Co-cultures of human coronary smooth muscle cells and dimethyl sulfoxide-differentiated HL60 cells upregulate ProMMP9 activity and promote mobility-modulation by reactive oxygen species

Effects of IL-1β on MMP-9 Expression in Cementoblast-Derived Cell Line and MMP-Mediated Degradation of Type I Collagen

It has been reported that matrix metalloproteinases (MMPs) are induced by many cytokines, and they are involved in various inflammatory processes, including periodontitis. However, the effects of interleukin-1β (IL-1β) on MMP-9 expression in cementoblasts, the cells responsible for cementum production, remain largely unknown. In this study, we used qPCR and gelatin zymogram analysis to show that IL-1β upregulated MMP-9 expression in cementoblast-derived cell line. Several signaling pathways, such as ERK1/2, JNK, p38, and AP-1 (c-Fos and ATF-2), were activated in response to IL-1β stimulation. Furthermore, enhancement of AP-1 activity by IL-1β was further confirmed by the AP-1 reporter assay and the electrophoretic mobility shift assay (EMSA). Pretreatment with specific inhibitors of ERK1/2 (U0126), JNK (SP600125), and AP-1 (tanshinone IIA) attenuated IL-1β-induced MMP-9 expression. In addition, inhibitors of ERK1/2 (U0126) and JNK (SP600125) attenuated IL-1β-enhanced AP-1 activity. This suggested that IL-1β stimulated AP-1 activation, at least partially, through ERK1/2 and JNK signaling pathways. Moreover, we found that IL-1β also upregulated the expression of MMP-13 and enhanced MMP-mediated degradation of type I collagen. Collectively, these results suggested that IL-1β induced MMP-9 expression by activation of AP-1 through the ERK1/2 and JNK signaling pathways in cementoblast-derived cell line and enhanced MMP-mediated collagen degradation possibly by MMP-13 and MMP-9.

Prophylactic efficacy of enteral miconazole administration for neonatal intestinal perforation and its potential mechanism

PURPOSE

Intestinal perforation (IP) is a fatal complication in extremely low birth weight infants (ELBWI). We started administrating enteral miconazole (MCZ) to ELBWI in 2002. Since then, the incidence of IP has significantly decreased. The aim of this study was to elucidate the prophylactic effect of MCZ for the treatment of neonatal IP, and to establish a new prophylactic concept for this disease.

METHODS

In in vivo experiments, the effects of MCZ were examined histopathologically using a mouse model of intestinal ischemia. In in vitro experiments, the cytoprotective effect of MCZ against hypoxia was evaluated using Caco-2 intestinal cells, and its anti-inflammatory potential using a co-culture model of Caco-2 and HL60 cells.

RESULTS

MCZ showed a tissue protective effect against intestinal ischemia. MCZ reduced high mobility group-box 1 (HMGB1) release in Caco-2 cells under hypoxic stress and attenuated the potential to activate co-cultured HL60 leukocytes with Caco-2 cells by suppressing interleukin-8 (IL-8).

CONCLUSION

MCZ may have preventive roles in the clinical management of IP in ELBWI by the suppression of IL-8 and HMGB-1.