Kunming Medical College
Kunming Medical College
Wu J.,Kunming Medical College |
Ma D.L.,National University of Singapore |
Ling E.A.,National University of Singapore |
Tang F.R.,National University of Singapore
Neuroscience Letters | Year: 2012
We investigated the cellular localization and progressive changes of corticotropin releasing factor (CRF) in the mouse hippocampus, during and after pilocarpine induced status epilepticus (PISE) and subsequent epileptogenesis. We found that CRF gene expression was up-regulated significantly at 2. h during and 1. d after PISE in comparison to control mice. Immunohistochemical analysis showed that the number of CRF and Fos immunoreactive cells was increased significantly in the strata oriens and pyramidale of CA1 area and in the stratum pyramidale of CA3 area at 2. h during and 1. d after PISE. CRF was induced in calbindin (CB) or calretinin (CR) immunoreactive interneurons in stratum oriens at 2. h during PISE. It suggests that induced CRF may be related to the over excitation of hippocampal neurons and occurrence of status epilepticus. It may also cause excitoneurotoxicity and delayed loss of CA3 and CA1 pyramidal neurons, leading to the onset of epilepsy. © 2012 Elsevier Ireland Ltd.
Cao Q.,National University of Singapore |
Li P.,Kunming Medical College |
Lu J.,Defence Medical and Environmental Research Institute |
Dheen S.T.,National University of Singapore |
And 2 more authors.
Journal of Neuroscience Research | Year: 2010
Microglial cells constitutively express Notch-1 and nuclear factor-κB/p65 (NF-jB/p65), and both pathways modulate production of inflammatory mediators. This study sought to determine whether a functional relationship exists between them and, if so, to investigate whether they synergistically regulate common microglial cell functions. By immunofluorescence labeling, realtime polymerase chain reaction (RT-PCR), flow cytometry, and Western blot, BV-2 cells exhibited Notch-1 and NF-κB/p65 expression, which was significantly upregulated in cells challenged with lipopolysaccharide (LPS). This was coupled with an increase in expression of Hes-1, tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β). In BV-2 cells pretreated with N-[N-(3,5-difluorophenacetyl)-1-alany1]-S-phenyglycine t-butyl ester (DAPT), a γ-secretase inhibitor, followed by LPS stimulation, Notch-1 expression level was enhanced but that of all other markers was suppressed. Additionally, Hes-1 expression and NF-κB nuclear translocation decreased as shown by flow cytometry. Notch-1's modulation of NF-κB/p65 was also evidenced in amoeboid microglial cells (AMC) in vivo. In 5-day-old rats given intraperitoneal injections of LPS, Notch-1, NF-κB/ p65, TNF-α, and IL-1β immunofluorescence in AMC was markedly enhanced. However, in rats given an intraperitoneal injection of DAPT prior to LPS, Notch-1 labeling was augmented, but that of TNF-α and IL-1β was reduced. The results suggest that blocking of Notch-1 activation with DAPT would reduce the level of its downstream end product Hes-1 along with suppression of NF-κB/p65 translocation, resulting in suppressed production of proinflammatory cytokines. It is concluded that Notch-1 signaling can trans-activate NF-κB/p65 by amplifying NF-κB/p65-dependent proinflammatory functions in activated microglia. © 2010 Wiley-Liss, Inc.
Li F.,Kunming Medical College |
Wang L.,Kunming Hai Yuan Medical College |
Li J.-W.,Kunming Hai Yuan Medical College |
Gong M.,Kunming Medical College |
And 4 more authors.
