Biology subjects

Vatish, M.

Publications and source records attributed to Vatish, M..

8 recordsLinked to original sources

bioRxiv2025

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↗

bioRxiv2025

Sex-Specific Neurovascular and Cognitive Deficits in Offspring of Preeclampsia

BackgroundOffspring of preeclampsia may develop long-term neurovascular and cognitive impairments, but the underlying mechanisms remain unclear. We investigate sex-specific alterations in brain vascular function and cognition in a murine model of preeclampsia induced by the nitric oxide synthase inhibitor L-NAME. MethodsPregnant mice received L-NAME (gestational day 7 to 19). Offspring were assessed at postnatal day 5 (P5) and in adulthood (4-5 months). Brain vascular development, angiogenesis, perfusion, cold-induced vasoconstriction, and blood-brain barrier (BBB) integrity were assessed in vivo and ex vivo. Offsprings serum was applied to brain endothelial cell cultures to evaluate endothelial activation and barrier function. Adult cognitive performance was evaluated through behavioral tests and hippocampal long-term potentiation (LTP) recordings. ResultsL-NAME offspring (P5) exhibited reduced brain vascular density, decreased tip cell formation, and impaired cold-induced vasoconstriction, most prominently in males. BBB integrity was compromised, with increased permeability and reduced expression of tight junction proteins (claudin-5, ZO-1), again more pronounced in males. Serum from L-NAME offspring induced endothelial activation and barrier dysfunction in vitro. These effects were accompanied by increased brain and systemic levels of hypoxia markers and proinflammatory cytokines (IL-6, TNF-). Adult L-NAME offspring showed cognitive deficits in recognition and spatial memory tasks, with female offspring displaying more pronounced impairments. These behavioral findings paralleled a reduced magnitude and impaired stabilization of hippocampal LTP in females. ConclusionsPrenatal exposure to a preeclampsia-like environment induces persistent, sex-specific neurovascular and cognitive deficits in offspring. These findings underscore the need for long-term neurological follow-up in children born to preeclamptic pregnancies.

physiology↗

bioRxiv2025

Plasma, not extracellular vesicles, disrupts the blood-brain barrier in eclampsia.

BackgroundEclampsia is a severe complication of preeclampsia involving blood-brain barrier (BBB) disruption. While small extracellular vesicles (sEVs) contribute to endothelial dysfunction in preeclampsia, their role in eclampsia remains unclear. Magnesium sulfate (MgSO), the standard treatment, may mitigate BBB injury. We examined the effects of plasma and plasma-derived sEVs from women with eclampsia on BBB integrity and the potential modulatory role of MgSO. MethodsPlasma and plasma-sEVs were isolated from women with normotensive pregnancies (n=18), preeclampsia (n=19), preeclampsia with organ complications (n=17), and eclampsia (n=20). An in vitro BBB model based on the culture of human brain endothelial cells was used to evaluate electrical resistance (TEER), Dextran 70 kDa permeability, and cytoskeletal alterations in the presence of womens plasmas or plasma-sEVs. The uptake of fluorescently labeled sEVs in the absence or pretreatment (-3 h) with MgSO, and sEVs cargo of relevant proteins involved in BBB regulation, were analyzed. ResultsPlasma from women with eclampsia disrupted the BBB, with marked reductions in TEER and increased permeability compared to normotensive controls, preeclampsia, and preeclampsia with organ complications. In contrast, plasma-sEVs of women with eclampsia caused less BBB impairment than plasma-sEVs from normotensive controls or preeclampsia, correlating with reduced sEVs uptake by brain endothelial cells. Lower levels of eNOS and TNF- in eclampsia-derived sEVs compared to normotensive controls were founnd. MgSO treatment further diminished sEVs uptake. ConclusionsPlasma, rather than sEVs, appears to drive BBB disruption in eclampsia. MgSO may influence these effects by reducing sEVs uptake and altering their protein cargo.

physiology↗

bioRxiv2024

hsa-miR-9-5p highly expressed in syncytiotrophoblast-derived extracellular vesicles from early-onset preeclampsia impairs cerebral microvascular endothelial cell pro-angiogenic capacity

