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1.
Mol Cell ; 81(9): 1905-1919.e12, 2021 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-33852893

RESUMEN

Oxidative phosphorylation (OXPHOS) and glycolysis are the two major pathways for ATP production. The reliance on each varies across tissues and cell states, and can influence susceptibility to disease. At present, the full set of molecular mechanisms governing the relative expression and balance of these two pathways is unknown. Here, we focus on genes whose loss leads to an increase in OXPHOS activity. Unexpectedly, this class of genes is enriched for components of the pre-mRNA splicing machinery, in particular for subunits of the U1 snRNP. Among them, we show that LUC7L2 represses OXPHOS and promotes glycolysis by multiple mechanisms, including (1) splicing of the glycolytic enzyme PFKM to suppress glycogen synthesis, (2) splicing of the cystine/glutamate antiporter SLC7A11 (xCT) to suppress glutamate oxidation, and (3) secondary repression of mitochondrial respiratory supercomplex formation. Our results connect LUC7L2 expression and, more generally, the U1 snRNP to cellular energy metabolism.


Asunto(s)
Glucólisis , Fosforilación Oxidativa , Precursores del ARN/metabolismo , Empalme del ARN , ARN Mensajero/metabolismo , Proteínas de Unión al ARN/metabolismo , Ribonucleoproteína Nuclear Pequeña U1/metabolismo , Sistema de Transporte de Aminoácidos y+/genética , Sistema de Transporte de Aminoácidos y+/metabolismo , Proteínas del Complejo de Cadena de Transporte de Electrón/genética , Proteínas del Complejo de Cadena de Transporte de Electrón/metabolismo , Regulación de la Expresión Génica , Estudio de Asociación del Genoma Completo , Ácido Glutámico/metabolismo , Glucógeno/metabolismo , Glucólisis/genética , Células HEK293 , Células HeLa , Humanos , Células K562 , Mitocondrias/genética , Mitocondrias/metabolismo , Oxidación-Reducción , Fosfofructoquinasa-1 Tipo Muscular/genética , Fosfofructoquinasa-1 Tipo Muscular/metabolismo , Precursores del ARN/genética , ARN Mensajero/genética , Proteínas de Unión al ARN/genética , Ribonucleoproteína Nuclear Pequeña U1/genética
2.
Nature ; 583(7814): 122-126, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32461692

RESUMEN

The cellular NADH/NAD+ ratio is fundamental to biochemistry, but the extent to which it reflects versus drives metabolic physiology in vivo is poorly understood. Here we report the in vivo application of Lactobacillus brevis (Lb)NOX1, a bacterial water-forming NADH oxidase, to assess the metabolic consequences of directly lowering the hepatic cytosolic NADH/NAD+ ratio in mice. By combining this genetic tool with metabolomics, we identify circulating α-hydroxybutyrate levels as a robust marker of an elevated hepatic cytosolic NADH/NAD+ ratio, also known as reductive stress. In humans, elevations in circulating α-hydroxybutyrate levels have previously been associated with impaired glucose tolerance2, insulin resistance3 and mitochondrial disease4, and are associated with a common genetic variant in GCKR5, which has previously been associated with many seemingly disparate metabolic traits. Using LbNOX, we demonstrate that NADH reductive stress mediates the effects of GCKR variation on many metabolic traits, including circulating triglyceride levels, glucose tolerance and FGF21 levels. Our work identifies an elevated hepatic NADH/NAD+ ratio as a latent metabolic parameter that is shaped by human genetic variation and contributes causally to key metabolic traits and diseases. Moreover, it underscores the utility of genetic tools such as LbNOX to empower studies of 'causal metabolism'.


Asunto(s)
Hígado/metabolismo , NAD/metabolismo , Estrés Fisiológico , Proteínas Adaptadoras Transductoras de Señales/genética , Animales , Citosol/metabolismo , Modelos Animales de Enfermedad , Factores de Crecimiento de Fibroblastos/sangre , Variación Genética , Prueba de Tolerancia a la Glucosa , Humanos , Resistencia a la Insulina , Levilactobacillus brevis/enzimología , Levilactobacillus brevis/genética , Masculino , Ratones , Complejos Multienzimáticos/genética , Complejos Multienzimáticos/metabolismo , NADH NADPH Oxidorreductasas/genética , NADH NADPH Oxidorreductasas/metabolismo , Oxidación-Reducción , Triglicéridos/sangre
3.
Ann Surg Oncol ; 31(7): 4197-4198, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38615151

