2.The attenuating effect of ursodeoxycholic acid on endoplasmic reticulum stress-mediated pancreatic β-cell apoptosis in streptozotocin-induced diabetic rats
Min ZHU ; Xing SHI ; Shining NI ; Wei GU ; Mei GUO ; Li FEI ; Xiaoqin PAN ; Qianqi LIU
Chinese Journal of Endocrinology and Metabolism 2011;27(11):935-940
Objective To clarify the protective effect of nrsodeoxycholic acid ( UDCA ) on endoplasmic reticulum stress-mediated apoptosis in pancreatic β-cell of streptozotocin ( STZ )-induced diabetic rats.Methods Rats( n =40) received a single injection STZ( 50 mg/kg) intra-peritoneally and formed a β-cell injury model.Weight-matched normal rats( the control group,n =10 ) were injected with the buffer alone.STZ-treated rats with persistent random blood glucose higher than 16.7 mmol/L for 1 week were considered as diabetic status( n=14 ),then divided randomly into STZ-induced diabetes mellitus ( DM ) group ( n =7 ) and UDCA-treated DM group ( n =7 ).UDCA (40 mg· kg- 1,d-1 ) was administered daily by intragastric intubations throughout the experimental period (30 d).During the entire experiment,blood glucose in all rats was assessed.By the end of the experiment,all rats were sacrificed with the pancreas removed and the blood sample collected immediately.Fasting insulin levels were assayed by radioimmunoassay.The morphological changes of pancreatic β-cells apoptosis were determined by TUNEL assay.RNA in pancreas was abstracted and microarray containing 89 pieces of apoptosis related genes was applied.The related gene expressions were detected by RT-PCR and Western blot.Results The concentration of blood glucose in diabetic rats was gradually decreased after UDCA treatment,but at the end of the experiment it was still higher than that in the normal control group.The treatment with UDCA raised the fasting insulin level in diabetic rats,but this concentration was significantly lower as compared to the control group.Based on TUNEL stained tissue sections,the percentage of β-cell apoptosis of UDCA-treated DM group was significantly lower than that of STZ-induced diabetic group(P<0.05 ).Among 89 genes,42 genes up-regulated and 46 genes down-regulated in diabetic rats,some of which were ameliorated by UDCA treatment.The expressions of Caspase-3,Bax,Bip,and CHOP mRNA in pancreas of DM group were significantly up-regulated as compared with those in the control group ( P < 0.05 ) ; while the expression of Bcl-2 mRNA was markedly down-regulated (P<0.05 ).However,these parameters in the U DCA-treated animals showed a marked improvement.Conclusion Ursodeoxycholic acid seems to protect pancreatic β-cell from apoptosis in STZ-induced diabetes by attenuating the severity of endoplasmic reticulum stress.
3.Effect of curcumin on extracellular matrix accumulation in the glomeruli in nephrotoxic sera nephritis rats
Huaying BAO ; Ronghua CHEN ; Songming HUANG ; Aihua ZHANG ; Mei GUO ; Li FEI ; Xiaoqing PAN
Journal of Integrative Medicine 2004;2(1):30-2
OBJECTIVE: To observe whether curcumin could inhibit the accumulation of the collagen IV and fibronectin in the glomeruli in nephrotoxi sera nephritis rats. METHODS: Seventy-two healthy male Sprague-Dawley rats were divided into three groups, with 24 animals in each group. For normal control group, normal saline (0.5 ml/d) was injected through intra-caudal-vein for two days, and at the same time normal saline (0.5 ml/kg) was also daily administered intraperitoneally. For nephrotoxic sera nephritis group, nephrotoxic sera (0.5 ml/d) was injected through the tail vein for two days and dimethyl sulfoxide (0.5 ml/kg) was given intraperitoneally daily. For curcumin group, nephrotoxic sera was injected as above and meanwhile curcumin (50 mg.kg(-1).d(-1)) was administered intraperitoneally every day. Six rats in each group were killed on the 3rd, 7th, 14th and 28th day. Their renal tissue was fixed in 10% formalin for examining the expression of collagen IV and fibronectin. RESULTS: Minimal staining of collagen IV and fibronectin was detected in the basement membrane of normal control rats glomeruli. In the nephrotoxic sera nephritis rats and curcumin treated nephrotoxic sera nephritis rats, the accumulation of collagen IV and fibronectin was increased progressively, with significant difference in the accumulation of collagen IV (P<0.01) between these two groups at the same time points, while the significant difference in fibronectin accumulation (P<0.05) appeared only after the 7th days. CONCLUSION: Curcumin can reduce the accumulation of collagen IV and fibronectin in the glomeruli. Hence we postulated that curcumin might have beneficial effect for retarding glomerulosclerosis.
