Furan fatty acid as an anti-inflammatory component from the green-lipped mussel Perna canaliculus

The emerging significance of furan fatty acids in food, nutrition, and potential therapeutic use

The emerging significance of furan fatty acids (FuFAs) is explored at the intersection of food, chemistry, nutrition, and therapeutics. FuFAs, with a distinctive furan ring incorporated into fatty acyl chains, are minor yet bioactive constituents of dietary lipids known for their unique chemical properties. This review examines FuFA biosynthesis in various organisms, highlighting their occurrence in food products. We also address the challenges of FuFA instability, which influence their availability and impact on food science. The chemical synthesis of FuFAs is reviewed, paving the way for future animal and human studies. FuFAs exhibit potent antioxidant and anti-inflammatory effects, with growing evidence of their role in metabolic health. Recent research suggests that FuFAs may extend benefits beyond omega-3 fatty acids in promoting cardiovascular and metabolic health. By consolidating current knowledge and identifying gaps, this review sets the stage for future research to harness the therapeutic potential of FuFAs.

Furan fatty acids supplementation in obese mice reverses hepatic steatosis and protects against cartilage degradation

Obesity is a major global health problem associated with numerous metabolic dysfunctions, an increased risk of developing Metabolic Associated Steatotic Liver Disease (MASLD) and osteoarthritis. Recently, we demonstrated that in Diet-induced-Obesity (DIO) mouse model, preventive furan fatty acids (FuFA-F2) supplementation, a natural compounds found in many foods, reduced the onset of metabolic disorders and increased muscle mass. Here, we aimed to determine whether a short FuFA-F2 supplementation is capable of providing beneficial health effects in obese mice, notably by reversing metabolic disorders and limiting cartilage degradation. 6-month-old obese C57Bl/6 J mice were fed for four additional weeks on a high-fat and high-sucrose (HFHS) diet, supplemented or not with FuFA-F2 (40 mg/day/kg of body weight). Liver triglyceride content and histologic analysis revealed that 4 weeks of FuFA-F2 supplementation fully reversed hepatic steatosis in obese mice. Liver RNA-sequencing analysis highlighted that FuFA-F2 partly reversed the gene expression signature induced by the HFHS diet and favorably changed the expression of many genes known to be involved in the development of hepatic steatosis such as Pcsk9, Stard4, Insig1 and Sulf2. We also found that FuFA-F2 supplementation increased skeletal muscle mass and protected against cartilage degradation and synovitis induced by obesity. Our findings demonstrated that FuFA-F2 supplementation for 4 weeks in obese mice was enough to reverse the development of MASLD, promote an increase in skeletal muscle mass and protect against cartilage degradation induced by the HFHS diet. This study highlights that nutritional supplementation with FuFA-F2 could be an effective approach to treat obesity-related disorders.

Omega-3 Fatty Acids, Furan Fatty Acids, and Hydroxy Fatty Acid Esters: Dietary Bioactive Lipids with Potential Benefits for MAFLD and Liver Health

Metabolic dysfunction-associated fatty liver disease (MAFLD) is the most common form of chronic liver disease, for which only resmetirom has recently received FDA approval. Prevention is crucial, as it can help manage and potentially reverse the progression of MAFLD to more severe stages. Omega-3 fatty acids, which are a type of polyunsaturated fatty acid (PUFA), have numerous beneficial effects in health and disease, including liver disease. Other bioactive lipids, such as furanic fatty acids (FuFA) and hydroxy fatty acid esters (FAHFA), have also demonstrated several benefits on relevant markers of liver dysfunction in animal and cell models. However, the effects of FAHFAs on hepatic steatosis are inconsistent, and studies on the impact of FuFAs in MAFLD are scarce. Further and more extensive research is required to better understand their role in liver health. The aim of this narrative review is to provide a brief overview of the potential effects of omega-3 fatty acids and other bioactive lipids, such as FuFAs and FAHFAs, on liver disease, with a focus on MAFLD.

Mussel oil is superior to fish oil in preventing atherosclerosis of ApoE-/- mice

Objectives

The present study aimed to explore the preventive effect of mussel oil (MO) on atherosclerosis and the potential mechanism in apolipoprotein E-null (ApoE-/-) mice.

Methods

ApoE-/- mice were fed with a high-fat and high-cholesterol chow and given corn oil (CO), fish oil (FO), MO, or aspirin (ASP, dissolved in CO) by gavage for 12  weeks. The total n-3 polyunsaturated fatty acids (PUFAs) in MO (51.01%) and FO (46.82%) were comparable (mainly C22:6n-3 and C20:5n-3). Wild-type mice were fed with a normal chow and given equivalent CO as health control (CON).

Results

Compared with the CON group, obvious atherosclerotic plaque appeared at aorta and aortic sinus in the CO group. Compared with the CO group, MO but not FO had a significantly smaller atherosclerotic plaque area in the aorta. The aortic atherosclerotic plaque area was comparable in the MO, CON, and ASP groups. The MO group had a significantly smaller atherosclerotic plaque area, lower lipid deposition, lower contents of smooth muscle cell (SMC), and slightly lower contents of macrophage at the aortic sinus than the FO group. Serum concentrations of IL-1β, NF-κB, and VCAM-1 were comparable in the MO and FO groups and were significantly lower than the CO group. Compared with the CO group, the MO group but not FO group had significantly lower aortic protein levels of p65NF-κB, p38MAPK, and VCAM-1. The aortic protein levels of p-p65NF-κB and p-p38MAPK were significantly lower in the MO group than the FO group.

Conclusion

In conclusion, MO is more potent than FO in preventing atherosclerosis, and the possible mechanism may be by downregulating p38MAPK/NF-κB signaling pathway, decreasing VCAM-1 and macrophage, and inhibiting proliferation and migration of SMC.

Differential contributions of the gut microbiota and metabolome to pathomechanisms in ulcerative colitis: an in vitro analysis

The gut microbiota has been implicated in onset and progression of ulcerative colitis (UC). Here, we assess potential causal involvement of the microbiota and -associated fecal water (FW) metabolome in altering key functional parameters of the colonic epithelium. Fecal samples were collected from N = 51 healthy controls (HC), N = 36 patients with active UC (UC-A), and N = 41 subjects in remission N = 41 (UC-R). Using in vitro incubation experiments, the FW metabolome's impact on butyrate oxidation rates/gene expression and cell death (cytotoxicity) of HT-29 cells, cytokine production by PBMC, and barrier integrity of Caco2 monolayers was evaluated. The FW metabolome from patients and individuals hosting the Bacteroides 2 (Bact2) enterotype (69% of UC-A, 31% of UC-R, 3% of HC), characterized by lower levels of median- and short-chain fatty acids and furan compounds, left butyrate oxidation rates unaltered but affected associated gene expression profiles. UC patients/Bact2-carriers' FW lowered PBMC IL-8 production and increased IL-1β production. Patients' FW increased cytotoxicity, associated with sulfide compound levels. Bact2 carriers' FW, displaying higher levels of bile acids, lowered barrier function upon incubation of monolayers. The FW metabolome of patients and individuals hosting a dysbiotic microbiota could contribute to the disruption of functional processes of the colonic epithelium as observed in UC.

A randomised, double-blinded, controlled trial to determine the efficacy of combined therapy of oclacitinib and marine oil extract PCSO-524 in dogs with atopic dermatitis

BACKGROUND

Polyunsaturated fatty acids (PUFA) can be beneficial in the management of canine atopic dermatitis (cAD). A commercial product PCSO-524 containing PUFA has demonstrated anti-inflammatory effects in dogs.

HYPOTHESIS/OBJECTIVES

To evaluate the efficacy of PCSO-524, in combination with oclacitinib in dogs with cAD.

ANIMALS

Seventeen client-owned dogs with cAD.

