Publications by authors named "Gillian P Johnson"

Follicle-stimulating hormone (FSH) is a key endocrine regulator of ovarian function. FSH is secreted as 2 macroglycosylation variants: partially glycosylated FSH (FSH21/18) and fully glycosylated FSH (FSH24). FSH21/18 is more potent than FSH24 at binding to and activating the FSH receptor (R).

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Article Synopsis
  • The main question of the study is whether a special type of human hormone called hypo-glycosylated FSH (hFSH18/21) is better at helping ovaries grow compared to the regular type (hFSH24).
  • The results show that hypo-glycosylated FSH is more effective, leading to healthier and larger follicles in mice, thanks to better signaling in their bodies.
  • The study involved giving different types of this hormone to young female mice and examining how their ovaries responded to it.
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The benefits of physical loading to skeletal mass are well known. The primary cilium has emerged as an important organelle in bone mechanobiology/mechanotransduction, particularly in mesenchymal stem/stromal cells, yet the molecular mechanisms of cilium mechanotransduction are poorly understood. In this study, we demonstrate that Gpr161 is a mechanoresponsive GPCR, that localises to the cilium, and is involved in fluid shear-induced cAMP signalling and downstream osteogenesis.

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Bone marrow stromal/stem cells represent a quiescent cell population that replenish the osteoblast bone-forming cell pool with age and in response to injury, maintaining bone mass and repair. A potent mediator of stromal/stem cell differentiation in vitro and bone formation in vivo is physical loading, yet it still remains unclear whether loading-induced bone formation requires the osteogenic differentiation of these resident stromal/stem cells. Therefore, in this study, we utilized the leptin receptor (LepR) to identify and trace the contribution of bone marrow stromal cells to mechanoadaptation of bone in vivo.

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Bone formation or regeneration requires the recruitment, proliferation, and osteogenic differentiation of stem/stromal progenitor cells. A potent stimulus driving this process is mechanical loading. Osteocytes are mechanosensitive cells that play fundamental roles in coordinating loading-induced bone formation via the secretion of paracrine factors.

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Gonadotropin hormones and their receptors play a central role in the control of male and female reproduction. In recent years, there has been growing evidence surrounding the complexity of gonadotropin hormone/receptor signaling, with it increasingly apparent that the Gαs/cAMP/PKA pathway is not the sole signaling pathway that confers their biological actions. Here we review recent literature on the different receptor-receptor, receptor-scaffold, and receptor-signaling molecule complexes formed and how these modulate and direct gonadotropin hormone-dependent intracellular signal activation.

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Lower back pain is a commonly reported symptom during pregnancy. However, herniated lumbar disk disease is an uncommon cause for such pain. Cauda equina syndrome (CES) during pregnancy is a rare clinical scenario.

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Background: Physical loading is necessary to maintain bone tissue integrity. Loading-induced fluid shear is recognised as one of the most potent bone micromechanical cues and has been shown to direct stem cell osteogenesis. However, the effect of pressure transients, which drive fluid flow, on human bone marrow stem cell (hBMSC) osteogenesis is undetermined.

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Mechanical loading is a potent stimulus of bone adaptation, requiring the replenishment of the osteoblast from a progenitor population. One such progenitor is the mesenchymal stem cell (MSC), which undergoes osteogenic differentiation in response to oscillatory fluid shear. Yet, the mechanism mediating stem cell mechanotransduction, and thus the potential to target this therapeutically, is poorly understood.

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Skeletal homeostasis requires the continued replenishment of the bone forming osteoblast from a mesenchymal stem cell (MSC) population, a process that has been shown to be mechanically regulated. However, the mechanisms by which a biophysical stimulus can induce a change in biochemical signaling, mechanotransduction, is poorly understood. As a precursor to loading-induced bone formation, deciphering the molecular mechanisms of MSC osteogenesis is a critical step in developing novel anabolic therapies.

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Cation channels of sperm (CatSper) are sperm-specific calcium channels with identified roles in the regulation of sperm function in humans, mice, and horses. We sought to employ a comparative genomics approach to identify conserved CATSPER genes in the bovine genome, and profile their expression in reproductive tissue. We hypothesized that CATSPER proteins expressed in bull testicular tissue mediates sperm hyperactivation and their rheotactic response in the reproductive tract of the cow.

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?-defensins are small cationic proteins with potent immunoregulatory and antimicrobial activity. The number of genes encoding these peptides varies significantly between and within species but they have not been extensively characterised in the horse. Here, we describe a systematic search of the Equus caballus genome that identified a cluster of novel ?-defensin genes on Chromosome 22, which is homologous to a cluster on bovine Chromosome 13.

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