ObjectiveSepsis is a systemic inflammatory response syndrome. Emodin is a major ingredient of Rheum Palmatum, a Chinese herb that is widely used in China for treatment of endotoxemia-related diseases. This study intended to examine the effect of Emodin on LPS-induced rat mesenteric microcirculatory disturbance and the underlying mechanisms. MethodsThe male Wistar rats received LPS (5 mg/kg/hr) for 90 min, with or without administration of Emodin (10 mg/kg/hr) by enema 30 min before (pre-treatment) or after (post-treatment) LPS infusion, and the dynamics of mesenteric microcirculation were determined by inverted intravital microscopy. Expression of adhesion molecules and TLR4, NF-B p65, ICAM-1, MPO, and AP-1 in mesentery tissue was evaluated by flow cytometry and Western-blot, respectively. ResultsPre or post-treatment with Emodin significantly ameliorated LPS-induced leukocyte emigration, reactive oxygen species production and albumin leakage, and the expression of TLR4, NF-B p65, ICAM-1, MPO and AP-1 in mesentery. ConclusionsThese results demonstrate the beneficial role of Emodin in attenuating the LPS-induced microcirculatory disturbance, and support the use of Emodin for patients with endotoxemia.