Project description:PHARC is a neurodegenerative disease comprising early onset cataract and hearing loss, retinitis pigmentosa, and involvement of both the central and peripheral nervous systems; including demyelinating sensorimotor polyneuropathy and cerebellar ataxia. Previously, we mapped this Refsum-like disorder to a 16 Mb region on chromosome 20. Here we report that mutations in the ABHD12 gene cause PHARC disease and we describe the clinical manifestations in a total of 19 patients from four different countries. The ABHD12 enzyme was recently shown to hydrolyse 2-arachidonoyl glycerol (2-AG), the main endocannabinoid lipid transmitter that acts on cannabinoid receptors CB1 and CB2. Our data therefore represent an example of an inherited disorder related to endocannabinoid metabolism. The endocannabinoid system is involved in a wide range of physiological processes including neurotransmission, mood, appetite, pain appreciation, addiction behaviour and inflammation, and several potential drugs targeting these pathways are in development for clinical applications. Our findings show that ABHD12 performs essential functions in both the central and peripheral nervous systems and the eye. Any future drug-mediated interference with this enzyme should consider the potential risk of long-term adverse effects. Homozygosity mapping using Affymetrix 250K SNP arrays were performed according to the manufacturer's directions on DNA extracted from peripheral blood samples. This accession number contains the data for families 1-5 plus 7 in the article. Supplementary files linked below. The region of interest on chromosome 20 was found using families 1 and 2. The patients in families 3,4 and 5 were then recruited and the patients were homozygous for the same region on chromosome 20 as those in families 1 and 2, showing that all these patients are distantly related. All affected are homozygous for the same mutation. The rest of the chromosomes fall outside the scope of our study. Mutations in ABHD12 Cause the Neurodegenerative Disease PHARC: An Inborn Error of Endocannabinoid Metabolism, Fiskerstrand et al. The American Journal of Human Genetics, 26 August 2010 http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B8JDD-50W2K9M-3&_user=6129429&_coverDate=08%2F26%2F2010&_rdoc=1&_fmt=high&_orig=search&_sort=d&_docanchor=&view=c&_acct=C000000150&_version=1&_urlVersion=0&_userid=6129429&md5=234296648f66debd3e2b08e795f2179f
Project description:CblX is a recently described X-linked variant of combined methylmalonic acidemia and homocystinuria, cblC type, which is the most common inborn error of intracellular cobalamin metabolism. While cblC is due to mutations in MMACHC, which is in the cobalamin metabolic pathway, cblX is caused by mutations in the transcriptional cofactor HCFC1 and its obligate transcription factor partner RONIN . Since HCFC1 and RONIN jointly regulate MMACHC transcription, cblX patients suffer from low levels of MMACHC during development and thus develop a disease highly similar to cblC. Beyond this finding, there is little else known about the other genes de-regulated in cblX and the resulting pathophysiology. Therefore, we have generated the first mouse models of this disease (Hcfc1A115V/Y and RoninF80L/F80L). We show that our cblX models exhibit the expected metabolic perturbations, along with CNS, hematopoietic and cardiac developmental defects, typically observed in cblC patients. We also uncovered a large cohort of target genes that encode ribosome protein subunits as well as unexpected phenotypes that we ascribe to deregulation of ribosome biogenesis impacting normal translation during development. In addition to identifying RONIN and HCFC1 as new transcriptional regulators of ribosome biogenesis, we establish cblX as a complex syndrome exhibiting aspects of cblC and a ribosomopathy.
Project description:PHARC is a neurodegenerative disease comprising early onset cataract and hearing loss, retinitis pigmentosa, and involvement of both the central and peripheral nervous systems; including demyelinating sensorimotor polyneuropathy and cerebellar ataxia. Previously, we mapped this Refsum-like disorder to a 16 Mb region on chromosome 20. Here we report that mutations in the ABHD12 gene cause PHARC disease and we describe the clinical manifestations in a total of 19 patients from four different countries. The ABHD12 enzyme was recently shown to hydrolyse 2-arachidonoyl glycerol (2-AG), the main endocannabinoid lipid transmitter that acts on cannabinoid receptors CB1 and CB2. Our data therefore represent an example of an inherited disorder related to endocannabinoid metabolism. The endocannabinoid system is involved in a wide range of physiological processes including neurotransmission, mood, appetite, pain appreciation, addiction behaviour and inflammation, and several potential drugs targeting these pathways are in development for clinical applications. Our findings show that ABHD12 performs essential functions in both the central and peripheral nervous systems and the eye. Any future drug-mediated interference with this enzyme should consider the potential risk of long-term adverse effects.
Project description:Anorexia and fasting are host adaptations to acute infection, inducing a metabolic switch towards ketogenesis and the production of ketone bodies, including β-hydroxybutyrate (BHB). However, whether ketogenesis metabolically influences the immune response in pulmonary infections remains unclear. Here we report impaired production of BHB in humans with SARS-CoV-2-induced but not influenza-induced acute respiratory distress syndrome (ARDS). BHB promotes the survival and the production of Interferon-g from CD4+ T cells. Using metabolic tracing analysis, we uncovered that BHB provides an alternative carbon source to fuel oxidative phosphorylation (OXPHOS) and the production of bioenergetic amino acids and glutathione, which is important for maintaining the redox balance. T cells from patients with SARS-CoV-2-induced ARDS were exhausted and skewed towards glycolysis, but can be metabolically reprogrammed by BHB to perform OXPHOS, thereby increasing their functionality. Finally, we find that ketogenic diet (KD) reduced pulmonary fibrosis, a feature particular pronounced in COVID-19 ARDS and delivery of BHB as ketone ester drink reduces the mortality of SARS-CoV-2 infected mice. Altogether, our data suggest that impaired ketogenesis in patients with SARS-CoV-2 infection accounts, at least partially for disease progression and that supplementation ketone ester might represent an easy-to-implement treatment to improve the clinical outcome of COVID-19 patients.
Project description:Manuscript describes the daily dynamics of transcriptional responses in whole blood, from acute to convalescent phase, in severe and non-severe COVID-19 patients.