The omega-3 fatty acid docosahexaenoic acid favorably modulates the inflammatory pathways and macrophage polarization within aorta of LDLR(-/-) mice

Prevention of Chronic Morbidities in Extremely Premature Newborns with LISA-nCPAP Respiratory Therapy and Adjuvant Perinatal Strategies

Less invasive surfactant administration techniques, together with nasal continuous airway pressure (LISA-nCPAP) ventilation, an emerging noninvasive ventilation (NIV) technique in neonatology, are gaining more significance, even in extremely premature newborns (ELBW), under 27 weeks of gestational age. In this review, studies on LISA-nCPAP are compiled with an emphasis on short- and long-term morbidities associated with prematurity. Several perinatal preventative and therapeutic investigations are also discussed in order to start integrated therapies as numerous organ-saving techniques in addition to lung-protective ventilations. Two thirds of immature newborns can start their lives on NIV, and one third of them never need mechanical ventilation. With adjuvant intervention, these ratios are expected to be increased, resulting in better outcomes. Optimized cardiopulmonary transition, especially physiologic cord clamping, could have an additively beneficial effect on patient outcomes gained from NIV. Organ development and angiogenesis are strictly linked not only in the immature lung and retina, but also possibly in the kidney, and optimized interventions using angiogenic growth factors could lead to better morbidity-free survival. Corticosteroids, caffeine, insulin, thyroid hormones, antioxidants, N-acetylcysteine, and, moreover, the immunomodulatory components of mother's milk are also discussed as adjuvant treatments, since immature newborns deserve more complex neonatal interventions.

Resveratrol and ω-3 PUFAs Promote Human Macrophage Differentiation and Function

Monocytes differentiate into M1 and M2 macrophages, which are classically activated by microbial products such as LPS or IFN-γ and interleukins (e.g., the anti-inflammatory and T_h2 promoting IL-4), respectively. The contribution of nutrients or nutrient-based substances such as ω-3 polyunsaturated fatty acids (ω-3 PUFAs) and resveratrol (Res) on the differentiation and function of M1 and M2 macrophages was evaluated. THP-1 cells and peripheral blood mononuclear cells (PBMCs) were differentiated into M1 and M2 cells and activated with LPS/IFN-γ or IL-4/IL-13. Macrophage lineage specific surface determinants (e.g., CD11b, CD11c, CD14, CD206, CD209, CD274, HLA-DR, CCR7, CCR2) were analysed by cytofluorometry. Res and ω-3 PUFAs altered CD14, CD206, CD274 and HL-DR surface expression patterns in M1 and M2 macrophages differentiated from PBMC. LPS/IFN-γ or IL-14/IL-13 activated macrophages subpopulations, which secreted cytokines and chemokines as measured by multiplex ELISA. Res and ω-3 PUFA reduced IL-1β, IL-6, TNF-α, CXCL10/IP-10, CCL13/MCP-4 and CCL20/MIP-3α in LPS/IFN-γ activated human leukaemia THP-1 cells, which is indicative of a dampening effect on M1 macrophages. However, Res increased M1 prototypic cytokines such as IL-1β or IL-6 in macrophages derived from PBMCs and also modified the expression of IL-12p70. Collectively, Res and ω-3 PUFAs distinctly promoted the differentiation and function of M1 and M2 macrophages. We conclude that these substances strengthen the macrophage-mediated effects on the innate and adaptive immune response.

Multifunctional Role of Lipids in Modulating the Tumorigenic Properties of 4T1 Breast Cancer Cells

Tumor growth and progression are linked to an altered lipid metabolism in the tumor microenvironment (TME), including tumor cells and tumor-associated macrophages (TAMs). A growing number of lipid metabolism targeting drugs have shown efficacy in anti-tumor therapy. In addition, exogenously applied lipids and lipid analogues have demonstrated anti-tumor activities in several cancers, including breast cancer. In this study, we investigated the anti-tumor efficacies of the natural lipids palmitic acid (PA), sphingomyelin (SM), ceramide (Cer) and docosahexaenoic acid (DHA) on breast cancer cells. All tested lipids reduced the malignancy of breast cancer cells in vitro by impairing cell proliferation, migration and invasiveness. PA showed superior anti-tumor properties, as it additionally impaired cancer cell viability by inducing apoptosis, without affecting healthy cells. Co-culture experiments further demonstrated that Cer and PA reduced the immunosuppressive phenotype of M2 macrophages and the M2 macrophage-promoted the epithelial–mesenchymal transition (EMT) and migration of breast cancer cells. At the molecular level, this coincided with the up-regulation of E-cadherin. Our results highlight a powerful role for exogenously applied PA and Cer in reducing breast cancer tumorigenicity by simultaneously targeting cancer cells and M2 macrophages. Our findings support the notion that lipids represent alternative biocompatible therapeutic agents for breast cancer.

