Lipid Oxidation Research Articles

Unraveling the mechanism of malancao in treating ulcerative colitis: A multi-omics approach

BACKGROUND Malancao (MLC) is a traditional Chinese medicine with a long history of utilization in treating ulcerative colitis (UC). Nevertheless, the precise molecular mechanisms underlying its efficacy remain elusive. This study leveraged ultra-high-performance liquid chromatography coupled with exactive mass spectrometry (UHPLC-QE-MS), network pharmacology, molecular docking (MD), and gene microarray analysis to discern the bioactive constituents and the potential mechanism of action of MLC in UC management. AIM To determine the ingredients related to MLC for treatment of UC using multiple databases to obtain potential targets for fishing. METHODS This research employs UHPLC-QE-MS for the identification of bioactive compounds present in MLC plant samples. Furthermore, the study integrates the identified MLC compound-related targets with publicly available databases to elucidate common drug disease targets. Additionally, the R programming language is utilized to predict the central targets and molecular pathways that MLC may impact in the treatment of UC. Finally, MD are conducted using AutoDock Vina software to assess the affinity of bioactive components to the main targets and confirm their therapeutic potential. RESULTS Firstly, through a comprehensive analysis of UHPLC-QE-MS data and public database resources, we identified 146 drug-disease cross targets related to 11 bioactive components. The Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis highlighted that common disease drug targets are primarily involved in oxidative stress management, lipid metabolism, atherosclerosis, and other processes. They also affect AGE-RAGE and apoptosis signaling pathways. Secondly, by analyzing the differences in diseases, we identified key research targets. These core targets are related to 11 active substances, including active ingredients such as quercetin and luteolin. Finally, MD analysis revealed the stability of compound-protein binding, particularly between JUN-Luteolin, JUN-Quercetin, HSP90AA1-Wogonin, and HSP90AA1-Rhein. Therefore, this suggests that MLC may help alleviate intestinal inflammation in UC, restore abnormal lipid accumulation, and regulate the expression levels of core proteins in the intestine. CONCLUSION The utilization of MLC has demonstrated notable therapeutic efficacy in the management of UC by means of the compound target interaction pathway. The amalgamation of botanical resources, metabolomics, natural products, MD, and gene chip technology presents a propitious methodology for investigating therapeutic targets of herbal medicines and discerning novel bioactive constituents.

MARK4 aggravates cardiac dysfunction in mice with STZ-induced diabetic cardiomyopathy by regulating ACSL4-mediated myocardial lipid metabolism

Diabetic cardiomyopathy is a specific type of cardiomyopathy. In DCM, glucose uptake and utilization are impaired due to insulin deficiency or resistance, and the heart relies more heavily on fatty acid oxidation for energy, resulting in myocardial lipid toxicity-related injury. MARK4 is a member of the AMPK-related kinase family, and improves ischaemic heart failure through microtubule detyrosination. However, the role of MARK4 in cardiac regulation of metabolism is unclear. In this study, after successful establishment of a diabetic cardiomyopathy model induced by streptozotocin and a high-fat diet, MARK4 expression was found to be significantly increased in STZ-induced DCM mice. After AAV9-shMARK4 was administered through the tail vein, decreased expression of MARK4 alleviated diabetic myocardial damage, reduced oxidative stress and apoptosis, and facilitated cardiomyocyte mitochondrial fusion, and promoted myocardial lipid oxidation metabolism. In addition, through the RNA-seq analysis of differentially expressed genes, we found that MARK4 deficiency promoted lipid decomposition and oxidative metabolism by downregulating the expression of ACSL4, thus reducing myocardial lipid accumulation in the STZ-induced DCM model.

Clove essential oil decreases antemortem stress and acts as an antioxidant in Nile tilapia

