Aging Process Research Articles

Dog Aging: A Comprehensive Review of Molecular, Cellular, and Physiological Processes

The aging process is a multifactorial biological phenomenon starting at birth and persisting throughout life, characterized by a decline in physiological functions and adaptability. This decline results in the diminished capacity of aging organisms to respond to environmental changes and stressors, leading to reduced efficiency in metabolic, immune, and hormonal functions. As behavioral flexibility wanes, older individuals face longer recovery times and increased vulnerability to diseases. While early research proposed nine core hallmarks of mammalian aging, recent studies have expanded this framework to twelve key characteristics: epigenetic changes, genomic instability, telomere shortening, loss of proteostasis, altered metabolism, mitochondrial dysfunction, cellular senescence, disrupted intercellular communication, stem cell depletion, immune system dysfunction, accumulation of toxic metabolites, and dysbiosis. Given the growing interest in the aging area, we propose to add a new hallmark: impaired water homeostasis. This potential hallmark could play a critical role in aging processes and might open new directions for future research in the field. This review enhances our understanding of the physiological aspects of aging in dogs, suggesting new clinical intervention strategies to prevent and control issues that may arise from the pathological degeneration of these hallmarks.

What, When, and Why: Viscoelastic Hemostatic Assays and Their Uses in Trauma Resuscitation.

Viscoelastic hemostatic assays (VHAs) have become a valuable tool in guiding transfusion therapy, particularly in trauma care. While various forms of VHA exist, all provide a quantitative assessment of clot kinetics, strength, and dissolution. Studies have demonstrated that VHA can reduce both mortality and utilization of blood products in the general population. Interpreting VHA results requires consideration of specific patient factors, such as age and altered physiological properties as in pregnancy and the process of aging. Further research is needed to establish accurate reference ranges for these specific populations. This review article provides a comprehensive overview of the technical aspects of VHA as well as their clinical uses in trauma resuscitation.

Non-surgical management of BPH: An updated review of current literature and state of the art on natural compounds and medical therapy.

Benign prostatic hyperplasia (BPH) is a common urological disease that is strongly associated with the aging process and can lead to lower urinary tract symptoms (LUTS). LUTS due to BPH can significantly affect the quality of life of many patients. Among the treatments available for BPH to improve symptoms and functional outcomes, drug therapy and surgical therapy are the options of choice. However, for most patients with symptomatic BPH, medical management remains the cornerstone of treatment. Pharmacologic interventions are often preferred as a first approach, being less invasive compared to surgery. Although the medical treatment of BPH is currently defined by the algorithms of international guidelines, the need for a more personalized approach is increasingly recognized given the wide and heterogeneous range of therapeutic options available. A review of medical therapy for BPH was conducted using relevant articles in PubMed, Scopus, and the Cochrane Central Register of Controlled Trials. In this review, all drug treatments currently available on the international market whose efficacy is scientifically proven are reviewed and described (phytotherapy, alpha-blockers, muscarinic receptor antagonists, 5-alpha-reductase inhibitors, combination therapies, etc.). A total of 17 randomized clinical trials were selected for review. Further, 75 studies were included for analysis and discussion. As the treatment landscape continues to evolve, tailoring therapy to individual patient needs and preferences is likely to become increasingly important to ensure that treatment strategies are both effective and meet patient expectations.

Endometrial hyperplasia, benign endometrial tumors and endometrial carcinoma: A review study

Background. During the reproductive phase, the endometrium undergoes cyclical structural changes. Endometrial hyperplasia (EH) is a prevalent condition that arises from a combination of estrogen exposure and insufficient progesterone levels. Endometrial cancer (EC) is the second most common gynecologic malignancy, with the likelihood of EH progressing to EC ranging from 1% to 29%. The objective of this study is to conduct a comprehensive assessment of various forms of endometrial hyperplasia, benign endometrial tumors, and endometrial cancer (EC). Methods. A review of published papers from major databases, including PubMed, Scopus, and Google Scholar, was conducted. The search included original research articles and reviews on EH, benign endometrial tumors, and EC. Case reports, series, and clinical images were excluded. Results. Information on the selected topics was summarized, including epidemiology, etiology, histopathological classification, anatomy, biological and molecular characteristics, detection and prevention, clinical manifestations, staging, diagnostic workup, prognostic factors, and management. Conclusion. Endometrial hyperplasia and endometrial cancer are two of the most common problems in women. EH is a major precancerous condition for EC, and EC is associated with a poor prognosis if diagnosed late. The epidemiology and outcomes of both conditions vary according to several factors, including ethnicity, environment, socioeconomic status, heredity, drugs, hormones, and the aging process.

