The endogenous vascular elastase that governs development and progression of monocrotaline-induced pulmonary hypertension in rats is a novel enzyme related to the serine proteinase adipsin.

Abstract

We showed previously a cause and effect relationship between increased activity of an endogenous vascular elastase (EVE) and experimentally induced pulmonary hypertension in rats. We now report the isolation and characterization of EVE. Degenerate oligonucleotides synthesized to homologous sequences in serine elastases were used in a PCR with rat pulmonary artery (PA) cDNA. The PCR product hybridized to a 1.2-kb mRNA and the intensity of hybridization was threefold increased in RNA from rat hypertensive PA at a timepoint when EVE activity was increased. The PCR product was used to screen a cDNA library and sequences obtained encoded rat adipsin. We then used immunoaffinity to purify EVE. An antibody to the elastin-binding protein was used to remove this competitor of elastase from the PA extract and the elastolytic activity increased 100-fold. The enzyme was purified using an antibody that recognizes NH2-terminal sequences of serine proteinases and the eluate was further purified using an antibody raised against recombinant adipsin. A single band at 20 kD immunoreactive with the adipsin antibody was resolved as an active enzyme on an elastin substrate gel. Immunogold labeling with an antibody to an adipsin peptide sequence localized EVE to PA smooth muscle cells. This is the first isolation of EVE; it appears to be a novel enzyme related to the serine proteinase adipsin originally found in adipose tissue. (J.

Gene Transfer of the Serine Elastase Inhibitor Elafin Protects Against Vein Graft Degeneration

“…Sources of serine elastases include SMCs, which produce an endogenous elastase in response to endothelial injury or activation. 2,14,15 However, infiltrating leukocytes may also contribute to elevated serine elastase activity in vein grafts. 16 A critical role for inflammatory cells in neointimal formation has been suggested by the observation that neointimal formation is reduced in vein grafts from rats that lack T cells or are administered cyclosporin A.…”

Myocardial oxidative stress changes during compensated right heart failure in rats

“…(Pan et al 1993). Other relevant damage includes a thickeaing of the alveolar septa that is associated with the loss of pulmonary capflanes (Boor et al 1994) and abnormal muscuiarization of nonnally non muscular peripheral arteries as a result of differentiation of precunor cells to smooth muscle cells (Zhu et al 1994). …”

Targeted overexpression of elafin protects mice against cardiac dysfunction and mortality following viral myocarditis

“…For example, elevated serine elastase activity has been reported in patients with myocardial infarction and unstable angina (4), peripheral and coronary artery disease (2), and abdominal aortic aneurysm (3). In experimental studies, high elastin turnover (5) is associated with increased expression of an endogenous vascular elastase in the development and progression of pulmonary hypertension (6)(7)(8)12). Moreover, inhibition of elastase activity reduces or prevents the development of pulmonary hypertension and associated changes in the pulmonary arteries (7,8).…”