shaped" relationship with the ovarian maturation. In both PL and NL, 22:6n-3 was the main polyunsaturated FA (>20% of total FA), while 20:5n-3 and 20:4n-6 were minor (3-6% of total FA) and varied little with maturation. 22:6n-3 and 18:1n-9 were selectively allocated to the ovarian maturation (increased in concentration and in proportion with maturation) until spawning. Finally, swordfish gonads might represent a good food source for humans given that 150 g of swordfish ovaries can cover the daily requirements in omega-3 for humans, but research on pollutants should also be conducted to evaluate their implications on the reproduction output of this species, and on the safety of swordfish gonads for human consumption.

Supplemental or dietary intake of omega-3 fatty acids for the treatment of periodontitis: A meta-analysis

AIM

To evaluate the intervention effect of omega-3 fatty acids on changes in periodontal parameters.

MATERIALS AND METHODS

This meta-analysis included studies published in English language between 2010 and 2020, which were extracted from the Cochrane Library, EMBASE, and PubMed databases. The effects of omega-3 fatty acid intervention were investigated using the amount of omega-3 intake, periodontal pocket depth (PPD), clinical attachment loss (CAL), and bleeding on probing (BOP). The random-effects model was generated for data analysis. To obtain robustness of the model, sensitivity analysis was implemented. Subgroup analyses were performed based on the intervention period for each parameter.

RESULTS

All 13 studies included in the meta-analysis were interventional, randomized controlled trials. Two studies implemented omega-3 fatty acid-rich diets, while 11 studies used supplements. Risk of bias was low, and publication bias was not shown. Meta-analysis showed a statistically significant PPD reduction (standardized mean difference [SMD] = -0.81, absolute mean difference [MD] = -0.44 mm), CAL gain (SMD = -0.77, MD = -0.51 mm), and BOP reduction (SMD = -0.65, MD = -9.45%) for the omega-3 fatty acid intervention overall.

CONCLUSION

This study suggests that supplemental or dietary intake of omega-3 fatty acids for the treatment of periodontitis may have a positive impact on the disease.

Effect of oridonin on oxylipins in the livers of mice with acute liver injury induced by D-galactosamine and lipopolysaccharide

BACKGROUND AND PURPOSE

Oridonin (Ori) has been shown to protect against acute liver injury (ALI) induced by D-galactosamine (D-GalN) and lipopolysaccharide (LPS). Oxylipins are oxidation products of polyunsaturated fatty acids (PUFAs) and are key proinflammatory mediators. This study aimed to investigate the changes in oxylipins in the livers of mice with D-GalN/LPS-induced ALI and the effects of Ori on these changes.

RESULTS

54 oxylipins in liver tissues were identified and qualitatively and quantitatively analyzed by ultra-performance liquid chromatography-electrospray ionization triple quadrupole mass spectrometry (UPLC-QTRAP/MS/MS). The levels of 12-HETE, 12-HEPE, 14(S)-HDHA, PGE2, dihomo-γ-linolenic acid and 13-HOTrE in the liver were significantly increased in the D-GalN/LPS-induced ALI group compared with the control group, and the levels of EPA and 7-HDHA were significantly decreased. However, pretreatment with Ori dramatically decreased the levels of 12-HETE, 12-HEPE, 14(S)-HDHA, PGE2 and 13-HOTrE compared with those of the ALI group and induced 7-HDHA and 15-oxoETE. Moreover, Ori reduced the protein levels of COX-1, COX-2, ALOX5, ALOX12 and ALOX15 induced by D-GalN/LPS, indicating that Ori altered oxylipins through the COX and LOX pathways.

CONCLUSIONS

These results suggest that the protective effect of Ori on ALI is partly mediated by affecting the oxylipin pathway.

Diverse Krill Lipid Fractions Differentially Reduce LPS-Induced Inflammatory Markers in RAW264.7 Macrophages In Vitro

Antarctic krill oil is an emerging marine lipid and expected to be a potential functional food due to its diverse nutrients, such as eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), phospholipids, astaxanthin and tocopherols. Although krill oil has been previously proved to have anti-inflammatory activity, there is little information about the relationship between its chemical compositions and anti-inflammatory activity. In this study, the RAW264.7 macrophages model was used to elucidate and compare the anti-inflammatory potential of different krill lipid fractions: KLF-A, KLF-H and KLF-E, which have increasing phospholipids, EPA and DHA contents but decreasing astaxanthin and tocopherols levels. Results showed that all the krill lipid fractions alleviated the inflammatory reaction by inhibition of production of nitric oxide (NO), release of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-6 and gene expression of proinflammatory mediators including TNF-α, IL-1β, IL-6, cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS). In addition, KLF-E with the highest phospholipids, EPA and DHA contents showed the strongest inhibition effect on the LPS-induced proinflammatory mediator release and their gene expressions. The results would be helpful to provide powerful insights into the underlying anti-inflammatory mechanism of krill lipid and guiding the production of krill oil products with tailor-made anti-inflammatory activity.

Sex Differences in Otolaryngology: Focus on the Emerging Role of Estrogens in Inflammatory and Pro-Resolving Responses

Otolaryngology (also known as ear, nose, and throat (ENT)) diseases can be significantly affected by the level of sex hormones, which indicates that sex differences affect the manifestation, pathophysiology, and outcomes of these diseases. Recently, increasing evidence has suggested that proinflammatory responses in ENT diseases are linked to the level of sex hormones. The sex hormone receptors are present on a wide variety of immune cells; therefore, it is evident that they play crucial roles in regulating the immune system and hence affect the disease progression of ENT diseases. In this review, we focus on how sex hormones, particularly estrogens, regulate ENT diseases, such as chronic rhinosinusitis, vocal fold polyps, thyroid cancer, Sjögren’s syndrome, and head and neck cancers, from the perspectives of inflammatory responses and specialized proresolving mediator-driven resolution. This paper aims to clarify why considering sex differences in the field of basic and medical research on otolaryngology is a key component to successful therapy for both males and females in the future.

Modulation of behavioral and neurochemical responses of adult zebrafish by fluoxetine, eicosapentaenoic acid and lipopolysaccharide in the prolonged chronic unpredictable stress model

Long-term recurrent stress is a common cause of neuropsychiatric disorders. Animal models are widely used to study the pathogenesis of stress-related psychiatric disorders. The zebrafish (Danio rerio) is emerging as a powerful tool to study chronic stress and its mechanisms. Here, we developed a prolonged 11-week chronic unpredictable stress (PCUS) model in zebrafish to more fully mimic chronic stress in human populations. We also examined behavioral and neurochemical alterations in zebrafish, and attempted to modulate these states by 3-week treatment with an antidepressant fluoxetine, a neuroprotective omega-3 polyunsaturated fatty acid eicosapentaenoic acid (EPA), a pro-inflammatory endotoxin lipopolysaccharide (LPS), and their combinations. Overall, PCUS induced severe anxiety and elevated norepinephrine levels, whereas fluoxetine (alone or combined with other agents) corrected most of these behavioral deficits. While EPA and LPS alone had little effects on the zebrafish PCUS-induced anxiety behavior, both fluoxetine (alone or in combination) and EPA restored norepinephrine levels, whereas LPS + EPA increased dopamine levels. As these data support the validity of PCUS as an effective tool to study stress-related pathologies in zebrafish, further research is needed into the ability of various conventional and novel treatments to modulate behavioral and neurochemical biomarkers of chronic stress in this model organism.

