Analysis of Forsythia suspensa fruit and leaf extracts using UHPLC-Q-Exactive-Orbitrap/MS: In vivo antioxidant activity on D-galactose-induced aging mice.

Making health-enhancing tea from Forsythia suspensa leaves has been a tradition of Chinese folk culture for centuries. However, these leaves were not officially recognized as a new food source until 2017 by the Chinese government. In this study, ethyl acetate fractions from Forsythia suspensa fruit and leaves exhibited excellent antioxidant activity in vitro antioxidant assays and in vivo D-galactose-induced aging mice model. The antioxidant activity of the leaves was higher than that of fruit both in vitro and in vivo. The chemical constituents present in these ethyl acetate fractions were comprehensively analyzed using UHPLC-Q-Exactive-Orbitrap/MS. A total of 20 compounds were identified, among which forsythoside E, (+)-epipinoresinol, dihydromyricetin, chlorogenic acid, and ursolic acid were exclusively detected in the ethyl acetate fraction of Forsythia suspensa leaves, but absent in the ethyl acetate fraction derived from its fruit. This study provides theoretical support for the utilization of Forsythia suspensa fruit and leaves.

γδ T-Cell Immunophenotype for the Study of Human Aging.

Flow cytometry serves as a crucial tool in immunology, allowing for the detailed analysis of immune cell populations. γδ T cells, a subset of T cells, play pivotal roles in immune surveillance and immune aging. Assessing the phenotype and functional capabilities of γδ T cells isolated from whole blood or tissue within the context of human aging yields invaluable insights into the dynamic changes affecting immune function, tissue homeostasis, susceptibility to infections, and inflammatory responses.

Application of Multiplex Immunoassay in Aging Research: A Methodological Approach.

One of the characteristics of aging and age-related disorders is the formation and evolution of a chronic, low-grade, and hence subclinical, inflammatory state known as inflammaging. Although the progression of inflammaging is now recognized as one of the main driving forces of aging and one of the main risk factors for morbidity and mortality in older subjects, current knowledge on the causative agents of inflammaging itself and chronic, aging-related diseases is still incomplete. In this chapter, we offer a methodological approach for assessing inflammation associated with aging through the use of multiplex immunoassay, which enables the rapid, reproducible, and simultaneous dosage of several cytokines, chemokines, and inflammatory mediators with little biological sample usage.

Analysis of Cytokine-Inducible SH2-Containing Protein (CISH) in the Study of Immunosenescence.

The aging immune system undergoes significant changes, leading to a state known as immunosenescence. Understanding the molecular mechanisms underlying immunosenescence is crucial for developing targeted interventions to enhance immune functions in older individuals. This bio-protocol review focuses on the application of quantitative reverse transcription-polymerase chain reaction (qRT-PCR) for the mRNA quantification of cytokine-inducible SH2-containing protein (CISH), an immune regulator overexpressed in T-cell responses from older adults. We outline a comprehensive protocol for the quantitative assessment of CISH mRNA expression, providing a valuable tool for researchers investigating immunosenescence.

Characterization of Age-Dependent Changes in Skeletal Muscle Repair and Regeneration Using a Mouse Model of Acute Muscle Injury.

Acute skeletal muscle injury initiates a process of necrosis, debris clearance, and ultimately tissue regeneration via myogenesis. While skeletal muscle stem cells (MuSCs) are responsible for populating the proliferative myogenic progenitor pool to fuel muscle repair, recruited and resident immune cells have a central role in the regulation of muscle regeneration via the execution of phagocytosis and release of soluble factors that act directly on MuSCs to regulate myogenic differentiation. Therefore, the timing of MuSC proliferation and differentiation is closely linked to the populations and behaviors of immune cells present within skeletal muscle. This has important implications for aging and muscle repair, as systemic changes in immune system function contribute to a decline in muscle regenerative capacity. Here, we present adapted protocols for the isolation of mononuclear cells from skeletal muscles for the quantification of immune cell populations using flow cytometry. We also describe a cardiotoxin skeletal muscle injury protocol and detail the expected outcomes including immune cell infiltration to the injured sites and formation of new myocytes. As immune cell function is substantially influenced by aging, we extend these approaches and outcomes to aged mice.

Recording of Age-Related Changes on Murine and Human Brain Slices.

