bluuebunny/crossref_metadata_2025_split huggingface dataset:
Linkage between hypothalamic homeostatic and midbrain motivation circuits and habenula enabling sex steroid modulation of motivation and behavior
Authors: Zhang Limei , Hernández Vito S , Emery Andrew C , Eiden Lee E 
Published: June 2021

It is well‐established that the lateral habenula (LHb) plays a key role in integrating a variety of neural circuits associated with reward and aversive behaviors, yet there is limited information about how neuronal circuits within the LHb might serve to coordinate motivational, hormonal and homeostatic states to elicit environmentally appropriate behaviors.We have identified a population of phenotypically GABAergic cell type in the medial division of the LHb (LHbM) that is apparently also endowed with estrogen responsivity, i.e., cells express Esr1 mRNA, and are immunopositive for ERα. These neurons express receptors for vasopressin, serotonin, dopamine and orexin, and project (as identified by in vivo juxtacellular labeling) both locally within LHb and to midbrain cell groups including those in dorsal raphe and impingent upon ventral tegmental area (VTA). They also appear to receive afferents from midbrain reward (dopamine and serotonin) and hypothalamic water and energy homeostasis (vasopressin and orexin) cell groups: these afferents are excitatory (VGLUT2‐expressing) and capable of converting testosterone to estrogen (express aromatase, or estrogen synthase at both the soma and the axon terminals). We have also demonstrated dynamic changes in LHbM VGAT+ cell density that are dependent upon gonadal functional status, and closely correlate with changes in hormone‐dependent vasopressinergic input, and with motivational behavior in response to predator and forced swim stressors.These findings provide a neurochemical and neuroanatomical basis for convergent projecting pathways to LHbMC that employ a localized neurosteroid signaling mechanism to convey altered homeostasic and gonadal hormone status to habenular output controlling motivated behaviors.Magnocellular vasopressinergic neurons of the paraventricular nucleus (PVN) have been observed to send projections not only to the lateral habenula (Zhang et al., 2016) but also to the central nucleus of the amygdala (Hernández et al., 2016). As for the habenular projections, vasopressinergic terminals in amygdala arising from cell bodies in PVN synapse upon GABAergic neurons, and are involved in the linkage of water and thirst homeostatic balance to anxiety and stress coping (Hernández et al., 2016). We are currently examining whether or not vasopressinergic projections to the lateral habenula and to the central amygdala are the same, or distinct neuronal sub‐populations, and whether or not amygdalar target neurons, like those in lateral habenula, are endowed with estrogen responsivity as well.Support or Funding InformationSupported by: CONACYT‐CB‐238744 (LZ), PAPIIT‐IN216918 (LZ) and MH002386 (LEE).This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Genetic Missense Variants at the EGLN1 Locus Associated with High‐Altitude Adaptation in Tibetans are Rare in Andeans
Authors: Lawrence Elijah S. , Heinrich Erica C. , Wu Lu , Villafuerte Francisco C. , Simonson Tatum S. 
Published: June 2021

