Circulating levels of interleukin 18 reflect etiologies of heart failure: Th1/Th2 cytokine imbalance exaggerates the pathophysiology of advanced heart failure.
BACKGROUND
Proinflammatory cytokines such as tumor necrosis factor alpha play an important role in the pathophysiology of CHF. However, the mechanisms of immune activation in CHF remain unknown. Interleukin (IL)-18, a newly discovered cytokine with pleiotropic activities, is known to induce proinflammatory cytokines, chemokines, nitric oxide, and prostaglandins.


RESULTS
We studied 86 patients with New York Heart Association functional class II-IV heart failure. Mean age was 62 years, 20 were women, and mean left ventricular ejection fraction was 34.8%. Circulating levels of IL-18 and IL-10, high-sensitivity testing for C-reactive protein, and brain natriuretic peptide levels were determined. Serum IL-18 concentrations were significantly higher in patients with NYHA class IV than in patients with classes II and III (P <.001). The serum level of IL-18 and the ratio of IL-18 to IL-10 were greater in patients with ischemic cardiomyopathy than in those with dilated cardiomyopathy.


CONCLUSIONS
Th1/Th2 cytokine imbalance exists in patients with advanced CHF according to various etiologies of CHF. The findings suggest an important role for IL-18 in the pathophysiology of CHF and provide a direction for more specific immunomodulating therapy.
Yamaoka-Tojo
Minako
M
Department of Internal Medicine, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan.
Tojo
Taiki
T
Inomata
Takayuki
T
Machida
Yoji
Y
Osada
Kazuyuki
K
Izumi
Tohru
T
D016207:Cytokines / Q000097:blood; D005260:Female; D006333:Heart Failure / Q000097:blood / Q000503:physiopathology*; D006801:Humans; D016753:Interleukin-10 / Q000097:blood*; D020382:Interleukin-18 / Q000097:blood*; D008297:Male; D008875:Middle Aged; D018417:Th1 Cells; D018418:Th2 Cells
D016207:Cytokines; D020382:Interleukin-18; D016753:Interleukin-10