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1.
Toxicol In Vitro ; 101: 105935, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39243829

RESUMO

The general population is exposed to many chemicals which have putative, but incompletely understood, links to breast cancer. Cell Painting is a high-content imaging-based in vitro assay that allows for unbiased measurements of concentration-dependent effects of chemical exposures on cellular morphology. We used Cell Painting to measure effects of 16 human exposure relevant chemicals, along with 21 small molecules with known mechanisms of action, in non-tumorigenic mammary epithelial cells, the MCF10A cell line. Using CellProfiler image analysis software, we quantified 3042 morphological features across approximately 1.2 million cells. We used benchmark concentration modeling to identify features both conserved and different across chemicals. Benchmark concentrations were compared to exposure biomarker concentration measurements from the National Health and Nutrition Examination Survey to assess which chemicals induce morphological alterations at human-relevant concentrations. We found significant feature overlaps between chemicals, including similarities between the organochlorine pesticide DDT metabolite p,p'-DDE and an activator of Wnt signaling CHIR99201. We validated these findings by assaying the activation of Wnt, as reflected by translocation of ꞵ-catenin, following p'-p' DDE exposure. Consistent with Wnt signaling activation, low concentration p',p'-DDE (25 nM) significantly enhanced the nuclear translocation of ꞵ-catenin. Overall, these findings highlight the ability of Cell Painting to enhance mode-of-action studies for toxicants which are common in our environment but incompletely characterized with respect to breast cancer risk.

2.
J Vasc Surg Cases Innov Tech ; 10(5): 101559, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39157576

RESUMO

Upper extremity acute limb ischemia (ALI) owing to obstruction proximal to the vertebral artery poses the risk of posterior stroke during intervention. We describe a case of upper extremity ALI secondary to thrombosis of the proximal left subclavian artery with thromboembolic occlusion at the brachial bifurcation. The patient underwent a hybrid procedure of open thromboembolectomy with endovascular vertebral artery embolic protection. The patient's distal pulses and upper extremity function returned to baseline, without evidence of posterior stroke. A literature review revealed limited reports of the use of cerebral embolic protection in the setting of emergent thromboembolectomy for upper extremity ALI.

3.
Cell Rep ; 43(8): 114607, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39126652

RESUMO

Macrophage metabolic plasticity is central to inflammatory programming, yet mechanisms of coordinating metabolic and inflammatory programs during infection are poorly defined. Here, we show that type I interferon (IFN) temporally guides metabolic control of inflammation during methicillin-resistant Staphylococcus aureus (MRSA) infection. We find that staggered Toll-like receptor and type I IFN signaling in macrophages permit a transient energetic state of combined oxidative phosphorylation (OXPHOS) and aerobic glycolysis followed by inducible nitric oxide synthase (iNOS)-mediated OXPHOS disruption. This disruption promotes type I IFN, suppressing other pro-inflammatory cytokines, notably interleukin-1ß. Upon infection, iNOS expression peaks at 24 h, followed by lactate-driven Nos2 repression via histone lactylation. Type I IFN pre-conditioning prolongs infection-induced iNOS expression, amplifying type I IFN. Cutaneous MRSA infection in mice constitutively expressing epidermal type I IFN results in elevated iNOS levels, impaired wound healing, vasculopathy, and lung infection. Thus, kinetically regulated type I IFN signaling coordinates immunometabolic checkpoints that control infection-induced inflammation.


Assuntos
Inflamação , Interferon Tipo I , Macrófagos , Staphylococcus aureus Resistente à Meticilina , Óxido Nítrico Sintase Tipo II , Transdução de Sinais , Infecções Estafilocócicas , Animais , Interferon Tipo I/metabolismo , Inflamação/patologia , Inflamação/metabolismo , Camundongos , Óxido Nítrico Sintase Tipo II/metabolismo , Infecções Estafilocócicas/imunologia , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/metabolismo , Infecções Estafilocócicas/patologia , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Macrófagos/metabolismo , Macrófagos/imunologia , Macrófagos/microbiologia , Camundongos Endogâmicos C57BL , Fosforilação Oxidativa , Glicólise , Interleucina-1beta/metabolismo
4.
bioRxiv ; 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38853980

