Mediterranean diet and cognitive decline

Combined Effect of Red Wine and Mocha Pot Coffee in Mild Vascular Cognitive Impairment

OBJECTIVES

Moderate daily mocha pot coffee intake has been associated with better mood and cognition in patients with mild vascular cognitive impairment (VCI). Similarly, moderate red wine consumption has shown protective effects on cognitive disorders, including Alzheimer's disease and vascular dementia. The aim of this study was to explore the synergistic relation between red wine and coffee intake on mood and cognitive status in mild VCI patients at risk for dementia.

METHODS

A total of 300 non-demented older patients with mild VCI were asked for coffee and red wine consumption and administered with the 17-items Hamilton Depression Rating Scale (HDRS), the Mini Mental State Examination (MMSE), and the Stroop Color-Word Interference Test (Stroop T), as well as the Activities of Daily Living (ADL) and the Instrumental ADL to measure their mood status, cognitive performance, and functional independence. Linear regression models were used to test the association between variables.

RESULTS

Moderate wine drinkers tended to show the best Stroop T score at any level of coffee consumption; conversely, heavy wine consumers performed worse at the Stroop T, especially in patients reporting high coffee intake. Moderate drinkers of both coffee and wine showed the lowest HDRS scores. Finally, a progressive increase in MMSE score was evident with increasing coffee consumption, which peaks when combined with a moderate wine consumption.

CONCLUSIONS

Daily mocha pot coffee and red wine intake seem to be synergistically associated with global cognition, executive functioning, and mood status in patients with mild VCI; the association was not linear, resulting in a protective direction for moderate intake and detrimental for heavy consumption. Future studies are needed to further corroborate the present findings and the potential long-term protective effects of these dietary compounds over time.

Potential Role for Diet in Mediating the Association of Olfactory Dysfunction and Cognitive Decline: A Nationally Representative Study

In the context of a growing body of evidence associating olfactory dysfunction (OD) with cognitive decline, this cross-sectional study used data from the 2013-2014 National Health and Nutrition Examination Survey (NHANES) sample in order to explore the role of dietary intake in this association. Leveraging a nationally representative sample of U.S. adults aged 60 years and older, this study analyzed dietary patterns using exploratory factor analysis. OD was categorized based on the NHANES Pocket Smell Test, and cognitive function was measured with a battery of tests. Survey-weighted multivariable regressions and causal mediation analysis were used to examine the relationship between dietary patterns, OD, and cognitive function. Results indicated that a poor adherence to a diet rich in monounsaturated fats (MUFAs) and polyunsaturated fats (PUFAs) was independently associated with both cognitive and olfactory dysfunctions, after adjusting for sociodemographic and health factors. Moreover, the relationship between OD and cognitive decline was found to be partly mediated by adherence to such a diet. This study proposes a potential link between diet, olfactory function, and cognitive decline, highlighting the role of nutritional interventions in mitigating cognitive decline, particularly in individuals with olfactory impairment.

Nordic diet and its benefits in neurological function: a systematic review of observational and intervention studies

Introduction

Neurological disorders have been considered the major contributors to global long-term disability and lower quality of life. Lifestyle factors, such as dietary patterns, are increasingly recognized as important determinants of neurological function. Some dietary behaviors, such as Nordic diet (ND) were likely to have protective effects on brain function. However, an understanding of the effectiveness of the ND pattern to improve neurological function and brain health is not fully understood. We review the current evidence that supports the ND pattern in various aspects of neurological function and addresses both proven and less established mechanisms of action based on its food ingredients and biochemical compounds.

Methods

In this systematic review, PubMed, Web of Science, and Scopus databases were searched from inception to February 2023. Observational and intervention studies were included.

Results

Of the 627 screened studies, 5 observational studies (including three cohorts and two cross-sectional studies) and 3 intervention studies investigating the association between ND and neurological function. Observational studies investigated the association of ND with the following neurological functions: cognition, stroke, and neuropsychological function. Intervention studies investigated the effects of ND on cognition and depression.

Discussion

Despite the limited literature on ND and its association with neurological function, several aspects of ND may lead to some health benefits suggesting neuroprotective effects. The current state of knowledge attributes the possible effects of characteristic components of the ND to its antioxidant, anti-inflammatory, lipid-lowering, gut-brain-axis modulating, and ligand activities in cell signaling pathways. Based on existing evidence, the ND may be considered a recommended dietary approach for the improvement of neurological function and brain health.

Systematic review registration

[https://www.crd.york.ac.uk/prospero/], identifier [CRD2023451117].

Antioxidant and anti-inflammatory effect of olive leaf extract treatment in diabetic rat brain

OBJECTIVES

Olive (Olea europaea L.) plays a promising role in pharmaceutical, nutraceutical, and cosmetic production. On the other hand, olive leaf is widely used in folk medicine due to its antihyperglycemic activity. For this aim, possible effects of olive leaf extract (OLE) in the brain tissue of streptozotocin-induced diabetic rats were investigated.

METHODS

A total of 28 male rats were divided into four equal groups as control, diabetic (single dose of 45 mg/kg streptozotocin, i.p.), OLE (500 mg/kg/day), and diabetic + OLE groups. The study was terminated 21 days after the diabetes model was formed. At the end of the study, all the animals were sacrificed and blood and brain tissues were isolated. Relative brain weights, complete blood count, blood glycated hemoglobin, serum glucose, total protein, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, insulin, gonadal hormone levels, production and messenger ribonucleic acid (mRNA) levels of proinflammatory cytokines and mediators, total thiol, total oxidative stress, and total antioxidant status levels and fatty acid composition in brain tissue were measured in all study groups.

RESULTS

In diabetic rats, relative brain weight and serum insulin level decreased, glycated hemoglobin, oxidative stress, production and mRNA level of proinflammatory cytokines and mediators increased, hyperglycemia, hypercholesterolemia and hypertriglyceridemia, degraded fatty acid composition, anemia, leukopenia, and thrombocytopenia occurred. After OLE treatment, a remarkable improvement in most of these parameters, except gonadal hormones, has been observed in diabetic rats.

CONCLUSIONS

This study suggests that olive leaf can be a precious neuroprotective agent in diabetes.

Study of Different Personalised Dietary Plans on Eating Behaviour, Body Image and Mood in Young Female Professional Handball Players: A Randomised Controlled Trial

Low energy availability may precede or be caused by cognitive disturbances in professional athletes. Related psychological problems include disordered eating patterns, body shape preoccupation, depression or anxiety. The objective of this research was to evaluate the effects of different personalised dietary plans on psychological factors in young professional female handball players with low energy availability. This 12-week randomised clinical trial involved 21 female players aged 22 ± 4 years, 172.0 ± 5.4 cm and 68.4 ± 6.7 kg divided into three groups (FD: free diet; MD: Mediterranean diet; HAD: high antioxidant diet). Eating behaviour (Eating Attitude Test, EAT-26: diet, bulimia and oral control subscales), body image (Body Shape Questionnaire, BSQ) and mood state (Profile of Mode State, POMS: tension, vigour, anger, depression, fatigue) were assessed. All participants showed low energy availability (<30 kcal/lean mass per day). The different plans showed no significant differences between them but significant differences over time within groups for the variables: body image, Tension, Vigour and Depression (p < 0.05). Eating behaviour improved slightly but did not show statistically significant changes. Following an adequate nutritional planning for athletes seems to improve the mood and body perception of young female handball players. A longer intervention period is required to assess the differences between diets and improvement of other parameters.

Diet quality indices and changes in cognition during chemotherapy

PURPOSE

No evidence-based prevention strategies currently exist for cancer-related cognitive decline (CRCD). Although patients are often advised to engage in healthy lifestyle activities (e.g., nutritious diet), little is known about the impact of diet on preventing CRCD. This secondary analysis evaluated the association of pre-treatment diet quality indices on change in self-reported cognition during chemotherapy.