Peroxisomal ABC Transporters: An Update

ATP-binding cassette (ABC) transporters constitute one of the largest superfamilies of conserved proteins from bacteria to mammals. In humans, three members of this family are expressed in the peroxisomal membrane and belong to the subfamily D: ABCD1 (ALDP), ABCD2 (ALDRP), and ABCD3 (PMP70). These half-transporters must dimerize to form a functional transporter, but they are thought to exist primarily as tetramers. They possess overlapping but specific substrate specificity, allowing the transport of various lipids into the peroxisomal matrix. The defects of ABCD1 and ABCD3 are responsible for two genetic disorders called X-linked adrenoleukodystrophy and congenital bile acid synthesis defect 5, respectively. In addition to their role in peroxisome metabolism, it has recently been proposed that peroxisomal ABC transporters participate in cell signaling and cell control, particularly in cancer. This review presents an overview of the knowledge on the structure, function, and mechanisms involving these proteins and their link to pathologies. We summarize the different in vitro and in vivo models existing across the species to study peroxisomal ABC transporters and the consequences of their defects. Finally, an overview of the known and possible interactome involving these proteins, which reveal putative and unexpected new functions, is shown and discussed.

Inositol hexaphosphate modulates the behavior of macrophages through alteration of gene expression involved in pathways of pro- and anti-inflammatory responses, and resolution of inflammation pathways

Inositol hexaphosphate (IP6) is a dietary compound commonly obtained from corn, rice, etc. Although we may consume significant amount of IP6 daily, it is unclear whether this diet will impact macrophages' fate and function. Therefore, we characterized the underlying relationship between IP6 and macrophage polarization in this study. We specifically examined the signature gene expression profiles associated with pro- and anti-inflammatory responses, and resolution of inflammation pathways in macrophages under the influence of IP6. Interestingly, our data suggested that IP6 polarizes bone marrow-derived macrophages (BMDM) into an M2a-like subtype. Our results also demonstrated that IP6 reduces lipopolysaccharide-induced apoptosis and pro-inflammatory responses in macrophages. In contrast, the expression levels of genes related to anti-inflammatory responses and resolution of inflammation pathways are upregulated. Our findings collectively demonstrated that IP6 has profound modulation effects on macrophages, which warrant further research on the therapeutic benefits of IP6 for inflammatory diseases.

Invited review: Milk fat globule membrane-A possible panacea for neurodevelopment, infections, cardiometabolic diseases, and frailty

Milk is an evolutionary benefit for humans. For infants, it offers optimal nutrients for normal growth, neural development, and protection from harmful microbes. Humans are the only mammals who drink milk throughout their life. Lipids in colostrum originate mostly from milk fat globule membrane (MFGM) droplets extruded from the mammary gland. The MFGM gained much interest as a potential nutraceutical, due to their high phospholipid (PL), ganglioside (GD), and protein contents. In this review, we focused on health effects of MFGM ingredients and dairy food across the life span, especially on neurodevelopment, cardiometabolic health, and frailty in older adults. The MFGM supplements to infants and children reduced gastrointestinal and respiratory tract infections and improved neurodevelopment due to the higher content of protein, PL, and GD in MFGM. The MFGM formulas containing PL and GD improved brain myelination and fastened nerve conduction speed, resulting in improved behavioral developments. Administration of MFGM-rich ingredients improved insulin sensitivity and decreased inflammatory markers, LDL-cholesterol, and triglycerides by lowering intestinal absorption of cholesterol and increasing its fecal excretion. The MFGM supplements, together with exercise, improved ambulatory activities, leg muscle mass, and muscle fiber velocity in older adults. There are great variations in the composition of lipids and proteins in MFGM products, which make comparisons of the different studies impossible. In addition, investigations of the individual MFGM components are required to evaluate their specific effects and molecular mechanisms. Although we are currently only beginning to understand the possible health effects of MFGM products, the current MFGM supplementation trials as presented in this review have shown significant clinical health benefits across the human life span, which are worth further investigation.

A Prospective Ultrasound Study of Plasma Polychlorinated Biphenyl Concentrations and Incidence of Uterine Leiomyomata

BACKGROUND

Uterine leiomyomata, or fibroids, are hormone-dependent neoplasms of the myometrium that can cause severe gynecologic morbidity. In previous studies, incidence of these lesions has been positively associated with exposure to polychlorinated biphenyls (PCBs), a class of persistent endocrine-disrupting chemicals. However, previous studies have been retrospective in design and none has used ultrasound to reduce disease misclassification.

METHODS

The Study of Environment, Lifestyle, and Fibroids is a prospective cohort of 1,693 reproductive-aged Black women residing in Detroit, Michigan (enrolled during 2010-2012). At baseline and every 20 months for 5 years, women completed questionnaires, provided blood samples, and underwent transvaginal ultrasound to detect incident fibroids. We analyzed 754 baseline plasma samples for concentrations of 24 PCB congeners using a case-cohort study design. We used multivariable Cox proportional hazards regression to estimate hazard ratios (HRs) and 95% confidence intervals for the association between plasma PCB concentrations and ultrasound-detected fibroid incidence over a 5-year period.

RESULTS

We observed little association between PCB congener concentrations and fibroid incidence. The HR for a one-standard deviation increase in log-transformed total PCBs was 0.94 (95% CI = 0.78, 1.1). The PCB congener with the largest effect estimate was PCB 187 (HR for a one-standard deviation increase in log-transformed exposure = 0.88, 95% CI = 0.73, 1.1). Associations did not seem to vary strongly across PCB groupings based on hormonal activity.

CONCLUSIONS

In this cohort of reproductive-aged Black women, plasma PCB concentrations typical of the contemporary general population were not appreciably associated with higher risk of fibroids.

Lipid Composition, Digestion, and Absorption Differences among Neonatal Feeding Strategies: Potential Implications for Intestinal Inflammation in Preterm Infants

Necrotizing enterocolitis (NEC) is a significant cause of morbidity and mortality in the neonatal population. Formula feeding is among the many risk factors for developing the condition, a practice often required in the cohort most often afflicted with NEC, preterm infants. While the virtues of many bioactive components of breast milk have been extolled, the ability to digest and assimilate the nutritional components of breast milk is often overlooked. The structure of formula differs from that of breast milk, both in lipid composition and chemical configuration. In addition, formula lacks a critical digestive enzyme produced by the mammary gland, bile salt-stimulated lipase (BSSL). The gastrointestinal system of premature infants is often incapable of secreting sufficient pancreatic enzymes for fat digestion, and pasteurization of donor milk (DM) has been shown to inactivate BSSL, among other important compounds. Incompletely digested lipids may oxidize and accumulate in the distal gut. These lipid fragments are thought to induce intestinal inflammation in the neonate, potentially hastening the development of diseases such as NEC. In this review, differences in breast milk, pasteurized DM, and formula lipids are highlighted, with a focus on the ability of those lipids to be digested and subsequently absorbed by neonates, especially those born prematurely and at risk for NEC.

