Clinical Medicine
Abstract
BACKGROUND. Idiopathic intracranial hypertension (IIH) is a condition predominantly affecting obese women of reproductive age. Recent evidence suggests that IIH is a disease of metabolic dysregulation, androgen excess and an increased risk of cardiovascular morbidity. Here we evaluate systemic and adipose specific metabolic determinants of the IIH phenotype. METHODS. In fasted, matched IIH (N=97) and control (N=43) patients, we assessed: glucose and insulin homeostasis and leptin levels. Body composition was assessed along with an interrogation of adipose tissue function via nuclear magnetic resonance metabolomics and RNA sequencing in paired omental and subcutaneous biopsies in a case control study. RESULTS. We demonstrate an insulin and leptin resistant phenotype in IIH in excess to that driven by obesity. Adiposity in IIH is preferentially centripetal and is associated with increased disease activity and insulin resistance. IIH adipocytes appear transcriptionally and metabolically primed towards depot-specific lipogenesis. CONCLUSIONS. These data show that IIH is a metabolic disorder in which adipose tissue dysfunction is a feature of the disease. Managing IIH as a metabolic disease could reduce disease morbidity and improving cardiovascular outcomes. FUNDING. This study was supported by the National Institute of Health Research UK (NIHR-CS-011-028), the Medical Research Council UK (MR/K015184/1) and the Midlands Neuroscience Teaching and Research Fund.
Authors
Connar S.J. Westgate, Hannah F. Botfield, Zerin Alimajstorovic, Andreas Yiangou, Mark Walsh, Gabrielle Smith, Rishi Singhal, James L. Mitchell, Olivia Grech, Keira A. Markey, Daniel Hebenstreit, Daniel A. Tennant, Jeremy W. Tomlinson, Susan P. Mollan, Christian Ludwig, Ildem Akerman, Gareth G. Lavery, Alexandra J. Sinclair
Abstract
BACKGROUND. Methodology for estimation of cerebrospinal fluid (CSF) tracer clearance could have wide clinical application in predicting excretion of intrathecal drugs and metabolic solutes from brain metabolism, and for diagnostic work-up of cerebrospinal fluid disturbances. METHODS. The magnetic resonance imaging (MRI) contrast agent gadobutrol (Gadovist) was utilized as CSF tracer and injected into the lumbar CSF. Gadobutrol is contained outside blood vessels of the central nervous system (CNS) and is thus eliminated along extra-vascular pathways, analogous to many CNS metabolites and intrathecal drugs. Tracer enrichment was verified and assessed in CSF by MRI at level of the cisterna magna in parallel with obtaining blood samples through 48 hours. RESULTS. In a reference patient cohort (REF; n=29), both enrichment within CSF and blood coincided in time. Blood concentration profiles of gadobutrol through 48 hours varied between patients diagnosed with CSF leakage (n=4), idiopathic normal pressure hydrocephalus dementia (iNPH; n=7), pineal cysts (n=8), and idiopathic intracranial hypertension (IIH; n=4). CONCLUSION. Assessment of CSF tracer clearance is clinically feasible and may provide a way to predict extra-vascular clearance of intrathecal drugs and endogenous metabolites from the CNS. The peak concentration in blood (at about 10 hrs) preceded by far peak tracer enhancement at MRI in extra-cranial lymphatic structures (at about 24 hrs) as shown in previous studies, indicating a major role of the spinal canal in CSF clearance capacity. FUNDING. The work was supported by Department of Neurosurgery, Oslo university hospital, and Norwegian Institute for Air Research, Kjeller, Norway, and University of Oslo.
