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Aguayo, C.

Publications and source records attributed to Aguayo, C..

3 recordsLinked to original sources

Bioinformatic analysis of placental exomiRs targeting the brain in preeclampsia

BackgroundPreeclampsia is a hypertensive disorder of pregnancy associated with systemic endothelial dysfunction and, in severe cases, maternal neurological complications. Placenta-derived exosomal microRNAs (exomiRs) mediate inter-organ communication and may contribute to neurovascular injury, but their role in maternal brain dysregulation remains unclear. MethodsWe performed systems-level bioinformatic analyses of 12 differentially expressed exomiRs (6 from early-onset and 6 from late-onset preeclampsia) to assess their potential impact on brain homeostasis. Target interactomes were examined for functional enrichment, subcellular localization, and network complexity. ExomiR targets were integrated with cerebrospinal fluid (CSF) proteomic profiles from preeclamptic women with neurological symptoms. We further evaluated regulation of blood-brain barrier (BBB) components and mapped spatial expression of target proteins across brain regions and cell types relevant to neurovascular function. ResultsEarly-and late-onset preeclampsia exomiRs displayed distinct interactomes and biological signatures. Early-onset exomiRs were linked to RNA metabolism, oxidative stress, and endothelial stability, whereas late-onset exomiRs were enriched in nitrogen metabolism and vesicle-mediated transport. Integration with CSF proteomics revealed convergence on dysregulated proteins, including MAPK8, RTN4, and YWHA family members, involved in inflammation, neurodegeneration, and axonal inhibition. Several exomiRs targeted BBB-related proteins (CLDN2, TJP1, EFNA5), suggesting coordinated barrier disruption. Spatial mapping localized these targets to endothelial cells, astrocytes, interneurons, and pyramidal neurons, implicating altered synaptic and glial regulation. ConclusionsPreeclampsia-associated exomiRs may impair maternal brain homeostasis through coordinated regulation of neurovascular, inflammatory, and synaptic pathways. These findings identify candidate molecular mediators of preeclampsia-related neurovascular dysfunction and potential biomarkers for maternal brain injury.

physiology↗

Cross-species transmission and PB2 mammalian adaptations of highly pathogenic avian influenza A/H5N1 viruses in Chile

H5N1 highly pathogenic avian influenza viruses (HPAIV) emerged in wild birds in Chile in December 2022 and spilled over into poultry, marine mammals, and one human. Between December 9, 2022 - March 14, 2023, a coordinated government/academic response detected HPAIV by real-time RT-PCR in 8.5% (412/4735) of samples from 23 avian and 3 mammal orders. Whole-genome sequences obtained from 77 birds and 8 marine mammals revealed that all Chilean H5N1 viruses belong to lineage 2.3.4.4b and cluster monophyletically with viruses from Peru, indicating a single introduction from North America into Peru/Chile. Mammalian adaptations were identified in the PB2 segment: D701N in two sea lions, one human, and one shorebird, and Q591K in the human and one sea lion. Minor variant analysis revealed that D701N was present in 52.9 - 70.9% of sequence reads, indicating the presence of both genotypes within hosts. Further surveillance of spillover events is warranted to assess the emergence and potential onward transmission of mammalian adapted H5N1 HPAIV in South America.

microbiology↗