Peroxisomes of the Brain: Distribution, Functions, and Associated Diseases

Peroxisomes are versatile cell organelles that exhibit a repertoire of organism and cell-type dependent functions. The presence of oxidases and antioxidant enzymes is a characteristic feature of these organelles. The role of peroxisomes in various cell types in human health and disease is under investigation. Defects in the biogenesis of the organelle and its function lead to severe debilitating disorders. In this manuscript, we discuss the distribution and functions of peroxisomes in the nervous system and especially in the brain cells. The important peroxisomal functions in these cells and their role in the pathology of associated disorders such as neurodegeneration are highlighted in recent studies. Although the cause of the pathogenesis of these disorders is still not clearly understood, emerging evidence supports a crucial role of peroxisomes. In this review, we discuss research highlighting the role of peroxisomes in brain development and its function. We also provide an overview of the major findings in recent years that highlight the role of peroxisome dysfunction in various associated diseases.

Algal Oil Rich in n-3 PUFA Alleviates DSS-Induced Colitis via Regulation of Gut Microbiota and Restoration of Intestinal Barrier

Algal oil is rich in docosahexaenoic acid (DHA) and has various health benefits against human metabolic disorders and disease. This study aimed to investigate the effects of DHA algal oil on colonic inflammation and intestinal microbiota in dextran sulfate sodium (DSS)-induced colitis mice model. Male C57BL/6 mice was induced colitis by 2.5% DSS and followed by 2 weeks of treatment with algal oil (250 or 500 mg/kg/day). The colonic inflammation was assessed by colon macroscopic damage scores, and the degree of neutrophil infiltration was evaluated by measuring tissue-associated myeloperoxidase (MPO) activity in colonic mucosa. Tight junction proteins in the colonic tissue were measured by real-time PCR and western blot. Moreover, the intestinal microbiota and shot chain fatty acids (SCFAs) were estimated by bioinformatic analysis and GC, respectively. Colonic damage due to DSS treatment was significantly ameliorated by algal oil supplementation. In addition, algal oil significantly inhibited the increases of malondialdehyde (MDA) content, MPO activity, pro-inflammatory cytokines level and tight junction proteins expression in DSS-treated mice. Furthermore, supplementation of algal oil modulated the intestinal microbiota structure in DSS induced colitis mice by increasing the proportion of the unidentified_S24_7 and decreasing the relative abundance of unidentified_Ruminococcaceae, Clostridium and Roseburia. On the analysis of SCFAs, the caecal content of acetic acid, propionic acid, isobutyric acid, buturic, and the total SCFAs showed a significant increase in algal oil-administered mice. Together, these results suggested that algal oil rich in DHA inhibited the progress of DSS-induced colitis in mice by modulating the intestinal microbiota and metabolites and repairing the intestinal barrier, which may be applied in the development of therapeutics for intestinal inflammation.

Dietary Fat Intake and Risk of Uterine Leiomyomata: A Prospective Ultrasound Study

Uterine leiomyomata (UL) are associated with severe reproductive morbidity and are the primary indication for hysterectomy in the United States. A recent prospective cohort study of Black women reported positive associations between intakes of marine-sourced ω-3 fatty acids and UL risk. We examined whether intakes of dietary fat were associated with UL incidence in a 5-year prospective study of premenopausal Black women living in Detroit who underwent serial ultrasound. At baseline (2010-2012) and 20, 40, and 60 months of follow-up, participants underwent transvaginal ultrasound. Among 1,171 UL-free women at baseline, incident UL were detected in 277 women. Cox regression was used to estimate hazard ratios and 95% confidence intervals for the association of dietary fat and UL incidence. Intakes of total fat and saturated, monounsaturated, polyunsaturated, and trans-fat were not appreciably associated with UL incidence. Intake of the marine ω-3 polyunsaturated fatty acid, docosahexaenoic acid, was associated with 49% higher UL incidence (quartile 4 vs. 1: hazard ratio = 1.49, 95% confidence interval: 1.04, 2.14; P for trend = 0.01). Intakes of total marine ω-3 polyunsaturated fatty acids were similarly associated with elevated UL incidence (hazard ratio = 1.35, 95% confidence interval: 0.94, 1.93; P for trend = 0.03). It remains unclear whether the fatty acids or persistent environmental pollutants drive the association.

A review on differential effects of dietary fatty acids on weight, appetite and energy expenditure

The association between weight and chronic diseases is well defined. The quality and quantity of dietary fatty acids is an important external factor and appetite and energy expenditure, are important internal factors in determining body weight. On the other hand, dietary fatty acids composition can modulate appetite and energy metabolism, but not all fats are equal in producing metabolic responses.Given the accumulating evidence for differential effects of various dietary fatty acids, one important area of investigation is to scrutinize their roles in weight, appetite and energy expenditure modulation. There is substantial evidence to suggest that saturated fatty acids have a greater effect on appetite control, although in the long run may result in more weight gain than unsaturated fatty acids due to a weaker stimulation of energy expenditure. In contrast, mono-unsaturated fats do not have much effects on appetite control, but they can be beneficial in weight control over the long term due to stimulatory effects on energy expenditure. Interestingly, in case of poly unsaturated fats, including n-3 and n-6, their effect on increasing energy expenditure is aligned, but they act differently in controlling weight and appetite.

Impact of Arachidonic and Docosahexaenoic Acid Supplementation on Neural and Immune Development in the Young Pig

Background: Human milk contains both arachidonic acid (ARA) and docosahexaenoic acid (DHA). Supplementation of infant formula with ARA and DHA results in fatty acid (FA) profiles, neurodevelopmental outcomes, and immune responses in formula-fed infants that are more like those observed in breastfed infants. Consequently, ARA and DHA have been historically added together to infant formula. This study investigated the impact of ARA or DHA supplementation alone or in combination on tissue FA incorporation, immune responses, and neurodevelopment in the young pig.

Methods: Male pigs (N = 48 total) received one of four dietary treatments from postnatal day (PND) 2–30. Treatments targeted the following ARA/DHA levels (% of total FA): CON (0.00/0.00), ARA (0.80/0.00), DHA (0.00/0.80), and ARA+DHA (0.80/0.80). Plasma, red blood cells (RBC), and prefrontal cortex (PFC) were collected for FA analysis. Blood was collected for T cell immunophenotyping and to quantify a panel of immune outcomes. Myelin thickness in the corpus callosum was measured by transmission electron microscopy and pig movement was measured by actigraphy.

Results: There were no differences in formula intake or growth between dietary groups. DHA supplementation increased brain DHA, but decreased ARA, compared with all other groups. ARA supplementation increased brain ARA compared with all other groups but did not affect brain DHA. Combined supplementation increased brain DHA levels but did not affect brain ARA levels compared with the control. Pigs fed ARA or ARA+DHA exhibited more activity than those fed CON or DHA. Diet-dependent differences in activity suggested pigs fed ARA had the lowest percent time asleep, while those fed DHA had the highest. No differences were observed for immune or myelination outcomes.

Conclusion: Supplementation with ARA and DHA did not differentially affect immune responses, but ARA levels in RBC and PFC were reduced when DHA was provided without ARA. Supplementation of either ARA or DHA alone induced differences in time spent asleep, and ARA inclusion increased general activity. Therefore, the current data support the combined supplementation with both ARA and DHA in infant formula and raise questions regarding the safety and nutritional suitability of ARA or DHA supplementation individually.

