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Cells Aug 2023The course of pathophysiological mechanisms involved in fragile X-associated tremor/ataxia syndrome (FXTAS) remains largely unknown. Previous proteomics and metabolomics...
The course of pathophysiological mechanisms involved in fragile X-associated tremor/ataxia syndrome (FXTAS) remains largely unknown. Previous proteomics and metabolomics studies conducted in blood samples collected from premutation carriers with FXTAS reported abnormalities in energy metabolism, and precursors of gluconeogenesis showed significant changes in plasma expression levels in premutation carriers who developed FXTAS. We conducted an analysis of postmortem human brain tissues from 44 donors, 25 brains with FXTAS, and 19 matched controls. We quantified the metabolite relative abundance in the inferior temporal gyrus and the cerebellum using untargeted mass spectrometry (MS)-based metabolomics. We investigated how the metabolite type and abundance relate to the number of cytosine-guanine-guanine (CGG) repeats, to markers of neurodegeneration, and to the symptoms of FXTAS. A metabolomic analysis identified 191 primary metabolites, the data were log-transformed and normalized prior to the analysis, and the relative abundance was compared between the groups. The changes in the relative abundance of a set of metabolites were region-specific with some overlapping results; 22 metabolites showed alterations in the inferior temporal gyrus, while 21 showed differences in the cerebellum. The relative abundance of cytidine was decreased in the inferior temporal gyrus, and a lower abundance was found in the cases with larger CGG expansions; oleamide was significantly decreased in the cerebellum. The abundance of 11 metabolites was influenced by changes in the CGG repeat number. A histological evaluation found an association between the presence of microhemorrhages in the inferior temporal gyrus and a lower abundance of 2,5-dihydroxypyrazine. Our study identified alterations in the metabolites involved in the oxidative-stress response and bioenergetics in the brains of individuals with FXTAS. Significant changes in the abundance of cytidine and oleamide suggest their potential as biomarkers and therapeutic targets for FXTAS.
Topics: Humans; Tremor; Brain; Cytidine; Cytosine; Guanine; Metabolomics; Ataxia; Fragile X Mental Retardation Protein
PubMed: 37681866
DOI: 10.3390/cells12172132 -
The Journal of Dermatological Treatment Dec 2023Abrocitinib, a highly selective inhibitor of Janus kinase 1 (JAK1), has been approved for the treatment of moderate-to-severe atopic dermatitis (AD). Patients with... (Review)
Review
Abrocitinib, a highly selective inhibitor of Janus kinase 1 (JAK1), has been approved for the treatment of moderate-to-severe atopic dermatitis (AD). Patients with alopecia universalis (AU) co-morbid with AD receiving abrocitinib achieved clinical remission for both diseases. We report a case of a patient with AU after drug reaction with eosinophilia and systemic symptoms (DRESS) who responded well to abrocitinib therapy at a dose of 100 and 200 mg once daily. In addition, we reviewed cases of alopecia after DRESS and explored the underlying mechanisms for alopecia areata (AA) being an autoimmune sequela. The therapeutic effects of JAK inhibitors for AA may involve downstream cytokines, such as IFN-γ and IL-15. Abrocitinib may be a promising therapeutic option for recalcitrant AU.
Topics: Humans; Alopecia Areata; Pyrimidines; Dermatitis, Atopic
PubMed: 37526039
DOI: 10.1080/09546634.2023.2242706 -
Molecular Cell Oct 2023UV irradiation induces "bulky" DNA photodimers such as (6-4)-photoproducts and cyclobutane pyrimidine dimers that are removed by nucleotide excision repair, a complex...
UV irradiation induces "bulky" DNA photodimers such as (6-4)-photoproducts and cyclobutane pyrimidine dimers that are removed by nucleotide excision repair, a complex process defective in the sunlight-sensitive and cancer-prone disease xeroderma pigmentosum. Some bacteria and lower eukaryotes can also repair photodimers by enzymatically simpler mechanisms, but such pathways have not been reported in normal human cells. Here, we have identified such a mechanism. We show that normal human cells can employ a DNA base excision repair process involving NTH1, APE1, PARP1, XRCC1, and FEN1 to rapidly remove a subset of photodimers at early times following UVC irradiation. Loss of these proteins slows the early rate of repair of photodimers in normal cells, ablates their residual repair in xeroderma pigmentosum cells, and increases UVC sensitivity ∼2-fold. These data reveal that human cells can excise photodimers using a long-patch base excision repair process that functions additively but independently of nucleotide excision repair.
