bluuebunny/crossref_metadata_2025_split huggingface dataset:
A natural product composition targeting oxidative stress induced mitochondrial dysfunction in Alzheimer's Disease
Authors: Bhaskar Manju , Chintamaneni Meena 
Published: June 2021

Mitochondria regulates cellular metabolism and apoptosis. Oxidative stress induced mitochondrial dysfunction, appears to play a role in the pathogenesis of Alzheimer's disease. Natural antioxidants have been known to play an important role in alleviating the deleterious effects induced by free radicals by blocking the initiation and propagation of oxidizing chain reactions. Hence, the study hypothesizes the effect of natural product composition (combinatorial extract of Eclipta alba, Morinda pubescens and Withania somnifera) on restoring the mitochondrial functional capacity and mitochondrial enzyme levels. The individual and combinatorial methanolic extracts of dried whole plants of Eclipta alba (MEEA), dried fruits of Morinda pubescens (MEMP) and dried roots of Withania somnifera (MEWS) and MECE were prepared. The extracts were screened for in vitro antioxidant activity by DPPH assay. A rodent behavioural model to assess the effect of the extracts on short term memory was performed subsequent to scopolamine hydrobromide induced amnesia and oxidative stress. The brain homogenates from these rodents were subjected to screening in vivo antioxidaint activity using a battery of assays. The effect of extracts on restoring mitochondrial functional capacity (using MTT assay) and the levels of key mitochondrial enzymes succinate dehydrogenase and isocitrate dehydrogenase; was performed using synaptosomal fractions prepared from rodent brain samples.MEEA, MEMP, MEWS and MECE compared with ascorbic acid exhibited 50% scavenging effect at 69.34 μg/ml, 72.19 μg/ml, 65.84 μg/ml, 45.09μg/ml and 57.64 μg/ml, respectively by DPPH assay. Pretreatment with MEEA, MEMP and MEWS at the doses 50,100 and 200 mg/kg and MECE at 50 and 100mg/kg for 8 days followed by scopolamine hydrobromide treatment significantly (p<0.001) improved the antioxidant defense system, the mitochondrial functional capacity and mitochondrial enzyme levels.The natural product composition strengthened the endogenous antioxidant defense system, restored the mitochondrial functional capacity and enzyme levels. Hence, it has a potential neuroprotective role in Alzheimer's disease which needs to be investigated further in a clinical setting.Support or Funding InformationNMIMS UniversityThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Development of a Novel Radioligand for Characterization of the Mas Receptor for Angiotensin 1–7
Authors: Speth Robert Charles , Pang Hong Wang , Neagra Christopher T. , Bergoine Samantha , Linares Andrea , Stoyell‐Conti Filipe F. 
Published: June 2021

It is well established that Mas (NP_002368) is the receptor for angiotensin 1–7 (Ang 1–7), however, to date, no published studies have characterized Mas receptor radioligand binding in tissue membrane preparations. Our laboratory has repeatedly failed to reliably demonstrate high affinity, saturable binding of 125I‐Ang 1–7 in liver, kidney, brain and testes membrane preparations from both rats and mice. While the presence of a single iodine‐125 molecule on the tyrosine of Ang II does not impair its binding to the AT1 and AT2 receptors, it is not known whether the presence of an iodine‐125 molecule on the tyrosine of Ang 1–7 is equally innocuous. To begin to address this question, we prepared a novel analog of Ang 1–7: Tyr0‐Ang 1–7, to provide an alternate site for radioiodination of Ang 1–7. Tyr0‐Ang 1–7 was radioiodinated using the chloramine T procedure of Hunter and Greenwood (1962) with a 7 times excess of peptide to iodine to minimize di‐iodination of the peptide. Two radioiodinated peaks, presumed to be mono125I‐Y0‐Ang 1–7 and mono125I‐Y4‐Ang 1–7, were resolved from the uniodinated peptide peak by HPLC (C18 reverse phase column, 14.5% acetonitrile: triethylamine phosphate, pH 3.0 isocratic mobile phase). Saturation and competition radioligand binding assays were run for each peak using rat liver membrane preparations in the presence and absence of 10 μM Ang 1–7. While the identity of the early and late 125I‐Y0‐ Ang 1–7 peaks has not yet been established, preliminary studies indicate that both 125I‐Y0‐Ang 1–7 peaks displayed high affinity, saturable binding to rat liver membranes: early peak: KD = 7.7±2.3 nM, BMAX = 3.3±0.72 fmol/mg wet weight; and late peak KD = 11±2, BMAX = 3.6±0.4 fmol/mg wet weight. Competition binding assays run using the late peak 125I‐Y0‐Ang 1–7 revealed IC50's of 32±15 nM for Ang 1–7 and 15 ± 9.6 nM for Y0‐Ang 1–7. Comparison of the ability of a variety of Ang peptides to compete for late peak 125I‐Y0‐Ang 1–7 binding at a 10 μM concentration gave a rank order of Ang 1–7>Ang 3–7>Ang IV>Ang III>Ang 2–7>Ang II>Ang I. These results suggest that addition of a tyrosine at the amino terminus of Ang 1–7 may increase its binding affinity for Mas and that the presence of an iodine‐125 on either Y0 or Y4 of Ang 1–7 does not preclude high affinity saturable binding to Mas.Support or Funding InformationThis work was supported by the Cardiovascular Neuroscience Fund, Nova Southeastern University and the Peptide Radioiodination Shared Resource, Georgetown University.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Loss of Caveolin‐3 (Cav‐3) Promotes G‐protein‐regulated Matrix Metalloprotease 14 (MMP14) Activation in the Aged Heart
Authors: Haushalter Kristofer J. , Overland Aaron C. , Patel Hemal H. , Insel Paul A. 
Published: June 2021