Preparation of brain slices for electrophysiological and imaging experiments has been developed several decades ago, and the method is still widely used due to its simplicity and advantages over other techniques. It can be easily combined with other well established and recently developed methods as immunohistochemistry and morphological analysis or opto- and chemogenetics. Several aspects of this technique are covered by a plethora of excellent and detailed review papers, in which one can gain a deep insight of variations in it. In this chapter, I briefly describe the solutions, equipment, and preparation techniques routinely used in our laboratory. I also aim to present how certain "old school" brain slice lab devices can be made in a cost-efficient way. These devices can be easily adapted for the special needs of the experiments. I also aim to present some differences in the preparatory techniques of acutely isolated human brain tissue.

The Comparative Effects Between Long-Term and Short-Term Treatment of Finasteride on Anxiety-Like and Depression-Like Behaviors in Early Senescent Male Rats.

This study aims to compare the efficacy of 5-alpha-reductase inhibitors (5ARIs) on anxiety and depression between long-term and short-term treatment followed by withdrawal in d-galactose (Dgal)-induced senescent male rats. Thirty-two, 8-week-old, male Wistar rats were divided into two groups: control rats and Dgal-treated rats (150 mg/kg/day; subcutaneously) for 18 weeks. At week 13, Dgal-treated rats were subdivided into three subgroups: (1) vehicle (DgV), (2) long-term treatment with 5ARIs, Finasteride 5 mg/kg/day, per oral for 6 weeks (DgF), (3) short-term treatment with 5ARIs, Finasteride 5 mg/kg/day, per oral for 2 weeks followed by a 4-week withdrawal period (DgW). Anxiety and depression were assessed using the elevated-plus maze (EPM) and splash test (ST). Blood was collected for biochemical analysis. After euthanasia, the brains were removed to examine brain inflammation, oxidative stress, neuroactive steroids, brain metabolites, and brain senescent markers. We found that DgV rats exhibited metabolic disturbance with a reduced preference index of the EPM, and grooming duration in ST. Increased brain neurotoxic metabolites, along with increased brain inflammation/oxidative stress, and reduced microglia complexity were observed in the DgV rats. Both therapeutic approaches improved metabolic parameters and preference index in the open arm of EPM in Dgal-treated rats, while grooming duration and microglia complexity were increased only in DgF rats. Our results indicate that Fin reduces depression-like and anxiety-like behaviors by reducing brain inflammation, oxidative stress, and brain senescent. In conclusion, long-term treatment with 5ARIs is more effective in alleviating depression than short-term treatment followed by withdrawal in Dgal-induced early senescent male rats.

[Knockout of Hsp70 Genes Modulates Age-Related Transcriptomic Changes in Leg Muscles and Reduces the Locomotion Speed and Lifespan of Drosophila melanogaster].

This study investigated the effect of knockout of six Hsp70 genes (orthologues of the mammalian genes Hspa1a, Hspa1b, Hspa2, and Hspa8) on age-related changes in gene expression in the legs of Drosophila melanogaster, which contain predominantly skeletal muscle bundles. For this, the leg transcriptomic profile was examined in males of the w^(1118) control strain and the Hsp70^(-) strain on the 7th, 23rd and 47th days of life. In w^(1118) flies, an age-related decrease in the locomotion (climbing) speed (a marker of functional state and endurance) was accompanied by a pronounced change in the transcriptomic profile of the leg skeletal muscles, which is conservative in nature. In Hsp70^(-) flies, the median lifespan was shorter and the locomotion speed was significantly lower compared to the control; at the same time, complex changes in the age-related dynamics of the skeletal muscle transcriptome were observed. Mass spectrometry-based quantitative proteomics showed that 47-day-old Hsp70^(-) flies, compared with w^(1118) flies, demonstrated multidirectional changes in the contents of key enzymes of glucose metabolism and fat oxidation (glycolysis, pentose phosphate pathway, Krebs cycle, beta-oxidation, and oxidative phosphorylation). Such dysregulation may be associated with a compensatory increase in the expression of other genes encoding chaperones (small Hsp, Hsp40, 60, and 70), which regulate specific sets of target proteins. Taken together, our data show that knockout of six Hsp70 genes slightly reduced the median lifespan of flies, but significantly reduced the locomotion speed, which may be associated with complex changes in the transcriptome of the leg skeletal muscles and with multidirectional changes in the contents of key enzymes of energy metabolism.

A germline-to-soma signal triggers an age-related decline of mitochondrial stress response.

