Omega-3 fatty acids and dementia

Plasma fatty acids and attention deficit hyperactivity disorder: a Mendelian randomization investigation

Background

Attention deficit hyperactivity disorder (ADHD) is the most common neurodevelopmental disorder of childhood, and pathogenesis is not fully understood. Observational studies suggest an association between fatty acids abnormalities and ADHD, but there are contradictions and differences between these findings. To address this uncertainty, we employed a two-sample bidirectional Mendelian Randomization (MR) analysis to investigate the causal relationship between fatty acids and ADHD.

Methods

We conducted a two-sample Mendelian Randomization (MR) study, selecting single nucleotide polymorphisms (SNPs) highly correlated with fatty acid levels from the CHARGE Consortium as our instruments. The outcome data were sourced from the Psychiatric Genomics Consortium (PGC) dataset on ADHD, comprising 225,534 individuals, with 162,384 cases and 65,693 controls. Inverse variance weighting, MR-Egger, and weighted median methods were employed to estimate the causal relationship between fatty acids and ADHD. Cochran's Q-test was used to quantify heterogeneity of instrumental variables. Sensitivity analyses included MR-Egger intercept tests, leave-one-out analyses, and funnel plots.

Results

The MR analysis revealed no significant associations between genetically predicted levels of various saturated, monounsaturated, and polyunsaturated fatty acids (including omega-3 and omega-6) and ADHD risk in the CHARGE and PGC cohorts. Notably, an initial association with Dihomo-gamma-linolenic acid (DGLA) (OR = 1.009, p = 0.032 by IVW) did not persist after correction for multiple testing (adjusted p-value = 0.286). Sensitivity analysis supported our findings, indicating robustness. Moreover, there was a lack of evidence supporting a causal link from ADHD to fatty acids.

Conclusion

While our study on the basis of genetic data does not provide evidence to support the causal role of fatty acids in ADHD, it does not preclude their potential involvement in reducing the risk of ADHD. Further research is needed to explore this possibility.

Unraveling the therapeutic efficacy of resveratrol in Alzheimer's disease: an umbrella review of systematic evidence

CONTEXT

Resveratrol (RV), a natural compound found in grapes, berries, and peanuts, has been extensively studied for its potential in treating Alzheimer's disease (AD). RV has shown promise in inhibiting the formation of beta-amyloid plaques (Aβ) and neurofibrillary tangles (NFTs), protecting against neuronal damage and oxidative stress, reducing inflammation, promoting neuroprotection, and improving the function of the blood-brain barrier (BBB). However, conflicting results have been reported, necessitating a comprehensive umbrella review of systematic reviews to provide an unbiased conclusion on the therapeutic effectiveness of RV in AD.

OBJECTIVE

The objective of this study was to systematically synthesize and evaluate systematic and meta-analysis reviews investigating the role of RV in AD using data from both human and animal studies.

DATA SOURCES AND EXTRACTION

Of the 34 systematic and meta-analysis reviews examining the association between RV and AD that were collected, six were included in this study based on specific selection criteria. To identify pertinent studies, a comprehensive search was conducted in English-language peer-reviewed journals without any restrictions on the publication date until October 15, 2023. The search was carried out across multiple databases, including Embase, MEDLINE (PubMed), Cochrane Library, Web of Science, and Google Scholar, utilizing appropriate terms relevant to the specific research field. The AMSTAR-2 and ROBIS tools were also used to evaluate the quality and risk of bias of the included systematic reviews, respectively. Two researchers independently extracted and analyzed the data, resolving any discrepancies through consensus. Of note, the study adhered to the PRIOR checklist.

DATA ANALYSIS

This umbrella review presented robust evidence supporting the positive impacts of RV in AD, irrespective of the specific mechanisms involved. It indeed indicated that all six systematic and meta-analysis reviews unanimously concluded that the consumption of RV can be effective in the treatment of AD.

CONCLUSION

RV exhibits promising potential for benefiting individuals with AD through various mechanisms. It has been observed to enhance cognitive function, reduce Aβ accumulation, provide neuroprotection, protect the BBB, support mitochondrial function, facilitate synaptic plasticity, stabilize tau proteins, mitigate oxidative stress, and reduce neuroinflammation commonly associated with AD.

Fish oil supplementation and risk of dementia among diabetic patients: a prospective study of 16,061 older patients

BACKGROUND

Although n-3 Polyunsaturated fatty acids (PUFAs) may benefit cognitive performance, the association of n-3 PUFA intake with dementia risk under dysglycemia has not been examined. We aimed to evaluate the relationship between fish oil supplement use or fish consumption and dementia risk among older patients with diabetes.

METHOD

A total of 16,061 diabetic patients aged over 60 years were followed up in the UK Biobank. Fish oil supplements use (yes or no) was collected by the touch screen questionnaire. The diagnosis of dementia was ascertained by the UK Biobank Outcome Adjudication Group. The hazard ratios (HRs) and 95% confidence intervals (95% CIs) were estimated using Cox proportional hazards models.

RESULTS

A total of 337 cases of dementia were confirmed after a mean duration of 7.7 years (123,486 person-years) of follow-up. Habitual use of fish oil supplements showed a 24% lower dementia risk among older diabetic patients [HRs (95% CIs): 0.76 (0.60-0.98) (P = 0.031)] compared with non-users. Such inverse association was not modified by the APOE ε4 genotype. However, the consumption of both oily fish (≥2 times/week) and non-oily fish (≥2 times/week) had no significant association with dementia risk (p-trend = 0.271 and p-trend = 0.065) compared with non-consumers.

CONCLUSION

In summary, fish oil supplementation may play a protective role in cognitive function across all APOE genotypes, while non-oily fish and oily fish consumption have no protective association among older diabetic patients.

Using Focus Groups to Explore Older Black Men's Perception of Dietary Interventions

Older Black men are underrepresented in research despite being disproportionately affected by Alzheimer's disease (AD) and cardiovascular (CV) risk factors related to AD compared with non-Hispanic Whites. Although dietary interventions have shown promise to reduce modifiable CV risk factors related to AD, Black Americans have lower adherence likely due to lack of cultural considerations. Using a noninterventional convergent parallel mixed-methods approach, this study examined the cultural contexts that inform perceptions of dietary interventions among older Midwestern Black men. All participants completed an online demographic and dietary habit survey prior to focus group discussions. Two focus group discussion sessions were conducted with a total of 10 cognitively normal Black men aged 55 years and older. Survey data were analyzed using a frequency analysis and qualitative data were analyzed using a six-step thematic analysis process. Most men indicated having hypertension (N = 7, 77.8%) and currently not following a dietary eating pattern (N = 8, 88.9%). Emerging themes identified included (1) knowledge of dementia, (2) perceptions of dietary interventions, (3) barriers impacting participation in dietary interventions, and (4) overcoming barriers to engage Black men in dietary interventions. Findings from this study should inform the design of future dietary interventions for AD prevention to enhance participation among older Black men.

Dietary inflammatory index and neuropsychiatric disorders

Neuropsychiatric disorders (NPDs) are considered a potential threat to mental health. Inflammation predominantly plays a role in the pathophysiology of NPDs. Dietary patterns are widely postulated to be involved in the physiological response to inflammation. This review aims to discuss the literature on how dietary inflammatory index (DII) is related to inflammation and, consequently, NPDs. After comprehensive scrutiny in different databases, the articles that investigated the relation of DII score and various NPDs and psychological circumstances were included. The association between dietary patterns and mental disorders comprising depression, anxiety, and stress proved the role of a proinflammatory diet in these conditions' exacerbation. Aging is another condition closely associated with DII. The impact of proinflammatory and anti-inflammatory diet on sleep quality indicated related disorders like sleep latency and day dysfunctions among the different populations are in relation with the high DII score. The potential effects of genetic backgrounds, dietary patterns, and the gut microbiome on DII are discussed as well. To plan preventive or therapeutic interventions considering the DII, these factors, especially genetic variations, should be considered as there is a growing body of literature indicating the role of personalized medicine in different NPDs. To the best of our knowledge, there is a limited number of RCTs on this subject, so future research should evaluate the causality via RCTs and look for therapeutic interventions with an eye on personalized medicine using information about DII in NPDs.