METHODS

Study participants (n = 96) completed the Block Brief Food Frequency Questionnaire (FFQ) before receiving their first infusion and the PROMIS cognitive function and cognitive abilities questionnaires before infusion and again 5 days later (i.e., when symptoms were expected to be their worst). Diet quality indices included the Dietary Approaches to Stop Hypertension (DASH), Alternate Mediterranean Diet (aMED), and a low carbohydrate diet index and their components. Descriptive statistics were generated for demographic and clinical variables and diet indices. Residualized change models were computed to examine whether diet was associated with change in cognitive function and cognitive abilities, controlling for age, sex, cancer type, treatment type, depression, and fatigue.

RESULTS

Study participants had a mean age of 59 ± 10.8 years and 69% were female. Although total diet index scores did not predict change in cognitive function or cognitive abilities, higher pre-treatment ratio of aMED monounsaturated/saturated fat was associated with less decline in cognitive function and cognitive abilities at 5-day post-infusion (P ≤ .001).

CONCLUSIONS

Higher pre-treatment ratio of monounsaturated/saturated fat intake was associated with less CRCD early in chemotherapy. Results suggest greater monounsaturated fat and less saturated fat intake could be protective against CRCD during chemotherapy.

Valorizing the usage of olive leaves, bioactive compounds, biological activities, and food applications: A comprehensive review

Olive oil production is a significant source of economic profit for Mediterranean nations, accounting for around 98 percent of global output. Olive oil usage has increased dramatically in recent years, owing to its organoleptic characteristics and rising knowledge of its health advantages. The culture of olive trees and the manufacture of industrial and table olive oil produces enormous volumes of solid waste and dark liquid effluents, involving olive leaves, pomace, and olive oil mill wastewaters. These by-products cause an economic issue for manufacturers and pose major environmental concerns. As a result, partial reuse, like other agronomical production wastes, is a goal to be achieved. Because these by-products are high in bioactive chemicals, which, if isolated, might denote components with significant added value for the food, cosmetic, and nutraceutical sectors, indeed, they include significant amounts of beneficial organic acids, carbohydrates, proteins, fibers, and phenolic materials, which are distributed differently between the various wastes depending on the olive oil production method and table olive agronomical techniques. However, the extraction and recovery of bioactive materials from chosen by-products is a significant problem of their reasonable value, and rigorous detection and quantification are required. The primary aims of this review in this context are to outline the vital bioactive chemicals in olive by-products, evaluate the main developments in extraction, purification, and identification, and study their uses in food packaging systems and safety problems.

The Role of Tryptophan Metabolites in Neuropsychiatric Disorders

In recent decades, neuropsychiatric disorders such as major depressive disorder, schizophrenia, bipolar, etc., have become a global health concern, causing various detrimental influences on patients. Tryptophan is an important amino acid that plays an indisputable role in several physiological processes, including neuronal function and immunity. Tryptophan’s metabolism process in the human body occurs using different pathways, including the kynurenine and serotonin pathways. Furthermore, other biologically active components, such as serotonin, melatonin, and niacin, are by-products of Tryptophan pathways. Current evidence suggests that a functional imbalance in the synthesis of Tryptophan metabolites causes the appearance of pathophysiologic mechanisms that leads to various neuropsychiatric diseases. This review summarizes the pharmacological influences of tryptophan and its metabolites on the development of neuropsychiatric disorders. In addition, tryptophan and its metabolites quantification following the neurotransmitters precursor are highlighted. Eventually, the efficiency of various biomarkers such as inflammatory, protein, electrophysiological, genetic, and proteomic biomarkers in the diagnosis/treatment of neuropsychiatric disorders was discussed to understand the biomarker application in the detection/treatment of various diseases.

Adherence to the Mediterranean Diet: Impact of Geographical Location of the Observations

The Mediterranean diet has emerged as a comprehensive lifestyle, including specific foods and meal composition and a set of behavioural and social features. Adherence to the Mediterranean diet has been shown to promote health and reduce the prevalence of chronic diseases. The actual implementation of the Mediterranean diet is affected by several sociocultural factors as well as geographical components. Indeed, the geographical location, such as a specific country or different areas in a country and specific latitude and climate, appears to be an important factor that may strongly affect the implementation of the Mediterranean diet or some of its principles as well as the adherence to it. Another dynamic component affecting personal nutritional choices, also regarding adherence to the Mediterranean diet and its principles, is the individual life-long trajectory of food preference and nutrition habits and awareness. In this review, we discuss the current evidence on the impact of geographical location on adherence to the Mediterranean diet.

Malnutrition is positively associated with cognitive decline in centenarians and oldest-old adults: A cross-sectional study

BACKGROUND

Cognitive decline is a growing public health concern. However, presently, only a few large-scale studies are available on the prevalence of cognitive decline worldwide, and the relationship between nutrition and cognitive decline remains unclear and requires further investigation, especially among Chinese centenarians and oldest-old adults. This study aimed to assess the prevalence of cognitive decline among Chinese centenarians and oldest-old adults, its associated factors, and explore a possible connection with nutrition, to provide new directions for the prevention of cognitive decline in Chinese centenarians and oldest-old adults.

METHODS

Based on the China Hainan Centenarian Cohort Study (CHCCS), a household survey was conducted among all the centenarians and oldest-old adults residing in 16 cities and counties of Hainan province from June 2014 to June 2016. This study included 946 centenarians and oldest-old adults (412 and 534, respectively). Cognitive function was measured using the mini-mental state examination (MMSE).

FINDINGS

The total prevalence of cognitive decline was 76·6% (725 participants). Centenarians had a significantly higher prevalence of cognitive decline compared to oldest-old adults [359 centenarians (87·1%) vs. 366 oldest-old adults (68·5%)]. Centenarians and oldest-old adults with cognitive decline had significantly lower prognostic nutritional index (PNI) and mini nutrition assessment-short form (MNA-SF) than those without cognitive decline (P < 0·05). Multivariate logistic regression analyses showed that participants with higher PNI and MNA-SF were less likely to have cognitive decline. Multivariate linear regression analyses showed that PNI and MNA-SF were positively associated with MMSE (P < 0·05).

INTERPRETATION

Malnutrition was positively associated with cognitive decline among Chinese centenarians and oldest-old adults. It is therefore important for clinicians and community health workers to pay attention to malnutrition in these populations and provide supplemental nutrients to prevent cognitive decline.

FUNDING

This work was supported by grants from the National Natural Science Foundation of China (81900357, 81903392, 81941021, 81901252, 82001476, 81802804, 81801251), the Military Medical Science and Technology Youth Incubation Program (20QNPY110, 19QNP060), the Excellent Youth Incubation Program of Chinese People's Liberation Army General Hospital (2020-YQPY-007), the Military Medicine Youth Program of Chinese People's Liberation Army General Hospital (QNF19069, QNF19068), the National Key R&D Program of China (2018YFC2000400), the National S&D Resource Sharing Service Platform Project of China (YCZYPT[2018]07), the Innovation Platform for Academinicians of Hainan Province, the Hainan Major Scientific and Technological Cooperation Project (2016KJHZ0039), the China Postdoctoral Science Foundation funded project (2019M650359, 2020M682816, 2021T140298), the Medical Big Data R&D Project of Chinese People's Liberation Army General Hospital (MBD2018030), the National Geriatric Disease Clinical Medicine Research centre Project (NCRCG-PLAGH-2017-014), the Central Health Care Scientific Research Project (W2017BJ12), the Hainan Medical and Health Research Project (16A200057), the Sanya Medical and Health Science and Technology Innovation Project (2016YW21, 2017YW22, 2018YW11), and the Clinical Scientific Research Supporting Fund of Chinese People's Liberation Army General Hospital (2017FC-CXYY-3009).