Effect of Docosahexaenoic Acid (DHA) at the Enteric Level in a Synucleinopathy Mouse Model

The aggregation of alpha-synuclein protein (αSyn) is a hallmark of Parkinson’s disease (PD). Considerable evidence suggests that PD involves an early aggregation of αSyn in the enteric nervous system (ENS), spreading to the brain. While it has previously been reported that omega-3 polyunsaturated fatty acids (ω-3 PUFA) acts as neuroprotective agents in the brain in murine models of PD, their effect in the ENS remains undefined. Here, we studied the effect of dietary supplementation with docosahexaenoic acid (DHA, an ω-3 PUFA), on the ENS, with a particular focus on enteric dopaminergic (DAergic) neurons. Thy1-αSyn mice, which overexpress human αSyn, were fed ad libitum with a control diet, a low ω-3 PUFA diet or a diet supplemented with microencapsulated DHA and then compared with wild-type littermates. Our data indicate that Thy1-αSyn mice showed a lower density of enteric dopaminergic neurons compared with non-transgenic animals. This decrease was prevented by dietary DHA. Although we found that DHA reduced microgliosis in the striatum, we did not observe any evidence of peripheral inflammation. However, we showed that dietary intake of DHA promoted a build-up of ω-3 PUFA-derived endocannabinoid (eCB)-like mediators in plasma and an increase in glucagon-like peptide-1 (GLP-1) and the redox regulator, Nrf2 in the ENS. Taken together, our results suggest that DHA exerts neuroprotection of enteric DAergic neurons in the Thy1-αSyn mice, possibly through alterations in eCB-like mediators, GLP-1 and Nrf2.

Efficacy of choline and DHA supplements or enriched environment exposure during early adult obesity in mitigating its adverse impact through aging in rats

INTRODUCTION

The aim of this study was to assess the efficacy of choline and DHA or exposure to environmental enrichment in obese adult and aging rats on alterations in body mass index, serum lipid profile and arterial wall changes, despite stopping high fat diet consumption and interventions during adulthood.

METHODS

21 day old male Sprague Dawley rats were assigned as Experiment-1 & 2 - PND rats were divided into 4 groups with interventions for 7 months (n = 8/group). NC- Normal control fed normal chow diet; OB- Obese group, fed high fat diet; OB + CHO + DHA- fed high fat diet and oral supplementation of choline, DHA. OB + EE- fed high fat diet along with exposure to enriched environment .Experiment-2 had similar groups and interventions as experiment 1 but for next 5 months were fed normal chow diet without any interventions. Body mass index was assessed and blood was analyzed for serum lipid profile. Common Carotid Artery (CCA) was processed for Haematoxylin and eosin, Verhoff Vangeison stains. Images of tissue sections were analyzed and quantified using image J and tissue quant software.

RESULTS

In experiment.1, mean body mass index (p < 0.001), serum lipid profile (p < 0.01), thickness of tunica intima (p < 0.05), tunica media (p < 0.01) and percentage of collagen fibers (p < 0.01) of CCA were significantly increased in OB compared to NC. These were significantly attenuated in OB + CHO + DHA and OB + EE compared to OB. In experiment.2, mean body mass index (p < 0.01), serum lipid profile (p < 0.05) and thickness of tunica media of CCA (p < 0.01) were significantly increased in OB compared to NC. In OB + CHO + DHA and OB + EE, significant attenuation was observed in mean body mass index and mean thickness of tunica media compared to same in OB.

CONCLUSION

Adult obesity has negative impact on body mass index, serum lipid profile and arterial wall structure that persists through aging. Supplementation of choline and DHA or exposure to enriched environment during obesity attenuates these negative impacts through aging.

Current Research Landscape of Marine-Derived Anti-Atherosclerotic Substances

Atherosclerosis is a chronic disease characterized by lipid accumulation and chronic inflammation of the arterial wall, which is the pathological basis for coronary heart disease, cerebrovascular disease and thromboembolic disease. Currently, there is a lack of low-cost therapeutic agents that effectively slow the progression of atherosclerosis. Therefore, the development of new drugs is urgently needed. The research and development of marine-derived drugs have gained increasing interest from researchers across the world. Many marine organisms provide a rich material basis for the development of atherosclerotic drugs. This review focuses on the latest technological advances in the structures and mechanisms of action of marine-derived anti-atherosclerotic substances and the challenges of the application of these substances including marine polysaccharides, proteins and peptides, polyunsaturated fatty acids and small molecule compounds. Here, we describe the theoretical basis of marine biological resources in the treatment of atherosclerosis.

