Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 29
Filtrar
1.
PLoS Pathog ; 17(1): e1009214, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33465157

RESUMO

The precise role of CD4 T cell turnover in maintaining HIV persistence during antiretroviral therapy (ART) has not yet been well characterized. In resting CD4 T cell subpopulations from 24 HIV-infected ART-suppressed and 6 HIV-uninfected individuals, we directly measured cellular turnover by heavy water labeling, HIV reservoir size by integrated HIV-DNA (intDNA) and cell-associated HIV-RNA (caRNA), and HIV reservoir clonality by proviral integration site sequencing. Compared to HIV-negatives, ART-suppressed individuals had similar fractional replacement rates in all subpopulations, but lower absolute proliferation rates of all subpopulations other than effector memory (TEM) cells, and lower plasma IL-7 levels (p = 0.0004). Median CD4 T cell half-lives decreased with cell differentiation from naïve to TEM cells (3 years to 3 months, p<0.001). TEM had the fastest replacement rates, were most highly enriched for intDNA and caRNA, and contained the most clonal proviral expansion. Clonal proviruses detected in less mature subpopulations were more expanded in TEM, suggesting that they were maintained through cell differentiation. Earlier ART initiation was associated with lower levels of intDNA, caRNA and fractional replacement rates. In conclusion, circulating integrated HIV proviruses appear to be maintained both by slow turnover of immature CD4 subpopulations, and by clonal expansion as well as cell differentiation into effector cells with faster replacement rates.


Assuntos
Antirretrovirais/uso terapêutico , Linfócitos T CD4-Positivos/patologia , Diferenciação Celular , Infecções por HIV/virologia , HIV-1/imunologia , Carga Viral , Replicação Viral , Adulto , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/virologia , Estudos de Casos e Controles , DNA Viral/análise , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Infecções por HIV/patologia , HIV-1/efeitos dos fármacos , HIV-1/genética , Humanos , Masculino , Pessoa de Meia-Idade
2.
Proc Natl Acad Sci U S A ; 117(27): 15763-15771, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32571938

RESUMO

HIV-1 latency is a major barrier to cure. Identification of small molecules that destabilize latency and allow immune clearance of infected cells could lead to treatment-free remission. In vitro models of HIV-1 latency involving cell lines or primary cells have been developed for characterization of HIV-1 latency and high-throughput screening for latency-reversing agents (LRAs). We have shown that the majority of LRAs identified to date are relatively ineffective in cells from infected individuals despite activity in model systems. We show here that, for diverse LRAs, latency reversal observed in model systems involves a heat shock factor 1 (HSF1)-mediated stress pathway. Small-molecule inhibition of HSF1 attenuated HIV-1 latency reversal by histone deactylase inhibitors, protein kinase C agonists, and proteasome inhibitors without interfering with the known mechanism of action of these LRAs. However, latency reversal by second mitochondria-derived activator of caspase (SMAC) mimetics was not affected by inhibition of HSF1. In cells from infected individuals, inhibition of HSF1 attenuated latency reversal by phorbol ester+ionomycin but not by anti-CD3+anti-CD28. HSF1 promotes elongation of HIV-1 RNA by recruiting P-TEFb to the HIV-1 long terminal repeat (LTR), and we show that inhibition of HSF1 attenuates the formation of elongated HIV-1 transcripts. We demonstrate that in vitro models of latency have higher levels of the P-TEFb subunit cyclin T1 than primary cells, which may explain why many LRAs are functional in model systems but relatively ineffective in primary cells. Together, these studies provide insights into why particular LRA combinations are effective in reversing latency in cells from infected individuals.


Assuntos
Infecções por HIV/genética , HIV-1/genética , Fatores de Transcrição de Choque Térmico/genética , Latência Viral/genética , Fármacos Anti-HIV/farmacologia , Proteínas Reguladoras de Apoptose/genética , Ciclina T/genética , Infecções por HIV/virologia , HIV-1/patogenicidade , Fatores de Transcrição de Choque Térmico/antagonistas & inibidores , Inibidores de Histona Desacetilases/farmacologia , Humanos , Proteínas Mitocondriais/genética , Fator B de Elongação Transcricional Positiva/genética , Proteína Quinase C/genética , RNA Viral/efeitos dos fármacos , RNA Viral/genética , Bibliotecas de Moléculas Pequenas/farmacologia , Sequências Repetidas Terminais/genética , Ativação Viral/genética
3.
PLoS Pathog ; 14(11): e1007357, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30440043

