Krill phosphatidylserine improves learning and memory in Morris water maze in aged rats

Lipidomics and mass spectrometry imaging unveil alterations in mice hippocampus lipid composition exposed to hypoxia

Lipids are components of cytomembranes that are involved in various biochemical processes. High-altitude hypoxic environments not only affect the body's energy metabolism, but these environments can also cause abnormal lipid metabolism involved in the hypoxia-induced cognitive impairment. Thus, comprehensive lipidomic profiling of the brain tissue is an essential step toward understanding the mechanism of cognitive impairment induced by hypoxic exposure. In the present study, mice showed reduced new-object recognition and spatial memory when exposed to hypobaric hypoxia for 1 day. Histomorphological staining revealed significant morphological and structural damage to the hippocampal tissue, along with prolonged exposure to hypobaric hypoxia. Dynamic lipidomics of the mouse hippocampus showed a significant shift in both the type and distribution of phospholipids, as verified by spatial lipid mapping. Collectively, a diverse and dynamic lipid composition in mice hippocampus was uncovered, which deepens our understanding of biochemical changes during sustained hypoxic exposure and could provide new insights into the cognitive decline induced by high-altitude hypoxia exposure.

A Randomized, Double-Blind, Placebo-Controlled, Parallel Study Investigating the Efficacy of a Whole Coffee Cherry Extract and Phosphatidylserine Formulation on Cognitive Performance of Healthy Adults with Self-Perceived Memory Problems

INTRODUCTION

Cognition refers to brain functions including memory, learning, and thought processing and is increasingly important to individuals. However, impairment of cognitive function is a concern among North American adults. Therefore, effective and reliable treatments are needed.

METHODS

This randomized, double-blind, placebo-controlled study examined the effects of 42 days of Neuriva® supplementation, a whole coffee cherry extract and phosphatidylserine supplement, on memory, accuracy, focus and concentration and learning among 138 healthy adults (40-65 years) with self-reported memory problems. Plasma brain-derived neurotrophic factor (BDNF) levels, Computerized Mental Performance Assessment System (COMPASS) tasks, the Everyday Memory Questionnaire (EMQ), and Go/No-Go tests were assessed at baseline and day 42.

RESULTS

As compared to placebo, Neuriva® supplementation elicited greater improvements at day 42 in numeric working memory COMPASS task accuracy outcomes (p ≤ 0.024) which assessed memory, accuracy, and focus and concentration, and reaction time outcomes (p ≤ 0.031) which assessed memory as well as focus and concentration. Neuriva® supplementation improved overall accuracy (p = 0.035) in the picture recognition task that assessed memory, accuracy, and learning compared to placebo. No significant differences between groups were observed for BDNF, the EMQ, or Go/No-Go tests.

CONCLUSION

Results suggest 42 days of Neuriva® supplementation was safe, well tolerated, and beneficial in improving memory, accuracy, focus and concentration, and learning in a healthy adult population with self-reported memory problems.

Menaquinone-7 ameliorates cerebrovascular calcification-associated memory decline in aged mice

Menaquinone (MK)-7 is a vitamin K2 analog that functions as a cofactor of γ-glutamyl carboxylase involved in the activation of vitamin K (VK)-dependent proteins. The present study aimed to evaluate the effect of MK-7 on memory and cognitive function in aged C57BL/6 mice. Eighteen-month-old mice were raised for a further 4 months, fed on a standard or calcium-rich diet (3 % [w/w]), and were orally given MK-7 (40 and 400 μg/day/mouse) five times per week during the same period. The Morris water maze (MWM) test was performed at 19 and 22 months. The aged mice showed noticeable memory declines in the MWM test at all time points compared with 6-week-old mice, and this memory loss was significantly restored by the daily administration of high-dose MK-7 for 4 months. MK-7 administration also improved micro-computed tomography-based cerebrovascular calcification and aging-associated declines in growth arrest-specific 6, total and carboxylated matrix Gla proteins, and ganglioside levels in the brain of aged mice. It serologically reduced phosphorous levels in the blood, but not the urea, cholesterol, and calcium. Taken together, the long-term administration of MK-7 significantly improved age-related memory and cognitive impairments, possibly through inhibition of cerebrovascular calcification in aged mice, indicating that it can be used to develop new drugs for improving memory and cognitive function in older adults.

Peanut meal extract fermented with Bacillus natto attenuates physiological and behavioral deficits in a D-galactose-induced aging rat model

Our previous studies have shown that the nutritional properties of peanut meal after fermentation are markedly improved. In this study, in order to facilitate the further utilization of peanut meal, we investigated the effects of its fermentation extract by Bacillus natto (FE) on cognitive ability, antioxidant activity of brain, and protein expression of hippocampus of aging rats induced by D-galactose. Seventy-two female SD rats aged 4-5 months were randomly divided into six groups: normal control group (N), aging model group (M), FE low-dose group (FL), FE medium-dose group (FM), FE high-dose group (FH) and vitamin E positive control group (Y). Morris water maze (MWM) test was performed to evaluate their effects on learning and memory ability in aging rats. SOD activity and malondialdehyde (MDA) content of brain, HE staining and the expression of γ-aminobutyric acid receptor 1 (GABABR1) and N-methyl-D-aspartic acid 2B receptor (NMDAR2B) in the hippocampus of rats were measured. The results show that FE supplementation can effectively alleviate the decrease of thymus index induced by aging, decrease the escape latency of MWM by 66.06%, brain MDA by 28.04%, hippocampus GABABR1 expression by 7.98%, and increase brain SOD by 63.54% in aging model rats. This study provides evidence for its anti-aging effects and is a research basis for potential nutritional benefits of underutilized food by-products.