Iron Chelation Remits Memory Deficits Caused by the High-Fat Diet in a Mouse Model of Alzheimer’s Disease

Background: Obesity is a worldwide health problem that has been implicated in many diseases, including Alzheimer’s disease (AD). AD is one of the most common neurodegenerative disorders and is characterized by two pathologies, including extracellular senior plaques composed of amyloid-β (Aβ) and intracellular neurofibrillary tangles (NFTs) consisting of abnormally hyperphosphorylated tau. According to current research, a high-fat diet (HFD) could exacerbate Aβ accumulation, oxidative damage, and cognitive defects in AD mice. However, the accurate role of HFD in the pathogenesis of AD is far more unclear. Objective: To explore the accurate role of HFD in the pathogenesis of AD. Methods: Open Field, Barns Maze, Elevated zero-maze, Contextual fear condition, Tail suspension test, western blotting, immunofluorescence, Fluoro-Jade C Labeling, Perls’ Prussian blue staining, and ELISA were used. Results: HFD caused nonheme iron overload in the brains of APPswe/PS1dE9 (APP/PS1) mice. Furthermore, the administration of M30 (0.5 mg/kg) for iron chelation once every 2 days per os (p.o.) for 1 month remitted memory deficits caused by HFD in APP/PS1 mice. Notably, a variety of hematological parameters in whole blood had no difference after iron chelation. In addition, iron chelation effectively reduced synaptic impairment in hippocampus and neuronal degeneration in cortex in the HFD-fed APP/PS1 mice. Meanwhile, iron chelation decreased Aβ 1–40 and Aβ 1–42 level as well as neuroinflammation in HFD-fed APP/PS1 mice. Conclusion: These data enhance our understanding of how HFD aggravates AD pathology and cognitive impairments and might shed light on future preclinical studies.

Technology-based nutrition interventions using the Mediterranean diet: a systematic review

CONTEXT

Over the past 2 decades, overweight and obesity rates have increased exponentially, along with related comorbidities including type 2 diabetes, hypertension, cardiovascular disease, and some cancers. The Mediterranean Diet (MDiet) has been suggested as a potential way to mitigate the health burdens related to overweight and obesity.

OBJECTIVE

For this review, the literature on MDiet-focused digital interventions was examined to determine efficacy, best practices, and potential limitations.

DATA SOURCES

The search was conducted across 15 databases for relevant publications published through April 2020 in English, French, Spanish, Arabic, or Italian.

DATA EXTRACTION

Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed using a combination of keywords and phrases and evaluated independently for relevance, merit, and inclusion and exclusion criteria.

DATA ANALYSIS

The systematic literature review resulted in 15 articles that met the search criteria. Ten interventions were delivered online, and 5 were delivered via smartphone using an app. The majority of online MDiet-focused interventions were effective, particularly when modeled after evidence-based and best-practice online nutrition education interventions. Such interventions also are effective for promoting positive health behaviors and health outcomes, such as increased physical activity, increased levels of high-density lipoprotein cholesterol, and a lower total high-density lipoprotein cholesterol ratio.

CONCLUSION

Technology-based interventions to educate and promote adherence to the MDiet are successful in helping individuals achieve the stated outcomes. More research is needed to determine the efficacy of MDiet interventions delivered via smartphone apps.

Dietary Pattern, Diet Quality, and Dementia: A Systematic Review and Meta-Analysis of Prospective Cohort Studies

BACKGROUND

Diet is an important lifestyle factor that may prevent or slow the onset and progression of neurodegeneration. Some, but not all, recent studies have suggested that adherence to a healthy dietary pattern may be associated with reduced risk of dementia.

OBJECTIVE

In this meta-analysis, we systematically examined the associations between overall dietary patterns, assessed a priori and a posteriori, and risk of dementia.

METHODS

We systematically searched PubMed, Web of Science, and the Cumulative Index for Nursing and Allied Health databases from January 1, 1981 to September 11, 2019. Prospective studies published in English were included. Random-effects model was used to calculate the pooled risk ratios and 95% confidence intervals (CIs).

RESULTS

Sixteen research articles were identified in the systematic review and 12 research articles including 66,930 participants were further included for the meta-analysis. Adherence to high diet quality or a healthy dietary pattern was significantly associated with lower risk of overall dementia (pooled risk ratio = 0.82; 95% CI: 0.70, 0.95; n = 12) and Alzheimer's disease (pooled risk ratio = 0.61; 95% CI: 0.47, 0.79; n = 6) relative to those with low diet quality or an unhealthy dietary pattern. Subgroup analyses stratified by age, sex, follow-up duration, diet quality assessment approach, study location, and study quality generated similar results.

CONCLUSION

Adherence to a healthy dietary pattern was associated with lower risk of overall dementia. Further randomized controlled trials are needed to provide additional evidence about the role of a healthy diet on the development and progression of dementia.

Alzheimer's Disease and other Tauopathies: Exploring Efficacy of Medicinal Plant-Derived Compounds in Alleviating Tau-Mediated Neurodegeneration

Alzheimer's disease (AD), a major form of dementia, has been reported to affect more than 50 million people worldwide. It is characterized by the presence of amyloid-β (Aβ) plaques and hyperphosphorylated Tau-associated neurofibrillary tangles in the brain. Apart from AD, microtubule (MT)-associated protein Tau is also involved in other neurodegenerative diseases called tauopathies, including Pick's disease, frontotemporal lobar degeneration, progressive supranuclear palsy, and corticobasal degeneration. The recently unsuccessful phase III clinical trials related to Aβ-targeted therapeutic drugs indicated that alternative targets, such as Tau, should be studied to discover more effective and safer drugs. Recent drug discovery approaches to reduce AD-related Tau pathologies are primarily based on blocking Tau aggregation, inhibiting Tau phosphorylation, compensating impaired Tau function with MT-stabilizing agents, and targeting the degradation pathways in neuronal cells to degrade Tau protein aggregates. Owing to several limitations of the currently-available Tau-directed drugs, further studies are required to generate further effective and safer Tau-based disease-modifying drugs. Here, we review the studies that focused on medicinal plant-derived compounds capable of modulating the Tau protein, which is significantly elevated and hyperphosphorylated in AD and other tauopathies. We mainly considered the studies that focused on Tau protein as a therapeutic target. We reviewed several pertinent papers retrieved from PubMed and ScienceDirect using relevant keywords, with a primary focus on the Tau-targeting compounds from medicinal plants. These compounds include indolines, phenolics, flavonoids, coumarins, alkaloids, and iridoids, which have been scientifically proven to be Tau-targeting candidates for the treatment of AD.

Understanding the Link Between Maternal Overnutrition, Cardio-Metabolic Dysfunction and Cognitive Aging

Obesity has long been identified as a global epidemic with major health implications such as diabetes and cardiovascular disease. Maternal overnutrition leads to significant health issues in industrial countries and is one of the risk factors for the development of obesity and related disorders in the progeny. The wide accessibility of junk food in recent years is one of the major causes of obesity, as it is low in nutrient content and usually high in salt, sugar, fat, and calories. An excess of nutrients during fetal life not only has immediate effects on the fetus, including increased growth and fat deposition in utero, but also has long-term health consequences. Based on human studies, it is difficult to discern between genetic and environmental contributions to the risk of disease in future generations. Consequently, animal models are essential for studying the impact of maternal overnutrition on the developing offspring. Recently, animal models provided some insight into the physiological mechanisms that underlie developmental programming. Most of the studies employed thus far have focused only on obesity and metabolic dysfunctions in the offspring. These studies have advanced our understanding of how maternal overnutrition in the form of high-fat diet exposure can lead to an increased risk of obesity in the offspring, but many questions remain open. How maternal overnutrition may increase the risk of developing brain pathology such as cognitive disabilities in the offspring and increase the risk to develop metabolic disorders later in life? Further, does maternal overnutrition exacerbate cognitive- and cardio-metabolic aging in the offspring?

