Browsing by Author "Gaston, Benjamin"
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Item Androgen regulation of pulmonary AR, TMPRSS2 and ACE2 with implications for sex-discordant COVID-19 outcomes(Nature, 2021-05-27) Baratchian, Mehdi; McManus, Jeffrey M.; Berk, Mike P.; Nakamura, Fumihiko; Mukhopadhyay, Sanjay; Xu, Weiling; Erzurum, Serpil; Drazba, Judy; Peterson, John; Klein, Eric A.; Gaston, Benjamin; Sharifi, Nima; Pediatrics, School of MedicineThe sex discordance in COVID-19 outcomes has been widely recognized, with males generally faring worse than females and a potential link to sex steroids. A plausible mechanism is androgen-induced expression of TMPRSS2 and/or ACE2 in pulmonary tissues that may increase susceptibility or severity in males. This hypothesis is the subject of several clinical trials of anti-androgen therapies around the world. Here, we investigated the sex-associated TMPRSS2 and ACE2 expression in human and mouse lungs and interrogated the possibility of pharmacologic modification of their expression with anti-androgens. We found no evidence for increased TMPRSS2 expression in the lungs of males compared to females in humans or mice. Furthermore, in male mice, treatment with the androgen receptor antagonist enzalutamide did not decrease pulmonary TMPRSS2. On the other hand, ACE2 and AR expression was sexually dimorphic and higher in males than females. ACE2 was moderately suppressible with enzalutamide administration. Our work suggests that sex differences in COVID-19 outcomes attributable to viral entry are independent of TMPRSS2. Modest changes in ACE2 could account for some of the sex discordance.Item Building on the essential foundation of physiology(Wiley, 2020-10) Ren, Clement L.; Gaston, Benjamin; Pediatrics, School of MedicineItem d-Cystine di(m)ethyl ester reverses the deleterious effects of morphine on ventilation and arterial blood gas chemistry while promoting antinociception(Springer Nature, 2021-05-11) Gaston, Benjamin; Baby, Santhosh M.; May, Walter J.; Young, Alex P.; Grossfield, Alan; Bates, James N.; Seckler, James M.; Wilson, Christopher G.; Lewis, Stephen J.; Pediatrics, School of MedicineWe have identified thiolesters that reverse the negative effects of opioids on breathing without compromising antinociception. Here we report the effects of d-cystine diethyl ester (d-cystine diEE) or d-cystine dimethyl ester (d-cystine diME) on morphine-induced changes in ventilation, arterial-blood gas chemistry, A-a gradient (index of gas-exchange in the lungs) and antinociception in freely moving rats. Injection of morphine (10 mg/kg, IV) elicited negative effects on breathing (e.g., depression of tidal volume, minute ventilation, peak inspiratory flow, and inspiratory drive). Subsequent injection of d-cystine diEE (500 μmol/kg, IV) elicited an immediate and sustained reversal of these effects of morphine. Injection of morphine (10 mg/kg, IV) also elicited pronounced decreases in arterial blood pH, pO2 and sO2 accompanied by pronounced increases in pCO2 (all indicative of a decrease in ventilatory drive) and A-a gradient (mismatch in ventilation-perfusion in the lungs). These effects of morphine were reversed in an immediate and sustained fashion by d-cystine diME (500 μmol/kg, IV). Finally, the duration of morphine (5 and 10 mg/kg, IV) antinociception was augmented by d-cystine diEE. d-cystine diEE and d-cystine diME may be clinically useful agents that can effectively reverse the negative effects of morphine on breathing and gas-exchange in the lungs while promoting antinociception. Our study suggests that the d-cystine thiolesters are able to differentially modulate the intracellular signaling cascades that mediate morphine-induced ventilatory depression as opposed to those that mediate morphine-induced antinociception and sedation.Item Genetic analyses identify GSDMB associated with asthma severity, exacerbations, and antiviral pathways(Elsevier, 2020) Li, Xingnan; Christenson, Stephanie A.; Modena, Brian; Li, Huashi; Busse, William W.; Castro, Mario; Denlinger, Loren C.; Erzurum, Serpil C.; Fahy, John V.; Gaston, Benjamin; Hastie, Annette T.; Israel, Elliot; Jarjour, Nizar N.; Levy, Bruce D.; Moore, Wendy C.; Woodruff, Prescott G.; Kaminski, Naftali; Wenzel, Sally E.; Bleecker, Eugene R.; Meyers, Deborah A.; Pediatrics, School of MedicineBackground The Chr17q12-21.2 region is the strongest and most consistently associated region with asthma susceptibility. The functional genes or single nucleotide polymorphisms (SNPs) are not obvious due to linkage disequilibrium. Objectives We sought to