Immunosenescence and inflammaging in the aging process: age-related diseases or longevity?

Acquired hemophilia A as a disease of the elderly: A comprehensive review of epidemiology, pathogenesis, and novel therapy

Acquired hemophilia A (AHA) is a rare autoimmune bleeding disorder characterized by the development of neutralizing autoantibodies (inhibitors) against coagulation factor VIII (FVIII). This review provides an in-depth exploration of AHA, covering its epidemiology, pathogenesis, clinical presentation, diagnosis, complications, and treatment strategies, focusing on recent advancements. AHA can manifest in both men and women with no prior bleeding history. The annual incidence is estimated to be approximately 1 case per million individuals in the general population. The incidence increases significantly with age: the incidence among individuals aged 60 years or older is approximately 3 to 4 cases per million individuals per year. Typically, patients present with an acquired bleeding disorder that is characterized by an isolated, prolonged activated partial thromboplastin time stemming from FVIII deficiency. Diagnosis relies on the detection of neutralizing antibodies using the Nijmegen-modified Bethesda assay. Hemostatic control strategies involve bypassing agents like recombinant activated factor VII, activated prothrombin complex concentrate, and recombinant porcine FVIII for bleeding patients. Emicizumab, a novel bypassing agent, exhibits several potential advantages. In the realm of immunosuppressive treatment for inhibitor eradication, the CyDRi regimen emerged as a remarkable advancement, significantly enhancing the outlook for the management of AHA even in the elderly frail population.

The interplay of NAD and hypoxic stress and its relevance for ageing

Nicotinamide adenine dinucleotide (NAD) is an essential regulator of cellular metabolism and redox processes. NAD levels and the dynamics of NAD metabolism change with increasing age but can be modulated via the diet or medication. Because NAD metabolism is complex and its regulation still insufficiently understood, achieving specific outcomes without perturbing delicate balances through targeted pharmacological interventions remains challenging. NAD metabolism is also highly sensitive to environmental conditions and can be influenced behaviorally, e.g., by exercise. Changes in oxygen availability directly and indirectly affect NAD levels and may result from exposure to ambient hypoxia, increased oxygen demand during exercise, ageing or disease. Cellular responses to hypoxic stress involve rapid alterations in NAD metabolism and depend on many factors, including age, glucose status, the dose of the hypoxic stress and occurrence of reoxygenation phases, and exhibit complex time-courses. Here we summarize the known determinants of NAD-regulation by hypoxia and evaluate the role of NAD in hypoxic stress. We define the specific NAD responses to hypoxia and identify a great potential of the modulation of NAD metabolism regarding hypoxic injuries. In conclusion, NAD metabolism and cellular hypoxia responses are strongly intertwined and together mediate protective processes against hypoxic insults. Their interactions likely contribute to age-related changes and vulnerabilities. Targeting NAD homeostasis presents a promising avenue to prevent/treat hypoxic insults and - conversely - controlled hypoxia is a potential tool to regulate NAD homeostasis.

The senotherapeutic potential of phytochemicals for age-related intestinal disease

During the last few decades, life expectancy has increased worldwide along with the prevalence of several age-related diseases. Among aging pathways, cellular senescence and chronic inflammation (or "inflammaging") appear to be connected to gut homeostasis and dysbiosis of the microbiome. Cellular senescence is a state of essentially irreversible cell cycle arrest that occurs in response to stress. Although senescent cells (SC) remain metabolically active, they do not proliferate and can secrete inflammatory and other factors comprising the senescence-associated secretory phenotype (SASP). Accumulation of SCs has been linked to onset of several age-related diseases, in the brain, bones, the gastrointestinal tract, and other organs and tissues. The gut microbiome undergoes substantial changes with aging and is tightly interconnected with either successful (healthy) aging or disease. Senotherapeutic drugs are compounds that can clear senescent cells or modulate the release of SASP factors and hence attenuate the impact of the senescence-associated pro-inflammatory state. Phytochemicals, phenolic compounds and terpenes, which have antioxidant and anti-inflammatory activities, could also be senotherapeutic given their ability to act upon senescence-linked cellular pathways. The aim of this review is to dissect links among the gut microbiome, cellular senescence, inflammaging, and disease, as well as to explore phytochemicals as potential senotherapeutics, focusing on their interactions with gut microbiota. Coordinated targeting of these inter-related processes might unveil new strategies for promoting healthy aging.

Immunosenescence and age-related immune cells: causes of age-related diseases

Immunosenescence is a weakening of the immune system due to aging, characterized by changes in immune cells and dysregulated immune function. Age-related immune cells are increasing with aging. They are associated with chronic prolonged inflammation, causing tissue dysfunction and age-related diseases. Here, we discuss increased pro-inflammatory activity of aged macrophages, accumulation of lymphocytes with an age-associated phenotype, and specific alterations in both functions and characteristics of these immune cells. These cellular changes are associated with development of age-related diseases. Additionally, we reviewed various therapeutic strategies targeting age-related immunosenescence, providing pathways to mitigate effects of age-related diseases.

Centenarians-the way to healthy vascular ageing and longevity: a review from VascAgeNet

The prevalence of centenarians, people who lived 100 years and longer, is steadily growing in the last decades. This exceptional longevity is based on multifaceted processes influenced by a combination of intrinsic and extrinsic factors such as sex, (epi-)genetic factors, gut microbiota, cellular metabolism, exposure to oxidative stress, immune status, cardiovascular risk factors, environmental factors, and lifestyle behavior. Epidemiologically, the incidence rate of cardiovascular diseases is reduced in healthy centenarians along with late onset of age-related diseases compared with the general aged population. Understanding the mechanisms that affect vascular ageing in centenarians and the underlying factors could offer valuable insights for developing strategies to improve overall healthy life span in the elderly. This review discusses these key factors influencing vascular ageing and how their modulation could foster healthy longevity.

Single-cell analysis of human peripheral blood reveals high immune response activity in successful ageing individuals

Beneficial remodeling of the immune system in successful ageing individuals (centenarians and supercentenarians) is critical for healthy ageing. However, mechanisms for dynamic regulation of immunity during ageing remain unclear. We use single-cell RNA sequencing (scRNA-seq) as an analytical strategy to study the dynamic regulation of immunity during aging and its molecular mechanisms at the single-cell level. We performed an integrative analysis of 87,215 peripheral blood mononuclear cells, from seven supercentenarians, three centenarians, and four elderly controls, generated by single-cell transcriptomics complemented with fluorescence-activated cell sorting. Animals experiments were also conducted to validate the makers of healthy aging found by our bioinformatic analysis and further explore the dynamic of immune changes during aging process. We found that CD8+ effector memory T cells and terminally differentiated B cells were enriched in the longevity group (centenarians and supercentenarians), whereas naïve T cells and Tregs were enriched in elderly controls. CD56dim NK cells in the longevity group activated Fc-γ receptor signaling. The higher antigen-presenting ability of CD14+ monocytes in the longevity group and the CellChat analysis indicated that CD14+ monocytes might assist active T and B cells. Here, we revealed the adaptive immune remodeling geromarkers of immunosenescence in centenarians and supercentenarians, which could be considered as biomarkers of healthy aging, and might help sustain immune responses and achieve exceptional longevity.

Joint association of systemic immune-inflammation index and phenotypic age acceleration with chronic respiratory disease: a cross-sectional study

BACKGROUND

Chronic respiratory diseases (CRD) represents a series of lung disorders and is posing a global health burden. Systemic inflammation and phenotypic ageing have been respectively reported to associate with certain CRD. However, little is known about the co-exposures and mutual associations of inflammation and ageing with CRD. Here, we aim to systematically elucidate the joint and mutual mediating associations of systemic immune-inflammation index (SII) and phenotypic age acceleration (PhenoAgeAccel) with CRD based on data from National Health and Nutrition Examination Survey (NHANES).

METHODS

Data for this study was obtained from NHANES 2007-2010 and 2015-2018. The single and combined associations of SII and PhenoAgeAccel with CRD were analyzed using multivariable logistic regression models. The dose-response relationship between exposures and outcomes was determined by restricted cubic splines (RCS) regression. Subgroup and mediation analyses were further conducted.