RESUMEN

BACKGROUND: Up to 41% of intra- and extra-adrenal paragangliomas are linked to germline mutations with autosomal dominant transmission, which necessitates genetic testing for patients and their relatives.1-4 Certain alterations, such as the succinate dehydrogenase (SDH) subunit B gene mutation, are associated with a significant risk of extra-adrenal, malignant, and metastatic disease forms.4-7 This highlights the need for routine genetic counseling and diligent surveillance, as well as surgeon awareness of hereditary paraganglioma-pheochromocytoma syndrome (HPPS). METHODS: We present a multimedia article featuring a step-by-step video of a complex retroperitoneal resection, enriched with perioperative management insights. RESULTS: A 17-year-old female presented with episodes of hypertension, tachycardia, and diffuse diaphoresis. CT revealed a paraaortic mass adjacent to the left renal hilum later confirmed by a SPECT/CT with iodine-123 meta-iodobenzylguanidine.8 Additional imaging with gallium-68 DOTATATE was not performed then due to unknown mutation status. The patient underwent robotic removal of the tumor and adjacent lymph nodes. Pathology confirmed a poorly differentiated paraganglioma with 0/6 lymph node metastases. Genetic tests revealed SDHB gene mutation, indicative of HPPS.9,10 At 12 months, the patient remained disease-free on CT with normalized metanephrines levels and no detectable circulating tumor DNA. Familial screening detected her mother, maternal uncle, and maternal grandfather to be SDHB mutation carriers, although phenotypically silent. CONCLUSIONS: Robotic-assisted resection can be safe and effective for retroperitoneal malignant paragangliomas. However, management extends beyond surgery and requires cascade genetic testing to address familial risks. Because of the high probability of cancer associated with SDHB mutation, lifelong patient surveillance is imperative.


Asunto(s)
Paraganglioma Extraadrenal , Procedimientos Quirúrgicos Robotizados , Humanos , Femenino , Adolescente , Paraganglioma Extraadrenal/cirugía , Paraganglioma Extraadrenal/genética , Paraganglioma Extraadrenal/patología , Procedimientos Quirúrgicos Robotizados/métodos , Neoplasias Retroperitoneales/cirugía , Neoplasias Retroperitoneales/patología , Neoplasias Retroperitoneales/genética , Pronóstico , Feocromocitoma/cirugía , Feocromocitoma/genética , Feocromocitoma/patología
4.
Metabolomics ; 20(2): 36, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38446263

RESUMEN

INTRODUCTION: Sepsis is a highly morbid condition characterized by multi-organ dysfunction resulting from dysregulated inflammation in response to acute infection. Mitochondrial dysfunction may contribute to sepsis pathogenesis, but quantifying mitochondrial dysfunction remains challenging. OBJECTIVE: To assess the extent to which circulating markers of mitochondrial dysfunction are increased in septic shock, and their relationship to severity and mortality. METHODS: We performed both full-scan and targeted (known markers of genetic mitochondrial disease) metabolomics on plasma to determine markers of mitochondrial dysfunction which distinguish subjects with septic shock (n = 42) from cardiogenic shock without infection (n = 19), bacteremia without sepsis (n = 18), and ambulatory controls (n = 19) - the latter three being conditions in which mitochondrial function, proxied by peripheral oxygen consumption, is presumed intact. RESULTS: Nine metabolites were significantly increased in septic shock compared to all three comparator groups. This list includes N-formyl-L-methionine (f-Met), a marker of dysregulated mitochondrial protein translation, and N-lactoyl-phenylalanine (lac-Phe), representative of the N-lactoyl-amino acids (lac-AAs), which are elevated in plasma of patients with monogenic mitochondrial disease. Compared to lactate, the clinical biomarker used to define septic shock, there was greater separation between survivors and non-survivors of septic shock for both f-Met and the lac-AAs measured within 24 h of ICU admission. Additionally, tryptophan was the one metabolite significantly decreased in septic shock compared to all other groups, while its breakdown product kynurenate was one of the 9 significantly increased. CONCLUSION: Future studies which validate the measurement of lac-AAs and f-Met in conjunction with lactate could define a sepsis subtype characterized by mitochondrial dysfunction.


