Increased expression of the calcium-sensing receptor (CASR), which controls blood calcium homeostasis, leads to a decrease in the extracellular calcium set-point, thereby reducing parathyroid hormone secretion and renal calcium reabsorption and increasing calcitonin secretion resulting in reduced circulating calcium levels. Critically ill patients with elevated proinflammatory cytokine levels commonly have hypocalcemia, although the mechanism is not known.

To provide a multi-omics resource and investigate transcriptional regulatory mechanisms, we profile the transcriptome, chromatin accessibility, and methylation status of over 70,000 single nuclei (sn) from adult mouse pituitaries. Paired snRNAseq and snATACseq datasets from individual animals highlight a continuum between developmental epigenetically-encoded cell types and transcriptionally-determined transient cell states. Co-accessibility analysis-based identification of a putative Fshb cis-regulatory domain that overlaps the fertility-linked rs11031006 human polymorphism, followed by experimental validation illustrate the use of this resource for hypothesis generation. We also identify transcriptional and chromatin accessibility programs distinguishing each major cell type. Regulons, which are co-regulated gene sets sharing binding sites for a common transcription factor driver, recapitulate cell type clustering. We identify both cell type-specific and sex-specific regulons that are highly correlated with promoter accessibility, but not with methylation state, supporting the centrality of chromatin accessibility in shaping cell-defining transcriptional programs. The sn multi-omics atlas is accessible at snpituitaryatlas.princeton.edu.

Platelet-rich plasma (PRP) contains various growth factors and appears to have the potential to promote peripheral nerve regeneration, but evidence is lacking regarding its biological effect on Schwann cells (SCs). The present study was designed to investigate the effect of PRP concentration on SCs in order to determine the plausibility of using this plasma-derived therapy for peripheral nerve injury. PRP was obtained from rats by double-step centrifugation and was characterized by determining platelet numbers and growth factor concentrations. Primary cultures of rat SCs were exposed to various concentrations of PRP (40%, 20%, 10%, 5% and 2.5%). Cell proliferation assays and flow cytometry were performed to study to assess SC proliferation. Quantitative real-time PCR and ELISA analysis were performed to determine the ability of PRP to induce SCs to produce nerve growth factor (NGF) and glial cell line-derived neurotrophic factor (GDNF). Microchemotaxis assay was used to analyse the cell migration capacity. The results obtained indicated that the platelet concentration and growth factors in our PRP preparations were significantly higher than in whole blood. Cell culture experiments showed that 2.5-20% PRP significantly stimulated SC proliferation and migration compared to untreated controls in a dose-dependent manner. In addition, the expression and secretion of NGF and GDNF were significantly increased. However, the above effects of SCs were suppressed by high PRP concentrations (40%). In conclusion, the appropriate concentration of PRP had the potency to stimulate cell proliferation, induced the synthesis of neurotrophic factors and significantly increased migration of SCs dose-dependently. Copyright © 2013 John Wiley & Sons, Ltd.

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Impairments in pituitary FSH synthesis or action cause infertility. However, causes of FSH dysregulation are poorly described, in part because of our incomplete understanding of mechanisms controlling FSH synthesis. Previously, we discovered a critical role for forkhead protein L2 (FOXL2) in activin-stimulated FSH β-subunit (Fshb) transcription in immortalized cells in vitro. Here, we tested the hypothesis that FOXL2 is required for FSH synthesis in vivo. Using a Cre/lox approach, we selectively ablated Foxl2 in murine anterior pituitary gonadotrope cells. Conditional knockout (cKO) mice developed overtly normally but were subfertile in adulthood. Testis size and spermatogenesis were significantly impaired in cKO males. cKO females exhibited reduced ovarian weight and ovulated fewer oocytes in natural estrous cycles compared with controls. In contrast, ovaries of juvenile cKO females showed normal responses to exogenous gonadotropin stimulation. Both male and female cKO mice were FSH deficient, secondary to diminished pituitary Fshb mRNA production. Basal and activin-stimulated Fshb expression was similarly impaired in Foxl2 depleted primary pituitary cultures. Collectively, these data definitively establish FOXL2 as the first identified gonadotrope-restricted transcription factor required for selective FSH synthesis in vivo.

