bluuebunny/crossref_metadata_2025_split huggingface dataset:
Aluminium Nanoparticles Released by Joint Implants ‐ Quartz Crystal Microbalance with Dissipation Analysis
Authors: Pêkala Jakub Radosław , Pêkala Przemysław Andrzej , Tomaszewska Iwona Maria , Santos-Martinez Maria Jose , Radomski Marek , Paziewski Mateusz Paweł , Pasieka Paweł Melchior , Tomaszewski Krzysztof Andrzej 
Published: April 2020

IntroductionThe rising popularity of joint prosthetics such as total knee arthroplasty, total disc replacement or total hip arthroplasty has woken serious concern of toxicity of the nanoparticles (NPs) released by the prostheses because of corrosion and wear. The NPs are known to influence blood components, but their impact on platelets has not been yet analyzed. In this study we aimed to assess the effect of Al2O3 (Al) NPs on thrombocytes in vitro with the use of novel quartz crystal microbalance with dissipation (QCM‐D) methodology.MethodsThe several NPs (Al2O3 5nm, Al2O3 10nm, Al2O3 20nm, Al2O3 30nm, Al2O3 50nm and Al2O3 80nm) were tested for their ability to induce platelet activation and aggregation with use of flow cytometry, light transmission aggregometry and QCM‐D. The results of the latter test were confirmed with optical microscopy and transmission electron microscopy.ResultsSignificant changes in dissipation (D) and frequency (F) were noted in platelet‐rich‐plasma incubated with all assessed NPs (concentration of 5, 2.5, 1, 0.5 μg/mL), in comparison to controls under flow. All tested NPs, except for the largest (80 nm) ones, induced a significant rise of both F and D, revealing thrombocyte aggregation even at the lowest tested concentration (0.5 μg/mL). Optical microscopy revealed platelet aggregation also for 80 nm NPs. In contrast, transmission electron microscopy of 80 nm NPs showed lack of platelet aggregation, however, the NPs caused formation of several platelets clumps similar to aggregates.ConclusionOur study provides evidence that Al NPs influence thrombocytes function in vitro. Moreover, different mechanism depending on the size of NPs has been noted. Smaller Al NPs induce platelet aggregation, whereas large particles penetrate the platelets, damaging them and releasing Ca2+ stores. It is not certain if the latter causes thrombosis in vivo. We believe that future in vivo studies might indicate safe aluminium level for patients with Al‐containing ceramic prostheses as well as establish which concentration would be optimal for revision surgery.
ONC201 and Its Potent Analogues Disrupt Mitochondrial Metabolic Function in Triple Negative Breast Cancer
Authors: Fennell Emily M.J. , Aponte-Collazo Lucas J. , Graves Paul R. , Herring Laura E. , Iwanowicz Ed J. , Holmuhamedov Ekhson , Graves Lee M. 
Published: April 2020

BackgroundONC201 is an imipridone compound in clinical trials for multiple cancer types, including triple negative breast cancer (TNBC). ONC201 is a promising anticancer therapy whose pharmacological target and function are not clearly defined. We have demonstrated that the target of ONC201 and its potent analogues (TR compounds) is the mitochondrial protease ClpP, consistent with previous reports of ONC201‐induced mitochondrial stress and depolarization in TNBC cells.Study ObjectiveThe objective of this study is to determine if ONC201 and TR compound treatment result in a loss of mitochondrial protein through activation of ClpP, leading to metabolic disruption in glutamine utilization and mitochondrial function.MethodsTo determine if ONC201 and TR compounds disrupt aerobic respiration, galactose was substituted for glucose in cell culture media. We used galactose‐containing cell culture media to shift cells from anaerobic to aerobic respiration, as galactose is utilized through aerobic respiration. The IC50 of ONC201 and TR compounds was measured with glucose‐ or galactose‐containing media by MTS. MitoPlate assays (Biolog) were performed to identify perturbations in the utilization of 30 different substrates in TNBC cells treated with ONC201 or TR compounds. Proteomic analysis of ONC201 or TR compound‐treated cells was conducted using LC‐MS.ResultsProteomic analysis revealed a large decline in mitochondrial peptides following ONC201 or TR compound treatment. We also demonstrated that substitution of glucose with galactose reduced the IC50 of ONC201 and TR compounds in TNBC cells. In addition, MitoPlate assays suggest a reduced utilization of TCA cycle substrates and L‐glutamine.ConclusionsAddition of galactose to cell culture media improved efficacy of ONC201 and TR compounds in TNBC cells. Sensitization and loss of mitochondrial peptides suggest that ONC201 and TR compounds cause loss of mitochondrial protein and reduction metabolic activity. Consistent with sensitization results, MitoPlate data demonstrates a loss of TCA cycle substrate and L‐glutamine utilization following ONC201 or TR compound treatment. Glutamine is known to facilitate both cell proliferation and energy production in cancer cells through protein biosynthesis and the TCA cycle. Proteomic analysis is being used to identify ClpP‐dependent protein loss. Uniformly 13C‐labeled substrates will be used to identify perturbations in energetic and biosynthetic pathways following ONC201 and TR compound treatment. Loss of mitochondrial metabolic activity and glutamine utilization may play a role in ONC201 and TR compound anticancer activity.Support or Funding InformationNIH Pharmacological Sciences T32 (GM007040), University Cancer Research Fund
Myogenic Activation and Endothelial Function in Cerebral Arteries with Metabolic Disease: Is Myogenic Tone Protective for the Endothelium?
Authors: Halvorson Brayden , Williamson Justin , McGuire John , Frisbee Jefferson 
Published: April 2020