Effects of Dietary Food Components on Cognitive Functions in Older Adults

Population aging has recently been an important issue as the number of elderly people is growing worldwide every year, and the extension of social security costs is financially costly. The increase in the number of elderly people with cognitive decline is a serious problem related to the aging of populations. Therefore, it is necessary to consider not only physical care but also cognitive patterns in the future care of older adults. Since food contains a variety of bioactive substances, dietary patterns may help improve age-related cognitive decline. However, the relationship between cognitive function and individual food components remains ambiguous as no clear efficacy or mechanism has been confirmed. Against this background, this review summarizes previous reports on the biological process of cognitive decline in the elderly and the relationship between individual compounds in foods and cognitive function, as well as the role of individual components of food in cognitive function, in the following order: lipids, carotenoids, vitamins, phenolic compounds, amino acids, peptides, and proteins. Based on the research presented in this review, a proper diet that preserves cognitive function has the potential to improve age-related cognitive decline, Alzheimer's disease, and Parkinson's disease. Hopefully, this review will help to trigger the development of new foods and technologies that improve aging and cognitive functions and extend the healthy life span.

Advances in Technologies for Highly Active Omega-3 Fatty Acids from Krill Oil: Clinical Applications

Euphausia superba, commonly known as krill, is a small marine crustacean from the Antarctic Ocean that plays an important role in the marine ecosystem, serving as feed for most fish. It is a known source of highly bioavailable omega-3 polyunsaturated fatty acids (eicosapentaenoic acid and docosahexaenoic acid). In preclinical studies, krill oil showed metabolic, anti-inflammatory, neuroprotective and chemo preventive effects, while in clinical trials it showed significant metabolic, vascular and ergogenic actions. Solvent extraction is the most conventional method to obtain krill oil. However, different solvents must be used to extract all lipids from krill because of the diversity of the polarities of the lipid compounds in the biomass. This review aims to provide an overview of the chemical composition, bioavailability and bioaccessibility of krill oil, as well as the mechanisms of action, classic and non-conventional extraction techniques, health benefits and current applications of this marine crustacean.

The impact of quetiapine on the brain lipidome in a cuprizone-induced mouse model of schizophrenia

The antipsychotic effect of Quetiapine (Que) has been extensively studied and growing evidence suggests that Que has a beneficial effect, improving cognitive functions and promoting myelin repair. However, the effects of Que on the brain lipidome and the association between Que-associated cognitive improvement and changes in lipids remain elusive. In the present study, we assessed the cognitive protective effects of Que treatment and used a mass spectrometry-based lipidomic approach to evaluated changes in lipid composition in the hippocampus, prefrontal cortex (PFC), and striatum in a mouse model of cuprizone (CPZ)-induced demyelination. CPZ induces cognitive impairment and remarkable lipid changes in the brain, specifically in lipid species of glycerophospholipids and sphingolipids. Moreover, the changes in lipid classes of the PFC were more extensive than those observed in the hippocampus and striatum. Notably, Que treatment ameliorated cuprizone-induced cognitive impairment and partly normalized CPZ-induced lipid changes. Taken together, our data suggest that Que may rescue cognitive behavioral changes from CPZ-induced demyelination through modulation of the brain lipidome, providing new insights into the pharmacological mechanism of Que for schizophrenia.

Neuroprotective Effect of Bean Phosphatidylserine on TMT-Induced Memory Deficits in a Rat Model

BACKGROUND

Trimethyltin (TMT) is a potent neurotoxin affecting various regions of the central nervous system, including the neocortex, the cerebellum, and the hippocampus. Phosphatidylserine (PS) is a membrane phospholipid, which is vital to brain cells. We analyzed the neuroprotective effects of soybean-derived phosphatidylserine (Bean-PS) on cognitive function, changes in the central cholinergic systems, and neural activity in TMT-induced memory deficits in a rat model.

METHODS

The rats were randomly divided into an untreated normal group, a TMT group (injected with TMT + vehicle), and a group injected with TMT + Bean-PS. The rats were treated with 10% hexane (TMT group) or TMT + Bean-PS (50 mg·kg-1, oral administration (p.o.)) daily for 21 days, following a single injection of TMT (8.0 mg/kg, intraperitoneally (i.p.)). The cognitive function of Bean-PS was assessed using the Morris water maze (MWM) test and a passive avoidance task (PAT). The expression of acetylcholine transferase (ChAT) and acetylcholinesterase (AchE) in the hippocampus was assessed via immunohistochemistry. A positron emission tomography (PET) scan was used to measure the glucose uptake in the rat brain.

RESULTS

Treatment with Bean-PS enhanced memory function in the Morris water maze (MWM) test. Consistent with the behavioral results, treatment with Bean-PS diminished the damage to cholinergic cells in the hippocampus, in contrast to those of the TMT group. The TMT+Bean-PS group showed elevated glucose uptake in the frontal lobe of the rat brain.

CONCLUSION

These results demonstrate that Bean-PS protects against TMT-induced learning and memory impairment. As such, Bean-PS represents a potential treatment for neurodegenerative disorders, such as Alzheimer's disease.

