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1.
bioRxiv ; 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39386701

RESUMO

Background: Although the ability of the heart to adapt to environmental stress has been studied extensively, the molecular and cellular mechanisms responsible for cardioprotection are not yet fully understood. Methods: We administered Toll-like receptor (TLR) agonists or a diluent to wild-type mice and assessed their potential to induce cardiac protection against injury from a high intraperitoneal dose of isoproterenol (ISO) administered 7 days later. Cardioprotective effects were analyzed through serum cardiac troponin I levels, immune cell profiling via flow cytometry, echocardiography, and multiomic single-nuclei RNA and ATAC sequencing. Results: Pretreatment with the TLR4 agonist lipopolysaccharide (LPS), but not TLR1/2 or TLR3 agonists, conferred cardioprotection against ISO, as demonstrated by reduced cardiac troponin I leakage, decreased inflammation, preservation of cardiac structure and function, and improved survival. Remarkably, LPS-induced tolerance was reversed by ß-glucan treatment. Multiomic analysis showed that LPS-tolerized hearts had greater chromatin accessibility and upregulated gene expression compared to hearts treated with LPS and ß-glucan (reverse-tolerized). The LPS tolerance was associated with upregulation of interferon response pathways across various cell types, including cardiac myocytes and stromal cells. Blocking both type 1 and type 2 interferon signaling eliminated LPS-induced tolerance against ISO, while pretreatment with recombinant type 1 and 2 interferons conferred cardiac protection. Multiomic sequencing further revealed enhanced cytoprotective signaling in interferon-treated hearts. Analysis of cell-cell communication networks indicated increased autocrine signaling by cardiac myocytes, as well as greater paracrine signaling between stromal cells and myeloid cells, in LPS-tolerized versus reverse-tolerized hearts. Conclusions: LPS pretreatment confers cardiac protection against ISO-induced injury through TLR4 mediated type 1 and 2 interferon signaling, consistent with trained innate immune tolerance. The observation that LPS-induced protection in cardiac myocytes involves both cell-autonomous and non-cell-autonomous mechanisms underscores the complexity of innate immune tolerance in the heart, warranting further investigation into this cardioprotective phenotype. Clinical Perspective: What is new?: The Toll-like receptor 4 (TLR4) agonist lipopolysaccharide (LPS) confers cardiac protection against isoproterenol-mediated injury in a manner consistent with trained innate immune tolerance, which is reversed by ß-glucan treatment.Activation of type 1 and 2 interferon signaling, which is downstream of Toll-like receptor 4, is necessary and sufficient for LPS-induced cardiac protection.LPS-tolerized hearts show heightened autocrine signaling by cardiac myocytes and, to a greater degree, increased cell-cell communication between cardiac myocytes and stromal and myeloid cells compared to reverse-tolerized hearts.What are the clinical implications?: TLR4 and interferon signaling play key roles in the establishment of cardiac protection and LPS-induced trained innate immune tolerance.The protective effects of LPS are mediated by cell-autonomous and non-cell-autonomous mechanisms, suggesting that a deeper understanding of the molecular and cellular signatures of innate immune tolerance is required for the development of targeted approaches to modulate trained innate immunity, and consequently cytoprotection, in the heart.

2.
bioRxiv ; 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39386719

RESUMO

Calibrated transcriptional outputs in cellular signaling require fine regulation of transcription factor activity. In vertebrate Hedgehog (Hh) signaling, the precise output of the final effectors, the GLI (Glioma-associated-oncogene) transcription factors, depends on the primary cilium. In particular, the formation of the activator form of GLI upon pathway initiation requires its concentration at the distal cilium tip. However, the mechanisms underlying this critical step in Hh signaling are unclear. We developed a real-time imaging assay to visualize GLI2, the primary GLI activator isoform, at single particle resolution within the cilium. We observed that GLI2 is a cargo of Intraflagellar Transport (IFT) machinery and is transported with anterograde bias during a restricted time window following pathway activation. Our findings position IFT as a crucial mediator of transcription factor transport within the cilium for vertebrate Hh signaling, in addition to IFT's well-established role in ciliogenesis. Surprisingly, a conserved Hh pathway regulator, the atypical non-motile kinesin KIF7, is critical for the temporal control of GLI2 transport by IFT and the spatial control of GLI2 localization at the cilium tip. This discovery underscores the collaborative role of a motile and a non-motile cilium-specific cytoskeletal system in determining the transcriptional output during Hh signaling.

