Assessing Serum Levels of ADAMTS1 and ADAMTS4 as New Biomarkers for Patients with Type A Acute Aortic Dissection

Potential biomarkers to predict return to fertility after discontinuation of female contraceptives-looking to the future

Nowadays there are multiple types of contraceptive methods, from reversible to permanent, for those choosing to delay pregnancy. Misconceptions about contraception and infertility are a key factor for discontinuation or the uptake of family planning methods. Regaining fertility (the ability to conceive) after contraceptive discontinuation is therefore pivotal. Technical studies to date have evaluated return to fertility by assessing pregnancy as an outcome, with variable results, or return to ovulation as a surrogate measure by assessing hormone levels (such as progesterone, LH, FSH) with or without transvaginal ultrasound. In general, relying on time to pregnancy as an indicator of return to fertility following contraceptive method discontinuation can be problematic due to variable factors independent of contraceptive effects on fertility, hormone clearance, and fertility recovery. Since the ability to conceive after contraceptive method discontinuation is a critical factor influencing product uptake, it is important to have robust biomarkers that easily and accurately predict the timing of fertility return following contraception and isolate that recovery from extrinsic and circumstantial factors. The main aim of this review is to summarize the current approaches, existing knowledge, and gaps in methods of evaluating return-to-fertility as well as to provide insights into the potential of new biomarkers to more accurately predict fertility restoration after contraceptive discontinuation. Biomarker candidates proposed in this document include those associated with folliculogenesis, cumulus cell expansion, follicular rupture and ovulation, and endometrial transport and receptivity which have been selected and scored on predefined criteria meant to evaluate their probable viability for advancement. The review also describes limitations, regulatory requirements, and a potential path to clinically testing these selected biomarkers. It is important to understand fertility restoration after contraceptive method discontinuation to provide users and health providers with accurate evidence-based information. Predictive biomarkers, if easy and low-cost, have the potential to enable robust evaluation of RTF, and provide potential users the information they desire when selecting a contraceptive method. This could lead to expanded uptake and continuation of modern contraception and inform the development of new contraceptive methods to widen user's family planning choices.

The Role of ADAMTS Proteoglycanases in Thoracic Aortic Disease

Thoracic aortic aneurysm and dissection (TAAD) are complex disease states with high morbidity and mortality that pose significant challenges to early diagnosis. Patients with an aneurysm are asymptomatic and typically present to the emergency department only after the development of a dissection. The extracellular matrix (ECM) plays a crucial role in regulating the aortic structure and function. The histopathologic hallmark termed medial degeneration is characterised by smooth muscle cell (SMC) loss, the degradation of elastic and collagen fibres and proteoglycan (PG) accumulation. Covalently attached to the protein core of PGs are a number of glycosaminoglycan chains, negatively charged molecules that provide flexibility, compressibility, and viscoelasticity to the aorta. PG pooling in the media can produce discontinuities in the aortic wall leading to increased local stress. The accumulation of PGs is likely due to an imbalance between their synthesis by SMCs and decreased proteolysis by A Disintegrin-like and Metalloproteinase with Thrombospondin motifs (ADAMTS) proteoglycanases in the ECM. Mouse models of TAAD indicated that these proteases exert a crucial, albeit complex and not fully elucidated, role in this disease. This has led to a mounting interest in utilising ADAMTS proteoglycanases as biomarkers of TAAD. In this review, we discuss the role of ADAMTSs in thoracic aortic disease and their potential use in facilitating the clinical diagnosis of TAAD and disease progression.

Identification of Adamts4 as a novel adult cardiac injury biomarker with therapeutic implications in patients with cardiac injuries

Pathological cardiac remodeling as an aftermath of a severe cardiac injury can lead to ventricular dysfunction and subsequent heart failure. Adamts4, a metalloproteinase, and disintegrin with thrombospondin-like motif, involved in the turnover of certain extracellular matrix molecules and pathogenesis of osteoarthritis, also plays a role in cardiac remodeling although little is presently known about its expression and function in the heart. Here, we have investigated the dynamic expression pattern of Adamts4 during cardiogenesis and also in the adult heart. To our surprise, adult cardiac injury reactivated Adamts4 expression concomitant with fibrosis induction. To better understand the mechanism, cultured H9c2 cardiomyocyte cells were subjected to ROS injury and Hypoxia. Moreover, through combinatorial treatment with SB431542 (an inhibitor of Tgf-β1), and Adamts4 siRNA mediated gene knockdown, we were able to decipher a regulatory hierarchy to the signal cascade being at the heart of Tgf-β regulation. Besides the hallmark expression of Adamts4 and Tgf-β1, expression of other fibrosis-related markers like Collagen-III, alpha-SMA and Periostin were also assessed. Finally, increased levels of Adamts4 and alpha-SMA proteins in cardiac patients also resonated well with our animal and cell culture studies. Overall, in this study, we highlight, Adamts4 as a novel biomarker of adult cardiac injury.

