Co-culture of human bone marrow mesenchymal stem cells and macrophages attenuates lipopolysaccharide-induced inflammation in human corneal epithelial cells.

Dry eye syndrome (DES) is considered as an ocular surface inflammatory disease. Previous studies have shown inflammation plays an important role in the progression and onset of DES. Co-culture of human bone marrow mesenchymal stem cells (HBMSCs) and macrophages showed immunomodulatory effects via regulation of cytokine regulation. Thus, the aim of this study was to investigate the effect of the interaction of these cells on in vitro DES model. The conditioned media (CM) from macrophages, HBMSCs, and HBMSCs + macrophages were treated to human corneal epithelial cells, which showed significant reduction in IL-1α and IL-1ß expression levels in HBMSCs + macrophages group. Moreover, the IL-1 Receptor Antagonist (IL-1RA) was highly expressed in the CM from the HBMSCs + macrophages group. Wounded eyes of mice were treated with IL-1RA at 0-100 ng/mL for 16 h, the wound size was reduced. The results of this study might lead to the identification of new therapeutic targets for DES.

ß-cellulin promotes the proliferation of corneal epithelial stem cells through the phosphorylation of erk1/2.

The proliferation of corneal epithelial stem cells (CESCs) is a very important process in the recovery of corneal wounds. Recent studies have shown that ß-cellulin (BC) is effective in the repair of other tissues. However, its mechanism of action in corneal wound healing is not yet clear. The purpose of this study was to investigate how BC accelerates wound healing of the cornea. Here, we confirmed that the proliferation of CESCs was induced at a specific concentration (0.2, 2 and 20 ng/mL) by treatment with BC. Markers associated with proliferation activity (ΔNp63, bmi-1, abcg2) were also upregulated. In vivo experiments showed that the corneal wound healing rate was increased in mice. We found that BC stimulates the phosphorylation of the erk1/2 signaling pathway, which is triggered during the recovery of mouse corneal wounds. However, the inhibition of erk1/2 phosphorylation delayed the recovery of mouse corneal wounds in an organ culture assay. According to these results, BC may be a potential treatment factor for corneal wound healing.

Extremely low-frequency electromagnetic field promotes astrocytic differentiation of human bone marrow mesenchymal stem cells by modulating SIRT1 expression.

It has been shown that extremely low-frequency electromagnetic fields (ELFMF) affect regulation of cell fate and differentiation. Thus, the aim of this study was to investigate the role of ELFMFs in the enhancement of astrocytic differentiation. ELFMF exposure reduced the rate of proliferation and enhanced astrocytic differentiation. The ELFMF-treated cells showed increased levels of the astrocyte marker (GFAP), while those of the early neuronal marker (Nestin) and stemness marker (OCT3/4) were downregulated. The reactive oxygen species (ROS) level was observed to be significantly elevated after ELFMF exposure, which strengthens the modulatory role of SIRT1 and SIRT1 downstream molecules (TLE1, HES1, and MASH1) during astrocytic differentiation. After nicotinamide (5 mM) mediated inhibition of SIRT1, levels of TLE1, HES1, and MASH1 were examined; TLE1 was significantly upregulated and MASH1 was downregulated. These results suggest that ELFMFs induce astrocytic differentiation through activation of SIRT1 and SIRT1 downstream molecules.

Neuregulin-1 accelerates corneal epithelial wound healing.

Corneal epithelial cells (CECs) play an important role in the function of the cornea, and are maintained by corneal epithelial stem cells (CESCs). Recent studies have shown that neuronal growth factors affect the proliferation and migration of CESCs. Neuregulin-1 (NR-1) is a neuronal growth factor that is expressed in the early stages of brain development. The aim of this study was to determine whether NR-1 activates corneal wound healing. We observed that NR-1 activated both proliferation and migration of CECs. In addition, the colony-forming efficacy of CESCs was enhanced. In mice, NR-1 treatment improved corneal wound healing. Furthermore, the expression of markers of corneal epithelium maintenance (ΔNp63) and CESC proliferation (Bmi-1 and Abcg2) was increased. These effects were mediated by intracellular signalling pathways (Stat3, Erk1/2 and p38). Taken together, our results suggest that NR-1 accelerates the recovery of corneal wounds, and may represent a novel treatment for corneal damage.

Perpendicular Magnetic Anisotropy in FePt Patterned Media Employing a CrV Seed Layer.

A thin FePt film was deposited onto a CrV seed layer at 400°C and showed a high coercivity (~3,400 Oe) and high magnetization (900-1,000 emu/cm(3)) characteristic of L 10 phase. However, the magnetic properties of patterned media fabricated from the film stack were degraded due to the Ar-ion bombardment. We employed a deposition-last process, in which FePt film deposited at room temperature underwent lift-off and post-annealing processes, to avoid the exposure of FePt to Ar plasma. A patterned medium with 100-nm nano-columns showed an out-of-plane coercivity fivefold larger than its in-plane counterpart and a remanent magnetization comparable to saturation magnetization in the out-of-plane direction, indicating a high perpendicular anisotropy. These results demonstrate the high perpendicular anisotropy in FePt patterned media using a Cr-based compound seed layer for the first time and suggest that ultra-high-density magnetic recording media can be achieved using this optimized top-down approach.