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Objective To investigate the effects of mesenchymal stem cells(MSCs)on the pathological structure and cytokine expression of lung tissue in septic model of diabetic rats. Methods Diabetic rats were ran-domly divided into control,sham-operation,sepsis and MSC-treated groups. The diabetic model was induced by high-sucrose and high-fat diet combined with streptozotocin and cecal ligation and puncture. The pathological changes of lung tissue were observed at 6,12,18 and 24 hours after operation respectively,and the expression of SP-D,TNF-α,IFN-γ and IL-10 in lungs were measured.Results The levels of SP-D,TNF-α and IFN-γ in lung tissue increased gradually with the elongation of time after CLP. The expression of IL-10 in lung tissue increased and then decreased. The trend of MSC intervention increased the content of SP-D,TNF-α and IL-10 in the lung tissue of non-diabetic septic rat model and reduced the content of IFN-γ.MSC intervention reduced the SP-D and TNF-α content.The intervention of MSC had no effect on the content of IFN-γ in the lung tissue of diabetic septic rats.However,it increased and then decreased the content of IL-10.Conclusions The model of sepsis in diabetic rats can be established by feeding combined high-sugar and high-fat diet and streptozotocin combined with cecal ligation and puncture. Mesenchymal stem cells affect sepsis inflammation and organ damage. But its specific role depends on the immune status and the timing of mesenchymal stem cell selection.
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Objective To evaluate the effects of meglumine cyclic adenylate (MCA) pretreatment on acute lung injury (ALI) induced by lipopolysaccharide (LPS) in rats.Methods Fifty-four adult male Sprague Dawley rats,aged 2-3 months,weighing 200-250 g,were randomly divided into 3 groups (n =18 each) using a random number table:control group (group C),ALI group and MCA pretreatment group (group MCA).ALI was induced with LPS 10 mg/kg injected via the femoral vein in ALI and MCA groups.In group MCA,MCA 2 mg/kg was injected via the femoral vein at 20 min before LPS injection,while the equal volume of normal saline was given in C and LPS groups.Immediately before LPS injection and at 2 and 4 h after LPS injection,the blood samples were taken from the abdominal aorta for determination of PaO2,PaCO2 and plasma concentrations of tumor necrosis factor-alpha (TNF-α) and interleukin-10 (IL-10).Six rats were sacrificed at 4 h after LPS injection and pulmonary specimens were obtained for microscopic examination of the pathological changes and for determination of cyclic adenosine monophosphate (cAMP) activity (by ELISA) and NF-κB p65 expression in nucleus (by Western blot).Results Compared with group C,PaO2 and cAMP activity in lung tissues were significantly decreased,and PaCO2,plasma concentrations of IL-10 and TNF-α and NF-κB p65 expression in nucleus in lung tissues were increased in group LPS.Compared with group LPS,PaO2,cAMP activity in lung tissues and plasma concentrations of IL-10 were significantly increased,and PaCO2,plasma concentration of TNF-α and NF-κB p65 expression in nucleus in lung tissues were decreased and the pathologic changes of lungs were attenuated in group MCA.Conclusion MCA pretreatment can attenuate ALI induced by LPS,and the mechanism is related to increased level of cAMP,activated cAMP signaling pathway,inhibited NF-κB activity and reduced inflammatory responses in lung tissues of rats.
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Objective To evaluate the effect of nicotine pretreatment on cardiac function following myocardial ischemia-reperfusion (I/R) in rats.Methods Sixty male Sprague-Dawley rats,weighing 200-250 g,were randomly divided into 3 groups (n =20 each):sham operation group (group S),group I/R and nicotine pretreatment group (group N).The rats were anesthetized with intraperitoneal 20％ urethane 1 g/kg,tracheostomized and mechanically ventilated.Myocardial ischemia was induced by occlusion of the left anterior descending branch of coronary artery for 30 min followed by 120 min of reperfusion.The left anterior descending branch of coronary artery was only exposed,but not occluded in group S.Nicotine 400 μg/kg was injected intravenously via the right jugular vein at 30 min before myocardial ischemia in group N.The equal volume of normal saline was injected instead in groups S and I/R.Before ischemia,at 30 min of ischemia and at 30 and 120 min of reperfusion,10 rats from each group were chosen for record of left ventricular systolic pressure (LVSP),left ventricular diastolic pressure (LVDP),± dp/dtmax,HR and mean arterial pressure (MAP).Blood samples were collected from the right carotid artery of the left 10 rats in each group at 60 min of reperfusion to measure plasma CK-MB activity and cTnI and TNF-α concentrations.Results Compared with group S,MAP and LVSP at T2,3 and HR,LVDP and ± dp/dtmax at T1-3 were significantly decreased,and the plasma CK-MB activity and cTnI and TNF-α concentrations were increased in group I/R,and LVDP at T1,2 and HR and ± dp/dtmax at T1-3 were significantly decreased,and the plasma CK-MB activity and cTnI and TNF-α concentrations were increased in group N (P ＜ 0.05).Compared with group I/R,MAP,HR,LVSP,LVDP and ± dp/dtmax were significantly increased at T3,and the plasma CK-MB activity and cTnI and TNF-α concentrations were decreased in group N (P ＜ 0.05).Conclusion Nicotine pretreatment can reduce myocardial I/R injury through activating cholinergic anti-inflammatory pathway,thus improving cardiac function in rats.