Tissue Lipid Composition Research Articles

N-Stearoylethanolamine Exerts Cardioprotective Effects in Old Rats.

Aging is associated with the slowing down of metabolic processes, diminished physiological processes, changes in hormonal activity and increasing exposure to oxidative stress factors and chronic inflammation. The endocannabinoid system (ECS) is a major signaling network that plays a pro-homeostatic role in the central and peripheral organs of the human body. A class of minor lipids, N-acylethanolamines (NAEs), which do not activate cannabinoid receptors, except for anandamide, but can potentiate the action of endocannabinoids and have a wide spectrum of biological activity and significant adaptogenic potential, belongs to ECS. The results of different studies over the past decades have established the protective effect of NAE on many pathological conditions. This study aimed to investigate the cardioprotective effects of C18:0 NAE- N-stearoylethanolamine (NSE) in aged rats. In this study, we focused on investigating the effects of C18:0 NAE- N-stearoylethanolamine (NSE) on the intensity of oxidative/ nitrosative stress, antioxidant potential, lipoprotein profile and inflammation markers of blood plasma, phospholipid composition and age-related morphological changes of old rat heart tissues. The study was conducted on Sprague Dawley male laboratory rats. The three groups of rats were involved in the study design. The first group consisted of young rats aged 4 months (n=10). The second (n=10) and third (n=10) groups included old rats aged of 18 months. Rats from the third group were administered a per os aqueous suspension of NSE at a dose of 50 mg/kg of body weight daily for 10 days. All groups of rats were kept on a standard vivarium diet. The blood plasma, serum, and heart of rats were used for biochemical and histological analysis. The cardioprotective effect of N-stearoylethanolamine in old rats was established, which was expressed in the normalization of the antioxidant system condition and the level of proinflammatory cytokines, positive modulation of blood plasma and lipoprotein profile, normalization of heart tissue lipid composition, and significant reduction in age-related myocardium morphological changes. The revealed effects of N-stearoylethanolamine can become the basis for developing a new drug for use in complex therapy to improve the quality of life of older people.

Investigating the influence of molybdenum disulfide quantum dots coated with DSPE-PEG-TPP on molecular structures of liver lipids and proteins: An in vivo study

Molybdenum disulfide (MoS2) quantum dots (QDs) based therapeutic approaches hold great promise for biomedical applications, necessitating a thorough evaluation of their potential effects on biological systems. In this study, we systematically investigated the impact of MoS2 QDs coated with 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[amino(polyethyleneglycol)-2000](DPSE-PEG) linked with (3-carboxypropyl)triphenyl-phosphonium-bromide (TPP) on molecular structures of hepatic tissue lipids and proteins through a multifaceted analysis. The DSPE-PEG-TPP-MoS2 QDs were prepared and administered to the mice daily for 7 weeks. Liver tissues were subjected to a comprehensive examination using various techniques, including Fourier-transform infrared (FTIR) spectroscopy, UV–vis spectroscopy, and liver function tests. FTIR revealed subtle changes in the lipid composition of liver tissues, indicating potential modifications in the cell membrane structure. Also, the (CH stretching and amides I and II regions) analysis unveiled tiny alterations in lipid chain length and fluidity without changes in the protein structures, suggesting a minor influence of DSPE-PEG-TPP-MoS2 QDs on the liver’s cellular membrane and no effect on the protein structures. Further scrutiny using UV–vis spectroscopy demonstrated that DSPE-PEG-TPP-MoS2 QDs had no discernible impact on the absorbance intensities of aromatic amino acids and the Soret band. This observation implies that the treatment with SPE-PEG-TPP-MoS2 QDs did not induce significant alterations in helical conformation or the microenvironment surrounding prosthetic groups in liver tissues. The liver function tests, including ALP, ALT, AST, and BIL levels, revealed no statistically significant changes in these key biomarkers despite minor fluctuations in their values, indicating a lack of significant liver dysfunction. This study provides a detailed understanding of the effects of DSPE-PEG-TPP-MoS2 QDs on hepatic lipids and proteins, offering valuable insights into the biocompatibility and limited impact on the molecular and functional aspects of the liver tissue. These findings could be essential for the application of MoS2 QDs-based therapies.

Variable effects of periprostatic adipose tissue on prostate cancer cells: Role of adipose tissue lipid composition and cancer cells related factors.

