1.Establishment of perfusion technique for isolated rat pancreas
Nai-Qian ZHAO ; Ye-Rong YU ; Hui-Wen TAN ; Zhi-Ming LU ; Xiang-Xun ZHANG ; Jun-Jie LI ;
Chinese Journal of Endocrinology and Metabolism 2001;0(05):-
Objective To establish an isolated rat pancreas perfusion technique,a method for the precise measurement of insulin secretion in vitro.Methods An isolated rat pancreas perfusion technique was applied in the study of insulin secretion from?-cells in 10 high-fat diet-induced obese Wistar rats.Results For the assessment of the functional integrity of the perfused pancreas,the isolated pancreas of 6 rats met all the criteria: (1)The constancy of perfusion pressure was kept over the whole experiment time[(70?5)mm Hg,1 mm Hg= 0.133 kPa].(2)The duodenal peristaltic activity of isolated pancreas and duodenum block was present after perfusion experiment.(3)Total insulin response to arginine stimulation was significantly increased as compared with glucose stimulation[maximum insulin secretion rate:(987?100)?U/min vs(545?50)?U/min,P
2.Study on the status of institutional delivery and its determinants in rural Guangxi autonomous region.
Jian LI ; Li-Li CHEN ; Shu-Zhen CHEN ; Ming-Yang CEN ; Nai-Qing ZHAO ; Xu QIAN
Chinese Journal of Epidemiology 2008;29(3):224-229
OBJECTIVETo understand the situation of institutional delivery of rural pregnant women in Guangxi Autonomous Region in the period of 1998 - 2003 and to identify the determinants on institutional delivery utilization.
METHODSUsing Andersen's behavioral model as analytical framework and Guangxi databank of the 3rd National Health Service Survey as data source, we described the status of institutional delivery with the rural women having had live birth history in the period of 1998 - 2003 as subjects, while and the univariate analysis and multivariate logistic analysis were done to identify determinants of institutional delivery utilization.
RESULTSAmong a total number of 407 women with live birth history, 39.80 percent of them delivered at the health-care facilities. The rate of institutional delivery increased annually in 1998 - 2003 (P< 0.0001). The proportion of delivery in township health centers increased and the proportion of home delivery decreased by year (P< 0.0001). Results from both univariate and multivariate analysis showed that parity, education background of women, type of drinking water, time needed to get to the nearest healthcare facilities by the most convenient traffic,frequency of prenatal checkup, together with whether or not being advocated on institutional delivery etc. were determinants of delivery utilization. The OR value were 1.749 for multipara, 1.995 for those going to the nearest healthcare facilities by the most convenient traffic in less than 10 minutes, 3.011 for those drinking tap water, 5.435 for those with the education of high school, 29.149 for those with over 5 times in terms of frequency of prenatal checkup and 37.822 for those being advocated on institutional delivery.
CONCLUSIONSocio-economic situation, status of maternal health care and parity made main contribution to institutional delivery and skilled birth attendance for women in rural Guangxi.
China ; Choice Behavior ; Delivery, Obstetric ; methods ; utilization ; Female ; Hospitalization ; statistics & numerical data ; Humans ; Models, Statistical ; Pregnancy ; Rural Population
3.Role of apoptosis and mitochondrial apoptotic pathway in glucolipotoxicity-induced islet beta-cell dysfunction.
Nai-Qian ZHAO ; Ye-Rong YU ; Hui-Wen TAN ; Gang DENG ; Xiang-Xun ZHANG
Journal of Southern Medical University 2008;28(11):2009-2013
OBJECTIVETo investigate the mechanism of beta-cell dysfunction induced by glucolipotoxicity in high fat-fed obese rats.
METHODSEighteen high-fat obese male Wistar rats were assigned into 3 groups and underwent 48-hour infusion through the jugular vein with normal saline (n=6), 20% intralipid + heparin (FFA group, n=6), or 25%glucose +20% intralipid + heparin (GS-FFA group, n=6). The plasma beta-hydroxybutyric acid (beta-HBA) was measured before and at the end of the infusion. After the infusion, the rats were sacrificed following an intravenous glucose tolerance test (IVGTT) to remove the tail of the pancreas for detection of apoptotic islet cells using TUNEL method. Immunohistochemical staining was performed to detect the expression of cytochrome c (cyt c), apoptosis-inducing factor (AIF), caspase-9 and caspase-3 in the islet cells.
