1.Research progress on Notch signaling pathway and diabetic complications
Bin ZHANG ; Xiangbao MENG ; Yaping CEHN ; Guibo SUN ; Xiaobo SUN
Chinese Pharmacological Bulletin 2016;32(4):463-467
Notch signaling, a highly conserved pathway, is wide-ly found in invertebrates and vertebrates. By mediating cell com-munication, it can regulate many physiological and pathological processes in various kinds of cells, including cell proliferation, differentiation and apoptosis in multi-cellular organism. Accu-mulating evidence shows that abnormality in Notch signaling is highly related to diabetes mellitus and its complications. Accord-ingly, this paper reviews the molecular basis of Notch signaling and the relations between its abnormal expression and diabetes mellitus, and focuses on the impact of key elements in the Notch signaling pathway on diabetic complications as well as correlative mechanisms.
2.Protect effects and the underlying mechanisms of myricitrin against vascular endothelial cells apoptosis induced by oxidative stress.
Guibo SUN ; Meng QIN ; Yun LUO ; Ruile PAN ; Xiangbao MENG ; Min WANG ; Yanhui ZOU ; Xiaobo SUN
Acta Pharmaceutica Sinica 2013;48(4):615-20
This study is to report the study of protective effects of myricitrin against oxidative stress-induced apoptosis of vascular endothelial cells and the investigation of the possible mechanisms of action of myricitrin. The model of H2O2-induced apoptosis of vascular endothelial cells was used to determine the protective effects of myricitrin. The levels of LDH, MDA and the activities of SOD, NO were measured using the respective kits. The H2O2-induced apoptosis of vascular endothelial cells was detected using MTT reduction, TUNEL assay, JC-1 and ROS staining. The activation of Caspase-3 was also measured by fluorometry. The expression of apoptosis-related proteins was determined with Western blotting assay. Myricitrin had significant protective effects against H2O2-induced apoptosis of vascular endothelial cells in a time- and dose-dependent manner. The results show that myricitrin could attenuate H2O2-induced decrease in the activities of SOD (P < 0.01). Myricitrin could decrease the levels of LDH, MDA and increase cell viability and the mitochondrial membrane potential (P < 0.01). Myricitrin had protective effects in a dose-dependent manner between 32 micromol x L(-1) to 64 micromol x L(-1). Myricitrin pretreatment could attenuate H2O2-induced increase of p-ERK. Moreover, myricitrin pretreatment could up-regulate the expression of the anti-apoptotic protein Bcl-2, down-regulate the expression of the pro-apoptotic protein Bax, and decrease the expression of Caspase-3, 9. In conclusion, myricitrin had significant protective effects against H2O2-induced apoptosis of vascular endothelial cells. Myricitrin can enhance the activities of anti-oxidative enzymes and decrease the production of free radicals. The possible mechanisms of action of myricitrin are due to myricitrin-mediated inhibition of phosphorylation of the apoptosis signaling pathways-related kinase ERK, up-regulation of the expression of the anti-apoptotic protein, and down-regulation of the expression of the pro-apoptotic protein.
3.The establishment of animal model with coronary microembolization suitable for long-term observation by using endovascular rnicrocatheter technique
Qingyong ZHANG ; Zhihua WANG ; Xiaobo LI ; Lianhua YIN ; Jingbo LI ; Meng WEI
Journal of Interventional Radiology 2009;18(12):920-922
Objective By using percutaneous endovascular microcatheter technique to establish an animal model of coronary microembolization in mini-swine which is suitable for long-term observation.Methods Coronary microembolization was established in 10 mini-swine by infusing 15 × 10~4 microspheres (φ45μm) selectively into the left anterior descending artery (n = 10). Coronary flow reserve (CFR) was measured by Doppler wire and left ventricular eject fraction (EF) was assessed by echocardiography.Hematoxylin and eosin (HE) staining and nitroblue tetrazolium (NBT) dye were used to demonstrate the presence of microembolization after the procedure of coronary microembolization. The ultra-structures of cardiomyocyte were observed by transmission electron microscopy (TEM). Before sacrifice, the CFR measurement and coronary angiography were performed again in survival animals. Results The coronary microvascular integrity (CFR < 2.0) and left ventricular function (EF < 50% ) were damaged by coronary microembolization. One month after the procedure, all the 10 animals survived and were able to receive the angiography and CFR measurement again. HE staining and NBT dye could demonstrate the presence of microembolization. The edema and fibrosis of cardiomyocytes could be revealed with TEM. Conclusion The animal model of coronary microembolization can be established in mini-swine by using percutaneous endovascular microcatheter technique. The model is suitable for long-term observation, the preparation is technically-simple and minimally-invasive with very low mortality. Therefore, this kind of animal model is an ideal experimental form for studying the mechanism of coronary microembolization.