Insights into the molecular underlying mechanisms and therapeutic potential of endoplasmic reticulum stress in sensorineural hearing loss

Sensorineural hearing loss (SNHL) is characterized by a compromised cochlear perception of sound waves. Major risk factors for SNHL include genetic mutations, exposure to noise, ototoxic medications, and the aging process. Previous research has demonstrated that inflammation, oxidative stress, apoptosis, and autophagy, which are detrimental to inner ear cells, contribute to the pathogenesis of SNHL; however, the precise mechanisms remain inadequately understood. The endoplasmic reticulum (ER) plays a key role in various cellular processes, including protein synthesis, folding, lipid synthesis, cellular calcium and redox homeostasis, and its homeostatic balance is essential to maintain normal cellular function. Accumulation of unfolded or misfolded proteins in the ER leads to endoplasmic reticulum stress (ERS) and activates the unfolded protein response (UPR) signaling pathway. The adaptive UPR has the potential to reestablish protein homeostasis, whereas the maladaptive UPR, associated with inflammation, oxidative stress, apoptosis, and autophagy, can lead to cellular damage and death. Recent evidence increasingly supports the notion that ERS-mediated cellular damage responses play a crucial role in the initiation and progression of various SNHLs. This article reviews the research advancements on ERS in SNHL, with the aim of elucidating molecular biological mechanisms underlying ERS in SNHL and providing novel insights for the treatment.

Telomere Dynamics in Zebrafish Aging and Disease.

Fish telomere lengths vary significantly across the numerous species, implicating diverse life strategies and environmental adaptations. Zebrafish have telomere dynamics that are comparable to humans and are emerging as a key model in which to unravel the systemic effects of telomere shortening on aging and interorgan communication. Here, we discuss zebrafish telomere biology, focusing on the organismal impact of telomere attrition beyond cellular senescence, with particular emphasis on how telomeric shortening in specific tissues can unleash widespread organ dysfunction and disease. This highlights a novel aspect of tissue communication, whereby telomere shortening in one organ can propagate through biological networks, influencing the aging process systemically. These discoveries position zebrafish as a valuable model for studying the complex interactions between telomeres, aging, and tissue cross talk, providing important insights with direct relevance to human health and longevity.

Investigation of Impact of Oxidative Stress on Human Periodontal Ligament Cells Exposed to Static Compression

Oxidative stress (OS) is a common feature of many inflammatory diseases, oral pathologies, and aging processes. The impact of OS on periodontal ligament cells (PDLCs) in relation to oral pathologies, including periodontal diseases, has been investigated in different studies. However, its impact on orthodontic tooth movement (OTM) remains poorly understood. This study used an in vitro model with human PDLCs previously exposed to H2O2 to investigate the effects of OS under a static compressive force which simulated the conditions of OTM. Human PDLCs were treated with varying concentrations of H2O2 to identify sub-lethal doses that affected viability minimally. To mimic compromised conditions resembling OTM under OS, the cells were pretreated with the selected H2O2 concentrations for 24 h. Using an in vitro loading model, a static compressive force (2 g/cm2) was applied for an additional 24 h. The cell viability, proliferation, and cytotoxicity were evaluated using live/dead and resazurin assays. Apoptosis induction was assessed based on caspase-3/7 activity. The gene expression related to bone remodeling (RUNX2, TNFRSF11B/OPG, BGLAP), inflammation (IL6, CXCL8/IL8, PTGS2/COX2), apoptosis (CASP3, CASP8), and autophagy (MAP1LC3A/LC3, BECN1) was analyzed using RT-qPCR. This study suggests an altering effect of previous OS exposure on static-compression-related mechanosensing. Further research is needed to fully elucidate these mechanisms.

