The pathogenesis of heatstroke is a multi-factorial process involved with an interplay among subsequent inflammation, endothelial injury and coagulation disturbances, which makes pharmacological therapy of heatstroke a challenging problem. Xuebijing injection (XBJ), a traditional Chinese medicine used to sepsis, has been reported to suppress inflammatory responses and restore coagulation disturbances. However, little is known about the role of XBJ in heatstroke.

XBJ prevents organ injuries and improves survival in heatstroke mice by attenuating inflammatory responses and endothelial injury. XBJ may be a potentially useful in the prevention and treatment of heatstroke.

Mice were treated with indicated dose of XBJ before and/or after the induction of heatstroke. Serum inflammatory cytokines, tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), and endothelial markers, von Willebrand Factor (vWF) and E-selectin, were measured by ELISA. Liver, kidney and heart profiles including alanine aminotransferase, aspartic aminotransferase, creatinine, blood urea nitrogen, and lactate dehydrogenase, were evaluated by UniCel DxC 800 Synchron Clinical Systems, and troponin was measured by ELISA. Coagulation profiles, including thrombin time, prothrombin time, activated partial thromboplastin time, international normalized ratio, and fibrinogen were examined by STA Compact® Hemostasis System. Jejunum injury was evaluated with H&E staining. Changes in mitochondrial structure in cardiac tissue were assesed by electron microscopy.

Pretreatment with XBJ decreased serum pro-inflammatory cytokines including TNF-α and IL-6, as well as endothelial injury markers, vWF and E-selectin, in a dose-dependent manner in heatstroke mice. Similar protective effects were observed when XBJ was administered after, or both before and after heat insult. These protective effects lasted for over 12 h in mice receiving XBJ before and after heat insult. XBJ also improved survival rates in heatstroke mice, ameliorated liver, heart, and kidney injuries, including mitochondrial damage to the heart, and reduced coagulation disturbances. Conclusions: XBJ prevents organ injuries and improves survival in heatstroke mice by attenuating inflammatory responses and endothelial injury. XBJ may be a potentially useful in the prevention and treatment of heatstroke.