Chronic dietary changes in n-6/n-3 polyunsaturated fatty acid ratios cause developmental delay and reduce social interest in mice

What risk factors for Developmental Language Disorder can tell us about the neurobiological mechanisms of language development

Language is a complex multidimensional cognitive system that is connected to many neurocognitive capacities. The development of language is therefore strongly intertwined with the development of these capacities and their neurobiological substrates. Consequently, language problems, for example those of children with Developmental Language Disorder (DLD), are explained by a variety of etiological pathways and each of these pathways will be associated with specific risk factors. In this review, we attempt to link previously described factors that may interfere with language development to putative underlying neurobiological mechanisms of language development, hoping to uncover openings for future therapeutical approaches or interventions that can help children to optimally develop their language skills.

Mice prenatally exposed to valproic acid do not show autism-related disorders when fed with polyunsaturated fatty acid-enriched diets

Dietary supplementations with n-3 polyunsaturated fatty acid (PUFA) have been explored in autism spectrum disorder (ASD) but their efficiency and potential in ameliorating cardinal symptoms of the disease remain elusive. Here, we compared a n-3 long-chain (LC) PUFA dietary supplementation (n-3 supp) obtained from fatty fish with a n-3 PUFA precursor diet (n-3 bal) obtained from plant oils in the valproic acid (VPA, 450 mg/kg at E12.5) ASD mouse model starting from embryonic life, throughout lactation and until adulthood. Maternal and offspring behaviors were investigated as well as several VPA-induced ASD biological features: cerebellar Purkinje cell (PC) number, inflammatory markers, gut microbiota, and peripheral and brain PUFA composition. Developmental milestones were delayed in the n-3 supp group compared to the n-3 bal group in both sexes. Whatever the diet, VPA-exposed offspring did not show ASD characteristic alterations in social behavior, stereotypies, PC number, or gut microbiota dysbiosis while global activity, gait, peripheral and brain PUFA levels as well as cerebellar TNF-alpha levels were differentially altered by diet and treatment according to sex. The current study provides evidence of beneficial effects of n-3 PUFA based diets, including one without LCPUFAs, on preventing several behavioral and cellular symptoms related to ASD.

Effects of different n-6/n-3 polyunsaturated fatty acids ratios on lipid metabolism in patients with hyperlipidemia: a randomized controlled clinical trial

Background and aims

Intake of n-3 polyunsaturated fatty acids (PUFA) is helpful for cardiometabolic health. It improves lipid metabolism, and increasing n-3 PUFA is often considered beneficial. However, the role of n-6/n-3 in the regulation of lipid metabolism has been much debated. Therefore, this study was performed on the effect of different proportions of n-6/n-3 diet on lipid metabolism, and quality of life in patients with hyperlipidemia, aiming to explore appropriate proportions of n-6/n-3 to provide the theoretical basis for the development and application of nutritional blended oil in the future.

Methods

These 75 participants were randomized and assigned into three groups, which received dietary oil with high n-6/n-3 PUFA ratios (HP group: n-6/n-3 = 7.5/1), dietary oil with middle n-6/n-3 PUFA ratios (MP group: n-6/n-3 = 2.5/1) or low n-6/n-3 PUFA ratios (LP group: n-6/n-3 = 1/2.5). All patients received dietary guidance and health education were monitored for hyperlipidemia. Anthropometric, lipid and blood glucose parameters and quality of life were assessed at baseline and 60 days after intervention.

Result

After 60 days, high-density lipoprotein cholesterol (HDL-c) level was increased (p = 0.029) and Total cholesterol (TC) level was decreased (p = 0.003) in the MP group. In the LP group, TC level was decreased (p = 0.001), TG level was decreased (p = 0.001), but HDL-c level was not significantly increased. At the end of intervention, quality of life' score was improved in both MP and LP groups (p = 0.037).

Conclusion

Decreasing the intake of edible oil n-6/n-3 ratio can improve blood lipids and quality of life. This is significant for the prevention of cardiovascular disease (CVD). It is also essential to note that an excessive reduction of the n-6/n-3 ratio does not further improve the blood lipid metabolism. In addition, the application of perilla oil in nutritional blended oil has particular significance.

