Folic acid deficiency and homocysteine impair DNA repair in hippocampal neurons and sensitize them to amyloid toxicity in experimental models of Alzheimer's disease

Neuroprotective effect of folic acid by maintaining DNA stability and mitochondrial homeostasis through the ATM/CHK2/P53/PGC-1α pathway in alcohol-exposed mice

Excessive drinking leads to alcoholic brain injury, which is characterized by neuroinflammation, cognitive decline and motor dysfunction. These pathological features are closely related to chromosomal DNA damage and mitochondrial dysfunction. In this study, we aimed to uncover the neuroprotective effects of folic acid (FA) in mice with alcoholic brain injury. C57BL/6J mice were used to establish the murine model of alcoholic brain injury after 12 weeks of alcohol exposure. FA treatment significantly increased the levels of ATP and mitochondrial DNA (mtDNA) copy number in brain tissues of alcohol-exposed mice, and regulated the imbalance of mitochondrial homeostasis in cortical nerve cells. Furthermore, it could reduce the leakage of mtDNA into the cytoplasm, thereby inhibiting the cGAS/STING/NLRP3 inflammatory pathway and alleviating neuroinflammation. In addition, FA treatment reduced DNA damage in peripheral blood lymphocytes and decreased the expression of 53BP1 and γ-H2AX proteins in brain tissues of alcohol-exposed mice. At the molecular level, FA reduced DNA damage by downregulating the ATM/CHK2/P53 pathway and induced the expression of peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), which further inversely enhanced mitochondrial function through positive feedback. Collectively, this study provides experimental evidence that FA protects DNA stability and mitochondrial homeostasis in alcohol-exposed mice by downregulating the ATM/CHK2/P53/PGC-1α signaling pathway.

Bibliometric analysis and description of research trends on nutritional management in Alzheimer's disease patients (1988-2024)

Background

Alzheimer's disease (AD) is a severe neurodegenerative disorder. Nutritional management has been recognized as a potential therapeutic approach to mitigate AD progression. This study aimed to analyze the bibliometric characteristics and research trends of publications on nutritional management in AD.

Methods

A systematic search was conducted on the Web of Science Core Collection database to identify publications related to nutritional management in AD from 1988 to 2024. Bibliometric analysis was performed using VOSviewers (V 1.6.20), CiteSpace (V 6.3.R1) and R 4.3.3.

Results

A total of 554 publications from 311 countries led by the USA were identified. The number of publications has increased annually. The most cited article discussed the role of diet in providing antioxidants to combat oxidative stress in neurodegenerative diseases. The University of California system published the most articles, and Rush University had the most international collaborations. These publications came from 3,298 authors, among which Mattson MP had the highest total publications and citations. The Journal of Alzheimer's Disease published the most articles and received the most citations. Keywords analysis revealed evolving trends, with early emphasis on "precursor protein" and later shifts to "dietary restriction," and more recently, "insulin resistance" and "synaptic plasticity." Emerging keywords include "obesity," "cognitive impairment" and "association."

Conclusion

This study represents the first summary of research trends in AD nutritional management. Future research is likely to focus on the associations between nutrition, insulin resistance, synaptic plasticity, and cognitive impairment in AD patients. This information provides valuable insights for scholars and practitioners in the field.

Risk of Dementia and Its Associated Factors Among the Patients With Coronary Artery Disease Attending a Tertiary Cardiac Hospital of Dhaka City: A Cross-Sectional Study

Background and Aims

In Bangladesh, data related to the future risk of dementia and its associated factors are scarce. Furthermore, no dementia risk prediction tool has yet been applied to estimate the risk in any population in Bangladesh. Therefore, our objective was to assess the risk of dementia and its associated factors among patients with coronary artery disease (CAD).

Methods

This cross-sectional study conveniently recruited 280 stable patients with CAD who were admitted for coronary revascularization at a tertiary cardiac hospital situated in Dhaka, Bangladesh. Data were collected face-to-face using a pretested questionnaire adapted from the WHO STEP-wise Approach to Surveillance (STEPS) of Noncommunicable Diseases Risk Factors questionnaire (Version 3.2). The questionnaire included background information (sociodemographic, comorbidity), behavioral and metabolic risk factors, physical and biochemical measurements. The next 20 years' risk of dementia was estimated using the "Cardiovascular Risk Factors, Aging, and Incidence of Dementia" score. The risk score, risk levels, and risk factors were presented descriptively. The associated factors of dementia risk were elucidated using hierarchical multiple regression analysis.

Results

The mean ( ± standard deviation) risk score for dementia was 6.26 ± 2.28. The predicted "at-risk" population was 63.6%. The prevalent risk factors were unhealthy diets (84.3%) presented by inadequate fruit/vegetable consumption (70%) and added salt intake (46.4%). In the final model of hierarchical multiple regression, the risk score showed a significant association with several risk factors: family history of diabetes (p = 0.03), alcohol intake (p = 0.03), current smoking (p = 0.03), estimated glomerular filtration rate (p = 0.001), and diastolic blood pressure (p = 0.02).

Conclusion

A substantial proportion of patients with CAD had a future risk of dementia which demands an urgent risk reduction strategy in Bangladesh. Future longitudinal studies may more precisely justify the current findings.

Dietary Strategies to Mitigate Alzheimer's Disease: Insights into Antioxidant Vitamin Intake and Supplementation with Microbiota-Gut-Brain Axis Cross-Talk

Alzheimer's disease (AD), which is characterized by deterioration in cognitive function and neuronal death, is the most prevalent age-related progressive neurodegenerative disease. Clinical and experimental research has revealed that gut microbiota dysbiosis may be present in AD patients. The changed gut microbiota affects brain function and behavior through several mechanisms, including tau phosphorylation and increased amyloid deposits, neuroinflammation, metabolic abnormalities, and persistent oxidative stress. The lack of effective treatments to halt or reverse the progression of this disease has prompted a search for non-pharmaceutical tools. Modulation of the gut microbiota may be a promising strategy in this regard. This review aims to determine whether specific dietary interventions, particularly antioxidant vitamins, either obtained from the diet or as supplements, may support the formation of beneficial microbiota in order to prevent AD development by contributing to the systemic reduction of chronic inflammation or by acting locally in the gut. Understanding their roles would be beneficial as it may have the potential to be used as a future therapy option for AD patients.

Hyperhomocysteinemia and Disease-Is 10 μmol/L a Suitable New Threshold Limit?

Hyperhomocysteinemia (HHcy) is a medical condition characterized by an abnormally high level of homocysteine (Hcy) in the blood. Homocysteine is a toxic sulfur-containing amino acid that is produced during the metabolism of methionine. Under normal circumstances, Hcy is recycled back to methionine via the remethylation pathway, through the action of various enzymes and vitamins, particularly folic acid (vitamin B9) and B12 used when intracellular methionine levels are low, thus restoring the necessary levels to correctly maintain active protein synthesis. A second pathway, used in cases of intracellular methionine excess, (the trans-sulfuration pathway) is the one that recycles Hcy into cysteine (a precursor of glutathione), first passing through cystathionine (via the enzyme cystathionine beta-synthase), a reaction that requires vitamin B6 in its active form. HHcy has been identified as a risk factor for a variety of disorders, including cardiovascular diseases, multiple sclerosis, diabetes, Alzheimer's and Parkinson's diseases, osteoporosis and cancer. However, it remains unclear whether the slightly elevated concentration of Hcy (Hcy 7-10 μmol/L) is a causative factor or simply a marker of these pathologies. In human plasma, the concentration of Hcy ([Hcy]) is classified as mild (15 to 30 μmol/L), moderate (30 to 100 μmol/L), and severe (greater than 100 μmol/L). Interestingly, many laboratories continue to consider 25 μmol/L as normal. This review seeks to examine the controversial literature regarding the normal range of HHcy and emphasizes that even a [Hcy] level of 10 μmol/L may contribute to the development of several diseases, aiming to discuss whether it would be appropriate to lower the threshold of HHcy normal values.

Exploring the association between number of teeth, food intake, and cognitive function: A 9-year longitudinal study

OBJECTIVES

This study aimed to investigate the association between the number of teeth, food intake, and cognitive function in Japanese community-dwelling older adults.

METHODS

This 9-year longitudinal study included a total of 293 analyzable participants who participated in baseline and follow-up surveys. Dental status (number of teeth and periodontal pocket depth), dietary assessment using the brief-type self-administered diet history questionnaire, cognitive function, and the following confounding factors were evaluated: educational level, financial satisfaction, living situation, smoking and drinking habits, history of chronic diseases, apolipoprotein E-ε4 carrier, body mass index, handgrip strength, instrumental activities of daily living, and depressive symptomatology. The Japanese version of the Montreal Cognitive Assessment was used to evaluate cognitive function. A multinomial logistic regression analysis for the intake level of each food categorized into three groups (low, moderate, high), and a generalized estimating equation (GEE) for cognitive function over nine years were performed.

