Nutritional Neuroscience最新文献

Background: Recent studies have shown that ferroptosis, a newly identified regulated cell death characterized by increased lipid peroxidation and accumulation of toxic lipid peroxides, is closely related to the pathophysiological processes of nervous system diseases which can be inhibited with iron chelators, lipophilic antioxidants, and lipid peroxidation inhibitors.

Objective: To review the current evidence on the efficacy of various natural polyphenols in nervous system injury.

Methods: The data selected for this review were collected by searching the MEDLINE/PubMed, Web of Science, Scopus, and Google Scholar database for articles published in English between 2000 and 2024 using the following terms: cell death, regulated cell death, ferroptosis, lipid peroxides, iron, and glutathione peroxidase.

Results: Natural polyphenols have been found to have some protective effects against nervous system disorders, which are attributed to a variety of biological properties, particularly antioxidant, immunomodulatory, and anti-inflammatory effects. The preclinical studies conducted on the use of the most common dietary polyphenols, including resveratrol, EGCG, curcumin, quercetin, gastrodin, baicalein & baicalin, carthamin, galangin, puerarin, morachalcone, and carnosic acid with the molecular mechanisms have been discussed. On the other hand, the results of a few clinical studies emphasize the primary role of iron in neuronal degeneration following some of nervous system injury.

Conclusion: Some of the findings indicated that natural polyphenols as antioxidant supplements have anti-ferroptotic effects in nervous system disorders.

Objectives: Increasing research has shown that heavy metal as a neurotoxicant affects cognitive function across the lifespan. Nutritional status may modify susceptibility to heavy metal exposures, which further impacts cognition.

Methods: We conducted a comprehensive search for cross-sectional studies, longitudinal studies, case-control studies and clinical trials on the interaction between nutrient and heavy metal, as well as mixed heavy metal exposure, in relation to cognition across the lifespan.

Results: Six cross-sectional studies, 20 longitudinal studies, two case-control studies and two clinical trials were identified. Studies confirmed the interactions between heavy metals (e.g. iron, lead, mercury, cadmium, copper and manganese) and various nutrients (e.g. protein, minerals, vitamins and polyunsaturated fatty acids) in relation to cognition. Sufficient essential nutrients may attenuate the adverse effect of heavy metals on cognitive performance while nutritional deficiency could increase metal toxicity. These interactions can be found in infants, children, adolescents and adults. However, current studies are limited and generate mixed results across different age groups. Potential mechanisms include nutrients reducing the bioaccumulation of metal in the same food source and lowering the toxicity of metal by moderating neurochemistry.

Discussion: Further longitudinal study is necessary to explore different types of interactions, elucidate further physiological mechanisms and adjust more confounding variables to increase confidence in causal effect. A comprehensive understanding of metal-nutrient interaction in human cognition could help facilitate earlier detection and prevention.

Objectives: This review examines how food additives impact the central nervous system (CNS) focusing on the effects of sugars, artificial sweeteners, colorings, and preservatives.

Methods: A literature search of PubMed, Scopus, and Web of Science was conducted for studies published since 2010. Key search terms included, food additives, neurotoxicity, cognition, and behavior.

Results: It summarizes research findings on additives such as aspartame, stevia, methylene blue, azo dyes, sodium benzoate, and monosodium glutamate. It also covers mechanisms such as oxidative stress, neuroinflammation, and disruptions in neurotransmitter systems. Furthermore, it emphasizes the properties of natural compounds such as garlic (Allium sativum), tetramethylpyrazine, curcumin, licorice root extract (glycyrrhizin), and polyphenols in mitigating CNS damage caused by food additives.

Discussion: Although ongoing studies are expanding our knowledge on the effects of these additives, future CNS research should focus on long-term investigations involving subjects to provide a more comprehensive understanding of the cumulative impacts of different additives and update regulatory standards based on new scientific findings.

Objectives: Scientific evidence suggests an association between diet quality and the prevalence of common mental disorders (CMD) in women. Thus, this study aimed to investigate the association between a healthy dietary pattern and CMD among women.

Methods: A cross-sectional population-based study was conducted on a representative sample of 1128 women, aged 20-69 years, residing in the urban area of São Leopoldo, RS, Brazil. A validated food frequency questionnaire was used to assess dietary intake. A healthy dietary pattern, primarily consisting of fruits and vegetables, was identified using principal component analysis. CMD were evaluated using the Self-Reporting Questionnaire (SRQ-20: score ≥ 8). Prevalence ratios (PR) with 95% confidence intervals (CI) were estimated using multivariate Poisson regression with robust variance.

Results: The overall prevalence of CMD was 33.2% (95% CI: 30.6-36.1). After adjusting for potential confounding factors, a statistically significant inverse relationship between a healthy dietary pattern and CMD was observed. High adherence to a healthy dietary pattern was associated with a lower prevalence of CMD (PR = 0.74; 95% CI: 0.59-0.95; p = 0.017). Women with a higher score on the healthy dietary pattern were 26% less likely to have CMD.

