Key Signaling Pathways in Aging and Potential Interventions for Healthy Aging

Effect of curcumin on cardiometabolic diseases in the elderly: a systematic review of randomized controlled trials

INTRODUCTION

As people age, the incidence of cardiometabolic diseases rises, negatively impacting their quality of life; therefore, it is important to supplement the diet with compounds that can manage these conditions. Curcumin (Cur), a common dietary spice, may benefit the health of the elderly. This systematic review evaluates Cur's effectiveness in improving cardiometabolic disease symptoms.

METHODS

Relevant studies were identified from searches conducted in Scopus, Embase, and PubMed. The risk of bias was assessed using the Cochrane Risk of Bias 2 (RoB 2) tool.

RESULTS AND DISCUSSION

Seven randomized controlled trials (RCTs) were included. Cur supplementation (CurS) in elderly individuals resulted in significant improvements in several metabolic and inflammatory markers, including reductions in C-reactive protein (CRP) (p=0.03), systolic blood pressure (p=0.04), fasting blood sugar (p=0.02), and HOMA-IR (p=0.01) compared with controls. Additionally, a significant decrease in triglyceride levels (p=0.04) and an increase in HDL (p=0.03) were observed. However, effects on other cardiovascular indices were inconsistent across the studies.

CONCLUSIONS

These findings suggest that Cur may serve as an adjunctive therapy for age-related cardiometabolic diseases; however, variability in outcomes and protocols limits the ability to make broad recommendations. Future research should focus on large, well-powered RCTs with standardized dosing, formulations, and treatment durations, including long-term follow-up to assess sustained efficacy and delayed adverse effects. Comprehensive safety monitoring and detailed documentation of supplement composition and patient characteristics are also needed to clarify heterogeneity and identify those at higher risk for complications.

Geroprotective applications of oleuropein and hydroxytyrosol through the hallmarks of ageing

Geroprotectors are compounds that target the underlying mechanisms of ageing to delay the onset of age-related diseases and extend both lifespan and health span. As ageing is driven by the accumulation of cellular damage, DNA instability, epigenetic changes, mitochondrial dysfunction, and chronic inflammation, the concept of geroprotection focuses on compounds that can mitigate these processes. Oleuropein (OLE) and its derivative hydroxytyrosol (HT), both phenolic molecules derived from Olea europaea (olive tree), have gained significant attention as potential geroprotectors due to their potent antioxidant and anti-inflammatory properties. These phytochemicals, central to the Mediterranean diet, activate key molecular pathways such as nuclear factor erythroid 2-related factor 2, reducing oxidative stress and modulating inflammatory responses. Through these mechanisms, OLE and HT help counteract inflammageing, a critical factor in age-related dysfunction. This review highlights the role of OLE and HT as geroprotective agents, emphasising their ability to target the hallmarks of ageing and their potential to improve health span by slowing the progression of age-related conditions. With proven efficacy in various biological models, these compounds represent promising tools in the ongoing search for strategies to enhance the quality of life in ageing populations.

Effects of aging and resistance exercise on muscle strength, physiological properties, longevity proteins, and telomere length in SAMP8 mice

Skeletal muscle aging, characterized by progressive declines in muscle mass and strength, correlates with reduced quality of life and increased mortality. Resistance exercise is known to be critical for maintaining skeletal muscle health. This study investigated the effects of aging and resistance exercise on muscle strength, physiological properties, longevity proteins, and telomere length in mice. Twenty-eight-week-old senescence-accelerated mouse prone 8 (SAMP8) mice were used as a model for muscle aging, with senescence-accelerated mouse resistant 1 (SAMR1) mice serving as healthy controls. The mice underwent a 12-week regimen of ladder-climbing training, a form of resistance exercise, performed three days per week. After the training, muscle strength and muscle weight were measured. Levels of the longevity proteins adenosine monophosphate-activated kinase (AMPK), mammalian target of rapamycin (mTOR), and sirtuin 1 (SIRT1) were assessed via western blotting, and telomere length was evaluated by qPCR. SAMP8 mice exhibited significantly lower muscle mass and strength than SAMR1 mice, while resistance exercise attenuated these deficits in SAMP8 mice. SAMP8 mice showed elevated AMPK phosphorylation and SIRT1 levels compared to SAMR1 mice; resistance exercise normalized AMPK phosphorylation levels to approximate those of SAMR1 mice. mTOR activity was significantly reduced in SAMP8 mice but tended to be restored by resistance exercise. Telomere length remained unchanged in SAMP8 mice after resistance exercise compared to their sedentary controls. In conclusion, aging reduces muscle function and disrupts levels of longevity proteins. Resistance exercise mitigates these effects by improving muscle function and restoring molecular balance.

Intermittent fasting applied in combination with astaxanthin alleviates D-galactose-induced aging in rats: Comparison in oxidative stress, immune response, and metabolomics

Effective anti-aging strategies involving dietary restriction and antioxidant supplementation are gaining increasing research attention, while the health effects of their combined intervention are rarely reported. In this study, for the first time, we investigated the anti-aging effects and underlying mechanisms of intermittent fasting (IF), astaxanthin (AX), and their combination in D-galactose-induced aging rats. Our results demonstrated that these three treatments effectively inhibited malondialdehyde levels and improved the activity of endogenous antioxidant enzymes in the brain, liver, and serum of aging rats. Simultaneously, the combination of IF and AX had a synergistic effect on the recovery of brain mitochondrial injury as evidenced by permeability transition pore openness, membrane potential, respiratory chain complex enzyme activity, and cortical and hippocampal lesions. Notably, the combination significantly increased the levels of Immunoglobulin M (55.66 ± 3.23%), immunoglobulin G (34.41 ± 2.65%), and IL-2 (23.49 ± 1.78%) compared with the model group. Moreover, AX reduced the accumulation of pro-inflammatory factor IL-6 (23.06 ± 2.02%), while the combination induced more remarkable reduction in the accumulation of IL-1β (35.92 ± 3.06%) in the serum. Considering the serum metabolomics analysis, we hypothesized that IF and AX played a positive role in the regulation of the nervous system, which was associated with the differential metabolites lysope 16:0, N-Acety-L-tyrosine, and L-Alanyl-L-Lysine. This research reveals that the combination therapy provided synergistic anti-aging efficacy by enhancing resistance to oxidative stress, ameliorating mitochondrial dysfunction, and restoring the immune system. These findings might have significant implications for further studies on the exploration of effective anti-aging therapy.

SPRY1 regulates macrophage M1 polarization in skin aging and melanoma prognosis

INTRODUCTION

Skin aging is a complex, multifactorial process involving cellular damage, inflammation, and increased susceptibility to diseases. Despite its importance, the role of SPRY1 in skin aging remains poorly understood. This study aims to investigate the function of SPRY1 in skin aging, particularly its impact on macrophage M1 polarization, and explore its potential as a therapeutic target for mitigating skin aging and melanoma.

METHODS

Bioinformatics analyses were performed using datasets from the GTEx and GEO databases, alongside in vitro cellular experiments. These included Weighted Gene Co-expression Network Analysis (WGCNA), single-cell sequencing, and various cellular assays in RAW264.7 murine monocyte/macrophage leukemia cells and NIH/3T3 mouse skin fibroblasts. The assays comprised gene transfection, Cell Counting Kit-8 (CCK-8) assays, quantitative real-time PCR (qRT-PCR), and measurements of reactive oxygen species (ROS) and superoxide dismutase (SOD) activity.

RESULTS

SPRY1 was identified as a key gene within modules linked to skin aging. Single-cell sequencing revealed its enrichment in macrophages and keratinocytes. Knockdown of SPRY1 in RAW264.7 cells resulted in a shift from M1 to M2 macrophage polarization, reduced oxidative stress, and decreased expression of inflammatory markers. In NIH/3T3 cells, SPRY1 knockdown reduced cell viability and lowered the expression of inflammatory genes. Additionally, SPRY1 expression was downregulated in melanoma, and its reduced levels were associated with poorer survival outcomes.

CONCLUSIONS

SPRY1 accelerates skin aging by promoting macrophage M1 polarization and may serve as a promising therapeutic target. Future research should focus on in vivo validation and further exploration of its regulatory networks to develop novel treatments.

