Effect of bone marrow mesenchymal stem cells on healing of temporomandibular joints in rats with induced rheumatoid arthritis.

The healing capacity of bone marrow mesenchymal stem cells (BMMSCs) has been evaluated in various studies. This study aimed to evaluate the effect of BMMSCs on the healing of temporomandibular joints (TMJs) with induced rheumatoid arthritis. Fifty healthy male Sprague Dawley rats were divided into three groups: group I (n = 10), negative control; group II (n = 20), positive control (induction of arthritis by adjuvant followed by intravenous injection of 0.1 ml of PBS); and group III (n = 20), intervention (as for group II but injected intravenously with 1 × 106  cells ml-1 of BMMSCs suspended in PBS). Half of the rats in each group were euthanized 3 wk after the start of the experiment and the other half was euthanized after 5 wk. Group I revealed normal TMJ features. Group II showed thickening of disc, thinning of cartilage, disordered bone trabeculae, and decreased in mean % area staining positive of collagen fibers at 3 wk, while at 5 wk these effects were more aggravated. Group III showed nearly normal thickness of disc and condylar cartilage, nearly normal arrangement of bone trabeculae and regenerated collagen fibers at 3 wk, while after 5 wk the TMJ features were almost normal. Two-way anova revealed statistically significant differences between groups. Thus, treatment of induced rheumatoid arthritis with BMMSCs shows promising results that need to be further investigated in humans.

In vivo association of immunophenotyped macrophages expressing CD163 with PDGF-B in gingival overgrowth-induced by three different categories of medications.

AIMS: This study was carried out to identify and outline the degree of relationship between immunophenotyped macrophages expressing CD163 and PDGF-B in cyclosporine-A, phenytoin, and nifedipine-induced gingival overgrowth. METHODS: Eighty adult male albino rats were selected and divided into four equal groups. Group I received no treatment. Rats of groups II, III, and IV were administered cyclosporine-A, phenytoin, and nifedipine, respectively. Routine tissue processing was carried out for staining with CD163 and PDGF-B. The results of this study were analyzed statistically. RESULTS: Group I exhibited score 0 gingival overgrowth while group II yielded score 3 with blunt and bulbous gingival crests. Rats of group III showed score 2 with knife edge and group IV revealed less pronounced gingival overgrowth and mostly the gingival crest was knife edge. Group II had the highest mean value for CD163 while group I showed the lowest value. In addition, group II had the highest mean value for PDGF-B while group I showed the lowest value. Statistically, there was an overall significant difference between the studied groups as well as between each two groups. CONCLUSION: Strong association exists between immunophenotyped macrophages expressing CD163 and PDGF-B in GO induced by these medications. In addition, CD163 and PDGF-B upregulated in cyclosporine-A-induced GO compared to phenytoin and nifedipine medications.

Biological roles of KGF, CTGF and TGF-ß in cyclosporine-A- and phenytoin- induced gingival overgrowth: A comparative experimental animal study.

OBJECTIVE: To identify the possible biological roles of keratinocyte growth factor (KGF), connective tissue growth factor (CTGF) and transforming growth factor-ß (TGF-ß) in cyclosporine-A (CsA) and phenytoin (PNT)-induced gingival overgrowth (GO) and to correlate them with each other. METHODS: Sixty adult male albino rats were selected and divided into 3 equal groups. Group I rats received no treatment. Group II rats were administrated CsA for 7 weeks. Group III were administrated PNT for the same period. Rats were euthanized at the end of the experiment and routine tissue processing was carried out. The obtained specimens were stained with H&E, KGF, CTGF and TGF-ß antibodies. RESULTS: One-way MANOVA test for KGF, CTGF and TGF-ß revealed an overall significant difference between the different groups (P<0.001). LSD post hoc test for multiple comparisons revealed a significant difference between each two groups. Two-tailed Pearson correlation for group II revealed non-significant weak positive correlations between KGF & CTGF and between CTGF & TGF-ß. Non-significant weak negative correlation was found between KGF & TGF-ß. Meanwhile, group III revealed non-significant weak positive correlation between KGF & TGF-ß and between CTGF & TGF-ß. Significant moderate positive correlation was found between KGF & CTGF. CONCLUSION: The findings of the present study indicated that KGF, CTGF and TGF-ß have biological roles in progression of CsA- and PNT- induced GO. KGF plays a greater role in CsA- induced GO than in PNT- induced GO. Meanwhile, CTGF and TGF-ß play a role in PNT- induced GO greater than in CsA- induced GO.