Glial cells missing-2 (GCM2) is a transcription factor expressed in the parathyroid hormone (PTH)-secreting cells of the parathyroid gland and is essential for their development. Thus far, downstream targets of GCM2 have not been identified. Here, we show that both promoters (P1 and P2) of the calcium-sensing receptor (CASR) gene, a differentiation marker for the parathyroid gland, are transactivated by wild-type GCM2. GCM response elements within CASR P1 (-451 to -441; relative to the transcription start site at +1) and CASR P2 (-166 to -156) were identified by mutated promoter-reporter studies as well as oligonucleotide precipitation assays. Primary hypoparathyroidism is a heterogeneous group of conditions characterized by hypocalcemia and hyperphosphatemia due to deficient PTH secretion. A few cases of familial isolated hypoparathyroidism with autosomal recessive inheritance have been identified that are caused by homozygous inactivating mutations in the GCM2 gene. We describe the GCM2 mutations in two families with hypoparathyroidism, one inherited in an autosomal recessive fashion and the other in an autosomal dominant manner. In transfection studies using a promoter-reporter construct having synthetic multimerized GCM elements in the promoter, the dominantly inherited mutant GCM2 exerted a dominant-negative effect on wild-type GCM2 activity, whereas recessively inherited mutants did not. In addition, we show that the transactivation of the CASR promoter-reporter constructs by wild-type GCM2 is completely abolished in the presence of the dominant-negative mutant GCM2.

Circular RNA (circRNA) is a key regulator in the development and progression of human cancers, however its role in osteosarcoma tumorigenesis is not well understood. The present study aims to investigate the expression profiles and potential modulation of circRNA on osteosarcoma carcinogenesis. Human circRNA microarray was performed to screen for abnormally expressed circRNA in osteosarcoma tissue and circRNA-0008717 was identified as one circRNA significantly upregulated in osteosarcoma tissue. Osteosarcoma patients with high circRNA-0008717 expression had shortened survival. Gain and loss functional assays suggested that knockdown of circRNA-0008717 suppressed cell proliferation, migration and invasion, but promoted cell apoptosis. By using biotin-labeled circRNA-0008717 probe to perform RNA precipitation in osteosarcoma cells, we identified miR-203 as the circ0008717-associated microRNA. Subsequently, Bmi-1 was identified as the functional target of miR-203. In addition, overexpression of circRNA-0008717 in osteosarcoma could elevate Bmi-1 expression, resulting in the promotion of osteosarcoma cell proliferation and invasion. Furthermore, the tumor promoting effect of circRNA-0008717 was abolished by miR-203 mimics or Bmi-1 silencing vector. In conclusion, circRNA-0008717 plays an oncogenic role in osteosarcoma and may serve as a promising prognostic biomarker for osteosarcoma patients. Therefore, silence of circRNA-0008717 could be a future direction to develop a novel treatment strategy.

Apigenin, identified as 4′,5,7‐trihydroxyflavone, is a natural flavonoid compound present in a variety of fruits, vegetables, functional foods, and medicinal plants. Many studies have revealed that apigenin has the cytostatic and cytotoxic effects on the various cancer cells, prevents the atherogenesis, hypertension, cardiac hypertrophy, ischemia/reperfusion‐induced heart injury, and autoimmune myocarditis, protects the chemicals‐ and ischemia/reperfusion‐induced liver injury, inhibits the asthma, bleomycin‐induced pulmonary fibrosis, abnormal behavior, and oxygen and glucose deprivation/reperfusion‐induced neural cell apoptosis, improves the pancreatitis, type 2 diabetes and its complication, osteoporosis, and collagen‐induced arthritis. These biological effects suggest that apigenin may be a potential health promoting agent. In the article, we will review these effects and possible biochemical mechanisms. Practical applications Apigenin‐rich chamomile, propolis, and garlic oil have been used in the prevention ane cure of hypertension and chemicals‐induced liver injury as food supplements. However, their bioactive components and mechanisms have not been fully elucidated. Apigenin may be a common effective component and play an important role in the process of therapy. In addition, apigenin itself may also be considered as a potential functional food, but the further development will be needed to apply to the prevention and treatment of some‐related diseases in the future.