Metformin loaded phosphatidylserine nanoliposomes improve memory deficit and reduce neuroinflammation in streptozotocin-induced Alzheimer's disease model

Alzheimer's disease (AD) is closely associated with neuroinflammation development in the brain. Co-delivery of metformin (MET) with phosphatidylserine liposomes neuroprotectant may be beneficial in ameliorating AD-related symptoms like memory impairment and inflammation. Therefore, we aimed to prepare metformin containing phosphatidylserine nanoliposomes formulation (MET-PSL) and to evaluate its effect on rats subjected to AD. Alzheimer's disease model was induced by bilateral intracerebroventricular injection of streptozotocin (3 mg/kg) into rat brains using the stereotactic technique. MET-PSL, MET, and PSL alone were administered intraperitoneally to AD-induced animals and factors including learning and memory storage in addition to cytokine and tissue inflammatory changes were evaluated after a 22-day experiment period. The learning and memory parameters significantly (P < 0.05) improved in AD-rats treated with MET-PSL. Moreover, MET-PSL administration significantly (P < 0.05) decreased cytokine levels of IL1-β, TNF-α, and TGF-β in hippocampal tissues of rats with AD. Histological results indicated a considerable reduction in inflammatory and necrotic neural cells along with significantly (P < 0.05) increased neurogenesis in MET-PSL treated rats. Furthermore, our results showed that MET-PSL formulation could potentially act better than the free form of MET and PSL alone in the recovery process of rats with AD. In general, our data suggest that combination therapy of metformin loaded phosphatidylserine liposomes may enhance the therapeutic performance in AD patients of a clinical study.

The Combination Effects of Resveratrol and Swimming HIIT Exercise on Novel Object Recognition and Open-field Tasks in Aged Rats

INTRODUCTION

Resveratrol, a natural polyphenol abundant in grapes and red wine, has been reported to exert numerous beneficial health effects in the body. High-Intensity Interval Exercise (HIIT) is a form of interval training that provides improved athletic capacity and has a protective effect on health. The purpose of this study was to investigate the interactive effects of swimming HIIT and Resveratrol supplementation on behavioral function in Novel object recognition and open-field tests in aged rats.

METHODS

A total of 45 aged male Wistar rats with an age of 20 months were randomly assigned into five groups of control (C), swimming HIIT (SW-HIIT), swimming HIIT with Resveratrol supplementation (SW-HIIT-R), Resveratrol supplementation (R), and solvent of Resveratrol supplementation (SR). There was also another group that included young animals (2-month-old) and was used to compare with older animals. Swimming HIIT and Resveratrol supplementation groups performed the exercise and received Resveratrol (10 mg/kg/day, gavage) for six weeks. Novel object recognition and open-field tests were used for evaluating the behavioral functions in animals.

RESULTS

The results showed that HIIT and Resveratrol significantly improved recognition memory compared to old animals. Moreover, it seems that HIIT and Resveratrol partly could modulate anxiety-like behaviors compared to old animals in the open-field test.

The effect of phosphatidylserine containing Omega3 fatty-acids on attention-deficit hyperactivity disorder symptoms in children: A double-blind placebo-controlled trial, followed by an open-label extension

Objective

To study the efficacy and safety of phosphatidylserine (PS) containing Omega3 long-chain polyunsaturated fatty acids attached to its backbone (PS-Omega3) in reducing attention-deficit/ hyperactivity disorder (ADHD) symptoms in children.

Method

A 15-week, double-blind, placebo-controlled phase followed by an open-label extension of additional 15 weeks. Two hundred ADHD children were randomized to receive either PS-Omega3 or placebo, out of them, 150 children continued into the extension. Efficacy was assessed using Conners’ parent and teacher rating scales (CRS-P,T), Strengths and Difficulties Questionnaire (SDQ), and Child Health Questionnaire (CHQ). Safety evaluation included adverse events monitoring.

Results

The key finding of the double-blind phase was the significant reduction in the Global:Restless/impulsive subscale of CRS-P and the significant improvement in Parent impact-emotional (PE) subscale of the CHQ, both in the PS-Omega3 group. Exploratory subgroup analysis of children with a more pronounced hyperactive/impulsive behavior, as well as mood and behavior-dysregulation, revealed a significant reduction in the ADHD-Index and hyperactive components. Data from the open-label extension indicated sustained efficacy for children who continued to receive PS-Omega3. Children that switched to PS-Omega3 treatment from placebo showed a significant reduction in subscales scores of both CRS-P and the CRS-T, as compare to baseline scores. The treatment was well tolerated.

Conclusions

The results of this 30-week study suggest that PS-Omega3 may reduce ADHD symptoms in children. Preliminary analysis suggests that this treatment may be especially effective in a subgroup of hyperactive-impulsive, emotionally and behaviorally-dysregulated ADHD children.

Participation of the nucleus accumbens dopaminergic system in the antidepressant-like actions of a diet rich in omega-3 polyunsaturated fatty acids

The beneficial effects of omega (ω)-3 polyunsaturated fatty acid (PUFA) supplementation on major depressive disorder have been actively studied, but the underlying mechanism remains unknown. The present study examined the involvement of the nucleus accumbens (NAc) dopaminergic systems in behavioral changes in mice fed a diet high in ω-3 PUFAs. Mice fed a diet containing about double the amount of ω-3 PUFAs (krill oil (KO) diet) exerted shorter immobility times in the forced swim test (FST) than mice fed a control diet, containing only α-linolenic acid (ALA) as ω-3 PUFAs. The shorter immobility times were observed in both male and female mice. A dopamine metabolite, 3,4-dihydroxyphenylacetic acid, increased in the NAc in male mice fed the KO diet when compared with those fed the control diet. In addition, dopamine, 3-methoxytyramine, and homovanillic acid increased in the NAc in female mice fed the KO diet. Notably, the effects of the KO diet on the immobility time in the FST were abolished by microinjection of sulpiride, an antagonist of D₂-like receptors, into the NAc. A similar microinjection of an antagonist selective for D₁-like receptors, SKF83566, also abolished the reduction in immobility in the FST. Moreover, we found that tyrosine hydroxylase-positive cells increased in the ventral tegmental area (VTA) in mice fed the KO diet. These results suggest that modulation of the VTA-NAc dopaminergic pathway is one of the mechanisms by which a KO diet rich in ω-3 PUFAs reduces the immobility behavior in the mouse FST.