Conclusions: This study highlights a significant inverse association between a healthy dietary pattern and CMD in women. A high prevalence of CMD was also observed in this population group. These findings underscore the importance of promoting healthy dietary intake to prevent psychiatric disorders.

Purpose: The incidence of obesity has surged to pandemic levels in recent decades. Approximately 1.89 million obesity are linked to excessive salt consumption. This study aims to check the toxicity of salt at different concentrations using an invertebrate model organism Drosophila melanogaster.

Methods: Drosophila food was mixed with different salt concentrations (50, 200, 400, 800 µM). The toxicity of salt in third instar larvae was checked via different experiments such as trypan blue assay, crawling assay, and other histological staining was done to check the deposition of lipid droplets and amount of reactive oxygen species. Food intake analysis was performed to check the feeding rate, and body weight was also calculated to check the obesity index. Several behavioral assays are also performed in adult flies.

Results: Most significant abnormalities were seen at 50 and 200 µM concentrations. Feeding rate increased up to 60%, body weight was increased up to 12% in larvae, and 27% in adult at 200 µM concentration. Approximately 60% larvae and 58% adult flies had defective response to extreme heat. 28% larvae and 38% adult flies were not responding to cold temperature. 55% flies had a defective phototaxis behavior and 40% of them showed positive geotaxis at those range. Salt stress leads to the buildup of free radicals, resulting in DNA damage in both the gut and hemolymph.

Findings: Most toxic consequences are observed at the lower concentration range as the feeding rate was higher. Flies show aversive response to feed on the higher concentration of salt.

Objectives: Maternal protein malnutrition alters brain functioning, impairing fetal development. Physical exercise during gestation benefits the fetal organism from maternal adaptive changes that may be neuroprotective. This study evaluated the effect of a low-protein diet associated with maternal voluntary physical activity (VPA) on rats' behavioral and brain electrophysiological parameters in the mother-pup dyad.

Methods: Female Wistar rats (n = 40) performed VPA on running wheels during a 30-day pre-mating period. Daily running distance, activity duration, and caloric expenditure enabled us to classify the dams as sedentary or exercised. During pregnancy, half of the mothers were fed a low-protein diet (8% protein from casein), and the other half was fed a standard diet with 17% protein from casein. After lactation, when the mothers reached 150-160 days and the pups aged 30-35, animals were tested to evaluate anxiety-like behaviors in the open field and the elevated plus maze, and assess object recognition memory in the open field apparatus. At 160-170 days of life (mothers) and 35-45 days (pups), the animals were subjected to a recording session of the excitability-related phenomenon known as cortical spreading depression (CSD).

Results: In the mother-pup dyad, malnutrition accelerated CSD, increased anxiety-like behavior, and impaired memory, whereas VPA produced the opposite effects. The greater impact of exercise was observed among the malnourished animals.

Discussion: Our results provide important evidence about the beneficial modulating role of perinatal VPA (before, during and up to 14 days after pregnancy) in reprograming the effects of protein malnutrition on the central nervous system.

Purpose: Evidence shows diet promotes brain health. Combining foods and nutrients may have beneficial synergistic effects, but the effects on cognitive function interventions are inconsistent. So, a meta-analysis of RCTs was conducted to examine the specific effects on cognitive function.

Methods: We searched four databases from creation to April 2023. Eligible randomized controlled trials were identified. A random-effects meta-analysis was used to combine standardized mean differences (SMD) (95% confidence intervals [CI]), and homogeneity tests for a variance were calculated.

Results: A total of 19 studies involving 12,119 participants were included in this systematic review. The dietary intervention group had a positive effect on overall cognitive functioning compared to the control group (SMD = 0.14, 95% CI [0.08, 0.20], P < 0.00001). The dietary intervention improved executive function, processing speed and language skills (SMD = -0.10, 95% CI [-0.17,-0.04], P = 0.002, I² = 0%), (SMD = -0.16, 95% CI [-0.23,-0.09], P < 0.00001, I² = 0%), (SMD = 0.10, 95% CI [0.01, 0.20], P = 0.03, I² = 0%). The dietary intervention had no effect on delayed memory and spatial ability (SMD = 0.04, 95% CI [-0.02, 0.09], P = 0.20, I² = 0%), (SMD = 0.08, 95% CI [-0.01, 0.16], P = 0.08, I² = 0%).

Conclusion: The Mediterranean diet, a diet with restricted caloric intake, a diet incorporating aerobic exercise, a low-carbohydrate diet, and a healthy lifestyle diet (increased intake of fruits and vegetables, and weight and blood pressure management) appear to have positive effects on cognitively healthy adults, as reflected in their overall cognitive, processing speed, executive, and language functions.

