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1.
Article in English | MEDLINE | ID: mdl-38997120

ABSTRACT

BACKGROUND AND PURPOSE: Incidental findings on brain MR and variation of the circle of Willis (CoW) are relatively common among the general population. Ethnic differences have been described before, but few studies have explored the prevalence of incidental intracranial cerebrovascular findings and CoW variants in the setting of a single multi-ethnic cohort. The purpose of this investigation is to describe both incidental cerebrovascular findings and the morphology of the CoW on high-resolution 3T time-of-flight MR angiography (ToF MRA) in a UK tri-ethnic population-based cohort and to present updated prevalence estimates and morphologic reference values. MATERIALS AND METHODS: We studied participants from the UK Southall and Brent Revisited (SABRE) study who underwent 3T brain MRI between 2014-2018. ToF MRA images were assessed for the presence of incidental cerebrovascular imaging findings and used to determine CoW anatomy. RESULTS: 750 participants (mean age: 71.28 ± 6.46 years, range [46-90], 337 female), 322 White Europeans, 253 South Asians, and 175 African Caribbeans, were included. Incidental cerebrovascular findings were observed in 84 subjects (11.2%, 95% CI [9.0-13.7]; 38 women, 45.24%, 95% CI [34.34-56.48]), cerebral aneurysms being the most frequent, followed by intracranial arterial stenoses (ICAS) with highest prevalence among South Asians compared to White European (OR: 2.72, 95% CI [1.22-6.08], p = .015) and African Caribbean subjects (OR: 2.79, 95% CI [1.00-7.82], p = .051). Other findings included arteriovenous malformations and infundibula. The CoW was found to be more often complete in women than in men (25.22% compared to 18.41%, p = .024), and in African Caribbean (34.86%), compared to White European (19.19%), and South Asian (14.23%) subjects (p <0.001 each). CONCLUSIONS: ICAS were independently associated with ethnicity after adjusting for vascular risk factors, having the highest prevalence among South Asians. The prevalence of aneurysms was higher than in previous population-based studies. We observed anatomical differences in the CoW configuration between women, men, and ethnicities. ABBREVIATIONS: BP = Blood pressure; ICAS = Intracranial arterial stenoses; CoW = Circle of Willis; CVM = Cerebral vascular malformations; OR = Odds ratio; ToF MRA = Time-of-flight MR angiography.

2.
Cell Rep ; 43(7): 114484, 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38990725

ABSTRACT

The inherent ability of melanoma cells to alter the differentiation-associated transcriptional repertoire to evade treatment and facilitate metastatic spread is well accepted and has been termed phenotypic switching. However, how these facets of cellular behavior are controlled remains largely elusive. Here, we show that cysteine availability, whether from lysosomes (CTNS-dependent) or exogenously derived (SLC7A11-dependent or as N-acetylcysteine), controls melanoma differentiation-associated pathways by acting on the melanocyte master regulator MITF. Functional data indicate that low cysteine availability reduces MITF levels and impairs lysosome functions, which affects tumor ferroptosis sensitivity but improves metastatic spread in vivo. Mechanistically, cysteine-restrictive conditions reduce acetyl-CoA levels to decrease p300-mediated H3K27 acetylation at the melanocyte-restricted MITF promoter, thus forming a cysteine feedforward regulation that controls MITF levels and downstream lysosome functions. These findings collectively suggest that cysteine homeostasis governs melanoma differentiation by maintaining MITF levels and lysosome functions, which protect against ferroptosis and limit metastatic spread.

