👤 Sarah Tom

Chemokines C-X-C Motif Chemokine Ligand 9 (CXCL9) and C-C Motif Chemokine Ligand 2 (CCL2) were previously linked to incident cognitive impairment and dementia in the Northern Manhattan Study (NOMAS). We investigated whether circulating CXCL9 and CCL2 are independently associated with the cerebral white matter disease (WMD) burden and whether WMD mediates their association with prospective cognitive outcomes. In the stroke-free, prospective, community-dwelling NOMAS cohort (age≥50) we examined white matter hyperintensity volume (WMHV) on brain MRI and serum chemokine levels. WMHV was normalized, log-transformed, and standardized. Cognitive status was assessed at MRI and again 12.2±1.3 years later to adjudicate incident cognitive decline and dementia. Multivariable linear regression models with either CXCL9 or CCL2 (in quartiles) as exposures and WMHV as the outcome were adjusted for socio-demographics and key contributors to WMD, including vascular risk factors (Model 1), kidney function (2), and APOE ε4 status (3). Mediation of the CXCL9-cognitive outcome association by WMHV was tested using Monte Carlo integration. Among 1,179 participants (mean age 70±9 years; 60% female), elevated CXCL9 (Q4 vs. Q1) was associated with greater WMHV (Model 1: β=0.20, 95%CI 0.06-0.34). This association persisted even after adjusting for kidney function (Model 2: β=0.17, 95%CI 0.03-0.34) and APOE ε4 status (Model 3: β=0.19, 95%CI 0.04-0.33). CXCL9 (Q4 vs. Q1) effect magnitude in Model 3 approximated ~4 years of aging (β=0.05/year, 95%CI 0.04-0.06), exceeding that of hypertension (β=0.16, 95%CI 0.05-0.27), with a stepwise trend present across quartiles (β/quartile increase=0.07, 95%CI 0.02-0.12, p=0.003). Among 1,166 participants (dementia-free at MRI), the indirect, WMHV-mediated pathway was statistically significant for the association of CXCL9 with incident cognitive decline (ACME 0.009, 95%CI 0.002-0.018, p=0.016) and with dementia (ACME 0.008, 95%CI 0.003-0.016, p=0.004). CCL2 showed no association with WMHV. Greater CXCL9 levels were associated with greater white matter lesion load, independent of vascular, renal, and genetic factors, suggesting a role in WMD pathogenesis. WMHV mediated CXCL9's association with cognitive decline and dementia risk. This IFN-γ-induced monokine (MIG) warrants further evaluation as a biomarker of white matter and cognitive health as well as a potentially modifiable therapeutic target. Show less

Circadian disturbance (CD) is the consequence of a mismatch between endogenous circadian rhythms, behaviour, and/or environmental cycles, and frequently occurs during shift work. Shift work has been associated with elevated risk for atherosclerotic cardiovascular disease (asCVD) in humans, but evidence for the effectiveness of prevention strategies is lacking. Here, we applied time-restricted feeding (TRF) as a strategy to counteract atherosclerosis development during CD in female APOE∗3-Leiden.CETP mice, a well-established model for humanized lipoprotein metabolism. Control groups were subjected to a fixed 12:12 h light-dark cycle, while CD groups were subjected to 6-h phase advancement every 3 days. Groups had either ad libitum (AL) access to food or were subjected to TRF with restricted food access to the dark phase. TRF did not prevent the increase in the relative abundance of circulating inflammatory monocytes and elevation of (postprandial) plasma triglycerides during CD. Nonetheless, TRF reduced atherosclerotic lesion size and prevented an elevation in macrophage content of atherosclerotic lesions during CD, while it increased the relative abundance of anti-inflammatory monocytes, prevented activation of T cells, and lowered plasma total cholesterol levels and markers of hepatic cholesterol synthesis. These effects were independent of total food intake. We propose that time restricted eating could be a promising strategy for the primary prevention of asCVD risk in shift workers, which warrants future study in humans. This work was funded by the Novo Nordisk Foundation, the Netherlands Ministry of Social Affairs and Employment, Amsterdam Cardiovascular Sciences, and the Dutch Heart Foundation. Show less