RESUMEN
The enzyme 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) functions in the shikimate pathway which is responsible for the production of aromatic amino acids and precursors of other essential secondary metabolites in all plant species. EPSPS is also the molecular target of the herbicide glyphosate. While some plant EPSPS variants have been characterized with reduced glyphosate sensitivity and have been used in biotechnology, the glyphosate insensitivity typically comes with a cost to catalytic efficiency. Thus, there exists a need to generate additional EPSPS variants that maintain both high catalytic efficiency and high glyphosate tolerance. Here, we create a synthetic yeast system to rapidly study and evolve heterologous EPSP synthases for these dual traits. Using known EPSPS variants, we first validate that our synthetic yeast system is capable of recapitulating growth characteristics observed in plants grown in varying levels of glyphosate. Next, we demonstrate that variants from mutagenesis libraries with distinct phenotypic traits can be isolated depending on the selection criteria applied. By applying strong dual-trait selection pressure, we identify a notable EPSPS mutant after just a single round of evolution that displays robust glyphosate tolerance (Ki of nearly 1 mM) and improved enzymatic efficiency over the starting point (~2.5 fold). Finally, we show the crystal structure of corn EPSPS and the top resulting mutants and demonstrate that certain mutants have the potential to outperform previously reported glyphosate-resistant EPSPS mutants, such as T102I and P106S (denoted as TIPS), in whole-plant testing. Altogether, this platform helps explore the trade-off between glyphosate resistance and enzymatic efficiency.
Asunto(s)
3-Fosfoshikimato 1-Carboxiviniltransferasa , Glicina , Glifosato , Saccharomyces cerevisiae , 3-Fosfoshikimato 1-Carboxiviniltransferasa/genética , 3-Fosfoshikimato 1-Carboxiviniltransferasa/metabolismo , Glicina/análogos & derivados , Glicina/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Herbicidas/farmacología , Herbicidas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Resistencia a los Herbicidas/genéticaRESUMEN
ABSTRACT: It remains elusive how driver mutations, including those detected in circulating tumor DNA (ctDNA), affect prognosis in relapsed/refractory multiple myeloma (RRMM). Here, we performed targeted-capture sequencing using bone marrow plasma cells (BMPCs) and ctDNA of 261 RRMM cases uniformly treated with ixazomib, lenalidomide, and dexamethasone in a multicenter, prospective, observational study. We detected 24 and 47 recurrently mutated genes in BMPC and ctDNA, respectively. In addition to clonal hematopoiesis-associated mutations, varying proportion of driver mutations, particularly TP53 mutations (59.2% of mutated cases), were present in only ctDNA, suggesting their subclonal origin. In univariable analyses, ctDNA mutations of KRAS, TP53, DIS3, BRAF, NRAS, and ATM were associated with worse progression-free survival (PFS). BMPC mutations of TP53 and KRAS were associated with inferior PFS, whereas KRAS mutations were prognostically relevant only when detected in both BMPC and ctDNA. A total number of ctDNA mutations in the 6 relevant genes was a strong prognostic predictor (2-year PFS rates: 57.3%, 22.7%, and 0% for 0, 1, and ≥2 mutations, respectively) and independent of clinical factors and plasma DNA concentration. Using the number of ctDNA mutations, plasma DNA concentration, and clinical factors, we developed a prognostic index, classifying patients into 3 categories with 2-year PFS rates of 57.9%, 28.6%, and 0%. Serial analysis of ctDNA mutations in 94 cases revealed that TP53 and KRAS mutations frequently emerge after therapy. Thus, we clarify the genetic characteristics and clonal architecture of ctDNA mutations and demonstrate their superiority over BMPC mutations for prognostic prediction in RRMM. This study is a part of the C16042 study, which is registered at www.clinicaltrials.gov as #NCT03433001.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Compuestos de Boro , ADN Tumoral Circulante , Dexametasona , Glicina , Lenalidomida , Mieloma Múltiple , Humanos , Lenalidomida/administración & dosificación , Lenalidomida/uso terapéutico , Femenino , Glicina/análogos & derivados , Glicina/administración & dosificación , Glicina/uso terapéutico , Masculino , Anciano , Persona de Mediana Edad , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/genética , Mieloma Múltiple/mortalidad , Mieloma Múltiple/patología , Pronóstico , Dexametasona/administración & dosificación , ADN Tumoral Circulante/genética , ADN Tumoral Circulante/sangre , Compuestos de Boro/uso terapéutico , Compuestos de Boro/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Anciano de 80 o más Años , Mutación , Adulto , Estudios Prospectivos , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/patología , Biomarcadores de Tumor/genéticaRESUMEN
Magnetic fields are being used for detailed anatomical and functional examination of the human brain. In addition, evidence for their efficacy in treatment of brain dysfunctions is accumulating. Transcranial static magnetic field stimulation (tSMS) is a recently developed technique for noninvasively modifying brain functions. In tSMS, a strong and small magnet when placed over the skull can temporarily suppress brain functions. Its modulatory effects persist beyond the time of stimulation. However, the neurophysiological mechanisms underlying tSMS-induced plasticity remain unclear. Here, using acute motor cortical slice preparation obtained from male C57BL/6N mice, we show that tSMS alters the intrinsic electrical properties of neurons by altering the activity of chloride (Cl-) channels in neurons. Exposure of mouse pyramidal neurons to a static magnetic field (SMF) at a strength similar to human tSMS temporarily decreased their excitability and induced transient neuronal swelling. The effects of SMF were blocked by DIDS and GlyH-101, but not by NPPB, consistent with the pharmacological profile of SLC26A11, a transporter protein with Cl- channel activity. Whole-cell voltage-clamp recordings of the GlyH-101-sensitive Cl- current component showed significant enhancement of the component at both subthreshold and depolarized membrane potentials after SMF application, resulting in shunting inhibition and reduced repetitive action potential (AP) firing at the respective potentials. Thus, this study provides the first neurophysiological evidence for the inhibitory effect of tSMS on neuronal activity and advances our mechanistic understanding of noninvasive human neuromodulation.
