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Ardalan, M.

Publications and source records attributed to Ardalan, M..

3 recordsLinked to original sources

A Novel Framework for Quantitative Analysis of Neuronal Primary Cilia in Brain Tissue

BackgroundAccurate analysis of neuronal primary cilia is essential for understanding developmental processing of neurons. But existing image segmentation methods struggle with staining variability and background noise. To address this, we developed a more robust segmentation and statistical analysis pipeline using an animal model small sample size and with known neuronal microstructure alterations. MethodsMaternal obesity was induced in mice via a high-fat/high-sucrose diet. Hippocampal tissue from 6-month-old offspring of obese and control dams was analyzed. We developed a MATLAB-based pipeline to segment neuronal cilia from z-stack images, applying mathematical transformations and using the Weibull distribution and Bayesian Information Criterion (BIC) to assess group differences ResultsThe technique segmented cilia despite artifacts, revealing group-specific patterns. Statistical analysis confirmed significant differences, highlighting the methods robustness over traditional tests, especially with small samples. ConclusionOur method reliably segments neuronal primary cilia in immune-stained sections with thionin-counter staining and offers a sensitive, assumption-free alternative to traditional statistical tests, ideal for small-sample neurobiological studies

neuroscience↗

Maternal n-3 enriched diet reprograms neurovascular transcriptome and blunts inflammation in neonate

Infection during perinatal period can adversely affect brain development, predispose infants to ischemic stroke and have lifelong consequences. We previously demonstrated that diet enriched in n-3 polyunsaturated fatty acids (PUFA) transforms brain lipid composition and protects from neonatal stroke. Vasculature is a critical interface between blood and brain providing a barrier to systemic infection. Here we examined whether maternal PUFA-enriched diets exert reprograming of endothelial cell signalling in 9-day old mice after endotoxin (LPS)-induced infection. Transcriptome analysis was performed on brain microvessels from pups born to dams maintained on 3 diets: standard, n-3 or n-6 enriched. N-3 diet enabled higher immune reactivity in brain vasculature, while preventing imbalance of cell cycle regulation and extracellular matrix cascades that accompanied inflammatory response in standard diet. LPS response in blood and brain was blunted in n-3 offspring. Cerebral angioarchitecture analysis revealed modified vessel complexity after LPS. Thus, n-3-enriched maternal diet partially prevents imbalance in homeostatic processes and alters inflammation rather than affects brain vascularization during early life. Importantly, maternal diet may presage offspring neurovascular outcomes later in life.

neuroscience↗

Transcriptome network analysis link perinatal Staphylococcus epidermidis infection to microglia reprogramming in the immature hippocampus

Staphylococcus epidermidis (S. epidermidis) is the most common nosocomial pathogen in preterm infants and associated with increased risk of cognitive delay, however, underlying mechanisms are unknown. We employed morphological, transcriptomic and physiological methods to extensively characterize microglia in the immature hippocampus following S. epidermidis infection. 3D morphological analysis revealed activation of microglia after S. epidermidis. Differential expression combined with network analysis identified NOD-receptor signalling and trans-endothelial leukocyte trafficking as major mechanisms in microglia. In support, active caspase-1 was increased in the hippocampus and using the LysM-eGFP knock-in transgenic mouse, we demonstrate infiltration of leukocytes to the brain together with disruption of the blood-brain barrier. Our findings identify activation of microglia inflammasome as a major mechanism underlying neuroinflammation following infection. The results demonstrate that neonatal S. epidermidis infection share analogies with S. aureus and neurological diseases, suggesting a previously unrecognized important role in neurodevelopmental disorders in preterm born children.

neuroscience↗