4.
Fed Pract ; 41(2): 44-47, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38835923

ABSTRACT

Background: Piperacillin/tazobactam (PTZ) has been cautiously used or avoided in patients with a history of heart disease due to concern for heart failure (HF) exacerbation given its relatively high sodium content. However, no prior studies have established this association. Methods: The Antimicrobial Stewardship Team at the James H. Quillen Veterans Affairs Medical Center reviewed the use of PTZ vs the comparator antibiotic, cefepime, in 2 consecutive years to determine whether the use of PTZ was more likely to be associated with acute decompensation of HF. Records of 389 veterans hospitalized in 2018 and 2019 were reviewed and included in this study. Results: Acute decompensation of HF was significantly associated with the use of PTZ (n = 25; 12.3%) compared with cefepime (n = 4; 2.2%) (P < .001). Additionally, hospital readmissions due to HF were higher in the PTZ group compared with the cefepime group (11 vs 1, P = .02). There were no significant differences identified in the length of stay or overall mortality between 204 patients who received PTZ compared with 185 patients who received cefepime (P = .54 and P = .63, respectively). Conclusions: PTZ use was significantly associated with a higher incidence of acute decompensation of HF and hospital readmission with HF exacerbation compared with cefepime. PTZ use among hospitalized patients with a history of HF should be carefully monitored or avoided.

5.
Biochim Biophys Acta Mol Cell Res ; 1871(6): 119754, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38762172

ABSTRACT

Peroxisome biogenesis disorders are caused by pathogenic variants in genes involved in biogenesis and maintenance of peroxisomes. However, mitochondria are also often affected in these diseases. Peroxisomal membrane proteins, including PEX14, have been found to mislocalise to mitochondria in cells lacking peroxisomes. Recent studies indicated that this mislocalisation contributes to mitochondrial abnormalities in PEX3-deficient patient fibroblasts cells. Here, we studied whether mitochondrial morphology is also affected in PEX3-deficient HEK293 cells and whether PEX14 mislocalises to mitochondria in these cells. Using high-resolution imaging techniques, we show that although endogenous PEX14 mislocalises to mitochondria, mitochondrial morphology was normal in PEX3-KO HEK293 cells. However, we discovered that overexpression of tagged PEX14 in wild-type HEK293 cells resulted in its mitochondrial localisation, accompanied by altered mitochondrial morphology. Our data indicate that overexpression of tagged PEX14 alone directly or indirectly cause mitochondrial abnormalities in cells containing peroxisomes.


Subject(s)
Membrane Proteins , Mitochondria , Peroxisomes , Humans , Mitochondria/metabolism , Mitochondria/genetics , Membrane Proteins/metabolism , Membrane Proteins/genetics , HEK293 Cells , Peroxisomes/metabolism , Peroxisomes/genetics , Peroxins/metabolism , Peroxins/genetics , Protein Transport , Lipoproteins , Repressor Proteins
6.
Nat Aging ; 4(5): 681-693, 2024 May.
Article in English | MEDLINE | ID: mdl-38609524

ABSTRACT

Studies in preclinical models suggest that complex lipids, such as phospholipids, play a role in the regulation of longevity. However, identification of universally conserved complex lipid changes that occur during aging, and how these respond to interventions, is lacking. Here, to comprehensively map how complex lipids change during aging, we profiled ten tissues in young versus aged mice using a lipidomics platform. Strikingly, from >1,200 unique lipids, we found a tissue-wide accumulation of bis(monoacylglycero)phosphate (BMP) during mouse aging. To investigate translational value, we assessed muscle tissue of young and older people, and found a similar marked BMP accumulation in the human aging lipidome. Furthermore, we found that a healthy-aging intervention consisting of moderate-to-vigorous exercise was able to lower BMP levels in postmenopausal female research participants. Our work implicates complex lipid biology as central to aging, identifying a conserved aging lipid signature of BMP accumulation that is modifiable upon a short-term healthy-aging intervention.


Subject(s)
Aging , Exercise , Muscle, Skeletal , Humans , Animals , Aging/metabolism , Female , Mice , Muscle, Skeletal/metabolism , Exercise/physiology , Male , Lipidomics , Lysophospholipids/metabolism , Physical Conditioning, Animal/physiology , Aged , Lipid Metabolism/physiology , Monoglycerides/metabolism , Adult , Middle Aged
7.
Cell Stem Cell ; 31(5): 676-693.e10, 2024 May 02.
Article in English | MEDLINE | ID: mdl-38626772