comprehensively investigate whole-genome sequence and RNA sequence from human bronchial epithelial cells to dissect functional genes/SNPs for asthma severity in the Severe Asthma Research Program. Methods Expression quantitative trait loci analysis (n = 114), correlation analysis (n = 156) of gene expression and asthma phenotypes, and pathway analysis were performed in bronchial epithelial cells and replicated. Genetic association for asthma severity (426 severe vs 531 nonsevere asthma) and longitudinal asthma exacerbations (n = 273) was performed. Results Multiple SNPs in gasdermin B (GSDMB) associated with asthma severity (odds ratio, >1.25) and longitudinal asthma exacerbations (P < .05). Expression quantitative trait loci analyses identified multiple SNPs associated with expression levels of post-GPI attachment to proteins 3, GSDMB, or gasdermin A (3.1 × 10−9 < P < 1.8 × 10−4). Higher expression levels of GSDMB correlated with asthma and greater number of exacerbations (P < .05). Expression levels of GSDMB correlated with genes involved in IFN signaling, MHC class I antigen presentation, and immune system pathways (false-discovery rate–adjusted P < .05). rs1031458 and rs3902920 in GSDMB colocalized with IFN regulatory factor binding sites and associated with GSDMB expression, asthma severity, and asthma exacerbations (P < .05). Conclusions By using a unique set of gene expression data from lung cells obtained using bronchoscopy from comprehensively characterized subjects with asthma, we show that SNPs in GSDMB associated with asthma severity, exacerbations, and GSDMB expression levels. Furthermore, its expression levels correlated with asthma exacerbations and antiviral pathways. Thus, GSDMB is a functional gene for both asthma susceptibility and severity.Item HSD3B1 genotype identifies glucocorticoid responsiveness in severe asthma(National Academy of Sciences, 2020-01-28) Zein, Joe; Gaston, Benjamin; Bazeley, Peter; DeBoer, Mark D.; Igo, Robert P., Jr; Bleecker, Eugene R.; Meyers, Deborah; Comhair, Suzy; Marozkina, Nadzeya V.; Cotton, Calvin; Patel, Mona; Alyamani, Mohammad; Xu, Weiling; Busse, William W.; Calhoun, William J.; Ortega, Victor; Hawkins, Gregory A.; Castro, Mario; Chung, Kian Fan; Fahy, John V.; Fitzpatrick, Anne M.; Israel, Elliot; Jarjour, Nizar N.; Levy, Bruce; Mauger, David T.; Moore, Wendy C.; Noel, Patricia; Peters, Stephen P.; Teague, W. Gerald; Wenzel, Sally E.; Erzurum, Serpil C.; Sharifi, Nima; Medicine, School of MedicineAsthma resistance to glucocorticoid treatment is a major health problem with unclear etiology. Glucocorticoids inhibit adrenal androgen production. However, androgens have potential benefits in asthma. HSD3B1 encodes for 3β-hydroxysteroid dehydrogenase-1 (3β-HSD1), which catalyzes peripheral conversion from adrenal dehydroepiandrosterone (DHEA) to potent androgens and has a germline missense-encoding polymorphism. The adrenal restrictive HSD3B1(1245A) allele limits conversion, whereas the adrenal permissive HSD3B1(1245C) allele increases DHEA metabolism to potent androgens. In the Severe Asthma Research Program (SARP) III cohort, we determined the association between DHEA-sulfate and percentage predicted forced expiratory volume in 1 s (FEV1PP). HSD3B1(1245) genotypes were assessed, and association between adrenal restrictive and adrenal permissive alleles and FEV1PP in patients with (GC) and without (noGC) daily oral glucocorticoid treatment was determined (n = 318). Validation was performed in a second cohort (SARP I&II; n = 184). DHEA-sulfate is associated with FEV1PP and is suppressed with GC treatment. GC patients homozygous for the adrenal restrictive genotype have lower FEV1PP compared with noGC patients (54.3% vs. 75.1%; P < 0.001). In patients with the homozygous adrenal permissive genotype, there was no FEV1PP difference in GC vs. noGC patients (73.4% vs. 78.9%; P = 0.39). Results were independently confirmed: FEV1PP for homozygous adrenal restrictive genotype in GC vs. noGC is 49.8 vs. 63.4 (P < 0.001), and for homozygous adrenal permissive genotype, it is 66.7 vs. 67.7 (P = 0.92). The adrenal restrictive HSD3B1(1245) genotype is associated with GC resistance. This effect appears to be driven by GC suppression of 3β-HSD1 substrate. Our results suggest opportunities for prediction of GC resistance and pharmacologic intervention.Item A pilot study on the kinetics of metabolites and microvascular cutaneous effects of nitric oxide inhalation in healthy volunteers(PLOS, 2019-08-30) Tonelli, Adriano R.; Aulak, Kulwant S.; Ahmed, Mostafa K.; Hausladen, Alfred; Abuhalimeh, Batool; Casa, Charlie