Effect of oral resveratrol-loaded nanoliposomes on hyperlipidemia via toll-like receptor 3 and TIR domain-containing adaptor inducing interferon-β protein expression in an animal model

Hyperlipidemia, a critical risk factor for various health conditions, necessitates innovative therapeutic strategies. Investigating the effectiveness of liposomal formulations in managing hyperlipidemia is essential. Resveratrol (RES)-loaded nanoliposomes present a promising new approach for hyperlipidemia treatment. In this study, we investigated the anti-hyperlipidemic potential of RES-loaded nanoliposomes in high-fat diet (HFD)-fed rats. The nanoliposomes were prepared using a thin-film hydration method. According to transmission electron microscopy (TEM) and dynamic light scattering (DLS) results, the mean size of prepared RES-loaded nanoliposomes were about 42 nm and 68 nm, respectively, with a zeta potential of -65.6 mV. The entrapment efficiency and loading content were 83.78% and 14.25%, respectively. Additionally, the RES-loaded nanoliposomes exhibited controlled release kinetics compared to the free RES form. Moreover, in a hyperlipidemic rat model induced by an HFD, orally administered RES-loaded nanoliposomes significantly reduced total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), very low-density lipoprotein cholesterol (VLDL-C), and triglycerides (TG), while concurrently increasing high-density lipoprotein cholesterol (HDL-C) levels. Additionally, liver damage induced by HFD was alleviated by RES-loaded nanoliposomes. The expression levels of Toll-like receptor 3 (TLR3) and TIR domain-containing adaptor-inducing interferon-β (TRIF) were assessed using fluorescence immunohistochemistry. Notably, RES-loaded nanoliposomes significantly reduced the expression of these protein. The effect of RES-loaded nanoliposomes was measured on body weight of HFD rats, demonstrting RES-loaded nanoliposomes hold promise for weight management. These findings underscore the potential of RES-loaded nanoliposomes as a safe and effective therapeutic option for hyperlipidemia.

Mechanisms and early efficacy data of caloric restriction and caloric restriction mimetics in neurodegenerative disease

Neurodegenerative disorders (NDDs) have been prevalent for more than a decade, and the number of individuals affected per year has increased exponentially. Among these NDDs, Alzheimer's disease, which causes extreme cognitive impairment, and Parkinson's disease, characterized by impairments in motor activity, are the most prevalent. While few treatments are available for clinical practice, they have minimal effects on reversing the neurodegeneration associated with these debilitating diseases. Lifestyle modifications and dietary choices are emerging and promising approaches to combat these disorders. Of the lifestyle changes that one could adopt, a major habit is caloric restriction. Caloric restriction (CR) is a lifestyle modification in which the amount of calories ingested is reduced to a significant amount without resulting in malnutrition. However, maintaining such a lifestyle is challenging. As alternatives, certain compounds have been recognized to mimic the effects produced by CR. These compounds are called caloric restriction mimetics (CRMs). Among these compounds, some have been designated established CRMs, namely, resveratrol, metformin, and rapamycin, whereas several other candidates are termed potential CRMs because of a lack of conclusive evidence of their effects. The potential CRMs discussed in this review are quercetin, chrysin, astragalin, apigenin, curcumin, epigallocatechin-3-gallate, and NAD+ precursors. This review aims to provide an overview of these CRMs' effectiveness in preventing neurodegenerative disorders associated with aging. Moreover, we highlight the clinical relevance of these compounds by discussing in detail the results of clinical trials on them.

Proteomic analysis across aged tissues reveals distinct signatures and the crucial involvement of midgut barrier function in the regulation of aging

The process of aging is a natural phenomenon characterized by gradual deterioration in biological functions and systemic homeostasis, which can be modulated by both genetic and environmental factors. Numerous investigations conducted on model organisms, including nematodes, flies, and mice, have elucidated several pivotal aging pathways, such as insulin signaling and AMPK signaling. However, it remains uncertain whether the regulation of the aging process is uniform or diverse across different tissues and whether manipulating the same aging factor can result in consistent outcomes in various tissues. In this study, we utilize the Drosophila organism to investigate tissue-specific proteome signatures during the aging process. Although distinct proteins undergo changes in aged tissues, certain common altered functional networks are constituently identified across different tissues, including the decline of the mitochondrial ribosomal network, autophagic network, and anti-ROS defense networks. Furthermore, downregulation of insulin receptor (InR) in the midguts, muscle, and central nervous system (CNS) of flies leads to a significant extension in fly lifespans. Notably, despite manipulating the same aging gene InR, diverse alterations in proteins are observed across different tissues. Importantly, knockdown of InR in the midguts leads to a distinct proteome compared with other tissues, resulting in enhanced actin nucleation and glutathione metabolism, while attenuating age-related elevation of serine proteases. Consequently, knockdown of InR results in rejuvenation of the integrity of the midgut barrier and augmentation of anti-ROS defense capabilities. Our findings suggest that the barrier function of the midgut plays a pivotal role in defending against aging, underscoring the paramount importance of maintaining optimal gut physiology to effectively delay the aging process. Moreover, when considering age-related changes across various tissues, it is more reasonable to identify functional networks rather than focusing solely on individual proteins.

Garcinia flavonoids for healthy aging: Anti-senescence mechanisms and cosmeceutical applications in skin care

Cellular senescence, the irreversible arrest of cell division, is a hallmark of aging and a key contributor to age-related disorders. Targeting senescent cells represents a promising therapeutic approach to combat these ailments. This review explores the potential of Garcinia species, a genus rich in flavonoids with established antioxidant and anti-inflammatory properties, as a source of natural anti-senescence agents. We investigate the intricate connections between aging, cellular senescence, and oxidative stress, highlighting the detrimental effects of free radicals on cellular health. Furthermore, we analyze the diverse array of flavonoids identified within Garcinia and their established cellular mechanisms. We critically evaluate the emerging evidence for the anti-senescence potential of flavonoids in general and the limited research on Garcinia flavonoids in this context. By identifying existing knowledge gaps and paving the way for future research, this review underscores the exciting potential of Garcinia flavonoids as natural anti-senescence agents. These agents hold promise for not only promoting healthy aging but also for the development of cosmeceutical products that combat the visible signs of aging.

Prevalence of participation of Brazilian aged people in Advanced Activities of Daily Living and associated factors

OBJECTIVE

To estimate the prevalence of participation of aged Brazilians in Advanced Activities of Daily Living and associated factors.

METHODS

Cross-sectional study developed with secondary data from the National Health Survey. Aged people (60 years old or older) were included. The dependent variable consisted of questions from the National Health Survey regarding the performance of Advanced Activities of Daily Living, related to work, leisure, and social participation. Descriptive analysis, Rao-Scott test, and standardized residual analysis were performed. Effect measures were calculated using simple and multiple multinominal logistic regression models.

RESULTS

The majority of Brazilian aged people have low participation in Advanced Activities of Daily Living. Aged males, between 60 and 69 years old, white, from the Southeast, South and Central-West regions, with higher educational levels, absence of chronic diseases, monthly alcohol consumption, regular physical activity, frequent intake of vegetables, use of glasses and independence when moving, were more likely to perform Advanced Activities of Daily Living.

CONCLUSION

These results reinforce the significant influence of demographic, socioeconomic, clinical factors, linked to lifestyle and intrinsic capacity in the execution of Advanced Activities of Daily Living. In a broader sense, such discoveries can strengthen public policies for active and healthy aging.

Full-length direct RNA sequencing reveals extensive remodeling of RNA expression, processing and modification in aging Caenorhabditis elegans

Organismal aging is marked by decline in cellular function and anatomy, ultimately resulting in death. To inform our understanding of the mechanisms underlying this degeneration, we performed standard RNA sequencing (RNA-seq) and Oxford Nanopore Technologies direct RNA-seq over an adult time course in Caenorhabditis elegans. Long reads allowed for identification of hundreds of novel isoforms and age-associated differential isoform accumulation, resulting from alternative splicing and terminal exon choice. Genome-wide analysis reveals a decline in RNA processing fidelity. Finally, we identify thousands of inosine and hundreds of pseudouridine edits genome-wide. In this first map of pseudouridine modifications for C. elegans, we find that they largely reside in coding sequences and that the number of genes with this modification increases with age. Collectively, this analysis discovers transcriptomic signatures associated with age and is a valuable resource to understand the many processes that dictate altered gene expression patterns and post-transcriptional regulation in aging.