Periprostatic adipose tissue (PPAT) is likely to modulate prostate cancer (PCa) progression. We analyzed the variations in the effect of PPAT on cancer cells, according to its fatty acid (FA) composition and tumor characteristics. The expression of markers of aggressiveness Ki67 and Zeb1, and epigenetic marks that could be modified during PCa progression, was analyzed by immunohistochemistry on a tissue-micro-array containing 59 pT3 PCa, including intra-prostatic areas and extra-prostatic foci in contact with PPAT belonging to the same tumor. In addition, we cocultivated PC3 and LNCaP cell lines with PPAT, which were then analyzed for FA composition. Although the contact between PPAT and cancer cells led overall to an increase in Ki67 and Zeb1, and a decrease in the epigenetic marks 5MC, 5HMC, and H3K27ac, these effects were highly heterogeneous. Increased proliferation in extra-prostatic areas was associated with the international society of uropathology score. PC3 and LNCaP cocultures with PPAT led to increased Ki67, Zeb1 and H3K27me3, but only for PPAT associated with aggressive PCa. PC3 proliferation was correlated with high 20.2 n-6 and low 20.5n-3 in PPAT. These results suggest that the effects of PPAT on cancer cells may depend on both PCa characteristics and PPAT composition, and could lead to propose nutritional supplementation.

Effects of Replacing Fishmeal with Algal Biomass (Pavlova sp. 459) on Membrane Lipid Composition of Atlantic Salmon (Salmo salar) Parr Muscle and Liver Tissues

A 12-week feeding trial examined the dietary impact of replacing fishmeal (FM) with algal biomass (AB) derived from Pavlova sp. strain CCMP459 (Pav459) in Atlantic salmon diets. Three distinct diets were formulated: a control diet featuring 20% FM and 7% fish oil (FO), an experimental diet incorporating a 50:50 blend of FM and AB Pav459 and reduced FO (10% FM; 4.5% FO; 10% AB), and a second experimental diet with full replacement of FM with AB Pav459 and further reduction in FO (1.75% FO; 20% AB). Replacing FM with AB Pav459 showed no significant effects on the growth performance of Atlantic salmon. Fish across all diets exhibited growth exceeding 200% from their initial weight. Analysis of total lipid content after the 12-week trial revealed no significant differences among the diets. However, individual proportions of omega-3 (ω3) and omega-6 (ω6) fatty acids varied. Fatty acid profiling in muscle and liver tissues showed distinct compositions reflective of dietary treatments. Linoleic acid (LA) and α-linolenic acid (ALA) exhibited higher proportions in total fatty acids than in membrane lipids. Docosahexaenoic acid (DHA) emerged as the predominant fatty acid in the membranes of both liver and muscle tissues. Furthermore, an analysis of sterol composition in Pavlova and salmon muscle tissue showed the presence of important sterols, including conventionally animal-associated cholesterol. This emphasizes the suitability of microorganisms, such as Pav459, for synthesizing diverse nutrients. Stable isotope analysis demonstrated direct incorporation of eicosapentaenoic acid (EPA) and DHA from diets into salmon tissues. Notably, minimal biosynthesis from the precursor ALA was observed, reaffirming the utility of Pav459-derived fatty acids. The EPA+DHA proportions in the fillet consistently met daily human consumption requirements across all dietary conditions, supporting the use of Pav459 algal biomass as an alternative to FM.

Serum opacity factor normalizes erythrocyte morphology in Scarb1−/− mice in an HDL-free cholesterol-dependent way

Compared with WT mice, HDL receptor-deficient (Scarb1−/−) mice have higher plasma levels of free cholesterol (FC)-rich HDL and exhibit multiple pathologies associated with a high mol% FC in ovaries, platelets, and erythrocytes, which are reversed by lowering HDL. Bacterial serum opacity factor (SOF) catalyzes the opacification of plasma by targeting and quantitatively converting HDL to neo HDL (HDL remnant), a cholesterol ester-rich microemulsion, and lipid-free APOA1. SOF delivery with an adeno-associated virus (AAVSOF) constitutively lowers plasma HDL-FC and reverses female infertility in Scarb1−/− mice in an HDL-dependent way. We tested whether AAVSOF delivery to Scarb1−/− mice will normalize erythrocyte morphology in an HDL-FC-dependent way. We determined erythrocyte morphology and FC content (mol%) in three groups—WT, untreated Scarb1−/− (control), and Scarb1−/− mice receiving AAVSOF—and correlated these with their respective HDL-mol% FC. Plasma-, HDL-, and tissue-lipid compositions were also determined. Plasma- and HDL-mol% FC positively correlated across all groups. Among Scarb1−/− mice, AAVSOF treatment normalized reticulocyte number, erythrocyte morphology, and erythrocyte-mol% FC. Erythrocyte-mol% FC positively correlated with HDL-mol% FC and with both the number of reticulocytes and abnormal erythrocytes. AAVSOF treatment also reduced FC of extravascular tissues to a lesser extent. HDL-FC spontaneously transfers from plasma HDL to cell membranes. AAVSOF treatment lowers erythrocyte-FC and normalizes erythrocyte morphology and lipid composition by reducing HDL-mol% FC.