Topics: Humans; Xeroderma Pigmentosum; DNA Repair; Pyrimidine Dimers; DNA Damage; DNA; Ultraviolet Rays; X-ray Repair Cross Complementing Protein 1
PubMed: 37816354
DOI: 10.1016/j.molcel.2023.09.013 -
Molecular Psychiatry Sep 2023This mirror-image study aimed to evaluate the real-life effectiveness of long-acting injectable antipsychotics (LAI) in schizophrenia. Patients with schizophrenia...
This mirror-image study aimed to evaluate the real-life effectiveness of long-acting injectable antipsychotics (LAI) in schizophrenia. Patients with schizophrenia initiating LAIs January 2015-December 2016 were enrolled from the French National Health Data System (SNDS). Standardized mean differences (SMD > 0.1 deemed clinically significant) were calculated for psychiatric healthcare resource utilization measures assessed one year before (during oral AP treatment) and one year after LAI initiation. LAI effectiveness was analyzed overall and by age group, gender and compliance to oral AP, defined as exposure to an AP for at least 80% of the year before LAI initiation. 12,373 patients were included. LAIs were more frequently initiated in men (58.1%), young (18-34 years, 42.0%) and non-compliant (63.7%) patients. LAI initiation was effective in reducing the number and duration of psychiatric hospitalizations and psychiatric emergency department (ED) admissions in non-compliant patients (SMD = -0.19, -0.26 and -0.12, respectively), but not in compliant patients. First-generation LAIs, paliperidone and aripiprazole LAIs reduced psychiatric hospitalizations (SMD = -0.20, -0.24, -0.21, respectively) and ED admissions (SMD = -0.15, -0.13, -0.15, respectively). No differences in effectiveness were found for age or gender. In compliant patients, only aripiprazole LAI reduced the number of psychiatric hospitalizations (SMD = -0.13). Risperidone and paliperidone LAIs increased hospitalization duration (SMD = 0.15 and 0.18, respectively). The prescription of LAIs (except risperidone) should be recommended in all non-compliant patients, even in women and patients aged 35 or older. The lower frequency of administration of LAIs than of oral APs may improve compliance and hence reduce the risk of relapse. Aripiprazole LAI may represent a treatment of choice for compliant patients that should be further investigated.
Topics: Male; Humans; Female; Antipsychotic Agents; Schizophrenia; Risperidone; Paliperidone Palmitate; Aripiprazole; Injections; Administration, Oral
PubMed: 37479781
DOI: 10.1038/s41380-023-02175-z -
Metabolism: Clinical and Experimental Jul 2023Thiamine (vitamin B1) is an essential cofactor in glucose metabolism, but it remains unclear whether thiamine status is lower in individuals with diabetes compared to... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Thiamine (vitamin B1) is an essential cofactor in glucose metabolism, but it remains unclear whether thiamine status is lower in individuals with diabetes compared to individuals with normal glucose metabolism.
AIMS
We conducted a systematic review and meta-analysis to study whether the circulating concentrations of various thiamine analytes differ between people with and those without diabetes.
METHODS
PubMed and the Cochrane Central Register of Controlled Trials were searched according to the study protocol. The standardized mean difference (SMD) and 95 % confidence intervals (CI) of thiamine markers between individuals with and without diabetes were used as effect size (random effects model). Subgroup analysis considered albuminuria as an additional variable.
RESULTS
Out of the 459 articles identified, 24 full-texts were eligible for the study, 20 of which qualified for the data analysis and four were evaluated for coherence. Compared to controls, individuals with diabetes showed lower concentrations of thiamine (pooled estimate SMD [95 % CI]: -0.97 [-1.89, -0.06]), thiamine monophosphate (-1.16 [-1.82, -0.50]), and total thiamine compounds (-1.01 [-1.48, -0.54]). Thiamine diphosphate (-0.72 [-1.54, 0.11] and erythrocyte transketolase activity (-0.42 [-0.90, 0.05]) tended to be lower in persons with diabetes than in controls without reaching statistical significance. Subgroup analysis showed that individuals with diabetes and albuminuria had lower thiamine levels than the controls (-2.68 [-5.34, -0.02]).
CONCLUSIONS
Diabetes is associated with lower levels of various thiamine markers, suggesting that individuals with diabetes may have higher thiamine requirements than those without diabetes, but well-designed studies are required to confirm these findings.
Topics: Humans; Thiamine; Albuminuria; Diabetes Mellitus; Thiamine Pyrophosphate; Glucose
PubMed: 37094704
DOI: 10.1016/j.metabol.2023.155565 -
Molecular Genetics and Metabolism Nov 2023Glomerular filtration rate (GFR) is commonly used in clinical practice for the diagnosis and follow-up of chronic kidney disease. Screening for inborn errors of...
