The effect of flaxseed dose on circulating concentrations of alpha-linolenic acid and secoisolariciresinol diglucoside derived enterolignans in young, healthy adults

Anti-Oxidant and Anti-Cancer Properties of Flaxseed

Bioactive molecules present in plant products determine their very valuable health-promoting properties. Among the plants, due to these properties, particular attention is paid to the seeds of common flax (Linum usitatissimum L.), which have been used for over 6000 years and are known for their benefits. A review of 117 scientific articles indexed in PubMed/MEDLINE, ScienceDirect, and Wiley Online Library, published between 1997 and 2024, was conducted. These seeds are characterized by a high content of valuable nutrients, such as essential omega-3 fatty acids, including α-linolenic acid (ALA), lignans, isoflavones, phytoestrogens, flavonoids, vitamins, and minerals that influence the digestive system function and have anti-cancer properties. The presence of these bioactive compounds in flaxseeds provide anti-cancer properties.

Investigating the effects of co-supplementation with alpha-linolenic acid and L-carnitine on inflammatory status, oxidative stress, clinical symptoms, mental health and quality of life in women with migraine: a protocol for a randomized, triple-blind, placebo-controlled trial

BACKGROUND

Migraine is a severe neurological disorder that is recognized as one of the most common debilitating diseases worldwide. Although the exact cause of migraine is not known, research suggests that inflammation, oxidative stress, mitochondrial dysfunction, and insufficient nutrients may contribute to its development. Studies indicate that nutrition-based approaches are safer and more cost-effective strategies for managing migraine symptoms compared to medication. In this regard, the impact of nutrition, as a complementary medicine, is largely attributed to that of certain nutrients on inflammation and mitochondrial function. It is hypothesized that alpha-linolenic acid and L-carnitine, which possess anti-inflammatory and antioxidant properties, may be synergically beneficial for migraine patients. Therefore, this study will be conducted to assess the efficacy of alpha-linolenic acid and L-carnitine co-supplementation in patients with migraine.

METHODS

This is a parallel, randomized, triple-blind, placebo-controlled clinical trial, in which 80 women aged 20 to 50 years with migraine will be assigned to receive either intervention group (n = 40) receiving both 1000 mg/day flaxseed oil and 500 mg/day L-carnitine simultaneously for 12 weeks, or control group (n = 40) receiving both 1000 mg/day paraffin oil and 500 mg/day maltodextrin as the placebos for the same duration. The primary outcomes include changes in clinical symptoms of migraine, including frequency, severity, and duration of attacks, serum levels of C-reactive protein (CRP), total antioxidant capacity (TAC), nitric oxide (NO), malondialdehyde (MDA), and superoxide dismutase (SOD). Secondary outcomes include mental health, sleep quality, and quality of life (QOL).

DISCUSSION

In this study, we aim to investigate the potential benefits of combining alpha-linolenic acid and L-carnitine as a treatment option for migraine sufferers. Migraine, characterized by recurrent severe headaches, affects a significant portion of the population and can significantly impact an individual's quality of life. By studying alternative therapies such as alpha-linolenic acid and L-carnitine, researchers hope to expand the range of treatment options available and potentially provide relief to migraine sufferers.

TRIAL REGISTRATION

Iranian Registry of Clinical Trials ( www.irct.ir ) (ID: IRCT20121216011763N57). Registration date: 29 March 2023.

TRIAL STATUS

The protocol is version 1.0 dated December 30, 2023. Recruitment began on July 10, 2023, and is expected to be completed by January 22, 2024.