RESULTS

After controlling for confounding factors, the number of teeth was shown to be associated with the intake of green-yellow vegetables and meat. Furthermore, the GEE indicated that the lowest quartile of intake of green-yellow vegetables significantly associated with lower cognitive function (unstandardized regression coefficient [B] = -0.96, 95 % confidence interval [CI]: -1.72 to -0.20), and the lowest quartile of intake of meat significantly associated with lower cognitive function (B = -1.42, 95 % CI: -2.27 to -0.58).

CONCLUSIONS

The intake of green and yellow vegetables and meat, which is influenced by the number of teeth, was associated with cognitive function in Japanese community-dwelling older adults.

CLINICAL SIGNIFICANCE

There are few studies that have examined the association between oral health, food intake, and cognitive function. This 9-year longitudinal study suggests that it is important to maintain natural teeth to enable the functional means to consume green-yellow vegetables and meat, and thereby help maintain cognitive function.

Exploring role of natural compounds in molecular alterations associated with brain ageing: A perspective towards nutrition for ageing brain

Aging refers to complete deterioration of physiological integrity and function. By midcentury, adults over 60 years of age and children under 15 years will begin to outnumber people in working age. This shift will bring multiple global challenges for economy, health, and society. Eventually, aging is a natural process playing a vital function in growth and development during pediatric stage, maturation during adult stage, and functional depletion. Tissues experience negative consequences with enhanced genomic instability, deregulated nutrient sensing, mitochondrial dysfunction, and decline in performance on cognitive tasks. As brain ages, its volume decreases, neurons & glia get inflamed, vasculature becomes less developed, blood pressure increases with a risk of stroke, ischemia, and cognitive deficits. Diminished cellular functions leads to progressive reduction in functional and emotional capacity with higher possibility of disease and finally death. This review overviews cellular as well as molecular aspects of aging, biological pathway related to accelerated brain aging, and strategies minimizing cognitive aging. Age-related changes include altered bioenergetics, decreased neuroplasticity and flexibility, aberrant neural activity, deregulated Ca2+ homeostasis in neurons, buildup of reactive oxygen species, and neuro-inflammation. Unprecedented progress has been achieved in recent studies, particularly in terms of how herbal or natural substances affect genetic pathways and biological functions that have been preserved through evolution. Herein, the present work provides an overview of ageing and age-related disorders and explore the molecular mechanisms that underlie therapeutic effects of herbal and natural chemicals on neuropathological signs of brain aging.

Serum folate and risk of disabling dementia: a community-based nested case-control study

PURPOSE

The aim of this study was to examine associations between serum folate levels and risk of disabling dementia that required care under the national insurance (disabling dementia).

METHODS

We performed a nested case-control study in a community-based cohort, the Circulatory Risk in Communities Study, involving 13,934 Japanese individuals aged 40-84 years at the baseline period of 1984-2005. Serum folate was measured in 578 cases of incident disabling dementia, and in 1,156 controls whose age (±1 years), sex, area of residence, and baseline year were matched with the cases. The diagnosis of disabling dementia was performed by attending physicians under the National Long-Term Care Insurance System in Japan. Conditional odds ratios of disabling dementia according to quintiles of serum folate were calculated using conditional logistic regression models.

RESULTS

After a 20.8-year follow-up, serum folate was inversely associated with risk of disabling dementia. The respective multivariable odds ratios (95% CIs) were 0.71 (0.51-0.99), 0.76 (0.54-1.06), 0.70 (0.49-1.00), and 0.62 (0.43-0.90) for persons with the second, third, fourth, and highest quintiles of serum folate as compared with the lowest quintile (P for trend = 0.03). A similar association was observed for dementia with or without stroke.

CONCLUSION

In this nested case-control study with a long follow-up, low serum folate levels were associated with an increased risk of disabling dementia among Japanese individuals.

Self-assembled poloxamer-legumin/vicilin nanoparticles for the nanoencapsulation and controlled release of folic acid

Plant-based food proteins are a promising choice for the preparation of nanoparticles (NPs) due to their high digestibility, low cost, and ability to interact with various compounds and nutrients. Moreover, nanoencapsulation offers a potential solution for protecting nutrients during processing and enhancing their bioavailability. This study aimed to develop and evaluate nanoparticles (NPs) based on legumin/vicilin (LV) proteins extracted from fava beans, with the goal of encapsulating and delivering a model nutraceutical compound, folic acid (FA). Specifically, NPs were self-assembled from LV proteins extracted from commercially available frozen fava beans using a pH-coacervation method with poloxamer 188 (P188) and chemically cross-linked with glutaraldehyde. Microscopy and spectroscopy studies were carried out on the empty and FA-loaded NPs in order to evaluate the particle morphology, size, size distribution, composition, mechanism of formation, impact of FA loading and release behavior. In vitro studies with Caco-2 cells also confirmed that the empty and FA-loaded nanoparticles were non-toxic. Thus, the LV-NPs are good candidates as food additives for the delivery and stabilization of nutrients as well as in drug delivery for the controlled release of therapeutics.

Deficiencies in one-carbon metabolism led to increased neurological disease risk and worse outcome: homocysteine is a marker of disease state

Elevated plasma homocysteine levels have been identified as a significant, independent risk factor for the development of cognitive decline including Alzheimer's disease. While several studies have explored the link between homocysteine and disease risk, the associations have not been entirely clear. Elevated levels of homocysteine serve as a disease marker and understanding the underlying cause of these increased levels (e.g., dietary or genetic deficiency in one-carbon metabolism, 1C) will provide valuable insights into neurological disease risk and outcomes. Previous cell culture experiments investigating the mechanisms involved used ultra-high levels of homocysteine that are not observed in human patients. These studies have demonstrated the negative impacts of ultra-high levels of homocysteine can have on for example proliferation of neuroprogenitor cells in the adult hippocampus, as well as triggering neuronal apoptosis through a series of events, including DNA damage, PARP activation, NAD depletion, mitochondrial dysfunction, and oxidative stress. The aim of this mini-review article will summarize the literature on deficiencies in 1C and how they contribute to disease risk and outcomes and that homocysteine is a marker of disease.

Mendelian randomization to evaluate the effect of folic acid supplement on the risk of Alzheimer disease

We conducted a study to evaluate the impact of folic acid supplementation on the risk of Alzheimer disease (AD). A Mendelian randomization (MR) analysis model assessed the causal effects of folic acid supplementation on AD, utilizing data from recent genome-wide association studies. Effect estimates were scrutinized using various methods: inverse-variance weighted (IVW), simple mode, weighted mode, simple median, weighted median, penalized weighted median, and the MR-Egger method. The sensitivity analysis assessed heterogeneity and pleiotropy of individual single nucleotide polymorphisms (SNPs) using the IVW method with Cochran Q statistics and MR Egger intercept, respectively. Additionally, a leave-one-out sensitivity analysis determined potential SNP-driven associations. Both fixed-effect and random-effect IVW models in the MR analysis revealed a reduced risk of AD associated with folic acid supplementation (odds ratio, 0.930; 95% CI, 0.903-0.958, P < .001; odds ratio, 0.930; 95% CI, 0.910-0.950, P < .001) based on 7 SNPs as instrumental variables. The reverse MR analysis indicated no causal association between AD and folic acid supplementation. This study, utilizing genetic data, suggests that folic acid supplementation may potentially reduce the risk of AD and provides novel insights into its etiology and preventive measures.

Silent Infections are not So Silent: The Emerging Role of Combined Infections, Inflammation, and Vitamin Levels in OCD

Objective

Recent evidence highlights that different agents may trigger immune-mediated processes involved in the pathophysiology of different neuropsychiatric conditions. Given the limited information on obsessive-compulsive disorder (OCD), the present study aimed at assessing current/past infections and plasma levels of vitamin D, vitamin B12, folic acid, homocysteine and common peripheral inflammatory markers in a group of OCD outpatients.

Method

The sample included 217 adult outpatients with an OCD diagnosis according to the DSM-5 criteria. The Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) was used to assess the clinical phenotype and symptom severity. Laboratory blood tests measured levels of vitamin D, vitamin B12, folic acid, homocysteine, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), blood count and antibodies titers for cytomegalovirus (CMV), Epstein Barr virus (EBV), Toxoplasma gondii and antistreptolysin titer.

Results

Sixty-one patients had a previous EBV infection, 46 were seropositive for CMV IgG, 24 showed positive antistreptolysin titer, 14 were seropositive for Toxoplasma gondii IgG, and four for CMV IgM. More than a half of patients showed vitamin D insufficiency. Compared to seronegative patients, patients with a past EBV infection displayed significantly higher scores on the Y-BOCS total score and compulsion subscale, and other symptoms. Vitamin D was negatively correlated with both the Y-BOCS total score and the subscales scores. Folic acid was negatively correlated with the Y-BOCS total and obsessions subscale score.