Age‐associated cardiovascular disease significantly correlates with morbidity and mortality worldwide; therefore, investigation of cellular signaling pathways in the heart that change with age may help identify novel therapeutic strategies for mitigating the progression of cardiovascular pathologies. Our lab has uncovered a membrane‐delimited receptor transactivation pathway in the heart, wherein G‐protein coupled receptors (GPCRs) signal via heterotrimeric G‐proteins to activate membrane‐tethered matrix metalloprotease 14 (MMP14/MT1‐MMP) and consequently induce “shedding” of membrane‐bound receptor ligands (J Biol Chem 290: 9941‐7). Specifically, G‐protein‐regulated MMP14 releases heparin‐binding EGF‐like growth factor (HB‐EGF), which then triggers activation of epidermal growth factor receptor (EGFR) signaling. We hypothesized that the components of this mechanism are compartmentalized within caveolar lipid raft domains (i.e. cholesterol‐rich membranes containing caveolin‐1 (Cav‐1) and caveolin‐3 (Cav‐3) isoforms), wherein co‐localization with caveolin proteins serves to repress MMP14 enzymatic activity. Furthermore, we hypothesized that age‐dependent loss of Cav‐3 in the heart increases MMP14 activity and thereby alters the signaling pathway to contribute to deleterious cardiac aging phenotypes. We thus sought to compare changes in G‐protein‐regulated MMP14 activity and subsequent activation of HB‐EGF/EGFR signaling in membrane fractions isolated from cardiac myocytes (CMs) and cardiac fibroblasts (CFs) of young (2–3 month) and aged (18–21 month) mice, with or without transgenic CM‐specific overexpression of Cav‐3 (i.e., Cav‐3 OE), to determine if preserved Cav‐3 expression prevents or lessens harmful age‐associated membrane signaling. We observed approximately a two‐fold increase of MMP14 activity in membranes from CMs of aged wild‐type (WT) mice compared to young controls (p< 0.05). Immunoblot analysis of buoyant fractions isolated by differential centrifugation of cardiac tissue in a discontinuous sucrose density gradient confirmed that MMP14, G‐proteins, HB‐EGF, and EGFR co‐localize with caveolin protein isoforms in lipid rafts. Work in progress will test if co‐localization of these proteins is reduced in aged wild‐type (WT) animals but not in Cav‐3 OE animals, and if MMP14 and Cav‐3 co‐immunoprecipitate (co‐IP) within lipid raft domains and thus form a functional signaling module that is disrupted in aged WT subjects but remains intact in Cav‐3 OE mice. Taken together, the results suggest that GPCR transactivation of EGFR and regulation by signaling components in caveolar lipid rafts may be a feature of membrane signaling that is altered in the aged heart.Support or Funding InformationSupported by NIH grants R21AG053568 and R21AG52914.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Dual Soluble Epoxide Hydrolase (sEH)/Fatty Acid Amide Hydrolase (FAAH) Inhibitors with Improved Potency Towards Rodent Species
Authors: Kodani Sean David , Hwang Sung Hee , Morisseau Christophe , Hammock Bruce Dupree 
Published: June 2021