3.
Front Immunol ; 15: 1483400, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39372401

RESUMO

Lactate significantly impacts immune cell function in sepsis and septic shock, transcending its traditional view as just a metabolic byproduct. This review summarizes the role of lactate as a biomarker and its influence on immune cell dynamics, emphasizing its critical role in modulating immune responses during sepsis. Mechanistically, key lactate transporters like MCT1, MCT4, and the receptor GPR81 are crucial in mediating these effects. HIF-1α also plays a significant role in lactate-driven immune modulation. Additionally, lactate affects immune cell function through post-translational modifications such as lactylation, acetylation, and phosphorylation, which alter enzyme activities and protein functions. These interactions between lactate and immune cells are central to understanding sepsis-associated immune dysregulation, offering insights that can guide future research and improve therapeutic strategies to enhance patient outcomes.


Assuntos
Ácido Láctico , Transportadores de Ácidos Monocarboxílicos , Sepse , Humanos , Sepse/imunologia , Sepse/metabolismo , Ácido Láctico/metabolismo , Animais , Transportadores de Ácidos Monocarboxílicos/metabolismo , Transportadores de Ácidos Monocarboxílicos/imunologia , Biomarcadores , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/imunologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/imunologia , Processamento de Proteína Pós-Traducional , Proteínas Musculares/metabolismo , Proteínas Musculares/imunologia , Simportadores/metabolismo , Simportadores/imunologia
4.
Front Bioeng Biotechnol ; 12: 1304622, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39351064

RESUMO

Selecting and implementing a tissue clearing protocol is challenging. Established more than 100 years ago, tissue clearing is still a rapidly evolving field of research. There are currently many published protocols to choose from, and each performs better or worse across a range of key evaluation factors (e.g., speed, cost, tissue stability, fluorescence quenching). Additionally, tissue clearing protocols are often optimized for specific experimental contexts, and applying an existing protocol to a new problem can require a lengthy period of adaptation by trial and error. Although the primary literature and review articles provide a useful starting point for optimization, there is growing recognition that results can vary dramatically with changes to tissue type or antibody used. To help address this issue, we have developed a novel, freely available repository of tissue clearing protocols named T-CLEARE (Tissue CLEAring protocol REpository; https://doryworkspace.org/doryviz). T-CLEARE incorporates community responses to an open survey designed to capture details not commonly found in the scientific literature, including modifications to published protocols required for specific use cases and instances when tissue clearing protocols did not perform well (negative results). The goal of T-CLEARE is to help the community share evaluations and modifications of tissue clearing protocols for various tissue types and potentially identify best-in-class methods for a given application.

5.
bioRxiv ; 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39386465

RESUMO

Only persistent HPV infections lead to the development of cancer. Thus, understanding the virus-host interplay that influences the establishment of viral infection has important implications for HPV biology and human cancers. The ability of papillomaviruses to establish in cells requires the strict temporal regulation of viral gene expression in sync with cellular differentiation. This control primarily happens at the level of RNA splicing and polyadenylation. However, the details of how this spatio-temporal regulation is achieved still need to be fully understood. Until recently, it has been challenging to study the early events of the HPV lifecycle following infection. We used a single-cell genomics approach to identify cellular factors involved in viral infection and establishment. We identify protein arginine N-methyltransferase 1 (PRMT1) as an important factor in viral infection of primary human cervical cells. PRMT1 is the main cellular enzyme responsible for asymmetric dimethylation of cellular proteins. PRMT1 is an enzyme responsible for catalyzing the methylation of arginine residues on various proteins, which influences processes such as RNA processing, transcriptional regulation, and signal transduction. In this study, we show that HPV18 infection leads to increased PRMT1 levels across the viral lifecycle. PRMT1 is critical for the establishment of a persistent infection in primary cells. Mechanistically, PRMT1 inhibition leads to a highly dysregulated viral splicing pattern. Specifically, reduced PRMT1 activity leads to intron retention and a change in the E6 and E7 expression ratio. In the absence of PRMT1, viral transcripts are destabilized and subject to degradation via the nonsense-mediated decay (NMD) pathway. These findings highlight PRMT1 as a critical regulator of the HPV18 lifecycle, particularly in RNA processing, and position it as a potential therapeutic target for persistent HPV18 infections.