Recognition of mild cognitive impairment in older adults using a polynomial regression model based on prefrontal cortex hemoglobin oxygenation

AIM

This study employed a three-minute game-based intelligence test (GBIT) to create a hemoglobin polynomial regression model for early identification of mild cognitive impairment (MCI) in older adults.

METHODS

210 older adult participants were recruited from community centers in the central region of Taichung City. Working memory (WM) performance in older adults was assessed during GBIT, while hemoglobin responses were measured by near-infrared spectroscopy (NIRS). Variables included oxyhemoglobin (O2Hb) and deoxyhemoglobin (HHb). Data sequences underwent a fitting procedure using a transformed cubic polynomial function. The transformed coefficients were used as predictors of a logistic regression model to recognize MCI in older adults.

RESULTS

This study confirmed the relationship between age and cognitive performance. The findings demonstrate that the NIRS cubic polynomial function trends during the GBIT test showed significant changes in older adults, increasing with age. Logistic regression analysis identified age and the orientation (coefficient a) of HHb as the main factors for recognizing MCI. The model achieved an overall precision of 83.33 % (sensitivity = 75.00 %; specificity = 84.68 %) with the formula: ln (Odds [MCI]) = -1.64 + 0.57 × HHb_a + 1.40 × age.

CONCLUSIONS

NIRS hemoglobin response characteristics during GBIT may serve as an efficient indicator of MCI in older adults. These findings may advance the field of cognitive health evaluation, resulting in earlier detection of cognitive deterioration in older adults.

Impact of coffee intake on human aging: Epidemiology and cellular mechanisms

The conception of coffee consumption has undergone a profound modification, evolving from a noxious habit into a safe lifestyle actually preserving human health. The last 20 years also provided strikingly consistent epidemiological evidence showing that the regular consumption of moderate doses of coffee attenuates all-cause mortality, an effect observed in over 50 studies in different geographic regions and different ethnicities. Coffee intake attenuates the major causes of mortality, dampening cardiovascular-, cerebrovascular-, cancer- and respiratory diseases-associated mortality, as well as some of the major causes of functional deterioration in the elderly such as loss of memory, depression and frailty. The amplitude of the benefit seems discrete (17 % reduction) but nonetheless corresponds to an average increase in healthspan of 1.8 years of lifetime. This review explores evidence from studies in humans and human tissues supporting an ability of coffee and of its main components (caffeine and chlorogenic acids) to preserve the main biological mechanisms responsible for the aging process, namely genomic instability, macromolecular damage, metabolic and proteostatic impairments with particularly robust effects on the control of stress adaptation and inflammation and unclear effects on stem cells and regeneration. Further studies are required to detail these mechanistic benefits in aged individuals, which may offer new insights into understanding of the biology of aging and the development of new senostatic strategies. Additionally, the safety of this lifestyle factor in the elderly prompts a renewed attention to recommending the maintenance of coffee consumption throughout life as a healthy lifestyle and to further exploring who gets the greater benefit with what schedules of which particular types and doses of coffee.

Elucidation of anti-human melanoma and anti-aging mechanisms of compounds from green seaweed Caulerpa racemosa

Human melanoma is linked with aging-related disorders, prompting interest in the development of functional foods derived from natural ingredients to mitigate its incidence. Molecules in green seaweeds such as Caulerpa racemosa can serve this purpose due to their anti-tumor and anti-inflammatory properties. A previous work study compounds profiling has been carried out, and in this research the molecular docking studies targeting receptors associated with melanoma (GRP78, IRE1, BRAF) and aging (mTOR, AMPK, SIRT1) identified four promising compound in an extract of C. racemosa. The current study aims to the mechanism of those compounds at a cellular level using the human A375 (BRAF-V600E mutation) and A375 and B16-F10 cell lines. The MTT assay was used to evaluate the potential of GSCRE compounds against A375 and B16-F10 cell lines, with comparisons made to normal HDFa cell lines. Results indicated that compound C2, also known as Caulersin, demonstrated a significantly different ∆G affinity binding score compared to the control drug Dabrafenib. GSCRE crude extract, particularly C2, showed potential in modulating mTOR, AMPK, and SIRT1 pathways and downregulating GRP78, IRE1, and BRAF signaling (p < 0.05). Interestingly, C2 was less effective in suppressing A375 and B16-F10 cell lines (LD50 C2 < LD50 Dabrafenib/control), with its LD50 value nearly matching that of the Trametinib control in B16-F10 cell lines. Consequently, GSCRE, especially C2 or Caulersin, shows promise as a new molecule for developing functional foods to combat aging and human melanoma. However, further in vivo studies and clinical trials are necessary to confirm these findings.

Hypoxia and aging: molecular mechanisms, diseases, and therapeutic targets

Aging is a complex biological process characterized by the gradual decline of cellular functions, increased susceptibility to diseases, and impaired stress responses. Hypoxia, defined as reduced oxygen availability, is a critical factor that influences aging through molecular pathways involving hypoxia-inducible factors (HIFs), oxidative stress, inflammation, and epigenetic modifications. This review explores the interconnected roles of hypoxia in aging, highlighting how hypoxic conditions exacerbate cellular damage, promote senescence, and contribute to age-related pathologies, including cardiovascular diseases, neurodegenerative disorders, cancer, metabolic dysfunctions, and pulmonary conditions. By examining the molecular mechanisms linking hypoxia to aging, we identify key pathways that serve as potential therapeutic targets. Emerging interventions such as HIF modulators, antioxidants, senolytics, and lifestyle modifications hold promise in mitigating the adverse effects of hypoxia on aging tissues. However, challenges such as the heterogeneity of aging, lack of reliable biomarkers, and safety concerns regarding hypoxia-targeted therapies remain. This review emphasizes the need for personalized approaches and advanced technologies to develop effective antiaging interventions. By integrating current knowledge, this review provides a comprehensive framework that underscores the importance of targeting hypoxia-induced pathways to enhance healthy aging and reduce the burden of age-related diseases.

The Potential Impact of SGLT2-I in Diabetic Foot Prevention: Promising Pathophysiologic Implications, State of the Art, and Future Perspectives-A Narrative Review

The impact of diabetic foot (DF) on the healthcare system represents a major public health problem, leading to a considerable clinical and economic burden. The factors contributing to DF's development and progression are strongly interconnected, including metabolic causes, neuropathy, arteriopathy, and inflammatory changes. Sodium-glucose cotransporter 2 inhibitors (SGLT2-i), novel oral hypoglycemic drugs used as an adjunct to standard treatment, have recently changed the pharmacological management of diabetes. Nevertheless, data about the risk of limb amputation, discordant and limited to canagliflozin, which is currently avoided in the case of peripheral artery disease, have potentially discouraged the design of specific studies targeting DF. There is good evidence for the single immunomodulatory, neuroprotective, and beneficial vascular effects of SGLT2-i. Still, there is no clinical evidence about the early use of SGLT2-i in diabetic foot due to the lack of longitudinal and prospective studies proving the effect of these drugs without confounders. This narrative review aims to discuss the main evidence about the impact of SGLT2-i on the three complications of diabetes implicated in the development of DF, the state of the art, and the potential future implications.

CRISPR-Cas9 mediated d3GHR knockout in HEK293 cells: Revealing the longevity associated isoform stress resilience

The Growth Hormone Receptor (GHR) gene encodes a protein that is essential for mediating the biological effects of growth hormone (GH). A series of molecular events are set off when GH binds to its receptor, resulting in a variety of physiological reactions linked to development, growth, and metabolism. Recently a particular genetic variation, within the GHR gene that is labeled as the "d3GHR," which lacks exon 3 was associated with longevity. This specific deletion isoform was connected to changes in the structure of the GHR protein, which may have an impact on the GHR's function. To test in vitro the advantage of the d3 carrier that may link to longevity, we employed the CRISPR/Cas9 technique to produce two isoforms: the homozygotes isoform (d3/d3) and the heterozygotes isoform (d3/fl) using HEK293 cell line. The CRISPR editing effectiveness was >85 %, indicating that we had successfully built the Cas9-gRNA complex that is appropriate for the GHR gene. The viability of the resulted isoform cells was examined under three environmental stressors that mimic some aging processes. In addition, we examined the GHR signaling pathway by selecting potential downstream genes in the GHR signaling cascade. The results show that heterozygotes cells demonstrated higher survival rates under UV radiation compared with the WT cells (87 % compared with 67 % for the WT cells when exposed to 2 min of UV radiation), and in fasting conditions, the d3GHR cells showed a 15 % greater viability than the WT cells. Moreover, the baseline expression levels (without intervention) of the IGF1 and JAK/STAT genes signaling pathways significantly declined in the homozygotes cells compared with the WT (p < 0.05). This noteworthy finding might offer a practical approach to test illness prevention and give the scientific community critical new insights on mechanism associated with lifespan.