MATERIALS AND METHODS

A randomised, double-blinded, controlled trial. All dogs were treated with oclacitinib (0.4-0.6 mg/kg) twice a day for 14 days, then once a day until Day (D)42. They were randomly divided into two groups: PCSO-524 (n = 9) and sunflower oil (n = 8). Clinical status was assessed by Canine Atopic Dermatitis Extent and Severity Index, 4th iteration (CADESI-04) and pruritus Visual Analog Scale (pVAS) at baseline (D0), D14, D28 and D42. Trans epidermal water loss (TEWL) was measured at the same time points.

RESULTS

CADESI scores decreased significantly after treatment and there was a significant difference between the PCSO-524 and the control group at D28 (p = 0.04) and D42 (p = 0.03). The PCSO-524 group also demonstrated a significantly decreased pVAS on D28 and D42 (p < 0.001 and p < 0.001) compared to D0, while significant differences were observed in the control group at D14 and D28 (p < 0.01 and p = 0.04) and not at D42 (p = 0.12). The mean TEWL showed a significant decrease at D28 and D42 in the PCSO-524 group, compared to the control group (p = 0.002 and p < 0.001).

CONCLUSIONS AND CLINICAL RELEVANCE

The combination of PCSO-524 and oclacitinib may help to alleviate the rebound effect that occurs when tapering down the dosage of oclacitinib, as compared to using oclacitinib alone for the management of cAD.

Effects of lipid extract from blue mussel (Mytilus edulis) on gut microbiota, and its relationship with glycemic traits in type 2 diabetes mellitus patients: a double-blind randomized controlled trial

Studies have shown that blue mussel lipid extract (BMLE) can improve the glycemic traits, inflammatory cytokines, and lipid profile of patients with type 2 diabetes mellitus (T2DM) in China. Gut microbiota is closely related to T2DM. This study aims to explore whether BMLE can improve the glycemic status of T2DM patients by regulating gut microbiota in a 60-day double-blind randomized controlled trial. A total of 133 T2DM subjects were randomized into BMLE (n = 44), fish oil (FO) (n = 44), and corn oil (CO) (n = 45) groups. The participants were asked to take two corresponding oil capsules (0.8 g per capsule each) every day. The faecal microbiota, glycemic traits, and other cardiometabolic factors were analyzed at baseline and endpoint. The α diversity estimators of Ace and Chao1 decreased significantly in all three groups, but there was no significant difference between the groups. Eight bacteria decreased significantly in the BMLE group but not in the FO and CO groups: unclassified_Clostridia_UCG_014, unclassified_Bacteroidia, Erysipelotrichaceae, and uncultured_Ruminococcaceae_bacterium at the family level and unclassified_Bacteroidia, uncultured_Ruminococcaceae_bacterium, unclassified_Clostridia_UCG_014, and Turicibacter at genus level. In the BMLE group, the change in the relative abundance of Erysipelotrichaceae was positively correlated with the changes in the homeostatic model assessment of insulin resistance (HOMA-IR) (r = 0.454, p < 0.01) and fasting insulin (r = 0.414, p < 0.01). The change in the relative abundance of Turicibacter was positively correlated with the changes in HOMA-IR (r = 0.431, p < 0.01), fasting insulin (r = 0.414, p < 0.01), total cholesterol (TC) (r = 0.358, p < 0.05), and triacylglycerol (TG) (r = 0.393 p = 0.013). In conclusion, BMLE might improve glycemic traits by modulating gut microbiota in T2DM patients.

Furan fatty acid extracted from Hevea brasiliensis latex increases muscle mass in mice

Skeletal muscle is essential for locomotion and plays a crucial role in energy homeostasis. It is regulated by nutrition, genetic factors, physical activity and hormones. Furan fatty acids (FuFAs) are minor fatty acids present in small quantities in food from plants and animals origin. Recently, we showed that a preventive nutritional supplementation with furan fatty acid in a DIO mouse model reduces metabolic disorders. The present study was designed to determine the influence of FuFA-F2 extracted from Hevea brasiliensis latex on skeletal muscle phenotype. In C2C12 myotubes we found that FuFA-F2 whatever the concentration used increased protein content. We revealed that in C2C12 myotubes FuFA-F2 (10 µM) increases protein synthesis as shown by the stimulation of mTOR phosphorylation. Next, to confirm in vivo our results C57Bl6 mice were supplemented by oral gavage with vehicle or FuFA-F2 (20 mg/kg) for 3 and a half weeks. We found that mice supplemented with FuFA-F2 had a greater lean mass than the control mice. In line with this observation, we revealed that FuFA-F2 increased muscle mass and promoted more oxidative muscle metabolism in mice as attested by cytochrome c oxidase activity. In conclusion, we demonstrated that FuFA-F2 stimulates muscle anabolism in mice in vitro and in vivo, mimicking in part physical activity. This study highlights that in vivo FuFA-F2 may have health benefits by increasing muscle mass and oxidative metabolism.

Furan fatty acid metabolite CMPF is associated with lower risk of type 2 diabetes, but not chronic kidney disease: a longitudinal population-based cohort study

BACKGROUND

Furan fatty acid metabolite 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid (CMPF) is a strong biomarker of fish and n-3 polyunsaturated fatty acid (PUFA) intake. The relationship of CMPF with human health has been controversial, especially for type 2 diabetes and chronic kidney disease.

OBJECTIVE

We performed a prospective cohort study to examine the association of serum CMPF with incident type 2 diabetes and chronic kidney disease.

METHODS

In the Guangzhou Nutrition and Health Study, during a median follow-up of 8.8 y, we used a multivariable-adjusted Poisson regression model to investigate the association of baseline serum CMPF with the incidence of type 2 diabetes (1470 participants and 170 incident cases) and chronic kidney disease (1436 participants and 112 incident cases). We also examined the association of serial measures of serum CMPF with glycemic and renal function biomarkers. Mediation analysis was also performed to examine the contribution of CMPF in the association between marine n-3 PUFAs and risk of type 2 diabetes or chronic kidney disease.

RESULTS

Each standard deviation increase in baseline serum CMPF was associated with an 18% lower risk of type 2 diabetes (relative risk: 0.82, 95% confidence interval [CI]: 0.68, 0.99) but was not associated with chronic kidney disease (relative risk: 0.95; 95% CI: 0.77-1.16). Correlation analyses of CMPF with glycemic and renal function biomarkers showed similar results. Mediation analysis suggested that serum CMPF contributed to the inverse association between erythrocyte marine n-3 PUFAs and incident type 2 diabetes (proportion mediated 37%, P-mediation = 0.022).

CONCLUSIONS

Our findings suggest that serum CMPF was associated with a lower risk of type 2 diabetes but not chronic kidney disease. This study also suggests that CMPF may be a functional metabolite underlying the protective relationship between marine n-3 PUFA intake and type 2 diabetes.

Preventive nutritional supplementation with furan fatty acid in a DIO mouse model increases muscle mass and reduces metabolic disorders

The increase in obesity has become a major global health problem and is associated with numerous metabolic dysfunctions. Furan fatty acids (FuFAs) are minor lipids present in our diet. Recently we showed that FuFA-F2 extracted from Hevea brasiliensis latex stimulates muscle anabolism in mice in vitro and in vivo, mimicking in part physical activity. While skeletal muscle is essential for energy metabolism and is the predominant site of insulin-mediated glucose uptake in the post prandial state, our results suggested that FuFA-F2 could have favorable effects against obesity. The aim of this work was therefore to study whether a preventive nutritional supplementation with FuFA-F2 (40 mg or 110 mg/day/kg of body weight) in a diet-induced obesity (DIO) mouse model may have beneficial effects against obesity and liver and skeletal muscle metabolic dysfunction. We showed that 12 weeks of FuFA-F2 supplementation in DIO mice decreased fat mass, increased lean mass and restored normal energy expenditure. In addition, we found that FuFA-F2 improved insulin sensitivity. We revealed that FuFA-F2 increased muscle mass but had no effect on mitochondrial function and oxidative stress in skeletal muscle. Furthermore, we observed that FuFA-F2 supplementation reduced liver steatosis without impact on mitochondrial function and oxidative stress in liver. Our findings demonstrated for the first time that a preventive nutritional supplementation with a furan fatty acid in DIO mice reduced metabolic disorders and was able to mimic partly the positive effects of physical activity. This study highlights that nutritional FuFA-F2 supplementation could be an effective approach to treat obesity and metabolic syndrome.