A Binary siRNA-Loaded Tetrahedral DNA Nanobox for Synergetic Anti-Aging Therapy.

Extensive accumulation of senescent cells contributes to organismal aging, and slowing down the process of cellular senescence may ameliorate age-related pathologies. Targeted inhibition of the mechanistic target of rapamycin complex 1 (mTORC1) is found to suppress the conversion of cells to senescence. The regulatory-associated protein of mTOR (Raptor), a key component of mTORC1, has been implicated as important in the aging process, and its druggability deserves to be investigated. Due to high efficiency and high convenience in drug construction, siRNA shows great potential in silencing Raptor expression via RNA interfering therapy. Here,we developed a functionalized anti-aging nanoplatform based on tetrahedral DNA nanostructures (TDNs) encapsulating siRNA targeting Raptor for synergistic anti-aging therapy, named siR-TDNbox. Anti-inflammatory and antioxidant properties of TDN beneficially attenuate age-associated inflammation while serving as siRNA nanocarrier, and thus play a binary role. The results suggest that the siR-TDNbox binary therapeutic nanoplatform has demonstrated an excellent ability to delay aging, inhibit mTORC1 signaling, and extend lifespan. This anti-aging nanoplatform may provide a medium for the combined application of traditional senotherapeutic drugs and promote the upgrading of nanomaterials with anti-aging effects.

The Relationship Between Reduced Hand Dexterity and Brain Structure Abnormality in Older Adults

Background: Hand dexterity is affected by normal aging and neuroinflammatory processes in the brain. Understanding the relationship between hand dexterity and brain structure in neurotypical older adults may be informative about prodromal pathological processes, thus providing an opportunity for earlier diagnosis and intervention to improve functional outcomes. Methods: this study investigates the associations between hand dexterity and brain measures in neurotypical older adults (≥65 years) using the Nine-Hole Peg Test (9HPT) and magnetic resonance imaging (MRI). Results: Elastic net regularized regression revealed that reduced hand dexterity in dominant and non-dominant hands was associated with an enlarged volume of the left choroid plexus, the region implicated in neuroinflammatory and altered myelination processes, and reduced myelin content in the left frontal operculum, the region implicated in motor imagery, action production, and higher-order motor functions. Distinct neural mechanisms underlying hand dexterity in dominant and non-dominant hands included the differences in caudate and thalamic volumes as well as altered cortical myelin patterns in frontal, temporal, parietal, and occipital regions supporting sensorimotor and visual processing and integration, attentional control, and eye movements. Although elastic net identified more predictive features for the dominant vs. non-dominant hand, the feature stability was higher for the latter, thus indicating higher generalizability for the non-dominant hand model. Conclusions: Our findings suggest that the 9HPT for hand dexterity might be a cost-effective screening tool for early detection of neuroinflammatory and neurodegenerative processes. Longitudinal studies are needed to validate our findings in a larger sample and explore the potential of hand dexterity as an early clinical marker.

Prosodic changes with age: a longitudinal study with three public figures in European Portuguese

Purpose The analysis of acoustic parameters contributes to the characterisation of human communication development throughout the lifetime. The present paper intends to analyse suprasegmental features of European Portuguese in longitudinal conversational speech samples of three male public figures in uncontrolled environments across different ages, approximately 30 years apart. Participants and methods Twenty prosodic features concerning intonation, intensity, rhythm, and pause measures were extracted semi-automatically from 360 speech intervals (3-4 interviews from each speaker x 30 speech intervals x 3 speakers) lasting between 3 to 6 s. Results Twelve prosodic parameters presented significant age effects at least in one speaker. Group mean comparisons revealed significant differences between the youngest (i.e. 50 years) and the oldest age groups (i.e. 80 years) in seven parameters. The results from the analysis point to a lower and less variable fo, higher fo minimum, wider fo peaks, more vocal effort and more variable global intensity, slower speech and articulation rate, and also more frequent and longer pauses in older ages. Conclusion This longitudinal study has the potential to contribute to the characterization of the normal aging process, proving to be significant in the domains of human-machine communication, speech recognition systems, applied linguistics, or the implementation of strategies in communicative contexts with older adults