Mechanisms of Senescence and Anti-Senescence Strategies in the Skin

The skin is the layer of tissue that covers the largest part of the body in vertebrates, and its main function is to act as a protective barrier against external environmental factors, such as microorganisms, ultraviolet light and mechanical damage. Due to its important function, investigating the factors that lead to skin aging and age-related diseases, as well as understanding the biology of this process, is of high importance. Indeed, it has been reported that several external and internal stressors contribute to skin aging, similar to the aging of other tissues. Moreover, during aging, senescent cells accumulate in the skin and express senescence-associated factors, which act in a paracrine manner on neighboring healthy cells and tissues. In this review, we will present the factors that lead to skin aging and cellular senescence, as well as ways to study senescence in vitro and in vivo. We will further discuss the adverse effects of the accumulation of chronic senescent cells and therapeutic agents and tools to selectively target and eliminate them.

DNA methylation correlates of chronological age in diverse human tissue types

BACKGROUND

While the association of chronological age with DNA methylation (DNAm) in whole blood has been extensively studied, the tissue-specificity of age-related DNAm changes remains an active area of research. Studies investigating the association of age with DNAm in tissues such as brain, skin, immune cells, fat, and liver have identified tissue-specific and non-specific effects, thus, motivating additional studies of diverse human tissue and cell types.

RESULTS

Here, we performed an epigenome-wide association study, leveraging DNAm data (Illumina EPIC array) from 961 tissue samples representing 9 tissue types (breast, lung, colon, ovary, prostate, skeletal muscle, testis, whole blood, and kidney) from the Genotype-Tissue Expression (GTEx) project. We identified age-associated CpG sites (false discovery rate < 0.05) in 8 tissues (all except skeletal muscle, n = 47). This included 162,002 unique hypermethylated and 90,626 hypomethylated CpG sites across all tissue types, with 130,137 (80%) hypermethylated CpGs and 74,703 (82%) hypomethylated CpG sites observed in a single tissue type. While the majority of age-associated CpG sites appeared tissue-specific, the patterns of enrichment among genomic features, such as chromatin states and CpG islands, were similar across most tissues, suggesting common mechanisms underlying cellular aging. Consistent with previous findings, we observed that hypermethylated CpG sites are enriched in regions with repressed polycomb signatures and CpG islands, while hypomethylated CpG sites preferentially occurred in non-CpG islands and enhancers. To gain insights into the functional effects of age-related DNAm changes, we assessed the correlation between DNAm and local gene expression changes to identify age-related expression quantitative trait methylation (age-eQTMs). We identified several age-eQTMs present in multiple tissue-types, including in the CDKN2A, HENMT1, and VCWE regions.

CONCLUSION

Overall, our findings will aid future efforts to develop biomarkers of aging and understand mechanisms of aging in diverse human tissue types.

The clinical antiprotozoal drug nitazoxanide and its metabolite tizoxanide extend Caenorhabditis elegans lifespan and healthspan

The drugs extending healthspan in clinic have always been searched. Nitazoxanide is an FDA-approved clinical antiprotozoal drug. Nitazoxanide is rapidly metabolized to tizoxanide after absorption in vivo. Our previous studies find that nitazoxanide and its metabolite tizoxanide induce mild mitochondrial uncoupling and activate cellular AMPK, oral nitazoxanide protects against experimental hyperlipidemia, hepatic steatosis, and atherosclerosis. Here, we demonstrate that both nitazoxanide and tizoxanide extend the lifespan and healthspan of Caenorhabditis elegans through Akt/AMPK/sir 2.1/daf16 pathway. Additionally, both nitazoxanide and tizoxanide improve high glucose-induced shortening of C. elegans lifespan. Nitazoxanide has been a clinical drug with a good safety profile, we suggest that it is a novel anti-aging drug.

Full-length direct RNA sequencing reveals extensive remodeling of RNA expression, processing and modification in aging Caenorhabditis elegans

Organismal aging is marked by decline in cellular function and anatomy, ultimately resulting in death. To inform our understanding of the mechanisms underlying this degeneration, we performed standard RNA sequencing and Nanopore direct RNA sequencing over an adult time course in Caenorhabditis elegans. Long reads allowed for identification of hundreds of novel isoforms and age-associated differential isoform accumulation, resulting from alternative splicing and terminal exon choice. Genome-wide analysis reveals a decline in RNA processing fidelity and a rise in inosine and pseudouridine editing events in transcripts from older animals. In this first map of pseudouridine modifications for C. elegans, we find that they largely reside in coding sequences and that the number of genes with this modification increases with age. Collectively, this analysis discovers transcriptomic signatures associated with age and is a valuable resource to understand the many processes that dictate altered gene expression patterns and post-transcriptional regulation in aging.

Hematopoietic aging: Cellular, molecular, and related mechanisms

ABSTRACT

Aging is accompanied by significant inhibition of hematopoietic and immune system function and disruption of bone marrow structure. Aging-related alterations in the inflammatory response, immunity, and stem cell niches are at the root of hematopoietic aging. Understanding the molecular mechanisms underlying hematopoietic and bone marrow aging can aid the clinical treatment of aging-related diseases. In particular, it is unknown how the niche reprograms hematopoietic stem cells (HSCs) in an age-dependent manner to maintain normal hematopoiesis in elderly individuals. Recently, specific inhibitors and blood exchange methods have been shown to reshape the hematopoietic niche and reverse hematopoietic aging. Here, we present the latest scientific discoveries related to hematopoietic aging and hematopoietic system rejuvenation, discuss the relationships between hematopoietic niche aging and HSC aging, and describe related studies on stem cell-mediated regulation of hematopoietic aging, aiming to provide new ideas for further study.

Understanding the Impact of the Sirtuin 1 (SIRT1) Gene on Age-related Macular Degeneration: A Comprehensive Study

Age-related macular degeneration (AMD) is a prevalent and incurable condition affecting the central retina and posing a significant risk to vision, particularly in individuals over the age of 60. As the global population ages, the prevalence of AMD is expected to rise, leading to substantial socioeconomic impacts and increased healthcare costs. The disease manifests primarily in two forms, neovascular and non-neovascular, with genetic, environmental and lifestyle factors playing a pivotal role in disease susceptibility and progression. This review article involved conducting an extensive search across various databases, including Google Scholar, PubMed, Web of Science, ScienceDirect, Scopus and EMBASE, to compile relevant case-control studies and literature reviews from online published articles extracted using search terms related to the work. SIRT1, a key member of the sirtuin family, influences cellular processes such as ageing, metabolism, DNA repair and stress response. Its dysregulation is linked to retinal ageing and ocular conditions like AMD. This review discusses the role of SIRT1 in AMD pathology, its association with genetic variants and its potential as a biomarker, paving the way for targeted interventions and personalised treatment strategies. In addition, it highlights the findings of case-control studies investigating the relationship between SIRT1 gene polymorphisms and AMD risk. These studies collectively revealed a significant association between certain SIRT1 gene variants and AMD risk. Further studies with larger sample sizes are required to validate these findings. As the prevalence of AMD grows, understanding the role of SIRT1 and other biomarkers becomes increasingly vital for improving diagnosis, treatment and, ultimately, patient outcomes.

