Isoleucine and valine promote prostate cancer progression via propionyl-CoA-mediated cholesterol synthesis and storage
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE272086 | GEO | 2025/07/11
REPOSITORIES: GEO
Similar Datasets
Project description:The distinctive color of brown adipose tissue (BAT) is attributed to its high content of heme-rich mitochondria. Despite this, the mechanisms by which BAT regulates intracellular heme levels remain largely unexplored. Here, we demonstrate that heme biosynthesis is the primary source of heme in brown adipocytes. Inhibiting heme biosynthesis results in an accumulation of the branched-chain amino acids (BCAAs) valine and isoleucine, due to a heme-associated metabolon that channels BCAA-derived carbons into heme biosynthesis. Heme synthesis-deficient brown adipocytes display reduced mitochondrial respiration and lower UCP1 levels compared to wild-type cells. While exogenous heme supplementation can restore intracellular heme levels and mitochondrial function, UCP1 downregulation persists. This sustained UCP1 suppression is linked to epigenetic regulation induced by the accumulation of propionyl-CoA, a byproduct of disrupted heme synthesis. Finally, disruption of heme biosynthesis in BAT impairs thermogenic response and, in female, but not male, mice, hinders the cold- induced clearance of circulating BCAAs in a sex-hormone-dependent manner. These findings establish adipose heme biosynthesis as a key regulator of thermogenesis and sex-dependent BCAA homeostasis.
2025-02-18 | GSE289295 | GEO
Project description:The distinctive color of brown adipose tissue (BAT) is attributed to its high content of heme-rich mitochondria. Despite this, the mechanisms by which BAT regulates intracellular heme levels remain largely unexplored. Here, we demonstrate that heme biosynthesis is the primary source of heme in brown adipocytes. Inhibiting heme biosynthesis results in an accumulation of the branched-chain amino acids (BCAAs) valine and isoleucine, due to a heme-associated metabolon that channels BCAA-derived carbons into heme biosynthesis. Heme synthesis-deficient brown adipocytes display reduced mitochondrial respiration and lower UCP1 levels compared to wild-type cells. While exogenous heme supplementation can restore intracellular heme levels and mitochondrial function, downregulation persists. This sustained UCP1 suppression is linked to epigenetic regulation induced by the accumulation of propionyl-CoA, a byproduct of disrupted heme synthesis. Finally, disruption of heme biosynthesis in BAT impairs thermogenic response and, in female, but not male, mice, hinders the cold- induced clearance of circulating BCAAs in a sex-hormone-dependent manner. These findings establish adipose heme biosynthesis as a key regulator of thermogenesis and sex-dependent BCAA homeostasis.
2025-02-17 | PXD060812 | Pride
Project description:Macrophages are a protective replicative niche for Mycobacterium tuberculosis (Mtb) but can kill the infecting bacterium when appropriately activated. To identify mechanisms of clearance, we compared bacterial restriction by human macrophages after treatment with 26 compounds, including some currently in clinical trials for tuberculosis. All-trans-retinoic acid (ATRA), an active metabolite of vitamin A, drove the greatest increase in Mtb control. Bacterial clearance was transcriptionally and functionally associated with changes in macrophage cholesterol trafficking and lipid metabolism. To determine how these macrophage changes affected bacterial control, we performed the first Mtb CRISPR interference screen in an infection model, identifying Mtb genes specifically required to survive in ATRA-activated macrophages. These data showed that ATRA treatment starves Mtb of cholesterol and the downstream metabolite propionyl-CoA. Supplementation with sources of propionyl-CoA, including cholesterol, abrogated the restrictive effect of ATRA. This work demonstrates that targeting the coupled metabolism of Mtb and the macrophage improves control of infection, and that it is possible to genetically map the mode of bacterial death using CRISPR interference.
