Mechanisms of vascular aging: new perspectives

Diabetic microvascular complications among adults with type 2 diabetes in Adama, central Ethiopia

Microvascular complications, affecting small blood vessels, can lead to serious conditions such as kidney failure, painful nerve damage, and vision loss. Early detection and effective treatment of these issues are vital for improving patient outcomes and reducing healthcare expenses. Thus, this study aimed to assess diabetic microvascular complications among adults with type 2 diabetes in Adama, central Ethiopia. An institutional-based cross-sectional study was conducted among 381 adult type 2 diabetes patients. A computer-generated simple random sampling method was used to select study participants. Data were collected using a structured data extraction checklist. The collected data were entered into Epi info version 7.2 and exported to SPSS version 27 for processing and analysis. Binary logistic regression was employed to model the association between diabetic microvascular complications and explanatory variables. An adjusted odds ratio (AOR) with a 95% confidence interval (CI) was used to estimate the strength of association, and statistical significance was proclaimed at a p-value < 0.05. The prevalence of diabetic microvascular complications was 21.8% (95% CI: 17.8-25.6) with diabetic neuropathy being the most common (16.8%), followed by diabetic retinopathy (4.2%), and diabetic nephropathy (2.9%). Poor glycemic control (AOR = 2.00, 95% CI: 1.01-3.98), and a history of hypertension (AOR = 2.36, 95% CI: 1.39-4.00) were positively associated with the development of diabetic microvascular complications. Conversely, being aged 41-60 years (AOR = 0.35, 95% CI: 0.18-0.68) was negatively associated with the development of these complications. About one in five patients developed at least one diabetic microvascular complication. Age, poor glycemic control, and a history of hypertension were associated with the development of these complications. Therefore, intervening to improve glycemic control and manage hypertension is crucial in preventing the onset of diabetic microvascular complications.

Aged Gut Microbiome Induces Metabolic Impairment and Hallmarks of Vascular and Intestinal Aging in Young Mice

Aging, an independent risk factor for cardiometabolic diseases, refers to a progressive deterioration in physiological function, characterized by 12 established hallmarks. Vascular aging is driven by endothelial dysfunction, telomere dysfunction, oxidative stress, and vascular inflammation. This study investigated whether aged gut microbiome promotes vascular aging and metabolic impairment. Fecal microbiome transfer (FMT) was conducted from aged (>75 weeks old) to young C57BL/6 mice (8 weeks old) for 6 weeks. Wire myography was used to evaluate endothelial function in aortas and mesenteric arteries. ROS levels were measured by dihydroethidium (DHE) staining and lucigenin-enhanced chemiluminescence. Vascular and intestinal telomere function, in terms of relative telomere length, telomerase reverse transcriptase expression and telomerase activity, were measured. Systemic inflammation, endotoxemia and intestinal integrity of mice were assessed. Gut microbiome profiles were studied by 16S rRNA sequencing. Some middle-aged mice (40-42 weeks old) were subjected to chronic metformin treatment and exercise training for 4 weeks to evaluate their anti-aging benefits. Six-week FMT impaired glucose homeostasis and caused vascular dysfunction in aortas and mesenteric arteries in young mice. FMT triggered vascular inflammation and oxidative stress, along with declined telomerase activity and shorter telomere length in aortas. Additionally, FMT impaired intestinal integrity, and triggered AMPK inactivation and telomere dysfunction in intestines, potentially attributed to the altered gut microbial profiles. Metformin treatment and moderate exercise improved integrity, AMPK activation and telomere function in mouse intestines. Our data highlight aged microbiome as a mechanism that accelerates intestinal and vascular aging, suggesting the gut-vascular connection as a potential intervention target against cardiovascular aging and complications.

The Implications of Aging on Vascular Health

Vascular aging encompasses structural and functional changes in the vasculature, significantly contributing to cardiovascular diseases, which are the leading cause of death globally. The incidence and prevalence of these diseases increase with age, with most morbidity and mortality attributed to myocardial infarction and stroke. Diagnosing and intervening in vascular aging while understanding the mechanisms behind age-induced vascular phenotypic and pathophysiological alterations offers the potential for delaying and preventing cardiovascular mortality in an aging population. This review delves into various aspects of vascular aging by examining age-related changes in arterial health at the cellular level, including endothelial dysfunction, cellular senescence, and vascular smooth muscle cell transdifferentiation, as well as at the structural level, including arterial stiffness and changes in wall thickness and diameter. We also explore aging-related changes in perivascular adipose tissue deposition, arterial collateralization, and calcification, providing insights into the physiological and pathological implications. Overall, aging induces phenotypic changes that augment the vascular system's susceptibility to disease, even in the absence of traditional risk factors, such as hypertension, diabetes, obesity, and smoking. Overall, age-related modifications in cellular phenotype and molecular homeostasis increase the vulnerability of the arterial vasculature to structural and functional alterations, thereby accelerating cardiovascular risk. Increasing our understanding of these modifications is crucial for success in delaying or preventing cardiovascular diseases. Non-invasive techniques, such as measuring carotid intima-media thickness, pulse wave velocity, and flow-mediated dilation, as well as detecting vascular calcifications, can be used for the early detection of vascular aging. Targeting specific pathological mechanisms, such as cellular senescence and enhancing angiogenesis, holds promise for innovative therapeutic approaches.

Graded Intensity Aerobic Exercise to Improve Cerebrovascular Function and Performance in Older Veterans: Protocol for a Randomized Controlled Trial

BACKGROUND

Growing health care challenges resulting from a rapidly expanding aging population necessitate examining effective rehabilitation techniques that mitigate age-related comorbidity and improve quality of life. To date, exercise is one of a few proven interventions known to attenuate age-related declines in cognitive and sensorimotor functions critical to sustained independence.

OBJECTIVE

This work aims to implement a multimodal imaging approach to better understand the mechanistic underpinnings of the beneficial exercise-induced adaptations to sedentary older adults' brains and behaviors. Due to the complex cerebral and vascular dynamics that encompass neuroplastic change with aging and exercise, we propose an imaging protocol that will model exercise-induced changes to cerebral perfusion, cerebral vascular reactivity (CVR), and cognitive and sensorimotor task-dependent functional magnetic resonance imaging (fMRI) after prescribed exercise.

METHODS

Sedentary older adults (aged 65-80 years) were randomly assigned to either a 12-week aerobic-based interval-based cycling intervention or a 12-week balance and stretching intervention. Assessments of cardiovascular fitness used the YMCA submaximal VO2 test, basal cerebral perfusion using arterial spin labeling (ASL), CVR using hypercapnic fMRI, and cortical activation using fMRI during verbal fluency and motor tapping tasks. A battery of cognitive-executive and motor function tasks outside the scanning environment will be performed before and after the interventions.

RESULTS

Our studies and others show that improved cardiovascular fitness in older adults results in improved outcomes related to physical and cognitive health as well as quality of life. A consistent but unexplained finding in many of these studies is a change in cortical activation patterns during task-based fMRI, which corresponds with improved task performance (cognitive-executive and motor). We hypothesize that the 12-week aerobic exercise intervention will increase basal perfusion and improve CVR through a greater magnitude of reactivity in brain areas susceptible to neural and vascular decline (inferior frontal and motor cortices) in previously sedentary older adults. To differentiate between neural and vascular adaptations in these regions, we will map changes in basal perfusion and CVR over the inferior frontal and the motor cortices-regions we have previously shown to be beneficially altered during fMRI BOLD (blood oxygen level dependent), such as verbal fluency and motor tapping, through improved cardiovascular fitness.

CONCLUSIONS

Exercise is one of the most impactful interventions for improving physical and cognitive health in aging. This study aims to better understand the mechanistic underpinnings of improved health and function of the cerebrovascular system. If our hypothesis of improved perfusion and cerebrovascular reactivity following a 12-week aerobic exercise intervention is supported, it would add critically important insights into the potential of exercise to improve brain health in aging and could inform exercise prescription for older adults at risk for neurodegenerative disease brought on by cerebrovascular dysfunction.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05932069; https://clinicaltrials.gov/study/NCT05932069.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/58316.

Medin Induces Pro-Inflammatory Activation of Human Brain Vascular Smooth Muscle Cells

Background

Medin is one of the most common amyloidogenic proteins and accumulates in the vasculature with aging. Vascular medin accumulation is associated with Alzheimer's disease, vascular dementia and aortic aneurysms. Medin impairs smooth muscle-dependent vasodilation in isolated human brain cerebral arteries. The role of medin in vascular smooth muscle (VSMC) activation is unknown. We aim to evaluate the effects of medin on human brain VSMC activation.