RESUMO

Members of the Bacteroidota compose a large portion of the human gut microbiota, contributing to overall gut health via the degradation of various polysaccharides. This process is facilitated by lipoproteins, globular proteins anchored to the cell surface by a lipidated N-terminal cysteine. Despite their importance, lipoprotein synthesis by these bacteria is understudied. In E. coli, the α-amino linked lipid of lipoproteins is added by the lipoprotein N-acyltransferase Lnt. Herein, we have identified a protein distinct from Lnt responsible for the same process in Bacteroides, named lipoprotein N-acyltransferase in Bacteroides (Lnb). Deletion of Lnb yields cells that synthesize diacylated lipoproteins, with impacts on cell viability and morphology, growth on polysaccharides, and protein composition of membranes and outer membrane vesicles (OMVs). Our results not only challenge the accepted paradigms of lipoprotein biosynthesis in Gram-negative bacteria, but also support the establishment of a new family of lipoprotein N-acyltransferases.

5.
Front Oncol ; 14: 1411295, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38915368

RESUMO

Introduction: Breast cancer is the second most diagnosed cancer, as well as the primary cause of cancer death in women worldwide. Of the different breast cancer subtypes, triple-negative breast cancer (TNBC) is particularly aggressive and is associated with poor prognosis. Black women are two to three times more likely to be diagnosed with TNBCs than white women. Recent experimental evidence suggests that basal-like TNBCs may derive from luminal cells which acquire basal characteristics through phenotypic plasticity, a newly recognized hallmark of cancer. Whether chemical exposures can promote phenotypic plasticity in breast cells is poorly understood. Methods: To investigate further, we developed a high-content immunocytochemistry assay using normal human breast cells to test whether chemical exposures can impact luminal/basal plasticity by unbiased quantification of keratin 14 (KRT14), a basal-myoepithelial marker; keratin 8 (KRT8), a luminal-epithelial marker; and Hoechst 33342, a DNA marker. Six cell lines established from healthy tissue from donors to the Susan G. Komen Normal Tissue Bank were exposed for 48 hours to three different concentrations (0.1µM, 1µM, and 10µM) of eight ubiquitous chemicals (arsenic, BPA, BPS, cadmium, copper, DDE, lead, and PFNA), with documented exposure disparities in US Black women, in triplicate. Automated fluorescence image quantification was performed using Cell Profiler software, and a random-forest classifier was trained to classify individual cells as KRT8 positive, KRT14 positive, or hybrid (both KRT8 and KRT14 positive) using Cell Profiler Analyst. Results and discussion: Results demonstrated significant concentration-dependent increases in hybrid populations in response to BPA, BPS, DDE, and PFNA. The increase in hybrid populations expressing both KRT14 and KRT8 is indicative of a phenotypically plastic progenitor-like population in line with known theories of carcinogenesis. Furthermore, BPA, BPS, DDE, and copper produced significant increases in cell proliferation, which could be indicative of a more malignant phenotype. These results further elucidate the relationship between chemical exposure and breast phenotypic plasticity and highlight potential environmental factors that may impact TNBC risk.

6.
Clin Case Rep ; 12(6): e8831, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38799541

RESUMO

Inferior vena cava atresia is a rare condition with highly variable anatomy due to the complexity of caval embryology. When endovascular venovenous reconstruction is considered for severe persistent sequelae, multimodality imaging with CT and invasive venography is used to determine the appropriateness of intervention and for procedural planning.