Untargeted metabolomics and mendelian randomization analysis identify alpha-linolenic acid and linoleic acid as novel biomarkers of perioperative neurocognitive dysfunction

Perioperative neurocognitive dysfunction (PND) occurs in elderly individuals undergoing anesthesia and surgery. To explore the potential molecular mechanisms, we performed right-sided cervical exploratory surgery under sevoflurane anesthesia in 18-month-old male Sprague-Dawley rats. Anxiety-depression-like behaviors and learning memory abilities were assessed using the Open Field Test (OFT) and Novel Object Recognition (NOR). Additionally, the hippocampus was collected one day after surgery for inflammatory factor detection, TUNEL staining, and metabolomics analysis. Mendelian randomization (MR) analyses were subsequently conducted to validate the causal relationships by using a series of GWAS datasets related to representative differential metabolites as exposures and cognitive impairment as endpoints. The results indicated that rats exposed to anesthesia and surgery exhibited poorer cognitive performance, significant elevations in hippocampal inflammatory factors such as IL-1β and TNF-α, and extensive neuronal apoptosis. LC-MS/MS-based untargeted metabolomics identified 19 up-regulated and 32 down-regulated metabolites in the test group, with 6 differential metabolites involved in metabolic pathways enriched according to the KEGG database. ROC analysis revealed a correlation between α-linolenic acid (ALA) and linoleic acid (LA) and the development of PND. Further MR analysis confirmed that ALA was significantly associated with cognitive performance and the risk of depression, while LA was significantly associated with the risk of memory loss. Taken together, our results identified ALA and LA as potentially powerful biomarkers for PND.

Serum bile acid and unsaturated fatty acid profiles of non-alcoholic fatty liver disease in type 2 diabetic patients

BACKGROUND

The understanding of bile acid (BA) and unsaturated fatty acid (UFA) profiles, as well as their dysregulation, remains elusive in individuals with type 2 diabetes mellitus (T2DM) coexisting with non-alcoholic fatty liver disease (NAFLD). Investigating these metabolites could offer valuable insights into the pathophy-siology of NAFLD in T2DM.

AIM

To identify potential metabolite biomarkers capable of distinguishing between NAFLD and T2DM.

METHODS

A training model was developed involving 399 participants, comprising 113 healthy controls (HCs), 134 individuals with T2DM without NAFLD, and 152 individuals with T2DM and NAFLD. External validation encompassed 172 participants. NAFLD patients were divided based on liver fibrosis scores. The analytical approach employed univariate testing, orthogonal partial least squares-discriminant analysis, logistic regression, receiver operating characteristic curve analysis, and decision curve analysis to pinpoint and assess the diagnostic value of serum biomarkers.

RESULTS

Compared to HCs, both T2DM and NAFLD groups exhibited diminished levels of specific BAs. In UFAs, particular acids exhibited a positive correlation with NAFLD risk in T2DM, while the ω-6:ω-3 UFA ratio demonstrated a negative correlation. Levels of α-linolenic acid and γ-linolenic acid were linked to significant liver fibrosis in NAFLD. The validation cohort substantiated the predictive efficacy of these biomarkers for assessing NAFLD risk in T2DM patients.

CONCLUSION

This study underscores the connection between altered BA and UFA profiles and the presence of NAFLD in individuals with T2DM, proposing their potential as biomarkers in the pathogenesis of NAFLD.

Flaxseed oil fraction reverses cardiac remodeling at a molecular level: improves cardiac function, decreases apoptosis, and suppresses miRNA-29b and miRNA 1 gene expression

Flaxseed is an ancient commercial oil that historically has been used as a functional food to lower cholesterol levels. However, despite its longstanding treatment, there is currently a lack of scientific evidence to support its role in the management of cardiac remodeling. This study aimed to address this gap in knowledge by examining the molecular mechanism of standardized flaxseed oil in restoring cardiac remodeling in the heart toxicity vivo model. The oil fraction was purified, and the major components were standardized by qualitative and quantitative analysis. In vivo experimental design was conducted using isoproterenol ISO (85 mg/kg) twice subcutaneously within 24 h between each dose. The rats were treated with flaxseed oil fraction (100 mg/kg orally) and the same dose was used for omega 3 supplement as a positive control group. The GC-MS analysis revealed that α-linolenic acid (24.6%), oleic acid (10.5%), glycerol oleate (9.0%) and 2,3-dihydroxypropyl elaidate (7%) are the major components of oil fraction. Physicochemical analysis indicated that the acidity percentage, saponification, peroxide, and iodine values were 0.43, 188.57, 1.22, and 122.34 respectively. As compared with healthy control, ISO group-induced changes in functional cardiac parameters. After 28-day pretreatment with flaxseed oil, the results indicated an improvement in cardiac function, a decrease in apoptosis, and simultaneous prevention of myocardial fibrosis. The plasma levels of BNP, NT-pro-BNP, endothelin-1, Lp-PLA2, and MMP2, and cTnI and cTn were significantly diminished, while a higher plasma level of Topo 2B was observed. Additionally, miRNA - 1 and 29b were significantly downregulated. These findings provide novel insight into the mechanism of flaxseed oil in restoring cardiac remodeling and support its future application as a cardioprotective against heart diseases.

