Smith D

References (11)

Title : Soluble epoxide hydrolase-targeting PROTAC activates AMPK and inhibits endoplasmic reticulum stress - Peyman_2023_Biomed.Pharmacother_168_115667
Author(s) : Peyman M , Barroso E , Turcu AL , Estrany F, Jr. , Smith D , Jurado-Aguilar J , Rada P , Morisseau C , Hammock BD , Valverde A M , Palomer X , Galdeano C , Vazquez S , Vazquez-Carrera M
Ref : Biomed Pharmacother , 168 :115667 , 2023
Abstract : Soluble epoxide hydrolase (sEH) is a drug target with the potential for therapeutic utility in the areas of inflammation, neurodegenerative disease, chronic pain, and diabetes, among others. Proteolysis-targeting chimeras (PROTACs) molecules offer new opportunities for targeting sEH, due to its capacity to induce its degradation. Here, we describe that the new ALT-PG2, a PROTAC that degrades sEH protein in the human hepatic Huh-7 cell line, in isolated mouse primary hepatocytes, and in the liver of mice. Remarkably, sEH degradation caused by ALT-PG2 was accompanied by an increase in the phosphorylated levels of AMP-activated protein kinase (AMPK), while phosphorylated extracellular-signal-regulated kinase 1/2 (ERK1/2) was reduced. Consistent with the key role of these kinases on endoplasmic reticulum (ER) stress, ALT-PG2 attenuated the levels of ER stress and inflammatory markers. Overall, the findings of this study indicate that targeting sEH with degraders is a promising pharmacological strategy to promote AMPK activation and to reduce ER stress and inflammation.
ESTHER : Peyman_2023_Biomed.Pharmacother_168_115667
PubMedSearch : Peyman_2023_Biomed.Pharmacother_168_115667
PubMedID: 37826940
Gene_locus related to this paper: human-EPHX2

Title : Pharmacologic treatment of delirium symptoms: A systematic review - Sadlonova_2022_Gen.Hosp.Psychiatry_79_60
Author(s) : Sadlonova M , Duque L , Smith D , Madva EN , Amonoo HL , Vogelsang J , Staton SC , von Arnim CAF , Huffman JC , Celano CM
Ref : General Hospital Psychiatry , 79 :60 , 2022
Abstract : OBJECTIVE: We conducted an updated, comprehensive, and contemporary systematic review to examine the efficacy of existing pharmacologic agents employed for management of delirium symptoms among hospitalized adults. METHODS: Searches of PubMed, Scopus, Embase, and Cochrane Library databases from inception to May 2021 were performed to identify studies investigating efficacy of pharmacologic agents for management of delirium. RESULTS: Of 11,424 articles obtained from searches, a total of 33 articles (N = 3030 participants) of randomized or non-randomized trials, in which pharmacologic treatment was compared to active comparator, placebo, or no treatment, met all criteria and were included in this review. Medications used for management of delirium symptoms included antipsychotic medications (N = 27), alpha-2 agonists (N = 5), benzodiazepines (N = 2), antidepressants (n = 1), acetylcholinesterase inhibitors (N = 2), melatonin (N = 2), opioids (N = 1), and antiemetics (N = 2). Despite somewhat mixed findings and a relative lack of high-quality trials, it appears that antipsychotic medications (e.g., haloperidol, olanzapine, risperidone, or quetiapine) and dexmedetomidine have the potential to improve delirium outcomes. CONCLUSIONS: Pharmacologic agents can reduce delirium symptoms (e.g., agitation) in some hospitalized patients. Additional double-blinded, randomized, placebo-controlled clinical trials are critically needed to investigate the efficacy of pharmacologic agents for diverse hospitalized populations (e.g., post-surgical patients, patients at the end-of-life, or in intensive care units).
