{
  "abstract": "Rationale Pulmonary arterial hypertension (PAH) is a progressive, fatal cardiovascular that develops as a result of elevated pressure and vascular remodelling within the pulmonary arteries (1). The pathobiology of PAH is driven by several factors, such as vasoconstriction, abnormal cellular proliferation, reduction of apoptosis, fibrosis, in situ thrombosis, and inflammation affecting small and muscular pulmonary arteries (2). Aberrant TGF-β and BMP signalling pathways serve as the primary mechanism contributing to the development and progression of PAH. Mutations in the type II receptor for bone morphogenetic protein (BMPR-II) account for approximately 80% of heritable cases (3), emphasising the critical role of BMP signalling. Despite these insights, the pathogenesis is incompletely understood. Current therapies were initially developed based on early identification of dysregulated vasoactive pathways that directly regulate pulmonary vascular tone. However, treatments only manage symptoms and do not reverse vascular remodelling. Emerging evident suggests additional genes including ACVRL1 and KCNK3 (4) contribute to disease pathogenesis, highlighting the complexity of PAH and the need to uncover novel molecular mechanism. This study aims to investigate how specific genes modulate canonical TGF-β/BMP signalling in PAH.Methods To achieve these aims, a series of cell-based assays were performed in HEK293T cells, including SMAD-responsive luciferase reporter assays to assess TGF-β and BMP pathway activity following overexpression of relevant receptors, SMADs, and ligands. Gene expression analyses were conducted using qPCR and RT-PCR, while protein expression and pathway activation were assessed by Western blotting. Luciferase activity and gene expression data were normalised to appropriate internal controls, and protein levels were quantified by densitometric analysis. Statistical analyses were performed to evaluate differences between experimental conditions.Results Initial screening using SMAD-responsive luciferase assays in HEK293T cells identified a panel of genes that consistently inhibited TGF-β signalling, whilst having no discernible effect on BMP signalling. In parallel, candidate genes were investigated for their regulatory roles on TGF-β and BMP signalling. Preliminary SMAD-responsive luciferase assays identified a number of genes which selectively inhibited either BMP or promoted TGF-β signalling pathway. These findings are currently being further validated using independent techniques including qPCR, RT-PCR and western blotting.Conclusion These findings reveal candidate genes, capable of modulating TGF- β and BMP signalling thereby restoring cellular defects such as excessive proliferation and reduction of apoptosis. Taken together, this study clarifies the underlying molecular mechanisms and uncovers novel additional targets, which may be explored for developing novel diagnostics and therapeutics.",
  "authors": [
    {
      "affiliations": [
        "University of Bradford, Bradford, United Kingdom"
      ],
      "name": "Aneesa Ahmed"
    },
    {
      "affiliations": [
        "University of Bradford, Bradford, United Kingdom"
      ],
      "name": "Talat Nasim"
    },
    {
      "affiliations": [
        "University of Bradford, Bradford, United Kingdom"
      ],
      "name": "Colin Wright"
    }
  ],
  "title": "202 Identification of novel regulators of SMAD-dependent signalling in pulmonary arterial hypertension (PAH)",
  "uid": "57f0b68b-bd03-5a96-85a3-b2532c1e4f06"
}