ABSTRACT

Frontotemporal dementia (FTD) is an incurable group of early-onset dementias that can be caused by the deposition of hyperphosphorylated tau in patient brains. However, the mechanisms leading to neurodegeneration remain largely unknown. Here, we combined single-cell analyses of FTD patient brains with a stem cell culture and transplantation model of FTD. We identified disease phenotypes in FTD neurons carrying the MAPT-N279K mutation, which were related to oxidative stress, oxidative phosphorylation, and neuroinflammation with an upregulation of the inflammation-associated protein osteopontin (OPN). Human FTD neurons survived less and elicited an increased microglial response after transplantation into the mouse forebrain, which we further characterized by single nucleus RNA sequencing of microdissected grafts. Notably, downregulation of OPN in engrafted FTD neurons resulted in improved engraftment and reduced microglial infiltration, indicating an immune-modulatory role of OPN in patient neurons, which may represent a potential therapeutic target in FTD.


Subject(s)
Frontotemporal Dementia , Neurons , Osteopontin , tau Proteins , Osteopontin/metabolism , Osteopontin/genetics , Frontotemporal Dementia/genetics , Frontotemporal Dementia/pathology , Frontotemporal Dementia/metabolism , Humans , Neurons/metabolism , Neurons/pathology , Animals , tau Proteins/metabolism , Mice , Neuroinflammatory Diseases/metabolism , Neuroinflammatory Diseases/pathology , Microglia/metabolism , Microglia/pathology , Mutation/genetics
8.
Biochim Biophys Acta Mol Basis Dis ; 1870(5): 167177, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38636615

ABSTRACT

Mevalonate kinase deficiency (MKD) is an autosomal recessive metabolic disorder associated with recurrent autoinflammatory episodes. The disorder is caused by bi-allelic loss-of-function variants in the MVK gene, which encodes mevalonate kinase (MK), an early enzyme in the isoprenoid biosynthesis pathway. To identify molecular and cellular consequences of MKD, we studied primary fibroblasts from severely affected patients with mevalonic aciduria (MKD-MA) and more mildly affected patients with hyper IgD and periodic fever syndrome (MKD-HIDS). As previous findings indicated that the deficient MK activity in MKD impacts protein prenylation in a temperature-sensitive manner, we compared the subcellular localization and activation of the small Rho GTPases RhoA, Rac1 and Cdc42 in control, MKD-HIDS and MKD-MA fibroblasts cultured at physiological and elevated temperatures. This revealed a temperature-induced altered subcellular localization and activation in the MKD cells. To study if and how the temperature-induced ectopic activation of these signalling proteins affects cellular processes, we performed comparative transcriptome analysis of control and MKD-MA fibroblasts cultured at 37 °C or 40 °C. This identified cell cycle and actin cytoskeleton organization as respectively most down- and upregulated gene clusters. Further studies confirmed that these processes were affected in fibroblasts from both patients with MKD-MA and MKD-HIDS. Finally, we found that, similar to immune cells, the MK deficiency causes metabolic reprogramming in MKD fibroblasts resulting in increased expression of genes involved in glycolysis and the PI3K/Akt/mTOR pathway. We postulate that the ectopic activation of small GTPases causes inappropriate signalling contributing to the molecular and cellular aberrations observed in MKD.


Subject(s)
Fibroblasts , Mevalonate Kinase Deficiency , Mevalonate Kinase Deficiency/genetics , Mevalonate Kinase Deficiency/metabolism , Mevalonate Kinase Deficiency/pathology , Humans , Fibroblasts/metabolism , Fibroblasts/pathology , Phosphotransferases (Alcohol Group Acceptor)/genetics , Phosphotransferases (Alcohol Group Acceptor)/metabolism , Phosphotransferases (Alcohol Group Acceptor)/deficiency , Cells, Cultured , Signal Transduction
9.
Nat Commun ; 15(1): 2921, 2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38609362

