bluuebunny/crossref_metadata_2025_split huggingface dataset:
Physiologically Based Pharmacokinetic (PBPK) Modelling to Predict Breast Milk Exposure of Valproic Acid
Authors: Nauwelaerts Nina , Bouillon Thomas , Deferm Neel , Lammens Bart , Annaert Pieter 
Published: May 2022

Breastfeeding has many positive effects on the health and well‐being of mother and baby. During lactation, a pharmacological therapy may be required. Currently there is a knowledge gap regarding the safety of medicines during lactation, which may lead to unnecessary cessation of breastfeeding or incur unknown risks to the child when continuing breastfeeding while on medication. The Innovative Medicines Initiative (IMI) ConcePTION aims to address this and other issues related to medication use during pregnancy and lactation.The objective of this study performed in the IMI ConcePTION framework was to explore the utility of Physiologically‐Based Pharmacokinetic (PBPK) modelling in the generation of information regarding the safety of medicines (e.g. valproic acid, VPA) during breastfeeding.To achieve this goal, PK‐Sim® (v 9.1) (Open Systems Pharmacology) was used to first develop a reference PBPK model for VPA in adults using 7 training datasets. The median fold errors of the Area Under the Curve (AUC) and maximum plasma concentration (Cmax) for the 17 validation datasets were 0.89 (range: 0.74‐0.134) and 0.90 (range: 0.60‐1.36), indicating a good predictive performance. In a next step, this PBPK model was extended with a breast compartment (including a subcompartment representing the breast milk) according to the work from Dallmann et al. (2018). Transfer of medicines between the milk and the intracellular compartment was parametrized with a clearance for secretion to milk (Clsec), and a clearance for reuptake (Clre). These clearance values were determined based on physicochemical properties using the empirical model from Koshimichi et al. (2011). Clsec and Clre were 235.05 and 1452.78 mL/h. The PBPK model for lactating women was used to predict exposure of VPA in plasma and human breast milk. The simulated milk‐to‐plasma (M/P) ratio was 0.016, similar to reported M/P ratio’s (range: 0.007‐0.25). Finally, the daily infant dose was calculated based on the simulated concentration in the milk and used as input for an infant PBPK model. The relative infant dose was 1.4 %. Average steady‐state infant plasma concentration was estimated to be 0.83 mg/L (relative infant exposure: 1.2 %), compared to a wide range of observations starting from undetectable concentrations up to 41 mg/L.PBPK modelling was successfully used to predict the transfer of VPA into the human breast milk, and to estimate subsequent infant exposure via breastfeeding. Based on ongoing application to 11 other medicines, a generic workflow for PBPK‐based breast milk transfer of medicines has been developed. Current efforts to determine the in vitro permeability of VPA across the blood‐milk barrier may obviate the current need for (sparse) milk concentrations. This study illustrated the potential of PBPK modelling as a tool to fill the knowledge gap regarding the exposure to medicines in lactating women and their infants.