7.
bioRxiv ; 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38746407

RESUMO

There are a substantial number of chemicals to which individuals in the general population are exposed which have putative, but still poorly understood, links to breast cancer. Cell Painting is a high-content imaging-based in vitro assay that allows for rapid and unbiased measurements of the concentration-dependent effects of chemical exposures on cellular morphology. We optimized the Cell Painting assay and measured the effect of exposure to 16 human exposure relevant chemicals, along with 21 small molecules with known mechanisms of action, for 48 hours in non-tumorigenic mammary epithelial cells, the MCF10A cell line. Through unbiased imaging analyses using CellProfiler, we quantified 3042 morphological features across approximately 1.2 million cells. We used benchmark concentration modeling to quantify significance and dose-dependent directionality to identify morphological features conserved across chemicals and find features that differentiate the effects of toxicants from one another. Benchmark concentrations were compared to chemical exposure biomarker concentration measurements from the National Health and Nutrition Examination Survey to assess which chemicals induce morphological alterations at human-relevant concentrations. Morphometric fingerprint analysis revealed similar phenotypes between small molecules and prioritized NHANES-toxicants guiding further investigation. A comparison of feature fingerprints via hypergeometric analysis revealed significant feature overlaps between chemicals when stratified by compartment and stain. One such example was the similarities between a metabolite of the organochlorine pesticide DDT (p,p'-DDE) and an activator of canonical Wnt signaling CHIR99201. As CHIR99201 is a known Wnt pathway activator and its role in ß-catenin translocation is well studied, we studied the translocation of ß-catenin following p'-p' DDE exposure in an orthogonal high-content imaging assay. Consistent with activation of Wnt signaling, low dose p',p'-DDE (25nM) significantly enhances the nuclear translocation of ß-catenin. Overall, these findings highlight the ability of Cell Painting to enhance mode-of-action studies for toxicants which are common exposures in our environment but have previously been incompletely characterized with respect to breast cancer risk.

8.
bioRxiv ; 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38712240

RESUMO

Acute inflammation, characterized by a rapid influx of neutrophils, is a protective response that can lead to chronic inflammatory diseases when left unresolved. Secretion of LTB 4 -containing exosomes is required for effective neutrophil infiltration during inflammation. In this study, we show that neutrophils release nuclear DNA in a non-lytic, rapid, and repetitive manner, via a mechanism distinct from suicidal NET release and cell death. The packaging of nuclear DNA occurs in the lumen of nuclear envelope (NE)-derived multivesicular bodies (MVBs) that harbor the LTB 4 synthesizing machinery and is mediated by the lamin B receptor (LBR) and chromatin decondensation. Disruption of secreted exosome-associated DNA (SEAD) in a model of sterile inflammation in mouse skin amplifies and prolongs the presence of neutrophils, impeding the onset of resolution. Together, these findings advance our understanding of neutrophil functions during inflammation and the physiological significance of NETs, with implications for novel treatments for inflammatory disorders.

9.
ACS Nano ; 18(15): 10439-10453, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38567994

RESUMO

The cGAS-STING pathway plays a crucial role in innate immune activation against cancer and infections, and STING agonists based on cyclic dinucleotides (CDN) have garnered attention for their potential use in cancer immunotherapy and vaccines. However, the limited drug-like properties of CDN necessitate an efficient delivery system to the immune system. To address these challenges, we developed an immunostimulatory delivery system for STING agonists. Here, we have examined aqueous coordination interactions between CDN and metal ions and report that CDN mixed with Zn2+ and Mn2+ formed distinctive crystal structures. Further pharmaceutical engineering led to the development of a functional coordination nanoparticle, termed the Zinc-Mn-CDN Particle (ZMCP), produced by a simple aqueous one-pot synthesis. Local or systemic administration of ZMCP exerted robust antitumor efficacy in mice. Importantly, recombinant protein antigens from SARS-CoV-2 can be simply loaded during the aqueous one-pot synthesis. The resulting ZMCP antigens elicited strong cellular and humoral immune responses that neutralized SARS-CoV-2, highlighting ZMCP as a self-adjuvant vaccine platform against COVID-19 and other infectious pathogens. Overall, this work establishes a paradigm for developing translational coordination nanomedicine based on drug-metal ion coordination and broadens the applicability of coordination medicine for the delivery of proteins and other biologics.