RESULTSAt the end of the infusion, all the rats exhibited increased plasma beta-HBA levels, which was the highest in the GS-FFA group (P<0.05). IVGTT performed after the infusion showed a significantly lower insulinogenic index in GS-FFA group than that in NS and FFA groups. Greater number of apoptotic islet cells was found in the GS-FFA group than in the FFA and NS groups (P<0.05), and the islets had significantly higher levels of cyt c, AIF, caspase-9 and caspase-3 in the former group than in the latter two groups (P<0.05).
CONCLUSIONSHyperglycemia and high free fatty acid level synergistically impair insulin secretions to cause ketone overproduction in high fat-fed obese rats. The beta-cell dysfunction due to glucolipotoxicity is associated with increased beta-cell apoptosis and activation of mitochondrial apoptotic pathway.
3-Hydroxybutyric Acid ; blood ; Animals ; Apoptosis ; drug effects ; Fat Emulsions, Intravenous ; pharmacology ; Glucose ; pharmacology ; Glucose Tolerance Test ; Insulin-Secreting Cells ; cytology ; pathology ; Male ; Mitochondria ; drug effects ; Obesity ; physiopathology ; Rats ; Rats, Wistar
4.Advances in immunotherapy of Alzheimer's disease with traditional Chinese medicine
Sha-sha WANG ; Zhao ZHANG ; Xin ZHANG ; Qian LONG ; Wen-bin HE ; Nai-hong CHEN
Acta Pharmaceutica Sinica 2018;53(7):1023-1029
Alzheimer's disease (AD) is a type of common neurodegenerative disease. The main clinical symptom of the disease is progressive cognitive dysfunction, which has no effective therapy yet. With the in-depth immunology study in the central nervous system, studies in different fields such as preclinical phase, genetics and bioinformatics have shown that immune dysfunction contribute to the pathogenesis of AD, including the beginning, maintenance and deterioration stage in AD. China has a wealth of natural medicine resources and clinical experiences. A large number of natural drugs and effective components both can regulate the immune function and ameliorate the symptoms in AD. This review summarizes the researches of ameliorating the symptoms in AD through immunization regulation in recent years with an aim to provide new ideas and clues in the study of new anti-AD drugs using natural medicines.
5. Prediction of T cell and B cell epitopes of the 22-, 47-, 56-, and 58-kDa proteins of Orientia tsutsugamushi
Li-Na NIU ; Ting-Ting FU ; Yu-Ying DONG ; Zi-Hao WANG ; Si-Qi WANG ; Xuan ZHAO ; Nai-Xu HOU ; Qiang WU ; Qian CHEN ; Man-Ling CHEN ; Jin-Chun TU ; Li-Na NIU ; Qiang WU
Asian Pacific Journal of Tropical Biomedicine 2019;9(10):443-448
Objective: To predict B cell and T cell epitopes of 22-kDa, 47-kDa, 56-kDa and 58-kDa proteins. Methods: The sequences of 22-kDa, 47-kDa, 56-kDa and 58-kDa proteins which were derived from Orientia tsutsugamushi were analyzed by SOPMA, DNAstar, Bcepred, ABCpred, NetMHC, NetMHC II and IEDB. The 58-kDa tertiary structure model was built by MODELLER9.17. Results: The 22-kDa B-cell epitopes were located at positions 194-200, 20-26 and 143-154, whereas the T-cell epitopes were located at positions 154-174, 95-107, 17-25 and 57-65. The 47-kDa protein B-cell epitopes were at positions 413-434, 150-161 and 283-322, whereas the T-cell epitopes were located at positions 129-147, 259-267, 412-420 and 80-88. The 56-kDa protein B-cell epitopes were at positions 167-173, 410-419 and 101-108, whereas the T-cell epitopes were located at positions 88-104, 429-439, 232-240 and 194-202. The 58-kDa protein B-cell epitopes were at positions 312-317, 540-548 and 35-55, whereas the T-cell epitopes were located at positions 415-434, 66-84 and 214-230. Conclusions: We identified candidate epitopes of 22-kDa, 47-kDa, 56-kDa and 58-kDa proteins from Orientia tsutsugamushi. In the case of 58-kDa, the dominant antigen is displayed on tertiary structure by homology modeling. Our findings will help target additional recombinant antigens with strong specificity, high sensitivity, and stable expression and will aid in their isolation and purification.