Targeting the Inflammatory Hallmarks of Obesity-Associated Osteoarthritis: Towards Nutraceutical-Oriented Preventive and Complementary Therapeutic Strategies Based on n-3 Polyunsaturated Fatty Acids

Obesity (Ob), which has dramatically increased in the last decade, is one of the main risk factors that contribute to the incidence and progression of osteoarthritis (OA). Targeting the characteristics of obesity-associated osteoarthritis (ObOA) may offer new chances for precision medicine strategies in this patient cohort. First, this review outlines how the medical perspective of ObOA has shifted from a focus on biomechanics to the significant contribution of inflammation, mainly mediated by changes in the adipose tissue metabolism through the release of adipokines and the modification of fatty acid (FA) compositions in joint tissues. Preclinical and clinical studies on n-3 polyunsaturated FAs (PUFAs) are critically reviewed to outline the strengths and weaknesses of n-3 PUFAs' role in alleviating inflammatory, catabolic and painful processes. Emphasis is placed on potential preventive and therapeutic nutritional strategies based on n-3 PUFAs, with a focus on ObOA patients who could specifically benefit from reformulating the dietary composition of FAs towards a protective phenotype. Finally, tissue engineering approaches that involve the delivery of n-3 PUFAs directly into the joint are explored to address the perspectives and current limitations, such as safety and stability issues, for implementing preventive and therapeutic strategies based on dietary compounds in ObOA patients.

Lipid extract from blue mussel (Mytilus edulis) improves glycemic traits in Chinese type 2 diabetic mellitus patients: a double-blind randomized controlled trial

BACKGROUND

Studies have shown that blue mussel lipid extract (BMLE) has strong anti-inflammatory activity in both rheumatoid arthritis patients and animal arthritis models. Chronic inflammation was closely related to type 2 diabetes mellitus (T2DM). Though the beneficial effects cannot be completely attributed to n-3 polyunsaturated fatty acids, the aim of this study was to investigate whether BMLE can improve glycemic traits of T2DM patients.

METHOD

In a double-blind randomized controlled trial, 133 Chinese T2DM participants were randomized to either fish oil (FO, n = 44), BMLE (n = 44), or corn oil (CO, n = 45) groups for 60 days. The participants were asked to take the corresponding oil capsules (two capsules per day, 0.8 g per capsule), which provided 1.6 g day^-1 of FO (29.9% eicosapentaenoic acid + 20.4% docosahexaenoic acid), BMLE (20.7% eicosapentaenoic acid + 26.7% docosahexaenoic acid), or CO (53.5% linoleic acid).

RESULTS

The fasting serum concentration of insulin (P = 0.005) and the homeostasis model of insulin resistance (P = 0.026) were significantly decreased in the BMLE group, whereas no significant change was found in the FO or CO groups. There was no significant difference between groups on serum glycosylated hemoglobin. Tumor necrosis factor-α was significantly decreased in the BMLE group (P = 0.003), but not in the FO or CO groups. A significant decrease of interleukin-1β was observed in the BMLE and CO groups (P = 0.004 and P = 0.011 respectively), but not in the FO group. The total cholesterol was significantly decreased in the BMLE and CO groups (P < 0.001 and P < 0.001 respectively), but not in the FO group. Triacylglycerol was significantly decreased in the BMLE group (P = 0.007), but not in the FO or CO groups. High-density lipoprotein cholesterol was significantly lower in the BMLE and CO groups than in the FO group (P = 0.003).

CONCLUSION

Blue mussel lipid supplements improved glycemic traits, inflammatory cytokines, and lipids profile in Chinese T2DM patients (Chinese Clinical Trial Registration number: ChiCTR1900025617). © 2022 Society of Chemical Industry.

Geometrical and positional isomers of unsaturated furan fatty acids in food

Furan fatty acids (FuFA) are important antioxidants found in low concentrations in many types of food. In addition to conventional FuFA which normally feature saturated carboxyalkyl and alkyl chains, a few previous studies indicated the FuFA co-occurrence of low shares of unsaturated furan fatty acids (uFuFA). For their detailed analysis, the potential uFuFA were enriched by centrifugal partition chromatography (CPC) or countercurrent chromatography (CCC) followed by silver ion chromatography from a 4,7,10,13,16,19-docosahexaenoic acid ethyl ester oil, a 5,8,11,14,17-eicosapentaenoic acid ethyl ester oil and a latex glove extract. Subsequent gas chromatography with mass spectrometry (GC/MS) analysis enabled the detection of 16 individual uFuFA isomers with a double bond in conjugation with the central furan moiety. In either case, four instead of two uFuFA isomers previously reported in food, respectively, were detected by GC/MS. These isomers showed characteristic elution and abundance patterns in GC/MS chromatograms which indicated the presence of two pairs of cis/trans-isomers (geometrical isomers).

The preventive effect of mussel oil on gestational diabetes mellitus in pregnant mice fed by a high-fat and high-sucrose diet

The present study aimed to investigate the preventive effect of mussel oil (MO) on gestational diabetes mellitus (GDM) in mice fed by a high-fat and high-sucrose (HFHS) diet. Pregnant mice were allocated to four groups: normal diet + corn oil (CO), HFHS + CO, HFHS + fish oil (FO), and HFHS + MO. The total n-3 polyunsaturated fatty acids (PUFAs) in MO (51.30%) and FO (48.25%) were comparable (mainly C22:6n-3 and C20:5n-3). HFHS + MO and HHFS + FO had a significantly lower area under the curve (AUC) for the oral glucose tolerance test (OGTT) than the HFHS + CO group. The HFHS + MO group but not HFHS + FO group had a significantly lower AUC for the insulin tolerance test (ITT) than the HFHS + CO group. The HFHS + MO group had significantly lower homeostasis model assessment-insulin resistance (HOMA-IR) and fasting serum insulin than the HHFS + FO and HFHS + CO groups. Liver sphingosine kinase 1 (SphK1) was significantly higher, while SphK2, Akt, and P-Akt were significantly lower in the HFHS + CO group compared with the normal diet + CO group. The HFHS + MO group but not the HFHS + FO group had significantly higher SphK2, Akt, and P-Akt than the HFHS + CO group. SphK2 had a strong negative correlation with the AUC for the OGTT (r = -0.759, p = 0.001) and insulin tolerance test (ITT) (r = -0.637; p = 0.008), fasting serum insulin (r = -0.594, p = 0.015), fasting blood glucose (r = -0.587, p = 0.017) and HOMA-IR (r = -0.629, p = 0.009) and a strong positive correlation with Akt (r = 0.594, p = 0.015) and P-Akt (r = 0.676, p = 0.004). In conclusion, mussel oil improved glucose intolerance and insulin resistance during mice pregnancy, which was superior to the effects of fish oil.