Asunto(s)
Enfermedades Mitocondriales , Sepsis , Choque Séptico , Humanos , Aminoácidos , N-Formilmetionina , Metabolómica , Metionina , Ácido Láctico , Racemetionina
5.
J Natl Compr Canc Netw ; 22(5): 290-298, 2024 07.
Artículo en Inglés | MEDLINE | ID: mdl-39019054

RESUMEN

The NCCN Guidelines for Cutaneous Melanoma (termed Melanoma: Cutaneous) provide multidisciplinary recommendations for diagnostic workup, staging, and treatment of patients. These NCCN Guidelines Insights focus on the update to neoadjuvant systemic therapy options and summarize the new clinical data evaluated by the NCCN panel for the recommended therapies in Version 2.2024 of the NCCN Guidelines for Cutaneous Melanoma.


Asunto(s)
Melanoma , Neoplasias Cutáneas , Humanos , Melanoma/terapia , Melanoma/diagnóstico , Melanoma/patología , Neoplasias Cutáneas/terapia , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/patología , Estadificación de Neoplasias , Oncología Médica/normas , Oncología Médica/métodos
6.
Biogerontology ; 25(4): 627-647, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38240923

RESUMEN

The influence of chronic diseases on various facets of macrophage cellular senescence is poorly understood. This study evaluated the impact of chronic hyperglycemia on the induction of cellular senescence and subsequent immunosurveillance functions in RAW264.7 macrophages. Macrophages were cultured under normal glucose (NG; 5 mM), high glucose (HG; 20 mM), and very high glucose (VHG; 40 mM) conditions and assessed for markers of cellular senescence. Hyperglycemia induced strong upregulation of SA-ß-gal activity, and loss of PCNA and Lamin B1 gene expression while markers of cell cycle arrest generally decreased. Non-significant changes in SASP-related proteins were observed while ROS levels slightly decreased and mitochondrial membrane potential increased. Protein concentration on the exosome membrane surface and their stability appeared to increase under hyperglycemic conditions. However, when macrophages were exposed to the secretory media (SM) of senescent preadipocytes, a dramatic increase in the levels of all inflammatory proteins was recorded especially in the VHG group that was also accompanied by upregulation of NF-κB and NLRP3 gene expression. SM treatment to hyperglycemic macrophages activated the TLR-2/Myd88 pathway but decreased the expression of scavenger receptors RAGE, CD36, and Olr-1 while CD44 and CXCL16 expression increased. On exposure to LPS, a strong upregulation in NO, ROS, and inflammatory cytokines was observed. Together, these results suggest that primary markers of cellular senescence are aberrantly expressed under chronic hyperglycemic conditions in macrophages with no significant SASP activation. Nonetheless, hyperglycemia strongly deregulates macrophage functions leading to impaired immunosurveillance of senescent cells and aggravation of inflamm-aging. This work provides novel insights into how hyperglycemia-induced dysfunctions can impact the potency of macrophages to manage senescent cell burden in aging tissues.


Asunto(s)
Senescencia Celular , Glucosa , Macrófagos , Animales , Senescencia Celular/efectos de los fármacos , Ratones , Macrófagos/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Glucosa/metabolismo , Células RAW 264.7 , Hiperglucemia/metabolismo , Hiperglucemia/inmunología , Biomarcadores/metabolismo , Vigilancia Inmunológica , Especies Reactivas de Oxígeno/metabolismo
7.
J Pept Sci ; : e3602, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38600778

RESUMEN

Targeted therapy of the highest globally incident breast cancer shall resolve the issue of off-target toxicity concurring with augmented killing of specific diseased cells. Thus, the goal of this study was to prepare a peptide-drug conjugate targeting elevated expression of HER2 receptors in breast cancer. Towards this, the rL-A9 peptide was conjugated with the chemotherapeutic drug doxorubicin (DOX) through a N-succinimidyl-4-(N-maleimidomethyl) cyclohexane-1-carboxylate (SMCC) linker. The synthesized peptide-drug conjugate, rL-A9-DOX, was characterized by mass spectrometry. Molecular docking studies, based on binding energy data, suggested a stronger interaction of rL-A9-DOX with the HER2 receptor in comparison to the unconjugated peptide, rL-A9. The cytotoxic effect of the rL-A9-DOX conjugate was observed to be higher in HER2-positive SKOV3 cells compared to HER2-negative MDA-MB-231 cells, indicating selective cell killing. Cellular internalization of the rL-A9-DOX conjugate was evident from the flow cytometry analysis, where a noticeable shift in mean fluorescent intensity (MFI) was observed for the conjugate compared to the control group. This data was further validated by confocal microscopy, where the fluorescent signal ascertained nuclear accumulation of rL-A9-DOX. The present studies highlight the promising potential of rL-A9-DOX for targeted delivery of the drug into a defined group of cancer cells.

