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2.
J Int AIDS Soc ; 24(9): e25801, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34496152

RESUMO

INTRODUCTION: Provider-collected swabs are an unappealing procedure for many transgender women and may have led to suboptimal rates of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) testing. Self-collection for CT/NG testing is recommended for men who have sex with men. However, the information on acceptability and clinical performance to support a recommendation for transgender women is lacking. We aimed to determine the acceptability and satisfaction towards self-collection for CT/NG testing among Thai transgender women. METHODS: Thai transgender women who attended Tangerine Clinic (a transgender-led, integrated, gender-affirming care and sexual health services clinic in Bangkok, Thailand) between May and July 2020 and had condomless sexual intercourse within the past six months were offered to collect urine and perform self-swabs of pharyngeal, rectal, and if applicable, neovaginal compartments for pooled nucleic acid amplification testing for CT/NG infections. Participants received a diagram, video and oral instructions about how to perform self-collection procedure. Those who accepted self-collection were also offered to receive provider collection to evaluate the performance between the two methods. Self-administered questionnaires were used to assess satisfaction. RESULTS: Among 216 transgender women enrolled, 142 (65.7%) accepted self-collection. All who accepted had pharyngeal, rectal and urine samples collected. Of 31 transgender women who had undergone genital surgery, 28 (90.3%) accepted neovaginal self-swab. The acceptance rate increased from 46.2% in May to 84.5% in July 2020. One participant had an invalid result. All transgender women who accepted self-collection could perform it without assistance, and 82.8% were highly satisfied with the method. None reported dissatisfaction. Due to the COVID-19 pandemic, provider collection services were discontinued early, and only eight transgender women were able to perform both methods for performance evaluation. The performance agreement was 100%. CONCLUSIONS: Thai transgender women had high acceptability and satisfaction towards self-collection for CT/NG testing. The performance was promising compared to provider collection. Our results support the implementation of self-collection to the sexually transmitted infection services, particularly during the COVID-19 pandemic where physical distancing is the new normal. A larger study is warranted to determine the performance of self-collection for CT/NG testing in each anatomical compartment and confirm the performance between self-collection and provider collection.


Assuntos
Infecções por Chlamydia/diagnóstico , Chlamydia trachomatis/isolamento & purificação , Gonorreia/diagnóstico , Neisseria gonorrhoeae/isolamento & purificação , Aceitação pelo Paciente de Cuidados de Saúde , Satisfação Pessoal , Manejo de Espécimes/métodos , Pessoas Transgênero , Adulto , COVID-19 , Infecções por Chlamydia/epidemiologia , Feminino , Gonorreia/epidemiologia , Humanos , Masculino , Pandemias , SARS-CoV-2 , Autocuidado , Tailândia/epidemiologia
3.
PLoS One ; 16(8): e0256094, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34398926

RESUMO

BACKGROUND: Suboptimal uptake of HIV testing remains a primary bottleneck to HIV prevention and treatment for men who have sex with men (MSM) and transgender women (TGW) in Thailand. The World Health Organization has recommended HIV self-testing (HIVST) as an additional strategic HIV service. However, HIVST has not been fully endorsed and implemented in many countries in Southeast Asia. The aim of this study was to assess the uptake of oral fluid-based HIVST in MSM and TGW populations in Thailand. METHODS: During 2017 and 2018, we conducted a cross-sectional study using convenience sampling to enroll 2,524 participants from three major urban areas. Participants were recruited during outreach and online activities and were offered unassisted or assisted HIVST, or referral to HIV testing services. A descriptive analysis was performed for summarizing data. RESULTS: A total of 2,502 participants (1,422 MSM and 1,082 TGW) were included in the analysis with about one-third (36.1%) of them being first-time testers. Among all participants enrolled in the study, a total of 2,486 participants (99.3%) selected HIVST versus referral to HIV testing services. Of those who selected HIVST, 2,095 (84.3%) opted for assisted HIVST while the rest opted for unassisted HIVST: 1,148 of 1,411 MSM (81.4%) and 947 of 1,075 TGW (88.1%) selected assisted HIVST. While no serious adverse events were reported during the study, we found that among 179 participants who needed a confirmatory test and were referred to HIV testing services, 108 (60.3.4%) accessed these later services. CONCLUSIONS: This study demonstrated a high uptake of oral fluid-based HIVST among MSM and TGW populations in Thailand and that HIVST could be scaled up through the national epidemic control program. However, a better understanding of HIV testing-seeking behavior and innovative follow-up solutions are needed to improve and monitor linkages to services for people who undertake HIVST.


Assuntos
Infecções por HIV/diagnóstico , Teste de HIV/métodos , HIV/isolamento & purificação , Homossexualidade Masculina/estatística & dados numéricos , Saliva/virologia , Pessoas Transgênero/estatística & dados numéricos , Adolescente , Adulto , Estudos Transversais , Testes Diagnósticos de Rotina/métodos , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Infecções por HIV/virologia , Humanos , Masculino , Autoteste , Parceiros Sexuais/classificação , Tailândia/epidemiologia , Adulto Jovem
4.
J Med Chem ; 64(7): 3813-3826, 2021 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-33724834

RESUMO

Src homology 2 domain-containing inositol phosphate phosphatase 2 (SHIP2) is one of the 10 human inositol phosphate 5-phosphatases. One of its physiological functions is dephosphorylation of phosphatidylinositol 3,4,5-trisphosphate, PtdIns(3,4,5)P3. It is therefore a therapeutic target for pathophysiologies dependent on PtdIns(3,4,5)P3 and PtdIns(3,4)P2. Therapeutic interventions are limited by the dearth of crystallographic data describing ligand/inhibitor binding. An active site-directed fluorescent probe facilitated screening of compound libraries for SHIP2 ligands. With two additional orthogonal assays, several ligands including galloflavin were identified as low micromolar Ki inhibitors. One ligand, an oxo-linked ethylene-bridged dimer of benzene 1,2,4-trisphosphate, was shown to be an uncompetitive inhibitor that binds to a regulatory site on the catalytic domain. We posit that binding of ligands to this site restrains L4 loop motions that are key to interdomain communications that accompany high catalytic activity with phosphoinositide substrate. This site may, therefore, be a future druggable target for medicinal chemistry.