DEHP and DINP accelerate aging effects in male and female of Drosophila melanogaster depend on AKT/FOXO pathway

Phthalates are commonly used as plasticizers. Numerous studies have focused on endocrine, reproductive, and developmental toxicity of phthalates exposure to male organisms. In recent years, some studies looking into the aging effects of phthalates exposure in D. melanogaster showed discrepant results. In this study, we compared the different concentrations of Di(2-ethylhexyl) phthalate (DEHP) and di-isononyl phthalate (DINP) for acute and chronic treatment for different gender D. melanogaster and explored the potential mechanism of DEHP and DINP exposure. The results showed that acute exposure to DEHP or DINP at a high dose significantly decreased the lifespan of female and male D. melanogaster under HFD stress. Chronic exposure significantly decreased the lifespan of flies in all exposure groups except for the low-dose DINP exposure female group. Among them, in the normal feeding group, we found that female flies seemed to be more resistant to DEHP or DINP exposure. Meanwhile, the locomotion ability and fertility of flies exhibited a dose-dependent decline. Furthermore, phthalates did not significantly reduce the lifespan or health status of akt and foxo mutant flies in the mutant fly assays, and real-time quantitative-PCR (q-PCR) data revealed akt and foxo significant change with 10 μM DEHP or DINP treatment. This suggests that akt and foxo played a role in the process by which DEHP and DINP caused age-related declines in D. melanogaster.

Cardiac cell senescence: molecular mechanisms, key proteins and therapeutic targets

Cardiac aging, particularly cardiac cell senescence, is a natural process that occurs as we age. Heart function gradually declines in old age, leading to continuous heart failure, even in people without a prior history of heart disease. To address this issue and improve cardiac cell function, it is crucial to investigate the molecular mechanisms underlying cardiac senescence. This review summarizes the main mechanisms and key proteins involved in cardiac cell senescence. This review further discusses the molecular modulators of cellular senescence in aging hearts. Furthermore, the discussion will encompass comprehensive descriptions of the key drugs, modes of action and potential targets for intervention in cardiac senescence. By offering a fresh perspective and comprehensive insights into the molecular mechanisms of cardiac senescence, this review seeks to provide a fresh perspective and important theoretical foundations for the development of drugs targeting this condition.

Reduced protein intake and aging affects the sustainment of hematopoiesis by impairing bone marrow mesenchymal stem cells

Protein malnourishment (PM) is common among the elderly, but how aging and PM impact hematopoiesis is not fully understood. This study aimed to assess how aging and PM affect the hematopoietic regulatory function of bone marrow (BM) mesenchymal stem cells (MSCs). Young and aged male C57BL/6J mice were fed with normoproteic or hypoproteic diets and had their nutritional, biochemical, and hematological parameters evaluated. BM MSCs were characterized and had their secretome, gene expression, autophagy, reactive oxygen species production (ROS), and DNA double-stranded breaks evaluated. The modulation of hematopoiesis by MSCs was assayed using in vitro and in vivo models. Lastly, BM invasiveness and mice survival were evaluated after being challenged with leukemic cells of the C1498 cell line. Aging and PM alter biochemical parameters, changing the peripheral blood and BM immunophenotype. MSC autophagy was affected by aging and the frequencies for ROS and DNA double-stranded breaks. Regarding the MSCs' secretome, PM and aging affected CXCL12, IL-6, and IL-11 production. Aging and PM up-regulated Akt1 and PPAR-γ while down-regulating Cdh2 and Angpt-1 in MSCs. Aged MSCs increased C1498 cell proliferation while reducing their colony-forming potential. PM and aging lowered mice survival, and malnourishment accumulated C1498 cells at the BM. Finally, aged and/or PM MSCs up-regulated Sox2, Nanog, Pou5f1, and Akt1 expression while down-regulating Cdkn1a in C1498 cells. Together, aging and PM can induce cell-intrinsic shifts in BM MSCs, creating an environment that alters the regulation of hematopoietic populations and favoring the development of malignant cells.

Risk Polymorphisms of FNDC5, BDNF, and NTRK2 and Poor Education Interact and Aggravate Age-Related Cognitive Decline

Cognitive abilities tend to decline with aging, with variation between individuals, and many studies seek to identify genetic biomarkers that more accurately anticipate risks related to pathological aging. We investigated the influence of BDNF, NTRK2, and FNDC5 single nucleotide polymorphisms (SNPs) on the cognitive performance of young and older adults with contrasting educational backgrounds. We addressed three questions: (1) Is education associated with reduced age-related cognitive decline? (2) Does the presence of SNPs explain the variation in cognitive performance observed late in life? (3) Is education differentially associated with cognition based on the presence of BDNF, NTRK2, or FNDC5 polymorphisms? We measured the cognitive functions of young and older participants, with lower and higher education, using specific and sensitive tests of the Cambridge Automated Neuropsychological Test Assessment Battery. A three-way ANOVA revealed that SNPs were associated with differential performances in executive functions, episodic memory, sustained attention, mental and motor response speed, and visual recognition memory and that higher educational levels improved the affected cognitive functions. The results revealed that distinct SNPs affect cognition late in life differentially, suggesting their utility as potential biomarkers and emphasizing the importance of cognitive stimulation that advanced education early in life provides.

Cornerstone Cellular Pathways for Metabolic Disorders and Diabetes Mellitus: Non-Coding RNAs, Wnt Signaling, and AMPK

Metabolic disorders and diabetes (DM) impact more than five hundred million individuals throughout the world and are insidious in onset, chronic in nature, and yield significant disability and death. Current therapies that address nutritional status, weight management, and pharmacological options may delay disability but cannot alter disease course or functional organ loss, such as dementia and degeneration of systemic bodily functions. Underlying these challenges are the onset of aging disorders associated with increased lifespan, telomere dysfunction, and oxidative stress generation that lead to multi-system dysfunction. These significant hurdles point to the urgent need to address underlying disease mechanisms with innovative applications. New treatment strategies involve non-coding RNA pathways with microRNAs (miRNAs) and circular ribonucleic acids (circRNAs), Wnt signaling, and Wnt1 inducible signaling pathway protein 1 (WISP1) that are dependent upon programmed cell death pathways, cellular metabolic pathways with AMP-activated protein kinase (AMPK) and nicotinamide, and growth factor applications. Non-coding RNAs, Wnt signaling, and AMPK are cornerstone mechanisms for overseeing complex metabolic pathways that offer innovative treatment avenues for metabolic disease and DM but will necessitate continued appreciation of the ability of each of these cellular mechanisms to independently and in unison influence clinical outcome.

The impact of aging and oxidative stress in metabolic and nervous system disorders: programmed cell death and molecular signal transduction crosstalk

Life expectancy is increasing throughout the world and coincides with a rise in non-communicable diseases (NCDs), especially for metabolic disease that includes diabetes mellitus (DM) and neurodegenerative disorders. The debilitating effects of metabolic disorders influence the entire body and significantly affect the nervous system impacting greater than one billion people with disability in the peripheral nervous system as well as with cognitive loss, now the seventh leading cause of death worldwide. Metabolic disorders, such as DM, and neurologic disease remain a significant challenge for the treatment and care of individuals since present therapies may limit symptoms but do not halt overall disease progression. These clinical challenges to address the interplay between metabolic and neurodegenerative disorders warrant innovative strategies that can focus upon the underlying mechanisms of aging-related disorders, oxidative stress, cell senescence, and cell death. Programmed cell death pathways that involve autophagy, apoptosis, ferroptosis, and pyroptosis can play a critical role in metabolic and neurodegenerative disorders and oversee processes that include insulin resistance, β-cell function, mitochondrial integrity, reactive oxygen species release, and inflammatory cell activation. The silent mating type information regulation 2 homolog 1 (Saccharomyces cerevisiae) (SIRT1), AMP activated protein kinase (AMPK), and Wnt1 inducible signaling pathway protein 1 (WISP1) are novel targets that can oversee programmed cell death pathways tied to β-nicotinamide adenine dinucleotide (NAD+), nicotinamide, apolipoprotein E (APOE), severe acute respiratory syndrome (SARS-CoV-2) exposure with coronavirus disease 2019 (COVID-19), and trophic factors, such as erythropoietin (EPO). The pathways of programmed cell death, SIRT1, AMPK, and WISP1 offer exciting prospects for maintaining metabolic homeostasis and nervous system function that can be compromised during aging-related disorders and lead to cognitive impairment, but these pathways have dual roles in determining the ultimate fate of cells and organ systems that warrant thoughtful insight into complex autofeedback mechanisms.

