Quantitative Fluorescence Imaging of the Intracellular Redox State by Real-Time Spatial and Temporal Simultaneous Analysis of O2•- Levels and Keap1 Translocation.

Dysregulated redox homeostasis under pathological conditions can eventually culminate in oxidative stress and associated disease damage. Spatial and temporal regulation of intracellular redox states involves two crucial parameters for elucidating oxidative stress-related molecular mechanisms. However, the lack of methods for real-time analysis of redox states is a considerable hurdle for the in-depth interpretation of pathogenic mechanisms. Herein, given the over-produced reactive oxygen species (ROS) and the translocation of redox-sensitive proteins as the potential biomarkers of oxidative stress, we developed a novel ROS-macromolecular protein synergistic imaging strategy that relied on a small-molecule fluorescent CPR-SK probe. The CPR-SK specifically activated the caffeic acid moieties or targeting peptides (EWWW) toward the biomarkers, including superoxide (O2•-) fluctuations and Keap1 translocation, achieving simultaneous real-time imaging of dual molecular events during oxidative stress. Importantly, in situ, CPR-SK exhibited both gentle elevation of O2•- and subsequent migration of Keap1 from the cytoplasm to the nucleus, which were key indicators for determining slight injuries induced by hepatic ischemia-reperfusion. The results clearly demonstrated that this spatiotemporal imaging method was a reliable tool for analyzing dynamic intracellular changes of the redox state and elucidating the molecular mechanisms of oxidative stress-related diseases.

Sex differences in the association between cardiovascular diseases and dementia subtypes: a prospective analysis of 464,616 UK Biobank participants.

BACKGROUND: Whether the association of cardiovascular diseases (CVDs) with dementia differs by sex remains unclear, and the role of socioeconomic, lifestyle, genetic, and medical factors in their association is unknown. METHODS: We used data from the UK Biobank, a population-based cohort study of 502,649 individuals. We used Cox proportional hazards models to estimate sex-specific hazard ratios (HRs) and 95% confidence intervals (CI), and women-to-men ratio of HRs (RHR) for the association between CVD (coronary heart diseases (CHD), stroke, and heart failure) and incident dementia (all-cause dementia, Alzheimer's Disease (AD), and vascular dementia (VD)). The moderator roles of socioeconomic (education, income), lifestyle (smoking, BMI, leisure activities, and physical activity), genetic factors (APOE allele status), and medical history were also analyzed. RESULTS: Compared to people who did not experience a CVD event, the HRs (95%CI) between CVD and all-cause dementia were higher in women compared to men, with an RHR (Female/Male) of 1.20 (1.13, 1.28). Specifically, the HRs for AD were higher in women with CHD and heart failure compared to men, with an RHR (95%CI) of 1.63 (1.39, 1.91) and 1.32 (1.07, 1.62) respectively. The HRs for VD were higher in men with heart failure than women, with RHR (95%CI) of 0.73 (0.57, 0.93). An interaction effect was observed between socioeconomic, lifestyle, genetic factors, and medical history in the sex-specific association between CVD and dementia. CONCLUSION: Women with CVD were 1.5 times more likely to experience AD than men, while had 15% lower risk of having VD than men.

In Situ Observation of mtDNA Damage during Hepatic Ischemia-Reperfusion.

Hepatic ischemia-reperfusion (IR) injury is a severe pathophysiological event during liver surgery or transplantation and could lead to liver failure or even death. The energy supply of mitochondria plays an essential role in preventing IR injury. Mitochondrial DNA (mtDNA) is involved in maintaining the balance of energy by participating in an oxidative phosphorylation process. However, the exact relationship between IR and mtDNA remains unclear by reason of the lack of an accurate real-time analysis method. Herein, we fabricated a mitochondria-targeting fluorescent probe (mtDNA-BP) to explore mtDNA stability and supervise the changes in mtDNA in IR liver. By virtue of pyridinium electropositivity and suitable size, mtDNA-BP could accumulate in mitochondria and insert into the mtDNA groove, which made mtDNA-BP fluoresce strongly. This is attributed to the reduction of the intramolecular rotation energy loss that is restricted by DNA. By in situ fluorescence imaging, we observed in real time that mtDNA damage was aggravated by deteriorating IR injury, so the ROS-mtDNA-mediated IR damage signal pathway was speculated. Furthermore, on the basis of mtDNA-BP real-time response capability for mtDNA, we established a drug-screening method for inhibiting IR injury and found superior therapeutic performance of two potential drugs: pioglitazone and salidroside. This work contributes to our understanding of mtDNA-related disease and provides a new drug analysis method.