Authors
Per K. Eide, Espen Mariussen, Hilde Uggerud, Are H. Pripp, Aslan Lashkarivand, Bjørnar Hassel, Hege Christensen, Markus Herberg Hovd, Geir Ringstad
Abstract
Background: COVID-19 is more benign in children compared to adults for unknown reasons. This contrasts with other respiratory viruses where disease manifestations are often more severe in children. We hypothesize that a more robust early innate immune response to SARS-CoV-2 protects against severe disease. Methods: Clinical outcomes, SARS-CoV-2 viral copies and cellular gene expression were compared in nasopharyngeal swabs obtained at the time of presentation to the Emergency Department from 12 children and 27 adults using bulk RNA sequencing and quantitative reverse transcription PCR. Total protein, cytokines and anti-SARS-CoV-2 IgG and IgA were quantified in nasal fluid. Results: SARS-CoV-2 copies, ACE2 and TMPRSS2 gene expression were similar in children and adults, but children displayed higher expression of genes associated with interferon signaling, NLRP3 inflammasome, and other innate pathways. Higher levels of IFN-α2, IFN-γ, IP-10, IL-8, and IL-1β protein were detected in nasal fluid in children versus adults. Children also expressed higher levels of genes associated with immune cells whereas expression of those associated with epithelial cells did not differ in children versus adults. Anti-SARS-CoV-2 IgA and IgG were detected at similar levels in nasal fluid from both groups. None of the children required supplemental oxygen whereas 7 adults did (p=0.03); four adults died. Conclusions: These findings provide direct evidence of a more vigorous early mucosal immune response in children compared to adults and suggest that this contributes to favorable clinical outcomes.
Authors
Carl A. Pierce, Sharlene Sy, Benjamin Galen, Doctor Y. Goldstein, Erika P. Orner, Marla J. Keller, Kevan C. Herold, Betsy C. Herold
Abstract
Background and aims: Pancreatic cancer is one of the deadliest cancers, still with low long term survival rates. Despite recent advances in treatment, it is extremely important to screen high-risk individuals in order to establish preventive and early detection measures and, in some cases, molecular driven therapeutic options. Familial pancreatic cancer (FPC) accounts for 4%-10% of pancreatic cancers. Several germline mutations are known to be related with an increased risk and might offer novel screening and therapy options. In this study, our goal was to discover the identity of a familial pancreatic cancer gene in two members of a family with FPC. Methods: Whole exome sequencing and PCR confirmation was performed on the surgical specimen and peripheral blood of an index patient and her sister in a family with high incidence of pancreatic cancer, to identify somatic and germline mutations associated with familial pancreatic cancer. Compartment-specific gene expression data and immunohistochemistry was used to characterize PALLD expression. Results: A germline mutation of the PALLD gene (NM_001166108.1:c.G154A:p.D52N) was detected in the index patient with pancreatic cancer. The identical PALLD mutation was identified in the tumor tissue of her sister. Whole genome sequencing showed similar somatic mutation patterns between the two sisters. Apart from the PALLD mutation, commonly mutated genes that characterize PDAC (KRAS and CDKN2A) were found in both tumor samples. However, the two patients harbored different somatic KRAS mutations (respectively G12D in the index patient and G12V in the index patient’s sister). Analysis for PALLD mutation in the healthy siblings of the two sisters was negative, indicating that the identified PALLD mutation might have a disease specific impact. Of note, compartment-specific gene expression data and IHC suggested a predominant role in cancer associated fibroblasts (CAFs). Conclusion: We identified a germline mutation of the palladin (PALLD) gene in two siblings in Europe, affected by familial pancreatic cancer, with a predominant function in the tumor stroma.
