AIMTo investigate the role and mechanism of mitochondrial calcium uniporter (MCU) in myocardial hypoxia/reoxygenation injury.

METHODSIsolated rat hearts were perfused with Langendorff apparatus. The hypoxia/reoxygenation injury was achieved by ligation of left anterior coronary artery for 30 min followed by release of ligation for 120 min. The left ventricular developed pressure (LVDP), the maximum rise/fall rate of left ventricular pressure (+/- dP/dt(max)), and the left ventricular end-diastolic pressure (LVEDP) were recorded. Activities of lactate dehydrogenase (LDH) in coronary effluent and reactive oxygen species (ROS) of myocardial mitochondria were spectrophotometrically assayed. Infarct size was determined by TTC staining method.

RESULTSCompared with the hypoxia/reoxygenation (H/R) group, ruthenium red (RR, 5 micromol/L), given at the on set of reoxygenation, significantly improved the contractile function of left ventricle, decreased the myocardial infarct size, alleviated the production of ROS in myocardial mitochondria and LDH release in coronary effluent. Spermine (20 micromol/L), given at the onset of reoxygenation, enhanced the production of ROS in the mitochondria and LDH release in coronary effluent at 5, 20 and 30 min of reoxygenation, however, there were no significant differences of ventricular contractile parameters and infarct size between groups subjected to hypoxia/reoxygenation with or without spermine treatment. Co-treatment of ROS scavenger N-2-mercaptopropionyl glycine (1 mmol/L) with spermine abolished the effect of spermine.

CONCLUSIONInhibition of mitochondrial calcium uniporter may refrain heart from hypoxia/reoxygenation injury via decreasing the production of ROS in heart mitochondria.

Animals ; Calcium Channels ; metabolism ; Cell Hypoxia ; In Vitro Techniques ; Male ; Mitochondria, Heart ; metabolism ; Myocardial Ischemia ; metabolism ; Rats ; Rats, Sprague-Dawley ; Reactive Oxygen Species ; metabolism

Objective To search for the changes of T cells subpopulations and immunoglobulin and their relation-ship in children patients with simple nephrotic syndrome. Design Case-control research. Patients aud Participants 39 patients with simple nephrotic syndrome were divided into two groups:the incipient group and relapse group (6 cases were determined at the incipient and relapse time) .Thereare 28 patients in incipient group, 19 males and 9 females, at the age of 2 to 10 years old. There are20 patients in relapse group, 12 males and 8 females, at the age of 3 to 13 years old. There are 35health children in control group, 21 males and 14 females, 2～13 years old. Interventions T cells subpopulations were determined by indirect immunofluorescence of OKT linesmonoclonal antibodies. The serum IgG was determined by routine simple agar immunodiffusion tests. Results and Conclusions The CD_3~+ and CD_4~+ cells are of no change in the children patients withsimple nephrotic syndrome, and the CD_8~+ and CD_(10)~+ cells are obviously increased, the Values of CD_4~+/CD_8~+ are obviously lower than those in the control qroup, there are no difference between the incipientand relapse groups. The levels of serum IgG were decreased in the 85.3% children patients, IgM were inc-reased in 29.4% of that. The values of CD_4~+/CD_8~+ have positive correlation and negative correlationwith the levels of serum IgG and IgM respectively.

AIMTo observe the differences of hemodynamics and nitric oxide synthase(NOS) activity of ventricular cardiac muscle in two septic shock models and explore the possible mechanism.

METHODSTwo rat models of septic shock[lipopolysaccharide(LPS)-induced and cecal ligation and puncture (CLP)-induced septic shock] were used. The hemodynamic parameters and nitric oxide synthase activity of ventricular cardiac muscle were measured.

RESULTSThe hemodynamic parameters in CLP-induced model were increased in the early stage and decreased in the late stage while in LPS-induced model the parameters showed the same change of the CLP late stage. Both LPS model and CLP model (late stage) showed significant increase in NOS activity, but there was no difference between the two models. After treatment of the NOS inhibitor N-nitro-L-arginine methyl ester (L-NAME), the parameters of CLP-late stage and LPS model increased significantly. The NOS activity reached the highest level in the CLP-middle stage. The production of nitrite/nitrate decreased significantly in LPS model and CLP model(late stage) after treatment of L-NAME, but the nitrite/nitrate produced by constitutive NOS in LPS model was higher than CLP model(late stage).

