Aging and Allostasis: Using Bayesian Network Analytics to Explore and Evaluate Allostatic Markers in the Context of Aging

New Possibilities for Evaluating the Development of Age-Related Pathologies Using the Dynamical Network Biomarkers Theory

Aging is the slowest process in a living organism. During this process, mortality rate increases exponentially due to the accumulation of damage at the cellular level. Cellular senescence is a well-established hallmark of aging, as well as a promising target for preventing aging and age-related diseases. However, mapping the senescent cells in tissues is extremely challenging, as their low abundance, lack of specific markers, and variability arise from heterogeneity. Hence, methodologies for identifying or predicting the development of senescent cells are necessary for achieving healthy aging. A new wave of bioinformatic methodologies based on mathematics/physics theories have been proposed to be applied to aging biology, which is altering the way we approach our understand of aging. Here, we discuss the dynamical network biomarkers (DNB) theory, which allows for the prediction of state transition in complex systems such as living organisms, as well as usage of Raman spectroscopy that offers a non-invasive and label-free imaging, and provide a perspective on potential applications for the study of aging.

Allostatic load as predictor of mortality: a cohort study from Lolland-Falster, Denmark

OBJECTIVES

The purposes of the present study were to determine the association between (1) 10 individual biomarkers and all-cause mortality; and between (2) allostatic load (AL), across three physiological systems (cardiovascular, inflammatory, metabolic) and all-cause mortality.

DESIGN

Prospective cohort study.

SETTING

We used data from the Lolland-Falster Health Study undertaken in Denmark in 2016-2020 and used data on systolic blood pressure (SBP) and diastolic blood pressure (DBP), pulse rate (PR), waist-hip ratio (WHR) and levels of low-density lipoprotein cholesterol (LDL-c), high-density lipoprotein cholesterol (HDL-c), triglycerides, glycated haemoglobin A1c (HbA1c), C-reactive protein (CRP) and serum albumin. All biomarkers were divided into quartiles with high-risk values defined as those in the highest (PR, WHR, triglycerides, HbA1c, CRP) or lowest (HDL-c, albumin) quartile, or a combination hereof (LDL-c, SBP, DBP). The 10 biomarkers were combined into a summary measure of AL index. Participants were followed-up for death for an average of 2.6 years.

PARTICIPANTS

We examined a total of 13 725 individuals aged 18+ years.

PRIMARY OUTCOME MEASURE

Cox proportional hazard regression (HR) analysis were performed to examine the association between AL index and mortality in men and women.

RESULTS

All-cause mortality increased with increasing AL index. With low AL index as reference, the HR was 1.33 (95% CI: 0.89 to 1.98) for mid AL, and HR 2.37 (95% CI: 1.58 to 3.54) for high AL.

CONCLUSIONS

Elevated physiological burden measured by mid and high AL index was associated with a steeper increase of mortality than individual biomarkers.

Neutralizing a Springboard for Inflammation: Physical Activity to Control the Immune Network

The severe consequences of the present Corona Virus Disease 2019 COVID-19 pandemic seem to be closely related to an already ongoing ('first') pandemic, directly associated with a sedentary lifestyle. It seems evident that the prognosis after infection is substantially worse for individuals suffering from, for example, (visceral) obesity, cardiovascular disease, and diabetes type 2. Consequently, it may be considered highly relevant to gain insight into the potential beneficial effects of exercise interventions to strengthen the immune system, particularly in high-risk populations. For this reason, the exercise protocols that are suggested to strengthen the immune system, which can be executed by all ages and almost all physical conditions, were reviewed and evaluated. Previously published protocols range from interrupting prolonged sitting, to regular low-to-moderate exercise activities, to high intensity, typically interval, sports formats. Reported positive effects on immune functioning appear to be induced either directly or via beneficial metabolic and/or psychological effects and become measurable after 3 weeks to 3 months. Based in these findings, it appeared possible to design an optimal exercise protocol to maximize effects on immune functioning that should be executable for all, even under restricted ('lockdown') circumstances.

The Applicability of the Poincaré Plot in the Analysis of Variability of Reaction Time during Serial Testing

(1) Background: This study aims to put into evince the relationship between the variability of the reaction time (RT) during repeated testing, expressed through indicators extracted by the Poincaré plot method, and the age of the participants, their self-reported health (SRH), and level of perceived anxiety. (2) Methods: The study was performed using computerized RT testing software. An observational cross-sectional study was performed on a group of 120 subjects (mean age 42.33 ± 21.12 years), sex ratio men to women 1.14:1. Data were processed through descriptive and inferential statistics. The Poincaré plot method was applied in the analysis of the RT series of data, by calculating the indicators SD₁, SD₂, SD₁/SD₂, and area of the fitting ellipse (AFE) (3) Results: We provided evidence of the excellent reliability of the web-based RT serial testing (Cronbach’s Alpha 0.991) with this sample group. Our results showed that age is an important predictor for mean values of RT, while SD₁, SD₂, and AFE indicators are for SRH (p < 0.01). (4) Conclusions: the variability of RT, expressed by the Poincaré plot indicators, reflects the health status rather than the aging of the subjects and is barely influenced by their level of anxiety.