While it has been well established that the development of metabolic disease, including hypertension, impaired glycemic control, etc. can be associated with increased myogenic activation of cerebral resistance arteries and arterioles, the impact of this shift in pressure‐induced responses on integrated vascular function remains elusive. Using male obese Zucker rats (OZR) at 17–18 weeks of age, we determined that changes to myogenic activation of ex vivo pressurized middle cerebral arteries (MCA) was best predicted by the severity of elevation in mean arterial pressure and allowed for stratification into three groups (mild, moderate, high degrees of elevation in the slope of myogenic activation vs. intravascular pressure).While dilator responses to endothelium‐dependent stimuli (e.g., acetylcholine) were attenuated in all MCA of OZR, the severity of the attenuation was correlated with the degree of increase in myogenic activation from normal for that vessel. Treatment of the vessels with the anti‐oxidant TEMPOL significantly improved vascular responses to acetylcholine in the mild and moderate myogenic activation groups of MCA from OZR, but had minimal impact on high myogenic response groups. In contrast, treatment of vessels with the mechanosensitive cation channel inhibitor gadolinium chloride to reduce myogenic activation in OZR MCA to levels comparable to that of control LZR had minimal impact on endothelial function in MCA from the mild and moderate groups, but significantly improved endothelium‐dependent responses in MCA from the high group. Combined treatment of OZR MCA with both gadolinium chloride and TEMPOL resulted in endothelium‐dependent responses being very comparable across groups.Assays for vascular nitric oxide and PGI2 bioavailability provided correlative evidence that endothelial function, while still impaired in OZR in general, may be better maintained in vessels from animals with a higher myogenic activation than would have otherwise been predicted.Calculations suggest that the increased myogenic activation in the “high” group may serve to reduce wall tension in response to the elevated arterial pressure and that this may contribute to a mechanism that partially protects endothelial function.Support or Funding InformationCIHR #389769; NSERC RGPIN‐2017‐04536 and RGPIN‐2018‐05450
Inhibition of stearoyl‐CoA desaturase suppresses growth of pancreatic tumors in vitro and in vivo
Authors: Skrypek Kaitlin , Balog Steven , Asahina Kinji 
Published: April 2020