The Lipid Profile of the Tissues of the Gray Whale (<i>Eschrichtius robustus</i>): to the Relationship of Composition of Lipids and Their Physiological and Biochemical Role in Maintaining Tissue Function

A study was made of the composition of lipids in different tissues of gray whales Eschrichtius robustus, and the lipid profiles of tissues with different functional loads were compared. Five types of tissues (skin, muscle, liver, outer and inner layers of fat) were collected from seventeen individuals of eastern gray whales during the permitted aboriginal fishing in the village. Lorino of the Chukotka Autonomous Okrug in the summer of 2020. For all of the listed tissues, the composition of total lipids and their individual lipid classes was studied by high-performance thin-layer chromatography (HPTLC), the identification and description of lipid profiles of different types of tissues was carried out, which made it possible to identify their general and specific features of lipid metabolism according to the studied parameters. Comparative analysis of lipid profiles of tissues revealed individual lipid classes that make the greatest contribution to discrimination between different tissues. Both the content of total lipids and individual lipid classes varied significantly in different tissues. At the same time, 93% of the differences between tissues are two functions that are most closely related to the content of metabolically associated diacylglycerols (DAG), monoacylglycerols (MAG), triacylglycerols (TAG) and waxes, mainly energetic lipids, in tissues. The paper discusses the relationship between the qualitative and quantitative composition of lipids and the functional load and the physiological role of tissues. The metabolic features of the accumulation and consumption of lipid classes during the feeding period were noted. The revealed differences in certain parameters of lipid metabolism of the outer and inner layers of fat are due to different metabolic activity of tissues and their function in the body, which, among other things, is provided by lipids.

Sterols, free fatty acids, and total fatty acid content in the massive Porites spp. corals cultured under different pCO2 and temperature treatments

Lipids may serve as energy reserves to support coral calcification, allow acclimation to higher temperatures, and are implicated in the control of CaCO3 precipitation. Here, we report the lipid composition of the soft tissues (including host and symbionts) of 7 massive Porites spp. coral colonies (4 × P. lutea and 3 × P. murrayensis), which were cultured under different pCO2 concentrations (180, 260, 400 and 750 µatm) and at two temperatures (25 ℃ and 28 ℃), below the thermal stress threshold. We report the fatty acid methyl esters (FAME), free fatty acid (FFA) to total fatty acid content, sterol and wax ester profiles, and identify two ketones (n-alkanone) and three long chain aldehyde (n-alkanal) derivatives. Increasing seawater temperature significantly increases the contributions of FFAs to the total lipids, of C18:2 and C20:0 to the total FFA pool, of C14:0 to total FAME, and of campesterol to total sterol. The temperature increase also reduces the contributions of unusual fatty acid derivatives to total lipids, of C14:0, C15:0, C16:0 and C17:0 saturated free fatty acids to total FFAs, and of C16:0 FA to total FAME. Fatty acids are implicated in the control of membrane structure fluidity and the observed changes may promote acclimation and thermostability as temperature varies. Seawater pCO2 has no significant effect on the composition of tissue lipids with the exception that the contribution of C14:0 FA to total lipid content is significantly lower at 180 µatm compared to 260 and 750 µatm. Decreased contribution of total sterols and unusual fatty acid derivatives and increased contribution of total FFAs to total lipids are observed in the fastest calcifying coral (a P. lutea specimen) compared to the other corals, under all pCO2 and temperature conditions. Although a rapid calcifier this genotype has been shown previously to exhibit pronounced abnormal changes in skeletal morphology in response to decreased seawater pCO2. Variations in tissue lipid composition between coral genotypes may influence their resilience to future climate change.

Effects of Replacement of Fish Oil with Microbial Oil (Schizochytrium sp. T18) on Membrane Lipid Composition of Atlantic Salmon Parr Muscle and Liver Tissues

A 16-week feeding trial was conducted to investigate effects of replacing dietary fish oil (FO) with docosahexaenoic acid (DHA)-rich microbial oil (MO) from Schizochytrium sp. (T18) on membrane lipid composition of Atlantic salmon parr liver and muscle tissues. Four nutritionally balanced diets were formulated with varying levels of FO, MO, and canola oil (CO), including a control diet with 20% FO, a secondary control diet with 10% FO and 10% CO, and two experimental diets that completely replaced FO with a low (5%) and high (10%) proportion of MO. No significant differences were observed in growth parameters (81–98 g; weight gain), total lipid class composition, and total sterol content among the dietary treatments. However, there were significant differences in the proportions of individual ꞷ3 and ꞷ6 fatty acids in both liver and muscle tissues, reflecting the different dietary treatments. Notably, the presence of low eicosapentaenoic acid (EPA) in the MO diets did not affect the growth performance of the fish, suggesting a lower requirement for EPA in the diet and a greater necessity for DHA. The results also showed that DHA was present in very high proportions in the cellular membrane, particularly in muscle tissue, with low levels of linoleic acid and alpha-linolenic acid. Overall, the findings suggest that MO derived from Schizochytrium sp. (T18) could be a potential substitute for FO in the diet of farmed Atlantic salmon.

