Vitamin C (VitC) is essential for bone health, and low VitC serum levels increase the risk for skeletal fractures. If and how VitC affects bone mineralization is unclear. Using micro-computed tomography (μCT), histologic staining, as well as quantitative backscattered electron imaging (qBEI), we assessed the effects of VitC on femoral structure and microarchitecture, bone formation, and bone mineralization density distribution (BMDD) in the VitC incompetent Gulo mouse model and wild-type mice.
View Article and Find Full Text PDFHigh-throughput microRNA sequencing was performed during differentiation of MC3T3-E1 osteoblasts to develop working hypotheses for specific microRNAs that control osteogenesis. The expression data show that miR-101a, which targets the mRNAs for the epigenetic enzyme Ezh2 and many other proteins, is highly upregulated during osteoblast differentiation and robustly expressed in mouse calvaria. Transient elevation of miR-101a suppresses Ezh2 levels, reduces tri-methylation of lysine 27 in histone 3 (H3K27me3; a heterochromatic mark catalyzed by Ezh2), and accelerates mineralization of MC3T3-E1 osteoblasts.
View Article and Find Full Text PDFBackground: The human Y chromosome harbors genes that are mainly involved in the growth, development, sexual dimorphism, and spermatogenesis process. Despite many studies, the function of the male-specific region of the Y chromosome (MSY) awaits further clarification, and a cell-based approach can help in this regard.
Results: In this study, we have developed four stable transgenic male embryonic stem cell (ESCs) lines that can overexpress male-specific genes HSFY1, RBMY1A1, RPS4Y1, and SRY.
Skeletal development and bone formation are regulated by epigenetic mechanisms that either repress or enhance osteogenic commitment of mesenchymal stromal/stem cells and osteoblasts. The transcriptional suppressive trimethylation of histone 3 lysine 27 (H3K27me3) hinders differentiation of pre-committed osteoblasts. Osteoblast maturation can be stimulated by genetic loss of the H3K27 methyltransferase Ezh2 which can also be mimicked pharmacologically using the classical Ezh2 inhibitor GSK126.
View Article and Find Full Text PDFObjective: Sexual dimorphism in mammals can be described as subsequent transcriptional differences from their distinct sex chromosome complements. Following X inactivation in females, the Y chromosome is the major genetic difference between sexes. In this study, we used a male embryonic stem cell line (Royan H6) to identify the potential role of the male-specific region of the Y chromosome (MSY) during spontaneous differentiation into embryoid bodies (EBs) as a model of early embryonic development.
View Article and Find Full Text PDFObesity promotes dysfunction and impairs the reparative capacity of mesenchymal stem/stromal cells (MSCs), and alters their transcription, protein content, and paracrine function. Whether these adverse effects are mediated by chromatin-modifying epigenetic changes remains unclear. We tested the hypothesis that obesity imposes global DNA hydroxymethylation and histone tri-methylation alterations in obese swine abdominal adipose tissue-derived MSCs compared to lean pig MSCs.
View Article and Find Full Text PDFOsteosarcomas are bone tumors that frequently metastasize to the lung. Aberrant expression of the transcription factor, runt-related transcription factor 2 (RUNX2), is a key pathological feature in osteosarcoma and associated with loss of p53 and miR-34 expression. Elevated RUNX2 may transcriptionally activate genes mediating tumor progression and metastasis, including the RUNX2 target gene osteopontin (OPN/SPP1).
View Article and Find Full Text PDFEpigenetic mechanisms control skeletal development and osteoblast differentiation. Pharmacological inhibition of the histone 3 Lys-27 (H3K27) methyltransferase enhancer of zeste homolog 2 (EZH2) in WT mice enhances osteogenesis and stimulates bone formation. However, conditional genetic loss of early in the mesenchymal lineage ( through excision via promoter-driven Cre) causes skeletal abnormalities due to patterning defects.
View Article and Find Full Text PDFEpigenetic mechanisms control phenotypic commitment of mesenchymal stromal/stem cells (MSCs) into osteogenic, chondrogenic or adipogenic lineages. To investigate enzymes and chromatin binding proteins controlling the epigenome, we developed a hybrid expression screening strategy that combines semi-automated real-time qPCR (RT-qPCR), next generation RNA sequencing (RNA-seq), and a novel data management application (FileMerge). This strategy was used to interrogate expression of a large cohort (n>300) of human epigenetic regulators (EpiRegs) that generate, interpret and/or edit the histone code.
View Article and Find Full Text PDFOsteogenic lineage commitment and progression is controlled by multiple signaling pathways (e.g., WNT, BMP, FGF) that converge on bone-related transcription factors.
View Article and Find Full Text PDFBone degenerative pathologies like osteoporosis may be initiated by age-related shifts in anabolic and catabolic responses that control bone homeostasis. Here we show that sulforaphane (SFN), a naturally occurring isothiocyanate, promotes osteoblast differentiation by epigenetic mechanisms. SFN enhances active DNA demethylation viaTet1andTet2and promotes preosteoblast differentiation by enhancing extracellular matrix mineralization and the expression of osteoblastic markers (Runx2,Col1a1,Bglap2,Sp7,Atf4, andAlpl).
View Article and Find Full Text PDFParamphistomiasis, a trematode infectious disease in ruminants, has been neglected but has recently emerged as an important cause of productivity loss. The small intestine of slaughtered sheep was collected weekly from abattoirs (Kermanshah, Sanandaj, Tabriz and Urmia Slaughterhouses) to monitoring the seasonal occurrence of Paramphistomosis, 2,421 sheep carcasses (743 male (30.69 %) and 1,678 female (69.
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