BMC Neuroscience | Year: 2011
Background: Activation of amoeboid microglial cells (AMC) and its related inflammatory response have been linked to the periventricular white matter damage after hypoxia in neonatal brain. Hypoxia increases free ATP in the brain and then induces various effects through ATP receptors. The present study explored the possible mechanism in ATP induced AMC activation in hypoxia.Results: We first examined the immunoexpression of P2X4, P2X7 and P2Y12 in the corpus callosum (CC) and subependyma associated with the lateral ventricles where both areas are rich in AMC. Among the three purinergic receptors, P2X4 was most intensely expressed. By double immunofluorescence, P2X4 was specifically localized in AMC (from P0 to P7) but the immunofluorescence in AMC was progressively diminished with advancing age (P14). It was further shown that P2X4 expression was noticeably enhanced in P0 day rats subjected to hypoxia and killed at 4, 24, 72 h and 7 d versus their matching controls by double labeling and western blotting analysis. P2X4 expression was most intense at 7 d whence the inflammatory response was drastic after hypoxia. We then studied the association of P2X4 with cytokine release in AMC after hypoxic exposure. In primary microglial cells exposed to hypoxia, IL-1β and TNF-α protein levels were up-regulated. Blockade of P2X4 receptor with 2', 3'-0-(2, 4, 6-Trinitrophenyl) adenosine 5'-triphosphate, a selective P2X1-7 blocker resulted in partial suppression of IL-1β (24% vs hypoxic group) and TNF-α expression (40% vs hypoxic group). However, pyridoxal phosphate-6-azo (benzene-2, 4-disulfonic acid) tetrasodium salt hydrate, a selective P2X1-3, 5-7 blocker did not exert any significant effect on the cytokine expression.Conclusions: It is concluded that P2X4 which is constitutively expressed by AMC in postnatal rats was enhanced in hypoxia. Hypoxia induced increase in IL-1β and TNF-α expression was reversed by 2', 3'-0-(2, 4, 6-Trinitrophenyl) adenosine 5'-triphosphate suggesting that P2X4 mediates ATP induced AMC activation and its production of proinflammatory cytokines. © 2011 Li et al; licensee BioMed Central Ltd.
Cao Q.,National University of Singapore |
Kaur C.,National University of Singapore |
Wu C.-Y.,Kunming Medical College |
Lu J.,Defense Medical and Environmental Research Institute |
Ling E.-A.,National University of Singapore
Neuroscience | Year: 2011
Microglial cells exhibit Notch-1 signaling expression which is enhanced upon activation. We reported previously that enhanced Notch-1 expression in activated microglia modulates production of proinflammatory cytokines and nitric oxide (NO). Furthermore, Notch-1 modulates transcription factor nuclear factor-kappa B (NF-κB). This study was aimed to investigate if NF-κB reciprocally modulates Notch signaling in BV-2 cells. In this connection, the cells were pretreated with caffeic acid phenethyl ester (Cape) followed by stimulating the cells with lipopolysaccharide (LPS). Cape+LPS treatment resulted in reduced translocation of NF-κB into the nucleus. Concomitantly, NF-κB DNA binding activity and the mRNA and protein expression levels of NF-κB/p65, Notch-1, intracellular domain of Notch-1 receptor (NICD), Hes-1, tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β) and inducible nitric oxide synthase (iNOS) along with nitrite level were significantly reduced. Additionally, flow cytometry analysis showed a decrease in expression levels of NF-κB/p65, Notch-1, NICD but an increase in that of signal transducers and activators of transcription 3 (Stat3). Furthermore, nuclear Hes-1, phosphorylated Stat3 (p-Stat3) and recombination signal-binding protein 1 for J-Kappa (RBP-JK) expression levels were significantly suppressed. The present results suggest that Cape inhibits NF-κB activation through suppressing its interaction with DNA. Cape-induced reduction of Hes-1 may be attributed to decreased interaction between NICD and RBP-JK whose levels were reduced concurrently. Hes-1 reduction may lead to decreased production of inflammatory cytokines and NO. It is concluded that NF-κB can modulate Notch-1 signaling. Both pathways operate synergistically for production of proinflammatory cytokines and NO in activated microglia. © 2011 IBRO.
Xiao X.L.,Xi'an Jiaotong University |
Ma D.L.,National University of Singapore |
Wu J.,Kunming Medical College |
Tang F.-R.,National University of Singapore
Brain Research | Year: 2013
Metabotropic glutamate receptor 5 (mGluR5) is involved in neural stem cell self-renewal, proliferation, differentiation and survival. In this study, we aimed to further determine the role of mGluR5 in the development of hippocampus using mGluR5 deficit (mGluR5-/-) and wild type (mGluR5+/+) mice at different developmental ages. We showed that the number of BrdU, NeuroD and DCX immunopositive cells was reduced significantly in mGluR5-/- than in mGluR5+/+ mice from postnatal 7 days (P7) to P28, but not at P60. The length and intensity of DCX immunopositive apical dendrites in the dentate gyrus of mGluR5-/- mice were much shorter and lower than in mGluR5+/+ mice respectively at P14, P21 and P28. NeuN immunostaining indicated an accelerated maturation of hippocampal neurons in mGluR5 -/- mice. When mGluR5+/+ mice were treated with 2-methyl-6-(phenylethynyl) pyridine (MPEP), a selective antagonist of mGluR5, decreased proliferation of progenitor cells was observed in the hippocampus at early postnatal developmental stages. At P14, there were more BrdU+ cells in the stratum granulosum and subgranular layer of the dentate gyrus in mGluR5+/+ than in mGluR5-/- mice, but the percentage of BrdU++NeuroD+/BrdU+ in the dentate gyrus did not change significantly between the two genotypes of mice. Western Blot study suggested that programmed neuronal death was p53-dependent apoptosis in the developmental hippocampus in mGluR5+/+ mice. © 2012 Elsevier B.V.
