Project description:<p>21-hydroxylase deficiency (21-OHD) is an inherited disorder that results from a mutation on the CYP21A2 gene. It affects the adrenal glands and is the most common cause of congenital adrenal hyperplasia (CAH). 21-OHD CAH causes the body to produce an insufficient amount of cortisol and an excess of androgen, the type of hormone that produces male characteristics. The primary treatment for 21-OHD CAH, glucocorticoid replacement therapy, has been shown to cause bone loss. However, the elevated hormone levels caused by 21-OHD CAH may increase production of the protein osteoprotegerin (OPG), which in turn may protect against bone loss. This study will compare bone density and OPG levels in women who have 21-OHD CAH and have undergone a lifetime of glucocorticoid replacement therapy to that in women who have neither of these criteria. In doing so, the study will aim to determine the relationship between OPG and bone loss.</p> <p>Because of the excess of androgen caused by 21-OHD CAH, women with CAH may exhibit some male-like characteristics. Glucocorticoids are a member of a class of drugs called corticosteroids, which are used in hormone replacement therapy. In order to counteract the effects of 21-OHD CAH, women with the disease are given hormone replacement therapy with glucocorticoids beginning at infancy. Glucocorticoids are known to cause bone loss. Despite many years of treatment with glucocorticoids, however, young women with 21-OHD CAH seem to be protected against bone loss. Researchers believe that the increased androgen levels in these women lead to increased estrogen levels, which in turn increase OPG production. The increase in OPG levels may protect women against bone loss. This study will evaluate bone density and OPG levels in women with and without 21-OHD CAH to determine the relationship between OPG and bone loss.</p> <p>Participants in this observational study will attend only one study visit. At this visit, they will undergo a blood draw; a scan of their lower spine, hip, and forearm; height and weight measurements; and a body fat analysis test. This last test will entail a weak and painless electrical signal being sent from foot to foot. Participants will not attend any follow-up visits for this study.</p>
Project description:Background: Glycogen Storage Disease (GSD) Type Ia and Ib are rare metabolic diseases caused by gene variants in G6PC and SLC37A4 respectively. Patients often suffer from multiple metabolic abnormalities and severe long-term complications. Methods: In this study, we employed comprehensive untargeted proteomics on retrospectively registered samples: 26 serum/plasma samples (18 GSD Ia and 8 GSD Ib) from patients with 21 matched healthy controls, complemented by 4 liver samples from 3 patients who received liver transplantation (3 from GSD Ia including 1 with hepatocellular carcinoma tissue and 1 from GSD Ib), compared to 10 donor liver samples, to investigate the pathological mechanisms of disease complications and identify potential biomarkers. Results: Pathway analysis of the differentially regulated proteins revealed distinct changes in the serum/plasma of GSD Ia and Ib. Coagulation was the most significantly changed biological process in the GSD Ia patients. Immune response-associated proteins, especially a large number of immunoglobulins, increased in GSD Ib specifically. Proteins related to liver injury, cholesterol, and amyloidosis were altered in two subtypes, though more pronounced in GSD Ia. Potential biomarkers with significant alterations both in the circulation as well as in the liver were identified specifically for monitoring and prognosing GSD Ia (COL163 and PROC), GSD Ib (F11 and CD163), and hepatocellular carcinoma (HCC) in GSD Ia patients (ALDOB and CFHR5). Conclusions: These findings provide new insights into the pathogenesis of GSD I-related complications and highlighted the potential of protein circulating biomarkers for monitoring complication progression in GSD Ia and Ib, as well as for assessing HCC risk in GSD Ia patients.
Project description:Glycogen storage disease type Ia (GSD Ia) is a rare autosomal recessive disorder caused by a deficiency in glucose 6-phosphatase-α (G6PC). Patients primarily suffer from failure to thrive, hepatomegaly and severe fasting intolerance, biochemically characterized by hypoketotic and hyperlipidemia. Since they display clinical heterogeneity in biochemical symptoms and long-term hepatic complications, preclinical exploration of pathophysiological mechanisms and biomarkers is imperative for better prognosis and monitoring. To achieve this, an untargeted proteomics workflow was employed for identifying protein changes in liver and plasma from liver-specific G6pc knockout GSD Ia mice under fed and fasted conditions. Providing a link between the disease effects of GSD Ia in the liver and how these liver-specific effects present in the circulation under controlled (fed) and metabolic dysregulation (fasted) conditions. In liver proteomics results, protein levels related to the metabolism of glucose and lipids were up-regulated in GSD Ia mice versus controls. Differences were also observed in the proteasome, ribosome, NAD+ metabolism, hepatocellular detoxification, and synthesis of genotoxicity substances.. In plasma proteomics, proteins associated with complement and coagulation cascades decreased in GSD Ia.. The differences in both the liver and plasma were in general more pronounced in fasted GSD Ia mice. The overlapping differentially regulated plasma and liver proteins were subsequently identified for their potential as plasma biomarkers of hepatic complications, namely early-stage liver failure (SERPINA1E, C8b, and MBL2) non-alcoholic fatty liver disease (GPI1, UGP2, ALDOB, ACLY and FASN) and early hepatocellular carcinoma (PSMA4, PSMA7, PSMB5, and SDHA).