8.
Environ Res ; 242: 117795, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38043894

RESUMEN

The increasing burden of cardiovascular disease (CVD) remains responsible for morbidity and mortality worldwide; their effective diagnostic or treatment methods are of great interest to researchers. The use of NPs and nanocarriers in cardiology has drawn much interest. The present comprehensive review provides deep insights into the use of current and innovative approaches in CVD diagnostics to offer practical ways to utilize nanotechnological interventions and the critical elements in the CVD diagnosis, associated risk factors, and management strategies of patients with chronic CVDs. We proposed a decision tree-based solution by discussing the emerging applications of NPs for the higher number of rules to increase efficiency in treating CVDs. This review-based study explores the screening methods, tests, and toxicity to provide a unique way of creating a multi-parametric feature that includes cutting-edge techniques for identifying cardiovascular problems and their treatments. We discussed the benefits and drawbacks of various NPs in the context of cost, space, time and complexity that have been previously suggested in the literature for the diagnosis of CVDs risk factors. Also, we highlighted the advances in using NPs for targeted and improved drug delivery and discussed the evolution toward the nano-cardiovascular potential for medical science. Finally, we also examined the mixed-based diagnostic approaches crucial for treating cardiovascular disorders, broad applications and the potential future applications of nanotechnology in medical sciences.


Asunto(s)
Enfermedades Cardiovasculares , Nanopartículas , Humanos , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/terapia , Nanomedicina/métodos , Sistemas de Liberación de Medicamentos , Nanotecnología
9.
Can J Neurol Sci ; 51(1): 126-128, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36847162

RESUMEN

The use of home video recordings (HVRs) may aid in the diagnosis of neurological disorders. However, this practice remains underutilized. Through an anonymous survey, we sought to understand the perspectives of healthcare providers regarding the sharing of HVRs alongside referrals for responsive and economical pediatric neurology care. This was timely given COVID-19 has worsened wait times for diagnosis and consequently treatment. Most providers agree that sharing of HVRs improves patient care (93.1%: 67/73) and prevents both additional investigations (67%: 49/73) and hospital admissions (68.5%: 50/73). However, a minority of providers (21.9 %: 16/73) currently share HVRs alongside their referrals.


Asunto(s)
Enfermedades del Sistema Nervioso , Neurología , Niño , Humanos , Enfermedades del Sistema Nervioso/terapia , Derivación y Consulta , Personal de Salud , Hospitalización
10.
Cell Biochem Funct ; 42(2): e3970, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38456500

RESUMEN

There is strong evidence that most individuals in the elderly population are characterized by inflamm-aging which refers to a subtle increase in the systemic pro-inflammatory environment and impaired innate immune activation. Although a variety of distinct factors are associated with the progression of inflamm-aging, emerging research is demonstrating a dynamic relationship between the processes of cellular senescence and inflamm-aging. Cellular senescence is a recognized factor governing organismal aging, and through a characteristic secretome, accumulating senescent cells can induce and augment a pro-inflammatory tissue environment that provides a rationale for immune system-independent activation of inflamm-aging and associated diseases. There is also accumulating evidence that inflamm-aging or its components can directly accelerate the development of senescent cells and ultimately senescent cell burden in tissues in a likely vicious inflammatory loop. The present review is intended to describe the emerging senescence-based molecular etiology of inflamm-aging as well as the dynamic reciprocal interactions between inflamm-aging and cellular senescence. Therapeutic interventions concurrently targeting cellular senescence and inflamm-aging are discussed and limitations as well as research opportunities have been deliberated. An effort has been made to provide a rationale for integrating inflamm-aging with cellular senescence both as an underlying cause and therapeutic target for further studies.


