The effects of PRF and its three growth factors on the proliferation and adhesion of rat ADSCs / 实用口腔医学杂志

Objective:To study the effects of PRF and recombinant hPDGF-AB,TGF-β1 and VEGF on the proliferation and adhe-sion of rat adipose tissue-derived stem cells(ADSCs)in vitro.Methods:ADSCs were cultured with PRF membrane and various do-ses of PDGF-AB,TGF-β1 and VEGF,cell adhesion was examined by adhesion assay after 2 culture,cell proliferation was examined by CCK-8 kit after 1 -7 d culture.Results:Cell adhesion assay showed that the adhesive numbers of rat ADSCs in PRF group were significantly higher than those in the negative group(P 0.05).The adhesive numbers of the ADSCs treated by VEGF or TGF-β1 at different concentrations showed significant difference(P <0.05).CCK-8 kit assay showed that at different time points, the A values of ADSCs in PRF group were significantly higher than those of the negative control group(P <0.05).The A values of ADSCs in VEGF or PDGF-AB groups at different concentrations showed significant difference(P <0.05).The A values of rat AD-SCs in TGF-β1 group at different concentrations were lower than those in the negative control group(P <0.05).Conclusion:PRF as a combination of growth factors may stimulate the proliferation and adhesion of rat ADSCs in vitro.PDGF-AB and VEGF may stim-ulate the proliferation of rat ADSCs.TGF-β1 and VEGF may stimulate the adhesion of rat ADSCs in a dose-response manner to some degree.

Therapeutic effect of GDNF gene-modified mesencephalic neural stem cell transplantation in a rat model of Parkinson disease / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the therapeutic effect of transplantation of mesencephalic neural stem cells (mNSCs) genetically modified by glial cell line-derived neurotrophic factor (GDNF) gene in a rat model of Parkinson disease.</p><p><b>METHODS</b>mNSCs isolated from the lateral component of the midbrain of fetal rats at gestational age of 14 or 15 days were cultured for 5 days before genetic modification with GFP or GDNF gene. Rat models of Parkinson disease established by stereotactic injection of 6-hydroxy dopamine in the ventral area of the midbrain and the medial forebrain bundle were randomized into 3 groups to receive PBS injection, GFP gene-modified mNSCs transplantation, or GDNF gene-modified mNSCs transplantation into the right stratum. The behavioral changes of the rats were evaluated by observing rotations induced by intraperitoneal injection of apomorphine after the transplantation, and the survival, migration and differentiation of the transplanted cells were identified by immunohistochemistry.</p><p><b>RESULTS</b>Transplantation with GDNF gene-modified mNSCs significantly improved the behavioral abnormalities of the rat models as compared with PBS injection and GFP gene-modified mNSCs transplantation. At 56 days after the transplantation, a greater number of the transplanted cells survived in the rat brain and more differentiated dopaminergic neurons were detected in GDNF gene-modified mNSCs transplantation group than in GFP gene-modified mNSCs transplantation group.</p><p><b>CONCLUSION</b>GDNF gene-modified mNSCs transplantation can significantly improve dyskinesia in rat models of Parkinson disease, but the molecular mechanism needs further clarification.</p>

Ultrastructural changes of reconstructed mandibular condylar cartilage under continuous mandibular advancement / 中国组织工程研究

BACKGROUND:Previous animal experiments have demonstrated that mandibular advancement can cause the remodeling of temporomandibular joint tissue of young SD rats. This is mainly characterized by accelerated growth rate of the condyle tissue and secondary growth of mandible. But the ultrastructural remodeling of condylar chondrocytes remains poorly understood. OBJECTIVE:To observe the histological and ultrastructural variations of reconstructed condylar cartilage of young rats under the effect of continuous mandibular advancement. METHODS:SD rats aged 4 weeks were randomly divided into control and experimental groups. Rats in the experimental group were subjected to mandibular advancement for 24 hours and sacrificed at 3, 7, 14, 21 and 30 days of intervention. Condylar cartilage samples were harvested and their histological and ultrastructural changes were observed under optical microscope and transmission electron microscope. RESULTS AND CONCLUSION:After 14 days of intervention, the thickness of condylar cartilage in the experimental group increased first and then became thin in the period of observation. The cartilage thickness variations in the postmedian condylar were significant (P < 0.01). After 7 days of intervention, the ultrastructure of condylar chondrocytes was reconstructed, including intracelular karyopyknosis, rough endoplasmic reticulum compartment sweling, smaler even absent lipid droplets, less and irregular microfilaments around the nucleus, broadened and increased extracelular matrix and the emergence of large gaps. These results demonstrate that under continuous mandibular advancement, the rat condylar cartilage wil become thick or thin with the endurance time, and chondrocyte matrix synthesis ability wil be significantly enhanced.

The comparison of platelet-rich fibrin and platelet-rich plasma in releasing of growth factors and their effects on the proliferation and differentiation of adipose tissue-derived stem cells in vitro / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To compare the releasing of growth factors between platelet-rich fibrin (PRF) and platelet-rich plasma (PRP) as well as their effects on the proliferation and differentiation of adipose tissue-derived stem cells (ADSCs) in vitro.</p><p><b>METHODS</b>Blood was taken from central artery of rabbits, acquiring PRF was acquired through one time centrifuge and PRP through two times centrifuge. Five milliliters of fresh alpha-MEM was added to PRF and PRP and incubated at 37 degrees C. The time points to collect exudates was in day 1, 7, 14, 21, 28 and the mass concentrations of transforming growth factor-beta1 (TGF-beta1) and platelet derived growth factor-AB(PDGF-AB) were quantified in PRF and PRP. Then the exudates of PRF and PRP were used to culture ADSCs and evaluate the effects of PRF and PRP on proliferation and differentiation of ADSCs.</p><p><b>RESULTS</b>1) Growth factor release: In the PRF exudates at different time points, the mass concentration of TGF-beta1 was the highest at day 14 and the highest mass concentration of PDGF-AB at day 7, the mass concentration of both TGF-beta1 and PDGF-AB was the highest at the first day and then gradually declined. 2)The effect on proliferation and differentiation: PRF exudates of day 14 expressed the maximum proliferation and alkaline phosphatase (ALP) activity. PRF exudates of day 1 demonstrat the maximum proliferation and ALP activity.</p><p><b>CONCLUSION</b>Comparing to PRP, PRF releases growth factors gradually and expressed stronger and more durable effect on proliferation and differentiation of ADSCs in vitro.</p>

Influence of epidermal growth factor receptor monoclony antibody MAb225 on DNA repair of tongue carcinoma cell after radiation / 华西口腔医学杂志

<p><b>OBJECTIVE</b>The objective of this study is to investigate the effect of epidermal growth factor receptor (EGFR) monoclonal antibody MAb225 on repair of DNA double strand break (DNA-DSB) after radiation in tongue squamous cell carcinoma cell.</p><p><b>METHODS</b>The single cell gel electrophoresis (SCGE) was performed to estimate the repair of DNA-DSB induced by radiation in human tongue carcinoma cells Tca8113 treated with or without MAb225. Expression of Ku70 and Ku80 were detected by semiquantitative reverse transcription polymerase chain reaction and Western bolt.</p><p><b>RESULTS</b>Comet tail moment of MAb225 treated cell was significantly higher than untreated cell (P < 0.05). The expression of Ku70 and Ku80 were inhibited by MAb225.</p><p><b>CONCLUSION</b>MAb225 can inhibit repair of DNA-DSB induced by down-regulated expression of Ku70 and Ku80.</p>