Clinical trial registration

https://www.chictr.org.cn/indexEN.html, identifier ChiCTR-2300068198.

Comprehensive fecal metabolomics and gut microbiota for the evaluation of the mechanism of Panax Ginseng in the treatment of Qi-deficiency liver cancer

ETHNOPHARMACOLOGICAL RELEVANCE

Qi deficiency liver cancer (QDLC) is an important part of liver cancer research in traditional Chinese medicine (TCM). In the course of its treatment, Panax ginseng is often selected as the main Chinese herbal medicine, and its function has special significance in the tumor treatment of Qi deficiency constitution. However, its mechanism is not clear.

AIM OF THE STUDY

The research tried to evaluate the mechanism of Panax ginseng in the treatment of QDLC through fecal metabonomics and gut microbiota on the basis of previous pharmacodynamic evaluation.

MATERIALS AND METHODS

Firstly, biomarkers and related metabolic pathways were screened and identified by metabonomics and Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Then, 16S rRNA sequencing technique was used to investigate the composition, β diversity and key differences of gut microbiota. Finally, the relationship among phenotypes, gut microbiota and fecal metabolites was comprehensively analyzed by spearman correlation coefficient.

RESULTS

31 pharmacodynamic potential biomarkers and 20 synergistic potential biomarkers of effective parts of Panax ginseng on QDLC were screened and identified by fecal metabonomics. And then, 6 major metabolic pathways were searched, including bile acid biosynthesis, unsaturated fatty acid biosynthesis, tryptophan metabolism, arachidonic acid metabolism, pyrimidine metabolism, vitamin B6 metabolism. In the study of gut microbiota, at the genus level, 25 species of bacteria with significant differences of effective parts on QDLC and 23 species of bacteria with significant differences of synergistic action of ginsenosides and polysaccharides were screened. In addition, Spearman correlation analysis showed that there was a complex potential relationship among phenotype, gut microbiota and fecal metabolites during the development of QDLC and Panax ginseng intervention, which was mainly reflected in the close potential relationship between bacteria and fecal metabolites such as bile acids, unsaturated fatty acids and indole compounds.

CONCLUSION

Through the changes of fecal endogenous metabolites and intestinal bacteria, the mechanism of Panax ginseng on QDLC were preliminarily clarified.

Early overnutrition in male mice negates metabolic benefits of a diet high in monounsaturated and omega-3 fats

Overconsumption of saturated fats promotes obesity and type 2 diabetes. Excess weight gain in early life may be particularly detrimental by promoting earlier diabetes onset and potentially by adversely affecting normal development. In the present study we investigated the effects of dietary fat composition on early overnutrition-induced body weight and glucose regulation in Swiss Webster mice, which show susceptibility to high-fat diet-induced diabetes. We compared glucose homeostasis between a high-fat lard-based (HFL) diet, high in saturated fats, and a high-fat olive oil/fish oil-based (HFO) diet, high in monounsaturated and omega-3 fats. We hypothesized that the healthier fat profile of the latter diet would improve early overnutrition-induced glucose dysregulation. However, early overnutrition HFO pups gained more weight and adiposity and had higher diabetes incidence compared to HFL. In contrast, control pups had less weight gain, adiposity, and lower diabetes incidence. Plasma metabolomics revealed reductions in various phosphatidylcholine species in early overnutrition HFO mice as well as with diabetes. These findings suggest that early overnutrition may negate any beneficial effects of a high-fat diet that favours monounsaturated and omega-3 fats over saturated fats. Thus, quantity, quality, and timing of fat intake throughout life should be considered with respect to metabolic health outcomes.

Perinatal Dietary Polyunsaturated Fatty Acids in Brain Development, Role in Neurodevelopmental Disorders

n-3 and n-6 polyunsaturated fatty acids (PUFAs) are essential fatty acids that are provided by dietary intake. Growing evidence suggests that n-3 and n-6 PUFAs are paramount for brain functions. They constitute crucial elements of cellular membranes, especially in the brain. They are the precursors of several metabolites with different effects on inflammation and neuron outgrowth. Overall, long-chain PUFAs accumulate in the offspring brain during the embryonic and post-natal periods. In this review, we discuss how they accumulate in the developing brain, considering the maternal dietary supply, the polymorphisms of genes involved in their metabolism, and the differences linked to gender. We also report the mechanisms linking their bioavailability in the developing brain, their transfer from the mother to the embryo through the placenta, and their role in brain development. In addition, data on the potential role of altered bioavailability of long-chain n-3 PUFAs in the etiologies of neurodevelopmental diseases, such as autism, attention deficit and hyperactivity disorder, and schizophrenia, are reviewed.

