AMPK Activation By Ozone Therapy Inhibits Tissue Factor-Triggered Intestinal Ischemia And Ameliorates Chemotherapeutic Enteritis

Chemotherapeutic enteritis is a major dose-limiting adverse reaction to chemotherapy,and few effective drugs are currently available in clinic.Recently the mechanism of intestinal ischemic injury has emerged in the research spotlight due to its notable influence on chemotherapeutic enteritis.Therefore,the pathological mechanism of ischemic injury remains unclear.Chemotherapy induces the release of large amounts of danger-associated molecular patterns(DAMPs,such as HSP70 and HMGB-1).Researches combined with our latest research showed that DAMPs were the endogenous ligands of TLR-4 pathway.In addition,the expression of tissue factor(TF)in TLR-4 knockout mice was decreased,suggesting that TF is a downstream molecule of the TLR-4 receptor pathway,and TF is also a core factor of persistent coagulation state and deep vein thrombosis induced by chemotherapy.Therefore,a scientific hypothesis of the pathogenesis of chemotherapeutic enteritis was proposed.Chemotherapy could induce the high expression of TF in the intestinal microenvironment,and lead to intestinal thrombosis and ischemic injury through exogenous coagulation pathway,eventually leading to chemotherapeutic enteritis.Ozone therapy is an alternative and effective approach in certain clinical circumstances,especially in analgesic therapy.Our previous study demonstrated that medical ozone could attenuate neuropathic pain by activating AMPK.We also demonstrated that AMPK activation could inhibit neuroinflammation via up-regulate SOCS3 expression to suppress the TLR-4/p38 signaling pathway.The aforementioned studies encouraged us to explore the potential protective effects of ozone therapy on chemotherapeutic enteritis and to investigate the role of AMPK/SOCS3-mediated negative inflammatory feedback in the strategy.Methods:This study employed irinotecan(CPT-11)to establish chemotherapeutic enteritis animal model.Western blotting,gelatin zymography,immunohistochemistry(IHC),intestinal blood flow measurement were used to detect the pathogenesis of ischemia-hypoxia injury in chemotherapeutic enteritis.On this basis,we found an effective strategy,ozone therapy,to chemotherapeutic enteritis by alleviating ischemic-hypoxic injury.Results:The results showed that CPT-11 increased levels of tissue factor(TF)both in the blood and in intestines in mice.Interestingly,the elevation of TF in the blood displayed "double-peak",which was consistent with the intestinal mucosal"double-strike" injury trend.CPT-11 could decrease the intestinal blood flow,which was detected by Laser Doppler flowmetry(LDF).Moreover,we found that ozone therapy,a novel and practical therapeutic strategy,could relieve chemotherapeutic enteritis in mice.We also found that ozone autotransfusion therapy could effectively attenuate chemotherapeutic enteritis and improve the blood hypercoagulability in cancer patients.Ozone therapy could inhibit TF expression induced by CPT-11 and effectively ameliorate the intestinal mucosal injury in mice.Further research showed that ozone could activate AMPK/SOCS3 to inhibit TLR-4/p38/TF signaling pathway.Conclusions:For the first time,we proposed that TF-induced thrombotic intestinal ischemic injury is a core trigger pathological mechanism of chemotherapeutic enteritis.We also proposed a new treatment strategy,ozone therapy,to suppress TF expression by activating AMPK.The innovation of this study:Our study demonstrated for the first time that intestinal ischemia and hypoxia injury induced by TF-triggered microthrombus was a core trigger of chemotherapeutic enteritis,and provided a potential treatment strategy,ozone therapy,for inhibiting the high expression of TF to ameliorate chemotherapeutic enteritis.