Effects of n-3 fatty acid treatment on monocyte phenotypes in humans with hypertriglyceridemia

BACKGROUND

Hypertriglyceridemia increases risk for atherosclerotic cardiovascular disease and may contribute to atherosclerosis by changing circulating monocyte phenotypes. High-dose n-3 polyunsaturated fatty acids reduce blood triglyceride levels. Effects of triglyceride-lowering therapy on monocyte phenotypes are not well known.

OBJECTIVE

We examined effects of n-3 polyunsaturated fatty acid treatments (eicosapentaenoic acid [EPA] plus docosapentaenoic acid [MAT9001] vs EPA ethyl esters [EPA-EE]) on monocyte phenotypes in individuals with hypertriglyceridemia.

METHODS

Individuals with triglycerides 200 to 400 mg/dL were recruited. Subjects received 2 treatments in randomized order for 14 days each: MAT9001 and EPA-EE, at 4 g/d. At 2 days before the start of, and on the last day of, each treatment, nile red staining for lipids and phenotypes of each monocyte subset were examined by flow cytometry after an overnight fast and postprandially after a high-fat meal.

RESULTS

Treatment with MAT9001 or EPA-EE reduced fasting triglyceride levels and decreased proportions of intermediate monocytes. Only MAT9001 decreased postprandial blood triglyceride levels, lowered fasting nile red levels, indicating less lipid in classical and intermediate monocytes, and reduced postprandial CD11c levels on nonclassical monocytes. MAT9001 and EPA-EE each reduced fasting and postprandial CD11c and CD36 levels on classical and intermediate monocytes and postprandial CCR5 levels on intermediate and nonclassical monocytes, with no significant differences between the 2 treatments.

CONCLUSIONS

Treatment with MAT9001 in individuals with hypertriglyceridemia reduced fasting nile red staining for lipids in classical and intermediate monocytes. MAT9001 and EPA-EE each improved fasting and postprandial monocyte phenotypes, which could potentially help to protect against atherosclerosis.

DHA-derived oxylipins, neuroprostanes and protectins, differentially and dose-dependently modulate the inflammatory response in human macrophages: Putative mechanisms through PPAR activation

Whereas the anti-inflammatory properties and mechanisms of action of long chain ω3 PUFAs have been abundantly investigated, research gaps remain regarding the respective contribution and mechanisms of action of their oxygenated metabolites collectively known as oxylipins. We conducted a dose-dependent and comparative study in human primary macrophages aiming to compare the anti-inflammatory activity of two types of DHA-derived oxylipins including the well-described protectins (NPD1 and PDX), formed through lipoxygenase pathway and the neuroprostanes (14-A_4t- and 4-F_4t-NeuroP) formed through free-radical mediated oxygenation and expected to be new anti-inflammatory mediators. Considering the potential ability of these DHA-derived oxylipins to bind PPARs and knowing the central role of these transcription factors in the regulation of macrophage inflammatory response, we performed transactivation assays to compare the ability of protectins and neuroprostanes to activate PPARs. All molecules significantly reduced mRNA levels of cytokines such as IL-6 and TNF-α, however not at the same doses. NPD1 showed the most effect at 0.1µM (-14.9%, p<0.05 for IL-6 and -26.7%, p<0.05 for TNF-α) while the three other molecules had greater effects at 10µM, with the strongest result due to the cyclopentenone neuroprostane, 14-A_4t-NeuroP (-49.8%, p<0.001 and -40.8%, p<0.001, respectively). Part of the anti-inflammatory properties of the DHA-derived oxylipins investigated could be linked to their activation of PPARs. Indeed, all tested oxylipins significantly activated PPARγ, with 14-A_4t-NeuroP leading to the strongest activation, and NPD1 and PDX also activated PPARα. In conclusion, our results show that neuroprostanes and more especially cyclopentenone neuroprostanes have potent anti-inflammatory activities similar or even more pronounced than protectins supporting that neuroprostanes should be considered as important contributors to the anti-inflammatory effects of DHA.