Unlocking the Molecular Variations of a Micron-Scale Amyloid Plaque in an Early Stage Alzheimer's Disease by a Cellular-Resolution Mass Spectrometry Imaging Platform

Uncovering the molecular changes at the site where Aβ is deposited plays a critical role in advancing the diagnosis and treatment of Alzheimer's disease. However, there is currently a lack of a suitable label-free imaging method with a high spatial resolution for brain tissue analysis. In this study, we propose a modified desorption electrospray ionization (DESI) mass spectrometry imaging (MSI) method, called segmented temperature-controlled DESI (STC-DESI), to achieve high-resolution and high-sensitivity spatial metabolomics observation by precisely controlling desorption and ionization temperatures. By concentrating the spray plume and accelerating solvent evaporation at different temperatures, we achieved an impressive spatial resolution of 20 μm that enables direct observation of the heterogeneity around a single cell or an individual Aβ plaque and an exciting sensitivity that allows a variety of low-abundance metabolites and less ionizable neutral lipids to be detected. We applied this STC-DESI method to analyze the brains of transgenic AD mice and identified molecular changes associated with individual Aβ aggregates. More importantly, our study provides the first evidence that carnosine is significantly depleted and 5-caffeoylquinic acid (5-CQA) levels rise sharply around Aβ deposits. These observations highlight the potential of carnosine as a sensitive molecular probe for clinical magnetic resonance imaging diagnosis and the potential of 5-CQA as an efficient therapeutic strategy for Aβ clearance in the early AD stage. Overall, our findings demonstrate the effectiveness of our STC-DESI method and shed light on the potential roles of these molecules in AD pathology, specifically in cellular endocytosis, gray matter network disruption, and paravascular Aβ clearance.

Behavior and Cognition of the Senior Cat and Its Interaction with Physical Disease

In cats, age-related pathologic condition and neurologic degeneration can produce changes in activity, vocalization, appearance, appetite, litter box use, sleep-wake cycle, personality, and cognitive ability. These changes can influence the relationship between owner and pet. Although cognitive dysfunction syndrome (CDS) can cause altered behavior later in life, other medical or behavioral causes may mimic these clinical signs or complicate diagnosis. Management and treatment of CDS can be accomplished through pharmacologic intervention, diet and nutritional supplementation, and environmental enrichment aimed at slowing the progression of the disease.

Circulating metabolites and risk of incident dementia: A prospective cohort study

Identifying circulating metabolites associated with dementia, cognition, and brain volume may improve the understanding of dementia pathogenesis and provide novel insights for preventive and therapeutic interventions. This cohort study included a total of 87 885 participants (median follow-up of 9.1 years, 54% female) without dementia at baseline from the UK Biobank. A total of 249 plasma metabolites were measured using nuclear magnetic resonance spectroscopy at baseline. Cox proportional regression was used to examine the associations of each metabolite with incident dementia (cases = 1134), Alzheimer's disease (AD; cases = 488), and vascular dementia (VD; cases = 257) during follow-up. Dementia-associated metabolites were further analyzed for association with cognitive deficits (N = 87 885) and brain volume (N = 7756) using logistic regression and linear regression. We identified 26 metabolites associated with incident dementia, of which 6 were associated with incident AD and 5 were associated with incident VD. These 26 dementia-related metabolites were subfractions of intermediate-density lipoprotein, large low-density lipoprotein (L-LDL), small high-density lipoprotein (S-HDL), very-low-density lipoprotein, fatty acids, ketone bodies, citrate, glucose, and valine. Among them, the cholesterol percentage in L-LDL (L-LDL-C%) was associated with lower risk of AD (HR [95% CI] = 0.92 [0.87-0.97], p = 0.002), higher brain cortical (β = 0.047, p = 3.91 × 10-6 ), and hippocampal (β = 0.043, p = 1.93 × 10-4 ) volume. Cholesteryl ester-to-total lipid ratio in L-LDL (L-LDL-CE%) was associated with lower risk of AD (HR [95% CI] = 0.93 [0.90-0.96], p = 1.48 × 10-4 ), cognitive deficits (odds ratio = 0.98, p = 0.009), and higher hippocampal volume (β = 0.027, p = 0.009). Cholesteryl esters in S-HDL (S-HDL-CE) were associated with lower risk of VD (HR [95% CI] = 0.81 [0.71-0.93], p = 0.002), but not AD. Taken together, circulating levels of L-LDL-CE% and L-LDL-C% were robustly associated with risk of AD and AD phenotypes, but not with VD. S-HDL-CE was associated with lower risk of VD, but not with AD or AD phenotypes. These metabolites may play a role in the advancement of future intervention trials. Additional research is necessary to gain a complete comprehension of the molecular mechanisms behind these associations.

Investigating Owner Use of Dietary Supplements in Dogs with Canine Cognitive Dysfunction

Canine cognitive dysfunction (CCD) is becoming increasingly recognized in veterinary medicine, as dogs live longer and with CCD being highly prevalent among the elderly dog population. Various studies have shown that diet and dietary supplementation can positively influence the clinical signs of CCD, especially if given at an early stage. The aim of this study was to investigate owner use of dietary supplements (DSs) in dogs with age-related behavioral changes. An observational study based on an online questionnaire for owners of dogs with age-related behavioral changes was performed. Out of a total of 394 owners who completed the survey, after noticing age-related behavioral changes, over half of the dogs received DSs (54%), whereas only 8% reported changing their dog's base diet. The most used DS was fish oil (48%). The use of DSs should be discussed with and monitored by veterinary surgeons since many geriatric patients have multi-morbidities, may have specific nutritional requirements and receive multi-faceted medications.

Effectiveness of Fish Roe, Snow Fungus, and Yeast Supplementation for Cognitive Function: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

The brain is one of the most critical organs in the human body, regulating functions such as thinking, memory, learning, and perception. Studies have indicated that fish roe, snow fungus, and yeast may have the potential to modulate cognitive, memory, and emotional functions. However, more relevant clinical research in this area still needs to be conducted. This study explored the cognition-enhancing potential of a formula beverage including fish roe, snow fungus, and yeast. Sixty-four subjects were divided into a placebo group (n = 32) and a formula-drink group (n = 32), who consumed the product for 8 weeks. Cognitive tests were administered and analyzed at weeks 0, 4, and 8. After 4 and 8 weeks, there was a significant increase in the number of memory cards, and the response times among those who consumed the formula beverage were significantly faster than those in the placebo group. The subjects remembered the old items better and were more impressed with similar items based on the week effect. There was a significant increase in the cue effect of happy facial expressions after the subjects consumed the formula beverage for 8 weeks. In addition, there was a significant decrease in anxiety and fatigue, and improved quality of life. This formula beverage is a promising option that could be used to prevent further cognitive decline in adults with subjective cognitive complaints.

Effects of Polyunsaturated Fatty Acid Serum Levels on Vascular Dementia: A Two-Sample Mendelian Randomization Study

INTRODUCTION

Several observational studies have indicated that polyunsaturated fatty acid serum levels (PUFAs) are associated with vascular dementia (VaD), but their causal relationships remain elusive. Therefore, we attempted to evaluate the causal effect of PUFAs on VaD in a two-sample Mendelian randomization (MR) analysis by using summary statistics from aggregated genome-wide association studies.

METHODS

The inverse-variance weighted (IVW) method was performed as the primary analysis. Sensitivity analyses (MR-Egger regression, weighted median, penalized weighted median, and MR pleiotropy residual sum and outlier methods) were also implemented to estimate the effects of potential violations of MR hypotheses.