Assuntos
Fluoresceínas/metabolismo , Corantes Fluorescentes/metabolismo , Fosfatos de Inositol/metabolismo , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/antagonistas & inibidores , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/metabolismo , Sítio Alostérico , Sequência de Aminoácidos , Animais , Domínio Catalítico , Linhagem Celular Tumoral , Cristalografia por Raios X , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Humanos , Ligantes , Camundongos , Simulação de Acoplamento Molecular , Células NIH 3T3 , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/química , Ligação Proteica
5.
Sex Health ; 18(1): 21-30, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33632379

RESUMO

Men who have sex with men (MSM) in Western urban areas have seen substantive decreases in new diagnoses of HIV infection. This paper explores whether such declines are present among MSM and transgender women (TGW) in Southeast Asia and discusses implications for HIV policies and programming. A scoping review was conducted of scientific publications and selected documents regarding the spread of HIV infection among MSM and TGW in major urban centres of the Association of Southeast Asian Nations (ASEAN) region. Continued high HIV prevalence and incidence among MSM are found in integrated behavioural and biological surveillance (IBBS) and research studies. HIV prevalence among MSM under IBBS decreased only in Bangkok from 28.6% in 2014 to 10.3% in 2018, whereas it was increasing in Kuala Lumpur, Ho Chi Minh City, Vientiane, and Phnom Penh. HIV/AIDS case reports regarding new HIV infection diagnoses among MSM have started to decrease in Singapore since 2011 and have been plateauing in Metropolitan Manila since 2017. Where data were available, it was found that HIV prevalence among TGW was high and if IBBS was conducted, it was increasing. HIV prevalence among TGW under IBBS in Jakarta had risen to 34.0% (2015) and 14.0% (2019) in Phnom Penh. These findings suggest that most ASEAN member states have so far failed to effectively implement and scale-up scientifically proven biomedical HIV prevention measures and counter stigma and discrimination that impedes access to appropriate HIV prevention and treatment services for MSM and TGW.


Assuntos
Infecções por HIV , Minorias Sexuais e de Gênero , Pessoas Transgênero , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Humanos , Masculino , Programas de Rastreamento , Filipinas , Políticas , Prevalência , Tailândia
6.
ACS Omega ; 5(44): 28793-28811, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33195933

RESUMO

d-myo-Inositol 1,4,5-trisphosphate receptors (IP3Rs) are Ca2+ channels activated by the intracellular messenger inositol 1,4,5-trisphosphate (IP3, 1). The glyconucleotide adenophostin A (AdA, 2) is a potent agonist of IP3Rs. A recent synthesis of d-chiro-inositol adenophostin (InsAdA, 5) employed suitably protected chiral building blocks and replaced the d-glucose core by d-chiro-inositol. An alternative approach to fully chiral material is now reported using intrinsic sugar chirality to avoid early isomer resolution, involving the coupling of a protected and activated racemic myo-inositol derivative to a d-ribose derivative. Diastereoisomer separation was achieved after trans-isopropylidene group removal and the absolute ribose-inositol conjugate stereochemistry assigned with reference to the earlier synthesis. Optimization of stannylene-mediated regiospecific benzylation was explored using the model 1,2-O-isopropylidene-3,6-di-O-benzyl-myo-inositol and conditions successfully transferred to one conjugate diastereoisomer with 3:1 selectivity. However, only roughly 1:1 regiospecificity was achieved on the required diastereoisomer. The conjugate regioisomers of benzyl derivatives 39 and 40 were successfully separated and 39 was transformed subsequently to InsAdA after amination, pan-phosphorylation, and deprotection. InsAdA from this synthetic route bound with greater affinity than AdA to IP3R1 and was more potent in releasing Ca2+ from intracellular stores through IP3Rs. It is the most potent full agonist of IP3R1 known and .equipotent with material from the fully chiral synthetic route.

7.
Sci Rep ; 10(1): 19089, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33154445

RESUMO

Exaggerated transforming growth factor-beta 1 (TGFß1) expression worsens fibroproliferation following bleomycin-induced lung injury in alcohol-fed mice. MicroRNA (miR)-1946a is predicted to bind to the TGFß1 3' untranslated region (UTR), thereby inhibiting its transcription. We hypothesize that alcohol suppresses miR-1946a and induces TGFß1. Primary murine lung fibroblasts (PLFs) were cultured ± alcohol, miR-1946a mimic or inhibitor, and TGFß1 signaling inhibitors. miR-1946a was analyzed after alcohol treatment in vitro and in vivo. TGFß1 expression and TGFß1 3'UTR-luciferase activity was quantified. We showed that alcohol suppressed miR-1946a in the alcohol-fed mouse lungs and PLFs. MiR-1946a inhibitor increased TGFß1 expression in the fibroblast. MiR-1946a mimic treatment suppressed TGFß1 gene expression and TGFß1 3'UTR activity. Overexpression of miR1946a inhibited alcohol-induced TGFß1 gene and protein expression as well as alcohol-induced TGFß1 and α-smooth muscle actin (SMA) protein expression in PLFs. In conclusion, miR-1946a modulates TGFß1 expression through direct interaction with TGFß1 3'UTR. These findings identify a novel mechanism by which alcohol induces TGFß1 in the lung.


