N-3 PUFA improved post-menopausal depression induced by maternal separation and chronic mild stress through serotonergic pathway in rats-effect associated with lipid mediators

Effects of Omega-3 PUFAs on lipid profiles and antioxidant response in depressed adolescents: A metabolomic and lipidomic study

Adolescent depression is a significant global health challenge, with many patients responding inadequately to antidepressant treatments. Omega-3 polyunsaturated fatty acids (ω3 PUFAs) have been proposed as a potential adjunctive treatment, but their precise mechanisms remain poorly understood. This study aimed to explore the mechanisms through which ω3 PUFAs exert their antidepressant effects and to identify potential biomarkers for their therapeutic response. A comprehensive assessment of plasma metabolomic and erythrocyte membrane lipidomic was performed on 51 depressed adolescents who were randomly assigned to received either ω3 PUFAs plus paroxetine (n = 27) or paroxetine alone (n = 24) for 12 weeks. Following ω3 PUFA supplementation, phospholipid metabolism emerged as the most significantly altered pathway. ω3 PUFAs markedly influenced the composition of membrane fatty acids, significantly increasing the ω3 PUFA content, decreasing the ω6/ω3 PUFA ratio, and increasing membrane fluidity. Notably, ω3 PUFAs reduced lipid peroxidation in both plasma and cell membranes while enhancing antioxidant capacity in the membranes. Moreover, alterations in phospholipids and membrane function were significantly correlated with improvements in depressive symptoms and cognitive function. Importantly, ω3 PUFA supplementation resulted in greater improvement in clinical symptoms compared to the non-supplemented group exclusively in the subgroup with high baseline oxidative damage levels. This study suggests that ω3 PUFAs promoted phospholipid integration and alleviated oxidative stress, which may account for their antidepressant effects. Lipid oxidation biomarkers could help identify patients likely to benefit from ω3 PUFA supplementation. These findings advance our understanding of the mechanism and clinical application of ω3 PUFAs in treating adolescent depression.

Avocado (Persea americana Mill.) consumption during pregnancy and lactation induces anxiogenic-like behavior, cerebral oxidative stress and compromises fecal microbiota in rat offspring

This study aimed to evaluate the impact of consumption of avocado oil (AO) and pulp (AP) on anxiety-like behavior, cerebral oxidative stress and alteration of the fecal microbiota in the mother and male Wistar rats offspring treated during gestation and lactation. Anxiety-like behavior was measured through the elevated plus maze (EPM) and open field test (OFT) tests. Cerebral malondialdehyde (MDA) and glutathione (GLUT) levels were measured in mothers and offspring. The fatty acid profile was determined for maternal milk and brain. Data showed a shorter time spent on the open arms of EPM in mothers and offspring for those fed AO and AP (P < 0.001). Moreover, the AO offspring adolescent and adult spent less time in the central area (P < 0.05). Furthermore, offspring adults from the AO moved about less and offspring from the AP ambulated more (P < 0.001). MDA was increased in mothers and decreased in the offspring in AO and AP and GLUT was lower in mothers and higher in adolescent and adult offspring in AP (P < 0.05). Polyunsaturated fatty acids in the brain and breast milk in AO and AP were decreased (P < 0.05). Furthermore, there was an increase in the abundance of intestinal bacteria related to the production of inflammatory metabolites that compromised brain function in offspring treated with avocado. These results suggest that avocado induces anxiogenic-like behavior and increases cerebral oxidative stress in mothers and offspring of rats treated during pregnancy and lactation, negatively altering the fecal microbiota of the offspring. So, we report for the first time how the consumption of avocado oil and pulp interferes with a developing organism when consumed in the early stages of life in rats.

The effect of Psilocybe cubensis alkaloids on depressive-like behavior in mice exposed to maternal separation with respect to hippocampal gene expression and DNA methylation of Slc6a4 and Nr3c1