Conclusions

The findings of our study show an association between Epstein-Barr infection and hypovitaminosis D and the overall severity and specific symptom patterns of OCD. The laboratory measures used in this study are useful, cheap and easy parameters that should be routinely assessed in patients with OCD. Further studies are needed to clarify their role in OCD pathophysiology and outcomes, as well as the potential therapeutic impact of vitamins and antibiotics/immunomodulatory agents in OCD and other psychiatric conditions.

Association between dietary niacin intake and cognitive function in the elderly: Evidence from NHANES 2011-2014

Recent studies have shown an inconsistent association between dietary niacin and cognitive function. And this remains unclear in the American outpatient population. The aim of this study was to assess whether there is an association between dietary niacin and cognitive performance in an older American population aged ≥60 years. A total of 2523 participants from the National Health and Nutrition Examination Survey (NHANES) 2011-2014 were enrolled. Cognitive function was assessed by the CERAD Word Learning (CERAD-WL) test, the CERAD Delayed Recall (CERAD-DR) test, the Animal Fluency test (AFT), and the Digit Symbol Substitution test (DSST). Cognitive impairment that meets one of the four scoring conditions listed above is defined as low cognitive function. Dietary niacin intake was obtained from 2 days of a 24-h recall questionnaire. Based on the quartiles of dietary niacin intake, they were divided into four groups: Q1 (<15.51 mg), Q2 (15.51-20.68 mg), Q3 (20.69-26.90 mg), and Q4 (>26.91 mg). The stability of the results was assessed using multifactorial logistic regression, restricted cubic spline (RCS) models, and sensitivity stratified analysis. More than half of the participants had cognitive impairment (52.52%). In the fully adjusted model, niacin was associated with a significantly reduced risk of cognitive impairment in Q3 and Q4 compared with the Q1 group (OR: 0.610, 95% CI: 0.403, 0.921, p = .022; OR: 0.592, 95% CI: 0.367, 0.954, p = .034). Meanwhile, niacin was negatively associated with poor cognition as assessed by the CERAD-WL test, CERAD test, AFT, and DSST. An L-shaped dose-response relationship between dietary niacin and cognitive function was observed in all participants (nonlinear p < .001). There were also interactions that existed in populations with different carbohydrate intakes and cholesterol intakes (p for interaction = .031, p for interaction = .005). These findings provide new evidence for the potential role of dietary niacin intake on cognitive function in the elderly.

Dietary patterns and the risk of Alzheimer's disease in an elderly Iranian population: a case-control study

BACKGROUND

An increasing number of studies in Western countries have shown that healthy eating patterns have a protective effect against cognitive decline and dementia, however, information about this relationship among non-western populations with different cultural environments is scarce. The present study investigated the association between dietary patterns (DPs) and cognitive function in the Iranian elderly.

METHODS

In this case-control study, the data of 290 elderly people in two groups of case and control (Mean age in case: 74.2 ± 8.6, in control: 67.3 ± 7.3 year) were analyzed. Two DPs of healthy and unhealthy were extracted from a 142-item dish-based food frequency questionnaire, and patterns driven by principal components analysis (PCA) of 25 food groups. Multivariate binary logistic regression calculated the odds ratio (OR) of cognitive impairment with adjustment for potential confounding factors.

RESULTS

A healthy DP, characterized by high consumption of fruits and vegetables, legumes, and nuts, was related to a decrease in the odds of Alzheimer's disease in Iranian elderly people. Also, moderate adherence to an unhealthy food pattern was associated with an increase in the probability of the disease; however, the association was not statistically significant.

CONCLUSION

In this elderly population, a healthy eating pattern was associated with reducing the risk of Alzheimer's disease. Further prospective studies are recommended.

Dietary folate intake and its association with longitudinal changes in cognition function

BACKGROUND & AIMS

Folate (vitamin B9) is an essential co-factor for one-carbon metabolism. Controversial evidence has emerged regarding the association between folate and cognitive performance. The aim of the study was to investigate the association between baseline dietary folate intake and cognitive decline in a population exposed to mandatory fortification during a median follow-up of 8 years.

METHODS

Multicenter, prospective cohort study involving 15,105 public servants aged 35-74 years old, both sexes, from The Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). Baseline dietary intake was assessed by a Food Frequency Questionnaire (FFQ). Six cognitive tests were performed in the three waves to assess memory, executive function and global cognition. Linear mixed-effects models were used to assess the association between dietary folate intake at baseline and changes in cognition over time.

RESULTS

Data from 11,276 participants were analyzed. The mean (SD) age was 51.7 (9) years, 50% were women, 63% were overweight/obese, and 56% had graduated from college or more. Overall dietary folate intake was not associated with cognitive decline; neither vitamin B12 intake was a modifier of this association. General dietary supplements and specifically multivitamins use did not affect these findings. Natural food folate group was associated with a slower rate of global cognitive decline (β (95% CI): 0.001 (0.000; 0.002), P = 0.015). There was no association between fortified food group and cognition scores.

CONCLUSION

Overall dietary folate intake was not associated with cognitive function in this Brazilian population. However, folate naturally occurring in food sources may slow global cognitive decline.

A bibliometric review on vitamins and Alzheimer's disease between 1996 and 2023

Objective

Alzheimer's disease (AD) is a major disease that affects the elderly worldwide. Several studies have revealed that vitamins may influence the risk of developing AD. However, information in this field remains ambiguous. Therefore, this study aimed to examine the relationship between AD and vitamins, identify journal publications and collaborators, and analyze keywords and research trends using a bibliometric method.

Methods

We systematically searched the Web of Science (WOS) Core Collection for papers published on AD and vitamins. Retrieved data regarding institutions, journals, countries, authors, journal distribution, keywords, and so on. SPSS 25 software was used for the statistical analysis, and CiteSpace V.6.1.R6 was used to visualize the information through collaborative networks.

Results

A total of 2,838 publications were ultimately included in accordance with the specified inclusion criteria. The number of publications gradually increased from 1996 to 2023, with papers published in 87 countries/regions and 329 institutions. China (centrality: 0.02) and the University of Kentucky (centrality: 0.09) were the major research countries and institutions, respectively. NEUROLOGY was cited most frequently, reaching 1,573, and had the greatest impact. The cited keywords show that "Alzheimer's disease," "oxidative stress," "vitamin E," and "dementia" have been research hotspots in recent years. Beta-carotene emerged in 2023 and was identified as a developmental trend in this field.

Conclusion

This is the first bibliometric analysis of vitamins associated with AD. We identified 2,838 articles in the field of vitamins and AD, analyzed the information of major countries/regions, institutions, and core journals in this field, and summarized the research hotspots and frontiers. These findings provide useful information for researchers to explore the role of vitamins in AD further.

The Effects of Methylfolate on Cognitive Decline and Dementia: A Protocol for Systematic Review and Meta-Analysis

INTRODUCTION

Dementia and cognitive decline are highly prevalent in later life and are growing public health concerns worldwide due to the increasing aging population. Individuals diagnosed with dementia have reduced mental function, resulting in social and cognitive skill deficits, increased dependence, and reduced autonomy-all of which are conditions associated with higher mortality rates. This systematic review aims to assess the effectiveness of treating dementia and cognitive decline with methylfolate. The main outcomes analyzed will be dementia and changes in cognitive function measured by different instruments in older adults treated with methylfolate. Secondary outcomes, such as inflammatory markers, plasma folic-acid levels, and total homocysteine, will also be assessed.

METHODS AND ANALYSIS

This study will be carried out in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. This protocol is registered in the International Prospective Registry of Systematic Reviews, under the code CRD42021275755. We will include clinical trials conducted with older adults diagnosed with dementia or cognitive decline and treated with folic acid. The searches will be conducted on the PubMed, Scopus, and Embase databases, and the articles will be selected by reading their titles and abstracts first, followed by the full text. The quality of the selected studies will be assessed using GRADE and the risk of bias will be assessed using the Downs-and-Black method.

ETHICS AND DISSEMINATION

The results will be presented at scientific conferences and disseminated by publishing a scientific article in an international English-language journal. We hope to find robust and significant evidence regarding the effectiveness of methylfolate supplementation in improving dementia symptoms and cognitive decline among older adults. By systematizing this evidence and possibly performing a meta-analysis study, we expect to significantly contribute to the treatment of this health problem, reduce mortality, and improve the quality of life and health of this population, boosting the development of medical protocols capable of reducing the financial effects of public health.

Herbal/Natural Compounds Resist Hallmarks of Brain Aging: From Molecular Mechanisms to Therapeutic Strategies

Aging is a complex process of impaired physiological integrity and function, and is associated with increased risk of cardiovascular disease, diabetes, neurodegeneration, and cancer. The cellular environment of the aging brain exhibits perturbed bioenergetics, impaired adaptive neuroplasticity and flexibility, abnormal neuronal network activity, dysregulated neuronal Ca²⁺ homeostasis, accumulation of oxidatively modified molecules and organelles, and clear signs of inflammation. These changes make the aging brain susceptible to age-related diseases, such as Alzheimer's and Parkinson's diseases. In recent years, unprecedented advances have been made in the study of aging, especially the effects of herbal/natural compounds on evolutionarily conserved genetic pathways and biological processes. Here, we provide a comprehensive review of the aging process and age-related diseases, and we discuss the molecular mechanisms underlying the therapeutic properties of herbal/natural compounds against the hallmarks of brain aging.