The abilities of an organism to cope with extrinsic stresses and activate cellular stress responses decline during aging. The signals that modulate stress responses in aged animals remain to be elucidated. Here, we discover that feeding Caenorhabditis elegans (C. elegans) embryo lysates to adult worms enabled the animals to activate the mitochondrial unfolded protein response (UPRmt) upon mitochondrial perturbations. This discovery led to subsequent investigations that unveil a hedgehog-like signal that is transmitted from the germline to the soma in adults to inhibit UPRmt in somatic tissues. Additionally, we find that the levels of germline-expressed piRNAs in adult animals markedly decreased. This reduction in piRNA levels coincides with the production and secretion of a hedgehog-like signal and suppression of the UPRmt in somatic cells. Building upon existing research, our study further elucidates the intricate mechanisms of germline-to-soma signaling and its role in modulating the trade-offs between reproduction and somatic maintenance within the context of organismal aging.

Demographic, socioconomic, and health correlates of sleep quality and sleep duration among community-dwelling older adults in India.

BACKGROUND: Recent research has revealed that today's older adults report more sleep problems than their predecessors, a trend compounded by expanding social stratification. As such, this study examined the demographic, socioeconomic, and health correlates of sleep quality and sleep duration among community-dwelling older adults in India. METHODS: The current study sample draws on data from 7118 respondents aged 50 years and over participating in the World Health Organization's Study on global AGEing and adult health (WHO-SAGE) wave-2 dataset. Sleep quality (good, moderate, and poor) and sleep duration (in hours and minutes) were self-reported. Adjusted multivariable logistic regression models were employed to examine the associations between sleep quality and sleep duration and several demographic, socioeconomic, and health indicators. RESULTS: A total of 12.84% and 36.1% of older adults reported long (> 8 h) and short (< 7 h) sleep, respectively. Older adults with primary education had lower odds of poor sleep [aOR: 0.85, CI: 0.73-0.99] than peers with no formal education. The odds of poor sleep were lower among those in higher wealth quintiles than those in the poorest quintile. Older adults with higher education had higher odds of short sleep [aOR: 1.36, CI: 1.06-1.74], and those with primary education had lower odds of long sleep [aOR: 0.70, CI: 0.54-0.91] than those without formal education (base category: age-appropriate sleep, i.e., 7-8 h). Older adults who were widowed had lower odds of both short [aOR: 0.82, CI: 0.68-0.98] and long sleep [aOR:0.74, CI: 0.58-0.95] compared to those who were currently married. Older individuals with adequate nutritional intake reported lower odds of short [aOR:0.59, CI: 0.49-0.72] and higher odds of long sleep [aOR:1.52, CI: 1.20-1.93] relative to their counterparts. Older adults who reported chronic conditions and body pain had higher odds of poor sleep and short sleep than their counterparts. CONCLUSIONS: We identified significant associations between several unmodifiable factors, including age, education, and marital status, and modifiable factors such as dietary intake, body pain, and pre-existing chronic ailments, and sleep quality and sleep duration. Our findings can assist health care providers and practitioners in developing a more holistic and empathic approach to care. Moreover, that several demographic, socioeconomic, and health-related factors are consequential for older adults' sleep health suggests that early detection through screening programs and community-based interventions is vital to improving sleep among older Indians who are most susceptible to sleep problems.

The fetal origins of metabolic health: exploring the association between newborn biological age and metabolism hormones in childhood.

