A Comparative Study about the Neuroprotective Effects of DHA-Enriched Phosphatidylserine and EPA-Enriched Phosphatidylserine against Oxidative Damage in Primary Hippocampal Neurons

Evaluating the healing effects of docosahexaenoic acid in neonates with bilirubin-induced brain injury

BACKGROUND

Neonatal brain injury due to bilirubin toxicity presents critical need for effective healing treatments. Docosahexaenoic acid (DHA), having neuroprotective properties, offers potential therapeutic benefits in promoting brain repair and recovery.

OBJECTIVES

This study focused on evaluating the healing capabilities of DHA in neonatal brains damaged by bilirubin-induced injury, with particular attention to its role in enhancing brain tissue repair mechanisms.

METHODS

Employing the bilirubin encephalopathy model in neonatal Sprague-Dawley rats and neuronal cell cultures, we investigated the therapeutic impact of DHA.

RESULTS

The study measured improvements in brain tissue integrity, assessed bilirubin levels, analyzed gene and protein expressions pertinent to the brain's recovery process. DHA administration resulted in significant repair in neonatal brains, evidenced by reduction in bilirubin levels and restoration of normal brain tissue architecture.

CONCLUSION

Molecular analysis indicated the distinct modulation of the CTBP1/miR-155-5p/KDM5A pathway, critical for cellular repair processes and marked decrease in markers of cellular damage and stress.

Liposomes as versatile agents for the management of traumatic and nontraumatic central nervous system disorders: drug stability, targeting efficiency, and safety

Various nanoparticle-based drug delivery systems for the treatment of neurological disorders have been widely studied. However, their inability to cross the blood-brain barrier hampers the clinical translation of these therapeutic strategies. Liposomes are nanoparticles composed of lipid bilayers, which can effectively encapsulate drugs and improve drug delivery across the blood-brain barrier and into brain tissue through their targeting and permeability. Therefore, they can potentially treat traumatic and nontraumatic central nervous system diseases. In this review, we outlined the common properties and preparation methods of liposomes, including thin-film hydration, reverse-phase evaporation, solvent injection techniques, detergent removal methods, and microfluidics techniques. Afterwards, we comprehensively discussed the current applications of liposomes in central nervous system diseases, such as Alzheimer's disease, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis, traumatic brain injury, spinal cord injury, and brain tumors. Most studies related to liposomes are still in the laboratory stage and have not yet entered clinical trials. Additionally, their application as drug delivery systems in clinical practice faces challenges such as drug stability, targeting efficiency, and safety. Therefore, we proposed development strategies related to liposomes to further promote their development in neurological disease research.

Fucoxanthin promotes the conversion efficiency of alpha-linolenic acid in feeding to docosahexaenoic acid in quail egg yolk

The conversion of alpha-linolenic acid (ALA) in feed to DHA in egg is inefficient, so there is a critical need for feed additives that can enhance the enrichment of docosahexaenoic acid (DHA) in egg yolk from ALA-rich feed. The present study evaluated the impact of dietary fucoxanthin on the conversion efficiency of ALA in feed to DHA in quail egg yolk. Results showed that the addition of 0.02 % fucoxanthin to the diet supplemented with 0.5 % ALA significantly enhanced the DHA conversion rate by 51.48 % and increased DHA content by 32.82 %, matching levels observed with 1 % ALA supplementation during the peak laying period. Importantly, fucoxanthin did not alter the proportion of phospholipid-bound DHA. These findings suggest that fucoxanthin, as a feed additive, has the potential to promote the accumulation of DHA in avian eggs when supplemented with ALA in feed.

Investigate the protective effects of eicosapentaenoic acid in human astrocytes of oxidative stress damage and explore its underlying mechanisms

BACKGROUND

The importance of fatty acids in human health and their potential in treating various brain diseases is increasingly acknowledged. Research indicates that ultra-long-chain fatty acids adversely affect dietary habits, while omega (ω)-3 polyunsaturated fatty acids confer health benefits. Eicosapentaenoic acid (EPA), an ω-3 polyunsaturated fatty acid, manifests diverse protective activities, including anti-oxidative effects and the attenuation of brain diseases. Previous studies have suggested that EPA can alleviate oxidative stress and forestall diseases stemming from oxidative damage. Nevertheless, EPA's precise antioxidant mechanism and signaling pathway in human astrocytes remain elusive. To address this knowledge gap, we established an H2O2-induced oxidative damage model in Gibco® Human Astrocytes (GHA cells) and elucidated the underlying mechanisms and signaling pathways.

