bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inhibition of CYP3A7 by Ritonavir and Lopinavir Leads to Adrenal Insufficiency in the Developing Infant by Blocking DHEA‐S Oxidation
Authors: Kandel Sylvie E. , Han Lyrialle W. , Mao Quingcheng , Lampe Jed N. 
Published: June 2021

CYP3A7 is the predominant CYP3A isoform in the neonate and developing infant. Its primary function is the 16α‐hydroxylation of the endogenous hormone DHEA‐S, which is important for downstream maintenance of hormone homeostasis in the adrenal gland. Newborns infected with HIV are typically treated with a combination therapy of Lopinavir and the pharmacokinetic enhancer Ritonavir. However, adrenal insufficiency due to increased DHEA‐S concentrations, and premature birth, have been reported in this treatment population, leading to adverse outcomes in this fragile patient group. Given that Ritonavir is a known potent inhibitor of CYP3A4, we hypothesized that it might also be an inhibitor of CYP3A7‐mediated DHEA‐S oxidation and that this inhibition might be responsible for the adrenal insufficiency and other side effects associated with Lopinavir‐Ritonavir treatment. Indeed, we observed significant inhibition of CYP3A7 DHEA‐S hydroxylation activity in the presence of Ritonavir with an IC50 of 0.05 μM. Furthermore, Ritonavir displayed time‐dependent inhibition of DHEA‐S oxidation, with a Ki of 0.336 μM and a Kinact of 0.1077 min−1, suggesting that it may be a mechanism based inactivator of CYP3A7. Lopinavir was also capable of inhibiting CYP3A7, albeit to a much lesser extent than Ritonavir with an IC50 of 5.88 μM for DHEA‐S 16α‐hydroxylation, and without the associated time‐dependency. Interestingly, Lopinavir alone has a much higher intrinsic clearance rate in fetal liver microsomes compared to adult liver microsomes, indicating the need for a pharmacokinetic enhancer adjuvant in order to slow clearance and maintain efficacy. However, our results suggest that closer monitoring of the effective dose of the pharmacokinetic enhancer may be required in order to prevent significant inhibition of CYP3A7 DHEA‐S oxidation and the associated adverse effects.Support or Funding InformationThis work was supported by the National Institutes of Health, Institute of General Medical Sciences [Grant P20‐GM103549‐07]/ National Center for Research Resources [Grant P20‐RR021940] and Kansas IDeA Network of Biomedical Research Excellence [Grant QH846868‐KINBRE] to JNL.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Human a1A‐adrenergic receptor phosphorylation, internalization and desensitization.
Authors: Rocio Alcantara Hernandez 
Published: June 2021

The a1A‐adrenergic receptor (a1A‐AR) is a G protein coupled‐receptor (GPCR) that signals through the Gq/ phospholipase C/ calcium release pathway. This adrenergic receptor subtype modulates important cellular responses and it is also involved in the pathogenesis of diseases. Phosphorylation of intracellular loops and the carboxyl terminal tail of a1A‐AR is part of their fine regulation, generally associated with desensitization/internalization processes, in which different protein kinases participate, Including second messenger‐activated protein kinases, such as protein kinase C isoforms (PKCs) and G protein‐coupled receptor kinases (GRKs).In silico analysis of the human a1A‐AR amino acid sequenced, suggested a series of possible phosphorylation sites targeted by PKCs, GRKs and also for the glycogen synthase protein kinase‐3 (GSK3). GSK3 is an important element into signal transduction of diverse receptor systems, and the phosphorylation on specific substrates can modulates enzyme activity, subcellular localization, stability of the target protein and protein‐protein interactions. We observed using a1A‐AR immunopurification and mass spectrometry analysis that in cells treated with noradrenaline, oxymetazoline or phorbol esters four serines that are target of GSK3: S229, S258, S352 and S381, are phosphorylated. However, the specific GSK3 inhibitor, SB216763, did not block the a1A‐AR desensitization induced by noradrenaline or oxymetazoline. This suggested that other protein kinases play major roles in such agonist‐induced desensitization. Interestingly, phorbol ester‐induced a1A‐AR desensitization was increased by the GSK3 inhibitor. In cellulo colocalization assays of a1A‐AR‐GSK3, showed increased interaction of these proteins in the presence of agonists and phorbol esters. Interestingly, expression of a GSK3 dominant‐negative mutant interferes with a1A‐AR internalization in response to NA and OXY, but this effect does not occur when cells are pretreated with PMA. All these data suggest the possibility that GSK3 might play a role in the regulation of a1A‐AR function and localization.Partially supported by Grants from Dirección General de Asuntos del Personal Académico (IN200718) and Consejo Nacional de Ciencia y Tecnología (Fronteras 882 and 253156).This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Constitutive Activation of Stat Signaling in Fibroblast‐like Synoviocytes Derived from Patients with Juvenile Idiopathic Arthritis Is Inhibited by Methotrexate
Authors: Singh Rakesh , van Haandel Leon , Leeder J. Steven , Becker Mara , Funk Ryan 
Published: June 2021