Pancreatic ductal adenocarcinoma (PDAC) is a relatively rare cancer type, but is the fourth‐leading cause of cancer death in the US. Although chemotherapy and immunotherapy have been used for patients with PDAC, the overall five‐year survival rate is 8% and there is an urgent need for effective therapies. Stearoyl‐CoA desaturase (SCD) is an enzyme localized in the endoplasmic reticulum and generates monounsaturated fatty acid from saturated fatty acid by introducing a single double bond. In the present study, we examined the role of lipid metabolism regulated by SCD in PDAC growth and survival using Pdx1Cre; LSL‐KrasG12D mice and human PDAC cell lines. We isolated pancreatic tumors expressing epithelial cellular adhesion molecule by magnetic‐activated cell sorting from the Pdx1Cre; LSL‐KrasG12D mouse pancreas and formed tumor organoids in matrigel. We found that a specific SCD inhibitor (A939572) induces degeneration of the tumor organoids. Interestingly, addition of oleic acid (18:1), but not stearic acid (18:0), rescued the inhibitor‐induced degeneration of tumor organoids. Treatment with the SCD inhibitor increased mRNA expression of unfolded protein response (UPR) markers, such as Atf4, Atf6, Ddit3, spliced Xbp1, and Grp78 in organoids. The increased expression of these genes was reversed by addition of oleic acid, but not stearic acid. Similarly, the SCD inhibitor suppressed the proliferation of PANC‐1, a human PDAC cell line. The SCD inhibitor induced the expression of the UPR markers in PANC‐1 and their induction was suppressed by oleic acid, but not by stearic acid. After injection of the SCD inhibitor to Pdx1Cre; LSL‐KrasG12D mice bearing pancreatic tumors, we observed TUNEL+ cells in pancreatic tumors, but not in normal acinar cells. Our data suggest that the inhibition of SCD causes UPR and cell death in pancreatic tumors.Support or Funding InformationPilot project funding from NIH/NIAAA grant P50 AA011999, USC Dean’s pilot project program
(Pro)renin Receptor Antagonism Attenuates High Fat Diet Induced Non‐alcoholic Fatty Liver Disease
Authors: Gayban Ariana Julia B , Worker Caleb J , Anakatumpunya Thananun , Earley Yumei Feng 
Published: April 2020

Non‐alcoholic fatty liver disease (NAFLD) represents a diverse array of liver damage linked to obesity, and metabolic syndrome. The mechanisms and the treatment for NAFLD remains lacking; however, recent evidence suggests a critical importance of the (pro)renin receptor (PRR) and the renin‐angiotensin system (RAS) in liver lipid metabolism. Our laboratory recently developed a novel PRR antagonistic peptide PRO20 that blocks the fibrotic signaling of the PRR and the activation of the RAS. We hypothesize that PRR antagonism reverses NAFLD development by preventing the activation of liver RAS and fibrotic signaling. To test this hypothesis, wild‐type male C57Bl/6J mice (n=9–10/group) were fed with either HFD (60% calories from fat) or normal fat chow (NFD, 10% calories from fat) for 6 weeks. Two weeks following diet modification, mice were implanted with a subcutaneous osmotic pump containing either PRO20 or scramble peptide (700 μg/kg/d, 4 weeks). At the end of the 6‐week protocol, liver tissues were harvested and processed for Oil Red O (ORO) and Masson’s trichrome staining for assessment of lipid and collagen accumulation respectively. In scramble peptide treated groups, we found that 6 weeks of HFD induced a significant elevation on liver ORO staining (15.90 ± 1.49 %;) compared with the liver from mice fed with NFD (3.60 ± 1.61 %, p < 0.0001). More importantly, PRO20 (9.91 ± 1.46 %; p = 0.001) significantly reduced the ORO staining compared with scramble peptide in mice treated with HFD. Portal vein collagen deposition was significantly lower in mice treated with PRO20 (1.93 ± 0.60%) compared to the control peptide (4.05 ± 0.60%, p < 0.0211) following 6 weeks of HFD. Mechanistically, we found that PRO20 (1.99 ± 0.62) normalized the elevation of liver mRNA level (fold change) of peroxisome proliferator‐activated receptor gamma (PPARγ) induced by HFD (HFD Scramble peptide: 2.61 ± 0.47 vs. NFD Scramble peptide: 1.13 ± 0.47, p = 0.0037), a key transcription factor regulating lipogenic genes in the liver. In addition, PRO20 prevented the activation of key liver RAS components induced by HFD including the angiotensinogen (1.00 ± 0.62 vs. 6.153 ± 0.62, p < 0.0001), angiotensin converting enzyme (1.03 ± 0.63 vs. 2.91 ± 0.63, p = 0.0344), and angiotensin II type 1a receptor (0.35 ± 0.46 vs. 2.20 ± 0.46, p = 0.0091 value). In summary, our data showed that subcutaneous infusion of PRO20 attenuated the development of HFD‐induced NAFLD and portal fibrosis by regulating liver PPARγ and preventing liver local RAS activation. We conclude that PRR antagonism maybe a new therapeutic target for the treatment of NALFD.Support or Funding InformationNIH/NHLBI (R01HL122770), American Heart Association (17IRG33370128), NIH/NIGMS (1P20GM130459‐5451)
Dual Oxidase 2 as a Mediator of Podocyte Injury in the Diabetic Environment
Authors: Syed Maaz M. , Abraham Sachin , Ford Bridget Marie 
Published: April 2020

