Biology subjects

Westergren-Thorsson, G.

Publications and source records attributed to Westergren-Thorsson, G..

4 recordsLinked to original sources

bioRxiv2026

Altered cellular VEGF dynamics in Chronic Obstructive Pulmonary Disease

Pulmonary vascular remodelling is common in patients with chronic obstructive pulmonary disease (COPD). Vascular endothelial growth factors (VEGFs) are key mediators in angiogenesis and vascular remodelling and exist in different isoforms. VEGF-A is the most potent angiogenic member binding to VEGF receptor 2 (VEGFR2). There are, however, few studies on other isoforms, as VEGF-C, and its receptor VEGFR3 in COPD and subsequent impact of cAMP therapies on VEGF isoforms. Our aim was to evaluate the VEGF isoform synthesis in primary distal lung fibroblasts from control subjects (non-smokers (n=6) and ex-smokers (n=4), and COPD subjects with GOLD stage II (n=4) or GOLD stage IV (n=6), and the expression of VEGFR2 and VEGFR3 in human lung tissue. Primary lung fibroblasts were exposed to the cAMP generating therapies formoterol, iloprost, or roflumilast, the adenylyl cyclase activator forskolin or to transforming growth factor (TGF)-b1. VEGF isoforms were evaluated with ELISA. VEGF-C release was not significantly altered by TGF-{beta}1, in contrast to the increased levels of VEGF-A, in all fibroblasts. VEGF-C was significantly decreased by iloprost, forskolin and formoterol, whereas VEGF-A was significantly increased by iloprost and forskolin, with differences in release pattern between and within fibroblasts from control and COPD subjects. Exposure to VEGF-C specifically towards VEGFR3 decreased proliferative rate in human lung fibroblasts and bronchial epithelial cells. VEGFR2 and VEGFR3 were both present in parenchymal lung tissue and VEGFR2 in pulmonary blood vessels. in both healthy and COPD, whereas there was elevated expression of VEGFR3 in bronchial epithelium. In conclusion, TGF-{beta}1 and cAMP generating compounds have significant effects on VEGF-C and VEGF-A synthesis, which appear dysregulated in lung fibroblasts from ex-smokers and patients with COPD. Increased VEGFR3 expression in the bronchial epithelium in lung tissue, and studies into their functional impact, warrants further investigations.

pathology↗

bioRxiv2025

Transcriptional Roadmap of the Human Airway Epithelium Identifying HLF as a Novel Regulator of Basal Stem Cell Function

RationaleThe human airway epithelium depends on a coordinated hierarchy of stem-and differentiated cells to maintain tissue integrity and respond to injury. Defining the transcriptional and translational programs that govern these processes is critical for understanding airway disease and advancing regenerative therapies. ObjectivesTo map the transcriptional landscape of the human airway epithelium and identify regulatory factors controlling basal stem cell function and epithelial differentiation. MethodsWe performed single-cell RNA sequencing on bronchial biopsies from nine healthy never-smokers, categorized into young (<40 years) and aged (>60 years) cohorts. Unbiased cell type annotation and pseudotime trajectory analysis were used to define cell states and transcription factor dynamics. Measurements and Main ResultsAll major airway epithelial cell types were identified, with conserved composition and transcriptional programs across age groups. Basal stem cells (BSCs) exhibited elevated ribosomal gene expression, indicating increased translational readiness. Pseudotime analysis revealed transitions from basal to differentiated states, with MYC, JUN, and FOS upregulated in proliferative suprabasal cells. HLF emerged as a BSC-enriched transcription factor downregulated upon differentiation. Functional assays showed that HLF overexpression suppresses proliferation in airway BSC and in lung squamous carcinoma cells, while Hlf-deficient mice display basal cell hyperplasia and deficient differentiation. In lung cancer datasets, low HLF expression correlated with worse patient survival. ConclusionsThis study defines conserved gene programs in the human airway epithelium and identifies HLF as a novel regulator of BSC proliferation and potential tumor suppressor. These findings may inform the development of regenerative therapies and contribute to improved understanding and treatment of lung disease.

molecular biology↗

bioRxiv2023

Maternal sterol 27-hydroxylase is crucial for securing fetal development

The maternal body helps in providing nutrients and degrading toxic metabolites instead of the fetal body; disruptions in these mechanisms affect normal fetal development. Sterol 27-hydroxylase (Cyp27a1) is involved in the alternative pathway of bile acid synthesis, which is enhanced during pregnancy. However, its role in fetal development remains unclear. Here, we demonstrate that maternal Cyp27a1 activity is essential for progression of normal pregnancy and fetal organ formation. Depletion of maternal Cyp27a1 reduced the pregnancy rate and litter size. Newborn mice died of respiratory distress syndrome resulting from the absence of mature alveolar epithelial cells. These phenotypes were caused by 7-hydroxycholesterol (7-HC) accumulating in Cyp27a1-deficient mice. Mechanistically, 7-HC destabilized the Fau protein, mediating ribosome assembly, the downregulation of which caused poor polysome formation, lower protein synthesis, and impaired lung maturation. Overall, this study revealed an essential mechanism of securing fetal development by degrading a toxic metabolite in the maternal body.

developmental biology↗

bioRxiv2023

Proteomic analysis across patient iPSC-based models and human post-mortem hippocampal tissue reveals early cellular dysfunction, progression, and prion-like spread of Alzheimer s disease pathogenesis

The hippocampus is a primary region affected in Alzheimers disease (AD). Because AD postmortem brain tissue is not available prior to symptomatic stage, we lack understanding of early cellular pathogenic mechanisms. To address this issue, we examined the cellular origin and progression of AD pathogenesis in patient-based model systems including iPSC-derived brain cells transplanted into the mouse brain hippocampus. Notably, proteomic analysis of the graft enabled the identification of proteomic alterations in AD patient brain cells, associated with increased levels of {beta}-sheet structures and A{beta}42 peptides. Interestingly, the host cells surrounding the AD graft also presented alterations in cellular biological pathways. Furthermore, proteomic analysis across human iPSC-based models and human post-mortem hippocampal tissue projected coherent longitudinal cellular changes indicative of disease progression from early to end stage AD. Our data showcase patient-based models to study the cellular origin, progression, and prion-like spread of AD pathogenesis. Highlights- AD patient iPSC-derived brain cells survive in the hippocampus of immunodeficient mice 6 months post-transplantation. - Proteomic analysis of the grafts reveals profound alterations in cellular biological pathways in iPSC-derived hippocampal cells despite absence of senile plaques. - Proteomic alterations within transplanted AD iPSC-derived hippocampal cells are reminiscent of early/prodromal AD. - AD-grafted cells induce proteomic changes in host mouse cells.

neuroscience↗