RESULTS

Totally, 15,075 participants were enrolled in this study including 3,587 CRD patients. Compare with controls, CRD patients tended to be older, females and present higher SII and PhenoAgeAccel values. Single-index analysis indicated that either SII or PhenoAgeAccel demonstrated a significantly positive association with CRD via logistic regressions and RCS curves. Furthermore, the joint-indexes analysis revealed that compared to individuals with lower SII and PhenoAgeAccel, those with higher SII and PhenoAgeAccel exhibited remarkably stronger associations with CRD (adjusted OR [aOR], 1.56; 95% CI, 1.31-1.85; P < 0.001), chronic obstructive pulmonary disease (aOR, 1.56; 95% CI, 1.22-2.00; P = 0.001) and asthma (aOR, 1.40; 95% CI, 1.16-1.70; P = 0.001), which were predominant among those aged above 40 years, females and smokers. Eventually, mediation analyses suggested the mutual mediating effects of SII and PhenoAgeAccel on CRD and PhenoAgeAccel mediated SII resulting in CRD more significantly.

CONCLUSION

This study confirmed the coexposure effect and mutual mediation between SII and PhenoAgeAccel on CRD. We recommend that the joint assessment may conduce to the accurate identification for populations susceptible to CRD and early prevention of chronic respiratory diseases.

The Role and Implications of Epidermal Dysfunction in the Pathogenesis of Inflammaging

Inflammaging has long been linked to the pathogenesis of various aging-associated disorders, including cardiovascular disease, obesity, type 2 diabetes, and dementia. Yet, the origins of inflammaging remain unclear. Although inflammatory dermatoses such as psoriasis and atopic dermatitis predispose to the development of certain aging-associated disorders, suggesting a pathogenic role of cutaneous inflammation in these disorders, the great majority of aged humans do not have inflammatory dermatoses. Nonetheless, recent studies point to epidermal dysfunction as contributing to inflammaging, even in otherwise normal aged humans. Chronologically aged skin exhibits reduced stratum corneum hydration levels, delayed permeability barrier recovery, and an elevated stratum corneum pH, all of which can provoke and exacerbate cutaneous inflammation. Owing to the prolonged release of proinflammatory cytokines (including TNFα, IL-1β, and IL-6) from the epidermis into the circulation in response to these functional abnormalities, cutaneous inflammation can lead to extracutaneous inflammation, resulting in the downstream development of inflammaging and its accompanying disorders. In support of this concept, topical therapies that improve epidermal function can mitigate some aging-associated disorders, such as mild cognitive impairment. In this perspective, we discuss the link between epidermal dysfunction and inflammaging and highlight the potential management of inflammaging-associated sequelae by enhancing epidermal functions.

Polyphenol Treatment of Peripheral Blood Mononuclear Cells from Individuals of Different Ages

Human peripheral blood mononuclear cells (PBMCs) have been largely utilized to assess the cytotoxic, immunomodulatory, and anti-inflammatory properties of both synthetic and natural compounds. Within the latter category, polyphenols from dietary sources have been extensively analyzed. PBMCs represent a feasible in vitro model to study polyphenol hallmarks and activity according to quantitative and qualitative differences in immune responses in individuals of different age. In this chapter, we propose a method for PBMC treatment with polyphenols and analysis designed on age-dependent qualitative and quantitative variability in immune cell performance.

Cartilage Endplate-Targeted Engineered Exosome Releasing and Acid Neutralizing Hydrogel Reverses Intervertebral Disc Degeneration

Cartilage endplate cell (CEPC) and nucleus pulposus cell (NPC) inflammation are critical factors that contribute to intervertebral disc degeneration (IVDD). Recent evidence indicated that iron ion influx, reactive oxygen species (ROS), and the cGAS-STING pathway are involved in CEPC inflammatory degeneration. Moreover, cytokines produced by degenerating CEPCs and lactic acid accumulation within the microenvironment significantly contribute to NPC inflammation. Consequently, simultaneous alleviation of CEPC inflammation and correction of the acidic microenvironment are anticipated to reverse IVDD. Herein, CEPC-targeted engineered exosomes loaded with salvianolic acid A are incorporated into a CaCO3/chitosan hydrogel, forming a composite gel, CAP-sEXOs@Gel. Notably, CAP-sEXOs@Gel shows long local retention, realizes the slow release of CAP-sEXOs and specific uptake by CEPCs. After uptake by CEPCs, CAP-sEXOs reduce intracellular iron ion and ROS by inhibiting hypoxia-inducible factor-2α (HIF-2α)/TfR1 expression. Iron ion influx and ROS inhibition contribute to the maintenance of normal mitochondrial function and reduced mtDNA leakage, suppresing the cGAS-STING pathway. Additionally, the CaCO3 component of CAP-sEXOs@Gel neutralizes H+, thereby alleviating NPC inflammation. Collectively, this novel composite hydrogel demonstrates the ability to concurrently inhibit CEPC and NPC inflammation, thereby presenting a promising therapeutic approach for IVDD.

Fecal microbiota transplantation, a tool to transfer healthy longevity

The complex gut microbiome influences host aging and plays an important role in the manifestation of age-related diseases. Restoring a healthy gut microbiome via Fecal Microbiota Transplantation (FMT) is receiving extensive consideration to therapeutically transfer healthy longevity. Herein, we comprehensively review the benefits of gut microbial rejuvenation - via FMT - to promote healthy aging, with few studies documenting life length properties. This review explores how preconditioning donors via standard - lifestyle and pharmacological - antiaging interventions reshape gut microbiome, with the resulting benefits being also FMT-transferable. Finally, we expose the current clinical uses of FMT in the context of aging therapy and address FMT challenges - regulatory landscape, protocol standardization, and health risks - that require refinement to effectively utilize microbiome interventions in the elderly.

2'-Fucosyllactose attenuates aging-related metabolic disorders through modulating gut microbiome-T cell axis

Aging-related metabolic disorders seriously affect the lifespan of middle-aged and older people, potentially due to disruptions in the adaptive immune and gut microbial profiles. Dietary intervention offers a promising strategy for maintaining metabolic health. This study aimed to investigate the ameliorative effect of 2'-fucosyllactose (2'-FL) on aging-induced metabolic dysfunction and the underlying mechanisms. The results revealed that 2'-FL significantly relieved aging-related metabolic disorders, including weight gain, lipid deposition, dyslipidemia, glucose intolerance, systemic inflammation, and abnormal hepatic metabolism. Flow cytometry analysis revealed a significant reduction in T cytotoxic (Tc), T helper (Th), and regulatory T (Treg) cells and a significant increase in Th17 cells in aged mice, while 2'-FL relieved the aging-induced proportional changes in Th and Th17 subtypes. The aging intestinal microecology was characterized by higher Th17/Treg ratios, impaired gut barrier function, lower gut bacterial diversity, decreased abundance of beneficial genera including Ligilactobacillus, Colidextribacter, Mucispirillum, and Lachnoclostridium, and increased abundance of harmful bacteria including Turicibacter and Desulfovibrio, which was ameliorated by 2'-FL treatment. These findings highlight that 2'-FL is an ideal dietary prebiotic for improving aging-related metabolic disorders by modulating both the adaptive immune system and the gut microbial profile.

Influenza and Aging: Clinical Manifestations, Complications, and Treatment Approaches in Older Adults

Influenza, a highly contagious respiratory viral illness, poses significant global health risks, particularly affecting older and those with chronic health conditions. Influenza viruses, primarily types A and B, are responsible for seasonal human infections and exhibit a propensity for antigenic drift and shift, contributing to seasonal epidemics and pandemics. The severity of influenza varies, but severe cases often lead to pneumonia, acute respiratory distress syndrome, and multiorgan failure. Older adults, especially those over 65 years of age, face increased risks of immune senescence, chronic comorbidities, and decreased vaccine efficacy. Globally, influenza affects millions of people annually, with significant morbidity and mortality among older. Epidemiological patterns vary with climate, and risk factors include age, immunocompromised status, and preexisting chronic conditions. In older adults, influenza frequently results in hospitalization and death, which is exacerbated by immunosenescence and biological organ changes associated with aging. Clinical manifestations range from mild symptoms to severe complications such as viral pneumonia and multiorgan failure. Diagnosis often relies on antigen or molecular tests, with radiological examination aiding in severe cases. Treatment primarily involves antiviral agents, such as oseltamivir and peramivir, with the greatest benefit observed when initiated early. Management of severe cases may require hospitalization and supportive care, including addressing complications, such as secondary bacterial infections and cardiovascular events. This article highlights the need for improved vaccination strategies and novel treatments, including monoclonal antibodies and adoptive T cell therapies, to better manage severe influenza infections in vulnerable populations such as older.