RESULTS

No causality was found for PUFAs (odds ratio, 1.14; 95% confidence interval, 0.91-1.42; p = 0.25) on VaD in the IVW model. The results were consistent in sensitivity analyses. There was no notable horizontal pleiotropy or heterogeneity.

CONCLUSION

In this two-sample MR analysis, our findings did not support the assumption that PUFAs play causal role in the occurrence or development of VaD.

Potentiality Assessment of the Acetylcholinesterase-Inhibitory Activity of Olive Oil with an Additive Edible Insect Powder

Edible insects (Alphitobius diaperinus Panzer, Gryllus campestris, Tenebrio molitor, Chorthippus biguttulus) are rich in nutrients that potentially inhibit acetylcholinesterase (AChE), but also improve cognition. The aim of this study was to evaluate four varied species of freeze-dried edible insects (purchased from a store); their nutrient composition, including fat, total phenolic compounds, vitamins, and antioxidant properties; and the potential inhibitory effect of AChE. An additional goal was to obtain olive oil with the addition of edible insects. Such oil was characterized by high oxidizing properties and showed high affinity to AChE. The results showed that mealworms and grasshoppers had the highest content of fats (PUFA/SFA) and phenolic compounds. These insects also showed a high content of vitamins, which correlated with the highest affinity for AChE. Therefore, they were added as a functional additive to olive oil. Olive oil with the addition of edible insects showed a higher affinity for AChE and enriched the olive oil with vitamin C and B vitamins.

Promising Effects of N-Docosahexaenoyl Ethanolamine in Breast Cancer: Molecular and Cellular Insights

Unhealthy dietary habits have been identified as a risk factor for the development and progression of cancer. Therefore, adopting a healthy eating pattern is currently recommended to prevent the onset of different types of cancers, including breast carcinoma. In particular, the Mediterranean diet, based on high consumption of omega-3 polyunsaturated fatty acids (N-3 PUFAs), such as those found in cold-water fish and other seafood, nuts, and seeds, is recommended to reduce the incidence of several chronic-degenerative diseases. Indeed, the consumption of N-3 PUFAs, particularly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), reduced the risk of different types of cancer, including breast cancer. Moreover, they can counteract breast cancer progression and reduce the side effects of chemotherapy in breast cancer survival. Studies have demonstrated that DHA, exhibiting greater antitumor activity than EPA in breast cancer, can be attributed to its direct impact on breast cancer cells and also due to its conversion into various metabolites. N-docosahexaenoyl ethanolamine, DHEA, is the most studied DHA derivative for its therapeutic potential in breast cancer. In this review, we emphasize the significance of dietary habits and the consumption of N-3 polyunsaturated fatty acids, particularly DHA, and we describe the current knowledge on the antitumoral action of DHA and its derivative DHEA in the treatment of breast cancer.

Nutrition Strategies Promoting Healthy Aging: From Improvement of Cardiovascular and Brain Health to Prevention of Age-Associated Diseases

BACKGROUND

An increasing number of studies suggest that diet plays an important role in regulating aging processes and modulates the development of the most important age-related diseases.

OBJECTIVE

The aim of this review is to provide an overview of the relationship between nutrition and critical age-associated diseases.

METHODS

A literature review was conducted to survey recent pre-clinical and clinical findings related to the role of nutritional factors in modulation of fundamental cellular and molecular mechanisms of aging and their role in prevention of the genesis of the diseases of aging.

RESULTS

Studies show that the development of cardiovascular and cerebrovascular diseases, neurodegenerative diseases, cognitive impairment and dementia can be slowed down or prevented by certain diets with anti-aging action. The protective effects of diets, at least in part, may be mediated by their beneficial macro- (protein, fat, carbohydrate) and micronutrient (vitamins, minerals) composition.

CONCLUSIONS

Certain diets, such as the Mediterranean diet, may play a significant role in healthy aging by preventing the onset of certain diseases and by improving the aging process itself. This latter can be strengthened by incorporating fasting elements into the diet. As dietary recommendations change with age, this should be taken into consideration as well, when developing a diet tailored to the needs of elderly individuals. Future and ongoing clinical studies on complex anti-aging dietary interventions translating the results of preclinical investigations are expected to lead to novel nutritional guidelines for older adults in the near future.

Current Evidence on the Association of Micronutrient Malnutrition with Mild Cognitive Impairment, Frailty, and Cognitive Frailty among Older Adults: A Scoping Review

Micronutrient malnutrition is thought to play an important role in the cause of cognitive impairment and physical frailty. The purpose of this scoping review was to map current evidence on the association between micronutrient deficiency in blood and mild cognitive impairment, frailty, and cognitive frailty among older adults. The scoping review was conducted based on the 2005 methodological framework by Arksey and O'Malley. The search strategy for potential literature on micronutrient concentration in blood and cognitive frailty was retrieved based on the keywords using electronic databases (PubMed, Cochrane Library, Google Scholar, Ovid, and Science Direct) from January 2010 to December 2021. Gray literature was also included in the searches. A total of 4310 articles were retrieved and 43 articles were incorporated in the review. Findings revealed a trend of significant association between low levels of B vitamins (folate and vitamin B12), vitamin D, vitamin A, vitamin E, omega 3 fatty acid, and albumin, and high homocysteine levels in blood with an increased risk of mild cognitive impairment among older adults. The results also indicated that low vitamin D levels, albumin, and antioxidants (lutein and zeaxanthin) in blood were significantly associated with frailty among older adults, while β-cryptoxanthin and zeaxanthin in blood were inversely associated with the risk of cognitive frailty. Vitamin D and antioxidants seemed to be targeted nutrients for the prevention of cognitive frailty. In conclusion, a wide range of micronutrient deficiency was associated with either mild cognitive impairment or frailty; however, little evidence exists on the dual impairment, i.e., cognitive frailty. This scoping review can serve as preliminary evidence for the association between micronutrient deficiency in blood and mild cognitive impairment, frailty, and cognitive frailty among older adults and prove the relevancy of the topic for future systematic reviews.

Calanus Oil Supplementation Does Not Further Improve Short-Term Memory or Brain-Derived Neurotrophic Factor in Older Women Who Underwent Exercise Training

Purpose

In our study, we examined changes in short-term episodic memory and brain-derived neurotrophic factor (BDNF) in women after an exercise program alone or in combination with omega-3 polyunsaturated fatty acid (n-3 PUFA) supplementation.

Patients and Methods

Fifty-five healthy elderly women (65–80 years) were randomly split into two groups: in the first group were women attending an exercise program while taking wax esters-rich oil (Calanus) supplementation (n = 28) and in the other group were women undergoing the same exercise program while taking placebo (n = 27). The 16-week exercise program consisted of functional circuit training (twice a week) and Nordic walking lessons (once a week). Short-term episodic memory was evaluated by the Czech screening Test “Pojmenování OBrázků A jejich Vybavení” (POBAV) baseline and after the program lasting 16 weeks.

Results

Our results show that short-term memory significantly improved following the exercise program, but there was no added value in using n-3 PUFA supplements. BDNF values did not differ between baseline and follow-up in either group. However, there was a statistically significant positive relationship between relative change (%) in the POBAV test and VO₂peak in the placebo group (r = 0.49).

Conclusion

Despite the added value of n-3 PUFA supplementation not being proven, our results may strengthen the importance of physical activity in averting age-related memory decline and dementia.