Methods

VSMCs were exposed to physiologic doses of medin (0.5, 1 and 5 µM) without or with small molecule nuclear factor-κB (NFκB) inhibitor RO106-9920 (10 µM) for 20 hours. Polymerase chain reaction, Western blot/enzyme-linked immunosorbent assay were used to quantify gene and protein expressions/secretions, respectively, of pro-inflammatory factors (interleukin (IL)-6, IL-8 and monocyte chemoattractant protein (MCP)-1) and structural and enzyme proteins associated with VSMC phenotypic transformation (smooth muscle actin alpha 2 (ACTA2), myosin heavy chain 11 (MYH11) and NADPH oxidase 4 (NOX4)).

Results

Medin exposure increased VSMC gene expression and protein secretion of IL-6, IL-8 and MCP-1 (protein secretion 46.0±12.8x, 20.2±4.1x and 8.7±3.1x, respectively, medin 5 µM versus vehicle, all p<0.05). There was no change in gene or protein expressions of ACTA2, MYH11 and NOX4. Co-treatment with RO106-9920 reduced medin-induced increases in IL-6 and IL-8 and a trend towards reduced MCP-1 secretion.

Conclusions

Medin induced pro-inflammatory activation of human brain VSMCs that is mediated, at least in part, by NFκB. Acute medin treatment did not alter structural proteins involved in VSMC phenotypic transformation. The findings support medin as a potential novel mediator of and therapeutic target for vascular aging pathology.

Bruton's tyrosine kinase inhibition ameliorated neuroinflammation during chronic white matter ischemia

Chronic cerebral hypoperfusion (CCH), a disease afflicting numerous individuals worldwide, is a primary cause of cognitive deficits, the pathogenesis of which remains poorly understood. Bruton's tyrosine kinase inhibition (BTKi) is considered a promising strategy to regulate inflammatory responses within the brain, a crucial process that is assumed to drive ischemic demyelination progression. However, the potential role of BTKi in CCH has not been investigated so far. In the present study, we elucidated potential therapeutic roles of BTK in both in vitro hypoxia and in vivo ischemic demyelination model. We found that cerebral hypoperfusion induced white matter injury, cognitive impairments, microglial BTK activation, along with a series of microglia responses associated with inflammation, oxidative stress, mitochondrial dysfunction, and ferroptosis. Tolebrutinib treatment suppressed both the activation of microglia and microglial BTK expression. Meanwhile, microglia-related inflammation and ferroptosis processes were attenuated evidently, contributing to lower levels of disease severity. Taken together, BTKi ameliorated white matter injury and cognitive impairments induced by CCH, possibly via skewing microglia polarization towards anti-inflammatory and homeostatic phenotypes, as well as decreasing microglial oxidative stress damage and ferroptosis, which exhibits promising therapeutic potential in chronic cerebral hypoperfusion-induced demyelination.

Changes in the Proteome of the Circle of Willis during Aging Reveal Signatures of Vascular Disease

Approximately 70% of all strokes occur in patients over 65 years old, and stroke increases the risk of developing dementia. The circle of Willis (CoW), the ring of arteries at the base of the brain, links the intracerebral arteries to one another to maintain adequate cerebral perfusion. The CoW proteome is affected in cerebrovascular and neurodegenerative diseases, but changes related to aging have not been described. Here, we report on a quantitative proteomics analysis comparing the CoW from five young (2-3-month-old) and five aged male (18-20-month-old) mice using gene ontology (GO) enrichment, ingenuity pathway analysis (IPA), and iPathwayGuide tools. This revealed 242 proteins that were significantly dysregulated with aging, among which 189 were upregulated and 53 downregulated. GO enrichment-based analysis identified blood coagulation as the top biological function that changed with age and integrin binding and extracellular matrix constituents as the top molecular functions. Consistent with these findings, iPathwayGuide-based impact analysis revealed associations between aging and the complement and coagulation, platelet activation, ECM-receptor interaction, and metabolic process pathways. Furthermore, IPA analysis revealed the enrichment of 97 canonical pathways that contribute to inflammatory responses, as well as 59 inflammation-associated upstream regulators including 39 transcription factors and 20 cytokines. Thus, aging-associated changes in the CoW proteome in male mice demonstrate increases in metabolic, thrombotic, and inflammatory processes.

Nanoparticle-based therapeutic strategies for mitochondrial dysfunction in cardiovascular disease

Although cardiovascular diseases (CVD) are the leading cause of global mortality, there is a lack of therapies that target and revert underlying pathological processes. Mitochondrial dysfunction is involved in the pathophysiology of CVD, and thus is a potential target for therapeutic development. To target the mitochondria and improve therapeutic efficacy, nanoparticle-based delivery systems have been proposed as promising strategies for the delivery of therapeutic agents to the mitochondria. This review will first discuss how mitochondrial dysfunction is related to the progression of several CVD and then delineate recent progress in mitochondrial targeting using nanoparticle-based delivery systems including peptide-based nanosystems, polymeric nanoparticles, liposomes, and lipid nanoparticles. In addition, we summarize the advantages of these nanocarriers and remaining challenges in targeting the mitochondria as a therapeutic strategy for CVD treatment.

Differential ischemic stroke risk linked to novel subtypes of type 2 diabetes: insights from a Mendelian randomization analysis

PURPOSE

This study employs a two-sample Mendelian randomization (MR) approach to investigate the variation in ischemic stroke risk across novel subtypes of adult-onset type 2 diabetes.

METHODS

Leveraging pooled genome-wide association study (GWAS) data from the Swedish ANDIS cohort, we explored the association of four newly identified type 2 diabetes subtypes-severe insulin-deficient diabetes (SIDD), severe insulin-resistant diabetes (SIRD), mild obesity-related diabetes (MOD), and mild age-related diabetes (MARD)-with ischemic stroke risk. The outcome data for ischemic stroke and its three subtypes (large artery, cardioembolic, and small vessel stroke) were sourced from the MEGASTROKE Consortium. Our analysis applied multiple MR methods, focusing on the inverse-variance weighted (IVW) technique, complemented by thorough sensitivity analyses to examine heterogeneity and potential horizontal pleiotropy.

RESULTS

Our findings reveal a significant causal relationship between the SIDD subtype and small vessel stroke (OR = 1.06, 95% CI: 1.01-1.11, p = 0.025), while no causal associations were observed for SIRD with any stroke subtype. MOD was causally linked to small vessel stroke (OR = 1.07, 95% CI: 1.02-1.12, p = 0.004) and large artery stroke (OR = 1.07, 95% CI: 1.01-1.13, p = 0.015). Similarly, MARD showed a causal relationship with small vessel stroke (OR = 1.09, 95% CI: 1.03-1.16, p = 0.006) and overall ischemic stroke risk (OR = 1.04, 95% CI: 1.01-1.08, p = 0.010).

CONCLUSIONS

Our study highlights distinct causal links between specific type 2 diabetes subtypes and ischemic stroke risks, emphasizing the importance of subtype-specific prevention and treatment strategies.

Potential use of antioxidants for the treatment of chronic inflammatory diseases

The excessive production of various reactive oxidant species over endogenous antioxidant defense mechanisms leads to the development of a state of oxidative stress, with serious biological consequences. The consequences of oxidative stress depend on the balance between the generation of reactive oxidant species and the antioxidant defense and include oxidative damage of biomolecules, disruption of signal transduction, mutation, and cell apoptosis. Accumulating evidence suggests that oxidative stress is involved in the physiopathology of various debilitating illnesses associated with chronic inflammation, including cardiovascular diseases, diabetes, cancer, or neurodegenerative processes, that need continuous pharmacological treatment. Oxidative stress and chronic inflammation are tightly linked pathophysiological processes, one of which can be simply promoted by another. Although, many antioxidant trials have been unsuccessful (some of the trials showed either no effect or even harmful effects) in human patients as a preventive or curative measure, targeting oxidative stress remains an interesting therapeutic approach for the development of new agents to design novel anti-inflammatory drugs with a reliable safety profile. In this regard, several natural antioxidant compounds were explored as potential therapeutic options for the treatment of chronic inflammatory diseases. Several metalloenzymes, such as superoxide dismutase, catalase, and glutathione peroxidase, are among the essential enzymes that maintain the low nanomolar physiological concentrations of superoxide (O2•-) and hydrogen peroxide (H2O2), the major redox signaling molecules, and thus play important roles in the alteration of the redox homeostasis. These enzymes have become a striking source of motivation to design catalytic drugs to enhance the action of these enzymes under pathological conditions related to chronic inflammation. This review is focused on several major representatives of natural and synthetic antioxidants as potential drug candidates for the treatment of chronic inflammatory diseases.