ESTHER : Sadlonova_2022_Gen.Hosp.Psychiatry_79_60
PubMedSearch : Sadlonova_2022_Gen.Hosp.Psychiatry_79_60
PubMedID: 36375344

Title : Combining CDP-choline and galantamine, an optimized alpha7 nicotinic strategy, to ameliorate sensory gating to speech stimuli in schizophrenia - Choueiry_2019_Int.J.Psychophysiol_145_70
Author(s) : Choueiry J , Blais CM , Shah D , Smith D , Fisher D , Labelle A , Knott V
Ref : Int J Psychophysiol , 145 :70 , 2019
Abstract : Neural alpha7 nicotinic acetylcholine receptor (nAChR) expression and functioning deficits have been extensively associated with cognitive and early sensory gating (SG) impairments in schizophrenia (SCZ) patients and their relatives. SG, the suppression of irrelevant and redundant stimuli, is measured in a conditioning-testing (S1-S2) paradigm eliciting electroencephalography-derived P50 event-related potentials (ERPs), the S2 amplitudes of which are typically suppressed relative to S1. Despite extensive reports of nicotine-related improvements and several decades of research, an efficient nicotinic treatment has yet to be approved for SCZ. Following reports of SG improvements in low P50 suppressing SCZ patients and healthy participants with the alpha7 agonist, CDP-choline, this pilot study examined the combined modulatory effect of CDP-choline (500mg) and galantamine (16mg), a nAChR positive allosteric modulator and acetylcholinesterase inhibitor, on SG to speech stimuli in twenty-four SCZ patients in a randomized, double-blind and placebo-controlled design. As expected, in low P50 suppressors CDP-choline/galantamine (vs. Placebo) improved rP50 and dP50 scores by increasing inhibitory mechanisms as reflected by S2P50 amplitude reductions. Results also suggest a moderating role for auditory verbal hallucinations in treatment response. These preliminary findings provide supportive evidence for the involvement of alpha7 nAChR activity in speech gating in SCZ and support additional trials, examining different dose combinations and repeated doses of this optimized and personalized targeted alpha7 cholinergic treatment for SG dysfunction in subgroups of SCZ patients.
ESTHER : Choueiry_2019_Int.J.Psychophysiol_145_70
PubMedSearch : Choueiry_2019_Int.J.Psychophysiol_145_70
PubMedID: 30790597

Title : Efficacy and safety of tiotropium Respimat SMI in COPD in two 1-year randomized studies - Bateman_2010_Int.J.Chron.Obstruct.Pulmon.Dis_5_197
Author(s) : Bateman E , Singh D , Smith D , Disse B , Towse L , Massey D , Blatchford J , Pavia D , Hodder R
Ref : Int J Chron Obstruct Pulmon Dis , 5 :197 , 2010
Abstract : Two 1-year studies evaluated the long-term efficacy and safety of tiotropium 5 or 10 microg versus placebo, inhaled via the Respimat Soft Mist Inhaler (SMI). The two studies were combined and had 4 co-primary endpoints (trough FEV(1) response, Mahler Transition Dyspnea Index [TDI] and St George's Respiratory Questionnaire scores all at week 48, and COPD exacerbations per patient-year). A total of 1990 patients with COPD participated (mean FEV(1): 1.09 L). The mean trough FEV(1) response of tiotropium 5 or 10 microg relative to placebo was 127 or 150 mL, respectively (both P < 0.0001). The COPD exacerbation rate was significantly lower with tiotropium 5 microg (RR = 0.78; P = 0.002) and tiotropium 10 microg (RR = 0.73; P = 0.0008); the health-related quality of life and Mahler TDI co-primary endpoints were significantly improved with both doses (both P < 0.0001). Adverse events were generally balanced except anticholinergic class effects, which were more frequent with active treatment. Fatal events occurred in 2.4% (5 microg), 2.7% (10 microg), and 1.6% (placebo) of patients; these differences were not significant. Tiotropium Respimat SMI 5 microg demonstrated sustained improvements in patients with COPD relative to placebo and similar to the 10 microg dose but with a lower frequency of anticholinergic adverse events.