Longitudinal investigation of the relationship between omega-3 polyunsaturated fatty acids and neuropsychological functioning in recent-onset psychosis: A randomized clinical trial

Alterations in polyunsaturated fatty acids (PUFAs), including omega-3 and omega-6, have been implicated in the pathophysiology of psychotic disorders, but little is known about their associations with neuropsychological functioning. The present study includes 46 recent-onset psychosis patients who participated in a larger (n = 50) double blind, placebo-controlled randomized clinical trial comparing 16 weeks of treatment with either risperidone + fish oil (FO) (EPA 740 mg and DHA 400 mg daily) or risperidone + placebo and completed neuropsychological assessments at the baseline timepoint. We investigated the relationship between baseline omega-3 (i.e., eicosapentaenoic acid, EPA; docosapentaenoic acid, DPA and docosahexaenoic acid, DHA) and omega-6 (i.e., arachidonic acid, AA) PUFA with baseline MATRICS Consensus Cognitive Battery (MCCB) and Brief Psychiatric Rating Scale (BPRS) scores. Twenty-five patients had neuropsychological data available at 16 weeks following participation in the clinical trial, which included 12 patients assigned to risperidone + FO and 13 patients assigned to risperidone + placebo. At baseline both higher DHA and EPA correlated significantly with better social cognition after controlling for functioning on other neuropsychological domains, total BPRS score, AA level and substance use. Also, at baseline higher AA correlated significantly with hostility/uncooperativeness after controlling for DHA + EPA + DPA, overall neuropsychological functioning and substance use. Patients treated with risperidone + FO demonstrated a significant longitudinal increase in social cognition that was significantly higher at 16 weeks compared to patients treated with risperidone + placebo. DHA also correlated significantly with social cognition at the 16-week timepoint. This study provides novel evidence for a differential role of omega-3 vs. omega-6 PUFA in neuropsychological deficits and symptoms in recent-onset psychosis and its treatment.

Effects of the linoleic acid/docosahexaenoic acid ratio and concentration inducing autophagy in Raw264.7 cells against Staphylococcus aureus

Our study was to understand the autophagy induce by different ratios and concentrations of LA/DHA on Raw264.7 cell, and then to investigate the effect of Raw264.7 autophagy on the clearance of Staphylococcus aureus. Raw264.7 cells was treated by LA/DHA in different concentrations (50/100 µmol/L) and ratios (4:1, 6:1, 8:1, 1:4, 1:6 and 1:8) for 6/12/24 h, cell viability assay was assessed by Cell Counting Kit-8, LC3B, p62, P-mTOR, P-Akt, P-PI3K and BECN 1 were detected by the Western blot. LA/DHA could induce autophagy of Raw264.7 cells through the PI3K-Akt-mTOR signaling pathway, the strong effect on autophagy by the concentration is 100 µmol/L, the ratio is 6:1 of LA/DHA, and the treatment time is 24 h. Compared with the images in the control group obtained by merging red and green fluorescence channels, the treatment of LA, DHA in a ratio of 6:1 at a concentration of 100 µmol/L for 24 h significantly lead to a substantial number of autophagosomes (yellow) as well as autolysosomes (red), enhancing autophagy flux. Autophagy induce by LA/DHA can devour and damage intracellular and extracellular Staphylococcus aureus. These results indicate that LA/DHA cloud induce autophagy and enhance the phagocytosis and killing ability of macrophages to intracellular parasitic bacteria.

