Project description:Enhanced nutrition during the early calfhood period has been shown to hasten the onset of puberty in bull calves. The hypothalamic-pituitary-ovarian biochemical signalling axis regulates reproductive development in bulls, with the dynamics of the arcuate nucleus region of the hypothalamus, in particular, central to mediating the relationship between metabolic status with reproductive development. However, the precise molecular mechanisms regulating the influence of metabolic status on this signalling axis in bull calves is yet to be fully elucidated. The objective of this study was to determine the effect of an enhanced plane of nutrition during early life, up to 12 weeks of age, on the proteomic profile of the arcuate nucleus of bull calves. Bull calves were offered either a high or moderate plane of nutrition.
Project description:During the winter, hibernating mammals undergo extreme changes in physiology which allow them to survive without access to food. These animals enter a state of torpor, which is characterized by a decreased metabolism, near-freezing body temperatures, and a dramatically reduced heart rate. The neurochemical basis of this regulation is largely unknown. Based on prior evidence suggesting that the peptide-rich hypothalamus plays critical roles in hibernation, we hypothesized that changes in specific cell-cell signaling peptides (neuropeptides and peptide hormones) underlie physiological changes during torpor/arousal cycles. To test this hypothesis, we used a mass spectrometry-based peptidomics approach to examine seasonal changes of endogenous peptides that occur in the hypothalamus and pituitary of a model hibernating mammal, the thirteen-lined ground squirrel (Ictidomys tridecemlineatus). In the pituitary, we observed changes in a number of distinct peptide hormones as animals prepare for torpor in October, exit torpor in March, and progress from Spring (March) to Fall (August). In the hypothalamus, we observed an overall increase in neuropeptides in October (pre-torpor), a decrease as the animal enters torpor, and an increase in a subset of neuropeptides during normothermic interbout arousals. Notable changes were observed for feeding regulatory peptides from NPY and proSAAS prohormones, opioid peptides from PENK, PDYN, and POMC prohormones, and a number of peptides without well-established functions. In contrast to transcriptome and antibody-based measurements, our mass spectrometry-based approach allowed the identification and measurement of the final processed forms of these peptides after extensive post-translational modifications. Overall, our study provides critical insight into changes in endogenous peptides in the hypothalamus and pituitary during mammalian hibernation that were not available from transcriptome measurements. Understanding the molecular basis underlying the hibernation phenotype may pave the way for future efforts to employ hibernation-like strategies for organ preservation, combating obesity, and treatments for stroke.
Project description:In this study, we performed a comprehensive evaluation of proteomic profile in ovarian tissues of Huoyan goose during laying period compared to pre-laying period using iTRAQ based approach. 403 proteins which including 255 up-regulated and 148 down-regulated were identified. Subsequently, GO enrichment and KEGG pathway analyses of those proteins were conducted.
Project description:Perfluorooctanesulfonic acid (PFOS) is a persistent anthropogenic chemical that can affect the thyroid hormone system in humans. In experimental animals, PFOS exposure decreases thyroxine (T4) and triiodothyronine (T3) levels, without a compensatory upregulation of thyroid stimulating hormone (TSH). In adults, THs are regulated by the hypothalamus-pituitary-thyroid (HPT) axis, but also organs such as the liver and potentially the gut microbiota. PFOS and other xenobiotics can therefore potentially disrupt the TH system through various entry points of disruption. To start addressing this issue, we performed a PFOS exposure study to identify effects in multiple organs and pathways simultaneously.
Project description:Expression profile of the brain (ventral part of telenchephalon, hypothalamus and pituitary) of wild-type medaka and phod1 knockout medaka kept under short-day or long-day conditions
Project description:To examine the transcriptome, we compared the gene expression of brains (ventral part of telenchephalon, hypothalamus and pituitary) between wild type medaka and olvl28m13 knockout medaka.
Project description:The main function of the nervous system is to maintain homeostasis by sensing and reacting to signals that reach a certain threshold. For example, the brain can sense immune peripheral events through soluble compounds or the vagus nerve and can react through activation of the hypothalamus-pituitary-adrenal axis, resulting in the modulation of an ongoing immune response. Using microarrays we studied the gene expression profile of the hypothalamus in DBA/1 mice strain that developed collagen induced-arthritis vs control mice. Keywords: gene expression profile of the hypothalamus in response to induction of arthritis
Project description:The main function of the nervous system is to maintain homeostasis by sensing and reacting to signals that reach a certain threshold. For example, the brain can sense immune peripheral events through soluble compounds or the vagus nerve and can react through activation of the hypothalamus-pituitary-adrenal axis, resulting in the modulation of an ongoing immune response. Using microarrays we studied the gene expression profile of the hypothalamus in C57Bl/6 mice strain that developed collagen induced-arthritis vs control mice. Keywords: gene expression profile of the hypothalamus in response to induction of arthritis.