Maternal separation as an early life stress can lead to long-lasting deleterious effects on cognitive and behavioral functions, and the mood state. On the other hand, Psilocybe cubensis (as one of the most well-known magic mushrooms) may be beneficial in the improvement or the treatment of neuropsychiatric disorders. In the present study, we aimed to investigate the effect of P. cubensis extract (PCE) on depressive-like and anxiety-like behaviors, and locomotor activity in mice exposed to early maternal separation. Also, we assessed the expression and methylation level of Slc6a4 and Nr3c1 in the hippocampus. Maternal separation was done in postnatal days (PNDs) 2-18. PCE was intraperitoneally injected at the dose of 20 mg/kg at PND 60, and our tests were done at days 1, 3, and 10, of administration. The results showed that maternal separation significantly induced depressive-like behavior in the forced swim test and anxiety-like behavior in the open field test (OFT). Also, maternal separation decreased locomotor activity in the OFT. In addition, maternal separation decreased the expression and increased the methylation level of both Slc6a4 and Nr3c1 in the hippocampus. However, PCE significantly reversed all these effects. In conclusion, it seems that P. cubensis affects serotonergic signaling via altering Slc6a4 expression and methylation level in the hippocampus of mice. The effect of P. cubensis on Nr3c1 expression and methylation level may also lead to alter the function of the hypothalamus-pituitary-adrenal axis and the stress response in mice exposed to maternal separation.

Environmental enrichment attenuates maternal separation-induced excessive hoarding behavior in adult female mice

BACKGROUND

Previous studies have demonstrated that early life stress (ELS) impacts hoarding behavior in adult humans. This study aimed to assess the potential mitigation by environmental enrichment on hoarding behavior in rodents caused by maternal separation, thereby providing insights into therapeutic strategies for hoarding disorder.

METHODS

Newborn mice were randomly divided into four groups. The control group was allowed to grow naturally. The maternal separation group underwent two weeks of maternal separation. The short-term environmental enrichment group received two weeks of environmental enrichment intervention after the two weeks of maternal separation. The long-term environmental enrichment group received five weeks of environmental enrichment intervention after the two weeks of maternal separation. Hoarding behavior was assessed during adolescence and adulthood. Hippocampal tissue from adult female mice was analyzed using LC-MS/MS-based metabolomics. Spearman correlation analysis was then performed to assess the relationship between differentially expressed metabolites and hoarding behavior.

RESULTS

Environmental enrichment attenuates maternal separation-induced excessive hoarding behavior in adult female mice. The untargeted metabolomics of the hippocampal region in female mice showed that long-term environmental enrichment reversed multiple differential metabolites, including Substance P, which were mainly concentrated in metabolic pathways such as cancer choline metabolism, glycolipid metabolism, and linoleic acid metabolism.

CONCLUSIONS

Our findings indicate that ELS and long-term environmental enrichment have sex-dependent effects on adult hoarding behavior, potentially related to altered hippocampal metabolism. This study highlights the importance of environmental enrichment in mitigating the long-term effects of early maternal separation on hoarding behavior.

The Potential Role of Polyphenol Supplementation in Preventing and Managing Depression: A Review of Current Research

Depression is a common mental illness that affects 5% of the adult population globally. The most common symptoms of depression are low mood, lack of pleasure from different activities, poor concentration, and reduced energy levels for an extended period, and it affects the emotions, behaviors, and overall well-being of an individual. The complex pathophysiology of depression presents challenges for current therapeutic options involving a biopsychosocial treatment plan. These treatments may have a delayed onset, low remission and response rates, and undesirable side effects. Researchers in nutrition and food science are increasingly addressing depression, which is a significant public health concern due to the association of depression with the increased incidence of cardiovascular diseases and premature mortality. Polyphenols present in our diet may significantly impact the prevention and treatment of depression. The primary mechanisms include reducing inflammation and oxidative stress, regulating monoamine neurotransmitter levels, and modulating the microbiota-gut-brain axis and hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis. This review summarizes recent advances in understanding the effects of dietary polyphenols on depression and explores the underlying mechanisms of these effects for the benefit of human health. It also highlights studies that are looking at clinical trials to help future researchers incorporate these substances into functional diets, nutritional supplements, or adjunctive therapy to prevent and treat depression.

Synergistic Antidepressant-like Effects of Biotics and n-3 Polyunsaturated Fatty Acids on Dopaminergic Pathway through the Brain-Gut Axis in Rats Exposed to Chronic Mild Stress