ABSTRACT

The blue wildebeest (Connochaetes taurinus) is a keystone species in savanna ecosystems from southern to eastern Africa, and is well known for its spectacular migrations and locally extreme abundance. In contrast, the black wildebeest (C. gnou) is endemic to southern Africa, barely escaped extinction in the 1900s and is feared to be in danger of genetic swamping from the blue wildebeest. Despite the ecological importance of the wildebeest, there is a lack of understanding of how its unique migratory ecology has affected its gene flow, genetic structure and phylogeography. Here, we analyze whole genomes from 121 blue and 22 black wildebeest across the genus' range. We find discrete genetic structure consistent with the morphologically defined subspecies. Unexpectedly, our analyses reveal no signs of recent interspecific admixture, but rather a late Pleistocene introgression of black wildebeest into the southern blue wildebeest populations. Finally, we find that migratory blue wildebeest populations exhibit a combination of long-range panmixia, higher genetic diversity and lower inbreeding levels compared to neighboring populations whose migration has recently been disrupted. These findings provide crucial insights into the evolutionary history of the wildebeest, and tangible genetic evidence for the negative effects of anthropogenic activities on highly migratory ungulates.


Subject(s)
Antelopes , Animals , Antelopes/genetics , Ecosystem , Africa, Eastern , Africa, Southern , Anthropogenic Effects
10.
Commun Med (Lond) ; 4(1): 58, 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38532017

ABSTRACT

BACKGROUND: Natural cytokines are poorly suited as therapeutics for systemic administration due to suboptimal pharmacological and pharmacokinetic (PK) properties. Recombinant human interleukin-2 (rhIL-2) has shown promise for treatment of autoimmune (AI) disorders yet exhibits short systemic half-life and opposing immune responses that negate an appropriate therapeutic index. METHODS: A semi-synthetic microbial technology platform was used to engineer a site-specifically pegylated form of rhIL-2 with enhanced PK, specificity for induction of immune-suppressive regulatory CD4 + T cells (Tregs), and reduced stimulation of off-target effector T and NK cells. A library of rhIL-2 molecules was constructed with single site-specific, biorthogonal chemistry-compatible non-canonical amino acids installed near the interface where IL-2 engages its cognate receptor ßγ (IL-2Rßγ) signaling complex. Biorthogonal site-specific pegylation and functional screening identified variants that retained engagement of the IL-2Rα chain with attenuated potency at the IL-2Rßγ complex. RESULTS: Phenotypic screening in mouse identifies SAR444336 (SAR'336; formerly known as THOR-809), rhIL-2 pegylated at H16, as a potential development candidate that specifically expands peripheral CD4+ Tregs with upregulation of markers that correlate with their suppressive function including FoxP3, ICOS and Helios, yet minimally expands CD8 + T or NK cells. In non-human primate, administration of SAR'336 also induces dose-dependent expansion of Tregs and upregulated suppressive markers without significant expansion of CD8 + T or NK cells. SAR'336 administration reduces inflammation in a delayed-type hypersensitivity mouse model, potently suppressing CD4+ and CD8 + T cell proliferation. CONCLUSION: SAR'336 is a specific Treg activator, supporting its further development for the treatment of AI diseases.


Interleukin-2 (IL-2) is a protein that functions as a master regulator of immune responses. A key function of IL-2 is the stimulation of immune-regulatory cells that suppress autoimmune disease, which occurs when the body's immune system mistakenly attacks healthy tissues. However, therapeutic use of IL-2 is limited by its short duration of action and incomplete selectivity for immune-suppressive cells over off-target immune-stimulatory cells. We employ a platform that we have previously developed, which is a bacterial organism with an expanded DNA code, to identify a new version of IL-2, SAR444336 (SAR'336), with an extended duration of activity and increased selectivity for immune-suppressive cells. In mice and monkeys, SAR'336 was a specific activator of immune suppression, with minimal effect on immune cells that stimulate autoimmunity. Our results support further development of SAR'336 for treatment of autoimmune disorders.