Asunto(s)
Cloruros , Glicina/análogos & derivados , Hidrazinas , Campos Magnéticos , Masculino , Humanos , Animales , Ratones , Ratones Endogámicos C57BL , Estimulación Magnética Transcraneal/métodosRESUMEN
The hypoxia response pathway enables adaptation to oxygen deprivation. It is mediated by hypoxia-inducible factors (HIF), which promote metabolic reprogramming, erythropoiesis, angiogenesis and tissue remodeling. This led to the successful development of HIF-inducing drugs for treating anemia and some of these molecules are now in clinic. However, elevated levels of HIFs are frequently associated with tumor growth, poor prognosis, and drug resistance in various cancers, including hepatocellular carcinoma (HCC). Consequently, there are concerns regarding the recommendation of HIF-inducing drugs in certain clinical situations. Here, we analyzed the effects of two HIF-inducing drugs, Molidustat and Roxadustat, in the well-characterized HCC cell line Huh7. These drugs increased HIF-1α and HIF-2α protein levels which both participate in inducing hypoxia response genes such as BNIP3, SERPINE1, LDHA or EPO. Combined transcriptomics, proteomics and metabolomics showed that Molidustat increased the expression of glycolytic enzymes, while the mitochondrial network was fragmented and cellular respiration decreased. This metabolic remodeling was associated with a reduced proliferation and a lower demand for pyrimidine supply, but an increased ability of cells to convert pyruvate to lactate. This was accompanied by a higher resistance to the inhibition of mitochondrial respiration by antimycin A, a phenotype confirmed in Roxadustat-treated Huh7 cells and Molidustat-treated hepatoblastoma cells (Huh6 and HepG2). Overall, this study shows that HIF-inducing drugs increase the metabolic resilience of liver cancer cells to metabolic stressors, arguing for careful monitoring of patients treated with HIF-inducing drugs, especially when they are at risk of liver cancer.
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Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Carcinoma Hepatocelular , Proliferación Celular , Subunidad alfa del Factor 1 Inducible por Hipoxia , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Proliferación Celular/efectos de los fármacos , Línea Celular Tumoral , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Isoquinolinas/farmacología , Glicina/análogos & derivados , Glicina/farmacología , Estrés Fisiológico/efectos de los fármacos , Hipoxia de la Célula/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacosRESUMEN
Childhood melanoma is a rare and biologically heterogeneous pediatric malignancy. The differential diagnosis of pediatric melanoma is usually broad, including a wide variety of spindle cell or epithelioid neoplasms. Different molecular alterations affecting the MAPK and PI3K/AKT/mTOR pathways, tumor suppressor genes, and telomerase reactivation have been implicated in melanoma tumorigenesis and progression. Here, we report a novel MED15::ATF1 fusion in a pediatric melanoma with spitzoid features and an aggressive clinical course.
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Glicina , Melanoma , Nevo de Células Epitelioides y Fusiformes , Proteínas de Fusión Oncogénica , Pirroles , Neoplasias Cutáneas , Niño , Humanos , Diagnóstico Diferencial , Glicina/análogos & derivados , Complejo Mediador , Melanoma/diagnóstico , Melanoma/genética , Melanoma/patología , Nevo de Células Epitelioides y Fusiformes/diagnóstico , Fosfatidilinositol 3-Quinasas , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología , Proteínas de Fusión Oncogénica/genéticaRESUMEN
Ionising radiation exposure can lead to acute haematopoietic radiation syndrome. Despite significant advancements in the field of radioprotection, no drugs with high efficacy and low toxicity have yet been approved by the Food and Drug Administration. FG-4592, as a proline hydroxylase inhibitor, may play an important role in radioprotection of the haematopoietic system. Mice were peritoneal injected with FG-4592 or normal saline. After irradiation, the survival time, body weight, peripheral blood cell and bone marrow cell (BMC) count, cell apoptosis, pathology were analysed and RNA-sequence technique (RNA-Seq) was conducted to explore the mechanism of FG-4592 in the haematopoietic system. Our results indicated that FG-4592 improved the survival rate and weight of irradiated mice and protected the spleen, thymus and bone marrow from IR-induced injury. The number of BMCs was increased and protected against IR-induced apoptosis. FG-4592 also promoted the recovery of the blood system and erythroid differentiation. The results of RNA-Seq and Western blot showed that the NF-κB signalling pathway and hypoxia-inducible factor-1 (HIF-1) signalling pathway were upregulated by FG-4592. Meanwhile, RT-PCR results showed that FG-4592 could promote inflammatory response significantly. FG-4592 exhibited radioprotective effects in the haematopoietic system by promoting inflammatory response and targeting the NF-κB, HIF signalling pathway.