In-depth human immune cellular profiling from newborn to frail

Immune functional decline and remodeling accompany aging and frailty. It is still largely unknown how changes in the immune cellular composition differentiate healthy individuals from those who become frail at a relatively early age. Our aim in this exploratory study was to investigate immunological changes from newborn to frailty and the association between health statute and various immune cell subtypes. The participants analyzed in this study covered human cord blood cells and peripheral blood cells collected from young adults and healthy and frail old individuals. A total of 30 immune cell subsets were performed by flow cytometry based on the surface markers of immune cells. Furthermore, frailty was investigated for its relations with various leukocyte subpopulations. Frail individuals exhibited a higher CD4/CD8 ratio; a higher proportion of CD4+ central memory T cells, CD8+ effector memory T cells, CD27- switched memory B (BSM) cells, CD27+ BSM cells, age-associated B cells, and CD38-CD24- B cells; and a lower proportion of naïve CD8+ T cells and progenitor B cells. The frailty index score was found to be associated with naïve T cells, CD4/CD8 ratio, age-associated B cells, CD27- BSM cells, and CD4+ central memory T cells. Our findings conducted a relatively comprehensive and extensive atlas of age- and frailty-related changes in peripheral leukocyte subpopulations from newborn to frailty. The immune phenotypes identified in this study can contribute to a deeper understanding of immunosenescence in frailty and may provide a rationale for future interventions and diagnosis.

Understanding the impact of ER stress on lung physiology

Human lungs consist of a distinctive array of cell types, which are subjected to persistent challenges from chemical, mechanical, biological, immunological, and xenobiotic stress throughout life. The disruption of endoplasmic reticulum (ER) homeostatic function, triggered by various factors, can induce ER stress. To overcome the elevated ER stress, an adaptive mechanism known as the unfolded protein response (UPR) is activated in cells. However, persistent ER stress and maladaptive UPR can lead to defects in proteostasis at the cellular level and are typical features of the lung aging. The aging lung and associated lung diseases exhibit signs of ER stress-related disruption in cellular homeostasis. Dysfunction resulting from ER stress and maladaptive UPR can compromise various cellular and molecular processes associated with aging. Hence, comprehending the mechanisms of ER stress and UPR components implicated in aging and associated lung diseases could enable to develop appropriate therapeutic strategies for the vulnerable population.

Natural Modulators of Key Signaling Pathways in Skin Inflammageing

Low-grade chronic inflammation without obvious infection is defined as "inflammageing" and a key driver of skin ageing. Although the importance of modulating inflammageing for treating skin diseases and restoring cutaneous homeostasis is increasingly being recognized. However, the mechanisms underlying skin inflammageing, particularly those associated with natural treatments, have not been systematically elucidated. This review explores the signaling pathways associated with skin inflammageing, as well as the natural plants and compounds that directly or indirectly target these pathways. Nine signaling pathways and 60 plants/constituents related to skin anti-inflammageing are discussed, exploring plant mechanisms to mitigate skin inflammageing. Common natural plants with anti-inflammageing activity are detailed by active ingredients, mechanisms, therapeutic potential, and quantitative effects on skin inflammageing modulation. This review strengthens our understanding of these botanical ingredients as natural interventions against skin inflammageing and provides directions for future research.

Identification and construction of prognostic clusters and risk-prognosis model based on aging-immune related genes in bladder cancer

BACKGROUND

Faced with the current global ageing situation, advanced age has become a risk factor for bladder carcinogenesis progression and immunotherapy. Exploring the common mechanisms of aging and immune in bladder cancer and finding new prognostic markers and immunotherapeutic targets has become an urgent issue.

METHOD

Aging-immune related genes (AIGs) were collected from the public databases MSIGDB, HAGR and ImmPort, and hub AIGs were finally identified in the TCGA-BLCA disease cohort by expression, prognosis, and clinicopathological correlation analysis, and the correlation of hub AIGs with immune microenvironment, immunotherapeutic response, ferroptosis and m6A methylation was verified. Subsequently, prognostic clusters and risk-prognosis models for AIGs was constructed by cluster analysis and multifactorial Cox regression analysis, and the gene mutation and immune infiltration characteristics of the different clusters were explored. Finally, the expression level of related genes was verified by immunohistochemical experiments using patient samples from our medical center.

RESULT

145 potential prognostic AIGs were collected in bladder cancer and finally clarified NFKB1 and IL7 with significant expression differences, prognostic value and age correlation. By single gene analysis, hub AIGs were explored to be significantly correlated with immunotherapeutic response, immune microenvironment, ferroptosis and m6A methylation. Subsequently, the risk-prognosis model was constructed with Riskscore = (0.0581)*NFKB1 + (- 0.2285)*IL7. And prognostic clusters based on hub AIGs was performed by cluster analysis, which clarified that the high-risk group was the pro-cancer group, which had a lower mutation rate of hub genes and higher of neutrophil infiltration. Finally, immunohistochemistry of patients confirmed that IL7 and NFKB1 were underexpressed in bladder cancer, and the proliferation and migration ability of tumor cells were significantly decreased after overexpression of these genes.

CONCLUSION

This study is the first to identify NFKB1 and IL7 as hub AIGs in bladder cancer, which provide new prognostic markers and immunotherapeutic targets.

Herpesvirus Antibodies Are Correlated With Greater Expression of p16 in the T Cells of Humans

Background

There is an increasing awareness that aging of the immune system, or immunosenescence, is a key biological process underlying many of the hallmark diseases of aging and age-related decline broadly. While immunosenescence can be in part due to normal age-related changes in the immune system, emerging evidence posits that viral infections may be biological stressors of the immune system that accelerate the pace of immunosenescence.

Methods

We used a convenience sample of 42 individuals aged 65 years and older to examine correlations between antiviral immunoglobulin G (IgG) levels for 4 human herpesviruses (cytomegalovirus [CMV], herpes simplex virus [types 1 and 2], and Epstein-Barr virus) and multiple indicators of T-cell immunosenescence.

Results

We found that most of the sample (n = 33) was antiviral IgG positive for 2 or more of the 4 herpesvirus infections. We also examined correlations between both the total number of viruses for which an individual had antiviral IgG and each individual virus and multiple indicators of T-cell immunosenescence, particularly p16 expression. The strongest correlations were observed between the total number of viruses for which an individual had detectable antiviral IgG and p16 mean fluorescent intensity (MFI) among CD27-CD28-CD57+ CD4+ cells (r = 0.60; P < .001) and between anti-CMV IgG and p16 MFI of CD27-CD57+ CD4+ cells (r = 0.59; P < .001).

Conclusions

Broadly, our findings offer compelling preliminary evidence for future investigations to incorporate multiple indicators of persistent viral infections and a more comprehensive set of markers of T-cell immunosenescence in population-based studies of aging.

PM2.5-mediated cardiovascular disease in aging: Cardiometabolic risks, molecular mechanisms and potential interventions

Air pollution, particularly fine particulate matter (PM2.5) with <2.5 μm in diameter, is a major public health concern. Studies have consistently linked PM2.5 exposure to a heightened risk of cardiovascular diseases (CVDs) such as ischemic heart disease (IHD), heart failure (HF), and cardiac arrhythmias. Notably, individuals with pre-existing age-related cardiometabolic conditions appear more susceptible. However, the specific impact of PM2.5 on CVDs susceptibility in older adults remains unclear. Therefore, this review addresses this gap by discussing the factors that make the elderly more vulnerable to PM2.5-induced CVDs. Accordingly, we focused on physiological aging, increased susceptibility, cardiometabolic risk factors, CVDs, and biological mechanisms. This review concludes by examining potential interventions to reduce exposure and the adverse health effects of PM2.5 in the elderly population. The latter includes dietary modifications, medications, and exploration of the potential benefits of supplements. By comprehensively analyzing these factors, this review aims to provide a deeper understanding of the detrimental effects of PM2.5 on cardiovascular health in older adults. This knowledge can inform future research and guide strategies to protect vulnerable populations from the adverse effects of air pollution.

Association of exposure to air pollutants and risk of mortality among people living with HIV: a systematic review

BACKGROUND

People living with HIV (PLWH) are more vulnerable to infectious and non-infectious comorbidities due to chronic inflammation and immune dysfunction. Air pollution is a major global health risk, contributing to millions of deaths annually, primarily from cardiovascular and respiratory diseases. However, the link between air pollution and mortality risk in PLWH is underexplored. This systematic review assesses the association between exposure to pollutants such as particulate matter (PM), nitrogen dioxide (NO2), sulfur dioxide (SO2), ozone (O3), and carbon monoxide (CO) and mortality risk in PLWH.

METHODS

A systematic search of PubMed, Web of Science, and Embase was conducted for studies published up to August 2024. Eligibility criteria included cohort, case-control, and cross-sectional studies assessing air pollution exposure and mortality in PLWH. Nested-Knowledge software was used for screening and data extraction. The Newcastle-Ottawa Scale was applied for quality assessment. A narrative approach and tabular summarization were used for data synthesis and presentation.