ABSTRACT This study investigated the effect of clove essential oil used prior to stunning by cranial percussion and hypothermia on Nile tilapia (Oreochromis niloticus) welfare and fillet quality. A total of 100 tilapias were divided into four groups in a 2 × 2 factorial design, exploring two stunning methods with and without clove essential oil. Behavioral responses, glucose, lactate, pH, water holding capacity, color parameters, lipid and protein oxidation, and oxidative stress were analyzed. The application of clove essential oil resulted in 100% numbing in swimming and stimulus response behaviors, and 96% in balance and eye vestibule reflex variables. Significant reductions in glucose (12.12 mg dL−1) for hypothermia group (p = 0.001) and lactate (3.36 mmol L−1) for cranial percussion (p = 0.004), 0.028 nmol lipid oxidation in hypothermia treatment (p = 0.009), and 0.134 nmol carbonyls/mg protein (p = 0.001) were observed. There was a reduction in luminosity (p = 0.010) and red intensity (p = 0.001) in the group of fish fillet that received cranial percussion, however, there was no difference in the group stunned by hypothermia. Clove essential oil demonstrates effectiveness in pre-slaughter stress mitigation, influencing the antioxidant system positively. Its usage in pre-slaughter protocols could contribute to improved fillet quality, presenting a promising alternative for enhancing tilapia welfare during slaughter.

Antioxidant and antimicrobial characteristics of mangosteen peel extract and synergistic capacity in beef burger preservation

SummaryThis study aimed to investigate the efficiency of mangosteen peel extract (MPE) in preservation of beef burgers. MPE was first evaluated for its total phenolic content (TPC), total flavonoid content (TFC) and antioxidant and antimicrobial activities. Subsequently, beef burgers were prepared with different MPE amounts (0–1%) and stored for 1 day, 3 days and 5 days. The synthetic antioxidant 2,6‐di‐tert‐butyl‐4‐methyl phenol (BHT) and synthetic antimicrobial sodium benzoate (SB) were used for comparison. The changes of burgers in physicochemical parameters (moisture, cooking loss, storage loss and pH), lipid and protein oxidation (peroxide value, PV; thiobarbituric acid reactive substances, TBARS and carbonyl content), microbiological (total viable count, TVC) and sensory characteristics were assessed. The results revealed that MPE contained a high TPC of 128.93 mg gallic acid equivalent g−1 dry extract and TFC of 62.98 mg rutin equivalent g−1 dry extract. These bioactive compounds rendered MPE with its antioxidant activity approximately equivalent to ascorbic acid and antimicrobial activities against Escherichia coli and Staphylococcus aureus comparable with SB. MPE‐combined burger samples had higher moisture and cooking loss (P < 0.05) but almost equal storage loss and pH value compared with the control samples (P > 0.05). However, the incorporation of MPE into beef burgers did not affect the sensory attributes and preferences of consumers (P > 0.05). The burger with 1% MPE had lower values of PV, TBARS and carbonyl content than all other samples (P < 0.05), including the one added with BHT, indicating the strong potential of MPE as natural antioxidant alternative to prevent the oxidation of lipids and proteins. Through the TVC test, 1% MPE was demonstrated to result in the safe preservation of burgers up to 5 days of storage, equivalent to SB (P > 0.05). Therefore, MPE could become a natural synergistic alternative to both synthetic antioxidant and antimicrobial in the preservation of meat and meat products.

Effect of Farming System Type on Broilers’ Antioxidant Status, Performance, and Carcass Traits: An Industrial-Scale Production Study

The global demand for improvement in the welfare conditions of broilers has generated the necessity to implement alternative rearing systems as well as less intensive growth hybrids. The majority of the data on alternative farming methods, notwithstanding their abundance, are the result of small-scale experiments. The present extended field study examined the effect of two different industrial farming systems on broilers’ antioxidant status, performance, and meat quality, including 13 replicates of each industrial breeding system (intensive conventional; free range) and two different chicken genotypes (fast growth; slow growth). The duration of the study was 51 months, and the total number of broilers was 260.000 for the conventional and 78.000 for the free-range system. The results showed that fast-growth chicks demonstrated a more satisfactory performance (in terms of body weight gain (BWG) and feed conversion ratio (FCR) with p ≤ 0.001), reduced serum lipid oxidation (p ≤ 0.05), and more tender meat. Contrarily, slow-growth chickens presented significantly higher total antioxidant capacity (TAC) in serum and thigh muscle (p ≤ 0.001), significantly lower (p ≤ 0.05) thigh muscle oxidation (in terms of thiobarbituric acid reactive substances, TBARS), increased protein and decreased fat content (p ≤ 0.05), and better smell, taste, color, and texture. In conclusion, the free-range farming system for slow-growth chickens may result in an overall higher nutritional value, sensory score, and serum and thigh muscle antioxidant profile than the conventional farming system for fast-growth broilers. However, fast-growth broilers exhibit better performance and might undergo less stress.