Assuntos
Etanol/toxicidade , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Fator de Crescimento Transformador beta1/biossíntese , Fator de Crescimento Transformador beta1/genética , Regiões 3' não Traduzidas , Actinas/genética , Actinas/metabolismo , Alcoolismo/genética , Alcoolismo/metabolismo , Alcoolismo/patologia , Animais , Células Cultivadas , Regulação para Baixo/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Pulmão/patologia , Lesão Pulmonar/induzido quimicamente , Lesão Pulmonar/genética , Lesão Pulmonar/metabolismo , Camundongos , Camundongos Endogâmicos C57BL
8.
J Med Chem ; 63(6): 3238-3251, 2020 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-32052631

RESUMO

Analogues of the Ca2+-releasing intracellular messenger d-myo-inositol 1,4,5-trisphosphate [1, Ins(1,4,5)P3] are important synthetic targets. Replacement of the α-glucopyranosyl motif in the natural product mimic adenophostin 2 by d-chiro-inositol in d-chiro-inositol adenophostin 4 increased the potency. Similar modification of the non-nucleotide Ins(1,4,5)P3 mimic ribophostin 6 may increase the activity. d-chiro-Inositol ribophostin 10 was synthesized by coupling as building blocks suitably protected ribose 12 with l-(+)-3-O-trifluoromethylsulfonyl-6-O-p-methoxybenzyl-1,2:4,5-di-O-isopropylidene-myo-inositol 11. Separable diastereoisomeric 3-O-camphanate esters of (±)-6-O-p-methoxy-benzyl-1,2:4,5-di-O-isopropylidene-myo-inositol allowed the preparation of 11. Selective trans-isopropylidene deprotection in coupled 13, then monobenzylation gave separable regioisomers 15 and 16. p-Methoxybenzyl group deprotection of 16, phosphitylation/oxidation, then deprotection afforded 10, which was a full agonist in Ca2+-release assays; its potency and binding affinity for Ins(1,4,5)P3R were similar to those of adenophostin. Both 4 and 10 elicited a store-operated Ca2+ current ICRAC in patch-clamped cells, unlike Ins(1,4,5)P3 consistent with resistance to metabolism. d-chiro-Inositol ribophostin is the most potent small-molecule Ins(1,4,5)P3 receptor agonist without a nucleobase yet synthesized.


Assuntos
Receptores de Inositol 1,4,5-Trifosfato/agonistas , Fosfatos de Inositol/farmacologia , Ribosemonofosfatos/farmacologia , Animais , Cálcio/metabolismo , Linhagem Celular , Galinhas , Humanos , Fosfatos de Inositol/síntese química , Estrutura Molecular , Ratos , Ribosemonofosfatos/síntese química , Relação Estrutura-Atividade
9.
J Int AIDS Soc ; 22(12): e25430, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31855324

RESUMO

INTRODUCTION: Low uptake of HIV testing and services, including pre-exposure prophylaxis (PrEP), in Thai men who have sex with men (MSM) and transgender women (TGW) may be due to the inaccuracy in self-risk assessment. This study investigated the discordance between self-perceived HIV risk and actual risk. METHODS: Data were obtained between May 2015 and October 2016 from MSM and TGW enrolled in key population-led Test and Treat study in six community health centres in Thailand. Eligible participants were at least 18 years old, Thai national, had sex with men, had unprotected sex with a man in the past six months or had at least three male sex partners in the past six months, and were not known to be HIV positive. Baseline demographic behavioural characteristics questionnaires, including self-perceived HIV risk, were self-administered. Participants received HIV/STI (syphilis/gonorrhoea/chlamydia) testing at baseline. Participants who self-perceived to have low risk, but engaged in HIV-susceptible practices were categorized as having risk discordance (RD). Regression was conducted to assess factors associated with RD among MSM and TGW separately. RESULTS: Of the 882 MSM and 406 TGW participants who perceived themselves as having low HIV risk, over 80% reported at least one of the following: tested HIV positive, engaged in condomless sex, tested positive for a sexually transmitted infection sexually transmitted infection (STI; or used amphetamine-type stimulants. Logistic regression found that living with a male partner (p = 0.005), having never tested for HIV (p = 0.045), and living in Bangkok (p = 0.01) and Chiang Mai (p < 0.001) were associated with increased risk discordance among MSM. Living with a male partner (p = 0.002), being less than 17 years old at sexual debut (p = 0.001), and having a low knowledge score about HIV transmission (p < 0.001) were associated with increased risk discordance among TGW. However, for TGW, being a sex worker decreased the chance of risk discordance (p = 0.034). CONCLUSIONS: Future HIV prevention messages need to fill in the gap between self-perceived risk and actual risk in order to help HIV-vulnerable populations understand their risk better and proactively seek HIV prevention services.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/prevenção & controle , Homossexualidade Masculina/estatística & dados numéricos , Pessoas Transgênero/estatística & dados numéricos , Adolescente , Adulto , Fármacos Anti-HIV/administração & dosagem , Estudos Transversais , Feminino , Humanos , Masculino , Programas de Rastreamento , Profilaxia Pré-Exposição , Prevalência , Profissionais do Sexo , Comportamento Sexual/estatística & dados numéricos , Parceiros Sexuais , Tailândia , Sexo sem Proteção , Adulto Jovem
10.
J Int AIDS Soc ; 22(7): e25338, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31298497

