Up-regulated fatty acid-binding protein 4 promoted cardiac injury during open colorectal surgery in elderly patients

Fatty acid binding protein 4 (FABP4) has been shown to increase cardiovascular disease. The FABP4 levels in serum and adipose tissue and the possible regulatory mechanisms during colorectal cancer surgery in elderly patients remain unknown.

Four hundred elderly patients with colorectal cancer were recruited, 200 underwent laparoscopic surgery (LS) and 200 underwent open surgery (OS). Blood samples and mesenteric adipose tissue were collected at T1 (beginning of surgery) and T2 (end of surgery). Immunohistochemistry and biochemical analysis were used to evaluate the FABP4, cardiac troponin T (cTnT), creatine kinase-MB (CK-MB) and myoglobin (MYO) levels. Correlations between FABP4 and cTnT, CK-MB, MYO were further analyzed.

The expressions of FABP4 in mesenteric adipose tissue were significantly increased at T2 than T1 in OS group. The serum levels of FABP4, cTnT, CK-MB and MYO were significantly increased at T2 than T1 in OS group, and the OS group induced higher FABP4, cTnT, CK-MB and MYO levels than LS group at T2. Pearson's correlation analysis revealed that serum levels of FABP4 were strongly correlated with cTnT, CK-MB, and MYO.

OS induced significantly increased FABP4 expressions in adipose tissue and caused cardiac injury in elderly patients with colorectal cancer. FABP4 is closely associated with cardiac injury, raising the possibility that adipose tissue may be causally involved in the pathogenesis of heart dysfunction during open surgery.