Co-treatment of vitamin D supplementation and aerobic training improves memory deficit in ovariectomized rat

Objective: Metabolic syndrome (MetS) and insufficient vitamin D levels are globally increasing phenomena which are correlated with cognitive impairment. This study investigated the interactive effect of aerobic training with vitamin D supplementation on memory deficit in rats with metabolic syndrome induced by ovariectomy.Methods: A total of forty Wistar rats weighing 240-255 gr were randomly matched on their body weight and divided into ovariectomy (OVX, n = 32) and sham-operated (SHAM; n = 8) groups. OV group was then divided into vitamin D supplementation (OVX + Vit D; 10000 IU/kg/week, for 8 weeks, n = 8), aerobic training (OVX + AT; n = 8), aerobic training and vitamin D supplementation (OVX + AT + Vit D; 10000 IU/kg/week, for 8 weeks, n = 8), and vehicle control group receiving sesame oil (OVX + Ses Oil; n = 8). After the end of intervention, passive avoidance learning and memory were assessed in step through passive avoidance paradigm. Obtained data were analyzed by ANOVA and post hoc Tukey test.Results: After 8 weeks of aerobic training and vitamin D supplementation, step through dark compartment latency (STL) was significantly higher and total time spent in that compartment (TSD) was lower in OVX + AT + Vit D compared to the other counterpart groups.Conclusion: Vitamin D supplementation combined with 8-week aerobic training alleviates cognitive impairment metabolic syndrome induced by ovariectomy.

Mechanisms of DHA-enriched phospholipids in improving cognitive deficits in aged SAMP8 mice with high-fat diet

Recent studies have shown that a high-fat diet (HFD) is involved in both metabolic dysfunction and cognitive deficiency and that docosahexaenoic-acid-enriched phospholipids (DHA-PLs) have beneficial effects on obesity and cognitive impairment. However, there are only a few studies comparing differences between DHA-PC and DHA-PS in HFD-induced Alzheimer's disease (AD) models. After 8 weeks feeding with HFD, 10-month-old SAMP8 mice were fed with 1% (w/w) DHA-PC or 1% DHA-PS (biosynthesized from DHA-PC) for 8 weeks; we then tested the behavioral performances in the Barnes maze test and Morris maze test. The changes of the generation and accumulation of Aβ, oxidative stress, apoptosis, neuroinflammation and neurotrophic factors were also measured. The results indicated that both DHA-PC and DHA-PS significantly improved the metabolic disorders and cognitive deficits. Both DHA-PC and DHA-PS could ameliorate oxidative stress, and DHA-PS presented more notable benefits than DHA-PC on Aβ pathology, mitochondrial damage, neuroinflammation and neurotrophic factors; DHA-PS was for the first time found to increase the production of insoluble Aβ (less pathogenic) in this AD model. These data suggest that DHA-PLs can significantly improve cognitive deficiency, and the molecular mechanisms for this closely relate to the phospholipid polar groups.

Glycerophospholipid Supplementation as a Potential Intervention for Supporting Cerebral Structure in Older Adults

Modifying nutritional intake through supplementation may be efficacious for altering the trajectory of cerebral structural decline evident with increasing age. To date, there have been a number of clinical trials in older adults whereby chronic supplementation with B vitamins, omega-3 fatty acids, or resveratrol, has been observed to either slow the rate of decline or repair cerebral tissue. There is also some evidence from animal studies indicating that supplementation with glycerophospholipids (GPL) may benefit cerebral structure, though these effects have not yet been investigated in adult humans. Despite this paucity of research, there are a number of factors predicting poorer cerebral structure in older humans, which GPL supplementation appears to beneficially modify or protect against. These include elevated concentrations of homocysteine, unbalanced activity of reactive oxygen species both increasing the risk of oxidative stress, increased concentrations of pro-inflammatory messengers, as well as poorer cardio- and cerebrovascular function. As such, it is hypothesized that GPL supplementation will support cerebral structure in older adults. These cerebral effects may influence cognitive function. The current review aims to provide a theoretical basis for future clinical trials investigating the effects of GPL supplementation on cerebral structural integrity in older adults.

Neuroprotective Effects of n-3 Polyunsaturated Fatty Acid-Enriched Phosphatidylserine Against Oxidative Damage in PC12 Cells

Neurodegenerative diseases are defined by progressive loss of specific neuronal cell populations and are associated with protein aggregates. Oxidative stress has been implicated in their pathological processes. Previous studies revealed that docosahexaenoic acid (DHA) is beneficial in neurodegenerative diseases. Phospholipids (PLs) derived from marine products are rich in DHA and eicosapentaenoic acid (EPA). In the present study, we investigated the neuroprotective effects of DHA-enriched and unenriched phosphatidylcholine (PC) and phosphatidylserine (PS) on oxidative stress induced by hydrogen peroxide (H₂O₂) and tert-butylhydroperoxide in PC12 cells. Cell viability and leakage of lactate dehydrogenase results showed that the neuroprotective effect of PS was superior to that of PC. DHA- and EPA-enriched PC and PS were superior to that without DHA or EPA; in addition, the improvement with n-3 polyunsaturated fatty acid-enriched PS (n-3 PS) was dose dependent. Acridine orange/ethidium bromide staining showed that DHA- and EPA-enriched PS (DHA/EPA-PS) could significantly inhibit apoptosis. Mechanistic studies revealed that EPA-PS and DHA-PS were effective to increase superoxide dismutase (SOD) levels by 48.4 and 58.2 % and total antioxidant capacity (T-AOC) level by 51 and 94 %, respectively, in the H₂O₂ model. Similar results for SOD and T-AOC levels were shown in the t-BHP model. EPA/DHA-PS could downregulate the messenger RNA level of Caspase-3, Caspase-9, and Bax, upregulate Bcl-2, inhibit Bax, and increase Bcl-2 at protein level. In conclusion, EPA/DHA-PS could protect PC12 cells from oxidative stress and prevent mitochondrial-mediated apoptosis. Our findings indicate that the neuroprotective effects of DHA/EPA-PLs depend on the molecular form. Further studies are necessary to reveal detailed mechanisms and structure-effect relationships.

