Model of Accelerated Aging in CB6F2 Mice Induced by Ionizing Radiation.

A model for accelerated aging in mice was developed: CB6F2 mice aged 39-45 days were exposed to fractionated 4-fold relatively uniform γ-radiation (137Cs, 0.98 Gy/min) at a total dose of 6.8 Gy. Radiation exposure led to delayed active growth, leukopenia, and lymphopenia for over 1 year during the post-radiation period. The death of irradiated males and females occurred significantly earlier than in control group animals. Median lifespans in the experimental group were 35-38% lower than in the control group (p<0.001). Ionizing radiation exposure led to the early development of hair depigmentation, cachexia, and the development of aging-associated diseases. In irradiated mice, oncological pathology constituted 30-35% in the mortality structure, which is twice as often as in the control group. The developed model can be used to study the pathogenesis of accelerated aging under radiation exposure and the search for means of its prevention and treatment.

Joint association of diabetes mellitus and inflammation status with biological ageing acceleration and premature mortality.

BACKGROUND: We aimed to investigate the associations of diabetes mellitus (DM) and C-reactive protein (CRP) with biological ageing acceleration and mortality risk. METHODS: We analyzed data from 41,634 adults with CRP and DM at baseline. Subjects were categorized into high CRP (>3 mg/L) and low CRP (≤3 mg/L) groups. The cross-sectional endpoints of the study were biological ageing indicators Klemera-Doubal method BioAge acceleration (KDMAccel) and Phenotypic age acceleration (PhenoAgeAccel), and the follow-up endpoints were all-cause mortality and cardiovascular mortality. RESULTS: In adults with high CRP, compared with those without DM, PhenoAgeAccel increased by 1.66 years (95 % CI: 1.38-1.93), and 8.74 years (95 % CI: 8.25-9.22) in adults with prediabetes and DM, respectively (p for interaction <0.001). Using the CRPlow/non-DM group as a reference, adults in the CRPhigh/non-DM, CRPlow/DM, and CRPhigh/DM groups had significantly advanced biological ageing. Compared to adults without DM, low CRP, and no ageing acceleration, the multivariable-adjusted HRs (95%CIs) of all-cause and cardiovascular mortality in those with DM, CRP, and ageing acceleration were 3.22 (2.79-3.72), and 3.57 (2.81-4.54), respectively. CONCLUSIONS: These findings suggest that the joint presence of low-grade inflammation and DM might be associated with higher odds of biological ageing acceleration and premature mortality.

[Economic index - predictor of premature aging.]

It is widely known that in economically developed countries there is an increase in the proportion of older people. However, the problem of the influence of territorial features of economic development on the rate of population aging is not sufficiently covered. The goal was to study the impact of economic development indicators (EDI) on the processes of premature aging of the population. The materials were statistical collections of the Ministry of Health of Russia and Russian Statistics Service for 2011-2019. The highest incidence was characteristic of cataracts and glaucoma. A direct correlation has been established between the EDI and the age-specific incidence index (ASII) of cataracts (r=0,31; p=0,00436). A group of regions with a high level of economic development was characterized by a higher value of ASII, which, as a rule, corresponds to the later development of the disease.

[Chronic kidney disease and accelerated aging: the role of comprehensive geriatric assessment.]

This review presents data from the literature on the characteristics of the course of chronic kidney disease from the perspective of the geriatric patient. Chronic kidney disease and progression of renal failure is a prototype model of premature and accelerated aging. Many authors have stated that a better mechanistic understanding of the phenomenon of premature aging, early diagnosis of chronic kidney disease, and a geriatric approach to the patient can improve the effectiveness of management and prolongation of life in this category of patients. Comprehensive geriatric assessment is one of the most important tools used by geriatricians and their teams to globally assess elderly patients and plan effective interventions. It is concluded that the use of comprehensive geriatric assessment in patients with chronic kidney disease may improve the clinical status of patients and allow selection of patients who may benefit most from renal replacement therapy compared to a conservative approach. And even in the early stages of chronic kidney disease, a comprehensive geriatric assessment may be useful in formulating a complete intervention plan and optimizing quality of life, autonomy, and prognosis. However, despite recognition of the importance of comprehensive geriatric assessment, the means to implement this tool in nephrology departments have not been developed and require special training programs and appropriate skills. It is concluded that much more needs to be done to realize the continuity of nephrologists and geriatricians in the provision of meaningful skilled care to older patients with chronic kidney disease.

