Biomarkers of Aortopathy in Marfan Syndrome

Targeted proteomics and metabolomics for biomarker discovery in abdominal aortic aneurysm and post-EVAR sac volume

BACKGROUND AND AIMS

Abdominal aortic aneurysm (AAA) patients undergo uniform surveillance programs both leading up to, and following surgery. Circulating biomarkers could play a pivotal role in individualizing surveillance. We applied a multi-omics approach to identify relevant biomarkers and gain pathophysiological insights.

MATERIALS AND METHODS

In this cross-sectional study, 108 AAA patients and 200 post-endovascular aneurysm repair (post-EVAR) patients were separately investigated. We performed partial least squares regression and ingenuity pathway analysis on circulating concentrations of 96 proteins (92 Olink Cardiovascular-III panel, 4 ELISA-assays) and 199 metabolites (measured by LC-TQMS), and their associations with CT-based AAA/sac volume.

RESULTS

The median (25th-75th percentile) maximal diameter was 50.0 mm (46.0, 53.0) in the AAA group, and 55.4 mm (45.0, 64.2) in the post-EVAR group. Correcting for clinical characteristics in AAA patients, the aneurysm volume Z-score differed 0.068 (95 %CI: (0.042, 0.093)), 0.066 (0.047, 0.085) and -0.051 (-0.064, -0.038) per Z-score valine, leucine and uPA, respectively. After correcting for clinical characteristics and orthogonalization in the post-EVAR group, the sac volume Z-score differed 0.049 (0.034, 0.063) per Z-score TIMP-4, -0.050 (-0.064, -0.037) per Z-score LDL-receptor, -0.051 (-0.062, -0.040) per Z-score 1-OG/2-OG and -0.056 (-0.066, -0.045) per Z-score 1-LG/2-LG.

CONCLUSIONS

The branched-chain amino acids and uPA were related to AAA volume. For post-EVAR patients, LDL-receptor, monoacylglycerols and TIMP-4 are potential biomarkers for sac volume. Additionally, distinct markers for sac change were identified.

Silent Type-B Aortic Dissection Accidentally Discovered in a COVID-19-Positive Patient

Aortic dissection is a critical medical condition that poses a significant threat to life, and if left untreated, it can lead to high mortality and morbidity rates. The risk of various cardiovascular complications, including aortic dissection, is increased in individuals with coronavirus disease 2019 (COVID-19). However, the significance of aortic dissection as a complication in COVID-19 patients is often underestimated. Traditionally, aortic dissection without pain was considered uncommon. However, recent information indicates that symptoms in patients with aortic dissection can be more diverse than previously believed. The classic symptoms of tearing chest, back, or abdominal pain may be absent, making diagnosis challenging. We present the incidental detection of an asymptomatic Stanford type-B aortic dissection during a computed tomography (CT) scan conducted to evaluate COVID-19. The patient was managed through conservative treatment.

Aortic dissection and Covid-19; a comprehensive systematic review

Coronavirus disease 19 (Covid-19) has been declared as a pandemic disease since March 2020; causing wide array of signs and symptoms, many of which result in increased mortality rates worldwide. Although it was initially known as an acute respiratory disease, Covid-19 is accompanied with several extrapulmonary manifestations, of which the cardiovascular ones are of major importance. Among other cardiovascular complications of Covid-19, aortic dissection has been a significant yet underrated problem. The pathophysiology of aortic dissection consists of various inflammatory pathways, that could be influenced by Covid-19 infection. We herein have reviewed articles inclusive of aortic dissection concurrent with Covid-19 infection in a systematic manner, along with the probable similarities in pathophysiology of aortic dissection with Covid-19 infection.