RESULTS

Nine studies, mostly from China, demonstrated a significant association between long-term exposure to PM1, PM2.5, and PM10 and increased risks of AIDS-related and all-cause mortality in PLWH. Hazard ratios for mortality increased by 2.38-5.13% per unit increase in PM concentrations, with older adults (> 60), females, and those with lower CD4 counts (< 500 cells/µL) being more vulnerable. Short-term exposure to ozone and sulfur dioxide also increased mortality risks, particularly during the warm season and in older populations. Specific pollutants like ammonium (NH4⁺) and sulfate (SO4²⁻) had the strongest links to elevated mortality.

CONCLUSION

Air pollution, especially fine particulate matter and ozone, is associated with a higher risk of mortality in PLWH. Targeted interventions to reduce pollution exposure in vulnerable subgroups are crucial. Further research is needed to confirm these findings in diverse regions and develop effective mitigation strategies.

Aging, ROS, and cellular senescence: a trilogy in the progression of liver fibrosis

Ageing is an inevitable and multifaceted biological process that impacts a wide range of cellular and molecular mechanisms, leading to the development of various diseases, such as liver fibrosis. Liver fibrosis progresses to cirrhosis, which is an advanced form due to high amounts of extracellular matrix and restoration of normal liver structure with failure to repair damaged tissue and cells, marking the end of liver function and total liver failure, ultimately death. The most important factors are reactive oxygen species (ROS) and cellular senescence. Oxidative stress is defined as an impairment by ROS, which are by-products of the mitochondrial electron transport chain and other key molecular pathways that induce cell damage and can activate cellular senescence pathways. Cellular senescence is characterized by pro-inflammatory cytokines, growth factors, and proteases secreted by senescent cells, collectively known as the senescence-associated secretory phenotype (SASP). The presence of senescent cells, which disrupt tissue architecture and function and increase senescent cell production in liver tissues, contributes to fibrogenesis. Hepatic stellate cells (HSCs) are activated in response to chronic liver injury, oxidative stress, and senescence signals that drive excessive production and deposition of extracellular matrix. This review article aims to provide a comprehensive overview of the pathogenic role of ROS and cellular senescence in the aging liver and their contribution to fibrosis.

Effects of COVID-19 on bone fragility: a new perspective from osteoimmunological biomarkers

Introduction

While there is an increasing understanding of COVID-19's effect on different organs, little is known about the effect of the disease on bone turnover and remodeling so far. Osteoimmunological biomarkers have been described as potential indicators of bone remodeling in inflammatory conditions, but their potential role in evaluating the effect of COVID-19 on bone fragility has not been explored so far.

Methods

The present study aims to measure the osteoimmunological biomarkers in elderly patients undergoing orthopedic surgery, to evaluate the potential effect of COVID-19 on the bone response to the surgery.

Results

In our patients, the RANKL/OPG ratio indicated an increase of bone resorption in COVID-19-positive patients, confirming a strong diagnostic and prognostic value. RANKL/OPG displays a good correlation with the bone fragility maker FGF23, indicating that this parameter is a reliable maker of bone fragility in COVID-19 patients and could provide useful and comprehensive information about inflammation-induced bone loss. Consistently, the RANKL/OPG ratio showed a good correlation also with the two inflammatory markers IL-6 and sRAGE.

Discussion

Taken together these results indicate that the use of an osteoimmunological biomarker like the RANKL/OPG ratio could provide a significant improvement in the clinical evaluation of the COVID-19 effect on bone loss. This aspect is extremely important in elderly patients undergoing orthopedic surgery, which can manifest more severe effects of COVID-19 and present an increased level of age-induced bone fragility.

A link between systemic low-grade inflammation and frailty in older adults: clinical evidence from a nationwide population-based study

BACKGROUND/AIMS

Despite the possible role of systemic low-grade inflammation on frailty, the majority of previous studies have focused solely on the phenotypic frailty with limited participant numbers, thereby weakening the evidence supporting the notion that circulating C-reactive protein (CRP) could be a potential frailty biomarker.

METHODS

This study is a nationally representative, population-based, cross-sectional analysis from the Korea National Health and Nutrition Examination Survey, involving 5,359 participants aged 65 and older. We generated a deficit accumulation frailty index (FI) based on 38 items, encompassing physical, cognitive, psychological, and social status. Frailty was classified as non-frail (FI ≤ 0.15), pre-frail (0.15 < FI ≤ 0.25), or frail (FI > 0.25). Serum high-sensitivity CRP (hsCRP) levels were measured by immunoturbidometric method.

RESULTS

After adjusting for confounders including age, sex, income, education, smoking, hypertension, diabetes, dyslipidemia, stroke, cardiovascular diseases, and body mass index, serum hsCRP levels were 29.4% higher in frail participants compared to their non-frail counterparts (p = 0.001). Additionally, circulating hsCRP concentrations positively correlated with the FI (p = 0.003), and the odds ratio for frailty per standard deviation increase in serum hsCRP was 1.18 (p = 0.001). Moreover, older adults in the highest hsCRP quartile exhibited a significant higher FI with a 1.59-fold increased odds ratio for frailty than those in the lowest quartile (p = 0.002 and 0.001, respectively).

CONCLUSION

These findings validate the impact of age-related systemic low-grade inflammation on frailty and support the utility of serum hsCRP as a potential biomarker for detecting frailty in older adults.

Immunosenescence and inflammaging: Mechanisms and role in diseases

Age-related changes initiate a cascade of cellular and molecular alterations that lead to immune system dysfunction or abnormal activation, predisposing individuals to age-related diseases. This phenomenon, commonly referred to as immunosenescence, highlighting aging-associated progressive decline of the immune system. Moreover, mounting evidence suggests that immunosenescence contributes to a related pathological phenomenon known as inflammaging. Inflammaging refers to chronic, low-grade, and systemic inflammation associated with aging, occurring despite the absence of overt stimuli. In the body, inflammation is typically activated in response to overt stimuli such as bacterial/microbial invasion or a pathological state, however, inflammaging occurrence and its underpinning mechanisms seem to be independent and in the absence of such stimuli. Despite recent advancements in molecular characterization and the scrutiny of disease relevance, these two interconnected concepts have remained largely unexplored and unrecognized. In this comprehensive review, we aim to shed light on the mechanistic and cellular aspects of immunosenescence and inflammaging, as well as their pivotal roles in the pathogenesis of aging-related diseases, including cancer, infections, dementia, and neurodegenerative disorders.

Potential mechanism of CARD16 protein action and susceptibility to sepsis in the elderly infected population: Through transcriptome analysis of blood

As global aging accelerates, the super-elderly population is at higher risk of infectious diseases, especially sepsis, a condition that may be associated with declining immune system function and abnormal inflammatory responses. The aim of this study was to investigate the role of CARD16 protein in sepsis susceptibility in the elderly population and its potential mechanism, and to reveal the expression characteristics of CARD16-related genes through blood transcriptomic analysis. Transcriptome sequencing was conducted on peripheral blood samples obtained from patients suffering from senile sepsis, along with samples from a healthy elderly control group. To examine the differences in gene expression, bioinformatics techniques were employed to compare the expression levels of CARD16-related genes between the two groups. Additionally, a comprehensive analysis was performed on the downstream inflammatory pathways and cytokines that are regulated by CARD16.The findings from the transcriptome analysis indicated that the expression of CARD16 was markedly upregulated in the cohort of patients experiencing hypersenile sepsis. This upregulation was associated with an increase in a variety of pro-inflammatory factors. Further network analysis suggested that CARD16 may potentiate the inflammatory response by modulating the NF-κB signaling pathway, which could consequently heighten the patients' vulnerability to sepsis.In comparison to the healthy elderly control group, the levels of anti-inflammatory genes in the super-elderly cohort were found to be significantly diminished. This observation points to a notable imbalance in immune regulation, further emphasizing the altered immune response in individuals with senile sepsis.