4.Contribution of small GTPase Rho effector—Rock-Ⅰin different stages of rat renal interstitial fibrosis
Hua SUN ; Ronghua CHEN ; Wenyan HUANG ; Li FEI ; Mei GUO ; Xiaoqin PAN ;
Chinese Journal of Nephrology 1994;0(02):-
Objective To observe the expression of Rock Ⅰand its functional activation in renal tissue from a rat UUO model, and to investigate its role in the progression of renal interstitial fibrosis(RIF). Methods Expression of RockI mRNA and protein were examined by RT PCR and Western blotting, respectively.The phosphorylation of MBS(binding subunit of myosin phosphatase)—a substrate of Rock Ⅰwas detected by Western blotting and defined,as the mark of functional activation of the kinase. Results (1)The expression of Rock ⅠmRNA was increased before the onset of RIF(the 3rd day after the experiment) (F=15 18,P
5.Effects of heart displacement on hemodynamics during off-pump coronary artery bypass surgery
Wei-Xian ZHAO ; Xiang-Yu LI ; Fei-Peng PAN ; Dong-Mei XIANG ; Yong LI ;
Chinese Journal of Anesthesiology 1997;0(11):-
Objective To investigate the effects of heart displacement on hemodynamics during off-pump coronary artery bypass grafting (OP-CABG) while the sites for anastomosis were being exposed. Methods Forty-seven patients of both sexes (36 male, 11 female) aged 50-82 years undergoing OP-CABG were enrolled in the study. Preoperative cardiac function was assessed : class Ⅱ in 22 patients; Ⅲ in 23 and Ⅳ in 2 according to NYHA classification.The mean ejection fraction was 0.55?0.14 before surgery.They received on average 3.2 grafts. Premedication consisted of intramuscular morphine 10 mg, midazolam 3-5 mg and scopolamine 0.3 mg.Before induction of anesthesia ECG and SpO2 were monitored and radial artery was cannulated for continuous direct BP monitoring. Anesthesia was induced with midazolam 0.1 nig?kg-1 , fentanyl 4?g?kg-1 and pancuronium 0.1 mg?g-1 iv.The patients were mechanically ventilated after tracheal intubation and PETCO2 was maintained at about 40 mm Hg. Anesthesia was maintained with isoflurane and 50%-60% N2O in O2 and intermittent intravenous boluses of fentanyl and pancuronium. Swan-Ganz catheter which can continuously monitor mixed venous blood O2 saturation (SvO2) was placed in pulmonary artery via right internal jugular vein. SvO2, cardiac output (CO), BP, pulmonary arterial pressure (PAP) and HR were continuously monitored. Right atrial pressure (RAP) and PAWP were measured intermittently. Cardiac index (CI),stroke index (SI),systemic vascular resistance index (SVRI),PVRI, left and right ventricular work index (LVWI,RVWI) and left and right ventricular stroke work index (LVSWI,RVSWI) were calculated. The hemodynamic parameters were recorded after induction of anesthesia before surgery (T1,baseline),before heart displacement (T2), while anastomosis to anterior descending branch was being made (T3), while anastonosis to right coronary artery or posterior descending branch (T4) and to left circumflex artery or diagonal branch (T5) was being made, after normal heart position was resumed (T6) and at the end of operation (T7). Results While anastomosis to the anterior descending branch was being made (T3) SI and LVSWI significantly decreased as compared with the baseline (P
6.Mitochondrial derived reactive oxygen species mediates aldosterone-induced epidermal growth factor receptor activation and mesangial cell proliferation
Ying CHEN ; Aihua ZHANG ; Songming HUANG ; Xiaoqin PAN ; Li FEI ; Mei GUO ; Ronghua CHEN
Chinese Journal of Nephrology 2010;26(11):845-850
Objective To detect the signaling pathways involved in aldosterone (ALDO)induced mesangial cell (MC) proliferation. Methods The incorporation of 3H-thymidine (3H-TdR)and cell count were used as the measure of mesangial cell (MC) proliferation. Reactive oxygen species (ROS) production was determined by DCFDA fluorescence. Epidermal growth factor receptor (EGFR) activation was assayed by Western blotting. Results ALDO induced MC proliferation.When incubation with 100 nmol/L ALDO for 24 h, the 3H-TdR incorporation and cell number increased by 2.63- and 2.15-fold, respectively. Mineralocorticoid receptor (MR) antagonist EPLE almost completely blocked ALDO-induced MC proliferation (P<0.01), however, glucocorticoid receptor (GR) antagonist RU-486 had no effect on MC proliferation. ALDO increased intracellular ROS production in cultured human MCs. When incubation with ALDO (100 nmol/L) for 60 min,ROS production increased by 2.14-fold. ALDO-induced ROS generation was completely blocked by EPLE as well as mitochondrial complex Ⅰ inhibitor rotenone (P<0.01=, NADPH oxidase inhibitors diphenyleneiodonium sulfate (DPI) and apocynin inhibited ALDO-induced ROS production by 30%to 35% (P<0.05=. In contrast, inhibitors of other oxidant-producing enzymes, including allopurinol,indomethacin, nordihydroguiaretic acid, ketoconazole and G-nitro-L-arginine methyl ester (L-NAME)had no effect on ALDO-induced ROS production. Antioxidant N-acetyl-L-cysteine (NAC) and ROT inhibited ALDO-induced MC proliferation by 75% to 80%, whereas the inhibition of NADPH oxidase inhibitor apocynin and DPI on ALDO-induced MC proliferation was 25% to 30%. ALDO induced EGFR transactivation. When incubation with 100 nmol/L ALDO for 60 min, EGFR phosphorylation was increased by 4.95-fold, which was completely inhibited by EPLE and antioxidant NAC (P<0.01=. NAC and EGFR antagonist AG1478 significantly blocked ALDO-induced MC proliferation (P<0.01=. Conclusions ALDO-induced MC proliferation is mediated by ROS-dependent EGFR transactivation. ALDO-stimulated ROS is mainly generated by mitochondria.