RESUMO

INTRODUCTION: Concerns over potential drug-drug interactions (DDI) between feminizing hormone therapy (FHT) and pre-exposure prophylaxis (PrEP) have hampered uptake and adherence of PrEP among transgender women (TGW). To determine DDI between FHT and PrEP, we measured the pharmacokinetic (PK) parameters of blood plasma estradiol (E2) and tenofovir (TFV) in Thai TGW. METHODS: Twenty TGW who never underwent orchiectomy and had not received injectable FHT within six months were enrolled between January and March 2018. FHT (E2 valerate and cyproterone acetate) were prescribed to participants at baseline until week 5, and then from week 8 until the end of study. Daily PrEP (tenofovir disoproxil fumarate/emtricitabine) was initiated at week 3 and continued without interruption. Intensive E2 PK parameters and testosterone concentration at 24 hours (C24 ) were measured at weeks 3 (without PrEP) and 5 (with PrEP), and intensive TFV PK parameters were measured at weeks 5 (with FHT) and 8 (without FHT). RESULTS: Median (interquartile range) age, body mass index, and creatinine clearance were 21.5 (21-26) years, 20.6 (19.0-22.4) kg/m2 , and 116 (101-126.5) mL/min, respectively. The geometric mean (%CV) of area under curve from time zero to 24 hours (AUC0-24 ), maximum concentration (Cmax ), and C24 of E2 at weeks 3 and 5 were 775.13 (26.2) pg h/mL, 51.47 (26.9) pg/mL, and 15.15 (42.0) pg/mL; and 782.84 (39.6), 55.76 (32.9), and 14.32 (67.4), respectively. The geometric mean (%CV) of TFV AUC0-24 , Cmax , and C24 at weeks 5 and 8 were 2242.1 (26.5) ng h/mL, 353.9 (34.0) ng/mL, and 40.9 (31.4) ng/mL; and 2530.2 (31.3), 311.4 (30.0), and 49.8 (29.6), respectively. The geometric mean of TFV AUC0-24 and C24 at week 5 were significantly less than that at week 8 by 12% (p = 0.03) and 18% (p < 0.001), respectively. There were no significant changes in E2 PK parameters and median C24 of bioavailable testosterone between week 3 and week 5. CONCLUSIONS: Our study demonstrated lower blood plasma TFV exposure in the presence of FHT, suggesting that FHT may potentially affect PrEP efficacy among TGW; but E2 exposure was not affected by PrEP. Further studies are warranted to determine whether these reductions in TFV are clinically significant. Clinical Trial Number: NCT03620734.


Assuntos
Estradiol/uso terapêutico , Infecções por HIV/prevenção & controle , Profilaxia Pré-Exposição , Tenofovir/uso terapêutico , Pessoas Transgênero , Adulto , Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/uso terapêutico , Interações Medicamentosas , Estradiol/administração & dosagem , Estradiol/sangue , Estradiol/farmacocinética , Feminino , Infecções por HIV/tratamento farmacológico , HIV-1 , Humanos , Masculino , Tenofovir/administração & dosagem , Tenofovir/sangue , Tenofovir/farmacocinética , Tailândia
11.
Chem Sci ; 10(20): 5382-5390, 2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-31171961

RESUMO

Reactions that form sec-sec ethers are well known, but few lead to compounds with dense functionality around the O-linkage. Replacement of the α-glucopyranosyl unit of adenophostin A, a potent d-myo-inositol 1,4,5-trisphosphate (IP3R) agonist, with a d-chiro-inositol surrogate acting substantially as a pseudosugar, leads to "d-chiro-inositol adenophostin". At its core, this cyclitol-nucleoside trisphosphate comprises a nucleoside sugar linked via an axial d-chiro-inositol 1-hydroxyl-adenosine 3'-ribose ether linkage. A divergent synthesis of d-chiro-inositol adenophostin has been achieved. Key features of the synthetic strategy to produce a triol for phosphorylation include a new selective mono-tosylation of racemic 1,2:4,5-di-O-isopropylidene-myo-inositol using tosyl imidazole; subsequent conversion of the product into separable camphanate ester derivatives, one leading to a chiral myo-inositol triflate used as a synthetic building block and the other to l-5-O-methyl-myo-inositol [l-(+)-bornesitol] to assign the absolute configuration; the nucleophilic coupling of an alkoxide of a ribose pent-4-ene orthoester unit with a structurally rigid chiral myo-inositol triflate derivative, representing the first sec-sec ether formation between a cyclitol and ribose. Reaction of the coupled product with a silylated nucleobase completes the assembly of the core structure. Further protecting group manipulation, mixed O- and N-phosphorylation, and subsequent removal of all protecting groups in a single step achieves the final product, avoiding a separate N6 protection/deprotection strategy. d-chiro-Inositol adenophostin evoked Ca2+ release through IP3Rs at lower concentrations than adenophostin A, hitherto the most potent known agonist of IP3Rs.