Use of phytic acid from rice bran combined with sodium erythorbate as antioxidants in chicken mortadella

The antioxidant effect of purified phytic acid (PPA) from rice bran (rice polishing by-product) combined with sodium erythorbate (SE) was evaluated for the first time in mortadella (added with 60% mechanically separated meat), a cured product with high-fat content and highly prone to oxidation, characteristic in Brazil. PPA proved effective compared to standard analytical grade phytic acid (SPA). Two central composite rotational designs (CCRD) (A and B) were employed to investigate the influence of PPA and SE, and SPA and SE, respectively, on mortadella lipid oxidation evaluated by TBARS after 30 days at 30 °C. Due to the high phytic acid's potent antioxidant capacity, the combination of PPA and SE synergistically reduced mortadella lipid oxidation. Furthermore, PPA from rice bran effectively controlled lipid oxidation in mortadella when combined with SE in the range of 5.0 to 9.0 mmol/kg of SPA and 25.0 to 50.0 mmol/kg of SE.

Multi-omics reveals new links between Fructosamine-3-Kinase (FN3K) and core metabolic pathways

Fructosamine-3-kinases (FN3Ks) are a conserved family of repair enzymes that phosphorylate reactive sugars attached to lysine residues in peptides and proteins. Although FN3Ks are present across the Tree of Life and share detectable sequence similarity to eukaryotic protein kinases, the biological processes regulated by these kinases are largely unknown. To address this knowledge gap, we leveraged the FN3K CRISPR Knock-Out (KO) HepG2 cell line alongside an integrative multi-omics study combining transcriptomics, metabolomics, and interactomics to place these enzymes in a pathway context. The integrative analyses revealed the enrichment of pathways related to oxidative stress response, lipid biosynthesis (cholesterol and fatty acids), and carbon and co-factor metabolism. Moreover, enrichment of nicotinamide adenine dinucleotide (NAD) binding proteins and localization of human FN3K (HsFN3K) to mitochondria suggests potential links between FN3K and NAD-mediated energy metabolism and redox balance. We report specific binding of HsFN3K to NAD compounds in a metal and concentration-dependent manner and provide insight into their binding mode using modeling and experimental site-directed mutagenesis. Our studies provide a framework for targeting these understudied kinases in diabetic complications and metabolic disorders where redox balance and NAD-dependent metabolic processes are altered.

Plant acclimation to ionising radiation requires activation of a detoxification pathway against carbonyl-containing lipid oxidation products.

Ionising γ radiation produces reactive oxygen species by water radiolysis, providing an interesting model approach for studying oxidative stress in plants. Three-week old plants of Arabidopsis thaliana were exposed to a low dose rate (25 mGy h-1) of γ radiation for up to 21 days. This treatment had no effect on plant growth and morphology, but it induced chronic oxidation of lipids which was associated with an accumulation of reactive carbonyl species (RCS). However, contrary to lipid peroxidation, lipid RCS accumulation was transient only, being maximal after 1 day of irradiation and decreasing back to the initial level during the subsequent days of continuous irradiation. This indicates the induction of a carbonyl-metabolising process during chronic ionising radiation. Accordingly, the γ-radiation treatment induced the expression of xenobiotic detoxification-related genes (AER, SDR1, SDR3, ALDH4, and ANAC102). The transcriptomic response of some of those genes (AER, SDR1, and ANAC102) was deregulated in the tga256 mutant affected in three TGAII transcription factors, leading to enhanced and/or prolonged accumulation of RCS and to a marked inhibition of plant growth during irradiation compared to the wild type. These results show that Arabidopsis is able to acclimate to chronic oxidative stress and that this phenomenon requires activation of a carbonyl detoxification mechanism controlled by TGAII. This acclimation did not occur when plants were exposed to an acute γ radiation stress (100 Gy) which led to persistent accumulation of RCS and marked inhibition of plant growth. This study shows the role of secondary products of lipid peroxidation in the detrimental effects of reactive oxygen species.