Effects of Cerebrolysin on Hippocampal Neuronal Death After Pilocarpine-Induced Seizure

Epilepsy is one of the most common and severe brain diseases. The exact cause of epilepsy is unclear. Epilepsy often occurs following brain damage, such as traumatic brain injury (TBI) and ischemia. Cerebrolysin is a porcine brain peptide that is a unique neurotropic and neuroprotective agent. Cerebrolysin has been reported to increase neuroprotective effects after TBI, ischemia, and other CNS diseases. However, the effects of cerebrolysin on seizures are not known. Therefore, this study aimed to investigate the effects of neuropeptide cerebrolysin on neuronal death in the hippocampus after a seizure. To confirm the effects of cerebrolysin, we used a pilocarpine-induced seizure animal model. Cerebrolysin (2.5 ml/kg, i.p., once per day for 7 days) was immediately injected after a seizure induction. After 1 week, we obtained brain tissues and performed staining to histologically evaluate the potentially protective effects of cerebrolysin on seizure-induced neuronal death in the hippocampus. We found that cerebrolysin decreased hippocampal neuronal death after a seizure. In addition, an increase in brain-derived neurotrophic factor (BDNF) was confirmed through Western blot analysis to further support our hypothesis. Therefore, the present study suggests that the administration of cerebrolysin can be a useful therapeutic tool for preventing neuronal death after a seizure.

DHA from microalgae Schizochytrium spp. (Thraustochytriaceae) modifies the inflammatory response and gonadal lipid profile in domestic cats

The present study aimed to evaluate the inflammatory response, oxidative status and fatty acid deposition in reproductive tissues of cats supplemented with the dried microalgae Schizochytrium spp. (Thraustochytriaceae) as a DHA source. Thirty-seven cats (males, n 21; females, n 16; 11·5 (sd 0·5) months of age) were divided by sex into five groups. Treatment diets contained algae biomass at 4·0, 8·0, 12·0 or 16·0 g/kg replacing poultry fat (n-6 source). Cats were fed the respective diet for 62 d and neutered on day 58. Blood samples were collected at the beginning of the experiment (day 1), before neutering (day 58) and 4 d after surgery (day 62) for analysis of inflammation and oxidative markers. Acute-phase protein levels were altered (P < 0·01) in the postoperative period, without any treatment effect (P > 0·05). PGE2 concentrations after surgery were reduced linearly (R2 0·8706; P = 0·002) with microalgal inclusion. Blood platelet count was reduced (P = 0·001) after the surgery regardless treatment, but it was higher in the DHA group compared with control (P < 0·001). The DHA deposition (testicles, R2 0·846; ovaries, R2 0·869) and the n-6:n-3 ratio (testicles, R2 0·859; ovaries, R2 0·955) in gonads had a pattern which fitted a quadratic model. DHA from Schizochytrium spp. modifies PGE2 response after the surgery in cats. The physiological roles of the DHA in the reproduction of cats were not investigated, but its gonadal deposition after supplementation was observed.

Supplementation with omega-3 fatty acids potentiates oxidative stress in human airway epithelial cells exposed to ozone

BACKGROUND

Dietary intake of the omega-3 family of polyunsaturated fatty acids (ω-3 FA) is associated with anti-inflammatory effects. However, unsaturated fatty acids are susceptible to oxidation, which produces pro-inflammatory mediators. Ozone (O₃) is a tropospheric pollutant that reacts rapidly with unsaturated fatty acids to produce electrophilic and oxidative mediators of inflammation.

OBJECTIVE

Determine whether supplementation with ω-3 FA alters O₃-induced oxidative stress in human airway epithelial cells (HAEC).

METHODS

16-HBE cells expressing a genetically encoded sensor of the reduced to oxidized glutathione ratio (GSH/GSSG, E_GSH) were supplemented with saturated, monounsaturated, or ω-3 FA prior to exposure to 0, 0.08, 0.1, or 0.3 ppm O₃. Lipid peroxidation was measured in cellular lipid extracts and intact cells following O₃ exposure.

RESULTS

Relative to cells incubated with the saturated or monounsaturated fatty acids, cells supplemented with ω-3 FA containing 5 or 6 double bonds showed a marked increase in E_GSH during exposure to O₃ concentrations as low as 0.08 ppm. Consistent with this finding, the concentration of lipid hydroperoxides produced following O₃ exposure was significantly elevated in ω-3 FA supplemented cells.

DISCUSSION

Supplementation with polyunsaturated ω-3 FA potentiates oxidative responses, as indicated by E_GSH, in HAEC exposed to environmentally relevant concentrations of O₃. This effect is mediated by the increased formation of lipid hydroperoxides produced by the reaction of O₃ with polyunsaturated fatty acids. Given the inflammatory activity of lipid hydroperoxides, these findings have implications for the potential role of ω-3 FA in increasing human susceptibility to the adverse health effects of O₃ exposure.

Cardiovascular Benefits of Fish-Oil Supplementation Against Fine Particulate Air Pollution in China

BACKGROUND

Few studies have evaluated the health benefits of omega-3 fatty acid supplementation against fine particulate matter (aerodynamic diameter <2.5 μm [PM_2.5]) exposure in highly polluted areas.

OBJECTIVES

The authors sought to evaluate whether dietary fish-oil supplementation protects cardiovascular health against PM_2.5 exposure in China.

METHODS

This is a randomized, double-blinded, and placebo-controlled trial among 65 healthy college students in Shanghai, China. Participants were randomly assigned to either the placebo group or the intervention group with dietary fish-oil supplementation of 2.5 g/day from September 2017 to January 2018, and received 4 rounds of health examinations in the last 2 months of treatments. Fixed-site PM_2.5 concentrations on campus were measured in real time. The authors measured blood pressure and 18 biomarkers of systematic inflammation, coagulation, endothelial function, oxidative stress, antioxidant activity, cardiometabolism, and neuroendocrine stress response. Acute effects of PM_2.5 on these outcomes were evaluated within each group using linear mixed-effect models.

RESULTS

The average PM_2.5 level was 38 μg/m³ during the study period. Compared with the placebo group, the fish-oil group showed relatively stable levels of most biomarkers in response to changes in PM_2.5 exposure. Between-group differences associated with PM_2.5 exposure varied by biomarkers and by lags of exposure. The authors observed beneficial effects of fish-oil supplementation on 5 biomarkers of blood inflammation, coagulation, endothelial function, oxidative stress, and neuroendocrine stress response in the fish-oil group at a false discovery rate of <0.05.

CONCLUSIONS

This trial shows that omega-3 fatty acid supplementation is associated with short-term subclinical cardiovascular benefits against PM_2.5 exposure among healthy young adults in China. (Effect of Dietary Supplemental Fish Oil in Alleviating Health Hazards Associated With Air Pollution; NCT03255187).

