Anti-VIM monoclonal antibody, clone FQS4887 [Alexa Fluor® 594] Knockout Validated

Astrocytes are commonly identified by their expression of the intermediate filament protein glial fibrillary acidic protein (GFAP). GFAP-immunoreactive (GFAP-IR) astrocytes exhibit regional heterogeneity in density and morphology in the mouse brain as well as morphological diversity in the human cortex. However, regional variations in astrocyte distribution and morphology remain to be assessed comprehensively. This was the overarching objective of this postmortem study, which mainly exploited the immunolabeling of vimentin (VIM), an intermediate filament protein expressed by astrocytes and endothelial cells which presents the advantage of more extensively labeling cell structures. We compared the densities of vimentin-immunoreactive (VIM-IR) and GFAP-IR astrocytes in various brain regions (prefrontal and primary visual cortex, caudate nucleus, mediodorsal thalamus) from male individuals having died suddenly in the absence of neurological or psychiatric conditions. The morphometric properties of VIM-IR in these brain regions were also assessed. We found that VIM-IR astrocytes generally express the canonical astrocytic markers Aldh1L1 and GFAP but that VIM-IR astrocytes are less abundant than GFAP-IR astrocytes in all human brain regions, particularly in the thalamus, where VIM-IR cells were nearly absent. About 20% of all VIM-IR astrocytes presented a twin cell morphology, a phenomenon rarely observed for GFAP-IR astrocytes. Furthermore VIM-IR astrocytes in the striatum were often seen to extend numerous parallel processes which seemed to give rise to large VIM-IR fiber bundles projecting over long distances. Moreover, morphometric analyses revealed that VIM-IR astrocytes were more complex than their mouse counterparts in functionally homologous brain regions, as has been previously reported for GFAP-IR astrocytes. Lastly, the density of GFAP-IR astrocytes in gray and white matter were inversely correlated with vascular density, but for VIM-IR astrocytes this was only the case in gray matter, suggesting that gliovascular interactions may especially influence the regional heterogeneity of GFAP-IR astrocytes. Taken together, these findings reveal special features displayed uniquely by human VIM-IR astrocytes and illustrate that astrocytes display important region- and marker-specific differences in the healthy human brain.

This cohort study assesses whether long-term variability and rate of change of blood pressure from young adulthood to midlife are associated with cardiovascular disease and all-cause mortality by middle age. Importance Determining blood pressure (BP) patterns in young adulthood that are associated with cardiovascular disease (CVD) events in later life may help to identify young adults who have an increased risk for CVD. Objective To determine whether the long-term variability of BP across clinical visits and the rate of change in BP from young adulthood to midlife are associated with CVD and all-cause mortality by middle age, independently of mean BP during young adulthood and a single BP in midlife. Design, Setting, and Participants This prospective cohort study included a community-based sample of 3394 African American and white participants in the Coronary Artery Risk Development in Young Adults (CARDIA) Study, enrolled from March 1985 through June 1986. Patterns of systolic BP (SBP) were evaluated with measurements at year 0 (baseline) and 2, 5, 7, and 10 years after baseline. Visit-to-visit SBP variability was estimated as BP variability independent of the mean (VIM). Data were collected from March 1985 through August 2015 and analyzed from June through October 2019. Main Outcomes and Measures Cardiovascular disease and all-cause mortality experienced through August 2015 were adjudicated. The associations of each SBP pattern with CVD events and all-cause mortality were determined using Cox proportional hazards regression models. Results At year 10, the mean (SD) age of the 3394 participants was 35.1 (3.6) years; 1557 (45.9%) were African American; 1892 (55.7%) were women; and 103 (3.0%) were taking antihypertensive medication. During a median follow-up of 20.0 (interquartile range, 19.4-20.2) years, 162 CVD events and 181 deaths occurred. When all BP pattern measurements were entered into the same model including a single SBP measurement at the year 10 examination, the hazard ratios for CVD events for each 1-SD increase in SBP measures were 1.25 (95% CI, 0.90-1.74) for mean SBP, 1.23 (95% CI, 1.07-1.43) for VIM SBP, and 0.99 (95% CI, 0.81-1.26) for annual change of SBP. The VIM for SBP was the only BP pattern associated with all-cause mortality (hazard ratio, 1.24; 95% CI, 1.09-1.41). Conclusions and Relevance The results of this study suggest that the assessment of visit-to-visit SBP variability may help identify young adults at increased risk for CVD and all-cause mortality later in life. Question Is the long-term variability of blood pressure across clinical visits from young adulthood to midlife associated with cardiovascular disease and all-cause mortality by middle age? Findings In a cohort study of 3394 African American and white individuals, higher long-term visit-to-visit systolic blood pressure variability from young adulthood to midlife was associated with an increased risk for cardiovascular disease and all-cause mortality by middle age. Meaning These findings suggest that the assessment of visit-to-visit systolic blood pressure variability may help identify young adults at increased risk for cardiovascular disease and all-cause mortality.