Shifts in lifestyle and socioeconomic circumstances predict change-for better or worse-in speed of epigenetic aging: A study of middle-aged black women.

BACKGROUND: While numerous studies have documented the power of new generation epigenetic clocks to predict morbidity and mortality, research regarding the causes of variation in speed of epigenetic aging is in the early stages. To the extent that these epigenetic clocks are robust measures of biological aging, they should be sensitive to various nutritional, behavioral, ecological, and social factors that have been shown to affect health. OBJECTIVE: Investigate over an 11-year period the extent to which changes in socioeconomic stress and lifestyle predict changes in speed of epigenetic aging among a sample of middle-aged African American women. METHODS: Using data from the Family and Community Health Study, we investigated whether changes in socioeconomic stress, diet, smoking, exercise, alcohol consumption, and relationship status predict changes in speed of biological aging assessed with 3 s-generation epigenetic clocks: AccelGrimAge, DunedinPoAm, and AccelPhenoAge. The study was able to avoid the challenges associated with self-reports of diet and smoking by employing recently developed epigenetic measures. RESULTS: Changes in socioeconomic stress and diet were associated with changes in speed of biological aging as assessed by all three epigenetic clocks, and changes in smoking was related to changes in AccelGrimAge and DunedinPoAm. Analyses controlling for cell-type indicated that in large measure diet exerts its effect on aging through its impact on the immune system. CONCLUSIONS: These findings suggest that adoption of a healthy diet and reduction in the use of tobacco are related to a decrease in epigenetic aging, whereas increased pressure relating to income, housing and economic independence are associated with an increase in the speed of aging. These effects were especially strong for the two epigenetic clocks AccelGrimAge and DunedinPoAm. Overall, the results indicate that stress and lifestyle changes may, for better or worse, influence the "biological weathering" often experienced by middle-aged African American women.

Unstable Childhood, Adult Adversity, and Smoking Accelerate Biological Aging Among Middle-Age African Americans: Similar Findings for GrimAge and PoAm.

Objectives: The recent biological clocks GrimAge and PoAm are robust predictors of morbidity and mortality. Little research, however, has investigated the factors that influence their ticking speed. No study has used multivariate analyses to examine whether childhood adversity, adult hardship, lifestyle practices, or some combination of these factors best explains acceleration of these indices. Methods: Using a sample of 506 middle-age African Americans, the present study investigated the extent to which childhood instability, adult adversity, and lifestyle predict accelerated GrimAge and PoAm. Results: The two clocks were highly correlated and the pattern of findings was very similar for the two measures. Childhood instability, adult financial hardship, and smoking were significant predictors of both clocks. Discussion: The findings support a life course perspective where both the long arm of childhood as well as later life conditions influence speed of aging. Similar results across the two clocks enhance confidence in the findings.

The Cost of Being Cool: How Adolescent Pseudomature Behavior Maps onto Adult Adjustment.

During adolescence, one's status among peers is a major concern. Such status is often largely a function of popularity and establishing oneself as "cool." While there are conventional avenues to achieving status among adolescents, engaging in adult-like, or pseudomature, behaviors such as substance use or sexual activity is a frequent occurrence. Although past research has examined the consequences of adolescent delinquency, what remains unclear is the long-term fate of adolescents who are both popular and antisocial. Using data from a sample of African American males (N = 339) we employ latent class analysis to examine the adult consequences of achieving popularity during adolescence by engaging in pseudomature behavior. Our results identified four classes of adolescents: the conventionals, the pseudomatures, the delinquents, and the detached. The conventionals were low on popularity, pseudomature behavior, and affiliation with deviant peers but high on academic commitment. The pseudomatures were high on popularity, adult-like behavior, and academic commitment but low on affiliation with delinquent peers. The delinquents were low on popularity and school achievement but high on pseudomature behavior and affiliations with delinquent peers. Finally, the detached were low on school commitment, popularity and pseudomature behavior but they report high involvement with a delinquent peer group. By early adulthood, the costs of adolescent adult-like behavior were evident. Early popularity and academic commitment did not portend later social competence or college completion for the pseudomatures. Instead, they frequently experienced an early transition to parenthood, a likely consequence of precocious sexual activity. These findings suggest that interventions should not focus only on the most delinquent adolescents but also need to attend to the pseudomature students who are brimming with promise but are flirting with behaviors that may subvert realization of this potential.