Assuntos
Nanopartículas , Neoplasias , Vacinas , Animais , Camundongos , Neoplasias/terapia , Adjuvantes Imunológicos , Imunoterapia/métodos , Nanopartículas/química
10.
J Food Prot ; 87(6): 100272, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38579970

RESUMO

Hand hygiene is broadly recognized as a critical intervention in reducing the spread of disease-causing pathogens in both professional and personal uses. In this study, the impact of antibacterial (AB) or nonantibacterial soaps on the removal and postwash transfer of E. coli following the handling of raw poultry was assessed. Baseline bacterial contamination ranged between 107 and 109 CFU per hand. Hands were washed for 30 s in 40°C ± 2°C tap water using 2 mL of AB soap (0.5% and 1.0% Chloroxylenol, 0.5% Benzalkonium Chloride, or 4.0% Chlorhexidine Gluconate), non-AB soap (cosmetic/plain soap), or water. Postwash, water, and non-AB soap had a mean 3.63 and 3.65 Log10 reduction of E. coli on hands. AB treatments had a mean 4.19-4.35 Log10 reduction. Rinse water had mean bacterial counts of 8.62 and 8.88 Log10 CFU/mL for non-AB soap and water and 5.37-6.90 Log10 CFU/mL for AB treatments. Bacterial transfer was assessed by following the test subject's handling of a sterile polymer knife handle for 30 s postwash. E. coli transfer ranged from 263 to 903 CFU/handle for AB soaps and 1572 or 1709 CFU/handle for water and non-AB soap. Differences between AB and non-AB treatments were statistically significant (p < 0.0001) for hands and rinse water. Differences in transfer from hands to knife handle were not statistically significant (p = 0.139). Combined, these data highlight significant differences in the performance of AB soaps relative to non-AB soaps in a food handling environment-specific usage example and provide an unexplored assessment of the bactericidal vs. removal effects of AB vs. non-AB soaps on bacteria removed from the hands. These data reinforce the importance of hand hygiene, provide new details on the differences between AB vs. non-AB soaps, and highlight potential differences to inform food handling environment operators and public health personnel on how these products may impact food safety.


Assuntos
Antibacterianos , Contagem de Colônia Microbiana , Escherichia coli , Aves Domésticas , Sabões , Animais , Humanos , Escherichia coli/efeitos dos fármacos , Sabões/farmacologia , Antibacterianos/farmacologia , Desinfecção das Mãos , Mãos/microbiologia , Manipulação de Alimentos/métodos , Contaminação de Alimentos/análise , Desinfetantes/farmacologia , Higiene das Mãos , Microbiologia de Alimentos
11.
Assay Drug Dev Technol ; 22(3): 148-159, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38526231

RESUMO

The progression of type II diabetes (T2D) is characterized by a complex and highly variable loss of beta-cell mass, resulting in impaired insulin secretion. Many T2D drug discovery efforts aimed at discovering molecules that can protect or restore beta-cell mass and function have been developed using limited beta-cell lines and primary rodent/human pancreatic islets. Various high-throughput screening methods have been used in the context of drug discovery, including luciferase-based reporter assays, glucose-stimulated insulin secretion, and high-content screening. In this context, a cornerstone of small molecule discovery has been the use of immortalized rodent beta-cell lines. Although insightful, this usage has led to a more comprehensive understanding of rodent beta-cell proliferation pathways rather than their human counterparts. Advantages gained in enhanced physiological relevance are offered by three-dimensional (3D) primary islets and pseudoislets in contrast to monolayer cultures, but these approaches have been limited to use in low-throughput experiments. Emerging methods, such as high-throughput 3D islet imaging coupled with machine learning, aim to increase the feasibility of integrating 3D microtissue structures into high-throughput screening. This review explores the current methods used in high-throughput screening for small molecule modulators of beta-cell mass and function, a potentially pivotal strategy for diabetes drug discovery.


Assuntos
Descoberta de Drogas , Ensaios de Triagem em Larga Escala , Células Secretoras de Insulina , Bibliotecas de Moléculas Pequenas , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Humanos , Animais , Bibliotecas de Moléculas Pequenas/farmacologia , Bibliotecas de Moléculas Pequenas/química , Regeneração/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo
12.
bioRxiv ; 2024 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-38352460