BACKGROUNDMethotrexate (MTX) is the cornerstone of treatment in the management of autoimmune arthritis, including juvenile idiopathic arthritis (JIA). Despite being in use for over 35 years the mechanism through which MTX inhibits inflammation remains unclear. In this study we investigate activation of JAK/STAT signaling in fibroblast‐like synoviocytes from patients with JIA and the effect of MTX.METHODSSynoviocytes were isolated from the synovial fluid of juvenile idiopathic arthritis patients following routine arthrocentesis and maintained in culture. Synoviocytes were treated with MTX and assessed for cellular levels of MTX and its polyglutamated metabolites, as well as intermediates of nucleotide biosynthesis, including dUMP and ZMP. Analytes were detected by UPLC‐MS/MS. JAK/STAT signaling was assessed in synoviocytes and A549 human lung carcinoma cells by Western blotting and immunofluorescence. Experiments were performed in triplicate and statistical testing was done by unpaired t test analysis.RESULTSMTX was actively taken up and metabolized in synoviocytes to form polyglutamated metabolites of MTX, however, MTX failed to cause measurable inhibition of de novo nucleotide synthesis by dUMP and ZMP analysis. Synoviocytes displayed a high level of STAT phosphorylation with 58.8±4.8% of total measureable STAT3 signal and 69.9±7.3% of total measureable STAT5 signal. In contrast, phosphorylation of STAT3 and STAT5 was undetectable in A549 cells and treatment with 100 ng/mL of recombinant IL‐6 resulted in a marked increase in STAT phosphorylation with 64.4±6.0% of measureable STAT3 signal and 76.6±8.5% of measureable STAT5 signal. Treatment with MTX resulted in inhibition of STAT3 and STAT5 phosphorylation by 38.1±3.4% (p<0.05) and 61.2±7.8% (p<0.05) in primary synoviocytes and 65.3±2.8 (p<0.05) and 92.8±8.1% (p<0.01) in IL‐6 stimulated A549 cells, respectively. In comparison, phosphorylation of STAT3 and STAT5 in response to IL‐6 stimulation in A549 cells was decreased by 91.6±11.3% (p<0.001) and 94.5±12.3% (p<0.001) by 50 μM of JAK Inhibitor I (CAS 457081‐03‐7). In A549 cells inhibition of STAT phosphorylation by MTX was completely reversed by co‐treatment with 100 μM folinic acid.CONCLUSIONThese findings support constitutive activation of JAK/STAT signaling in fibroblast‐like synoviocytes isolated from patients with JIA that is inhibited by treatment with MTX. Although the underlying biochemical mechanism through which MTX inhibits JAK/STAT signaling is not known, it appears to be dependent on the anti‐folate activity of MTX. Together, this data supports inhibition of JAK/STAT signaling as a possible mechanism of anti‐inflammatory activity of MTX.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Enhancing pre‐clinical in vitro cardiotoxicity assays with bioengineering strategies in a high‐throughput manner
Authors: Fisher Elliot , Ghazizadeh Hamed , Gray Kevin M , Geisse Nicholas A 
Published: June 2021

Stem‐cell based in vitro cardiotoxicity assays hold great promise for mitigating the cost of drug development. These assays have the potential to be more predictive of drug arrhythmogenicity than contemporary screening methods which rely on singe ion channel recordings. However, stem cell assays have several important shortcomings when detecting and classifying the risk profile of several known compounds. One likely source of this error is the maturity of the cells; most phenotypes are indicative of a fetal developmental stage. To enhance the predictive power of stem‐cell based assays, we have implemented bioengineering techniques to control the cell's culture surface. We utilized standard photolithography techniques to create nanoscale biomimetic grooves that mimic the shape and structure of collagen on a polymer‐coated glass layer. The fabrication technique allows for generation of this pattern on standard formats and permits use of high‐NA fluorescence microscopy. Using this approach we demonstrate that biomimetic engineering enhances several structural and biochemical phenotypes including sarcomere spacing, myofibril alignment, and sarcomere width. We extended this technique to pattern the surface of micro‐electrode arrays, and demonstrate that these ECM‐based cues enhance the electrophysiological response of cardiomyocytes to various drugs of known action that fail to elicit in vivo responses to drugs in vitro and recapitulated physiological IC50s when compared to traditional assays.Support or Funding InformationNIH SBIRThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Vitamin A content of beef and chicken liver revisited: variability and its implications for complementary feeding programs for infants.
Authors: Mazariegos Manolo , Romero‐Abal Maria Eugenia , Solomons Noel W. , Craft Neal E. 
Published: June 2021