Childhood/Adolescent stressors and allostatic load in adulthood: Support for a calibration model.

RATIONALE: Past research has established an association between childhood and adolescent stressors and elevated inflammatory and metabolic biomarkers in adulthood, but questions remain about the theoretical model most suited to explain this association. OBJECTIVE: This study examined alternative hypotheses from four theoretical models regarding the link between exposure to stressful early life circumstances and cumulative biological risk, or allostatic load, in adulthood. METHODS: Multivariate regression models and data from a sample of 327 African American women from the Family and Community Health Study were used to test hypotheses. RESULTS: Stressors measured during the phases of childhood and adolescence predicted increased allostatic load, irrespective of adult circumstances that might account for this effect. Also, these early stressors conditioned the health effects of adult positive and negative circumstances. Exposure to childhood and adolescent stressors amplified the effect of adult economic hardship on allostatic load and dulled the beneficial effects of positive events and high-quality relationships. CONCLUSION: These findings support the perspective that childhood and adolescence are phases when exposure to adversities possibly enhances vulnerability to biological risk in adulthood irrespective of later life circumstances. Also, the findings are consistent with the perspective that childhood and adolescent adversities calibrate biological risk resulting from aversive and positive features of the adult social environment.

Osteoblast lineage cells can discriminate microscale topographic features on titanium-aluminum-vanadium surfaces.

Titanium (Ti) and Ti alloys are used in orthopaedic/spine applications where biological implant fixation, or osseointegration, is required for long-term stability. These implants employ macro-scale features to provide mechanical stability until arthrodesis, features that are too large to influence healing at the cellular level. Micron-scale rough Ti alloy (Ti-6Al-4V) increases osteoblastic differentiation and osteogenic factor production in vitro and increases in vivo bone formation; however, effects of overall topography, including sub-micron scale and nanoscale features, on osteoblast lineage cells are less well appreciated. To address this, Ti6Al4V surfaces with macro/micro/nano-textures were generated using sand blasting and acid etching that had comparable average roughness values but differed in other roughness parameters (total roughness, profile roughness, maximum peak height, maximum valley depth, root-mean-squared roughness, kurtosis, skewness) (#5, #9, and #12). Human mesenchymal stem cells (HMSCs) and normal human osteoblasts (NHOst) were cultured for 7 days on the substrates and then analyzed for alkaline phosphatase activity and osteocalcin content, production of osteogenic local factors, and integrin subunit expression. All three surfaces supported osteoblastic differentiation of HMSCs and further maturation of NHOst cells, but the greatest response was seen on the #9 substrate, which had the lowest skewness and kurtosis. The #9 surface also induced highest expression of α2 and ß1 integrin mRNA. HMSCs produced highest levels of ITGAV on #9, suggesting this integrin may play a role for early lineage cells. These results indicate that osteoblast lineage cells are sensitive to specific micro/nanostructures, even when overall macro roughness is comparable and suggest that skewness and kurtosis are important variables.

On the design and analysis of competent selecto-recombinative GAs.

In this paper, we study two recent theoretical models--a population-sizing model and a convergence model--and examine their assumptions to gain insights into the conditions under which selecto-recombinative GAs work well. We use these insights to formulate several design rules to develop competent GAs for practical problems. To test the usefulness of the design rules, we consider as a case study the map-labeling problem, an NP-hard problem from cartography. We compare the predictions of the theoretical models with the actual performance of the GA for the map-labeling problem. Experiments show that the predictions match the observed scale-up behavior of the GA, thereby strengthening our claim that the design rules can guide the design of competent selecto-recombinative GAs for realistic problems.