IL-5 overexpression attenuates aortic dissection by reducing inflammation and smooth muscle cell apoptosis

BACKGROUND

As an inflammation-related cytokine, interleukin (IL)-5 has been reported to be involved in the development of cardiovascular diseases, such as chronic heart failure and atherosclerosis. However, the role of IL-5 in acute aortic dissection (AAD) has barely been explored.

METHODS

Aortic tissue samples from normal donors and patients with AAD were collected, and the expression and localization of IL-5 in aortic tissue were analyzed. In addition, a mouse AAD model was established by administering angiotensin II (Ang II) to β-aminopropionitrile (BAPN)-treated mice. Morphological examinations and histopathologic analyses were performed to evaluate the effects of IL-5 overexpression on the occurrence of AAD.

RESULTS

IL-5 expression was significantly decreased in aorta samples from AAD patients compared to those from donors, and macrophages were the main source of IL-5. In addition, IL-5 expression was decreased in plasma and aortic tissue samples from AAD mice. IL-5 overexpression markedly attenuated the occurrence of AAD in mice and produced corresponding decreases in the inflammatory response and cell apoptosis. In cocultures of macrophages and smooth muscle cells (SMCs), IL-5 overexpression in the macrophages significantly reduced Ang II-induced SMC apoptosis.

CONCLUSION

IL-5 overexpression suppresses the development of AAD by reducing inflammation and SMC apoptosis. These results suggest that IL-5 is a potential therapeutic target in AAD.

Postnatal deficiency of ADAMTS1 ameliorates thoracic aortic aneurysm and dissection in mice

NEW FINDINGS

What is the central question of this study? Thoracic aortic aneurysm and dissection (TAAD) is characterized by extracellular matrix remodelling and an inflammatory response. Evidence suggests that ADAMTS1 is closely associated with TAAD development, but whether it contributes to the pathophysiology of TAAD remains unknown. What is the main finding and its importance? We generated inducible postnatal ADAMTS1 knockout mice and found that ADAMTS1 deficiency attenuated β-aminopropionitrile-dependent TAAD formation and rupture. Furthermore, ADAMTS1 deficiency suppressed neutrophil and macrophage infiltration by inhibiting inflammatory cytokine levels and macrophage migration during the early stage of β-aminopropionitrile-induced TAAD. ADAMTS1 could be a new therapeutic target for TAAD.

ABSTRACT

Thoracic aortic aneurysm and dissection (TAAD), as a life-threatening cardiovascular disease, is characterized by extracellular matrix remodelling and an inflammatory response. A disintegrin and metalloproteinase with thrombospondin motifs 1 (ADAMTS1) is an inflammation-related protein that is able to degrade extracellular matrix proteins in arteries. Herein, we investigated whether ADAMTS1 contributes to the pathophysiology of TAAD in mice. Using the mouse model of β-aminopropionitrile (BAPN)-induced TAAD, we found that ADAMTS1 expression was upregulated beginning in the early stage of TAAD development and localized predominantly in the aortic adventitia. ADAMTS1-floxed mice and whole-body tamoxifen-inducible ADAMTS1 knockout mice (ADAMTS1^flox/flox Ubc-Cre^ERT2+ , ADAMTS1 KO) were generated to investigate the direct causal role of ADAMTS1 in TAAD development. The incidence and rupture rates of BAPN-induced TAAD in ADAMTS1 KO mice were significantly lower than those in ADAMTS1^flox/flox mice (45.5 versus 81.8% and 18.2 versus 42.4%, respectively). Aortas from BAPN-treated ADAMTS1^flox/flox mice displayed profound destruction of the elastic lamellae, abundant neutrophil and macrophage accumulation in the adventitia, obviously increased neutrophil proportions in peripheral blood and significantly increased expression of inflammatory factors in the early stage of TAAD induction, all of which were markedly suppressed in ADAMTS1 KO mice. Furthermore, ADAMTS1-deficient macrophages exhibited abrogated migration capacity both in vivo and in vitro. In conclusion, ADAMTS1 plays a crucial role in postnatal TAAD formation and rupture by regulating inflammatory responses, suggesting that ADAMTS1 might be a new therapeutic target for TAAD.