Two Faces of Catechol-O-Methyltransferase Inhibitor on One-Carbon Metabolism in Parkinson's Disease: A Meta-Analysis

Levodopa (L-dopa) and catechol-O-methyltransferase (COMT) inhibition are widely used therapeutics in Parkinson's disease (PD). Despite their therapeutic effects, it was raised that nutrients involved in one-carbon metabolism can be deteriorated by PD therapies. The aim of this meta-analysis was to investigate the impact of L-dopa and COMT inhibitors on levels of homocysteine (Hcy), vitamin B₁₂ and folate in patients with PD. A total of 35 case-control studies from 14 different countries were selected through PubMed, MEDLINE and Google Scholar and were meta-analyzed. In the L-dopa group, the Hcy level was higher compared to the PD without L-dopa group (SMD: 5.11 μmol/L, 95% CI: 3.56 to 6.66). Moreover, vitamin B₁₂ and folate levels in the L-dopa group were lower compared to the healthy control (SMD: -62.67 pg/mL, 95% CI: -86.53 to -38.81; SMD: -0.89 ng/mL, 95% CI: -1.44 to -0.33, respectively). The COMT inhibitor group showed lower levels of Hcy (SMD: -3.78 μmol/L, 95% CI: -5.27 to -2.29) and vitamin B₁₂ (SMD: -51.01 pg/mL, 95% CI: -91.45 to -10.57), but higher folate levels (SMD: 1.78 ng/mL, 95% CI: -0.59 to 4.15) compared to the L-dopa group. COMT inhibitors may ameliorate L-dopa-induced hyper-homocysteine and folate deficiency but exacerbate vitamin B₁₂ deficiency.

Homocysteine - A predictor for five year-mortality in patients with subjective cognitive decline, mild cognitive impairment and Alzheimer's dementia

BACKGROUND

Subjective Cognitive Decline (SCD) and Mild Cognitive Impairment (MCI) are preclinical stages of Alzheimer's Disease (AD), which is the most common entity of dementia. Homocysteine is an amino acid in the methionine cycle, and many studies revealed a significant association between elevated homocysteine serum levels and the progression of dementia. The primary objective of this retrospective study was to investigate whether elevated homocysteine serum levels could be associated with mortality and neuropsychological test results in individuals suffering from SCD, MCI or AD.

METHODS

This study is a single-center explorative retrospective data analysis with 976 data protocols from the Memory Outpatient's Clinic of the Medical University of Vienna included. All patients underwent a neurological examination, a laboratory blood test, and neuropsychological testing to establish a diagnosis of either SCD, MCI, or AD. Data was evaluated by Kaplan-Meier functions, factor analysis, and binary logistic regression models.

RESULTS

Patients with AD showed significantly higher mean homocysteine levels (SCD 12.15 ± 4.71, MCI 12.80 ± 4.81, AD 15.0 ± 6.44 μmol/L) compared to those with SCD and MCI (p ≤ .001). The mean age of patients with AD (75.2 ± 7.8) was significantly older at the time of testing than of patients with MCI (69.1 ± 9.6) or SCD (66.8 ± 9.3). Since homocysteine levels increase with age, this could be a possible explanation for the higher levels of AD patients. The age at death did not differ significantly between all diagnostic subgroups, resulting in the shortest survival times for AD patients. Homocysteine levels were negatively associated with in Mini-Mental State Examination (MMSE) and Neuropsyhcological Test Battery Vienna (NTBV) factors F1-F4 (F1 = attention, F2 = memory, F3 = executive functions, F4 = naming/verbal comprehension). Moreover, higher homocysteine levels significantly predicted shorter five-year survival in the logistic regression models, even after adjusting for age, diagnostic subgroups, sex, years of education and results of neuropsychological testing.

CONCLUSION

The results of this study suggest that homocysteine levels are independently associated with impaired cognitive function and increased five-year mortality.

A Review on Phyto-Therapeutic Approaches in Alzheimer's Disease

Neurodegenerative diseases occur due to progressive and sometimes irreversible loss of function and death of nerve cells. A great deal of effort is being made to understand the pathogenesis of neurodegenerative diseases. In particular, the prevalence of Alzheimer's disease (AD) is quite high, and only symptomatic therapy is available due to the absence of radical treatment. The aim of this review is to try to elucidate the general pathogenesis of AD, to provide information about the limit points of symptomatic treatment approaches, and to emphasize the potential neurologic effects of phytocompounds as new tools as therapeutic agents for disease prevention, retardation, and therapy. This survey also covers the notable properties of herbal compounds such as their effects on the inhibition of an enzyme called acetylcholinesterase, which has significant value in the treatment of AD. It has been proven that phytopharmaceuticals have long-term effects that could protect nervous system health, eliminate inflammatory responses, improve cognitive damage, provide anti-aging effects in the natural aging process, and alleviate dementia sequelae. Herbal-based therapeutic agents can afford many advantages and can be used as potentially as new-generation therapeutics or complementary agents with high compliance, fewer adverse effects, and lower cost in comparison to the traditional pharmaceutical agents in the fight against AD.

Plasma lipid profiles and homocysteine levels in anti-N-methyl-D-aspartate receptor encephalitis

Introduction

We aimed to investigate whether lipid profiles and homocysteine levels in patients with anti-N-methyl-D-aspartate receptor encephalitis are related to clinical presentation and prognosis, which may contribute to further research on the pathogenesis and treatment of this disease.

Methods

This study included a total of 43 patients with anti-N-methyl-D-aspartate receptor encephalitis and 43 sex-age-matched healthy controls. Baseline demography, clinical data, patient outcomes, and ancillary examination results were recorded. Patients were followed up every 2-3 months during the first year. The modified Rankin Scale score was used to evaluate the therapeutic effect and clinical outcome.

Results

Among the 43 patients included in this study, 55.81% were male, the mean age of onset was 27 years old, and the median modified Rankin Scale score on admission was 3.0. Apolipoprotein A-1 was significantly lower in patients with anti-N-methyl-D-aspartate receptor encephalitis compared with healthy controls (p = 0.004). Compared with healthy controls, homocysteine (p = 0.002), apolipoprotein B (p = 0.004), Lpa (p = 0.045), and apolipoprotein B/apolipoprotein A-1 (p = 0.001) were significantly increased in patients with anti-N-methyl-D-aspartate receptor encephalitis. According to the modified Rankin Scale scores, 6 months after discharge, 72.09% of patients had a good prognosis and 27.91% had a poor prognosis. In the good prognosis group, age (p = 0.031), lipoprotein a (p = 0.023), apolipoprotein A-1 (p = 0.027) at baseline, and the modified Rankin Scale score on admission (p = 0.019) were significantly higher than those in the poor prognosis group.

Conclusion

This study suggests the possibility that serum lipid profile and homocysteine play an important role in the pathogenesis of anti-N-methyl-D-aspartate receptor encephalitis, providing support for lipid-lowering treatment of anti-N-methyl-D-aspartate receptor encephalitis patients.

Resolving Geroplasticity to the Balance of Rejuvenins and Geriatrins

According to the cell centric hypotheses, the deficits that drive aging occur within cells by age dependent progressive damage to organelles, telomeres, biologic signaling pathways, bioinformational molecules, and by exhaustion of stem cells. Here, we amend these hypotheses and propose an eco-centric model for geroplasticity (aging plasticity including aging reversal). According to this model, youth and aging are plastic and require constant maintenance, and, respectively, engage a host of endogenous rejuvenating (rejuvenins) and gero-inducing [geriatrin] factors. Aging in this model is akin to atrophy that occurs as a result of damage or withdrawal of trophic factors. Rejuvenins maintain and geriatrins adversely impact cellular homeostasis, cell fitness, and proliferation, stem cell pools, damage response and repair. Rejuvenins reduce and geriatrins increase the age-related disorders, inflammatory signaling, and senescence and adjust the epigenetic clock. When viewed through this perspective, aging can be successfully reversed by supplementation with rejuvenins and by reducing the levels of geriatrins.

The Functional Characteristics of Goat Cheese Microbiota from a One-Health Perspective

Goat cheese is an important element of the Mediterranean diet, appreciated for its health-promoting features and unique taste. A pivotal role in the development of these characteristics is attributed to the microbiota and its continuous remodeling over space and time. Nevertheless, no thorough study of the cheese-associated microbiota using two metaomics approaches has previously been conducted. Here, we employed 16S rRNA gene sequencing and metaproteomics to explore the microbiota of a typical raw goat milk cheese at various ripening timepoints and depths of the cheese wheel. The 16S rRNA gene-sequencing and metaproteomics results described a stable microbiota ecology across the selected ripening timepoints, providing evidence for the microbiologically driven fermentation of goat milk products. The important features of the microbiota harbored on the surface and in the core of the cheese mass were highlighted in both compositional and functional terms. We observed the rind microbiota struggling to maintain the biosafety of the cheese through competition mechanisms and/or by preventing the colonization of the cheese by pathobionts of animal or environmental origin. The core microbiota was focused on other biochemical processes, supporting its role in the development of both the health benefits and the pleasant gustatory nuances of goat cheese.