Probiotics, postbiotics, and n-3 polyunsaturated fatty acids (PUFA) have antidepressant-like effects. However, the underlying mechanisms of the dopaminergic pathway are unclear. The present study investigated the hypothesis that probiotics and postbiotics combined with n-3 PUFA synergistically improve depression by modulating the dopaminergic pathway through the brain-gut axis. Rats were randomly divided into seven groups: non-chronic mild stress (CMS) with n-6 PUFA, and CMS with n-6 PUFA, n-3 PUFA, probiotics, postbiotics, probiotics combined with n-3 PUFA, and postbiotics combined with n-3 PUFA. Probiotics, postbiotics, and n-3 PUFA improved depressive behaviors, decreased blood concentrations of interferon-γ, and interleukin-1β, and increased the brain and gut concentrations of short chain fatty acids and dopamine. Moreover, probiotics, postbiotics, and n-3 PUFA increased the brain and gut expression of glucocorticoid receptor and tyrosine hydroxylase; brain expression of l-type amino acid transporter 1 and dopamine receptor (DR) D1; and gut expression of DRD2. The expression of phosphorylated protein kinase A/protein kinase A and phosphorylated cAMP response element-binding protein/cAMP response element-binding protein increased in the brain, however, decreased in the gut by the supplementation of probiotics, postbiotics, and n-3 PUFA. There was synergistic effect of probiotics and postbiotics combined with n-3 PUFA on the depressive behaviors and dopaminergic pathway in blood, brain, and gut. Moreover, no significant difference in the dopaminergic pathways between the probiotics and postbiotics was observed. In conclusion, probiotics and postbiotics, combined with n-3 PUFA have synergistic antidepressant-like effects on the dopaminergic pathway through the brain-gut axis in rats exposed to CMS.

Estrogen-immuno-neuromodulation disorders in menopausal depression

A significant decrease in estrogen levels puts menopausal women at high risk for major depression, which remains difficult to cure despite its relatively clear etiology. With the discovery of abnormally elevated inflammation in menopausal depressed women, immune imbalance has become a novel focus in the study of menopausal depression. In this paper, we examined the characteristics and possible mechanisms of immune imbalance caused by decreased estrogen levels during menopause and found that estrogen deficiency disrupted immune homeostasis, especially the levels of inflammatory cytokines through the ERα/ERβ/GPER-associated NLRP3/NF-κB signaling pathways. We also analyzed the destruction of the blood-brain barrier, dysfunction of neurotransmitters, blockade of BDNF synthesis, and attenuation of neuroplasticity caused by inflammatory cytokine activity, and investigated estrogen-immuno-neuromodulation disorders in menopausal depression. Current research suggests that drugs targeting inflammatory cytokines and NLRP3/NF-κB signaling molecules are promising for restoring homeostasis of the estrogen-immuno-neuromodulation system and may play a positive role in the intervention and treatment of menopausal depression.

Alpha-glycosyl isoquercitrin alleviates subchronic social defeat stress-induced depression symptoms by modulating the microbiota-gut-brain axis in mice

AIMS

Increasing evidence suggests a link between gut microbial dysbiosis and the pathogenesis of depression. Alpha-glycosyl isoquercitrin (AGIQ), consisting of isoquercitrin and its glycosylated quercetin, has beneficial effects on the gut microbiome and brain function. Here, we detected the potential antidepressant impact of a four-week administration of AGIQ and its underlying mechanisms using a mouse model of depression.

MAIN METHODS

Male C57BL/6 mice were orally administered AGIQ (0.05 % or 0.5 % in drinking water) for 28 days; subchronic social defeat stress was performed in the last 10 days. Behavior tests were conducted to assess anxiety and depressive-like behaviors. Additionally, evaluations encompassed 5-hydroxytryptamine (5-HT) levels, the gut microbiota composition, lipopolysaccharide (LPS) concentrations, short-chain fatty acids levels, and intestinal barrier integrity changes.

KEY FINDINGS

AGIQ significantly alleviated depression-like behaviors and increased hippocampal 5-HT levels. Further, AGIQ mitigated stress-induced gut microbial abnormalities and reduced the levels of LPS in the serum, which affected the relative gene expression levels of 5-HT biosynthesis enzymes in vitro. Furthermore, AGIQ reversed the reduced butyrate levels in cecal contents and improved the impaired intestinal barrier by increasing the expression of colonic zonula occluden-1 (ZO-1) and occludin, thereby decreasing LPS leakage.

SIGNIFICANCE

Our results suggest that AGIQ could improve stress-induced depression by regulating the gut microbiome, which inhibits LPS production and maintains the gut barrier. This is the first report on the potential effect of AGIQ on depression via the gut microbiota-brain axis, shedding new light on treatment options.