6.
medRxiv ; 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39371163

RESUMO

Pediatric Long COVID has been associated with a wide variety of symptoms, conditions, and organ systems, but distinct clinical presentations, or subphenotypes, are still being elucidated. In this exploratory analysis, we identified a cohort of pediatric (age <21) patients with evidence of Long COVID and no pre-existing complex chronic conditions using electronic health record data from 38 institutions and used an unsupervised machine learning-based approach to identify subphenotypes. Our method, an extension of the Phe2Vec algorithm, uses tens of thousands of clinical concepts from multiple domains to represent patients' clinical histories to then identify groups of patients with similar presentations. The results indicate that cardiorespiratory presentations are most common (present in 54% of patients) followed by subphenotypes marked (in decreasing order of frequency) by musculoskeletal pain, neuropsychiatric conditions, gastrointestinal symptoms, headache, and fatigue.

7.
N Engl J Med ; 391(14): 1287-1301, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39383458

RESUMO

BACKGROUND: Gene therapy with elivaldogene autotemcel (eli-cel) consisting of autologous CD34+ cells transduced with lentiviral vector containing ABCD1 complementary DNA (Lenti-D) has shown efficacy in clinical studies for the treatment of cerebral adrenoleukodystrophy. However, the risk of oncogenesis with eli-cel is unclear. METHODS: We performed integration-site analysis, genetic studies, flow cytometry, and morphologic studies in peripheral-blood and bone marrow samples from patients who received eli-cel therapy in two completed phase 2-3 studies (ALD-102 and ALD-104) and an ongoing follow-up study (LTF-304) involving the patients in both ALD-102 and ALD-104. RESULTS: Hematologic cancer developed in 7 of 67 patients after the receipt of eli-cel (1 of 32 patients in the ALD-102 study and 6 of 35 patients in the ALD-104 study): myelodysplastic syndrome (MDS) with unilineage dysplasia in 2 patients at 14 and 26 months; MDS with excess blasts in 3 patients at 28, 42, and 92 months; MDS in 1 patient at 36 months; and acute myeloid leukemia (AML) in 1 patient at 57 months. In the 6 patients with available data, predominant clones contained lentiviral vector insertions at multiple loci, including at either MECOM-EVI1 (MDS and EVI1 complex protein EVI1 [ecotropic virus integration site 1], in 5 patients) or PRDM16 (positive regulatory domain zinc finger protein 16, in 1 patient). Several patients had cytopenias, and most had vector insertions in multiple genes within the same clone; 6 of the 7 patients also had somatic mutations (KRAS, NRAS, WT1, CDKN2A or CDKN2B, or RUNX1), and 1 of the 7 patients had monosomy 7. Of the 5 patients with MDS with excess blasts or MDS with unilineage dysplasia who underwent allogeneic hematopoietic stem-cell transplantation (HSCT), 4 patients remain free of MDS without recurrence of symptoms of cerebral adrenoleukodystrophy, and 1 patient died from presumed graft-versus-host disease 20 months after HSCT (49 months after receiving eli-cel). The patient with AML is alive and had full donor chimerism after HSCT; the patient with the most recent case of MDS is alive and awaiting HSCT. CONCLUSIONS: Hematologic cancer developed in a subgroup of patients who were treated with eli-cel; the cases are associated with clonal vector insertions within oncogenes and clonal evolution with acquisition of somatic genetic defects. (Funded by Bluebird Bio; ALD-102, ALD-104, and LTF-304 ClinicalTrials.gov numbers, NCT01896102, NCT03852498, and NCT02698579, respectively.).