The Detrimental Effects of Bedrest: Premature Cardiovascular Aging and Dysfunction.

Bedrest as an experimental paradigm or as an in-patient stay for medical reasons has negative consequences for cardiovascular health. The effects of severe inactivity parallel many of the changes experienced with natural aging but over a much shorter duration. Cardiac function is reduced, arteries stiffen, neural reflex responses are impaired, and metabolic and oxidative stress responses impose burden on the heart and vascular systems. The effect of these changes is revealed in studies of integrative function. Aerobic fitness progressively deteriorates with bedrest and tolerance of upright posture is rapidly impaired. In this review we consider the similarities of aging and bedrest-induced cardiovascular deconditioning. We concur with many recent clinical recommendations that early and regular mobility with upright posture will reduce likelihood of hospital-associated disability related to bedrest.

Plant Foods Intake and Risk of Premature Aging in Adult Survivors of Childhood Cancer in the St Jude Lifetime Cohort (SJLIFE).

PURPOSE: To identify dietary factors that are related to premature aging in adult survivors of childhood cancer, we examined the associations between plant food intakes and age-related deficit accumulation. METHODS: A total of 3,322 childhood cancer survivors (age 18-65 years, mean = 31, standard deviation = 8.4) in the St Jude Lifetime Cohort had total fruit, total vegetables and subgroups, whole grains, refined grains, nuts/seeds, and nutrients intake assessed using a food frequency questionnaire. Premature aging at baseline was assessed by the deficit accumulation index (DAI) and categorized as low, medium, and high risk. Multinomial logistic regressions (reference: low risk) adjusting for confounders estimated odds ratios (ORs) and 95% CIs. Multivariable linear regression of a continuous intake against a continuous DAI was also performed. RESULTS: Dark green vegetable (ORhigh v low = 0.47 [95% CI, 0.28 to 0.78] per 1/2 cup/1,000 kcal increment) and nuts/seeds intakes (ORhigh v low = 0.71 [95% CI, 0.47 to 1.08] per 1 oz/1,000 kcal increment; coefficientlinear = -0.0115, P = .02) were associated with a lower risk of premature aging. Conversely, refined grain intake was related to an increased risk of premature aging (ORhigh v low = 1.33 [95% CI, 0.99 to 1.78], per 1 oz/1,000 kcal increment; coefficientlinear = 0.0093, P = .005). Fruit and whole grain intakes were not associated with premature aging risk. Among nutrients abundant in plant foods, dietary folate intake was associated with a lower risk of premature aging (ORhigh v low = 0.89 [95% CI, 0.80 to 0.99] per 50 mcg/1,000 kcal increase). Beta-carotene, lutein/zeaxanthin, and vitamin E intakes from foods were also related to a modestly lower, but not statistically significant, risk of premature aging. CONCLUSION: Specific plant foods are associated with lower risk of premature aging, providing targets for the interventions to promote healthy aging in childhood cancer survivors.

Lower socioeconomic status is associated with premature brain aging.

BACKGROUND: Premature age-related brain changes may be influenced by physical health factors. Lower socioeconomic status (SES) is often associated with poorer physical health. In this study, we aimed to investigate the relationship between SES and premature brain aging. METHODS: Brain age was estimated from T1-weighted images using BrainAgeR in 217 participants from the ABC@UofSC Repository. The difference between brain and chronological age (BrainGAP) was calculated. Multiple regression models were used to predict BrainGAP with age, SES, body mass index, diabetes, hypertension, sex, race, and education as predictors. SES was calculated from size-adjusted household income and the cost of living. RESULTS: Fifty-five participants (25.35%) had greater brain age than chronological age (premature brain aging). Multiple regression models revealed that age, sex, and SES were significant predictors of BrainGAP with lower SES associated with greater BrainGAP (premature brain aging). CONCLUSIONS: This study demonstrates that lower SES is an independent contributor to premature brain aging. This may provide additional insight into the mechanisms associated with brain health, cognition, and resilience to neurological injury.