Investigation of physicochemical and sensory characteristics of low calorie sponge cake made from flaxseed mucilage and flaxseed flour

This research aimed to extract flaxseed mucilage (FM) and investigate its rheological properties (static and dynamic tests) compared with animal oil. In the next stage, the D-optimal design was applied to investigate the effect of FM (0-60%) and FF (0-30%) replacements with animal oil and cake flour, respectively on the sponge cake's physicochemical, textural, and sensory properties. According to the flow behavior test, FM showed Newtonian behavior while animal oil had pseudoplastic behavior. The results of the dynamic test showed with an increase in frequency, the loss modulus (G״) and storage modulus (G') of samples increased. However, G' was higher than G״ in all samples. By replacement of FM and FF, the moisture content, water activity, antioxidant capacity, crumb hardness, and cohesiveness of the samples increased while springiness, crust hardness, and specific volume decreased (P < 0.05). Lightness of samples with replacement of FF decreased (P < 0.05). The overall acceptance score was enhanced with an increase in FM substitution while it was decreased with the replacement of FF (P < 0.05). The amounts of fat, calories, and peroxide values were decreased in sponge cake with the incorporation of FF and FM (P < 0.05). In general, the substitution of FM (60%) and FF (28%) in the cake formulation as an optimized sample to make new products with low-calorie content is possible without significant decreases in product quality.

Phytoestrogens and Health Effects

Phytoestrogens are literally estrogenic substances of plant origin. Although these substances are useful for plants in many aspects, their estrogenic properties are essentially relevant to their predators. As such, phytoestrogens can be considered to be substances potentially dedicated to plant-predator interaction. Therefore, it is not surprising to note that the word phytoestrogen comes from the early discovery of estrogenic effects in grazing animals and humans. Here, several compounds whose activities have been discovered at nutritional concentrations in animals and humans are examined. The substances analyzed belong to several chemical families, i.e., the flavanones, the coumestans, the resorcylic acid lactones, the isoflavones, and the enterolignans. Following their definition and the evocation of their role in plants, their metabolic transformations and bioavailabilities are discussed. A point is then made regarding their health effects, which can either be beneficial or adverse depending on the subject studied, the sex, the age, and the physiological status. Toxicological information is given based on official data. The effects are first presented in humans. Animal models are evoked when no data are available in humans. The effects are presented with a constant reference to doses and plausible exposure.

Platelet Aggregation Inhibition: An Evidence-Based Systematic Review on the Role of Herbs for Primary Prevention Based on Randomized Controlled Trials

BACKGROUND

Platelet aggregation is a crucial mechanism in the progression of atherothrombotic events. This systematic review aims to introduce the plants studied in healthy people as the primary prevention to inhibit platelet aggregation. We also discuss possible mechanisms that are involved in the inhibition of platelet aggregation.

METHODS

A systematic search on the electronic medical databases from 1970 to February 2020 was performed. The selected keywords were: "herb", "plant", "platelet aggregation", "platelet activation", "clinical trial", "randomized" and "controlled".

RESULTS

The result of the initial search was a pool of 136 articles. After initial abstract reviewing, there were 55 relevant articles. Finally, 28 eligible records fulfilled our inclusion criteria to enter the qualitative synthesis process.