11.
Curr Biol ; 34(7): 1576-1586.e5, 2024 04 08.
Article in English | MEDLINE | ID: mdl-38479386

ABSTRACT

Strong genetic structure has prompted discussion regarding giraffe taxonomy,1,2,3 including a suggestion to split the giraffe into four species: Northern (Giraffa c. camelopardalis), Reticulated (G. c. reticulata), Masai (G. c. tippelskirchi), and Southern giraffes (G. c. giraffa).4,5,6 However, their evolutionary history is not yet fully resolved, as previous studies used a simple bifurcating model and did not explore the presence or extent of gene flow between lineages. We therefore inferred a model that incorporates various evolutionary processes to assess the drivers of contemporary giraffe diversity. We analyzed whole-genome sequencing data from 90 wild giraffes from 29 localities across their current distribution. The most basal divergence was dated to 280 kya. Genetic differentiation, FST, among major lineages ranged between 0.28 and 0.62, and we found significant levels of ancient gene flow between them. In particular, several analyses suggested that the Reticulated lineage evolved through admixture, with almost equal contribution from the Northern lineage and an ancestral lineage related to Masai and Southern giraffes. These new results highlight a scenario of strong differentiation despite gene flow, providing further context for the interpretation of giraffe diversity and the process of speciation in general. They also illustrate that conservation measures need to target various lineages and sublineages and that separate management strategies are needed to conserve giraffe diversity effectively. Given local extinctions and recent dramatic declines in many giraffe populations, this improved understanding of giraffe evolutionary history is relevant for conservation interventions, including reintroductions and reinforcements of existing populations.


Subject(s)
Giraffes , Animals , Giraffes/genetics , Ruminants/genetics , Biological Evolution , Phylogeny , Genetic Drift
13.
Front Immunol ; 15: 1379220, 2024.
Article in English | MEDLINE | ID: mdl-38550596

ABSTRACT

Objective: Bi-allelic pathogenic variants in the MVK gene, which encodes mevalonate kinase (MK), an essential enzyme in isoprenoid biosynthesis, cause the autoinflammatory metabolic disorder mevalonate kinase deficiency (MKD). We generated and characterized MK-deficient monocytic THP-1 cells to identify molecular and cellular mechanisms that contribute to the pro-inflammatory phenotype of MKD. Methods: Using CRISPR/Cas9 genome editing, we generated THP-1 cells with different MK deficiencies mimicking the severe (MKD-MA) and mild end (MKD-HIDS) of the MKD disease spectrum. Following confirmation of previously established disease-specific biochemical hallmarks, we studied the consequences of the different MK deficiencies on LPS-stimulated cytokine release, glycolysis versus oxidative phosphorylation rates, cellular chemotaxis and protein kinase activity. Results: Similar to MKD patients' cells, MK deficiency in the THP-1 cells caused a pro-inflammatory phenotype with a severity correlating with the residual MK protein levels. In the MKD-MA THP-1 cells, MK protein levels were barely detectable, which affected protein prenylation and was accompanied by a profound pro-inflammatory phenotype. This included a markedly increased LPS-stimulated release of pro-inflammatory cytokines and a metabolic switch from oxidative phosphorylation towards glycolysis. We also observed increased activity of protein kinases that are involved in cell migration and proliferation, and in innate and adaptive immune responses. The MKD-HIDS THP-1 cells had approximately 20% residual MK activity and showed a milder phenotype, which manifested mainly upon LPS stimulation or exposure to elevated temperatures. Conclusion: MK-deficient THP-1 cells show the biochemical and pro-inflammatory phenotype of MKD and are a good model to study underlying disease mechanisms and therapeutic options of this autoinflammatory disorder.


Subject(s)
Lipopolysaccharides , Mevalonate Kinase Deficiency , Phosphotransferases (Alcohol Group Acceptor) , Humans , Lipopolysaccharides/metabolism , THP-1 Cells , Phenotype , Mevalonate Kinase Deficiency/metabolism , Oxidative Phosphorylation
14.
Nat Commun ; 15(1): 172, 2024 Jan 03.
Article in English | MEDLINE | ID: mdl-38172616