Effect of vitamin D on the learning and memory ability of FGR rat and NMDA receptor expression in hippocampus

The aim of this study is to investigate the effect of vitamin D (VD) on the learning and memory ability of fetal growth restriction (FGR) rat and the expression of NMDA receptor in hippocampus. The FGR models of rat were established through passive smoking, and divided into two groups randomly, i.e. the control group and the observation group. Rats were fed regular diet with the addition of VD in the observation group. The serum level of 25(OH)-D₃ was assayed in both groups of the rats at different time points using ELISA, and the learning and memory ability of rat aged 30 days were evaluated using Morris water maze and passive avoidance test. In addition, we also compared the brain weight of rats at different age and detected the mRNA expression of NRI subunit of NMDA receptor of hippocampus of rats aged 30 days using quantitative RT-PCR. After 7 days, the serum level of 25(OH)D₃ in rats of the observation group was significantly higher than that of the control group (P<0.05); during the Morris water maze, we found no significant difference in comparison of the latency between the two groups in the first 2 days (P>0.05), but from the 3rd day, the latency of the observation group was shorter than that in the control group (P<0.05); in the passive avoidance test, no significant difference was identified when comparing the electric shock times between the two groups in the first 2 days, but from the 3rd day, the electric shock times in the observation group were significantly lower than those in the control group (P<0.05); the brain weight of rats in the observation group on the 1st, 7th and 14th day were all lower than those in the control group (P<0.05), but the comparison of brain weight at 21st and 30th day showed no significant difference (P>0.05) between the two groups. We also found that the mRNA and protein expression of NRI subunit of NMDA receptor in hippocampus was significantly higher in the observation group than in the control group (P<0.05). VD can increase the learning and memory ability of FGR rats, significantly ameliorating the cognitive dysfunction of FGR rat and improving the learning and memory ability of rats, which may be related to the upregulation of NRI subunit of NMDA receptor.

Human Neural Stem Cell Aging Is Counteracted by α-Glycerylphosphorylethanolamine

Neural stem cells (NSCs) represent a subpopulation of cells, located in specific regions of the adult mammalian brain, with the ability of self-renewing and generating neurons and glia. In aged NSCs, modifications in the amount and composition of membrane proteins/lipids, which lead to a reduction in membrane fluidity and cholinergic activities, have been reported. In this respect, molecules that are effective at normalizing the membrane composition and cholinergic signaling could counteract stem cell aging. α-Glycerylphosphorylethanolamine (GPE), a nootropic drug, plays a role in phospholipid biosynthesis and acetylcholine release. Herein, GPE was assayed on human NSC cultures and on hydroxyurea-aged cells. Using cell counting, colorimetric, and fluorimetric analyses, immunoenzymatic assays, and real time PCR experiments, NSC culture proliferation, senescence, reactive oxygen species, and ADP/ATP levels were assessed. Aged NSCs exhibited cellular senescence, decreased proliferation, and an impairment in mitochondrial metabolism. These changes included a substantial induction in the nuclear factor NF-κB, a key inflammatory mediator. GPE cell treatment significantly protected the redox state and functional integrity of mitochondria, and counteracted senescence and NF-κB activation. In conclusion, our data show the beneficial properties of GPE in this model of stem cell aging.

Comparative Study of EPA-enriched Phosphatidylcholine and EPA-enriched Phosphatidylserine on Lipid Metabolism in Mice

Recent studies have shown that EPA enriched PLs have beneficial effects on lipid metabolism. Our previous study has demonstrated that the anti-obesity and hypolipidemic effects of EPA-PL were superior to DHA-PL. In the present study, we comparatively evaluated the effects of EPA-enriched phosphatidylcholine (EPA-PC) and EPA-enriched phosphatidylserine (EPA-PS) on lipid metabolism in mice. Both 2% dietary EPA-PC and EPA-PS significantly improved serum and hepatic lipid levels in mice. The HDL-c level in mice on EPA-PC diet was significantly higher than the other two groups. The level of DHA in hepatic TG and PL were significantly increased in both EPA-PC and EPA-PS fed groups (98.3 and 117.8%, respectively; p < 0.05). Notably, the proportion of DHA in EPA-PS group was significantly higher than the EPA-PC group. EPA-PC and EPA-PS suppressed hepatic SREBP-1c mediated lipogenesis and activated PPARα mediated fatty acid β-oxidation in the liver. These data are the first to indicate that EPA-PS has beneficial effects on lipid metabolism.

Mente Activa® Improves Impaired Spatial Memory in Aging Rats

OBJECTIVES

Aging is accompanied by a decline in several aspects of the cognitive function, having negative personal and socioeconomic impacts. Dietary supplements could be beneficial for preventing age-related cognitive decline. In this context, we examined whether the nutritional supplement Mente Activa® has beneficial effects on aging-related cognitive deficits without inducing side effects.

METHODS

Mente Activa® was administered to old rats (n= 30 treated rats and n= 30 control rats) during 5 months, and the Morris water maze was used to test the learning capacities of the animals. The first assessment was conducted before the nutritional intervention (age of 18-19 months), to determine the baseline of the performance of animals on this test, and the second assessment was performed at the end of the treatment (23-24 moths). In order to examine possible secondary effects of this nutritional supplement, plasma, heart anatomy and liver parameters were evaluated.