METHODS AND RESULTS

Our assessments included cell viability through the CCK-8 assay, morphological examination via microscopy, ROS quantification using the DCFH-DA fluorescent probe, GSH content evaluation with the CMF-DA fluorescent probe, and protein expression analysis for antioxidant and apoptotic markers through Western blotting. The results showed that pretreatment with 3 µM of EPA countered the cytotoxicity, ROS production, and GSH depletion caused by H2O2 (250 µM) in GHA cells. Additionally, EPA pretreatment effectively reduced the cytotoxicity and oxidative stress resulting from H2O2 by modulating the Nrf2/HO-1/NQO1 and Bax/Bcl-2/caspase-9/caspase-3 signaling pathways in GHA cells.

CONCLUSION

These findings enhance our understanding of EPA's antioxidant mechanisms in the oxidative stress model of human astrocytes, illuminate the interplay between antioxidant and apoptotic signals, and offer promise for exploring potential preventive and therapeutic interventions for brain diseases.

The Effects and Mechanisms of n-3 and n-6 Polyunsaturated Fatty Acids in the Central Nervous System

The brain is rich in fatty acids (FAs), with polyunsaturated fatty acids (PUFAs), such as docosahexaenoic acid (C22:6n-3, DHA) and arachidonic acid (C20:4n-6, ARA), and the former predominantly stored in the form of phosphatidylcholine, phosphatidyl ethanolamine (PE, diacyl and plasma phospholipid proform), and phosphatidylserine (PS), while the latter is mainly found in ethanolamine phosphoglycerides (EPG) and contributes to constitute most of phosphoglycerides. When required by the body, PUFAs are liberated from membrane phospholipids (either directly or via their metabolites, which are generated by a series of enzymatic reactions) to participate in various cerebral physiological processes. PUFAs and their derivatives play crucial roles in modulating numerous bodily functions, including neuronal signal transmission, neurogenesis, neuroinflammation, and glucose uptake in the brain, thereby sustaining fundamental brain function. Although PUFAs have been implicated in a spectrum of neurological disorders, including acute brain injury (TBI), multiple sclerosis (MS), and neurodegenerative diseases, their role in conditions such as depression, Alzheimer's disease (AD), and Parkinson's disease (PD) is particularly noteworthy. These disorders are closely linked to critical brain functions, including cognition, memory, and inflammatory processes. Given the substantial body of research elucidating the involvement of PUFAs in the pathogenesis and progression of these diseases, this review will specifically concentrate on their impact within these contexts.

Understanding of Alzheimer's disease pathophysiology for therapeutic implications of natural products as neuroprotective agents

Alzheimer's disease (AD) is a leading cause of dementia, affecting more than 24.3 million people worldwide in 2024. Sporadic AD (SAD) is more common and occurs in the geriatric population, while familial AD (FAD) is rare and appears before the age of 65 years. Due to progressive cholinergic neuronal loss and modulation in the PKC/MAPK pathway, β-secretase gets upregulated, leading to Aβ aggregation, which further activates tau kinases that form neurofibrillary tangles (NFT). Simultaneously, antioxidant enzymes are also upregulated, increasing oxidative stress (OS) and reactive species by impairing mitochondrial function, leading to DNA damage and cell death. This review discusses the classifications and components of several natural products (NPs) that target these signaling pathways for AD treatment. NPs, including alkaloids, polyphenols, flavonoids, polysaccharides, steroids, fatty acids, tannins, and polypeptides derived from plants, microbes, marine animals, venoms, insects, and mushrooms, are explored in detail. A synergistic combination of plant metabolites, together with prebiotics and probiotics has been shown to decrease Aβ aggregates by increasing the production of bioactive compounds. Toxins derived from venomous organisms have demonstrated effectiveness in modulating signaling pathways and reducing OS. Marine metabolites have also shown neuroprotective and anti-inflammatory properties. The cholera toxin B subunit and an Aβ15 fragment have been combined to create a possible oral AD vaccine, that showed enhancement of cognitive function in mice. Insect tea is also a reliable source of antioxidants. A functional edible mushroom snack bar showed an increment in cognitive markers. Future directions and therapeutic approaches for the treatment of AD can be improved by focusing more on NPs derived from these sources.

The Advancements of Marine Natural Products in the Treatment of Alzheimer's Disease: A Study Based on Cell and Animal Experiments

As life expectancy rises and the aging population grows, Alzheimer's disease (AD) has become a significant global health concern. AD is a complex neurodegenerative disorder with an unclear etiology. Current hypotheses primarily focus on β-amyloid (Aβ) aggregation, tau protein hyperphosphorylation, and neuroinflammation as key pathological processes. Given the limited efficacy of existing therapeutic strategies, there is an urgent need to explore novel treatment options. Marine natural products have garnered significant attention due to their unique chemical structures and diverse bioactivities, demonstrating potential for multi-target interventions in AD. This review systematically summarizes the roles of marine-derived compounds, including polysaccharides, carotenoids, and polyphenols, in modulating Aβ aggregation, mitigating tau protein pathology, and regulating gut-brain axis dysfunction. Furthermore, the challenges of current research are discussed, with an emphasis on improving blood-brain barrier permeability and optimizing drug delivery systems to facilitate clinical translation.