Distribution, composition, and activity of airway-associated adipose tissue in the porcine lung.

Patients with comorbid asthma-obesity experience greater disease severity and are less responsive to therapy. We have previously reported adipose tissue within the airway wall that positively correlated with body mass index. Accumulation of biologically active adipose tissue may result in the local release of adipokines and disrupt large and small airway function depending on its anatomical distribution. This study therefore characterized airway-associated adipose tissue distribution, lipid composition, and adipokine activity in a porcine model. Airway segments were systematically dissected from different locations of the bronchial tree in inflation-fixed lungs. Cryosections were stained with hematoxylin and eosin (H&E) for airway morphology, oil red O to distinguish adipose tissue, and Nile blue A for lipid subtype delineation. Excised airway-associated adipose tissue was cultured for 72 h to quantify adipokine release using immunoassays. Results showed that airway-associated adipose tissue extended throughout the bronchial tree and occupied an area proportionally similar to airway smooth muscle within the wall area. Lipid composition consisted of pure neutral lipids (61.7 ± 3.5%), a mixture of neutral and acidic lipids (36.3 ± 3.4%), or pure acidic lipids (2.0 ± 0.8%). Following tissue culture, there was rapid release of IFN-γ, IL-1β, and TNF-α at 12 h. Maximum IL-4 and IL-10 release was at 24 and 48 h, and peak leptin release occurred between 48 and 72 h. These data extend previous findings and demonstrate that airway-associated adipose tissue is prevalent and biologically active within the bronchial tree, providing a local source of adipokines that may be a contributing factor in airway disease.

Exercise timing influences multi-tissue metabolome and skeletal muscle proteome profiles in type 2 diabetic patients – A randomized crossover trial

Aims/hypothesisMetabolic effects of exercise may partly depend on the time-of-day when exercise is performed. We tested the hypothesis that exercise timing affects the adaptations in multi-tissue metabolome and skeletal muscle proteome profiles in men with type 2 diabetes. MethodsMen fitting the inclusion (type 2 diabetes, age 45–68 years and body mass index 23–33 kg/m2) and exclusion criteria (insulin treatment, smoking, concurrent systemic disease, and regular exercise training) were included in a randomized crossover trial (n = 15). Participants included in this metabolomics and proteomics analysis fully completed all exercise sessions (n = 8). The trial consisted of two weeks of high-intensity interval training (HIT) (three sessions/week) either in the morning (08:00, n = 5) or afternoon (16:45, n = 3), a two-week wash-out period, and an additional two weeks of HIT at the opposing time. Participants and researchers were not blinded to group allocation. Blood, skeletal muscle and subcutaneous adipose tissue were obtained before the first, and after each training period. Broad-spectrum, untargeted proteomic analysis was performed on skeletal muscle, and metabolomic analysis was performed on all biosamples. Differential content was assessed by linear regression and pathway set enrichment analyses were performed. Coordinated metabolic changes across tissues were identified by Spearman correlation analysis. ResultsMetabolic and proteomic profiles remained stable after two weeks of HIT, and individual metabolites and proteins were not altered, irrespective of the time of day at which the training was performed. However, coordinated changes in relevant metabolic pathways and protein categories were identified. Morning and afternoon HIT similarly increased plasma diacylglycerols, skeletal muscle acyl-carnitines, and subcutaneous adipose tissue sphingomyelins and lysophospholipids. Acyl-carnitines were central to training-induced metabolic cross-talk across tissues. Plasma carbohydrates, via the penthose phosphate pathway, were increased and skeletal muscle lipids were decreased after morning compared to afternoon HIT. Skeletal muscle lipoproteins were higher, and mitochondrial complex III abundance was lower after morning compared to afternoon HIT. Conclusions/interpretationWe provide a comprehensive analysis of a multi-tissue metabolomic and skeletal muscle proteomic responses to training at different times of the day in men with type 2 diabetes. Increased circulating lipids and changes in adipose tissue lipid composition were common between morning and afternoon HIT. However, afternoon HIT increased skeletal muscle lipids and mitochondrial content to a greater degree than morning training. Thus, there is a diurnal component in the metabolomic and proteomic response to exercise in men with type 2 diabetes. The clinical relevance of this response warrants further investigation.