7.In vitro and in vivo study of fluorescent probe PLGA particles prepared by premix membrane emulsification method.
Tao HU ; Fei-Yan SHI ; Lin-Mei PAN ; Hua-Xu ZHU ; Li-Wei GUO
China Journal of Chinese Materia Medica 2014;39(23):4583-4589
Relatively uniform-sized nanoparticles made of poly (lactic-co-glycolic acid) (PLGA) were prepared by premix membrane emulsification method. After the drug loading property was completed, the dynamic tissue distribution of nanoparticles was recorded. With the average particle size and span as indexes, membrane pore size, number of passing membrane times, membrane pressure, volume ratio of oil-water phase and the concentration of poly(vinyl alcohol) (PVA) in external water phase were investigated by single factor test, the optimum preparation technology of blank PLGA nanlparticles was as following: pore size of SPG membrane was 1 μm, membrane pressure was 1. 15 MPa, the number of passing membrane time was 3, the mass fraction of PVA of 2%, volume ratio of oil-water phase of 1 : 5. Prepared nanoparticles were round with smooth surface, the mean diameter was 332.6 nm, span was 0.010, the confocal laser scanning microscope (CLSM) concluded that fluorescent substance is uniform composizion in PLGA nanoparticle, and the in vivo imaging technology in mice include that the nanoparticles show good liver and spleen targeting property.
Animals
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Drug Carriers
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chemistry
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Drug Delivery Systems
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instrumentation
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Emulsions
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chemistry
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Fluorescent Dyes
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chemistry
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Lactic Acid
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chemistry
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Mice
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Mice, Nude
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Nanoparticles
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chemistry
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Particle Size
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Polyglycolic Acid
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chemistry
8.Preparation of tissue-engineered skin grafts with hTERT cells carrying human papillomavirus type 6 genome in vitro:a preliminary study
Fei WANG ; Zongke GUO ; Hongye ZHANG ; Yongzheng PAN ; Zhengbang DONG ; Mei CHEN ; Ying SHAN ; Qiao YAN ; Weiping YU
Chinese Journal of Dermatology 2015;(5):321-325
Objective To establish a model for preparation of tissue-engineered skin grafts with hTERT cells carrying human papillomavirus type 6 (HPV 6) genome in vitro, so as to lay a foundation for studying HPV life cycle. Methods The full-length linear HPV6 genome and plasmid pEGFP-▲EGFP were electrophoretically cotransferred into hTERT cells. After selection using G418 resistance, Southern blotting was performed to determine the viral load of HPV6 in transfected cells. 3T3 J2 trophoblastic cells, type I rat-tail collagen and hTERT cells containing the full-length HPV6 genes (HPV6.hTERT cells)were mixed and cocultured on metal meshes to form skin graft-like structures. Hematoxylin and eosin (HE)staining was performed to observe the structure of formed skin grafts, an immunohistochemical assay to measure the expression of HPV6 L1 protein, and electron microscopy to observe virus particles in the skin grafts. Results The linear HPV6 gene was successfully transferred into hTERT cells, and Southern blotting showed the presence of HPV6 DNA in the transferred hTERT cells. The HPV6.hTERT cells, which were cocultured with 3T3 J2 trophoblastic cells and type I rat-tail collagen, proliferated and differentiated over time, and gradually formed skin grafts giving the appearance of verrucous hyperplasia. HE staining showed that the cocultured HPV6.hTERT cells could form typical stratified structure of skin after 7 days of cultivation, and histopathologic features of HPV infection, including obvious papillomatous hyperplasia, presence of vesicular cells, hyperkeratosis and parakeratosis, could be observed after 21 days. The immunohistochemical assay showed the expression of HPV6 L1 protein in the upper portion of skin grafts, and electron microscopy revealed the presence of HPV6 virus particles in skin grafts. Conclusions The established model for preparation of tissue-engineered skin grafts using HPV 6 genome-carrying cells provides a basis for biological studies of HPV, but its application is limited to some degree.