Soluble epoxide hydrolase (sEH) and fatty acid amide hydrolase (FAAH) are therapeutic targets that are independently known to regulate pain. Concurrent inhibition of these two targets is known to be synergistic at reducing pain; thus, we have sought to design dual inhibitors that leverage this synergy in a potent small molecule. Previous efforts have led to very potent and selective inhibitors that target human species but are poorly active on rodent enzymes. In the current work, we attempted an alternative approach towards inhibitor design that was intended to be more potent on rodent enzyme. The approach modified the FAAH inhibitor URB597 (mouse IC50 = 11 nM) to include sEH pharmacophores leading to two new inhibitors: C‐14 (mouse FAAH IC50 = 0.27 nM, mouse sEH IC50 = 68 nM) and C‐20 (mouse FAAH IC50 = 4.4 nM, mouse sEH IC50 = 1.3 nM). C‐20 is 320‐fold and 15‐fold more potent on mouse FAAH and sEH, respectively, than our previous series of dual sEH/FAAH inhibitors. Relative to URB597, these inhibitors had a higher selectivity ratio towards other serine hydrolase; however, caution is required in their application to prevent confounding results. Future studies will test their therapeutic potential in rodent models of pain and other diseases.Support or Funding InformationThis work was supported by the National Institute of Environmental Health Sciences grant R01 ES002710 and the National Institute of Environmental Health Sciences Superfund Research Program grant P42 ES004699. SDK was supported by a NIGMS‐funded Pharmacology Training Program (T32GM099608).This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
In Vitro and In Vivo Metabolism of Soluble Epoxide Hydrolase Inhibitor 1‐ Trifluoromethoxyphenyl‐3‐(1‐propionylpiperidin‐4‐yl) Urea (TPPU)
Authors: Wan Debin , Yang Jun , McReynolds Cindy B. , Wagner Karen M. , Barnych Bogdan , Morisseau Christophe , Sun Jia , Hwang Sung Hee , Hammock Bruce D. 
Published: June 2021

Epoxy fatty acids (EpFAs) are highly potent lipid mediators, formed by cytochrome P450 (CYP450) from polyunsaturated fatty acids. In living organisms, they will be rapidly metabolized by soluble epoxide hydrolase (sEH) to these 1,2‐diol metabolites. A still growing body of evidence suggests that the stabilization of EpFAs by inhibition of sEH has effect of anti‐inflammatory, analgestic, antihypertension and so on. Therefore, sEH inhibitors of high potency are designed for targeting sEH for disease treatment. Among them, 1‐trifluoromethoxyphenyl‐3‐ (1‐propionylpiperidine‐4‐yl)urea (TPPU) of high potency (IC50 of HsEH, 0.6 nM) is the most promising drug. However, the drug metabolism of TPPU has not been studied. Nowadays, drug metabolism has become essential consideration for the safe and efficacious use of drug in human. Therefore, we in this study reported the comprehensive metabolic profiling of TPPU by in vitro and in vivo studies. A developed sensitive liquid chromatography–mass spectrometry (LC‐MS) method was used for identify all these phase I and phase II metabolites of TPPU. Our results indicated three major metabolic pathways of TPPU from phase I metabolism, and one from phase II metabolism.Support or Funding InformationNIEHS grant R01ES002710 and NIEHS Superfund Research Program P42 ES004699 (to B.D.H.), the West Coast Metabolomics Center at UC Davis (NIH/NIDDKU24DK097154) (to B.D.H.) and NIH grant R01 AG051618 (to J. O.)This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
A Dual‐Inhibitor of Soluble Epoxide Hydrolase and p38 Kinase Alleviating Tau Hyperphosphorylation and Amyloid Neurotoxicity for Potential Treatment of Neuroinflammation in Alzheimer's Disease
Authors: Liang Zhibin , Morisseau Christophe , Hwang Sung Hee , Hammock Bruce D. , Li Qing X. 
Published: June 2021