RESULTS

Our data indicate that supplemented rats showed less escape latency, distance swum, higher use of spatial search strategies, and crossed the former platform location with higher frequency than control rats. These effects were specific of the treatment, indicating that this nutritional supplement has a beneficial effect on spatial memory. On the other hand, the regular intake of Mente Activa® did not induce any negative effects in plasma parameters and heart size.

CONCLUSIONS

Aged rats under a sustained dietary intake of the nutritional supplement Mente Activa® displayed improved learning and memory abilities compared to the non-treated rats. These results suggest the therapeutic potential and safety of use of Mente Activa® for age-related cognitive deficits, particularly, in the onset of the first cognitive dysfunction symptoms.

Oral administration of squid lecithin-transphosphatidylated phosphatidylserine improves memory impairment in aged rats

Recently, lecithin-derived phosphatidylserine (PS), which originates from marine life, has received much attention as a viable alternative to bovine cerebral cortex PS. In this study, the use of squid phosphatidylcholine-transphosphatidylated PS (SQ-PS) was evaluated through examination of its ameliorating effects on age-associated learning and memory deficits in rats. Aged rats were orally administered SQ-PS (10, 20, or 50 mg/kg per day) once a day for seven days 30 min prior to behavioral assessment in a Morris water maze. SQ-PS administration produced significant dose-dependent improvements in escape latency for finding the platform in the Morris water maze in the aged rats even though Soy-PS administration also exhibited comparable improvements with SQ-PS. Biochemical alterations in the hippocampal cholinergic system, including changes in choline acetyltransferase and acetylcholinesterase immunoreactivity, were consistent with the behavioral results. In addition, SQ-PS treatment significantly restored age-associated decreases of choline transporter and muscarinic acetylcholine receptor type 1 mRNA expression in the hippocampus. These results demonstrate that orally administered SQ-PS dose-dependently aids in the improvement of memory deficits that occur during normal aging in rats. This suggests that SQ-PS may be a useful therapeutic agent in the treatment of diminished memory function in elderly people.

Positive effects of soy lecithin-derived phosphatidylserine plus phosphatidic acid on memory, cognition, daily functioning, and mood in elderly patients with Alzheimer's disease and dementia

INTRODUCTION

We report previously unpublished, early pilot studies performed with a brain-health food supplement containing a proprietary blend of 100 mg phosphatidylserine (PS) and 80 mg phosphatidic acid (PA) produced from soy lecithin.

METHODS

Serum analysis after single PS+PA ingestion was performed in healthy volunteers. A 3-month double-blind, placebo-controlled study assessed the influence of three PS+PA capsules/day, (300 mg PS + 240 mg PA/day) or placebo on memory and mood in functioning, non-depressive elderly people with memory problems, using the Wechsler Memory Scale and the List of Depressive Symptoms. Furthermore, a 2-month randomized, double-blind, placebo-controlled trial assessed the effect of three PS+PA capsules/day (300 mg PS + 240 mg PA/day) or placebo on daily functioning, mental health, emotional state, and self-reported general condition in patients with Alzheimer's disease (AD).

RESULTS

Serum PS peaked 90 min after ingestion, returning to baseline after 180 min. In the elderly, PS+PA [per protocol (PP) n = 31], unlike placebo (PP n = 26), significantly improved memory and prevented "winter blues" in a pre-post comparison. In the patients with AD, daily functioning (i.e., 7 activities of daily living) under PS+PA (PP n = 53) remained unchanged, but declined from 5.62 to 4.90 under placebo (PP n = 39; P = 0.035), with significant group difference (P = 0.021). The PS+PA group had 3.8% deterioration and 90.6% stability in daily functioning, compared to 17.9% and 79.5% under placebo, respectively (P = 0.066). Forty-nine percent of the PS+PA patients reported an improved general condition, compared to 26.3% under placebo (P = 0.084). Approximately, 43% of the PS+PA patients, but none under placebo, continued post-trial supplementation (while double-blinded). No negative side effects were observed.

CONCLUSION

PS is efficiently absorbed after oral consumption. A positive influence of PS+PA on memory, mood, and cognition was demonstrated among elderly test subjects. Short-term supplementation with PS+PA in patients with AD showed a stabilizing effect on daily functioning, emotional state and self-reported general condition. The data encourage long-term studies with PS+PA in AD patients and other elderly with memory or cognition problems.

Acupuncture stimulation improves scopolamine-induced cognitive impairment via activation of cholinergic system and regulation of BDNF and CREB expressions in rats

Background

Acupuncture is an alternative therapy that is widely used to treat various neurodegenerative diseases and effectively improve cognitive and memory impairment. The aim of this study was to examine whether acupuncture stimulation at the Baihui (GV20) acupoint improves memory defects caused by scopolamine (SCO) administration in rats. We also investigated the effects of acupuncture stimulation at GV20 on the cholinergic system as well as the expression of brain-derived neurotrophic factor (BDNF) and cAMP-response element-binding protein (CREB) in the hippocampus.

Methods

SCO (2 mg/kg, i.p.) was administered to male rats once daily for 14 days. Acupuncture stimulation at GV20 was performed for 5 min before SCO injection. After inducing cognitive impairment via SCO administration, we conducted a passive avoidance test (PAT) and the Morris water maze (MWM) test to assess behavior.

