Polyunsaturated Fatty Acid Profiles Research Articles

Current Insights into the Effects of Dietary α-Linolenic Acid Focusing on Alterations of Polyunsaturated Fatty Acid Profiles in Metabolic Syndrome.

The plant-derived α-linolenic acid (ALA) is an essential n-3 acid highly susceptible to oxidation, present in oils of flaxseeds, walnuts, canola, perilla, soy, and chia. After ingestion, it can be incorporated in to body lipid pools (particularly triglycerides and phospholipid membranes), and then endogenously metabolized through desaturation, elongation, and peroxisome oxidation to eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), with a very limited efficiency (particularly for DHA), beta-oxidized as an energy source, or directly metabolized to C18-oxilipins. At this moment, data in the literature about the effects of ALA supplementation on metabolic syndrome (MetS) in humans are inconsistent, indicating no effects or some positive effects on all MetS components (abdominal obesity, dyslipidemia, impaired insulin sensitivity and glucoregulation, blood pressure, and liver steatosis). The major effects of ALA on MetS seem to be through its conversion to more potent EPA and DHA, the impact on the n-3/n-6 ratio, and the consecutive effects on the formation of oxylipins and endocannabinoids, inflammation, insulin sensitivity, and insulin secretion, as well as adipocyte and hepatocytes function. It is important to distinguish the direct effects of ALA from the effects of EPA and DHA metabolites. This review summarizes the most recent findings on this topic and discusses the possible mechanisms.

Melosira nummuloides Ethanol Extract Ameliorates Alcohol-Induced Liver Injury by Affecting Metabolic Pathways.

Melosira nummuloides is a microalga with a nutritionally favorable polyunsaturated fatty acid profile. In the present study, M. nummuloides ethanol extract (MNE) was administered to chronic-binge alcohol-fed mice and alcohol-treated HepG2 cells, and its hepatoprotective effects and underlying mechanisms were investigated. MNE administration reduced triglyceride (TG), total cholesterol (T-CHO), and liver injury markers, including aspartate transaminase (AST) and alanine transaminase (ALT), in the serum of chronic-binge alcohol-fed mice. However, MNE administration increased the levels of phosphorylated adenosine monophosphate-activated protein kinase (P-AMPK/AMPK) and PPARα, which was accompanied by a decrease in SREBP-1; this indicates that MNE can inhibit adipogenesis and improve fatty acid oxidation. Moreover, MNE administration upregulated the expression of antioxidant enzymes, including SOD, NAD(P)H quinone dehydrogenase 1, and GPX, and ameliorated alcohol-induced inflammation by repressing the Akt/NFκB/COX-2 pathway. Metabolomic analysis revealed that MNE treatment modulated many lipid metabolites in alcohol-treated HepG2 cells. Our study findings provide evidence for the efficacy and mechanisms of MNE in ameliorating alcohol-induced liver injury.

Saturated, monounsaturated and polyunsaturated fatty acid profiles of commercially important traditional and new improved red and white rice varieties of Sri Lanka

The present study evaluated saturated, monounsaturated, and polyunsaturated fatty acid (FA) profiles of seven new improved and three traditional red and white rice varieties (RV) of Sri Lanka. Oil was extracted from whole grain rice flour, derivatized to methyl esters, and analyzed by gas chromatography (n = 3 each). Results showed significant differences (p < 0.05) in FA profiles among the RV, red vs white RV, and traditional vs new improved RV. The oil % of RV varied from 1.94–3.19%. Total FAs, saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs), polyunsaturated fatty acids (PUFAs), total unsaturated FAs, and PUFAs to SFAs ratios of studied RV varied from 19.40–31.90, 4.40–7.04, 8.35–13.60, 6.65–11.26 and 15.00–24.86 mg/g of rice and 1.44–1.83 respectively. The tested RV had four omega-6 FAs while omega-3 FAs were absent. The major FAs found in all RV were palmitic, oleic, and linoleic acids and these three FAs together contributed to 88–95% of the total FAs present in rice. Among these FAs, 70–76% were unsaturated FAs. Considering all, RV consisting of healthy fatty acid profiles could be identified by studying their total fatty acid profile rather than studying their oil % and the total fatty acid contents.