Authors
Lucia Liotta, Sebastian Lange, H. Carlo Maurer, Kenneth P. Olive, Rickmer Braren, Nicole Pfarr, Alexander Muckenhuber, Moritz Jesinghaus, Wilko Weichert, Katja Steiger, Sebastian Burger, Helmut Friess, Roland M. Schmid, Hana Alguel, Philipp Jost, Juliane Ramser, Christine Fischer, Anne S. Quante, Maximilian Reichert, Michael Quante
Abstract
Background: Estimates of seroprevalence to SARS-CoV-2 vary widely and may influence vaccination response. We ascertained IgG levels across a single US metropolitan site, Chicago, from June 2020 through December 2020. Methods: Participants (n=7935) were recruited through electronic advertising and received materials for a self-sampled dried blood spot assay through the mail or a minimal contact in person method. IgG to the receptor binding domain of SARS-CoV-2 was measured using an established highly sensitive and highly specific assay. Results: Overall seroprevalence was 17.9%, with no significant difference between method of contact. Only 2.5% of participants reported having had a diagnosis of COVID-19 based on virus detection, consistent with a 7-fold greater exposure to SARS-CoV-2 measured by serology than detected by viral testing. The range of IgG level observed in seropositive participants from this community survey overlapped with the range of IgG levels associated with COVID-19 cases having a documented positive PCR positive test. From a subset of those who participated in repeat testing, half of seropositive individuals retained detectable antibodies for 3-4 months. Conclusions: Quantitative IgG measurements with a highly specific and sensitive assay indicate more widespread exposure to SARS-CoV-2 than observed by viral testing. The range of IgG concentration produced from these asymptomatic exposures is similar to IgG levels occurring after documented non-hospitalized COVID-19, which is considerably lower than that produced from hospitalized COVID-19 cases. The differing ranges of IgG response, coupled with the rate of decay of antibodies, may influence response to subsequent viral exposure and vaccine.
Authors
Alexis R. Demonbreun, Thomas W. McDade, Lorenzo L. Pesce, Lauren A. Vaught, Nina L. Reiser, Elena Bogdanovic, Matthew P. Velez, Ryan R. Hsieh, Lacy M. Simons, Rana Saber, Daniel T. Ryan, Michael G. Ison, Judd F. Hultquist, John T. Wilkins, Richard T. D'Aquila, Brian Mustanski, Elizabeth M. McNally
Abstract
Introduction: Coronavirus 2019 (COVID-19) clinical course is heterogeneous, ranging from mild to severe multi-organ failure and death. In this study, we analyzed cell-free DNA (cfDNA) as a biomarker of injury to define the sources of tissue injury that contribute to such different trajectories. Methods: We conducted a multi-center prospective cohort study to enroll COVID-19 patients and collect plasma samples. Plasma cfDNA was subject to bisulfite sequencing. A library of tissue-specific DNA methylation signatures was used to analyze sequence reads to quantitate cfDNA from different tissue types. We then determined the correlation of tissue-specific cfDNA measures to COVID-19 outcomes. Similar analyses was performed for healthy controls and a comparator group of patients with respiratory syncytial virus and influenza. Results: We found markedly elevated levels and divergent tissue sources of cfDNA in COVID-19 patients compared to influenza and respiratory syncytial virus patients or healthy controls. The major sources of cfDNA in COVID-19 were hematopoietic cells, vascular endothelium, hepatocyte, adipocyte, kidney, heart and lung. cfDNA levels positively correlated with COVID-19 disease severity, c reactive protein, D-Dimer. cfDNA profile at admission identified patients who subsequently required intensive care or died during hospitalization. Furthermore, the increased cfDNA in COVID-19 patients generates excessive mitochondrial reactive oxygen species (mtROS) in renal tubular cells in a concentration-dependent manner. This mtROS production was inhibited by a toll-like receptor 9 (TLR-9)-specific antagonist. Conclusion cfDNA maps tissue injury that predict COVID-19 outcomes, and may mechanistically propagates COVID-19 induced tissue injury. Funding sources: Intramural Targeted Anti-COVID-19 grant, National Institutes of Health