Asunto(s)
Apoptosis , Radiación Ionizante , Protectores contra Radiación , Animales , Ratones , Protectores contra Radiación/farmacología , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Transducción de Señal/efectos de los fármacos , FN-kappa B/metabolismo , Masculino , Ratones Endogámicos C57BL , Sistema Hematopoyético/efectos de los fármacos , Sistema Hematopoyético/efectos de la radiación , Síndrome de Radiación Aguda/prevención & control , Síndrome de Radiación Aguda/tratamiento farmacológico , Hematopoyesis/efectos de los fármacos , Hematopoyesis/efectos de la radiación , Traumatismos Experimentales por Radiación/prevención & control , Traumatismos Experimentales por Radiación/metabolismo , Irradiación Corporal Total , Glicina/análogos & derivados , IsoquinolinasRESUMEN
a-Tertiary amino acids are essential components of drugs and agrochemicals, yet traditional syntheses are step-intensive and provide access to a limited range of structures with varying levels of enantioselectivity. Here, we report the α-alkylation of unprotected alanine and glycine by pyridinium salts using pyridoxal (PLP)-dependent threonine aldolases with a Rose Bengal photoredox catalyst. The strategy efficiently prepares various a-tertiary amino acids in a single chemical step as a single enantiomer. UV-vis spectroscopy studies reveal a ternary interaction between the pyridinium salt, protein, and photocatalyst, which we hypothesize is responsible for localizing radical formation to the active site. This method highlights the opportunity for combining photoredox catalysts with enzymes to reveal new catalytic functions for known enzymes.
Asunto(s)
Aminoácidos , Aminoácidos/química , Glicina Hidroximetiltransferasa/metabolismo , Glicina Hidroximetiltransferasa/química , Procesos Fotoquímicos , Biocatálisis , Catálisis , Alquilación , Glicina/química , Glicina/análogos & derivados , Estereoisomerismo , Estructura Molecular , Oxidación-ReducciónRESUMEN
BACKGROUND: Ivosidenib is primarily metabolized by CYP3A4; however, it induces CYP450 isozymes, including CYP3A4 and CYP2C9, whereas it inhibits drug transporters, including P-glycoprotein. Patients with acute myeloid leukemia are at risk of invasive fungal infections, and therefore posaconazole and voriconazole are commonly used in this population. Voriconazole is a substrate of CYP2C9, CYP2C19, and CYP3A4; therefore, concomitant ivosidenib may result in decreased serum concentrations. Although posaconazole is a substrate of P-glycoprotein, it is metabolized primarily via UDP glucuronidation; thus, the impact of ivosidenib on posaconazole exposure is unknown. METHODS: Patients treated with ivosidenib and concomitant triazole with at least one serum trough level were included. Subtherapeutic levels were defined as posaconazole <700 ng/mL and voriconazole <1.0 µg/mL. The incidences of breakthrough invasive fungal infections and QTc prolongation were identified at least 5 days after initiation of ivosidenib with concomitant triazole. RESULTS: Seventy-eight serum triazole levels from 31 patients receiving ivosidenib-containing therapy and concomitant triazole were evaluated. Of the 78 concomitant levels, 47 (60%) were subtherapeutic (posaconazole: n = 20 of 43 [47%]; voriconazole: n = 27 of 35 [77%]). Compared to levels drawn while patients were off ivosidenib, median triazole serum levels during concomitant ivosidenib were significantly reduced. There was no apparent increase in incidence of grade 3 QTc prolongation with concomitant azole antifungal and ivosidenib 500 mg daily. CONCLUSIONS: This study demonstrated that concomitant ivosidenib significantly reduced posaconazole and voriconazole levels. Voriconazole should be avoided, empiric high-dose posaconazole (>300 mg/day) may be considered, and therapeutic drug monitoring is recommended in all patients receiving concomitant ivosidenib.
