Dipeptidyl Peptidase IV in Angiotensin-Converting Enzyme Inhibitor–Associated Angioedema

• Published in: Hypertension (Dallas, Tex. 1979) Vol. 51; no. 1; pp. 141 - 147
• Main Authors: Byrd, James Brian, Touzin, Karine, Sile, Saba, Gainer, James V, Yu, Chang, Nadeau, John, Adam, Albert, Brown, Nancy J
• Format: Journal Article
• Language: English
• Published: United States American Heart Association, Inc 01-01-2008
• Subjects: Adult; Aged; Angioedema - chemically induced; Angioedema - enzymology; Angiotensin-Converting Enzyme Inhibitors - adverse effects; Angiotensin-Converting Enzyme Inhibitors - therapeutic use; Antigens - immunology; Bradykinin - metabolism; Case-Control Studies; Dipeptidyl Peptidase 4 - genetics; Dipeptidyl Peptidase 4 - immunology; Dipeptidyl Peptidase 4 - metabolism; Female; Genetic Predisposition to Disease; Humans; Hypertension - drug therapy; Male; Middle Aged; Peptidyl-Dipeptidase A - metabolism; Substance P - metabolism
• ISSN: 0194-911X; 1524-4563
• DOI: 10.1161/HYPERTENSIONAHA.107.096552

Angioedema is a potentially life-threatening adverse effect of angiotensin-converting enzyme inhibitors. Bradykinin and substance P, substrates of angiotensin-converting enzyme, increase vascular permeability and cause tissue edema in animals. Studies indicate that amino-terminal degradation of these peptides, by aminopeptidase P and dipeptidyl peptidase IV, may be impaired in individuals with angiotensin-converting enzyme inhibitor–associated angioedema. This case-control study tested the hypothesis that dipeptidyl peptidase IV activity and antigen are decreased in sera of patients with a history of angiotensin-converting enzyme inhibitor–associated angioedema. Fifty subjects with a history of angiotensin-converting enzyme inhibitor–associated angioedema and 176 angiotensin-converting enzyme inhibitor–exposed control subjects were ascertained. Sera were assayed for angiotensin-converting enzyme activity, aminopeptidase P activity, aminopeptidase N activity, dipeptidyl peptidase IV activity, and antigen and the ex vivo degradation half-lives of bradykinin, des-Arg-bradykinin, and substance P in a subset. The prevalence of smoking was increased and of diabetes decreased in case versus control subjects. Overall, dipeptidyl peptidase IV activity (26.6±7.8 versus 29.6±7.3 nmol/mL per minute; P=0.026) and antigen (465.8±260.8 versus 563.1±208.6 ng/mL; P=0.017) were decreased in sera from individuals with angiotensin-converting enzyme inhibitor–associated angioedema compared with angiotensin-converting enzyme inhibitor–exposed control subjects without angioedema. Dipeptidyl peptidase IV activity (21.5±4.9 versus 29.8±6.7 nmol/mL per minute; P=0.001) and antigen (354.4±124.7 versus 559.8±163.2 ng/mL; P=0.003) were decreased in sera from cases collected during angiotensin-converting enzyme inhibition but not in the absence of angiotensin-converting enzyme inhibition. The degradation half-life of substance P correlated inversely with dipeptidyl peptidase IV antigen during angiotensin-converting enzyme inhibition. Environmental or genetic factors that reduce dipeptidyl peptidase IV activity may predispose individuals to angioedema.