BACKGROUND: Telomere length (TL), mitochondrial DNA copy number (mtDNAcn), and DNA methylation age (DNAmAge) are common aging biomarkers. However, research on the associations between these three markers at birth and subsequent metabolic status was limited. This study aimed to evaluate the association between TL, mtDNAcn, and DNAmAge in newborns and the variation in metabolic hormones of children at 3 years old. METHODS: This research involved 895 mother-child pairs from a birth cohort in China, with TL and mtDNAcn measured using quantitative real-time PCR, DNA methylation (DNAm) assessed using Infinium MethylationEPIC Beadchip, and DNAm age (DNAmAge) determined using Horvath's epigenetic clock. Insulin and leptin levels were measured via electrochemiluminescence assay. Multivariable adjusted linear regression and restricted cubic spline (RCS) analysis were utilized to examine the association between aging markers and metabolic hormones. RESULTS: The linear regression analysis indicated the percentage change of metabolism hormones for per doubling of aging biomarkers alterations and found significant associations between DNAmAge and insulin levels (adjusted percent change (95% CI), - 13.22 (- 23.21 to - 1.94)), TL and leptin levels (adjusted percent change (95% CI), 15.32 (1.32 to 31.24)), and mtDNAcn and leptin levels (adjusted percent change (95% CI), - 14.13 (- 21.59 to - 5.95)). The RCS analysis revealed significant non-linear associations between TL (Ln transformed) and insulin (Ln transformed) (P = 0.024 for nonlinearity), as well as DNAmAge (Ln transformed) and leptin (Ln transformed) (P = 0.043 for nonlinearity). Specifically, for TL and insulin, a positive association was observed when TL (Ln transformed) was less than - 0.05, which transitioned to an inverse association when TL (Ln transformed) was greater than - 0.05. Regarding DNAmAge and leptin, there was a sharp decline when DNAmAge (Ln transformed) was less than - 1.35, followed by a plateau between - 1.35 and - 0.67 and then a further decline when DNAmAge (Ln transformed) was greater than - 0.67. CONCLUSIONS: In this prospective birth cohort study, variation in metabolic hormones of children at 3 years old was associated with TL, mtDNAcn, and DNAmAge at birth. These findings suggested that TL, mtDNAcn, and DNAmAge might play a role in the biological programming of metabolic health from birth.

The Influence of Structural Brain Changes on Cognition in the Context of Healthy Aging: Exploring Mediation Effects Through gBAT-The Graphical Brain Association Tool.

The contribution of age-related structural brain changes to the well-established link between aging and cognitive decline is not fully defined. While both age-related regional brain atrophy and cognitive decline have been extensively studied, the specific mediating role of age-related regional brain atrophy on cognitive functions is unclear. This study introduces an open-source software tool with a graphical user interface that streamlines advanced whole-brain mediation analyses, enabling researchers to systematically explore how the brain acts as a mediator in relationships between various behavioral and health outcomes. The tool is showcased by investigating regional brain volume as a mediator to determine the contribution of age-related brain volume loss toward cognition in healthy aging. We analyzed regional brain volumes and cognitive testing data (Montreal Cognitive Assessment [MoCA]) from a cohort of 131 neurologically healthy adult participants (mean age 50 ± 20.8 years, range 20-79, 73% females) drawn from the Aging Brain Cohort Study at the University of South Carolina. Using our open-source tool developed for evaluating brain-behavior associations across the brain and optimized for exploring mediation effects, we conducted a series of mediation analyses using participant age as the predictor variable, total MoCA and MoCA subtest scores as the outcome variables, and regional brain volume as potential mediators. Age-related atrophy within specific anatomical networks was found to mediate the relationship between age and cognition across multiple cognitive domains. Specifically, atrophy in bilateral frontal, parietal, and occipital areas, along with widespread subcortical regions mediated the effect of age on total MoCA scores. Various MoCA subscores were influenced by age through atrophy in distinct brain regions. These involved prefrontal regions, sensorimotor cortex, and parieto-occipital areas for executive function subscores, prefrontal and temporo-occipital regions, along with the caudate nucleus for attention and concentration subscores, frontal and parieto-occipital areas, alongside connecting subcortical areas such as the optic tract for visuospatial subscores and frontoparietal areas for language subscores. Brain-based mediation analysis offers a causal framework for evaluating the mediating role of brain structure on the relationship between age and cognition and provides a more nuanced understanding of cognitive aging than previously possible. By validating the applicability and effectiveness of this approach and making it openly available to the scientific community, we facilitate the exploration of causal mechanisms between variables mediated by the brain.

Regional variation in prevalence of frailty in India: Evidence from longitudinal ageing study in India (LASI) wave-1.