CONCLUSION

Out of the 10 plants evaluated in the clinical trials, nine had inhibitory effects on platelet aggregation. Most of the reviewed plants, including tomato (Solanum lycopersicum L), garlic (Allium sativum), kiwifruit (Actinidia deliciosa), cacao (Theobroma cacao), grape (Vitis vinifera), ginkgo (Ginkgo biloba), flaxseed (Linum usitatissimum), sea buckthorn berry (Hippophae), and argan (Argania spinose) could be potential sources for the primary prevention of atherothrombotic events at an appropriate dosage. Finally, we do not consider phytoceuticals as a replacement for the guideline-directed medical treatment. Large randomized double-blind clinical trials are required to evaluate the anti-platelet characteristics of these plants for the adjuvant primary prevention of cardiovascular disease.

The Plasma Oxylipidome Links Smoking Status to Peripheral Artery Disease

Peripheral artery disease (PAD) is prevalent among individuals with a history of tobacco smoking. Although oxidation of lipids may contribute to atherogenesis in vascular disease, enzymatically and nonenzymatically produced oxidized lipids can have varying and contrasting physiological effects. The underlying mechanisms of atherogenic vulnerability can be better elucidated with the recent advances in oxylipidome quantification using HPLC-MS/MS technology. In a randomized, controlled clinical trial, the plasma oxylipidome was analyzed in participants living with PAD by smoking status (n = 98) and in nonsmoking comparators without chronic disease (n = 20). Individuals with PAD had approximately a four-fold higher level of total plasma oxylipins versus the comparator. Cessation of smoking in individuals with PAD was associated with significantly lower levels of linoleic acid-derived TriHOMEs, greater levels of omega-3 fatty acid-derived oxylipins, and greater levels of nonfragmented oxidized phosphatidylcholines (OxPCs). Individuals living with PAD but without a history of smoking, exhibited higher levels of the putative atherogenic fragmented OxPCs versus individuals who currently or previously smoked. These data implicate the plasma oxylipidome in PAD and that smoking cessation is associated with a less inflammatory profile. Furthermore, fragmented OxPCs may play a more significant role in the pathophysiology of PAD in individuals without a history of smoking.

The effect of flaxseed with or without anti-inflammatory diet in patients with rheumatoid arthritis, a randomized controlled trial

PURPOSE

Beneficial effect of long-chain ω-3 fatty acids against symptoms of rheumatoid arthritis (RA) has been indicated in previous studies. We examined the effect of flaxseed and anti-inflammatory diet in patients with RA.

METHODS

The 12-week intervention was performed on 120 patients with RA who were randomized to three groups of flaxseed (30 g/day) plus anti-inflammatory diet (AIF group), flaxseed (30 g/day) plus regular diet (RF group), and roasted wheat (30 g/day) plus regular diet (RW group). Disease Activity Score 28-joints (DAS28), health assessment questionnaire (HAQ) disability and pain, quality of life, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), rheumatoid factor, and anti-cyclic citrullinated peptides (anti-CCP) were measured before and after trial. Analysis was performed using per-protocol and intention-to-treat (ITT) approaches.

RESULTS

One hundred and two patients completed the protocol. Flaxseed decreased DAS28 in RF group compared to RW (- 0.87 ± 1.11 vs. - 0.24 ± 0.78; P = 0.014). Pain severity (P ≤ 0.001), morning stiffness (P < 0.05), and disease feeling (P < 0.01) decreased significantly in AIF and RF groups. HAQ disability and quality of life measurements improved in all 3 groups, with a greater extent in AIF and RF groups (P < 0.001) compared to RW. Between-group differences were significant for DAS28, pain scores, and physical and mental health variables. ESR, CRP, anti-CCP, and rheumatoid factor were not different between groups. Results of ITT analysis did not cause much difference.

CONCLUSIONS

In conclusion, flaxseed may be used as a helpful adjuvant therapy for patients with RA. Calls are open for examining the effect of anti-inflammatory diet on RA symptoms.

TRIAL REGISTRATION NUMBER

Registered at irct.ir as IRCT20190923044858N1, February 6, 2020.