Glomerular injury is a prominent pathological feature of diabetic nephropathy (DN). In glomerular epithelial cells, or podocytes, hyperglycemia alters slit diaphragm proteins and causes foot process effacement, apoptosis and cell detachment. Oxidative stress has emerged as an important pathogenic mechanism in the development of glomerular injury in DN. However, the mechanisms by which these factors exert their action remain poorly understood.We provide evidence that the NADPH oxidase of the Nox family, Dual oxidase 2 (Duox2), is present in cultured glomerular cells, including podocytes. Exposure of cultured podocytes to high concentrations of glucose (HG) elicited a rapid upregulation of Duox2 protein expression. Inhibition of Duox2 with specific siRNA prevented the HG‐induced increase in intracellular reactive oxygen species (ROS) generation and hydrogen peroxide (H2O2) production in cultured podocytes.In additional experiments, we established a functional link between Duox2‐derived ROS generation and podocyte injury in response to HG. Impairment of Duox2 function nearly abolished HG‐mediated DNA fragmentation, apoptosis and decrease in/reorganization of slit diaphragm protein expression in podocytes, indicating that Duox2 is required for the deleterious effects of glucose in podocytes.Our study demonstrates, for the first time, that Duox2 is responsible for increased ROS generation and subsequent alteration of podocyte function in response to HG. Our work serves as proof of concept to demonstrate the utility of targeting Duox2 as a future therapeutic intervention to reduce diabetes‐mediated glomerular lesions.Support or Funding InformationThis project was funded by the University of the Incarnate Word, Office of Research and Graduate Studies and the following grants: NRSA 5T32HL007446‐32
Epidural Stimulation Targeting Lower Urinary Tract Function in Spinally Intact and Transected Urethane‐Anesthetized Rats
Authors: Hubscher Charles , Hoey Robert , Medina-Aguinaga Daniel , Khalifa Fahmi , Zdunowski Sharon , El-Baz Ayman , Herrity April , Harkema Susan 
Published: April 2020

Bladder management for conditions such as spinal cord injury (SCI) includes a combination of catheterization (either self‐intermittent or suprapubic) and pharmacological approaches, which targets maintenance but does not promote recovery of function. We have exciting data from multiple individuals receiving spinal cord epidural stimulation (scES) that is optimized for stepping and standing, in combination with task‐specific training, that shows improvements in lower urinary tract function. The objective of our current functional mapping pre‐clinical animal studies is to identify scES configurations (electrode location, amplitude and frequency) that can promote optimal neural control of urine storage (adequate bladder capacity at safe pressures without incontinence) and sufficient controlled emptying (high voiding efficiency at safe leak point pressures). Initial mapping was done in acute anesthetized terminal preparations during cystometry (bladder filling) using a modified Medtronic Specify 5‐6‐5 epidural array that is being used by our group in parallel human scES studies. The current data compares the response to scES in spinally intact and transected male and female rats 6 weeks post‐injury at T13‐L1 (level of sympathetic supply), L3‐4 (region with circuits related to external urethral sphincter control) and L6‐S1 (level of parasympathetic supply) spinal segments. Results indicate that scES storage effects and voiding efficiency were dependent upon presence/absence of spinal transection, frequency and intensity stimulation patterns, electrode location, and sex of the animals. Taken together these results suggest that the circuitry is dissociable and amenable to stimulation that seeks to promote either storage or voiding. Furthermore, our innovative approach and novel application of this Medtronic Specify 5‐6‐5 epidural device will generate functional maps that will lay the groundwork for expedient translation of this promising technology to individuals with SCI as well as provide a powerful tool for elucidating underlying circuits present in the lumbosacral cord that are involved in urogenital function.Support or Funding InformationNIH SPARC OT2OD024898
Lactate stimulates central respiratory motor output in bullfrogs, Lithobates catesbeianus
Authors: Burton Michael T. , Santin Joseph M. 
Published: April 2020