BackgroundCerebrovascular complications are the leading cause of maternal mortality associated with preeclampsia. Extracellular vesicles (EVs) containing microRNAs (miRNAs) and derived from syncytiotrophoblast (STB-EVs) are suspected to play a role in these complications. Previously, we found that STB-EVs from the placentas of women with preeclampsia have a higher content of the angiogenesis regulator hsa-miR-9-5p. We now investigate the effects of hsa-miR-9-5p on the proangiogenic properties of brain endothelial cells and identify potential protein targets involved in these processes. MethodsBrain endothelial cells (hCMEC/D3) were treated with hsa-miR-9-5p (0, 5 and 10 nM) to assess cell viability and proliferation. Additionally, cell migration and proteomic profile in hCMEC/D3 treated with hsa-miR-9-5p (10 nM) were also analyzed. ResultsCompared to control, hsa-miR-9-5p significantly reduced hCMEC/D3 cell proliferation and migration without affecting cell viability. Proteomic analysis identified several vital proteins potentially mediating these effects, including vascular endothelial growth factor type C (VEGFC), placental growth factor (PLGF or PGF), and platelet-derived growth factor B (PDGFB). Treatment with hsa-miR-9-5p did not impair the capacity of hCMEC/D3 to respond to tumour necrosis factor- (TNF-). Conclusionhsa-miR-9-5p reduces hCMEC/D3 cell proliferation and migration, and modulates the expression of angiogenic regulators such as VEGFC, PLGF, and PDGFB, without affecting TNF- mediated activation of hCMEC/D3. This suggests that STB-EVs cargo hsa-miR-9-5p may selectively inhibit the proangiogenic capacity of brain endothelial cells. These findings enhance our understanding of cerebrovascular alterations in preeclampsia and may guide future studies and therapeutic interventions.

physiology↗

bioRxiv2024

Extracellular vesicles from preeclampsia disrupt the blood-brain barrier via reduced claudin-5: potential role of vascular endothelial growth factor

BackgroundPhysiopathology of life-treating cerebrovascular complications in preeclampsia are yet unknown. We investigated whether disruption of the blood-brain barrier (BBB), generated using circulating small extracellular vesicles (sEVs) from women with preeclampsia or placentae cultured under hypoxic conditions, impairs the expression of tight junction proteins, such as claudin 5 (CLDN5), mediated by VEGF and activation of VEGF receptor 2 (KDR). MethodssEVs were isolated from plasma (normal pregnancy, sEVs-NP, n=9); preeclampsia, sEVs-PE, n=9) or placental explants from normotensive pregnancies, cultured in normoxia (sEVs-Nor, n=10) or hypoxia (sEVs-Hyp, n=10). The integrity of the BBB was evaluated using in vitro (human and mice brain endothelial cell lines) and in vivo (non-pregnant C57BL/6 mice (4 to 5 months old, (n=10) were injected with sEVs-Hyp), models. ResultssEVs-PE and sEVs-Hyp reduced CLND5 levels (p<0.05) in the endothelial cell membrane without affecting other tight junction proteins. These results were negated with sEVs-PE sonication. sEVs-Hyp injected into non-pregnant mice generated neurological deficits and BBB disruption, specifically in the posterior area of the brain, associated with reduction in CLND5 levels in the brain cortex. Furthermore, sEVs-PE and sEVs-sHyp had higher VEGF levels than sEVs-NP and sEVs-Nor, respectively. Human brain endothelial cells exposed to sEVs-PE or sEVs-sHyp exhibited a reduction in the activation of KDR. ConclusionsEVs from hypoxic placentae and plasma from women with preeclampsia disrupt the BBB, via reduction of CLDN5, a phenomenon that may involve VEGF contained within these vesicles. These findings will improve the elucidation of cerebrovascular alterations in women with preeclampsia.

physiology↗

bioRxiv2023

Syncytiotrophoblast 5'-tRNA fragments are placental endocrine signals contributing to sterile inflammation in preeclampsia