Lipidomics Analysis Reveals the Effects of Docosahexaenoic Acid from Different Sources on Prefrontal-Cortex Synaptic Plasticity

BACKGROUND

Docosahexaenoic Acid (DHA) is an extensively used nutrition supplement in dairy food because of its beneficial effects on cognition. To find an effective DHA intervention for the synapses in the cortex during this period, this study aimed to use targeted lipidomics to evaluate the lipid composition of prefrontal-cortex (PFC) tissue in different DHA interference methods.

METHODS

Analyzed samples were taken from interfering feeding Bama pigs (BPs) (3 months) fed with soybean oil (Group B), blended oil (Group M), naturally DHA-supplemented milk with blended oil (Group OM), and DHA from fish oil (FO) with blended oil (Group Y). We also examined the protein expression levels of BDNF, GAP43, and MBP.

RESULTS

The lipidomics analysis identified 80 different related negative-ion lipid content and filtered the biomarker lipids in PFC tissue. We observed significant lipid composition changes between group Y and other groups, especially for content levels of phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylinositol (PI), phosphatidylserine (PS), and sphingomyelin (SM). The same observations were made from mRNA and protein expressions related to lipid transportation, phosphatidylserine (PS) synthetase, and synaptic plasticity in PFC tissues between group Y and other groups, including the mRNA expression levels of CD36, BDNF, and PTDSS1. The analysis of protein expression levels showed that the metabolism mode of DHA intervention from FO benefited the PFC, PS metabolism, and PFC synaptic plasticity of infants.

CONCLUSIONS

The results highlight further prospects for the DHA intervention mode, which provides new routes for other studies on polyunsaturated-fatty-acid (PUFA) interference for infants.

Effects of APOE4 on omega-3 brain metabolism across the lifespan

Omega-3 (n-3) polyunsaturated fatty acids (PUFAs), such as docosahexaenoic acid (DHA), have important roles in human nutrition and brain health by promoting neuronal functions, maintaining inflammatory homeostasis, and providing structural integrity. As Alzheimer's disease (AD) pathology progresses, DHA metabolism in the brain becomes dysregulated, the timing and extent of which may be influenced by the apolipoprotein E ε4 (APOE4) allele. Here, we discuss how maintaining adequate DHA intake early in life may slow the progression to AD dementia in cognitively normal individuals with APOE4, how recent advances in DHA brain imaging could offer insights leading to more personalized preventive strategies, and how alternative strategies targeting PUFA metabolism pathways may be more effective in mitigating disease progression in patients with existing AD dementia.

Trimethylamine N-Oxide in Aquatic Foods

Trimethylamine N-oxide (TMAO), a characteristic nonprotein nitrogen compound, is widely present in seafood, which exhibits osmoregulatory effects for marine organisms in vivo and plays an important role in aquaculture and aquatic product preservation. However, much attention has been focused on the negative effect of TMAO since it has recently emerged as a putative promoter of chronic diseases. To get full knowledge and maximize our ability to balance the positive and negative aspects of TMAO, in this review, we comprehensively discuss the TMAO in aquatic products from the aspects of physiological functions for marine organisms, flavor, quality, the conversion of precursors, the influences on human health, and the seafood ingredients interaction consideration. Though the circulating TMAO level is inevitably enhanced after seafood consumption, dietary seafood still exhibits beneficial health effects and may provide nutraceuticals to balance the possible adverse effects of TMAO.

Myricanol improves metabolic profiles in dexamethasone induced lipid and protein metabolism disorders in mice