Ventilation must constantly change to meet varying metabolic and acid‐base regulation needs of the organism. Although O2 and CO2/pH sensors have received much attention for the chemical control of breathing, metabolites such as lactate and ATP have recently been shown to play important roles in both the hypoxic and hypercapnic ventilatory responses of vertebrates. In mammals and fish, lactate anions increase ventilation through peripheral mechanisms, but the actions of lactate in the central respiratory network of any vertebrate species remain unclear. Anuran amphibians (frogs and toads) accumulate large amounts of lactate in the brain during periods of high respiratory drive, suggesting that lactate may act at central sites to stimulate breathing. For example, hypoxia increases brain lactate which may contribute to elevated ventilation following physiological hypoxia caused by breath‐holding. Furthermore, anurans perform mainly anaerobic exercise, leading to large lactate loads in the blood that may get delivered to the brain through transporters present in the blood‐brain barrier. Thus, we tested the hypothesis that lactate stimulates output from the central respiratory network in amphibians. To test this hypothesis, we measured respiratory‐related cranial nerve X (CNX) and hypoglossal nerve (SNII) activity in isolated brainstem‐spinal cord preparations from the American bullfrog, Lithobates catesbeianus, in response to sodium lactate (lac−; n=8). The brainstem‐spinal cord preparation is advantageous because we can assess the actions of lac− on rhythm generating and motor functions of the respiratory network independent of peripheral feedback. Lac− failed to increase frequency of the respiratory rhythm and amplitude of CNX output. However, we identified a striking dose‐dependent increase in amplitude of respiratory‐related SNII output in each preparation, indicating enhanced motor neuron firing and/or recruitment by lac− (P=0.008; Friedman test; 0.5 mM= 33±11, 2 mM= 56±19, 4 mM= 89±29 % increase above baseline). To control for slight increases in [Na+], osmolality, extracellular pH, and time during exposure to sodium lactate, we superfused a separate group of preparations with 0.5, 2, and 4 mM sodium bicarbonate (HCO3−; n=4). HCO3− did not increase the motor amplitude of either SNII or CNX (P>0.9; Friedman test). Thus, lactate anions lead to increased respiratory motor output of SNII, which may enhance activation of buccal floor musculature during periods of high respiratory demand such as hypoxia and exercise. Overall, this work directly implicates lactate anions in the control of central motor networks that regulate breathing in vertebrates.Support or Funding InformationThis work was funded by start‐up funds provided by UNC‐Greensboro to JS.
The Size and Shape of the Alveolar Process: A Morphometric Analysis of the Dental Arch During Fetal and Infantile Development
Authors: Cusick Abbey Marie , Zdilla Matthew J. 
Published: April 2020

The development of the alveolar process is closely tied to numerous oral pathologies, including cleft lip and cleft palate. Despite the importance of the alveolar process, little gross anatomical study has been performed with regard to its development. Therefore, this study analyzed 187 dry maxillae from 109 individuals aged from five‐months intrauterine to five‐months post‐natal. Distances between the centers of the five alveoli were measured via photogrammetry. Interalveolar distances and age (months development) were utilized to develop best‐fit regression equations. Paired‐samples t‐tests were performed between left‐ and right‐sided interalveolar distances. Also, geometric morphometric analysis was performed and included canonical variate analysis to identify shape change among different age groups and between‐block partial least squares analysis to assess covariation in the premaxillary alveolar process and alveolar process of the maxilla proper. The interalveolar parameter most closely related to age was that of the intermolar distance (Distance = [−0.02962(age2)] + [0.8854 (age)] + 0.7475; r2=0.5983). Additionally, three out of four inter‐alveolar distances in addition to the total length of the dental arch significantly differed between the left and right sides (p=0.0003, p=0.0027, p <0.0001, p=0.0078, respectively). Alveolar arch shape was significantly different among most age groups; this was especially the case when there was a greater difference in age (i.e., early intrauterine vs late post‐natal). Furthermore, PLS analysis demonstrated a strong relationship between the shapes of the premaxilla and maxilla proper (Correlation coefficients of PLS1 and PLS2 were 0.73 and 0.70, respectively). The results of this study improve the understanding of alveolar process growth― age is best estimated by intermolar distance (and vice‐versa), there is asymmetry between left‐ and right‐sided maxilla growth, dental arch shape changes with age, and the shape of the premaxilla is closely related to the shape of the maxilla proper.Support or Funding InformationFunding: WV Research Challenge Fund [HEPC.dsr.17.06]