Background:Because beef (BL) and chicken liver (CL) are rich sources of Vitamin A (VA) and of key minerals, their consumption has been proposed in food‐based complementary feeding programs. Literature values for VA content and its variability in liver are inconsistent.Objectives:To determine the VA content and its variability in BL and CL.Methods:13 samples each of BL and CL were purchased in Guatemalan markets. Each sample was split and analyzed by HPLC (Craft Technologies), both as raw (R) and steamed (S).Results:Mean±SD of BL content of VA (ug/100g) at 21776±9433 (CI, 95%, 17882 – 25670; SE, 1887) tended to be greater than CL at 17734±6232 (CI, 95%, 15102 – 20366; SE, 1272) (p>0.05). The respective CVs for BL and CL were 43.3%, and 35.1%. R and S contents were comparable in both BL and CL. VA content in BL and CL was much higher than comparative USDA values (2005).Conclusions:To meet 500 ug RDAs for VA in infants, it would require 2.3 – 3.3 g/d or 16 – 23 g/wk of BL. DRIs for Fe and Zn would be unattainable from liver without surpassing the 600 ug ULs for retinol. The high content of VA in liver and the variability attests its potential, but raises a note of caution for its use in programs combating infant micronutrient malnutrition.Sponsored by the Sight and Life
Initial synthesis and characterization of an alpha7 nicotinic receptor cellular membrane affinity chromatography column: Effect of receptor subtype and cell type
Authors: Moaddel Ruin , Oliveira Regina , Kimura Tomoko , Hyppolite Patrick , Juhaszova Magdalena , Bernier Michel , Wainer Irving 
Published: June 2021

Objective:In this study, cellular membrane fragments from SH‐EP1‐pCEP4‐hα7 and α7 HEK‐293 cell lines were used to synthesize cellular membrane affinity chromatography (CMAC) columns containing functional α7 nicotinic acetylcholine receptors, CMAC(α7 nAChR) columns.Methods:The synthesis of stable columns required the addition of cholesterol to the 2% cholate solubilization/immobilization (s/i) buffer and to the mobile phase. In addition, when membranes from the SH‐EP1 cell line were used L‐α‐phosphatidyl serine and L‐α‐phosphatidyl ethanolamine also had to be added to the s/i buffer.Results:A CMAC(α4β2 nAChR) column was prepared using membrane fragments from a SH‐EP1‐pCEP4‐hα4β2 cell line and this process required the addition of L‐α‐phosphatidyl serine and L‐α‐phosphatidyl ethanolamine to the s/i buffer, but not cholesterol. The s/i buffers from the 3 columns were compared with the s/i buffer utilized in the preparation of a CMAC (α4β2 nAChR) column prepared using an α4β2 HEK‐293 cell line, which required no additions to the 2% cholate s/i buffer.Conclusion:The data demonstrates that both cell type and receptor type affect the protocol required to produce a stable CMAC column and that, at the current time, the development of an optimum immobilization protocol is an empirical process.
Roles of nitric oxide and K+ channels in the vasodilatory action of nicotine in the rat renal vasculature
Authors: El‐Mas Mahmoud M , El‐gowilly Sahar M , Goher Eman Y , Ghazal Abdel‐Rheem M 
Published: June 2021