Endothelial Glycocalyx in Aging and Age-related Diseases

The worldwide population is aging exponentially, creating burdens to patients, their families and society. Increasing age is associated with higher risk of a wide range of chronic diseases, and aging of the vascular system is closely linked to the development of many age-related diseases. Endothelial glycocalyx is a layer of proteoglycan polymers on the surface of the inner lumen of blood vessels. It plays an important role in maintaining vascular homeostasis and protecting various organ functions. Endothelial glycocalyx loss happens through the aging process and repairing the endothelial glycocalyx may alleviate the symptoms of age-related diseases. Given the important role of the glycocalyx and its regenerative properties, it is posited that the endothelial glycocalyx may be a potential therapeutic target for aging and age-related diseases and repairing endothelial glycocalyx could play a role in the promotion of healthy aging and longevity. Here, we review the composition, function, shedding, and manifestation of the endothelial glycocalyx in aging and age-related diseases, as well as regeneration of endothelial glycocalyx.

Recombinant Human HAPLN1 Mitigates Pulmonary Emphysema by Increasing TGF-β Receptor I and Sirtuins Levels in Human Alveolar Epithelial Cells

Chronic obstructive pulmonary disease (COPD) will be the third leading cause of death worldwide by 2030. One of its components, emphysema, has been defined as a lung disease that irreversibly damages the lungs' alveoli. Treatment is currently unavailable for emphysema symptoms and complete cure of the disease. Hyaluronan (HA) and proteoglycan link protein 1 (HAPLN1), an HA-binding protein linking HA in the extracellular matrix to stabilize the proteoglycan structure, forms a bulky hydrogel-like aggregate. Studies on the biological role of the full-length HAPLN1, a simple structure-stabilizing protein, are limited. Here, we demonstrated for the first time that treating human alveolar epithelial type 2 cells with recombinant human HAPLN1 (rhHAPLN1) increased TGF-β receptor 1 (TGF-β RI) protein levels, but not TGF-β RII, in a CD44-dependent manner with concurrent enhancement of the phosphorylated Smad3 (p-Smad3), but not p-Smad2, upon TGF-β1 stimulation. Furthermore, rhHAPLN1 significantly increased sirtuins levels (i.e., SIRT1/2/6) without TGF-β1 and inhibited acetylated p300 levels that were increased by TGF-β1. rhHAPLN1 is crucial in regulating cellular senescence, including p53, p21, and p16, and inflammation markers such as p-NF-κB and Nrf2. Both senile emphysema mouse model induced via intraperitoneal rhHAPLN1 injections and porcine pancreatic elastase (PPE)-induced COPD mouse model generated via rhHAPLN1-containing aerosols inhalations showed a significantly potent efficacy in reducing alveolar spaces enlargement. Preclinical trials are underway to investigate the effects of inhaled rhHAPLN1-containing aerosols on several COPD animal models.

Immunomodulatory Effects of SGLT2 Inhibitors-Targeting Inflammation and Oxidative Stress in Aging

Given that the increase in the aging population has grown into one of the largest public health issues, inflammation and oxidative stress, which are closely associated with the aging process, became a focus of recent research. Sodium-glucose co-transporter 2 (SGLT2) inhibitors, a group of drugs initially developed as oral antidiabetics, have shown many beneficial effects over time, including improvement in renal function and cardioprotective effects. It has been shown that SGLT2 inhibitors, as a drug class, have an immunomodulatory and antioxidative effect, affecting endothelial function as well as metabolic parameters. Therefore, it is not surprising that various studies have investigated the potential mechanisms of action of SGLT2 inhibitors in age-related diseases. The proposed mechanisms by which SGLT2 inhibitors can achieve their anti-inflammatory effects include influence on AMPK/SIRT1/PGC-1α signaling, various cytokines, and the NLRP3 inflammasome. The antioxidative effect is related to their action on mitochondria and their influence on the signaling pathways of transforming growth factor β and nuclear erythroid 2-related factor 2/antioxidant response element. Also, SGLT2 inhibitors achieve their anti-inflammatory and antioxidative effects by affecting metabolic parameters, such as uric acid reduction, stimulation of ketogenesis, reduction of body weight, lipolysis, and epicardial fat tissue. Finally, SGLT2 inhibitors display anti-atherosclerotic effects that modulate inflammatory reactions, potentially resulting in improvement in endothelial function. This narrative review offers a complete and comprehensive overview of the possible pathophysiologic mechanisms of the SGLT2 inhibitors involved in the aging process and development of age-related disease. However, in order to use SGLT2 inhibitor drugs as an anti-aging therapy, further basic and clinical research is needed to elucidate the potential effects and complex mechanisms they have on inflammation processes.

Innovative therapeutic strategies for cardiovascular disease

As a significant non-communicable disease, cardiovascular disease is the leading cause of death for both men and women, comprises almost twenty percent of deaths in most racial and ethnic groups, can affect greater than twenty-five million individuals worldwide over the age of twenty, and impacts global economies with far-reaching financial challenges. Multiple factors can affect the onset of cardiovascular disease that include high serum cholesterol levels, elevated blood pressure, tobacco consumption and secondhand smoke exposure, poor nutrition, physical inactivity, obesity, and concurrent diabetes mellitus. Yet, addressing any of these factors cannot completely eliminate the onset or progression of cardiovascular disorders. Novel strategies are necessary to target underlying cardiovascular disease mechanisms. The silent mating type information regulation 2 homolog 1 (Saccharomyces cerevisiae) (SIRT1), a histone deacetylase, can limit cardiovascular injury, assist with stem cell development, oversee metabolic homeostasis through nicotinamide adenine dinucleotide (NAD+) pathways, foster trophic factor protection, and control cell senescence through the modulation of telomere function. Intimately tied to SIRT1 pathways are mammalian forkhead transcription factors (FoxOs) which can modulate cardiac disease to reduce oxidative stress, repair microcirculation disturbances, and reduce atherogenesis through pathways of autophagy, apoptosis, and ferroptosis. AMP activated protein kinase (AMPK) also is critical among these pathways for the oversight of cardiac cellular metabolism, insulin sensitivity, mitochondrial function, inflammation, and the susceptibility to viral infections such as severe acute respiratory syndrome coronavirus that can impact cardiovascular disease. Yet, the relationship among these pathways is both intricate and complex and requires detailed insight to successfully translate these pathways into clinical care for cardiovascular disorders.

Cognitive Impairment in Multiple Sclerosis

Almost three million individuals suffer from multiple sclerosis (MS) throughout the world, a demyelinating disease in the nervous system with increased prevalence over the last five decades, and is now being recognized as one significant etiology of cognitive loss and dementia. Presently, disease modifying therapies can limit the rate of relapse and potentially reduce brain volume loss in patients with MS, but unfortunately cannot prevent disease progression or the onset of cognitive disability. Innovative strategies are therefore required to address areas of inflammation, immune cell activation, and cell survival that involve novel pathways of programmed cell death, mammalian forkhead transcription factors (FoxOs), the mechanistic target of rapamycin (mTOR), AMP activated protein kinase (AMPK), the silent mating type information regulation 2 homolog 1 (Saccharomyces cerevisiae) (SIRT1), and associated pathways with the apolipoprotein E (APOE-ε4) gene and severe acute respiratory syndrome coronavirus (SARS-CoV-2). These pathways are intertwined at multiple levels and can involve metabolic oversight with cellular metabolism dependent upon nicotinamide adenine dinucleotide (NAD+). Insight into the mechanisms of these pathways can provide new avenues of discovery for the therapeutic treatment of dementia and loss in cognition that occurs during MS.

Late Effects of Chronic Low Dose Rate Total Body Irradiation on the Heart Proteome of ApoE-/- Mice Resemble Premature Cardiac Ageing

Recent epidemiologic studies support an association between chronic low-dose radiation exposure and the development of cardiovascular disease (CVD). The molecular mechanisms underlying the adverse effect of chronic low dose exposure are not fully understood. To address this issue, we have investigated changes in the heart proteome of ApoE deficient (ApoE^-/-) C57Bl/6 female mice chronically irradiated for 300 days at a very low dose rate (1 mGy/day) or at a low dose rate (20 mGy/day), resulting in cumulative whole-body doses of 0.3 Gy or 6.0 Gy, respectively. The heart proteomes were compared to those of age-matched sham-irradiated ApoE^-/- mice using label-free quantitative proteomics. Radiation-induced proteome changes were further validated using immunoblotting, enzyme activity assays, immunohistochemistry or targeted transcriptomics. The analyses showed persistent alterations in the cardiac proteome at both dose rates; however, the effect was more pronounced following higher dose rates. The altered proteins were involved in cardiac energy metabolism, ECM remodelling, oxidative stress, and ageing signalling pathways. The changes in PPARα, SIRT, AMPK, and mTOR signalling pathways were found at both dose rates and in a dose-dependent manner, whereas more changes in glycolysis and ECM remodelling were detected at the lower dose rate. These data provide strong evidence for the possible risk of cardiac injury following chronic low dose irradiation and show that several affected pathways following chronic irradiation overlap with those of ageing-associated heart pathology.