Weight loss induced by a hypocaloric diet with or without fish oil supplementation re-established iron and omega-3 fatty acid homeostasis in middle-aged women with obesity: A post-hoc analysis of a randomized controlled trial

ObjectiveMiddle-aged women with obesity are at increased risk of iron overload and iron disorder is known to disrupt n-3 polyunsaturated fatty acid homeostasis. We evaluated relationships between pretreatment hemoglobin and n-3 polyunsaturated fatty acid levels, and tested whether pretreatment hemoglobin contributed to inter-individual variability in weight loss with special focus on changes in body weight, iron and n-3 polyunsaturated fatty acid profiles. Study design117 middle and older aged women with obesity and more than two metabolic abnormalities were randomized to a 12-week hypocaloric diet without or with fish oil supplementation. Blood iron biomarker and erythrocyte membrane phospholipid profiles were evaluated. Main outcomeThe absolute change from baseline to week 12 in serum iron and erythrocyte n-3 polyunsaturated fatty acid levels according to pretreatment hemoglobin tertiles and fish oil supplementation. ResultsA Pearson correlation analysis showed that pretreatment hemoglobin levels were negatively correlated with linoleic acid (r = −0.231), α-linoleic acid (r = −0.279), and n-3 polyunsaturated fatty acid (r = −0.217) (all p < 0.05). Dietary weight loss markedly enhanced erythrocyte membrane lipids of linoleic acid, α-linoleic acid, and n-6 and n-3 polyunsaturated fatty acid only in those women with the highest pretreatment hemoglobin levels (tertile 3) (all p < 0.05). Fish oil supplementation increased bioavailable iron in women with moderate pretreatment hemoglobin levels (tertile 2) (p < 0.05) and, to a lesser extent, prevented a reduction in circulating iron in those with the lowest hemoglobin levels (tertile 1). ConclusionDietary weight loss is an effective treatment program to manage obesity-related iron and n-3 polyunsaturated fatty acid disorders, particularly for middle-aged women with obesity and iron overload.

Dietary enrichment with fish oil improved n–3 LC-PUFA profile in aquacultured Sardinella brasiliensis fillet

The effects of dietary supplementation with different fish oil inclusions on proximate composition and fatty acid profile in Sardinella brasiliensis fillets were investigated. For this, 375 S. brasiliensis (32.52 ± 5.93 g) were divided into 15 experimental units, comprising a control group with no fish oil supplementation (0%), and four treated groups with fish oil supplementation at concentrations of 0.3%, 0.6%, 0.9% and 1.2%. On the 45th day, linoleic acid was significantly higher (10.76 ± 0.30) in the 0% treatment, while eicosapentaenoic acid was significantly higher on the 30th (0.80 ± 0.14 and 0.90 ± 0.02) and 45th days (0.56 ± 0.13 and 0.66 ± 0.02) in treatments 0.9% and 1.2%, respectively. Docosahexaenoic acid was significantly higher in the 0.9% and 1.2% treatments on the 30th day compared to the 0.3% and 0% groups. Docosapentaenoic acid was significantly different between the groups on the 30th and 45th days. The moisture was reduced (61.30 ± 0.68 and 60.32 ± 0.72) in the 0.3% and 0.6% treatments, respectively. Fillet lipid increased in the 0.6% and 0.9% treatments. However, 0.9% and 1.2% treatments equally improved the polyunsaturated fatty acid profile in sardine fillet on the 30th day of treatment.

Seasonal and culture period variations in the lipid and fatty acid content of Ulva lactuca cultivated in Mikhmoret onshore (Israel)

Abstract The use of high-value fatty acids (FA), omega-3 (n-3), and omega-6 (n-6) from seaweed could relieve the pressure from natural wild fish sources and reduce overfishing worldwide. This research is designed to explore how the harvest season (winter, spring, and summer) and culture period influence the biomass production yield, lipid content, and FA composition in the green seaweed Ulva sp. The studied seaweed was grown in plastic sleeves with flowthrough seawater in Mikhmoret (East Mediterranean, Israel) from July 2019 to December 2020. The Ulva species was identified as Ulva lactuca Linnaeus by DNA barcoding using rbcL, ITS, and tufA markers. No detectable genetic variability in U. lactuca samples was found throughout the research period. A quantitative examination of the lipid and FA content in U. lactuca in different harvest seasons revealed that the maximum content of lipids was in the summer, and that of polyunsaturated fatty acids (PUFAs) was in the winter. The PUFA profile included eicosapentaenoic acid, docosapentaenoic acid, docosahexaenoic acid, n-3, and n-6, where the n-6/n-3 ratio was comparable with the desired range for a balanced nutritional diet.