Oxysterols in catfish skin secretions (Arius bilineatus, Val.) exhibit anti-cancer properties

The edible catfish Arius bilineatus, (Valenciennes) elaborates a proteinaceous gel-like material through its epidermis when threatened or injured. Our on-going studies on this gel have shown it to be a complex mixture of several biologically active molecules. Anti-cancer studies on lipid fractions isolated from the gel-like materials showed them to be active against several cancer cell lines. This prompted us to investigate further the lipid composition of the catfish epidermal gel secretions (EGS). Analysis of the lipid fraction of EGS resulted in identification of 12 oxysterols including cholesterol and 2 deoxygenated steroids i.e., 7α-hydroxy cholesterol, 7β-hydroxycholesterol, 5,6 epoxycholesterol, 3β-hydroxycholest-5-ene-7-one and cholesta-3,5-dien-7-one. Progesterone, cholest-3,5-diene, cholesta-2,4-diene, cholest-3,5,6-triol and 4-cholesten-3-one were found as minor components, and were identified through their MS, ¹HNMR and FTIR spectral data and were compared with those of the standards. Cholest-3,6-dione, cholesta-4,6-diene-3-one, cholesta-2,4-diene, and cholesta-5,20(22)-dien-3-ol were found only in trace amounts and were identified by GC/MS/MS spectral data. Since cholesterol is the major component of EGS, the identified oxysterols (OS) are presumably cholesterol oxidation products. Many of the identified OS are known important biological molecules that play vital physiological role in the producer and recipient organisms. We report herein the effects of these sterols on three human cancer cell lines in vitro, i.e., K-562 (CML cell line), MDA MB-231 (estrogen positive breast cancer cell line) and MCF-7 (estrogen negative breast cancer cell line). Interestingly significant (p < 0.05) dose differences were observed between tested OS on cell types used. The presence of these sterols in EGS may help explain some aspects of the physiological activities of fraction B (FB) prepared from EGS, such as enhanced wound and diabetic ulcer healing, anti-inflammatory action and cytotoxic activities reported in our previous studies. The anti-proliferative actions of some of these oxysterols especially the cholesterol 3,5,6-triol (#5) as established on selected cancer cell lines in this study support our previous studies and make them candidates for research for human application.

Furan Fatty Acids in Some 20 Fungi Species: Unique Profiles and Quantities

Furan fatty acids (FuFAs) are a group of excellent antioxidants in food. Since data in fungi were scarce, 37 commercial or collected edible and meadow fungi were analyzed on FuFA patterns and contents. FuFA amounts in fresh fungi ranged from not detectable (n = 2) to 40 mg/100 g fungi dry weight. Fresh samples of the popular edible fungi genera Agaricus and Pleurotus showed comparable FuFA contents of 9.0-33 mg/100 g fungi dry weight. The unique FuFA profile of the fungi was dominated by 9-(3,4-dimethyl-5-pentylfuran-2-yl)-nonanoic acid (9D5). In addition, the uncommon 9-(3,4-dimethyl-5-butylfuran-2-yl)-nonanoic acid (9D4) was present in 30% of the samples with contents of up to 0.2 mg/100 g fungi dry weight. Countercurrent separation techniques were used to isolate the main FuFA 9D5, to verify the presence of 9D4, and to determine ultra-traces of 11-(3,4-dimethyl-5-pentylfuran-2-yl)-undecanoic acid (11D5), which may have been assimilated by the fungi from the substrate.

Contribution of Lipids to the Flavor of Mussel (Mytilus edulis) Maillard Reaction Products

Lipid oxidation and the Maillard reaction are two of the most important reactions affecting the flavor of foods that have been heat-processed. To investigate the contribution of lipids to the mussel’s flavor, the mussel’s Maillard reaction products (MRPs) were prepared with polar lipids (mainly phospholipids) and nonpolar lipids (mainly glycerides), respectively. The effects of polar and nonpolar lipids on the flavor of the MRPs were investigated by sensory evaluation, electronic tongue, electronic nose, ultra-performance liquid chromatography-mass-spectrometry (UPLC-MS) and gas chromatography-mass-spectrometry (GC-MS). From the sensory evaluation results, the polar lipid MRPs had the highest scores. The tastes of polar lipid MRPs and nonpolar lipid MRPs were mainly umami, saltiness and sourness, and there were significant differences in their sour tastes. The flavor compounds in the MRPs were mainly inorganic sulfides, organic sulfides and nitrogen oxides. The odor of polar lipid MRPs was stronger than that of nonpolar lipid MRPs, and the seafood flavor was more obvious. A total of 37 volatile compounds were detected by GC-MS, mainly aldehydes, alcohols and ketones. The addition of polar lipids helped the MRPs to produce more volatile compounds. A total of 177 non-volatile compounds (including amino acids and their derivatives and oligopeptides, etc.) were detected in the samples using UPLC-MS. The non-volatile compounds contained in the no-lipid MRPs, polar lipid MRPs and nonpolar lipid MRPs were significantly different. This study provides a theoretical basis and technical support for the production of mussel MRPs.

Understanding the Role and Uses of Alternative Therapies for Management of Rheumatoid Arthritis

With growing popularity of complementary and alternative medicine (CAM) among the individuals with chronic pain and muscular problems, a number of patients with rheumatoid arthritis (RA) show their interest in CAM interventions for disease improvement. Various reports published on CAM are based on animal model of RA however there is often lack of high quality clinical investigations for explaining the success stories of CAM therapies in patients with RA. CAMs having potential to be used for therapy in patients with RA have been identified, however lack of awareness and scepticism of their efficacy has made the patients reluctant to choose these drug less therapies. In this review, we have summarized the existing evidences which suggest promising efficacy of different alternative therapies in managing RA and providing both physical and mental well being to RA patients.

Green-lipped (greenshell™) mussel (Perna canaliculus) extract supplementation in treatment of osteoarthritis: a systematic review

OBJECTIVES

Intervention studies using New Zealand green-lipped or greenshell™ mussel (GSM) (Perna canaliculus) extract in osteoarthritis (OA) patients have shown effective pain relief. This systematic review summarises the efficacy of GSM extracts in the treatment of OA.

METHODS

A literature search of the three databases EMBASE, MEDLINE, and Scopus was performed to identify relevant articles published up to March 2020. Inclusion criteria were clinical trials published in English measuring the effect of supplementation of whole or a lipid extract from GSM on pain and mobility outcomes in OA patients.

RESULTS

A total of nine clinical trials were included in systematic review, from which five studies were considered appropriate for inclusion in a forest plot. Pooled results showed that GSM extracts (lipid extract or whole powder) provide moderate and clinically significant treatment effects on a visual analogue scale (VAS) pain score (effect size: - 0.46; 95% CI - 0.82 to - 0.10; p = 0.01). The whole GSM extract improved gastrointestinal symptoms in OA patients taking anti-inflammatory medications. The GSM extract was considered to be generally well tolerated in most of the studies.

CONCLUSION

The overall analysis showed that GSM provided moderate and clinically meaningful treatment effects on OA pain. However, the current evidence is limited by the number and quality of studies, and further larger and high-quality studies are needed to confirm the effectiveness and to identify the optimal GSM format. Nevertheless, it is worth considering using GSM extracts especially for patients seeking alternative pain relief treatments with fewer side effects compared to conventional treatment.

Unified Approach to Furan Natural Products via Phosphine-Palladium Catalysis

Polyalkyl furans are widespread in nature, often performing important biological roles. Despite a plethora of methods for the synthesis of tetrasubstituted furans, the construction of tetraalkyl furans remains non-trivial. The prevalence of alkyl groups in bioactive furan natural products, combined with the desirable bioactivities of tetraalkyl furans, calls for a general synthetic protocol for polyalkyl furans. This paper describes a Michael-Heck approach, using sequential phosphine-palladium catalysis, for the preparation of various polyalkyl furans from readily available precursors. The versatility of this method is illustrated by the total syntheses of nine distinct polyalkylated furan natural products belonging to different classes, namely the furanoterpenes rosefuran, sesquirosefuran, and mikanifuran; the marine natural products plakorsins A, B, and D and plakorsin D methyl ester; and the furan fatty acids 3D5 and hydromumiamicin.