Background & objectives Frailty is a geriatric syndrome with clinical and public health implications. It represents the state of increased vulnerability. This study aimed to estimate the prevalence of frailty and pre-frailty by demographic characteristics and geographical regions in India. Furthermore, it also aimed to examine the association of this prevalence with selected health outcomes using data from the Longitudinal Ageing Study of India (LASI). Methods This is a secondary analysis of LASI wave-1 data. A total of 26,058 respondents aged ≥60 yr were included for analysis. Frailty was assessed using Fried's frailty phenotype, including slowness, shrinking, low physical activity, weakness, and low endurance. Descriptive statistics were used to study frailty distribution. The odds ratio (OR) of health events across the frailty categories was computed using ordinal logistic regression. Results The findings of this study suggest that the prevalence of frailty and pre-frailty was 29.2 and 58.8 per cent, respectively. The prevalence of frailty was higher among women (37.3%), illiterate (37%) and rural residents (31%). It ranged between 14.5 per cent in Uttarakhand and 41.3 per cent in Arunachal Pradesh. Frailty was strongly associated with depression [OR: 2.09, Confidence Interval (CI): 1.98-2.21] and activities of daily living (ADL) difficulty (OR: 1.75, CI: 1.64-1.86). Higher odds were reported for fracture (OR: 1.24, CI: 1.01-1.51) and multimorbidity (OR: 1.18, CI: 1.04-1.33) among frailty. Interpretation & conclusions The heterogeneity of frailty prevalence across States indicates the need for population-specific strategies. A sharp age-related increase in prevalence highlights the need for preventive measures. Furthermore, the high prevalence of frailty among women, illiterate and rural residents indicates the target population for receiving preventive interventions. Lastly, a heterogeneity in frailty prevalence across different States indicates the scope for region-specific programmes.

Bioinformatics analysis of effective biomarkers and immune infiltration in type 2 diabetes with cognitive impairment and aging.

With the increasing prevalence of diabetes mellitus worldwide, type 2 diabetes mellitus (T2D) combined with cognitive impairment and aging has become one of the common and important complications of diabetes mellitus, which seriously affects the quality of life of the patients, and imposes a heavy burden on the patients' families and the society. Currently, there are no special measures for the treatment of cognitive impairment and aging in type 2 diabetes mellitus. Therefore, the search for potential biological markers of type 2 diabetes mellitus combined with cognitive impairment and aging is of great significance for future precisive treatment. We downloaded three gene expression datasets from the GEO database: GSE161355 (related to T2D with cognitive impairment and aging), GSE122063, and GSE5281 (related to Alzheimer's disease). Differentially expressed genes (DEGs) were identified, followed by gene set enrichment analysis (GSEA). A protein-protein interaction (PPI) network was constructed using the STRING database, and the top 15 hub genes were identified using the CytoHubba plugin in Cytoscape. Core genes were ultimately determined using three machine learning methods: LASSO regression, Support Vector Machine Recursive Feature Elimination (SVM-RFE), and Linear Discriminant Analysis (LDA). The diagnostic performance of these genes was assessed using ROC curve analysis and validated in an independent dataset (GSE5281). Regulatory genes related to ferroptosis were screened from the FerrDb database, and their biological functions were further explored through GO and KEGG enrichment analyses. Finally, the CIBERSORT algorithm was used to analyze immune cell infiltration, and the correlation between core genes and immune cell infiltration levels was calculated, leading to the construction of an mRNA-miRNA regulatory network. In the GSE161355 and GSE122063 datasets, 217 common DEGs were identified. GSEA analysis revealed their enrichment in the PI3K-PLC-TRK signaling pathway, TP53 regulation of metabolic genes pathway, Notch signaling pathway, among others. PPI network analysis identified 15 candidate core genes, and further selection using LASSO, LDA, and SVM-RFE machine learning algorithms resulted in 6 core genes: BCL6, TP53, HSP90AA1, CRYAB, IL1B, and DNAJB1. ROC curve analysis indicated that these genes had good diagnostic performance in the GSE161355 dataset, with TP53 and IL1B achieving an AUC of 0.9, indicating the highest predictive accuracy. BCL6, HSP90AA1, CRYAB, and DNAJB1 also had AUCs greater than 0.8, demonstrating moderate predictive accuracy. Validation in the independent dataset GSE5281 showed that these core genes also had good diagnostic performance in Alzheimer's disease samples (AUC > 0.6). Ferroptosis-related analysis revealed that IL1B and TP53 play significant roles in apoptosis and immune response. Immune cell infiltration analysis showed that IL1B is significantly positively correlated with infiltration levels of monocytes and NK cells, while TP53 is significantly negatively correlated with infiltration levels of follicular helper T cells. The construction of the miRNA-mRNA regulatory network suggested that miR-150a-5p might play a key role in the regulation of T2D-associated cognitive impairment and aging by TP53. This study, by integrating bioinformatics and machine learning methods, identified BCL6, TP53, HSP90AA1, CRYAB, IL1B, and DNAJB1 as potential diagnostic biomarkers for T2D with cognitive impairment and aging, with a particular emphasis on the significance of TP53 and IL1B in immune cell infiltration. These findings not only enhance our understanding of the molecular mechanisms linking type 2 diabetes to cognitive impairment and aging, providing new targets for early diagnosis and treatment, but also offer new directions and targets for basic research.