Herbal Emulgel Containing Azadirachta indica (Neem) and Nigella Sativa L. (Black Cumin) Oils in Wound Management: Preclinical Investigations

Abstract Context: In wound management, traditional use of plants has received attention by the scientific community, as traditional medicines are a valuable source of affordable, comprehensive medical care. Azadirachta indica A. Juss (Neem) and Nigella sativa Linn (Black cumin) are well known versatile medicinal plants with wide spectrum of biological activity. Methods: This study was undertaken to evaluate the wound healing activity of neem oil (NO) and black cumin oil (BCO) in rats. The oils were standardized using standard procedures. Gas chromatography mass spectrometry analysis and high performance thin layer chromatography fingerprinting of oils were carried out to identify major phytoconstituents present in the oils. The oils were suitably incorporated in carbopol based emulgel formulation, evaluated for physicochemical parameters and stability. Results: The wound healing potential assessed by the measurement of wound contraction and histopathology studies in excision and burn wound models, demonstrated comparable efficacy with standard nano crystalline silver gel (0.002% w/w). This may be attributed to the presence of phytoconstituents such as nimbidin and thymoquinone present in selected oils. Polyunsaturated fatty acid profile of BCO may be responsible for stimulating the release of vascular endothelial growth factor, which plays a significant role in accelerating wound healing process. Conclusion: Topical carbopol 934 base emulgel containing natural oils such as BCO and NO have been successfully prepared for wound management. However, further studies to establish the mechanistic aspects of wound healing needs to be undertaken.

Organic and Inorganic Selenium Compounds Affected Lipidomic Profile of Spleen of Lambs Fed with Diets Enriched in Carnosic Acid and Fish Oil.

The purpose of our study was to investigate the effect of 0.35 mg Se/kg basal diet (BD) (Se as sodium selenate (Se6) and yeast rich in seleno-methionine (SeYe)) and 0.1% carnosic acid (CA) supplementation to the diet containing 1% fish oil (F-O) and 2% rapeseed oil (R-O) on the contents of fatty acids (FA), malondialdehyde (MDA), tocopherols (Ts), and total cholesterol (TCh) in lambs' spleens. A total of 24 male lambs (4 groups per 6 animals) have been fed: the control diet-the basal diet (BD) enriched in F-O and R-O; the CA diet-BD enriched in F-O, R-O, and CA; the SeYeCA diet-BD enriched in F-O, R-O, CA, and SeYe; the Se6CA diet-BD enriched in F-O, R-O, CA, and Se6. Dietary modifications affected the profiles of saturated (SFA), monounsaturated (MUFA), and polyunsaturated (PUFA) fatty acids in spleens. The SeYeCA and Se6CA diets increased the docosapentaenoic acid preference in Δ4-desaturase; hence, a higher content of docosahexaenoic acid was found in the spleens of SeYe- or Se6-treated lambs than in spleens of animals receiving the CA and control diets. The SeYeCA and Se6CA diets increased the concentration ratio of n-3long-chain PUFA (n-3LPUFA) to FA (n-3LPUFA/FA) in spleens compared to the control and CA diets. The content of n-3PUFA was higher in the spleens of Se6 treated lambs than in spleens of animals receiving the SeYeCA, CA, and control diets. The Se6CA diet increased the content of c9t11CLA in the spleen compared to the control, CA, and SeYeCA diets. Experimental diets reduced the level of atherogenic FA, the content ratios of n-6PUFA/n-3PUFA and n-6LPUFA/n-3LPUFA, and improved the content ratio of MUFA/FA and the value of the hypocholesterolemic/hypercholesterolemic FA ratio in the spleen in comparison with the control diet. The experimental diets supplemented with SeYe or Se6 increased levels of TCh and Ts in spleens in comparison with the CA and control CA diets. The present studies documented that Se6, SeYe, and CA influenced the metabolism of FA, Ts, and cholesterol in spleens.

Compositional and nutritional evaluation of viscera from commercially harvested wild-caught Australian abalones (Haliotis spp.)