[Chronic obstructive pulmonary disease as a model of premature aging: the pathogenetic role of mitochondria.]

Chronic obstructive pulmonary disease (COPD) is a disease with typical features of premature aging. Modern theories of the pathogenesis of COPD include a number of interrelated concepts that dominate in different time periods. In this work, based on the analysis of the results of our own and published scientific studies, it is demonstrated that the mitochondria-mediated component seems to be the link of most of the recognized theories of the pathogenesis of COPD as a model of early premature aging. The issues of mitochondrial involvement in the pathogenesis of COPD are actively studied, but are not fully understood and do not always have an unambiguous interpretation. The paper systematizes information on the contribution of mitochondrial dysfunction to various aspects of the pathogenesis of COPD, including the relationship between inflammation, hypoxia, oxidative stress, protease imbalance, damage to tissue and cellular phenotype with reprogramming of metabolism and accumulation of a pool of cells with an «aged¼ phenotype. Observations suggest that mitochondrial dysfunction may be a key factor contributing to the initiation and progression of COPD, the accumulation of systemic effects, the formation of comorbidity, and premature aging. The argumentation of this concept provides an evidence-based basis for the development of promising, pathogenetically substantiated targeted strategies for the prevention and control of COPD at the topical and systemic levels.

Dose-dependent relationship between social drinking and brain aging.

Low-level alcohol consumption is commonly perceived as being inconsequential or even beneficial for overall health, with some reports suggesting that it may protect against dementia or cardiovascular risks. However, these potential benefits do not preclude the concurrent possibility of negative health outcomes related to alcohol consumption. To examine whether casual, non-heavy drinking is associated with premature brain aging, we utilized the Brain-Age Regression Analysis and Computational Utility Software package to predict brain age in a community sample of adults [n = 240, mean age 35.1 (±10.7) years, 48% male, 49% African American]. Accelerated brain aging was operationalized as the difference between predicted and chronological age ("brain age gap"). Multiple regression analysis revealed a significant association between previous 90-day alcohol consumption and brain age gap (ß = 0.014, p = 0.023). We replicated these results in an independent cohort [n = 231 adults, mean age 34.3 (±11.1) years, 55% male, 28% African American: ß = 0.014, p = 0.002]. Our results suggest that even low-level alcohol consumption is associated with premature brain aging. The clinical significance of these findings remains to be investigated.

Premature Senescence and Telomere Shortening Induced by Oxidative Stress From Oxalate, Calcium Oxalate Monohydrate, and Urine From Patients With Calcium Oxalate Nephrolithiasis.

Oxidative stress, a well-known cause of stress-induced premature senescence (SIPS), is increased in patients with calcium oxalate (CaOx) kidney stones (KS). Oxalate and calcium oxalate monohydrate (COM) induce oxidative stress in renal tubular cells, but to our knowledge, their effect on SIPS has not yet been examined. Here, we examined whether oxalate, COM, or urine from patients with CaOx KS could induce SIPS and telomere shortening in human kidney (HK)-2 cells, a proximal tubular renal cell line. Urine from age- and sex-matched individuals without stones was used as a control. In sublethal amounts, H2O2, oxalate, COM, and urine from those with KS evoked oxidative stress in HK-2 cells, indicated by increased protein carbonyl content and decreased total antioxidant capacity, but urine from those without stones did not. The proportion of senescent HK-2 cells, as indicated by SA-ßgal staining, increased after treatment with H2O2, oxalate, COM, and urine from those with KS. Expression of p16 was higher in HK-2 cells treated with H2O2, oxalate, COM, and urine from those with KS than it was in cells treated with urine from those without stones and untreated controls. p16 was upregulated in the SA-ßgal positive cells. Relative telomere length was shorter in HK-2 cells treated with H2O2, oxalate, COM, and urine from those with KS than that in cells treated with urine from those without stones and untreated controls. Transcript expression of shelterin components (TRF1, TRF2 and POT1) was decreased in HK-2 cells treated with H2O2, oxalate, COM, and urine from those with KS, in which case the expression was highest. Urine from those without KS did not significantly alter TRF1, TRF2, and POT1 mRNA expression in HK-2 cells relative to untreated controls. In conclusion, oxalate, COM, and urine from patients with CaOx KS induced SIPS and telomere shortening in renal tubular cells. SIPS induced by a lithogenic milieu may result from upregulation of p16 and downregulation of shelterin components, specifically POT1, and might contribute, at least in part, to the development of CaOx KS.

