Effects of the flavonol quercetin and α -linolenic acid on n -3 PUFA status in metabolically healthy men and women: a randomised, double-blinded, placebo-controlled, crossover trial

Perilla seed oil in combination with the nobiletin-rich ponkan powder enhances cognitive function in healthy elderly Japanese individuals: Possible supplement for brain health in the elderly

Perilla (Perilla frutescens) seed oil (PO), rich in α-linolenic acid (ALA), can improve cognitive function in healthy elderly Japanese people. Here, supplements containing either PO alone or PO with nobiletin-rich...

Eicosapentaenoic Acid Is Associated with Decreased Incidence of Alzheimer's Dementia in the Oldest Old

BACKGROUND

Omega-3 (n-3) and omega-6 (n-6) polyunsaturated fatty acids (PUFAs) may have different effects on cognitive health due to their anti- or pro-inflammatory properties.

METHODS

We aimed to prospectively examine the relationships between n-3 and n-6 PUFA contents in serum phospholipids with incident all-cause dementia and Alzheimer's disease dementia (AD). We included 1264 non-demented participants aged 84 ± 3 years from the German Study on Ageing, Cognition, and Dementia in Primary Care Patients (AgeCoDe) multicenter-cohort study. We investigated whether fatty acid concentrations in serum phospholipids, especially eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), alpha-linolenic acid (ALA), linoleic acid (LA), dihomo-γ-linolenic acid (DGLA), and arachidonic acid (AA), were associated with risk of incident all-cause dementia and AD.

RESULTS

During the follow-up window of seven years, 233 participants developed dementia. Higher concentrations of EPA were associated with a lower incidence of AD (hazard ratio (HR) 0.76 (95% CI 0.63; 0.93)). We also observed that higher concentrations of EPA were associated with a decreased risk for all-cause dementia (HR 0.76 (95% CI 0.61; 0.94)) and AD (HR 0.66 (95% CI 0.51; 0.85)) among apolipoprotein E ε4 (APOE ε4) non-carriers but not among APOE ε4 carriers. No other fatty acids were significantly associated with AD or dementia.

CONCLUSIONS

Higher concentrations of EPA were associated with a lower risk of incident AD. This further supports a beneficial role of n-3 PUFAs for cognitive health in old age.

New and traditional foods in a modernized Mediterranean diet model

Mediterranean diet is definitely one of the healthiest dietary models. Next questions are: is the traditional Mediterranean diet adapted to the modern environmental and existential conditions? Could and/or should it be "modernized" to adapt to the various geographical, environmental, ethnic, and religious characteristics? If "modernization" is required, which traditional Mediterranean foods should be imperatively conserved as they are? Alternatively, which "new" foods-not traditional or not Mediterranean-could be introduced to help people to still respect the basic healthy Mediterranean diet principles? The present article intends to help solving these new questions.

Functional Foods: Product Development, Technological Trends, Efficacy Testing, and Safety

Functional foods is a very popular term in the social and scientific media; consequently, food producers have invested resources in the development of processed foods that may provide added functional benefits to consumers' well-being. Because of intrinsic regulation and end-of-use purposes in different countries, worldwide meanings and definitions of this term are still unclear. Hence, here we standardize this definition and propose a guideline to attest that some ingredients or foods truly deserve this special designation. Furthermore, focus is directed at the most recent studies and practical guidelines that can be used to develop and test the efficacy of potentially functional foods and ingredients. The most widespread functional ingredients, such as polyunsaturated fatty acids (PUFAs), probiotics/prebiotics/synbiotics, and antioxidants, and their technological means of delivery in food products are described. The review discusses the steps that food companies should take to ensure that their developed food product is truly functional.

Onion Peel Extract Increases Erythrocyte Membrane n-3 Fatty Acids in Overweight and Obese Korean Subjects

The association between obesity and erythrocyte fatty acids (FAs) has been suggested; however, there have been no studies on the effects of onion peel extract (OPE) on the composition of erythrocyte FAs. This study aimed to investigate the effects of OPE on the composition of erythrocyte FAs in overweight and obese subjects. This was a randomized, double-blind, and placebo-controlled trial conducted in overweight and obese Korean subjects. The placebo and OPE groups were taking placebo capsule or OPE capsule twice per day for 12 weeks. Body composition and fat distribution were measured using dual-energy X-ray absorptiometry. The OPE group showed significantly reduced body weight, body mass index, body fat mass, and percentage of body fat mass. After 12 weeks, eicosapentaenoic acid and monounsaturated FAs of the placebo group were significantly lower at baseline. Consumption of OPE ameliorated the decreasing polyunsaturated n-3 polyunsaturated FA (PUFA) n-3 and increasing PUFA n-6, which prevented an increased n-6/n-3 ratio. The changes in arm fat percentage (ARFATP), trunk fat percentage, and total fat percentage (FATP) were negatively correlated with the change in PUFA n-3. In addition, increased erythrocyte docosahexaenoic acid was associated with decreased ARFATP and FATP. These results suggest that OPE has beneficial effects on obesity by regulating erythrocyte n-6/n-3 ratio and preventing fat accumulation in various body regions.