High‐altitude populations have been challenged by chronic hypoxia for many generations and demonstrate some of the most rapid evolution observed in humans. Genome‐wide scans have brought to light numerous hypoxic‐response candidate genes that are associated with distinct traits in these populations. One example is EGLN1, which shows signals of selection in Tibetan and Andean populations and has been linked to hemoglobin concentration in Tibetans living at high altitude. EGLN1 encodes the hypoxia‐inducible factor (HIF) prolyl hydroxylase 2 (PHD2) protein, which serves as an oxygen‐sensitive regulator of HIF transcription factor activity. We examined the frequencies of two single nucleotide polymorphisms (SNPs) (rs186996510, rs12097901) in the first exon of EGLN1, previously identified at high frequencies and having a gain‐of‐function effect in Tibetans, in a cohort of Quechua Andeans resident at high altitude and individuals of Himalayan (Tibetan, Nepali) ancestry resident at sea level. The minor C allele of rs186996510 is rare among Andeans (0.95%; 1/105) and Nepalese (5.9%; 1/17) but present in 50% (3/6) of Tibetans (X2=36.6, p<0.0001). The minor G allele of rs12097901 was found at 6.6% (7/106) in Andeans, 11.8% (2/17) in Nepalese, and 50% (3/6) in Tibetans (X2=12.8, p<0.002). Two female sea‐level, Tibetan participants with the minor C allele rs186996510 both had significantly lower hematocrit values than the other sea‐level women (F(1,7)=8.8, p=0.025). These genomic differences suggest that despite the identification of an adaptive genetic signal at this locus in both Andean and Tibetan populations, the EGLN1 variants previously reported in Tibetans are very rare in Andeans.Support or Funding InformationThis study was supported by an NIH NRSA Individual Postdoctoral Fellowship (Parent F32) to ECH (F32HL131218), NIH TL1TR001443 to LW, a University of California, San Diego Ledell Family Undergraduate Research Scholarship award for Science and Engineering to ESL, and NIH R00HL118215 and American Physiological Society Giles F. Filley Memorial Award to TSS. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH. The UPCH team was supported by a Wellcome Trust PHTM grant (107544/Z/15/Z) to FCV.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The Pharmacological Characterization of Riluzole on Anxiety and Memory
Authors: Rossi Grace , Rahyab Marjon , Hindieh Jennifer , Nuzzo Arianna , Visquerra Vanessa , Gelles Janine 
Published: June 2021

Riluzole is a novel medication that is presently investigated in the field of ALS research since it is a chemical that is known to promote plasticity. The present study plans to investigate the effects of Riluzole on memory in the PTSD model of anxiety in CD‐1 mice. Prior to any manipulation, all subjects were placed on an elevated plus maze (EPM) for 5 minutes in order to obtain baseline data for anxiety. After baseline data was collected, stress was induced in all animals by individually exposing to an aggressor for 5 minutes for 7–10 consecutive days. Mice were reexamined for anxiety by returning to them on the EPM. Continuing further, only anxious mice were used in the study. Twenty mice were given Riluzole (5mg/kg,i.p). All mice were tested on a spatial memory task (the Morris Water Maze) on the 10th day of exposure to the bully mouse. The goal was to investigate the effects of Riluzole on spatial memory after a fear‐provoking experience (exposure to an aggressor mice). After the 10th day of exposing the mice to aggressor mice all mice had significantly higher anxiety levels. Riluzole had limited effects on spatial memory in the anxiety mice. Empirical evidence suggests male and female's spatial memory differ. Further investigation will examine if the findings generalize to female mice as well.Support or Funding InformationThe present study was supported by LIU‐Post Monetary Grant.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Synthesis, Docking Studies and Biological Evaluation of Triazole‐Thiazolidinedione/Rhodanine Hybrids Targeting Cyclooxygenase‐2, 5‐Lipoxygenase and Peroxisome proliferator‐activated receptor
Authors: Alaaeddine Rana , Elzahhar Perihan , Belal Ahmed , Nassra Rasha , Ibrahim Tamer , Wallner Nadja , Knape Tilo , Von Knethen Andreas , El‐Yazbi Ahmed F. 
Published: June 2021