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Glicina , Leucemia Mieloide Aguda , Síndromes Mielodisplásicos , Piridinas , Triazoles , Humanos , Leucemia Mieloide Aguda/tratamiento farmacológico , Triazoles/administración & dosificación , Triazoles/uso terapéutico , Triazoles/farmacocinética , Masculino , Femenino , Persona de Mediana Edad , Anciano , Síndromes Mielodisplásicos/tratamiento farmacológico , Piridinas/administración & dosificación , Piridinas/uso terapéutico , Piridinas/farmacocinética , Glicina/análogos & derivados , Glicina/uso terapéutico , Glicina/administración & dosificación , Voriconazol/uso terapéutico , Voriconazol/administración & dosificación , Anciano de 80 o más Años , Interacciones Farmacológicas , Adulto , Antifúngicos/administración & dosificación , Antifúngicos/uso terapéutico , Antineoplásicos/efectos adversosRESUMEN
This phase II study evaluated time-limited (24 cycles) treatment with ibrutinib and ixazomib in newly diagnosed (NDWM; n = 9) and relapsed/refractory (RRWM; n = 12) Waldenström macroglobulinaemia (WM). The overall response rate (ORR) was 76.2% (n = 16) in 21 evaluable patients with no patient achieving a complete response (CR). The median duration of treatment was 15.6 months, and after a median follow-up time of 25.7 months, the median progression-free survival (PFS) was 22.9 months. While the primary end-point was not met (CR rate at any time) and 28.5% discontinued treatment due to toxicity, ibrutinib plus ixazomib led to a clinically meaningful ORR and PFS. Combined Bruton's tyrosine kinase (BTK) and proteasome inhibition merits further evaluation in WM.
Asunto(s)
Adenina , Protocolos de Quimioterapia Combinada Antineoplásica , Compuestos de Boro , Glicina , Piperidinas , Macroglobulinemia de Waldenström , Humanos , Compuestos de Boro/uso terapéutico , Compuestos de Boro/administración & dosificación , Compuestos de Boro/efectos adversos , Macroglobulinemia de Waldenström/tratamiento farmacológico , Glicina/análogos & derivados , Glicina/administración & dosificación , Glicina/efectos adversos , Glicina/uso terapéutico , Adenina/análogos & derivados , Masculino , Anciano , Persona de Mediana Edad , Femenino , Piperidinas/uso terapéutico , Piperidinas/administración & dosificación , Piperidinas/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Anciano de 80 o más Años , Pirimidinas/efectos adversos , Pirimidinas/uso terapéutico , Pirimidinas/administración & dosificación , Pirazoles/uso terapéutico , Pirazoles/efectos adversos , Pirazoles/administración & dosificación , Adulto , Resultado del TratamientoRESUMEN
This open-label, prospective trial evaluated the combination of ixazomib, cyclophosphamide and dexamethasone (ICD) in 12 newly diagnosed POEMS syndrome patients. The study is registered with the Chinese Clinical Trials Registry (ChiCTR2000030072). The treatment protocol consisted of 12 cycles of the ICD regimen compromising ixazomib (4 mg on Days 1, 8 and 15), oral cyclophosphamide (300 mg on Days 1, 8 and 15) and dexamethasone (20 mg weekly). A total of 12 patients received a median of 10 (range: 3-23) cycles of the ICD regimen. The haematological response could be evaluated in 10 patients. The overall haematological response rate was 80% (8/10), with 30% (3/10) achieving complete haematological response, and the overall serum VEGF response rate and neurological response were 100% and 83.3% respectively. Two patients experienced grade 3/4 AEs, including diarrhoea (n = 1) and leukopenia (n = 1). The combination of ixazomib, cyclophosphamide and dexamethasone demonstrated both efficacy and safety in newly diagnosed POEMS syndrome, making it a viable treatment option.
Asunto(s)
Compuestos de Boro , Ciclofosfamida , Dexametasona , Glicina , Síndrome POEMS , Humanos , Ciclofosfamida/administración & dosificación , Ciclofosfamida/efectos adversos , Ciclofosfamida/uso terapéutico , Compuestos de Boro/administración & dosificación , Compuestos de Boro/efectos adversos , Compuestos de Boro/uso terapéutico , Dexametasona/administración & dosificación , Dexametasona/efectos adversos , Dexametasona/uso terapéutico , Glicina/análogos & derivados , Glicina/administración & dosificación , Glicina/efectos adversos , Glicina/uso terapéutico , Síndrome POEMS/tratamiento farmacológico , Síndrome POEMS/diagnóstico , Síndrome POEMS/sangre , Persona de Mediana Edad , Femenino , Masculino , Adulto , Estudios Prospectivos , Anciano , Resultado del Tratamiento , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificaciónRESUMEN
The role of the proteasome inhibitor ixazomib in the treatment of POEMS syndrome continues to evolve. He and colleagues present the results of a study investigating ixazomib in combination with cyclophosphamide and dexamethasone in newly diagnosed POEMS patients. The triplet showed excellent efficacy and tolerability, and constitutes an effective treatment option for patients with POEMS. Commentary on: He et al. An open-label, prospective trial to evaluate the efficacy and safety of ixazomib in combination with cyclophosphamide and dexamethasone in patients with newly-diagnosed POEMS syndrome. Br J Haematol 2024;205:478-482.