Advances on Therapeutic Strategies for Alzheimer’s Disease: From Medicinal Plant to Nanotechnology

Alzheimer’s disease (AD) is a chronic dysfunction of neurons in the brain leading to dementia. It is characterized by gradual mental failure, abnormal cognitive functioning, personality changes, diminished verbal fluency, and speech impairment. It is caused by neuronal injury in the cerebral cortex and hippocampal area of the brain. The number of individuals with AD is growing at a quick rate. The pathology behind AD is the progress of intraneuronal fibrillary tangles, accumulation of amyloid plaque, loss of cholinergic neurons, and decrease in choline acetyltransferase. Unfortunately, AD cannot be cured, but its progression can be delayed. Various FDA-approved inhibitors of cholinesterase enzyme such as rivastigmine, galantamine, donepezil, and NDMA receptor inhibitors (memantine), are available to manage the symptoms of AD. An exhaustive literature survey was carried out using SciFinder’s reports from Alzheimer’s Association, PubMed, and Clinical Trials.org. The literature was explored thoroughly to obtain information on the various available strategies to prevent AD. In the context of the present scenario, several strategies are being tried including the clinical trials for the treatment of AD. We have discussed pathophysiology, various targets, FDA-approved drugs, and various drugs in clinical trials against AD. The goal of this study is to shed light on current developments and treatment options, utilizing phytopharmaceuticals, nanomedicines, nutraceuticals, and gene therapy.

Sphingolipids and DHA Improve Cognitive Deficits in Aged Beagle Dogs

Canine cognitive dysfunction syndrome (CDS) is a disorder found in senior dogs that is typically defined by the development of specific behavioral signs which are attributed to pathological brain aging and no other medical causes. One way of objectively characterizing CDS is with the use of validated neuropsychological test batteries in aged Beagle dogs, which are a natural model of this condition. This study used a series of neuropsychological tests to evaluate the effectiveness of supplementation with a novel lipid extract containing porcine brain-derived sphingolipids (Biosfeen®) and docosahexaenoic acid (DHA) for attenuating cognitive deficits in aged Beagles. Two groups (n = 12), balanced for baseline cognitive test performance, received a daily oral dose of either test supplement, or placebo over a 6-month treatment phase. Cognitive function was evaluated using the following tasks: delayed non-matching to position (DNMP), selective attention, discrimination learning retention, discrimination reversal learning, and spatial discrimination acquisition and reversal learning. The effect of the supplement on brain metabolism using magnetic resonance spectroscopy (MRS) was also examined. A significant decline (p = 0.02) in DNMP performance was seen in placebo-treated dogs, but not in dogs receiving the supplement, suggesting attenuation of working memory performance decline. Compared to placebo, the supplemented group also demonstrated significantly improved (p = 0.01) performance on the most difficult pattern of the spatial discrimination task and on reversal learning of the same pattern (p = 0.01), potentially reflecting improved spatial recognition and executive function, respectively. MRS revealed a significant increase (p = 0.048) in frontal lobe glutamate and glutamine in the treatment group compared to placebo, indicating a physiological change which may be attributed to the supplement. Decreased levels of glutamate and glutamine have been correlated with cognitive decline, suggesting the observed increase in these metabolites might be linked to the positive cognitive effects found in the present study. Results of this study suggest the novel lipid extract may be beneficial for counteracting age-dependent deficits in Beagle dogs and supports further investigation into its use for treatment of CDS. Additionally, due to parallels between canine and human aging, these results might also have applicability for the use of the supplement in human cognitive health.

A Dichotomous Role for FABP7 in Sleep and Alzheimer's Disease Pathogenesis: A Hypothesis

Fatty acid binding proteins (FABPs) are a family of intracellular lipid chaperone proteins known to play critical roles in the regulation of fatty acid uptake and transport as well as gene expression. Brain-type fatty acid binding protein (FABP7) is enriched in astrocytes and has been implicated in sleep/wake regulation and neurodegenerative diseases; however, the precise mechanisms underlying the role of FABP7 in these biological processes remain unclear. FABP7 binds to both arachidonic acid (AA) and docosahexaenoic acid (DHA), resulting in discrete physiological responses. Here, we propose a dichotomous role for FABP7 in which ligand type determines the subcellular translocation of fatty acids, either promoting wakefulness aligned with Alzheimer's pathogenesis or promoting sleep with concomitant activation of anti-inflammatory pathways and neuroprotection. We hypothesize that FABP7-mediated translocation of AA to the endoplasmic reticulum of astrocytes increases astrogliosis, impedes glutamatergic uptake, and enhances wakefulness and inflammatory pathways via COX-2 dependent generation of pro-inflammatory prostaglandins. Conversely, we propose that FABP7-mediated translocation of DHA to the nucleus stabilizes astrocyte-neuron lactate shuttle dynamics, preserves glutamatergic uptake, and promotes sleep by activating anti-inflammatory pathways through the peroxisome proliferator-activated receptor-γ transcriptional cascade. Importantly, this model generates several testable hypotheses applicable to other neurodegenerative diseases, including amyotrophic lateral sclerosis and Parkinson's disease.

Marine n-3 fatty acids and cognitive change among older adults in the VITAL randomized trial

Introduction

: Few large, randomized trials have evaluated marine n-3 supplements and cognition in healthy older adults.

Methods

: Healthy community-dwelling participants aged 60+ years (mean [standard deviation] = 70.9 [5.8] years) in VITAL (randomized trial of n-3 fats [1 g/day, including 840 mg of eicosapentaenoic acid + docosahexaenoic acid] and vitamin D) were included: 3424 whose cognition was assessed by phone (VITAL-Cog; eight neuropsychological tests; 2.8 years) and 794 evaluated in person (CTSC-Cog; nine tests; 2.0 years). The primary outcome was a global score (average of test z-scores) of change over two assessments. We used multivariable-adjusted linear mixed models; substudy-specific results were meta-analyzed.

Results

: We observed no significant effect of n-3 supplementation: the mean difference in annual rate of cognitive change for the n-3 versus placebo group was -0.01 standard units (95% confidence interval [CI]: -0.02, 0.003) in VITAL-Cog and -0.002 (95% CI: -0.04, 0.03) in CTSC-Cog; the pooled difference was -0.01 (95% CI: -0.02, 0.003; P = .15).

Discussion

: Marine n-3 supplementation (1 g/day) did not confer cognitive benefits over 2 to 3 years in community-dwelling older adults.

Possibility for Prevention of Type 2 Diabetes Mellitus and Dementia Using Three Kinds of Brown Rice Blends after High-Pressure Treatment

As it has been reported that type 2 diabetes mellitus increases the risk of Alzheimer’s disease, we investigated how to prevent type 2 diabetes and dementia using biofunctional boiled rice. We adopted unpolished super-hard rice (SHBR) for diabetes and wax-free unpolished black rice (WFBBR) for dementia and blended those with ordinary non-polished rice (KBR) (blending ratio 4:4:2), adding 2.5% waxy black rice bran (WBB) and 0.3% rice oil after high-pressure treatment (HPT) (WFBSK) to improve its palatability. This boiled rice is rich in dietary fiber, anthocyanin, free ferulic acid and β-secretase inhibitory activity. A randomized, parallel-group comparison study was conducted for 12 weeks with 24 subjects, using Cognitrax to evaluate their cognitive function primarily. Furthermore, as the secondary purpose, we performed a single-dose test for postprandial blood glucose and insulin secretion at the end of the human intervention test. After 12 weeks, consumers of the WFBSK rice exhibited significant improvement in language memory by cognitive test battery compared with those who consumed the control white rice (p < 0.05). Moreover, subjects who consumed the WFBSK rice had lower insulin secretion levels than those who consumed the control polished rice (p < 0.05).

Genetic and non-genetic tailoring of microalgae for the enhanced production of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) - A review

The myriad health benefits associated with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) laid the path for their application in the functional foods and nutraceutical industries. Fish being primarily exploited for extraction of EPA and DHA are unsustainable sources; thus, oleaginous microalgae turn out to be an alternative sustainable source. This review paper aims to provide the recent developments in the context of enhancing EPA and DHA production by utilising non-genetic tailoring and genetic tailoring methods. We have also summarized the legislation, public perception, and possible risks associated with the usage of genetically modified microalgae focusing on EPA and DHA production.

Macronutrients and energy in home-prepared enteral tube feeding: Comparison between food composition table estimates, nutrition labels, and laboratory analysis

BACKGROUND

The effectiveness of home enteral nutrition depends on the supply and delivery of the prescribed nutrients. This study compared the macronutrient and energy values of home-prepared enteral tube feeding analyzed in the laboratory with the same information calculated from labels and food composition tables.