RGS10 Attenuates Systemic Immune Dysregulation Induced by Chronic Inflammatory Stress

Regulator of G-protein signaling 10 (RGS10), a key homeostatic regulator of immune cells, has been implicated in multiple diseases associated with aging and chronic inflammation including Parkinson's Disease (PD). Interestingly, subjects with idiopathic PD display reduced levels of RGS10 in subsets of peripheral immune cells. Additionally, individuals with PD have been shown to have increased activated peripheral immune cells in cerebral spinal fluid (CSF) compared to age-matched healthy controls. However, it is unknown whether CSF-resident peripheral immune cells in individuals with PD also exhibit decreased levels of RGS10. Therefore, we performed an analysis of RGS10 levels in the proteomic database of the CSF from the Michael J. Fox Foundation Parkinson's Progression Markers Initiative (PPMI) study. We found that RGS10 levels are decreased in the CSF of individuals with PD compared to healthy controls and prodromal individuals. Moreover, we find that RGS10 levels decrease with age but not PD progression and that males have less RGS10 than females in PD. Importantly, studies have established an association between chronic systemic inflammation (CSI) and neurodegenerative diseases, such as PD, and known sources of CSI have been identified as risk factors for developing PD; however, the role of peripheral immune cell dysregulation in this process has been underexplored. As RGS10 levels are decreased in the CSF and circulating peripheral immune cells of individuals with PD, we hypothesized that RGS10 regulates peripheral immune cell responses to CSI prior to the onset of neurodegeneration. To test this, we induced CSI for 6 weeks in C57BL6/J mice and RGS10 KO mice to assess circulating and CNS-associated peripheral immune cell responses. We found that RGS10 deficiency synergizes with CSI to induce a bias for inflammatory and cytotoxic cell populations, a reduction in antigen presentation in peripheral blood immune cells, as well as in and around the brain that is most notable in males. These results highlight RGS10 as an important regulator of the systemic immune response to CSI and implicate RGS10 as a potential contributor to the development of immune dysregulation in PD.

Age-dependent immune profile in healthy individuals: an original study, systematic review and meta-analysis

BACKGROUND

The circulatory peripheral immune system is the most convenient approach for determining an individual's immune status. Due to various reasons, while previous studies have addressed the critical impact of age, most individual studies did not analyze immunosenescence in a systemic manner, which complicates the possibility of building a reference range for age-dependent immune profiles for effective immune monitoring. To address this gap, this study analyzed a group of healthy individuals to establish age-specific reference ranges of the healthy circulatory immune profile, and a systematic review and meta-analysis were conducted to validate the findings and create generalizable immune cell reference ranges.

RESULTS

Our study recruited a total of 363 healthy Taiwanese adults (median age 42 years [IQR 30, 62], age range 21 to 87 years, 43.3% male), including 158 under 40 years old, 127 between 40-64 years old, and 78 over 64 years old. Significant age-related alterations were observed in both adaptive and innate immune cell subsets. CD8 + T cells decreased and CD4/CD8 ratio increased, with notable increases in NK cells. CD4 + T cells were less impacted by aging, while CD8 + T cells significantly lost CD28 and increased CD31 expression with age. A clear reverse trend in naïve and memory subsets of CD4 + and CD8 + T cells was observed. Detailed reference ranges for immune cell subsets in healthy Taiwanese adults were established. A systematic review included 7,425 adults and a meta-analysis of 12 eligible studies confirmed our findings in Taiwan, enhancing generalizability.

CONCLUSIONS

Combined with previous studies and original data through a systematic review and meta-analysis, we highlighted and quantified significant immune profile differences between older and younger individuals. The sex and age-specific reference ranges for peripheral immune cell subsets can serve as a basis for effective immune monitoring of various aging-related illnesses.

Bergamot (Citrus bergamia), a (Poly)Phenol-Rich Source for Improving Osteosarcopenic Obesity: A Systematic Review

This systematic review investigates the potential of bergamot, a polyphenol-rich citrus fruit, in improving osteosarcopenic obesity, a condition characterized by the simultaneous presence of osteoporosis, obesity, and sarcopenia. Bergamot extracts have been suggested to possess several pharmacological properties, including anti-inflammatory and antioxidant effects, which could be useful in the management of age-related diseases and neuromuscular health. The review highlights the promising effects of bergamot extracts on skeletal muscle mass and function, particularly in the context of obesity, metabolic syndrome, osteosarcopenic obesity, and osteoporosis. Furthermore, some studies have shown that bergamot extracts can improve the metabolic balance, endothelial function, and maximal oxygen uptake in athletes, highlighting their potential benefits for skeletal muscle health. Taken together, these results suggest that bergamot extracts, especially those rich in polyphenols, may be a valuable adjunct in the management of osteosarcopenic obesity and other associated clinical conditions involving pro-inflammatory effects on organs and tissues.

Advancements in Research on Mesenchymal Stem-Cell-Derived Exosomal miRNAs: A Pivotal Insight into Aging and Age-Related Diseases

Mesenchymal stem cells (MSCs) are capable of differentiating into various cell types and play a crucial role in repairing aging tissues and diseased organs. Aging manifests as a gradual loss of cellular, tissue, and organ function, leading to the progression of pathologies. Exosomes (Exos) are extracellular vesicles secreted by cells, which maintain cellular homeostasis, clear cellular debris, and facilitate communication between cells and organs. This review provides a comprehensive summary of the mechanisms for the synthesis and sorting of MSC-Exo miRNAs and summarizes the current research status of MSCs-Exos in mitigating aging and age-related diseases. It delves into the underlying molecular mechanisms, which encompass antioxidative stress, anti-inflammatory response, and the promotion of angiogenesis. Additionally, this review also discusses potential challenges in and future strategies for advancing MSC-Exo miRNA-based therapies in the treatment of aging and age-related diseases.

Assessing the Impact of Frailty on Infection Risk in Older Adults: Prospective Observational Cohort Study

Background

Infectious diseases are among the leading causes of death and disability and are recognized as a major cause of health loss globally. At the same time, frailty as a geriatric syndrome is a rapidly growing major public health problem. However, few studies have investigated the incidence and risk of infectious diseases in frail older people. Thus, research on frailty and infectious diseases is urgently needed.

Objective

The purpose of this study was to evaluate the association between frailty and infectious diseases among older adults aged 65 years and older.

Methods

In this prospective observational cohort study, we have analyzed the infectious disease prevalence outcomes of older adults aged 65 years and older who participated in frailty epidemiological surveys from March 1, 2018, to March 2023 in Dalang Town, Dongguan City, and from March 1, 2020, to March 2023 in Guancheng Street, Dongguan City. This study has an annual on-site follow-up. Incidence data for infectious diseases were collected through the Chinese Disease Control and Prevention Information System-Infectious Disease Monitoring and Public Health Emergency Monitoring System. A project-developed frailty assessment scale was used to assess the frailty status of study participants. We compared the incidence rate ratios (IRR) of each disease across frailty status, age, and gender to determine the associations among frailty, gender, age, and infectious diseases. Cox proportional hazards regression was conducted to identify the effect of frailty on the risk of demographic factors and frailty on the risk of infectious diseases, with estimations of the hazard ratio and 95% CI.

Results

A total of 235 cases of 12 infectious diseases were reported during the study period, with an incidence of 906.21/100,000 person-years in the frailty group. In the same age group, the risk of infection was higher in men than women. Frail older adults had a hazard ratio for infectious diseases of 1.50 (95% CI 1.14-1.97) compared with healthy older adults. We obtained the same result after sensitivity analyses. For respiratory tract-transmitted diseases (IRR 1.97, 95% CI 1.44-2.71) and gastrointestinal tract-transmitted diseases (IRR 3.67, 95% CI 1.39-10.74), frail older adults are at risk. Whereas no significant association was found for blood-borne, sexually transmitted, and contact-transmitted diseases (IRR 0.76, 95% CI 0.37-1.45).

Conclusions

Our study provides additional evidence that frailty components are significantly associated with infectious diseases. Health care professionals must pay more attention to frailty in infectious disease prevention and control.

Short- and medium-term cumulative effects of traffic-related air pollution on resting heart rate in the elderly: A wearable device study

BACKGROUND

Epidemiological evidence regarding the association between air pollution and resting heart rate (RHR), a predictor of cardiovascular disease and mortality, is limited and inconsistent.

OBJECTIVES

We used wearable devices and time-series analysis to assess the exposure-response relationship over an extended lag period.

METHODS

Ninety-seven elderly individuals (>65 years) from the Taipei Basin participated from May to November 2020 and wore Garmin® smartwatches continuously until the end of 2021 for heart rate monitoring. RHR was defined as the daily average of the lowest 30-min heart rate. Air pollution exposure data, covering lag periods from 0 to 60 days, were obtained from nearby monitoring stations. We used distributed lag non-linear models and linear mixed-effect models to assess cumulative effects of air pollution. Principal component analysis was utilized to explore underlying patterns in air pollution exposure, and subgroup analyses with interaction terms were conducted to explore the modification effects of individual factors.