Functions of amyloid precursor protein in metabolic diseases

Amyloid precursor protein (APP) is a transmembrane precursor protein that is widely expressed in the central nervous system and peripheral tissues in the liver and pancreas, adipose tissue, and myotubes. APP can be cleaved by proteases in two different ways to produce a variety of short peptides, each with different physiological properties and functions. APP peptides generated by non-amyloidogenic processing can positively influence metabolism, while the peptides produced by amyloidogenic processing have the opposite effects. Here, we summarize the regulatory effects of APP and its cleavage peptides on metabolism in the central nervous system and peripheral tissues. In addition, abnormal expression and function of APP and APP-derived peptides are associated with metabolic diseases, such as type 2 diabetes, obesity, non-alcoholic fatty liver disease, and cardiovascular disease, and cancers. Pharmacological intervention of APP function or reduction of the production of peptides derived from amyloidogenic processing may be effective strategies for the prevention and treatment of Alzheimer's disease, and they may also provide new guidance for the treatment of metabolic diseases.

Consumption of Oleic Acid on the Preservation of Cognitive Functions in Japanese Elderly Individuals

We recruited 154 community-dwelling elderly individuals and conducted a cohort study to find out the nutrient intake that is suitable for maintaining cognitive function in Japanese elders. Cognitive function was evaluated by the two functional tests, the Montreal Cognitive Assessment (MoCA) and Wechsler Memory Scale-Delayed Recall (WMS-DR), and daily nutrient intake was estimated from a Brief-type Self-administered Diet History Questionnaire (BDHQ). By a multiple regression analysis, among the four major nutrients (protein, fat, carbohydrate and ash), we detected a significant correlation between the score of cognitive functions assessed by both MoCA and WMS-DR and daily consumption of fat (p = 0.0317 and p = 0.0111, respectively). Among categories of fatty acid, we found a significant correlation between the score of both MoCA and WMS-DR and consumption of monounsaturated fatty acid (MUFA) (p = 0.0157 and p = 0.0136, respectively). Finally, among MUFAs, we observed a significant correlation between the score of both MoCA and WMS-DR and consumption of oleic acid (p = 0.0405 and p = 0.0165, respectively). From these observations, we can propose that daily consumption of fat, especially in oleic acid, has a beneficial effect against cognitive decline in community-dwelling Japanese elderly individuals.

Role of plant-based diet in late-life cognitive decline: results from the Salus in Apulia Study

OBJECTIVES

Consistency among population-based studies investigating the relationship between diet and cognition in older inhabitants in the Mediterranean area is poor. The present study investigated whether diet changes over 12 years were associated with cognitive function in older people in Southern-Italy.

METHODS

From the 'Salus in Apulia Study', that includes the MICOL and GreatAGE Studies, 584 participants were selected, firstly enrolled in MICOL3 (M3) and later in the GreatAGE Study (MICOL4, M4). Foods and micronutrients intake were recorded in both studies, and global cognitive function in M4, assessed with the Mini Mental State Examination.

RESULTS

Plant-based foods, particularly coffee and vegetables, as well as vitamin A sources, were inversely associated to age-related cognitive impairment. Alcohol consumption showed a detrimental role on cognition, while red meat appeared to be beneficial in the present study, although its role is traditionally considered harmful for cognitive function.

DISCUSSION

Our study confirmed that a traditional Mediterranean dietary pattern based on agricultural products and low alcohol consumption may help to prevent/delay age-related cognitive impairment.

The return of malonyl-CoA to the brain: Cognition and other stories

Nutrients, hormones and the energy sensor AMP-activated protein kinase (AMPK) tightly regulate the intracellular levels of the metabolic intermediary malonyl-CoA, which is a precursor of fatty acid synthesis and a negative regulator of fatty acid oxidation. In the brain, the involvement of malonyl-CoA in the control of food intake and energy homeostasis has been known for decades. However, recent data uncover a new role in cognition and brain development. The sensing of malonyl-CoA by carnitine palmitoyltransferase 1 (CPT1) proteins regulates a variety of functions, such as the fate of neuronal stem cell precursors, the motility of lysosomes in developing axons, the trafficking of glutamate receptors to the neuron surface (necessary for proper synaptic function) and the metabolic coupling between astrocytes and neurons. We discuss the relevance of those recent findings evidencing how nutrients and metabolic disorders impact cognition. We also enumerate all nutritional and hormonal conditions that are known to regulate malonyl-CoA levels in the brain, reflect on protein malonylation as a new post-translational modification, and give a reasoned vision of the opportunities and challenges that future research in the field could address.

Antioxidant Effects of Oleuropein on Hydrogen Peroxide-Induced Neuronal Stress- An In Vitro Study

Background

Persistent oxidative stress can lead to chronic inflammation and mediate most chronic diseases including neurological disorders. Oleuropein has been shown to be a potent antioxidant molecule in olive oil leaf having antioxidative properties.

Objective

The aim of this study was to investigate the protective effects of oleuropein against oxidative stress in human glioblastoma cells.

Methods

Human glioblastoma cells (U87) were pretreated with oleuropein (OP) essential oil 10 µM. After 30 minutes, 100 µM H₂O₂ was added to the cells for three hours. Cell survival was quantified by colorimetric MTT assay. Glutathione level, total oxidant capacity, total antioxidant capacity and nitric oxide levels were determined by using specific spectrophotometric methods. The relative gene expression level of iNOS was performed by qRT-PCR method.

Results

According to viability results, the effective concentration of H₂O₂ (100µM) significantly decreased cell viability and oleuropein pretreatment significantly prevented the cell losses. Oleuropein regenerated total antioxidant capacity and glutathione levels decreased by H₂O₂ exposure. In addition, nitric oxide and total oxidant capacity levels were also decreased after administration of oleuropein in treated cells.

Conclusion

Oleuropein was found to have potent antioxidative properties in human glioblastoma cells. However, further studies and validations are needed in order to understand the exact neuroprotective mechanism of oleuropein.

Purified oleocanthal and ligstroside protect against mitochondrial dysfunction in models of early Alzheimer's disease and brain ageing

As components of the Mediterranean diet (MedDiet) olive polyphenols may play a crucial role for the prevention of Alzheimer's disease (AD). Since mitochondrial dysfunction is involved in both, brain ageing and early AD, effects of 10 different purified phenolic secoiridoids (hydroxytyrosol, tyrosol, oleacein, oleuroside, oleuroside aglycon, oleuropein, oleocanthal, ligstroside, ligstroside aglycone and ligustaloside B) and two metabolites (the plant metabolite elenolic acid and the mammalian metabolite homovanillic acid) were tested in very low doses on mitochondrial function in SH-SY5Y-APP₆₉₅ cells - a cellular model of early AD. All tested secoiridoids significantly increased basal adenosine triphosphate (ATP) levels in SY5Y-APP₆₉₅ cells. Oleacein, oleuroside, oleocanthal and ligstroside showed the highest effect on ATP levels and were additionally tested on mitochondrial respiration. Only oleocanthal and ligstroside were able to enhance the capacity of respiratory chain complexes. To investigate their underlying molecular mechanisms, the expression of genes associated with mitochondrial biogenesis, respiration and antioxidative capacity (PGC-1α, SIRT1, CREB1, NRF1, TFAM, complex I, IV and V, GPx1, SOD2, CAT) were determined using qRT-PCR. Exclusively ligstroside increased mRNA expression of SIRT1, CREB1, complex I, and GPx1. Furthermore, oleocanthal but not ligstroside decreased Aβ 1-40 levels in SH-SY5Y-APP₆₉₅ cells. To investigate the in vivo effects of purified secoiridoids, the two most promising compounds (oleocanthal and ligstroside) were tested in a mouse model of ageing. Female NMRI mice, aged 12 months, received a diet supplemented with 50 mg/kg oleocanthal or ligstroside for 6 months (equivalent to 6.25 mg/kg b.w.). Young (3 months) and aged (18 months) mice served as controls. Ligstroside fed mice showed improved spatial working memory. Furthermore, ligstroside restored brain ATP levels in aged mice and led to a significant life extension compared to aged control animals. Our findings indicate that purified ligstroside has outstanding performance on mitochondrial bioenergetics in models of early AD and brain ageing by mechanisms that may not interfere with Aβ production. Additionally, ligstroside expanded the lifespan in aged mice and enhanced cognitive function.