Asunto(s)
Compuestos de Boro , Dexametasona , Glicina , Síndrome POEMS , Compuestos de Boro/uso terapéutico , Compuestos de Boro/administración & dosificación , Compuestos de Boro/efectos adversos , Humanos , Síndrome POEMS/tratamiento farmacológico , Síndrome POEMS/diagnóstico , Glicina/análogos & derivados , Glicina/uso terapéutico , Glicina/administración & dosificación , Glicina/efectos adversos , Dexametasona/uso terapéutico , Dexametasona/administración & dosificación , Dexametasona/efectos adversos , Ciclofosfamida/uso terapéutico , Ciclofosfamida/administración & dosificación , Ciclofosfamida/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversosRESUMEN
Quantum mechanical calculations are used to explore the thermodynamics of possible prebiotic synthesis of the building blocks of nucleic acids. Different combinations of D-ribofuranose (Ribf) and N-(2-aminoethyl)-glycine (AEG) (trifunctional connectors (TCs)); the nature of the Ribf, its anomeric form, and its ring puckering (conformation); and the nature of the nucleobases (recognition units (RUs)) are considered. The combinatorial explosion of possible nucleosides has been drastically reduced on physicochemical grounds followed by a detailed thermodynamic evaluation of alternative synthetic pathways. The synthesis of nucleosides containing N-(2-aminoethyl)-glycine (AEG) is predicted to be thermodynamically favored suggesting a possible role of AEG as a component of an ancestral proto-RNA that may have preceded today's nucleic acids. A new pathway for the building of free nucleotides (exemplified by 5'-uridine monophosphate (UMP)) and of AEG dipeptides is proposed. This new pathway leads to a spontaneous formation of free UMP assisted by an AEG nucleoside in an aqueous environment. This appears to be a workaround to the "water problem" that prohibits the synthesis of nucleotides in water.
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Glicina , ARN , Termodinámica , ARN/química , Glicina/análogos & derivados , Glicina/química , Origen de la Vida , Evolución Química , NucleósidosRESUMEN
The effect of immunoinflammation on bone repair during the recovery process of bone defects needs to be further explored. It is reported that Mg2+ can promote bone repair with immunoregulatory effect, but the underlying mechanism on adaptive immunity is still unclear. Here, by using chitosan and hyaluronic acid-coated Mg2+ (CSHA-Mg) in bone-deficient mice, it is shown that Mg2+ can inhibit the activation of CD4+ T cells and increase regulatory T cell formation by inducing immunosuppressive dendritic cells (imDCs). Mechanistically, Mg2+ initiates the activation of the MAPK signaling pathway through TRPM7 channels on DCs. This process subsequently induces the downstream HIF-1α expression, a transcription factor that amplifies TGF-ß production and inhibits the effective T cell function. In vivo, knock-out of HIF-1α in DCs or using a HIF-1α inhibitor PX-478 reverses inhibition of bone inflammation and repair promotion upon Mg2+-treatment. Moreover, roxadustat, which stabilizes HIF-1α protein expression, can significantly promote immunosuppression and bone repair in synergism with CSHA-Mg. Thus, the findings identify a key mechanism for DCs and its HIF-1α-TGF-ß axis in the induction of immunosuppressive bone microenvironment, providing potential targets for bone regeneration.
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Células Dendríticas , Subunidad alfa del Factor 1 Inducible por Hipoxia , Magnesio , Factor de Crecimiento Transformador beta , Animales , Células Dendríticas/efectos de los fármacos , Células Dendríticas/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Magnesio/farmacología , Ratones , Ratones Endogámicos C57BL , Microambiente Celular/efectos de los fármacos , Huesos/efectos de los fármacos , Huesos/metabolismo , Regeneración Ósea/efectos de los fármacos , Isoquinolinas/farmacología , Glicina/análogos & derivados , Glicina/farmacología , Canales Catiónicos TRPM/metabolismo , Transducción de Señal/efectos de los fármacos , Quitosano/farmacología , Quitosano/química , Compuestos de Mostaza , FenilpropionatosRESUMEN
Biofilm formation is a common adaptation enabling bacteria to thrive in various environments and withstand external pressures. In the context of host-microbe interactions, biofilms play vital roles in establishing microbiomes associated with animals and plants and are used by opportunistic microbes to facilitate survival within hosts. Investigating biofilm dynamics, composition, and responses to environmental stressors is crucial for understanding microbial community assembly and biofilm regulation in health and disease. In this study, we explore in vivo colonization and in vitro biofilm formation abilities of core members of the honey bee (Apis mellifera) gut microbiota. Additionally, we assess the impact of glyphosate, a widely used herbicide with antimicrobial properties, and a glyphosate-based herbicide formulation on growth and biofilm formation in bee gut symbionts as well as in other biofilm-forming bacteria associated with diverse animals and plants. Our results demonstrate that several strains of core bee gut bacterial species can colonize the bee gut, which probably depends on their ability to form biofilms. Furthermore, glyphosate exposure elicits variable effects on bacterial growth and biofilm formation. In some instances, the effects correlate with the bacteria's ability to encode a susceptible or tolerant version of the enzyme inhibited by glyphosate in the shikimate pathway. However, in other instances, no such correlation is observed. Testing the herbicide formulation further complicates comparisons, as results often diverge from glyphosate exposure alone, suggesting that co-formulants influence bacterial growth and biofilm formation. These findings highlight the nuanced impacts of environmental stressors on microbial biofilms, with both ecological and host health-related implications. IMPORTANCE: Biofilms are essential for microbial communities to establish and thrive in diverse environments. In the honey bee gut, the core microbiota member Snodgrassella alvi forms biofilms, potentially aiding the establishment of other members and promoting interactions with the host. In this study, we show that specific strains of other core members, including Bifidobacterium, Bombilactobacillus, Gilliamella, and Lactobacillus, also form biofilms in vitro. We then examine the impact of glyphosate, a widely used herbicide that can disrupt the bee microbiota, on bacterial growth and biofilm formation. Our findings demonstrate the diverse effects of glyphosate on biofilm formation, ranging from inhibition to enhancement, reflecting observations in other beneficial or pathogenic bacteria associated with animals and plants. Thus, glyphosate exposure may influence bacterial growth and biofilm formation, potentially shaping microbial establishment on host surfaces and impacting health outcomes.