Discarded abalone viscera accounts for 25–42 % weight of total abalone waste and represents a cost-burden to producers. Previous research has identified these discarded abalone viscera as having the potential for pharmaceutical, nutraceutical and therapeutical outcomes, which have not been investigated in Australian varieties. Thus, comprehensive nutritional evaluation was conducted on the viscera of four commercially harvested wild-caught abalone in Australia; roe's abalone (Haliotis roei), greenlip abalone (Haliotis laevigata), brownlip abalone (Haliotis rubra conicopora), and blacklip abalone (Haliotis rubra rubra) collected from various locations and processors. Proximate composition, amino acid, fatty acid and protein and fat algorithmic quality evaluation were investigated. Protein and fat quality evaluation demonstrated the opportunity for utilizing abalone viscera to potentially improve the health status of aging populations, as well as exercise performance. Such evaluations included high essential amino acid index (EAAI) (81–85), predicted biological value (p-BV) (77–81) and predicted protein efficiency ratio (p-PER) (2.44–2.48). Samples were shown to have a unique docosapentaenoic acid (DPA) and arachidonic acid (ARA)-dominated polyunsaturated fatty acid (PUFA) profile leading to a favorable index of atherogenicity (IA), index of thrombogenicity (IT), health-promoting index (HPI), and hypocholesterolemic/hypercholesterolemic (HH) values (0.95–1.36, 0.42–0.76, 0.74–1.05, 1.02–1.56). Challenges to valorisation in maintaining product consistency were identified with the noted variation in proximate composition (moisture: 72.96–79.97 %, protein: 55.82–68.04 % carbohydrates: 9.96–28.82 %, ash: 10.02–16.75 %, fat: 3.12–13.37 %). Multi-categorical regression identified external factors predominantly determine compositional results. The exception was amino acids characterization which remained consistent within and between species. This study provided an arching overview of the opportunities and challenges in utilizing abalone processing waste, as well as identifying future research directions in commercialization of viscera products. Such directions may include simultaneous hydrolytic recovery of macronutrients.

The association between human milk fatty acid composition in mothers with an elevated body mass index and infant growth changes

Few studies have investigated alternations in human milk polyunsaturated fatty acid (PUFA) composition in the context of maternal obesity and its effects on infant growth trajectories. This study explored whether maternal weight status and breastfeeding type influence human milk FA composition and infant anthropometry during the first six months of life. Mother-infant dyads were enrolled from the Prediction of Allergies in Taiwanese Children birth cohort study. Data concerning maternal pre-pregnancy weight, infants' breastfeeding practices, and anthropometric data were obtained regularly. We identified and compared between the composition of 30 FAs in the colostrum and 2-month milk, respectively, in obese/overweight (OB/OW) and normal-weight (NW) mothers. Multiple linear regression analyses were performed to determine the association between PUFA composition at different lactation stages and infant anthropometric parameter changes and to identify the independent variables for body mass index (BMI) z-scores by six months of age. We included 338 mother-infant dyads (OB/OW mothers, 16.9%). OB/OW mothers exhibited lower total n-3 PUFAs (P=0.035), higher ratios of arachidonic acid (C20:4n-6)/eicosapentaenoic acid (C20:5n-3)+docosahexaenoic acid (C22:6n-3), and n-6/n-3 PUFA in colostrum (P=0.037 and 0.011, respectively), and their offspring had higher body weight and BMI z-scores. Nevertheless, no PUFA composition or n-6/n-3 PUFA ratios in colostrum and 2-month milk were associated with anthropometric parameter changes by age 6 months. Infant birth weight z-scores were independently associated with BMI outcomes at age 6 months (adjusted β=0.16, 95% confidence interval (0.05-0.35), P=0.010) CONCLUSION: Neither n-3 nor n-6 PUFA profiles nor n-6/n-3 PUFA ratios at different lactation stages were found to be associated with anthropometric changes by age 6 months, suggesting that human milk PUFA composition may not be an important determinant of early infant growth trajectories.

Localization and expression of phospholipase A2 and polyunsaturated fatty acid profile in the testis tissues of Hu sheep

The fatty acid content and the localization and expression of phospholipase A2 (PLA2) in the testis of Hu sheep were investigated. A total of 18 six-month-old Hu sheep were divided into small group (S, with left testis weight < 50 g), medium group (M, with left testis weight among 90–110 g), and large group (L, with left testis weight >160 g), which had six individuals each. The expression of PLA2 in testicular tissues of different sizes was analyzed by immunohistochemistry, RT-qPCR, and Western blot. The fatty acid profile was detected by gas chromatography. Immunohistochemical labeling determined that PLA2 protein was expressed in the Leydig and Sertoli cells of testis, and the immunohistochemical average optional density in the S group was significantly greater than the L group (P < 0.05). RT-qPCR and Western blot analysis showed that PLA2 in the S group was greater than that in the L group (P < 0.05). Docosahexaenoic acid, ω-3 polyunsaturated fatty acid (PUFA), and total PUFA content in the testis of the L group were significantly less than those of the S and M groups (P < 0.01). This study showed that PLA2 content in the S group was greater than that in the L group.