Inflammation is associated with different clinical conditions including rheumatoid disorders and multiple sclerosis. Recently, inflammation has been linked to metabolic diseases, such as diabetes. In addition to their antidiabetic effect, thiazolidinediones (TZDs), through PPARγ transactivation, are also known to negatively control transcriptional pathways that are critical for the synthesis of pro‐inflammatory molecules. Moreover, selective COX‐2 inhibitors serve as effective anti‐inflammatory agents with minimal GIT side effects; however, only blocking COX‐2 shunts the inflammatory pathways towards more activity of LOX, and hence blocking both COX‐2 and LOX would provide safer and more effective anti‐inflammatory activity. In our search for multi‐targeting anti‐inflammatory leads, we adopted a hybrid pharmacophore approach to design and synthesize some novel triazolyl‐thiazolidinedione/rhodanine hybrids as potential simultaneous COX‐2/LOX inhibitors and PPARγ agonists. Ten of these compounds demonstrated significant in vitro COX‐2 and 15‐LOX inhibitory activities, four of which exhibited high in vitro tissue glucose uptake. These drugs revealed comparable nuclear PPARγ translocation to that of pioglitazone and luciferase activity. PMA‐induced macrophage differentiation assay conducted on THP‐1 cells demonstrated similar or exceeding potency than diclofenac. This translated to in‐vivo formalin‐induced rat paw edema bioassay where the selected drugs showed an anti‐inflammatory activity. The pharmacological data were coherent with the in silico results. Accordingly, this series of compounds may represent promising leads to pursue as potential simultaneous COX‐2/LOX inhibitors and PPARγ agonists for the management of diabetes and other inflammatory disorders.Support or Funding InformationPartially supported by AUB MPP fund #320148This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
A Genetically‐Encoded Fluorescent Assay to Detect Drug Toxicity and Genetic Stress in Living Cells
Authors: Harlen Kevin M , Hughes Thom , Quinn Anne Marie 
Published: June 2021

We have created a genetically‐encoded fluorescent biosensor to detect chemically and genetically induced stress in living cells. Identifying stressed cells long before they enter the apoptotic pathway opens a therapeutic window between cell stress and death. Further, the biosensor can also be used to identify toxic side effects of drugs or lead compounds.The sensor co‐opts one pathway of the unfolded protein response as the driving mechanism to detect cell stress. Non‐canonical splicing of an intron derived from the XBP1 protein shifts into frame a bright green fluorescent protein, which indicates the onset of cell stress. Importantly, this intron is only spliced upon activation of endoplasmic reticulum stress or the unfolded protein response. Ratioing this signal with a constitutively expressed red fluorescent protein signal allows real‐time monitoring of cells stress and protein production. We have also engineered this biosensor to be reversible, allowing detection of the onset of stress as well as the amelioration of stress. This positions the biosensor to be used for testing compounds that may relieve cell stress.We applied this assay to examine the toxic side effects of cardiac glycosides and doxorubicin on cardiomyocytes derived from human induced pluripotent stem cells. Drug toxicity was detected within 24 hours of treatment in a dose dependent manner. The cardiac glycosides induced cell stress mediated through either the unfolded protein response or endoplasmic reticulum stress while doxorubicin, which inhibits the XBP1 pathway, mainly displayed cytotoxic effects. We next used this assay to detect cellular stress induced by genetic mutations. Many neurological diseases, such as Retinitis Pigmentosa, Parkinson's and Amyotrophic lateral Sclerosis (ALS), are associated with protein folding or aggregation defects which induce high levels of cellular stress. This live‐cell stress assay is capable of monitoring cellular stress induced by mutations causing Retinitis Pigmentosa (Rhodopsin P23H mutation) and ALS (SOD G86R mutation) in less than 24 hours after mutant gene expression.Lastly, multiplexing this cell stress assay with other live‐cell assays detecting second messenger signaling revealed cells experiencing either chemically or genetically induced stress had altered basal levels of cytoplasmic Ca2+ and cAMP as well as a blunted Ca2+ signaling response. Together these studies demonstrate the broad utility of this newly developed live‐cell assay for cell stress and toxicity for use in automated screening of drugs and compounds, determination of adverse drug toxicity, and analysis of disease mechanisms.Support or Funding InformationSupported by ASEE/NSF Small Business Postdoctoral Research Diversity Fellowship Program NSF Award IIP‐1552305This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Molecular dynamics simulations reveal that tyrosine nitration leads to destabilization of CYP2B6 secondary structure
Authors: Wilderman Ross , Lee Choon‐Myung , Morgan Edward 
Published: June 2021