Improvement in verbal learning over the first year of antipsychotic treatment is associated with serum HDL levels in a cohort of first episode psychosis patients

To investigate whether changes in serum lipids are associated with cognitive performance in first episode psychosis (FEP) patients during their first year of antipsychotic drug treatment. One hundred and thirty-two antipsychotic-treated FEP patients were included through the TOP study along with 83 age- and gender-matched healthy controls (HC). Information regarding cognitive performance, psychotic symptoms, lifestyle, body mass index, serum lipids [total cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein cholesterol, and triglycerides] and antipsychotic treatment was obtained at baseline and after 1 year. The cognitive test battery is comprised of assessments for verbal learning, processing speed, working memory, verbal fluency, and inhibition. Mixed-effects models were used to study the relationship between changes over time in serum lipids and cognitive domains, controlling for potential confounders. There was a significant group by HDL interaction effect for verbal learning (F = 11.12, p = 0.001), where an increase in HDL levels was associated with improvement in verbal learning in FEP patients but not in HC. Practice effects, lifestyle, and psychotic symptoms did not significantly affect this relationship. Antipsychotic-treated FEP patients who increased in HDL levels during the first year of follow-up exhibited better verbal learning capacity. Further investigations are needed to clarify the underlying mechanisms.

Mediterranean and MIND Diets Containing Olive Biophenols Reduces the Prevalence of Alzheimer's Disease

The risk of Alzheimer’s disease (AD) increases with nonmodifiable conditions including age and lack of effective efficacious pharmacotherapy. During the past decades, the non-pharmacotherapy mode of treatment of dietary modification received extensive attention in AD research. In order to reduce the AD pathology and cognitive decline, various dietary patterns have been attempted including caloric restriction (CR), dietary approaches to stop hypertension (DASH), ketogenic diets (KD), Mediterranean diet (MedDi) and Mediterranean-DASH diet Intervention for Neurological Delay (MIND) diet. Higher adherence to the MedDi diet was associated with decreases in cardiovascular and neurological disorders including AD and related cognitive decline. However, another emerging healthy dietary pattern MIND diet has also been associated with slower rates of cognitive decline and significant reduction of AD rate. Olive serves as one of the building block components of MedDi and MIND diets and the exerted potential health beneficial might be suggested due to the presence of its bioactive constituents such as oleic acids and phenolic compounds (biophenols). A few trials using medical food showed an optimal result in presymptomatic or early stages of AD. The review supports the notion that MedDi and MIND diets display potential for maintaining the cognitive function as nonpharmacological agents against AD pathology and proposed preventative mechanism through the presence of olive biophenols and presents the gaps along with the future directions.

Neuropsychologists as primary care providers of cognitive health: A novel comprehensive cognitive wellness service delivery model

By virtue of their extensive knowledge base and specialized training in brain-behavior relationships, neuropsychologists are especially poised to execute a unique broad-based approach to overall cognitive wellness and should be viewed as primary care providers of cognitive health. This article will describe a novel comprehensive cognitive wellness service delivery model including cognitive health, anti-aging, lifelong wellness, and longevity-oriented practices. These practice areas include brain-based cognitive wellness, emotional and spiritually centric exploration, and related multimodality health interventions. As experts in mind-body connections, neuropsychologists can provide a variety of evidence-based treatment options, empowering patients with a sense of value and purpose. Multiple areas of clinical therapy skill-based learning, tailor-made to fit individual needs, will be discussed including: brain stimulating activities, restorative techniques, automatic negative thoughts and maladaptive thinking reduction, inflammation and pain management techniques, nutrition and culinary focused cognitive wellness, spirituality based practices and mindfulness, movement and exercise, alternative/complimentary therapies, relationship restoration/social engagement, and trauma healing/meaning. Cognitive health rests upon the foundation of counteracting mind-body connection disruptions from multiple etiologies including inflammation, chronic stress, metabolic issues, cardiac conditions, autoimmune disease, neurological disorders, infectious diseases, and allergy spectrum disorders. Superimposed on these issues are lifestyle patterns and negative health behaviors that develop as ill-fated compensatory mechanisms used to cope with life stressors and aging. The brain and body are electrical systems that can "short circuit." The therapy practices inherent in the proposed cognitive wellness service delivery model can provide preventative insulation and circuit breaking against the shock of illness.

Wine: An Aspiring Agent in Promoting Longevity and Preventing Chronic Diseases

INTRODUCTION

Moderate wine consumption is a characteristic of the Mediterranean diet. Studies around the world have shown a beneficial effect of moderate alcohol intake, especially wine, on health. This review aims to critically summarise the most recent studies that investigate the beneficial effects of moderate wine intake on human health.

METHODS

The PubMed database was comprehensively searched to identify trials published from 2013 to 2018 that investigated the association between moderate wine consumption and health.

RESULTS

The most recent studies confirm the valuable role of moderate wine consumption, especially red wine, in the prevention and treatment of chronic diseases such as cardiovascular disease, metabolic syndrome, cognitive decline, depression, and cancer. In the meantime, recent studies also highlight the beneficial role of red wine against oxidative stress and in favour of desirable gut bacteria. The beneficial role of red wine has been attributed to its phytochemical compounds, as highlighted by clinical trials, where the effect of red wine has been compared to white wine, non-alcoholic wine, other alcoholic drinks, and water.

CONCLUSIONS

Moderate wine intake, at 1⁻2 glasses per day as part of the Mediterranean diet, has been positively associated with human health promotion, disease prevention, and disease prognosis.

Phytochemical Composition of the Decoctions of Greek Edible Greens (Chórta) and Evaluation of Antioxidant and Cytotoxic Properties

Wild or semi-wild edible greens (chórta) are an integral part of the traditional Greek Mediterranean diet due to their nutritional value, containing various phytonutrients beneficial to human health. Water-based decoctions of chórta are widely consumed in Greek alternative medicine as health promoting agents. This study examined the chemical profile of the decoctions of eight edible plants, Cichorium intybus, C. endivia, C. spinosum, Crepis sancta, Sonchus asper, Carthamus lanatus, Centaurea raphanina, and Amaranthus blitum, by UPLC-ESI-HRMS and HRMS/MS analysis, to determine possibly bioactive constituents. The profiles of the plants from the Asteraceae family are dominated by the presence of phenolic acids and flavonoid derivatives, whereas the A. blitum decoction is rich in triterpene saponins. Interestingly, the Centaurea raphanina decoction was found to be extremely rich in flavanones, particularly in the aglycone pinocembrin. Further phytochemical investigation and fractionation of this extract resulted in the isolation and identification of five compounds: phlorin (1), syringin (2), pinocembrin (3), pinocembroside (4), and pinocembrin-7-O-neohesperidoside (5). The extracts were also tested for their antioxidant and differential cytotoxic activity against tumor cells. C. raphanina was found to be differentially toxic against metastatic tumor cells. In conclusion, we found that Greek edible greens are a rich source of bioactive secondary metabolites and their consumption could contribute to the maintenance of overall health.