2021-12-21 | GSE183912 | GEO
Project description:Methylmalonic acidemias (MMA) consist in a group of autosomal recessive inherited metabolic disorders whose pathogenesis involves the catabolism of propionyl-CoA. The propionyl-CoA produced from the degradation of cholesterol, branched-chain amino acids (valine, isoleucine, methionine, threonine) and the -oxidation of odd-chain fatty acids is converted into methylmalonyl-CoA, which is further converted in succinyl-CoA, required for energy production in the Krebs cycle. In mitochondria of MMA patients, the conversion of methylmalonyl-CoA into succinyl-CoA, catalysed by the vitamin B12-dependent methylmalonyl-CoA mutase (MUT) enzyme, is altered. This can be due to: 1) defective activity of MUT apoenzyme or 2) a defect in the synthesis or transport of adenosylcobalamin (MUT cofactor). In the first case it is referred to as isolated MMA (mut0 or mut- phenotypes if the deficiency is total or partial, respectively), while in the second case as cbl-related MMA (there is a specific disorder according to which gene is mutated) []. The blockage of this enzymatic reaction leads to increase in the levels of methylmalonic acid, hallmark of this group of diseases []. Independently from the pathogenesis, along with methylmalonic acid, other MMA-associated metabolites like acylcarnitines, amino acids and organic acids result altered in MMA [REF]. These metabolites are easily detectable and quantifiable by metabolomics approaches, such as liquid chromatography - tandem mass spectrometry (LC-MS/MS) or gas chromatography - mass spectrometry (GC-MS), in dried blood spots or urine or plasma to make diagnosis. Because of the early onset of MMA in patients, MMA is included in the panel of diseases for the expanded newborn screening in several countries, including Italy [ref]. Our work aims at understanding the mechanisms of cellular damage in MMA disease. The majority of MMA complications arise from brain damage, on which depend neurological alterations and movement disorders. In the brain, the astrocytes are damaged by hyperammonemia, causing edema and hypoperfusion. (REF lavoro) Renal function is commonly compromised in MMA patients, even the pathogenesis of kidney injury is not clear. Renal insufficiency and chronic kidney disease are partially resolved after kidney transplantation. Hyperammonemia and metabolic acidosis are considered as key mechanisms acting in the proximal tubule to lead to renal damage. In fact, general organ metabolic alterations are thought to be caused by the breakdown of branched‐chain amino acids that lead to the accumulation of circulating toxic acidic metabolites. Thus, metabolic acidosis is induced with diminishing of bicarbonate levels. Lactic acidosis and hyperammonemia result as the main metabolic alterations of MMA. (REF lavoro) Results of a previous work on a MUT-knockdown neuroblastoma cell line [Costanzo, 2018] were coherent with the disease, but did not completely elucidate such mechanisms, possibly due to limitation of the cellular model. We presumed that the transient silencing of MUT gene was not sufficient to input long-term decompensation due to absence of this protein. For this reason, we have developed a new cellular model for isolated MMA by stably knocking out MUT gene in HEK293 cell line using CRISPR/CAS9 genome editing technology. We also performed a global proteomic analysis to describe protein changes strictly connected to MUT absence and related altered pathways. Altogether, the results obtained shed new light on the molecular mechanisms of cellular damage, including alterations of cell architecture in combination with the acquisition of a higher sensitivity to stress.
2020-09-07 | PXD017977 | Pride
Project description:Fatty acid synthesis is closely linked to nutrient availability and cellular energetic status. The committed step in fatty acid synthesis is the acetyl CoA carboxylase. Eukaryotes have two genes encoding acetyl CoA carboxylases, one encoding a cytosolic enzyme and another coding for a mitochondrial enzyme. They catalyze the synthesis of malonyl CoA in the cytosol and the mitochondria, respectively. While cytosolic malonyl CoA is the precursor for fatty acid synthesis, mitochondrial malonyl CoA controls the transfer of fatty acyl group into the mitochondria by inhibiting carnitine/palmitoyl transferase activity and thus, regulates β-oxidation. In Saccharomyces cerevisiae, β-oxidation is restricted to the peroxisomes, raising the question of the function of the mitochondrial isoform (HFA1). In this study, we replaced the cytosolic Acc1 with Hfa1 expressed in the cytosol by removing the mitochondrial leader peptide, under control of the HFA1 promoter. We studied fatty acid synthesis and transcription profiles in this strain during starvation for carbon or nitrogen, using glucose or ethanol as the carbon source. Under all the conditions studied, the key sensor of energetic status, Snf1, was activated, indicating active inhibition of fatty acid synthesis. The pool size of fatty acids was smaller when Acc1 was replaced with truncated Hfa1 for fatty acid synthesis. Yet, the transcription profiles were similar in both the cases. These results point towards the conclusion that Hfa1 is either catalytically less efficient or it is more sensitive to inhibition by Snf1. Gene expression from a strain of Saccharomyces cerevisiae where cytosolic fatty acid synthesis occurs by mitochondrial acetyl CoA carboxylase (without its mitochondrial leader peptide) is compared with that in a reference strain while growing in chemostats on carbon or nitrogen starvation using glucose or ethanol as the carbon source. There are two strains (reference or mutant), two carbon sources (glucose or ethanol) and two limitations (carbon or nitrogen), resulting in 8 comparisons. Each array was performed in duplicate, resulting in 16 CEL files. Growth was limited by either carbon or nitrogen. When carbon was the limited nutrient, we tested growth on either glucose or ethanol (both using ammonium sulfate as the nitrogen source). When ammonium sulfate was limiting, we used either glucose or ethanol as the carbon source.