METHODS

A total of 107 enteral formulations were analyzed: 66 commercial enteral formulas (CEFs), 19 homemade enteral preparations, and 22 blended enteral preparations (BEPs). The values of macronutrients and energy and the ratio between the values found in the laboratory and the calculated values were all evaluated. The tolerance limit of acceptable variation was 20%. The results were subjected to chemometric methods using principal component analysis (PCA) and hierarchical cluster analysis (HCA).

RESULTS

In the three categories of the enteral formulations, the calculated values for protein and fat were higher than those obtained in the laboratory. The calculated values for energy were higher than those obtained in the laboratory for the BEPs and CEFs. The CEFs had the highest percentage within the limit of acceptable variation for carbohydrate and protein, whereas the BEPs presented the lowest values for fat and energy. In the exploratory analysis of data using PCA and HCA, it was possible to verify similarities and discrepancies between the enteral formulations analyzed in the laboratory with those calculated from the labels and food composition tables.

CONCLUSION

The enteral formulations showed differences between the values of macronutrients and energy analyzed in the laboratory and those calculated from labels and/or food composition tables.

Nutrients, Cognitive Function, and Brain Aging: What We Have Learned from Dogs

Due to a difference in genetics, environmental factors, and nutrition, just like in people, dogs age at different rates. Brain aging in people and dogs share similar morphological changes including irreversible cortical atrophy, cerebral amyloid angiopathy, and ventricular enlargement. Due to severe and irreversible brain atrophy, some aging dogs develop cognitive dysfunction syndrome (CDS), which is equivalent to dementia or Alzheimer’s disease (AD) in people. The risk factors and causes of CDS in dogs have not been fully investigated, but age, gender, oxidative stress, and deficiency of sex hormones appears to be associated with increased risk of accelerated brain aging and CDS in dogs. Both AD and CDS are incurable diseases at this moment, therefore more efforts should be focused on preventing or reducing brain atrophy and minimizing the risk of AD in people and CDS in dogs. Since brain atrophy leads to irreversible cognitive decline and dementia, an optimal nutritional solution should be able to not only enhance cognitive function during aging but also reduce irreversible brain atrophy. Up to now, only one nutritional intervention has demonstrated both cognition-enhancing benefits and atrophy-reducing benefits.

Delineation of Neuroprotective Effects and Possible Benefits of AntioxidantsTherapy for the Treatment of Alzheimer's Diseases by Targeting Mitochondrial-Derived Reactive Oxygen Species: Bench to Bedside

Alzheimer's disease (AD) is considered the sixth leading cause of death in elderly patients and is characterized by progressive neuronal degeneration and impairment in memory, language, etc. AD is characterized by the deposition of senile plaque, accumulation of fibrils, and neurofibrillary tangles (NFTs) which are responsible for neuronal degeneration. Amyloid-β (Aβ) plays a key role in the process of neuronal degeneration in the case of AD. It has been reported that Aβ is responsible for the production of reactive oxygen species (ROS), depletion of endogenous antioxidants, increase in intracellular Ca²⁺ which further increases mitochondria dysfunctions, oxidative stress, release of pro-apoptotic factors, neuronal apoptosis, etc. Thus, oxidative stress plays a key role in the pathogenesis of AD. Antioxidants are compounds that have the ability to counteract the oxidative damage conferred by ROS. Therefore, the antioxidant therapy may provide benefits and halt the progress of AD to advance stages by counteracting neuronal degeneration. However, despite the beneficial effects imposed by the antioxidants, the findings from the clinical studies suggested inconsistent results which might be due to poor study design, selection of the wrong antioxidant, inability of the molecule to cross the blood-brain barrier (BBB), treatment in the advanced state of disease, etc. The present review insights into the neuroprotective effects and limitations of the antioxidant therapy for the treatment of AD by targeting mitochondrial-derived ROS. This particular article will certainly help the researchers to search new avenues for the treatment of AD by utilizing mitochondrial-derived ROS-targeted antioxidant therapies.

On the Structure and Flip-flop of Free Docosahexaenoic Acid in a Model Human Brain Membrane

Among the omega-3 fatty acids, docosahexaenoic acid (DHA, sn22:6) is particularly vital in human brain cell membranes. There is considerable interest in DHA because low-level DHA has been associated with declined cognitive function and poor visual acuity. In this work, atomistic molecular dynamics simulations were used to investigate the effects of free protonated DHA (DHAP) in molar fractions of 0, 17, 30, and 38% in a realistic model of a healthy brain cell membrane comprising 26 lipid types. Numerous flip-flop events of DHAP were observed and categorized as successful or aborted. Novel use of the machine learning technique, density-based spatial clustering of applications with noise (DBSCAN), effectively identified flip-flop events by way of clustering. Our data show that increasing amounts of DHAP in the membrane disorder the bilayer packing, fluidize the membrane, and increase the rates of successful flip-flop from k = 0.2 μs^-1 (17% DHAP) to 0.8 μs^-1 (30% DHAP) and to 1.3 μs^-1 (38% DHAP). In addition, we also provided a detailed understanding of the flip-flop mechanism of DHAP across this complex membrane. Interestingly, we noted the role of hydrogen bonds in two distinct coordinated flip-flop phenomena between two DHAP molecules: double flip-flop and assisted flip-flop. Understanding the effects of various concentrations of DHAP on the dynamics within a lipid membrane and the resulting structural properties of the membrane are important when considering the use of DHAP as a dietary supplement or as a potential therapeutic.

Plasma polyunsaturated fatty acids and mental disorders in adolescence and early adulthood: cross-sectional and longitudinal associations in a general population cohort

Polyunsaturated fatty acids (PUFAs) may be pertinent to the development of mental disorders, for example via modulation of inflammation and synaptogenesis. We wished to examine cross-sectional and longitudinal associations between PUFAs and mental disorders in a large cohort of young people. Participants in the Avon Longitudinal Study of Parents and Children were interviewed and provided blood samples at two sampling periods when approximately 17 and 24 years old. Plasma PUFA measures (total omega-6 [n-6], total omega-3 [n-3], n-6:n-3 ratio and docosahexaenoic acid [DHA] percentage of total fatty acids) were assessed using nuclear magnetic resonance spectroscopy. Cross-sectional and longitudinal associations between standardised PUFA measures and three mental disorders (psychotic disorder, moderate/severe depressive disorder and generalised anxiety disorder [GAD]) were measured by logistic regression, adjusting for age, sex, body mass index and cigarette smoking. There was little evidence of cross-sectional associations between PUFA measures and mental disorders at age 17. At age 24, the n-6:n-3 ratio was positively associated with psychotic disorder, depressive disorder and GAD, while DHA was inversely associated with psychotic disorder. In longitudinal analyses, there was evidence of an inverse association between DHA at age 17 and incident psychotic disorder at age 24 (adjusted odds ratio 0.44, 95% confidence interval 0.22-0.87) with little such evidence for depressive disorder or GAD. There was little evidence for associations between change in PUFA measures from 17 to 24 years and incident mental disorders at 24 years. These findings provide support for associations between PUFAs and mental disorders in early adulthood, and in particular, for DHA in adolescence in relation to prevention of psychosis.

Associations of Omega-3 fatty acids with brain morphology and volume in cognitively healthy older adults: A narrative review

INTRODUCTION

Human neurodevelopment is complete by the 4th decade of life at which point brain atrophy ensues with variable rate and regionality into old age. Literally all regions of the brain experience atrophy with older age, however the pattern and rate of atrophy can dictate the behavioral consequences (i.e., cognitive impairment, Alzheimer's disease). Substantial research has aimed to discover the reasons why some people experience greater morphologic changes that produce undesirable consequences with aging and how it may be prevented. One possible explanation is diet, particularly fish consumption and the intake of omega-3 polyunsaturated fatty acids (omega 3) concentrated in fish oil. This narrative review examines the available evidence on the association between omega-3 and brain volume in non-demented older adults.