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Bacterias , Biopelículas , Microbioma Gastrointestinal , Glicina , Glifosato , Herbicidas , Simbiosis , Animales , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Abejas/microbiología , Glicina/análogos & derivados , Glicina/farmacología , Microbioma Gastrointestinal/efectos de los fármacos , Herbicidas/farmacología , Bacterias/efectos de los fármacos , Bacterias/crecimiento & desarrollo , Fenómenos Fisiológicos Bacterianos/efectos de los fármacosRESUMEN
TOURMALINE-MM1, the only blinded randomized study in patients with relapsed and/or refractory multiple myeloma (RRMM; ≥1 prior therapy) in the last 10 years, investigated ixazomib + lenalidomide + dexamethasone (IRd) versus lenalidomide + dexamethasone (Rd). Final overall survival (OS) data were based on a median follow-up of 85 months. In RRMM trials where patients have had 1-3 relapses after initial treatment, a high proportion receive subsequent therapy. Application of salvage therapies in blinded trials and newer modes of therapy can increasingly complicate the interpretation of OS. This analysis explores the impact of subsequent therapies on OS outcomes in TOURMALINE-MM1. The inverse probability of censoring weights (IPCW) method, marginal structural model (MSM), and rank-preserving structural failure time model (RPSFTM) were utilized to adjust for confounding on OS, introduced by subsequent therapies. Analyses were conducted for the intent-totreat (ITT) population and ≥2 prior lines subgroup. Unadjusted hazard ratio (HR) for IRd versus Rd was 0.94 (95% confidence interval [CI]: 0.78-1.13) in the ITT population. After adjusting for the impact of subsequent therapies by the RPSFTM method, estimated HR for IRd versus Rd in the ITT population was 0.89 (95% CI: 0.74-1.07). Adjusting with IPCW and MSM methods also showed an improvement in HR, favoring IRd. IRd may be particularly beneficial in patients with ≥2 prior lines of therapy (IPCW and MSM HR=0.52, 95% CI: 0.30-0.88; RPSFTM HR=0.68, 95% CI: 0.51-0.91). These analyses highlight the growing challenge of demonstrating OS benefit in MM patients and the importance of assessing confounding introduced by subsequent therapies when interpreting OS.
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Protocolos de Quimioterapia Combinada Antineoplásica , Compuestos de Boro , Dexametasona , Glicina , Lenalidomida , Mieloma Múltiple , Humanos , Glicina/análogos & derivados , Glicina/uso terapéutico , Glicina/administración & dosificación , Lenalidomida/administración & dosificación , Lenalidomida/uso terapéutico , Dexametasona/administración & dosificación , Dexametasona/uso terapéutico , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/mortalidad , Compuestos de Boro/administración & dosificación , Compuestos de Boro/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Femenino , Masculino , Anciano , Persona de Mediana Edad , Resultado del TratamientoRESUMEN
PURPOSE: ß cell mass (BCM) and function are essential to the diagnosis and therapy of diabetes. Diabetic patients serve ß cell loss is, and damage of ß cells leads to severe insulin deficiency. Our understanding of the role of BCM in diabetes progression is extremely limited by lacking efficient methods to evaluate BCM in vivo. In vitro methods of labeling islets, including loading of contrast reagent or integration of exogenous biomarker, require artificial manipulation on islets, of which the clinical application is limited. Imaging methods targeting endogenous biomarkers may solve the above problems. However, traditional reagents targeting GLP-1R and VAMT2 result in a high background of adjacent tissues, complicating the identification of pancreatic signals. Here, we report a non-invasive and quantitative imaging technique by using radiolabeled glycine mimics ([18F]FBG, a boron-trifluoride derivative of glycine) to assay islet function and monitor BCM changes in living animals. METHODS: Glycine derivatives, FBG, FBSa, 2Me-FBG, 3Me-FBG, were successfully synthesized and labeled with 18F. Specificity of glycine derivatives were characterized by in vitro experiment. PET imaging and biodistribution studies were performed in animal models carring GLYT over-expressed cells. In vivo evaluation of BCM with [18F]FBG were performed in STZ (streptozocin) induced T1D (type 1 diabetes) models. RESULTS: GLYT responds to excess blood glycine levels and transports glycine into islet cells to maintain the activity of the glycine receptor (GLYR). Best PET imaging condition was 80 min after given a total of 240 ~ 250 nmol imaging reagent (a mixture of [18F]FBG and natural glycine) intravenously. [18F]FBG can detect both endogenous and exogenous islets clearly in vivo. When applied to STZ induced T1D mouse models, total uptake of [18F]FBG in the pancreas exhibited a linear correlation with survival BCM. CONCLUSION: [18F]FBG targeting the endogenous glycine transporter (GLYT), which is highly expressed on islet cells, avoiding extra modification on islet cells. Meanwhile the highly restricted expression pattern of GLYT excluded the background in adjacent tissues. This [18F]FBG-based imaging technique provides a non-invasive method to quantify BCM in vivo, implying a new evaluation index for diabetic assessment.