Effect of Free Fatty Acids on Inflammatory Gene Expression and Hydrogen Peroxide Production by Ex Vivo Blood Mononuclear Cells

The aim of this study was to assess free fatty acids’ (FAs) ex vivo anti-/proinflammatory capabilities and their influence on inflammatory gene expression and H₂O₂ production by human peripheral blood mononuclear cells (PBMCs). Anthropometric and clinical measurements were performed in 26 participants with metabolic syndrome. Isolated PBMCs were incubated ex vivo for 2 h with several free fatty acids—palmitic, oleic, α-linolenic, γ-linolenic, arachidonic and docosahexaenoic at 50 μM, and lipopolysaccharide (LPS) alone or in combination. H₂O₂ production and IL6, NFκB, TLR2, TNFα, and COX-2 gene expressions were determined. Palmitic, γ-linolenic, and arachidonic acids showed minor effects on inflammatory gene expression, whereas oleic, α-linolenic, and docosahexaenoic acids reduced proinflammatory gene expression in LPS-stimulated PBMCs. Arachidonic and α-linolenic acids treatment enhanced LPS-stimulated H₂O₂ production by PBMCs, while palmitic, oleic, γ-linolenic, and docosahexaenoic acids did not exert significant effects. Oleic, α-linolenic, and docosahexaenoic acids induced anti-inflammatory responses in PBMCs. Arachidonic and α-linolenic acids enhanced the oxidative status of LPS-stimulated PBMCs. In conclusion, PBMC ex vivo assays are useful to assess the anti-/proinflammatory and redox-modulatory effects of fatty acids or other food bioactive compounds.

Effects of dietary supplementation with a microalga (Schizochytrium sp.) on the hemato-immunological, and intestinal histological parameters and gut microbiota of Nile tilapia in net cages

Nutritional improvements in intensive aquaculture production systems is necessary for the reduction of stress, maximum utilization of nutritional components, and expression of the genetic potential of fish. The objective of this study was to evaluate the hemato-immunological, and histological parameters and gut microbiota of Nile tilapia fed with the microalga Schizochytrium sp. Males of Nile tilapia were distributed among eight net cages (6 m³), and fed for 105 days with two diets: control (CON), without Schizochytrium sp., and supplemented (SUP), with 1.2% Schizochytrium sp. in the diet. The final weight, mortality, hematocrit, total erythrocyte count (RBC), hemoglobin, hematimetric indices, white blood cell count (WBC), total protein, and serum lysozyme were measured. Alterations in intestinal morphology were evaluated. The gut microbiota was evaluated with next-generation sequencing. No significant differences (p>0.05) were found in the final weight and mortality between diets. Regarding the hematological parameters, a difference (p<0.05) was detected only in RBC, with there being lower values in the SUP, although this group also showed a tendency toward having an increased mean corpuscular hemoglobin level. There were no differences (p>0.05) in total protein and serum lysozyme concentrations or in WBCs between diets, except for lymphocytes, which presented lower values (p<0.05) in the SUP, suggesting immunomodulation by the polyunsaturated fatty acids present in the microalga. There was no difference (p>0.05) in the intestinal morphology between diets. Metagenomic data indicated greater richness (represented by the Chao index) and a higher abundance of the bacterial phylum Firmicutes in the gut microbiota of the tilapia fed with the SUP diet, demonstrating that the digestion and use of the components of the microalga could influence the microbial community. The results indicated that the microalga had modulatory effects on blood cells and the intestinal microbiota, without affecting the structure and integrity of the intestinal villi.

Resistance exercise with anti-inflammatory foods attenuates skeletal muscle atrophy induced by chronic inflammation

Chronic inflammation (CI) can contribute to muscle atrophy and sarcopenia. Resistance exercise (RE) promotes increased and/or maintenance of skeletal muscle mass, but the effects of RE in the presence of CI are unclear. In this study, we developed a novel animal model of CI-induced muscle atrophy and examined the effect of acute or chronic RE by electrical stimulation. CI was induced in young female Lewis rats by injection with peptidoglycan-polysaccharide (PG-PS). Extracellular signal-regulated kinase (ERK), p70S6 kinase (p70S6K), 4E binding protein 1 (4E-BP1), Akt, and Forkhead box O1 (FOXO1) phosphorylation levels increased in gastrocnemius (Gas) muscle from normal rats subjected to acute RE. After acute RE in CI rats, increased levels of phosphorylated ERK, p70S6K, and 4E-BP1, but not Akt or FOXO1, were observed. Chronic RE significantly increased the Gas weight in the exercised limb relative to the nontrained opposing limb in CI rats. Dietary supplementation with anti-inflammatory agents, eicosapentaenoic/docosahexaenoic acid and α-lactalbumin attenuated CI-induced muscle atrophy in the untrained Gas and could promote RE-induced inhibition of atrophy in the trained Gas. In the trained leg, significant negative correlations ( r ≤ −0.80) were seen between Gas weights and CI indices, including proinflammatory cytokines and white blood cell count. These results indicated that the anabolic effects of RE are effective for preventing CI-induced muscle atrophy but are partially attenuated by inflammatory molecules. The findings also suggested that anti-inflammatory treatment together with RE is an effective intervention for muscle atrophy induced by CI. Taken together, we conclude that systemic inflammation levels are associated with skeletal muscle protein metabolism and plasticity.

NEW & NOTEWORTHY This study developed a novel chronic inflammation (CI) model rat demonstrating that resistance exercise (RE) induced activation of protein synthesis signaling pathways and mitigated skeletal muscle atrophy. These anabolic effects were partially abrogated likely through attenuation of Akt/Forkhead box O1 axis activity. The degree of skeletal muscle atrophy was related to inflammatory responses. Dietary supplementation with anti-inflammatory agents could enhance the anabolic effect of RE. Our findings provide insight for development of countermeasures for CI-related muscle atrophy, especially secondary sarcopenia.

Microalgae Schizochytrium sp. as a source of docosahexaenoic acid (DHA): Effects on diet digestibility, oxidation and palatability and on immunity and inflammatory indices in dogs

The objective of this study was to evaluate the effects of the microalgae Schizochytrium sp., as a dietary source of docosahexaenoic acid (DHA), on diet palatability, coefficients of total tract apparent digestibility (CTTAD) of nutrients and metabolizable energy (ME), blood variables and indicators of immunity in dogs. We also evaluated oxidative stability. Two diets containing 0 and 0.4% of microalgae Schizochytrium sp. were evaluated in three experiments. On Experiment I the palatability of diets containing 0% versus 0.4% microalgae was compared. In Experiment II test diets were offered for 30 days to determine digestibility, fecal characteristics, and blood parameters. In Experiment III, the oxidative stability of diets containing microalgae versus anchovy oil was evaluated. There was a higher intake ratio of the diet containing microalgae (p < .05). The ME and CTTAD of nutrients increased (p < .05), except for ether extract after acid hydrolysis, with the inclusion of the microalgae in diet. The amount of monocytes and phagocytic granulocytes was higher (p < .05) in dogs fed 0.4% microalgae. There was greater oxidative stability for the sample containing microalgae. The addition of 0.4% microalgae presented high palatability, increased phagocytic cell numbers, and demonstrated oxidative stability superior to anchovy oil.