Glomerular filtration rate (GFR) is commonly used in clinical practice for the diagnosis and follow-up of chronic kidney disease. Screening for inborn errors of metabolism (IEM) is based on analysis of biomarkers in urine, reported by their ratio to urinary creatinine (crn). Impaired renal function may complicate the interpretation of several biomarkers used for screening of IEM. Our goal was to investigate the influence of kidney function, in terms of measured GFR (mGFR) on purines and pyrimidines in urine, in addition to the relationship to sex, age, pH and ketosis. Children (n = 96) with chronic kidney disease (CKD), in different CKD stages, were included. Urine samples were obtained prior to the injection of iohexol. Serum samples at 7 time-points were used to calculate mGFR based on iohexol plasma clearance. The association with sex, age, ketosis and pH was examined in samples of the laboratory production from 2015 to 2021 (n = 8192). Age was a highly significant covariate for all markers. GFR correlated positively to several purines and pyrimidines; the ratios hypoxanthine/crn, xanthine/crn and urate/crn (p = 2.0 × 10, < 3 × 10 and 7.2 × 10, respectively), and the ratios orotic acid/crn, uracil/crn, and carbamyl-β-alanine/crn (p = 0.03, 1.4 × 10 and 0.003, respectively). The values of urate/crn, xanthine/crn, uracil/crn, and carbamyl-β-alanine/crn were higher in females above 16 years of age. Ketosis and pH influenced some markers. In conclusion, decreased renal function interferes with the excretion of urinary purines and pyrimidines, and this could change decision limits substantially, e.g. result in false negative results in Lesch-Nyhan syndrome. SYNOPSIS: GFR influences purines and pyrimidines in urine. Clinical Trial Registration: ClinicalTrials.gov, Identifier NCT01092260, https://clinicaltrials.gov/ct2/show/NCT01092260?term=tondel&rank=2.
Topics: Child; Female; Humans; beta-Alanine; Biomarkers; Creatinine; Iohexol; Ketosis; Kidney; Purines; Pyrimidines; Renal Insufficiency, Chronic; Uracil; Uric Acid; Male; Adolescent
PubMed: 37517327
DOI: 10.1016/j.ymgme.2023.107649 -
Current Hematologic Malignancy Reports Jun 2024Summarize best practices for management of patients with early myelofibrosis (MF). (Review)
Review
PURPOSE OF REVIEW
Summarize best practices for management of patients with early myelofibrosis (MF).
RECENT FINDINGS
Myelofibrosis is a progressive myeloproliferative neoplasm (MPN) that generally produces burdensome symptoms and ultimately leads to worse overall survival than that observed in healthy controls or patients with other MPNs. Several Janus kinase inhibitors and various interferon formulations are now available for treatment of MF, with ruxolitinib notable for extending overall survival in addition to improving MF signs and symptoms. The chronic nature of the disease can lead some patients to avoid immediate treatment in favor of a watch-and-wait approach. This review summarizes the patient management approach taken in my practice, providing guidance and a discussion of best practices with an emphasis on the importance and clinical benefits of active treatment in early MF. In particular, a case is made to consider treatment with ruxolitinib for patients with intermediate-1 risk disease and to minimize delay between diagnosis and treatment initiation for patients with intermediate or high-risk disease.
Topics: Humans; Primary Myelofibrosis; Disease Management; Pyrazoles; Pyrimidines; Nitriles; Janus Kinase Inhibitors; Practice Guidelines as Topic
PubMed: 38441783
DOI: 10.1007/s11899-024-00729-8 -
Nature Communications Feb 2024The Ataxia telangiectasia and Rad3-related (ATR) inhibitor ceralasertib in combination with the PD-L1 antibody durvalumab demonstrated encouraging clinical benefit in...
The Ataxia telangiectasia and Rad3-related (ATR) inhibitor ceralasertib in combination with the PD-L1 antibody durvalumab demonstrated encouraging clinical benefit in melanoma and lung cancer patients who progressed on immunotherapy. Here we show that modelling of intermittent ceralasertib treatment in mouse tumor models reveals CD8 T-cell dependent antitumor activity, which is separate from the effects on tumor cells. Ceralasertib suppresses proliferating CD8 T-cells on treatment which is rapidly reversed off-treatment. Ceralasertib causes up-regulation of type I interferon (IFNI) pathway in cancer patients and in tumor-bearing mice. IFNI is experimentally found to be a major mediator of antitumor activity of ceralasertib in combination with PD-L1 antibody. Improvement of T-cell function after ceralasertib treatment is linked to changes in myeloid cells in the tumor microenvironment. IFNI also promotes anti-proliferative effects of ceralasertib on tumor cells. Here, we report that broad immunomodulatory changes following intermittent ATR inhibition underpins the clinical therapeutic benefit and indicates its wider impact on antitumor immunity.