RESULTS

After adjusting for co-pollutants in the models, an interquartile range increase of 0.18 ppm in carbon monoxide (CO) was consistently associated with increased RHR across lag periods of 0-1 day (0.31, 95 % confidence interval [CI]: 0.24-0.38), 0-7 days (0.68, 95 % CI: 0.57-0.79), and 0-50 days (1.02, 95 % CI: 0.82-1.21). Principal component analysis identified two factors, one primarily influenced by CO and nitrogen dioxide (NO2), indicative of traffic sources. Increases in the varimax-rotated traffic-related score were correlated with higher RHR over 0-1 day (0.36, 95 % CI: 0.25-0.47), 0-7 days (0.62, 95 % CI: 0.46-0.77), and 0-50 days (1.27, 95 % CI: 0.87-1.67) lag periods. Over a 0-7 day lag, RHR responses to traffic pollution were intensified by higher temperatures (β = 0.80 vs. 0.29; interaction p-value [P_int] = 0.011). Males (β = 0.66 vs. 0.60; P_int < 0.0001), hypertensive individuals (β = 0.85 vs. 0.45; P_int = 0.028), diabetics (β = 0.96 vs. 0.52; P_int = 0.042), and those with lower physical activity (β = 0.70 vs. 0.54; P_int < 0.0001) also exhibited stronger responses. Over a 0-50 day lag, males (β = 0.99 vs. 0.96; P_int < 0.0001), diabetics (β = 1.66 vs. 0.69; P_int < 0.0001), individuals with lower physical activity (β = 1.49 vs. 0.47; P_int = 0.0006), and those with fewer steps on lag day 1 (β = 1.17 vs. 0.71; P_int = 0.029) showed amplified responses.

CONCLUSIONS

Prolonged exposure to traffic-related air pollution results in cumulative cardiovascular risks, persisting for up to 50 days. These effects are more pronounced on warmer days and in individuals with chronic conditions or inactive lifestyles.

Immunosenescence: How Aging Increases Susceptibility to Bacterial Infections and Virulence Factors

The process of aging leads to a progressive decline in the immune system function, known as immunosenescence, which compromises both innate and adaptive responses. This includes impairments in phagocytosis and decreased production, activation, and function of T- and B-lymphocytes, among other effects. Bacteria exploit immunosenescence by using various virulence factors to evade the host's defenses, leading to severe and often life-threatening infections. This manuscript explores the complex relationship between immunosenescence and bacterial virulence, focusing on the underlying mechanisms that increase vulnerability to bacterial infections in the elderly. Additionally, it discusses how machine learning methods can provide accurate modeling of interactions between the weakened immune system and bacterial virulence mechanisms, guiding the development of personalized interventions. The development of vaccines, novel antibiotics, and antivirulence therapies for multidrug-resistant bacteria, as well as the investigation of potential immune-boosting therapies, are promising strategies in this field. Future research should focus on how machine learning approaches can be integrated with immunological, microbiological, and clinical data to develop personalized interventions that improve outcomes for bacterial infections in the growing elderly population.

A new model and precious tool to study molecular mechanisms of macrophage aging

The accumulation of senescent cells, characterized by a senescence-associated secretory phenotype (SASP), contributes to chronic inflammation and age-related diseases (ARD). During aging, macrophages can adopt a senescent-like phenotype and an altered function, which promotes senescent cell accumulation. In the context of aging and ARD, controlling the resolution of the inflammatory response and preventing chronic inflammation, especially by targeting macrophages, must be a priority. Aging being a dynamic process, we developed a model of in vitro murine peritoneal macrophage aging. Our results show that macrophages cultured for 7 or 14 days exhibit a senescence-like phenotype: proliferation decrease, the levels of cyclin-dependent kinase inhibitors p16INK4A and p21CIP1 and of pro-inflammatory SASP components (MCP-1, IL-6, IL-1β, TNF-α, and MMP-9) increase, phagocytosis capacity decline and glycolytic activity is induced. In our model, chronic treatment with CB3, a thioredoxin-1 mimetic anti-inflammatory peptide, completely prevents p21CIP1 increase and enables day 14 macrophages to maintain proliferative activity.We describe a new model of macrophage aging with a senescence-like phenotype associated with inflammatory, metabolic and functional perturbations. This model is a valuable tool for characterizing macrophage aging mechanisms and developing innovative strategies with promising therapeutical purpose in limiting inflammaging and ARD.

Inhibitory immune checkpoints suppress the surveillance of senescent cells promoting their accumulation with aging and in age-related diseases

The accumulation of pro-inflammatory senescent cells within tissues is a common hallmark of the aging process and many age-related diseases. This modification has been called the senescence-associated secretory phenotype (SASP) and observed in cultured cells and in cells isolated from aged tissues. Currently, there is a debate whether the accumulation of senescent cells within tissues should be attributed to increased generation of senescent cells or to a defect in their elimination from aging tissues. Emerging studies have revealed that senescent cells display an increased expression of several inhibitory immune checkpoint ligands, especially those of the programmed cell death protein-1 (PD-1) ligand-1 (PD-L1) proteins. It is known that the PD-L1 ligands, especially those of cancer cells, target the PD-1 receptor of cytotoxic CD8+ T and natural killer (NK) cells disturbing their functions, e.g., evoking a decline in their cytotoxic activity and promoting their exhaustion and even apoptosis. An increase in the level of the PD-L1 protein in senescent cells was able to suppress their immune surveillance and inhibit their elimination by cytotoxic CD8+ T and NK cells. Senescent cells are known to express ligands for several inhibitory immune checkpoint receptors, i.e., PD-1, LILRB4, NKG2A, TIM-3, and SIRPα receptors. Here, I will briefly describe those pathways and examine whether these inhibitory checkpoints could be involved in the immune evasion of senescent cells with aging and age-related diseases. It seems plausible that an enhanced inhibitory checkpoint signaling can prevent the elimination of senescent cells from tissues and thus promote the aging process.

Mitigating disuse-induced skeletal muscle atrophy in ageing: Resistance exercise as a critical countermeasure

The gradual deterioration of physiological systems with ageing makes it difficult to maintain skeletal muscle mass (sarcopenia), at least partly due to the presence of 'anabolic resistance', resulting in muscle loss. Sarcopenia can be transiently but markedly accelerated through periods of muscle disuse-induced (i.e., unloading) atrophy due to reduced physical activity, sickness, immobilisation or hospitalisation. Periods of disuse are detrimental to older adults' overall quality of life and substantially increase their risk of falls, physical and social dependence, and early mortality. Disuse events induce skeletal muscle atrophy through various mechanisms, including anabolic resistance, inflammation, disturbed proteostasis and mitochondrial dysfunction, all of which tip the scales in favour of a negative net protein balance and subsequent muscle loss. Concerningly, recovery from disuse atrophy is more difficult for older adults than their younger counterparts. Resistance training (RT) is a potent anabolic stimulus that can robustly stimulate muscle protein synthesis and mitigate muscle losses in older adults when implemented before, during and following unloading. RT may take the form of traditional weightlifting-focused RT, bodyweight training and lower- and higher-load RT. When combined with sufficient dietary protein, RT can accelerate older adults' recovery from a disuse event, mitigate frailty and improve mobility; however, few older adults regularly participate in RT. A feasible and practical approach to improving the accessibility and acceptability of RT is through the use of resistance bands. Moving forward, RT must be prescribed to older adults to mitigate the negative consequences of disuse atrophy.

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.

Deciphering the impact of TERT/telomerase on immunosenescence and T cell revitalization

Immunosenescence impacts both the innate and adaptive immune systems, predominantly affecting certain immune cell types. A notable manifestation of immunosenescence is the diminished efficacy of adaptive immunity. The excessive senescence of immune cells, particularly T cells, leads to marked immune deficiency, consequently escalating the risk of infections, tumors, and age-associated disorders. Lymphocytes, especially T cells, are subject to both replicative and premature senescence. Telomerase reverse transcriptase (TERT) and telomerase have multifaceted roles in regulating cellular behavior, possessing the ability to counteract both replicative and premature senescence in lymphocytes. This review encapsulates recent advancements in understanding immunosenescence, with a focus on T cell senescence, and the regulatory mechanisms involving TERT/telomerase. Additionally, it comprehensively discusses strategies aimed at inhibiting immunosenescence by augmenting TERT/telomerase activity.

Age-associated changes in innate and adaptive immunity: role of the gut microbiota

Aging is generally regarded as an irreversible process, and its intricate relationship with the immune system has garnered significant attention due to its profound implications for the health and well-being of the aging population. As people age, a multitude of alterations occur within the immune system, affecting both innate and adaptive immunity. In the realm of innate immunity, aging brings about changes in the number and function of various immune cells, including neutrophils, monocytes, and macrophages. Additionally, certain immune pathways, like the cGAS-STING, become activated. These alterations can potentially result in telomere damage, the disruption of cytokine signaling, and impaired recognition of pathogens. The adaptive immune system, too, undergoes a myriad of changes as age advances. These include shifts in the number, frequency, subtype, and function of T cells and B cells. Furthermore, the human gut microbiota undergoes dynamic changes as a part of the aging process. Notably, the interplay between immune changes and gut microbiota highlights the gut's role in modulating immune responses and maintaining immune homeostasis. The gut microbiota of centenarians exhibits characteristics akin to those found in young individuals, setting it apart from the microbiota observed in typical elderly individuals. This review delves into the current understanding of how aging impacts the immune system and suggests potential strategies for reversing aging through interventions in immune factors.