J.; Rogers, Stephen C.; Timm, David; Doctor, Allan; Gaston, Benjamin; Dweik, Raed A.; Pediatrics, School of MedicineRATIONALE: Inhaled nitric oxide (NO) exerts a variety of effects through metabolites and these play an important role in regulation of hemodynamics in the body. A detailed investigation into the generation of these metabolites has been overlooked. OBJECTIVES: We investigated the kinetics of nitrite and S-nitrosothiol-hemoglobin (SNO-Hb) in plasma derived from inhaled NO subjects and how this modifies the cutaneous microvascular response. FINDINGS: We enrolled 15 healthy volunteers. Plasma nitrite levels at baseline and during NO inhalation (15 minutes at 40 ppm) were 102 (86-118) and 114 (87-129) nM, respectively. The nitrite peak occurred at 5 minutes of discontinuing NO (131 (104-170) nM). Plasma nitrate levels were not significantly different during the study. SNO-Hb molar ratio levels at baseline and during NO inhalation were 4.7E-3 (2.5E-3-5.8E-3) and 7.8E-3 (4.1E-3-13.0E-3), respectively. Levels of SNO-Hb continued to climb up to the last study time point (30 min: 10.6E-3 (5.3E-3-15.5E-3)). The response to acetylcholine iontophoresis both before and during NO inhalation was inversely associated with the SNO-Hb level (r: -0.57, p = 0.03, and r: -0.54, p = 0.04, respectively). CONCLUSIONS: Both nitrite and SNO-Hb increase during NO inhalation. Nitrite increases first, followed by a more sustained increase in Hb-SNO. Nitrite and Hb-SNO could be a mobile reservoir of NO with potential implications on the systemic microvasculature.Item The Precision Interventions for Severe and/or Exacerbation-Prone (PrecISE) Asthma Network: an overview of Network organization, procedures and interventions(Elsevier, 2022-02) Georas, Steve N.; Wright, Rosalind J.; Ivanova, Anastasia; Israel, Elliot; LaVange, Lisa M.; Akuthota, Praveen; Carr, Tara F.; Denlinger, Loren C.; Fajt, Merritt L.; Kumar, Rajesh; O’Neal, Wanda K.; Phipatanakul, Wanda; Szefler, Stanley J.; Aronica, Mark A.; Bacharier, Leonard B.; Burbank, Allison J.; Castro, Mario; Alexander, Laura Crotty; Bamdad, Julie; Cardet, Juan Carlos; Comhair, Suzy A. A.; Covar, Ronina A.; DiMango, Emily A.; Erwin, Kim; Erzurum, Serpil C.; Fahy, John V.; Gaffin, Jonathan M.; Gaston, Benjamin; Gerald, Lynn B.; Hoffman, Eric A.; Holguin, Fernando; Jackson, Daniel J.; James, John; Jarjour, Nizar N.; Kenyon, Nicholas J.; Khatri, Sumita; Kirwan, John P.; Kraft, Monica; Krishnan, Jerry A.; Liu, Andrew H.; Liu, Mark C.; Marquis, M. Alison; Martinez, Fernando; Mey, Jacob; Moore, Wendy C.; Moy, James N.; Ortega, Victor E.; Peden, David B.; Pennington, Emily; Peters, Michael C.; Ross, Kristie; Sanchez, Maria; Smith, Lewis J.; Sorkness, Ronald L.; Wechsler, Michael E.; Wenzel, Sally E.; White, Steven R.; Zein, Joe; Zeki, Amir A.; Noel, Patricia; Pediatrics, School of MedicineAsthma is a heterogeneous disease, with multiple underlying inflammatory pathways and structural airway abnormalities that impact disease persistence and severity. Recent progress has been made in developing targeted asthma therapeutics, especially for subjects with eosinophilic asthma. However, there is an unmet need for new approaches to treat patients with severe and exacerbation prone asthma, who contribute disproportionately to disease burden. Extensive deep phenotyping has revealed the heterogeneous nature of severe asthma and identified distinct disease subtypes. A current challenge in the field is to translate new and emerging knowledge about different pathobiologic mechanisms in asthma into patient-specific therapies, with the ultimate goal of modifying the natural history of disease. Here we describe the Precision Interventions for Severe and/or Exacerbation Prone Asthma (PrecISE) Network, a groundbreaking collaborative effort of asthma researchers and biostatisticians from around the U.S. The PrecISE Network was designed to conduct phase II/proof of concept clinical trials of precision interventions in the severe asthma population, and is supported by the National Heart Lung and Blood Institute of the National Institutes of Health. Using an innovative adaptive platform trial design, the Network will evaluate up to six interventions simultaneously in biomarker-defined subgroups of subjects. We review the development and organizational structure of the Network, and choice of interventions being studied. We hope that the PrecISE Network will enhance our understanding of asthma subtypes and accelerate the development of therapeutics for of severe asthma.Item Respiratory Distress in the Newborn with Primary Ciliary