The review of alpha-linolenic acid: Sources, metabolism, and pharmacology

α-linolenic acid (ALA, 18:3n-3) is a carboxylic acid composed of 18 carbon atoms and three cis double bonds, and is an essential fatty acid indispensable to the human body. This study aims to systematically review related studies on the dietary sources, metabolism, and pharmacological effects of ALA. Information on ALA was collected from the internet database PubMed, Elsevier, ResearchGate, Web of Science, Wiley Online Library, and Europe PMC using a combination of keywords including "pharmacology," "metabolism," "sources." The following findings are mainly contained. (a) ALA can only be ingested from food and then converted into eicosapentaenoic acid and docosahexaenoic acid in the body. (b) This conversion process is relatively limited and affected by many factors such as dose, gender, and disease. (c) Pharmacological research shows that ALA has the anti-metabolic syndrome, anticancer, antiinflammatory, anti-oxidant, anti-obesity, neuroprotection, and regulation of the intestinal flora properties. (d) There are the most studies that prove ALA has anti-metabolic syndrome effects, including experimental studies and clinical trials. (e) The therapeutic effect of ALA will be affected by the dosage. In short, ALA is expected to treat many diseases, but further high quality studies are needed to firmly establish the clinical efficacy of ALA.

Combination therapy of flaxseed and hesperidin enhances the effectiveness of lifestyle modification in cardiovascular risk control in prediabetes: a randomized controlled trial

BACKGROUND

Regarding the increasing prevalence of cardiometabolic abnormalities, and its association with non-communicable chronic diseases, providing preventive and therapeutic strategies is a priority. A randomized placebo-controlled study was conducted to assess the effects of combination therapy of milled brown flaxseed and hesperidin during lifestyle intervention on controlling cardiovascular risk in prediabetes.

METHODS

A total of forty-eight subjects were randomly assigned to receive lifestyle intervention plus combination therapy of brown flaxseed (30 g milled) and hesperidin (two 500 mg capsules) or lifestyle modification alone for 12 weeks. Changes from baseline in anthropometric measures, lipid profile and atherogenic indices, glucose homeostasis parameters, and inflammatory biomarkers was assessed as a primary end point.

RESULTS

Anthropometric data comparison between the two groups showed a significant reduction in weight (p = 0.048). Waist circumference reduction was about twice that of the control group (- 6.75 cm vs - 3.57 cm), but this difference was not statistically significant. Comparison of blood pressure changes throughout the study indicated a greater reduction in blood pressure in the intervention group rather than control group (- 5.66 vs. - 1.56 mmHg, P = 0.049). Improvements of lipid profile and atherogenic indices, glucose homeostasis parameters, and inflammatory biomarkers in flaxseed-hesperidin group was significantly more than the control group after 12 weeks of intervention (p < 0.05).

CONCLUSION

Our results indicate that co-administration of flaxseed and hesperidin as an adjunct to lifestyle modification program is more effective than lifestyle modification alone in the metabolic abnormalities remission of prediabetic patients.

TRIAL REGISTRATION

 The trial was registered with ClinicalTrials.gov, number NCT03737422. Registered 11 November 2018. Retrospectively registered, https://clinicaltrials.gov/ct2/results?cond=&term=NCT03737422&cntry=&state=&city=&dist= .

Flaxseed for Health and Disease: Review of Clinical Trials

BACKGROUND

Flaxseed (Linum usitatissimum) is an oil-based seed that contains high amounts of alpha-linolenic acid, linoleic acid, lignans, fiber and many other bioactive components which is suggested for a healthier life. Nowadays, flaxseed is known as a remarkable functional food with different health benefits for humans and protects against cardiovascular disease, diabetes, dyslipidemia, obesity and altogether metabolic syndrome.

METHODS

To review the bioactive components of flaxseed and their potential health effects, PubMed and Scopus were searched from commencement to July 2019. Keywords including: "flaxseed", "Linum usitatissimum", "metabolic syndrome", "obesity", "inflammation", "insulin resistance", "diabetes", "hyperlipidemia" and "menopause" were searched in the databases with varying combinations.

CONCLUSION

Consumption of flaxseed in different forms has valuable effects and protects against cardiovascular disease, hypertension, diabetes, dyslipidemia, inflammation and some other complications. Flaxseed can serve as a promising candidate for the management of metabolic syndrome to control blood lipid levels, fasting blood sugar, insulin resistance, body weight, waist circumference, body mass and blood pressure.

