Micro-anatomic alterations of the placenta in a non-human primate model of gestational protein-restriction

Abstract

Objectives Maternal protein malnutrition is associated with impaired fetal growth, and lifetime consequences for the offspring. Our group has previously developed a model of protein-restriction in the non-human primate, which was associated with fetal growth restriction, stillbirth, decreased placental perfusion, and evidence of fetal hypoxia, suggesting perturbed vascular development. Our objective was to histologically characterize the micro-anatomic alterations associated with adverse pregnancy outcomes taking an approach that permits investigation of the 3D vascular structure and surrounding histology without the requirement for 3D vascular casting or relying on 2D stereology which both have methodological limitations. Methods Rhesus macaques were assigned in the pre-gestational period to a control diet that contained 26% protein, or study diet containing 13% protein (50% PR diet). Placental tissue was collected at delivery and processed using a clarification, immunohistochemistry, and confocal microscopy protocol published previously by our group. Three dimensional reconstructions and quantitative assessment of the vascular micro-anatomy was performed using analysis software (Imaris ®) and statistical analysis accounted for maternal and fetal confounders. Results In unadjusted analysis, when comparing those pregnancies on a 50% PR diet (n = 4) with those on a control diet (n = 4), protein-restriction diet was associated with decreased maternal pre-pregnancy weight (difference of-1.975kg, 95% CI-3.267 to-0.6826). When controlling for maternal pre-pregnancy weight, fetal sex, and latency from tissue collection to

Three-dimensional visualization of cerebral blood vessels and neural changes in thick ischemic rat brain slices using tissue clearing

“…All parameters were measured in multiple ROIs (3–4 ROIs/each) in the ipsilateral cortex and striatum, where the vascular fluorescence intensity decreased rapidly near the infarcted border compared with the symmetrical lateral cortex and striatum. Quantitative analysis of blood vessels was performed as previously described 49 . Quantitative evaluation of vessel length and diameter was performed in maximum intensity projection mode with rendering quality set to 100%.…”