Assuntos
Adrenoleucodistrofia , Terapia Genética , Vetores Genéticos , Neoplasias Hematológicas , Lentivirus , Adolescente , Criança , Feminino , Humanos , Masculino , Adrenoleucodistrofia/terapia , Adrenoleucodistrofia/genética , Membro 1 da Subfamília D de Transportadores de Cassetes de Ligação de ATP/genética , Evolução Clonal/genética , Seguimentos , Terapia Genética/efeitos adversos , Terapia Genética/métodos , Vetores Genéticos/administração & dosagem , Vetores Genéticos/efeitos adversos , Neoplasias Hematológicas/epidemiologia , Neoplasias Hematológicas/genética , Lentivirus/genética , Síndromes Mielodisplásicas/epidemiologia , Síndromes Mielodisplásicas/genética
8.
N Engl J Med ; 391(14): 1302-1312, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39383459

RESUMO

BACKGROUND: Cerebral adrenoleukodystrophy is a severe form of X-linked adrenoleukodystrophy characterized by white-matter disease, loss of neurologic function, and early death. Elivaldogene autotemcel (eli-cel) gene therapy, which consists of autologous CD34+ cells transduced with Lenti-D lentiviral vector containing ABCD1 complementary DNA, is being tested in persons with cerebral adrenoleukodystrophy. METHODS: In a phase 2-3 study, we evaluated the efficacy and safety of eli-cel therapy in boys with early-stage cerebral adrenoleukodystrophy and evidence of active inflammation on magnetic resonance imaging (MRI). The primary efficacy end point was survival without any of six major functional disabilities at month 24. The secondary end points included overall survival at month 24 and the change from baseline to month 24 in the total neurologic function score. RESULTS: A total of 32 patients received eli-cel; 29 patients (91%) completed the 24-month study and are being monitored in the long-term follow-up study. At month 24, none of these 29 patients had major functional disabilities; overall survival was 94%. At the most recent assessment (median follow-up, 6 years), the neurologic function score was stable as compared with the baseline score in 30 of 32 patients (94%); 26 patients (81%) had no major functional disabilities. Four patients had adverse events that were directly related to eli-cel. Myelodysplastic syndrome (MDS) with excess blasts developed in 1 patient at month 92; the patient underwent allogeneic hematopoietic stem-cell transplantation and did not have MDS at the most recent follow-up. CONCLUSIONS: At a median follow-up of 6 years after lentiviral gene therapy, most patients with early cerebral adrenoleukodystrophy and MRI abnormalities had no major functional disabilities. However, insertional oncogenesis is an ongoing risk associated with the integration of viral vectors. (Funded by Bluebird Bio; ALD-102 and LTF-304 ClinicalTrials.gov numbers NCT01896102 and NCT02698579, respectively.).


Assuntos
Membro 1 da Subfamília D de Transportadores de Cassetes de Ligação de ATP , Adrenoleucodistrofia , Terapia Genética , Vetores Genéticos , Lentivirus , Adolescente , Criança , Pré-Escolar , Humanos , Masculino , Adrenoleucodistrofia/diagnóstico , Adrenoleucodistrofia/genética , Adrenoleucodistrofia/mortalidade , Adrenoleucodistrofia/terapia , Membro 1 da Subfamília D de Transportadores de Cassetes de Ligação de ATP/genética , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Terapia Genética/efeitos adversos , Terapia Genética/métodos , Vetores Genéticos/administração & dosagem , Vetores Genéticos/efeitos adversos , Transplante de Células-Tronco Hematopoéticas , Lentivirus/genética , Imageamento por Ressonância Magnética , Seguimentos , Resultado do Tratamento , Síndromes Mielodisplásicas/epidemiologia , Síndromes Mielodisplásicas/genética
9.
J Am Heart Assoc ; 13(19): e033844, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39344598

