Pulmonary production of osteopontin in humans: effects of left ventricular systolic dysfunction and cardiopulmonary bypass.
BACKGROUND
We evaluated pulmonary production of osteopontin (OPN) in left ventricular systolic dysfunction (LVSD) and after cardiopulmonary bypass surgery (CPB). OPN is a phosphoglycoprotein involved in inflammation and remodeling. In subjects with LVSD, plasma OPN correlates with prognosis but its origin is unknown. We hypothesized that the lungs produce OPN and that this could be affected by LVSD and CPB.


RESULTS
Subjects with (n = 57; left ventricular ejection fraction [LVEF] 32 ± 8%) and without (n = 63; LVEF 59 ± 7%) LVSD were studied during CPB. Arterial and venous OPN plasma levels were determined. Arterial and venous OPN levels were higher in LVSD (P = .0290). For both groups, levels dropped 1 hour after surgery and nearly doubled 24 hours after (P < .0001 vs basal). Notably, there was a significant positive arteriovenous gradient with arterial levels higher than venous levels. Arteriovenous differences were statistically significant at baseline (P = .0120) and 1 hour (P < .0001) but not at 24 hours (P = .0649). Arterial levels in heart failure correlated inversely with renal function (P = .016) and positively with mean pulmonary pressure (P = .028), heart rate (P = .036), and C-reactive protein (P = .047).


CONCLUSIONS
There is production of circulating OPN by the lungs, unaffected by LVSD or CPB. This likely represents an overflow from local lung production and does not contribute to increased levels in LVSD or after CPB.
Department of Anesthesiology, Montreal Heart Institute and Université de Montréal, Montreal, Quebec, Canada; Research Center, Montreal Heart Institute and Université de Montréal, Montreal, Quebec, Canada.
Christian
C
Ayoub
Montreal Heart Institute Coordinating Center, Montreal, Quebec, Canada.
Anna
A
Nozza
Department of Anesthesiology, Montreal Heart Institute and Université de Montréal, Montreal, Quebec, Canada; Research Center, Montreal Heart Institute and Université de Montréal, Montreal, Quebec, Canada.
André
A
Denault
Department of Anesthesiology, Montreal Heart Institute and Université de Montréal, Montreal, Quebec, Canada; Research Center, Montreal Heart Institute and Université de Montréal, Montreal, Quebec, Canada.
Alain
A
Deschamps
Research Center, Montreal Heart Institute and Université de Montréal, Montreal, Quebec, Canada; Department of Medicine, Montreal Heart Institute and Université de Montréal, Montreal, Quebec, Canada. Electronic address: jocelyn.dupuis@bellnet.ca.
Jocelyn
J
Dupuis
D000368:Aged; D015415:Biomarkers / Q000097:blood; D002315:Cardiopulmonary Bypass / Q000639:trends; D005260:Female; D006801:Humans; D008168:Lung / Q000098:blood supply* / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D053495:Osteopontin / Q000096:biosynthesis / Q000097:blood*; D018487:Ventricular Dysfunction, Left / Q000097:blood* / Q000175:diagnosis / Q000601:surgery*
D015415:Biomarkers; D053495:Osteopontin
Remodeling; pulmonary heart disease; pulmonary hypertension