👤 John R Best

The apolipoprotein E (APOE) ε4 allele is a risk factor for late-onset Alzheimer's disease; however, risk varies by sex and lifestyle. Regular physical activity is known to mitigate cognitive decline; whether the degree of benefit differs by APOE genotype, sex, and race remains unknown. Analyses utilized data from 2,985 participants in the Health, Aging, and Body Composition (HABC) cohort, comprising community-dwelling black and white older adults followed for 10 years. Cognitive performance was assessed multiple times across the 10 years using the Digit Symbol Substitution Test (DSST) for executive functions and processing speed and the Modified Mini-Mental State Examination (3MS) for global cognition. APOE genotypes were categorized into ε2, ε3, and ε4 groups. Annual self-reported walking time was used to quantify physical activity. Linear mixed models and latent growth curve modeling examined the interactions between APOE genotype, sex, and walking on cognitive trajectories with adjustments for race, study location, health score, age, education attained, and body mass index. APOE ε4 carriers demonstrated steeper declines in both DSST and 3MS scores compared to ε3 carriers, irrespective of sex (all β<-0.13, all p < 0.004). APOE ε2 was protective longitudinally for 3MS in females only (β = 0.15, p < 0.002). Walking showed the strongest protective effect in APOE ε4 carriers for females and males in the rate of change of DSST and 3MS scores (all β > 0.27, all p < 0.044). These findings underscore the importance of public messaging about the benefits of regular physical activity for retaining cognitive function especially for persons genetically at heightened risk. Show less

Metabolic reprogramming is a major feature of many tumors including non-small cell lung cancer (NSCLC). Branched-chain α-keto acid dehydrogenase kinase (BCKDK) plays an important role in diabetes, obesity, and other diseases. However, the function of BCKDK in NSCLC is unclear. This study aimed to explore the function of BCKDK in NSCLC. Metabolites in the serum of patients with NSCLC and the supernatant of NSCLC cell cultures were detected using nuclear magnetic resonance (NMR) spectroscopy. Colony formation, cell proliferation, and cell apoptosis were assessed to investigate the function of BCKDK in the progression of NSCLC. Glucose uptake, lactate production, cellular oxygen consumption rate, extracellular acidification rate, and reactive oxygen species (ROS) were measured to examine the function of BCKDK in glucose metabolism. The expression of BCKDK was measured using reverse transcriptase-polymerase chain reaction, western blot, and immunohistochemical assay. Compared with healthy controls and postoperative NSCLC patients, increased branched-chain amino acid (BCAA) and decreased citrate were identified in the serum of preoperative NSCLC patients. Upregulation of BCKDK affected the metabolism of BCAAs and citrate in NSCLC cells. Knockout of BCKDK decreased the proliferation and exacerbated apoptosis of NSCLC cells ex vivo, while increased oxidative phosphorylation and, ROS levels, and inhibited glycolysis. BCKDK may influence glycolysis and oxidative phosphorylation by regulating the degradation of BCAA and citrate, thereby affecting the progression of NSCLC. Show less