ABSTRACT

Several African mammals exhibit a phylogeographic pattern where closely related taxa are split between West/Central and East/Southern Africa, but their evolutionary relationships and histories remain controversial. Bushpigs (Potamochoerus larvatus) and red river hogs (P. porcus) are recognised as separate species due to morphological distinctions, a perceived lack of interbreeding at contact, and putatively old divergence times, but historically, they were considered conspecific. Moreover, the presence of Malagasy bushpigs as the sole large terrestrial mammal shared with the African mainland raises intriguing questions about its origin and arrival in Madagascar. Analyses of 67 whole genomes revealed a genetic continuum between the two species, with putative signatures of historical gene flow, variable FST values, and a recent divergence time (<500,000 years). Thus, our study challenges key arguments for splitting Potamochoerus into two species and suggests their speciation might be incomplete. Our findings also indicate that Malagasy bushpigs diverged from southern African populations and underwent a limited bottleneck 1000-5000 years ago, concurrent with human arrival in Madagascar. These results shed light on the evolutionary history of an iconic and widespread African mammal and provide insight into the longstanding biogeographic puzzle surrounding the bushpig's presence in Madagascar.


Subject(s)
Mammals , Humans , Animals , Swine , Madagascar , Phylogeny , Porosity , Phylogeography , Mammals/genetics
15.
Histochem Cell Biol ; 161(2): 133-144, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38243092

ABSTRACT

Peroxisomes are membrane-bounded organelles that contain enzymes involved in multiple lipid metabolic pathways. Several of these pathways require (re-)activation of fatty acids to coenzyme A (CoA) esters by acyl-CoA synthetases, which may take place inside the peroxisomal lumen or extraperoxisomal. The acyl-CoA synthetases SLC27A2, SLC27A4, ACSL1, and ACSL4 have different but overlapping substrate specificities and were previously reported to be localized in the peroxisomal membrane in addition to other subcellular locations. However, it has remained unclear if the catalytic acyl-CoA synthetase sites of these enzymes are facing the peroxisomal lumen or the cytosolic side of the peroxisomal membrane. To study this topology in cellulo we have developed a microscopy-based method that uses the previously developed self-assembling split superfolder (sf) green fluorescent protein (GFP) assay. We show that this self-assembling split sfGFP method can be used to study the localization as well as the topology of membrane proteins in the peroxisomal membrane, but that it is less suited to study the location of soluble peroxisomal proteins. With the method we could demonstrate that the acyl-CoA synthetase domains of the peroxisome-bound acyl-CoA synthetases SLC27A2 and SLC27A4 are oriented toward the peroxisomal lumen and the domain of ACSL1 toward the cytosol. In contrast to previous reports, ACSL4 was not found in peroxisomes.


Subject(s)
Coenzyme A Ligases , Peroxisomes , Coenzyme A Ligases/metabolism , Peroxisomes/metabolism , Fatty Acids/metabolism , Cytosol/metabolism , Carrier Proteins/metabolism
16.
Int J Stem Cells ; 2024 Jan 29.
Article in English | MEDLINE | ID: mdl-38281813

ABSTRACT

Inducing pluripotency in somatic cells is mediated by the Yamanaka factors Oct4, Sox2, Klf4, and c-Myc. The resulting induced pluripotent stem cells (iPSCs) hold great promise for regenerative medicine by virtue of their ability to differentiate into different types of functional cells. Specifically, iPSCs derived directly from patients offer a powerful platform for creating in vitro disease models. This facilitates elucidation of pathological mechanisms underlying human diseases and development of new therapeutic agents mitigating disease phenotypes. Furthermore, genetically and phenotypically corrected patient-derived iPSCs by gene-editing technology or the supply of specific pharmaceutical agents can be used for preclinical and clinical trials to investigate their therapeutic potential. Despite great advances in developing reprogramming methods, the efficiency of iPSC generation remains still low and varies between donor cell types, hampering the potential application of iPSC technology. This paper reviews histological timeline showing important discoveries that have led to iPSC generation and discusses recent advances in iPSC technology by highlighting donor cell types employed for iPSC generation.