Lipidomic analysis of non-esterified furan fatty acids and fatty acid compositions in dietary shellfish and salmon by UHPLC/LTQ-Orbitrap-MS

Lipids such as furan fatty acids (F-acids) are the valuable minor bioactive components of food such as fatty fish and plants. They are reported to have positive health benefits, including antioxidant and anti-inflammatory activities. Despite their importance, limited studies are focusing on F-acid determination in dietary seafood. This study aimed to identify and profile non-esterified F-acids and free fatty acids in total lipid extract of seafood such as shellfish and salmon. The lipidomic analysis using liquid chromatography-linear trap quadrupole-orbitrap mass spectrometry led to identifying seven types of free F-acids in shellfish (n = 5) and salmon (n = 4). The identified F-acids were confirmed by their high-resolution masses and acquired mass spectra. The relative concentrations of F-acids in shellfish range from 0.01 to 10.93 mg/100 g of the fillet, and in salmon, 0.01 to 14.21 mg/100 g of the fillet. The results revealed the highest abundance of F-acids in Sakhalin surf clam, Japanese scallop, and a fatty salmon trout. Besides, relative levels of saturated, monounsaturated, and polyunsaturated fatty acids (PUFAs) in these seafoods were compared with each other, suggesting basket clams and salmon trout to have significantly higher levels of PUFAs. The dietary seafoods enriched with F-acids and PUFAs may have possible health benefits. Hence, the applied technique could be a promising tool for rapid detection and analysis of non-esterified fatty acids in food.

Microalgae n-3 PUFAs Production and Use in Food and Feed Industries

N-3 polyunsaturated fatty acids (n-3 PUFAs), and especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are essential compounds for human health. They have been proven to act positively on a panel of diseases and have interesting anti-oxidative, anti-inflammatory or anti-cancer properties. For these reasons, they are receiving more and more attention in recent years, especially future food or feed development. EPA and DHA come mainly from marine sources like fish or seaweed. Unfortunately, due to global warming, these compounds are becoming scarce for humans because of overfishing and stock reduction. Although increasing in recent years, aquaculture appears insufficient to meet the increasing requirements of these healthy molecules for humans. One alternative resides in the cultivation of microalgae, the initial producers of EPA and DHA. They are also rich in biochemicals with interesting properties. After defining macro and microalgae, this review synthesizes the current knowledge on n-3 PUFAs regarding health benefits and the challenges surrounding their supply within the environmental context. Microalgae n-3 PUFA production is examined and its synthesis pathways are discussed. Finally, the use of EPA and DHA in food and feed is investigated. This work aims to define better the issues surrounding n-3 PUFA production and supply and the potential of microalgae as a sustainable source of compounds to enhance the food and feed of the future.

Are Nutraceuticals Beneficial in Chronic Kidney Disease?

Chronic kidney disease (CKD) is a worldwide health problem in which prevalence is constantly rising. The pathophysiology of CKD is complicated and has not been fully resolved. However, elevated oxidative stress is considered to play a vital role in the development of this disease. CKD is also thought to be an inflammatory disorder in which uremic toxins participate in the development of the inflammatory milieu. A healthy, balanced diet supports the maintenance of a good health status as it helps to reduce the risk of the development of chronic diseases, including chronic kidney disease, diabetes mellitus, and hypertension. Numerous studies have demonstrated that functional molecules and nutrients, including fatty acids and fiber as well as nutraceuticals such as curcumin, steviol glycosides, and resveratrol not only exert beneficial effects on pro-inflammatory and anti-inflammatory pathways but also on gut mucosa. Nutraceuticals have attracted great interest recently due to their potential favorable physiological effects on the human body and their safety. This review presents some nutraceuticals in which consumption could exert a beneficial impact on the development and progression of renal disease as well cardiovascular disease.

Effectiveness of a combined New Zealand green-lipped mussel and Antarctic krill oil supplement on markers of exercise-induced muscle damage and inflammation in untrained men

Green-lipped mussel oil (PCSO-524^®) has been shown to attenuate signs and symptoms of exercise-induced muscle damage (EIMD), and krill oil has been shown to have a protective effect against cytokine-induced tissue degradation. The purpose of this study was to compare the effects of PCSO-524^® and ESPO-572^® (75% PCSO-524^® and 25% krill oil) on signs and symptoms of EIMD. Fifty-one untrained men consumed 600 mg/d of PCSO-524^® (n = 24) or ESPO-572^® (n = 27) for 26 d prior to and 72 h following a downhill running bout. Delayed onset muscle soreness (DOMS), pressure pain threshold, limb swelling, range of motion (ROM), isometric torque, and blood markers of inflammation and muscle damage were assessed at baseline, 24, 48 and 72 h post-eccentric exercise. ESPO-572^® was 'at least as good as' PCSO-524^® and both blends were superior (p < 0.05) to placebo in lessening the increase in DOMS at 24, 48, 72 h. ESPO-572^® and PCSO-524^® were protective against joint ROM loss compared to placebo (p < 0.05) at 48 and 72 h. Notably, at 24 and 48 h, joint ROM was higher in the ESPO-572^® compared to the PCSO-524^® group (p < 0.05). No differences between the two blends for the other markers were found. ESPO-572^® is 'at least as good' as PCSO-524^® in reducing markers of muscle damage and soreness following eccentric exercise and was superior to PCSO-524^® in protecting against the loss in joint ROM during recovery. Our data support the use of ESPO-572^®, a combination of green-lipped mussel and krill oil, in mitigating the deleterious effects of EIMD.

High-value compounds from the molluscs of marine and estuarine ecosystems as prospective functional food ingredients: An overview

Extensive biodiversity and availability of marine and estuarine molluscs, along with their their wide-range of utilities as food and nutraceutical resources developed keen attention of the food technologists and dieticians, particularly during the recent years. The current review comprehensively summarized the nutritional qualities, functional food attributes, and bioactive properties of these organisms. Among the phylum mollusca, Cephalopoda, Bivalvia, and Gastropoda were mostly reported for their nutraceutical applications and bioactive properties. The online search tools, like Scifinder/Science Direct/PubMed/Google Scholar/MarinLit database and marine natural product reports (1984-2019) were used to comprehend the information about the molluscs. More than 1334 secondary metabolites were reported from marine molluscs between the periods from 1984 to 2019. Among various classes of specialized metabolites, terpenes were occupied by 55% in gastropods, whereas sterols occupied 41% in bivalves. The marketed nutraceuticals, such as CadalminTM green mussel extract (Perna viridis) and Lyprinol® (Perna canaliculus) were endowed with potential anti-inflammatory activities, and were used against arthritis. Molluscan-derived therapeutics, for example, ziconotide was used as an analgesic, and elisidepsin was used in the treatment of cancer. Greater numbers of granted patents (30%) during 2016-2019 recognized the increasing importance of bioactive compounds from molluscs. Consumption of molluscs as daily diets could be helpful in the enhancement of immunity, and reduce the risk of several ailments. The present review comprehended the high value compounds and functional food ingredients from marine and estuarine molluscs.

Furan fatty acids in enriched ω-3 fish oil: Oxidation kinetics with and without added monomethyl furan fatty acid as potential natural antioxidant

This study investigated the lipid oxidation reactions of furan fatty acids, long-chain ω-3 polyunsaturated fatty acids, and tocopherols in an enriched ω-3 fish oil to better understand their degradation kinetics. Furthermore, the influence of an added monomethyl furan fatty acid 9-(3-methyl-5-pentylfuran-2-yl) nonanoic acid (9M5) at 50-250 µM on the oxidation reactions was evaluated. The results showed that the fish oil was rich in monomethyl and dimethyl furan fatty acids (c = 1.3 g/100 g lipids). Upon oxidation of the fish oil, the dimethyl furan fatty acids degraded faster than the monomethyl ones, but also faster than tocopherols. The addition of 9M5 revealed antioxidant activity: It inhibited the degradation of the ω-3 polyunsaturated fatty acids and the formation of primary and secondary lipid oxidation products, and slowed down the degradation of the furan fatty acids and tocopherols. This research offers new insights into the importance of furan fatty acids in lipid oxidation reactions.