METHODS

A PubMed search of the literature was conducted in search of studies that investigated the associations of omega-3 on brain morphology and volume in cognitively intact older adults. Inclusion criteria were: populations of adults aged 45 years or over, who were cognitively intact, free of any central nervous system disease, and free of advanced structural brain atrophy. Study participants had to have DHA and EPA levels measured either by blood testing or scoring of dietary intake. There were no restrictions to dates of publication. Studies including demented participants, or participants with substantial white or grey matter atrophy visible on magnetic resonance imaging were excluded.

RESULTS AND CONCLUSION

The search identified only 12 studies, 8 of which were cross-sectional observational studies, 3 longitudinal observational studies, and 1 randomized controlled trial published between 2007 and 2019. The largest amount of evidence indicated that the hippocampus was most frequently involved in this association, with a higher volume associated with higher omega-3 levels. Larger total grey matter, total brain volume, and lower white matter lesion volume were also associated with higher omega-3 among four of the reviewed studies. However, most studies reviewed provided mixed findings regarding the presence or absence of the association of interest, and the findings were observed to be brain region-dependent. Current evidence is still insufficient to formulate recommendations for omega-3 intake to support brain health specifically.

Nutritional Management of Behavior and Brain Disorders in Dogs and Cats

There are several natural products and functional ingredients that, either alone or in combination with other ingredients, have shown evidence for decreasing signs associated with cognitive dysfunction and anxiety in dogs and cats, and in management of seizures in dogs with epilepsy. The evidence supporting the role that a healthy gastrointestinal tract plays in behavior is also growing as more is learned about the gut-brain axis. Nutritional support may play an important role in therapy for certain brain disorders and behavioral problems, in conjunction with other aspects of management. A multimodal approach provides the greatest likelihood of success.

Improvement of Oxidative Stress and Mitochondrial Dysfunction by β-Caryophyllene: A Focus on the Nervous System

Mitochondrial dysfunction results in a series of defective cellular events, including decreased adenosine triphosphate (ATP) production, enhanced reactive oxygen species (ROS) output, and altered proteastasis and cellular quality control. An enhanced output of ROS may damage mitochondrial components, such as mitochondrial DNA and elements of the electron transport chain, resulting in the loss of proper electrochemical gradient across the mitochondrial inner membrane and an ensuing shutdown of mitochondrial energy production. Neurons have an increased demand for ATP and oxygen, and thus are more prone to damage induced by mitochondrial dysfunction. Mitochondrial dysfunction, damaged electron transport chains, altered membrane permeability and Ca²⁺ homeostasis, and impaired mitochondrial defense systems induced by oxidative stress, are pathological changes involved in neurodegenerative disorders. A growing body of evidence suggests that the use of antioxidants could stabilize mitochondria and thus may be suitable for preventing neuronal loss. Numerous natural products exhibit the potential to counter oxidative stress and mitochondrial dysfunction; however, science is still looking for a breakthrough in the treatment of neurodegenerative disorders. β-caryophyllene is a bicyclic sesquiterpene, and an active principle of essential oils derived from a large number of spices and food plants. As a selective cannabinoid receptor 2 (CB2) agonist, several studies have reported it as possessing numerous pharmacological activities such as antibacterial (e.g., Helicobacter pylori), antioxidant, anti-inflammatory, analgesic (e.g., neuropathic pain), anti-neurodegenerative and anticancer properties. The present review mainly focuses on the potential of β-caryophyllene in reducing oxidative stress and mitochondrial dysfunction, and its possible links with neuroprotection.

Docosahexaenoic and Arachidonic Acids as Neuroprotective Nutrients throughout the Life Cycle

The role of docosahexaenoic acid (DHA) and arachidonic acid (AA) in neurogenesis and brain development throughout the life cycle is fundamental. DHA and AA are long-chain polyunsaturated fatty acids (LCPUFA) vital for many human physiological processes, such as signaling pathways, gene expression, structure and function of membranes, among others. DHA and AA are deposited into the lipids of cell membranes that form the gray matter representing approximately 25% of the total content of brain fatty acids. Both fatty acids have effects on neuronal growth and differentiation through the modulation of the physical properties of neuronal membranes, signal transduction associated with G proteins, and gene expression. DHA and AA have a relevant role in neuroprotection against neurodegenerative pathologies such as Alzheimer's disease and Parkinson's disease, which are associated with characteristic pathological expressions as mitochondrial dysfunction, neuroinflammation, and oxidative stress. The present review analyzes the neuroprotective role of DHA and AA in the extreme stages of life, emphasizing the importance of these LCPUFA during the first year of life and in the developing/prevention of neurodegenerative diseases associated with aging.

Z-score neurofeedback, heart rate variability biofeedback, and brain coaching for older adults with memory concerns

BACKGROUND

The three-month, multi-domain Memory Boot Camp program incorporates z-score neurofeedback (NFB), heart rate variability (HRV) biofeedback, and one-on-one coaching to teach memory skills and encourage behavior change in diet, sleep, physical fitness, and stress reduction.

OBJECTIVE

This prospective trial evaluates the Memory Boot Camp program for adults ages 55 to 85 with symptoms of Mild Cognitive Impairment (MCI) and subjective memory complaints.

METHODS

Participants were evaluated via the Montreal Cognitive Assessment (MoCA), NeuroTrax Global Cognitive Score, measures of anxiety, depression, sleep, quality of life, quantitative electroencephalography (QEEG), and HRV parameters at four timepoints: baseline, pre-program, post-program, and follow-up. The trial included a three-month waiting period between baseline and pre-program, such that each participant acted as their own control, and follow-up took place six months after completion of the program.

RESULTS

Participants' MoCA scores and self-reported measures of anxiety, depression, sleep quality, and quality of life improved after treatment, and these changes were maintained at follow-up. Physiological changes in HRV parameters after treatment were not significant, however, breathing rate and QEEG parameters were improved at post-program and maintained at follow-up. Finally, participants' improvement in MoCA score over the treatment period was correlated with their improvement in two brain oscillation parameters targeted by the z-score NFB protocol: relative power of delta and relative power of theta.

CONCLUSIONS

Trial results suggest that the Memory Boot Camp program is a promising treatment strategy for older adults with symptoms of MCI and subjective memory complaints.

Current Strategies and Novel Drug Approaches for Alzheimer Disease

Alzheimer's Disease (AD) is a chronic, devastating dysfunction of neurons in the brain leading to dementia. It mainly arises due to neuronal injury in the cerebral cortex and hippocampus area of the brain and is clinically manifested as a progressive mental failure, disordered cognitive functions, personality changes, reduced verbal fluency and impairment of speech. The pathology behind AD is the formation of intraneuronal fibrillary tangles, deposition of amyloid plaque and decline in choline acetyltransferase and loss of cholinergic neurons. Tragically, the disease cannot be cured, but its progression can be halted. Various cholinesterase inhibitors available in the market like Tacrine, Donepezil, Galantamine, Rivastigmine, etc. are being used to manage the symptoms of Alzheimer's disease. The paper's objective is to throw light not only on the cellular/genetic basis of the disease, but also on the current trends and various strategies of treatment including the use of phytopharmaceuticals and nutraceuticals. Enormous literature survey was conducted and published articles of PubMed, Scifinder, Google Scholar, Clinical Trials.org and Alzheimer Association reports were studied intensively to consolidate the information on the strategies available to combat Alzheimer's disease. Currently, several strategies are being investigated for the treatment of Alzheimer's disease. Immunotherapies targeting amyloid-beta plaques, tau protein and neural pathways are undergoing clinical trials. Moreover, antisense oligonucleotide methodologies are being approached as therapies for its management. Phytopharmaceuticals and nutraceuticals are also gaining attention in overcoming the symptoms related to AD. The present review article concludes that novel and traditional therapies simultaneously promise future hope for AD treatment.