Prospero registration number: CRD42023414704.

Objectives: Vitamin D deficiency has been associated with psychiatric disorders and behavioral phenotypes such as Attention-Deficit/Hyperactivity Disorder (ADHD). Considering that vitamin D levels are polygenic, we aim to evaluate the overall effects of its genetic architecture on symptoms of inattention, hyperactivity, and impulsivity and on the serum levels of vitamin D in two independent samples of adults, as well as the specific effects of five relevant polymorphisms in vitamin D-related genes.

Methods: We evaluated 870 subjects from an ADHD sample (407 cases and 463 controls) and 319 subjects from an academic community (nutrigenetic sample). Vitamin D serum levels were obtained through Elisa test and genetic data by TaqMan™ allelic discrimination and Infinium PsychArray-24 BeadChip genotyping. Polygenic Scores (PGS) were calculated on PRSice2 based on the latest GWAS for Vitamin D and statistical analyses were conducted at Plink and SPSS software.

Results: Vitamin D PGSs were associated with inattention in the ADHD sample and with hyperactivity when inattention symptoms were included as covariates. In the nutrigenetic sample, CYP2R1 rs10741657 and DHCR7 rs12785878 were nominally associated with impulsivity and hyperactivity, respectively, and both with vitamin D levels. In the clinical sample, RXRG rs2134095 was associated with impulsivity.

Discussion: Our findings suggest a shared genetic architecture between vitamin D levels and ADHD symptoms, as evidenced by the associations observed with PGS and specific genes related to vitamin D levels. Interestingly, differential effects for vitamin D PGS were found in inattention and hyperactivity, which should be considered in further studies involving ADHD.

Objectives: Observational studies suggested a potential correlation between dietary intake and amyotrophic lateral sclerosis (ALS), but conflicting findings exist and causality remains unclear. Here, we performed a Mendelian randomization (MR) analysis to evaluate the causal impact of relative intake of (i) carbohydrate, (ii) fat, and (iii) protein on ALS risk.

Methods: The genome-wide association summary statistics of three dietary macronutrient intake traits and ALS were obtained. Initially, forward and reverse univariable MR (UVMR) analysis were conducted using the inverse variance weighted (IVW) method as the primary approach, supplemented by MR-Egger, weighted median, and maximum likelihood. Subsequently, multivariable MR (MVMR) analysis was performed to assess the independent causal effects of each dietary. Additionally, diverse sensitivity tests were conducted to evaluate the reliability of the MR analyses.

Results: The forward UVMR analysis conducted by IVW indicated that relative carbohydrate intake significantly increased ALS risk. Furthermore, results from three other MR methods paralleled those from IVW. However, the other two dietary intake traits did not have a causative impact on ALS risk. The reverse UVMR analysis indicated that ALS did not causatively influence the three dietary intake traits. The MVMR analysis showed that after adjusting for the effects of the other two dietary intake traits, relative carbohydrate intake independently and significantly increased ALS risk. Sensitivity tests indicated no significant heterogeneity or horizontal pleiotropy.

Discussion: MR analysis supported relative carbohydrate independently increasing ALS risk. Nevertheless, further validation of this finding in future large cohorts is required.

Objectives: This study investigates the effect of dietary fiber on the prevention of depressive symptoms.

Methods: In a cohort of 88,826 Korean adults (57,284 men and 31,542 women), we longitudinally evaluated the risk of depressive symptoms according to quartiles of dietary fiber intake for 5.8 years of follow-up. A food frequency questionnaire was used in evaluating dietary fiber intake. Depressive symptoms were assessed by the Center for Epidemiological Studies-Depression (CES-D) scale, in which CES-D ≥ 16 was defined as depressive symptoms. The Cox proportional hazards model was used to calculate the adjusted hazard ratio (HR) and 95% confidence intervals (CI) for depressive symptoms (adjusted HR [95% CI]). Subgroup analysis was performed for gender and BMI (≥25 or <25).

Result: In men, the risk of depressive symptoms significantly decreased with the increase of dietary fiber (quartile 1: reference, quartile 2: 0.93 [0.87-0.99], quartile 3: 0.91 [0.85-0.98] and quartile 4: 0.84 [0.77-0.92]). This association was more prominently observed in men with BMI ≥ 25 (quartile 1: reference, quartile 2: 0.95 [0.86-1.06], quartile 3: 0.88 [0.79-0.99] and quartile 4: 0.84 [0.73-0.97]). Women did not show a significant association between quartile groups of dietary fiber intake and the risk of depressive symptoms across subgroup analysis for BMI.

Conclusion: High intake of dietary fiber is potentially effective in reducing depressive symptoms in Korean men. The protective effect of dietary fiber on depressive symptoms may vary by gender and obesity.