A role for the parafascicular thalamic nucleus in the development of morphine dependence and withdrawal.

The parafascicular thalamic nucleus (nPf) is a critical relay in the ascending system that mediates motor control in the central nervous system (CNS). Yet, little is known about whether or not the nPf is involved in the development of morphine dependence and withdrawal. In the present study, kainic acid was used to chemically destroy the nPf in Wistar rats, and morphine dependence and withdrawal models were established. Morphine withdrawal symptoms score was evaluated in each group. An electrophysiological method was used to measure the changes in spontaneous discharge of nPf neurons. mu-Opioid receptor (MOR) mRNA level in nPf was detected using semi-quantitative RT-PCR. The ultrastructural alterations were examined by transmission electron microscopy. Results showed that the bilateral lesion of nPf had a marked influence on the development of morphine dependence and withdrawal. In order to address the mechanisms underlying, we found: (1) the average frequency and sum of nPf neurons that exhibited spontaneous discharge were increased in the morphine withdrawal group in comparison with the sham model group (P<0.05); (2) MOR mRNA level in the nPf of the morphine dependence group was decreased in comparison with that of the sham model group (1.45+/-0.38 vs. 5.37+/-0.94, P<0.01). In the morphine withdrawal group, which underwent 40 h withdrawal, the MOR mRNA level was higher than that in the morphine dependence group (2.97+/-0.73 vs. 1.45+/-0.38, P<0.05) but still lower than that in the sham model group (P<0.05); (3) the ultrastructural injuries of nPf neurons, which were in the nucleus, organelles and neuropil, were marked in the morphine dependent and withdrawal groups. Our study indicated that nPf played an important role in the development of morphine dependence and withdrawal. The results suggest that nPf may become a therapeutic target for treating morphine withdrawal syndrome.

BM stromal cells ameliorate experimental autoimmune myasthenia gravis by altering the balance of Th cells through the secretion of IDO.

In addition to their capacity to differentiate, BM stromal cells (BMSC) have immunosuppressive qualities that make them strong candidates for use in cell therapy against human autoimmune diseases. We studied the immunoregulatory activities of BMSC on experimental autoimmune myasthenia gravis (EAMG) in vitro and in vivo. Intravenous administration of syngenic BMSC to EAMG-model rats on the day of their second immunization was effective in ameliorating the pathological features of the disease. In vitro, the proliferative ability of T cells or B cells from EAMG rats was inhibited when they were cocultured with BMSC at proper ratios. This inhibitory effect was at least partially dependent on the secretion of IDO. We also determined that the development of EAMG is accompanied by an imbalance among the Th1, Th2, Th17, and Treg cell subsets, and that this can be corrected by the administration of BMSC, which leads to an increase of Th2 (IL-4) and Treg (Foxp3) cells, and a reduction of Th1 (IFN-gamma) and Th17 (IL-17) cells, through an IDO-dependent mechanism. These results provide further insights into the pathogenesis of MG, EAMG, and other immune-mediated diseases, and support a potential role for BMSC in their treatment.

Administration of bone marrow stromal cells ameliorates experimental autoimmune myasthenia gravis by altering the balance of Th1/Th2/Th17/Treg cell subsets through the secretion of TGF-beta.

Bone marrow stromal cells (BMSCs) are strong candidates for cell therapy against human autoimmune diseases. Intravenous administration of syngenic BMSCs to EAMG-model rats effectively ameliorated the disease, partially through a TGF-beta-dependent mechanism. The proliferative ability of T or B cells from EAMG rats was inhibited by BMSCs at proper cocultured ratios. And the imbalance of Th1, Th2, Th17 and Treg cell subsets accompanied with the development of EAMG was corrected by the administration of BMSCs. These results provide further insights into the pathogenesis of MG, EAMG, and other immune-mediated diseases, and support a potential role for BMSCs in their treatment.

RAGE expression is up-regulated in human cerebral ischemia and pMCAO rats.

To determine whether the receptor for advanced glycation endproducts (RAGE) contributes to cerebral ischemia, we evaluated RAGE expression in human cerebral ischemia and a model of permanent middle cerebral artery occlusion (pMCAO) in rats. Biopsy specimens were obtained from 12 patients with unilateral cerebral infarction. For the pMCAO model, the middle cerebral artery (MCA) of Sprague-Dawley (SD) rats was permanently occluded. Immunohistochemistry and Western blotting were used to measure RAGE expression in the ischemic hemisphere relative to the normal hemisphere. PC12 cells subjected to oxygen and glucose deprivation (OGD) were used to evaluate the role of RAGE in cell injury. As expected, cerebral ischemia patients expressed elevated levels of RAGE in the ischemic hemisphere. In 1 and 2 days pMCAO rats, levels of RAGE were higher in the ischemic hemisphere relative to the non-ischemic hemisphere, and expression was primarily located in the penumbra of the ischemic hemisphere. In PC12 cells, levels of RAGE increased after 7h of OGD culture. Notably, blockade of RAGE with a selective RAGE antibody in vitro reduced the cytotoxicity caused by OGD. The present data suggest that RAGE is up-regulated in human cerebral ischemia and pMCAO rats, suggesting a role for RAGE in brain ischemia.

Voriconazole into PLGA nanoparticles: improving agglomeration and antifungal efficacy.

This study is concerned with preparing PLGA nanoparticles loaded with voriconazole (PNLV), investigating the burst release and agglomeration of PNLV, and also evaluating antifungal efficacy of PNLV compared with voriconazole (VRC). The emulsion-solvent evaporation technique for nanoparticles and tests against fungi were completed. The amount of VRC in PNLV with sodium hexametaphosphate was 2.01+/-0.27%, and burst release of PNLV was reduced by about 33% using 20% ethanol solution (n=3). The mean D(50) of PNLV with or without this salt was 132.8 nm and 6.3 microm, respectively (n=5). In vitro; the fungal numbers treated with PNLV (3.5 mg/ml, equal amount calculated by VRC) and VRC (70 microg/ml) in tubes at the day 7 were 5.74 log(10) and 6.72 log(10), respectively (P<0.05). In vivo; the fungal burden treated with PNLV and VRC in tissue from mice kidneys at day 7 after administration was 0.64 log(10) and 2.61 log(10), respectively (5 mg/kg, P<0.001). The hematoxylin-eosin stain in mice kidney showed that the pathological lesions treated with PNLV were relieved in contrast with those with VRC. These results suggest that the emulsion-solvent evaporation process is feasible in preparing PNLV. Moreover, ethanol solution decreased burst release and Na-HMP inhibited agglomeration. PNLV could improve the VRC antifungal efficacy.