Synergistic antidepressant-like effect of n-3 polyunsaturated fatty acids and probiotics through the brain-gut axis in rats exposed to chronic mild stress

N-3 polyunsaturated fatty acids (PUFA) and probiotics have antidepressant-like effects, but the underlying mechanisms are unclear. We hypothesized that n-3 PUFA combined with live and dead probiotics synergistically improves depression by modulating the hypothalamic-pituitary-adrenal (HPA) axis and serotonergic pathways through the brain-gut axis. Rats were randomly divided into seven groups (n = 8/group): non-chronic mild stress (CMS) with n-6 PUFA, CMS with n-3 PUFA, n-6 PUFA, live probiotics, dead probiotics, n-3 PUFA and live probiotics, and n-3 PUFA and dead probiotics. Diets of n-6 and n-3 PUFA and oral supplementation of live and dead probiotics were provided for 12 weeks, and CMS was performed for the last 5 weeks. N-3 PUFA and probiotics improved depressive behaviors and modulated the brain and gut HPA axis by synergistically increasing glucocorticoid receptor expression and decreasing corticotropin-releasing factor expression and blood levels of adrenocorticotropic hormone and corticosterone. N-3 PUFA and probiotics upregulated the brain serotonergic pathway through serotonin levels and expression of brain-derived neurotrophic factor, phosphorylated cAMP response binding protein, and 5-hydroxytryptamine 1A receptor while downregulating the gut serotonergic pathway. Furthermore, n-3 PUFA and probiotics increased the abundance of Ruminococcaceae, brain and gut short chain fatty acid levels, and occludin expression while decreasing the expression of tumor necrosis factor-α, interleukin-1β, and prostaglandin E₂ and blood lipopolysaccharides levels. There was no significant difference between the live and dead probiotics. In conclusion, n-3 PUFA and probiotics had synergistic antidepressant-like effects on the HPA axis and serotonergic pathways of the brain and gut through the brain-gut axis.

Long-lasting and sex-dependent effects of late lactational maternal deprivation on socioemotional behaviors in adult mice

The lactation period is an important period for individual development and a sensitive period for the behavioral phenotypes and plasticity of individual offspring. Early life experiences (e.g., maternal deprivation (MD) and neglect) have significant long-lasting and dual effects on individual stress reactivities during adulthood. Theoretically, stress inoculation can improve the adaptive capacity of the body, but overstress can lead to dysfunction when adaptive mechanisms fail.To date, the potential effects of late lactational MD on the socioemotional behaviors of mouse offspring during adulthood are still not fully understood. In the present study, mice were subjected to early deprivation by individually separating pups from their dam for 0 min, 15 min, and 3 h per day from PND 13-25. The social dominance test (SDT), social interaction test (SI), open field test (OFT), and forced swim test (FST) were carried out during adulthood. The results showed that the social dominance of male mice in the 15 min/d MD group significantly increased, especially in low-rank mice. In the 3 h/d MD group, the social dominance of female mice was decreased, especially in the lower-rank mice. The anxiolytic and antidepressant-like effects of the 15 min/d MD group were significantly increased in male mice. Our study provides direct evidence that MD during late lactation period results in long-lasting effects on social dominance as well as on anxiety and depression phenotypes in a sex-dependent manner.

Effect of Family Integrated Care on maternal stress in preterm infants in the Neonatal Intensive Care Unit: A bi-center experience

AIM

To compare the effect of family integrated care (FICare) on maternal stress in preterm infants with traditional non-parent neonatal intensive care unit (NICU) care.

METHODS

We continuously enrolled mothers and their preterm infants from two NICUs between August 2014 and April 2017; while one NICU applied the FICare model (FICare group) and the other performed standard non-parent care model (control group). Maternal stress was evaluated by the Parental Stress Scale: NICU (PSS: NICU) on admission and right before the discharge. A generalized linear model to adjust for potential confounders. Subgroup analysis was also performed for comparisons between two groups.

RESULTS

A total of 215 mothers with preterm infants were included in this study, among whom 118 (54.88%) were in FICare group and 97 (45.12%) were in control group. The mean PSS: NICU score was 117.36 ± 26.27 on admission with no difference between two groups. Before being discharged home, the PSS: NICU score of parents in both groups was significantly reduced, with the score of FICare group was significantly lower than that of control group. In all sub-domains of PSS: NICU score as sights and sounds, baby looks and behavior score, and parental role, the scores of FICare group were significantly lower than control group.