Neuro-nutrients as anti-alzheimer's disease agents: A critical review

Alzheimer's disease (AD) is characterized by a massive neuronal death causing memory loss, cognitive impairment and behavioral alteration that ultimately lead to dementia and death. AD is a multi-factorial pathology controlled by molecular events such as oxidative stress, protein aggregation, mitochondrial dysfunction and neuro inflammation. Nowadays, there is no efficient disease-modifying treatment for AD and epidemiological studies have suggested that diet and nutrition have a significant impact on the development of this disorder. Indeed, some nutrients can protect all kind of cells, including neurons. As prevention is better than cure, life style improvement, with a special emphasis on diet, should seriously be considered as an anti-AD track and intake of nutrients promoting neuronal health is the need of the hour. Diets rich in unsaturated fatty acids, polyphenols and vitamins have been shown to protect against AD, whereas saturated fatty acids-containing diets deprived of polyphenols promote the development of the disease. Thus, Mediterranean diets, mainly composed of fruits, vegetables and omega-3 fatty acids, stand as valuable, mild and preventive anti-AD agents. This review focuses on our current knowledge in the field and how one can fight this devastating neurodegenerative disorder through the simple proper modification of our life style.

Relationship between Adherence to the Mediterranean Diet and Health-Related Quality of Life and Life Satisfaction among Older Adults

OBJECTIVES

Evaluate the relationship between adherence to the Mediterranean diet and health-related quality of life and degree of life satisfaction among older adults.

DESIGN AND SETTING

Cross-sectional descriptive study.

PARTICIPANTS

A total of 351 people older than 60 years participated in the study.

MEASUREMENTS

The Mediterranean Diet Score (MDS) was calculated to assess the degree of adherence to the MD. MD adherence was related to health-related quality of life using the Short Form Healthy Survey (SF-12) questionnaire, to life satisfaction using the Satisfaction with Life Scale (SWLS), and to sociodemographic, clinical and lifestyle variables. Multiple logistic regression models were used to analyse this relationship.

RESULTS

Mediterranean diet adherence was related to health- related quality of life. Participants with better adherence to the MD were more physically active (p=0.01) and had better health-related quality of life (p<0.05) and lower consumption of alcoholic beverages (p=0.04). The age-adjusted model showed a significant association between the MD and mental function for both sexes and with physical function only for men. The fully adjusted model showed a direct relationship between the MD and life satisfaction of women (p>0.05) but not for that of men (p=0.31).

CONCLUSIONS

The adherence to the MD is directly associated with the self-perceived physical and mental function of both sexes and with the life satisfaction of women. Further studies in older adult populations should be performed to obtain conclusive results on the MD effect on health-related quality of life, including wellness indicators.

The Role of the Gut Microbiota in the Metabolism of Polyphenols as Characterized by Gnotobiotic Mice

A growing body of experimental data suggests that microbes in the gut influence behavior and can alter brain physiology and neurochemistry. Although promising, researchers are only starting to understand the potential of the gut microbiota for use in neurological disease. Recent evidence demonstrated that gastrointestinal activities are linked to mood disorders such as anxiety, depression, and most recently, cognitive functions in age-related neurodegenerative disorders. Studies from our group and others are uncovering new evidence suggesting that the gut microbiota plays a crucial role in the metabolism and bioavailability of certain dietary compounds and synthetic drugs. Based on this evidence, this review article will discuss the implications of the gut microbiota in mechanisms of bioavailability and biotransformation with an emphasis on dietary polyphenol compounds. This will be followed by a survey of ongoing innovative research identifying the ability of individual gut bacteria to enhance the bioavailability of gut-derived, brain-penetrating, bioactive polyphenol metabolites that ultimately influence mechanisms associated with the promotion of resilience against psychological and cognitive impairment in response to stress. Lastly, current research initiatives aimed at promoting the generation of brain bioactive polyphenol metabolites by specialized gut microbes will be discussed, specifically the use of gnotobiotic mice to develop bioengineered second generation probiotics. We propose that leveraging the gut microbial ecosystem to generate brain targeted bioactive metabolites from dietary polyphenols can attenuate lifestyle risk factors and promote resilience against age-related cognitive decline.

Impact of enriched environment on production of tau, amyloid precursor protein and, amyloid-β peptide in high-fat and high-sucrose-fed rats

OBJECTIVE

The Western-type diet is associated with an elevated risk of Alzheimer's disease and other milder forms of cognitive impairment. The aim of the present study was to investigate the effects of the environmental enrichment on amyloid and tau pathology in high-fat and high-sucrose-fed rats.

METHODS

In total, 40 adult male rats were categorised into two main groups according to their housing conditions: enriched environment (EE, n=16) and standard housing condition (n=24). The groups were further divided into five subgroups that received standard diet, high-fat diet, and high-sucrose diet. We performed the analysis of amyloid β-peptide (Aβ) (1-40), Aβ(1-42), amyloid precursor protein (APP), and tau levels in the hippocampus of rats that were maintained under standard housing conditions or exposed to an EE.

RESULTS

The EE decreased the Aβ(1-40), Aβ(1-42), APP, and tau levels in high-fat and high-sucrose-fed rats.

CONCLUSION

This observation shows that EE may rescue diet-induced amyloid and tau pathology.

Mediterranean-type diet is associated with higher psychological resilience in a general adult population: findings from the Moli-sani study

BACKGROUND/OBJECTIVE

Psychological resilience is a measure of stress coping ability and has been associated with favourable health outcomes. While evidence on the relationship of dietary habits with a number of psychosocial conditions is available, there is lack of studies on their association with psychological resilience in a general adult population.

SUBJECTS/METHODS

Cross-sectional analysis on 10 812 subjects recruited within the cohort of the Moli-sani study (2005-2010). Psychological resilience was measured by the 25-item Connor-Davidson Psychological Resilience Scale. Food intake was recorded by the EPIC food frequency questionnaire and adherence to Mediterranean diet was appraised by both a Greek Mediterranean diet score and an Italian Mediterranean Index. Empirically derived dietary patterns were obtained by principal factor analysis. Multivariable linear regression analysis (95%CI) was used to test the association between dietary scores and psychological resilience.

RESULTS

Higher adherence to Mediterranean-type diets or consumption of a vegetable-based dietary pattern (obtained from principal factor analysis) were positively associated with psychological resilience (β=0.43; 95%CI: 0.19-0.66, β=0.92; 0.69-1.16, and β=1.18; 0.93-1.44, for Greek Mediterranean diet score, Italian Mediterranean Index and the 'Olive oil and vegetables pattern', respectively). Dietary polyphenol or antioxidant intakes and greater variety in fruit and vegetable consumption were also positively associated with psychological resilience, while the associations with Western-like diets were weak.

CONCLUSIONS

In conclusion, Mediterranean diet, vegetable-based dietary patterns and better diet quality were all positively associated with higher psychological resilience, whereas Western-type diets were not.

The Association between the Mediterranean Dietary Pattern and Cognitive Health: A Systematic Review

The ageing population is accompanied by increased rates of cognitive decline and dementia. Not only does cognitive decline have a profound impact on an individual's health and quality of life, but also on that of their caregivers. The Mediterranean diet (MD) has been known to aid in reducing the risk of cardiovascular diseases, cancer and diabetes. It has been recently linked to better cognitive function in the elderly population. The purpose of this review was to compile evidence based data that examined the effect of adherence to the MD on cognitive function and the risk of developing dementia or Alzheimer's disease. This review followed PRISMA guidelines and was conducted using four databases and resulted in 31 articles of interest. Cross-sectional studies and cohort studies in the non-Mediterranean region showed mixed results. However, cohort studies in the Mediterranean region and randomized controlled trials showed more cohesive outcomes of the beneficial effect of the MD on cognitive function. Although more standardized and in-depth studies are needed to strengthen the existing body of evidence, results from this review indicate that the Mediterranean diet could play a major role in cognitive health and risk of Alzheimer's disease and dementia.