ESTHER : Bateman_2010_Int.J.Chron.Obstruct.Pulmon.Dis_5_197
PubMedSearch : Bateman_2010_Int.J.Chron.Obstruct.Pulmon.Dis_5_197
PubMedID: 20714373

Title : Functional study of the 830C>G polymorphism of the human carboxylesterase 2 gene - Bellott_2008_Cancer.Chemother.Pharmacol_61_481
Author(s) : Bellott R , Le Morvan V , Charasson V , Laurand A , Colotte M , Zanger UM , Klein K , Smith D , Bonnet J , Robert J
Ref : Cancer Chemother Pharmacol , 61 :481 , 2008
Abstract : PURPOSE: Carboxylesterase 2 (CES2) is involved in the activation of the anticancer drug irinotecan to its active metabolite SN-38. We previously identified a single nucleotide polymorphism (SNP), with an allele frequency around 10%, as possibly involved in enzyme expression (Clin Pharmacol Ther 76:528-535, 2004), which could explain the large individual variation in SN-38 disposition. METHODS: The 830C>G SNP, located in the 5' untranslated region of the gene, was analysed in various DNA samples extracted from: (1) the National Cancer Institute NCI-60 panel of human tumour cell lines; (2) a collection of 104 samples of normal tissue from colorectal cancer patients; (3) blood samples from a population of 95 normal subjects; (4) a collection of 285 human livers. CES2 genotypes were tentatively related to irinotecan cytotoxicity and CES2 expression in the NCI-60 panel; to response to treatment and event-free survival in colorectal cancer patients; and to CES2 expression and catalytic activity in subsets of the human liver collection. RESULTS: No significant relationship was found in the NCI-60 panel between CES2 830C>G genotype and irinotecan cytotoxicity or CES2 expression. No significant relationship was found between CES2 830C>G genotype and the toxicity and therapeutic efficacy (tumour response, event-free survival) of irinotecan in colorectal cancer patients. There was no significant relationship between CES2 830C>G genotype and CES2 expression and catalytic activity determined in a subset of genotype-selected liver samples. CONCLUSION: The 830C>G SNP of CES2 is unlikely to have significant functional consequences on CES2 expression, activity or function.
ESTHER : Bellott_2008_Cancer.Chemother.Pharmacol_61_481
PubMedSearch : Bellott_2008_Cancer.Chemother.Pharmacol_61_481
PubMedID: 17483951
Gene_locus related to this paper: human-CES2

Title : Burkholderia xenovorans LB400 harbors a multi-replicon, 9.73-Mbp genome shaped for versatility - Chain_2006_Proc.Natl.Acad.Sci.U.S.A_103_15280
Author(s) : Chain PS , Denef VJ , Konstantinidis KT , Vergez LM , Agullo L , Reyes VL , Hauser L , Cordova M , Gomez L , Gonzalez M , Land M , Lao V , Larimer F , LiPuma JJ , Mahenthiralingam E , Malfatti SA , Marx CJ , Parnell JJ , Ramette A , Richardson P , Seeger M , Smith D , Spilker T , Sul WJ , Tsoi TV , Ulrich LE , Zhulin IB , Tiedje JM
Ref : Proc Natl Acad Sci U S A , 103 :15280 , 2006
Abstract : Burkholderia xenovorans LB400 (LB400), a well studied, effective polychlorinated biphenyl-degrader, has one of the two largest known bacterial genomes and is the first nonpathogenic Burkholderia isolate sequenced. From an evolutionary perspective, we find significant differences in functional specialization between the three replicons of LB400, as well as a more relaxed selective pressure for genes located on the two smaller vs. the largest replicon. High genomic plasticity, diversity, and specialization within the Burkholderia genus are exemplified by the conservation of only 44% of the genes between LB400 and Burkholderia cepacia complex strain 383. Even among four B. xenovorans strains, genome size varies from 7.4 to 9.73 Mbp. The latter is largely explained by our findings that >20% of the LB400 sequence was recently acquired by means of lateral gene transfer. Although a range of genetic factors associated with in vivo survival and intercellular interactions are present, these genetic factors are likely related to niche breadth rather than determinants of pathogenicity. The presence of at least eleven "central aromatic" and twenty "peripheral aromatic" pathways in LB400, among the highest in any sequenced bacterial genome, supports this hypothesis. Finally, in addition to the experimentally observed redundancy in benzoate degradation and formaldehyde oxidation pathways, the fact that 17.6% of proteins have a better LB400 paralog than an ortholog in a different genome highlights the importance of gene duplication and repeated acquirement, which, coupled with their divergence, raises questions regarding the role of paralogs and potential functional redundancies in large-genome microbes.