Transcriptional Characterization Suggests Accelerated Epithelial Differentiation in Trisomy 21 Lungs
Authors: Danopoulos Soula , Bhattacharya Soumyaroop , Cherry Caroline , Deutsch Gail , Mariani Thomas , Al Alam Denise 
Published: May 2022

RationaleDown Syndrome (DS), from trisomy 21 (T21), is the most common human chromosomal anomaly in the United States. Although DS can affect many organ systems, lung and heart disease are the leading causes of death. We recently reported that structural and molecular changes originate at the late pseudoglandular/early canalicular stages of development in T21 lungs. The initial, most striking, observation was dilatation of the terminal airways/acinar tubules. Thus, our goal was to better understand cellular heterogeneity at the transcriptional level that could be contributing to this phenotypic anomaly.MethodsSingle cell RNA sequencing (scRNAseq) was used to generate transcriptomic profiles of individual human lung cells in tissue obtained from T21 (n=5) and non‐T21 (n=4) prenatal lungs. Clustering, cluster marker identification, differential expression analysis, and UMAP representation was performed in Seurat. Cell populations were annotated using Toppfun. Spatial differences in cellular phenotypes were examined using immunofluorescent staining (IF) and fluorescent in situ hybridization (FISH).ResultsAll the major cell lineages were identified in both the T21 and non‐T21 lungs, with mesenchymal cells representing the largest fraction (63%), followed by epithelial (16%), immune (13%), and endothelial (8%) cells. Each cluster displayed a relatively equal distribution of cells between T21 and non‐T21 (Figure 1). Having previously observed structural changes in the airways, we focused on re‐clustering the epithelial cell population. This resulted in 12 different epithelial sub‐clusters, with 4 distal bud clusters analyzed separately. We noted differentially expressed genes within each epithelial sub‐cluster between the T21 and non‐T21 samples. 332 genes were significantly different in T21 in one or more cell clusters at FDR < 0.05. SOX2 expression was significantly down in two of the distal bud clusters, which was confirmed by IF. Additionally, immunohistochemical staining showed a trend for an increase in the number of SCGB1A1 and FOXJ1 positive cells within the proximal airways of T21 lungs as compared to non‐T21. Simultaneously, multiple distal epithelial sub‐populations demonstrated significant increases in gene expression associated with surfactant synthesis in T21, with pathway analysis displaying the activation of surfactant metabolism. Our sequencing data demonstrated differentially increased SFTPC within the AT2 and distal bud populations, which was confirmed by FISH.ConclusionOur data demonstrate that T21 is associated with increased expression of markers of differentiation in the prenatal lung, which may be an indication of accelerated epithelial cell differentiation.
Structure‐activity Relation of Halogenated 2,5‐Dimethoxyamphetamines Compared to their α‑Desmethyl (2C) Analogues
Authors: Rudin Deborah , Luethi Dino , Hoener Marius C. , Liechti Matthias E. 
Published: May 2022

Objective and hypothesis4‐Substituted derivatives of 2,5‐dimethoxyamphetamine (referred to as DOX derivatives) exhibit psychedelic and euphoria‐inducing effects, mainly mediated by 5‐HT2A receptor activation; for this reason, they are used recreationally but also bear therapeutic potential. Studies in humans and animals revealed that 4‐substitution with halogens results in high clinical potency, which increased with increasing size of the halogen. We therefore hypothesized that increasing size of the halogen substituent results in increased affinity at the 5‐HT2A receptor. Hence, we investigated the interaction profiles of 4‐halogenated DOX derivatives with monoaminergic receptors and transporters, and the trace amine‐associated receptor (TAAR) 1 and compared the obtained values to already known data of their α‐desmethyl (2C) analogues. This will lead to a better understanding of the structure‐activity relationship and potential side effects of these compounds, which could lead to novel and more efficacious drug candidates for drug‐assisted psychotherapy.MethodsWe assessed the binding affinity of 2,5‐dimethoxyamphetamine and its halogenated derivatives (DOF, DOC, DOB, and DOI) at several human serotonin (5‐HT) receptor subtypes, adrenergic and dopaminergic receptors, the trace amine‐associated receptor (TAAR) 1, and monoamine transporters. We determined the binding affinity by displacement of radioactively labeled ligands by the DOX derivatives by liquid scintillation counting in cell membrane preparations from cells transfected with the respective human receptor or transporter. Moreover, we investigated the activation potency of the DOX derivatives at the 5‐HT2A and 5‐HT2B receptor by calcium mobilization and at the TAAR1 by cAMP accumulation in cells transfected with the respective human receptor.ResultsThe 5‐HT2A receptor selectivity was substantially increased with increasing size of the halogen, with DOI displaying almost three orders of magnitude higher selectivity towards the 2A receptor subtype than DOF. All tested DOX derivatives were partial to full 5‐HT2A receptor agonists. The observed 5‐HT2 receptor interaction potency of the DOX derivatives is comparable to previously reported values of their 2C analogues, but with increased 5‐HT2A vs. 5‐HT1Aselectivity. None of the tested derivatives showed relevant affinity in the nanomolar range for TAAR1, α1A, α2A, D2, or monoamine transporters.ConclusionThe increased 5‐HT2A vs. 5‐HT1A selectivity of halogenated DOX derivatives compared to their 2C analogues may explain their increased clinical potency. However, increased 5‐HT2A vs. 5‐HT1A selectivity may also increase the risk of seizures. Hence, while DOX derivatives display advantages as 5‐HT2A‐selective compounds for pharmacological research, for clinical applications they may be inferior to 2C derivatives due to their potentially increased risks for seizures.