17-Oxo-docosahexaenoic acid induces Nrf2-mediated expression of heme oxygenase-1 in mouse skin in vivo and in cultured murine epidermal cells

Recently, growing attention has been given to new classes of bioactive lipid mediators derived from ω-3 polyunsaturated fatty acids, such as docosahexaenoic acid (DHA), especially in the context of their role as endogenous signal modulators. One such molecule is 17-oxo-DHA, generated from DHA by the action of COX2 and a dehydrogenase. The redox-sensitive transcription factor, Nrf2 plays a key role in cellular stress responses. In the present study, the effects of 17-oxo-DHA on Nrf2-mediated expression of cytoprotective enzymes were examined in mouse skin in vivo and cultured murine epidermal JB6 cells. Topical application of 17-oxo-DHA markedly elevated the nuclear localization of Nrf2 and expression of heme oxygenase-1 (HO-1) and NAD(P)H:quinone oxidoreductase-1 in hairless mouse skin. In contrast to 17-oxo-DHA, the non-electrophilic metabolic precursor 17-hydroxy-DHA was a much weaker inducer of Nrf2 activation and its target protein expression. Likewise, 17-oxo-DHA significantly enhanced nuclear translocation and transcriptional activity of Nrf2 with concomitant upregulation of HO-1 expression in cultured JB6 cells. 17-Oxo-DHA was a much stronger inducer of Nrf2-mediated antioxidant response than its parent molecule, DHA. HO-1 expression was abolished in Nrf2 knockdown JB6 cells or embryo fibroblasts from Nrf2 knock out mice. 17-Oxo-DHA also markedly reduced the level of Keap1 protein by inducing ubiquitination. Mutation of Cys151 and Cys273 in Keap1 abrogated 17-oxo-DHA-induced ubiquitination and proteasome-mediated degradation of Keap1 as well as HO-1 expression, suggesting that these cysteine residues are putative sites for 17-oxo-DHA binding. Further, Keap1 degradation stimulated by 17-oxo-DHA coincided with accumulation of the autophagy substrate, p62/SQSTM1.

Low n-6/n-3 PUFA ratio improves inflammation and myocardial ischemic reperfusion injury

This study investigated the potential effect of n-6/n-3 polyunsaturated fatty acids (PUFA) on inflammation and myocardial ischemic reperfusion injury (MIRI) in rats, together with the underlying protective mechanisms, and screen out most effective ratio of n-6/n-3 within limits. The rats with pre-infarct treatment were distributed among 5 groups according to the n-6/n-3 ratio (36:1; 1:1, 5:1, 10:1, 50:1); for the post-infarct treatment, the rats were distributed among 6 groups, including the control group (36:1) which was subjected to a sham procedure; the model group (36:1); and 4 test groups (n-6/n-3 ratio: 1:1, 5:1, 10:1, 50:1). All of the rats were fed a purple perilla seed oil and safflower oil-based fatty emulsion. The serum levels of monocyte chemoattractant protein-1 (MCP-1), interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α were determined using enzyme-linked immunosorbent assay. Staining with triphenyl tetrazolium chloride, hematoxylin and eosin, or Masson's trichrome was performed for histological examination. Cardiomyocyte apoptosis was examined by TUNEL assay. Western blotting was performed to examine the expression levels of apoptosis-related proteins and signaling pathway proteins. Our data indicate that in both the pre-infarct treatment and post-infarct treatment, low ratios of n-6/n-3 PUFAs significantly inhibited the levels of serum inflammatory factors, the infarct size of MIRI rats, number of cardiomyocytes undergoing apoptosis, and the expression levels of caspase-3, Bcl-2, and Bax in the MIRI group. Thus a low ratio of n-6/n-3 PUFAs ameliorates inflammation and myocardial ischemic reperfusion injury.

N-Eicosapentaenoyl Dopamine, A Conjugate of Dopamine and Eicosapentaenoic Acid (EPA), Exerts Anti-inflammatory Properties in Mouse and Human Macrophages

A large body of evidence suggests that dietary n-3 polyunsaturated fatty acids (PUFAs), including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), contribute to a reduced inflammatory tone thereby lowering the risk for several chronic and degenerative diseases. Different mechanisms have been proposed to explain these anti-inflammatory effects, including those involving endocannabinoids and endocannabinoid-like molecules. In this context, fatty acid amides (FAAs), conjugates of fatty acids with amines or amino acids, are an emerging class of compounds. Dopamine conjugates of DHA (N-docosahexaenoyl dopamine, DHDA) and EPA (N-eicosapentaenoyl dopamine, EPDA) have previously been shown to induce autophagy, apoptosis, and cell death in different tumor lines. Additionally, DHDA has displayed anti-inflammatory properties in vitro. Here, we tested the immune-modulatory properties of EPDA in mouse RAW 264.7 and human THP-1 macrophages stimulated with lipopolysaccharide (LPS). EPDA suppressed the production of monocyte chemoattractant protein-1 (MCP-1), and interleukin-6 (IL-6) in both cell lines, and nitric oxide (NO), and macrophage-inflammatory protein-3α (MIP3A) in RAW 264.7 macrophages. At a transcriptional level, EPDA attenuated cyclooxygenase-2 (COX-2) expression in both cell lines and that of MCP-1, IL-6, and interleukin-1β (IL-1β) in THP-1 macrophages. Although further research is needed to reveal whether EPDA is an endogenous metabolite, our data suggest that this EPA-derived conjugate possesses interesting immune-modulating properties.

Functional link between plasma membrane spatiotemporal dynamics, cancer biology, and dietary membrane-altering agents

The cell plasma membrane serves as a nexus integrating extra- and intracellular components, which together enable many of the fundamental cellular signaling processes that sustain life. In order to perform this key function, plasma membrane components assemble into well-defined domains exhibiting distinct biochemical and biophysical properties that modulate various signaling events. Dysregulation of these highly dynamic membrane domains can promote oncogenic signaling. Recently, it has been demonstrated that select membrane-targeted dietary bioactives (MTDBs) have the ability to remodel plasma membrane domains and subsequently reduce cancer risk. In this review, we focus on the importance of plasma membrane domain structural and signaling functionalities as well as how loss of membrane homeostasis can drive aberrant signaling. Additionally, we discuss the intricacies associated with the investigation of these membrane domain features and their associations with cancer biology. Lastly, we describe the current literature focusing on MTDBs, including mechanisms of chemoprevention and therapeutics in order to establish a functional link between these membrane-altering biomolecules, tuning of plasma membrane hierarchal organization, and their implications in cancer prevention.

Serum Polyunsaturated Fatty Acids Correlate with Serum Cytokines and Clinical Disease Activity in Crohn's Disease

Crohn’s disease (CD) has been associated with an increased consumption of n-6 polyunsaturated fatty acid (PUFA), while greater intake of n-3 PUFA has been associated with a reduced risk. We sought to investigate serum fatty acid composition in CD, and associations of fatty acids with disease activity, cytokines, and adipokines. Serum was prospectively collected from 116 CD subjects and 27 non-IBD controls. Clinical disease activity was assessed by the Harvey Bradshaw Index (HBI). Serum fatty acids were measured by gas chromatography. Serum cytokines and adipokines were measured by Luminex assay. Dietary histories were obtained from a subset of patients. Nine serum cytokines and adipokines were increased in CD versus controls. CD subjects had increased percentage serum monounsaturated fatty acids (MUFA), dihomo-gamma linolenic acid (DGLA), eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), and oleic acid, but decreased arachidonic acid (AA) versus controls. The % total n-3 fatty acids and % EPA directly correlated with pro-inflammatory cytokine levels and HBI, whereas the % total n-6 fatty acids were inversely correlated with pro-inflammatory cytokine levels and HBI. CD subjects had increased caloric intake versus controls, but no alterations in total fat or PUFA intake. We found differences in serum fatty acids, most notably PUFA, in CD that correlated both with clinical disease activity and inflammatory cytokines. Our findings indicate that altered fatty acid metabolism or utilization is present in CD and is related to disease activity.