ESTHER : Chain_2006_Proc.Natl.Acad.Sci.U.S.A_103_15280
PubMedSearch : Chain_2006_Proc.Natl.Acad.Sci.U.S.A_103_15280
PubMedID: 17030797
Gene_locus related to this paper: burxl-metx , burxl-mhpc , burxl-q13fa9 , burxl-q13ha0 , burxl-q13mn9 , burxl-q13nr6 , burxl-q13ns4 , burxl-q13p13 , burxl-q13p37 , burxl-q13pg5 , burxl-q13ph5 , burxl-q13pw2 , burxl-q13q15 , burxl-q13qw4 , burxl-q13ri3 , burxl-q13ui7 , burxl-q13ul9 , burxl-q13uz6 , burxl-q13vd6 , burxl-q13xg6 , burxl-q146l5 , burxl-q13u43 , parxl-hboh

Title : The DNA sequence and biology of human chromosome 19 - Grimwood_2004_Nature_428_529
Author(s) : Grimwood J , Gordon LA , Olsen A , Terry A , Schmutz J , Lamerdin J , Hellsten U , Goodstein D , Couronne O , Tran-Gyamfi M , Aerts A , Altherr M , Ashworth L , Bajorek E , Black S , Branscomb E , Caenepeel S , Carrano A , Caoile C , Chan YM , Christensen M , Cleland CA , Copeland A , Dalin E , Dehal P , Denys M , Detter JC , Escobar J , Flowers D , Fotopulos D , Garcia C , Georgescu AM , Glavina T , Gomez M , Gonzales E , Groza M , Hammon N , Hawkins T , Haydu L , Ho I , Huang W , Israni S , Jett J , Kadner K , Kimball H , Kobayashi A , Larionov V , Leem SH , Lopez F , Lou Y , Lowry S , Malfatti S , Martinez D , McCready P , Medina C , Morgan J , Nelson K , Nolan M , Ovcharenko I , Pitluck S , Pollard M , Popkie AP , Predki P , Quan G , Ramirez L , Rash S , Retterer J , Rodriguez A , Rogers S , Salamov A , Salazar A , She X , Smith D , Slezak T , Solovyev V , Thayer N , Tice H , Tsai M , Ustaszewska A , Vo N , Wagner M , Wheeler J , Wu K , Xie G , Yang J , Dubchak I , Furey TS , DeJong P , Dickson M , Gordon D , Eichler EE , Pennacchio LA , Richardson P , Stubbs L , Rokhsar DS , Myers RM , Rubin EM , Lucas SM
Ref : Nature , 428 :529 , 2004
Abstract : Chromosome 19 has the highest gene density of all human chromosomes, more than double the genome-wide average. The large clustered gene families, corresponding high G + C content, CpG islands and density of repetitive DNA indicate a chromosome rich in biological and evolutionary significance. Here we describe 55.8 million base pairs of highly accurate finished sequence representing 99.9% of the euchromatin portion of the chromosome. Manual curation of gene loci reveals 1,461 protein-coding genes and 321 pseudogenes. Among these are genes directly implicated in mendelian disorders, including familial hypercholesterolaemia and insulin-resistant diabetes. Nearly one-quarter of these genes belong to tandemly arranged families, encompassing more than 25% of the chromosome. Comparative analyses show a fascinating picture of conservation and divergence, revealing large blocks of gene orthology with rodents, scattered regions with more recent gene family expansions and deletions, and segments of coding and non-coding conservation with the distant fish species Takifugu.
