FABP4 and metabolic syndrome: FABP4 is known to be secreted mainly from adipocytes [5, 6], and circulating FABP4 concentration has been reported to be associated with a risk of various diseases, such as atherosclerosis [7, 8], insulin resistance [9], type2 diabetes [10], hypertension [9, 11], dyslipidemia [9, 12], cardiovascular diseases [13,14], and cancer [15].