Mitochondrial Dysfunction: A Roadmap for Understanding and Tackling Cardiovascular Aging

Cardiovascular aging is a progressive remodeling process constituting a variety of cellular and molecular alterations that are closely linked to mitochondrial dysfunction. Therefore, gaining a deeper understanding of the changes in mitochondrial function during cardiovascular aging is crucial for preventing cardiovascular diseases. Cardiac aging is accompanied by fibrosis, cardiomyocyte hypertrophy, metabolic changes, and infiltration of immune cells, collectively contributing to the overall remodeling of the heart. Similarly, during vascular aging, there is a profound remodeling of blood vessel structure. These remodeling present damage to endothelial cells, increased vascular stiffness, impaired formation of new blood vessels (angiogenesis), the development of arteriosclerosis, and chronic vascular inflammation. This review underscores the role of mitochondrial dysfunction in cardiac aging, exploring its impact on fibrosis and myocardial alterations, metabolic remodeling, immune response remodeling, as well as in vascular aging in the heart. Additionally, we emphasize the significance of mitochondria-targeted therapies in preventing cardiovascular diseases in the elderly.

Decreased retinal capillary density as a beneficial response to 24-week high-speed circuit resistant training in healthy older adults

PURPOSE

To determine the changes in retinal microvascular density after a 24-week high-speed circuit resistance training program (HSCT) in healthy older adults.

METHODS

Thirty healthy older adults were recruited and randomly assigned to either a training group (HSCT) or a non-training (CON) group. Fifteen subjects (age 73.3 ± 7.76 yrs) in the HSCT group exercised three times per week on non-consecutive days for 24 weeks. Fifteen subjects in the CON group (age 72.2 ± 6.04 yrs) did not have formal physical training. Both eyes of each subject were imaged using optical coherence tomography angiography (OCTA) at baseline and at the 24-week follow-up. The vessel densities of the retinal vascular network (RVN), superficial vascular plexus (SVP), and deep vascular plexus (DVP) were measured.

RESULTS

There were no demographic differences between the study groups. There were significant decreases in the retinal vessel densities of RVN, SVP and DVP in the HSCT group (P < 0.05). However, there were no significant changes in all three vascular measurements in the CON group (P > 0.05), although the changes showed a decreasing trend. The decreased vessel densities were doubled in the HSCT group in comparison to the CON group. However, the differences between groups did not reach a significant level (P > 0.05).

CONCLUSIONS

This is the first study to reveal the decreased retinal vessel densities as a possible imaging marker for the beneficial effects of the 24-week HSCT program in older adults.

Advanced age and female sex protect cerebral arteries from mitochondrial depolarization and apoptosis during acute oxidative stress

Aging increases reactive oxygen species (ROS) which can impair vascular function and contribute to brain injury. However, aging can also promote resilience to acute oxidative stress. Therefore, we tested the hypothesis that advanced age protects smooth muscle cells (SMCs) and endothelial cells (ECs) of posterior cerebral arteries (PCAs; diameter, ∼80 μm) during exposure to H2O2. PCAs from young (4-6 months) and old (20-26 months) male and female C57BL/6 mice were isolated and pressurized (~70 mm Hg) to evaluate cell death, mitochondrial membrane potential (ΔΨm), ROS production, and [Ca2+]i in response to H2O2 (200 μM, 50 min). SMC death and ΔΨm depolarization were greater in PCAs from males vs. females. Aging increased ROS in PCAs from both sexes but increased SMC resilience to death only in males. Inhibiting TRPV4 channels with HC-067047 (1 μM) or Src kinases with SU6656 (10 μM) reduced Ca2+ entry and SMC death to H2O2 most effectively in PCAs from young males. Activating TRPV4 channels with GSK1016790A (50 nM) evoked greater Ca2+ influx in SMCs and ECs of PCAs from young vs. old mice but did not induce cell death. However, when combined with H2O2, TRPV4 activation exacerbated EC death. Activating Src kinases with spermidine (100 μM) increased Ca2+ influx in PCAs from males vs. females with minimal cell death. We conclude that in males, chronic oxidative stress during aging increases the resilience of cerebral arteries, which contrasts with inherent protection in females. Findings implicate TRP channels and Src kinases as targets to limit vascular damage to acute oxidative injury.

Hydrogel-based cardiac repair and regeneration function in the treatment of myocardial infarction

A life-threatening illness that poses a serious threat to human health is myocardial infarction. It may result in a significant number of myocardial cells dying, dilated left ventricles, dysfunctional heart function, and ultimately cardiac failure. Based on the development of emerging biomaterials and the lack of clinical treatment methods and cardiac donors for myocardial infarction, hydrogels with good compatibility have been gradually applied to the treatment of myocardial infarction. Specifically, based on the three processes of pathophysiology of myocardial infarction, we summarized various types of hydrogels designed for myocardial tissue engineering in recent years, including natural hydrogels, intelligent hydrogels, growth factors, stem cells, and microRNA-loaded hydrogels. In addition, we also describe the heart patch and preparation techniques that promote the repair of MI heart function. Although most of these hydrogels are still in the preclinical research stage and lack of clinical trials, they have great potential for further application in the future. It is expected that this review will improve our knowledge of and offer fresh approaches to treating myocardial infarction.

Dysfunctional mitochondria elicit bioenergetic decline in the aged heart

Aging represents a complex biological progression affecting the entire body, marked by a gradual decline in tissue function, rendering organs more susceptible to stress and diseases. The human heart holds significant importance in this context, as its aging process poses life-threatening risks. It entails macroscopic morphological shifts and biochemical changes that collectively contribute to diminished cardiac function. Among the numerous pivotal factors in aging, mitochondria play a critical role, intersecting with various molecular pathways and housing several aging-related agents. In this comprehensive review, we provide an updated overview of the functional role of mitochondria in cardiac aging.

Cortical microvascular raspberries and ageing: an independent but not exclusive relationship

INTRODUCTION

Raspberries are cerebral microvascular formations of unknown origin, defined as three or more transversally sectioned vascular lumina surrounded by a common perivascular space. We have previously demonstrated an increased raspberry density in the cortex of patients with vascular dementia and cerebral atherosclerosis, while studies by other authors on overlapping and synonymously defined vascular entities mainly associate them with advancing age. The aim of the present study was to examine the relationship between raspberries and age in a large study sample while including multiple potential confounding factors in the analysis.

MATERIALS AND METHODS

Our study sample consisted of 263 individuals aged 20-97 years who had undergone a clinical autopsy including a neuropathological examination. The cortical raspberry density had either been quantified as part of a previous study or was examined de novo in a uniform manner on haematoxylin- and eosin-stained tissue sections from the frontal lobe. The medical records and autopsy reports were assessed regarding neurodegeneration, cerebral infarcts, cerebral atherosclerosis and small vessel disease, cardiac hypertrophy, nephrosclerosis, hypertension, and diabetes mellitus. With the patients grouped according to 10-year age interval, non-parametric tests (the Kruskal-Wallis test, followed by pairwise testing with Bonferroni-corrected P values) and multiple linear regression models (not corrected for multiple tests) were performed.

RESULTS

The average raspberry density increased with advancing age. The non-parametric tests demonstrated statistically significant differences in raspberry density when comparing the groups aged 60-99 years and 70-99 years to those aged 20-29 years (P < 0.012) and 30-59 years (P < 0.011), respectively. The multiple linear regression models demonstrated positive associations with age interval (P < 0.001), cerebral atherosclerosis (P = 0.024), cardiac hypertrophy (P = 0.021), hypertension subgrouped for organ damage (P = 0.006), and female sex (P = 0.004), and a tendency towards a negative association with Alzheimer's disease neuropathologic change (P = 0.048).

CONCLUSION

The raspberry density of the frontal cortex increases with advancing age, but our results also indicate associations with acquired pathologies. Awareness of the biological and pathological context where raspberries occur can guide further research on their origin.