Dietary Long-Chain n-3 Fatty Acid Intake and Arthritis Risk in the Women's Health Initiative

BACKGROUND

The prevalence of arthritis in the United States is substantial and on the rise. Long-chain n-3 polyunsaturated fatty acids, which have anti-inflammatory properties, have been shown to provide therapeutic benefit to arthritis patients; however, to date few have examined these associations with arthritis risk.

OBJECTIVE

The study objective was to examine the associations of long-chain n-3 polyunsaturated fatty acids intake with osteoarthritis (OA) and rheumatoid arthritis (RA) risk among postmenopausal women.

DESIGN

This was a prospective cohort study.

PARTICIPANTS

The sample for this analysis consisted of 80,551 postmenopausal women, aged 55 to 79 years and with no history of arthritis, recruited into the Women's Health Initiative Observational Study and Clinical Trials cohort between 1993 and 1998. Women completed a 120-item food frequency questionnaire at baseline.

MAIN OUTCOME MEASURES

After a median follow-up of 8 years, 22,306 incident OA and 3,348 RA cases were identified.

STATISTICAL ANALYSES PERFORMED

Adjusted Cox regression models were used to estimate hazard ratios and 95% CI for the associations between dietary LCn-3PUFA intake and OA and RA risk.

RESULTS

Individual and total long-chain n-3 polyunsaturated fatty acids (Quintile 5 vs Quintile 1: hazard ratio 1.04, 95% CI 0.99 to 1.09 for OA; hazard ratio 1.01, 95% CI 0.90 to 1.13 for RA) were not associated with OA and RA risk. Further, no associations were observed between n-6 polyunsaturated fatty acids intake and either arthritis outcome.

CONCLUSIONS

This study is the first to examine associations of long-chain n-3 polyunsaturated fatty acids intake with OA risk and the largest to examine associations with RA risk. Despite their therapeutic potential, the study provides no evidence of benefit of these nutrients in relation to arthritis risk.

Maternal and Postnatal Supplementation of Fish Oil Improves Metabolic Health of Mouse Male Offspring

OBJECTIVE

Over half of American women of childbearing age have either obesity or overweight. Hence, maternal programming through diet is critical for prevention of diseases in the offspring. Clinical trials with fish oil (FO) report various health benefits; however, it remains unclear whether maternal and postnatal consumption of FO protects offspring from adverse effects of consuming a high-fat (HF) diet.

METHODS

Female mice were fed HF diets supplemented without (HF) or with FO from 8 weeks before pregnancy through lactation. A low-fat (LF) diet was included as a control diet. After weaning, male offspring from HF or FO dams were either continued on their respective diet (HF-HF and FO-FO) or switched to the other diet (HF-FO and FO-HF) and compared with LF. Phenotypic and mechanistic studies were performed.

RESULTS

FO-FO offspring demonstrated significantly higher glucose clearance and insulin sensitivity compared with other pups fed the HF diet (P < 0.05). Furthermore, FO-FO pups had lower adiposity, inflammation, and fat deposition in the liver, consistent with reduced markers of hepatic lipogenesis and increased hepatic lipid oxidation.

CONCLUSIONS

Supplementation of FO during pregnancy and early life is more beneficial than treating with FO either during pregnancy or in pups.

Dietary Intake of Omega-3 fatty acids and Endocrine-related Gynecological Cancer: A Meta-Analysis of Observational Studies

Purpose

Previous observational epidemiological studies have reported inconsistent findings on the association between dietary intake of omega-3 fatty acids and endocrine-related gynecological cancer such as ovarian cancer and endometrial cancer. This study aimed to investigate this association using a meta-analysis of observational studies.

Materials and Methods

We searched PubMed, EMBASE, and Cochrane library by using key words related with the topic in April 2017. The pooled odd ratios (pORs), relative risks (pRRs), or hazard ratios (pHRs) with 95% confidence intervals (CIs) were calculated based on the random-effects model. Also, we performed subgroup meta-analysis by methodological quality, types of cancer, study design, and omega-3 fatty acids.

Results

A total of ten observational studies with six case-control and four cohort studies were included in the final meta-analysis. In the meta-analysis of all the studies, dietary intake of total omega-3 fatty acids was not significantly associated with the risk of endometrial and ovarian cancers (pOR/HR, 0.87; 95% CI, 0.73-1.04; I²=67.2%) (highest versus lowest intake). In the subgroup meta-analysis by type of study, there was no significant association between them in cohort studies (pHR, 1.03; 95% CI, 0.63-1.67, I²=81.9%), whereas its reduced risk was observed in case-control studies (pOR, 0.81; 95% CI, 0.67 to 0.98, I²=55.7%).

Conclusion

The current meta-analysis of observational studies suggests that there is no higher level of evidence to support the protective effect of dietary omega-3 fatty acids on endocrine-related gynecological cancer. Further prospective studies should be conducted to confirm the association.

The Benefit of Anti-Inflammatory and Renal-Protective Dietary Ingredients on the Biological Processes of Aging in the Kidney

One of the significant organ systems which decline in aging is the kidney. While the causes of age-associated decline in renal function are likely multifactorial, oxidative stress and inflammation are hypothesized to play important roles in the structural and functional changes of the kidney. During aging there is a general decline in the glomerular filtration rate (GFR), a primary measurement used to assess kidney function. Inflammation and oxidative stress have been hypothesized to have a significant detrimental effect on renal function in aging and this may be attenuated by renal protective dietary ingredients. These dietary ingredients may affect renal function directly or through a microbiome-mediated secondary product. Likewise, structural changes including renal tubular atrophy, interstitial fibrosis, and glomerulosclerosis have all been described in aging. Such detrimental changes may benefit from dietary ingredients that may delay or attenuate the occurrence of such changes. This review will describe the physiology and pathophysiology of aging in renal function with an emphasis on dogs and cats that develop a decline in kidney function naturally. In addition, the varying biomarkers of health and renal dysfunction will be discussed. Finally, we will evaluate the aid in the management of this normal decline through dietary intervention in animal models.

Omega-3 Fatty Acids Attenuate Brain Alterations in High-Fat Diet-Induced Obesity Model

This study evaluated the effects of omega-3 on inflammation, oxidative stress, and energy metabolism parameters in the brain of mice subjected to high-fat diet-induced obesity model. Body weight and visceral fat weight were evaluated as well. Male Swiss mice were divided into control (purified low-fat diet) and obese (purified high-fat diet). After 6 weeks, the groups were divided into control + saline, control + omega-3, obese + saline, and obese + OMEGA-3. Fish oil (400 mg/kg/day) or saline solution was administrated orally, during 4 weeks. When the experiment completed 10 weeks, the animals were euthanized and the brain and visceral fat were removed. The brain structures (hypothalamus, hippocampus, prefrontal cortex, and striatum) were isolated. Treatment with omega-3 had no effect on body weight, but reduced the visceral fat. Obese animals showed increased inflammation, increased oxidative damage, decreased antioxidant enzymes activity and levels, changes in the Krebs cycle enzyme activities, and inhibition of mitochondrial respiratory chain complexes in the brain structures. Omega-3 treatment partially reversed the changes in the inflammatory and in the oxidative damage parameters and attenuated the alterations in the antioxidant defense and in the energy metabolism (Krebs cycle and mitochondrial respiratory chain). Omega-3 had a beneficial effect on the brain of obese animals, as it partially reversed the changes caused by the consumption of a high-fat diet and consequent obesity. Our results support studies that indicate omega-3 may contribute to obesity treatment.