Mediating role of accelerated aging in the association between depression and mortality risk: findings from NHANES.

OBJECTIVE: To investigate the association between depression, accelerated biological aging, and mortality risk, and to assess whether accelerated aging mediates the relationship between major depression and mortality risk. METHODS: A prospective cohort of 12,761 participants aged 20 years or older from the 2005-2010 cycle of the National Health and Nutrition Examination Survey (NHANES) was analyzed. Depression was assessed using the Patient Health Questionnaire-9 (PHQ-9), with scores of ≥ 10 indicating major depression. Accelerated biological aging was measured using phenotypic age acceleration (PhenoAgeAccel). Multivariable linear regression models and subgroup analyses were used to examine the association between depression and accelerated aging, while weighted multivariable Cox proportional hazards regression models and subgroup analyses assessed the impact of major depression on mortality risk. Mediation analysis was performed to assess whether PhenoAgeAccel mediated the relationship between major depression and mortality outcomes. RESULTS: Among the 12,761 adults, the weighted mean age was 46.6 years, with 48.8% being male, and 6.9% experiencing major depression. The results showed a positive association between major depression and PhenoAgeAccel (ß: 0.61, 95% CI: 0.06-1.16). Over a median follow-up duration of 11.3 years (interquartile range: 9.9-13.1), major depression was associated with increased all-cause mortality (HR: 1.35, 95% CI: 1.13-1.62) and cardiovascular mortality (HR: 1.73, 95% CI: 1.18-2.54). However, the relationship with cancer mortality was not statistically significant after full adjustment for confounding factors. The mediation analysis further revealed that PhenoAgeAccel accounted for 10.32% and 5.12% of the associations between major depression and all-cause mortality, and cardiovascular mortality, respectively. CONCLUSION: Depression is associated with accelerated aging and contributes to increased all-cause and cardiovascular mortality. Accelerated aging partially mediates the association between major depression and mortality risk. Our findings highlight the urgent need to incorporate mental health care into public health strategies to delay population aging and reduce mortality risk.

The association between BMI and cognition in India: data from the Longitudinal Aging Study in India (LASI).

BACKGROUND: High body-mass index (BMI) is an established risk factor for late-life cognitive impairment and dementia, but most evidence comes from high-income contexts. Existing evidence from cross-sectional data in low- and middle-income settings is inconsistent, and many studies do not adequately address potential sources of bias. METHODS: We used data from Wave 1 of the Longitudinal Aging Study in India (LASI) (analytic N = 56,753) to estimate the association between BMI categories and cognitive functioning among older adults aged 45 + years using survey-weighted linear regression models stratified by gender and controlling for potential confounders including demographic factors, socio-economic status (SES) characteristics, and health-related behaviors. To probe potential sources of bias, including residual confounding and reverse causation, we used weighting and trimming methods, sample restriction, and explored effect modification. RESULTS: In fully adjusted models, relative to normal BMI underweight BMI was associated with lower cognitive scores (Men: -0.16 SD difference, 95% CI -0.18, -0.13; Women: -0.12 SD, -0.15, -0.10). Overweight and obesity were associated with higher cognitive scores in both men (overweight: 0.09; 0.07, 0.12, obese: 0.10; 0.05, 0.15) and women (overweight: 0.09; 0.07-0.12, obese: 0.12; 0.08-0.15). Estimates were similar after weighting and trimming but were attenuated after excluding those with low cognition (≥1 SD below the mean relative to those with similar demographic characteristics). Positive associations between overweight and obese BMI and cognition were attenuated or null in those living in urban settings and those with higher levels of educational attainment. CONCLUSIONS: Underweight BMI is a risk factor for poor cognitive outcomes in adults 45 years and older and may be indicative of poor nutritional status and life-course disadvantage in India. In tandem with existing literature, supplemental analyses and effect modification results indicate that unmeasured confounding and reverse causation may explain the observed positive associations between overweight and obese BMI and cognitive functioning from cross-sectional studies in low- and middle-income settings. Future data with longitudinal follow-up will be helpful to further disentangle biases.

The Nrf2-HO-1 system and inflammaging.

