Project description:The obesity incidence is increasing worldwide with the urgent need to identify new therapeutics. Obesity is associated with endocrine alterations, arising from changes in the hypothalamic-pituitary hormone axes, leading to reproductive disorders, altered basal metabolism and stress hormone production. The focus of this study was to determine if diet induced obesity alters pituitary gland plasticity, gene expression and hormone production and secretion. Here we performed single cell RNA-sequencing (scRNA-seq) on pituitary glands from control (CTRL) and high fat diet (HFD) fed males and looked at cell type population dynamics and gene expression changes between HFD and CTRL for all hormone-producing cell types. Our study revealed diet-induced changes in pituitary gland plasticity and hormone production that may play a role in altered hormone production in obese patients and consequently, dysregulation of pituitary gland homeostasis.
Project description:NR5A1 is expressed in the pituitary gonadotropes and regulates their functional differentiation. We have previously identified a pituitary-specific enhancer region located in the 6th intron of the Nr5a1 gene. In this study, deletion of the pituitary enhancer by genome editing abolished the expression of NR5A1 in the pituitary gland, confirming the functional importance of the enhancer. Transcriptomic changes in the enhancer-deleted mouse pituitary were revealed in both males and females.
Project description:Overproduction of adrenal hormones causes obesity and hypertension, whereas adrenalectomy (ADX) leads to weight loss and hypotension. The pituitary gland is a major target organ for the adrenal hormones. To identify potential mediators for the effect of ADX on pituitary system regulating weight loss and hypotension, we investigated the effect of ADX on pituitary gene expression using serial analysis of gene expression (SAGE). The numbers of analyzed SAGE tag were 126688 tags for intact mice (n = 51) and 59482 tags for ADX mice (n = 12), which corresponded to 45151 and 21790 distinct tag species, respectively. Thirty-three pituitary genes were differentially expressed between intact and ADX mice. Three genes encoding for pro-opiomelanocortin have been upregulated by ADX. The ADX has induced the gene expression of growth hormone while downregulating an expressed sequence tag similar to (EST) growth hormone. The ADX reduced the expression of genes involved in mitochondrial oxidative phosphorylation, such as NADH dehydrogenase 3 and cytochrome c oxidase 3, whereas neuromedin B gene were dramatically induced. In addition, the ADX increased the expression levels of other three genes involved in hormone release (response to metastatic cancers 1), extracellular matrix (matrix gamma-carboxyglutamate gla protein), and cation transport (solute carrier family member 17). Moreover, one functionally-uncharacterized and 20 novel transcripts were significantly modulated by ADX. Thus the current study has revealed the alterations in the pituitary gene expression that may play key roles in the mechanisms of ADX-induced weight loss and hypotension. Keywords: adrenalectomy, serial analysis of gene expression Rodents and pituitary gland sampling. Male C57BL6 mice were obtained from Charles River Laboratories (St. Constant, QC, Canada), at 12-14 weeks of age. Mice were housed in an air-conditioned room (19-25?) with controlled lighting from 07:15 to 19:15 h and were given free access to food (Lab Rodent Diet No. 5002) and water. One week prior to sampling of pituitary gland, adrenalectomy was performed in mice of ADX groups (n = 12). The ADX mice received sodium chloride (0.9g/dl) in their drinking water after the surgery. All mice were killed between 08:30 and 12:30 by decapitation under isoflurane anesthesia. Brain was removed from the skull and the pituitary gland was immediately dissected. The pituitary gland was immediately frozen in liquid nitrogen, pooled together for each group, and stored at -80? until RNA extraction.
Project description:The regulation of pituitary function via the hypothalamus and via intra-pituitary connections represents a complex system. Though hormones secreted from the pituitary glands have been well studied, overall information of proteins expressed in the pituitary glands is very limited. Protein expression profiling of normal pituitary tissue may lead to discovery of novel proteins playing an important role in the physiology of pituitary glands and can lead to better understanding of pituitary gland diseases. We aimed to carry out systematic proteomic profiling of adenohypophysis from human pituitary glands using high-resolution Fourier transform mass spectrometer. A total of 2,175 proteins were identified in this study of which, 105 proteins were identified for the first time as compared to high throughput proteomic-based studies from human pituitary glands. The comprehensive list of proteins identified in this study will facilitate the better understanding the role of this important gland in health and disease.