Topics: Humans; Animals; Mice; CD8-Positive T-Lymphocytes; B7-H1 Antigen; Tumor Microenvironment; Cell Line, Tumor; Immunotherapy; Disease Models, Animal; Neoplasms; Ataxia Telangiectasia Mutated Proteins; Indoles; Morpholines; Pyrimidines; Sulfonamides
PubMed: 38402224
DOI: 10.1038/s41467-024-45996-4 -
Science Bulletin Aug 2023Martynoside (MAR), a bioactive component in several well-known tonic traditional Chinese herbs, exhibits pro-hematopoietic activity during 5-fluorouracil (5-FU)...
Martynoside (MAR), a bioactive component in several well-known tonic traditional Chinese herbs, exhibits pro-hematopoietic activity during 5-fluorouracil (5-FU) treatment. However, the molecular target and the mechanism of MAR are poorly understood. Here, by adopting the mRNA display with a library of even-distribution (md-LED) method, we systematically examined MAR-protein interactions in vitro and identified the ribosomal protein L27a (RPL27A) as a key cellular target of MAR. Structural and mutational analysis confirmed the specific interaction between MAR and the exon 4,5-encoded region of RPL27A. MAR attenuated 5-FU-induced cytotoxicity in bone marrow nucleated cells, increased RPL27A protein stability, and reduced the ubiquitination of RPL27A at lys92 (K92) and lys94 (K94). Disruption of MAR binding at key residues of RPL27A completely abolished the MAR-induced stabilization. Furthermore, by integrating label-free quantitative ubiquitination proteomics, transcriptomics, and ribosome function assays, we revealed that MAR restored RPL27A protein levels and thus rescued ribosome biogenesis impaired by 5-FU. Specifically, MAR increased mature ribosomal RNA (rRNA) abundance, prevented ribosomal protein degradation, facilitated ribosome assembly, and maintained nucleolar integrity. Collectively, our findings characterize the target of a component of Chinese medicine, reveal the importance of ribosome biogenesis in hematopoiesis, and open up a new direction for improving hematopoiesis by targeting RPL27A.
Topics: Fluorouracil; Biological Assay; Bone Marrow Cells; Caffeine
PubMed: 37481436
DOI: 10.1016/j.scib.2023.07.018 -
The Journal of Biological Chemistry Dec 2023Cell proliferation requires metabolic reprogramming to accommodate biosynthesis of new cell components, and similar alterations occur in cancer cells. However, the...
Cell proliferation requires metabolic reprogramming to accommodate biosynthesis of new cell components, and similar alterations occur in cancer cells. However, the mechanisms linking the cell cycle machinery to metabolism are not well defined. Cyclin D1, along with its main partner cyclin-dependent kinase 4 (Cdk4), is a pivotal cell cycle regulator and driver oncogene that is overexpressed in many cancers. Here, we examine hepatocyte proliferation to define novel effects of cyclin D1 on biosynthetic metabolism. Metabolomic studies reveal that cyclin D1 broadly promotes biosynthetic pathways including glycolysis, the pentose phosphate pathway, and the purine and pyrimidine nucleotide synthesis in hepatocytes. Proteomic analyses demonstrate that overexpressed cyclin D1 binds to numerous metabolic enzymes including those involved in glycolysis and pyrimidine synthesis. In the glycolysis pathway, cyclin D1 activates aldolase and GAPDH, and these proteins are phosphorylated by cyclin D1/Cdk4 in vitro. De novo pyrimidine synthesis is particularly dependent on cyclin D1. Cyclin D1/Cdk4 phosphorylates the initial enzyme of this pathway, carbamoyl-phosphate synthetase 2, aspartate transcarbamylase, and dihydroorotase (CAD), and metabolomic analysis indicates that cyclin D1 depletion markedly reduces the activity of this enzyme. Pharmacologic inhibition of Cdk4 along with the downstream pyrimidine synthesis enzyme dihydroorotate dehydrogenase synergistically inhibits proliferation and survival of hepatocellular carcinoma cells. These studies demonstrate that cyclin D1 promotes a broad network of biosynthetic pathways in hepatocytes, and this model may provide insights into potential metabolic vulnerabilities in cancer cells.
Topics: Biosynthetic Pathways; Cyclin D1; Cyclin-Dependent Kinase 4; Hepatocytes; Proteomics; Pyrimidines; Humans; Animals; Mice; Cell Line
PubMed: 38152849
DOI: 10.1016/j.jbc.2023.105407