Loss of function mutations at the tomato SSI2 locus impair plant growth and development by altering the fatty acid desaturation pathway.

The stearoyl-ACP desaturase (SACPD) is a key enzyme in the regulation of saturated to unsaturated fatty acid ratio, playing a crucial role in regulating membrane stability and fluidity, as well as photosynthesis efficiency, which makes it an important research focus in crop species. This study reports the characterization and molecular cloning of pale dwarf (pad), a new tomato (Solanum lycopersicum L.) T-DNA recessive mutant, which exhibits a dwarf and chlorotic phenotype. Functional studies of the T-DNA tagged gene were conducted, including phylogenetic analysis, expression and metabolomic analyses, and generation of CRISPR/Cas9 knockout lines. The cloning of T-DNA flanking genomic sequences and a co-segregation analysis found the pad phenotype was caused by a T-DNA insertion disrupting the tomato homologue of the Arabidopsis SUPPRESSOR OF SALICYLIC ACID INSENSITIVITY 2 (SlSSI2), encoding a plastid localized isoform of SACPD. The phenotype of CRISPR/Cas9 SlSSI2 knockout lines confirmed that the morphological abnormalities in pad plants were due to SlSSI2 loss of function. Functional, metabolomic and expression analyses proved that SlSSI2 disruption causes deficiencies in 18:1 fatty acid desaturation and leads to diminished jasmonic acid (JA) content and increased salicylic acid (SA) levels. Overall, these results proved that SSI2 plays a crucial role in the regulation of polyunsaturated fatty acid profiles in tomato, and revealed that SlSSI2 loss of function results in an inhibited JA-responsive signalling pathway and a constitutively activated SA-mediated defence signalling response. This study lays the foundation for further research on tomato SACPDs and their role in plant performance and fitness.

The effect of teff (Eragrostis tef) hay inclusion on feed intake, digestibility, and milk production in dairy cows

Teff (Eragrostis tef) is a drought-tolerant, multi-harvest, high-quality summer forage crop. We conducted a study aiming at assessing the effect of replacing wheat hay with teff hay in diets on the feed intake, digestibility, and lactational performance of dairy cows. Thirty-four multiparous (≥3rd parity) Israeli Holstein Friesian dairy cows averaging (± SD) 182 days in milk ± 8 days in milk, 45 kg/d ± 4.8 kg/d of milk yield, and a body weight of 647.1 kg ± 51 kg at the beginning of the study were recruited to a 6-week feeding trial. Cows were randomly divided into two balanced groups based on parity, days in milk, and milk yield. Cows were subjected to two low-roughage dietary treatments (~30% roughage): a control wheat hay-based diet and a teff hay-based diet. Production performances, dry matter intake, and nutrient digestibility were measured. Milk samples were analyzed for their composition and fatty acids profile. Blood samples were used to measure metabolite concentrations. The statistical model included fixed effects of dietary treatments, time, and random effects of cows nested in treatment. Production data and feed intake were analyzed as repeated measures using a covariance structure. Dietary treatments did not affect dry matter intake (26 kg/d). However, the teff-fed cows demonstrated higher crude protein digestibility than control cows (61.9% vs. 59.2%). Dietary teff inclusion increased milk yield by 1.5 kg/d. Polyunsaturated fatty acids and omega-3 fatty acids profiles in milk were greater in the teff cows than in the control cows (4.77 g/100 g vs. 4.36 g/100 g and 3.71 g/100 g vs. 3.43 g/100 g, respectively). Non-esterified fatty acids, beta-hydroxybutyrate, and blood urea nitrogen concentrations in circulation were higher in the control group than in the teff group. The acetic-to-propionic-acid ratio in the rumen fluid was higher in control cows than in teff cows (2.90 vs. 2.43). However, the ruminal ammonia-N concentration was higher in the teff cows than in the control cows (18.5 mg/dL vs. 15.8 mg/dL). In conclusion, teff hay inclusion in the rations of high-producing dairy cows increased milk yield, which could be attributed to improved crude protein digestibility and energy partition to production.

Correlations between omega-3 fatty acids and inflammatory/glial abnormalities: the involvement of the membrane and neurotransmitter dysfunction in schizophrenia.