Systems toxicology study reveals reduced impact of heated tobacco product aerosol extract relative to cigarette smoke on premature aging and exacerbation effects in aged aortic cells in vitro.

Aging and smoking are major risk factors for cardiovascular diseases (CVD). Our in vitro study compared, in the context of aging, the effects of the aerosol of Tobacco Heating System 2.2 (THS; an electrically heated tobacco product) and 3R4F reference cigarette smoke (CS) on processes that contribute to vascular pathomechanisms leading to CVD. Young and old human aortic smooth muscle cells (HAoSMC) were exposed to various concentrations of aqueous extracts (AE) from 3R4F CS [0.014-0.22 puffs/mL] or THS aerosol [0.11-1.76 puffs/mL] for 24 h. Key markers were measured by high-content imaging, transcriptomics profiling and multianalyte profiling. In our study, in vitro aging increased senescence, DNA damage, and inflammation and decreased proliferation in the HAoSMCs. At higher concentrations of 3R4F AE, young HAoSMCs behaved similarly to aged cells, while old HAoSMCs showed additional DNA damage and apoptosis effects. At 3R4F AE concentrations with the maximum effect, the THS AE showed no significant effect in young or old HAoSMCs. It required an approximately ten-fold higher concentration of THS AE to induce effects similar to those observed with 3R4F. These effects were independent of nicotine, which did not show a significant effect on HAoSMCs at any tested concentration. Our results show that 3R4F AE accelerates aging in young HAoSMCs and exacerbates the aging effect in old HAoSMCs in vitro, consistent with CS-related contributions to the risk of CVD. Relative to 3R4F AE, the THS AE showed a significantly reduced impact on HAoSMCs, suggesting its lower risk for vascular SMC-associated pathomechanisms leading to CVD.

Association of Epilepsy Surgery With Changes in Imaging-Defined Brain Age.

OBJECTIVE: To determine whether surgery in patients with mesial temporal lobe epilepsy (mTLE) is associated with reduced brain-predicted age as a neural marker overall brain health, we compared brain-predicted and chronologic age difference (brain age gap estimation [BrainAGE]) in patients before and after surgery with healthy controls. METHODS: We acquired 3D T1-weighted MRI scans for 48 patients with mTLE before and after temporal lobe surgery to estimate brain age using a gaussian processes regression model. We examined BrainAGE before and after surgery controlling for brain volume change, comparing patients to 37 age- and sex-matched controls. RESULTS: Preoperatively, patients showed an increased BrainAGE of more than 7 years compared to controls. However, surgery was associated with a mean BrainAGE reduction of 5 years irrespective of whether or not surgery resulted in complete seizure freedom. We observed a lateralization effect as patients with left mTLE had BrainAGE values that more closely resembled control group values following surgery. CONCLUSIONS: Our findings suggest that while morphologic brain alterations linked to accelerated aging have been observed in mTLE, surgery may be associated with changes that reverse such alterations in some patients. This work highlights the advantages of resective surgery on overall brain health in patients with refractory focal epilepsy.

Obesity as a Risk Factor for Accelerated Brain Ageing in First-Episode Psychosis-A Longitudinal Study.