6.ox-LDL Promotes Bidirectional Regulation of Neuronal Apoptosis Through The PCSK9/LRP1 Signaling Pathway
Nai-Qi HE ; Xue-Shan ZHAO ; Qian XU ; Hua-Yu ZHANG ; Zhong REN ; Zhi-Han TANG ; Qiong XIANG ; Lu-Shan LIU
Progress in Biochemistry and Biophysics 2024;51(4):944-958
Obiective Alzheimer’s disease (AD) is a degenerative disease of the central nervous system (CNS) caused by a variety of risk factors. There are various pathological changes, but apoptosis of the neurological meridian cells is one of the most important pathological bases. Hyperlipidemia is a high-risk factor for the development of AD, which can lead to increased levels of oxidized low-density lipoprotein (ox-LDL) in brain tissues. PCSK9 is a protease closely related to lipid metabolism, but studies have shown that it may be related to the development of AD. LRP1 is abundantly expressed in neuronal cells, and it is an important transporter for the clearance of Aβ. There is now a large amount of literature confirming that PCSK9 can induce the degradation of LRP1. PI3K/AKT is an important signaling pathway in vivo, which plays an important role in apoptosis, and there is now a large amount of literature confirming that LRP1 activates the PI3K/AKT pathway, which has an anti-apoptotic effect. So can PCSK9 affect the PI3K/AKT pathway through LRP1 and thus regulate neuronal apoptosis? This deserves further investigation.The aim of this study was to explore the role of PCSK9 in mediating ox-LDL pro-apoptotic neuronal cell death and its mechanism, and then further elaborate the mechanism of hyperlipidemia leading to neurodegenerative diseases such as AD. MethodsFirstly, PC12 cells were treated with different concentrations of ox-LDL (0, 25, 50, 75 and 100 mg/L) for 24 h. Oil red O staining was used to detect lipid accumulation in PC12 cells, Hoechst33258 staining and flow cytometry to detect apoptosis in PC12 cells, ELISA to detect the content of Aβ secreted by PC12, Western blot to detect expression of SREBP2, PCSK9 and LRP1. Then PC12 cells were treated with 75 mg/L ox-LDL for different times (0, 6, 12, 24, 48 h), and Western blot were performed to detect the expression of SREBP2, PCSK9 and LRP1. Finally, after transfecting 100 nmol/L PCSK9 siRNA into PC12 cells for 48 h, PC12 cells were treated with 75 mg/L ox-LDL for 24 h, Hoechst33258 staining and flow cytometry to detect apoptosis rate of PC12 cells, and Western blot to detect PCSK9, LRP1, PI3K, AKT, P-PI3K , P-AKT, NF-κB, Bcl-2, Bax, Caspase-9 and Caspase-3 expression, and ELISA detected Aβ content secreted by PC12 cells. Resultsox-LDL increased lipid accumulation and promoted apoptosis and Aβ secretion in PC12 cells, as well as increasing the expression of SREBP2 and PCSK9 and decreasing the expression of LRP1 in PC12 cells. pCsk9 siRNA could be inhibited through the PI3K/AKT pathway and the NF-κB-Bcl-2/Bax-Caspase-9/3 pathway to inhibit ox-LDL-induced apoptosis in PC12 cells while increasing Aβ secretion in PC12 cells. Conclusionox-LDL plays a bidirectional regulatory role in ox-LDL-induced apoptosis of PC12 cells by inducing an increase in PCSK9 expression and a decrease in LRP1 expression in PC12 cells, which in turn affects different signaling pathways downstream.