9.Preparation and characterization of tetrandrine-loaded PLGA nanocomposite particles by premix membrane emulsification coupled with spray-drying method.
Tao HU ; Hua-Xu ZHU ; Li-Wei GUO ; Lin-Mei PAN ; Bo LI ; Fei-Yan SHI ; Jin LU
Acta Pharmaceutica Sinica 2014;49(11):1607-1613
For effective inhalable dry-powder drug delivery, tetrandrine-PLGA (polylactic-co-glycolic acid) nanocomposite particles have been developed to overcome the disadvantages of nanoparticles and microparticles. The primary nanoparticles were prepared by using premix membrane emulsification method. To prepare second particles, they were spray dried. The final particles were characterized by scanning electron microscopy (SEM), dry laser particle size analysis, high performance liquid chromatography (HPLC), X-ray diffraction (XRD), differential scanning calorimetry (DSC), infrared analysis (IR) and confocal laser scanning microscope (CLSM). The average size of the primary particles was (337.5 ± 6.2) nm, while that second particles was (3.675 ± 0.16) μm which can be decomposed into primary nanoparticles in water. And the second particles were solid sphere-like with the drug dispersed as armorphous form in them. It is a reference for components delivery to lung in a new form.
Administration, Inhalation
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Benzylisoquinolines
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chemistry
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Calorimetry, Differential Scanning
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Drug Delivery Systems
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Dry Powder Inhalers
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Lactic Acid
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chemistry
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Microscopy, Electron, Scanning
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Nanocomposites
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chemistry
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Nanoparticles
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chemistry
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Particle Size
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Pharmaceutical Preparations
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Polyglycolic Acid
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chemistry
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X-Ray Diffraction
10.Resistin Binding Peptide Stimulates Basal Insulin Secretion of RINm5F Insulinoma Cells
Yun-min, ZHANG ; Chun-mei, ZHANG ; Xia, CHI ; Feng, LIU ; Li, FEI ; Xiao-qin, PAN ; Mei, GUO ; Yu-hui, NI ; Rong-hua, CHEN ; Xi-rong, GUO
Journal of Applied Clinical Pediatrics 2008;23(11):879-883
Objective A resistin binding peptide (RBP) was selected by phage display in our previous work. Studies had shown that RBP could antagonize the role of resistin on the lipid metabolism and endocrine function of adipose tissue, but whether RBP affects the insulin secretion of pancreatic cells is still unknown. The aim of this study is to assess the effect of RBP on basal insulin secretion in RINm5F insulinoma cells. Methods The cell viability was measured by 3-[4,5-dimethyhhiazol-2-yl]-2,5-diphenyltetra-zolium bromide (MTT) cytotoxicity assay. The supernatants were assayed for insulin content by enzyme linked immunosorbent assay (ELISA). Reverse transcriptase-PCR assay and Western blotting were used to determine the expression of glucose transporter 2 (GLUT2) involved in insulin secretion. Cytosolic Ca2+, the trigger of insulin exocytosis, was analyzed with the fluorescent probe FURA-3/AM. Results RBP did no effect on the cell viability with a concentration of 10-8-10-12mol/L of 2 hours intervention. But it stimulated basal insulin secretion of RINm5F cells, accompanied by up-regulated increased expression of GLUT2 and elevated concentration of cytosolic Ca2+. Conclusion RBP could stimulate basal insulin secretion without affecting the cell viability.