BACKGROUND: Obesity is highly prevalent in schizophrenia, with implications for psychiatric prognosis, possibly through links between obesity and brain structure. In this longitudinal study in first episode of psychosis (FEP), we used machine learning and structural magnetic resonance imaging (MRI) to study the impact of psychotic illness and obesity on brain ageing/neuroprogression shortly after illness onset. METHODS: We acquired 2 prospective MRI scans on average 1.61 years apart in 183 FEP and 155 control individuals. We used a machine learning model trained on an independent sample of 504 controls to estimate the individual brain ages of study participants and calculated BrainAGE by subtracting chronological from the estimated brain age. RESULTS: Individuals with FEP had a higher initial BrainAGE than controls (3.39 ± 6.36 vs 1.72 ± 5.56 years; ß = 1.68, t(336) = 2.59, P = .01), but similar annual rates of brain ageing over time (1.28 ± 2.40 vs 1.07±1.74 estimated years/actual year; t(333) = 0.93, P = .18). Across both cohorts, greater baseline body mass index (BMI) predicted faster brain ageing (ß = 0.08, t(333) = 2.59, P = .01). For each additional BMI point, the brain aged by an additional month per year. Worsening of functioning over time (Global Assessment of Functioning; ß = -0.04, t(164) = -2.48, P = .01) and increases especially in negative symptoms on the Positive and Negative Syndrome Scale (ß = 0.11, t(175) = 3.11, P = .002) were associated with faster brain ageing in FEP. CONCLUSIONS: Brain alterations in psychosis are manifest already during the first episode and over time get worse in those with worsening clinical outcomes or higher baseline BMI. As baseline BMI predicted faster brain ageing, obesity may represent a modifiable risk factor in FEP that is linked with psychiatric outcomes via effects on brain structure.

The stage-specifically accelerated brain aging in never-treated first-episode patients with depression.

Depression associated with structural brain abnormalities is hypothesized to be related with accelerated brain aging. However, there is far from a unified conclusion because of clinical variations such as medication status, cumulative illness burden. To explore whether brain age is accelerated in never-treated first-episode patients with depression and its association with clinical characteristics, we constructed a prediction model where gray matter volumes measured by voxel-based morphometry derived from T1-weighted MRI scans were treated as features. The prediction model was first validated using healthy controls (HCs) in two Chinese Han datasets (Dataset 1, N = 130 for HCs and N = 195 for patients with depression; Dataset 2, N = 270 for HCs) separately or jointly, then the trained prediction model using HCs (N = 400) was applied to never-treated first-episode patients with depression (N = 195). The brain-predicted age difference (brain-PAD) scores defined as the difference between predicted brain age and chronological age, were calculated for all participants and compared between patients with age-, gender-, educational level-matched HCs in Dataset 1. Overall, patients presented higher brain-PAD scores suggesting patients with depression having an "older" brain than expected. More specially, this difference occurred at illness onset (illness duration <3 months) and following 2 years then disappeared as the illness further advanced (>2 years) in patients. This phenomenon was verified by another data-driven method and significant correlation between brain-PAD scores and illness duration in patients. Our results reveal that accelerated brain aging occurs at illness onset and suggest it is a stage-dependent phenomenon in depression.

Reductions in Gray Matter Linked to Epigenetic HIV-Associated Accelerated Aging.

A growing literature suggests a relationship between HIV-infection and a molecular profile of age acceleration. However, despite the widely known high prevalence of HIV-related brain atrophy and HIV-associated neurocognitive disorder (HAND), epigenetic age acceleration has not been linked to HIV-related changes in structural MRI. We applied morphological MRI methods to study the brain structure of 110 virally suppressed participants with HIV infection and 122 uninfected controls age 22-72. All participants were assessed for cognitive impairment, and blood samples were collected from a subset of 86 participants with HIV and 83 controls to estimate epigenetic age. We examined the group-level interactive effects of HIV and chronological age and then used individual estimations of epigenetic age to understand the relationship between age acceleration and brain structure. Finally, we studied the effects of HAND. HIV-infection was related to gray matter reductions, independent of age. However, using epigenetic age as a biomarker for age acceleration, individual HIV-related age acceleration was associated with reductions in total gray matter. HAND was associated with decreases in thalamic and hippocampal gray matter. In conclusion, despite viral suppression, accentuated gray matter loss is evident with HIV-infection, and greater biological age acceleration specifically relates to such gray matter loss.

Aging faster: worry and rumination in late life are associated with greater brain age.