Synergistic antioxidant and antibacterial activities of polyphenol extracts from mangosteen peels in preservation of Pangasius hypophthalmus fish balls

In recent years, natural preservatives have attracted more and more attention in food processing since they can enhance food shelf-life and safety. In this study, the polyphenol extract was obtained from mangosteen peels using enzyme-microwave assisted method, characterized for its antioxidant and antimicrobial activities and subsequently used as a natural additive in fish ball preservation. Results revealed that the mangosteen peel polyphenol powder (MPP) had a high phenolic content of 154 mg gallic acid equivalent/g dry matter, which led to high 2,2-diphenyl-1-picrylhydrazyl free radical scavenging capacity of 95 mg Trolox equivalent/g dry matter. MPP also exhibited effective antimicrobial activity against E. coli and S. aureus, expressed by its large inhibitory zones (11.3 and 12.1 mm, respectively) and small ratios (less than 4) of minimum bactericidal concentration over minimum inhibitory concentration against tested bacteria. The MPP supplementation at the levels of 38 mg/100 g and 53 mg/100 g into fish balls remarkably improved their gel strength, reduced lipid oxidation, limited protein oxidation and structural degradation as compared to those of the control without any addition or with synthetic preservatives. Especially, the addition of 53 mg MPP/100 g could sufficiently retard the microorganism growth. The synergistic effects of MPP in both antioxidant and antimicrobial activities hence could extend the shelf-life of fish balls, more than 40 %, as compared to butylated hydroxytoluene (synthetic antioxidant) or sodium benzoate (synthetic antimicrobial) with their single effects. These findings imply that MPP could be potentially used as a natural additive in preservation of fish and meat products.

Investigation of antioxidant edible coating and modified atmosphere packaging for enhancing storability of hazelnut kernels

This study investigated the effects of antioxidant edible coating and modified atmosphere packaging for improving storability of dried hazelnut kernels by delaying lipid oxidation and color degradation. Hazelnut kernels were coated with different coating matrix (methylcellulose and chitosan) that contain different antioxidant substances (DL-α-tocopherol acetate, cinnamon essential oil, rosemary essential oil and hazelnut oil) and subjected to an accelerated storage condition at 35 °C for 270 days. Hazelnut kernels were also packed under modified atmosphere (MAP) with 100 % N2 in mylar bags and stored at 35 °C for 180 days. Lipid oxidation (free fatty acids, K232 and K270, peroxide values) and color (browning index) were measured for investigating quality changes during the storage. The free fatty acids of kernels from two packaging experiments remained stable during storage. K232 value of MAP kernels was significantly lower (2.20) than that of control (2.90) at the end of the storage, showing delayed production of conjugated dienes. The chitosan based edible coating with encapsulated cinnamon essential oil and oleic acid (CH/ECO/OA) resulted in significantly (P < 0.05) lower PV values (0.53 meq/kg oil), and all the coated samples had the positive effect on reducing browning index with 12–25 compared with control. K270 (0.04–0.18) remained relatively low throughout the long-term storage. As a result, modified atmosphere packaging performed better than edible coatings. This study demonstrated the importance of implicating proper postharvest technology for reducing lipid oxidation and quality deteriorations of hazelnut kernels during prolonged storage.

Effect of radio frequency roasting on the lipid profile of peanut oil and the mechanism of lipids transformation: Revealed by untargeted lipidomics approach

Radio frequency (RF) heating has been proved an alternative roasting method for peanuts, which could effectively degrade aflatoxins and possesses the advantages of greater heating efficiency and penetration depth. This study aimed to investigate the influences of RF roasting on the lipid profile of peanut oil under 150 °C target temperature with varied peanut moisture contents (8.29 % and 20 %) and holding times (0, 7.5, and 15 min), using ultra-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (UPLC-QTOF-MS/MS)-based lipidomics. In total, 2587 lipid species from 35 subclasses were identified. After roasting, the contents of sterol lipid (ST) and subclasses of glycerophospholipids (GPs) and glycoglycerolipids increased significantly, while fatty acid (FA), Oxidized (Ox-) FA, cholesterol (CE), and all subclasses of glycerolipids (GLs) decreased, and 1084 differential lipids were screened. The highest ST and lowest CE contents in peanut oil were achieved by medium roasting (7.5 min). The raise in moisture content of peanut simply affected a few GPs subclasses adversely. Compared with hot air (HA) roasting, RF decelerated lipid oxidation, showing higher levels of diacylglycerol, triacylglycerol and FA, with no additional negative impact and only 69 exclusive differential lipids. During RF roasting, hydrolysis and oxidation of fatty acyl chains into secondary oxides were the central behaviors of lipids transformation. This study could provide insights into the lipid changes and transformation mechanism of peanut oil by RF roasting processing.