Alzheimer's disease (AD) is the most common dementia that cannot be prevented, cured or even slowed. Neuroinflammation associated with tau hyperphosphorylation and amyloid toxicity is a major hallmark in AD. Soluble epoxide hydrolase (sEH) and p38 kinase are therapeutic targets involving in inflammatory signaling. Development of selective inhibitors to modulate both sEH and p38 kinase is an attractive strategy for AD. We herein studied a potent and blood‐brain barrier permeable sEH inhibitor, 1‐(1‐propanoylpiperidin‐4‐yl)‐3‐[4‐(trifluoromethoxy)phenyl] urea (TPPU) (half maximum inhibition concentration, IC50, 0.64 nM), on neuroprotection in a human AD neuronal model. TPPU effectively alleviates tau hyperphosphorylation and amyloid neurotoxicity in vitro with a half maximum effective concentration (EC50) value of 49 nM. In vitro kinase selectivity profiling indicated that TPPU is a specific p38β kinase inhibitor with an IC50 value of 0.27 μM. The results suggested that TPPU shows a synergistic effect of neuropharmacology through a dual inhibition of sEH and p38. Additional knowledge of TPPU on the neuroinflammatory protection against tau and amyloid pathologies warrants further investigation.Support or Funding InformationThis work was supported in part by the NIH National Institute on Minority Health and Health Disparities grant 8G12MD007601.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Advancing Soluble Epoxide Hydrolase Inhibitors for the Treatment of Osteoarthritis in Companion Animals.
Authors: McReynolds Cindy , Hwang Sung Hee , Yang Jun , Wagner Karen , Schmidt William K. , Hammock Bruce 
Published: June 2021

Soluble epoxide hydrolase inhibitors (sEHI) stabilize biologically active lipid metabolites responsible for regulating homeostatic biological processes. Over the past 20 years, researchers at the University of California at Davis synthesized a large chemical library of potent sEHIs to elucidate the role of this enzyme in biological systems. These chemical inhibitors helped identify analgesic effects of inhibiting the sEH enzyme. Further characterization of safety, enzyme potency and efficacy in mice, rats and dogs identified compound, EC1728, as a lead compound for translation into clinical development for the treatment of painful conditions, such as osteoarthritis.Data will be presented to provide an overview of the screening results that led to the selection of EC1728 for use in companion animals, as well as the results of the initial efficacy study in dogs. To assess efficacy, EC1728 was tested in a naturally occurring arthritis model. Aged beagles (8 per group) with naturally occurring arthritis confirmed by radiographic score were used in this study. Two additional animals were included in a satellite group to measure pharmacokinetic parameters. Dogs were treated once daily with an oral dose of sEHI for five days. Pain measurements were based on an observational questionnaire administered by a blinded clinician that assessed both pain and function. After five days, EC1728 significantly reduced cumulative pain at a dose of 5 mg/kg compared to vehicle controls. Pharmacokinetic evaluation showed concentrations exceeding the enzyme potency in both plasma and synovial fluid. These results provide proof of concept that EC1728 is efficacious in treating osteoarthritis in dogs.EC1728 is a non‐NSAID, non‐opioid compound targeting a novel mechanism of action. Considering these positive efficacy results and good safety profile, as well as the selective potency of inhibiting the sEH enzyme, EC1728 is being developed for use as a safer alternative for the treatment of osteoarthritis in companion animals.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Kinetics of Letrozole Metabolism by Cytochrome P450 3A4: Modulation and Fitting to Non‐Michaelis Menten Models
Authors: Colson Ryan Patrick , Heers Hayley , Chan Jeannine , Harrelson John 
Published: June 2021