Effect of bovine milk fat globule membranes as a complementary food on the serum metabolome and immune markers of 6-11-month-old Peruvian infants

This study builds on a previous study by this group in which 6–11-month-old Peruvian infants who were fed bovine milk fat globule membrane (MFGM) containing complementary food had significantly fewer episodes of infection-related bloody diarrhea relative to those consuming a control food (skim milk powder). Micronutrient deficiencies including zinc deficiency were prevalent in this study population. To understand the mechanism behind the health benefits of consuming MFGM, the serum metabolome and cytokine levels, as markers for systemic immune responses, were evaluated using ¹H nuclear magnetic resonance-based metabolomics and a multiplex system, respectively. Combined with data on micronutrient status and anthropometry, a comparative analysis was performed. Supplementation with MFGM tended to improve micronutrient status, energy metabolism, and growth reflected as increased levels of circulating amino acids and weight gain, particularly in female infants compared to controls. Decreased levels of the microbial choline metabolite trimethylamine-N-oxide in the MFGM-supplemented group (both male and female infants) suggest a functional perturbation in the intestinal microbiota. A cytokine shift toward a less T helper type 1 response was observed in those receiving the MFGM supplement, which was mainly attributed to decreases in interleukin-2 levels. Our findings suggest that consumption of MFGM with complementary food may reverse the metabolic abnormalities found in marginally nourished infants, thereby improving metabolic regulation, which may lead to enhanced immunity.

Bovine milk fat globule membrane (MFGM)-enriched complementary food has been recognized to be capable of reducing the episodes of bloody diarrhea in marginally nourished infants. However, the metabolic influence of MFGM remains unknown. Carolyn Slupsky from University of California-Davis and co-workers studied the impacts of bovine MFGM consumption on the levels of serum metabolome and immune markers. They found the supplements of MFGM improved the micronutrient status, energy metabolism, and growth, especially prominent for female infants. Moreover, MFGM complementary food lowered the level of the bacterial choline metabolite trimethylamine-N-oxide in the infants, indicating a functional perturbation to their intestinal microbiota. These findings suggest MFGM in complementary food can help to regulate the metabolic abnormalities of the infants with micronutrient deficiency, probably resulting in enhanced immunity.

n-3 PUFA and obesity: from peripheral tissues to the central nervous system

The current paradigms of prevention and treatment are unable to curb obesity rates, which indicates the need to explore alternative therapeutic approaches. Obesity leads to several damages to the body and is an important risk factor for a number of other chronic diseases. Furthermore, despite the first alterations in obesity being observed and reported in peripheral tissues, studies indicate that obesity can also cause brain damage. Obesity leads to a chronic low-grade inflammatory state, and the therapeutic manipulation of inflammation can be explored. In this context, the use of n-3 PUFA (especially in the form of fish oil, rich in EPA and DHA) may be an interesting strategy, as this substance is known by its anti-inflammatory effect and numerous benefits to the body, such as reduction of TAG, cardiac arrhythmias, blood pressure and platelet aggregation, and has shown potential to help treat obesity. Thereby, the aim of this narrative review was to summarise the literature related to n-3 PUFA use in obesity treatment. First, the review provides a brief description of the obesity pathophysiology, including alterations that occur in peripheral tissues and at the central nervous system. In the sequence, we describe what are n-3 PUFA, their sources and their general effects. Finally, we explore the main topic linking obesity and n-3 PUFA. Animal and human studies were included and alterations on the whole organism were described (peripheral tissues and brain).

A Randomized Multicenter Phase II Study of Docosahexaenoic Acid in Patients with a History of Breast Cancer, Premalignant Lesions, or Benign Breast Disease

Obesity, a cause of subclinical inflammation, is a risk factor for the development of postmenopausal breast cancer and is associated with poorer cancer outcomes. Docosahexaenoic acid (DHA), an omega-3 fatty acid, possesses anti-inflammatory properties. We hypothesized that treatment with DHA would reduce the expression of proinflammatory genes and aromatase, the rate-limiting enzyme for estrogen biosynthesis, in benign breast tissue of overweight/obese women. A randomized, placebo-controlled, double-blind phase II study of DHA given for 12 weeks to overweight/obese women with a history of stage I-III breast cancer, DCIS/LCIS, Paget's disease, or proliferative benign breast disease was carried out. In this placebo controlled trial, the primary objective was to determine whether DHA (1,000 mg by mouth twice daily) reduced breast tissue levels of TNFα. Secondary objectives included evaluation of the effect of DHA on breast tissue levels of COX-2, IL1β, aromatase, white adipose tissue inflammation, and gene expression by RNA-seq. Red blood cell fatty acid levels were measured to assess compliance. From July 2013 to November 2015, 64 participants were randomized and treated on trial (32 women per arm). Increased levels of omega-3 fatty acids in red blood cells were detected following treatment with DHA (P < 0.001) but not placebo. Treatment with DHA did not alter levels of TNFα (P = 0.71), or other biomarkers including the transcriptome in breast samples. Treatment with DHA was overall well-tolerated. Although compliance was confirmed, we did not observe changes in the levels of prespecified biomarkers in the breast after treatment with DHA when compared with placebo. Cancer Prev Res; 11(4); 203-14. ©2018 AACRSee related editorial by Fabian and Kimler, p. 187.

Omega-3 Fatty Acids Reduce Inflammation in Rat Apical Periodontitis

INTRODUCTION

The effects of omega-3 polyunsaturated fatty acids (ω-3 PUFAs) on pro- and anti-inflammatory mediators were evaluated in a rat model of pulp exposure-induced apical periodontitis (AP).

METHODS

Twenty-eight male Wistar rats were divided into 4 groups: control, untreated rats (group C); control rats treated with ω-3 PUFAs (group C-O); rats with pulp exposure-induced AP (group AP); and rats with pulp exposure-induced AP treated with ω-3 PUFAs (group AP-O). Omega-3 PUFAs were administered orally once a day for 15 days before pulp exposure; this treatment was continued for 30 days after pulp exposure. The rats were sacrificed 30 days after pulp exposure, and their dissected jaws were subjected to immunohistochemical analysis to detect immunoreactivity for tumor necrosis factor alpha (TNF-α), interleukin (IL)-6, IL-1β, IL-17, and IL-10 on the periapical bone surface. The results were statistically evaluated using analysis of variance and the Tukey post-test. The significance level was set at 5%.

RESULTS

Immunoreactivity for the proinflammatory cytokines TNF-α, IL-6, IL-1β, and IL-17 was higher in the AP group than in the AP-O, C, and C-O groups (P < .05). Immunoreactivity for the anti-inflammatory cytokine IL-10 was lower in the AP group than in the AP-O group (P < .05).

CONCLUSIONS

Supplementation with ω-3 PUFAs can modulate the inflammatory response in rat AP, decreasing levels of TNF-α, IL-6, IL-1β, and IL-17 but increasing levels of IL-10.