17.
J Antimicrob Chemother ; 79(2): 241-254, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38073146

ABSTRACT

BACKGROUND: Antibiotics for bacteriuria and urinary tract infection are commonly prescribed during pregnancy to avoid adverse pregnancy outcomes. The aim of this study was to evaluate the association between significant bacteriuria in pregnancy and any of the four pregnancy outcomes: preterm delivery; low birth weight; small for gestational age; and preterm labour. METHODS: Systematic review with meta-analysis of observational studies. We searched PubMed, EMBASE, the Cochrane CENTRAL library, and Web of Science for observational studies published before 1 March 2022. The risk of bias was assessed using the Newcastle-Ottawa scale. Study identification, data extraction and risk-of-bias assessment was performed by two independent authors. We combined the included studies in meta-analyses and expressed results as ORs with 95% CIs (Prospero CRD42016053485). RESULTS: We identified 58 studies involving 421 657 women. The quality of the studies was mainly poor or fair. The pooled, unadjusted OR for the association between any significant bacteriuria and: (i) preterm delivery was 1.62 (95% CI: 1.30-2.01; 27 studies; I2 = 61%); (ii) low birth weight was 1.50 (95% CI: 1.30-1.72; 47 studies; I2 = 74%); (iii) preterm labour was 2.29 (95% CI: 1.53-3.43; 3 studies; I2 = 0%); and (iv) small for gestational age was 1.33 (95% CI: 0.88-2.02; 7 studies; I2 = 54%). Four studies provided an adjusted OR, but were too diverse to combine in meta-analysis. CONCLUSIONS: This systematic review identified an association between significant bacteriuria in pregnancy and the three complications: preterm delivery; low birth weight; and preterm labour. However, the quality of the available evidence is insufficient to conclude whether this association is merely due to confounding factors. There is a lack of high-quality evidence to support active identification and treatment of bacteriuria in pregnancy.


Subject(s)
Bacteriuria , Obstetric Labor, Premature , Premature Birth , Pregnancy , Infant, Newborn , Female , Humans , Premature Birth/epidemiology , Bacteriuria/epidemiology , Pregnancy Outcome , Infant, Low Birth Weight , Obstetric Labor, Premature/epidemiology
18.
Cell Stem Cell ; 31(1): 127-147.e9, 2024 01 04.
Article in English | MEDLINE | ID: mdl-38141611

ABSTRACT

Our understanding of pluripotency remains limited: iPSC generation has only been established for a few model species, pluripotent stem cell lines exhibit inconsistent developmental potential, and germline transmission has only been demonstrated for mice and rats. By swapping structural elements between Sox2 and Sox17, we built a chimeric super-SOX factor, Sox2-17, that enhanced iPSC generation in five tested species: mouse, human, cynomolgus monkey, cow, and pig. A swap of alanine to valine at the interface between Sox2 and Oct4 delivered a gain of function by stabilizing Sox2/Oct4 dimerization on DNA, enabling generation of high-quality OSKM iPSCs capable of supporting the development of healthy all-iPSC mice. Sox2/Oct4 dimerization emerged as the core driver of naive pluripotency with its levels diminished upon priming. Transient overexpression of the SK cocktail (Sox+Klf4) restored the dimerization and boosted the developmental potential of pluripotent stem cells across species, providing a universal method for naive reset in mammals.


Subject(s)
Induced Pluripotent Stem Cells , Pluripotent Stem Cells , Humans , Mice , Rats , Animals , Swine , Macaca fascicularis/metabolism , Induced Pluripotent Stem Cells/metabolism , Pluripotent Stem Cells/metabolism , Octamer Transcription Factor-3/genetics , Octamer Transcription Factor-3/metabolism , Cellular Reprogramming , SOXB1 Transcription Factors/metabolism , Cell Differentiation , Mammals/metabolism
19.
Free Radic Biol Med ; 212: 241-254, 2024 02 20.
Article in English | MEDLINE | ID: mdl-38159891