Determining Antibiotic and Anti‐cancer Potential of Small Compounds
Authors: Manning Maegan , Mowery Patricia 
Published: May 2022

Natural compounds are important leads for drug discovery. Staurosporine, which is produced by a Streptomyces species, has anti‐cancer properties but is too toxic for treatment. Analogs have been synthesized in the hopes of targeting cancer with less side effects.The Pelkey research group has made staurosporine analogs which the Mowery lab tests for biology activity. Recently, one compound was found to be highly potent against cancer cells and induce death by binding tubulin. Tubulin is a eukaryotic protein that is necessary for cell division. Because bacteria have a homologous protein, Fts‐Z, we wanted to determine if compounds acted as antibiotics. In addition, the Pelkey group has synthesized a suite of new compounds that are isomeric to our previously most potent ones. We are testing these compounds for anti‐cancer activity to determine what structural parameters are necessary to induce cell death.
Cardiac and pulmonary expression of renin, prorenin, mast cells and macrophages in a rat model of fat embolism syndrome
Authors: Siddiqui Gulnaz , Hamidpour Soheila , Mateescu Valerica , Monaghan Nichols Paula , Wacker Michael , Poisner Alan , Salzman Gary , Molteni Agostino 
Published: May 2022

Fat embolism induced in rats by intravenous injection of triolein(T) causes pulmonary inflammation, fibrosis, and vasculitis after 48 hours ort 10 weeks. Administration of Aliskiren, Captopril and Losartan drugs, which interfere with the renin angiotensin aldosterone system, ameliorates the pulmonary damage. Macrophages and mast cell number decreased with drugs administration. Hearts do not exhibit inflammation or vasculitis although significant emboli are detected at 48 hours. Pulmonary expression of renin, prorenin(R/P) positive cells are also increased after T injection. This study investigates whether the presence of R/P cells correlates with macrophages and mast cell invasion in the hearts and lungs.Methodology24 Sprague Dawley rats were divided into four groups and treated with 0.2 ml of T or Saline. Lungs and hearts from 3 animals from each group that were sacrificed 48 hours or 10 weeks, fixed in formalin and stained with Hematoxylin‐Eosin, Trichrome or immunostained with antibodies to CD117, CD68 to identify mast cells and macrophages. Sections of the heart and the lung were evaluated at 400X magnification. Cells were counted, histopathology examined and statistical significance evaluated using GraphPad software.ResultsWhile the lungs showed the previously reported, histopathological damage caused by the inflammation, vasculitis, fibrosis and cell necrosis, the hearts did not show such damage, thus confirming previous observations.Contrary to the lungs where the number of CD117, CD68 and R/P positive cells was significantly increased at both interval times, no difference in CD117, CD68, R/P positive cell numbers were observed in the heart. In the lungs, two distinct types of macrophages were identified, one large and the second one of normal size. Such histopathological changes were not observed in the hearts. Hearts exhibited distinct locations of CD117 and CD68 positive cells, with multiple cells located primarily near the myocardium and few in the adventitia of the coronary arteries, in contrast to lungs where the cells were mostly located around the arteries.ConclusionThe study confirms the previously reported histopathological difference of the T induced damage in the lungs compared to that of the hearts in this model of fat embolization. This finding highlights the variation in cellular response of diverse organs to fat embolism. This difference is not only related to the number of the inflammatory cells but also to their location in different organs as evidenced by the difference in the distribution and location of R/P cells in hearts and lungs. Future studies will investigate the underlying mechanisms that lead to pulmonary susceptibility while preserving cardiac integrity in response to a FE induced inflammatory response in order to better design a therapeutic intervention for the fat embolism syndrome.
