Abstract-Widely used tetracycline antibiotics affect many cellular functions relevant to human vascular disease including cell proliferation, migration, and matrix remodeling. We examined whether minocycline inhibited human aortic smooth muscle cell (HASMC) migration induced by vascular endothelial growth factor (VEGF). After the establishment of an optimal dose, minocycline treated HASMC were exposed to VEGF. HASMC migration, matrix metalloproteinase (MMP)-2 and MMP-9 activities, mitogen-activated protein kinase (MAPK), and phosphatidylinositol 3-kinase (PI3K) phosphorylation were determined by smooth muscle cell (SMC) invasion assay, real-time polymerase chain reaction, zymograms, and Western blot analysis, respectively. We demonstrated that VEGF and platelet-derived growth factor (PDGF)-induced SMC migration in a dose-dependent manner. MMP-9, but not MMP-2, mRNA was increased during VEGF stimulation. MMP-9 activity was increased from 1.5-to 2.5-fold in a dose-dependent manner (PϽ0.05). Both ERK1/2 and PI3K/AKt pathways were activated during VEGF-induced HASMCs migration. We then demonstrated that minocycline can inhibit VEGF-induced HASMC migration (PϽ0.05). The effects may be through the inhibition of MMP-9 mRNA transcription, protein activities and downregulation of ERK1/2 and PI3K/Akt pathway phosphorylation. Our results indicated that minocycline exerts multiple effects on VEGF-induced SMC migration, including inhibition of MMP-9 mRNA transcription and protein activities and downregulating ERK1/2 and PI3K signal pathways, suggesting minocycline may be a potentially therapeutic approach to inhibit disease process induced angiogenesis.

Baculovirus nucleocapsids egress from the nucleus primarily via budding at the nuclear membrane. The nuclear lamina underlying the nuclear membrane represents a substantial barrier to nuclear egress. Whether the nuclear lamina undergoes disruption during baculovirus infection remains unknown. In this report, we generated a clonal cell line, Sf9-L, that stably expresses GFP-tagged Drosophila lamin B. GFP autofluorescence colocalized with immunofluorescent anti-lamin B at the nuclear rim of Sf9-L cells, indicating GFP-lamin B was incorporated into the nuclear lamina. Meanwhile, virus was able to replicate normally in Sf9-L cells. Next, we investigated alterations to the nuclear lamina during baculovirus infection in Sf9-L cells. A portion of GFP-lamin B localized diffusely at the nuclear rim, and some GFP-lamin B was redistributed within the nucleus during the late phase of infection, suggesting the nuclear lamina was partially disrupted. Immunoelectron microscopy revealed associations between GFP-lamin B and the edges of the electron-dense stromal mattes of the virogenic stroma, intranuclear microvesicles, and ODV envelopes and nucleocapsids within the nucleus, indicating the release of some GFP-lamin B from the nuclear lamina. Additionally, GFP-lamin B phosphorylation increased upon infection. Based on these data, baculovirus infection induced lamin B phosphorylation and disruption of the nuclear lamina.

The dispersity of graphene (GE) in the matrix has an important influence on the thermal, mechanical, and electrical properties of its derived composites. In this paper, surface modification with a silane coupling agent and a double injection method were used to improve the dispersity of GE in epoxy resin (EP). The thermal, mechanical, and electrical properties of modified graphene/epoxy resin composites (modified GE/EP) were investigated by the thermogravimetric analysis, a four-probe method, and the tensile and bending strength. The results reveal that these properties of the composites can be improved significantly by using the modified GE as the filler. The surface of the modified GE/EP composite was smooth when the curing temperature was 75 °C. The weight loss of the modified GE/EP composite was lower than that of pure EP. The tensile and bending strength of modified GE/EP-0.07 (0.07 wt % modified GE) reached 74.65 and 106.21 MPa, respectively. In addition, the resistivity of modified GE/EP-0.1 (0.1 wt % modified GE) decreased to 52 Ω·cm, which was lower than that of CB/EP-1 (1 wt % carbon black, 95 Ω·cm) and Ag/EP-50 (50 wt % Ag particles, 102 Ω·cm). It is worth noting that the percolation threshold of the modified GE/EP composites was 0.025 vol % modified GE. These results show that the modified GE/EP composites have a potential application in conductive ink when the modified GE is used as the conductive filler.

Previous studies suggest that mesenchymal stem cells may represent a promising cellular therapy for acute lung injury (ALI); however, the underlying relevant molecular mechanisms remain unclear. Adipose-derived mesenchymal stem cells (ADSCs) were isolated and characterized by alizarin red staining, oil red staining, and flow cytometry. Lung injury and inflammatory cell infiltration were determined using the Evans blue method, wet/dry weight ratio, and H&E staining. An ELISA was used to detect the concentrations of IFN-γ, IL-2, and TNF-α. Autophagy was detected with an mRFP-GFP-LC3 dual-fluorescence autophagy indicator system, Western blotting, and electron microscopy. We first demonstrated that ADSCs did alleviate the inflammatory responses and tissue damage in lipopolysaccharide (LPS)-induced ALI. Next, we further demonstrated in vivo that autophagy plays a key role in the maintenance of ADSC therapeutic efficacy. In vitro experiments demonstrated that ADSCs co-cultured with alveolar epithelial cells depend on autophagy for significant anti-inflammatory functions. Moreover, the mammalian target of rapamycin (mTOR) is a key regulator of autophagy. Taken together, our findings demonstrate that the effect of ADSC on ALI, especially on alveolar epithelial cells, is dependent on mTOR-mediated autophagy maintenance. The significance of our study for ALI therapy is discussed with respect to a more complete understanding of the therapeutic strategy paradigm.

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