Li V.C.,University of California at Los Angeles |
Wang Q.,Yuxi Municipality Bureau of Agriculture |
Xia N.,Yuxi Municipality Bureau of Agriculture |
Tang S.,Kunming Medical College
American Journal of Public Health | Year: 2012
In China, approximately 20 million farmers produce the world's largest share of tobacco. Showing that income from crop substitution can exceed that from tobacco growth is essential to persuading farm families to stop planting tobacco, grown abundantly in Yunnan Province. In the Yuxi Municipality, collaborators from the Yuxi Bureau of Agriculture and the University of California at Los Angeles School of Public Health initiated a tobacco crop substitution project. At 3 sites, 458 farm families volunteered to participate in a new, for-profit cooperative model. This project successfully identified an approach engaging farmers in cooperatives to substitute food crops for tobacco, thereby increasing farmers' annual income between 21% and 110% per acre.
Lima M.J.,University of Aberdeen |
Docherty H.M.,University of Aberdeen |
Chen Y.,University of Aberdeen |
Chen Y.,Kunming Medical College |
Docherty K.,University of Aberdeen
Molecular and Cellular Endocrinology | Year: 2012
The AR42J-B13 rat pancreatic acinar cell line was used to identify pancreatic transcription factors and exogenous growth factors (GFs) that might facilitate the reprogramming of exocrine cells into islets. Adenoviruses were used to induce exogenous expression of the pancreatic transcription factors (TFs) Pdx1, MafA, Ngn3 and Pax4. Individually Pdx1, MafA and Pax4 had no effect on the expression of endocrine markers, whilst adeno-Ngn3 on its own increased the expression of Pax4, Ngn3 and NeuroD. In combination the four TFs had a significant effect on the expression of insulin 1 and 2 that was associated with a change in cell morphology from a rounded to a spindle-like shape. Amongst a range of growth factors, Betacellulin and Nicotinamide were shown to enhance the effects of the four TFs. The presence of adeno-Pax4 in the differentiation cocktail was important in limiting the expression of glucagon and in generating glucose sensitive insulin secretion. Further experiments asked whether the adenoviral TFs could be replaced by protein transduction domain (PTD)-containing TFs. The results showed that the PTD-TFs could mimic in part the effects of the adeno-TFs, but the resultant cells did not undergo the important morphological change associated with differentiation to endocrine lineages and levels of endogenous markers were very much lower. In summary, the results describe a cocktail of four TFs and two GFs that can be used to induce formation of glucose sensitive insulin secreting cells from ARJ42 cells, and demonstrate that it would be difficult to replace adenoviral transduction with PTD-TFS. © 2012 Elsevier Ireland Ltd.
Shen L.J.,Kunming Medical College
Zhonghua gan zang bing za zhi = Zhonghua ganzangbing zazhi = Chinese journal of hepatology | Year: 2010
To investigate the roles of p38 MAPK in apoptosis of the normal liver cell, the paratumor cirrhosis hepatocellular cell and the hepatocellular carcinoma cell. Three cell lines were adopted (the normal liver cell line HL-7702, the paratumor cirrhosis hepatocellular cell line QSG-7701 and the hepatocellular carcinoma cell line QGY-7703) and treated with Diamminedichloroplatin (DDP, cisplatin) and p38MAPK inhibitor SB203580. The apoptosis and cell cycles were detected by flow cytometry and electromicroscopy. The expressions of p38MAPK, CDC25B, p34cdc2 and cyclinB1 were detected by immunocytochemical staining , confocal microscopy and western blot. The apoptotic rates in all three cell lines pretreated with DDP increased obviously and the rates in normal liver cells and HCC cells increased continuously even after SB203580 treatment, whereas in paratumor cirrhosis cells the rate decreased and the cell cycle stopped at S phase. Cisplatin induces apoptosis in the paratumor cirrhosis hepatocellular cell line QSG-7701 via activation of p38MAPK pathway and it differs in the normal liver cells from the hepatocellular carcinoma cells.