12.
Alcohol Clin Exp Res ; 43(7): 1427-1438, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31081931

RESUMO

BACKGROUND: Alcohol exposure induces TGFß1 and renders the lung susceptible to injury and disrepair. We determined that TGFß1 regulates myofibroblast differentiation through the loss of Thy-1 expression and consequent induction of α-SMA. TGFß1 is important for T helper 17 (Th17) differentiation and IL-17 secretion, which in turn participates in tissue repair. We hypothesized that alcohol induces Th17 differentiation via TGFß1 and that IL-17 produced by these cells contributes to the development of profibrotic lung myofibroblasts. METHODS: Primary lung fibroblasts (PLFs) were treated with alcohol, TGFß1, and IL-17 and then analyzed for Thy-1 expression and cell morphology. Naïve and Th17-polarized CD4+ T cells were exposed to alcohol and assessed for IL-17 expression. CD4+ T cells from alcohol-fed mice were analyzed for Th17 and IL-17 expression. Lungs of control-fed, bleomycin-treated and alcohol-fed, bleomycin-treated mice were analyzed for IL-17 protein expression. RESULTS: Alcohol-treated PLFs expressed lower levels of Thy-1 than untreated cells. TGFß1 or IL-17 exposure suppressed PLF Thy-1 expression. When administered together, TGFß1 and IL-17 additively down-regulated Thy-1 expression. Exposure of naïve and Th17-polarized CD4+ T cells to alcohol induced the Th17 phenotype and augmented their production of IL-17. CD4+ Th17+ levels are elevated in the peripheral compartment but not in the lungs of alcohol-fed animals. Treatment of the PLFs with IL-17 and alcohol induced α-SMA expression. Induction of α-SMA and myofibroblast morphology by IL-17 occurred selectively in a Thy-1- fibroblast subpopulation. Chronic alcohol ingestion augmented lung-specific IL-17 expression following bleomycin-induced lung injury. CONCLUSIONS: Alcohol exposure skews T cells toward a Th17 immune response that in turn primes the lung for fibroproliferative disrepair through loss of Thy-1 expression and induction of myofibroblast differentiation. These effects suggest that IL-17 and TGFß1 contribute to fibroproliferative disrepair in the lung and targeting these proteins could limit morbidity and mortality following lung injury in alcoholic individuals.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Depressores do Sistema Nervoso Central/farmacologia , Etanol/farmacologia , Fibroblastos/efeitos dos fármacos , Interleucina-17/biossíntese , Pulmão/patologia , Miofibroblastos/efeitos dos fármacos , Antígenos Thy-1/biossíntese , Antígenos Thy-1/genética , Actinas/biossíntese , Actinas/genética , Animais , Contagem de Linfócito CD4 , Transdiferenciação Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Linfotoxina-alfa/biossíntese , Camundongos , Camundongos Endogâmicos C57BL , Linfócitos T/efeitos dos fármacos
13.
Biochemistry ; 55(9): 1384-97, 2016 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-26854536

RESUMO

The inositol polyphosphate 5-phosphatase INPP5B hydrolyzes the 5-phosphate group from water- and lipid-soluble signaling messengers. Two synthetic benzene and biphenyl polyphosphates (BzP/BiPhPs), simplified surrogates of inositol phosphates and phospholipid headgroups, were identified by thermodynamic studies as potent INPP5B ligands. The X-ray structure of the complex between INPP5B and biphenyl 3,3',4,4',5,5'-hexakisphosphate [BiPh(3,3',4,4',5,5')P6, IC50 5.5 µM] was determined at 2.89 Å resolution. One inhibitor pole locates in the phospholipid headgroup binding site and the second solvent-exposed ring binds to the His-Tag of another INPP5B molecule, while a molecule of inorganic phosphate is also present in the active site. Benzene 1,2,3-trisphosphate [Bz(1,2,3)P3] [one ring of BiPh(3,3',4,4',5,5')P6] inhibits INPP5B ca. 6-fold less potently. Co-crystallization with benzene 1,2,4,5-tetrakisphosphate [Bz(1,2,4,5)P4, IC50 = 6.3 µM] yielded a structure refined at 2.9 Å resolution. Conserved residues among the 5-phosphatase family mediate interactions with Bz(1,2,4,5)P4 and BiPh(3,3',4,4',5,5')P6 similar to those with the polar groups present in positions 1, 4, 5, and 6 on the inositol ring of the substrate. 5-Phosphatase specificity most likely resides in the variable zone located close to the 2- and 3-positions of the inositol ring, offering insights to inhibitor design. We propose that the inorganic phosphate present in the INPP5B-BiPh(3,3',4,4',5,5')P6 complex mimics the postcleavage substrate 5-phosphate released by INPP5B in the catalytic site, allowing elucidation of two new key features in the catalytic mechanism proposed for the family of phosphoinositide 5-phosphatases: first, the involvement of the conserved Arg-451 in the interaction with the 5-phosphate and second, identification of the water molecule that initiates 5-phosphate hydrolysis. Our model also has implications for the proposed "moving metal" mechanism.


Assuntos
Fosfatos de Inositol/química , Fosfatos de Inositol/metabolismo , Monoéster Fosfórico Hidrolases/química , Monoéster Fosfórico Hidrolases/metabolismo , Sítios de Ligação/fisiologia , Cristalografia por Raios X , Estrutura Secundária de Proteína
14.
Harm Reduct J ; 12: 39, 2015 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-26471235

