Memantine inhibits 6-OHDA-induced apoptosis PC12 cells via the Nurr77 and caspase pathway

Objective: To investigate the effect of memantine on Parkinson's disease cell models. Methods: Parkinson's disease cell models were established using PC12 cells incubated with 6-hydroxydopamine (6-OHDA). Flow cytometry and microscopy were used to investigate the apoptotic process and the percentage of different apoptotic stages. PC12 cells were infected with lentiviral vectors to knockdown Nur77. Western blotting was used to detect the expression of Nur77 and caspase -3, -8, -9, -12 in PC12 cells withdifferent concentrations of 6-OHDA or 6-OHDA+memantine. Results: 6-OHDA led to apoptosis PC12 cells, and increased the expression of Nur77 and caspases. Memantine significantly inhibited 6-OHDA-induced apoptosis of PC12 cells. Meanwhile, memantine could mitigate apoptosis of PC12 cells by regulating the Nur77 and caspase pathway. Conclusions: Memantine has a protective effect on the PC12 cell model via regulating the Nur77 and caspases pathway.

Comparative studies of hemorheological parameters in Tibet mini-pigs, Beagle dogs and human / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the relationship of hemorheological parameters between Tibet mini-pigs, Beagle dogs and human.</p><p><b>METHODS</b>Blood samples were collected from adult Tibet mini-pigs, Beagle dogs and human to detect such hemorheological parameters as the whole blood viscosity (WBV) (high, middle, and low shear rate), PV, HCT, ESR and Fi.</p><p><b>RESULTS</b>The male Tibet mini-pigs had significantly lower WBV (150, 30, 5, and 1 s(-1)) and Fi than the female mini-pigs (P<0.05, 0.01, 0.05, 0.01, and 0.01, respectively). The WBV of male Beagle dogs (150 and 1 s(-1)) was significantly lower that in than female dogs (P<0.05). The WBV of male human subjects (1 s(-1)) and HCT were significantly higher, but ESR significantly lower than those in female human subjects P<0.05, 0.01 and 0.01, respectively). WBV (1 s(-1)), PV, and ESR in Beagle dogs were significantly lower, but HCT and Fi significantly higher than those in Tibet mini-pig and human subjects (P<0.05, 0.01, 0.05, and 0.01, respectively). All the hemorheological parameters were similar between Tibet mini-pigs and human (P<0.05).</p><p><b>CONCLUSION</b>The hemorheological parameters of Tibet mini-pigs are closer to those of human than those of Beagle dogs.</p>

Mitochondrial DNA D-loop variation types in Tibet mini-pigs in association with the blood parameters / 南方医科大学学报

<p><b>OBJECTIVE</b>To analyze the mitochondrial DNA (mtDNA) D-loop region sequence variation in Tibet Mini-Pigs in relation to the blood parameters and provide the molecular genetic basis for developing new species of laboratory animals.</p><p><b>METHODS</b>The genomic DNA was extracted from the whole blood samples of 59 Tibet mini-pigs to amplifying the mtDNA D-loop for sequence analysis. Nine physiological and nine biochemical blood parameters of Tibet mini-pigs were measured .</p><p><b>RESULTS</b>Based on the variation of the tandem repeat motif, the mtDNA D-loop region of Tibet mini-pigs was classified into two types, namely type A and B with the percentage of 57.6% and 42.4%, respectively, roughly matching the 3 transform sites (305, 500, 691) at the 5' end. In the 18 blood parameters, only red blood cell count showed significant differences between types A and (P<0.01).</p><p><b>CONCLUSION</b>Based on the sequence variation of the mtDNA D-loop region, Tibet mini-pigs can be divided into two types that show a significant difference in red blood cell count.</p>

Effect of juglone on the ultrastructure of human liver cancer BEL-7402 cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the effect of juglone on the ultrastructure of human liver cancer BEL-7402 cells.</p><p><b>METHODS</b>BEL-7402 cells were incubated in the presence of 12.5 micromol/L juglone for 24 h, and fixed in 2.5% glutaraldehyde for HE staining and Coomassie brilliant blue staining and scanning electron microscopy.</p><p><b>RESULTS</b>Incubation with juglone resulted in obvious changes in the cell morphology and cytoskeletal alterations of the cells. Scanning electron microscopy revealed reduced volume of the cell bodies, dissociation of the cells, curling and malformation of the microvilli on the cell surface with rupture of the intercellular junction and enlargement of the intercellular space. The formation of apoptotic bodies was observed. Transmission electron microscopy showed expansion of the endoplasmic reticula, mitochondrial cristea disintegration, nucleolar fragmentation and formation of the apoptotic bodies after the exposure to juglone for 24 h.</p><p><b>CONCLUSION</b>Juglone can cause ultrastructural changes of human liver cancer BEL-7402 cells and induce their apoptosis.</p>

