Background: Toll-like receptors (TLRs) are key mediators of the innate immune system and activated by extracellular stresses such as free radicals, cytokines, or infection. Curcumin, a polyphenolic compound derived from dietary spice turmeric, has been reported to scavenge free radicals and to inhibit nitric oxide synthase activity, lipoxygenase, and cyclooxygenase activities involved in inflammatory pathways. We assessed the hypothesis that curcumin protected cardiac cells via TLR2 inhibition. Methods: Cardiac ischemia-reperfusion injury (IR) was induced by ligation of left anterior descending artery for 30 minutes followed by release in Sprague-Dawley rats. TLR2 mRNA and protein were examined by RT-PCR and Western blot, respectively. To study the effect of curcumin on cardiomyocytes (CMs), vascular smooth muscle cell (VSMC), and human umbilical vein endothelial cells (HUVECs) were utilized. CM, VSMC and HUVEC were isolated from neonatal rat ventricle, adult rat thoracic aorta, and human umbilical cord, respectively. These cells were stimulated with tumor necrosis factor (TNF)-慣 (10 ng/mL) and TLR2 agonist peptidoglycan (PGN, 10 關g/mL) in the presence or absence of curcumin (10 關M). Results: In IR rat, TLR2 mRNA was increased both in infarct and peri-infarct myocardium in 2 weeks, while TLR4 mRNA was remained unchanged. To examine whether TLR2 is involved in cardiac injury system, CMs were utilized. TLR2 expression was increased in CMs by TNF-慣 in 24 hours, while TLR4 remained unchanged. TLR2 expression as well as monocyte chemoattractant protein (MCP)-1, interleukin (IL)-6, and plasminogen activator protein (PAI)-1 were induced by both TNF-慣 and PGN in CMs, whereas pretreatment of curcumin with CMs blunted their induction significantly. In addition to CM, VSMCs and HUVECs increased TLR2, MCP-1, and IL-6 expression in response to TNF-慣 and PGN, and curcumin reduced the expressions of them. Conclusions: We suggest that TLR-2, not TLR-4, might be an important mediator in response to myocardial ischemic stimulation, and TNF-慣 might act as a ligand to TLR2 in CM, VSMC, and HUVEC. The inhibition of TLR2 by using curcumin could be proposed as a therapeutic tool.