Browsing by Subject "MMPs"

Now showing 1 - 3 of 3
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    Immunolocalization of MMP 2, 9 and 13 in prednisolone induced osteoporosis in mice
    (Universidad de Murcia. Departamento de Biología Celular e Histología, 2016) Sun, Bao; Sun, Jing; Han, Xiuchun; Liu, Hongrui; Li, Juan; Du, Juan; Feng, Wei; Liu, Bo; Cui, Jian; Guo, Jie; Amizuka, Norio; Li, Minqi
    Long-term use of glucocorticoids (GC) causes rapid bone loss and increases the risk of osteoporotic fractures. Matrix metalloproteinase (MMPs), the most prominent kind of proteases implicated in the proteolytic degradation of the extracellular matrix (ECM), have been reported to be involved in pathological process of GC induced osteoporosis. However, the underlining mechanisms are still unclear. The aim of this study was to investigate the spatial expression and the potential function of MMP 2, 9 and 13 in osteoporosis induced by prednisolone in the tibiae of mice. In this experiment, mice were given prednisolone (15 mg/kg body weight) in PBS intragastrically every other day, or only PBS as control. Two weeks later, mice were fixed with transcardial perfusion of 4% paraformaldehyde in 0.1 M phosphate buffer (pH 7.4), and tibiae were extracted for histochemical analysis. Compared with control group, the number of TRAP-positive osteoclasts and the immunoreactivity of MMP 2, 9 and 13 were significantly increased in the trabecular bone of mice administered with prednisolone, leading to the decrease of trabecular bone volume. On the other hand, lighter eosin staining areas containing numerous empty lacunae of osteocytes and crevices were seen in the narrowing cortical bone. Furthermore, intense immunoreaction of MMP 2 and MMP 13 were found in the enlarged lacunae and the crevices, respectively. Taken together, we concluded that prednisolone administration induced the increase of MMP 2, 9 and 13 expressions, while MMP 2 and MMP 13 played essential roles in the osteocytic osteolysis and the early impaired areas in the cortical bone. Therefore, MMPs might be new potential therapeutic targets for prevention and treatment of glucocorticoid induced osteoporosis, especially osteocytic osteolysis.
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    Morphological changes in mouse ovary due to hormonal hypersecretion and matrix metalloproteinase-2 activity
    (Universidad de Murcia, Departamento de Biologia Celular e Histiologia, 2021) Kim, Sang-Hwan; Yoon, Jong-Taek
    We analyzed whether aberrant gonadotropin secretion affects the morphological remodeling of murine ovarian tissues facilitated by activated matrix metalloproteinase (MMP) enzymes. Six mice were intraperitoneally injected with 5 IU of pregnant mare serum gonadotropin (PMSG) or human chorionic gonadotropin (HCG) every two days after estrus synchronization. Morphology and expression of various MMPs were assessed following the successful induction of hormonal secretion in these tissues. HCG treatment, but not PMSG treatment, resulted in the expanded production of granulose second follicular cells. In addition, the number of developing follicular cells in the HCG group increased compared with that in the PMSG group. Ovarian diameters were also very small in the PMSG group. Immunohistochemistry revealed decreased MMP-2 protein activity in the HCG group and increased MMP-2 activity in the PMSG group. Activity was particularly high in theca and granulose cells of the PMSG group, but only partial activity was observed in the theca cells of the HCG group. Vascular endothelial growth factor activity was increased in both the external and internal theca cell walls in the PMSG group while the HCG group showed high overall expression of this protein in the internal theca cells. These data indicate that follicular cell activity and remodeling of the ovaries differ based on the type of secretory hormone signals they receive. Inappropriate gonadotropin secretion may induce functional changes in the ovaries, and follicular remodeling may be facilitated by the activity of various MMPs.
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    Porcine endometrial 3D co-culture: Morphological changes in 3D endometrium tissues according to hormonal changes
    (Universidad de Murcia, Departamento de Biologia Celular e Histiologia, 2021) Kim, Sang-Hwan; Park, Yong-Su; Shin, Da-Hye; Moon, Jeong-Chan; Oh, Min-Gee; Yoon, Jong-Taek
    Cells cultured as monolayers proliferate well, but do not sustain their differentiation characteristics. Previous studies have investigated the interactions between cells and growth factors or cytokines by establishing either in vivo or in vitro three-dimensional (3D) cultures. Using porcine uterine epithelial cells and endometrial cells, the current study was designed to develop a 3D uterine culture system and investigate the response to hormone treatment. Formation of the 3D uterine model was similar to that of uterus from the group supplemented with calcium and magnesium, and the addition of these ions altered the spectrum of basement membrane degrading enzyme expression and activity. In particular, the epithelial cell junctions in the 3D model most closely resembled those of an actual uterus when the medium was supplemented with calcium and magnesium; the intercellular basement membrane structure was also tall under these conditions. The study confirmed that Casp-3 expression was lowest in the P4 (progesterone) treatment group, and this hormone was the most potent stimulus for formation of the endometrial cell layer. Therefore, the addition of calcium and magnesium plays an important role in the formation of a 3D uterine model, and the addition of P4 hormone mimics uterine thickening by stimulating growth of the epithelial cell layer.