Stress and adolescent hippocampal neurogenesis: diet and exercise as cognitive modulators

Adolescence is a critical period for brain maturation. Deciphering how disturbances to the central nervous system at this time affect structure, function and behavioural outputs is important to better understand any long-lasting effects. Hippocampal neurogenesis occurs during development and continues throughout life. In adulthood, integration of these new cells into the hippocampus is important for emotional behaviour, cognitive function and neural plasticity. During the adolescent period, maturation of the hippocampus and heightened levels of hippocampal neurogenesis are observed, making alterations to neurogenesis at this time particularly consequential. As stress negatively affects hippocampal neurogenesis, and adolescence is a particularly stressful time of life, it is important to investigate the impact of stressor exposure at this time on hippocampal neurogenesis and cognitive function. Adolescence may represent not only a time for which stress can have long-lasting effects, but is also a critical period during which interventions, such as exercise and diet, could ameliorate stress-induced changes to hippocampal function. In addition, intervention at this time may also promote life-long behavioural changes that would aid in fostering increased hippocampal neurogenesis and cognitive function. This review addresses both the acute and long-term stress-induced alterations to hippocampal neurogenesis and cognition during the adolescent period, as well as changes to the stress response and pubertal hormones at this time which may result in differential effects than are observed in adulthood. We hypothesise that adolescence may represent an optimal time for healthy lifestyle changes to have a positive and long-lasting impact on hippocampal neurogenesis, and to protect against stress-induced deficits. We conclude that future research into the mechanisms underlying the susceptibility of the adolescent hippocampus to stress, exercise and diet and the consequent effect on cognition may provide insight into why adolescence may be a vital period for correct conditioning of future hippocampal function.

Alzheimer's Disease: From Mitochondrial Perturbations to Mitochondrial Medicine

Age-related neurodegenerative diseases such as Alzheimer's disease (AD) are distressing conditions causing countless levels of suffering for which treatment is often insufficient or inexistent. Considered to be the most common cause of dementia and an incurable, progressive neurodegenerative disorder, the intricate pathogenic mechanisms of AD continue to be revealed and, consequently, an effective treatment needs to be developed. Among the diverse hypothesis that have been proposed to explain AD pathogenesis, the one concerning mitochondrial dysfunction has raised as one of the most discussed with an actual acceptance in the field. It posits that manipulating mitochondrial function and understanding the deficits that result in mitochondrial injury may help to control and/or limit the development of AD. To achieve such goal, the concept of mitochondrial medicine places itself as a promising gathering of strategies to directly manage the major insidious disturbances of mitochondrial homeostasis as well as attempts to directly or indirectly manage its consequences in the context of AD. The aim of this review is to summarize the evolution that occurred from the establishment of mitochondrial homeostasis perturbation as masterpieces in AD pathogenesis up until the development of mitochondrial medicine. Following a brief glimpse in the past and current hypothesis regarding the triad of aging, mitochondria and AD, this manuscript will address the major mechanisms currently believed to participate in above mentioned events. Both pharmacological and lifestyle interventions will also be reviewed as AD-related mitochondrial therapeutics.

Mediterranean Diet, Cognitive Function, and Dementia: A Systematic Review of the Evidence

A growing body of evidence suggests that adherence to the Mediterranean diet (MD) may protect against cognitive decline and dementia. Many epidemiologic studies and several randomized controlled trials (RCTs) have found positive effects of the MD on cognitive function, but findings remain inconsistent. The aim of this systematic review was to provide an update on the current knowledge of the effects of the MD on cognitive function, cognitive impairment, Alzheimer disease (AD), and all-type dementia. Five databases were searched-PubMed, Embase, CINAHL, CENTRAL, and PsycINFO (1806 to 25 May 2015)-with the use of prespecified criteria. Human studies that were published in English without any restriction on study type, population assessed, intervention period, follow-up time, or publication date, and that examined the association between adherence to the MD and cognitive function or dementia symptoms (as measured by cognitive function tests), were included. Only primary publication types were included. Thirty-two studies from 25 unique cohorts, including 5 RCTs and 27 observational studies, met the inclusion criteria. The majority of studies showed that the MD was associated with improved cognitive function, a decreased risk of cognitive impairment or decreased risk of dementia, or AD. Three studies found no correlation between the MD and AD, 3 further studies found no association between the MD and cognitive impairment, and 5 studies found no association between the MD and cognitive function. There was large heterogeneity, and studies differed with regard to quality. Based on the findings and the limitations in study design, we conclude that adherence to the MD is associated with better cognitive performance. However, it should be noted that the majority of findings come from epidemiologic studies that provide evidence for a correlation between the MD and cognition but not for a cause-and-effect relation. More controlled trials are required to establish a causational relation.

Adherence to a Mediterranean-Style Diet and Effects on Cognition in Adults: A Qualitative Evaluation and Systematic Review of Longitudinal and Prospective Trials

The Mediterranean-style diet (MedDiet) involves substantial intake of fruits, vegetables, and fish, and a lower consumption of dairy, red meat, and sugars. Over the past 15 years, much empirical evidence supports the suggestion that a MedDiet may be beneficial with respect to reducing the incidence of cardiovascular disease, cancer, metabolic syndrome, and dementia. A number of cross-sectional studies that have examined the impact of MedDiet on cognition have yielded largely positive results. The objective of this review is to evaluate longitudinal and prospective trials to gain an understanding of how a MedDiet may impact cognitive processes over time. The included studies were aimed at improving cognition or minimizing of cognitive decline. Studies reviewed included assessments of dietary status using either a food frequency questionnaire or a food diary assessment. Eighteen articles meeting our inclusion criteria were subjected to systematic review. These revealed that higher adherence to a MedDiet is associated with slower rates of cognitive decline, reduced conversion to Alzheimer's disease, and improvements in cognitive function. The specific cognitive domains that were found to benefit with improved Mediterranean Diet Score were memory (delayed recognition, long-term, and working memory), executive function, and visual constructs. The current review has also considered a number of methodological issues in making recommendations for future research. The utilization of a dietary pattern, such as the MedDiet, will be essential as part of the armamentarium to maintain quality of life and reduce the potential social and economic burden of dementia.

Targeting inflammation to influence cognitive function following spinal cord injury: a randomized clinical trial

STUDY DESIGN

This study was a randomized, parallel-group, controlled clinical trial.

OBJECTIVES

The purpose of this study was to examine the efficacy of targeting inflammation as a means of improving cognitive function in individuals with spinal cord injury.

SETTING

Participants were recruited from the Niagara region of Ontario Canada and all testing occurred on-site at Brock University.

METHODS

Indices of memory and verbal learning were assessed by means of the California Verbal Learning Test (CVLT). Inflammation and concentrations of neuroactive compounds related to the kynurenine pathway were assessed via a number of pro- and anti-inflammatory cytokines, as well as tryptophan, kynurenine and several large neutral amino acids. All assessments were performed at baseline as well as at 1 month and 3 months during a 3-month intervention by means of an anti-inflammatory diet.

RESULTS

Despite a reduction in inflammation, all measures of the CVLT, including list A, trial 1 (P=0.48), learning slope (P=0.46), long delay free recall (P=0.83), intrusions (P=0.61) and repetitions (P=0.07), showed no significant group × time interaction.

CONCLUSION

It may be possible that the reduction in inflammation achieved in the current study was insufficient to induce substantial changes in indices of verbal learning and memory. Alternatively, as these participants likely underwent years of previous chronic inflammation, the underlying hippocampal damage may have negated potential improvements induced by acute reductions in inflammation.

Influence of age-related learning and memory capacity of mice: different effects of a high and low caloric diet

BACKGROUND

Recent studies indicate that consumption of the different calorie diet may be an important way to accelerate or slow the neurodegenerative disorder related to age. Long-term consumption of a high-calorie diet affects the brain and increase the risk of neurodegenerative disorders. And consumption of a low-calorie diet (caloric restriction, CR) could delay aging, and protect the central nervous system from neurodegenerative disorders. The underlying mechanisms have not yet been clearly defined.

