Recent
studies show that biomaterials are capable of regulating
immune responses to induce a favorable osteogenic microenvironment
and promote osteogenesis and angiogenesis. In this study, we investigated
the effects of zinc silicate/nanohydroxyapatite/collagen (ZS/HA/Col)
scaffolds on bone regeneration and angiogenesis and explored the related
mechanism. We demonstrate that 10ZS/HA/Col scaffolds significantly
enhanced bone regeneration and angiogenesis in vivo compared with HA/Col scaffolds. ZS/HA/Col scaffolds increased tartrate-resistant
acid phosphatase (TRAP)-positive cells, nestin-positive bone marrow
stromal cells (BMSCs) and CD31-positive neovessels, and expression
of osteogenesis (Bmp-2 and Osterix) and angiogenesis-related (Vegf-α and Cd31) genes increased in nascent bone. ZS/HA/Col scaffolds
with 10 wt % ZS activated the p38 signaling pathway in monocytes.
The monocytes subsequently differentiated into TRAP+ cells
and expressed higher levels of the cytokines SDF-1, TGF-β1,
VEGF-α, and PDGF-BB, which recruited BMSCs and endothelial cells
(ECs) to the defect areas. Blocking the p38 pathway in monocytes reduced
TRAP+ differentiation and cytokine secretion and resulted
in a decrease in BMSC and EC homing and angiogenesis. Overall, these
findings demonstrate that 10ZS/HA/Col scaffolds modulate monocytes
and, thereby, create a favorable osteogenic microenvironment that
promotes BMSC migration and differentiation and vessel formation by
activating the p38 signaling pathway.
Human malignant melanoma is a common primary malignant cutaneous tumour derived from transformed epidermal melanocytes. Patients with melanoma have a high rate of mortality due to resistance to chemotherapeutic drugs, a major obstacle to a successful treatment. Several reports have suggested that CD146 plays an important role as a signalling molecule in human melanoma. This role includes CD146 as a participant in inflammation, differentiation, adhesion, tumourigenicity, metastasis, invasion and angiogenesis among other processes, which suggests that this molecule promotes the progression of human melanoma as a multifaceted regulator. In this article, we explore the effects and corresponding mechanisms with respect to the role of CD146/MUC18 in the promotion of human melanoma progression. Collectively, the studies indicated that targeting CD146, because it is a suitable marker of poor patient outcome, might be useful in the design of future strategies for the prevention and treatment of human melanoma.
Objectives
Activation of the sympathetic system and adrenergic β‐receptors following traumatic bone defects negatively impairs bone regeneration. Whether preventing β‐receptor activation could potentially improve bone defect repair is unknown. In this study, we investigated the effect of systematic administration and local delivery of propranolol through composite scaffolds on bone healing.
Materials and methods
Collagen/PVA/propranolol/hydroxyapatite(CPPH)composite scaffolds were fabricated with 3D printing technique and characterized by scanning electron microscope (SEM). Micro‐CT analysis and bone formation histology were performed to detect new bone formation. Osteogenic differentiation of bone marrow stromal cells (BMSCs) and osteoclastogenesis of bone marrow monocytes cultured with scaffolds extract were performed for further verification.
Results
Intraperitoneal injection of propranolol did not significantly improve bone repair, as indicated by micro‐CT analysis and bone formation histology. However, CPPH scaffolds exhibited sustained release of propranolol in vitro and significantly enhanced bone regeneration compared with vehicle collagen/PVA/hydroxyapatite (CPH) scaffolds in vivo. Moreover, in vitro experiments indicated the scaffolds containing propranolol promoted the osteogenic differentiation and migration of rat BMSCs and inhibited osteoclastogenesis by preventing β‐receptor activation.
Conclusions
This study demonstrates that local adrenergic β‐receptor blockade can effectively enhance the treatment of bone defects by stimulating osteogenic differentiation, inhibiting osteoclastogenesis and enhancing BMSCs migration.
As the interface between the mother and the developing fetus, the placenta is believed to play an important role in assisted reproductive technology (ART)-induced aberrant intrauterine and postnatal development. However, the mechanisms underlying aberrant placentation remain unclear, especially during extraembryonic tissue development and early stages of placental formation. Using a mouse model, this investigation provides the first comparative proteomic analysis of in vivo (IVO) and in vitro-produced (IVP) extraembryonic tissues and placentas after IVO fertilization and development, or in vitro fertilization and culture, respectively. We identified 165 and 178 differentially expressed proteins (DEPs) between IVO and IVP extraembryonic tissues and placentas on Embryonic Day 7.5 (E7.5) and E10.5, respectively. Many DEPs were functionally associated with genetic information processing, such as impaired de novo DNA methylation, as well as posttranscriptional, translational and posttranslational dysregulation. These novel findings were further confirmed by global hypomethylation, and a lower level of correlation was found between the transcriptome and proteome in the IVP groups. In addition, numerous DEPs were involved in energy and amino acid metabolism, cytoskeleton organization and transport, and vasculogenesis and angiogenesis. These disturbed processes and pathways are likely to be associated with embryonic intrauterine growth restriction, an enlarged placenta, and impaired labyrinth morphogenesis. This study provides a direct and comprehensive reference for the further exploration of the placental mechanisms that underlie ART-induced developmental aberrations.
Assisted reproductive technology (ART) increasingly is associated with long-term side-effects on postnatal development and behaviors. High-throughput gene expression analysis has been extensively used to explore mechanisms responsible for these disorders. Our study, for the first time, provides a comparative proteomic analysis between embryos after in vivo fertilization and development (IVO, control) and in vitro fertilization and culture (IVP). By comparing the dynamic proteome during the postimplantation period, we identified 300 and 262 differentially expressed proteins (DEPs) between IVO and IVP embryos at embryonic day 7.5 (E7.5) and E10.5, respectively. Bioinformatic analysis showed many DEPs functionally associated with post-transcriptional, translational, and post-translational regulation, and these observations were consistent with correlation analysis between mRNA and protein abundance. In addition to altered gene expression due to IVP procedures, our findings suggest that aberrant processes at these various levels also contributed to proteomic alterations. In addition, numerous DEPs were involved in energy and amino acid metabolism, as well as neural and sensory development. These DEPs are potential candidates for further exploring the mechanism(s) of ART-induced intrauterine growth restriction and neurodevelopmental disorders. Moreover, significant enrichment of DEPs in pathways of neurodegenerative diseases implies the potentially increased susceptibility of ART offspring to these conditions as adults.
An injectable cell-laden nanocomposite hydrogel simulate natural ECM, promote cell proliferation, and accelerate bone healing of critical-size rat calvarial defects.
Percutaneous or transcutaneous devices are important and unique, and the corresponding biological sealing at the skin-implant interface is the key to their long-term success. Herein, we investigated the surface modification...
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