Physical Aging Process in 20-Year-Old Polylactide Bottles

Physical Aging Process in 20-Year-Old Polylactide Bottles

Effect of Hygrothermal Aging on the Decomposition Reactions of Magnesium/Teflon/Viton (MTV) Pyrotechnic

ABSTRACTMagnesium/Teflon/Viton (MTV) pyrotechnic compositions are widely used in various applications. Magnesium is known to oxidize under elevated humidity and temperature conditions. Consequently, the performance of MTV pyrotechnics degrades as they age. Accurate characterization of the aging process is necessary for the prediction of storage life and performance of MTV pyrotechnics. This study investigates the hygrothermal aging of an MTV pyrotechnic mixture using accelerated aging, thermogravimetry (TG), differential scanning calorimetry (DSC), and differential thermal analysis (DTA). The kinetic parameters were obtained using the Friedman isoconversional method. Differential TG (DTG) curves were analyzed to identify the reaction steps occurring during the decomposition of pristine and aged MTV samples. Scanning electron microscope–electron‐dispersive spectroscopy (SEM–EDS) and Fourier transform infrared (FTIR) spectroscopy revealed changes in morphology and chemical composition. As expected, increased humidity caused significant degradation of the metallic fuel in the MTV pyrotechnic. Furthermore, the formation of unwanted compounds due to aging was clearly observed. The formation of these compounds, in addition to the depletion of the metallic fuel, was realized to be the cause of reduced the performance of aged MTV pyrotechnics.

Plane Problem of Impact on Composite Two-Layer Material Reinforced by Crystalline Fibers

A generalized approach was developed for solving contact problems in a dynamic elastic-plastic formulation. For the design of composite and reinforced materials, a technique for solving dynamic contact problems in more adequate an elastic-plastic mathematical formulation is used. To consider the physical nonlinearity of the deformation process, the method of successive approximations is used, which makes it possible to reduce the nonlinear problem to a solution of the sequences of linear problems. The problem of a plane strain state of a beam made from the composite reinforced two-layer material is being solved. The reinforced or armed composite material consists of three materials: metal of top thin layer, the main material of glass and the reinforcing crystalline seven fibers of basalt. Glass is a non-crystalline, often transparent amorphous solid, that has widespread practical and technological use in the modern industry. Glass has high strength and is not affected by the processes of aging of the material, corrosion, and creep. In addition, this material is cheap and widely available. The reinforced composite beam is rigidly linked to an absolutely solid base and on which an absolutely solid impactor acts from above in the centre on a different size of the area of initial contact.

Subject-Level Segmentation Precision Weights for Volumetric Studies Involving Label Fusion.

In neuroimaging research, volumetric data contribute valuable information for understanding brain changes during both healthy aging and pathological processes. Extracting these measures from images requires segmenting the regions of interest (ROIs), and many popular methods accomplish this by fusing labels from multiple expert-segmented images called atlases. However, post-segmentation, current practices typically treat each subject's measurement equally without incorporating any information about variation in their segmentation precision. This naïve approach hinders comparing ROI volumes between different samples to identify associations between tissue volume and disease or phenotype. We propose a novel method that estimates the variance of the measured ROI volume for each subject due to the multi-atlas segmentation procedure. We demonstrate in real data that weighting by these estimates markedly improves the power to detect a mean difference in hippocampal volume between controls and subjects with mild cognitive impairment or Alzheimer's disease.