2010-06-08 | E-GEOD-21988 | biostudies-arrayexpress
Project description:Metabolism in cancer serves to provide energy and key biomolecules that sustain cell growth, a process that is frequently accompanied by decreased mitochondrial use of glucose. Importantly, metabolic intermediates including mitochondrial metabolites are central substrates for post-translational modifications at the core of cellular signalling and epigenetics. However, the molecular means that coordinate the use of mitochondrial metabolites for anabolism and nuclear protein modification are poorly understood. Here, we unexpectedly found that genetic and pharmacological inactivation of Pyruvate Dehydrogenase A1 (PDHA1), a subunit of pyruvate dehydrogenase complex (PDC) that regulates mitochondrial metabolism16 inhibits prostate cancer development in different mouse and human xenograft tumour models. Intriguingly, we found that lipid biosynthesis was strongly affected in prostate tumours upon PDC inactivation. Mechanistically, we found that nuclear PDC controls the expression of Sterol regulatory element-binding transcription factor (SREBF) target genes by mediating histone acetylation whereas mitochondrial PDC provides cytosolic citrate for lipid synthesis in a coordinated effort to sustain anabolism. In line with the oncogenic function of PDC in prostate cancer, we find that PDHA1 and the PDC activator, Pyruvate dehydrogenase phospatase 1 (PDP1), are frequently amplified and overexpressed at both gene and protein level in these tumours. Taken together, our findings demonstrate that both mitochondrial and nuclear PDC sustains prostate tumourigenesis by controlling lipid biosynthesis thereby pointing at this complex as a novel target for cancer therapy.
2018-02-21 | GSE74245 | GEO
Project description:β-caryophyllene (BCP) exhibits anti-proliferative properties in cancer cells. Here, we examine the hypothesis that BCP induces membrane remodeling. Our data show that high concentrations of BCP increase membrane permeability of human breast cells (hBrC) causing detachment and cell death. At a “sub-lethal” concentration of BCP, we show that BCP induces a striking upregulation of genes involved in cholesterol biosynthesis, including the gene that encodes for HMGCoA reductase (HMGCR), the rate-determining step in cholesterol biosynthesis. In addition, stearoyl-CoA desaturase (SCD) is also upregulated which would lead to the enhanced formation of monounsaturated fatty acids, specifically oleate and palmitoleate from stearoyl CoA and palmitoyl CoA, respectively. These fatty acids are major components of membrane phospholipids and cholesterol esters. Together, these data suggest that cells respond to BCP by increasing the synthesis of components found in membranes. These responses could be viewed as a repair mechanism and/or as a mechanism to mount resistance to the cytotoxic effect of BCP. Blocking HMGCR enhances the cytotoxicity of BCP, suggesting that this may provide an additional therapeutic tool in controlling breast cancer cell growth, assuming that targeted specificity could be established.