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Glicina , Células Secretoras de Insulina , Animales , Células Secretoras de Insulina/metabolismo , Ratones , Glicina/análogos & derivados , Distribución Tisular , Biomarcadores/metabolismo , Tomografía de Emisión de Positrones/métodos , Masculino , Radioisótopos de Flúor , Humanos , Compuestos de Boro/química , Diabetes Mellitus Experimental/diagnóstico por imagen , Diabetes Mellitus Experimental/metabolismoRESUMEN
BACKGROUND: Creatine plays a significant role in energy metabolism and positively impacts anaerobic energy capacity, muscle mass, and physical performance. Endogenous creatine synthesis requires guanidinoacetic acid (GAA) and methionine. GAA can be an alternative to creatine supplements and has been tested as a beneficial feed additive in the animal industry. When pigs are fed GAA with excess methionine, creatine is synthesized without feedback regulation. In contrast, when dietary methionine is limited, creatine synthesis is limited, yet, GAA does not accumulate in plasma, urine, or liver. OBJECTIVE: We hypothesized that portal GAA appearance requires adequate dietary methionine. METHODS: Yucatan miniature piglets (17-21 d old; n = 20) were given a 4 h duodenal infusion of complete elemental diets with supplemental GAA plus 1 of 4 methionine concentrations representing either 20%, 80%, 140%, or 200% of the dietary methionine requirement. Arterial and portal blood metabolites were measured along with blood flow to determine mass balance across the gut. [3H-methyl] methionine was infused to measure the methionine incorporation rate into creatine. RESULTS: GAA balance across the gut was highest in the 200% methionine group, indicating excess dietary methionine enhanced GAA absorption. Creatine synthesis in the liver and jejunum was higher with higher concentrations of methionine, emphasizing that the transmethylation of GAA to creatine depends on sufficient dietary methionine. Hepatic GAA concentration was higher in the 20% methionine group, suggesting low dietary methionine limited GAA conversion to creatine, which led to GAA accumulation in the liver. CONCLUSIONS: GAA absorption and conversion to creatine require a sufficient amount of methionine, and the supplementation strategies should accommodate this interaction.
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Creatina , Dieta , Glicina , Metionina , Porcinos Enanos , Animales , Metionina/administración & dosificación , Metionina/metabolismo , Glicina/análogos & derivados , Glicina/administración & dosificación , Glicina/metabolismo , Porcinos , Alimentación Animal/análisis , Suplementos Dietéticos , Hígado/metabolismo , Masculino , FemeninoRESUMEN
BACKGROUND: International guidelines recommend ivosidenib followed by modified FOLFOX (mFOLFOX) for advanced intrahepatic cholangiocarcinoma (ICC) with isocitrate dehydrogenase 1 (IDH1) mutations. Taiwan National Health Insurance covers only fluorouracil/leucovorin (5-FU/LV) chemotherapy for this ICC group, and there has been no prior economic evaluation of ivosidenib. Therefore, we aimed to assess ivosidenib's cost-effectiveness in previously treated, advanced ICC-presenting IDH1 mutations compared with mFOLFOX or 5-FU/LV. METHODS: A 3-state partitioned survival model was employed to assess ivosidenib's cost-effectiveness over a 10-year horizon with a 3% discount rate, setting the willingness-to-pay threshold at 3 times the 2022 GDP per capita. Efficacy data for Ivosidenib, mFOLFOX, and 5-FU/LV were sourced from the ClarIDHy, ABC06, and NIFTY trials, respectively. Ivosidenib's cost was assumed to be NT$10,402/500 mg. Primary outcomes included incremental cost-effectiveness ratios (ICERs) and net monetary benefit. Deterministic sensitivity analyses (DSA) and probabilistic sensitivity analyses (PSA) were employed to evaluate uncertainty and explore price reduction scenarios. RESULTS: Ivosidenib exhibited ICERs of NT$6,268,528 and NT$5,670,555 compared with mFOLFOX and 5-FU/LV, respectively, both exceeding the established threshold. PSA revealed that ivosidenib was unlikely to be cost-effective, except when it was reduced to NT$4,161 and NT$5,201/500 mg when compared with mFOLFOX and 5-FU/LV, respectively. DSA underscored the significant influence of ivosidenib's cost and utility values on estimate uncertainty. CONCLUSIONS: At NT$10,402/500 mg, ivosidenib was not cost-effective for IDH1-mutant ICC patients compared with mFOLFOX or 5-FU/LV, indicating that a 50-60% price reduction is necessary for ivosidenib to be cost-effective in this patient group.