Neurotrophic effects of intermittent fasting, calorie restriction and exercise: a review and annotated bibliography

In the last decades, important progress has been achieved in the understanding of the neurotrophic effects of intermittent fasting (IF), calorie restriction (CR) and exercise. Improved neuroprotection, synaptic plasticity and adult neurogenesis (NSPAN) are essential examples of these neurotrophic effects. The importance in this respect of the metabolic switch from glucose to ketone bodies as cellular fuel has been highlighted. More recently, calorie restriction mimetics (CRMs; resveratrol and other polyphenols in particular) have been investigated thoroughly in relation to NSPAN. In the narrative review sections of this manuscript, recent findings on these essential functions are synthesized and the most important molecules involved are presented. The most researched signaling pathways (PI3K, Akt, mTOR, AMPK, GSK3β, ULK, MAPK, PGC-1α, NF-κB, sirtuins, Notch, Sonic hedgehog and Wnt) and processes (e.g., anti-inflammation, autophagy, apoptosis) that support or thwart neuroprotection, synaptic plasticity and neurogenesis are then briefly presented. This provides an accessible entry point to the literature. In the annotated bibliography section of this contribution, brief summaries are provided of about 30 literature reviews relating to the neurotrophic effects of interest in relation to IF, CR, CRMs and exercise. Most of the selected reviews address these essential functions from the perspective of healthier aging (sometimes discussing epigenetic factors) and the reduction of the risk for neurodegenerative diseases (Alzheimer's disease, Huntington's disease, Parkinson's disease) and depression or the improvement of cognitive function.

Ferulic Acid: Signaling Pathways in Aging

The need for clinical remedies to the multiple age-related deficiencies in skin function brought on by extrinsic and intrinsic causes is increased by these demographic changes. Reactive oxygen species (ROS), mitochondrial deoxyribonucleic acid (mtDNA) mutations, telomere shortening, as well as other factors, contribute to the aging of the skin. In this overview, the issue of human skin aging is introduced, along with several pathways and the protective effects of ferulic acid in light of current patents. The complex antioxidant effect of ferulic acid depends on the "sweeping" away of free radicals as well as the suppression of the synthesis of ROS or nitrogen. Furthermore, Cu (II) or Fe protonated metal ions are chelated by this acid (II). Ferulic acid is a free radical scavenger as well as an enzyme inhibitor, increasing the activity of enzymes that scavenge free radicals while decreasing the activity of enzymes that speed up the creation of free radicals. AMPK signalling, which can regulate cellular homeostasis, stress tolerance, cell survival and proliferation, cell death, and autophagy, has recently been linked to aging and lifespan. Therefore, Caenorhabditis elegans (C. elegans) and rodents had longer life-spans due to specific AMPK activation. By inhibiting the TGF-β/Smad signalling pathway, UV irradiation can reduce the production of procollagen. Glycation changes the skin's physical characteristics, making it less elastic and stiffer. . Excessive free radicals simultaneously trigger the nuclear factor kappa B (NF- κB) signalling pathway, increasing TNF levels and matrix metalloproteinase production (MMPs).

Cellular Metabolism: A Fundamental Component of Degeneration in the Nervous System

It is estimated that, at minimum, 500 million individuals suffer from cellular metabolic dysfunction, such as diabetes mellitus (DM), throughout the world. Even more concerning is the knowledge that metabolic disease is intimately tied to neurodegenerative disorders, affecting both the central and peripheral nervous systems as well as leading to dementia, the seventh leading cause of death. New and innovative therapeutic strategies that address cellular metabolism, apoptosis, autophagy, and pyroptosis, the mechanistic target of rapamycin (mTOR), AMP activated protein kinase (AMPK), growth factor signaling with erythropoietin (EPO), and risk factors such as the apolipoprotein E (APOE-ε4) gene and coronavirus disease 2019 (COVID-19) can offer valuable insights for the clinical care and treatment of neurodegenerative disorders impacted by cellular metabolic disease. Critical insight into and modulation of these complex pathways are required since mTOR signaling pathways, such as AMPK activation, can improve memory retention in Alzheimer's disease (AD) and DM, promote healthy aging, facilitate clearance of β-amyloid (Aß) and tau in the brain, and control inflammation, but also may lead to cognitive loss and long-COVID syndrome through mechanisms that can include oxidative stress, mitochondrial dysfunction, cytokine release, and APOE-ε4 if pathways such as autophagy and other mechanisms of programmed cell death are left unchecked.

GPR19 Coordinates Multiple Molecular Aspects of Stress Responses Associated with the Aging Process

G protein-coupled receptors (GPCRs) play a significant role in controlling biological paradigms such as aging and aging-related disease. We have previously identified receptor signaling systems that are specifically associated with controlling molecular pathologies associated with the aging process. Here, we have identified a pseudo-orphan GPCR, G protein-coupled receptor 19 (GPR19), that is sensitive to many molecular aspects of the aging process. Through an in-depth molecular investigation process that involved proteomic, molecular biological, and advanced informatic experimentation, this study found that the functionality of GPR19 is specifically linked to sensory, protective, and remedial signaling systems associated with aging-related pathology. This study suggests that the activity of this receptor may play a role in mitigating the effects of aging-related pathology by promoting protective and remedial signaling systems. GPR19 expression variation demonstrates variability in the molecular activity in this larger process. At low expression levels in HEK293 cells, GPR19 expression regulates signaling paradigms linked with stress responses and metabolic responses to these. At higher expression levels, GPR19 expression co-regulates systems involved in sensing and repairing DNA damage, while at the highest levels of GPR19 expression, a functional link to processes of cellular senescence is seen. In this manner, GPR19 may function as a coordinator of aging-associated metabolic dysfunction, stress response, DNA integrity management, and eventual senescence.

Studying the Geroprotective Properties of YAP/TAZ Signaling Inhibitors on Drosophila melanogaster Model

The transcriptional coactivators Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ) are the main downstream effectors of the evolutionarily conserved Hippo signaling pathway. YAP/TAZ are implicated in the transcriptional regulation of target genes that are involved in a wide range of key biological processes affecting tissue homeostasis and play dual roles in the aging process, depending on the cellular and tissue context. The aim of the present study was to investigate whether pharmacological inhibitors of Yap/Taz increase the lifespan of Drosophila melanogaster. Real-time qRT-PCR was performed to measure the changes in the expression of Yki (Yorkie, the Drosophila homolog of YAP/TAZ) target genes. We have revealed a lifespan-increasing effect of YAP/TAZ inhibitors that was mostly associated with decreased expression levels of the wg and E2f1 genes. However, further analysis is required to understand the link between the YAP/TAZ pathway and aging.

Compound combinations targeting longevity: Challenges and perspectives

Aging is one of the world's greatest concerns, requiring urgent, effective, large-scale interventions to decrease the number of late-life chronic diseases and improve human healthspan. Anti-aging drug therapy is one of the most promising strategies to combat the effects of aging. However, most geroprotective compounds are known to successfully affect only a few aging-related targets. Given this, there is a great biological rationale for the use of combinations of anti-aging interventions. In this review, we characterize the various types of compound combinations used to modulate lifespan, discuss the existing evidence on their role in life extension, and present some key points about current challenges and future prospects for the development of combination drug anti-aging therapy.

Towards future directions in data-integrative supervised prediction of human aging-related genes

Motivation

Identification of human genes involved in the aging process is critical due to the incidence of many diseases with age. A state-of-the-art approach for this purpose infers a weighted dynamic aging-specific subnetwork by mapping gene expression (GE) levels at different ages onto the protein-protein interaction network (PPIN). Then, it analyzes this subnetwork in a supervised manner by training a predictive model to learn how network topologies of known aging- versus non-aging-related genes change across ages. Finally, it uses the trained model to predict novel aging-related gene candidates. However, the best current subnetwork resulting from this approach still yields suboptimal prediction accuracy. This could be because it was inferred using outdated GE and PPIN data. Here, we evaluate whether analyzing a weighted dynamic aging-specific subnetwork inferred from newer GE and PPIN data improves prediction accuracy upon analyzing the best current subnetwork inferred from outdated data.