4.Effects of ginkgolide B on [ Ca~(2+) ]_i and mitochondrial function of cultured rat retinal neurons in vitro
Jing MENG ; Xiaoyan DING ; Xiaobo ZHU ; Shaofen LIN ; Mengxiang GUO ; Shibo TANG
Chinese Journal of Pathophysiology 2009;25(11):2192-2196
AIM: To observe the effect of ginkgolide B (CB) on the intracellular calcium ion concentration ( [ Ca~(2+) ]_i) and mitochondrial function of cultured rat retinal neurons in vitro. METHODS: in vitro primary culture of rat retinal neurons was used in the experiment. The apoptosis model of glutamate - induced retinal neurons was established and co - cultured with ginkgolide B. The [ Ca~(2+) ]_i and mitochondrial membrane potential of the retinal neurons were detected by laser scanning confocal microscope. RESULTS: Glutamate decreased the survival rate of retinal neurons, increased the apoptosis and the [ Ca~(2+) ]_i, lowered the mitochondrial membrane potential. The [ Ca~(2+) ]_i was clearly diminished and the mitochondrial membrane potential was significantly increased with the GB intervention, and the apoptosis decreased significantly. CONCLUSION: GB protects retinal neurons from glutamate induced neurotoxicity. The effect of GB on retinal neurons might be due to its ability to decrease the [Ca~(2+) ]_i and increase mitochondrial membrane potential.
5.Splenic vessels thread ligature in laparoscopic splenectomy
Suolin LI ; Weili XU ; Xiaobo ZHANG ; Meng LI ; Zengwen YU ; Baojun SHI
Chinese Journal of General Surgery 2009;24(10):842-844
Objective To study the anatomy of splenic hilum blood vessels in order to thread ligature(endoligature)instead of using stapler during the process of laparoscopic splenectomy and to evaluate the prelimnary clinical results.Methods 41 children patients underwent laparoscopic splenectomy with this technique(endoligature)for various hematologic and autoimmune disorders,including 25 cases of hereditary spherocytosis,13 idiopathic thrombocytopenia purpura,and 3 hypersplenic granulocytopenia.The anatomy of splenic pedicle,the adjacent relation between splenic vessel and pancreas were detected by color Doppler ultrasonography preoperatively.The above-mentioned parameters were compared with that found intraoperatively.Results The relationships of splenic vessel and pancreas was of type Ⅰ in 24 cases and type Ⅱ in 17.In 31 cases,the major splenic blood vessels were ramified into branches 2 cm away from the hilum and in 10 it was within 2 cm as detected by preoperative ultrasonography.These characters were largerly identified by laparoscopic laparotomy,and in all the 41 cases laparoscopic splenectomy was successfully accomplished using this endoligature instead of vasculature stapler.There was no serious complication.The mean operating time was(114 ±31)min,the estimated blood loss was(51 ±23)ml.Conclusions Ultrasonography could identify the anatomic type of splenic vessel,and its relation with the pancreas.Endoligature in the management of splenic pedicles during laparoscopic splenectomy is safe and reliable.
6.Effect of intrathecal CLP257 on bone cancer pain in rats
Xiaobo QIAN ; Mengwei SHEN ; Jianling GAO ; Li'na WANG ; Xiaowen MENG ; Jianping YANG ;
Chinese Journal of Anesthesiology 2017;37(1):88-91
Objective To investigate the effect of intrathecal CLP257 on the bone cancer pain in rats.Methods Forty adult female Sprague-Dawley rats,weighing 180-200 g,were divided into 4 groups (n=10 each) using a random number table:sham operation group (group S),bone cancer pain group (group BCP),dimethyl sulfoxide (DMSO) group,and CLP257 group.Bone cancer pain was induced by inoculating Walker 256 mammary gland carcinoma cell suspension (about 1× 105cells) 10 μl into the medullary cavity of the left tibia.On 7th-9th days after establishment of the model,5% DMSO 10 μl was injected intrathecally once a day in group DMSO,and 10 μg/μl CLP257 10 μl was injected intrathecally once a day in group CLP257.The mechanical paw withdrawal threshold (MWT) was measured on 1 day before establishment of the model (T0),on 1st-6th days after establishment of the model (T1-6),and at 4 h after intrathecal administration on 7th-9th days after establishment of the model (T7-9).After the last intrathecal administration,the L4-6 segments of the spinal cord were removed for determination of the expression of potassium chloride cotransporter 2 (KCC2) protein and mRNA by Western blot and fluorescent quantitative real-time polymerase chain reaction,respectively.Results Compared with group S,the MWT was significantly decreased,and the expression of KCC2 protein and mRNA was down-regulated in BCP and DMSO groups,and the MWT was significantly decreased (P<0.05),and no significant change was found in the expression of KCC2 protein and mRNA in group CLP257 (P>0.05).Compared with group BCP,the MWT was significantly increased,and the expression of KCC2 protein and mRNA was up-regulated in group CLP257 (P<0.05),and no significant change was found in the parameters mentioned above in group DMSO (P>0.05).Conclusion Intrathecal CLP257 can attenuate the bone cancer pain in rats.