Asunto(s)
Envejecimiento , Senescencia Celular , Inflamación , Humanos , Sistema Inmunológico
11.
Reprod Domest Anim ; 59(7): e14675, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39005139

RESUMEN

The aim of this research was to assess genetic parameters for first lactation production and reproduction traits in Murrah buffaloes by employing additive and maternal effects. Data on pedigree and specific traits of 640 Murrah buffaloes were gathered from 1997 to 2020. These traits encompassed first lactation milk yield (FLMY), 305-day first lactation milk yield (305FLMY), first lactation length (FLL), first lactation peak yield (FPY), first service period (FSP), first calving interval (FCI) and first dry period (FDP). Genetic evaluations employed six univariate animal models, accounting for both direct and maternal effects, facilitated by THRGIBBS1F90 and POSTGIBBSF90 programs. Fixed factors included in the analysis were period of calving, season of calving and age at first calving. The Bayesian estimates for direct heritability, derived from the most suitable model, were as follows: FLMY: 0.28 ± 0.01, 305FLMY: 0.30 ± 0.01, FLL: 0.19 ± 0.01, FPY: 0.18 ± 0.01, FSP: 0.12 ± 0.01, FCI: 0.14 ± 0.01 and FDP: 0.12 ± 0.01. Maternal effects were found significant, ranging from 5% to 10%, in first lactation traits under Model 2 and Model 5. Additionally, positive and significant genetic and phenotypic correlations were observed among the studied traits. In conclusion, selection based on 305-day first lactation milk yield suggests potential for genetic enhancement in Murrah buffaloes, advocating its inclusion in breeding programmes to bolster early performance. Also, consideration of maternal influences is necessary for genetic progress of animals.


Asunto(s)
Teorema de Bayes , Búfalos , Lactancia , Reproducción , Animales , Búfalos/fisiología , Búfalos/genética , Femenino , Lactancia/fisiología , Reproducción/fisiología , Reproducción/genética , Leche , Herencia Materna , Cruzamiento , Masculino
12.
Bioprocess Biosyst Eng ; 47(5): 725-736, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38582779

RESUMEN

The global energy crisis has spurred a shift from conventional to clean and sustainable energy sources. Biomass derived from microalgae is emerging as an alternative energy source with diverse applications. Despite the numerous advantages of microalgae, large-scale biomass harvesting is not economical and convenient. Self-flocculation is considered an effective phenomenon facilitated by extracting the flocculating substances from microalgae that assist aggregation of algal cells into flocs. A novel cellulose-based bioflocculant has been synthesized from sewage water grown Chlorella sorokiniana and Scenedesmus abundans for harvesting application. The produced bioflocculant amounted to 38.5% and 19.38% of the dry weight of S. abundans and C. sorokiniana, respectively. Analysis via FTIR, XRD, and FESEM-EDX revealed the presence of cellulose hydroxyapatite (HA) in algae-derived cellulose. Harvesting efficiencies of 95.3% and 89.16% were attained for S. abundans and C. sorokiniana, respectively, at a dosage of 0.5 g/L. Furthermore, the bioflocculant was recovered, enabling its reuse with recovery efficiencies of 52% and 10% for S. abundans and C. sorokiniana, respectively. This simple and efficient approach has the potential to replace other harvesting methods, thereby contributing to the economic algal biofuel production.


Asunto(s)
Celulosa , Chlorella , Floculación , Scenedesmus , Aguas del Alcantarillado , Chlorella/crecimiento & desarrollo , Chlorella/metabolismo , Scenedesmus/crecimiento & desarrollo , Scenedesmus/metabolismo , Celulosa/química , Biomasa , Microalgas/crecimiento & desarrollo , Microalgas/metabolismo
13.
Artículo en Inglés | MEDLINE | ID: mdl-38874619

RESUMEN

The present study optimized pre-treatment conditions for bioenzyme-mediated hydro-distillation (BMHD) for extraction of mint oil from mentha leaves and the results were compared with those of traditional hydro-distillation (HD) method using response surface methodology. The bio-enzymes produced from moringa leaves had maximum pectinase activity (287.04 µg of sugar/min/ml) followed by xylanase (87.78 µg of sugar/min/ml) while endoglucanase, exoglucanase and amylase activities were comparatively low. The optimized conditions for HD were 69.08 temperature for 173.70 min with water:sample of 10.0. The optimized conditions for enzyme pre-treatment of mentha leaves by BMHD were enzyme concentration of 8%, for a period of 120 min at an incubation period of 40 â„ƒ. The yield (%) and menthol content (%) of the oil at optimized conditions by HD were 1.55 ml/100 g of sample and 56.40% menthol content, respectively, and for BMHD the yield and menthol content (%) of the oil at optimized conditions were 3.69% and 72.80%, respectively. It was found that BMHD leads to a 130% increase in the yield of mint oil and a 10% increase in menthol content as compared to the HD method. No significant difference in physical parameters was observed in mint oil extracted via both methods. Therefore, BMHD is a cost-effective and sustainable approach having an edge over the HD method without compromising the quality and could be a viable approach for commercial purposes.