Post‐translational modification of proteins is a major mechanism for the control of cellular machinery. Nitric oxide stimulates ubiquitination and proteosomal degradation of CYP2B6 and CYP51, which is hypothesized to be due to tyrosine nitration. Alanine scanning of CYP2B6 residues indicated that Tyr190Ala, Tyr317Ala, and Tyr380Ala partially protected the enzyme from proteasomal degradation. Alignment of CYP2B sequences from the Cytochrome P450 Homepage revealed that residues 190, 317, and 380 are absolutely conserved tyrosines. Other residues that are tyrosine in CYP2B6 have less conservation across the aligned sequences. Molecular dynamics simulations of CYP2B6 wild‐type, Tyr‐to‐Ala mutants, and Tyr‐to‐3‐nitrotyrosine (NIY) mutants were performed. For most mutants, the protein was stable throughout the simulation period. However, CYP2B6 Tyr235Niy simulations collapsed due to the G‐helix unraveling. Simulation of this mutant was successful if the stabilizing mutations Tyr226His and Lys262Arg from the CYP2B6 crystallization construct were introduced into the protein. In general, mutant proteins behaved similarly to wild‐type CYP2B6 as measured by bond angles and lengths. However, mutating CYP2B6 decreased the solvent accessible surface area and volume while increasing the density of the protein across the simulation. While introduction of alanine did not have large effects on protein secondary structure, NIY caused large changes in protein secondary structural elements close to the residue in space. Furthermore, introduction of NIY at any residue decreased the magnitude of residue‐residue interaction correlations within CYP2B6. Overall, tyrosine nitration leads to secondary structure destabilization and compaction of CYP2B6. These results provide insight into effects of CYP2B6 tyrosine nitration that may lead to proteosomal degradation.Support or Funding InformationNIEHS Grant # 003619This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Deficiency of N‐Acetyltransferase Potentiates Isoniazid‐Endobiotics Interactions and Contributes to Isoniazid Hepatotoxicity
Authors: Wang Pengcheng , Li Feng , Lu Jie , Grant Denis M. , Zhong Xiao‐bo , Ma Xiaochao 
Published: June 2021

Isoniazid (INH) is a first‐line anti‐tuberculosis drug, but it causes liver injury frequently. The biochemical basis of INH toxicity in the liver remains elusive. We used an untargeted metabolomic approach to explore the effects of INH on endobiotic homeostasis in mouse liver. We found that overdose of INH resulted in accumulation of multiple endobiotics and INH‐endobiotics conjugates, including long‐chain acylcarnitines, INH‐fatty acid amides, heme, nicotinamide adenine dinucleotide (NAD), and INH‐NAD adduct. Furthermore, we illustrated that overdose of INH depleted vitamin B6 in the liver and blocked vitamin B6‐dependent cystathionine degradation. These results indicate INH can disrupt multiple endobiotics metabolic pathways, which are all critical for hepatocellular functions. Acetylation is the major metabolic pathway of INH and it is mediated by N‐acetyltransferase (NAT). Previous reports showed that slow acetylators have a higher risk of hepatotoxicity than rapid acetylators during INH chemotherapy. We used Nat1/2 (−/−) mice to mimic NAT slow metabolizers. We found that INH acetylation was significantly suppressed in Nat1/2(−/−) mice, whereas INH‐endobiotic interactions were significantly increased. These data demonstrate that deficiency of NAT increases the interactions of INH with endobiotics in the liver, which may in part explains the high risks of INH hepatotoxicity in NAT slow metabolizers.Support or Funding InformationThis work was supported in part by the National Institute of Diabetes and Digestive and Kidney Diseases (DK090305), the National Institute of Allergy And Infectious Diseases (R01AI131983), and the National Institute of General Medical Sciences (GM118367).This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Physiologically based pharmacokinetic modelling of atomoxetine with regard to CYP2D6 genotypes
Authors: LEE SEOK‐YONG , Kim Se‐Hyung , Byeon Ji‐Young , Lee Choong‐Min , Kim Young‐Hoon , Lee Yun Jeong , Jang Choon‐Gon 
Published: June 2021

