bioRxiv Science⌕ Search

bioRxiv · 10.1101/2025.09.19.677480

Re-evaluating the Impact of Biological Sex on Atherosclerosis in Apoe-/- and Ldlr-/- mice

Abstract

BACKGROUNDThe progression of cardiovascular disease shows significant sexual dimorphism: although females generally develop the disease later in life, they exhibit a higher age-related incidence than males. Despite this clinical pattern, preclinical studies often overlook both sexes in their design, and existing research on sex-specific atherosclerosis in mice remains inconsistent. This study was designed to assess the influence of sex on atherosclerosis using two widely used atherosusceptible mouse models--Apoe-/- and Ldlr-/- mice. METHODSTo investigate the influence of sex on atherogenesis, we conducted a 20-week study using both male and female Apoe-/- and Ldlr-/- mice. The mice were fed an atherogenic ALMN diet (40% trans-fat, 2% cholesterol, 22% fructose) to promote plaque development. We performed comprehensive analyses of: (1) systemic metabolic parameters (lipid profile, glucose metabolism); (2) atherosclerotic burden (en face and aortic sinus plaque area); and (3) plaque composition (necrotic core size, collagen content, macrophage infiltration). RESULTSIn both models, male mice showed higher lipid levels, worse glucose tolerance, and reduced insulin sensitivity compared to females. Apoe-/- mice showed minimal sex differences in atherosclerosis with a trend toward increased plaque size in females. Plaque stability markers-- including collagen content, necrotic core size, and macrophage infiltration--did not differ significantly between sexes. In contrast, Ldlr-/- males exhibited greater en face plaque burden than females, yet plaque stability remained similar across sexes. CONCLUSIONComparative analysis of two widely used murine atherosclerosis models revealed genotype-dependent sexual dimorphism. Female Apoe-/- mice showed a non-significant trend toward larger plaque areas than males, whereas male Ldlr-/- mice developed significantly larger en face atherosclerotic plaques than females. By evaluating plaque area and composition across these models, our findings underscore the importance of including both sexes in atherosclerosis studies, in accordance with guidelines from the National Institutes of Health and the American Heart Association.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Zhao, Y., Wang, L., Berk, B. C., Strijdom, H., Huang, Y., Weng, J., Xu, S.. 2025-09-21. Re-evaluating the Impact of Biological Sex on Atherosclerosis in Apoe-/- and Ldlr-/- mice. https://doi.org/10.1101/2025.09.19.677480

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

Differential requirement for the Ire1 luminal domain in Candida albicans drug susceptibility and pathogenicity

The opportunistic human pathogen Candida albicans depends on the unfolded protein response (UPR) for cell wall integrity, antifungal tolerance, filamentous growth, and virulence. The UPR is driven by the conserved transmembrane sensor Ire1, which is activated either by misfolded proteins through its luminal domain or by lipid bilayer stress (LBS) through its transmembrane domain. In budding yeast, these two activation modes deploy divergent transcriptional programs. Whether the requirement for these two input domains is separable in C. albicans, where the cell membrane and cell wall are themselves the targets of major antifungal drug classes, remains unknown. Here, we engineered a C. albicans strain expressing Ire1 lacking an intact luminal domain (ire1{Delta}LD), which no longer detects proteotoxic stress. The ire1{Delta}LD strain grew in the presence of the azole antifungals fluconazole and miconazole but was highly sensitive to heat shock, cell wall stress, and the echinocandin caspofungin. It was also unable to sustain filamentous growth and showed reduced virulence in a Caenorhabditis elegans infection model. RNA sequencing revealed only modest changes to the steady-state transcriptome of ire1{Delta}LD cells. Together, these findings define a differential requirement for the input domains of C. albicans Ire1, uncoupling growth under azole-induced membrane stress from the cell wall, thermal, and virulence-associated outputs that depend on proteotoxic sensing, a distinction that could inform antifungal strategies targeting the UPR.

cell biology↗

Nucleosome Core Allostery Governs Chromatin Recognition and Cell Fate

Nucleosomes regulate chromatin folding, accessibility, and factor recruitment. Current models primarily attribute these functions to histone tail modifications, while the core is largely viewed as a structural scaffold. Yet subtle changes within the nucleosome core can produce profound functional consequences, and the mechanisms underlying these effects remain unclear. Here, we describe nucleosome core allostery as a fundamental principle of chromatin regulation that amplifies the impact of minimal nucleosome variations. Leveraging natural differences between H2A.Z variants, we show that the nucleosome core encodes distinct conformational dynamics that propagate allosterically, thereby controlling nucleosome accessibility and recognition by chromatin factors. As a result, a single buried amino acid substitution alone is sufficient to reprogram nucleosome dynamics and bias cell identity. Our findings establish the nucleosome core as an allosteric regulatory module and provide a generalizable framework for how subtle variation within nucleosomes is amplified into diverse biological outcomes in development and disease.

cell biology↗

A Novel Open-Source CellProfiler Pipeline for Automated, User-Friendly Hierarchical and K-Means Clustering of Microglial Morphology

Microglia represent a highly dynamic and heterogeneous cell type that is critically implicated in states of health and pathology. Microglial morphological subgroups have been identified that correspond to functional characteristics determining health-related outcomes. The identification of states based on morphological characteristics will therefore provide invaluable insights into the microglia-specific functional mechanisms driving treatment effects. The application of clustering analyses enables the detection of groupings within samples reflecting differences in morphological features. Here we propose the application of three custom-created modules to be used within the open-source software CellProfiler. These modules enable the automated detection of clusters present within the sample of microglia, as well as the assessment of the abundance of these clusters across conditions. The application of the analysis is conducted in a highly user-friendly manner, with a user interface integrated into the pipeline, enabling the performance of the analysis with only minimal user input. The workflow thereby includes the conduction of an outlier assessment, followed by hierarchical clustering and k-means clustering and the generation of interactive graphs to determine the number of microglia states present in the sample. Bar plots displaying the abundance of the microglia states across conditions included in the sample will be created. This approach will facilitate faster and more comparable detection of microglial morphological clusters across studies.

cell biology↗