7.Influence of Xinmailong Injection on Isolated Thoracic Aorta of Rats in Different States
Mei LUO ; Xueyu ZHANG ; Weizai SHAO ; Weichong MENG ; Xiaobo LIU ; Lei SHEN
China Pharmacist 2017;20(6):1016-1019
Objective: To study the influence of Xinmailong injection (XML) on the isolated thoracic aorta of rats in different states.Methods: A cumulative dosing method was utilized to evaluate the influence of XML on the isolated thoracic aorta of rats in resting state, and KCl or noradrenaline (NA) induced contracted state.Different tool drugs were used to analyze the mechanism of the effects.Results: Compared with the control group, a specific concentration range of XML could excite the isolated thoracic aorta in resting state, further increase the vascular tension after KCl action, while decrease the vascular tension after NA action.The vasodilative effect of XML on blood vessel after NA action was inhibited by propranolol and diclofenac, while showed no influence from Nω-Nitro-L-arginine.Conclusion: XML has different effects on the isolated thoracic aorta of rats in different states, and the mechanisms of the effects are related to calcium channel, β-receptor and prostaglandins.
8.Effects of ginkgolide B on apoptosis of cultured rat retina neurons in vitro
Jing MENG ; Shibo TANG ; Shaofen LIN ; Jian CHEN ; Xiaobo ZHU ; Tao LI
Chinese Journal of Pathophysiology 1986;0(04):-
AIM: To observe the effect of ginkgolide B (GB) on glutamate-induced apoptosis in the cultured neurons of rat retina. METHODS: Neurons of rat retina were cultured and apoptosis was induced by glutamate. The neurons were cultured with different concentration of GB and the survival rate was monitored by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. The apoptosis in the cultured neurons and the expression of Bcl-2 and Bax were observed by flow cytometry. RESULTS: After exposed to glutamate, the survival rate and the number of Bcl-2 positive cells obviously decreased. At the same time, the number of Bax positive cells obviously increased, and the number of the apoptotic cells also obviously increased. Such phenomena were relieved by the treatment of ginkgolide B, with raise of survival rate and the expression of Bcl-2. Meanwhile, the expression of Bax and the apoptosis of neurocytes obviously decreased. CONCLUSIONS: Ginkgolide B protects retinal neurons from the virulence induced by glutamate. Such effects of GB might be brought about by increasing the expression of Bcl-2 while decreasing Bax, resulting in increasing the ratio of Bcl-2 to Bax and so reducing the apoptosis in the cultured neurons of rat retina.
9.Protective effect of Panax Notoginseng Saponins of Nrf2 signaling pathway on apoptosis of PC12 cells induced by Aβ25-35
Jingyu ZHAO ; Mengxia WANG ; Ziming ZHAO ; Xiangbao MENG ; Guibo SUN ; Xiaobo SUN
Chinese Pharmacological Bulletin 2016;32(3):343-348,349
Aim To investigate the protective effect of Panax Notoginseng Saponins ( PNS ) on Aβ25-35-in-duced apoptosis in PC12 cells and molecular mecha-nism. Methods The cell viability of PC12 cells was detected by MTT assay. The levels of LDH leakage, ROS,MDA,Caspase-3 activity and antioxidant enzyme activities of SOD, CAT, and GSH-Px activity were de-termined by respective kits. The apoptosis of cells was decteced by Western blot. Results PNS could signifi-cantly inhibit the decrease of cell viability and LDH leakage, reduce the production of MDA and ROS( P<0. 01), increase the activity of SOD,CAT and GSH-Px ( P <0. 01 ) , and the mitochondrial membrane poten-tial, inhibit the activation of caspase-3 ( P <0. 01 ) in PC12 cells which were induced by Aβ25-35 . PNS could incrase nuclear Nrf2 and up-regulate HO-1 . The neu-roprotective of PNS could be inhibited by HO-1 inhibi-tor ZnPP. Conclusion PNS may inhibit Aβ25-35-in-duced oxidative stress and apoptosis in PC12 cells by activating Nrf2/HO-1 signaling pathway.
10.Transition mutations in 23SrRNA in ureaplasma urealytlcum account for acquired resistance to macrolides
Dongya MENG ; Xiaobo MA ; Li HE ; Chunling ZHANG ; Lu WANG ; Wencheng XUE
Chinese Journal of Laboratory Medicine 2008;31(6):653-656
Objective To investigate the mechanisms of ureaplasma urealyticum(Uu)resistance to macrolide antibiotics.Methods Twenty strains of clinical isolates of Uu with variable resistance to macrolides and reference strain ATCC 27618 were examined for mutations in 23SrRNA.Results As compared with the sequence of reference strain ATCC 27618 and GenBank,three mutations were found in 23SrRNA of Uu clinical isolates.C2243N(TorC)was found in the 23SrRNA in 5 strains with the phenotype resistance to roxithromvcin and azithromycin.A2149C and A2181T were found in the 23SrRNA in 9 strains with the phenotype resistance to roxithromycin and midrange resistance to azithromycin,and 6 strains with the phenotype of sensitivity to roxithromyein and azithromycin.Conclusions The mechanisms of Uu resistance to roxithromycin and azithromycin may be related with the mutations in 23SrRNA.It may warrant further investigation.