# Morphological and transcriptomic change of brain pericytes by lipopolysaccharide treatment

## TL;DR

This study shows that LPS treatment changes the shape and gene activity of brain pericytes, which could affect blood-brain barrier function and brain health.

## Contribution

The study reveals novel morphological and transcriptomic changes in brain pericytes induced by LPS, linking them to vascular and barrier function.

## Key findings

- LPS increases pericyte proliferation as shown by bromodeoxyuridine and Ki67 markers.
- LPS reduces pericyte cellular aspect ratio, indicating altered elongation.
- LPS alters gene expression related to proliferation, angiogenesis, and blood-brain barrier function.

## Abstract

Brain pericytes play essential roles in vascular homeostasis, including capillary stabilization and maintenance of the blood–brain barrier. Lipopolysaccharide (LPS), a component of the outer membrane of Gram-negative bacteria, is known to trigger inflammatory responses not only systemically but also within the central nervous system. In this study, we investigated the effects of LPS on the phenotype and transcriptome of brain vascular pericytes. LPS promoted bromodeoxyuridine incorporation in the primary culture of human brain pericytes as well as increased the number of Ki67-positive cells, indicating enhanced pericyte proliferation. Morphological analysis revealed that LPS decreased the cellular aspect ratio, suggesting altered cellular elongation. Transcriptomic profiling showed that LPS-induced differentially expressed genes were enriched for terms related to cell proliferation, angiogenesis, and blood–brain barrier function. Because pericytes critically regulate neurovascular coupling and metabolic support for active neurons, these LPS-induced alterations may ultimately perturb the microvascular control of neural circuits. These results suggest that LPS has the potential to regulate brain vascular function by inducing morphological and functional changes in pericytes.