Dyskinesia(MDPI, 2021-02-18) Machogu, Evans; Gaston, Benjamin; Pediatrics, School of MedicinePrimary ciliary dyskinesia (PCD) is inherited in a predominantly autosomal recessive manner with over 45 currently identified causative genes. It is a clinically heterogeneous disorder that results in a chronic wet cough and drainage from the paranasal sinuses, chronic otitis media with hearing impairment as well as male infertility. Approximately 50% of patients have situs inversus totalis. Prior to the development of chronic oto-sino-pulmonary symptoms, neonatal respiratory distress occurs in more than 80% of patients as a result of impaired mucociliary clearance and mucus impaction causing atelectasis and lobar collapse. Diagnosis is often delayed due to overlapping symptoms with other causes of neonatal respiratory distress. A work up for PCD should be initiated in the newborn with compatible clinical features, especially those with respiratory distress, consistent radiographic findings or persistent oxygen requirement and/or organ laterality defects.Item A Treatment to Eliminate SARS-CoV-2 Replication in Human Airway Epithelial Cells Is Safe for Inhalation as an Aerosol in Healthy Human Subjects(American Association for Respiratory Care (AARC), 2020-09-21) Davis, Michael D.; Clemente, Tatiana M.; Giddings, Olivia K.; Ross, Kristie; Cunningham, Rebekah S.; Smith, Laura; Simpson, Edward; Liu, Yunlong; Kloepfer, Kirsten; Ramsey, I. Scott; Zhao, Yi; Robinson, Christopher M.; Gilk, Stacey D.; Gaston, Benjamin; Pediatrics, School of MedicineBackground: Low airway surface pH is associated with many airway diseases, impairs antimicrobial host defense and worsens airway inflammation. Inhaled Optate is designed to safely to raise airway surface pH and is well-tolerated in humans. Raising intracellular pH partially prevents activation of SARS-CoV-2 in primary normal human airway epithelial (NHAE) cells, decreasing viral replication by several mechanisms. Methods: Here, we grew primary normal human airway epithelial (NHAE) cells from healthy subjects, infected them with SARS-CoV-2 (isolate USA-WA1/2020), and used clinical Optate at concentrations used in humans in vivo to determine whether it would prevent viral infection and replication. Cells were pre-treated with Optate or placebo prior to infection (MOI of 0.1) and viral replication was determined by plaque assay and nucleocapsid (N) protein levels. Healthy human subjects also inhaled Optate as part of a Phase 2a safety trial. Results: Optate almost completely prevented viral replication at each time point between 24 and 120 hours, relative to placebo, both by plaque assay and by N protein expression (p < 0.001). Mechanistically, Optate inhibited expression of major endosomal trafficking genes and raised NHAE intracellular pH. Optate had no effect on NHAE cell viability at any time point. Inhaled Optate was well tolerated in 10 normal subjects, with no change in lung function, vital signs or oxygenation. Conclusions: Inhaled Optate may be well-suited for a clinical trial in patients with a pulmonary SARS-CoV-2 infection. However, it is vitally important for patient safety that formulations designed for inhalation with regards to pH, isotonicity and osmolality be used. An inhalational treatment that safely prevents SARS-CoV-2 viral replication could be helpful for treating patients with pulmonary SARS-CoV-2 infection.Item An Update on Thiol Signaling: S-Nitrosothiols, Hydrogen Sulfide and a Putative Role for Thionitrous Acid(MDPI, 2020-03) Marozkina, Nadzeya; Gaston, Benjamin; Medicine, School of MedicineLong considered vital to antioxidant defenses, thiol chemistry has more recently been recognized to be of fundamental importance to cell signaling. S-nitrosothiols-such as S-nitrosoglutathione (GSNO)-and hydrogen sulfide (H2S) are physiologic signaling thiols that are regulated enzymatically. Current evidence suggests that they modify target protein function primarily through post-translational modifications. GSNO is made by NOS and other metalloproteins; H2S by metabolism of cysteine, homocysteine and cystathionine precursors. GSNO generally acts independently of NO generation and has a variety of gene regulatory, immune modulator, vascular, respiratory and neuronal effects. Some of this physiology is shared with H2S, though the mechanisms differ. Recent evidence also suggests that molecules resulting from reactions between GSNO and H2S, such as thionitrous acid (HSNO), could also have a role in physiology. Taken together, these data suggest important new potential targets for thiol-based drug development.