Older adults with anxiety have lower gray matter brain volume-a component of accelerated aging. We have previously validated a machine learning model to predict brain age, an estimate of an individual's age based on voxel-wise gray matter images. We investigated associations between brain age and anxiety, depression, stress, and emotion regulation. We recruited 78 participants (≥50 years) along a wide range of worry severity. We collected imaging data and computed voxel-wise gray matter images, which were input into an existing machine learning model to estimate brain age. We conducted a multivariable linear regression between brain age and age, sex, race, education, worry, anxiety, depression, rumination, neuroticism, stress, reappraisal, and suppression. We found that greater brain age was significantly associated with greater age, male sex, greater worry, greater rumination, and lower suppression. Male sex, worry, and rumination are associated with accelerated aging in late life and expressive suppression may have a protective effect. These results provide evidence for the transdiagnostic model of negative repetitive thoughts, which are associated with cognitive decline, amyloid, and tau.

Prenatal Hypoxia Induces Premature Aging Accompanied by Impaired Function of the Glutamatergic System in Rat Hippocampus.

Prenatal hypoxia is among leading causes of progressive brain pathologies in postnatal life. This study aimed to analyze the characteristics of the hippocampal glutamatergic system and behavior of rats in early (2 weeks), adult (3 months) and advanced (18 months) postnatal ontogenesis after exposure to prenatal severe hypoxia (PSH, 180 Torr, 5% O2, 3 h) during the critical period in the formation of the hippocampus (days 14-16 of gestation). We have shown an age-dependent progressive decrease in the hippocampal glutamate levels, a decrease of the neuronal cell number in the CA1 hippocampal region, as well as impairment of spatial long-term memory in the Morris water navigation task. The gradual decrease of glutamate was accompanied by decreased expression of the genes that mediate glutamate metabolism and recycling in the hippocampus. That deficiency apparently correlated with an increase of the metabotropic glutamate receptor type 1 (mGluR1) and synaptophysin expression. Generation of the lipid peroxidation products in the hippocampus of adult rats subjected to prenatal severe hypoxia (PSH rats) was not increased compared to the control animals when tested in a model of glutamate excitotoxicity induced by severe hypoxia. This demonstrates that excessive glutamate sensitivity in PSH rats does not compensate for glutamate deficiency. Our results show a significant contribution of the glutamate system dysfunction to age-associated decrease of this mediator, cognitive decline, and early neuronal loss in PSH rats.

Lymphopenia in primary Sjögren's syndrome is associated with premature aging of naïve CD4+ T cells.

OBJECTIVE: To investigate peripheral lymphopenia, a frequent finding in primary Sjögren's syndrome (pSS) associated with higher disease activity and increased mortality. METHODS: Prospective, cross-sectional study of consecutive patients with pSS (n = 66) and healthy controls (n = 181). Lymphocyte subsets were analysed by flow cytometry, naïve (CD45RA+) and memory (CD45RO+) CD4+ T cells were purified by MACS technology. In vitro proliferation and senescence-associated ß-galactosidase (SABG) were assessed by flow cytometry. Telomere length and TCR excision circles (TREC) were measured by real-time PCR. Telomerase activity was analysed according to the telomeric repeat amplification protocols (TRAP). RESULTS: In pSS, lymphopenia mainly affected naïve CD4+ T cells. We noted a lower frequency of proliferating naïve CD4+ T cells ex vivo and decreased homeostatic proliferation in response to IL-7 stimulation in vitro. Furthermore, naïve CD4+ T cells exhibited signs of immune cell aging including shortened telomeres, a reduction in IL-7R expression and accumulation of SABG. The senescent phenotype could be explained by telomerase insufficiency and drastically reduced levels of T-cell receptor excision circles (TRECs), indicating a history of extensive post-thymic cell division. TRECs correlated with the number of naïve CD4+ T cells linking the extend of earlier proliferation to the inability to sustain normal cell numbers. CONCLUSION: In pSS, evidence for increased proliferation of naïve CD4+ T cells earlier in life is associated with a senescent phenotype unable to sustain homeostasis. The lack of naïve CD4+ T cells forms the basis of lymphopenia frequently observed in pSS.