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Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias de los Conductos Biliares , Colangiocarcinoma , Análisis Costo-Beneficio , Fluorouracilo , Glicina , Isocitrato Deshidrogenasa , Leucovorina , Mutación , Piridinas , Humanos , Isocitrato Deshidrogenasa/genética , Colangiocarcinoma/tratamiento farmacológico , Colangiocarcinoma/genética , Piridinas/uso terapéutico , Piridinas/economía , Taiwán , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/economía , Fluorouracilo/uso terapéutico , Fluorouracilo/economía , Glicina/análogos & derivados , Glicina/uso terapéutico , Glicina/economía , Neoplasias de los Conductos Biliares/tratamiento farmacológico , Neoplasias de los Conductos Biliares/genética , Neoplasias de los Conductos Biliares/economía , Leucovorina/uso terapéutico , Leucovorina/economía , Masculino , Femenino , Compuestos Organoplatinos/uso terapéutico , Compuestos Organoplatinos/economía , Persona de Mediana EdadRESUMEN
Some aplastic anemia(AA) patients only have partial hematological responses after immunosuppressive therapy. Failure to achieve complete normalization of blood counts, particularly hemoglobin, will reduce their quality of life. This open-label pilot study was conducted to evaluate the efficacy and safety of roxadustat in this setting. A total of 14 patients with AA who had inadequate erythroid response after immunosuppressive therapy were included in the study. The primary efficacy endpoint was hemoglobin response at week 8 after roxadustat treatment. The median duration of roxadustat therapy was 14 (4-30) weeks, with 12 patients receiving roxadustat for ≥ 8 weeks. At week 8, nine patients (9/14, 64.3%) had their hemoglobin rising for at least 15 g/L, with two patients (2/14, 14.3%) achieving normal hemoglobin levels. By the last follow-up, hemoglobin responses were observed in 10 patients (10/14, 71.4%), with 4 patients(4/14, 28.6%) having normal hemoglobin levels. Roxadustat was tapered or discontinued in four responded patients; one relapsed after 12 weeks of tapering, and three maintained their response. Four patients (4/14, 28.6%) experienced mild adverse effects during therapy. Roxadustat is safe and well tolerated by patients with AA. Treatment with the hypoxia-inducible factor prolyl hydroxylase inhibitor improves hemoglobin levels in AA patients with inadequate erythroid responses.
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Anemia Aplásica , Glicina , Isoquinolinas , Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Proyectos Piloto , Isoquinolinas/uso terapéutico , Isoquinolinas/efectos adversos , Isoquinolinas/administración & dosificación , Anemia Aplásica/tratamiento farmacológico , Anemia Aplásica/sangre , Glicina/análogos & derivados , Glicina/uso terapéutico , Glicina/efectos adversos , Anciano , Hemoglobinas/análisis , Resultado del Tratamiento , Adulto Joven , Datos Preliminares , AdolescenteRESUMEN
Creatine is a natural nitrogenous organic acid that is integral to energy metabolism and crucial for proper cell functioning. The kidneys are involved in the first step of creatine production. With kidney transplantation being the gold-standard treatment for end-stage kidney disease, kidney transplant recipients (KTR) may be at risk of impaired creatine synthesis. We aimed to compare creatine homeostasis between KTR and controls. Plasma and urine concentrations of arginine, glycine, guanidinoacetate, creatine and creatinine were measured in 553 KTR and 168 healthy controls. Creatine intake was assessed using food frequency questionnaires. Iothalamate-measured GFR data were available in subsets of 157 KTR and 167 controls. KTR and controls had comparable body weight, height and creatine intake (all P > 0.05). However, the total creatine pool was 14% lower in KTR as compared to controls (651 ± 178 vs. 753 ± 239 mmol, P < 0.001). The endogenous creatine synthesis rate was 22% lower in KTR as compared to controls (7.8 ± 3.0 vs. 10.0 ± 4.1 mmol per day, P < 0.001). Despite lower GFR, the plasma guanidinoacetate and creatine concentrations were 21% and 41% lower in KTR as compared to controls (both P < 0.001). Urinary excretion of guanidinoacetate and creatine were 66% and 59% lower in KTR as compared to controls (both P < 0.001). In KTR, but not in controls, a higher measured GFR was associated with a higher endogenous creatine synthesis rate (std. beta: 0.21, 95% CI: 0.08; 0.33; P = 0.002), as well as a higher total creatine pool (std. beta: 0.22, 95% CI: 0.11; 0.33; P < 0.001). These associations were fully mediated (93% and 95%; P < 0.001) by urinary guanidinoacetate excretion which is consistent with production of the creatine precursor guanidinoacetate as rate-limiting factor. Our findings highlight that KTR have a disturbed creatine homeostasis as compared to controls. Given the direct relationship of measured GFR with endogenous creatine synthesis rate and the total creatine pool, creatine supplementation might be beneficial in KTR with low kidney function.Trial registration ID: NCT02811835.Trial registration URL: https://clinicaltrials.gov/ct2/show/NCT02811835 .