Mechanism of rat sciatic nerve regeneration induced by human hair keratin / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the effect of human hair keratin (HHK) in peripheral nerve repair and explore the mechanism of sciatic nerve regeneration.</p><p><b>METHODS</b>Rat models of sciatic nerve damage was established by creating a 10-mm gap in the sciatic nerve, which was bridged with a HHK implant. Histological examinations of the nerve tissues were performed at different time points after the surgery.</p><p><b>RESULTS</b>During the period from 2 days to 2 weeks following HHK implantation, Schwann cells were found to undergo dedifferentiation and proliferate along the HHK implant. Three weeks after HHK implantation, numerous macrophages and megakaryocytes occurred around the HHK, and a large quantity of regenerated Schwann cells aligned in orderly fashion was seen between the fine filaments of partially degraded HHK, where axons and capillaries were also observed. Six weeks later, massive nerve fibers and capillaries developed around the HHK, and at 9 weeks, the HHK implant was substantially degraded and numerous regenerated nerve fibers occurred characterized by obvious epineurium and perineurium. Till 12 weeks after HHK implantation, HHK was almost completely degraded and replaced by the newly regenerated nerve fibers that had grown across the nerve defect.</p><p><b>CONCLUSIONS</b>HHK is an ideal material for nerve injury repair. Apocytosis plays a key role in the differentiation process of highly differentiated Schwann cells into immature Schwann cells following nerve injury. As a protective mechanism, the axons undergo enclosure and dissociation following injuries, and the intact axons give rise to growth cones that extend fibers of growing buds to competitively bind the one or more Schwann cells, but only one such but finally develops into a complete axon. The nerve fiber barrier membrane is derived from the capillary menchymal stem cells and the outmost vascular barrier membrane. The regeneration of the Schwann cells, axons and the nerve membrane is the result of self-organization through a well synchronized and coordinated mechanism.</p>

Generation of transgenic mice by intratesticular injection and electroporation in vivo / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the feasibility of establishing transgenic mice by means of seminiferous tubule microinjection and electroporation (EP) in vivo.</p><p><b>METHODS</b>Specific pathogen-free (SPF) male Kunming mice divided into 4 groups were subjected to microinjection of two different transfection solutions labeled with enhance green fluorescent protein (EGFP) into the seminiferous tubule of the testis, and in one of the two groups receiving the identical transfection solutions, EP in vivo was performed. After two weeks, the male mice of each group were mated with SPF female Kunming mice with superovulation treatment, and PCR coupled with Southern blotting was performed for the offspring mice.</p><p><b>RESULTS</b>The results of PCR suggested significant difference in the efficiency of exogenous gene integration between the 4 groups (P<0.01), among which group A achieved the greatest efficiency (45%). Southern blotting did not identify significant difference between the 4 groups (P>0.05), but still suggested the highest efficiency in group A (25%).</p><p><b>CONCLUSION</b>Seminiferous tubule microinjection in conjunction with subsequent EP in vivo can remarkably enhance the integration efficiency of exogenous genes into the host genome, but this new method needs to be further tested for its potential utility in transgenic animal generation.</p>

Methanol extract of Celastrus orbiculatu suppresses synovial hyperplasia and cartilage erosion and degradation in rheumatoid arthritis / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effects of methanol extract of Celastrus orbiculatu (MECO) on synovial hyperplasia and cartilage erosion and degradation in rheumatoid arthritis (RA), and explore the possible mechanisms to provide clues for new drug development for RA treatment.</p><p><b>METHODS</b>The articular synovium from patients with RA and normal articular cartilage were co-implanted into the back of severe combined immunodeficient (SCID)mice to establish the chimeric model SCID- HuRAg. Four weeks later, the mice were given MECO intragastrically at 30 mg/day, leflunomide at 500 microg/day or distilled water, respectively, for 4 consecutive weeks. After completion of the treatments, the histological scores of the grafts for synovial hyperplasia, cartilage invasion by synoviocyte and cartilage degradation around the chondrocytes were evaluated, and serum level of tumor necrosis factor-alpha (TNF-alpha) was measured with radioimmunoassay. The expression of TNF-alpha mRNA and the cell apoptosis in the synovium were detected with in situ hybridization (ISH) and TUNEL, respectively, and the results were analyzed with the image analysis system.</p><p><b>RESULTS</b>The grafts survived in the mice till the end of experiment. MECO and leflunomide, in comparison with distilled water, significantly lowered the scores for synovial hyperlasia (2.00+/-0.76 and 2.25+/-0.89 vs 3.63+/-0.52), cartilage erosion (1.69+/-0.80 and 2.00+/-1.36 vs 3.75+/-0.53), cartilage degradation (1.88+/-0.83 and 2.13+/-0.83 vs 3.63+/-0.74) and serum TNF-alpha level (0.84+/-0.09 and 0.83+/-0.12 vs 0.99+/-0.11 ng/ml). Cell apoptosis of the synovium increased significantly with MECO and leflunomide treatments, but the expression of TNF-alpha mRNA in the synovium decreased significantly in MECO group.</p><p><b>CONCLUSION</b>MECO can effectively suppress synovial hyperplasia and cartilage erosion and degradation SCID-HuRAg mice by reducing TNF-alpha production in the synovium and promoting synovial apoptosis. MECO can be comparable with leflunomide in their effect, but the former is more effective in suppressing TNF-alpha expression in the synovium.</p>