A minireview of quercetin: from its metabolism to possible mechanisms of its biological activities

Quercetin, one of the most taken flavonoid with diet, belongs to the family of flavonols in which kaempferol and myricetin are also found. Quercetin occurs as a glycoside (with linked sugars) or as an aglycone (without linked sugars). Although quercetin has many different forms in nature, the form found in plants is quercetin-3-O-glucoside, which generally functions as a pigment that gives color to a multitude of fruits and vegetables. The recent literature has been reviewed using PubMed, Science Direct, and Embase databases. In this article, we reviewed quercetin with respect to chemical properties, absorption mechanism, metabolism, bioavailability, food sources, bioactivities, and possible health-promoting mechanisms. Quercetin is known as an antioxidant, anti-inflammatory, cardioprotective, and anti-obesity compound. It is thought to be beneficial against cardiovascular diseases, cancer, diabetes, neurological diseases, obesity, allergy asthma, and atopic diseases. Further clinical studies with large sample sizes are needed to determine the appropriate dose and form of quercetin for preventing diseases.

Flavonoids as putative modulators of Δ4-, Δ5-, and Δ6-desaturases: Studies in cultured hepatocytes, myocytes, and adipocytes

This study was conducted to screen flavonoids for affecting expression of desaturases involved in omega-3 fatty acid synthesis and ceramide (CER) metabolism. To this end, cultured HepG2 hepatocytes, C2C12 myocytes, and 3T3-L1 adipocytes were treated with nontoxic concentrations of 12 selected flavonoids and expression of Δ4-, Δ5-, and Δ6-desaturases (DEGS1, FADS1, and FADS2, respectively) was determined. The flavonoids tested were more cytotoxic to HepG2 and 3T3-L1 than to C2C12 cells. In HepG2 cells, FADS1 was induced by quercetin and FADS2 expression was increased by daidzein, genistein, and pratensein treatment. DEGS1 was increased by apigenin, luteolin, orobol, and quercetin administration. In differentiated C2C12 cells, substances had no inducing effect or even lowered target gene expression. Pratensein induced both FADS1 and FADS2 in differentiated 3T3-L1 cells and DEGS1 was increased by treatment with apigenin, genistein, luteolin, orobol, and quercetin. In conclusion, pratensein may be an interesting test compound for further studies in vitro and in vivo on omega-3 synthesis since it induces its rate-limiting enzyme FADS2. Apigenin, luteolin, orobol, and quercetin induced DEGS1 and thereby possibly synthesis of proapoptotic CER in malignant HepG2 cells and 3T3-L1. In contrast, in benign C2C12 cells, they did not elevate mRNA steady state levels of DEGS1. That may partly explain the higher resistance of C2C12 cells against flavonoids compared to the other cell lines. By affecting tumor cells and nontumor cells differently, these flavonoids may be promising substances for further research regarding anticancer properties. © 2018 BioFactors, 44(5):485-495, 2018.

Interaction of Polyphenols with Other Food Components as a Means for Their Neurological Health Benefits

Over the last few years, there has been increasing interest in the possible beneficial effect of polyphenol consumption on neurodegenerative disorders. Because there is a clear impact of environmental factors on the onset and evolution of neurodegenerative conditions, food arises as a promising factor that might be influencing this group of pathologies. The mechanisms by which polyphenols can affect these processes can be through direct interaction with redox signaling or inflammatory pathways but can also be explained by the interaction of dietary polyphenols with either micro- and macronutrients that are known to have neurological effects or interaction with food contaminants or food-associated toxins, avoiding their neuronal toxicity.

Insights on Localized and Systemic Delivery of Redox-Based Therapeutics

Reactive oxygen and nitrogen species are indispensable in cellular physiology and signaling. Overproduction of these reactive species or failure to maintain their levels within the physiological range results in cellular redox dysfunction, often termed cellular oxidative stress. Redox dysfunction in turn is at the molecular basis of disease etiology and progression. Accordingly, antioxidant intervention to restore redox homeostasis has been pursued as a therapeutic strategy for cardiovascular disease, cancer, and neurodegenerative disorders among many others. Despite preliminary success in cellular and animal models, redox-based interventions have virtually been ineffective in clinical trials. We propose the fundamental reason for their failure is a flawed delivery approach. Namely, systemic delivery for a geographically local disease limits the effectiveness of the antioxidant. We take a critical look at the literature and evaluate successful and unsuccessful approaches to translation of redox intervention to the clinical arena, including dose, patient selection, and delivery approach. We argue that when interpreting a failed antioxidant-based clinical trial, it is crucial to take into account these variables and importantly, whether the drug had an effect on the redox status. Finally, we propose that local and targeted delivery hold promise to translate redox-based therapies from the bench to the bedside.

Ω-3 index as a prognosis tool in cardiovascular disease

PURPOSE OF REVIEW

In 2004, the 'Ω-3 index' was described as the sum of eicosapentaenoic acid (EPA, 20 : 5 n-3) and docosahexaenoic acid (DHA, 22 : 6 n-3) in red blood cells (RBCs) as an index of coronary heart disease mortality. This review outlines new evidence to support the Ω-3 index as a tool to inform disease prognosis.

RECENT FINDINGS

Recent studies have reported differential metabolism of EPA and DHA. High-dose supplementation with EPA and DHA led to increased levels of RBC DHA that were associated with decreased liver fat. EPA and DHA in RBCs were associated with reduced mortality in a prospective study of patients with cardiac disease; the strongest association was with EPA. A diet containing 9.5-g α-linolenic acid lead to an increase in EPA but not DHA status in middle-aged women.

SUMMARY

Dietary intake or supplementation studies with n-3 fatty acids should include measurement of n-3 status in a standardized way. The Ω-3 index, reflecting EPA and DHA status throughout the body, is convenient and may be appropriate in some cases, but as EPA and DHA assimilate differently in membranes, and have different potency, measurement of individual fatty acid composition in RBCs may be more informative.