Genetic Variation in Steroid and Xenobiotic Metabolizing Pathways and Enterolactone Excretion Before and After Flaxseed Intervention in African American and European American Women

BACKGROUND

Metabolism and excretion of the phytoestrogen enterolactone (ENL), which has been associated with breast cancer risk, may be affected by variation in steroid hormone and xenobiotic-metabolizing genes.

METHODS

We conducted a randomized, crossover flaxseed intervention study in 252 healthy, postmenopausal women [137 European ancestry (EA) and 115 African ancestry (AA)] from western New York. Participants were randomly assigned to maintain usual diet or consume 10 g/day ground flaxseed for 6 weeks. After a 2-month washout period, participants crossed over to the other diet condition for an additional 6 weeks. Urinary ENL excretion was measured by gas chromatography-mass spectrometry and 70 polymorphisms in 29 genes related to steroid hormone and xenobiotic metabolism were genotyped. Mixed additive genetic models were constructed to examine association of genetic variation with urinary ENL excretion at baseline and after the flaxseed intervention.

RESULTS

SNPs in several genes were nominally (P < 0.05) associated with ENL excretion at baseline and/or after intervention: ESR1, CYP1B1, COMT, CYP3A5, ARPC1A, BCL2L11, SHBG, SLCO1B1, and ZKSCAN5. A greater number of SNPs were associated among AA women than among EA women, and no SNPs were associated in both races. No SNP-ENL associations were statistically significant after correction for multiple comparisons.

CONCLUSIONS

Variation in several genes related to steroid hormone metabolism was associated with lignan excretion at baseline and/or after flaxseed intervention among postmenopausal women.

IMPACT

These findings may contribute to our understanding of the differences observed in urinary ENL excretion among AA and EA women and thus hormone-related breast cancer risk.

Impact of lignans in oilseed mix on gut microbiome composition and enterolignan production in younger healthy and premenopausal women: an in vitro pilot study

BACKGROUND

Dietary lignans belong to the group of phytoestrogens together with coumestans, stilbenes and isoflavones, and themselves do not exhibit oestrogen-like properties. Nonetheless, the gut microbiota converts them into enterolignans, which show chemical similarity to the human oestrogen molecule. One of the richest dietary sources of lignans are oilseeds, including flaxseed. The aim of this pilot study was to determine the concentration of the main dietary lignans in an oilseed mix, and explore the gut microbiota-dependent production of enterolignans for oestrogen substitution in young and premenopausal women. The oilseed mix was fermented in a pH-controlled batch culture system inoculated with women's faecal samples. The lignan content and enterolignan production were measured by ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), and the faecal-derived microbial communities were profiled by 16S rRNA gene-based next-generation sequencing.

RESULTS

In vitro batch culture fermentation of faecal samples inoculated with oilseed mix for 24 h resulted in a substantial increase in enterolactone production in younger women and an increase in enterodiol in the premenopausal group. As for the gut microbiota, different baseline profiles were observed as well as different temporal dynamics, mainly related to Clostridiaceae, and Klebsiella and Collinsella spp.

CONCLUSIONS

Despite the small sample size, our pilot study revealed that lignan-rich oilseeds could strongly influence the faecal microbiota of both younger and premenopausal females, leading to a different enterolignan profile being produced. Further studies in larger cohorts are needed to evaluate the long-term effects of lignan-rich diets on the gut microbiota and find out how enterolactone-producing bacterial species could be increased. Diets rich in lignans could potentially serve as a safe supplement of oestrogen analogues to meet the cellular needs of endogenous oestrogen and deliver numerous health benefits, provided that the premenopausal woman microbiota is capable of converting dietary precursors into enterolignans.