ESTHER : Grimwood_2004_Nature_428_529
PubMedSearch : Grimwood_2004_Nature_428_529
PubMedID: 15057824

Title : Genome sequence of the Brown Norway rat yields insights into mammalian evolution - Gibbs_2004_Nature_428_493
Author(s) : Gibbs RA , Weinstock GM , Metzker ML , Muzny DM , Sodergren EJ , Scherer S , Scott G , Steffen D , Worley KC , Burch PE , Okwuonu G , Hines S , Lewis L , DeRamo C , Delgado O , Dugan-Rocha S , Miner G , Morgan M , Hawes A , Gill R , Celera , Holt RA , Adams MD , Amanatides PG , Baden-Tillson H , Barnstead M , Chin S , Evans CA , Ferriera S , Fosler C , Glodek A , Gu Z , Jennings D , Kraft CL , Nguyen T , Pfannkoch CM , Sitter C , Sutton GG , Venter JC , Woodage T , Smith D , Lee HM , Gustafson E , Cahill P , Kana A , Doucette-Stamm L , Weinstock K , Fechtel K , Weiss RB , Dunn DM , Green ED , Blakesley RW , Bouffard GG , de Jong PJ , Osoegawa K , Zhu B , Marra M , Schein J , Bosdet I , Fjell C , Jones S , Krzywinski M , Mathewson C , Siddiqui A , Wye N , McPherson J , Zhao S , Fraser CM , Shetty J , Shatsman S , Geer K , Chen Y , Abramzon S , Nierman WC , Havlak PH , Chen R , Durbin KJ , Egan A , Ren Y , Song XZ , Li B , Liu Y , Qin X , Cawley S , Cooney AJ , D'Souza LM , Martin K , Wu JQ , Gonzalez-Garay ML , Jackson AR , Kalafus KJ , McLeod MP , Milosavljevic A , Virk D , Volkov A , Wheeler DA , Zhang Z , Bailey JA , Eichler EE , Tuzun E , Birney E , Mongin E , Ureta-Vidal A , Woodwark C , Zdobnov E , Bork P , Suyama M , Torrents D , Alexandersson M , Trask BJ , Young JM , Huang H , Wang H , Xing H , Daniels S , Gietzen D , Schmidt J , Stevens K , Vitt U , Wingrove J , Camara F , Mar Alba M , Abril JF , Guigo R , Smit A , Dubchak I , Rubin EM , Couronne O , Poliakov A , Hubner N , Ganten D , Goesele C , Hummel O , Kreitler T , Lee YA , Monti J , Schulz H , Zimdahl H , Himmelbauer H , Lehrach H , Jacob HJ , Bromberg S , Gullings-Handley J , Jensen-Seaman MI , Kwitek AE , Lazar J , Pasko D , Tonellato PJ , Twigger S , Ponting CP , Duarte JM , Rice S , Goodstadt L , Beatson SA , Emes RD , Winter EE , Webber C , Brandt P , Nyakatura G , Adetobi M , Chiaromonte F , Elnitski L , Eswara P , Hardison RC , Hou M , Kolbe D , Makova K , Miller W , Nekrutenko A , Riemer C , Schwartz S , Taylor J , Yang S , Zhang Y , Lindpaintner K , Andrews TD , Caccamo M , Clamp M , Clarke L , Curwen V , Durbin R , Eyras E , Searle SM , Cooper GM , Batzoglou S , Brudno M , Sidow A , Stone EA , Payseur BA , Bourque G , Lopez-Otin C , Puente XS , Chakrabarti K , Chatterji S , Dewey C , Pachter L , Bray N , Yap VB , Caspi A , Tesler G , Pevzner PA , Haussler D , Roskin KM , Baertsch R , Clawson H , Furey TS , Hinrichs AS , Karolchik D , Kent WJ , Rosenbloom KR , Trumbower H , Weirauch M , Cooper DN , Stenson PD , Ma B , Brent M , Arumugam M , Shteynberg D , Copley RR , Taylor MS , Riethman H , Mudunuri U , Peterson J , Guyer M , Felsenfeld A , Old S , Mockrin S , Collins F
Ref : Nature , 428 :493 , 2004
Abstract : The laboratory rat (Rattus norvegicus) is an indispensable tool in experimental medicine and drug development, having made inestimable contributions to human health. We report here the genome sequence of the Brown Norway (BN) rat strain. The sequence represents a high-quality 'draft' covering over 90% of the genome. The BN rat sequence is the third complete mammalian genome to be deciphered, and three-way comparisons with the human and mouse genomes resolve details of mammalian evolution. This first comprehensive analysis includes genes and proteins and their relation to human disease, repeated sequences, comparative genome-wide studies of mammalian orthologous chromosomal regions and rearrangement breakpoints, reconstruction of ancestral karyotypes and the events leading to existing species, rates of variation, and lineage-specific and lineage-independent evolutionary events such as expansion of gene families, orthology relations and protein evolution.