RESUMO

BACKGROUND: As a dual response to the HIV epidemic and the high level of injecting drug use in Vietnam, the Ministry of Health (MOH) initiated a pilot methadone maintenance therapy (MMT) program in Hai Phong and Ho Chi Minh City (HCMC) in early 2009. The objectives of the pilot were to provide evidence on whether MMT could be successfully implemented in Vietnam and scaled up to other localities. METHODS: A prospective study was conducted among 965 opiate drug users admitted to the pilot. Data on demographic characteristics, sexual behaviors, substance use behaviors (including heroin use), and blood-borne virus infection (HIV, hepatitis B, and hepatitis C) were collected at treatment initiation and then again at 3-, 6-, 9-, 12-, 18-, and 24-month intervals thereafter. RESULTS: Twenty-four months after treatment initiation, heroin use as measured by urine test or self-report had reduced from 100 % of participants at both sites to 14.6 % in Hai Phong and 22.9 % in HCMC. When adjusted for multiple factors in Generalized Estimating Equations (GEE) logistic regression modeling, independent predictors of continued heroin use after 24 months of MMT in HCMC were the following: poor methadone adherence (adjusted odds ratio (AOR) = 3.7, 95 % confidence interval (CI) 1.8-7.8); currently on antiretroviral treatment (ART) (AOR = 1.8, 95 % CI 1.4-2.4); currently on TB treatment (AOR = 2.2, 95 % CI 1.4-3.4); currently experiencing family conflict (AOR = 1.6, 95 % CI 1.1-2.4); and currently employed (AOR = 0.8, 95 % CI 0.6-1.0). For Hai Phong participants, predictors were the following: currently on ART (AOR = 2.0, 95 % CI = 1.4-3.0); currently experiencing family conflict (AOR = 2.0, 95 % CI = 1.0-3.9); and moderate adherence to methadone (AOR = 2.1, 95 % CI = 1.2-1.9). In Hai Phong, the percentage of participants who were employed had also increased by end of study from 35.0 to 52.8 %, while in HCMC the level remained relatively unchanged, between 52.2 and 55.1 %. DISCUSSION: Study findings were used in multiple fora to convince policymakers and the public on the significant and vital role MMT can play in reducing heroin use and improving quality of life for individuals and families. Four years after this study was completed, Vietnam had expanded MMT to 162 clinics in 44 provinces serving 32,000 patients.


Assuntos
Dependência de Heroína/reabilitação , Metadona/uso terapêutico , Tratamento de Substituição de Opiáceos/estatística & dados numéricos , Abuso de Substâncias por Via Intravenosa/reabilitação , Adulto , Estudos de Coortes , Feminino , Seguimentos , Infecções por HIV/prevenção & controle , Humanos , Masculino , Entorpecentes/uso terapêutico , Projetos Piloto , Estudos Prospectivos , Qualidade de Vida , Vietnã , Adulto Jovem
15.
Am J Physiol Cell Physiol ; 309(9): C616-26, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26333597

RESUMO

Idiopathic pulmonary fibrosis is a progressive lung disease that increases in incidence with age. We identified a profibrotic lung phenotype in aging mice characterized by an increase in the number of fibroblasts lacking the expression of thymocyte differentiation antigen 1 (Thy-1) and an increase in transforming growth factor (TGF)-ß1 expression. It has been shown that Thy-1 expression can be epigenetically modified. Lung fibroblasts (PLFs) were treated with TGF-ß1 ± DNA methyltransferase (DNMT) inhibitor 5-aza-2'-deoxycytidine (5-AZA) and analyzed for Thy-1 gene and protein expression, DNMT protein expression, and activity. α-Smooth muscle actin (α-SMA) and collagen type 1 (Col1A1) gene and protein expression was assessed. PLFs were transfected with DNMT1 silencing RNA ± TGF-ß1. TGF-ß1 inhibited Thy-1 gene and protein expression in PLFs, and cotreatment with 5-AZA ameliorated this effect and appeared to inhibit DNMT1 activation. TGF-ß1 induced Thy-1 promoter methylation as assessed by quantitative methyl PCR. Treatment with 5-AZA attenuated TGF-ß1-induced Col1A1 gene and protein expression and α-SMA gene expression (but not α-SMA protein expression). Inhibiting DNMT1 with silencing RNA attenuated TGF-ß1-induced DNMT activity and its downstream suppression of Thy-1 mRNA and protein expression as well as inhibited α-SMA mRNA and Col1A1 mRNA and protein expression, and showed a decreased trend in Thy-1 promoter methylation. Immunofluorescence for α-SMA suggested that 5-AZA inhibited stress fiber formation. These findings suggest that TGF-ß1 epigenetically regulates lung fibroblast phenotype through methylation of the Thy-1 promoter. Targeted inhibition of DNMT in the right clinical context might prevent fibroblast to myofibroblast transdifferentiation and collagen deposition, which in turn could prevent fibrogenesis in the lung and other organs.


Assuntos
Metilação de DNA/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fibrose Pulmonar Idiopática/genética , Pulmão/efeitos dos fármacos , Antígenos Thy-1/genética , Fator de Crescimento Transformador beta1/farmacologia , Actinas/genética , Actinas/metabolismo , Animais , Sequência de Bases , Transdiferenciação Celular , Células Cultivadas , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Cadeia alfa 1 do Colágeno Tipo I , DNA (Citosina-5-)-Metiltransferase 1 , DNA (Citosina-5-)-Metiltransferases/antagonistas & inibidores , DNA (Citosina-5-)-Metiltransferases/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , Inibidores Enzimáticos/farmacologia , Fibroblastos/metabolismo , Fibroblastos/patologia , Fibrose Pulmonar Idiopática/metabolismo , Fibrose Pulmonar Idiopática/patologia , Pulmão/metabolismo , Pulmão/patologia , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Fenótipo , Regiões Promotoras Genéticas , Interferência de RNA , Antígenos Thy-1/metabolismo , Transfecção
16.
Biochem Soc Trans ; 43(3): 417-25, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26009185