CONCLUSIONS

There was a simultaneous decrease of maternal stress for NICU preterm infants. FICare further facilitates reducing the maternal stress. It shall be encouraged to apply FICare model in NICUs.

Possible Effects and Mechanisms of Dietary Natural Products and Nutrients on Depression and Anxiety: A Narrative Review

Depression and anxiety are severe public health problems and have attracted more and more attention from researchers of food science and nutrition. Dietary natural products and nutrients, such as fish, coffee, tea, n-3 PUFA, lycopene, and dietary fiber, could play a vital role in the prevention and management of these diseases. The potential mechanisms of action mainly include inhibiting inflammation, ameliorating oxidative stress, modulating the microbiota-gut-brain axis, suppressing hypothalamic-pituitary-adrenal axis hyperactivity, and regulating the levels of monoamine neurotransmitters. In this narrative review, we summarize the most recent advancements regarding the effects of dietary natural products and nutrients on depression and anxiety, and their underlying mechanisms are discussed. We hope that this paper can provide a better understanding of the anti-depressive and anxiolytic action of dietary natural products, and that it is also helpful for developing dietary natural products for functional food, dietary supplements, or auxiliary agents for the prevention and management of these diseases.

Sirtuin 3 Plays a Critical Role in the Antidepressant- and Anxiolytic-like Effects of Kaempferol

An estimated 20% of women experience depression at some point during menopause. Hormone replacement therapy (HRT), as the main therapy for depression and other menopausal syndromes, comes with a few undesirable side effects and a potential increase in cancer and cardiovascular risk. Consequently, there is a dire need for the development of new therapies to treat menopausal depression. Oxidative stress combined with the decline in sex hormones might explain the occurrence of psychological symptoms characteristic of menopause. Therefore, antioxidants have been suggested as a promising therapy for aging-associated diseases, such as menopausal depression. As a flavonoid antioxidant, kaempferol might have a potential neuroprotective action. Hence, the study was conducted to assess the potential antidepressant action of kaempferol and clarify the underlying mechanism. The results show that kaempferol has potential beneficial effects on VCD-induced rodent model of menopausal depression and produces antioxidant effects as well as increases the deacetylation of superoxide dismutase 2 (SOD2) and the protein level of Sirtuin3 (Sirt3) in the hippocampus. On the contrary, Sirt3 depletion abrogated the antidepressant- and anxiolytic-like effects as well as antioxidant effects of kaempferol. In conclusion, kaempferol might produce antidepressant effects via upregulating the expression of Sirt3, the major deacetylase in mitochondria, and subsequently activate the mitochondrial antioxidases. These findings shed some light on the use of kaempferol or vegetables and herbs that contain kaempferol as a complementary therapy for menopausal depression.

Possible antidepressant mechanisms of omega-3 polyunsaturated fatty acids acting on the central nervous system

Omega-3 polyunsaturated fatty acids (PUFAs) can play important roles in maintaining mental health and resistance to stress, and omega-3 PUFAs supplementation can display beneficial effects on both the prevention and treatment of depressive disorders. Although the underlying mechanisms are still unclear, accumulated evidence indicates that omega-3 PUFAs can exhibit pleiotropic effects on the neural structure and function. Thus, they play fundamental roles in brain activities involved in the mood regulation. Since depressive symptoms have been assumed to be of central origin, this review aims to summarize the recently published studies to identify the potential neurobiological mechanisms underlying the anti-depressant effects of omega-3 PUFAs. These include that of (1) anti-neuroinflammatory; (2) hypothalamus-pituitary-adrenal (HPA) axis; (3) anti-oxidative stress; (4) anti-neurodegeneration; (5) neuroplasticity and synaptic plasticity; and (6) modulation of neurotransmitter systems. Despite many lines of evidence have hinted that these mechanisms may co-exist and work in concert to produce anti-depressive effects, the potentially multiple sites of action of omega-3 PUFAs need to be fully established. We also discussed the limitations of current studies and suggest future directions for preclinical and translational research in this field.