Lipid composition of oocytes and tissues of sturgeons depending on conditions of detention

Shortage of sturgeon spawners has led to the need for reservation and long-term detention of spawners, creation of their own brood stocks. The issues of assessing the functional state of producers and the reproductive products and offspring become topical. The wintering conditions of fish in cages at the natural course of temperatures negatively affect their physiological state. During this period, the fish actively move in the cages, but do not feed. The detention of sturgeon spawners in the pools with regulating the parameters of the aquatic environment makes it possible to stabilize the cycle of maturation of the gonads and increase the number of fish-producing females. The lipid composition of caviar affects its fish-breeding quality. The main components of sturgeon caviar fats are triglycerides and lipoid substances, which are represented by phospholipids that are actively involved in generative metabolism during the maturation of gonads. The main fraction of oocyte lipids is represented by triglycerides, whose level in the oocytes of fish from recirculating water installation (RWI) is higher in comparison with cage fish. It was found that sterlet oocyte lipids are mainly represented by triglycerides. Their concentration in the oocytes of fish kept in RWI is higher in comparison with fish kept in cages. Against the higher amount of triglycerides in fish roe from RWI, a decrease in the level of phospholipids and cholesterol was noted. The aging conditions of producers affect the composition of the main lipid fractions. As a result of the research, a relationship was established between the content of polyunsaturated fatty acids in the tissues of aquatic organ-isms and environmental conditions. The amount of saturated and monounsaturated fatty acids in the muscles of fish kept in RWI was higher than in the tissues of fish kept in cages. Increasing proportion of polyunsaturated fatty acids in the eggs of fish kept in cages indicates a fairly high utilization of monounsaturated fatty acids.

Dietary inclusion of a marine microalgae meal for Atlantic salmon (Salmo salar): Impact of Pavlova sp. 459 on growth performance and tissue lipid composition

An intact-cell meal produced from the marine microalga, Pavlova sp. CCMP459 (Pav459) cultivated in land-based enclosed photobioreactors, was investigated as a protein and lipid source in the diets for post-smolt Atlantic salmon (Salmo salar). The Pav459 meal contained 60.87% protein, 12.25% lipid, 2.86% EPA and 1.45% DHA. Growth performance and tissue fatty acid profiles of salmon (170.1 ± 23.9 g/fish initial weight) were evaluated after being fed test diets for 12 weeks containing either 10% (Low Pav) or 20% (High Pav) Pav459 meal; relative to a fish meal and fish oil-based control diet. No significant differences (P > 0.05) were found in salmon comparing dietary treatments for weight gain (271.3–279.6 g/fish), specific growth rate (1.2%/day), or feed conversion ratio (0.9 g feed/g gain). Salmon fed diets containing Pav459 meal had a slightly higher condition factor (1.3) than salmon fed the control diet (1.2). Liver DHA + EPA were significantly higher in salmon fed the control diet (5.1 mg/g) than salmon fed diets containing 10–20% Pav459 meal (3.4–3.5 mg/g). There were no significant differences observed in fillet muscle DHA, EPA, and most fatty acids among salmon fish diets containing 10–20% Pav459 meal compared to salmon fed the control diet. Overall, the results from this study indicate that Pav459 marine microalgae meal is a good candidate source of protein and essential n-3 LC-PUFA in diets for farmed Atlantic salmon.

Recent Advances in Studying Age-Associated Lipids Alterations and Dietary Interventions in Mammals.

Lipids are involved in a broad spectrum of canonical biological functions, from energy supply and storage by triacylglycerols to membrane formation by sphingolipids, phospholipids and glycolipids. Because of this wide range of functions, there is an overlap between age-associated processes and lipid pathways. Lipidome analysis revealed age-related changes in the lipid composition of various tissues in mice and humans, which were also influenced by diet and gender. Some changes in the lipid profile can be linked to the onset of age-related neurodegenerative diseases like Alzheimer’s disease. Furthermore, the excessive accumulation of lipid storage organelles, lipid droplets, has significant implications for the development of inflammaging and non-communicable age-related diseases. Dietary interventions such as caloric restriction, time-restrictive eating, and lipid supplementation have been shown to improve pertinent health metrics or even extend life span and thus modulate aging processes.

Lipidomic Profiling of Colorectal Lesions for Real-Time Tissue Recognition and Risk-Stratification Using Rapid Evaporative Ionization Mass Spectrometry.