Recent Updates on Anti-Inflammatory and Antimicrobial Effects of Furan Natural Derivatives

The furan nucleus is found in a large number of biologically active materials. In recent years, many natural furan derivatives were isolated and their biological effects were investigated. In this review, we focused on the anti-inflammatory and antimicrobial effects of some natural furans and discussed their effects on the immune system. Our investigation revealed that furan natural derivatives have effective antioxidant activities and exert regulatory effects on various cellular activities by modifying some signaling pathways such as MAPK (mitogen-activated Protein Kinase) and PPAR-ɣ (peroxisome proliferator-activated receptor gamma). The antimicrobial activity of these natural compounds was performed through selective inhibition of microbial growth and modification of enzymes. Further studies are needed for isolation and detection of different furan derivatives from natural compounds and investigation of their precise mechanisms for revealing health beneficial effects of these compounds.

Valuable furan fatty acids in soybeans and soy products

Furan fatty acids (FuFAs) are valuable minor compounds in our food with excellent antioxidant properties. Naturally occurring FuFAs are characterised by a central furan moiety with one or two methyl groups in β-/β’-position of the heterocycle (monomethyl- or M-FuFAs and dimethyl- or D-FuFAs). Comparably high concentrations of D-/M-FuFAs were reported in soybeans, but soy is often consumed as a processed product, such as full-fat soy flour and flakes, soy drink, tofu and texturised soy protein (TSP). Due to the chemical lability of D-/M-FuFAs, e.g. in the presence of light or oxygen, a degradation during the processing is possible. For this purpose, freshly harvested soybeans (n = 4) and differently processed soybean products (n = 22) were analysed on FuFAs. Three FuFAs, i.e. 11-(3,4-dimethyl-5-pentylfuran-2-yl)-undecanoic acid (11D5), 9-(3,4-dimethyl-5-pentylfuran-2-yl)-nonanoic acid (9D5), and 9-(3-methyl-5-pentylfuran-2-yl)-nonanoic acid (9M5), were identified and quantified in all fresh soybeans and most of the processed soy products (n = 20). A trend towards lower D-/M-FuFA contents in higher processed products was observable. Lower FuFA concentrations were usually accompanied with a decrease of the share of the less stable D-FuFAs (9D5, 11D5) in favour of the M-FuFA 9M5. Furthermore, one or two 3,4-nonmethylated furan fatty acids (N-FuFAs), i.e. 8-(5-hexylfuran-2-yl)-octanoic acid (8F6) and partly 7-(5-heptylfuran-2-yl)-heptanoic acid (7F7), were detected in all processed products, but not in the freshly harvested soybeans. Our results indicate that D-/M-/N-FuFAs may serve as suitable markers for both, careful manufacturing processes and adequate storage conditions of soy products.

Nutrition, Health, and Disease: Role of Selected Marine and Vegetal Nutraceuticals

The investigation of new alternatives for disease prevention through the application of findings from dietary and food biotechnology is an ongoing challenge for the scientific community. New nutritional trends and the need to meet social and health demands have inspired the concept of functional foods and nutraceuticals which, in addition to their overall nutritional value, present certain properties for the maintenance of health. However, these effects are not universal. Nutrigenetics describes how the genetic profile has an impact on the response of the body to bioactive food components by influencing their absorption, metabolism, and site of action. The EbioSea Program, for biomarine prospection, and the Blue Butterfly Program, for the screening of vegetable-derived bioproducts, have identified a new series of nutraceuticals, devoid of side effects at conventional doses, with genotype-dependent preventive and therapeutic activity. Nutrigenomics and nutrigenetics provide the opportunity to explore the inter-individual differences in the metabolism of and response to nutrients, achieving optimal results. This fact leads to the concept of personalized nutrition as opposed to public health nutrition. Consequently, the development and prescription of nutraceuticals according to the individual genetic profile is essential to improve their effectiveness in the prevention and natural treatment of prevalent diseases.

Association of Untargeted Urinary Metabolomics and Lung Cancer Risk Among Never-Smoking Women in China

IMPORTANCE

Chinese women have the highest rate of lung cancer among female never-smokers in the world, and the etiology is poorly understood.

OBJECTIVE

To assess the association between metabolomics and lung cancer risk among never-smoking women.

DESIGN, SETTING, AND PARTICIPANTS

This nested case-control study included 275 never-smoking female patients with lung cancer and 289 never-smoking cancer-free control participants from the prospective Shanghai Women's Health Study recruited from December 28, 1996, to May 23, 2000. Validated food frequency questionnaires were used for the collection of dietary information. Metabolomic analysis was conducted from November 13, 2015, to January 6, 2016. Data analysis was conducted from January 6, 2016, to November 29, 2018.

EXPOSURES

Untargeted ultra-high-performance liquid chromatography-tandem mass spectrometry and nuclear magnetic resonance metabolomic profiles were characterized using prediagnosis urine samples. A total of 39 416 metabolites were measured.

MAIN OUTCOMES AND MEASURES

Incident lung cancer.

RESULTS

Among the 564 women, those who developed lung cancer (275 participants; median [interquartile range] age, 61.0 [52-65] years) and those who did not develop lung cancer (289 participants; median [interquartile range] age, 62.0 [53-66] years) at follow-up (median [interquartile range] follow-up, 10.9 [9.0-11.7] years) were similar in terms of their secondhand smoke exposure, history of respiratory diseases, and body mass index. A peak metabolite, identified as 5-methyl-2-furoic acid, was significantly associated with lower lung cancer risk (odds ratio, 0.57 [95% CI, 0.46-0.72]; P < .001; false discovery rate = 0.039). Furthermore, this peak was weakly correlated with self-reported dietary soy intake (ρ = 0.21; P < .001). Increasing tertiles of this metabolite were associated with lower lung cancer risk (in comparison with first tertile, odds ratio for second tertile, 0.52 [95% CI, 0.34-0.80]; and odds ratio for third tertile, 0.46 [95% CI, 0.30-0.70]), and the association was consistent across different histological subtypes and follow-up times. Additionally, metabolic pathway analysis found several systemic biological alterations that were associated with lung cancer risk, including 1-carbon metabolism, nucleotide metabolism, oxidative stress, and inflammation.

CONCLUSIONS AND RELEVANCE

This prospective study of the untargeted urinary metabolome and lung cancer among never-smoking women in China provides support for the hypothesis that soy-based metabolites are associated with lower lung cancer risk in never-smoking women and suggests that biological processes linked to air pollution may be associated with higher lung cancer risk in this population.

The Preventive Effects of Greenshell Mussel (Perna canaliculus) on Early-Stage Metabolic Osteoarthritis in Rats with Diet-Induced Obesity

The prevalence of osteoarthritis (OA) is rising worldwide, with the most pronounced increase being in the category of metabolic-associated osteoarthritis (MetOA). This is predicted to worsen with the global rise in aging societies and obesity. To address this health burden, research is being conducted to identify foods that can reduce the incidence or severity of MetOA. Oil from the Greenshell mussel (Perna canaliculus) (GSM), a native New Zealand shellfish, has been successfully used to reduce OA symptoms. The current study assessed the effect of including flash-dried powder from whole GSM meat as part of a normal (control) versus high-fat/high-sugar (HFHS) diet for 13 weeks on the development of MetOA in rats. Rats fed a HFHS diet developed metabolic dysregulation and obesity with elevated plasma leptin and HbA1C concentrations. Visible damage to knee joint cartilage was minimal, but plasma levels of C telopeptide of type II collagen (CTX-II), a biomarker of cartilage degradation, were markedly higher in HFHS-fed rats compared to control-fed rats. However, rats fed the HFHS diet containing GSM had significantly reduced serum CTX-II. Inclusion of GSM in rats fed the control diet also lowered CTX-II. These findings suggest that dietary GSM can reduce the incidence or slow the progression of early MetOA.