Navigating the Neuroimmunomodulation Frontier: Pioneering Approaches and Promising Horizons-A Comprehensive Review

The research in neuroimmunomodulation aims to shed light on the complex relationships that exist between the immune and neurological systems and how they affect the human body. This multidisciplinary field focuses on the way immune responses are influenced by brain activity and how neural function is impacted by immunological signaling. This provides important insights into a range of medical disorders. Targeting both brain and immunological pathways, neuroimmunomodulatory approaches are used in clinical pain management to address chronic pain. Pharmacological therapies aim to modulate neuroimmune interactions and reduce inflammation. Furthermore, bioelectronic techniques like vagus nerve stimulation offer non-invasive control of these systems, while neuromodulation techniques like transcranial magnetic stimulation modify immunological and neuronal responses to reduce pain. Within the context of aging, neuroimmunomodulation analyzes the ways in which immunological and neurological alterations brought on by aging contribute to cognitive decline and neurodegenerative illnesses. Restoring neuroimmune homeostasis through strategies shows promise in reducing age-related cognitive decline. Research into mood disorders focuses on how immunological dysregulation relates to illnesses including anxiety and depression. Immune system fluctuations are increasingly recognized for their impact on brain function, leading to novel treatments that target these interactions. This review emphasizes how interdisciplinary cooperation and continuous research are necessary to better understand the complex relationship between the neurological and immune systems.

Gut microbiota and immunosenescence in cancer

Cancer is generally defined as a disease of aging. With aging, the composition, diversity and functional characteristics of the gut microbiota occur changes, with a decline of beneficial commensal microbes triggered by intrinsic and extrinsic factors (e.g., diet, drugs and chronic health conditions). Nowadays, dysbiosis of the gut microbiota is recognized as a hallmark of cancer. At the same time, aging is accompanied by changes in innate and adaptive immunity, known as immunosenescence, as well as chronic low-grade inflammation, known as inflammaging. The elevated cancer incidence and mortality in the elderly are linked with aging-associated alterations in the gut microbiota that elicit systemic metabolic alterations, leading to immune dysregulation with potentially tumorigenic effects. The gut microbiota and immunosenescence might both affect the response to treatment in cancer patients. In-depth understanding of age-associated alterations in the gut microbiota and immunity will shed light on the risk of cancer development and progression in the elderly. Here, we describe the aging-associated changes of the gut microbiota in cancer, and review the evolving understanding of the gut microbiota-targeted intervention strategies. Furthermore, we summarize the knowledge on the cellular and molecular mechanisms of immunosenescence and its impact on cancer. Finally, we discuss the latest knowledge about the relationships between gut microbiota and immunosenescence, with implications for cancer therapy. Intervention strategies targeting the gut microbiota may attenuate inflammaging and rejuvenate immune function to provide antitumor benefits in elderly patients.

Towards a personalized prediction, prevention and therapy of insomnia: gut microbiota profile can discriminate between paradoxical and objective insomnia in post-menopausal women

Background

Insomnia persists as a prevalent sleep disorder among middle-aged and older adults, significantly impacting quality of life and increasing susceptibility to age-related diseases. It is classified into objective insomnia (O-IN) and paradoxical insomnia (P-IN), where subjective and objective sleep assessments diverge. Current treatment regimens for both patient groups yield unsatisfactory outcomes. Consequently, investigating the neurophysiological distinctions between P-IN and O-IN is imperative for devising novel precision interventions aligned with primary prediction, targeted prevention, and personalized medicine (PPPM) principles.Working hypothesis and methodology.Given the emerging influence of gut microbiota (GM) on sleep physiology via the gut-brain axis, our study focused on characterizing the GM profiles of a well-characterized cohort of 96 Italian postmenopausal women, comprising 54 insomniac patients (18 O-IN and 36 P-IN) and 42 controls, through 16S rRNA amplicon sequencing. Associations were explored with general and clinical history, sleep patterns, stress, hematobiochemical parameters, and nutritional patterns.

Results

Distinctive GM profiles were unveiled between O-IN and P-IN patients. O-IN patients exhibited prominence in the Coriobacteriaceae family, including Collinsella and Adlercreutzia, along with Erysipelotrichaceae, Clostridium, and Pediococcus. Conversely, P-IN patients were mainly discriminated by Bacteroides, Staphylococcus, Carnobacterium, Pseudomonas, and respective families, along with Odoribacter.

Conclusions

These findings provide valuable insights into the microbiota-mediated mechanism of O-IN versus P-IN onset. GM profiling may thus serve as a tailored stratification criterion, enabling the identification of women at risk for specific insomnia subtypes and facilitating the development of integrated microbiota-based predictive diagnostics, targeted prevention, and personalized therapies, ultimately enhancing clinical effectiveness.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13167-024-00369-1.

Relations of optimism and purpose in life to immune markers in aging

OBJECTIVE

Optimism and purpose in life are associated with improved health outcomes. More information is needed on biological mechanisms, including immunosenescence. We investigated if psychological well-being is associated with healthier immunosenescence-related measures including naïve and terminally differentiated CD4+ and CD8+ T cell percentages, CD4+:CD8+, and cytomegalovirus (CMV) IgG response.

METHODS

Participants were adults over age 50 from the Health and Retirement Study. Optimism was measured using the Life Orientation Test Revised. Purpose in life was assessed using the subscale from the Ryff psychological well-being measure. We examined the cross-sectional associations of optimism and purpose in life with measures of T cell subsets using linear regression and with CMV IgG using ordered logit regression, controlling for potential confounding factors.

RESULTS

The final analytic sample ranged from 7250 to 7870. After adjusting for sociodemographic factors, a 1-SD increment in optimism was associated with the percentage of naïve CD4+ T cells increasing by 0.6 (95%CI 0.2%, 1.0%). A 1-SD increment in purpose in life was associated with the percentage of naïve CD4+ T cells increasing by 0.9 (95%CI 0.5%, 1.3%) after adjusting for sociodemographic factors and the association was maintained after further adjustments for health conditions, depression, and health behaviors. For naïve CD8+ T cell percentages, CD4:CD8 ratios, and CMV IgG antibodies, associations were seen only in models that adjusted for age. No significant associations were seen in any models for the terminally differentiated CD4+ and CD8+ T cells.

CONCLUSIONS

We found associations of optimism and purpose in life with naïve CD4+ T cell percentages.

Alterations of receptors and insulin-like growth factor binding proteins in senescent cells

The knowledge about cellular senescence expands dynamically, providing more and more conclusive evidence of its triggers, mechanisms, and consequences. Senescence-associated secretory phenotype (SASP), one of the most important functional traits of senescent cells, is responsible for a large extent of their context-dependent activity. Both SASP's components and signaling pathways are well-defined. A literature review shows, however, that a relatively underinvestigated aspect of senescent cell autocrine and paracrine activity is the change in the production of proteins responsible for the reception and transmission of SASP signals, i.e., receptors and binding proteins. For this reason, we present in this article the current state of knowledge regarding senescence-associated changes in cellular receptors and insulin-like growth factor binding proteins. We also discuss the role of these alterations in senescence induction and maintenance, pro-cancerogenic effects of senescent cells, and aging-related structural and functional malfunctions.

Targeting ferroptosis as a potential prevention and treatment strategy for aging-related diseases

Ferroptosis, an emerging paradigm of programmed cellular necrosis posited in recent years, manifests across a spectrum of maladies with profound implications for human well-being. Numerous investigations substantiate that modulating ferroptosis, whether through inhibition or augmentation, plays a pivotal role in the etiology and control of numerous age-related afflictions, encompassing neurological, circulatory, respiratory, and other disorders. This paper not only summarizes the regulatory mechanisms of ferroptosis, but also discusses the impact of ferroptosis on the biological processes of aging and its role in age-related diseases. Furthermore, it scrutinizes recent therapeutic strides in addressing aging-related conditions through the modulation of ferroptosis. The paper consolidates the existing knowledge on potential applications of ferroptosis-related pharmacotherapies and envisages the translational prospects of ferroptosis-targeted interventions in clinical paradigms.