Rapid evaporative ionization mass spectrometry (REIMS) is a metabolomic technique analyzing tissue metabolites, which can be applied intraoperatively in real-time. The objective of this study was to profile the lipid composition of colorectal tissues using REIMS, assessing its accuracy for real-time tissue recognition and risk-stratification. Metabolic dysregulation is a hallmark feature of carcinogenesis; however, it remains unknown if this can be leveraged for real-time clinical applications in colorectal disease. Patients undergoing colorectal resection were included, with carcinoma, adenoma and paired-normal mucosa sampled. Ex vivo analysis with REIMS was conducted using monopolar diathermy, with the aerosol aspirated into a Xevo G2S QToF mass spectrometer. Negatively charged ions over 600 to 1000 m/z were used for univariate and multivariate functions including linear discriminant analysis. A total of 161 patients were included, generating 1013 spectra. Unique lipidomic profiles exist for each tissue type, with REIMS differentiating samples of carcinoma, adenoma, and normal mucosa with 93.1% accuracy and 96.1% negative predictive value for carcinoma. Neoplasia (carcinoma or adenoma) could be predicted with 96.0% accuracy and 91.8% negative predictive value. Adenomas can be risk-stratified by grade of dysplasia with 93.5% accuracy, but not histological subtype. The structure of 61 lipid metabolites was identified, revealing that during colorectal carcinogenesis there is progressive increase in relative abundance of phosphatidylglycerols, sphingomyelins, and mono-unsaturated fatty acid-containing phospholipids. The colorectal lipidome can be sampled by REIMS and leveraged for accurate real-time tissue recognition, in addition to riskstratification of colorectal adenomas. Unique lipidomic features associated with carcinogenesis are described.

Lipidomic Profiling of Clinical Prostate Cancer Reveals Targetable Alterations in Membrane Lipid Composition.

Dysregulated lipid metabolism is a prominent feature of prostate cancer that is driven by androgen receptor (AR) signaling. Here we used quantitative mass spectrometry to define the "lipidome" in prostate tumors with matched benign tissues (n = 21), independent unmatched tissues (n = 47), and primary prostate explants cultured with the clinical AR antagonist enzalutamide (n = 43). Significant differences in lipid composition were detected and spatially visualized in tumors compared with matched benign samples. Notably, tumors featured higher proportions of monounsaturated lipids overall and elongated fatty acid chains in phosphatidylinositol and phosphatidylserine lipids. Significant associations between lipid profile and malignancy were validated in unmatched samples, and phospholipid composition was characteristically altered in patient tissues that responded to AR inhibition. Importantly, targeting tumor-related lipid features via inhibition of acetyl-CoA carboxylase 1 significantly reduced cellular proliferation and induced apoptosis in tissue explants. This characterization of the prostate cancer lipidome in clinical tissues reveals enhanced fatty acid synthesis, elongation, and desaturation as tumor-defining features, with potential for therapeutic targeting. SIGNIFICANCE: This study identifies malignancy and treatment-associated changes in lipid composition of clinical prostate cancer tissues, suggesting that mediators of these lipidomic changes could be targeted using existing metabolic agents.

Growth performance, tissue lipid composition and metabolism, health indices, and serum lipid chemistry of broiler chicken in response to dietary flaxseed and chromium

This study investigated growth performance, growth efficiency, lipid composition, lipid metabolism, health indices, and serum lipid chemistry of broiler chicken fed flaxseed meal (FSM) and Cr. Five dietary treatments were formulated – T1 (control), T2 (100 g FSM), T3 (100 g FSM + 0.5 ppm Cr), T4 (100 g FSM + 1.0 ppm Cr), and T5 (100 g FSM + 1.5 ppm Cr). Each treatment was assigned six replicate groups of day-old broiler chicks with eight birds in each. Feeding of 100 g FSM exerted negative effects on the growth performance during starter phase only (0-3 weeks) and overall growth efficiency parameters in broiler chicken, whereas, Cr supplementation reversed these negative effects. 100 g FSM reduced abdominal fat in chicken and Cr supplementation linearly decreased it with minimum at 1.5 ppm Cr. Feeding of 100 g FSM favourably improved the activities of lipid metabolism enzymes which resulted in improved fatty acid profile and health indices of chicken meat. No significant effect of Cr supplementation was observed on lipid metabolism, fatty acid profile, and health indices of chicken meat. 100 g FSM decreased serum total cholesterol, triglyceride, cardiac risk ratio, atherogenic coefficient, and atherogenic index of plasma, whereas, Cr supplementation decreased these parameters linearly with increasing levels. Antioxidant enzyme activities and lipid peroxidation were increased by FSM, whereas, Cr supplementation linearly decreased them with increasing levels; and inverse trend was observed in serum HDL cholesterol levels. This study concludes that feeding of 100 g FSM exert negative effects on growth performance of young chicken (0-3 weeks), favourably alter lipid metabolism which results in improved fatty acid profile and health indices of chicken meat. It improves the serum lipid profile and atherogenic indices in broiler chicken, but negatively affects the oxidative stability of lipids. However, Cr supplementation at 1.5 ppm level in diet successfully overcomes the negative effects of FSM feeding on growth performance and lipid oxidative stability.