Zeng J.,Kunming Medical College
Zhongguo ji sheng chong xue yu ji sheng chong bing za zhi = Chinese journal of parasitology & parasitic diseases | Year: 2011
To investigate the therapeutic efficacy of ginsenoside Rg3 on hepatic fibrosis in murine schistosomiasis japonica. 54 ICR-strain male mice were divided into 4 groups named as normal control group (A), infected control group (B), praziquantel+Rg3 treated group (C) and praziquantel treated group (D). There were 12 mice in each group, but 18 in group A. Mice in groups B, C, and D were infected with 20 +/- 2 cercariae of Schistosoma japonicum. At ten weeks post-infection, 10 mice of group A and 12 mice of group B were weighed and sacrificed. Specimens from left hepatic lobes were taken and fixed in 10% formaldehyde solution. Mice in groups C and D were treated intragastrically with praziquantel at a single dose of 300 mg/kg. At the second day after praziquantel treatment, each mouse in group C was given 3 mg/(kg x d) ginsenoside Rg3 for 8 weeks. The rest mice were sacrificed on 8 weeks after treatment, and liver tissue samples from left hepatic lobes were prepared. The histological changes and collagen fiber deposition in the liver tissue sections were observed with hematoxylin-eosin staining and van gieson staining. Liver fibrosis was graded according to semi-quantitative scoring system (SSS) method. In group B, many eggs deposited in the hepatic lobules and portal areas, and eosinophilic abscesses and pseudo-tubercles developed in the liver, especially common in portal areas. There were many fibre hyperplasia and deposit inside abbacy and liver flocculus. Pipestem fibrosis formed around the portal areas, and some cord-like fibres extended into hepatic lobules, and formed in the fibrous septa. After 8-week treatment with ginsenoside Rg3, in group C, the livers were initially enlarged, firm and dust-color; and the degree of hepatomegaly varied from mild to marked; but the degree of fibre hyperplasia and inflammatory infiltration were mitigated compared with that of group B. Mean percentage of collagen area in group C [(2.32 +/- 0.99)%] was lower than that of groups B [(11.08 +/- 4.43)%] and D [(11.19 +/- 4.91)%] (P < 0.05). The SSS scores of hepatic fibrosis in group C (2.83 +/- 1.09) was lower than that of groups B (7.42 +/- 1.16) and D (8.08 +/- 1.76) (P < 0.05). Ginsenoside Rg3 shows anti-hepatofibrosis effects in murine schistosomiasis japonica after praziquantel treatment.
Qi J.L.,Kunming Medical College
Zhonghua liu xing bing xue za zhi = Zhonghua liuxingbingxue zazhi | Year: 2012
To understand the status of HIV sexual transmission among HIV-sero-discordant spouses and HIV-sero-accordant spouses in Yunnan province, to discuss the related factors and to provide evidence for HIV prevention and control strategy. Five places with serious epidemic and 3 moderate ones were voluntarily, randomly selected. According to time sequence, 300 spouses (600 people) with stable marriage were interviewed with questionnaire. HIV-sero-accordant spouses occupied for 40.7% of the total spouses under survey, with the others were HIV-sero-discordant ones. Among the ones that had already been diagnosed in the families, sexual transmission was their main mode of transmission, which was accounted for 68.3%, followed by IDU as 19.7%. After disclosed the HIV test outcomes to their spouses, 63.4% HIV-sero-discordant spouses and 47.0% HIV-sero-accordant ones changed their sexual behaviors. The rates of consistent condom use among the HIV-sero-discordant spouses increased from 16.8% to 95.0%, and in HIV-sero-accordant spouses increased from 8.2% to 60.9%. Data were analyzed by multi-factor logistic regression. Factors on influencing the sexual transmission in spouses would include condom use, frequency of sexual contacts and sexual transmission disease (STD) status etc. The main transmission mode for the first HIV infected spouse was sexual transmission. Factors influencing sexual transmission in spouses would include condom use, frequency of sexual contacts, STD situation and husband was the first one being infected in the families, etc. Disclosure of the HIV results to the spouses could make a significant changes in the frequencies of sexual contact as well as the rate of condom use.