Late Coronary Aneurysm Formation after Kawasaki Disease: a Review of Mechanistic and Clinical Aspects

Evolution of coronary artery aneurysms (CAAs) has been an ominous clinical finding in patients with Kawasaki disease (KD). CAAs generally emerge within the first few weeks in patients with KD, and appear to be strongly associated with the failure to timely initiate specific management strategies. CAA formation might occasionally arise as a late-onset phenomenon long after the index KD episode. Late CAAs in the setting of KD have particular mechanistic and clinical characteristics. Late CAAs in the setting of KD may be confused with other CAA types (atherosclerotic, etc.), and are possibly underdiagnosed in clinical practice.

In patients with Kawasaki disease (KD), evolution of coronary artery aneurysms (CAAs) generally emerges within the first few weeks after disease onset. However, CAA formation in these patients might occasionally arise as a late-onset phenomenon after a long latent period. Characteristically, late CAAs manifest as new-onset vascular pathologies or expansion of long-stable CAAs on coronary imaging modalities, and might have diverse mechanistic and clinical implications. Accordingly, the present paper aims to focus on late CAA formation and its implications in the setting of KD.

Toward precision medicine in vascular connective tissue disorders

Tremendous progress has been made in understanding the etiology, pathogenesis, and treatment of inherited vascular connective tissue disorders. While new insights regarding disease etiology and pathogenesis have informed patient counseling and care, there are numerous obstacles that need to be overcome in order to achieve the full promise of precision medicine. In this review, these issues will be discussed in the context of Marfan syndrome and Loeys-Dietz syndrome, with additional emphasis on the pioneering contributions made by Victor McKusick.

Aortic disease in Marfan syndrome is caused by overactivation of sGC-PRKG signaling by NO

Thoracic aortic aneurysm, as occurs in Marfan syndrome, is generally asymptomatic until dissection or rupture, requiring surgical intervention as the only available treatment. Here, we show that nitric oxide (NO) signaling dysregulates actin cytoskeleton dynamics in Marfan Syndrome smooth muscle cells and that NO-donors induce Marfan-like aortopathy in wild-type mice, indicating that a marked increase in NO suffices to induce aortopathy. Levels of nitrated proteins are higher in plasma from Marfan patients and mice and in aortic tissue from Marfan mice than in control samples, indicating elevated circulating and tissue NO. Soluble guanylate cyclase and cGMP-dependent protein kinase are both activated in Marfan patients and mice and in wild-type mice treated with NO-donors, as shown by increased plasma cGMP and pVASP-S239 staining in aortic tissue. Marfan aortopathy in mice is reverted by pharmacological inhibition of soluble guanylate cyclase and cGMP-dependent protein kinase and lentiviral-mediated Prkg1 silencing. These findings identify potential biomarkers for monitoring Marfan Syndrome in patients and urge evaluation of cGMP-dependent protein kinase and soluble guanylate cyclase as therapeutic targets.

Aortic aneurysm and dissection, the major problem linked to Marfan syndrome (MFS), lacks effective pharmacological treatment. Here, the authors show that the NO pathway is overactivated in MFS and that inhibition of guanylate cyclase and cGMP-dependent protein kinase reverts MFS aortopathy in mice.

Extracellular matrix dynamics in vascular remodeling

Vascular remodeling is the adaptive response to various physiological and pathophysiological alterations that are closely related to aging and vascular diseases. Understanding the mechanistic regulation of vascular remodeling may be favorable for discovering potential therapeutic targets and strategies. The extracellular matrix (ECM), including matrix proteins and their degradative metalloproteases, serves as the main component of the microenvironment and exhibits dynamic changes during vascular remodeling. This process involves mainly the altered composition of matrix proteins, metalloprotease-mediated degradation, posttranslational modification of ECM proteins, and altered topographical features of the ECM. To date, adequate studies have demonstrated that ECM dynamics also play a critical role in vascular remodeling in various diseases. Here, we review these related studies, summarize how ECM dynamics control vascular remodeling, and further indicate potential diagnostic biomarkers and therapeutic targets in the ECM for corresponding vascular diseases.