Colorimetric changes of zirconia-reinforced lithium disilicate with varied thicknesses under UV aging conditions

Background. Zirconia-reinforced lithium disilicate (ZLD) is a promising material for esthetic dental restorations due to its strength, translucency, and color stability. However, its durability under accelerated aging conditions needs further investigation. The present in vitro study evaluated the effect of UV accelerated aging on the translucency and color stability of ZLD at varying thicknesses, using IPS e.max Press (LD) as a reference. Methods. Seventy-two samples were divided into two groups: high translucent (HT) Vita Ambria (ZLD) and IPS e.max Press (LD) (n=36, each). Each group was further subdivided into four thicknesses: 0.5, 1.0, 1.5, and 2.0 mm (n=9). The samples were fabricated, polished, and subjected to UV weathering for 384 hours, simulating one year of clinical service. Translucency and color changes were assessed using a spectrophotometer. Data were analyzed using SPSS 20, with independent t-test, paired t-test, and one-way ANOVA at a significance level of P≤0.05. Results. Vita Ambria exhibited significantly higher translucency before and after aging compared to IPS e.max press at all thicknesses (P=0.000). In both materials, translucency decreased when the thickness increased (P=0.000), observed before and after UV aging. Vita Ambria also displayed a greater color change (ΔE=2000) compared to IPS e.max press across all thicknesses (P=0.000). Conclusion. ZLD exhibited higher translucency than LD before and after accelerated artificial aging, indicating that the accelerated aging process adversely impacted the optical properties of the tested material. However, LD demonstrated superior color stability.

Senescence of endothelial cells increases susceptibility to Kaposi's sarcoma-associated herpesvirus infection via CD109-mediated viral entry.

The aging process is characterized by cellular functional decline and increased susceptibility to infections. Understanding the association between virus infection and aging is crucial for developing effective strategies against viral infections in older individuals. However, the relationship between Kaposi's sarcoma-associated herpesvirus (KSHV) infection, a cause of Kaposi's sarcoma prevalent among the elderly without HIV infection, and cellular senescence remains enigmatic. This study uncovers a fascinating link between cellular senescence and enhanced KSHV infectivity in human endothelial cells. Through a comprehensive proteomic analysis, we identified caveolin-1 and CD109 as novel host factors significantly upregulated in senescent cells that promote KSHV infection. Remarkably, CRISPR-Cas9-mediated knockout of these factors reduced KSHV binding and entry, leading to decreased viral infectivity. Furthermore, surface plasmon resonance analysis and confocal microscopy revealed a direct interaction between KSHV virions and CD109 on the cell surface during entry, with recombinant CD109 protein exhibiting an intriguing ability to inhibit infection by blocking virion binding. These findings uncover a previously unrecognized role of cellular senescence in enhancing KSHV infection through upregulation of specific host factors and provide novel insights into the complex interplay between aging and viral pathogenesis.

The impact of COVID-19 on accelerating of immunosenescence and brain aging

The COVID-19 pandemic, caused by the novel coronavirus SARS-CoV-2, has profoundly impacted global health, affecting not only the immediate morbidity and mortality rates but also long-term health outcomes across various populations. Although the acute effects of COVID-19 on the respiratory system have initially been the primary focus, it is increasingly evident that the virus can have significant impacts on multiple physiological systems, including the nervous and immune systems. The pandemic has highlighted the complex interplay between viral infection, immune aging, and brain health, that can potentially accelerate neuroimmune aging and contribute to the persistence of long COVID conditions. By inducing chronic inflammation, immunosenescence, and neuroinflammation, COVID-19 may exacerbate the processes of neuroimmune aging, leading to increased risks of cognitive decline, neurodegenerative diseases, and impaired immune function. Key factors include chronic immune dysregulation, oxidative stress, neuroinflammation, and the disruption of cellular processes. These overlapping mechanisms between aging and COVID-19 illustrate how the virus can induce and accelerate aging-related processes, leading to an increased risk of neurodegenerative diseases and other age-related conditions. This mini-review examines key features and possible mechanisms of COVID-19-induced neuroimmune aging that may contribute to the persistence and severity of long COVID. Understanding these interactions is crucial for developing effective interventions. Anti-inflammatory therapies, neuroprotective agents, immunomodulatory treatments, and lifestyle interventions all hold potential for mitigating the long-term effects of the virus. By addressing these challenges, we can improve health outcomes and quality of life for millions affected by the pandemic.