RESUMO

Inter-organellar communication is critical for cellular metabolic homeostasis. One of the most abundant inter-organellar interactions are those at the endoplasmic reticulum and mitochondria contact sites (ERMCS). However, a detailed understanding of the mechanisms governing ERMCS regulation and their roles in cellular metabolism are limited by a lack of tools that permit temporal induction and reversal. Through unbiased screening approaches, we identified fedratinib, an FDA-approved drug, that dramatically increases ERMCS abundance by inhibiting the epigenetic modifier BRD4. Fedratinib rapidly and reversibly modulates mitochondrial and ER morphology and alters metabolic homeostasis. Moreover, ERMCS modulation depends on mitochondria electron transport chain complex III function. Comparison of fedratinib activity to other reported inducers of ERMCS revealed common mechanisms of induction and function, providing clarity and union to a growing body of experimental observations. In total, our results uncovered a novel epigenetic signaling pathway and an endogenous metabolic regulator that connects ERMCS and cellular metabolism.

13.
J Virol ; 97(12): e0127623, 2023 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-37975674

RESUMO

ABSTRACT: Disease progression during SARS-CoV-2 infection is tightly linked to the fate of lung epithelial cells, with severe cases of COVID-19 characterized by direct injury of the alveolar epithelium and an impairment in its regeneration from progenitor cells. The molecular pathways that govern respiratory epithelial cell death and proliferation during SARS-CoV-2 infection, however, remain unclear. We now report a high-throughput CRISPR screen for host genetic modifiers of the survival and proliferation of SARS-CoV-2-infected Calu-3 respiratory epithelial cells. The top four genes identified in our screen encode components of the same type I interferon (IFN-I) signaling complex­IFNAR1, IFNAR2, JAK1, and TYK2. The fifth gene, ACE2, was an expected control encoding the SARS-CoV-2 viral receptor. Surprisingly, despite the antiviral properties of IFN-I signaling, its disruption in our screen was associated with an increase in Calu-3 cell fitness. We validated this effect and found that IFN-I signaling did not sensitize SARS-CoV-2-infected cultures to cell death but rather inhibited the proliferation of surviving cells after the early peak of viral replication and cytopathic effect. We also found that IFN-I signaling alone, in the absence of viral infection, was sufficient to induce this delayed antiproliferative response in both Calu-3 cells and iPSC-derived type 2 alveolar epithelial cells. Together, these findings highlight a cell autonomous antiproliferative response by respiratory epithelial cells to persistent IFN-I signaling during SARS-CoV-2 infection. This response may contribute to the deficient alveolar regeneration that has been associated with COVID-19 lung injury and represents a promising area for host-targeted therapeutic development.


Assuntos
COVID-19 , Células Epiteliais , Interferon Tipo I , Pulmão , Humanos , COVID-19/imunologia , COVID-19/patologia , COVID-19/virologia , Células Epiteliais/patologia , Células Epiteliais/virologia , Interferon Tipo I/imunologia , Pulmão/patologia , Pulmão/virologia , SARS-CoV-2/imunologia , SARS-CoV-2/patogenicidade , Linhagem Celular , Proliferação de Células
14.
medRxiv ; 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37961189

RESUMO

Background: Due to its indolent nature, nontuberculous mycobacteria (NTM) are increasing in global prevalence as a cause of pulmonary infections and are difficult to treat with traditional antibiotics. Here, we study the repurposing of clofazimine (CFZ) to treat NTM through expanded access in a single health system. Our main objectives are to describe the feasibility of accessing and analyzing expanded access data and to generate hypotheses regarding CFZ use in NTM treatment. Methods: A retrospective chart review was performed on patients within a single health system who had been approved for expanded access of clofazimine or who received it through an outside hospital for NTM treatment. Data were collected on patients' baseline demographics, details of their NTM infection, concomitant therapies, and results as of 30 June 2021. Results: A total of 55 patients were identified upon initial review as potentially receiving CFZ for NTM infection. After excluding 19 patients who did not initiate CFZ, data from the remaining 36 patients were collected and summarized. The median age at which patients were diagnosed with NTM was 51.3 years old, with a median BMI of 21.2 kg/m2. Patients were more likely to be female (64%), have a baseline lung disease (72%), and 52% were current or former smokers at the time of their diagnosis. The most common species isolated was M. avium complex (47%) followed by M. abscessus (36%), with the most common site of infection being the lung (78%). The majority of patients presented with productive cough with excess sputum production followed by pulmonary nodules and bronchiectasis present on radiograph. Conclusions: This study demonstrated the difficulty of collecting retrospective real-world data via electronic healthcare records on symptoms, side effects, and radiography from patients who obtained a drug through expanded access. Based on the findings of this study, we recommend further research into the potential use of CFZ in patients with M. abscessus pulmonary infections.

