Light microscopical and ultrastructural characterization of goat preantral follicles AbstractGoat ovarian preantral follicles were morphologically and ultrastructurally described in this work. Primordial follicles are oocytes surrounded by one layer of squamous or squamouscuboidal granulosa cells; primary follicles have a single layer of cuboidal granulosa cells, and secondary follicles are oocytes surrounded by two or more layers of cuboidal granulosa cells. At all developmental stages a thick layer of glycoproteins, the basement membrane, surrounded the preantral follicles. The quiescent oocyte is spherical or oval and it has a large eccentrically located nucleus with a conspicuous nucleolus. The organelles were uniformly distributed in the cytoplasm. A large number of vesicles were spread throughout the cytoplasm in all the oocytes. The cytoplasm of oocytes also contains numerous rounded mitochondria besides the usual organelles. As the follicle develops, the mitochondria become elongated. The communication between the oocyte and the granulosa cells is apparently mediated through endocytosis as indicated by the abundant coated pits and vesicles noted in the cortical cytoplasm of the oocyte. The oocyte plasma membrane presented projections that penetrated between adjacent granulosa cells and a few short microvilli lying parallel to the oocyte surface. In secondary follicles, patches of zona pellucida material were observed. Overall, the results indicate that the morphological and ultrastructural organization of caprine preantral follicles resembles that of other mammals. However, some particularities were observed, and that may indicate species specific differences.

Wear particle-induced osteolysis is the leading cause of aseptic loosening, which is the most common reason for THA (total hip arthroplasty) failure and revision surgery. Although existing studies suggest that osteoblast apoptosis induced by wear debris is involved in aseptic loosening, the underlying mechanism linking wear particles to osteoblast apoptosis remains almost totally unknown. In the present study, we investigated the effect of autophagy on osteoblast apoptosis induced by CoCrMo metal particles (CoPs) in vitro and in a calvarial resorption animal model. Our study demonstrated that CoPs stimulated autophagy in osteoblasts and PIO (particle-induced osteolysis) animal models. Both autophagy inhibitor 3-MA (3-methyladenine) and siRNA of Atg5 could dramatically reduce CoPs-induced apoptosis in osteoblasts. Further, inhibition of autophagy with 3-MA ameliorated the severity of osteolysis in PIO animal models. Moreover, 3-MA also prevented osteoblast apoptosis in an antiautophagic way when tested in PIO model. Collectively, these results suggest that autophagy plays a key role in CoPs-induced osteolysis and that targeting autophagy-related pathways may represent a potential therapeutic approach for treating particle-induced peri-implant osteolysis.

This study revealed the direct effects of different compositions of PRP on TSCs and provided basic scientific data to help understand the cellular and molecular mechanisms of the efficacy of PRP treatment in clinical use.

Objectives The present study aimed to investigate the overall effect of quercetin on mouse bone marrow mesenchymal stem cell (BMSC) proliferation and osteogenic differentiation in vitro. Materials and Methods BMSCs were treated with different concentrations of quercetin for 6 days. The effects of quercetin on cell proliferation were assessed at predetermined times using Cell Counting Kit-8 (CCK-8) assay. The cells were then treated with quercetin, estrogen, or an estrogen receptor (ER) antagonist (which was also administered in the presence of quercetin or estrogen) for 7 or 21 days. The effects of quercetin on BMSC osteogenic differentiation were analyzed by an alkaline phosphatase (ALP) assay kit, Alizarin Red S staining (ARS), quantitative real-time PCR (qPCR), and western blotting. Results The CCK-8 and ALP assays and ARS staining showed that quercetin significantly enhanced BMSC proliferation, ALP activity, and extracellular matrix production and mineralization, respectively. The qPCR results indicated that quercetin promoted osterix (OSX), runt-related transcription factor 2 (RUNX2), and osteopontin (OPN) transcription in the presence of osteoinduction medium, and the western blotting results indicated that quercetin enhanced bone morphogenetic protein 2 (BMP2), Smad1, Smad4, RUNX2, OSX, and OPN expression and Smad1 phosphorylation. Treatment with the ER inhibitor ICI182780 blocked the effects of quercetin. Conclusions Our data demonstrated that quercetin promotes BMSC proliferation and osteogenic differentiation. Quercetin enhances BMP signaling pathway activation and upregulates the expression of downstream genes, such as OSX, RUNX2, and OPN, via the ER.

Wear particle-induced inflammatory osteolysis is the primary cause of aseptic loosening, which is the most common reason for total hip arthroplasty (THA) failure in the med- and long term. Recent studies have suggested an important role of gut microbiota (GM) in modulating the host metabolism and immune system, leading to alterations in bone mass. Probiotic bacteria administered in adequate amounts can alter the composition of GM and confer health benefits to the host. Given the inflammatory osteolysis that occurs in wear debris-induced prosthesis loosening, we examined whether the probiotic Lactobacillus casei could reduce osteolysis in a mouse calvarial resorption model. In this study, L. casei markedly protected mice from CoCrMo particles (CoPs)-induced osteolysis. Osteoclast gene markers and the number of osteoclasts were significantly decreased in L. casei -treated mice. Probiotic treatment decreased the M1-like macrophage phenotype indicated by downregulation of tumor necrosis factor α (TNF-α), interleukin (IL)-6 and inducible nitric oxide synthase (iNOS) and increased the M2-like macrophage phenotype indicated by upregulation of IL-4, IL-10 and arginase. Collectively, these results indicated that the L. casei treatment modulated the immune status and suppressed wear particle-induced osteolysis in vivo. Thus, probiotic treatment may represent a potential preventive and therapeutic approach to reduced wear debris-induced osteolysis.

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Mesenchymal stem cells (MSCs) have several features that make them an attractive option for potentiating cartilage repair. Synovium-derived (SMSCs) have been recently recognized as an excellent source. SRY-related HMG-box (Sox) family plays an important role in the proliferation and differentiation of SMSCs. However, the role of Sox4 in human SMSCs remains elusive. In the present study, we investigated the role of Sox4 in SMSCs through gain-of-function studies and found that Sox4 promoted cell proliferation and chondrogenesis. Furthermore, Sox4 could directly bind to the promoter of long noncoding RNA DANCR and increased its expression. Finally, knockdown of DANCR could reverse the stimulative effect of Sox4 on the proliferation and chondrogenesis of SMSCs. Taken together, our data highlights the pivotal role of Sox4 in the proliferation and differentiation of SMSCs.