Interactions between folate intake and genetic predictors of gene expression levels associated with colorectal cancer risk

Observational studies have shown higher folate consumption to be associated with lower risk of colorectal cancer (CRC). Understanding whether and how genetic risk factors interact with folate could further elucidate the underlying mechanism. Aggregating functionally relevant genetic variants in set-based variant testing has higher power to detect gene-environment (G × E) interactions and may provide information on the underlying biological pathway. We investigated interactions between folate consumption and predicted gene expression on colorectal cancer risk across the genome. We used variant weights from the PrediXcan models of colon tissue-specific gene expression as a priori variant information for a set-based G × E approach. We harmonized total folate intake (mcg/day) based on dietary intake and supplemental use across cohort and case-control studies and calculated sex and study specific quantiles. Analyses were performed using a mixed effects score tests for interactions between folate and genetically predicted expression of 4839 genes with available genetically predicted expression. We pooled results across 23 studies for a total of 13,498 cases with colorectal tumors and 13,918 controls of European ancestry. We used a false discovery rate of 0.2 to identify genes with suggestive evidence of an interaction. We found suggestive evidence of interaction with folate intake on CRC risk for genes including glutathione S-Transferase Alpha 1 (GSTA1; p = 4.3E-4), Tonsuko Like, DNA Repair Protein (TONSL; p = 4.3E-4), and Aspartylglucosaminidase (AGA: p = 4.5E-4). We identified three genes involved in preventing or repairing DNA damage that may interact with folate consumption to alter CRC risk. Glutathione is an antioxidant, preventing cellular damage and is a downstream metabolite of homocysteine and metabolized by GSTA1. TONSL is part of a complex that functions in the recovery of double strand breaks and AGA plays a role in lysosomal breakdown of glycoprotein.

B vitamin intakes modify the association between particulate air pollutants and incidence of all-cause dementia: Findings from the Women's Health Initiative Memory Study

INTRODUCTION

Particulate air pollutants may induce neurotoxicity by increasing homocysteine levels, which can be lowered by high B vitamin intakes. Therefore, we examined whether intakes of three B vitamins (folate, B12 , and B6 ) modified the association between PM2.5 exposure and incidence of all-cause dementia.

METHODS

This study included 7183 women aged 65 to 80 years at baseline. B vitamin intakes from diet and supplements were estimated by food frequency questionnaires at baseline. The 3-year average PM2.5 exposure was estimated using a spatiotemporal model.

RESULTS

During a mean follow-up of 9 years, 342 participants developed all-cause dementia. We found that residing in locations with PM2.5 exposure above the regulatory standard (12 μg/m3 ) was associated with a higher risk of dementia only among participants with lower intakes of these B vitamins.

DISCUSSION

This is the first study suggesting that the putative neurotoxicity of PM2.5 exposure may be attenuated by high B vitamin intakes.

Homocysteine, Cognitive Functions, and Degenerative Dementias: State of the Art

There is strong evidence that homocysteine is a risk factor not only for cerebrovascular diseases but also for degenerative dementias. A recent consensus statement renewed the importance and the role of high levels of homocysteine in cognitive decline in several forms of degenerative dementia, such as Alzheimer's disease. Although the molecular mechanisms by which homocysteine causes cell dysfunction are known, both the impact of homocysteine on specific cognitive functions and the relationship between homocysteine level and non-Alzheimer dementias have been poorly investigated. Most of the studies addressing the impact of hyperhomocysteinemia on dementias have not examined the profile of performance across different cognitive domains, and have only relied on screening tests, which provide a very general and coarse-grained picture of the cognitive status of the patients. Yet, trying to understand whether hyperhomocysteinemia is associated with the impairment of specific cognitive functions would be crucial, as it would be, in parallel, learning whether some brain circuits are particularly susceptible to the damage caused by hyperhomocysteinemia. These steps would allow one to (i) understand the actual role of homocysteine in the pathogenesis of cognitive decline and (ii) improve the diagnostic accuracy, differential diagnosis and prognostic implications. This review is aimed at exploring and revising the state of the art of these two strictly related domains. Suggestions for future research are provided.

Effectiveness and acceptability of non-pharmacological interventions in people with mild cognitive impairment: Overview of systematic reviews and network meta-analysis

BACKGROUND

To explore effectiveness and acceptability of non-pharmacological interventions in mild cognitive impairment (MCI).

METHODS

Overview of systematic reviews and network meta-analysis were conducted. Systematic reviews (SRs) were searched via seven databases from June 2015 to June 2020. Randomized controlled trials (RCTs) were retrieved. The Methodological quality was assessed by AMSTAR 2 and RoB 2. Outcomes were effectiveness and acceptability measured by standardized mean differences (SMDs) and odd ratios (ORs) with 95% confidence interval (CI). Pairwise meta-analysis was first conducted, followed by network meta-analysis.

RESULTS

A total of 22 SRs and 42 RCTs with 4401 participants were included. The methodological quality of included SRs and RCTs were moderate. There were four interventions, with three types of physical activity (aerobic, muscle-strengthening, and mind-body), three types of cognitive (rehearsal-based, compensatory, and mixed), multicomponent (physical and cognitive component), and nutrition intervention. No significant inconsistency was identified. Regarding intervention effectiveness, muscle-strengthening (SMDs 0.87, 95% CI 0.31-1.43; rank 1), mind-body (0.76, 0.38-1.14; rank 2) and aerobic (0.34, 0.13-0.50; rank 3) were significantly better than the control group and there was no significant difference among these types of intervention . Cognitive intervention of rehearsal-based (1.33, 0.30-2.35; rank 1) and mixed (0.55, 0.00-1.11; rank 2) were significantly better than the control group and there was no significant difference among these types of intervention. Multicomponent intervention (0.32, 0.02-0.62) were significantly better than the control group but not better than the single component group. Regarding acceptability, there was no significant difference among types of intervention.

CONCLUSION

Physical activity, cognitive, and multicomponent intervention could be provided regardless of their types and acceptability due to their effectiveness on improved cognitive function for people with MCI.

Is There a Connection between the Metabolism of Copper, Sulfur, and Molybdenum in Alzheimer’s Disease? New Insights on Disease Etiology

Alzheimer’s disease (AD) and other forms of dementia was ranked 3rd in both the Americas and Europe in 2019 in a World Health Organization (WHO) publication listing the leading causes of death and disability worldwide. Copper (Cu) imbalance has been reported in AD and increasing evidence suggests metal imbalance, including molybdenum (Mo), as a potential link with AD occurrence.We conducted an extensive literature review of the last 60 years of research on AD and its relationship with Cu, sulfur (S), and Mo at out of range levels.Weanalyzed the interactions among metallic elements’ metabolisms;Cu and Mo are biological antagonists, Mo is a sulfite oxidase and xanthine oxidase co-factor, and their low activities impair S metabolism and reduce uric acid, respectively. We found significant evidence in the literature of a new potential mechanism linking Cu imbalance to Mo and S abnormalities in AD etiology: under certain circumstances, the accumulation of Cu not bound to ceruloplasmin might affect the transport of Mo outside the blood vessels, causing a mild Mo deficiency that might lowerthe activity of Mo and S enzymes essential for neuronal activity. The current review provides an updated discussion of the plausible mechanisms combining Cu, S, and Mo alterations in AD.

Biophysical and modeling-based approach for the identification of inhibitors against DOHH from Leishmania donovani

The amino acid hypusine (Nε-4-amino-2-hydroxybutyl(lysine)) occurs only in isoforms of eukaryotic translation factor 5A (eIF5A) and has a role in initiating protein translation. Hypusinated eIF5A promotes translation and modulates mitochondrial function and oxygen consumption rates. The hypusination of eIF5A involves two enzymes, deoxyhypusine synthase and deoxyhypusine hydroxylase (DOHH). DOHH is the second enzyme that completes the synthesis of hypusine and the maturation of eIF5A. Our current study aims to identify inhibitors against DOHH from Leishmania donovani (LdDOHH), an intracellular protozoan parasite causing Leishmaniasis in humans. The LdDOHH protein was produced heterologously in Escherichia coli BL21(DE3) cells and characterized biochemically. The three-dimensional structure was predicted, and the compounds folic acid, scutellarin and homoarbutin were selected as top hits in virtual screening. These compounds were observed to bind in the active site of LdDOHH stabilizing the structure by making hydrogen bonds in the active site, as observed by the docking and molecular dynamics simulation studies. These results pave the path for further investigation of these molecules for their anti-leishmanial activities.