RESUMO

BACKGROUND: Discrimination may contribute to sleep health disparities among women, yet limited research has investigated the association between discrimination and insomnia with short sleep. METHODS AND RESULTS: Among a racially and ethnically diverse sample of women (N=25 920; mean age, 72.2±6.1 years), we investigated the relationship of discrimination with insomnia symptoms and sleep duration. Poisson models with robust variance were fit to examine discrimination with insomnia, sleep duration (short <7 hours or long >9 hours versus recommended 7-9 hours), and insomnia short sleep phenotype adjusted for covariates. Insomnia symptoms, short and long sleep, and high discrimination were reported by 53%, 11%, 15%, and 40% of women, respectively. Women reporting high versus low discrimination were more likely to report insomnia, short sleep, and insomnia short sleep phenotype (insomnia: adjusted prevalence ratio, 1.15 [95% CI, 1.13-1.18]; short sleep: adjusted prevalence ratio, 1.24 [95% CI, 1.16-1.34]; insomnia short sleep phenotype: adjusted prevalence ratio, 1.45 [95% CI, 1.31-1.61]). In exploratory analyses, the association between discrimination and insomnia symptoms was present among Asian and White women, whereas the association between discrimination and sleep duration was among Hispanic (long sleep) and White (short sleep) women. Further, the association between discrimination and insomnia symptoms was more pronounced among those with less than a bachelor's degree, whereas women with a bachelor's degree or higher were less vulnerable to the association between discrimination and long sleep. CONCLUSIONS: Discrimination was associated with insomnia and short sleep, a more severe phenotype for adverse cardiovascular health. Discrimination may be a target for reducing sleep problems among older women.


Assuntos
Distúrbios do Início e da Manutenção do Sono , Humanos , Feminino , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Distúrbios do Início e da Manutenção do Sono/fisiopatologia , Idoso , Fatores de Tempo , Prevalência , Sono , Fatores de Risco , Disparidades nos Níveis de Saúde , Idoso de 80 Anos ou mais , Estados Unidos/epidemiologia , Qualidade do Sono , Estudos Transversais , Duração do Sono
10.
Blood Adv ; 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39293082

RESUMO

Hematopoietic stem cell transplantation with lentiviral vector (LVV) transduced autologous cells has proven an effective therapeutic strategy for sickle cell disease (SCD). However, ex vivo culture or proliferative stress associated with in vivo reconstitution may amplify any underlying genetic risk of leukemia. We aimed to minimize culture-induced stress and reduce genomic damage during ex vivo culture, enhance stem cell fitness and reconstitution of SCD CD34+ cells transduced with BCL11A shmiR-encoding LVV currently in clinical trials (NCT NCT03282656). UM171, a pyrimidoindole derivative can expand normal hematopoietic stem cells (HSCs) during in vitro culture and has been shown to be safe and effective in clinical trials using umbilical cord blood (NCT02668315). We examined the effect of UM171 during ex vivo LVV transduction of SCD HSCs. Culture of SCD CD34+ HSCs with UM171 during transduction reduced DNA damage and reactive oxygen species (ROS), decreased apoptosis, and was associated with increased numbers of immunophenotypically defined long-term HSCs. UM171 increased the engraftment of LVV transduced human HSCs in immunodeficient mice and barcode tracing revealed increased clonal diversity of engrafting cells. In competitive transplantation assays, analysis of BM showed that cells transduced in the presence of UM171 consistently outcompeted those transduced under control conditions. In summary, exposure of SCD peripheral blood CD34+ cells to UM171 during LVV transduction enhances stem cell fitness. These findings suggest manufacturing of genetically modified HSCs in the presence of UM171 may improve efficacy, safety and sustainability of gene therapy utilizing ex vivo approaches.