Transcriptomic analyses reveal proinflammatory activation of human brain microvascular endothelial cells by aging-associated peptide medin and reversal by nanoliposomes

Medin is a common vascular amyloidogenic peptide recently implicated in Alzheimer's disease (AD) and vascular dementia and its pathology remains unknown. We aim to identify changes in transcriptomic profiles and pathways in human brain microvascular endothelial cells (HBMVECs) exposed to medin, compare that to exposure to β-amyloid (Aβ) and evaluate protection by monosialoganglioside-containing nanoliposomes (NL). HBMVECs were exposed for 20 h to medin (5 µM) without or with Aβ(1-42) (2 µM) or NL (300 µg/mL), and RNA-seq with signaling pathway analyses were performed. Separately, reverse transcription polymerase chain reaction of select identified genes was done in HBMVECs treated with medin (5 µM) without or with NFκB inhibitor RO106-9920 (10 µM) or NL (300 µg/mL). Medin caused upregulation of pro-inflammatory genes that was not aggravated by Aβ42 co-treatment but reversed by NL. Pathway analysis on differentially expressed genes revealed multiple pro-inflammatory signaling pathways, such as the tumor necrosis factor (TNF) and the nuclear factor-κB (NFkB) signaling pathways, were affected specifically by medin treatment. RO106-9920 and NL reduced medin-induced pro-inflammatory activation. Medin induced endothelial cell pro-inflammatory signaling in part via NFκB that was reversed by NL. This could have potential implications in the pathogenesis and treatment of vascular aging, AD and vascular dementia.

Role of diet and exercise in aging, Alzheimer's disease, and other chronic diseases

Alzheimer's disease (AD) is a progressive neurodegenerative disease, characterized by memory loss and multiple cognitive impairments. Genetic mutations cause a small proportion (1-2%) of early-onset AD, with mutations in amyloid precursor protein (APP), presenilin 1 (PS1) and presenilin 2 (PS2). Major contributing factors of late-onset AD are ApoE4 genotype, traumatic brain injury, diabetes, obesity, hypertension, cardiovascular conditions, in addition to lifestyle factors, such as unhealthy diet and lack of physical exercise. Disease progression can be delayed and/or prevented to a greater extent by adopting healthy lifestyle with balanced and antioxidant enriched diet and daily exercise. The interaction and interplay of diet, exercise, age, and pharmacological interventions holds a crucial role in the progression, pathogenesis and management of AD and its comorbidities, including diabetes, obesity, hypertension and cardiovascular conditions. Antioxidant enriched diet contributes to brain health, glucose control, weight management, and cardiovascular well-being. Regular exercise removes toxins including free radicals and enhances insulin sensitivity, and supports cardiovascular function. In the current article, we discussed, the role of diet, and exercise in aging, AD and other conditions including diabetes, obesity, hypertension, cardiovascular conditions. This article also highlights the impact of medication, socioeconomic and lifestyle factors, and pharmacological interventions. These aspects were discussed in different races and ethnic groups in Texas, and the US.

Comparison of treatment outcomes and complications of coil embolization in elderly and very elderly patients with cerebral aneurysms: a propensity score matching analysis

PURPOSE

This single center study aims to compare the treatment outcomes and procedure-related complications of coil embolization in elderly patients (60-79 years) and very elderly patients (aged 80 years or older) with cerebral aneurysms.

METHODS

Data was collected from 504 elderly patients aged 60 years or older who underwent coil embolization for intracranial aneurysms from 2018 to 2021. The study evaluated patient-related and anatomical factors and assessed various outcomes, comparing results between groups using statistical analysis and propensity score matching.

RESULTS

A total of 503 cerebral aneurysms were analyzed from individuals aged 60-79 years (n = 472) and those aged 80 years or older (n = 31). The majority of the aneurysms were unruptured with an average size of 3.5 mm in height and 3.4 mm in width. The patients were compared using 1:1 propensity score matching, and no significant differences were found in factors other than age and aortic elongation. Logistic analysis revealed that being over 80 years old and having a severe aortic arch elongation were identified as risk factors for procedure-related events in both total and unruptured cases.

CONCLUSIONS

The study compared coil embolization treatment for cerebral aneurysms in patients aged 60-79 and over 80, finding no significant difference in treatment outcomes except for procedure-related events. Procedure-related events were associated with severe aortic arch elongation and being over 80 years old. Coil embolization can be considered safe and effective for patients over 80, but further trials are needed for accurate conclusions.

Impaired cerebrovascular reactivity correlates with reduced retinal vessel density in patients with carotid artery stenosis: Cross-sectional, single center study

BACKGROUND

The cerebral and retinal circulation systems are developmentally, anatomically, and physiologically interconnected. Thus, we hypothesized that hypoperfusion due to atherosclerotic stenosis of the internal carotid artery (ICA) can result in disturbances of both cerebral and retinal microcirculations. We aimed to characterize parameters indicating cerebrovascular reactivity (CVR) and retinal microvascular density in patients with ICA stenosis, and assess if there is correlation between them.

METHODS

In this cross-sectional study the middle cerebral artery (MCA) blood flow velocity was measured by transcranial Doppler (TCD) and, simultaneously, continuous non-invasive arterial blood pressure measurement was performed on the radial artery by applanation tonometry. CVR was assessed based on the response to the common carotid artery compression (CCC) test. The transient hyperemic response ratio (THRR) and cerebral arterial resistance transient hyperemic response ratio (CAR-THRR) were calculated. Optical coherence tomography angiography (OCTA) was used to determine vessel density (VD) on the papilla whole image for all (VDP-WIall) and for small vessels (VDP-WIsmall). The same was done in the peripapillary region: all (VDPPall), and small (VDPPsmall) vessels. The VD of superficial (VDMspf) and deep (VDMdeep) macula was also determined. Significance was accepted when p<0.05.

RESULTS

Twenty-four ICA stenotic patients were evaluated. Both CVR and retinal VD were characterized. There was a significant, negative correlation between CAR-THRR (median = -0.40) and VDPPsmall vessels (median = 52%), as well as between VDPPall vessels (median = 58%), and similar correlation between CAR-THRR and VDP-WIsmall (median = 49.5%) and between VDP-WIall (median = 55%).

CONCLUSION

The significant correlation between impaired cerebrovascular reactivity and retinal vessel density in patients with ICA stenosis suggests a common mechanism of action. We propose that the combined use of these diagnostic tools (TCD and OCTA) helps to better identify patients with increased ischemic or other cerebrovascular risks.

Vascular Aging: Assessment and Intervention

Vascular aging represents a collection of structural and functional changes in a blood vessel with advancing age, including increased stiffness, vascular wall remodeling, loss of angiogenic ability, and endothelium-dependent vasodilation dysfunction. These age-related alterations may occur earlier in those who are at risk for or have cardiovascular diseases, therefore, are defined as early or premature vascular aging. Vascular aging contributes independently to cardio-cerebral vascular diseases (CCVDs). Thus, early diagnosis and interventions targeting vascular aging are of paramount importance in the delay or prevention of CCVDs. Here, we review the direct assessment of vascular aging by examining parameters that reflect changes in structure, function, or their compliance with age including arterial wall thickness and lumen diameter, endothelium-dependent vasodilation, arterial stiffness as well as indirect assessment through pathological studies of biomarkers including endothelial progenitor cell, lymphocytic telomeres, advanced glycation end-products, and C-reactive protein. Further, we evaluate how different types of interventions including lifestyle mediation, such as caloric restriction and salt intake, and treatments for hypertension, diabetes, and hyperlipidemia affect age-related vascular changes. As a single parameter or intervention targets only a certain vascular physiological change, it is recommended to use multiple parameters to evaluate and design intervention approaches accordingly to prevent systemic vascular aging in clinical practices or population-based studies.

Associations among multidomain lifestyles, chronic diseases, and dementia in older adults: a cross-sectional analysis of a cohort study

Background

Unhealthy lifestyles and chronic diseases are commonly seen and treatable factors in older adults and are both associated with dementia. However, the synergistic effect of the interaction of lifestyles and chronic diseases on dementia is unknown.

Methods

We determined independent associations of multidomain lifestyles and chronic diseases (cerebrovascular disease, diabetes, and hypertension) with dementia and examined their synergistic impact on dementia among older adults. The data were drawn from the Hubei Memory and Aging Cohort Study. We created a summary score of six factors for multidomain lifestyles. Dementia was diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders IV. Logistic regression and multiple correspondence analyses were used to explore the relationships among multidomain lifestyles, chronic diseases, and dementia. A sensitivity analysis was performed to minimize the interference of reverse causality and potential confounders.