Furanoic Lipid F-6, A Novel Anti-Cancer Compound that Kills Cancer Cells by Suppressing Proliferation and Inducing Apoptosis

Identifying novel anti-cancer drugs is important for devising better cancer treatment options. In a series of studies designed to identify novel therapeutic compounds, we recently showed that a C-20 fatty acid (12,15-epoxy-13,14-dimethyleicosa-12,14-dienoic acid, a furanoic acid or F-6) present in the lipid fraction of the secretions of the Arabian Gulf catfish skin (Arius bilineatus Val.; AGCS) robustly induces neutrophil extracellular trap formation. Here, we demonstrate that a lipid mix (Ft-3) extracted from AGCS and F-6, a component of Ft-3, dose dependently kill two cancer cell lines (leukemic K-562 and breast MDA MB-231). Pure F-6 is approximately 3.5 to 16 times more effective than Ft-3 in killing these cancer cells, respectively. Multiplex assays and network analyses show that F-6 promotes the activation of MAPKs such as Erk, JNK, and p38, and specifically suppresses JNK-mediated c-Jun activation necessary for AP-1-mediated cell survival pathways. In both cell lines, F-6 suppresses PI3K-Akt-mTOR pathway specific proteins, indicating that cell proliferation and Akt-mediated protection of mitochondrial stability are compromised by this treatment. Western blot analyses of cleaved caspase 3 (cCasp3) and poly ADP ribose polymerase (PARP) confirmed that F-6 dose-dependently induced apoptosis in both of these cell lines. In 14-day cell recovery experiments, cells treated with increasing doses of F-6 and Ft-3 fail to recover after subsequent drug washout. In summary, this study demonstrates that C-20 furanoic acid F-6, suppresses cancer cell proliferation and promotes apoptotic cell death in leukemic and breast cancer cells, and prevents cell recovery. Therefore, F-6 is a potential anti-cancer drug candidate.

Total Synthesis of the Tetrasubstituted Furan Fatty Acid Metabolite CeDFP via Au-Catalyzed Intermolecular Alkyne Hydroarylation

The first total synthesis of the tetrasubstituted furan fatty acid (FFA) metabolite 5-[(1 E)-2-carboxyethenyl]-3,4-dimethyl-2-furanpentanoic acid (CeDFP) is reported. CeDFP is a FFA metabolite isolated from shark livers and is related to the known FFA metabolites CMPF and CMPentylF. Key elements of the synthetic route to CeDFP include an iodine-promoted 5- endo- dig cyclization of a 1,2-alkyne diol, a methyllithium-mediated insertion of the C₃-methyl group, and a Au(I)-catalyzed intermolecular hydroarylation to introduce the unsaturated ester.

Furanoid F-Acid F6 Uniquely Induces NETosis Compared to C16 and C18 Fatty Acids in Human Neutrophils

Various biomolecules induce neutrophil extracellular trap (NET) formation or NETosis. However, the effect of fatty acids on NETosis has not been clearly established. In this study, we focused on the NETosis-inducing ability of several lipid molecules. We extracted the lipid molecules present in Arabian Gulf catfish (Arius bilineatus, Val) skin gel, which has multiple therapeutic activities. Gas chromatography⁻mass spectrometry (GC-MS) analysis of the lipid fraction-3 from the gel with NETosis-inducing activity contained fatty acids including a furanoid F-acid (F6; 12,15-epoxy-13,14-dimethyleicosa-12,14-dienoic acid) and common long-chain fatty acids such as palmitic acid (PA; C16:0), palmitoleic acid (PO; C16:1), stearic acid (SA; C18:0), and oleic acid (OA; C18:1). Using pure molecules, we show that all of these fatty acids induce NETosis to different degrees in a dose-dependent fashion. Notably, F6 induces a unique form of NETosis that is rapid and induces reactive oxygen species (ROS) production by both NADPH oxidase (NOX) and mitochondria. F6 also induces citrullination of histone. By contrast, the common fatty acids (PA, PO, SA, and OA) only induce NOX-dependent NETosis. The activation of the kinases such as ERK (extracellular signal-regulated kinase) and JNK (c-Jun N-terminal kinase) is important for long-chain fatty acid-induced NETosis, whereas, in F-acid-induced NETosis, Akt is additionally needed. Nevertheless, NETosis induced by all of these compounds requires the final chromatin decondensation step of transcriptional firing. These findings are useful for understanding F-acid- and other fatty acid-induced NETosis and to establish the active ingredients with therapeutic potential for regulating diseases involving NET formation.

Uncommon Fatty Acids and Cardiometabolic Health

Cardiovascular disease (CVD) is a major cause of mortality. The effects of several unsaturated fatty acids on cardiometabolic health, such as eicosapentaenoic acid (EPA) docosahexaenoic acid (DHA), α linolenic acid (ALA), linoleic acid (LA), and oleic acid (OA) have received much attention in past years. In addition, results from recent studies revealed that several other uncommon fatty acids (fatty acids present at a low content or else not contained in usual foods), such as furan fatty acids, n-3 docosapentaenoic acid (DPA), and conjugated fatty acids, also have favorable effects on cardiometabolic health. In the present report, we searched the literature in PubMed, Embase, and the Cochrane Library to review the research progress on anti-CVD effect of these uncommon fatty acids. DPA has a favorable effect on cardiometabolic health in a different way to other long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFAs), such as EPA and DHA. Furan fatty acids and conjugated linolenic acid (CLNA) may be potential bioactive fatty acids beneficial for cardiometabolic health, but evidence from intervention studies in humans is still limited, and well-designed clinical trials are required. The favorable effects of conjugated linoleic acid (CLA) on cardiometabolic health observed in animal or in vitro cannot be replicated in humans. However, most intervention studies in humans concerning CLA have only evaluated its effect on cardiometabolic risk factors but not its direct effect on risk of CVD, and randomized controlled trials (RCTs) will be required to clarify this point. However, several difficulties and limitations exist for conducting RCTs to evaluate the effect of these fatty acids on cardiometabolic health, especially the high costs for purifying the fatty acids from natural sources. This review provides a basis for better nutritional prevention and therapy of CVD.

Protective Effects of a Lipid Extract from Hard-Shelled Mussel (Mytilus coruscus) on Intestinal Integrity after Lipopolysaccharide Challenge in Mice

This study investigated the protective effects of a lipid extract from hard-shelled mussel (HMLE) on intestinal integrity and the underlying mechanisms after a lipopolysaccharide (LPS) challenge in mice by using a 3 × 2 factorial design. Mice received olive oil, fish oil, and HMLE (n = 12 per group) by using gastric gavage for six weeks, respectively. Then half the mice in each group was injected intraperitoneally with LPS and the other half with phosphate buffered saline. Four hours after injection, mice were sacrificed and samples were collected. n-3 PUFAs were significantly enriched in erythrocytes following fish oil and HMLE supplementation. Both fish oil and HMLE improved intestinal morphology by restoring the ileac villus height and barrier function, which is indicated by decreased colonic myeloperoxidase activity and increased diamine oxidase activity as well as enhanced mRNA expression of intestinal tight junction proteins known as occludin and claudin-1 when compared with olive oil. In addition, both fish oil and HMLE increased colon production and the expression of anti-inflammatory cytokine, IL-10, while they inhibited the abnormal production and expression of pro-inflammatory cytokines including TNF-α, IL-1β, and IL-6 relative to the olive oil. Lastly, in comparison with olive oil, both fish oil and HMLE downregulated the TLR-4 signaling pathway by reducing the expression of two key molecules in this pathway, which are called TLR-4 and MyD88. These results suggest that HMLE had a protective effect on intestinal integrity after the LPS challenge, which was equivalent to that of fish oil. This effect might be associated with the regulation of inflammatory mediators and the inhibition of the TLR-4 signaling pathway.