Kisspeptin Reduces Airway Hyperreactivity and Remodeling in Asthmatic Ovariectomized Mice
Authors: Borkar Niyati A. , Ambhore Nilesh S. , Balraj Premanand , Sathish Venkatachalem 
Published: May 2022

RationaleEpidemiological data show changes in asthma occurrence with age and sex. After puberty, increased severity in women shows sex‐skewed occurrence of asthma in females vs. males. This implies the importance of female sex‐steroids, particularly estrogen in asthma pathophysiology. Greater asthma in women may represent detrimental mechanisms upstream to or independent of estrogen. Moreover, data from CNS studies show kisspeptin (Kp) signaling is modulated by estrogen. Our recent in vitro studies show Kp via its receptor, KISS1R regulates airway smooth muscle (ASM) cell proliferation. However, the relevance of endogenous estrogen on Kp/KISS1R signaling and their effect on regulating airway hyperresponsiveness (AHR) and remodeling is not yet explored. Accordingly, in this present study, we utilized intact female vs. ovariectomized (OVX) mice to isolate estrogen influence from the Kp effect in regulating AHR and remodeling in a murine model of allergic asthma.MethodsWild Type C57BL/6J intact female and OVX mice were procured from Jackson Laboratory, USA, and challenged intranasally with a mixed‐allergen (MA) for 28 days. On alternate days, animals from the treatment group received intranasal Kp‐10 (1.2mg/kg), vehicle group received PBS alone. On day 29, mice were anesthetized and subjected to SCIREQ flexiVent to measure lung mechanics like airway resistance (Rrs), elastance (Ers), compliance (Crs), tissue damping (G), and tissue‐elasticity (H). Following this, bronchoalveolar lavage (BAL) was performed for differential leukocyte count (DLC) and lung tissues were processed for histology using hematoxylin and eosin (H&E) and trichrome staining. Additionally, laser‐capture microdissection (LCM) assisted qRT‐PCR analysis in ASM cells was performed for genes relevant to airway remodeling.ResultsMA‐challenged intact female and OVX mice showed a significant increase in Rrs, Ers, G, H, and reduced Crs compared to PBS, more pronounced effects were observed in intact females. Kp‐10 treatment significantly reversed the MA‐induced changes with a decrease in Rrs, Ers, G, H, and increased Crs. Interestingly, in OVX mice we observed significant effects of Kp‐10 to improve the lung mechanics compared to intact females. Notably, Kp‐10 alone exposed group did not show any changes in lung mechanics compared to PBS. DLC in BAL showed Kp‐10 treatment significantly reduced MA‐induced inflammatory cell infiltration. Futhermore, histology studies showed Kp‐10 treatment significantly reduced MA‐induced smooth muscle mass and collagen deposition in airways.ConclusionOverall, this study shows the modulatory role of estrogen in regulating kisspeptin signaling, thereby AHR and remodeling. Thus, providing the relevance to higher asthma incidence and severity in women compared to men.
Utilization of zebrafish larvae to monitor gastric motility in diabetes mellitus: targeting GLP‐1 and GIP receptors
Authors: Hui Chung Man Jessica , Du Peng , Liu Yuen Hang Julia , Lu Zengbing , Cui Dexuan , Jiang Bin , Ngan Man Piu , Ng Shuk Han , Yang Lingqing , Khalid Aleena , Liu Luping , Rudd John A. 