Variable blood plasma concentration is an issue for many drugs, including letrozole, which can contribute to toxicity or sub‐effective dosing levels. There is evidence that letrozole is primarily metabolized by CYP2A6 however, CYP2A6 genetic variation only explains a portion (about 30%) of the variability in letrozole plasma concentrations. We hypothesized that CYP3A4 may play a larger role in letrozole metabolism than the current evidence suggests due to the influence of multiple ligand binding and the observation of non‐Michaelis‐Menten kinetic plots. The kinetics of letrozole metabolism by CYP3A4 were analyzed in the presence and absence of ketoconazole, a CYP3A4 modulator, and fitted to multiple ligand binding functions as well as the Michaelis‐Menten model. Further, the time‐dependent inhibition parameters of CYP2A6‐mediated letrozole metabolism were measured in the presence of the CYP2A6‐specific inactivator, trans‐cinnamic aldehyde (tCA). While the Eadie‐Hofstee plot for CYP3A4‐mediated letrozole metabolism was ambiguous, curve fitting showed the Michaelis‐Menten model appropriately characterized metabolism in the absence of ketoconazole (KM: 142+/−23.0 μM, Vmax: 13.0+/−1.44 pmol/nmol/min), suggesting a single ligand bound to the enzyme. A biphasic model most closely modeled letrozole metabolism in the presence of ketoconazole (KM1: 4.71+/−4.55 μM KM2: 513+/−164 μM, Vmax1:0.525+/−0.392 Vmax2: 30.9+/−7.60 pmol/nmol/min) and this was also reflected in the Eadie‐Hofstee plot, which was clearly biphasic; this supports a mechanism involving multiple‐ligand binding. TDI analysis of tCA revealed less effective inhibition of CYP2A6‐mediated letrozole metabolism by tCA (KI: 136 μM, kinact: 0.019 min−1) as compared to CYP2A6‐mediated coumarin metabolism. Together, these results suggest that CYP3A4 may contribute to variability in letrozole metabolism especially in the presence of an effector molecule (i.e., ketoconazole) since the value of KM1 is much closer to the letrozole plasma concentrations observed clinically than the KM value observed in the absence of an effector.Support or Funding InformationFunding from National Institute on Drug AbuseThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Tumor Suppressor Alpha‐arrestin ARRDC3 Controls GPCR Signaling and Breast Cancer Invasion
Authors: Pan Wen An , Arakaki Aleena , Trejo JoAnn 
Published: June 2021

Triple negative breast cancer (TNBC) is an aggressive subtype of breast cancer with poor prognosis and lacks druggable targets. The development of chemotherapy resistance substantially accounts for the high recurrence and death of TNBC patients. Therefore, understanding how TNBC acquires chemoresistance will provide an opportunity to identify new target therapies. G protein‐coupled receptors (GPCR) are the largest family of FDA‐approved drugs but remain overlooked in cancer therapy. Substantial evidence indicates that dysregulated GPCR signaling drives cancer initiation and progression, this is particularly relevant for protease‐activated receptor‐1 (PAR1). However, how PAR1 signaling is dysregulated and confers chemoresistance in aggressive cancers is poorly understood. Arrestin‐domain containing protein 3 (ARRDC3) is a newly identified tumor suppressor in breast cancer and its expression is lost or suppressed in the basal‐like breast cancers, which constitutes the majority of TNBC. Whether and how ARRDC3 play a role in PAR1 signaling and impacts chemoresistance of breast cancer is unclear. The study objective is to address the link between the ARRDC3 and PAR1 signaling and breast cancer chemoresistance. PAR1 is a promising drug target for breast cancer and its expression is correlated with high tumor grade and poor prognosis in breast cancer patients. PAR1 is irreversibly activated by thrombin and its overexpression is sufficient to promote neoplastic transformation and essential for breast cancer metastasis in vitro and in vivo. In invasive breast carcinomas, PAR1 signals constitutively due to a defect in lysosomal trafficking and promotes invasiveness. We hypothesize that ARRDC3 represses PAR1 signaling and chemoresistance in TNBC cells. In this study, we used a lentiviral based ARRDC3 doxycycline‐inducible (pSLIK‐ARRDC3) system in TNBC lines to examine the role and mechanism by which ARRDC3 and PAR1 signaling contribute to chemoresistance. Here we report that ARRDC3 and PAR1 expression are inversely correlated in luminal versus basal‐like invasive breast carcinoma and in patient tissue samples. Activation of PAR1 promotes chemoresistance, while ARRDC3 expression re‐sensitizes cells response to chemotherapy agents. Mechanistically, ARRDC3 specifically represses the magnitude of endosomal PAR1‐induced p38 mitogen‐activated protein kinases (MAPK) signaling but has no effect on extracellular signal‐regulated kinase‐1,2 (ERK1,2) in pSLIK‐ARRDC3 MDA‐MB‐231 cells. In conclusion, our study suggests that PAR1 may be a therapeutic target for attenuation of chemoresistance in ARRDC3‐deficient TNBC patients.Support or Funding InformationThis work is funded by NIH R01 GM090689‐05 and UC Tobacco‐related Disease Research Program High Impact Pilot Award 26IP‐0050This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.