Reversal of Lipid Metabolism Dysregulation by Selenium and Folic Acid Co-Supplementation to Mitigate Pathology in Alzheimer’s Disease

Aberrant lipid metabolism is reported to be closely related to the pathogenesis of neurodegenerative diseases, such as Alzheimer’s disease (AD). Selenium (Se) and folate are two ideal and safe nutritional supplements, whose biological effects include regulating redox and homocysteine (Hcy) homeostasis in vivo. Here, to achieve effective multitarget therapy for AD, we combined Se and folic acid in a co-supplementation regimen (Se-FA) to study the therapeutic potential and exact mechanism in two transgenic mouse models of AD (APP/Tau/PSEN and APP/PS1). In addition to a reduction in Aβ generation and tau hyperphosphorylation, a restoration of synaptic plasticity and cognitive ability was observed in AD mice upon Se-FA administration. Importantly, by using untargeted metabolomics, we found that these improvements were dependent on the modulation of brain lipid metabolism, which may be associated with an antioxidant effect and the promotion of Hcy metabolism. Thus, from mechanism to effects, this study systematically investigated Se-FA as an intervention for AD, providing important mechanistic insights to inform its potential use in clinical trials.

Epigenetic Changes and Its Intervention in Age-Related Neurodegenerative Diseases

Epigenetic mechanisms involving the modulation of gene activity without modifying the DNA bases are reported to have lifelong effects on mature neurons in addition to their impact on synaptic plasticity and cognition. Histone methylation and acetylation are involved in synchronizing gene expression and protein function in neuronal cells. Studies have demonstrated in experimental models of neurodegenerative disorders that manipulations of these two mechanisms influence the susceptibility of neurons to degeneration and apoptosis. In Alzheimer's disease (AD), the expression of presenilin 1 (PSEN1) is markedly increased due to decreased methylation at CpG sites, thus promoting the accumulation of toxic amyloid-β (Aβ) peptide. In Parkinson's disease (PD), dysregulation of α-synuclein (SNCA) expression is presumed to occur via aberrant methylation at CpG sites, which controls the activation or suppression of protein expression. Mutant Huntingtin (mtHTT) alters the activity of histone acetyltransferases (HATs), causing the dysregulation of transcription observed in most Huntington's disease (HD) cases. Folate, vitamin B6, vitamin B12, and S-adenosylmethionine (SAM) are vital cofactors involved in DNA methylation modification; 5-azacytidine (AZA) is the most widely studied DNA methyltransferase (DNMT) inhibitor, and dietary polyphenols are DNMT inhibitors in vitro. Drug intervention is believed to reverse the epigenetic mechanisms to serve as a regulator in neuronal diseases. Nevertheless, the biochemical effect of the drugs on brain function and the underlying mechanisms are not well understood. This review focuses on further discussion of therapeutic targets, emphasizing the potential role of epigenetic factors including histone and DNA modifications in the diseases.

Plasma folate levels in relation to cognitive impairment: a community-based cohort of older adults in China

PURPOSE

Lower plasma level of folate has been associated with an increased risk of age-related cognitive impairment. However, studies that examined this relation have yielded mixed results. We aimed to examine the prospective association of plasma folate level with risk of cognitive impairment in a community-based prospective cohort of older adults in China.

METHODS

This study included 615 participants (mean age: 76.3 years) without baseline cognitive impairment from the Rugao Longevity and Ageing Study (RuLAS). We used logistic regression to examine the prospective association between baseline plasma folate and risk of cognitive impairment in the next two years. Fasting blood samples were collected and assayed for plasma folate level at baseline. Cognitive impairment was defined as Hasegawa Dementia Scale (HDS) score ≤ 21.5 points.

RESULTS

During two years' follow-up, 20.7% of the participants developed cognitive impairment. After controlled for age, gender, and plasma homocysteine, a higher level of plasma folate was associated with lower odds of cognitive impairment. The corresponding odds ratio (OR) with 95% confidence interval was 0.41 (0.19-0.89) comparing participants at extreme quintiles of plasma folate (median level 17.2 vs. 6.3 nmol/L). The associations were similar after further adjustment for major demographic and lifestyle factors (OR = 0.42, 0.18-0.98). Moreover, the inverse association was particularly stronger among males (OR = 0.12, 0.03-0.52) but was non-significant among females.

CONCLUSION

Our findings support a potential beneficial role of higher plasma folate levels in cognitive function in older Chinese adults, particularly among males. Future studies with larger sample size and longer follow-up are warranted to confirm these findings and to identify the optimal plasma folate level for cognitive function.

Aging of the Immune System: Focus on Natural Killer Cells Phenotype and Functions

Aging is the greatest risk factor for nearly all major chronic diseases, including cardiovascular diseases, cancer, Alzheimer’s and other neurodegenerative diseases of aging. Age-related impairment of immune function (immunosenescence) is one important cause of age-related morbidity and mortality, which may extend beyond its role in infectious disease. One aspect of immunosenescence that has received less attention is age-related natural killer (NK) cell dysfunction, characterized by reduced cytokine secretion and decreased target cell cytotoxicity, accompanied by and despite an increase in NK cell numbers with age. Moreover, recent studies have revealed that NK cells are the central actors in the immunosurveillance of senescent cells, whose age-related accumulation is itself a probable contributor to the chronic sterile low-grade inflammation developed with aging (“inflammaging”). NK cell dysfunction is therefore implicated in the increasing burden of infection, malignancy, inflammatory disorders, and senescent cells with age. This review will focus on recent advances and open questions in understanding the interplay between systemic inflammation, senescence burden, and NK cell dysfunction in the context of aging. Understanding the factors driving and enforcing NK cell aging may potentially lead to therapies countering age-related diseases and underlying drivers of the biological aging process itself.

High serum folate level is positively associated with pulmonary function in elderly Korean men, but not in women

A limited number of studies have been conducted on the relationship between serum vitamin levels and pulmonary function, particularly in the elderly population. This study attempted to confirm the association between serum vitamin levels (folate, vitamin A, and vitamin E) and pulmonary function in the elderly population of Korea. A total of 1166 subjects (528 men and 637 women) participated in the Korean National Health and Nutrition Examination Survey from 2016 to 2018. Serum levels of folate, vitamin A, and vitamin E were measured in the subjects. The subjects’ pulmonary function measurement items were as follows: forced vital capacity (FVC), forced expiratory volume in one second (FEV1), forced expiratory volume in one second/forced vital capacity (FEV1/FVC), forced expiratory flow at 25% and 75% of the pulmonary volume (FEF25–75%), forced expiratory volume in 6 s (FEV6), and peak expiratory velocity (PEV). We performed regression analysis considering FEV1, PEV, FVC, FEF25–75%, and FEV1/FVC and FEV6 as dependent variables. Serum vitamin A levels were not associated with pulmonary function. In elderly men, serum vitamin E levels were negatively correlated with FVC [B =  − 0.012, 95% confidence interval (CI) − 0.022 to − 0.003, p = 0.012] and FEV1 (B =  − 0.010, 95% CI − 0.115 to − 0.007, p = 0.028). We confirmed a positive correlation of the serum folate level with FEV1 (B = 0.017, 95% CI 0.004–0.030, p = 0.009), FEV1/FVC (B = 0.003, 95% CI 0.001–0.005, p = 0.007), and FEF25–75% (B = 0.031, 95% CI 0.010–0.053, p = 0.005) in elderly men. This study confirmed that high serum folate levels were positively associated with pulmonary function in elderly men in Korea. Further studies are needed to understand the longitudinal effect of folate and its biological mechanism in pulmonary function.

Examining the impact of socioeconomic status, demographic characteristics, lifestyle and other risk factors on adults' cognitive functioning in developing countries: an analysis of five selected WHO SAGE Wave 1 Countries

BACKGROUND

Though extensive studies have been conducted on assessing the predictors of cognitive functioning among older adults in small community-based samples, very few studies have focused on understanding the impact of socioeconomic status (SES), demographic characteristics and other risk factors such as lifestyle and chronic diseases on the cognitive functioning among adults of all ages in a nationally representative population-based sample across low- and middle-income countries. This study, therefore, seeks to evaluate the impact of SES, demographic characteristics and risk factors on the cognitive functioning of adults across all ages in five selected developing countries.

METHODS

Data from 12,430 observations obtained from the WHO Study on Global AGEing and Adult Health (SAGE) Wave 1; consisting of 2,486 observations each for China, Ghana, India, the Russian Federation, and South Africa, were used for the study. A meta-regression and a five-step hierarchical linear regression were used to analyze the data, with cognitive functioning as the dependent variable. Independent variables used in this study include SES; assessed by household income and education, demographic characteristics, other risk factors such as lifestyle, self-reported memory difficulty and chronic diseases.

RESULTS

This study found that SES and lifestyle significantly predicted cognitive functioning in all the five selected countries as obtained by the pooled results of the meta-regression analysis. The hierarchical linear regression results also revealed that demographic characteristics such as age, type of residency, and self-reported memory difficulty significantly impact cognitive functioning in China, Ghana, Russia, and South Africa.