Authors
Temesgen E. Andargie, Naoko Tsuji, Fayaz Seifuddin, Moon Kyoo Jang, Peter S.T. Yuen, Hyesik Kong, Ilker Tunc, Komudi Singh, Ananth Charya, Kenneth J. Wilkins, Steven D. Nathan, Andrea L. Cox, Mehdi Pirooznia, Robert A. Star, Sean Agbor-Enoh
Abstract
BACKGROUND Metabolic flexibility (MF) refers to the relative ability to utilize lipid and carbohydrate substrates and to transition between them. It is not clear whether MF is impaired in obese youth and what the determining factors are.METHODS We investigated the determinants of MF (increased respiratory exchange ratio [ΔRER] under insulin-stimulated conditions) in pubertal youth (n = 104; 15.6 ± 1.8 years) with obesity across the spectrum of glucose tolerance compared with normal weight (NW) controls, including body composition (fat-free mass [FFM], %body fat), visceral adipose fat (VAT) (MRI), glycemia, and insulin sensitivity (IS) [3-hour hyperinsulinemic-euglycemic clamp with measurement of lipolysis ([2H5] glycerol), free fatty acids (FFAs), and RER (indirect calorimetry)].RESULTS Youth with prediabetes and type 2 diabetes had lower ΔRER and oxidative and nonoxidative glucose disposal compared with NW, with no significant difference in ΔRER between NW and obese with normal glucose tolerance. In multiple regression analysis, ISFFM (β = 0.4, P = 0.004), percentage suppression of FFAs (r = 0.26, P = 0.007), and race/ethnicity (β = –0.23, P = 0.02) contributed to the variance in ΔRER (R2 = 0.30, P < 0.001) independent of percentage body fat (or VAT), sex, Tanner stage, and hemoglobin A1c.Conclusion MF is defective at the extreme of the metabolic phenotype in obese youth with dysglycemia related to a defect in IS limiting substrate utilization.FUNDING USDA/ARS Project Number 3092-51000-057.
Authors
Fida Bacha, Sara Klinepeter Bartz, Maurice Puyau, Anne Adolph, Susan Sharma
Abstract
BACKGROUND. Beige and brown adipose tissue (BAT) are associated with improved metabolic homeostasis. We recently reported that the β3AR agonist mirabegron induced beige adipose tissue in obese insulin resistant subjects, and this was accompanied by improved glucose metabolism. Here, we evaluated whether pioglitazone treatment, or the combination pioglitazone and mirabegron treatment, was more effective at inducing beige adipose or BAT than mirabegron treatment alone. Both drugs were used at FDA-approved dosages. METHODS. We measured BAT by PET CT scans, beige adipose tissue by immunohistochemistry, and comprehensively characterized glucose and lipid homeostasis and insulin sensitivity by euglycemic clamp and oral glucose tolerance tests. Subcutaneous white adipose tissue, muscle fiber type composition and capillary density, lipotoxicity, and systemic inflammation were evaluated by immunohistochemistry, gene expression profiling, mass spectroscopy, and ELISAs. RESULTS. Treatment with pioglitazone or the combination of pioglitazone and mirabegron increased beige adipose tissue protein marker expression and improved insulin sensitivity and glucose homeostasis, but neither treatment induced BAT in these obese subjects. When the magnitude of the responses to the treatments were evaluated, mirabegron was found to be the most effective at inducing beige adipose tissue. Although monotherapy with either mirabegron or pioglitazone induced adipose beiging, combination treatment resulted in less beiging than either alone. The three treatments also had different effects on muscle fiber type switching and capillary density. CONCLUSION. The addition of pioglitazone to mirabegron treatment does not enhance beiging or increase BAT in obese, insulin-resistant research participants. TRIAL REGISTRATION. Clinicaltrials.gov NCT02919176. FUNDING. NIH: DK112282, P20GM103527, and CTSA grant UL1TR001998.
