Dept. of Surgery and Dept. of Pathobiology, Univ. of Pennsylvania, 500 South Ridgeway Ave., Glenolden, PA 19036.
Published: November 2013
AI Article Synopsis
Article Abstract
Caldesmon (CaD), a component of smooth muscle thin filaments, binds actin, tropomyosin, calmodulin, and myosin and inhibits actin-activated ATP hydrolysis by smooth muscle myosin. Internal deletions of the chicken CaD functional domain that spans from amino acids (aa) 718 to 731, which corresponds to aa 512-530 including the adjacent aa sequence in mouse CaD, lead to diminished CaD-induced inhibition of actin-activated ATP hydrolysis by myosin. Transgenic mice with mutations of five aa residues (Lys(523) to Gln, Val(524) to Leu, Ser(526) to Thr, Pro(527) to Cys, and Lys(529) to Ser), which encompass the ATPase inhibitory determinants located in exon 12, were generated by homologous recombination. Homozygous (-/-) animals did not develop, but heterozygous (+/-) mice carrying the expected mutations in the CaD ATPase inhibitory domain (CaD mutant) matured and reproduced normally. The peak force produced in response to KCl and electrical field stimulation by the detrusor smooth muscle from the CaD mutant was high compared with that of the wild type. CaD mutant mice revealed nonvoiding contractions during bladder filling on awake cystometry, suggesting that the CaD ATPase inhibitory domain suppresses force generation during the filling phase and this suppression is partially released by mutations in 50% of CaD in heterozygous. Our data show for the first time a functional phenotype, at the intact smooth muscle tissue and in vivo organ levels, following mutation of a functional domain at the COOH-terminal region of CaD.
Department of Emergency Medicine, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong, China.
Aortic dissection (AD) represents a critical condition characterised by a tear in the inner lining of the aorta, leading to the leakage of blood into the layers of the aortic wall, posing a significant risk to life. However, the pathogenesis is unclear. In this study, scRNA-seq was applied to cells derived from aortas of both AD and non-AD donors (control) to unveil the cellular landscape.
Introduction: Pulmonary hypertension (PH) is a progressive and life-threatening condition. Recent research has demonstrated that exosomes derived from mesenchymal stem cells (MSC) exhibit significant therapeutic potential in the treatment of PH. The composition of these exosomes is often substantially influenced by the characteristics of their parental cells.
Introduction: Arterial stiffening is a hallmark of vascular ageing, and unravelling its underlying mechanisms has become a central theme in the field of cardiovascular disease. While various techniques and experimental setups are accessible for investigating biomechanics of blood vessels both in vivo and ex vivo, comparing findings across diverse methodologies is challenging.
Methods: Arterial stiffness in the aorta of adult (5 months) and aged (24 months) wild-type C57Bl/6J mice was measured in vivo, after which ex vivo biomechanical evaluation was performed using the Rodent Oscillatory Tension Setup to study Arterial Compliance (ROTSAC; University of Antwerp, Belgium) and the DynamX setup (Maastricht University, The Netherlands).
Background: TPM3 (tropomyosin 3) is an actin-binding protein in vascular smooth muscle cells, where posttranslational modifications critically regulate its actin affinity, influencing cardiovascular function. Emerging evidence suggests that Khib (2-hydroxyisobutyrylation) plays a significant role in the cardiovascular system. Histone deacetylase 3 (HDAC3) serves as an "eraser" of Khib marks.
Background: Aortic valve stenosis (AVS) is a progressive disease characterized by fibrosis, inflammation, calcification, and stiffening of the aortic valve leaflets, leading to disrupted blood flow. If untreated, AVS can progress to heart failure and death within 2 to 5 years. Uncovering the molecular mechanisms behind AVS is key for developing effective noninvasive therapies.