Influence of Varying Dietary ω6 to ω3 Fatty Acid Ratios on the Hepatic Transcriptome, and Association with Phenotypic Traits (Growth, Somatic Indices, and Tissue Lipid Composition), in Atlantic Salmon (Salmo salar).

Simple SummaryPlant oils are routinely used in fish feeds as a fish oil replacement. However, these terrestrial alternatives typically contain high levels of ω6 fatty acids (FA) and, thus, high ω6 to ω3 (ω6:ω3) FA ratios, which influence farmed fish and their consumers. The ω6:ω3 ratio is known to affect many biological processes (e.g., inflammation, FA metabolism) and human diseases; however, its impacts on fish physiology and the underlying molecular mechanisms are less well understood. In this study, we used 44 K microarrays to examine which genes and molecular pathways are altered by variation in dietary ω6:ω3 in Atlantic salmon. Our microarray study showed that several genes related to immune response, lipid metabolism, cell proliferation, and translation were differentially expressed between the two extreme ω6:ω3 dietary treatments. We also revealed that the PPARα activation-related transcript helz2 is a potential novel molecular biomarker of tissue variation in ω6:ω3. Further, correlation analyses illustrated the relationships between liver transcript expression and tissue (liver, muscle) lipid composition, and other phenotypic traits in salmon fed low levels of fish oil. This nutrigenomic study enhanced the current understanding of Atlantic salmon gene expression response to varying dietary ω6:ω3.The importance of dietary omega-6 to omega-3 (ω6:ω3) fatty acid (FA) ratios for human health has been extensively examined. However, its impact on fish physiology, and the underlying molecular mechanisms, are less well understood. This study investigated the influence of plant-based diets (12-week exposure) with varying ω6:ω3 (0.4–2.7) on the hepatic transcriptome of Atlantic salmon. Using 44 K microarray analysis, genes involved in immune and inflammatory response (lect2a, itgb5, helz2a, p43), lipid metabolism (helz2a), cell proliferation (htra1b), control of muscle and neuronal development (mef2d) and translation (eif2a, eif4b1, p43) were identified; these were differentially expressed between the two extreme ω6:ω3 dietary treatments (high ω6 vs. high ω3) at week 12. Eight out of 10 microarray-identified transcripts showed an agreement in the direction of expression fold-change between the microarray and qPCR studies. The PPARα activation-related transcript helz2a was confirmed by qPCR to be down-regulated by high ω6 diet compared with high ω3 diet. The transcript expression of two helz2 paralogues was positively correlated with ω3, and negatively with ω6 FA in both liver and muscle, thus indicating their potential as biomarkers of tissue ω6:ω3 variation. Mef2d expression in liver was suppressed in the high ω6 compared to the balanced diet (ω6:ω3 of 2.7 and 0.9, respectively) fed fish, and showed negative correlations with ω6:ω3 in both tissues. The hepatic expression of two lect2 paralogues was negatively correlated with viscerosomatic index, while htra1b correlated negatively with salmon weight gain and condition factor. Finally, p43 and eif2a were positively correlated with liver Σω3, while these transcripts and eif4b2 showed negative correlations with 18:2ω6 in the liver. This suggested that some aspects of protein synthesis were influenced by dietary ω6:ω3. In summary, this nutrigenomic study identified hepatic transcripts responsive to dietary variation in ω6:ω3, and relationships of transcript expression with tissue (liver, muscle) lipid composition and other phenotypic traits.