Macrophages or T-lymphocytes triggered inflammation and, consequently, activated glial cells may contribute to neuroinflammation and neurotransmitter dysfunction in schizophrenia (SZ), while omega(n)-3 polyunsaturated fatty acids (PUFAs) can attenuate some SZ symptoms through anti-inflammatory effects. However, the correlations between macrophage/T-lymphocyte-produced cytokines and glia phenotypes, between inflammatory status and PUFAs composition, between cytokines and neurotransmitter function, and between n-3 PUFAs and neurotransmitter abnormality in SZ are unclear. Changes in T-helper (h) patterns, peripheral macrophage/glial markers, PUFAs profile, membrane fluidity, and neurotransmitter functions were evaluated in SZ patients (n = 50) and healthy controls (n = 30) using ELISA, gas chromatography, fluorescence anisotropy techniques, and HPLC, respectively. Compared to the control, blood lymphocyte proliferation, the concentration of macrophage/microglia phenotype M1 markers, including cytokines IL-1β, TNF-α (Th1) and IL-6 (Th2), and astrocyte phenotype A1 marker S100β was significantly increased, while IL-17 and n-3 PUFAs contents, n-3/n-6 ratio, and membrane fluidity (FLU) were significantly decreased in SZ. Moreover, increased DA and HVA, decreased 5-HT and NE, and their metabolites appeared in SZ. Moreover, negative correlations between IL-6 and A2 marker Brain-Derived Neurotrophic Factor (BDNF) or n-3 PUFAs EPA and between IL-1β and FLU or 5HIAA, while positive correlations between EPA and 5-HIAA and between FLU and DHA were found in SZ. These findings showed (1) no clear Th pattern, but pro-inflammatory-dominant immunity occurred; (2) the pro-inflammatory pattern may result in the activated microglia M1 and astrocyte A1 phenotype; and (3) increased pro-inflammatory cytokines were related to decreased n-3 PUFA and decreased membrane fluidity and dysfunctional neurotransmitter systems in SZ.

The roles of soybean lecithin in aquafeed: a crucial need and update.

Soybean lecithin is extensively used as the dietary supplementation of phospholipids in animal production. Soybean lecithin plays significant roles in aquafeed as growth promoter, feed enhancer, immunity modulator and antioxidant activity stimulator for aquaculture species. Besides, soybean lecithin is also reported to help aquaculture species being resilient to physical and chemical stressors. In this review, common sources, chemical structure and mode of action of lecithin, with highlight on soybean lecithin application in aquaculture over four-decadal studies published between 1983 and 2023, were evaluated and summarized. By far, soybean lecithin is best-known for its beneficial effects, availability yet cost-effective for aquafeed formulation. Findings from this review also demonstrate that although nutritional profile of long-chain polyunsaturated fatty acids and phosphatidylcholine from egg yolk and marine sources are superior to those from plant sources such as soybean, it is rather costly for sustainable application in aquafeed formulation. Moreover, commercially available products that incorporate soybean lecithin with other feed additives are promising to boost aquaculture production. Overall, effects of soybean lecithin supplementation are well-recognized on larval and juvenile of aquaculture species which having limited ability to biosynthesis phospholipids de novo, and correspondingly attribute to phospholipid, a primary component of soybean lecithin, that is essential for rapid growth during early stages development. In addition, soybean lecithin supplementation plays a distinguish role in stimulating maturation of gonadal development in the adults, especially for crustaceans.

The exploration of neuroinflammatory mechanism by which CRHR2 deficiency induced anxiety disorder