CONCLUSION

The findings in this study provide new insights for policymakers, caregivers, parents, and individuals, especially those in developing countries, to implement policies and actions targeted at improving SES and eliminating risk factors associated with cognitive decline, as these measures could help improve the cognitive functioning among their populations.

Mechanistic Link between Vitamin B12 and Alzheimer's Disease

Alzheimer's disease (AD) is the most common form of dementia in the elderly population, affecting over 55 million people worldwide. Histopathological hallmarks of this multifactorial disease are an increased plaque burden and tangles in the brains of affected individuals. Several lines of evidence indicate that B12 hypovitaminosis is linked to AD. In this review, the biochemical pathways involved in AD that are affected by vitamin B12, focusing on APP processing, Aβ fibrillization, Aβ-induced oxidative damage as well as tau hyperphosphorylation and tau aggregation, are summarized. Besides the mechanistic link, an overview of clinical studies utilizing vitamin B supplementation are given, and a potential link between diseases and medication resulting in a reduced vitamin B12 level and AD are discussed. Besides the disease-mediated B12 hypovitaminosis, the reduction in vitamin B12 levels caused by an increasing change in dietary preferences has been gaining in relevance. In particular, vegetarian and vegan diets are associated with vitamin B12 deficiency, and therefore might have potential implications for AD. In conclusion, our review emphasizes the important role of vitamin B12 in AD, which is particularly important, as even in industrialized countries a large proportion of the population might not be sufficiently supplied with vitamin B12.

Relation Between Methylenetetrahydrofolate Reductase Polymorphisms (C677T and A1298C) and Migraine Susceptibility

Migraine is a neurological disorder which impairs the patient's quality of life. Several association studies investigating the association between MTHFR gene C677T and A1298C polymorphisms and susceptibility to migraine were published. But the results were conflicting, so authors performed a meta-analysis of published case control studies to find out the exact association between MTHFR polymorphism and migraine susceptibility. Four databases were searched for suitable studies up to December, 2018. Odds ratios (OR) with 95% confidence intervals (CI) was calculated adopting additive, homozygote, co-dominant, dominant, and recessive genetic models. Results of MTHFR C677T polymorphism studies meta-analysis showed significant association with migraine risk using allele contrast, homozygote, dominant and recessive genetic models (T vs. C: OR = 1.18, 95% CI = 1.00-1.26, p = 0.05; TT vs. CC: OR = 1.24, 95% CI = 1.0-1.5, p = 0.04; CT vs. CC: OR = 1.08, 95% CI = 0.97-1.07, p = 0.25; TT + CT vs. CC: OR = 1.15, 95% CI = 1.0-1.29, p = 0.04; TT vs. CT + CC: OR = 1.97, 95% CI = 1.28-3.42, p = 0.002). However, results of MTHFR A1298 polymorphism studies meta-analysis did not show any association with migraine. Subgroup analysis based on ethnicity and migraine types i.e. migraine with aura (MA) and without aura (MO) were also performed. Results of present meta-analysis indicate overall association between MTHFR C677T polymorphism with migraine in total 24 studies, in Asian population and in MA cases but did not show any association with Caucasian population and MO cases.

Diagnostic Values of Serum Levels of Homocysteine, Heat Shock Protein 70 and High-Sensitivity C-Reactive Protein for Predicting Vascular Cognitive Impairment

INTRODUCTION

Vascular cognitive impairment is one of the main clinical manifestations of cerebral small vessel disease (CSVD). Reliable molecular markers are needed urgently to predict cognitive impairments in CSVD patients. This study aimed to investigate the possible diagnostic values of serum levels of Hcy, Hsp70 and hs-CRP for predicting vascular cognitive impairment in patients with CSVD.

METHODS

According to the presence of CSVD and cognitive impairment (CI), healthy patients and CSVD patients were divided into three groups. Serum Hcy, HSP70 and hs-CRP were abnormal in the CI group. Clinical characteristics and MOCA cognitive function score statistics were performed for the three groups: the control group, CSVD without cognitive impairment group and CSVD with cognitive impairment group. Finally, Hcy, HSP70 and hs-CRP were correlated with MOCA to analyze the correlation between serum Hcy, HSP70 and hs-CRP and cognitive dysfunction caused by CSVD.

RESULTS

The levels of serum Hcy, Hsp70, and hsCRP had significantly higher expression in the CSVD groups than those in the control group (p<0.05). Moreover, basic clinical characteristics, cardiovascular risk factors and other clinical details had no significantly differences among the three groups. Serum Hcy, Hsp70 and hs-CRP levels were negatively correlated with MoCA total scores.

CONCLUSION

Serum levels of Hcy, HSP70 and hs-CRP were negatively correlated with cognitive impairment caused by CSVD, which could be used as a predictor to predict the risk of cognitive impairment caused by CSVD.

Dietary supplements, vitamins and minerals as potential interventions against viruses: Perspectives for COVID-19

The novel coronavirus (SARS-CoV-2) causing COVID-19 disease pandemic has infected millions of people and caused more than thousands of deaths in many countries across the world. The number of infected cases is increasing day by day. Unfortunately, we do not have a vaccine and specific treatment for it. Along with the protective measures, respiratory and/or circulatory supports and some antiviral and retroviral drugs have been used against SARS-CoV-2, but there are no more extensive studies proving their efficacy. In this study, the latest publications in the field have been reviewed, focusing on the modulatory effects on the immunity of some natural antiviral dietary supplements, vitamins and minerals. Findings suggest that several dietary supplements, including black seeds, garlic, ginger, cranberry, orange, omega-3 and -6 polyunsaturated fatty acids, vitamins (e.g., A, B vitamins, C, D, E), and minerals (e.g., Cu, Fe, Mg, Mn, Na, Se, Zn) have anti-viral effects. Many of them act against various species of respiratory viruses, including severe acute respiratory syndrome-related coronaviruses. Therefore, dietary supplements, including vitamins and minerals, probiotics as well as individual nutritional behaviour can be used as adjuvant therapy together with antiviral medicines in the management of COVID-19 disease.

Isotretinoin and neuropsychiatric side effects: Continued vigilance is needed

Background

Isotretinoin (13-cis-retinoic acid, marketed under the names Accutane, Roaccutane, and others) is an effective treatment for acne that has been on the market for over 30 years, although reports of neuropsychiatric side effects continue to be reported. Isotretinoin is an isomer of the active form of Vitamin A, 13-trans-retinoic acid, which has known psychiatric side effects when given in excessive doses, and is part of the family of compounds called retinoids, which have multiple functions in the central nervous system.

Methods

The literature was reviewed in pubmed and psychinfo for research related to isotretinoin and neuropsychiatric side effects including depression, suicidal thoughts, suicide, mania, anxiety, impulsivity, emotional lability, violence, aggression, and psychosis.

Results

Multiple case series have shown that successful treatment of acne with isotretinoin results in improvements in measures of quality of life and self esteem However, studies show individual cases of clinically significant depression and other neuropsychiatric events that, although not common, are persistent in the literature. Since the original cases of depression were reported to the United States Food and Drug Administration, numerous cases have been reported to regulatory agencies in the United Kingdom, France, Ireland, Denmark, Australia, Canada, and other countries, making isotretinoin one of the top five medications in the world associated with depression and other neuropsychiatric side effects. Clinicians are advised to warn patients of the risks of neuropsychiatric side effects with isotretinoin which may arise from the medication itself, and not just as a side effect of acne or youth.

A Revisit to Etiopathogenesis and Therapeutic Strategies in Alzheimer's Disease

Dementia is a cluster of brain abnormalities that trigger progressive memory deficits and other cognitive abilities such as skills, language, or executive function. Alzheimer's disease (AD) is the foremost type of age-associated dementia that involves progressive neurodegeneration accompanied by profound cognitive deficits in advanced stages that severely hamper social or occupational abilities with or without the involvement of any other psychiatric condition. The last two decades witnessed a sharp increase (~123%) in mortality due to AD type dementia, typically owing to a very low disclosure rate (~45%) and hence, the prophylactic, as well as the therapeutic cure of AD, has been a huge challenge. Although understanding of AD pathogenesis has witnessed a remarkable growth (e.g., tauopathy, oxidative stress, lipid transport, glucose uptake, apoptosis, synaptic dysfunction, inflammation, and immune system), still a dearth of an effective therapeutic agent in the management of AD prompts the quest for newer pharmacological targets in the purview of its growing epidemiological status. Most of the current therapeutic strategies focus on modulation of a single target, e.g., inhibition of acetylcholinesterase, glutamate excitotoxicity (memantine), or nootropics (piracetam), even though AD is a multifaceted neurological disorder. There is an impedance urgency to find not only symptomatic but effective disease-modifying therapies. The present review focuses on the risk / protective factors and pathogenic mechanisms involved in AD. In addition to the existing symptomatic therapeutic approach, a diverse array of possible targets linked to pathogenic cascades have been re-investigated to envisage the pharmacotherapeutic strategies in AD.