CONCLUSIONThe increase of the NOS activity may be the main reason to lead to the depression of the hemodynamic parameters. Inducible NOS may play the leading role in the LPS model while cNOS and iNOS have the same effect in the CLP model.

Animals ; Hemodynamics ; Lipopolysaccharides ; Male ; Myocytes, Cardiac ; metabolism ; Nitric Oxide Synthase ; metabolism ; Rats ; Rats, Sprague-Dawley ; Shock, Septic ; classification ; metabolism

OBJECTIVETo investigate whether the cardioprotection of mitochondrial Slo channel (mitoSlo(1) channel) is associated with mitochondrial permeability transition in isolated rat hearts subjected to ischemia and reperfusion.

METHODSIsolated perfused rat hearts were subjected to 30 min regional ischemia (occlusion of left anterior descending artery) and 120 min reperfusion. The infarct size, lactate dehydrogenase (LDH) release during reperfusion and ventricular hemodynamic parameters were measured.

RESULTSPretreatment with mitoSlo(1) channel opener, NS1619 10 micromol/L for 10 min reduced the infarct size and LDH release, and improved the recovery of left ventricular developed pressure, left ventricular end-diastolic pressure, maximal rise/fall rate of left ventricular pressure and coronary flow during reperfusion. Administration of atractyloside (20 micromol/L), an opener of mitochondrial permeability transition pore, for 20 min (last 5 min of ischemia and first 15 min of reperfusion) attenuated the reduction of infarct size and LDH release and improvement of left ventricular performance induced by NS1619. In the isolated mitochondria, a significant inhibition of Ca(2+)-induced swelling was observed when mitochondria were incubated with NS1619.

CONCLUSIONMitoSlo(1) channel activation by NS1619 protects the myocardium against ischemia and reperfusion injury by inhibiting mitochondrial permeability transition pore opening.

Animals ; Atractyloside ; pharmacology ; Cardiotonic Agents ; pharmacology ; Heart ; In Vitro Techniques ; Ischemic Preconditioning, Myocardial ; Mitochondria, Heart ; drug effects ; Mitochondrial Membrane Transport Proteins ; Myocardial Reperfusion Injury ; metabolism ; prevention & control ; Permeability ; drug effects ; Potassium Channels ; metabolism ; Potassium Channels, Calcium-Activated ; metabolism ; Rats

Objective To detect anti-M_2 autoantibody using recombinant BCOADC-E_2.Methods We purified recombinant BCOADC-E_2 by Ni~(2+)affinity chromatography column and then detect anti-M_2 autoan- tibody in the sera of patients with primary biliary cirrhosis(PBC)by Western blot test(WBT)and enzyme linked immunosorbent assays(ELISA).Results Among 60 sera from PBC patients,33 were positive,all of controls were negative.Conclusion The recombinant BCOADC-E_2 can be used to detect anti-M_2 autoanti- body specifically and sensitively.It is helpful for the diagnosis of PBC.

OBJECTIVETo investigate the effect of kappa-Opioid receptors in the cardioprotection elicited by ischemic postconditioning and the underlying mechanism.

METHODSThe isolated perfused hearts of male Sprague-Dawley rats were subjected to 30 min of global ischemia followed by 120 min of reperfusion. formazan content of myocardium was measured spectrophotometrically, and the level of lactate dehydrogenase (LDH) in the coronary effluent was also measured. In isolated ventricular myocytes hypoxia postconditioning was achieved by 3 cycles of 5 min reoxygenation/5 min hypoxia starting at the beginning of reoxygenation, and cell viability was measured.

RESULTIn the Langendorff perfused rat heart model, ischemic postconditioning (6 cycles of 10 s reperfusion/10 s global ischemia starting at the beginning of reperfusion) increased formazan content, reduced LDH release, improved the recovery of the left ventricular developed pressure, maximal rise/fall rate of left ventricular pressure, left ventricular end-diastolic pressure and rate pressure product (left ventricular developed pressure multiplied by heart rate), attenuated the decrease of coronary flow during reperfusion and increased the isolated cell viability. Pretreatment with nor-BNI, an antagonist of kappa-Opioid receptors and mitoK(ATP) blocker 5-HD attenuated the effect of ischemic/hypoxic postconditioning.