Inflammation stimulates the hypothalamic-pituitary adrenal (HPA) axis and triggers glial neuroinflammatory phenotypes, which reduces monoamine neurotransmitters by activating indoleamine 2,3-dioxygenase enzyme. These changes can induce psychiatric diseases, including anxiety. Corticotropin releasing hormone receptor 2 (CRHR2) in the HPA axis is involved in the etiology of anxiety. Omega(n)-3 polyunsaturated fatty acids (PUFAs) can attenuate anxiety through anti-inflammation and HPA axis modulation. However, the underlying molecular mechanism by CRHR2 modulates anxiety and its correlation with neuroinflammation remain unclear. Here, we first constructed a crhr2 zebrafish mutant line, and evaluated anxiety-like behaviors, gene expression associated with the HPA axis, neuroinflammatory response, neurotransmitters, and PUFAs profile in crhr2+/+ and crhr2−/− zebrafish. The crhr2 deficiency decreased cortisol levels and up-regulated crhr1 and down-regulated crhb, crhbp, ucn3l and proopiomelanocortin a (pomc a) in zebrafish. Interestingly, a significant increase in the neuroinflammatory markers, translocator protein (TSPO) and the activation of microglia M1 phenotype (CD11b) were found in crhr2−/− zebrafish. As a consequence, the expression of granulocyte-macrophage colony-stimulating factor, pro-inflammatory cytokines vascular endothelial growth factor, and astrocyte A1 phenotype c3 were up-regulated. While microglia anti-inflammatory phenotype (CD206), central anti-inflammatory cytokine interleukin-4, arginase-1, and transforming growth factor-β were downregulated. In parallel, crhr2-deficient zebrafish showed an upregulation of vdac1 protein, a TSPO ligand, and its downstream caspase-3. Furthermore, 5-HT/5-HIAA ratio was decreased and n-3 PUFAs deficiency was identified in crhr2−/− zebrafish. In conclusion, anxiety-like behavior displayed by crhr2-deficient zebrafish may be caused by the HPA axis dysfunction and enhanced neuroinflammation, which resulted in n-3 PUFAs and monoamine neurotransmitter reductions.

The impact of varying EPA:DHA ratio on Atlantic salmon health and welfare

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are essential fatty acids (EFA) vital for Atlantic salmon health, growth performance, and product quality. Yet, DHA and especially EPA are in short supply as ingredients for aquafeeds. Whilst the role of EFA in salmonid nutrition has been well studied, clear guidelines for aquaculture nutrition practitioners are still missing. This article addresses this gap by testing different EPA:DHA ratios (0.15, 0.55, and 0.98) when these two EFA represent at least 10% of the total pool of fatty acids in aquafeeds. Grow-out trials revealed no differences in zootechnical performance between fish fed the different diets during the initial eight weeks before vaccination challenge, nor on the subsequent three weeks post-vaccination for fish truly vaccinated or sham vaccinated (used as control groups for each of the three diets tested). Nonetheless, the FCR of vaccinated fish was significantly higher than sham vaccinated conspecifics, but diet yielded no significant effect. The expression of most genes screened (e.g., Elongation Factor 1α (Elf-1α), Interleukin 10 (IL10), Interleukin 8 (IL8), Tumor Necrosis Factor (TNFα)) was not significantly affected by vaccination or diet, while Viperine and Mx genes were upregulated in sham vaccinated fish fed the experimental diet with an EPA:DHA ratio of 0.55. The fatty acid composition of head kidney was affected by diet, namely EPA, but not DHA. The fatty acid profile of white muscle was also significantly affected by diet, with contrasting results for EPA and DHA; EPA content was higher for fish fed diets with higher EPA:DHA ratios and DHA levels were significantly higher (peaking at 16% of the total pool of fatty acids) when fish were provided with the diet featuring the lowest EPA:DHA ratio (0.15). Interestingly, fish fed the diet with the highest EPA:DHA ratio showed a lower number of wounded fish at the end of the grow-out period post-vaccination. Despite the reduction was not statistically significant, given the severe impact of wounded fish on salmon farming productivity, our results indicate that the partial replacement of fish oil with algal oil in salmon feed contributed to achieving a balanced EPA:DHA ratio, an adequate profile of Omega-3 long chain polyunsaturated fatty acids and improved the overall health and welfare of fish. This approach creates the opportunity to increase the productivity of fish farming operations and foster a more sustainable growth of the aquaculture industry.

Association between Polyunsaturated Fatty Acid Profile and Bronchial Inflammation in Bronchiolitis Obliterans.

