Anti-COL3A1 polyclonal antibody

Intracellular Ca2+ signals are essential for stem cell function and play a significant role in the differentiation process. Dental pulp stem cells (DPSCs) are a potential source of stem cells; however, the mechanisms controlling cell differentiation remain largely unknown. Utilizing rat DPSCs, we examined the effect of adenosine triphosphate (ATP) on osteoblast differentiation and characterized its mechanism of action using real-time Ca2+ imaging analysis. Our results revealed that ATP enhanced osteogenesis as indicated by Ca2+ deposition in the extracellular matrix via Alizarin Red S staining. This was consistent with upregulation of osteoblast genes BMP2, Mmp13, Col3a1, Ctsk, Flt1, and Bgn. Stimulation of DPSCs with ATP (1-300 mu M) increased intracellular Ca2+ signals in a concentration-dependent manner, whereas histamine, acetylcholine, arginine vasopressin, carbachol, and stromal-cell-derived factor-1 alpha failed to do so. Depletion of intracellular Ca2+ stores in the endoplasmic reticulum by thapsigargin abolished the ATP responses which, nevertheless, remained detectable under extracellular Ca2+ free condition. Furthermore, the phospholipase C (PLC) inhibitor U73122 and the inositol triphosphate (IP3) receptor inhibitor 2-aminoethoxydiphenyl borate inhibited the Ca2+ signals. Our findings provide a better understanding of how ATP controls osteogenesis in DPSCs, which involves a Ca2+-dependent mechanism via the PLC-IP3 pathway. This knowledge could help improve osteogenic differentiation protocols for tissue regeneration of bone structures.

Resistin-like molecule alpha (RELM alpha) and YM-1 are secreted proteins implicated in murine models of alternatively activated macrophage (AA/M2) accumulation and Th2-skewed inflammation. Since the gp130 cytokine Oncostatin M (OSM) induces a Th2-like cytokine and AA/M2 skewed inflammation in mouse lung, we here investigated regulation of RELM alpha and YM-1. Transient pulmonary overexpression of OSM by Adenovirus vector (AdOSM) markedly induced RELM alpha and YM-1 protein expression in total lung. In situ hybridization showed that RELM alpha mRNA was highly induced in airway epithelial cells (AEC) and was co-expressed with CD68 mRNA in some but not all CD68+ cells in parenchyma. IL-6 overexpression (a comparator gp130 cytokine) induced RELM alpha, but at significantly lower levels. IL-6 (assessing IL-6(-/-)mice) was not required, nor was STAT6 (IL-4/13 canonical signalling) for AdOSM-induction of RELM alpha in AEC. AEC responded directly to OSM in vitro as assessed by pSTAT3 activation. RELM alpha-deficient mice showed similar inflammatory cell infiltration and cytokine responses to wt in response to AdOSM, but showed less accumulation of CD206+ AA/M2 macrophages, reduced induction of extracellular matrix gene mRNAs for COL1A1, COL3A1, MMP13, and TIMP1, and reduced parenchymal alpha smooth muscle actin. Thus, RELM alpha is regulated by OSM in AEC and contributes to extracellular matrix remodelling in mouse lung.