Role of Inflammatory Signaling in the Differential Effects of Saturated and Poly-unsaturated Fatty Acids on Peripheral Circadian Clocks

Inflammatory signaling may play a role in high-fat diet (HFD)-related circadian clock disturbances that contribute to systemic metabolic dysregulation. Therefore, palmitate, the prevalent proinflammatory saturated fatty acid (SFA) in HFD and the anti-inflammatory, poly-unsaturated fatty acid (PUFA), docosahexaenoic acid (DHA), were analyzed for effects on circadian timekeeping and inflammatory responses in peripheral clocks. Prolonged palmitate, but not DHA, exposure increased the period of fibroblast Bmal1-dLuc rhythms. Acute palmitate treatment produced phase shifts of the Bmal1-dLuc rhythm that were larger in amplitude as compared to DHA. These phase-shifting effects were time-dependent and contemporaneous with rhythmic changes in palmitate-induced inflammatory responses. Fibroblast and differentiated adipocyte clocks exhibited cell-specific differences in the time-dependent nature of palmitate-induced shifts and inflammation. DHA and other inhibitors of inflammatory signaling (AICAR, cardamonin) repressed palmitate-induced proinflammatory responses and phase shifts of the fibroblast clock, suggesting that SFA-mediated inflammatory signaling may feed back to modulate circadian timekeeping in peripheral clocks.

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The saturated fatty acid (SFA) palmitate differentially modulates the circadian timekeeping mechanism in peripheral clocks;

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Palmitate induces time-dependent phase shifts that coincide with its rhythmic induction of inflammatory signaling;

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Time-dependent nature of the palmitate-induced phase shifts and inflammatory signaling is cell specific;

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Inhibitors of inflammatory signaling repress the proinflammatory and phase shifting effects of palmitate;

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Inflammatory signaling plays a role in the mechanism by which palmitate alters circadian timekeeping in peripheral clocks.

Circadian or 24-hour clocks throughout the body mediate the local temporal coordination of tissue- or cell-specific processes necessary for normal inflammatory responses and metabolic homeostasis. Dysregulation of peripheral clocks and their timekeeping function contribute to obesity-related metabolic disorders (e.g., type 2 diabetes). Our data unveil a novel mechanism by which mutual interactions between peripheral clocks and inflammatory signaling pathways dysregulate circadian timekeeping, and exacerbate proinflammatory responses to saturated fatty acids. These studies will guide the development of chronotherapeutic drug and/or dietary omega-3 fatty acid treatments for managing and preventing metabolic disorders and other inflammation-related pathologies (e.g., cardiovascular disease, stroke, arthritis).

DHA Suppresses Primary Macrophage Inflammatory Responses via Notch 1/ Jagged 1 Signaling

Persistent macrophages were observed in the lungs of murine offspring exposed to maternal LPS and neonatal hyperoxia. Maternal docosahexaenoic acid (DHA) supplementation prevented the accumulation of macrophages and improved lung development. We hypothesized that these macrophages are responsible for pathologies observed in this model and the effects of DHA supplementation. Primary macrophages were isolated from adult mice fed standard chow, control diets, or DHA supplemented diets. Macrophages were exposed to hyperoxia (O₂) for 24 h and LPS for 6 h or 24 h. Our data demonstrate significant attenuation of Notch 1 and Jagged 1 protein levels in response to DHA supplementation in vivo but similar results were not evident in macrophages isolated from mice fed standard chow and supplemented with DHA in vitro. Co-culture of activated macrophages with MLE12 epithelial cells resulted in the release of high mobility group box 1 and leukotriene B₄ from the epithelial cells and this release was attenuated by DHA supplementation. Collectively, our data indicate that long term supplementation with DHA as observed in vivo, resulted in deceased Notch 1/Jagged 1 protein expression however, DHA supplementation in vitro was sufficient to suppress release LTB₄ and to protect epithelial cells in co-culture.

Role of taurine in the pathogenesis of obesity

Taurine is a sulfur-containing amino acid that is present in mammalian tissues in millimolar concentrations. Taurine is involved in a diverse array of biological and physiological functions, including bile salt conjugation, osmoregulation, membrane stabilization, calcium modulation, anti-oxidation, and immunomodulation. The prevalence of obesity and being overweight continues to rise worldwide at an alarming rate. Obesity is associated with a higher risk of metabolic and cardiovascular diseases, cancer, and other clinical conditions. Ingestion of taurine has been shown to alleviate metabolic diseases such as hyperlipidemia, diabetes, hypertension, and obesity in animal models. A global epidemiological survey showed that 24-h urinary taurine excretion, as a marker of dietary taurine intake, was inversely associated with BMI, blood pressure, and plasma cholesterol in humans. In addition, taurine chloramine, an endogenous product derived from activated neutrophils, has been reported to suppress obesity-induced oxidative stress and inflammation in adipocytes. Synthetic activity and concentration of taurine in adipose tissues and plasma have been shown to decrease in humans and animals during the development of obesity, suggesting a relationship between taurine deficiency and obesity. In this review, I summarize the effects of taurine on the progression of obesity in animal models and humans. Furthermore, I discuss possible mechanisms underlying the antiobesity effects of taurine.