M6A RNA Methylation and Implications for Hepatic Lipid Metabolism.

This review presents a summary of recent progress in research on the N6-methyladenosine (m6A) modification and regulatory roles in hepatic lipid metabolism. As the most abundant internal modification of eukaryotic RNA, the m6A modification is a dynamic and reversible process of the m6A enzyme system, which includes writers, erasers, and readers. m6A methylation depressed lipid synthesis and facilitated lipolysis in liver. The depletion of m6A methyltransferase Mettl14/Mettl3 raised fatty acid synthase (FAS), stearoyl-CoA desaturase-1 (SCD1), acetyl-CoA carboxylase (ACC), and elongase of very long chain fatty acids 6 (ELOVL6) in rodent liver, causing increases in liver weight, triglyceride (TG) production, and content in hepatocytes. FTO catalyzed m6A demethylation and the suppression m6A reader YTHDC2 promoted hepatocellular TG generation and hepatic steatosis in C57BL/6 mice through sterol regulatory element-binding protein 1c (SREBP-1c) signaling pathway, which upregulated the lipogenic genes FAS, SCD1, ACC, recombinant acetyl coenzyme a carboxylase alpha, and cell death-inducing DNA fragmentation factor-like effector C (CIDEC). Furthermore, FTO overexpression did not only enhance mitochondrial fusion to impair mitochondrial function and lipid oxidation but also promoted lipid peroxidation, accompanied by excessive TG in hepatocytes and rodent liver. Elevated m6A modification potently suppressed hepatic lipid accumulation, while the shrinkage of m6A modification arose hepatic lipid deposition. These findings have highlighted the beneficial role of m6A RNA methylation in hepatic lipid metabolism, potentially protecting liver from lipid metabolic disorders.

Licochalcone A alleviates ferroptosis in doxorubicin-induced cardiotoxicity via the PI3K/AKT/MDM2/p53 pathway.

Licochalcone A (Lico A), a flavonoid found in licorice, possesses multiple pharmacological activities in modulating oxidative stress, glycemia, inflammation, and lipid metabolism. This study aimed to explore the potential mechanism of Lico A in mitigating ferroptosis associated with doxorubicin-induced cardiotoxicity (DIC). Initially, network pharmacology analysis was applied to identify the active components present in licorice and their targeted genes associated with DIC. Subsequently, to assess the role of Lico A in a DIC mouse model, electrocardiograms, myocardial injury markers, and myocardial histopathological changes were measured. Additionally, cell viability, reactive oxygen species (ROS), ferrous iron, glutathione/glutathione disulfide (GSH/GSSG), and malondialdehyde (MDA) were measured in the cell model as hallmarks of ferroptosis. Finally, the PI3K/AKT/MDM2/p53 signaling pathway and ferroptosis-related proteins were measured in vitro and in vivo. Bioinformatics results revealed that 8 major compounds of licorice, including Lico A, primarily regulated targets such as p53 and the PI3K/AKT signaling pathways in DIC. In the mouse model of DIC, Lico A significantly ameliorated serum biomarkers, histopathology, and electrocardiogram abnormalities. Pretreatment with Lico A enhanced the viability of H9C2 cells treated with doxorubicin. Furthermore, Lico A administration resulted in decreased levels of ROS, ferrous iron, and MDA and increased levels of GSH/GSSG. At the protein level, Lico A increased the phosphorylation of PI3K/AKT/MDM2, reduced p53 accumulation, and induced the upregulation of SLC7A11 and GPX4 expression. However, selective inhibition of PI3K/AKT and plasmid-based overexpression of p53 significantly abolished the anti-ferroptosis functions of Lico A. In conclusion, Lico A attenuates DIC by suppressing p53-mediated ferroptosis through activating PI3K/AKT/MDM2 signaling.