ESTHER : Gibbs_2004_Nature_428_493
PubMedSearch : Gibbs_2004_Nature_428_493
PubMedID: 15057822
Gene_locus related to this paper: rat-abhea , rat-abheb , rat-cd029 , rat-d3zaw4 , rat-dpp9 , rat-d3zhq1 , rat-d3zkp8 , rat-d3zuq1 , rat-d3zxw8 , rat-d4a4w4 , rat-d4a7w1 , rat-d4a9l7 , rat-d4a071 , rat-d4aa31 , rat-d4aa33 , rat-d4aa61 , rat-dglb , rat-f1lz91 , rat-Kansl3 , rat-nceh1 , rat-Tex30 , ratno-1hlip , ratno-1neur , ratno-1plip , ratno-2neur , ratno-3neur , ratno-3plip , ratno-ABH15 , ratno-ACHE , ratno-balip , ratno-BCHE , ratno-cauxin , ratno-Ces1d , ratno-Ces1e , ratno-Ces2f , ratno-d3ze31 , ratno-d3zp14 , ratno-d3zxi3 , ratno-d3zxq0 , ratno-d3zxq1 , ratno-d4a3d4 , ratno-d4aa05 , ratno-dpp4 , ratno-dpp6 , ratno-est8 , ratno-FAP , ratno-hyep , ratno-hyes , ratno-kmcxe , ratno-lmcxe , ratno-LOC246252 , ratno-MGLL , ratno-pbcxe , ratno-phebest , ratno-Ppgb , ratno-q4qr68 , ratno-q6ayr2 , ratno-q6q629 , ratno-SPG21 , ratno-thyro , rat-m0rc77 , rat-a0a0g2k9y7 , rat-a0a0g2kb83 , rat-d3zba8 , rat-d3zbj1 , rat-d3zcr8 , rat-d3zxw5 , rat-d4a340 , rat-f1lvg7 , rat-m0r509 , rat-m0r5d4 , rat-b5den3 , rat-d3zxk4 , rat-d4a1b6 , rat-d3zmg4 , rat-ab17c

Title : Effects of acute nicotine on hemodynamics and binding of [11C]raclopride to dopamine D2,3 receptors in pig brain - Cumming_2003_Neuroimage_19_1127
Author(s) : Cumming P , Rosa-Neto P , Watanabe H , Smith D , Bender D , Clarke PB , Gjedde A
Ref : Neuroimage , 19 :1127 , 2003
Abstract : Positive reinforcing properties of nicotine and the psychostimulants have been attributed to elevated dopamine release in the basal ganglia. It is well known that the specific binding of [(11)C]raclopride to dopamine D(2,3) receptors in living striatum is reduced by cocaine and amphetamines, revealing increased competition between endogenous dopamine and [(11)C]raclopride for dopamine D(2,3) receptors. However, the sensitivity of [(11)C]raclopride binding to nicotine-induced dopamine release is less well documented. In order to provide the basis for mapping effects of nicotine, we first optimized reference tissue methods for quantifying [(11)C]raclopride binding sites in striatum of living pigs (n = 16). In the same animals, the rate of cerebral blood flow (CBF) was mapped using [(15)O]water. Neither a low dose of nicotine (50 mu kg(-1), iv) nor a high dose of nicotine (500 microg kg(-1), iv) altered CBF in the pig brain, an important condition for calculating the binding of radioligands when using a reference tissue to estimate the free ligand concentration. The methods of Logan and of Lammertsma were compared using the cerebellum or the occipital cortex as reference tissues for calculating the binding potential (pB) of [(11)C]raclolpride in brain. Irrespective of the method used, the mean undrugged baseline pB in striatum (ca. 2.0) was significantly asymmetric, with highest binding in the left caudate and right putamen. Test-retest estimates of pB were stable. Subtraction of Logan pB maps revealed that the low dose of nicotine reduced the pB of [(11)C]raclopride by 10% in a cluster of voxels in the left anteroventral striatum, but this effect did not persist after correction for multiple comparisons. The high dose of nicotine (n = 9) acutely reduced pB by 10% bilaterally in the ventral striatum; 3 h after the high nicotine dose, the reductions had shifted dorsally and caudally into the caudate and putamen. Evidently, nicotine challenge enhances the competition between endogenous dopamine for [(11)C]raclopride binding sites with a complex temporal and spacial pattern in pig brain, initially presenting in the left ventral striatum.