15.
Cytometry A ; 103(11): 915-926, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37789738

RESUMO

Quantitative microscopy is a powerful method for performing phenotypic screens from which image-based profiling can extract a wealth of information, termed profiles. These profiles can be used to elucidate the changes in cellular phenotypes across cell populations from different patient samples or following genetic or chemical perturbations. One such image-based profiling method is the Cell Painting assay, which provides morphological insight through the imaging of eight cellular compartments. Here, we examine the performance of the Cell Painting assay across multiple high-throughput microscope systems and find that all are compatible with this assay. Furthermore, we determine independently for each microscope system the best performing settings, providing those who wish to adopt this assay an ideal starting point for their own assays. We also explore the impact of microscopy setting changes in the Cell Painting assay and find that few dramatically reduce the quality of a Cell Painting profile, regardless of the microscope used.


Assuntos
Bioensaio , Microscopia , Humanos , Microscopia/métodos , Bioensaio/métodos
16.
NPJ Regen Med ; 8(1): 48, 2023 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-37689780

RESUMO

Alveolar type 2 (AT2) cells function as stem cells in the adult lung and aid in repair after injury. The current study aimed to understand the signaling events that control differentiation of this therapeutically relevant cell type during human development. Using lung explant and organoid models, we identified opposing effects of TGFß- and BMP-signaling, where inhibition of TGFß- and activation of BMP-signaling in the context of high WNT- and FGF-signaling efficiently differentiated early lung progenitors into AT2-like cells in vitro. AT2-like cells differentiated in this manner exhibit surfactant processing and secretion capabilities, and long-term commitment to a mature AT2 phenotype when expanded in media optimized for primary AT2 culture. Comparing AT2-like cells differentiated with TGFß-inhibition and BMP-activation to alternative differentiation approaches revealed improved specificity to the AT2 lineage and reduced off-target cell types. These findings reveal opposing roles for TGFß- and BMP-signaling in AT2 differentiation and provide a new strategy to generate a therapeutically relevant cell type in vitro.

18.
SLAS Discov ; 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37527729

RESUMO

Diabetes poses a global health crisis affecting individuals across age groups and backgrounds, with a prevalence estimate of 700 million people worldwide by 2045. Current therapeutic strategies primarily rely on insulin therapy or hypoglycemic agents, which fail to address the root cause of the disease - the loss of pancreatic insulin-producing beta-cells. Therefore, bioassays that recapitulate intact islets are needed to enable drug discovery for beta-cell replenishment, protection from beta-cell loss, and islet-cell interactions. Standard cancer insulinoma beta-cell lines MIN6 and INS-1 have been used to interrogate beta-cell metabolic pathways and function but are not suitable for studying proliferative effects. Screening using primary human/rodent intact islets offers a higher level of physiological relevance to enhance diabetes drug discovery and development. However, the 3-dimensionality of intact islets have presented challenges in developing robust, high-throughput assays to detect beta-cell proliferative effects. Established methods rely on either dissociated islet cells plated in 2D monolayer cultures for imaging or reconstituted pseudo-islets formed in round bottom plates to achieve homogeneity. These approaches have significant limitations due to the islet cell dispersion process. To address these limitations, we have developed a robust, intact ex vivo pancreatic islet bioassay in 384-well format that is capable of detecting diabetes-relevant endpoints including beta-cell proliferation, chemoprotection, and islet spatial morphometrics.