Effects of dietary fatty acids on the social life of male Guinea pigs from adolescence to adulthood

Dietary intake of polyunsaturated fatty acids (PUFAs) or saturated fatty acids (SFAs) differently modulates neurophysiological and behavioral functions in response to altered hypothalamic-pituitary-adrenal (HPA)-axis activity and an individual's development. In this context, an individual's social environment, including social interactions and social hierarchies, is closely related to hormone concentrations and possibly interacts with dietary fatty acid effects. We investigated if dietary supplementation with walnut oil (high in PUFAs) and coconut fat (high in SFAs), compared to a control group, affects body mass gain, cortisol and testosterone concentrations, plasma fatty acids, and social behavior in male domestic guinea pigs from adolescence to adulthood. For analyses of cortisol and testosterone concentrations, social interactions were included as covariates in order to consider effects of social behavior on hormone concentrations. Our results revealed that SFAs increased escalated conflicts like fights and stimulated cortisol and testosterone concentrations, which limited body mass gain and first-year survival. PUFAs did not remarkably affect social behavior and hormone concentrations, but enabled the strongest body mass gain, which probably resulted from an energetic advantage. Neither sociopositive nor agonistic behaviors explained age-specific differences in hormone concentrations between groups. However, a high number of subdominant individuals and lower testosterone concentrations were related to increased cortisol concentrations in adult PUFA males. Our findings demonstrate the importance of dietary fatty acids regarding behavioral and endocrine developmental processes and adaptations to the social environment by modulating HPA-axis function and body homeostasis.

Loss of RAR-related orphan receptor alpha (RORα) selectively lowers docosahexaenoic acid in developing cerebellum

Deficiency in retinoid acid receptor-related orphan receptor alpha (RORα) of staggerer mice results in extensive granule and Purkinje cell loss in the cerebellum as well as in learned motor deficits, cognition impairments and perseverative tendencies that are commonly observed in autistic spectrum disorder (ASD). The effects of RORα on brain lipid metabolism associated with cerebellar atrophy remain unexplored. The aim of this study is to examine the effects of RORα deficiency on brain phospholipid fatty acid concentrations and compositions. Staggerer mice (Rora^sg/sg) and wildtype littermates (Rora^+/+) were fed n-3 polyunsaturated fatty acids (PUFA) containing diets ad libitum. At 2 months and 7 or more months old, brain total phospholipid fatty acids were quantified by gas chromatography-flame ionization detection. In the cerebellum, all fatty acid concentrations were reduced in 2 months old mice. Since total fatty acid concentrations were significantly different at 2-month-old, we examined changes in fatty acid composition. The composition of ARA was not significantly different between genotypes; though DHA composition remained significantly lowered. Despite cerebellar atrophy at >7-months-old, cerebellar fatty acid concentrations had recovered comparably to wildtype control. Therefore, RORα may be necessary for fatty acid accretions during neurodevelopment. Specifically, the effects of RORα on PUFA metabolisms are region-specific and age-dependent.

Ether Lipid Deficiency in Mice Produces a Complex Behavioral Phenotype Mimicking Aspects of Human Psychiatric Disorders

Ether lipids form a specialized subgroup of phospholipids that requires peroxisomes to be synthesized. We have previously detected that deficiency in these lipids leads to a severe disturbance of neurotransmitter homeostasis and release as well as behavioral abnormalities, such as hyperactivity, in a mouse model. Here, we focused on a more detailed examination of the behavioral phenotype of ether lipid-deficient mice (Gnpat KO) and describe a set of features related to human psychiatric disorders. Gnpat KO mice show strongly impaired social interaction as well as nestlet shredding and marble burying, indicating disturbed execution of inborn behavioral patterns. Also, compromised contextual and cued fear conditioning in these animals suggests a considerable memory deficit, thus potentially forming a connection to the previously determined ether lipid deficit in human patients with Alzheimer's disease. Nesting behavior and the preference for social novelty proved normal in ether lipid-deficient mice. In addition, we detected task-specific alterations in paradigms assessing depression- and anxiety-related behavior. The reported behavioral changes may be used as easy readout for the success of novel treatment strategies against ether lipid deficiency in ameliorating nervous system-associated symptoms. Furthermore, our findings underline that ether lipids are paramount for brain function and demonstrate their relevance for cognitive, social, and emotional behavior. We hereby substantially extend previous observations suggesting a link between deficiency in ether lipids and human mental illnesses, particularly autism and attention-deficit hyperactivity disorder.