METHOD

Thirty 6-week-old C57/BL6 mice were randomly assigned to a NC group (fed standard diet, n = 10), a CR group (fed a low-calorie diet, n = 10) or a HC group (fed a high-calorie diet, n = 10) for 10 months. Body weight was measured monthly. Learning and memory capacity were determined by Morris water maze. Pathological changes of the hippocampus cells were detected with HE and Nissl staining. The expression of GFAP was determined by immunofluorescence and western blot. The expression of mTOR, S6K and LC3B in the hippocampus was determined by immunofluorescence.

RESULTS

After feeding for 10 months, compared with mice in the NC group, mean body weight was significantly higher in the HC group and significantly lower in the CR group. The result of Morris water maze showed that compared with mice in the NC group, the learning and memory capacity was significantly increased in the CR group, and significantly decreased in the HC group. HE and Nissl staining of the hippocampus showed cells damaged obviously in the HC group. In the hippocampus, the expression of GFAP, mTOR and S6K was increased in the HC group, and decreased in the CR group. The expression of LC3B was decreased in the HC group, and increased in the CR group.

CONCLUSIONS

Long-term consumption of a high-calorie diet could inhibit autophagy function, and facilitate neuronal loss in the hippocampus, which in turn aggravate age-related cognition impairment. And consumption of a low-calorie diet (caloric restriction, CR) could enhance the degree of autophagy, protect neurons effectively against aging and damage, and keep learning and memory capacity better.

Neuroprotective effects of metformin against Aβ-mediated inhibition of long-term potentiation in rats fed a high-fat diet

Metformin (Met) is used to treat neurodegenerative disorders such as Alzheimer's disease (AD). Conversely, high-fat diets (HFD) have been shown to increase AD risk. In this study, we investigated the neuroprotective effects of Met on β-amyloid (Aβ)-induced impairments in hippocampal synaptic plasticity in AD model rats that were fed a HFD. In this study, 32 adult male Wistar rats were randomly assigned to four groups: group I (control group, regular diet); group II (HFD+vehicle); group III (HFD+Aβ); or group IV (Met+HFD+Aβ). Rats fed a HFD were injected with Aβ to induce AD, allowed to recover, and treated with Met for 8 weeks. The rats were then anesthetized with intraperitoneal injections of urethane and placed in a stereotaxic apparatus for surgery, electrode implantation, and field potential recording. In vivo electrophysiological recordings were then performed to measure population spike (PS) amplitude and excitatory postsynaptic potential (EPSP) slope in the hippocampal dentate gyrus. Long-term potentiation (LTP) was induced by high-frequency stimulation of the perforant pathway. Blood samples were then collected to measure plasma levels of triglycerides, low-density lipoproteins, very low-density lipoprotein, and cholesterol. After induction of LTP, PS amplitude and EPSP slope were significantly decreased in Aβ-injected rats fed a HFD compared to vehicle-injected animals or untreated animals that were fed a normal diet. Met treatment of Aβ-injected rats significantly attenuated these decreases, suggesting that Met decreased the effects of Aβ on LTP. These findings suggest that Met treatment is neuroprotective against the detrimental effects of Aβ and HFDs on hippocampal synaptic plasticity.

Olive Oil and the Hallmarks of Aging

Aging is a multifactorial and tissue-specific process involving diverse alterations regarded as the "hallmarks of aging", which include genomic instability, telomere attrition, epigenetic alterations, loss of proteostasis, deregulated nutrient sensing, mitochondrial dysfunction, cellular senescence, stem cell exhaustion and altered intracellular communication. Virtually all these hallmarks are targeted by dietary olive oil, particularly by virgin olive oil, since many of its beneficial effects can be accounted not only for the monounsaturated nature of its predominant fatty acid (oleic acid), but also for the bioactivity of its minor compounds, which can act on cells though both direct and indirect mechanisms due to their ability to modulate gene expression. Among the minor constituents of virgin olive oil, secoiridoids stand out for their capacity to modulate many pathways that are relevant for the aging process. Attenuation of aging-related alterations by olive oil or its minor compounds has been observed in cellular, animal and human models. How olive oil targets the hallmarks of aging could explain the improvement of health, reduced risk of aging-associated diseases, and increased longevity which have been associated with consumption of a typical Mediterranean diet containing this edible oil as the predominant fat source.

Are a Healthy Diet and Physical Activity Synergistically Associated with Cognitive Functioning in Older Adults?

OBJECTIVES

Previous research has demonstrated that being both physically active and adhering a healthy diet is associated with improved cognitive functioning; however, it remains unclear whether these factors act synergistically. We investigated the synergistic association of a healthy diet and being physically active with cognitive functioning.

DESIGN

Cross-sectional study.

SETTING AND PARTICIPANTS

Data from the Longitudinal Aging Study Amsterdam (LASA) were used. We analyzed data from 2,165 community dwelling adults who were aged 55-85 years, 56% of whom were female. Cognitive functioning was assessed by the Mini-Mental State Examination (MMSE), an MMSE score of >26 indicates good cognitive functioning. Physical activity was assessed by the LASA Physical Activity Questionnaire and was considered sufficient if the person engaged in moderately intense physical activity ≥ 20 min/day. A healthy diet score was based on the intake of fruit, vegetables and fish. Each of the food groups was assigned a score that ranged from 1 (well below the Dutch guideline for a healthy diet) to 4 (well above the Dutch guideline for a healthy diet), and the scores were aggregated to determine a healthy diet (healthy ≥ 9 points). Multiple logistic and linear regression analyses were used to examine the (synergistic) association among physical activity, a healthy diet and cognitive functioning. All analyses were adjusted for potential chronic diseases and lifestyle confounders.

RESULTS

Of all of the participants, 25% were diagnosed with a cognitive impairment (MMSE ≤26), 80% were physically active and 41% had a healthy diet. Sixty three percent of the participants both adhered to a healthy diet and were physically active. Sufficient daily physical activity (OR=2.545 p<.001) and adherence to a healthy diet (OR=1.766 p=.002) were associated with good cognitive functioning. After adjusting for confounding factors, sufficient physical activity was not significantly related to cognitive functioning (p=.163); however adherence to a healthy diet remained significantly associated with good cognitive functioning (p=.017). No interaction among sufficient physical activity, healthy diet adherence and good cognitive functioning was observed (crude: p=.401, adjusted: p=.216).

CONCLUSION

The results of this cross-sectional study indicate that adherence to a healthy diet is inde-pendently related to cognitive functioning. Being physically active does not modify this association. Furthermore, these two lifestyle factors do not synergistically relate to cognitive functioning.

Olive Oil-derived Oleocanthal as Potent Inhibitor of Mammalian Target of Rapamycin: Biological Evaluation and Molecular Modeling Studies

The established anticancer and neuroprotective properties of oleocanthal combined with the reported role of mammalian target of rapamycin (mTOR) in cancer and Alzheimer's disease development encouraged us to examine the possibility that oleocanthal inhibits mTOR. To validate this hypothesis, we docked oleocanthal into the adenosine triphosphate binding pocket of a close mTOR protein homologue, namely, PI3K-γ. Apparently, oleocanthal shared nine out of ten critical binding interactions with a potent dual PIK3-γ/mTOR natural inhibitor. Subsequent experimental validation indicated that oleocanthal indeed inhibited the enzymatic activity of mTOR with an IC50 value of 708 nM. Oleocanthal inhibits the growth of several breast cancer cell lines at low micromolar concentration in a dose-dependent manner. Oleocanthal treatment caused a marked downregulation of phosphorylated mTOR in metastatic breast cancer cell line (MDA-MB-231). These results strongly indicate that mTOR inhibition is at least one of the factors of the reported anticancer and neuroprotective properties of oleocanthal.