Characterization of the Proximate Composition, Lipid Oxidation Status, and Mineral Content of Mature Tree Nuts from Nine Hazelnut Cultivars Grown in the United States

Characterization of the Proximate Composition, Lipid Oxidation Status, and Mineral Content of Mature Tree Nuts from Nine Hazelnut Cultivars Grown in the United States

Polluted water from a storage dam (Villa Victoria, méxico) induces oxidative damage, AChE activity, embryotoxicity, and behavioral changes in Cyprinus carpio larvae

The Villa Victoria dam is one of the most important storage reservoirs in Mexico since it distributes water to more than 20 million inhabitants in the Metropolitan Zone of Mexico City. In this dam, the common carp (Cyprinus carpio) is an important food resource for the inhabitants, so the aim of this work was to evaluate the oxidative damage (lipoperoxidation, oxidized proteins, antioxidant enzymes activity and gene expression), AChE, embryotoxicity and behavioral changes in C. carpio embryos and larvae exposed to water from Villa Victoria dam for 24, 48, 72 and 96 h. The embryotoxicity was evaluated trough the General Morphology Score (GMS) and the teratogenic index. Behavioral changes in basal locomotor activity and thigmotaxis were evaluated in a DanioVision, Noldus ™. An increase in lipid and protein oxidation as well as modification of CAT, SOD and GPx enzymatic activity was observed during the exposure times. The GMS indicated a low development in the embryos, the teratogenic index was less than 1, however teratogenic effects as yolk edema, fin malformation, head malformation and scoliosis were observed. In parallel, an increase in AChE activity and gene expression was observed reflecting changes in distance traveled of the basal locomotor activity and thigmotaxis at the sampling points. In conclusion, pollutants in water from Villa Victoria dam caused oxidative damage, changes in SOD, CAT, GPx and AChE activity as well as embryotoxicity and modifications in the behavior of C. carpio larvae. This study demonstrates the need to implement restoration programs for this reservoir since, contamination in the Villa Victoria dam could eventually endanger aquatic life and human health.

Low GPR81 in ER+ breast cancer cells drives tamoxifen resistance through inducing PPARα-mediated fatty acid oxidation

AimsThe intricate molecular mechanisms underlying estrogen receptor-positive (ER+) breast carcinogenesis and resistance to endocrine therapy remain elusive. In this study, we elucidate the pivotal role of GPR81, a G protein-coupled receptor, in ER+ breast cancer (BC) by demonstrating low expression of GPR81 in tamoxifen (TAM)-resistant ER+ BC cell lines and tumor samples, along with the underlying molecular mechanisms. Main methodsFatty acid oxidation (FAO) levels and lipid accumulation were explored using MDA and FAβO assay, BODIPY 493/503 staining, and Lipid TOX staining. Autophagy levels were assayed using CYTO-ID detection and Western blotting. The impact of GPR81 on TAM resistance in BC was investigated through CCK8 assay, colony formation assay and a xenograft mice model. ResultsAberrantly low GPR81 expression in TAM-resistant BC cells disrupts the Rap1 pathway, leading to the upregulation of PPARα and CPT1. This elevation in PPARα/CPT1 enhances FAO, impedes lipid accumulation and lipid droplet (LD) formation, and subsequently inhibits cell autophagy, ultimately promoting TAM-resistant BC cell growth. Moreover, targeting GPR81 and FAO emerges as a promising therapeutic strategy, as the GPR81 agonist and the CPT1 inhibitor etomoxir effectively inhibit ER+ BC cell and tumor growth in vivo, re-sensitizing TAM-resistant ER+ cells to TAM treatment. ConclusionOur data highlight the critical and functionally significant role of GPR81 in promoting ER+ breast tumorigenesis and resistance to endocrine therapy. GPR81 and FAO levels show potential as diagnostic biomarkers and therapeutic targets in clinical settings for TAM-resistant ER+ BC.

Molecular Mechanism of the Impact of Lipid Oxidation Products (2,4-Decadienal) on the Conformation of Grouper (Epinephelus coioides) Myofibrillar Proteins During Refrigeration and its Implications on the Overall Protein Flavor

Molecular Mechanism of the Impact of Lipid Oxidation Products (2,4-Decadienal) on the Conformation of Grouper (Epinephelus coioides) Myofibrillar Proteins During Refrigeration and its Implications on the Overall Protein Flavor

Adverse effects of excessive dietary arachidonic acid on survival, PUFA-derived enzymatic and non-enzymatic oxylipins, stress response in rainbow trout fry