BackgroundThe relationship between placental pathology and the maternal syndrome of preeclampsia is incompletely characterised. Mismatch between placental nutrient supply and fetal demands induces stress in the syncytiotrophoblast, the layer of placenta in direct contact with maternal blood. Such stress alters the content and increases the release of extracellular vesicles (STB-EVs) into the maternal circulation. We have previously shown 5-tRNA fragments (5-tRFs) constitute the majority of small RNA in STB-EVs in healthy pregnancy. 5-tRFs are produced in response to stress. We hypothesised STB-EV 5-tRF release might change in preeclampsia. MethodsWe perfused placentas from eight women with early-onset preeclampsia and six controls, comparing small RNA expression in STB-EVs. We used membrane-affinity columns to isolate maternal plasma vesicles and investigate placental 5-tRFs in-vivo. We quantified 5-tRFs from circulating STB-EVs using a placental alkaline phosphatase immunoassay. 5-tRFs and scrambled RNA controls were added to monocyte, macrophage and endothelial cells in culture to investigate transcriptional responses. Results5-tRFs constitute the majority of small RNA in STB-EVs from both preeclampsia and normal pregnancies. >900 small RNA fragments are differentially expressed in preeclampsia STB-EVs. Preeclampsia-dysregulated 5-tRFs are detectable in maternal plasma, where we identified a placentally-derived load. 5-tRF-Glu-CTC, the most abundant preeclampsia-upregulated 5-tRF in perfusion STB-EVs, is also increased in preeclampsia STB-EVs from maternal plasma. 5-tRF-Glu-CTC induced inflammation in macrophages but not monocytes. The conditioned media from 5-tRF-Glu-CTC-activated macrophages reduced eNOS expression in endothelial cells. ConclusionsIncreased release of syncytiotrophoblast-derived vesicle-bound 5-tRF-Glu-CTC contributes to preeclampsia pathophysiology.

molecular biology↗

bioRxiv2019

Maternal circulating syncytiotrophoblast-derived extracellular vesicles contain biologically active 5’-tRNA halves

The placenta releases syncytiotrophoblast-derived extracellular vesicles (STB-EV) into the maternal circulation throughout gestation. STB-EV dependent signalling is believed to contribute to the widespread maternal adaptive physiological changes seen in pregnancy. Transfer RNA (tRNA) halves have been identified in vesicles released from other human and murine organ systems, which alter gene expression in target cells. Here, we characterise tRNA-half expression in STB-EV and demonstrate biological activity of a highly abundant tRNA-half. Short RNA from ex-vivo, dual-lobe placental perfusion STB-EV was sequenced, showing that most (>95%) comprised tRNA species. Whole placental tissue contained <50% tRNA species, suggesting selective packaging and export of tRNA into STB-EV. Most tRNA within STB-EV were 5-tRNA halves cleaved at 30-32 nucleotides. The pattern of tRNA expression differed depending on the size/origin of the STB-EV; this was confirmed by qPCR. Protein synthesis was suppressed in human fibroblasts when they were cultured with a 5-tRNA half identified from STB-EV sequencing. This study is the first to evaluate tRNA species in STB-EV. The presence of biologically active 5-tRNA halves, specific to a vesicular origin, suggests a novel mechanism for maternal-fetal signalling in normal pregnancy.

physiology↗

bioRxiv2017

Differential activation of Fyn kinase distinguishes saturated and unsaturated fats in mouse macrophages

Diet-induced obesity is associated with increased adipose tissue activated macrophage numbers. Yet, how macrophages integrate fatty acid (FA) signals remains unclear. We previously demonstrated that Fyn deficiency (FynKO) protects against high fat diet-induced adipose tissue macrophage accumulation. Herein, we show that inflammatory markers and reactive oxygen species are not induced in FynKO bone marrow-derived macrophages exposed to the saturated FA palmitate, suggesting that Fyn regulates macrophage function in response to FA signals. Saturated palmitate activates Fyn and re-localizes Fyn into the nucleus of RAW264.7, J774 and wild-type bone marrow-derived macrophages. Similarly, Fyn activity is increased in cells of AT stromal vascular fraction of high fat-fed control mice, with Fyn protein being located in the nucleus of these cells. We demonstrate that Fyn modulates palmitate-dependent oxidative stress in macrophages. Moreover, Fyn catalytic activity is necessary for its nuclear re-localization and downstream effects, as Fyn pharmacological inhibition abolishes palmitate-induced Fyn nuclear redistribution and palmitate-dependent increase of oxidative stress markers. Importantly, mono-or polyunsaturated FAs do not activate Fyn, and fail to re-localize Fyn to the nucleus. Together these data demonstrate that macrophages integrate nutritional FA signals via a differential activation of Fyn that distinguishes, at least partly, the effects of saturated versus unsaturated fats.

cell biology↗