FABP4 and metabolic syndrome: Among FABPs, FABP4 and FABP5 have been shown to be secreted into bodily fluids such as plasma [3,6,7], and the levels of these FABPs have also been shown to be significantly correlated with various pathological aspects of metabolic syndrome and cardiovascular disease [8], suggesting that FABP4 and FABP5 may be critical biomarkers for these diseases.