Results

Independent associations with dementia were found in unhealthy (OR = 1.90, 95% CI: 1.38-2.61) and intermediate healthy lifestyles (OR, 3.29, 2.32-4.68), hypertension (OR, 1.21, 1.01-1.46), diabetes (OR, 1.30, 1.04-1.63), and cerebrovascular disease (OR, 1.39, 1.12-1.72). Interactions of diabetes (p = 0.004), hypertension (p = 0.004), and lifestyles were significant, suggesting a combined impact on dementia. Sensitivity analysis supported the strong association among multidomain lifestyles, chronic diseases, and dementia prevalence.

Conclusion

An unhealthy lifestyle was associated with a higher prevalence of dementia, regardless of whether the participants had chronic diseases; however, this association was stronger in individuals with chronic diseases. Multidomain lifestyles and chronic diseases may have an enhanced impact on dementia.

Therapeutic potential of nitric oxide in vascular aging due to the promotion of angiogenesis

The decrease in angiogenesis that occurs with aging significantly contributes to the higher incidence and mortality of cardiovascular diseases among the elderly. This decline in angiogenesis becomes more pronounced with increasing age and is closely linked to abnormal function and senescence of endothelial cells. Enhancing angiogenesis in aging and targeting senescent endothelial cells have gained considerable attention. Nitric oxide (NO) has been thoroughly investigated for its function in regulating angiogenesis and is an important factor that can counteract endothelial cell senescence. This review summarizes the mechanisms of reduced angiogenesis during aging and therapeutic strategies targeting senescent cells. We also discuss the potential of combining the current approaches with NO in promoting angiogenesis in aging vessels.

Cold exposure protects against medial arterial calcification development via autophagy

Medial arterial calcification (MAC), a systemic vascular disease different from atherosclerosis, is associated with an increased incidence of cardiovascular events. Several studies have demonstrated that ambient temperature is one of the most important factors affecting cardiovascular events. However, there has been limited research on the effect of different ambient temperatures on MAC. In the present study, we showed that cold temperature exposure (CT) in mice slowed down the formation of vitamin D (VD)-induced vascular calcification compared with room temperature exposure (RT). To investigate the mechanism involved, we isolated plasma-derived exosomes from mice subjected to CT or RT for 30 days (CT-Exo or RT-Exo, respectively). Compared with RT-Exo, CT-Exo remarkably alleviated the calcification/senescence formation of vascular smooth muscle cells (VSMCs) and promoted autophagy by activating the phosphorylation of AMP-activated protein kinase (p-AMPK) and inhibiting phosphorylation of mammalian target of rapamycin (p-mTOR). At the same time, CT-Exo promoted autophagy in β-glycerophosphate (β-GP)-induced VSMCs. The number of autophagosomes and the expression of autophagy-related proteins ATG5 and LC3B increased, while the expression of p62 decreased. Based on a microRNA chip microarray assay and real-time polymerase chain reaction, miR-320a-3p was highly enriched in CT-Exo as well as thoracic aortic vessels in CT mice. miR-320a-3p downregulation in CT-Exo using AntagomiR-320a-3p inhibited autophagy and blunted its anti-calcification protective effect on VSMCs. Moreover, we identified that programmed cell death 4 (PDCD4) is a target of miR-320a-3p, and silencing PDCD4 increased autophagy and decreased calcification in VSMCs. Treatment with CT-Exo alleviated the formation of MAC in VD-treated mice, while these effects were partially reversed by GW4869. Furthermore, the anti-arterial calcification protective effects of CT-Exo were largely abolished by AntagomiR-320a-3p in VD-induced mice. In summary, we have highlighted that prolonged cold may be a good way to reduce the incidence of MAC. Specifically, miR-320a-3p from CT-Exo could protect against the initiation and progression of MAC via the AMPK/mTOR autophagy pathway.

Chronic cerebral hypoperfusion: a critical feature in unravelling the etiology of vascular cognitive impairment

Vascular cognitive impairment (VCI) describes a wide spectrum of cognitive deficits related to cerebrovascular diseases. Although the loss of blood flow to cortical regions critically involved in cognitive processes must feature as the main driver of VCI, the underlying mechanisms and interactions with related disease processes remain to be fully elucidated. Recent clinical studies of cerebral blood flow measurements have supported the role of chronic cerebral hypoperfusion (CCH) as a major driver of the vascular pathology and clinical manifestations of VCI. Here we review the pathophysiological mechanisms as well as neuropathological changes of CCH. Potential interventional strategies for VCI are also reviewed. A deeper understanding of how CCH can lead to accumulation of VCI-associated pathology could potentially pave the way for early detection and development of disease-modifying therapies, thus allowing preventive interventions instead of symptomatic treatments.

Accelerated ageing and coronary microvascular dysfunction in chronic heart failure in Tgαq*44 mice

Age represents a major risk factor in heart failure (HF). However, the mechanisms linking ageing and HF are not clear. We aimed to identify the functional, morphological and transcriptomic changes that could be attributed to cardiac ageing in a model of slowly progressing HF in Tgαq*44 mice in reference to the cardiac ageing process in FVB mice. In FVB mice, ageing resulted in the impairment of diastolic cardiac function and in basal coronary flow (CF), perivascular and interstitial fibrosis without changes in the cardiac activity of angiotensin-converting enzyme (ACE) or aldosterone plasma concentration. In Tgαq*44 mice, HF progression was featured by the impairment of systolic and diastolic cardiac function and in basal CF that was associated with a distinct rearrangement of the capillary architecture, pronounced perivascular and interstitial fibrosis, progressive activation of cardiac ACE and systemic angiotensin-aldosterone-dependent pathways. Interestingly, cardiac ageing genes and processes were represented in Tgαq*44 mice not only in late but also in early phases of HF, as evidenced by cardiac transcriptome analysis. Thirty-four genes and 8 biological processes, identified as being ageing related, occurred early and persisted along HF progression in Tgαq*44 mice and were mostly associated with extracellular matrix remodelling and fibrosis compatible with perivascular fibrosis resulting in coronary microvascular dysfunction (CMD) in Tgαq*44 mice. In conclusion, accelerated and persistent cardiac ageing contributes to the pathophysiology of chronic HF in Tgαq*44 mice. In particular, prominent perivascular fibrosis of microcirculation resulting in CMD represents an accelerated cardiac ageing phenotype that requires targeted treatment in chronic HF.

SIRT1 Signaling Is Involved in the Vascular Improvement Induced by Moringa Oleifera Seeds during Aging

Vascular aging is linked to reduce NO bioavailability, endothelial dysfunction, oxidative stress, and inflammation. We previously showed that a 4-week treatment of middle-aged Wistar rats (MAWRs, 46 weeks old) with Moringa oleifera seed powder (MOI, 750 mg/kg/day) improved vascular function. Here, we investigated the involvement of SIRT1 in MOI-induced vascular improvement. MAWRs were treated with a standard or MOI-containing diet. Young rats (YWR, 16 weeks old) were the controls and received a standard diet. The hearts and aortas were harvested to evaluate SIRT1 and FOXO1 expression via Western blot and/or immunostaining, SIRT1 activity via a fluorometric assay, and oxidative stress using the DHE fluorescent probe. In the hearts and aortas, SIRT1 expression, reduced in MAWRs compared to YWRs, was enhanced in MOI MAWRs. In the hearts, SIRT1 activity did not differ between YWRs and MAWRs, whereas it was increased in MOI MAWRs compared with them. In the aortas, SIRT1 activity decreased in MAWRs, and it was similar in the MOI MAWRs and YWRs. FOXO1 expression increased in the nuclei of MAWR aortas compared to YWR and was reversed in MOI MAWRs. Interestingly, MOI treatment normalized oxidative stress enhanced in MAWRs, in both the heart and aorta. These results demonstrate the protective role of MOI against cardiovascular dysfunction due to aging via enhanced SIRT1 function and subsequently reduced oxidative stress.

Advancing age increases the size and severity of spontaneous atheromas in mouse models of atherosclerosis

Using multiple mouse models, we explored the impact of aging on the size and severity of atherosclerotic lesions. In young, middle-aged and old apolipoprotein E knockout mice (ApoE^-/-) fed an atherogenic diet (AD) for 3-8 weeks, plaque/atheroma formation in the descending aorta and aortic root, and atheroma development in the carotid in response to partial carotid ligation (PCL) were assessed. Total and LDL cholesterol, and triglycerides were higher in old compared to both other age groups, regardless of AD duration. Aortic plaque burden increased with AD duration in all ages. The size and plaque morphology grade of aortic root atheromas was higher with age; however, there was no effect of age on the size or severity of carotid atheromas after PCL. We additionally induced hyperlipidemia in young and old C57BL/6 mice by adeno-associated virus mediated upregulation of LDL receptor regulator, Pcsk9, and 5 weeks of AD. Despite lower cholesterol in old compared to young Pcsk9 mice, there was a greater size and severity of aortic root atheromas in old mice. However, like the ApoE^-/- mice, there was no effect of age on size or severity of PCL-induced carotid artery atheromas in Pcsk9 mice. Together, these results suggest that aging increases the size and severity of spontaneous aortic atheromas.