RESUMO

Synthetic compounds open up new avenues to interrogate and manipulate intracellular Ca2+ signalling pathways. They may ultimately lead to drug-like analogues to intervene in disease. Recent advances in chemical biology tools available to probe Ca2+ signalling are described, with a particular focus on those synthetic analogues from our group that have enhanced biological understanding or represent a step towards more drug-like molecules. Adenophostin (AdA) is the most potent known agonist at the inositol 1,4,5-trisphosphate receptor (IP3R) and synthetic analogues provide a binding model for receptor activation and channel opening. 2-O-Modified inositol 1,4,5-trisphosphate (IP3) derivatives that are partial agonists at the IP3R reveal key conformational changes of the receptor upon ligand binding. Biphenyl polyphosphates illustrate that simple non-inositol surrogates can be engineered to give prototype IP3R agonists or antagonists and act as templates for protein co-crystallization. Cyclic adenosine 5'-diphosphoribose (cADPR) can be selectively modified using total synthesis, generating chemically and biologically stable tools to investigate Ca2+ release via the ryanodine receptor (RyR) and to interfere with cADPR synthesis and degradation. The first neutral analogues with a synthetic pyrophosphate bioisostere surprisingly retain the ability to release Ca2+, suggesting a new route to membrane-permeant tools. Adenosine 5'-diphosphoribose (ADPR) activates the Ca2+-, Na+- and K+-permeable transient receptor potential melastatin 2 (TRPM2) cation channel. Synthetic ADPR analogues provide the first structure-activity relationship (SAR) for this emerging messenger and the first functional antagonists. An analogue based on the nicotinic acid motif of nicotinic acid adenine dinucleotide phosphate (NAADP) antagonizes NAADP-mediated Ca2+ release in vitro and is effective in vivo against induced heart arrhythmia and autoimmune disease, illustrating the therapeutic potential of targeted small molecules.


Assuntos
Adenosina Difosfato Ribose/química , Arritmias Cardíacas/tratamento farmacológico , Sinalização do Cálcio/efeitos dos fármacos , Cálcio/metabolismo , Bibliotecas de Moléculas Pequenas/uso terapêutico , Adenosina/análogos & derivados , Adenosina/química , Adenosina/uso terapêutico , Adenosina Difosfato Ribose/análogos & derivados , Adenosina Difosfato Ribose/síntese química , Arritmias Cardíacas/patologia , Bloqueadores dos Canais de Cálcio/uso terapêutico , Humanos , Inositol 1,4,5-Trifosfato/genética , Inositol 1,4,5-Trifosfato/metabolismo , Receptores de Inositol 1,4,5-Trifosfato/antagonistas & inibidores , NADP/análogos & derivados , NADP/antagonistas & inibidores , Canal de Liberação de Cálcio do Receptor de Rianodina/efeitos dos fármacos , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Bibliotecas de Moléculas Pequenas/síntese química , Bibliotecas de Moléculas Pequenas/química , Relação Estrutura-Atividade
17.
Alcohol Clin Exp Res ; 38(11): 2731-42, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25421510

RESUMO

BACKGROUND: Chronic alcohol ingestion induces the expression of transforming growth factor beta-1(TGFß1), inhibits nuclear factor (erythroid-derived 2)-like 2 (Nrf2)-mediated activation of the antioxidant response element (ARE), depletes alveolar glutathione pools, and potentiates acute lung injury. In this study, we examined the mechanistic relationship between TGFß1 and Nrf2-ARE signaling in the experimental alcoholic lung. METHODS: Wild-type mice were treated ± alcohol in drinking water for 8 weeks and their lungs were assessed for Nrf2 expression. In parallel, mouse lung fibroblasts were cultured ± alcohol and treated ± sulforaphane (SFP; an activator of Nrf2), ±TGFß1, ±TGFß1 neutralizing antibody, and/or ±activin receptor-like kinase 5 inhibitors (to block TGß1 receptor signaling) and then analyzed for the expression of Nrf2, Kelch-like ECH-associated protein 1 (Keap1) and TGFß1, Nrf2-ARE activity, and the expression of the Nrf2-ARE-dependent antioxidants glutathione s-transferase theta 2 (GSTT2) and glutamate-cysteine ligase catalytic subunit (GCLC). Finally, silencing RNA (siRNA) of Nrf2 was then performed prior to alcohol exposure and subsequent analysis of TGFß1 expression. RESULTS: Alcohol treatment in vivo or in vitro decreased Nrf2 expression in murine whole lung and lung fibroblasts, respectively. In parallel, alcohol exposure in vitro decreased Keap1 gene and protein expression in lung fibroblasts. Furthermore, alcohol exposure increased TGFß1 expression but decreased Nrf2-ARE activity and expression of the ARE-dependent genes for GSTT2 and GCLC. These effects of alcohol were prevented by treatment with SFP; in contrast, Nrf2 SiRNA expression exacerbated alcohol-induced TGFß1 expression. Finally, TGFß1 treatment directly suppressed Nrf2-ARE activity whereas blocking TGFß1 signaling attenuated alcohol-induced suppression of Nrf2-ARE activity. CONCLUSIONS: Alcohol-induced oxidative stress is mediated by TGFß1, which suppresses Nrf2-ARE-dependent expression of antioxidant defenses and creates a vicious cycle that feeds back to further increase TGFß1 expression. These effects of alcohol can be mitigated by activation of Nrf2, suggesting a potential therapy in individuals at risk for lung injury due to alcohol abuse.