14.
J Labelled Comp Radiopharm ; 67(4): 131-144, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38342496

RESUMEN

Trastuzumab is a US-FDA-approved humanized monoclonal antibody used for the treatment of human epidermal growth factor receptor 2 (HER2)-positive breast cancer. The aim of the present work is to optimize a freeze-dried formulation of DOTA-Trastuzumab conjugate for the preparation of patient doses of [177Lu]Lu-Trastuzumab for radioimmunotherapy of breast cancer. The formulation of [177Lu]Lu-Trastuzumab usually takes a long time, and thus, such a process is not suitable for the routine preparation of this agent in hospital radiopharmacies. To circumvent this, a pre-synthesized DOTA-Trastuzumab conjugate as a freeze-dried formulation is proposed. In the present work, DOTA-Trastuzumab conjugate was subjected to a freeze-drying process after the addition of optimized amounts of radioprotectant and cryoprotectant. [177Lu]Lu-DOTA-Trastuzumab was prepared by incubating the lyophilized powder of the kit vial with medium-specific activity 177LuCl3. The final radiochemical purity of [177Lu]Lu-DOTA-Trastuzumab, prepared using freeze-dried kit, was determined to be >95%. To ascertain the reproducibility of the procedure, six consecutive batches of the freeze-dried formulation were prepared, radiolabeled, and evaluated by carrying out both in vitro and ex vivo studies. The consistency of the results of all the six consecutive batches confirmed the robustness and utility of the in-house optimized freeze-dried formulation for the preparation of patient doses of [177Lu]Lu-Trastuzumab at hospital radiopharmacies.


Asunto(s)
Neoplasias de la Mama , Radioisótopos , Humanos , Femenino , Radioisótopos/uso terapéutico , Trastuzumab , Reproducibilidad de los Resultados , Radiofármacos/uso terapéutico , Neoplasias de la Mama/radioterapia , Lutecio/uso terapéutico
15.
Drug Dev Res ; 85(1): e22138, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38078492

RESUMEN

The continuous pursuit of designing an ideal infection imaging agent is a crucial and ongoing endeavor in the field of biomedical research. Duramycin, an antimicrobial peptide exerts its antimicrobial action on bacteria by specific recognition of phosphatidylethanolamine (PE) moiety present on most bacterial membranes, particularly Escherichia coli (E. coli). E. coli membranes contain more than 60% PE. Therefore, duramycin is an attractive candidate for the formulation of probes for in situ visualization of E. coli driven focal infections. The aim of the present study is to develop 99m Tc labeled duramycin as a single-photon emission computed tomography (SPECT)-based agent to image such infections. Duramycin was successfully conjugated with a bifunctional chelator, hydrazinonicotinamide (HYNIC). PE specificity of HYNIC-duramycin was confirmed by a dye release assay on PE-containing model membranes. Radiolabeling of HYNIC-duramycin with 99m Tc was performed with consistently high radiochemical yield (>90%) and radiochemical purity (>90%). [99m Tc]Tc-HYNIC-duramycin retained its specificity for E. coli, in vitro. SPECT and biodistribution studies showed that the tracer could specifically identify E. coli driven infection at 3 h post injection. While 99m Tc-labeled duramycin is employed for monitoring early response to cancer therapy and cardiotoxicity, the current studies have confirmed, for the first time, the potential of utilizing 99m Tc labeled duramycin as an imaging agent for detecting bacteria. Its application in imaging PE-positive bacteria represents a novel and promising advancement.