The Effects of PCSO-524®, a Patented Marine Oil Lipid derived from the New Zealand Green Lipped Mussel (Perna canaliculus), on Pulmonary and Respiratory Muscle Function in Non-asthmatic Elite Runners

Habitual endurance training may be associated with mild airway inflammation and subsequent deterioration in lung function. PCSO-524™ (Lyprinol®/Omega-XL®), a supplement extracted from the New Zealand green-lipped mussel (Perna canaliculus), has been shown to moderate airway inflammation in asthmatic subjects. The purpose of this study was to determine whether supplementation with PCSO-524™ improves pulmonary and respiratory muscle function in non-asthmatic elite runners. Sixteen male, non-asthmatic elite runners were randomly assigned to either a treatment (PCSO-524™; 1 capsule contains 50 mg n-3 polyunsaturated fatty acids and 100 mg olive oil, n=8) or placebo (1 capsule contains 150 mg olive oil; n=8) group. During the supplementation period, subjects ingested 8 capsules of either treatment or placebo per day for 12 weeks. Resting pulmonary and respiratory muscle function testing were assessed at baseline and every two weeks throughout the 12 week supplementation period. No significant between-or within-subjects main effects were observed in forced vital capacity, forced expiratory volume in 1-second, forced expiratory flow from 25-75% of lung volume (FEF25-75), peak expiratory flow, maximal voluntary ventilation, maximal inspiratory mouth pressure, and closing volume (p>0.05). A significant within-subjects main effect was observed in maximal expiratory mouth pressure (PEmax) (p=0.024) and lung diffusion capacity (DLCO) (p<0.0001), but no significant between-subjects main effects were observed for PEmax and DLCO (p>0.05). A significant treatment by time interaction was observed in FEF25-75 (p=0.026) and DLCO (p=0.024), but no other significant interactions were observed (all p>0.05). Supplementation with PCSO-524™ (Lyprinol®/Omega-XL®) does not improve pulmonary or respiratory muscle function in non-asthmatic elite runners.

Greenshell™ Mussels: A Review of Veterinary Trials and Future Research Directions

The therapeutic benefits of Greenshell™ mussel (GSM; Perna canaliculus) preparations have been studied using in vitro test systems, animal models, and human clinical trials focusing mainly on anti-inflammatory and anti-arthritic effects. Activity is thought to be linked to key active ingredients that include omega-3 polyunsaturated fatty acids, a variety of carotenoids and other bioactive compounds. In this paper, we review the studies that have been undertaken in dogs, cats, and horses, and outline new research directions in shellfish breeding and high-value nutrition research programmes targeted at enhancing the efficacy of mussel and algal extracts. The addition of GSM to animal diets has alleviated feline degenerative joint disease and arthritis symptoms, and chronic orthopaedic pain in dogs. In horses, GSM extracts decreased the severity of lameness and joint pain and provided improved joint flexion in limbs with lameness attributed to osteoarthritis. Future research in this area should focus on elucidating the key active ingredients in order to link concentrations of these active ingredients with their pharmacokinetics and therapeutic effects. This would enable consistent and improved efficacy from GSM-based products for the purpose of improved animal health.

Fish oil feeding attenuates neuroinflammatory gene expression without concomitant changes in brain eicosanoids and docosanoids in a mouse model of Alzheimer's disease

BACKGROUND

Neuroinflammation is a recognized hallmark of Alzheimer's disease, along with accumulation of amyloid-β plaques, neurofibrillary tangles and synaptic loss. n-3 polyunsaturated fatty acids (PUFA) and molecules derived from them, including eicosapentaenoic acid-derived eicosanoids and docosahexaenoic acid-derived docosanoids, are known to have both anti-inflammatory and pro-resolving properties, while human observational data links consumption of these fatty acids to a decreased risk of Alzheimer's disease. Few studies have examined the neuroinflammation-modulating effects of n-3 PUFA feeding in an Alzheimer's disease-related model, and none have investigated whether these effects are mediated by changes in brain eicosanoids and docosanoids. Here, we use both a fat-1 transgenic mouse and a fish oil feeding model to study the impact of increasing tissue n-3 PUFA on neuroinflammation and the production of pro-inflammatory and pro-resolving lipid mediators.

METHODS

Fat-1 mice, transgenic animals that can convert n-6 to n-3 PUFA, and their wildtype littermates were fed diets containing either fish oil (high n-3 PUFA) or safflower oil (negligible n-3 PUFA) from weaning to 12 weeks. Animals then underwent intracerebroventricular infusion of either amyloid-β 1-40 or a control peptide. Hippocampi were collected from non-surgery and surgery animals 10 days after infusion. Microarray was used to measure enrichment of inflammation-associated gene categories and expression of genes involved in the synthesis of lipid mediators. Results were validated by real-time PCR in a separate cohort of animals. Lipid mediators were measured via liquid chromatography tandem mass spectrometry.

RESULTS

Fat-1 and wildtype mice fed fish oil had higher total hippocampal DHA than wildtype mice fed the safflower oil diet. The safflower-fed mice, but not the fat-1 or fish oil-fed mice, had significantly increased expression in gene ontology categories associated with inflammation in response to amyloid-β infusion. These effects were independent of changes in the expression of genes involved in the synthesis of eicosanoids or docosanoids in any group. Gene expression was replicated upon validation in the wildtype safflower and fish oil-fed, but not the fat-1 mice. Protectin, maresin and D and E series resolvins were not detected in any sample. There were no major differences in levels of other eicosanoids or docosanoids between any of the groups in response to amyloid-β infusion.

CONCLUSIONS

Fish oil feeding decreases neuroinflammatory gene expression in response to amyloid-β. Neither amyloid-β infusion or increasing brain DHA affects the brain concentrations of specialized pro-resolving mediators in this model, or the concentrations of most other eicosanoids and docosanoids.

Review of anti-inflammatory, immune-modulatory and wound healing properties of molluscs

ETHNOPHARMACOLOGICAL RELEVANCE

This review focuses on traditional and contemporary anti-inflammatory uses of mollusc-derived products summarising all the in vitro, in vivo and human clinical trials that have tested the anti-inflammatory activity of molluscan natural products. Inflammatory conditions, burns and wounds have been an ongoing concern for human health since the early era of civilisation. Many texts from ancient medicine have recorded the symptoms, signs and treatments for these conditions. Natural treatments are well-documented in traditional European medicine, Traditional Chinese Medicine (TCM), Siddha and ancient Mediterranean and African traditional medicine and include a surprisingly large number of molluscan species.

MATERIALS AND METHODS

An extensive review of the Materia Medica and scientific literature was undertaken using key word searches for "mollusc" and "anti-inflammatory" or "immunomodulatory" or "wound healing".

RESULTS

Molluscs have been used in ethnomedicine by many traditional cultures to treat different aspects of inflammatory conditions. We found 104 different anti-inflammatory preparations from a variety of molluscan species, of which 70 were from the well-documented Traditional Chinese Medicine (TCM). This traditional use of molluscs has driven the testing for inflammatory activity in extracts from some species in the phylum Mollusca, with 20 in vitro studies, 40 in vivo animal studies and 14 human clinical trials performed to substantiate the anti-inflammatory and wound healing activity of molluscs. Some of these studies have led to the approval of mollusc-derived products to be used as over-the-counter (OTC) nutraceuticals, like Lyprinol® and Biolane™ from the New Zealand green lipped mussel Perna canaliculus.

CONCLUSION

Natural products provide important leads for the development of pharmaceuticals, including anti-inflammatory agents. Only a small proportion of the molluscan traditional medicines have been tested to confirm their anti-inflammatory activity and most screening studies have tested crude extracts from molluscs without any chemical characterisation. This highlights the need for further research to strategically identify the anti-inflammatory compounds in molluscan medicines to provide leads for novel anti-inflammatory drugs in the future.