19.
Proc Natl Acad Sci U S A ; 120(30): e2221809120, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37459541

RESUMO

Early in the COVID-19 pandemic, data suggested that males had a higher risk of developing severe disease and that androgen deprivation therapy might be associated with protection. Combined with the fact that TMPRSS2 (transmembrane serine protease 2), a host entry factor for the SARS-CoV-2 virus, was a well-known androgen-regulated gene, this led to an upsurge of research investigating androgen receptor (AR)-targeting drugs. Proxalutamide, an AR antagonist, was shown in initial clinical studies to benefit COVID-19 patients; however, further validation is needed as one study was retracted. Due to continued interest in proxalutamide, which is in phase 3 trials, we examined its ability to impact SARS-CoV-2 infection and downstream inflammatory responses. Proxalutamide exerted similar effects as enzalutamide, an AR antagonist prescribed for advanced prostate cancer, in decreasing AR signaling and expression of TMPRSS2 and angiotensin-converting enzyme 2 (ACE2), the SARS-CoV-2 receptor. However, proxalutamide led to degradation of AR protein, which was not observed with enzalutamide. Proxalutamide inhibited SARS-CoV-2 infection with an IC50 value of 97 nM, compared to 281 nM for enzalutamide. Importantly, proxalutamide inhibited infection by multiple SARS-CoV-2 variants and synergized with remdesivir. Proxalutamide protected against cell death in response to tumor necrosis factor alpha and interferon gamma, and overall survival of mice was increased with proxalutamide treatment prior to cytokine exposure. Mechanistically, we found that proxalutamide increased levels of NRF2, an essential transcription factor that mediates antioxidant responses, and decreased lung inflammation. These data provide compelling evidence that proxalutamide can prevent SARS-CoV-2 infection and cytokine-induced lung damage, suggesting that promising clinical data may emerge from ongoing phase 3 trials.


Assuntos
COVID-19 , Neoplasias da Próstata , Masculino , Humanos , Animais , Camundongos , SARS-CoV-2/metabolismo , Androgênios , Antagonistas de Androgênios/uso terapêutico , Pandemias , Peptidil Dipeptidase A/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Interferon gama/uso terapêutico
20.
Cells ; 12(13)2023 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-37443734

RESUMO

Neural tube defects (NTDs), including anencephaly and spina bifida, are common major malformations of fetal development resulting from incomplete closure of the neural tube. These conditions lead to either universal death (anencephaly) or severe lifelong complications (spina bifida). Despite hundreds of genetic mouse models of neural tube defect phenotypes, the genetics of human NTDs are poorly understood. Furthermore, pharmaceuticals, such as antiseizure medications, have been found clinically to increase the risk of NTDs when administered during pregnancy. Therefore, a model that recapitulates human neurodevelopment would be of immense benefit to understand the genetics underlying NTDs and identify teratogenic mechanisms. Using our self-organizing single rosette cortical organoid (SOSR-COs) system, we have developed a high-throughput image analysis pipeline for evaluating the SOSR-CO structure for NTD-like phenotypes. Similar to small molecule inhibition of apical constriction, the antiseizure medication valproic acid (VPA), a known cause of NTDs, increases the apical lumen size and apical cell surface area in a dose-responsive manner. GSK3ß and HDAC inhibitors caused similar lumen expansion; however, RNA sequencing suggests VPA does not inhibit GSK3ß at these concentrations. The knockout of SHROOM3, a well-known NTD-related gene, also caused expansion of the lumen, as well as reduced f-actin polarization. The increased lumen sizes were caused by reduced cell apical constriction, suggesting that impingement of this process is a shared mechanism for VPA treatment and SHROOM3-KO, two well-known causes of NTDs. Our system allows the rapid identification of NTD-like phenotypes for both compounds and genetic variants and should prove useful for understanding specific NTD mechanisms and predicting drug teratogenicity.


Assuntos
Anencefalia , Defeitos do Tubo Neural , Disrafismo Espinal , Gravidez , Feminino , Humanos , Camundongos , Animais , Ácido Valproico/farmacologia , Anencefalia/complicações , Anencefalia/genética , Glicogênio Sintase Quinase 3 beta/genética , Camundongos Knockout , Defeitos do Tubo Neural/induzido quimicamente , Defeitos do Tubo Neural/genética , Disrafismo Espinal/genética , Encéfalo/patologia , Proteínas dos Microfilamentos
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