Characterization of the cardiac phospholipidome of small cetaceans provides adaptational insight and a foundation for indirect population health screening

AbstractThe maintenance of a tightly regulated heart lipidome is a general hallmark of mammal health. However, in the case of cetaceans, heart tissue lipid composition remains obscure. This work represents a first in‐depth state‐of‐the‐art characterization of the lipid content of small cetacean hearts, namely those of Delphinus delphis, Phocoena phocoena, and Stenella coeruleoalba. Phospholipid classes identified were similar to those found in terrestrial mammals. Regarding fatty acid profiles, they revealed a much higher n‐3 fatty acid content than that reported for terrestrial counterparts. Phospholipidome characterization allowed identification of 198 lipid species, including phospholipids, lysophospholipids, and sphingomyelins, generally characterized by a high content of species with esterified n‐3 fatty acids. The cardiac lipid profile of the three cetacean species is similar in terms of lipid classes, fatty acids, and even molecular lipid species present. However, quantitative differences suggest a divergence of S. coeruleoalba from the other species in terms of fatty acid and phospholipid profile. The identified differences regarding terrestrial counterparts will contribute to better understanding the details of small cetacean cardiac physiology. Moreover, the characterization of cardiac phospholipidome may represent an opportunity to establish lipidomic‐based practical tools to reliably and reproducibly assess small cetacean health population status by remote sampling.

Influence of Dietary Long-Chain Polyunsaturated Fatty Acids and ω6 to ω3 Ratios on Head Kidney Lipid Composition and Expression of Fatty Acid and Eicosanoid Metabolism Genes in Atlantic Salmon (Salmo salar).

The interaction of dietary eicosapentaenoic acid and docosahexaenoic acid (EPA+DHA) levels with omega-6 to omega-3 ratios (ω6:ω3), and their impact on head kidney lipid metabolism in farmed fish, are not fully elucidated. We investigated the influence of five plant-based diets (12-week exposure) with varying EPA+DHA levels (0.3, 1.0, or 1.4%) and ω6:ω3 (high ω6, high ω3, or balanced) on tissue lipid composition, and transcript expression of genes involved in fatty acid and eicosanoid metabolism in Atlantic salmon head kidney. Tissue fatty acid composition was reflective of the diet with respect to C18 PUFA and MUFA levels (% of total FA), and ω6:ω3 (0.5–1.5). Fish fed 0.3% EPA+DHA with high ω6 (0.3% EPA+DHA↑ω6) had the highest increase in proportions (1.7–2.3-fold) and in concentrations (1.4-1.8-fold) of arachidonic acid (ARA). EPA showed the greatest decrease in proportion and in concentration (by ~½) in the 0.3% EPA+DHA↑ω6 fed fish compared to the other treatments. However, no differences were observed in EPA proportions among salmon fed the high ω3 (0.3 and 1.0% EPA+DHA) and balanced (1.4% EPA+DHA) diets, and DHA proportions were similar among all treatments. Further, the transcript expression of elovl5a was lowest in the 0.3% EPA+DHA↑ω6 fed fish, and correlated positively with 20:3ω3, 20:4ω3 and EPA:ARA in the head kidney. This indicates that high dietary 18:3ω3 promoted the synthesis of ω3 LC-PUFA. Dietary EPA+DHA levels had a positive impact on elovl5a, fadsd5 and srebp1 expression, and these transcripts positively correlated with tissue ΣMUFA. This supported the hypothesis that LC-PUFA synthesis is positively influenced by tissue MUFA levels in Atlantic salmon. The expression of pparaa was higher in the 0.3% EPA+DHA↑ω6 compared to the 0.3% EPA+DHA↑ω3 fed fish. Finally, significant correlations between head kidney fatty acid composition and the expression of eicosanoid synthesis-related transcripts (i.e., 5loxa, 5loxb, cox1, cox2, ptges2, ptges3, and pgds) illustrated the constitutive relationships among fatty acids and eicosanoid metabolism in salmon.

Extracted microbial oil from a novel Schizochytrium sp. (T18) as a sustainable high DHA source for Atlantic salmon feed: Impacts on growth and tissue lipids

The use of microbial oil, high in docosahexaenoic acid (DHA), was investigated as a lipid source in diets for farmed Atlantic salmon. Schizochytrium sp. oil is produced from heterotrophic fermentation and it can be a renewable source of long-chain n-3 fatty acids due to its high DHA content. A 16-week feeding trial was conducted on Atlantic salmon (24 g initial weight) in freshwater to test the effects of microbial oil (MO) from Schizochytrium sp. (T18), on fish growth performance and tissue lipid and fatty acid composition. Four experimental diets were tested: a reference diet (20% FO) and a commercial-type control diet (10% FO + 10% vegetable oil), a low MO diet (5% MO) and a high MO diet (10% MO). There were no differences in weight gain (81–98 g), condition factor (1.08), specific growth rate (1.30–1.53%/day), nor feed conversion ratio (0.84–0.90) among all treatments (p > 0.05). Fatty acids in total lipid in the muscle reflected the fatty acid profile in the diet, particularly in salmon fed low and high MO diets, with high muscle storage of DHA and low EPA compared to salmon fed the FO and FO/VO control diets. Overall, Schizochytrium sp. (T18) is a candidate for use in dietary oil blends for juvenile salmon.