Accelerated Vascular Aging in Chronic Kidney Disease: The Potential for Novel Therapies

The pathophysiology of vascular disease is linked to accelerated biological aging and a combination of genetic, lifestyle, biological, and environmental risk factors. Within the scenario of uncontrolled artery wall aging processes, CKD (chronic kidney disease) stands out as a valid model for detailed structural, functional, and molecular studies of this process. The cardiorenal syndrome relates to the detrimental bidirectional interplay between the kidney and the cardiovascular system. In addition to established risk factors, this group of patients is subjected to a plethora of other emerging vascular risk factors, such as inflammation, oxidative stress, mitochondrial dysfunction, vitamin K deficiency, cellular senescence, somatic mutations, epigenetic modifications, and increased apoptosis. A better understanding of the molecular mechanisms through which the uremic milieu triggers and maintains early vascular aging processes, has provided important new clues on inflammatory pathways and emerging risk factors alike, and to the altered behavior of cells in the arterial wall. Advances in the understanding of the biology of uremic early vascular aging opens avenues to novel pharmacological and nutritional therapeutic interventions. Such strategies hold promise to improve future prevention and treatment of early vascular aging not only in CKD but also in the elderly general population.

Exercise protects vascular function by countering senescent cells in older adults

Blood vessels are key conduits for the transport of blood and circulating factors. Abnormalities in blood vessels promote cardiovascular disease (CVD), which has become the most common disease as human lifespans extend. Aging itself is not pathogenic; however, the decline of physiological and biological function owing to aging has been linked to CVD. Although aging is a complex phenomenon that has not been comprehensively investigated, there is accumulating evidence that cellular senescence aggravates various pathological changes associated with aging. Emerging evidence shows that approaches that suppress or eliminate cellular senescence preserve vascular function in aging-related CVD. However, most pharmacological therapies for treating age-related CVD are inefficient. Therefore, effective approaches to treat CVD are urgently required. The benefits of exercise for the cardiovascular system have been well documented in basic research and clinical studies; however, the mechanisms and optimal frequency of exercise for promoting cardiovascular health remain unknown. Accordingly, in this review, we have discussed the changes in senescent endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) that occur in the progress of CVD and the roles of physical activity in CVD prevention and treatment.

Mechanistic and therapeutic role of Drp1 in the pathogenesis of stroke

Stroke had emerged as one of the leading causes of death and long-term disability across the globe. Emerging evidence suggests a significant increase in the incidence of stroke with age, which is further expected to increase dramatically owing to an ever-expanding elderly population. The current situation imposes a significant burden on the healthcare system and requires a deeper understanding of the underlying mechanisms and development of novel interventions. It is well established that mitochondrial dysfunction plays a pivotal role in the onset of stroke. Dynamin-related protein 1 (Drp1), is a key regulator of mitochondria fission, and plays a crucial role during the pathogenesis of stroke. Drp1 protein levels significantly increase after stroke potentially in a p38 mitogen-activated protein kinases (MAPK) dependent manner. Protein phosphatase 2A (PP2A) facilitate mitochondrial fission and cell death by dephosphorylating the mitochondrial fission enzyme Drp1 at the inhibitory phosphorylation site serine 637. Outer mitochondrial membrane A-Kinase Anchoring Proteins 1 (AKAP 1) and protein kinase A complex (PKA) complex inhibits Drp1-dependent mitochondrial fission by phosphorylating serine 637. Drp1 activation promotes the release of cytochrome C from mitochondria and therefore leads to apoptosis. In addition, Drp1 activation inhibits mitochondrial glutathione dependent free radical scavenging, which further enhances the ROS level and exacerbate mitochondrial dysfunction. Drp1 translocate p53 to mitochondrial membrane and leads to mitochondria-related necrosis. The current review article discusses the possible mechanistic pathways by which Drp1 can influence the pathogenesis of stroke. Besides, it will describe various inhibitors for Drp1 and their potential role as therapeutics for stroke in the future.

Efficient Neural Differentiation of Mouse Embryonic Stem Cells by Mastic Gum

Purpose: Promoting neurogenesis is a promising strategy to treat neurodegenerative disorders. In the present study, we aimed to evaluate the effect of mastic gum resin from the Pistacia lentiscus var. Chia (Anacardiaceae family) in proliferation capacity and differentiation of embryonic mesenchymal stem cells into a neural lineage. Methods: For this purpose, mastic gum was applied as a neural inducer for stem cell differentiation into the neuronal lineage. Following treatment of embryonic stem cells (ESCs) with mastic gum, verification differentiation of the ESCs into the neuronal lineage, gene expression analysis, and immunocytochemistry staining approach were performed. Results: Gene expression analysis demonstrated that mastic gum increased the expression level of neuron markers in the ESCs-derived neuron-like cells. Moreover, our immunocytochemistry staining results of two important neural stem cell markers, including Nestin and microtubule-associated protein-2 (Map2) expression confirmed that mastic gum has the potential to promote neuronal differentiation in ESCs. Conclusion: In summary, the use of mastic gum to stimulate the differentiation of ESCs into a neural lineage can be considered as a good candidate in stem cell therapy.

Cell non-autonomous regulation of cerebrovascular aging processes by the somatotropic axis

Age-related cerebrovascular pathologies, ranging from cerebromicrovascular functional and structural alterations to large vessel atherosclerosis, promote the genesis of vascular cognitive impairment and dementia (VCID) and exacerbate Alzheimer's disease. Recent advances in geroscience, including results from studies on heterochronic parabiosis models, reinforce the hypothesis that cell non-autonomous mechanisms play a key role in regulating cerebrovascular aging processes. Growth hormone (GH) and insulin-like growth factor 1 (IGF-1) exert multifaceted vasoprotective effects and production of both hormones is significantly reduced in aging. This brief overview focuses on the role of age-related GH/IGF-1 deficiency in the development of cerebrovascular pathologies and VCID. It explores the mechanistic links among alterations in the somatotropic axis, specific macrovascular and microvascular pathologies (including capillary rarefaction, microhemorrhages, impaired endothelial regulation of cerebral blood flow, disruption of the blood brain barrier, decreased neurovascular coupling, and atherogenesis) and cognitive impairment. Improved understanding of cell non-autonomous mechanisms of vascular aging is crucial to identify targets for intervention to promote cerebrovascular and brain health in older adults.

Genome-wide association study for vascular aging highlights pathways shared with cardiovascular traits in Koreans

Vascular aging plays a pivotal role in the morbidity and mortality of older people. Reactive hyperemia index (RHI) detected by pulse amplitude tonometry (PAT) is a non-invasive measure of vascular endothelial function and aging-induced pathogenesis of both microvascular and macrovascular diseases. We conducted a genome-wide association study (GWAS) to comprehensively identify germline genetic variants associated with vascular aging in a Korean population, which revealed 60 suggestive genes underlying angiogenesis, inflammatory response in blood vessels, and cardiovascular diseases. Subsequently, we show that putative protective alleles were significantly enriched in an independent population with decelerated vascular aging phenotypes. Finally, we show the differential mRNA expression levels of putative causal genes in aging human primary endothelial cells via quantitative real-time polymerase chain reaction (PCR). These results highlight the potential contribution of genetic variants in the etiology of vascular aging and may suggest the link between vascular aging and cardiovascular traits.

The Aging Heart: A Molecular and Clinical Challenge

Aging is associated with an increasing burden of morbidity, especially for cardiovascular diseases (CVDs). General cardiovascular risk factors, ischemic heart diseases, heart failure, arrhythmias, and cardiomyopathies present a significant prevalence in older people, and are characterized by peculiar clinical manifestations that have distinct features compared with the same conditions in a younger population. Remarkably, the aging heart phenotype in both healthy individuals and patients with CVD reflects modifications at the cellular level. An improvement in the knowledge of the physiological and pathological molecular mechanisms underlying cardiac aging could improve clinical management of older patients and offer new therapeutic targets.

