Relationship between TNFα and IL10 release during cardiac operations and the development of apoptosis

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Aim

To analyze the role of tumor necrosis factor (TNF)α and interleukin (IL)10 produced during cardiac operations on the development of apoptosis in vital organs and the effect of core temperature during CPB on these finding.

Methods

16 young pigs were assigned to a temperature (T°) regimen during standardized CPB: normothermia (T° 37°C; n=8) and moderate hypothermia (T° 28°C; n=8). TNFα and IL10 were determined by a pig specific ELISA. Six hours post-operative, tissue probes of the heart, liver, lung, and kidney were taken for standard- and immuno-histological examinations. Apoptotic cells were detected by an in situ apoptosis detection kit (TUNEL). Necrotic cells were counted by light microscopy.

Results

Pigs operated on in normothermia showed significantly higher TNFα production and lower IL10 production during and after CPB, and higher degree of cellular necrosis but lower degree of cellular apoptosis than pigs operated on in moderate hypothermia. In all animals, postoperative IL10 levels were negatively correlated with the production of myocardial apoptosis (P=0.005) and TNFα levels correlated significantly with necrosis in the heart and liver (P<0.05).

Conclusion

Cardiac operations are related to cell death via both the necrotic and the apoptotic pathways. In this setting, IL10 could be an inductor of apoptosis. By increasing the production of IL10 and the ratio apoptosis/necrosis, moderate hypothermia during CPB might therefore provide organ protection.