ABSTRACT
Objective@#To investigate the effect of different mechanical loading on the expression of Notch-1, Notch-3, Jagged-1 and Delta-like-1 in growing rabbits' condylar cartilage.@*Methods@#Sixty-four ten-days-old rabbits were randomly divided into experimental and control groups. The rabbits in the experimental groups were fed on a powder diet, while the control groups were fed on a solid diet. The animals were sacrificed after 2, 4, 6 and 8 weeks. Notch-1, Notch-3, Jagged-1 and Delta-like-1 gene and protein expressions were examined by HE, immunohistochemistry, Western blotting and quantitative real-time PCR.@*Results@#At 2, 4, 6, 8 weeks, the anterior part of condylar cartilage in solid diet groups ([318.1±4.3], [342.4±2.6], [364.2±3.2], [380.7±6.0] mm, respectively) were thicker than those in powder diet groups ([275.4±2.6], [301.1±2.0], [322.3±3.3], [366.5±8.4] mm, respectively) (P<0.05). There was no significant difference between the two groups in the middle part (P>0.05). From 2 to 6 weeks, the posterior part of cartilage in solid diet groups ([444.1±1.5], [451.1±0.3], [476.4±5.7] mm, respectively) was thinner than those in power diet groups ([470.4±2.7], [494.3±2.9], [512.3±5.7] mm, respectively) (P<0.05). At 6 weeks, there were more mRNA expressions of Notch-3, Jagged-1 and Delta-like-1 in solid diet group than in power diet group (P<0.05). The Notch-1 protein could be found in all layers of condylar cartilage, especially in the surface of hypertrophic zone. The expressions of Notch-1, Notch-3, and Delta-like-1 protein were increased from 2 to 6 weeks, and decreased at 8 weeks. In solid diet groups, the protein expressions of Notch-1 (at 2, 4, 6, 8 weeks), Notch-3 (at 2, 4, 6 weeks), Jagged-1 (at 2, 4, 6 weeks) and Delta-like-1 (at 4, 6, 8 weeks) were greater than in power diet groups (P<0.05).@*Conclusions@#Low masticatory loading may delay or inhibit the development of condylar cartilage and its growing factors such as Notch-1, Notch-3, Jagged-1 and Delta-like-1. Appropriate masticatory loading plays an important role in normal development of the condyle.
ABSTRACT
Objective: To investigate the expression of peroxisome proliferator actived receptor ? (PPAR ?)and the inducement of apoptosis by PPAR ? ligand in renal cell carcinoma(RCC) derived cell lines.Methods:RT-PCR and Western blot analysis were performed to determined the expression of PPAR ? mRNA and protein in two RCC derived cell lines(786 O and A498) and two normal kidney(NK) derived cell lines(HK 2 and HMCC). Two RCC cell lines were treated with 50 ?mol/L troglitazoned for and evaluated for the effects of antidiabetic thiazolidinediones (TZDs) on the cells apoptosis by fluorescence microscopy and DNA ladder assay.The mutative expressions of Bcl 2 and Bax before and after TZDs treatment were also performed by western blot analysis. Results: The expression of PPAR ? was observed to be stronger in 786 O and A498 cells than in HK 2 and HMCC cells by RT-PCR and Western blot analysis. Treated with 50 ?mol/L troglitazone (for 48 h) it induced typical apoatosis in 786 O and A498 cells. After treatment, a decrease in Bcl 2 expression in RCC cells was observed by Western blot analysis,and the expression of Bax,however,was up regulated.Conclusion: The results reveal that troglitazone has the tumor suppressive effect on RCC cells. High affinity PPAR ? ligands (TZDs) may be the candidates for a novel approach to the treatment of this refractory neoplasm.
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the effect of Zilongjin (ZLJ) on human androgen-dependent type of prostate cancer cell line LNCaP.</p><p><b>METHODS</b>MTT assay, flow cytometry and fluorescence microscopy were used to observe the effect of ZLJ in anti-proliferation, cell cycle arresting and apoptosis induction. RT-PCR was used to examine the effect of ZLJ on expressions of prostate marker gene (PSA), androgen receptor (AR), apoptosis related genes (bcl-2 and bax), and Western blot assay was used to detect the effect on protein expression of bcl-2 and bax.</p><p><b>RESULTS</b>ZLJ could cause apparent inhibition on proliferation, induce G0/G1 phase arresting and apoptosis in time- and dose-dependent manner on LNCaP cells. The concentration for inhibiting cell growth by 50% (IC50) in 72 hrs was 0.79 mg/ml. ZLJ could down-regulate the expression of PSA, AR, bcl-2 genes and lower bcl-2 protein expression, but showed ineffective on bax protein expression.</p><p><b>CONCLUSION</b>ZLJ displays its anti-tumor effects by way of inhibiting the cell proliferation, arresting the G0/G1 phase, inducing apoptosis, down-regulating PSA, AR, bcl-2 gene expression and lowering bcl-2 protein expressions.</p>