CONCLUSIONPostconditioning may protect myocardium against ischemia/reperfusion injury via activating kappa-Opioid receptors and mitoK(KATP).

Animals ; In Vitro Techniques ; Ischemic Preconditioning, Myocardial ; methods ; L-Lactate Dehydrogenase ; metabolism ; Male ; Myocardial Reperfusion Injury ; metabolism ; physiopathology ; prevention & control ; Myocardium ; metabolism ; pathology ; Potassium Channels ; metabolism ; physiology ; Rats ; Rats, Sprague-Dawley ; Receptors, Opioid, kappa ; metabolism ; physiology

OBJECTIVETo explore the cardioprotection effect of co-treatment with ischemic postconditioning and preconditioning in ischemia/reperfusion (I/R) injury and the related mechanism.

METHODSMale Sprague-Dawley rats were used for Langendorff isolated heart perfusion. The hearts were subjected to global ischemia for 60 min followed by 120 min of reperfusion. The cardiomyocyte viability was measured by MTT-formazan method, and the cardiac injury was evaluated by the levels of lactate dehydrogenase (LDH) in the coronary effluent. Ventricular hemodynamic parameters were also measured.

RESULTIn 60 min of ischemia and 120 min of reperfusion group, ischemic postconditioning increased formazan content, reduced LDH release, but hemodynamic parameters did not improved. Co-treatment with ischemic postconditioning and preconditioning during the prolonged ischemia further improved the hemodynamic parameters. The calcium activated potassium channel antagonist paxilline attenuated the effect of co-treatment with ischemic postconditioning and preconditioning.

CONCLUSIONIschemic postconditioning and preconditioning may synergically protect myocardium from severe ischemia injury, which may be related to calcium-activated potassium channel.

Animals ; Cell Survival ; In Vitro Techniques ; Ischemic Preconditioning, Myocardial ; methods ; L-Lactate Dehydrogenase ; metabolism ; Male ; Myocardial Ischemia ; pathology ; physiopathology ; Myocardial Reperfusion Injury ; metabolism ; physiopathology ; prevention & control ; Myocardium ; metabolism ; pathology ; Potassium Channels, Calcium-Activated ; metabolism ; Rats ; Rats, Sprague-Dawley

To investigate the cardioprotective effect of formononetin (FMN) on no-reflow (NR) after myocardial ischemia-reperfusion and its molecular mechanism based on integrated pharmacology and experimental verification, firstly, human breast cancer MCF-7 cells and myocardial NR rats were used to confirm the estrogenic activity and the effect of alleviating NR of FMN, respectively. Male SD rats were divided into Sham, NR, FMN (20 mg·kg^-1) and sodium nitroprusside (SNP, 5.0 mg·kg^-1) groups, which were administered once a day for one week, the experiment was approved by the Ethics Committee of Tianjin University of Traditional Chinese Medicine (TCM-LAEC2019095). The pharmacological analysis and in vivo study of NR rats were integrated to reveal the mechanism of FMN improving NR. The results showed that FMN had estrogenic effect and reduced NR by improving cardiac structure and function, reducing NR, ischemic myocardial area and pathological injury of cardiomyocytes. Integrated pharmacology predicts that the mechanism of FMN improving NR is mainly related to phosphatidyinositol-3-kinase-protein kinase B (PI3K-Akt) signal pathway. Phytoestrogens play a role in cardiovascular protection mainly by activating G protein-coupled estrogen receptor (GPER). GPER is also an important regulator in the upstream of PI3K-Akt signaling pathway. This study found that FMN can significantly activate GPER, p-PI3K, p-Akt and phospho-endothelial nitric oxide synthase (p-eNOS). It has good binding ability with GPER and eNOS protein. In this study, through the integration of pharmacology and experimental evaluation, it is revealed that FMN activates PI3K/Akt/eNOS signal pathway by activating GPER, thus significantly improving NR.