Antioxidant Intervention to Improve Cognition in the Aging Brain: The Example of Hydroxytyrosol and Resveratrol

Both physiological and pathological aging processes induce brain alterations especially affecting the speed of processing, working memory, conceptual reasoning and executive functions. Many therapeutic approaches to reduce the impact of brain aging on cognitive functioning have been tested; unfortunately, there are no satisfactory results as a single therapy. As aging is partly contributed by free radical reactions, it has been proposed that exogenous antioxidants could have a positive impact on both aging and its associated manifestations. The aim of this report is to provide a summary and a subsequent review of the literature evidence on the role of antioxidants in preventing and improving cognition in the aging brain. Manipulation of endogenous cellular defense mechanisms through nutritional antioxidants or pharmacological compounds represents an innovative approach to therapeutic intervention in diseases causing brain tissue damage, such as neurodegeneration. Coherently with this notion, antioxidants, especially those derived from the Mediterranean diet such as hydroxytyrosol and resveratrol, seem to be able to delay and modulate the cognitive brain aging processes and decrease the occurrence of its effects on the brain. The potential preventive activity of antioxidants should be evaluated in long-term exposure clinical trials, using preparations with high bioavailability, able to bypass the blood-brain barrier limitation, and that are well standardized.

Angiogenic ability of human endothelial cells was decreased following senescence induction with hydrogen peroxide: possible role of vegfr-2/akt-1 signaling pathway

Background

Many attempts are used to discover mechanisms driving impaired angiogenesis in age-related diseases. Angiogenesis is highly regulated by different signaling pathways. Here, we investigated the angiogenesis potential of human endothelial cells (ECs) upon exposure to hydrogen peroxide (H2O2), a cellular senescent factor.

Results

Data showed that the wound healing rate of HUVECs decreased upon incubation with H2O2 (P < 0.05). LOX activity and NO production were decreased in H2O2 treated cells (P < 0.05). Expression of miR-126 and VEGFR-2 up-regulated, while expression of miR-373 and HSP-70 up = regulated in H2O2 -induced cells (P < 0.05). In addition, we found that protein levels of p-Akt-1, VCAM-1, MMP-9, and IL-6 decreased in treated cells (P < 0.05).

Conclusions

Our data showed that H2O2 reduced the angiogenic response of HUVECs in vitro, which may be due to impairment of the VEGFR-2 signaling pathway.

miR-195-3p/BDNF axis regulates hypoxic injury by targeting P-ERK1/2 expression

OBJECTIVES

Coronary heart disease (CHD) is the most common heart disease and the leading cause of cardiovascular deaths worldwide. Decreased endothelial cell (EC) proliferation, increased apoptosis, inflammation, and vascular dysfunction are considered vital factors in CHD. In this study, we aimed to determine the expression and role of microRNA-195-3p and brain-derived neurotrophic factor (BDNF) in hypoxic-treated human umbilical vein endothelial cells (HUVECs).

MEASURES

We induced hypoxia in HUVECs using the "anaerobic tank method."

RESULTS

We found that the levels of microRNA-195-3p and BDNF were upregulated and apoptosis was increased. Furthermore, we found that BDNF/P-ERK1/2 regulated the expression of the mitochondrial apoptosis pathway proteins Bcl-2/BAX, which was downregulated under hypoxic conditions. Finally, the microRNA-195-3p inhibitor downregulated BDNF and P-ERK1/2, upregulated the Bcl-2/BAX axis, and partially reversed the effects of hypoxic-induced injury in HUVECs.

CONCLUSIONS

Therapeutic intervention using the microRNA-195-3p/BDNF/P-ERK1/2/Bcl-2/BAX axis could maintain EC function under hypoxic conditions, improve cell activity, and serve as a new treatment strategy for CHDs.

Vascular Aging and Damage in Patients with Iron Metabolism Disorders

Vascular aging is a physiological, multifactorial process that involves every type of vessel, from large arteries to microcirculation. This manifests itself as impaired vasomotor function, altered secretory phenotype, deteriorated intercellular transport function, structural remodeling, and aggravated barrier function between the blood and the vascular smooth muscle layer. Iron disorders, particularly iron overload, may lead to oxidative stress and, among other effects, vascular aging. The elevated transferrin saturation and serum iron levels observed in iron overload lead to the formation of a non-transferrin-bound iron (NTBI) fraction with high pro-oxidant activity. NTBI can induce the production of reactive oxygen species (ROS), which induce lipid peroxidation and mediate iron-related damage as the elements of oxidative stress in many tissues, including heart and vessels' mitochondria. However, the available data make it difficult to precisely determine the impact of iron metabolism disorders on vascular aging; therefore, the relationship requires further investigation. Our study aims to present the current state of knowledge on vascular aging in patients with deteriorated iron metabolism.

Alpha-Lipoic Acid Supplementation Restores Early Age-Related Sensory and Endothelial Dysfunction in the Skin

Many changes characterize skin aging, and the resulting dysfunctions still constitute a real challenge for our society. The aim of this study was to compare the skin aging of two rat strains, Wistar and Brown Norway (BN), considered as "poorly aging" and "healthy aging" models, respectively, and to assess the effect of alpha-lipoic acid (LPA), especially on skin microcirculation. To this purpose, various skin characteristics were studied at 6, 12, and 24 months and compared to the results of LPA treatment performed at 12 or 24 months. Skin aging occurred in both strains, but we showed an early occurrence of different age-related disorders in the Wistar strain compared to BN strain, especially regarding weight gain, glycemia dysregulation, basal skin perfusion, endothelial function, and skin resistance to low pressure. LPA treatment tended to improve skin resistance to low pressure in BN but not in Wistar despite the improvement of basal skin perfusion, endothelial function, and skin sensory sensitivity. Overall, this study confirmed the healthier aging of BN compared to Wistar strain and the positive effect of LPA on both general state and skin microcirculation.

Methionine restriction - Association with redox homeostasis and implications on aging and diseases

Methionine is an essential amino acid, involved in the promotion of growth, immunity, and regulation of energy metabolism. Over the decades, research has long focused on the beneficial effects of methionine supplementation, while data on positive effects of methionine restriction (MR) were first published in 1993. MR is a low-methionine dietary intervention that has been reported to ameliorate aging and aging-related health concomitants and diseases, such as obesity, type 2 diabetes, and cognitive disorders. In addition, MR seems to be an approach to prolong lifespan which has been validated extensively in various animal models, such as Caenorhabditis elegans, Drosophila, yeast, and murine models. MR appears to be associated with a reduction in oxidative stress via so far mainly undiscovered mechanisms, and these changes in redox status appear to be one of the underlying mechanisms for lifespan extension and beneficial health effects. In the present review, the association of methionine metabolism pathways with redox homeostasis is described. In addition, the effects of MR on lifespan, age-related implications, comorbidities, and diseases are discussed.

The Potential Roles of Dietary Anthocyanins in Inhibiting Vascular Endothelial Cell Senescence and Preventing Cardiovascular Diseases

Cardiovascular disease (CVD) is a group of diseases affecting the heart and blood vessels and is the leading cause of morbidity and mortality worldwide. Increasingly more evidence has shown that the senescence of vascular endothelial cells is the key to endothelial dysfunction and cardiovascular diseases. Anthocyanin is a type of water-soluble polyphenol pigment and secondary metabolite of plant-based food widely existing in fruits and vegetables. The gut microbiome is involved in the metabolism of anthocyanins and mediates the biological activities of anthocyanins and their metabolites, while anthocyanins also regulate the growth of specific bacteria in the microbiota and promote the proliferation of healthy anaerobic flora. Accumulating studies have shown that anthocyanins have antioxidant, anti-inflammatory, and anti-aging effects. Many animal and in vitro experiments have also proven that anthocyanins have protective effects on cardiovascular-disease-related dysfunction. However, the molecular mechanism of anthocyanin in eliminating aging endothelial cells and preventing cardiovascular diseases is very complex and is not fully understood. In this systematic review, we summarize the metabolism and activities of anthocyanins, as well as their effects on scavenging senescent cells and cardioprotection.