Arachidonic acid (C20: 4n-6, AA) plays a fundamental role in fish physiology, influencing growth, survival and stress resistance. However, imbalances in dietary AA can have detrimental effects on fish health and performance. Optimal AA requirements for rainbow trout have not been established. This study aimed to elucidate the effects of varying dietary AA levels on survival, growth, long-chain polyunsaturated fatty acid (LC-PUFA) biosynthetic capacity, oxylipin profiles, lipid peroxidation, and stress resistance of rainbow trout fry. Over a period of eight weeks, 4000 female rainbow trout fry at the resorptive stage (0.12 g) from their first feeding were fed diets with varying levels of AA (0.6%, 1.1% or 2.5% of total fatty acids) while survival and growth metrics were closely monitored. The dietary trial was followed by an acute confinement stress test. Notably, while the fatty acid profiles of the fish reflected dietary intake, those fed an AA-0.6% diet showed increased expression of elongase5, highlighting their inherent ability to produce LC-PUFAs from C18 PUFAs and suggesting potential AA or docosapentaenoic acidn-6 (DPAn-6) biosynthesis. However, even with this biosynthetic capacity, the trout fed reduced dietary AA had higher mortality rates. The diet had no effect on final weight (3.38 g on average for the three diets). Conversely, increased dietary AA enhanced eicosanoid production from AA, suggesting potential inflammatory and oxidative consequences. This was further evidenced by an increase in non-enzymatic lipid oxidation metabolites, particularly in the AA-2.5% diet group, which had higher levels of phytoprostanes and isoprostanes, markers of cellular oxidative damage. Importantly, the AA-1.1% diet proved to be particularly beneficial for stress resilience. This was evidenced by higher post-stress turnover rates of serotonin and dopamine, neurotransmitters central to the fish's stress response. In conclusion, a dietary AA intake of 1.1% of total fatty acids appears to promote overall resilience in rainbow trout fry.

Revealing the evolution of lipid extracts from tilapia (Oreochromis mossambicus) during cold storage: Based on lipid metabolism analysis via GC-Q-MS and characterization of lipid oxidation

Lipid oxidation of tilapia is unavoidable during cold storage. Therefore, this study revealed the lipid metabolism process of tilapia using gas chromatography-quadrupole-mass spectrometry (GC-Q-MS) based lipid metabolism analysis, analyzed the free radicals, and characterized the lipid oxidation and free fatty acids (FFAs) to clarify the contribution of lipid in tilapia during cold storage. Three important metabolic pathways including biosynthesis of unsaturated fatty acids, fatty acids degradation, and fatty acids biosynthesis and differential metabolites were screened. A metabolic network map related to lipid metabolism was constructed. And from the indicators characterizing the lipid oxidation, free radicals, and the FAAs profiles displayed that the lipid was oxidized to a higher degree during cold storage. Overall, this study provided an explanation of lipid oxidation and the contribution of lipid metabolism in tilapia during cold storage, which helps in the insights on the improvement and regulation of quality.

Novel Insights into Psychosis and Antipsychotic Interventions: From Managing Symptoms to Improving Outcomes.

For the past 70 years, the dopamine hypothesis has been the key working model in schizophrenia. This has contributed to the development of numerous inhibitors of dopaminergic signaling and antipsychotic drugs, which led to rapid symptom resolution but only marginal outcome improvement. Over the past decades, there has been limited research on the quantifiable pathological changes in schizophrenia, including premature cellular/neuronal senescence, brain volume loss, the attenuation of gamma oscillations in electroencephalograms, and the oxidation of lipids in the plasma and mitochondrial membranes. We surmise that the aberrant activation of the aryl hydrocarbon receptor by toxins derived from gut microbes or the environment drives premature cellular and neuronal senescence, a hallmark of schizophrenia. Early brain aging promotes secondary changes, including the impairment and loss of mitochondria, gray matter depletion, decreased gamma oscillations, and a compensatory metabolic shift to lactate and lactylation. The aim of this narrative review is twofold: (1) to summarize what is known about premature cellular/neuronal senescence in schizophrenia or schizophrenia-like disorders, and (2) to discuss novel strategies for improving long-term outcomes in severe mental illness with natural senotherapeutics, membrane lipid replacement, mitochondrial transplantation, microbial phenazines, novel antioxidant phenothiazines, inhibitors of glycogen synthase kinase-3 beta, and aryl hydrocarbon receptor antagonists.