Results

Acupuncture stimulation at GV20 improved memory impairment as measured by the PAT and reduced the escape latency for finding the platform in the MWM test. Acupuncture stimulation at GV20 significantly alleviated memory-associated decreases in the levels of choline acetyltransferase (ChAT), BDNF and CREB proteins in the hippocampus. Additionally, acupuncture stimulation at GV20 significantly restored the expression of choline transporter 1 (CHT1), vesicular acetylcholine transporter (VAChT), BDNF and CREB mRNA in the hippocampus. These results demonstrate that acupuncture stimulation at GV20 exerts significant neuroprotective effects against SCO-induced neuronal impairment and memory dysfunction in rats.

Conclusions

These findings suggest that acupuncture stimulation at GV20 might be useful in various neurodegenerative diseases to improve cognitive functioning via stimulating cholinergic enzyme activities and regulating BDNF and CREB expression in the brain.

Phosphatidylserine in the brain: metabolism and function

Phosphatidylserine (PS) is the major anionic phospholipid class particularly enriched in the inner leaflet of the plasma membrane in neural tissues. PS is synthesized from phosphatidylcholine or phosphatidylethanolamine by exchanging the base head group with serine, and this reaction is catalyzed by phosphatidylserine synthase 1 and phosphatidylserine synthase 2 located in the endoplasmic reticulum. Activation of Akt, Raf-1 and protein kinase C signaling, which supports neuronal survival and differentiation, requires interaction of these proteins with PS localized in the cytoplasmic leaflet of the plasma membrane. Furthermore, neurotransmitter release by exocytosis and a number of synaptic receptors and proteins are modulated by PS present in the neuronal membranes. Brain is highly enriched with docosahexaenoic acid (DHA), and brain PS has a high DHA content. By promoting PS synthesis, DHA can uniquely expand the PS pool in neuronal membranes and thereby influence PS-dependent signaling and protein function. Ethanol decreases DHA-promoted PS synthesis and accumulation in neurons, which may contribute to the deleterious effects of ethanol intake. Improvement of some memory functions has been observed in cognitively impaired subjects as a result of PS supplementation, but the mechanism is unclear.

Neuroprotective properties of the marine carotenoid astaxanthin and omega-3 fatty acids, and perspectives for the natural combination of both in krill oil

The consumption of marine fishes and general seafood has long been recommended by several medical authorities as a long-term nutritional intervention to preserve mental health, hinder neurodegenerative processes, and sustain cognitive capacities in humans. Most of the neurological benefits provided by frequent seafood consumption comes from adequate uptake of omega-3 and omega-6 polyunsaturated fatty acids, n-3/n-6 PUFAs, and antioxidants. Optimal n-3/n-6 PUFAs ratios allow efficient inflammatory responses that prevent the initiation and progression of many neurological disorders. Moreover, interesting in vivo and clinical studies with the marine antioxidant carotenoid astaxanthin (present in salmon, shrimp, and lobster) have shown promising results against free radical-promoted neurodegenerative processes and cognition loss. This review presents the state-of-the-art applications of n-3/n-6 PUFAs and astaxanthin as nutraceuticals against neurodegenerative diseases associated with exacerbated oxidative stress in CNS. The fundamental “neurohormesis” principle is discussed throughout this paper. Finally, new perspectives for the application of a natural combination of the aforementioned anti-inflammatory and antioxidant agents (found in krill oil) are also presented herewith.

Supplementation of complex milk lipid concentrate (CMLc) improved the memory of aged rats

OBJECTIVES

The socio-economic impact from age-related mental decline is escalating. Supplementation of functional foods for sustaining mental health is desirable. We examined the effect of long-term supplementation of complex milk lipid concentrate (CMLc), mixed dairy phospholipids, on memory and associated vascular and neuronal changes in aged rats.

METHODS

Fisher/Norway Brown rats were used. Two groups of aged rats (24 months) were fed with either gelatin-formulated CMLc or blank gelatin as the control, for 4 months. To determine age-related changes, a young group (5 months) was also fed with blank gelatin. Morris water maze tests were carried out after the supplementation and brain tissues were collected for biological analysis.

RESULTS

The aged control rats learnt to locate the platform slower than the young control rats during acquisition trials (*P < 0.05), and made fewer entries to and more initial heading errors from the platform zone during testing trials (*P < 0.05). The CMLc supplementation improved memory by showing the reduced initial heading errors in a delayed probe trial ((#)P < 0.05). We also found that the aged rats with CMLc supplementation improved vascular density, dopamine output, and neuroplasticity ((#)P < 0.05) in the brain regions involved in memory compared with that of the aged control rats.

DISCUSSION

The data suggested that the supplementation of CMLc during the early stage of brain aging may prevent memory decline possibly through improving vascular and neuronal function.

Krill-Derived Phosphatidylserine Improves TMT-Induced Memory Impairment in the Rat

The present study examined the effects of krill-derived phosphatidylserine (Krill-PS) on the learning and memory function and the neural activity in rats with trimethyltin (TMT)-induced memory deficits. The rats were administered vehicle (medium-chain triglyceride: MCT) or Krill-PS (50, 100 mg/kg, p.o.) daily for 21 days. The cognitive improving efficacy of Krill-PS in TMT-induced amnesic rats was investigated by assessing the Morris water maze test and by performing choline acetyltransferase (ChAT), acetylcholinesterase (AChE) and cAMP responsive element binding protein (CREB) immunohistochemistry. The rats with TMT injection showed impaired learning and memory of the tasks and treatment with Krill-PS produced a significant improvement of the escape latency to find the platform in the Morris water maze at the 2^nd and 4^th day compared to that of the MCT group (p<0.05). In the retention test, the Krill-PS+MCT groups showed increased time spent around the platform compared to that of the MCT group. Consistent with the behavioral data, Krill-PS 50+MCT group significantly alleviated the loss of acetylcholinergic neurons in the hippocampus and medial septum compared to that of the MCT group. Treatment with Krill-PS significantly increased the CREB positive neurons in the hippocampal CA1 area as compared to that of the MCT group. These results suggest that Krill-PS may be useful for improving the cognitive function via regulation of cholinergic marker enzyme activity and neural activity.

