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Ek, J.

Publications and source records attributed to Ek, J..

3 recordsLinked to original sources

Hypoadiponectinemia does not enhance anxiety-like behaviour in a lean PCOS-like mouse model

Polycystic ovary syndrome (PCOS) is characterized by reproductive and metabolic disturbances and is associated with increased symptoms of anxiety and depression. Circulating adiponectin, an insulin-sensitizing adipokine, is reduced in women with PCOS, and low adiponectin has been linked to impaired mental health, particularly in females. We investigated whether low serum adiponectin is associated with impaired mental health in women with PCOS and whether adiponectin deficiency exacerbates anxiety-like behaviour in a PCOS-like mouse model. Serum adiponectin was measured in women with (n=179) and without PCOS (n=228), stratified by body mass index (BMI). Health-related quality of life was assessed using the SF-36, generating physical and mental component scores. In parallel, the prenatal androgenization (PNA) PCOS-like mouse model was combined with adiponectin-deficient mice (APNhet) to assess the impact of reduced adiponectin on anxiety-like behaviour with and without prenatal androgen exposure. Women with PCOS had lower total and high molecular weight adiponectin levels compared with controls. Adiponectin positively correlated with mental component scores in women with BMI <30, but not in those with obesity. Free testosterone was inversely correlated with adiponectin. In mice, PNA induced anxiety-like behaviour, however, reduced adiponectin did not exacerbate this phenotype. Although APNhet PNA mice showed 65% lower serum adiponectin levels and reproductive dysfunction, they displayed improved metabolic function. Unlike women with PCOS, adult PNA mice were not hyperandrogenic. These findings suggest that adiponectin is associated with mental health in non-obese women, but reduced adiponectin alone does not induce anxiety-like behaviour in the absence of hyperandrogenism. The differing patterns observed across BMI categories, as well as between the human cohort and experimental data, underscore the complexity of the mechanisms underlying mental health disturbances in PCOS.

animal behavior and cognition↗

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↗