2019-12-01 | GSE125511 | GEO
Project description:Fatty acid synthesis is closely linked to nutrient availability and cellular energetic status. The committed step in fatty acid synthesis is the acetyl CoA carboxylase. Eukaryotes have two genes encoding acetyl CoA carboxylases, one encoding a cytosolic enzyme and another coding for a mitochondrial enzyme. They catalyze the synthesis of malonyl CoA in the cytosol and the mitochondria, respectively. While cytosolic malonyl CoA is the precursor for fatty acid synthesis, mitochondrial malonyl CoA controls the transfer of fatty acyl group into the mitochondria by inhibiting carnitine/palmitoyl transferase activity and thus, regulates β-oxidation. In Saccharomyces cerevisiae, β-oxidation is restricted to the peroxisomes, raising the question of the function of the mitochondrial isoform (HFA1). In this study, we replaced the cytosolic Acc1 with Hfa1 expressed in the cytosol by removing the mitochondrial leader peptide, under control of the HFA1 promoter. We studied fatty acid synthesis and transcription profiles in this strain during starvation for carbon or nitrogen, using glucose or ethanol as the carbon source. Under all the conditions studied, the key sensor of energetic status, Snf1, was activated, indicating active inhibition of fatty acid synthesis. The pool size of fatty acids was smaller when Acc1 was replaced with truncated Hfa1 for fatty acid synthesis. Yet, the transcription profiles were similar in both the cases. These results point towards the conclusion that Hfa1 is either catalytically less efficient or it is more sensitive to inhibition by Snf1. Gene expression from a strain of Saccharomyces cerevisiae where cytosolic fatty acid synthesis occurs by mitochondrial acetyl CoA carboxylase (without its mitochondrial leader peptide) is compared with that in a reference strain while growing in chemostats on carbon or nitrogen starvation using glucose or ethanol as the carbon source.
2010-05-25 | GSE21988 | GEO
Project description:Heteromeric acetyl-CoA carboxylase (ACCase) catalyzes the ATP-dependent carboxylation of acetyl-CoA to produce malonyl-CoA, the committed step for de novo fatty acid synthesis. In plants, ACCase activity is controlled at multiple levels, including negative regulation by biotin attachment domain-containing (BADC) proteins, of which the badc1/3 double mutant leads to increased seed triacylglycerol accumulation. Unexpectedly, the Arabidopsis badc1/3 mutant also accumulates more protein. The metabolic consequences from both higher oil and protein were investigated in developing badc1/3 seed using global transcriptomics, translatomics, proteomics, metabolomics and other biomass measurements. Changes included increased storage proteins and lipid-droplet packaging proteins, increased SDP1 lipase, altered organic acid metabolism, and reduced extracellular lipid synthesis perhaps offsetting the increase in TAG. We present a model of how Arabidopsis adapted to deregulated ACCase, resulting in more oil, and altered flux through pathways that partition carbon and propose targets for future bioengineering of seed storage reserves.
2025-02-28 | GSE278842 | GEO
Project description:Cholesterol of the host macrophage membrane is vital for mycobacterial infection, replication, and persistence. During chronic infection within host lung tissues, cholesterol facilitates the phagocytosis of mycobacteria into macrophages. Cholesterol degradation leads to increased flux of acetyl-coenzyme A (CoA) and propionyl-CoA, providing energy and building blocks for virulence macromolecules as well as donors for global protein acylation. Potential functions of lysine acylation are gradually revealed in bacterial survival and pathogenesis. However, the mycobacterial proteome and posttranslational modification (PTM) changes involved in the cholesterol catabolism bioprocess remain unclear. Here, we used nonpathogenic Mycobacterium smegmatis as a model and simultaneously monitored mycobacterial proteome and acetylome changes in the presence of glucose and cholesterol. We discovered that cholesterol metabolic enzymes were upregulated with respect to both protein expression levels and lysine acylation levels during the metabolic shift from glucose to cholesterol. After that, adenylating enzymes related to cholesterol metabolism were proven to be precisely regulated at the propionylation level by mycobacterial acyltransferase M. smegmatis Kat (MsKat) in response to cellular propionyl-CoA accumulation. Furthermore, the kinase expression and phosphorylation levels were also changed along with fluctuations in cholesterol levels. Our results expanded current knowledge of acylation regulation in the cholesterol catabolism of mycobacteria and provided references for possible antimycobacterium strategy.IMPORTANCE Cholesterol assimilation is a critical step in mycobacterial chronic infection. However, knowledge from the dynamic characterization of cholesterol metabolism in mycobacteria at the protein expression and PTM levels remains limited. Our study uncovered the landscape of protein expression, lysine acetylation, lysine propionylation, and S/T/Y phosphorylation during the metabolic changes from glucose to cholesterol in mycobacteria. The data showed that cholesterol-induced carbon shift resulted in the elevation of protein expression and lysine acylation in diverse metabolic enzymes involved in cholesterol degradation and that the presence of cholesterol also promoted the perturbations at the phosphorylation level in the kinase system in mycobacteria. This study systematically characterized the regulation of cholesterol catabolism at several different levels, which provided the detailed references in mycobacterial proteome and potential antimycobacterial strategies.
2019-12-03 | PXD014366 |