Project description:Analysis of hormone effects on irradiated LBNF1 rat testes, which contain only somatic cells except for a few type A spermatgogonia. Rats were treated for 2 weeks with either sham treatment (group X), hormonal ablation (GnRH antagonist and the androgen receptor antagonist flutamide, group XAF), testosterone supplementation (GnRH antagonist and testosterone, group XAT), and FSH supplementation ((GnRH antagonist, androgen receptor antagonist, and FSH, group XAFF). Results provide insight into identifying genes in the somatic testis cells regulated by testosterone, LH, or FSH.
Project description:Spermatogenesis requires the presence of functional somatic Sertoli cells in the seminiferous tubules of the testis. Sertoli cells provide support and factors necessary for the successful progression of germ cells into spermatozoa. Sertoli cells are regulated to a large degree by the glycoprotein hormone FSH, which is required for the testis to acquire full size and spermatogenic capacity. Signaling events initiated by the binding of FSH to its receptor lead to an alteration of Sertoli cell gene expression. To characterize the changes in gene expression in FSH-treated Sertoli cells, we used the mRNA from these cells to screen Affymetrix U34A rat GeneChip oligonucleotide microarrays. Sertoli cells from 20-d-old rats were cultured in the presence of 25 ng/ml ovine FSH. At 0, 2, 4, 8, and 24 h after the addition of FSH, total RNA was purified and used to prepare biotinylated target, which was hybridized to the U34A rat microarray containing approximately 9000 rat genes. Analysis identified 100-300 transcripts at each time point that were up-regulated or down-regulated by 2-fold or greater. Genes previously reported to be FSH or cAMP regulated in rat Sertoli cells were identified, in addition to numerous genes not reported to be expressed or FSH regulated in Sertoli cells. The expression patterns of five of these genes, encoding nerve growth factor inducible gene B, PRL-1, PC3 nerve growth factor-inducible antiproliferative putative secreted protein, diacylglycerol acyltransferase, and an expressed sequence tag, in FSH- and N,O'-dibutyryl cAMP-treated rat Sertoli cells were confirmed and characterized by Northern blot analysis. Thus, we have begun to define the transcriptome induced and repressed by FSH in rat Sertoli cells, and we have generated datasets of genes available for further analysis in regard to spermatogenesis and Sertoli cell signaling.
Project description:Knee osteoarthritis (KOA), as a degenerative multifactorial disease, affects the quality of life and mental health of patients, and also brings a huge socioeconomic burden. Treating synovitis have shown promise as anti-inflammatory therapeutics in mitigating OA symptoms and disease progression. Here, by analysing synovial single-cell sequencing (scRNA-seq) data from KOA, we found that synovial fibroblasts (FLS) in OA synovium showed a distinct pro-inflammatory phenotype. We collected synovial tissue from patients with clinical OA as well as from healthy donors, and histological examination was consistent with findings in scRNA-seq. Inspired by recent cross-tissue fibroblast lineage studies, we identified by sequencing that healthy FLS in synovial tissues share transcriptome-level similarities with dermal fibroblasts (DFb). Subsequently, we revealed the local as well as systemic distribution of intra-articular injected DFbs by constructing/extracting two types of rat fibroblasts (luciferase DFbs as well as GFP DFbs). The results demonstrate that DFbs can be locally retained in the synovium for up to three weeks following targeted engrafting on it. And intra-articular injection does not result in DFbs migration to vital organs or the occurrence of histological changes in these organs. A rat model of KOA was constructed by anterior cruciate ligament transection (ACLT) in order to study the therapeutic effect of DFbs on KOA. After injection, the rats showed improvement in painful gait. In addition, histological as well as imaging results showed reduced synovitis and improvement in articular cartilage. Finally we verified the protective effect of DFbs on cytokine-stimulated chondrocytes in a co-culture system.
Project description:To unravel the genes that underpin the effects of FSH on spermatogenesis, testicular gene expression was compared in juvenile rats after FSH suppression to littermate controls. Based on existing data, it is apparent that the dominant function of FSH shifts between 9 and 18 day postpartum (dpp) during the first wave of spermatogenesis from driving Sertoli cell proliferation to support of germ cells. To enable comprehensive analysis of the impact of acute in vivo FSH suppression on Sertoli and germ cell development and to determine the genes that underpin these affects, FSH was selectively suppressed in Sprague Dawley rats by passive immunisation for 4 days prior to testis collection at 18 days postpartum. FSH suppression did not affect Sertoli cell proliferation at 18 dpp, but germ cell numbers were decreased at 18 dpp following FSH suppression, with a corresponding increase in germ cell apoptosis measured. Sixty transcripts were measured as changed at 18 dpp in response to 4 days of FSH suppression, as assessed using Affymetrix⢠microarrays. Some of these are known as Sertoli cell-derived FSH-responsive genes (e.g. StAR, cathepsin L, insulin-like growth factor binding protein-3), while others encode proteins involved in cell cycle and survival regulation (e.g. cyclin D1, scavenger receptor class B 1). These data demonstrate that FSH affects germ cells in vivo, by supporting germ cell viability at day 18. This model enabled identification of candidate genes that contribute to the FSH-mediated pathway by which Sertoli cells support germ cells. Experiment Overall Design: Sprague Dawley male rats at day 14 postpartum received either a rat FSH antibody raised in sheep or a control sheep immunoglobulin for 4 days. RNA was extracted from the testis and hybridisation on Affymetrix microarrays was conducted.