Fermentation of flaxseed cake increases its nutritional value and utilization in ducklings

Flaxseed cake (FSC) is a potential alternative feed source in poultry. However, cyanogenetic glycosides limit its widespread use in feed. In this study, we optimized the parameters of fermentation by Aspergillus niger and Candida utilis and compared the growth performance, serum lipid parameters, and organ indexes of Cherry Valley duckling feed with unfermented FSC (UFSC) or fermented FSC (FFSC). A total of 420 one-day-old male Cherry Valley ducklings were randomly assigned into a 1 plus 2 × 3 factorial design including 2 different FSC resources (UFSC and FFSC) at 3 levels (50, 100, or 150 g/kg) for 3 wk. Each treatment group included 6 pens with 10 ducklings per pen. The hydrocyanic acid (HCN) level was reduced under the following conditions: 1:0.8 FSC:water (w:v), inoculum ratio of 1 mL:1 mL, 30°C, and 60 h. FFSC had higher crude protein (CP) and calcium (Ca) levels and lower HCN levels compared with UFSC (P < 0.05). There was no interactive effect between FSC sources and levels on growth performance. Final body weight (FBW), average daily feed intake (ADFI), and average daily gain (ADG) in UFSC groups and ADFI in FFSC groups decreased linearly with increasing FSC levels (P < 0.01). There were no differences in FBW, ADG, or feed:gain ratio (F/G) among FFSC groups, and all 7 FSC groups had no differences in the F/G ratio (P > 0.05). Dietary FSC supplementation decreased triglyceride (TG) (P < 0.01), total cholesterol (TC) (P < 0.01), high-density lipoprotein (HDL) (P = 0.01), and low-density lipoprotein (LDL) (P < 0.01). No interactive effect between FSC levels and sources was observed for serum TG, TC, HDL, or LDL. Ducklings fed FFSC had lower TG (P < 0.01), TC (P = 0.05), and LDL (P < 0.01) levels compared with ducklings fed UFSC. The 150 g/kg FFSC group had the lowest TG, TC, HDL, and LDL levels among all 7 groups. Flaxseed cake supplementation decreased the relative weight of the left breast, but FFSC increased the relative weight of the gizzard compared with UFSC. In conclusion, fermentation could increase the nutritional value and usage of FSC in ducklings.

Urolithin A gains in antiproliferative capacity by reducing the glycolytic potential via the p53/TIGAR axis in colon cancer cells

Polyphenols have shown promising bioactivity in experimental in vitro and in vivo models for cancer chemoprevention. However, consumed orally, they are often transformed by gut microbes into new active principles with so far incompletely deciphered molecular mechanisms. Here, enterolacton, S-equol and urolithin A as representatives of metabolites of lignans, isoflavones and ellagitannins, respectively, were examined for their impact on HCT116 colon cancer cell growth, cooperativity with oxaliplatin and p53 dependency in vitro. Whereas enterolacton and S-equol (≤60 µM) did not elicit growth inhibition or positive cooperativity with oxaliplatin, urolithin A showed an IC50 value of 19 µM (72 h) and synergism with oxaliplatin. Urolithin A induced p53 stabilization and p53 target gene expression, and absence of p53 significantly dampened the antiproliferative effect of urolithin A (IC50(p53-/-) = 38 µM). P53 was dispensable for the G2/M arrest in HCT116 cells but required for induction of a senescence-like phenotype upon long-term exposure and for the observed synergism with oxaliplatin. Moreover, extracellular flux analyses and knockdown approaches uncovered a reduced glycolytic potential via the p53/TIGAR axis which was linked to the higher susceptibility of wildtype cells to urolithin A. Overall, the p53 status turned out to be an important determinant for the potential benefit of dietary ellagitannins in cancer chemoprevention or use in adjuvant therapy.

Dietary Flaxseed as a Strategy for Improving Human Health

Flaxseed is a rich source of the omega-3 fatty acid, alpha linolenic acid, the lignan secoisolariciresinol diglucoside and fiber. These compounds provide bioactivity of value to the health of animals and humans through their anti-inflammatory action, anti-oxidative capacity and lipid modulating properties. The characteristics of ingesting flaxseed or its bioactive components are discussed in this article. The benefits of administering flaxseed or the individual bioactive components on health and disease are also discussed in this review. Specifically, the current evidence on the benefits or limitations of dietary flaxseed in a variety of cardiovascular diseases, cancer, gastro-intestinal health and brain development and function, as well as hormonal status in menopausal women, are comprehensive topics for discussion.