Assuntos
Etanol/toxicidade , Fibroblastos/metabolismo , Pulmão/metabolismo , Fator 2 Relacionado a NF-E2/biossíntese , Fator de Crescimento Transformador beta1/fisiologia , Animais , Linhagem Celular Transformada , Fibroblastos/efeitos dos fármacos , Humanos , Pulmão/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Células NIH 3T3 , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Fator de Crescimento Transformador beta1/farmacologia
18.
Alcohol Clin Exp Res ; 38(2): 336-43, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24033682

RESUMO

BACKGROUND: Alcohol abuse increases the risk for acute lung injury (ALI). In both experimental models and in clinical studies, chronic alcohol ingestion causes airway oxidative stress and glutathione depletion and increases the expression of transforming growth factor beta-1 (TGFß1), a potent inducer of fibrosis, in the lung. Therefore, we hypothesized that alcohol ingestion could promote aberrant fibrosis following experimental ALI and that treatment with the glutathione precursor s-adenosylmethionine (SAMe) could mitigate these effects. METHODS: Three-month-old C57BL/6 mice were fed standard chow ± alcohol (20% v/v) in their drinking water for 8 weeks and ±SAMe (4% w/v) during the last 4 weeks. ALI was induced by intratracheal instillation of bleomycin (2.5 units/kg), and lungs were assessed histologically at 7 and 14 days for fibrosis and at 14 days for the expression of extracellular matrix proteins and TGFß1. RESULTS: Alcohol ingestion had no apparent effect on lung inflammation at 7 days, but at 14 days after bleomycin treatment, it increased lung tissue collagen deposition, hydroxyproline content, and the release of activated TGFß1 into the airway. In contrast, SAMe supplementation completely mitigated alcohol-induced priming of these aberrant fibrotic changes through decreased TGFß1 expression in the lung. In parallel, SAMe decreased alcohol-induced TGFß1 and Smad3 mRNA expressions by lung fibroblasts in vitro. CONCLUSIONS: These new experimental findings demonstrate that chronic alcohol ingestion renders the experimental mouse lung susceptible to fibrosis following bleomycin-induced ALI, and that these effects are likely driven by alcohol-mediated oxidative stress and its induction and activation of TGFß1.


Assuntos
Antibióticos Antineoplásicos/toxicidade , Bleomicina/toxicidade , Depressores do Sistema Nervoso Central/toxicidade , Etanol/toxicidade , Fibrose Pulmonar/induzido quimicamente , Actinas/biossíntese , Animais , Antibióticos Antineoplásicos/antagonistas & inibidores , Bleomicina/antagonistas & inibidores , Diferenciação Celular/efeitos dos fármacos , Depressores do Sistema Nervoso Central/antagonistas & inibidores , Dieta , Ensaio de Imunoadsorção Enzimática , Etanol/antagonistas & inibidores , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Hidroxiprolina/metabolismo , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Miofibroblastos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Pneumonia/patologia , Fibrose Pulmonar/patologia , Fibrose Pulmonar/prevenção & controle , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , S-Adenosilmetionina/farmacologia , Fator de Crescimento Transformador beta1/biossíntese
19.
ACS Chem Biol ; 7(5): 822-8, 2012 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-22330088

RESUMO

Phosphoinositides regulate many cellular processes, and cellular levels are controlled by kinases and phosphatases. SHIP2 (SH2 (Src homology 2)-domain-containing inositol-phosphatase-2) plays a critical role in phosphoinositide signaling, cleaving the 5-phosphate from phosphatidylinositol 3,4,5-trisphosphate. SHIP2 is thought to be involved in type-2 diabetes and obesity, conditions that could therefore be open to pharmacological modulation of the enzyme. However, rational design of SHIP2 inhibitors has been limited by the absence of a high-resolution structure. Here, we present a 2.1 Å resolution crystal structure of the phosphatase domain of SHIP2 bound to the synthetic ligand biphenyl 2,3',4,5',6-pentakisphosphate (BiPh(2,3',4,5',6)P(5)). BiPh(2,3',4,5',6)P(5) is not a SHIP2 substrate but inhibits Ins(1,3,4,5)P(4) hydrolysis with an IC(50) of 24.8 ± 3.0 µM, (K(m) for Ins(1,3,4,5)P(4) is 215 ± 28 µM). Molecular dynamics simulations suggest that when BiPh(2,3',4,5',6)P(5) binds to SHIP2, a flexible loop folds over and encloses the ligand. Compounds targeting such a closed conformation might therefore deliver SHIP2-specific drugs.


Assuntos
Compostos de Bifenilo/química , Compostos de Bifenilo/farmacologia , Desenho de Fármacos , Fosfatos/química , Fosfatos/farmacologia , Fosfatos de Fosfatidilinositol/química , Monoéster Fosfórico Hidrolases/antagonistas & inibidores , Monoéster Fosfórico Hidrolases/química , Cristalografia por Raios X , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Humanos , Modelos Moleculares , Fosfatos de Fosfatidilinositol/farmacologia , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases , Monoéster Fosfórico Hidrolases/metabolismo , Domínios de Homologia de src
20.
Messenger (Los Angel) ; 1(2): 160-166, 2012 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24749013

RESUMO

A potential extracellular target for inositol phosphates and analogues with anticancer properties is identified. Proteins from detergent-solubilised HeLa cell lysates bound to a novel affinity column of myo-inositol 1,3,4,5,6-pentakisphosphate (InsP5) coupled to Affigel-10. One high-affinity ligand was fibrinogen Bß. Inositol phosphates and analogues were able to elute purified fibrinogen from this matrix. InsP5 and the inositol phosphate mimic biphenyl 2,3',4,5',6-pentakisphosphate (BiPhP5) bind fibrinogen in vitro, and block the effects of fibrinogen in A549 cell-based assays of proliferation and migration. They are also able to prevent the fibrinogen-mediated activation of phosphatidylinositol 3-kinase. These effects of fibrinogen appear to be mediated through the intercellular adhesion molecule-1 (ICAM-1), as cells not expressing ICAM-1 fail to respond. In contrast, myo-inositol hexakisphosphate and the epimeric scyllo-inositol 1,2,3,4,5-pentakisphosphate were without effect. These findings are consistent with earlier reports that higher inositol phosphates have anticancer properties. This new mechanism of action and target for these extracellular inositol phosphates to have their effects allows a re-evaluation of earlier data.

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