We investigated the mechanism(s) of the renal vasodilatory action of nicotine in rats. Nicotine vasodilation in phenylephrine‐preconstricted perfused kidneys was evaluated in the absence and presence of inhibitors of nitric oxide synthase (NOS), K+ channels, cholinergic or adrenergic activity. Nicotine infusion (5×10−5, 1×10−4−5×10−4 M) produced concentration‐dependent decreases in the renal perfusion pressure. Endothelium denudation with 3‐[(3‐cholamidopropyl)‐dimethyl‐ammonio]‐1‐propane‐sulfonate (CHAPS, detergent), or inhibition of NOS (NG‐nitro‐L‐arginine), guanylate cyclase (methylene blue) or muscarinic receptors (atropine) almost abolished nicotine vasodilation. The latter was also attenuated after blockade of ATP‐sensitive (KATP, glibenclamide) or inward rectifier (Kir, BaCl2) K+ channels but remained unaltered after blockade of calcium (tetraethylammonium) or voltage (4‐aminopyridine) dependent K+ channels. Hexamethonium, propranolol, guanethidine, or the use of KCl‐preconstricted kidneys reduced nicotine vasodilation in contrast to no effect for diclophenac or neostigmine. These findings implicate cholinergically (muscarinic)‐mediated activation of endothelial NOS and KATP and Kir channels in the renal vasodepressor effect of nicotine. Neurogenic NO also contributes to nicotine vasodilation.Supported by Faculty of Pharmacy, Univ. of Alexandria, Egypt.
Effects of prenatal stress on cardiovascular regulation in offspring
Authors: Hines Tina 
Published: June 2021

Certain prenatal disorders increase risk for cardiovascular disease in adult offspring. We tested the effect of reduced uterine perfusion (RUP) during pregnancy on arterial pressure (AP), baroreflex and stress regulation in adult rat offspring.Uterine vessels were clipped (RUP) on gestational day 14. Resting AP, baroreflex control of heart rate (HR), and AP, HR and glucose and corticosterone (cort) responses to 60‐min. restraint stress were measured in conscious chronically instrumented offspring. Baroreflex control of renal sympathetic nerve activity (RSNA) was assessed in anesthetized offspring.Resting AP was ~10mmHg higher in RUP offspring from 8–12wks in males and 8–20 wks in females. Baroreflex control of HR and RSNA was similar in all groups of 8wk offspring. AP and HR at 10 and 60 min. of restraint were also similar among offspring groups. Glucose levels after 10 min. of restraint were lower in RUP male offspring, and plasma cort was lower after 60 min in this group compared with control male offspring. The cort response to stress peaked at a higher level in RUP female offspring at 10 min. and remained higher than control at 60 min (~140ug/dl).Resting AP is modestly increased in adult male and female RUP offspring. Baroreflex regulation of HR and RSNA does not appear to be adversely affected in these rats. Results suggest sex differences in metabolic and hormonal responses to stress in RUP offspring. NIH NR04184.
Changes in gain of baroreflex control of heart rate during delivery and the early post partum period of the rat
Authors: Goldman Robert K , Azar Afaf S , Mulaney Julia M , Brooks Virginia L 
Published: June 2021

Pregnancy decreases baroreflex sensitivity (BRS) at end gestation (EG) in several species. However, the effects of labor and delivery on BRS, and the time at which BRS normalizes during the postpartum (PP) period, are unknown. Because oxytocin, which influences BRS, is released during labor and delivery, we hypothesized that this release may alter BRS. In addition, the maternal plasma levels of placental hormones rapidly normalize PP, suggesting that BRS will improve quickly after delivery. To test these hypotheses, blood pressure (BP) was measured continuously by telemetry (1000 Hz) in female rats (n=5) during the non‐pregnant state (NP), EG, delivery and days 2–10 PP. Pups were removed soon after delivery. Cardiovagal BRS was estimated using the sequence method, which selects spontaneous relationships between ramps in systolic BP and associated changes in pulse interval. Compared to NP, BP and BRS were decreased, and HR was increased, at EG (all P<0.05; Table:*). However, during delivery BRS increased from 1.23±0.09 to 1.65±0.08 msec/mmHg (first 2 hr; P<0.01), but rapidly decreased again (to 1.26±0.7 msec/mmHg) within 2 hr after delivery. By PP3, MAP and HR were recovered (P<0.05 compared to EG; Table,†); however, BRS did not increase significantly until PP6 (P<0.05; Table, †).In conclusion, cardiovagal BRS increases during delivery, and the mechanism may involve increased oxytocin. In addition, the prolonged time for BRS to recover during PP, in contrast to BP and HR, suggests that different mechanisms are responsible. Supported by HL70962, AHA and Collins Fdn.
Glycemic Index Reduction by a Viscous Polysaccharide Blend Independent of Food Form: Determination of the Glycemic Reduction Index Potential (GRIP)
Authors: Jenkins Alexandra , Vuksan Vladimir , Kacinik Veronica , Lyon Michael 
Published: June 2021