Authors
Brian S. Finlin, Hasiyet Memetimin, Beibei Zhu, Amy L. Confides, Hemendra J. Vekaria, Riham H. El Khouli, Zachary R. Johnson, Philip M. Westgate, Jianzhong Chen, Andrew J. Morris, Patrick G. Sullivan, Esther E. Dupont-Versteegden, Philip A. Kern
Abstract
BACKGROUND. Type 1 diabetes (T1D) is a risk factor for dementia and structural brain changes. It remains to be determined whether transient insulin deprivation that frequently occurs in insulin treated T1D individual alters brain function. METHODS. We therefore, performed functional and structural magnetic resonance imaging, magnetic resonance spectroscopy, and neuropsychological testing at baseline and following 5.4 ± 0.6 hours of insulin deprivation in 14 T1D and compared to 14 age-, sex-, and body mass index–matched, nondiabetic (ND) participants with no interventions. RESULTS. Insulin deprivation in T1D increased blood glucose, and β-hydroxybutyrate, while reducing bicarbonate levels. T1D participants showed lower baseline brain N-acetyl aspartate and myo-inositol levels but higher cortical fractional anisotropy, suggesting unhealthy neurons and brain microstructure. Although cognitive functions did not differ between T1D and ND at baseline, significant changes in fine motor speed as well as attention and short-term memory occurred following insulin deprivation in T1D participants. Insulin deprivation also reduced brain adenosine triphosphate levels and altered phosphocreatine/ adenosine triphosphate ratio. Baseline differences in functional connectivity in brain regions between T1D and ND were noted and on insulin deprivation further alterations in functional connectivity between regions especially cortical and hippocampus-caudate regions were observed. These alterations in functional connectivity correlated to brain metabolites and to changes in cognition. CONCLUSIONS. Transient insulin deprivation thus, caused alterations in executive aspects of cognitive function concurrent with functional connectivity between memory regions and the sensory cortex. These findings have important clinical implications as many patients with T1D inadvertently have periods of transient insulin deprivation. TRIAL REGISTRATION NUMBER. NCT03392441
Authors
Ana L. Creo, Tiffany M. Cortes, Hang Joon Jo, Andrea R.S. Huebner, Surendra Dasari, Jan-Mendelt Tillema, Aida N. Lteif, Katherine A. Klaus, Gregory N. Ruegsegger, Yogish C. Kudva, Ronald C. Petersen, John D. Port, K. Sreekumaran Nair
Abstract
BACKGROUND Recessive dystrophic epidermolysis bullosa (RDEB) is an incurable disease that causes severe mucocutaneous fragility due to mutations in COL7A1 (encoding type VII collagen [C7]). In this phase I/IIa trial, we evaluated the safety and possible clinical efficacy of intravenous infusion of allogeneic human umbilical cord blood–derived mesenchymal stem cells (hUCB-MSCs) in patients with RDEB.METHODS Four adult and two pediatric patients with RDEB were treated with 3 intravenous injections of hUCB-MSCs (1 × 106 to 3 × 106 cells/kg) every 2 weeks and followed up for 8–24 months after treatment. The primary endpoint was safety. Secondary endpoints related to efficacy included clinical parameters, such as disease severity score, wound assessment, itch and pain score, and quality of life. C7 expression levels and inflammatory infiltrates in the skin, as well as serum levels of inflammatory markers and neuropeptides, were also assessed.RESULTS Intravenous hUCB-MSC infusions were well tolerated, without serious adverse events. Improvements in the Birmingham Epidermolysis Bullosa Severity Score, body surface area involvement, blister counts, pain, pruritus, and quality of life were observed with maximal effects at 56–112 days after treatment. hUCB-MSC administration induced M2 macrophage polarization and reduced mast cell infiltration in RDEB skin. Serum levels of substance P were decreased after therapy. Increased C7 expression was observed at the dermoepidermal junction in 1 of 6 patients at day 56.CONCLUSION To the best of our knowledge, this is the first clinical trial of systemic administration of allogeneic hUCB-MSCs in patients with RDEB, demonstrating safety and transient clinical benefits.TRIAL REGISTRATION ClinicalTrials.gov NCT04520022.FUNDING This work was supported by Daewoong Pharmaceutical Co. Ltd. and Kangstem Biotech Co. Ltd.
Authors
Sang Eun Lee, Seung-Ju Lee, Song-Ee Kim, Kinam Kim, Boyoung Cho, Kyounghwan Roh, Soo-Chan Kim
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