ABSTRACT

Despite the crucial role of peroxisomes in cellular redox maintenance, little is known about how these organelles transport redox metabolites across their membrane. In this study, we sought to assess potential associations between the cellular redox landscape and the human peroxisomal solute carrier SLC25A17, also known as PMP34. This carrier has been reported to function as a counter-exchanger of adenine-containing cofactors such as coenzyme A (CoA), dephospho-CoA, flavin adenine dinucleotide, nicotinamide adenine dinucleotide (NAD+), adenosine 3',5'-diphosphate, flavin mononucleotide, and adenosine monophosphate. We found that inactivation of SLC25A17 resulted in a shift toward a more reductive state in the glutathione redox couple (GSSG/GSH) across HEK-293 cells, HeLa cells, and SV40-transformed mouse embryonic fibroblasts, with variable impact on the NADPH levels and the NAD+/NADH redox couple. This phenotype could be rescued by the expression of Candida boidinii Pmp47, a putative SLC25A17 orthologue reported to be essential for the metabolism of medium-chain fatty acids in yeast peroxisomes. In addition, we provide evidence that the alterations in the redox state are not caused by changes in peroxisomal antioxidant enzyme expression, catalase activity, H2O2 membrane permeability, or mitochondrial fitness. Furthermore, treating control and ΔSLC25A17 cells with dehydroepiandrosterone, a commonly used glucose-6-phosphate dehydrogenase inhibitor affecting NADPH regeneration, revealed a kinetic disconnection between the peroxisomal and cytosolic glutathione pools. Additionally, these experiments underscored the impact of SLC25A17 loss on peroxisomal NADPH metabolism. The relevance of these findings is discussed in the context of the still ambiguous substrate specificity of SLC25A17 and the recent observation that the mammalian peroxisomal membrane is readily permeable to both GSH and GSSG.


Subject(s)
Hydrogen Peroxide , NAD , Animals , Humans , Mice , NAD/metabolism , NADP/metabolism , Glutathione Disulfide/metabolism , HeLa Cells , HEK293 Cells , Hydrogen Peroxide/metabolism , Fibroblasts/metabolism , Peroxisomes/metabolism , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Glutathione/metabolism , Oxidation-Reduction , Homeostasis , Adenine/metabolism , Mammals/metabolism
20.
J Inherit Metab Dis ; 47(2): 302-316, 2024 03.
Article in English | MEDLINE | ID: mdl-38131282

ABSTRACT

Mevalonate kinase deficiency (MKD) is an autoinflammatory metabolic disorder caused by bi-allelic loss-of-function variants in the MVK gene, resulting in decreased activity of the encoded mevalonate kinase (MK). Clinical presentation ranges from the severe early-lethal mevalonic aciduria to the milder hyper-IgD syndrome (MKD-HIDS), and is in the majority of patients associated with recurrent inflammatory episodes with often unclear cause. Previous studies with MKD-HIDS patient cells indicated that increased temperature, as caused by fever during an inflammatory episode, lowers the residual MK activity, which causes a temporary shortage of non-sterol isoprenoids that promotes the further development of inflammation. Because an increase of the residual MK activity is expected to make MKD-HIDS patients less sensitive to developing inflammatory episodes, we established a cell-based screen that can be used to identify compounds and/or therapeutic targets that promote this increase. Using a reporter HeLa cell line that stably expresses the most common MKD-HIDS variant, MK-V377I, C-terminally tagged with bioluminescent NanoLuc luciferase (nLuc), we screened the Prestwick Chemical Library®, which includes 1280 FDA-approved compounds. Multiple compounds increased MK-V377I-nLuc bioluminescence, including steroids (i.e., glucocorticoids, estrogens, and progestogens), statins and antineoplastic drugs. The glucocorticoids increased MK-V377I-nLuc bioluminescence through glucocorticoid receptor signaling. Subsequent studies in MKD-HIDS patient cells showed that the potent glucocorticoid clobetasol propionate increases gene transcription of MVK and other genes regulated by the transcription factor sterol regulatory element-binding protein 2 (SREBP-2). Our results suggest that increasing the flux through the isoprenoid biosynthesis pathway by targeting the glucocorticoid receptor or SREBP-2 could be a potential therapeutic strategy in MKD-HIDS.


Subject(s)
Mevalonate Kinase Deficiency , Humans , Mevalonate Kinase Deficiency/drug therapy , Mevalonate Kinase Deficiency/genetics , HeLa Cells , Receptors, Glucocorticoid/therapeutic use , Sterol Regulatory Element Binding Protein 1 , Phosphotransferases (Alcohol Group Acceptor)
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