Asunto(s)
Bacteriocinas , Escherichia coli , Compuestos de Organotecnecio , Compuestos de Organotecnecio/química , Distribución Tisular , Péptidos/química , Péptidos/metabolismo
16.
Biochemistry ; 62(24): 3533-3547, 2023 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-37729550

RESUMEN

Neurological disorders are often debilitating conditions with no cure. The majority of current therapies are palliative rather than disease-modifying; therefore, new strategies for treating neurological disorders are greatly needed. mRNA-based therapeutics have great potential for treating such neurological disorders; however, challenges with delivery have limited their clinical potential. Lipid nanoparticles (LNPs) are a promising delivery vector for the brain, given their safer toxicity profile and higher efficacy. Despite this, very little is known about LNP-mediated delivery of mRNA into the brain. Here, we employ MC3-based LNPs and successfully deliver Cre mRNA and Cas9 mRNA/Ai9 sgRNA to the adult Ai9 mouse brain; greater than half of the entire striatum and hippocampus was found to be penetrated along the rostro-caudal axis by direct intracerebral injections of MC3 LNP mRNAs. MC3 LNP Cre mRNA successfully transfected cells in the striatum (∼52% efficiency) and hippocampus (∼49% efficiency). In addition, we demonstrate that MC3 LNP Cas9 mRNA/Ai9 sgRNA edited cells in the striatum (∼7% efficiency) and hippocampus (∼3% efficiency). Further analysis demonstrates that MC3 LNPs mediate mRNA delivery to multiple cell types including neurons, astrocytes, and microglia in the brain. Overall, LNP-based mRNA delivery is effective in brain tissue and shows great promise for treating complex neurological disorders.


Asunto(s)
Nanopartículas , Enfermedades del Sistema Nervioso , Animales , Ratones , ARN Guía de Sistemas CRISPR-Cas , Encéfalo , ARN Mensajero/genética , ARN Interferente Pequeño
17.
Carcinogenesis ; 44(8-9): 650-661, 2023 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-37701974

RESUMEN

OBJECTIVE: Hepatocellular carcinoma (HCC) is one of the leading cancer types with increasing annual incidence and high mortality in the USA. MicroRNAs (miRNAs) have emerged as valuable prognostic indicators in cancer patients. To identify a miRNA signature predictive of survival in patients with HCC, we developed a machine learning-based HCC survival estimation method, HCCse, using the miRNA expression profiles of 122 patients with HCC. METHODS: The HCCse method was designed using an optimal feature selection algorithm incorporated with support vector regression. RESULTS: HCCse identified a robust miRNA signature consisting of 32 miRNAs and obtained a mean correlation coefficient (R) and mean absolute error (MAE) of 0.87 ±â€…0.02 and 0.73 years between the actual and estimated survival times of patients with HCC; and the jackknife test achieved an R and MAE of 0.73 and 0.97 years between actual and estimated survival times, respectively. The identified signature has seven prognostic miRNAs (hsa-miR-146a-3p, hsa-miR-200a-3p, hsa-miR-652-3p, hsa-miR-34a-3p, hsa-miR-132-5p, hsa-miR-1301-3p and hsa-miR-374b-3p) and four diagnostic miRNAs (hsa-miR-1301-3p, hsa-miR-17-5p, hsa-miR-34a-3p and hsa-miR-200a-3p). Notably, three of these miRNAs, hsa-miR-200a-3p, hsa-miR-1301-3p and hsa-miR-17-5p, also displayed association with tumor stage, further emphasizing their clinical relevance. Furthermore, we performed pathway enrichment analysis and found that the target genes of the identified miRNA signature were significantly enriched in the hepatitis B pathway, suggesting its potential involvement in HCC pathogenesis. CONCLUSIONS: Our study developed HCCse, a machine learning-based method, to predict survival in HCC patients using miRNA expression profiles. We identified a robust miRNA signature of 32 miRNAs with prognostic and diagnostic value, highlighting their clinical relevance in HCC management and potential involvement in HCC pathogenesis.


Asunto(s)
Carcinoma Hepatocelular , Hepatitis B , Neoplasias Hepáticas , MicroARNs , Humanos , Carcinoma Hepatocelular/patología , Pronóstico , Neoplasias Hepáticas/patología , MicroARNs/genética , MicroARNs/metabolismo
18.
Bioconjug Chem ; 34(9): 1576-1584, 2023 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-37379455

RESUMEN

The retro analog of the HER2-targeting A9 peptide was synthesized by coupling amino acids in a reverse fashion and switching the N-terminal in the original sequence of the L-A9 peptide (QDVNTAVAW) to the C-terminal in rL-A9 (WAVATNVDQ). Modification in the backbone resulted in higher conformational stability of the retro peptide as evident from CD spectra. Molecular docking analysis revealed a higher HER2 binding affinity of [177Lu]Lu-DOTA-rL-A9 than the original radiopeptide [177Lu]Lu-DOTA-L-A9. Enormously enhanced metabolic stability of the retro analog led to significant elevation in tumor uptake and retention. SPECT imaging studies corroborated biodistribution results demonstrating a remarkably higher tumor signal for [177Lu]Lu-DOTA-rL-A9. The presently studied retro probe has promising efficiency for clinical screening.