Simulation of the Steady Mixing State of Black Carbon With a Two‐Dimensional Sectional Model

AbstractBlack carbon (BC) strongly absorbs solar radiation and has a warming effect on the earth‐atmosphere system. BC experiences continuous aging, making its optical properties a great uncertainty due to the complex mixing state. To address this issue, we developed a sectional model which is capable of tracking both the aerosol size and the BC core size. This model was applied to simulate BC aging process. The atmospheric observational data from a slightly polluted case was employed to drive the model. It is shown that BC's characteristics tend to reach a steady state within 12 hr. Our analysis reveals that, in the steady state, the size distribution of BC‐containing particles demonstrates a notable characteristic: the particle size distribution decreases exponentially as the particle size increases. This exponential relationship provides a simplified yet accurate representation of the complex BC mixing state. This steady‐state size distribution of BC‐containing particles is validated across diverse atmospheric conditions.

Effects of Biological and Enzymatic Ageing on the Surface Properties of Mg-modified Biochar

The excellent surface properties of Mg-modified biochar have highlighted a broad application prospect for soil heavy metal mitigation. However, the soil biotic aging process can have an impact on the physical and chemical properties of biochar as well as the heavy metal removal performance. Therefore, MgCl2-modified biochar was subjected to a six-month microbial and enzymatically aged test to explore the effects of different biotic aging processes on the physical and chemical properties. The Pb2+ adsorption performance of Mg-modified biochar that experienced different aging processes was compared using isothermal adsorption experiments. The results showed that after microbial aging, the Mg-modified biochar pyrolyzed at 700 ℃ displayed a low persistent free radical signal, with the biofilm secreted by microorganisms wrapped on the surface of the biochar, leading to the increase in the oxygen-containing functional groups on the biochar surface and the increase in the maximum adsorption capacity of Pb2+ from 55.31 mg·g-1 to 86.27 mg·g-1. In contrast, a higher free radical signal of 500 ℃ pyrolyzed biochar suggested that the free radical inhibited the growth and reproduction of microorganisms on the biochar surface, resulting in an insignificant enhancement in maximum adsorption capacity to Pb2+ compared to that with unmodified biochar. The pores of the Mg-modified biochar were severely damaged during the enzymatically aged process, resulting in a decrease in the adsorption capacity of Pb2+ to 22.18 mg·g-1, which was significantly lower than that of the unmodified biochar. Therefore, the adsorption capacity of microbially aged Mg-modified biochar is superior to that of enzymatically aged Mg-modified biochar, mainly because the oxygen-containing functional groups exhibited on the surface of the biochar covered by microorganisms come from the extracellular secretions of microorganisms, which promote the removal of Pb2+.

Integrating Acceptance and Commitment Therapy with Selective Optimization with Compensation to Predict Wellbeing

ABSTRACT Objectives Selective Optimization with Compensation (SOC) is an empirically supported model of successful aging. Acceptance and Commitment Therapy (ACT) is an empirically supported intervention that has a theoretical model which is complementary to the SOC model. Combining the two models can provide a more comprehensive view of successful aging. The relationships between key SOC and ACT variables in relation to age-related wellbeing were explored among a sample of older American adults. Methods Older adult participants (n = 87) were recruited online from social media sites. This sample size provided sufficient power to test hypotheses. Participants completed measures of demographic characteristics, ACT constructs (acceptance, defusion, present-moment-awareness, self-as-context, values), SOC utilization, geriatric morale, purpose in life, and quality of life. Results Acceptance and defusion were significantly correlated with SOC variables and wellbeing. Acceptance and defusion mediated the relationship between SOC utilization and age-related wellbeing. Conclusions Acceptance and defusion were associated with better adjustment to the potential losses that co-occur with aging. Acceptance and defusion may also promote more openness to making changes in daily behaviors that can permit optimization and compensation of age-related losses. Clinical Implications Interventions that promote acceptance and defusion may be promising for older adults as they navigate the aging process.