Pyriproxyfen exposure induces DNA damage, cell proliferation impairments and apoptosis in the brain vesicles layers of chicken embryos

Larvicide pyriproxyfen (PPF), used in drinking water reservoirs to control Aedes mosquitoes, has already been shown as a possible cause of congenital anomalies in the central nervous system. However, the neurotoxic effects of PPF on the development of vertebrate embryos are still underexplored. Thus, the aim of this study was to investigate the effects of PPF on the morphometric parameters of the head and brain, as well as on the cell layers of the forebrain and midbrain, using embryos of Gallus domesticus as a model. Two sublethal PPF concentrations (0.01 mg/L and 10 mg/L), as defined by a survival curve, were tested. Analysis of the biometry of embryos showed significant reduction in body and brain mass and also in measurements of the head and brain. A reduction in cell layer thickness of the forebrain and midbrain was observed, accompanied by a reduction in the numerical density of cells per area. Changes in brain and head sizes and in the thickness of the cell layers of the forebrain and midbrain were significant at 10 mg/L PPF. Notably, PPF caused DNA doublestrand breaks and induced apoptosis in embryos exposed to 10 mg/L, which were accompanied by a reduction in cell proliferation. Regarding neuronal and glial differentiation, no changes were observed in the number of neurons and glial cells on the analyzed layers. Furthermore, PPF did not impact the head ossification process. These findings reveal that PPF is a strong stressor for neurodevelopment, causing damage to the cell architecture of brain vesicles.

Hyperhomocysteinemia: Metabolic Role and Animal Studies with a Focus on Cognitive Performance and Decline-A Review

Disturbances in the one-carbon metabolism are often indicated by altered levels of the endogenous amino acid homocysteine (HCys), which is additionally discussed to causally contribute to diverse pathologies. In the first part of the present review, we profoundly and critically discuss the metabolic role and pathomechanisms of HCys, as well as its potential impact on different human disorders. The use of adequate animal models can aid in unravelling the complex pathological processes underlying the role of hyperhomocysteinemia (HHCys). Therefore, in the second part, we systematically searched PubMed/Medline for animal studies regarding HHCys and focused on the potential impact on cognitive performance and decline. The majority of reviewed studies reported a significant effect of HHCys on the investigated behavioral outcomes. Despite of persistent controversial discussions about equivocal findings, especially in clinical studies, the present evaluation of preclinical evidence indicates a causal link between HHCys and cognition-related- especially dementia-like disorders, and points out the further urge for large-scale, well-designed clinical studies in order to elucidate the normalization of HCys levels as a potential preventative or therapeutic approach in human pathologies.

A Multivariate Assessment of Age-Related Cognitive Impairment in Octodon degus

Aging is a progressive functional decline characterized by a gradual deterioration in physiological function and behavior. The most important age-related change in cognitive function is decline in cognitive performance (i.e., the processing or transformation of information to make decisions that includes speed of processing, working memory, and learning). The purpose of this study is to outline the changes in age-related cognitive performance (i.e., short-term recognition memory and long-term learning and memory) in long-lived Octodon degus. The strong similarity between degus and humans in social, metabolic, biochemical, and cognitive aspects makes it a unique animal model for exploring the mechanisms underlying the behavioral and cognitive deficits related to natural aging. In this study, we examined young adult female degus (12- and 24-months-old) and aged female degus (38-, 56-, and 75-months-old) that were exposed to a battery of cognitive-behavioral tests. Multivariate analyses of data from the Social Interaction test or Novel Object/Local Recognition (to measure short-term recognition memory), and the Barnes maze test (to measure long-term learning and memory) revealed a consistent pattern. Young animals formed a separate group of aged degus for both short- and long-term memories. The association between the first component of the principal component analysis (PCA) from short-term memory with the first component of the PCA from long-term memory showed a significant negative correlation. This suggests age-dependent differences in both memories, with the aged degus having higher values of long-term memory ability but poor short-term recognition memory, whereas in the young degus an opposite pattern was found. Approximately 5% of the young and 80% of the aged degus showed an impaired short-term recognition memory; whereas for long-term memory about 32% of the young degus and 57% of the aged degus showed decreased performance on the Barnes maze test. Throughout this study, we outlined age-dependent cognitive performance decline during natural aging in degus. Moreover, we also demonstrated that the use of a multivariate approach let us explore and visualize complex behavioral variables, and identified specific behavioral patterns that allowed us to make powerful conclusions that will facilitate further the study on the biology of aging. In addition, this study could help predict the onset of the aging process based on behavioral performance.

Analysis of the Impact of Selected Vitamins Deficiencies on the Risk of Disability in Older People

Vitamin deficiencies have a serious impact on healthy aging in older people. Many age-related disorders have a direct or indirect impact on nutrition, both in terms of nutrient assimilation and food access, which may result in vitamin deficiencies and may lead to or worsen disabilities. Frailty is characterized by reduced functional abilities, with a key role of malnutrition in its pathogenesis. Aging is associated with various changes in body composition that lead to sarcopenia. Frailty, aging, and sarcopenia all favor malnutrition, and poor nutritional status is a major cause of geriatric morbidity and mortality. In the present narrative review, we focused on vitamins with a significant risk of deficiency in high-income countries: D, C, and B (B6/B9/B12). We also focused on vitamin E as the main lipophilic antioxidant, synergistic to vitamin C. We first discuss the role and needs of these vitamins, the prevalence of deficiencies, and their causes and consequences. We then look at how these vitamins are involved in the biological pathways associated with sarcopenia and frailty. Lastly, we discuss the critical early diagnosis and management of these deficiencies and summarize potential ways of screening malnutrition. A focused nutritional approach might improve the diagnosis of nutritional deficiencies and the initiation of appropriate clinical interventions for reducing the risk of frailty. Further comprehensive research programs on nutritional interventions are needed, with a view to lowering deficiencies in older people and thus decreasing the risk of frailty and sarcopenia.

Plasma homocysteine concentrations and depression: A twin study

Background

Homocysteine is an amino acid formed during metabolism of the essential amino acid methionine that plays an important role in energy metabolism and neurotransmitter synthesis. High levels of homocysteine have been linked to both depression and cardiovascular disease, however studies of depression have not always been consistent, possibly related to differences in methodology among studies. The study of twins in clinical research can be useful in controlling for confounding factors. The purpose of this study was to assess the relationship between depression and plasma homocysteine in a study of twins.

Methods

Homocysteine concentration was assessed in twins (N = 202) from the Vietnam Era Twin Registry, including twin pairs discordant for the diagnosis of Major Depressive Disorder (MDD) and twin pairs without MDD. Self reported depressive symptom levels were also measured as a continous variable using the Beck Depression Inventory (BDI).

Results

The average homocysteine concentration was 7.9 μmol/L (2.1 μmol/L SD, range of 2.0-17.1 μmol/L). There were no within twin pair differences in homocysteine concentration within twin pairs discordant for MDD and within twin pairs that differed for BDI score. There was a significant pair-level relationship between depressive symptoms as measured by mean BDI score and homocysteine concentration, such that the higher the mean BDI score of the twin pair, the higher the mean homocystein of the pair (p < .001). Every 10 point increase in BDI score was associated with an 0.8 μmol/L increase in homocysteine concentration at the pair level.

Conclusions

These findings are not consistent with a causal role for elevated homocysteine in the development of depression, but rather point to familial confounding or other factors that are shared by twin brothers and that contribute to both depression and homocysteine levels.

Association Between Homocysteine and Vitamin Levels in Demented Patients

BACKGROUND

Although it is known that the nutritional status among elderly persons and, in particular, patients with dementia, is compromised, malnutrition that results in insufficient uptake of several vitamins is often not diagnosed.

OBJECTIVE

An elevated homocysteine level is a known strong risk factor for vascular dementia (VaD) and Alzheimer's disease (AD). Several B vitamins are involved in the metabolism of homocysteine. Therefore, we investigated the serum levels of vitamin B1, vitamin B6, folate, and vitamin B12 in 97 patients with mild cognitive impairment (MCI) or different forms of dementia and 54 elderly control persons without dementia.

RESULTS

Compared to aged non-demented people, vitamins B1, B6, B12, and folate were decreased in serum of patients with AD, and patients with Lewy body dementia had reduced vitamin B12 level. Vitamin B6 was diminished in VaD. Patients with frontotemporal dementia showed no alterations in vitamin levels. Age was identified as an important factor contributing to the concentrations of vitamin B1 and B6 in serum, but not vitamin B12 and folate. Increased levels of total homocysteine were detected especially in MCI and AD. Homocysteine correlated negatively with levels of vitamins B6, B12, and folate and positively with Q Albumin.

CONCLUSION

Our data suggest that despite increased homocysteine already present in MCI, vitamin levels are decreased only in dementia. We propose to determine the vitamin levels in patients with cognitive decline, but also elderly people in general, and recommend supplementing these nutrients if needed.