OBJECTIVES: To study the value of autotaxin (an autocrine motility factor) level in serum and bronchoalveolar lavage fluid (BALF) in predicting refractory Mycoplasma pneumoniae pneumonia (RMPP) in children and its correlation with interleukin-6 (IL-6), interleukin-8 (IL-8), and C-reactive protein (CRP). METHODS: A retrospective analysis was performed on 238 children with Mycoplasma pneumoniae pneumonia who were admitted from January 2019 to December 2021. According to disease severity, they were divided into two groups: RMPP (n=82) and general Mycoplasma pneumoniae pneumonia (GMPP; n=156). The two groups were compared in terms of the levels of autotaxin, IL-6, IL-8, and CRP in serum and BALF to study the value of autotaxin level in serum and BALF in predicting RMPP in children, as well as the correlation of autotaxin level with IL-6, IL-8, and CRP in children with RMPP. RESULTS: Compared with the GMPP group, the RMPP group had significantly higher levels of autotaxin, IL-6, IL-8, and CRP in serum and BALF (P<0.05). For the children with RMPP, the levels of autotaxin, IL-6, IL-8, and CRP in serum and BALF in the acute stage were significantly higher than those in the convalescent stage (P<0.05). The receiver operating characteristic (ROC) curve showed that the level of autotaxin in serum and BALF had a good value in predicting RMPP in children, with an area under the curve of 0.874 (95%CI: 0.816-0.935) and 0.862 (95%CI: 0.802-0.924), respectively. The correlation analysis showed that the level of autotaxin in serum and BALF was positively correlated with IL-6, IL-8, and CRP levels (P<0.001). CONCLUSIONS The level of autotaxin in serum and BALF increases and is correlated with the degree of disease recovery and inflammatory cytokines in children with RMPP. Autotaxin can be used as a predictive indicator for RMPP in children.
C-Reactive Protein ; Child ; Cytokines ; Humans ; Interleukin-6 ; Interleukin-8 ; Mycoplasma pneumoniae ; Pneumonia, Mycoplasma/diagnosis* ; Retrospective Studies

OBJECTIVETo determine whether auricularia auricular polysaccharide (AAP) protects heart against ischemia/reperfusion (1/ R) injury and its underlying mechanisms.

METHODSMale Sprague-Dawley rats, pretreated with AAP (50, 100, 200 mg/(kg x d), gastric perfusion) for 4 weeks, were used for Langendorff isolated heart perfusion. The hearts were subjected to global ischemia for 30 min followed by 120 min of reperfusion and the left ventricular hemodynamic parameters were measured. Formazan, a product of 2, 3, 5-triphenyl-tetrazolium chloride (TTC), which is proportional to myocardial viability, was measured at 490 nm, and the level of lactate dehydrogenase (LDH) in the coronary effluent was measured to evaluate the cardiac injury. The cardiac malondialdehyde (MDA), a product of lipid peroxidation, and superoxide dismutase (SOD) activity were determined after myocardial I/R.

RESULTSThe pretreatment with AAP at 50, 100, 200/(kg d) for 4 weeks before I/R increased myocardial formazan content, reduced LDH release, improved the recovery of the left ventficular developed pressure, maximal rise rate of left ventricular pressure, and rate pressure product (left ventricular developed pressure multiplied by heart rate) attenuated the decrease of coronary flow during reperfusion. The cardiac protective effect of high dose AAP was more potent than that of compound radix salviae miltiorrhizae (CRSM, 4 ml/(kg x d), gastric perfusion for 4 weeks). Pretreatment with AAP (100 mg/(kg x d)) markedly inhibited the increase of MDA level and the decrease of SOD activity induced by I/R in myocardium.

CONCLUSIONThe findings indicate that in the isolated rat heart, AAP protects myocardium against ischemia/reperfusion injury via enhancing the activity of SOD and reducing lipid peroxidation in heart.

Animals ; Basidiomycota ; chemistry ; Male ; Myocardial Ischemia ; pathology ; physiopathology ; Myocardial Reperfusion Injury ; physiopathology ; prevention & control ; Oxidative Stress ; drug effects ; Polysaccharides ; isolation & purification ; pharmacology ; Protective Agents ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Superoxide Dismutase ; metabolism