Myricanol (MY) is one of the main active components from bark of Myrica Rubra. It is demonstrated that MY rescues dexamethasone (DEX)-induced muscle dysfunction via activating silent information regulator 1 (SIRT1) and increasing adenosine 5'-monophosphate-activated protein kinase (AMPK) phosphorylation. Since SIRT1 and AMPK are widely involved in the metabolism of nutrients, we speculated that MY may exert beneficial effects on DEX-induced metabolic disorders. This study for the first time applied widely targeted metabolomics to investigate the beneficial effects of MY on glucose, lipids, and protein metabolism in DEX-induced metabolic abnormality in mice. The results showed that MY significantly reversed DEX-induced soleus and gastrocnemius muscle weight loss, muscle fiber damage, and muscle strength loss. MY alleviated DEX-induced metabolic disorders by increasing SIRT1 and glucose transporter type 4 (GLUT4) expressions. Additionally, myricanol prevented muscle cell apoptosis and atrophy by inhibiting caspase 3 cleavages and muscle ring-finger protein-1 (MuRF1) expression. Metabolomics showed that MY treatment reversed the serum content of carnitine ph-C1, palmitoleic acid, PS (16:0_17:0), PC (14:0_20:5), PE (P-18:1_16:1), Cer (t18:2/38:1(2OH)), four amino acids and their metabolites, and 16 glycerolipids in DEX mice. Kyoto encyclopedia of genes and genomes (KEGG) and metabolic set enrichment analysis (MSEA) analysis revealed that MY mainly affected metabolic pathways, glycerolipid metabolism, lipolysis, fat digestion and absorption, lipid and atherosclerosis, and cholesterol metabolism pathways through regulation of metabolites involved in glutathione, butanoate, vitamin B6, glycine, serine and threonine, arachidonic acid, and riboflavin metabolism. Collectively, MY can be used as an attractive therapeutic agent for DEX-induced metabolic abnormalities.

Sex, Body Mass Index, and APOE4 Increase Plasma Phospholipid-Eicosapentaenoic Acid Response During an ω-3 Fatty Acid Supplementation: A Secondary Analysis

BACKGROUND

The brain is concentrated with omega (ω)-3 (n-3) fatty acids (FAs), and these FAs must come from the plasma pool. The 2 main ω-3 FAs, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), must be in the form of nonesterified fatty acid (NEFA) or esterified within phospholipids (PLs) to reach the brain. We hypothesized that the plasma concentrations of these ω-3 FAs can be modulated by sex, body mass index (BMI, kg/m2), age, and the presence of the apolipoprotein (APO) E-ε4 allele in response to the supplementation.

OBJECTIVES

This secondary analysis aimed to determine the concentration of EPA and DHA within plasma PL and in the NEFA form after an ω-3 FA or a placebo supplementation and to investigate whether the factors change the response to the supplement.

METHODS

A randomized, double-blind, placebo-controlled trial was conducted. Participants were randomly assigned to either an ω-3 FA supplement (DHA 0.8 g and EPA 1.7 g daily) or to a placebo for 6 mo. FAs from fasting plasma samples were extracted and subsequently separated into PLs with esterified FAs and NEFAs using solid-phase extraction. DHA and EPA concentrations in plasma PLs and as NEFAs were quantified using gas chromatography.

RESULTS

EPA and DHA concentrations in the NEFA pool significantly increased by 31%-71% and 42%-82%, respectively, after 1 and 6 mo of ω-3 FA supplementation. No factors influenced plasma DHA and EPA responses in the NEFA pool. In the plasma PL pool, DHA increased by 83%-109% and EPA by 387%-463% after 1 and 6 mo of ω-3 FA supplementation. APOE4 carriers, females, and individuals with a BMI of ≤25 had higher EPA concentrations than noncarriers, males, and those with a BMI of >25, respectively.

CONCLUSIONS

The concentration of EPA in plasma PLs are modulated by APOE4, sex, and BMI. These factors should be considered when designing clinical trials involving ω-3 FA supplementation. This trial was registered at clinicaltrials.gov as NCT01625195.

Transcriptomic atlas of midbrain dopamine neurons uncovers differential vulnerability in a Parkinsonism lesion model

Midbrain dopamine (mDA) neurons comprise diverse cells with unique innervation targets and functions. This is illustrated by the selective sensitivity of mDA neurons of the substantia nigra compacta (SNc) in patients with Parkinson's disease, while those in the ventral tegmental area (VTA) are relatively spared. Here, we used single nuclei RNA sequencing (snRNA-seq) of approximately 70,000 mouse midbrain cells to build a high-resolution atlas of mouse mDA neuron diversity at the molecular level. The results showed that differences between mDA neuron groups could best be understood as a continuum without sharp differences between subtypes. Thus, we assigned mDA neurons to several 'territories' and 'neighborhoods' within a shifting gene expression landscape where boundaries are gradual rather than discrete. Based on the enriched gene expression patterns of these territories and neighborhoods, we were able to localize them in the adult mouse midbrain. Moreover, because the underlying mechanisms for the variable sensitivities of diverse mDA neurons to pathological insults are not well understood, we analyzed surviving neurons after partial 6-hydroxydopamine (6-OHDA) lesions to unravel gene expression patterns that correlate with mDA neuron vulnerability and resilience. Together, this atlas provides a basis for further studies on the neurophysiological role of mDA neurons in health and disease.