Understanding the Complex Dynamics of Immunosenescence in Multiple Sclerosis: From Pathogenesis to Treatment

Immunosenescence, the gradual deterioration of immune function with age, holds profound implications for our understanding and management of multiple sclerosis (MS), a chronic autoimmune disease affecting the central nervous system. Traditionally diagnosed in young adults, advancements in disease-modifying therapies and increased life expectancy have led to a growing number of older individuals with MS. This demographic shift underscores the need for a deeper investigation into how age-related alterations in immune function shape the course of MS, influencing disease progression, treatment effectiveness, and overall patient outcomes. Age-related immunosenescence involves changes such as shifts in cytokine profiles, the accumulation of senescent immune cells, and compromised immune surveillance, collectively contributing to a state known as "inflammaging". In the context of MS, these immunological changes disturb the intricate balance between inflammatory and regulatory responses, thereby impacting mechanisms of central immune tolerance and peripheral regulation. This paper stands out by combining the most recent advancements in immunosenescence with both pathophysiological and treatment perspectives on multiple sclerosis, offering a cohesive and accessible discussion that bridges theory and practice, while also introducing novel insights into underexplored concepts such as therapy discontinuation and the latest senolytic, neuroprotective, and remyelination therapies. Enhancing our understanding of these complexities will guide tailored approaches to MS management, ultimately improving clinical outcomes for affected individuals.

Innate immunity in peripheral tissues is differentially impaired under normal and endotoxic conditions in aging

Chronic low-grade inflammation is a hallmark of aging, aka "inflammaging", which is linked to a wide range of age-associated diseases. Immune dysfunction increases disease susceptibility, and increases morbidity and mortality of aging. Innate immune cells, including monocytes, macrophages and neutrophils, are the first responders of host defense and the key mediators of various metabolic and inflammatory insults. Currently, the understanding of innate immune programming in aging is largely fragmented. Here we investigated the phenotypic and functional properties of innate immune cells in various peripheral tissues of young and aged mice under normal and endotoxic conditions. Under the steady state, aged mice showed elevated pro-inflammatory monocytes/macrophages in peripheral blood, adipose tissue, liver, and colon. Under lipopolysaccharide (LPS)-induced inflammatory state, the innate immune cells of aged mice showed a different response to LPS stimulus than that of young mice. LPS-induced immune responses displayed differential profiles in different tissues and cell types. In the peripheral blood, when responding to LPS, the aged mice showed higher neutrophils, but lower pro-inflammatory monocytes than that in young mice. In the peritoneal fluid, while young mice exhibited significantly elevated pro-inflammatory neutrophils and macrophages in response to LPS, aged mice exhibited decreased pro-inflammatory neutrophils and variable cytokine responses in macrophages. In the adipose tissue, LPS induced less infiltrated neutrophils but more infiltrated macrophages in old mice than young mice. In the liver, aged mice showed a more robust increase of pro-inflammatory macrophages compared to that in young mice under LPS stimulation. In colon, macrophages showed relatively mild response to LPS in both young and old mice. We have further tested bone-marrow derived macrophages (BMDM) from young and aged mice, we found that BMDM from aged mice have impaired polarization, displaying higher expression of pro-inflammatory markers than those from young mice. These data collectively suggest that innate immunity in peripheral tissues is impaired in aging, and the dysregulation of immunity is tissue- and cell-dependent. Our findings in the rodent model underscore the complexity of aging immunity. Further investigation is needed to determine whether the immune profile observed in aged mice is applicable in age-associated diseases in humans.

Empirical analysis of health-related behaviors among older Hakka adults: a latent class analysis

Background

Little is known about health-related behaviors of the older Hakka population in China. We aimed to explore the characteristics and correlates of health-related behaviors among older Hakka adults.

Methods

We used data from the China's Health-Related Quality of Life Survey for Older Adults 2018. Latent class analysis (LCA) defined latent classes of health-related behaviors for 1,262 older Hakka adults aged 60 and above. Generalized linear regression and multinomial logistic regression analysis were used to identify factors influencing the number and the latent classes of health-related behaviors, respectively.

Results

The LCA showed that the latent classes could be stratified as the risk group (14.82%), healthy group (55.71%), and inactive group (29.48%). Sex, age, years of education, current residence, living arrangement, average annual household income, and currently employed were associated with the number of healthy behaviors. Compared with the participants in the healthy group, widowed/others (OR = 5.85, 95% CI = 3.27, 10.48), had 15,001-30,000 (OR = 2.05, 95% CI = 1.21, 3.47) and 60,001 or higher (OR = 3.78, 95% CI = 1.26, 11.36) average annual household income, and currently employed (OR = 3.40, 95% CI = 1.99, 5.81) were highly associated with risk group. Additionally, the participants who are widowed/others (OR = 4.30, 95% CI = 2.70, 6.85) and currently employed (OR = 1.95, 95% CI = 1.27, 2.98) were highly associated with the inactive group.

Conclusion

This study identified factors specifically associated with older Hakka adults' health-related behaviors from an LCA perspective. The findings indicate that policymakers should give more attention to older adults living alone and implement practical interventions to promote health-related behaviors among them.

Harnessing immunomodulation to combat sarcopenia: current insights and possible approaches

Sarcopenia is a complex age-associated syndrome of progressive loss of muscle mass and strength. Although this condition is influenced by many factors, age-related changes in immune function including immune cell dynamics, and chronic inflammation contribute to its progression. The complex interplay between the immune system, gut-muscle axis, and autophagy further underscores their important roles in sarcopenia pathogenesis. Immunomodulation has emerged as a promising strategy to counteract sarcopenia. Traditional management approaches to treat sarcopenia including physical exercise and nutritional supplementation, and the emerging technologies of biophysical stimulation demonstrated the importance of immunomodulation and regulation of macrophages and T cells and reduction of chronic inflammation. Treatments to alleviate low-grade inflammation in older adults by modulating gut microbial composition and diversity further combat sarcopenia. Furthermore, some pharmacological interventions, nano-medicine, and cell therapies targeting muscle, gut microbiota, or autophagy present additional avenues for immunomodulation in sarcopenia. This narrative review explores the immunological underpinnings of sarcopenia, elucidating the relationship between the immune system and muscle during ageing. Additionally, the review discusses new areas such as the gut-muscle axis and autophagy, which bridge immune system function and muscle health. Insights into current and potential approaches for sarcopenia management through modulation of the immune system are provided, along with suggestions for future research directions and therapeutic strategies. We aim to guide further investigation into clinical immunological biomarkers and identify indicators for sarcopenia diagnosis and potential treatment targets to combat this condition. We also aim to draw attention to the importance of considering immunomodulation in the clinical management of sarcopenia.

CAR, mGPS and hs-mGPS: What is among them the best gero-biomarker for age-related diseases? And for what clinical application?

The identification of biomarkers linked to the onset, progression, and prevention of age-related diseases (ARD), in the era of personalized medicine, represents the best goal of geroscience. Geroscience has the fundamental role of exploring and identifying the biological mechanisms of aging to suggest interventions capable of stopping/delaying the many pathological conditions and disabilities related to age. Therefore, it has become its key priority, as well as that of clinical practice and research, based on identifying and validating a range of biomarkers, geromarkers, which can be used to diagnostic, prognostic, or predictive clinical purposes. Indeed, geromarkers have, the potential to predict ARD trajectories and facilitate targeted interventions to slow down the related disabilities. Here our attention is paid to the inflammatory indexes (CAR, mGPS, hs-mGPS) linked to the relationship between the plasma levels of two inflammatory analytes, the typical positive protein of the acute phase, and the negative one, i.e. c-reactive protein (CRP) and albumin, respectively. These indexes allow us to understand the magnitude of the two main mechanisms predicted to influence the aging process, including inflammation and immunosenescence, as well as the degree of ARD severity. Evidence on their relationship with ARD is widely reported and discussed, to understand which can represent the best ARD geromarker, and its clinical application.

Inflammaging: The Next Challenge-Exploring the Role of Gut Microbiota, Environmental Factors, and Sex Differences

The term 'inflammaging' has been coined to describe the chronic state of inflammation derived from ongoing cycles of tissue damage and the subsequent immune responses. This inflammatory status contributes to the decline of organs and physiological functions, accelerates the aging process, and increases the risk of age-related illnesses and death. During aging, the gut microbiota (GM) undergoes significant changes, including a decreased diversity of species, a decline in beneficial bacteria, and a rise in proinflammatory ones, resulting in persistent low-grade inflammation. Moreover, environmental factors, such as diet and medications, contribute to age-related changes in GM and immune function, preventing or promoting inflammaging. This narrative review aims to clarify the underlying mechanisms of inflammaging and to specifically investigate the influence of GM and several environmental factors on these mechanisms, while also exploring potential differences related to sex. Moreover, lifestyle and pharmacological interventions will be suggested to promote healthy aging.