Results

Unexpectedly, we find that not to be the case. To understand this, we perform aging-related pathway and Gene Ontology term enrichment analyses. We find that the suboptimal prediction accuracy, regardless of which GE or PPIN data is used, may be caused by the current knowledge about which genes are aging-related being incomplete, or by the current methods for inferring or analyzing an aging-specific subnetwork being unable to capture all of the aging-related knowledge. These findings can potentially guide future directions towards improving supervised prediction of aging-related genes via -omics data integration.

Availability and implementation

All data and code are available at zenodo, DOI: 10.5281/zenodo.6995045.

Supplementary information

Supplementary data are available at Bioinformatics Advances online.

Adverse associations of long-term exposure to ambient ozone with molecular biomarkers of aging alleviated by residential greenness in rural Chinese adults

BACKGROUND

Both ambient ozone exposure and residential greenness are linked to the aging process. However, their interactive effect on molecular biomarkers of aging (telomere length (TL) and mitochondrial DNA copy number (mtDNA-CN)) remains unclear.

METHODS

This study was conducted among 6418 rural Chinese adults. The concentration of ambient ozone was assessed using a random forest model. Residential greenness was represented by the normalized difference vegetation index (NDVI). Molecular biomarkers of aging (relative TL and relative mtDNA-CN) were determined by quantitative real-time polymerase chain reaction. Generalized linear regression models were applied to investigate the independent and combined effects of ambient ozone and residential greenness on relative TL and relative mtDNA-CN.

RESULTS

The estimated percent changes and 95 % confidence intervals (CIs) of relative TL in response to per-unit increase in ambient ozone were -22.43 % (-23.74 %, -21.18 %), -14.19 % (-15.63 %, -12.72 %) and -4.50 % (-6.57 %, -2.27 %) for participants with low (NDVI ≤ 0.53), moderate (0.54-0.55) and high (≥0.56) residential greenness exposure, respectively, while the corresponding figures of relative mtDNA-CN were -12.63 % (-13.84 %, -11.31 %), -9.52 % (-10.60 %, -8.33 %) and 2.12 % (0.20 %, 4.19 %). Furthermore, negative interactive effects between ambient ozone and residential greenness exposure on molecular biomarkers of aging were observed (Pfor interaction < 0.001 for relative TL, and 0.098 for relative mtDNA-CN).

CONCLUSIONS

Long-term exposure to high concentrations of ambient ozone and low residential greenness was associated with decreased mtDNA-CN and shortened TL. The adverse effect of ambient ozone exposure on molecular biomarkers of aging may be attenuated by increased residential greenness.

Repurposing SGLT-2 Inhibitors to Target Aging: Available Evidence and Molecular Mechanisms

Caloric restriction promotes longevity in multiple animal models. Compounds modulating nutrient-sensing pathways have been suggested to reproduce part of the beneficial effect of caloric restriction on aging. However, none of the commonly studied caloric restriction mimetics actually produce a decrease in calories. Sodium-glucose cotransporter 2 inhibitors (SGLT2-i) are a class of drugs which lower glucose by promoting its elimination through urine, thus inducing a net loss of calories. This effect promotes a metabolic shift at the systemic level, fostering ketones and fatty acids utilization as glucose-alternative substrates, and is accompanied by a modulation of major nutrient-sensing pathways held to drive aging, e.g., mTOR and the inflammasome, overall resembling major features of caloric restriction. In addition, preliminary experimental data suggest that SGLT-2i might also have intrinsic activities independent of their systemic effects, such as the inhibition of cellular senescence. Consistently, evidence from both preclinical and clinical studies have also suggested a marked ability of SGLT-2i to ameliorate low-grade inflammation in humans, a relevant driver of aging commonly referred to as inflammaging. Considering also the amount of data from clinical trials, observational studies, and meta-analyses suggesting a tangible effect on age-related outcomes, such as cardiovascular diseases, heart failure, kidney disease, and all-cause mortality also in patients without diabetes, here we propose a framework where at least part of the benefit provided by SGLT-2i is mediated by their ability to blunt the drivers of aging. To support this postulate, we synthesize available data relative to the effect of this class on: 1- animal models of healthspan and lifespan; 2- selected molecular pillars of aging in preclinical models; 3- biomarkers of aging and especially inflammaging in humans; and 4- COVID-19-related outcomes. The burden of evidence might prompt the design of studies testing the potential employment of this class as anti-aging drugs.

The Role of Hypoxia-Inducible Factor in the Mechanisms of Aging

Aging is accompanied by a reduction in the oxygen delivery to all organs and tissues and decrease in the oxygen partial pressure in them, resulting in the development of hypoxia. The lack of oxygen activates cell signaling pathway mediated by the hypoxia-inducible transcription factor (HIF), which exists in three isoforms - HIF-1, HIF-2, and HIF-3. HIF regulates expression of several thousand genes and is a potential target for the development of new drugs for the treatment of many diseases, including those associated with age. Human organism and organisms of laboratory animals differ in their tolerance to hypoxia and expression of HIF and HIF-dependent genes, which may contribute to the development of inflammatory, tumor, and cardiovascular diseases. Currently, the data on changes in the HIF expression with age are contradictory, which is mostly due to the fact that such studies are conducted in different age groups, cell types, and model organisms, as well as under different hypoxic conditions and mainly in vitro. Furthermore, the observed discrepancies can be due to the individual tolerance of the studied organisms to hypoxia, which is typically not taken into account. Therefore, the purpose of this review was to analyze the published data on the connection between the mechanisms of aging, basal tolerance to hypoxia, and changes in the level of HIF expression with age. Here, we summarized the data on the age-related changes in the hypoxia tolerance, HIF expression and the role of HIF in aging, which is associated with its involvement in the molecular pathways mediated by insulin and IGF-1 (IIS), sirtuins (SIRTs), and mTOR. HIF-1 interacts with many components of the IIS pathway, in particular with FOXO, the activation of which reduces production of reactive oxygen species (ROS) and increases hypoxia tolerance. Under hypoxic conditions, FOXO is activated via both HIF-dependent and HIF-independent pathways, which contributes to a decrease in the ROS levels. The activity of HIF-1 is regulated by all members of the sirtuin family, except SIRT5, while the mechanisms of SIRT interaction with HIF-2 and HIF-3 are poorly understood. The connection between HIF and mTOR and its inhibitor, AMPK, has been identified, but its exact mechanism has yet to be studied. Understanding the role of HIF and hypoxia in aging and pathogenesis of age-associated diseases is essential for the development of new approaches to the personalized therapy of these diseases, and requires further research.

Analysis of Scientometric Indicators in Publications Associated with Healthy Aging in the World, Period 2011-2020

Today, the world population is aging at a fast rate. This scenario of the accelerated aging of human populations entails increased concern for healthy aging that is associated with a rise in scientific production related to the topic. In this study, the Scopus database from Elsevier was used, with a final search carried out on 5 January 2022, and various bibliometric indicators were obtained from SciVal. The study was fundamentally intended to characterize, determine trends, and understand the evolution and current state of research on the concept of "healthy aging" in the last decade. We found that there has been proportionally greater and more accelerated growth in the subject with respect to the general productivity of the world and that countries with high life expectancies tend to have made more effort to investigate this topic. The "hottest" research areas were found to be related to the cognitive aspect and the biological mechanisms involved in aging.

Pharmacological Approaches to Decelerate Aging: A Promising Path

Biological aging or senescence is a course in which cellular function decreases over a period of time and is a consequence of altered signaling mechanisms that are triggered in stressed cells leading to cell damage. Aging is among the principal risk factors for many chronic illnesses such as cancer, cardiovascular disorders, and neurodegenerative diseases. Taking this into account, targeting fundamental aging mechanisms therapeutically may effectively impact numerous chronic illnesses. Selecting ideal therapeutic options in order to hinder the process of aging and decelerate the progression of age-related diseases is valuable. Along therapeutic options, life style modifications may well render the process of aging. The process of aging is affected by alteration in many cellular and signaling pathways amid which mTOR, SIRT1, and AMPK pathways are the most emphasized. Herein, we have discussed the mechanisms of aging focusing mainly on the mentioned pathways as well as the role of inflammation and autophagy in aging. Moreover, drugs and natural products with antiaging properties are discussed in detail.