Relationship between aging-related pulmonary function, cognition, motor function, and activities of daily living in older adults with dementia

BACKGROUND: The aging process is related to cerebrovascular dysfunction and physiological changes, such as reduced pulmonary function. This ultimately induces cognitive impairment or dementia. OBJECTIVE: This study aimed to determine the relationship between aging-related pulmonary function, cognition, motor function, and activities of daily living (ADLs) in older adults with dementia. METHODS: This cross-sectional study included 69 older adults diagnosed with dementia. Aging-related pulmonary function and cognition were measured using a hand-held spirometer and the Korean version of the Mini-Mental State Examination (MMSE-K), respectively. To assess motor function and ADLs, the Berg Balance Scale (BBS), 10-meter walk test (10-MWT), 6-minute walk test (6-MWT), and modified Barthel index (MBI) were used to measure balance, walking speed, physical functional capacity (or walking tolerance), and ADLs, respectively. All data were analyzed using the Pearson’s product correlation coefficient (r). RESULTS: Forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) as measures of aging-related pulmonary function correlated only with the 6-MWT (FVC: r = 0.483, p = 0.002; FEV1: r = 0.512, p = 0.001). In cognitive function, MMSE-K was associated with BBS (r = 0.283, p = 0.022) and MBI (r = 0.454, p = 0.000). Additionally, there were significant correlations (r = 0.425–0.671, p = 0.000) between all motor function and ADLs measures in older adults with dementia. CONCLUSIONS: Our findings demonstrated that aging-pulmonary function was related to a lower physical functional capacity, and hence, suggested that the reduced pulmonary function were unable to walk for longer distance in older adults with dementia.

Assessment of microvascular rarefaction in human brain disorders using physiological magnetic resonance imaging

Cerebral microvascular rarefaction, the reduction in number of functional or structural small blood vessels in the brain, is thought to play an important role in the early stages of microvascular related brain disorders. A better understanding of its underlying pathophysiological mechanisms, and methods to measure microvascular density in the human brain are needed to develop biomarkers for early diagnosis and to identify targets for disease modifying treatments. Therefore, we provide an overview of the assumed main pathophysiological processes underlying cerebral microvascular rarefaction and the evidence for rarefaction in several microvascular related brain disorders. A number of advanced physiological MRI techniques can be used to measure the pathological alterations associated with microvascular rarefaction. Although more research is needed to explore and validate these MRI techniques in microvascular rarefaction in brain disorders, they provide a set of promising future tools to assess various features relevant for rarefaction, such as cerebral blood flow and volume, vessel density and radius and blood-brain barrier leakage.

Resting-state functional magnetic resonance imaging signal variations in aging: The role of neural activity

Resting‐state functional magnetic resonance imaging (rs‐fMRI) has been extensively used to study brain aging, but the age effect on the frequency content of the rs‐fMRI signal has scarcely been examined. Moreover, the neuronal implications of such age effects and age–sex interaction remain unclear. In this study, we examined the effects of age and sex on the rs‐fMRI signal frequency using the Leipzig mind–brain–body data set. Over a frequency band of up to 0.3 Hz, we found that the rs‐fMRI fluctuation frequency is higher in the older adults, although the fluctuation amplitude is lower. The rs‐fMRI signal frequency is also higher in men than in women. Both age and sex effects on fMRI frequency vary with the frequency band examined but are not found in the frequency of physiological‐noise components. This higher rs‐fMRI frequency in older adults is not mediated by the electroencephalograph (EEG)‐frequency increase but a likely link between fMRI signal frequency and EEG entropy, which vary with age and sex. Additionally, in different rs‐fMRI frequency bands, the fMRI‐EEG amplitude ratio is higher in young adults. This is the first study to investigate the neuronal contribution to age and sex effects in the frequency dimension of the rs‐fMRI signal and may lead to the development of new, frequency‐based rs‐fMRI metrics. Our study demonstrates that Fourier analysis of the fMRI signal can reveal novel information about aging. Furthermore, fMRI and EEG signals reflect different aspects of age‐ and sex‐related brain differences, but the signal frequency and complexity, instead of amplitude, may hold their link.

DRG2 Depletion Promotes Endothelial Cell Senescence and Vascular Endothelial Dysfunction

Endothelial cell senescence is involved in endothelial dysfunction and vascular diseases. However, the detailed mechanisms of endothelial senescence are not fully understood. Here, we demonstrated that deficiency of developmentally regulated GTP-binding protein 2 (DRG2) induces senescence and dysfunction of endothelial cells. DRG2 knockout (KO) mice displayed reduced cerebral blood flow in the brain and lung blood vessel density. We also determined, by Matrigel plug assay, aorta ring assay, and in vitro tubule formation of primary lung endothelial cells, that deficiency in DRG2 reduced the angiogenic capability of endothelial cells. Endothelial cells from DRG2 KO mice showed a senescence phenotype with decreased cell growth and enhanced levels of p21 and phosphorylated p53, γH2AX, senescence-associated β-galactosidase (SA-β-gal) activity, and senescence-associated secretory phenotype (SASP) cytokines. DRG2 deficiency in endothelial cells upregulated arginase 2 (Arg2) and generation of reactive oxygen species. Induction of SA-β-gal activity was prevented by the antioxidant N-acetyl cysteine in endothelial cells from DRG2 KO mice. In conclusion, our results suggest that DRG2 is a key regulator of endothelial senescence, and its downregulation is probably involved in vascular dysfunction and diseases.

Identifying peripheral arterial disease in the elderly patients using machine-learning algorithms

BACKGROUND

Peripheral artery disease (PAD) is a common syndrome in elderly people. Recently, artificial intelligence (AI) algorithms, in particular machine-learning algorithms, have been increasingly used in disease diagnosis.

AIM

In this study, we designed an effective diagnostic model of PAD in the elderly patients using artificial intelligence.

METHODS

The study was performed with 539 participants, all over 80 years in age, who underwent the measurements of Doppler ultrasonography and ankle-brachial pressure index (ABI). Blood samples were collected. ABI and two machine-learning algorithms (MLAs)-logistic regression and a random forest (RF) model-were established to diagnose PAD. The sensitivity and specificity of the models were analyzed. An additional RF model was designed based on the most significant features of the original RF model and a prospective study was conducted to demonstrate its external validity.

RESULTS

Thirteen of the 28 features introduced to the MLAs differed significantly between PAD and non-PAD participants. The respective sensitivities and specificities of logistic regression, RF, and ABI were as follows: logistic regression (81.5%, 83.8%), RF (89.3%, 91.6%) and ABI (85.1%, 84.5%). In the prospective study, the newly designed RF model based on the most significant seven features exhibited an acceptable performance rate for the diagnosis of PAD with 100.0% sensitivity and 90.3% specificity.

CONCLUSIONS

An RF model was a more effective method than the logistic regression and ABI for the diagnosis of PAD in an elderly cohort.

Extracellular Matrix in Aging Aorta

The aging population is booming all over the world and arterial aging causes various age-associated pathologies such as cardiovascular diseases (CVDs). The aorta is the largest elastic artery, and transforms pulsatile flow generated by the left ventricle into steady flow to maintain circulation in distal tissues and organs. Age-associated structural and functional changes in the aortic wall such as dilation, tortuousness, stiffening and losing elasticity hamper stable peripheral circulation, lead to tissue and organ dysfunctions in aged people. The extracellular matrix (ECM) is a three-dimensional network of macromolecules produced by resident cells. The composition and organization of key ECM components determine the structure-function relationships of the aorta and therefore maintaining their homeostasis is critical for a healthy performance. Age-associated remodeling of the ECM structural components, including fragmentation of elastic fibers and excessive deposition and crosslinking of collagens, is a hallmark of aging and leads to functional stiffening of the aorta. In this mini review, we discuss age-associated alterations of the ECM in the aortic wall and shed light on how understanding the mechanisms of aortic aging can lead to the development of efficient strategy for aortic pathologies and CVDs.

PGF2α-FP Receptor Ameliorates Senescence of VSMCs in Vascular Remodeling by Src/PAI-1 Signal Pathway

Senescence in vascular smooth muscle cells (VSMCs) is involved in vascular remodeling of aged mice. ProstaglandinF2α- (PGF2α-) FP receptor plays a critical role in cardiovascular diseases (CVDs), hypertension, and cardiac fibrosis. However, its role in senescence-induced arteriosclerosis is yet to be fully elucidated. In this study, we found that FP receptor expression increased in aged mouse aortas and senescence VSMCs. FP receptor gene silencing can ameliorate vascular aging and inhibit oxidative stress, thereby reducing the expression of PAI-1, inhibiting the activation of MMPs, and ultimately improving the excessive deposition of ECM and delaying the process of vascular fibrosis. FP receptor could promote VSMC senescence by upregulated Src/PAI-1 signal pathway, and inhibited FP receptor/Src/PAI-1 pathway could ameliorate VSMCs aging in vitro, evidenced by the decrease of senescence-related proteins P16, P21, P53, and GLB1 expressions. These results suggested that FP receptor is a promoter of vascular aging, by inducing cellular aging, oxidative stress, and vascular remodeling via Src and PAI-1 upregulation.