Published: May 2022

BackgroundDiabetes mellitus (DM) is a prominent chronic disease associated with mortality and morbidity. The impact of DM is extensive, impacting with several major organs systems, including the gastrointestinal (GI) tract. For instance, the prevalence of DM in gastroparetic patients is approximately 30%. Glucagon‐like peptide‐1 (GLP‐1) and gastric inhibitory peptide (GIP) are hormones involved in glucose homeostasis but may also affect gastric motility. GLP‐1 and GIP receptors belong to class B G‐protein coupled receptors (GPCRs) and zebrafish GPCRs (zGPCRs) share structural similarities with the human GLP‐1 (hGLP‐1) and human glucagon receptors (hGCGR). Studies found that zebrafish GLP‐1 (zGLP‐1) receptors exhibit all the structural features of class B GPCRs and have ~50% homology with human GLP‐1 receptors. The aim of the studies is to establish experimental models of DM and investigate if GLP‐1 and GIP receptor agonists alter gastric function.MethodologyDiet‐induced DM zebrafish larvae models (from 5 days post fertilization (dpf) to 7 dpf) were established by (i) overfeeding, (ii) feeding with a high‐fat diet (egg yolk), (iii) exposure to high levels of glucose (30 mmol/L) or (iv) a knockdown of the pdx1 (insulin promoter factor 1) gene mutant. A body mass index (BMI) analyses and enzyme‐linked immunosorbent assays (ELISA) for insulin levels and glucose assay were used to grade DM. As obesity is associated with development of diabetes, adipose deposits in the abdominal area was also determined by an inverted microscope. Exendin‐4 and tirzepatide (100 µM – 1 nM) were administered via microgavage. Peristalsis was captured in anaesthetised animals using light microscopy and quantified in MATLAB using imaging velocimetry and pixel differences.ResultsExcept for the overfed and pdx1 mutated models, significant differences in BMI, insulin and glucose levels were observed relative to controls. The excess diet model showed high level of adipose deposits (2.4 ± 0.17 mm) and at 7 dpf an 11% increase in adipose area is seen but without DM properties (i.e. increase glucose levels and altered insulin levels). There were significant differences between DM models and control‐fed larvae in terms of mixing power, anterograde and retrograde peristalsis of several parameters including contractile intervals and velocity. Preliminary data indicated that larvae at7 dpf fed a standard diet, exendin‐4 (≥ 100 nM/larvae) and tirzepatide (≥100 µM/larvae) reduced motility in the anterior and mid‐intestine.ConclusionThree DM models and an obesity model using zebrafish larvae were successfully established. Advanced imaging and processing techniques revealed intricate subtypes of dysmotility in DM and obesity. Exendin‐4 and tirzepatide at high doses reduced motility in normal fish which may be consistent with their clinical side effect profile.
Role of the Phosphate Transport Facilitator XPR1 in Bone Homeostasis and Phosphate‐Dependent FGF23 Secretion
Authors: Cabuzu Daniela , Ramakrishnan Suresh , Bonny Olivier 
Published: May 2022

BackgroundEvidence point at Xenotropic and Polytropic retrovirus Receptor 1 (XPR1) as a protein involved in the cellular phosphate export pathway and phosphate homeostasis: systemic constitutive deletion of Xpr1 in mice is lethal and kidney‐specific deletion of Xpr1 induces hypophosphatemic rickets with hypercalciuria. XPR1 is expressed in the bone, but its function remains elusive. We hypothesized that XPR1 is crucial for bone homeostasis and that is involved in the sensing mechanism of phosphate in the bone.MethodsWe established an inducible whole body Xpr1 KO mouse model. The mice were placed in metabolic cages for urine and blood analysis, followed by femur uCT and histomorphometry. The Fgf23 mRNA and protein (c‐terminal and intact FGF23) levels were assessed from tibia and femur incubated ex vivo for 24h with increasing phosphate concentrations. Primary osteoblast cells were isolated from control and Xpr1 KO mouse calvaria.ResultsConditional total body Xpr1KO mice are constantly decreasing their body weight upon Xpr1 deletion, and develop profound hypophosphatemia, compared to their control littermates. Histomorphometry analysis and uCT on femurs of Xpr1 KO mice show high trabecular bone density, despite low bone formation rate and low number of osteoclasts. Increased intact FGF23 secretion by tibia and femur was observed in control mice in response to increased phosphate concentration in the media. However, the bone samples from Xpr1KO mice are resistant to phosphate induced FGF23 secretion. No changes were observed for the c‐terminal FGF23 in response to increased phosphate concentration, for both the control and Xpr1 KO mice.Osteoblasts were successfully prepared from control and Xpr1 KO mouse calvarie and Xpr1 expression was inactivated by tamoxifen treatment.ConclusionXPR1 is essential for phosphate homeostasis and FGF23 secretion upon phosphate exposure. Osteoblasts will now be used to further study phosphate dependent FGF23 secretion.