Bronchiolitis obliterans (BO) is a chronic lung disease, which occurs after an insult to the lower airways, in particular after airway infections or after stem cell transplantation, and which results in persistent inflammation. N-3 and n-6 polyunsaturated fatty acids (PUFA) have been shown to influence the inflammatory processes in chronic inflammatory conditions. Since BO is maintained by persistent pulmonary inflammation, a disbalanced n-6/n-3 fatty acid profile could support the inflammatory process in patients with BO and therefore, could become an approach to new therapeutic options. Twenty-five patients with BO (age: 13; 7-39) and 26 healthy controls (age: 19; 7-31) participated in the study. Lung function (forced viral capacity (FVC), forced expiratory volume 1 (FEV1), residual volume (RV)), and lung clearance index (LCI) were measured. Induced sputum was analyzed for cytology and cytokine levels (IL-1ß, IL-6, IL-8, TNF-α) using cytometric bead array (CBA). The PUFA profile was determined in the serum and induced sputum by gas chromatography. Patients presented with significantly lower FVC and FEV1 as well as higher RV and LCI measurements compared to the control group. Apart from a massive airway inflammation indicated by elevated numbers of total cells and neutrophils, the CBA analysis showed significantly increased levels of IL-1β, IL-6, and IL-8. The analysis of PUFA in sputum and serum revealed a significant difference in the ratio between the n-6 PUFA arachidonic acid (AA) and the n-3 PUFA docosahexaenoic acid (DHA) (AA : DHA). Furthermore, the AA : DHA ratio significantly correlated with the inflammatory cytokines in induced sputum. Lung function in BO is significantly impaired and associated with uncontrolled neutrophil-dominated airway inflammation. Furthermore, the imbalance in the AA/DHA ratio in favor of n-6 PUFA demonstrates a pro-inflammatory microenvironment in the cell membrane, which correlates with the inflammatory cytokines in induced sputum and might be an option for an anti-inflammatory therapy in BO.

Performance, milk fatty acid profile and oxidative status of lactating small ruminants supplemented with microalgae: A meta-analysis

Microalgae are considered an effective strategy to improve the polyunsaturated fatty acid profile of ruminant milk. This meta-analysis aimed to evaluate the effects of dietary supplementation with microalgae (MIAs) on milk yield, oxidative status, and milk quality of lactating small ruminants. The data used were obtained from 20 peer-reviewed scientific articles. The weighted mean difference between experimental treatments (diets added with MIAs) and control treatments (diets without MIAs) was evaluated using the random-effects meta-analysis model. Higher dry matter intake and milk yield were observed in response to MIAs supplementation (P < 0.05). In addition, MIAs supplementation increased (P < 0.05) the contents of conjugated linoleic, α-linolenic, γ-linolenic, eicosapentaenoic, docosahexaenoic, total polyunsaturated, and total omega-3 fatty acids in milk. In blood plasma, higher (P < 0.05) concentrations of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase were observed in response to MIAs supplementation. In milk, MIAs supplementation decreased fat content (P < 0.001) and increased SOD and CAT content (P < 0.05). In conclusion, the dietary inclusion of MIAs could be used as a nutritional strategy to improve the performance and fatty acid profile in the milk of small ruminants. Furthermore, MIAs supplementation could be used to improve the oxidative status of blood plasma and milk of lactating small ruminants.

The Effect of Crackers Enriched with Camelina Sativa Oil on Omega-3 Serum Fatty Acid Composition in Older Adults: A Randomized Placebo-Controlled Pilot Trial

BackgroundCamelina sativa oil is one of the richest dietary sources of omega-3, with polyunsaturated fatty acids amounts of over 50%, linolenic acid content of around 40–45%, and linoleic acid of about 15%. Moreover, this oil is a valuable source of antioxidants which provide oxidative stability. All those features raise interest in considering Camelina oil as an alternative and sustainable oil source providing stable omega-3-rich emulsions for functional food production.ObjectivesThe present study aimed to investigate the effects of Camelina oil-enriched crackers on serum omega-3 concentration, inflammatory markers and serum lipid profile.DesignRandomized placebo-controlled pilot trial. Setting: Research and Development Center (Complife Italia s.r.l.).ParticipantsSixty-six free-living older volunteers (aged≥65 years).InterventionOlder adults were enrolled and randomly assigned to one of two groups: the camelina group or the placebo group. Subjects consumed daily 35 g of crackers (Camelina enriched crackers or placebo ones) twice daily for 12 weeks.MeasurementsSerum polyunsaturated fatty acid profile, inflammatory status and serum lipid panel parameters were recorded pre and post-intervention.ResultsIn the camelina group, alpha-linolenic acid serum concentration was significantly higher (p<0.01) compared to the placebo group at the end of the study. Concerning inflammatory plasma markers, a significant mean pro-inflammatory interleukin-18 plasma concentration decrease in the placebo group compared to the camelina one was observed (p<0.05). No significant differences in other mean inflammatory markers concentrations post-intervention were noted in either group. Lastly, examining the change in lipid profile, it is noteworthy that a higher reduction of total cholesterol, low-density lipoprotein and triglycerides in the camelina group postintervention, despite the lack of statistical significance.ConclusionCamelina oil significantly elevated the serum alpha-linolenic acid concentration with no significant changes in inflammatory markers and lipid profile.