Asunto(s)
Péptidos , Distribución Tisular , Simulación del Acoplamiento Molecular , Línea Celular Tumoral , Transporte Biológico
19.
Epilepsia ; 64(5): e75-e81, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36809544

RESUMEN

Children with epilepsy commonly have comorbid neurocognitive impairments that severely affect their psychosocial well-being, education, and future career prospects. Although the provenance of these deficits is multifactorial, the effects of interictal epileptiform discharges (IEDs) and anti-seizure medications (ASMs) are thought to be particularly severe. Although certain ASMs can be leveraged to inhibit IED occurrence, it remains unclear whether epileptiform discharges or the medications themselves are most deleterious to cognition. To examine this question, 25 children undergoing invasive monitoring for refractory focal epilepsy performed one or more sessions of a cognitive flexibility task. Electrophysiological data were recorded to detect IEDs. Between repeated sessions, prescribed ASMs were either continued or titrated to <50% of the baseline dose. Hierarchical mixed-effects modeling assessed the relationship between task reaction time (RT), IED occurrence, ASM type, and dose while controlling for seizure frequency. Both presence (ß ± SE = 49.91 ± 16.55 ms, p = .003) and number of IEDs (ß ± SE = 49.84 ± 12.51 ms, p < .001) were associated with slowed task RT. Higher dose oxcarbazepine significantly reduced IED frequency (p = .009) and improved task performance (ß ± SE = -107.43 ± 39.54 ms, p = .007). These results emphasize the neurocognitive consequences of IEDs independent of seizure effects. Furthermore, we demonstrate that inhibition of IEDs following treatment with select ASMs is associated with improved neurocognitive function.


Asunto(s)
Epilepsia Refractaria , Epilepsias Parciales , Epilepsia , Niño , Humanos , Electroencefalografía/métodos , Epilepsia/complicaciones , Epilepsia/tratamiento farmacológico , Epilepsias Parciales/complicaciones , Epilepsias Parciales/tratamiento farmacológico , Cognición/fisiología , Epilepsia Refractaria/complicaciones
20.
Crit Rev Food Sci Nutr ; 63(12): 1755-1791, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-34433338

RESUMEN

Several studies have reported the health-beneficial effects of dietary phytochemicals, namely polyphenols, to prevent various diseases, including cancer. Polyphenols, like (-)-epigallocatechin-3-gallate (EGCG) from green tea, curcumin from turmeric, and ellagic acid from pomegranate are known to act by modulating antioxidant, anti-inflammatory and apoptotic signal transduction pathways in the tumor milieu. The evolving literature underscores the role of epigenetic regulation of genes associated with cancer by these polyphenols, primarily via non-coding RNAs (ncRNAs), such as microRNAs (miRNA) and long noncoding RNA (lncRNA). However, there is little clarity on the exact role(s) played by these ncRNAs and their interactions with other ncRNAs, or with their protein targets, in response to modulation by these dietary polyphenols. Here, we review ncRNA interactions and functional networks of the complex ncRNA interactome with their targets in preclinical studies along with the role of epigenetics as well as key aspects of pharmacokinetics and phytochemistry of dietary polyphenols. We also summarize the current state of clinical trials with these dietary polyphenols. Taken together, this synthetic review provides insights into the molecular aspects underlying the anticancer chemopreventive effects of dietary polyphenols as well as summarizes data on novel biomarkers modulated by these polyphenols for preventive or therapeutic purposes in various types of cancer.


Asunto(s)
Catequina , MicroARNs , Neoplasias , Humanos , Epigénesis Genética , Polifenoles/química , Neoplasias/genética , Neoplasias/prevención & control , Neoplasias/tratamiento farmacológico , Quimioprevención , Catequina/uso terapéutico , MicroARNs/genética , Té/química
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