A Walnut Diet in Combination with Enriched Environment Improves Cognitive Function and Affects Lipid Metabolites in Brain and Liver of Aged NMRI Mice

This in vivo study aimed to test if a diet enriched with 6% walnuts alone or in combination with physical activity supports healthy ageing by changing the oxylipin profile in brain and liver, improving motor function, cognition, and cerebral mitochondrial function. Female NMRI mice were fed a 6% walnut diet starting at an age of 12 months for 24 weeks. One group was additionally maintained in an enriched environment, one group without intervention served as control. After three months, one additional control group of young mice (3 weeks old) was introduced. Motor and cognitive functions were measured using Open Field, Y-Maze, Rotarod and Passive Avoidance tests. Lipid metabolite profiles were determined using RP-LC-ESI(-)-MS/MS in brain and liver tissues of mice. Cerebral mitochondrial function was characterized by the determination of ATP levels, mitochondrial membrane potential and mitochondrial respiration. Expression of genes involved with mito- and neurogenesis, inflammation, and synaptic plasticity were determined using qRT-PCR. A 6% walnut-enriched diet alone improved spatial memory in a Y-Maze alternation test (p < 0.05) in mice. Additional physical enrichment enhanced the significance, although the overall benefit was virtually identical. Instead, physical enrichment improved motor performance in a Rotarod experiment (p* < 0.05) which was unaffected by walnuts alone. Bioactive oxylipins like hydroxy-polyunsaturated fatty acids (OH-PUFA) derived from linoleic acid (LA) were significantly increased in brain (p** < 0.01) and liver (p*** < 0.0001) compared to control mice, while OH-PUFA of α-linolenic acid (ALA) could only be detected in the brains of mice fed with walnuts. In the brain, walnuts combined with physical activity reduced arachidonic acid (ARA)-based oxylipin levels (p < 0.05). Effects of walnut lipids were not linked to mitochondrial function, as ATP production, mitochondrial membrane potential and mitochondrial respiration were unaffected. Furthermore, common markers for synaptic plasticity and neuronal growth, key genes in the regulation of cytoprotective response to oxidative stress and neuronal growth were unaffected. Taken together, walnuts change the oxylipin profile in liver and brain, which could have beneficial effects for healthy ageing, an effect that can be further enhanced with an active lifestyle. Further studies may focus on specific nutrient lipids that potentially provide preventive effects in the brain.

In Vitro and In Vivo Digestibility of Soybean, Fish, and Microalgal Oils, and Their Influences on Fatty Acid Distribution in Tissue Lipid of Mice

The digestion rates of microalgal (docosahexaenoic acid, DHA, 56.8%; palmitic acid, 22.4%), fish (DHA, 10.8%; eicosapentaenoic acid, EPA, 16.2%), and soybean oils (oleic, 21.7%; linoleic acid, 54.6%) were compared by coupling the in vitro multi-step and in vivo apparent digestion models using mice. The in vitro digestion rate estimated based on the released free fatty acids content was remarkably higher in soybean and fish oils than in microalgal oil in 30 min; however, microalgal and fish oils had similar digestion rates at longer digestion. The in vivo digestibility of microalgal oil (91.49%) was lower than those of soybean (96.50%) and fish oils (96.99%). Among the constituent fatty acids of the diet oils, docosapentaenoic acid (DPA) exhibited the highest digestibility, followed by EPA, DHA, palmitoleic, oleic, palmitic, and stearic acid, demonstrating increased digestibility with reduced chain length and increased unsaturation degree of fatty acid. The diet oils affected the deposition of fatty acids in mouse tissues, and DHA concentrations were high in epididymal fat, liver, and brain of mice fed microalgal oil. In the present study, microalgal oil showed lower in vitro and in vivo digestibility, despite adequate DHA incorporation into major mouse organs, such as the brain and liver.

Membrane modulatory effects of omega-3 fatty acids: Analysis of molecular level interactions

Bioactive omega-3 polyunsaturated fatty acids have been shown to reduce the risk of death in patients with cardiovascular disease and alleviate the symptoms of other inflammatory diseases. However, the mechanisms of action of these effects remain unclear. It has been postulated that omega-3 polyunsaturated fatty acids modify cell membranes by incorporation into the membrane and altering the signaling properties of cellular receptors. In this chapter, we explore the effects of omega-3 polyunsaturated fatty acids on cell membrane structure and function. We present a review of the current evidence for the health benefits of these compounds and explore the molecular mechanisms through which omega-3 polyunsaturated fatty acids interact with membrane lipids and modulate bilayer structure. Using computational models of multicomponent phospholipid bilayers, we assess the consequences of incorporation of these fatty acids on membrane lipid packing, water permeation, and membrane structure.

Depression and Cognitive Impairment-Extrahepatic Manifestations of NAFLD and NASH

Non-alcoholic fatty liver disease (NAFLD) and its complication non-alcoholic steatohepatitis (NASH) are important causes of liver disease worldwide. Recently, a significant association between these hepatic diseases and different central nervous system (CNS) disorders has been observed in an increasing number of patients. NAFLD-related CNS dysfunctions include cognitive impairment, hippocampal-dependent memory impairment, and mood imbalances (in particular, depression and anxiety). This review aims at summarizing the main correlations observed between NAFLD development and these CNS dysfunctions, focusing on the studies investigating the mechanism(s) involved in this association. Growing evidences point at cerebrovascular alteration, neuroinflammation, and brain insulin resistance as NAFLD/NASH-related CNS manifestations. Since the pharmacological options available for the management of these conditions are still limited, further studies are needed to unravel the mechanism(s) of NAFLD/NASH and their central manifestations and identify effective pharmacological targets.

Emulsification and oxidation stabilities of DAG-rich algae oil-in-water emulsions prepared with the selected emulsifiers

BACKGROUND

Diacylglycerol (DAG) reduces body weight, suppresses body fat accumulation, and lowers the blood lipid concentration, and docosahexaenoic acid (DHA) can reduce the risk of occurrence of coronary artery diseases.

RESULTS

DAG-rich algae oil with a high DHA content (55.9%) was synthesized via the lipase-catalyzed glycerolysis of algae oil, which consisted of triacylglycerol (43.9 mol%), DAG (40.9 mol%), and monoacylglycerol (15.2 mol%). The DAG-rich algae oil-in-water emulsions were prepared using three emulsifiers [whey protein concentrate (WPC), Tween80, and Tween80 + Span80]. The WPC-emulsion formed a thicker serum layer (6.67% at day 51) and larger oil droplets (d₃₂ , 0.37 μm at day 28) than the Tween80- and Tween80 + Span80-emulsions (3.33-4.17%; 0.26 μm), and an upper cream layer with excess oil droplets was observed in only the WPC-emulsion, indicating that WPC-emulsion possesses the lowest emulsification stability. The hydroperoxide value and reduction rate of the DHA content were higher in the WPC-emulsions than in the Tween80- and Tween80 + Span80-emulsions during storage, which suggested that the WPC-emulsion had the lowest oxidation stability.

CONCLUSION

The DAG-rich algae oil-in-water emulsion prepared with suitable emulsifiers, such as non-ionic emulsifiers, would have excellent emulsification and oxidative stabilities and provides a health benefit for special purposes in the food processing industry. © 2019 Society of Chemical Industry.