11.
ACR Open Rheumatol ; 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39236308

RESUMO

OBJECTIVE: There are numerous reports of people substituting medical cannabis (MC) for medications. Our obejctive was to investigate the degree to which this substitution occurs among people with rheumatic conditions. METHODS: In a secondary analysis from a cross-sectional survey conducted with patient advocacy groups in the US and Canada, we investigated MC use and medication substitution among people with rheumatic conditions. We subgrouped by whether participants substituted MC for medications and investigated differences in perceived symptom changes and use patterns, including methods of ingestion, cannabinoid content (cannabidiol vs delta-9-tetrahydrocannabinol [THC]), and use frequency. RESULTS: Among 763 participants, 62.5% reported substituting MC products for medications, including nonsteroidal anti-inflammatory drugs (54.7%), opioids (48.6%), sleep aids (29.6%), and muscle relaxants (25.2%). Following substitution, most participants reported decreases or cessation in medication use. The primary reasons for substitution were fewer adverse effects, better symptom management, and concerns about withdrawal symptoms. Substitution was associated with THC use and significantly higher symptom improvements (including pain, sleep, anxiety, and joint stiffness) than nonsubstitution, and a higher proportion of substitutors used inhalation routes than those who did not. CONCLUSION: Although the determination of causality is limited by our cross-sectional design, these findings suggest that an appreciable number of people with rheumatic diseases substitute medications with MC for symptom management. Inhalation of MC products containing some THC was most commonly identified among those substituting, and disease characteristics did not differ by substitution status. Further study is needed to better understand the role of MC for symptom management in rheumatic conditions.

12.
iScience ; 27(9): 110754, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39280606

RESUMO

The presence of precursor to exhausted (Tpex) CD8+ T cells is important to maintain robust immunity following treatment with immune checkpoint inhibition (ICI). Impressive responses to ICI are emerging in patients with stage II-III mismatch repair (MMR)-deficient (dMMR) colorectal cancer (CRC). We found 64% of dMMR and 15% of mismatch repair-proficient (pMMR) stage III CRCs had a high frequency of tumor infiltrating lymphocytes (TIL-hi). Furthermore, expression of TCF-1 (Tcf7) by CD8+ T cells predicted improved patient prognosis and Tpex cells (CD3+CD8+TCF-1+PD-1+) were abundant within lymphoid aggregates of stage III CRCs. In contrast, CD3+CD8+TCF-1-PD-1+ cells were more abundant at the invasive front and tumor core, while γδ T cells were equally abundant in all tumor areas. Interestingly, no differences in the frequency of Tpex cells were observed between TIL-hi dMMR and TIL-hi pMMR CRCs. Therefore, Tpex cell function and ICI response rates in TIL-hi CRC warrants further investigation.

13.
bioRxiv ; 2024 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-39314414

RESUMO

Recognizing and responding to threat cues is essential to survival. In rats, freezing is the most common behavior measured. Previously we demonstrated a threat cue can organize diverse behaviors (Chu et al., 2024). However, the experimental design of Chu et al. (2024) was complex and the findings descriptive. Here, we gave female and male Long Evans rats simple paired or unpaired presentations of a light and foot shock (8 total) in a conditioned suppression setting, using a range of shock intensities (0.15, 0.25, 0.35 or 0.5 mA). We found that conditioned suppression was only observed at higher foot shock intensities (0.35 mA and 0.5 mA). We constructed comprehensive, temporal ethograms by scoring 22,272 frames of behavior for 12 mutually exclusive behavior categories in 200 ms intervals around cue presentation. A 0.5 mA and 0.35 mA shock-paired visual cue suppressed reward seeking, rearing and scaling, as well as light-directed rearing and light-directed scaling. The shock-paired visual paired cue further elicited locomotion and freezing. Linear discriminant analyses showed that ethogram data could accurately classify rats into paired and unpaired groups. Considering the complete ethogram data produced superior classification than considering subsets of behaviors. The results demonstrate diverse threat-elicited behaviors - in a simple Pavlovian fear conditioning design - containing sufficient information to distinguish the fear learning status of individual rats.