Project description:abstract1: Glycogen storage disease type Ia (GSD Ia) is an inborn error of metabolism caused by defective glucose-6-phosphatase (G6PC) activity. GSD Ia patients exhibit severe hepatomegaly due to glycogen and triglyceride (TG) accumulation in the liver. We have previously shown that the activity of Carbohydrate Response Element Binding Protein (ChREBP), a key regulator of glycolysis and de novo lipogenesis, is increased in GSD Ia. In the current study we assessed the contribution of ChREBP to non-alcoholic fatty liver disease (NAFLD) development in a mouse model for hepatic GSD Ia. PMID : 32083759 Abstract2:Glycogen storage disease type 1a (GSD Ia) is an inborn error of metabolism caused by a defect in glucose-6-phosphatase (G6PC) activity, which induces severe hepatomegaly and increases the risk for liver cancer in patients. Hepatic GSD Ia is characterized by constitutive activation of Carbohydrate Response Element Binding Protein (ChREBP), a glucose-sensitive transcription factor that has been proposed as a pro-oncogenic molecular switch that supports tumour progression. Here we studied the contribution of ChREBP signalling on liver disease progression and tumour susceptibility in a mouse model for GSD Ia. Hepatocyte-specific G6pc knockout (L-G6pc-/-) mice were treated with AAV-shChREBP to normalize hepatic ChREBP activity. Hepatic ChREBP normalization induced dysplastic liver growth, massively increased hepatocyte size and sensitized to hepatic inflammation and liver fibrosis in GSD Ia mice. Furthermore, the nuclear levels of the oncoprotein YAP were increased and its transcriptional targets were induced in ChREBP normalized GSD Ia mice. Hepatic ChREBP normalization furthermore induced DNA damage and mitotic activity in GSD Ia mice, while chromosomal instability, cGAS-STING pathway, senescence, and hepatocyte dedifferentiation gene signatures emerged. Upon ChREBP silencing in immortalized human hepatocytes, on the other hand, the induction of YAP target gene expression was paralleled by cell cycle arrest, cell death, and reduced proliferation. In conclusion, our findings indicate that ChREBP activity limits hepatomegaly while protecting against liver disease progression and hepatocellular tumour induction in GSD Ia. These results underline the importance to establish the context-specific roles of ChREBP to define its therapeutic potential. PMID:37085901
Project description:Osteoporosis and bone fractures affect millions of men and women worldwide and are often due to increased bone resorption (bone loss) mediated by osteoclasts. Here, we identify a novel role for the cytoplasmic protein ELMO1 as an important ‘signaling node’ controlling the bone resorption function of osteoclasts. Initially, we noted association of ELMO1 SNPs with bone abnormalities and altered bone density in humans. Experimentally, ELMO1 emerged as a promoter of bone loss wherein deletion of ELMO1 reversed osteoporosis / bone erosions in four in vivo mouse models: osteoprotegerin deficiency, ovariectomy, and two types of inflammatory arthritis. However, ELMO1 did not promote bone loss under homeostatic conditions. Mechanistic studies pointed to a larger ELMO1 signaling network that regulates osteoclast activity at several levels. First, transcriptomics coupled with CRISPR/Cas9 genetic deletion approaches identified new regulators of osteoclast function associated with Elmo1. Second, defining the ‘ELMO1 interactome’ in osteoclasts via proteomics revealed proteins linked to bone degradation. Third, ELMO1 affects the formation of the actin ring /sealing zone on bone-like surfaces and the distribution of osteoclast-specific proteases. Finally, a 3D structure-based inhibitory peptide targeting a highly conserved region of ELMO1 reduced bone resorption in wild type osteoclasts. Collectively, these data identify ELMO1 as a signaling hub that regulates osteoclast function and bone loss, with relevance to diseases such as osteoporosis and arthritis.
Project description:Long-Term Outcome in Offspring and Mothers of Dexamethasone-Treated Pregnancies at Risk for Classical Congenital Adrenal Hyperplasia Owing to 21-Hydroxylase Deficiency - GSD 5610
Project description:Long-Term Outcome in Offspring and Mothers of Dexamethasone-Treated Pregnancies at Risk for Classical Congenital Adrenal Hyperplasia Owing to 21-Hydroxylase Deficiency - GSD 5610