Marine omega-3 phospholipids: metabolism and biological activities

The biological activities of omega-3 fatty acids (n-3 FAs) have been under extensive study for several decades. However, not much attention has been paid to differences of dietary forms, such as triglycerides (TGs) versus ethyl esters or phospholipids (PLs). New innovative marine raw materials, like krill and fish by-products, present n-3 FAs mainly in the PL form. With their increasing availability, new evidence has emerged on n-3 PL biological activities and differences to n-3 TGs. In this review, we describe the recently discovered nutritional properties of n-3 PLs on different parameters of metabolic syndrome and highlight their different metabolic bioavailability in comparison to other dietary forms of n-3 FAs.

Formulation and shelf life stability of water-borne lecithin nanoparticles for potential application in dietary supplements field

ABSTRACT The objective of the present investigation is to formulate commercial soybean lecithin as nanoparticles in solvent-free aqueous system for potential supplementary applications. A mechanical method, which involved two major steps, was used for that purpose. First, lecithin submicron particles (~ 0.5 μm) have been prepared by gradual hydration of lecithin powder using mechanical agitation. Finally, the size of these particles was further reduced to < 100 nm by using high-pressure microfluidization. The physical stability (appearance, particle size distribution, ζ-potential) and the chemical stability (lipid oxidation) of the dispersions carrying lecithin nanoparticles were assessed every 15 days during the 3-month shelf life period at two different temperatures. Results showed that the final particle size of lecithin in the freshly prepared aqueous dispersion was 79.8 ± 1.0 nm and the amount of peroxide detected was 3.5 ± 0.2 meq/kg lipid. At the end of the storage period, dispersions stored at 4°C exhibited physical and chemical stability as evident from the translucent appearance, the small change in particle size (84.1 ± 1.3 nm), and the small amount of generated peroxides (4.1 ± 0.2 meq/kg lipid). On the other hand, dispersions stored at 25°C were physically stable up to 60 days. Over that period, samples became turbid and the particle size increased to 145.0 ± 1.7 nm with a bimodal distribution pattern. This behavior was due to phospholipids (PLs) degradation and hydrolysis under acidic conditions, which proceeds faster at a relatively high temperature (25°C) than at (4°C). The outcome of this investigation may help in developing water-based dispersions carrying lecithin nanoparticles for dietary supplement of PLs.

Chronic Treatment with Squid Phosphatidylserine Activates Glucose Uptake and Ameliorates TMT-Induced Cognitive Deficit in Rats via Activation of Cholinergic Systems

The present study examined the effects of squid phosphatidylserine (Squid-PS) on the learning and memory function and the neural activity in rats with TMT-induced memory deficits. The rats were administered saline or squid derived Squid-PS (Squid-PS 50 mg kg(-1), p.o.) daily for 21 days. The cognitive improving efficacy of Squid-PS on the amnesic rats, which was induced by TMT, was investigated by assessing the passive avoidance task and by performing choline acetyltransferase (ChAT) and acetylcholinesterase (AchE) immunohistochemistry. 18F-Fluorodeoxyglucose and performed a positron emission tomography (PET) scan was also performed. In the passive avoidance test, the control group which were injected with TMT showed a markedly lower latency time than the non-treated normal group (P < 0.05). However, treatment of Squid-PS significantly recovered the impairment of memory compared to the control group (P < 0.05). Consistent with the behavioral data, Squid-PS significantly alleviated the loss of ChAT immunoreactive neurons in the hippocampal CA3 compared to that of the control group (P < 0.01). Also, Squid-PS significantly increased the AchE positive neurons in the hippocampal CA1 and CA3. In the PET analysis, Squid-PS treatment increased the glucose uptake more than twofold in the frontal lobe and the hippocampus (P < 0.05, resp.). These results suggest that Squid-PS may be useful for improving the cognitive function via regulation of cholinergic enzyme activity and neural activity.

Autophagy is involved in traumatic brain injury-induced cell death and contributes to functional outcome deficits in mice

Previous data demonstrate that traumatic brain injury (TBI) activates autophagy, and increases microtubule-associated protein 1 light chain 3 (LC3) immunostaining mainly in neurons. However, the role of autophagy in traumatic brain damage remains elusive. The aim of the present study was to investigate the autophagic mechanisms participating in traumatic brain injury. The autophagy inhibitors 3-methyladenine (3-MA) and bafliomycin A1 (BFA) were administered with a single i.c.v. injection before TBI. We first examined the protein levels of Beclin-1 and LC3 II, which have been found to promote autophagy previously. Immunoblotting analysis showed that 3-MA pretreatment reduced post-TBI Beclin-1 and LC3-II levels, and maintained p62/SQSTM1 (p62) levels. In addition, double immunolabeling showed that the increased punctate LC3-II dots colocalizing with Propidium Iodide (PI)-stained nuclei at 24 h after injury, were partially inhibited by 3-MA pretreatment. Furthermore, inhibition of autophagy could reduce TBI-induced cell injury assessed with i.p. injection of PI and lesion volume, and attenuate behavioral outcome evaluated by motor test and Morris water maze. The neuroprotective effects were associated with an inhibition on TBI-induced up-regulation of LC3, Beclin-1, cathepsin B, caspase-3 and the Beclin-1/Bcl-2 ratio. Taken together, these data imply that the autophagy pathway is involved in the pathophysiologic responses after TBI, and inhibition of this pathway may help attenuate traumatic damage and functional outcome deficits.