14.
mSphere ; : e0057524, 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39315809

RESUMO

To adapt to various host microenvironments, the human fungal pathogen Candida albicans possesses the capacity to accumulate and store glycogen as an internal carbohydrate source. In the model yeast Saccharomyces cerevisiae, ScGlc7p and ScGac1p are the serine/threonine type 1 protein phosphatase catalytic and regulatory subunits that control glycogen synthesis by altering the phosphorylation state of the glycogen synthase Gsy2p. Despite recent delineation of the glycogen synthesis pathway in C. albicans, the molecular events driving synthase activation are currently undefined. In this study, using a combination of microbiologic and genetic techniques, we determined that the protein encoded by uncharacterized gene C1_01140C, and not the currently annotated C. albicans Gac1p, is the major regulatory subunit involved in glycogen synthesis. C1_01140Cp contains a conserved GVNK motif observed across multiple starch/glycogen-binding proteins in various species, and alanine substitution of each residue in this motif significantly impaired glycogen accumulation in C. albicans. Fluorescent protein tagging and microscopy indicated that C1_01140Cp-GFPy colocalized with CaGlc7p-tdTomato and CaGsy1p-tdTomato accordingly. Co-immunoprecipitation assays further confirmed that C1_01140Cp associates with CaGlc7p and CaGsy1p during glycogen synthesis. Lastly, c1_01140cΔ/Δ exhibited colonization defects in a murine model of vulvovaginal candidiasis. Collectively, our data indicate that uncharacterized C1_01140Cp is the functional ortholog of the PPP1R subunit ScGac1p in C. albicans.IMPORTANCEThe capacity to synthesize glycogen offers microbes metabolic flexibility, including the fungal pathogen Candida albicans. In Saccharomyces cerevisiae, dephosphorylation of glycogen synthase by the ScGlc7p-containing phosphatase is a critical rate-limiting step in glycogen synthesis. Subunits, including ScGac1p, target ScGlc7p to α-1,4-glucosyl primers for efficient ScGsy2p synthase activation. However, this process in C. albicans had not been delineated. Here, we show that the C. albicans genome encodes for two homologous phosphatase-binding subunits, annotated CaGac1p and uncharacterized C1_01140Cp, both containing a GVNK motif required for polysaccharide affinity. Surprisingly, loss of CaGac1p only moderately reduced glycogen accumulation, whereas loss of C1_01140Cp ablated it. Fluorescence microscopy and co-immunoprecipitation approaches revealed that C1_01140Cp associates with CaGlc7p and CaGsy1p during glycogen synthesis. Moreover, C1_01140Cp contributed to fungal fitness at the vaginal mucosa during murine vaginitis. Therefore, this work demonstrates that glycogen synthase regulation is conserved in C. albicans and C1_01140Cp is the functional ortholog of ScGac1p.

17.
J Med Chem ; 67(18): 15947-15967, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39250602

RESUMO

Pyridine nucleotide-disulfide oxidoreductases are underexplored as drug targets, and thioredoxin reductases (TrxRs) stand out as compelling pharmacological targets. Selective TrxR inhibition is challenging primarily due to the reliance on covalent inhibition strategies. Recent studies identified a regulatory and druggable pocket in Schistosoma mansoni thioredoxin glutathione reductase (TGR), a TrxR-like enzyme, and an established drug target for schistosomiasis. This site is termed the "doorstop pocket" because compounds that bind there impede the movement of an aromatic side-chain necessary for the entry and exit of NADPH and NADP+ during enzymatic turnover. This discovery spearheaded the development of new TGR inhibitors with efficacies surpassing those of current schistosomiasis treatment. Targeting the "doorstop pocket" is a promising strategy, as the pocket is present in all members of the pyridine nucleotide-disulfide oxidoreductase family, opening new avenues for exploring therapeutic approaches in diseases where the importance of these enzymes is established, including cancer and inflammatory and infectious diseases.