Epigenetic Mechanism of Early Life Stress-Induced Depression: Focus on the Neurotransmitter Systems

Depression has an alarmingly high prevalence worldwide. A growing body of evidence indicates that environmental factors significantly affect the neural development and function of the central nervous system and then induce psychiatric disorders. Early life stress (ELS) affects brain development and has been identified as a major cause of depression. It could promote susceptibility to stress in adulthood. Recent studies have found that ELS induces epigenetic changes that subsequently affect transcriptional rates of differentially expressed genes. The epigenetic modifications involved in ELS include histone modifications, DNA methylation, and non-coding RNA. Understanding of these genetic modifications may identify mechanisms that may lead to new interventions for the treatment of depression. Many reports indicate that different types of ELS induce epigenetic modifications of genes involved in the neurotransmitter systems, such as the dopaminergic system, the serotonergic system, the gamma-aminobutyric acid (GABA)-ergic system, and the glutamatergic system, which further regulate gene expression and ultimately induce depression-like behaviors. In this article, we review the effects of epigenetic modifications on the neurotransmitter systems in depression-like outcomes produced by different types of ELS in recent years, aiming to provide new therapeutic targets for patients who suffer from depression.

N-3 PUFA ameliorated bone loss induced by postmenopausal depression following exposure to chronic mild stress and maternal separation by regulating neuronal processes

Depression induced by chronic mild stress (CMS) reduced bone mass in ovariectomized (OVX) rats, and maternal separation (MS) during early life aggravated depression-induced bone mass destruction. N-3 polyunsaturated fatty acids (PUFA) have been shown to improve bone mass and depression, but the bone-protecting effects of n-3 PUFA were unclear in CMS+MS-induced depression models. The purpose of this study was to determine whether n-3 PUFA improved CMS+MS-induced postmenopausal bone loss via its antidepressant-like action. Rats were fed diets containing 0% of total energy intake (en %) of n-3 PUFA during lifetime or 1 en % n-3 PUFA during pre-weaning or post-weaning periods, or their entire lifetimes and were allocated to CMS or CMS+MS groups after OVX. Lifetime supply of n-3 PUFA enhanced bone mass and microarchitecture, and expression of runt-related transcription factor 2, while decreasing blood levels of amino-terminal cross-linked telopeptide of type 1 collagen and the expression of receptor activator of nuclear factor kappa Β ligand/osteoprotegerin, activating transcription factor 4, and adrenergic receptor β2. Lifetime supply of n-3 PUFA decreased levels of adrenocorticotropic hormone and corticosterone and the expression of corticotropin-releasing factor in the brain but increased expression of the glucocorticoid receptor, serotonin-2C receptor, cAMP response element-binding protein (CREB), and calmodulin kinase IV and serotonin levels. Supply of n-3 PUFA during the pre-and post-weaning periods had beneficial effects on the brain but not on the bones. Lifetime supply of n-3 PUFA ameliorated bone loss induced by chronic stress by regulating hypothalamic-pituitary-adrenal axis activity and serotonin-CREB signaling.

Oxylipin Responses to Fasting and Insulin Infusion in a Large Mammalian Model of Fasting-Induced Insulin Resistance, the Northern Elephant Seal

The prolonged, post-weaning fast of northern elephant seal (Mirounga angustirostris) pups is characterized by a reliance on lipid metabolism and reversible, fasting-induced insulin resistance providing a unique model to examine the effects of insulin on lipid metabolism. We have previously shown that acute insulin infusion induced a shift in fatty acid metabolism dependent on fasting duration. This study complements the previous study by examining the effects of fasting duration and insulin infusion on circulating levels of oxylipins, bioactive metabolites derived from the oxygenation of polyunsaturated fatty acids. Northern elephant seal pups were studied at two post-weaning periods (n = 5/period): early fasting (1-2 weeks post-weaning; 127 ± 1 kg) and late fasting (6-7 weeks post-weaning; 93 ± 4 kg). Different cohorts of pups were weighed, sedated, and infused with 65 mU/kg of insulin. Plasma was collected prior to infusion (T0), and at 10, 30, 60, and 120 min post-infusion. A profile of ~80 oxylipins were analyzed by UPLC-ESI-MS/MS. Nine oxylipins changed between early and late fasting and eight were altered in response to insulin infusion. Fasting decreased PGF2a and increased 14,15-DiHETrE, 20-HETE, and 4-HDoHE (p<0.03) in T0 samples, while insulin infusion resulted in an inverse change in area under the curve (AUC) levels in these same metabolites (p<0.05). In addition, 12-HpETE and 12-HETE decreased with fasting and insulin infusion, respectively (p<0.04). The oxylipins altered during fasting and in response to insulin infusion may contribute to the manifestation of insulin resistance and participate in the metabolic regulation of associated cellular processes.