Objectives: To determine the extent to which a novel viscous polysaccharide blend (VPB), reduces post prandial glycemia and the glycemic index (GI) when added to either a liquid or a solid meal. VPB is commercially known as PGXTM.Methods: Two groups of 10 healthy subjects (5M, 5F; age, 35.6 ± 13.2 y; BMI 24.6 ± 2.1 kg/m2; and 3M, 7F; age, 33.5 ± 11.1y; BMI 26.3 ± 5.2 kg/m2), participated in an acute randomized controlled study. Zero, 2.5, 5 and 7.5 g of VPB was added to either a glucose drink or white bread (WB) and margarine (Marg). All meals contained 50g of available carbohydrate. Capillary blood samples were taken fasting and at 15, 30, 45, 60, 90 and 120 min after the start of the meal. Control meals (glucose or WB) were repeated 3 times.Results: Addition of VPB to glucose and white bread significantly reduced blood glucose iAUC irrespective of dose (p<0.01). The GI of glucose alone, and glucose and 2.5g, 5g or 7.5g were 100, 84, 78 and 73 respectively, the GI of the white bread, WB+Marg, WB and 2.5, 5g or 7.5g of VPB were 71, 67, 48, 37, and 34 respectively. The Glycemic Reduction Index Potential (GRIP) per g of VPB was 4.9±0.9 with glucose and 7.0±1.3 GI units with WB.Conclusion: The novel viscous fiber blend, is highly effective in lowering the glycemic index of a food irrespective of food form. Estimated GRIP for the VPB was 5 units when added to liquid and 7 units when added to a solid food.Sponsor: InovoBiologic, Inc, Calgary
Food Choices of Food Stamp Participants: Opportunities for Policy and Educational Interventions
Authors: Fox Mary Kay , Cole Nancy 
Published: June 2021

The overarching aim of the Food Stamp Program (FSP) is to ensure that low‐income households have enough food to eat. Over time, as evidence has accumulated about the role diet plays in the development of chronic disease, the program's goals have shifted to include an interest in the quality of foods eaten by FSP participants. Interest in diet quality has also been fueled by the ongoing obesity epidemic in the U.S., the high prevalence of obesity among some segments of the FSP population, and speculation that participation in the FSP and other Federal food assistance programs may be contributing to this problem Recently, some health advocates have recommended that the FSP implement more specific strategies to promote healthful food choices among FSP participants.This study analyzed data from the National Health and Nutrition Examination Study (NHANES 1999–2006) to examine dietary patterns and food choices of FSP participants. Analyses revealed that the subgroup of FSP participants with the most problematic dietary patterns is adult females. Additional analyses compared dietary patterns of overweight and obese females to identify specific food choices that might be targeted in educational or policy interventions to improve overall diet quality of this high‐risk subgroup of FSP participants.
Almonds and Biomarkers of Lipid Peroxidation: A Randomized Controlled Cross‐over Trial
Authors: Josse Andrea R. , Kendall Cyril W. C. , Marchie Augustine , Nguyen Tri H. , Blumberg Jeffrey B. , Lapsley Karen G. , Jenkins David J. A. 
Published: June 2021

Background: Nut consumption is associated with a reduced risk of coronary heart disease (CHD). Almonds, in addition to their cholesterol‐lowering properties, have been shown to reduce oxidized LDL concentrations. However, their effect on other markers of lipid peroxidation is unknown.Methods: Twenty seven men and women with hyperlipidemia consumed 3 iso‐energetic (mean 423 kcal/d) supplements as part of their therapeutic diets for 1 month each. Supplements consisted of full‐dose almonds (73±3g/d), half‐dose almonds plus half‐dose muffins and full‐dose muffins. Subjects were assessed at wks 0, 2 and 4.Results: At 4 wks, the full‐dose almonds significantly reduced serum concentrations of malondialdehyde (MDA) (P=0.040) and creatinine‐adjusted urinary isoprostane output (P=0.026) compared to the full‐dose muffins. No effect was seen in serum levels of α‐ or γ‐ tocopherol, adjusted or unadjusted for total cholesterol.Conclusion: Almond consumption significantly decreased oxidative damage to 2 additional biomarkers of lipid peroxidation, serum MDA and urinary isoprostanes, further supporting our previous finding that almonds reduced the oxidation of LDL. This provides a further mechanism, in addition to cholesterol‐lowering, that may account for the reduction in CHD risk associated with nut consumption.Funding support: Almond Board of California