Assuntos
Inibidores Enzimáticos , Schistosoma mansoni , Tiorredoxina Dissulfeto Redutase , Tiorredoxina Dissulfeto Redutase/antagonistas & inibidores , Tiorredoxina Dissulfeto Redutase/metabolismo , Tiorredoxina Dissulfeto Redutase/química , Animais , Schistosoma mansoni/enzimologia , Humanos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , NADP/metabolismo , Complexos Multienzimáticos , NADH NADPH Oxirredutases
18.
Eur J Case Rep Intern Med ; 11(9): 004830, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39247239

RESUMO

Starvation ketoacidosis represents one of the three forms of metabolic acidosis caused by the accumulation of ketone bodies within the blood stream. It can be easily missed in patients who present acutely and are found to have an unexplained or profound metabolic acidosis. Here, we present a life-threatening case of severe ketoacidosis in a breast-feeding mother without diabetes who was on a strict ketogenic diet. Although a ketogenic diet has been previously considered to be safe in non-pregnant individuals, its safety in breast-feeding mothers in the post-partum period is less known and may be associated with greater harm. Health professionals and mothers should be aware of the potential risks associated with a strict ketogenic diet when combined with breast-feeding, especially in the earlier stages of the post-partum period. Prompt investigation, diagnosis and immediate management is vital to avoid life-threatening complications. We report a case admitted on the acute medical take with starvation ketoacidosis associated with ketogenic diet and adequate calorie consumption who was breast-feeding at the time of admission. LEARNING POINTS: Always check ketones in patients with an unexplained metabolic acidosis; there can be overlap between starvation, alcohol-related and lactic acidosis.Management of starvation ketoacidosis is often empirical, involving close monitoring of fluid status and electrolytes.Clinicians should discuss the risk of ketoacidosis associated with the ketogenic diet in women who plan to breast-feed and lose weight following pregnancy.

19.
Viruses ; 16(8)2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39205267

RESUMO

Obtaining a complete good-quality sequence and annotation for the long double-stranded DNA genome of the African swine fever virus (ASFV) from next-generation sequencing (NGS) technology has proven difficult, despite the increasing availability of reference genome sequences and the increasing affordability of NGS. A gap analysis conducted by the global African swine fever research alliance (GARA) partners identified that a standardized, automatic pipeline for NGS analysis was urgently needed, particularly for new outbreak strains. Whilst there are several diagnostic and research labs worldwide that collect isolates of the ASFV from outbreaks, many do not have the capability to analyze, annotate, and format NGS data from outbreaks for submission to NCBI, and some publicly available ASFV genomes have missing or incorrect annotations. We developed an automated, standardized pipeline for the analysis of NGS reads that directly provides users with assemblies and annotations formatted for their submission to NCBI. This pipeline is freely available on GitHub and has been tested through the GARA partners by examining two previously sequenced ASFV genomes; this study also aimed to assess the accuracy and limitations of two strategies present within the pipeline: reference-based (Illumina reads) and de novo assembly (Illumina and Nanopore reads) strategies.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Genoma Viral , Sequenciamento de Nucleotídeos em Larga Escala , Anotação de Sequência Molecular , Vírus da Febre Suína Africana/genética , Vírus da Febre Suína Africana/classificação , Vírus da Febre Suína Africana/isolamento & purificação , Animais , Suínos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Febre Suína Africana/virologia , Análise de Sequência de DNA/métodos , Biologia Computacional/métodos
20.
Sci Total Environ ; 951: 175414, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39127221

RESUMO

Worldwide, there is an increasing uptake of traffic management interventions aimed at reducing the impact of traffic related air pollution on public health. However, the evidence base linking the proposed changes with the resulting improvements in air quality is lacking. In this paper we present data from a micro-network of low-cost PM10 samplers collected from an isolated urban centre (Auckland, New Zealand). The data was then analysed using a new combination of analytical methods aimed to identify the composition and hence, the source of pollution. Whilst across the three sites mass concentration of PM10 and black carbon were similar, Raman spectroscopy successfully identified variations in the soot composition at different sites, enabling some particulate matter to be linked to diesel vehicle emissions. A mass reconstruction approach proved useful in determining that the airshed is well-mixed and also highlighted the impacts of urban design on recorded concentrations. The results show that networks of low-cost sensors, combined with the range of analytical techniques used here can help policymakers test the efficacy of interventions and management strategies designed to combat the burden of air pollution on public health.

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