Atomoxetine is a norepinephrine reuptake inhibitor indicated in the treatment of attention‐deficit/hyperactivity disorder. It is primarily metabolised by CYP2D6 to its equipotent metabolite, 4‐hydroxyatomoxetine, which promptly undergoes further glucuronidation to an inactive 4‐HAT‐O‐glucuronide. Clinical trials have shown that decreased CYP2D6 activity leads to substantially elevated atomoxetine exposure and more adverse reactions. The aims of this study were to analyse the pharmacokinetics of atomoxetine and to develop a pharmacologically based pharmacokinetic (PBPK) model of atomoxetine in different CYP2D6 genotypes. A single 20 mg dose of atomoxetine was given to 19 healthy Korean individuals with CYP2D6*wt/*wt (*wt = *1 or *2) or CYP2D6*10/*10 genotype. Based on the results of this pharmacokinetic study, a PBPK model for CYP2D6*wt/*wt individuals was developed. This model was scaled to those with CYP2D6*10/*10 genotype, as well as CYP2D6 poor metabolisers. We validated this model by comparing the achieved pharmacokinetic parameters with diverse results from the literature. The presented PBPK model describes the pharmacokinetics after single and repeated oral atomoxetine doses with regard to CYP2D6 genotype and phenotype. This model could be utilized for identification of appropriate dosages of atomoxetine in patients with reduced CYP2D6 activity to minimize the adverse events, and to enable personalised medicine.Support or Funding InformationThis research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT, & Future Planning (NRF‐2016R1A2B4007381).This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Mustard analogs of acetylcholine: irreversible partial agonists at Gq‐linked muscarinic receptors
Authors: Ellis John , Elmslie Gwendolynne 
Published: June 2021

Mustard analogs of many receptor ligands have been used to irreversibly label or inactivate receptors. In aqueous solution, mustard groups cyclize to form aziridinium ions that closely mimic quaternary amines. Such a reactive intermediate may therefore bind in the same orientation within the same binding pocket of the receptor that accommodates the related reversible ligand. Once oriented, it is capable of alkylating any of a number of nearby amino acid side chains (including those of cysteine, glutamate, aspartate, and others) and might, in principle, induce irreversible activation of the receptor. However, acetylcholine mustard has been reported by several laboratories to possess agonist activity at muscarinic receptors only until alkylation is achieved, at which point the receptor becomes inactivated. Therefore, we were surprised to find that agonist activity persisted after irreversible binding of acetylcholine mustard and its analog, acetylethylcholine mustard, at Gq‐linked muscarinic receptors (M1, M3, and M5) expressed in CHO cells. The cells were preincubated with cyclized agonist mustards and thoroughly washed prior to assay; the observed responses could be prevented by including atropine in the preincubation phase, but were not inhibited by the presence of atropine in the assay phase. The metabolism of inositol phosphates (IP) was enhanced robustly, though to a lesser degree than that induced by acetylcholine. Acetylethylcholine mustard was less efficacious than acetylcholine mustard, especially at the M5 subtype. For both mustards, the order of efficacy was M1>M3>M5. The most interesting results were obtained measuring the receptor‐stimulated release of labeled arachidonic acid (AA) from intact cells. After preincubation as above, the basal AA release was found to be elevated to a small but significant degree; we have previously shown amiodarone to be a positive allosteric modulator (PAM) at these receptors and inclusion of amiodarone in the assay phase dramatically increased the response of cells that had been preincubated with the agonist mustards. Once again, atropine in the assay itself did not prevent this effect of amiodarone, but atropine in the preincubation phase prevented it completely. At the M1 subtype, the well‐known M1‐specific PAM BQCA enhanced the mustard‐induced activity in a manner similar to that observed for amiodarone. These studies confirm that amiodarone, BQCA, and other ligands investigated act at an allosteric site and suggest that receptors that have been alkylated by acetylcholine mustard and acetylethylcholine mustard do adopt active conformations that can be further enhanced by appropriate allosteric ligands.Support or Funding InformationSupported AG005214 to JEThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.