In vitro effect of flaxseed oil and α-linolenic acid against the toxicity of lipopolysaccharide (LPS) to human umbilical vein endothelial cells

Consumption of α-linolenic acid (ALA)-rich flaxseed oil is a possible way to supplement ω-3 polyunsaturated fatty acids, but the beneficial effects to cardiovascular systems are still controversial. In this study, human umbilical vein endothelial cells (HUVECs) treated with 100 ng/mL lipopolysaccharide (LPS) were used as the in vitro model and the potential beneficial effects of well-characterized flaxseed oil and ALA were studied. Exposure of HUVECs to LPS for 24 h significantly promoted inflammatory response as release of interleukin 6 (IL-6), soluble intercellular cell adhesion molecule-1 (sICAM-1) and soluble vascular cell adhesion molecule 1 (sVCAM-1) as well as adhesion of THP-1 monocytes, but did not induce cytotoxicity or oxidative stress. ALA, but not flaxseed oil, significantly reduced LPS-induced release of sICAM-1 and sVCAM-1, without effect on THP-1 adhesion. No radical scavenging activity was observed after flaxseed oil or ALA exposure. Rather, ALA at high concentrations promoted intracellular superoxide associated with damages to lysosomes, which was not observed in flaxseed oil exposed cells. These results indicated that ALA at high concentrations could inhibit inflammatory responses in LPS-treated HUVECs in vitro but might also promote a modest effect in cytotoxicity and oxidative stress.

Flaxseed: its bioactive components and their cardiovascular benefits

Cardiovascular disease remains the leading cause of mortality and morbidity worldwide. The inclusion of functional foods and natural health products in the diet are gaining increasing recognition as integral components of lifestyle changes in the fight against cardiovascular disease. Several preclinical and clinical studies have shown the beneficial cardiovascular effects of dietary supplementation with flaxseed. The cardiovascular effects of dietary flaxseed have included an antihypertensive action, antiatherogenic effects, a lowering of cholesterol, an anti-inflammatory action, and an inhibition of arrhythmias. Its enrichment in the ω-3 fatty acid α-linolenic acid and the antioxidant lignan secoisolariciresinol diglucoside as well as its high fiber content have been implicated primarily in these beneficial cardiovascular actions. Although not as well recognized, flaxseed is also composed of other potential bioactive compounds such as proteins, cyclolinopeptides, and cyanogenic glycosides, which may also produce biological actions. These compounds could also be responsible for the cardiovascular effects of flaxseed. This article will not only summarize the cardiovascular effects of dietary supplementation with flaxseed but also review its bioactive compounds in terms of their properties, biological effects, and proposed mechanisms of action. It will also discuss promising research directions for the future to identify additional health-related benefits of dietary flaxseed.

Phytoestrogen Metabolism by Adult Human Gut Microbiota

Phytoestrogens are plant-derived polyphenols with a structure similar to human estrogens. The three main groups of phytoestrogens, isoflavones, ellagitannins, and lignans, are transformed into equol, urolithins, and enterolignans, respectively, by bacteria. These metabolites have more estrogenic/antiestrogenic and antioxidant activities than their precursors, and they are more bioavailable. The aim of this study was to analyze the metabolism of isoflavones, lignans and ellagitannins by gut microbiota, and to study the possible correlation in the metabolism of these three groups of phytoestrogens. In vitro fermentation experiments were performed with feces samples from 14 healthy adult volunteers, and metabolite formation was measured by HPLC-PAD and HPLC-ESI/MS. Only the microbiota of one subject produced equol, while most of them showed production of O-desmethylangolensin (O-DMA). Significant inter-subject differences were observed in the metabolism of dihydrodaidzein and dihydrogenistein, while the glucoside isoflavones and their aglycones showed less variability, except for glycitin. Most subjects produced urolithins M-5 and E. Urolithin D was not detected, while uroltithin B was found in half of the individuals analyzed, and urolithins A and C were detected in two and four subjects, respectively. Enterolactone was found in all subjects, while enterodiol only appeared in five. Isoflavone metabolism could be correlated with the metabolism of lignans and ellagitannins. However, the metabolism of ellagitannins and lignans could not be correlated. This the first study where the metabolism of the three groups together of phytoestrogen, isoflavones, lignans, and ellagitannins by gut microbiota is analyzed.