Nrf2 is a master transcriptional regulator of a number of genes involved in the adaptive response to oxidative stress. Among the genes upregulated by Nrf2, heme oxygenase-1 (HO-1) has received significant attention, given that the products of HO-1-induced heme catabolism have well established antioxidant and anti-inflammatory properties. This is evidenced in numerous models of inflammatory and autoimmune disease whereby induction of HO-1 expression or administration of tolerable amounts of HO-1 reaction products can ameliorate disease symptoms. Unsurprisingly, Nrf2 and HO-1 are now considered viable drug targets for a number of conditions. In recent years, the term 'inflammaging' has been used to describe the low-grade chronic inflammation observed in aging/aged cells. Increased oxidative stress is also a key factor associated with aging and there is convincing evidence that Nrf2, not only declines with age, but that Nrf2 and HO-1 can reduce cellular senescence and the senescence-associated secretory phenotype (SASP) which is now considered an underlying driver of age-related inflammatory disease. In this review, we describe the role of oxidative stress in 'inflammaging' and highlight the potential anti-aging properties of the Nrf2-HO-1 system. We also highlight established and newly emerging Nrf2 activators and their therapeutic application in age-related disease.

Exogenous and endogenous formaldehyde-induced DNA damage in the aging brain: mechanisms and implications for brain diseases.

Exogenous gaseous formaldehyde (FA) is recognized as a significant indoor air pollutant due to its chemical reactivity and documented mutagenic and carcinogenic properties, particularly in its capacity to damage DNA and impact human health. Despite increasing attention on the adverse effects of exogenous FA on human health, the potential detrimental effects of endogenous FA in the brain have been largely neglected in current research. Endogenous FA have been observed to accumulate in the aging brain due to dysregulation in the expression and activity of enzymes involved in FA metabolism. Surprisingly, excessive FA have been implicated in the development of neurodegenerative diseases such as Alzheimer's disease (AD), Parkinson's disease (PD), and brain cancers. Notably, FA has the ability to not only initiate DNA double strand breaks but also induce the formation of crosslinks of DNA-DNA, DNA-RNA, and DNA-protein, which further exacerbate the progression of these brain diseases. However, recent research has identified that FA-resistant gene exonuclease-1 (EXO1) and FA scavengers can potentially mitigate FA toxicity, offering a promising strategy for mitigating or repairing FA-induced DNA damage. The present review offers novel insights into the impact of FA metabolism on brain ageing and the contribution of FA-damaged DNA to the progression of neurological disorders.

Advanced paternal age exacerbates neuroinflammation in offspring via m6A modification-mediated intergenerational inheritance.

BACKGROUND: The trend of postponing childbearing age is prevalent worldwide. Advanced paternal age (APA) is associated with adverse pregnancy outcomes and offspring health. However, the underlying mechanism by which paternal aging affects the risk of offspring neuropsychiatric disorders is unclear. Our study aims to explore the behavioral phenotypes and the pathologic epigenetic alterations of APA offspring inherited from aging sperm. METHODS: Behavioral tests, ELISA assay, immunofluorescence and western blotting were performed on offspring mice. Methylated RNA immunoprecipitation sequencing (MeRIP-seq) and RNA immunoprecipitation sequencing (RIP-seq) were used to investigate the modified N6-methyladenosine (m6A) profiles of paternal sperm and offspring hippocampus. Intervention of gene expression by lentivirus and adeno-associated virus in both vivo and vitro examined the potential therapeutic targets of intergenerational inherited neuroinflammation. RESULTS: In our study, APA offspring exhibit cognitive impairment and autism-like behavior. An increase in neuroinflammation in APA offspring is associated with microglial overactivation, which manifests as abnormal morphology and augmented engulfment. MeRIP-seq of F0 sperm and F1 hippocampus reveal that Nr4a2 is hypermethylated with decreased expression in APA offspring involving in synaptic plasticity and microglial function. In addition, Ythdc1, an m6A reader protein, is markedly elevated in aging sperm and remains elevated in adult hippocampus of APA group. Enhanced Ythdc1 recognizes and suppresses the hypermethylated Nr4a2, thereby contributing to the abnormal phenotype in offspring. The overexpression of Ythdc1 triggers microglial activation in vitro and its suppression in the hippocampus of APA progeny alleviates behavioral aberrations and attenuates neuroinflammation. CONCLUSION: Our study provides additional evidence of the abnormal behavioral phenotypes of APA offspring and reveals potential epigenetic inheritance signatures and targeted genes for future research.