Aging membranes: Unexplored functions for lipids in the lifespan of the central nervous system

Lipids constitute a significant group of biological metabolites and the building blocks of all cell membranes. The abundance and stoichiometries of different lipid species are known to vary across the lifespan and metabolic state, yet the functional effects of these changes have been challenging to understand. Here we review the potentially powerful intersection of lipid metabolism, which determines membrane composition, and aging. We first introduce several key lipid classes that are associated with aging and aging-related disease, where they are found in organisms, and how they act on membrane structure and function. Instead of neutral lipids, which have primary roles in energy storage and homeostasis, we review known functions for polar lipids that control the physicochemical properties of cell membranes. We then focus on aging processes in the central nervous system (CNS), which is enriched in lipids and is highly dependent on membrane structure for function. Recent studies show how lipids act not just as biomarkers of aging and associated changes in the CNS, but as direct mediators of these processes. As a model system, we explore how fatty acid composition in the retina impact aging and aging-related disease. We propose that the biophysical effects of membrane structure on fundamental eukaryotic processes - mitochondrial respiration and autophagy - provide avenues by which lipid dysregulation can accelerate aging processes. Finally, we lay out ways in which an increased understanding of lipid membrane biology can be applied to studies of aging and lifespan.

Omega-3 Polyunsaturated Fatty Acids and Their Health Benefits

Omega-3 polyunsaturated fatty acids (PUFAs) include α-linolenic acid (ALA; 18:3 ω-3), stearidonic acid (SDA; 18:4 ω-3), eicosapentaenoic acid (EPA; 20:5 ω-3), docosapentaenoic acid (DPA; 22:5 ω-3), and docosahexaenoic acid (DHA; 22:6 ω-3). In the past few decades, many epidemiological studies have been conducted on the myriad health benefits of omega-3 PUFAs. In this review, we summarized the structural features, properties, dietary sources, metabolism, and bioavailability of omega-3 PUFAs and their effects on cardiovascular disease, diabetes, cancer, Alzheimer's disease, dementia, depression, visual and neurological development, and maternal and child health. Even though many health benefits of omega-3 PUFAs have been reported in the literature, there are also some controversies about their efficacy and certain benefits to human health.

Enhancing Omega-3 Long-Chain Polyunsaturated Fatty Acid Content of Dairy-Derived Foods for Human Consumption

Omega-3 polyunsaturated fatty acids (n-3 PUFA) are termed essential fatty acids because they cannot be synthesized de novo by humans due to the lack of delta-12 and delta-15 desaturase enzymes and must therefore be acquired from the diet. n-3 PUFA include α-linolenic acid (ALA, 18:3n-3), eicosapentaenoic (EPA, 20:5n-3), docosahexaenoic (DHA, 22:6n-3), and the less recognized docosapentaenoic acid (DPA, 22:5n-3). The three long-chain (≥C20) n-3 PUFA (n-3 LC-PUFA), EPA, DHA, and DPA play an important role in human health by reducing the risk of chronic diseases. Up to the present time, seafood, and in particular, fish oil-derived products, have been the richest sources of n-3 LC-PUFA. The human diet generally contains insufficient amounts of these essential FA due largely to the low consumption of seafood. This issue provides opportunities to enrich the content of n-3 PUFA in other common food groups. Milk and milk products have traditionally been a major component of human diets, but are also among some of the poorest sources of n-3 PUFA. Consideration of the high consumption of milk and its processed products worldwide and the human health benefits has led to a large number of studies targeting the enhancement of n-3 PUFA content in dairy products. The main objective of this review was to evaluate the major strategies that have been employed to enhance n-3 PUFA content in dairy products and to unravel potential knowledge gaps for further research on this topic. Nutritional manipulation to date has been the main approach for altering milk fatty acids (FA) in ruminants. However, the main challenge is ruminal biohydrogenation in which dietary PUFA are hydrogenated into monounsaturated FA and/or ultimately, saturated FA, due to rumen microbial activities. The inclusion of oil seed and vegetable oil in dairy animal diets significantly elevates ALA content, while the addition of rumen-protected marine-derived supplements is the most effective way to increase the concentration of EPA, DHA, and DPA in dairy products. In our view, the mechanisms of n-3 LC-PUFA biosynthesis pathway from ALA and the biohydrogenation of individual n-3 LC-PUFA in ruminants need to be better elucidated. Identified knowledge gaps regarding the activities of candidate genes regulating the concentrations of n-3 PUFA and the responses of ruminants to specific lipid supplementation regimes are also critical to a greater understanding of nutrition-genetics interactions driving lipid metabolism.

Nutrients in Alzheimer’s Disease: The Interaction of Diet, Drugs and Disease

In recent decades, clinical trials in Alzheimer’s disease (AD) have failed at an unprecedented rate. The etiology of AD has since come under renewed scrutiny, both to elucidate the underlying pathologies and to identify novel therapeutic strategies. Here, diet has emerged as a potential causative/protective agent. A variety of nutrients, including lipids, minerals, vitamins, antioxidants and sugars as well as broader dietary patterns and microbiotal interactions have demonstrated associations with AD. Although clinical trials have yet to definitively implicate any singular dietary element as therapeutic or causative, it is apparent that dietary preferences, likely in complex synergies, may influence the risk, onset and course of AD. This review catalogs the impact of major dietary elements on AD. It further examines an unexplored reciprocal association where AD may modulate diet, as well as how potential therapeutics may complicate these interactions. In doing so, we observe diet may have profound effects on the outcome of a clinical trial, either as a confounder of a drug/disease interaction or as a generally disruptive covariate. We therefore conclude that future clinical trials in AD should endeavor to control for diet, either in study design or subsequent analyses.

An Integrative Overview of Non-Amyloid and Non-Tau Pathologies in Alzheimer's Disease

Alzheimer's disease (AD) is a neurodegenerative disease that devastates the lives of its victims, and challenges the family members and health care infrastructures that care for them. Clinically, attempts to understand AD have focused on trying to predict the presence of, and more recently demonstrate the presence of, its characteristic amyloid plaque and neurofibrillary tangle pathologies. Fundamental research has also traditionally focused on understanding the generation, content, and pathogenicity of plaques and tangles, but in addition to this there is now an emerging independent interest in other molecular phenomena including apolipoprotein E, lipid metabolism, neuroinflammation, and mitochondrial function. While studies emphasizing the role of these phenomena have provided valuable AD insights, it is interesting that at the molecular level these entities extensively intertwine and interact. In this review, we provide a brief overview of why apolipoprotein E, lipid metabolism, neuroinflammation, and mitochondrial research have become increasingly ascendant in the AD research field, and present the case for studying these phenomena from an integrated perspective.

Low Phytanic Acid-Concentrated DHA Prevents Cognitive Deficit and Regulates Alzheimer Disease Mediators in an ApoE-/- Mice Experimental Model

Alzheimer’s disease (AD) is the main cause of dementia and cognitive impairment. It has been associated with a significant diminution of omega-3 polyunsaturated fatty acid docosahexaenoic acid (DHA) levels in the brain. Clinical trials with DHA as a treatment in neurological diseases have shown inconsistent results. Previously, we reported that the presence of phytanic acid (PhA) in standard DHA compositions could be blunting DHA’s beneficial effects. Therefore, we aimed to analyze the effects of a low PhA-concentrated DHA and a standard PhA-concentrated DHA in Apolipoprotein E knockout (ApoE^−/−) mice. Behavioral tests and protein expression of pro-inflammatory, pro-oxidant, antioxidant factors, and AD-related mediators were evaluated. Low PhA-concentrated DHA decreased Aβ, ß-amyloid precursor protein (APP), p-tau, Ca²⁺/calmodulin-dependent protein kinase II (CAMKII), caspase 3, and catalase, and increased brain derived neurotrophic factor (BDNF) when compared to standard PhA-concentrated DHA. Low PhA-concentrated DHA decreased interleukin (IL)-6 and tumor necrosis factor alpha (TNF-α) protein expression in ApoE^−/− mice when compared to standard PhA-concentrated DHA. No significant differences were found in p22phox, inducible nitric oxide synthase (iNOS), glutathione peroxidase (GPx), superoxide dismutase 1 (SOD-1), and tau protein expression. The positive actions of a low PhA-concentrated DHA were functionally reflected by improving the cognitive deficit in the AD experimental model. Therefore, reduction of PhA content in DHA compositions could highlight a novel pathway for the neurodegeneration processes related to AD.