Hesperetin induces an apoptosis-triggered extrinsic pathway and a p53- independent pathway in human lung cancer H522 cells

We studied the chemoprevention property of hesperetin on H522 cells using MTT, an apoptosis assay, an analysis of cell cycle progression, and the mitochondrial membrane potential, and apoptotic marker gene expression was determined using quantitative PCR. Hesperetin enhanced apoptotic cell death and mitochondrial membrane potential loss in H522 cells. Hesperetin up-regulated the levels of Fas, FADD, and caspase-8 expression and downregulted the levels of caspase-3 and caspase-9, p53, and Bax expression in H522 cells. This study shows that hesperetin induces apoptosis in H522 cells via a pathway independentof p53 and Bax but triggers the death-receptor Fas-initiated FADD/ caspase-8-dependent apoptotic pathway.

Single nucleotide polymorphisms in the p21 and bcl2 cancer susceptibility genes and breast cancer risk in Saudi Arabia

Certain single nucleotide polymorphisms (SNPs) in genes like p21 or bcl2 increase susceptibility to breast cancer but it has not, until now, been clear whether common polymorphic variants in the same genes also increase risk in Saudi Arabian population. The aim of this study was therefore to determine whether polymorphisms of p21 or Bcl2 might be associated with an increased risk of breast cancer in Saudi women. p21 (rs733590) C/T SNP was not found to be associated with breast cancer pathogenesis. However, we found that a reverse mutation T/C might be linked with breast cancer occurrence. Bcl2 genotypes were marginally associated overall with breast cancer risk. In addition, the alleles of this gene were significantly associated with risk of breast cancer. The allelic frequency of G was higher (0.68) in patients than in healthy women. AA vs. AG+GG genotype [OR=3.56 (1.24-10.68); P=0.008] was the dominant genotype. It is likely that these genes conferring measurably increased risks of breast cancer in our study population.

Adherence to Life's Essential 8 is associated with delayed white matter aging

Importance

The American Heart Association introduced Life's Essential 8 (LE8) as a checklist of healthy lifestyle factors to help older individuals maintain and improve cardiovascular health and live longer. How LE8 can foster healthy brain aging and interact with genetic risk factors to render the aging brain less vulnerable to dementia is not well understood.

Objective

To investigate the impact of LE8 on the white matter brain aging and the moderating effects of the APOE4 allele.

Design Setting and Participants

This cross-sectional study uses genetic, imaging, and other health-related data collected in the UK Biobank cohort. Participants included non-pregnant whites with LE8 variables, diffusion tensor imaging data, and genetic data on APOE4 available, and excluded the extreme white matter hyperintensities. The baseline assessment was performed from 2006 to 2010. The diffusion tensor imaging data were collected since 2014.

Exposures

LE8 variables, encompassing diet, physical activity, smoking, sleep, body mass index, lipids, hemoglobin, and blood pressure.

Main Outcomes and Measures

The white matter brain age was predicted from regional fractional anisotropy measures derived from diffusion tensor imaging data using the random forest regression method. The outcome white matter brain age gap was calculated by subtracting individuals' chronological age from their predicted brain age.

Results

The analysis included 9,430 women and 9,387 men (mean age 55.45 [SD: 7.46] years). Higher LE8 scores were associated with lower white matter brain age gap, indicating delayed brain aging. The findings are consistent for each of the individual LE8 variables. The effect was stronger among non- APOE4 carriers (124 days younger per 10-point increase, 95% CI, 102 to 146 days; P<0.001) than APOE4 carriers (84 days younger per 10-point increase, 95% CI, 47 to 120 days; P<0.001). Notably, early middle-aged women with APOE4 showed significant interactions between LE8 scores and brain aging (P interaction = 0.048), not observed in men.

Conclusions and Relevance

Adherence to LE8 is associated with delayed brain aging, moderated by genetic factors such as APOE4 . These findings highlight the potential of behavioral and lifestyle interventions in reducing dementia risk, emphasizing tailored prevention plans for those with different genetic predispositions to dementia and sex.

Association between allostatic load and accelerated white matter brain aging: findings from the UK biobank

White matter (WM) brain age, a neuroimaging-derived biomarker indicating WM microstructural changes, helps predict dementia and neurodegenerative disorder risks. The cumulative effect of chronic stress on WM brain aging remains unknown. In this study, we assessed cumulative stress using a multi-system composite allostatic load (AL) index based on inflammatory, anthropometric, respiratory, lipidemia, and glucose metabolism measures, and investigated its association with WM brain age gap (BAG), computed from diffusion tensor imaging data using a machine learning model, among 22 951 European ancestries aged 40 to 69 (51.40% women) from UK Biobank. Linear regression, Mendelian randomization, along with inverse probability weighting and doubly robust methods, were used to evaluate the impact of AL on WM BAG adjusting for age, sex, socioeconomic, and lifestyle behaviors. We found increasing one AL score unit significantly increased WM BAG by 0.29 years in association analysis and by 0.33 years in Mendelian analysis. The age- and sex-stratified analysis showed consistent results among participants 45-54 and 55-64 years old, with no significant sex difference. This study demonstrated that higher chronic stress was significantly associated with accelerated brain aging, highlighting the importance of stress management in reducing dementia and neurodegenerative disease risks.

Nongenetic and Genetic Factors Associated with White Matter Brain Aging: Exposome-Wide and Genome-Wide Association Study

BACKGROUND/OBJECTIVES

Human brain aging is a complex process that affects various aspects of brain function and structure, increasing susceptibility to neurological and psychiatric disorders. A number of nongenetic (e.g., environmental and lifestyle) and genetic risk factors are found to contribute to the varying rates at which the brain ages among individuals.

METHODS

In this paper, we conducted both an exposome-wide association study (XWAS) and a genome-wide association study (GWAS) on white matter brain aging in the UK Biobank, revealing the multifactorial nature of brain aging. We applied a machine learning algorithm and leveraged fractional anisotropy tract measurements from diffusion tensor imaging data to predict the white matter brain age gap (BAG) and treated it as the marker of brain aging. For XWAS, we included 107 variables encompassing five major categories of modifiable exposures that potentially impact brain aging and performed both univariate and multivariate analysis to select the final set of nongenetic risk factors.

RESULTS

We found current tobacco smoking, dietary habits including oily fish, beef, lamb, cereal, and coffee intake, length of mobile phone use, use of UV protection, and frequency of solarium/sunlamp use were associated with the BAG. In genetic analysis, we identified several SNPs on chromosome 3 mapped to genes IP6K1, GMNC, OSTN, and SLC25A20 significantly associated with the BAG, showing the high heritability and polygenic architecture of human brain aging.

CONCLUSIONS

The critical nongenetic and genetic risk factors identified in our study provide insights into the causal relationship between white matter brain aging and neurodegenerative diseases.