Project description:This article is based on the address given by the author at the 2020 virtual meeting of the American Society of Human Genetics (ASHG) on October 26, 2020. The video of the original address can be found at the ASHG website.
Project description:Molecules has started to institute a "Best Paper" award to recognize the most outstanding papers in the area of natural products, medicinal chemistry and molecular diversity published in Molecules. We are pleased to announce the second "Molecules Best Paper Award" for 2013.
Project description:Marfan syndrome (MFS) is an autosomal dominant, age-related but highly penetrant condition with substantial intrafamilial and interfamilial variability. MFS is caused by pathogenetic variants in FBN1, which encodes fibrillin-1, a major structural component of the extracellular matrix that provides support to connective tissues, particularly in arteries, the pericondrium and structures in the eye. Up to 25% of individuals with MFS have de novo variants. The most prominent manifestations of MFS are asymptomatic aortic root aneurysms, aortic dissections, dislocation of the ocular lens (ectopia lentis) and skeletal abnormalities that are characterized by overgrowth of the long bones. MFS is diagnosed based on the Ghent II nosology; genetic testing confirming the presence of a FBN1 pathogenetic variant is not always required for diagnosis but can help distinguish MFS from other heritable thoracic aortic disease syndromes that can present with skeletal features similar to those in MFS. Untreated aortic root aneurysms can progress to life-threatening acute aortic dissections. Management of MFS requires medical therapy to slow the rate of growth of aneurysms and decrease the risk of dissection. Routine surveillance with imaging techniques such as transthoracic echocardiography, CT or MRI is necessary to monitor aneurysm growth and determine when to perform prophylactic repair surgery to prevent an acute aortic dissection.
Project description:Comparison of whole genome expression profiles to characterize gene expression during development of thoracic aortic aneurysm in fibrillin-1 hypomorphic mice (Fbn1mgR/mgR).
Project description:Marfan syndrome (MFS), a relatively common autosomal dominant hereditary disorder of connective tissue with prominent manifestations in the skeletal, ocular, and cardiovascular systems, is caused by mutations in the glycoprotein gene fibrillin-1 (FBN1). Aortic root dilation and mitral valve prolapse are the main presentations among the cardiovascular malformations of MFS. The revised Ghent diagnostics nosology of Marfan syndrome is established in accordance with a combination of major and minor clinical manifestations in various organ systems and the family history. The pathogenesis of Marfan syndrome has not been fully elucidated. However, fibrillin-1 gene mutations are believed to exert a dominant negative effect. The treatment includes prophylactic β-blockers and angiotensin II-receptor blockers in order to slow down the dilation of the ascending aorta and prophylactic aortic surgery. Importantly, β-blocker therapy may reduce TGF-β activation, which has been recognized as a contributory factor in MFS. The identification of a mutation allows for early diagnosis, prognosis, genetic counseling, preventive management of carriers and reassurance for unaffected relatives. The importance of knowing in advance the location of the putative family mutation is highlighted by its straightforward application to prenatal and postnatal screening. The present article aims to provide an overview of this rare hereditary disorder.
Project description:Marfan syndrome (MFS) is a pleiotropic connective tissue disease inherited as an autosomal dominant trait, due to mutations in the FBN1 gene encoding fibrillin 1. It is an important protein of the extracellular matrix that contributes to the final structure of a microfibril. Few cases displaying an autosomal recessive transmission are reported in the world. The FBN1 gene, which is made of 66 exons, is located on chromosome 15q21.1. This review, after an introduction on the clinical manifestations that leads to the diagnosis of MFS, focuses on cardiovascular manifestations, pharmacological and surgical therapies of thoracic aortic aneurysm and/or dissection (TAAD), mechanisms underlying the progression of aneurysm or of acute dissection, and biomarkers associated with progression of TAADs. A Dutch group compared treatment with losartan, an angiotensin II receptor-1 blocker, vs no other additional treatment (COMPARE clinical trial). They observed that losartan reduces the aortic dilatation rate in patients with Marfan syndrome. Later on, they also reported that losartan exerts a beneficial effect on patients with Marfan syndrome carrying an FBN1 mutation that causes haploinsufficiency (quantitative mutation), while it has no significant effect on patients displaying dominant negative (qualitative) mutations. Moreover, a French group in a 3-year trial compared the administration of losartan vs placebo in patients with Marfan syndrome under treatment with beta-receptor blockers. They observed that losartan decreases blood pressure but has no effect on aortic diameter progression. Thus, beta-receptor blockers remain the gold standard therapy in patients with Marfan syndrome. Three potential biochemical markers are mentioned in this review: total homocysteine, serum transforming growth factor beta, and lysyl oxidase. Moreover, markers of oxidative stress measured in plasma, previously correlated with clinical features of Marfan syndrome, may be explored as potential biomarkers of clinical severity.
Project description:Marfan syndrome (MFS) is a connective tissue disorder caused by mutations in the fibrillin-1 (Fbn1) gene. While aortic rupture is the major cause of mortality in MFS, patients also suffer from poorly understood pulmonary complications. Loss of basal nitric oxide (NO) production and vascular integrity are proposed to take part in MFS aortic root disease, yet their contribution to lung complications has yet to be determined. Due to its capacity to potentiate the vasodilatory NO/cyclic guanylate monophosphate signaling pathway, we assessed whether the phosphodiesterase-5 (PDE5) inhibitor sildenafil (SIL) could attenuate aortic root remodelling and emphysema in a mouse model of MFS. Despite increasing NO-dependent vasodilation, SIL unexpectedly elevated mean arterial blood pressure, failed to inhibit MFS aortic root dilation and exacerbated elastic fibrefiber fragmentation. In the lung, early pulmonary artery dilation observed in untreated MFS mice was delayed by SIL treatment, and severe emphysema-like alveolar destruction was prevented. In addition, improvements in select parameters of lung function were documented. Subsequent micro-array analyses showed changes to gene signatures involved in the inflammatory response in MFS lung treated with SIL, without significant downregulation of connective tissue or TGF-β signalling genes. Since PDE5 inhibition leads to improved lung histopathology and function, the effects of SIL against emphysema warrant further investigation in the settings of MFS despite limited efficacy on aortic root remodelling.