ESTHER : Cumming_2003_Neuroimage_19_1127
PubMedSearch : Cumming_2003_Neuroimage_19_1127
PubMedID: 12880838

Title : The expression of voltage-dependent calcium channel beta subunits in human cerebellum - Volsen_1997_Neurosci_80_161
Author(s) : Volsen SG , Day NC , McCormack AL , Smith W , Craig PJ , Beattie RE , Smith D , Ince PG , Shaw PJ , Ellis SB , Mayne N , Burnett JP , Gillespie A , Harpold MM
Ref : Neuroscience , 80 :161 , 1997
Abstract : The beta subunits of voltage-dependent calcium channels, exert marked regulatory effects on the biophysical and pharmacological properties of this diverse group of ion channels. However, little is known about the comparative neuronal expression of the four classes of beta genes in the CNS. In the current investigation we have closely mapped the distribution of beta1, beta2, beta3 and beta4 subunits in the human cerebellum by both in situ messenger RNA hybridization and protein immunohistochemistry. To our knowledge, these studies represent the first experiments in any species in which the detailed localization of each beta protein has been comparatively mapped in a neuroanatomically-based investigation. The data indicate that all four classes of beta subunits are found in the cerebellum and suggest that in certain neuronal populations they may each be expressed within the same cell. Novel immunohistochemical results further exemplify that the beta voltage-dependent calcium channel subunits are regionally distributed in a highly specific manner and studies of Purkinje cells indicate that this may occur at the subcellular level. Preliminary indication of the subunit composition of certain native voltage-dependent calcium channels is suggested by the observation that the distribution of the beta3 subunit in the cerebellar cortex is identical to that of alpha(1E). Our cumulative data are consistent with the emerging view that different native alpha1/beta subunit associations occur in the CNS.
ESTHER : Volsen_1997_Neurosci_80_161
PubMedSearch : Volsen_1997_Neurosci_80_161
PubMedID: 9252229

Title : Metabolism of rifabutin in human enterocyte and liver microsomes: kinetic parameters, identification of enzyme systems, and drug interactions with macrolides and antifungal agents - Iatsimirskaia_1997_Clin.Pharmacol.Ther_61_554
Author(s) : Iatsimirskaia E , Tulebaev S , Storozhuk E , Utkin I , Smith D , Gerber N , Koudriakova T
Ref : Clinical Pharmacology & Therapeutics , 61 :554 , 1997
Abstract : Biotransformation of rifabutin, an antibiotic used for treatment of tuberculosis in patients infected with the human immunodeficiency virus (HIV), and its interactions with some macrolide and antifungal agents were studied in human intestinal and liver microsomes. Both liver and enterocyte microsomes metabolized rifabutin to 25-O-deacetylrifabutin, 27-O-demethylrifabutin, and 20-, 31-, and 32-hydroxyrifabutin. The same products (except 25-O-deacetylrifabutin) were formed by microsomes from lymphoblastoid cells that contained expressed CYP3A4. The apparent Michaelis-Menten constant (Km); approximately 10 to 12 mumol/L) and maximal velocity (Vmax; approximately 100 pmol/min/mg of protein) values for CYP-mediated metabolism were similar in liver and enterocyte microsomes. Deacetylation of rifabutin (Km approximately 16 to 20 mumol/L and Vmax approximately 50 to 100 pmol/min/mg of protein) was catalyzed by microsomal cholinesterase. Clarithromycin, ketoconazole, and fluconazole inhibited CYP-mediated metabolism of rifabutin in enterocyte microsomes equally or more potently than in liver microsomes but had no effect on cholinesterase activity. Azithromycin did not inhibit in vitro metabolism of rifabutin. This study provides evidence that CYP3A4 and cholinesterase are major enzymes that biotransform rifabutin in humans and that intestinal CYP3A4 contributes significantly to rifabutin presystemic first-pass metabolism and drug interactions with macrolide and antifungal agents.
ESTHER : Iatsimirskaia_1997_Clin.Pharmacol.Ther_61_554
PubMedSearch : Iatsimirskaia_1997_Clin.Pharmacol.Ther_61_554
PubMedID: 9164417