RESUMO

Latently-infected CD4+ T cells are widely considered to be the major barrier to a cure for HIV. Much of our understanding of HIV latency comes from latency models and blood cells, but most HIV-infected cells reside in lymphoid tissues such as the gut. We hypothesized that tissue-specific environments may impact the mechanisms that govern HIV expression. To assess the degree to which different mechanisms inhibit HIV transcription in the gut and blood, we quantified HIV transcripts suggestive of transcriptional interference (U3-U5; "Read-through"), initiation (TAR), 5' elongation (R-U5-pre-Gag; "Long LTR"), distal transcription (Nef), completion (U3-polyA; "PolyA"), and multiple splicing (Tat-Rev) in matched peripheral blood mononuclear cells (PBMCs) and rectal biopsies, and matched FACS-sorted CD4+ T cells from blood and rectum, from two cohorts of ART-suppressed individuals. Like the PBMCs, rectal biopsies showed low levels of read-through transcripts (median = 23 copies/106 cells) and a gradient of total (679)>elongated(75)>Nef(16)>polyadenylated (11)>multiply-spliced HIV RNAs(<1) [p<0.05 for all], demonstrating blocks to HIV transcriptional elongation, completion, and splicing. Rectal CD4+ T cells showed a similar gradient of total>polyadenylated>multiply-spliced transcripts, but the ratio of total to elongated transcripts was 6-fold lower than in blood CD4+ T cells (P = 0.016), suggesting less of a block to HIV transcriptional elongation in rectal CD4+ T cells. Levels of total transcripts per provirus were significantly lower in rectal biopsies compared to PBMCs (median 3.5 vs. 15.4; P = 0.008) and in sorted CD4+ T cells from rectum compared to blood (median 2.7 vs. 31.8; P = 0.016). The lower levels of HIV transcriptional initiation and of most HIV transcripts per provirus in the rectum suggest that this site may be enriched for latently-infected cells, cells in which latency is maintained by different mechanisms, or cells in a "deeper" state of latency. These are important considerations for designing therapies that aim to disrupt HIV latency in all tissue compartments.


Assuntos
Infecções por HIV/metabolismo , HIV-1/fisiologia , Latência Viral/fisiologia , Adulto , Linfócitos T CD4-Positivos/virologia , Regulação Viral da Expressão Gênica/genética , Infecções por HIV/fisiopatologia , Infecções por HIV/virologia , HIV-1/genética , Humanos , Tecido Linfoide/virologia , Masculino , Pessoa de Meia-Idade , RNA Viral/metabolismo , Reto/virologia , Transcrição Gênica/fisiologia , Transcriptoma/genética
4.
Retrovirology ; 16(1): 32, 2019 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-31711503

RESUMO

BACKGROUND: HIV-infected cell lines are widely used to study latent HIV infection, which is considered the main barrier to HIV cure. We hypothesized that these cell lines differ from each other and from cells from HIV-infected individuals in the mechanisms underlying latency. RESULTS: To quantify the degree to which HIV expression is inhibited by blocks at different stages of HIV transcription, we employed a recently-described panel of RT-ddPCR assays to measure levels of 7 HIV transcripts ("read-through," initiated, 5' elongated, mid-transcribed/unspliced [Pol], distal-transcribed [Nef], polyadenylated, and multiply-sliced [Tat-Rev]) in bulk populations of latently-infected (U1, ACH-2, J-Lat) and productively-infected (8E5, activated J-Lat) cell lines. To assess single-cell variation and investigate cellular genes associated with HIV transcriptional blocks, we developed a novel multiplex qPCR panel and quantified single cell levels of 7 HIV targets and 89 cellular transcripts in latently- and productively-infected cell lines. The bulk cell HIV transcription profile differed dramatically between cell lines and cells from ART-suppressed individuals. Compared to cells from ART-suppressed individuals, latent cell lines showed lower levels of HIV transcriptional initiation and higher levels of polyadenylation and splicing. ACH-2 and J-Lat cells showed different forms of transcriptional interference, while U1 cells showed a block to elongation. Single-cell studies revealed marked variation between/within cell lines in expression of HIV transcripts, T cell phenotypic markers, antiviral factors, and genes implicated in latency. Expression of multiply-spliced HIV Tat-Rev was associated with expression of cellular genes involved in activation, tissue retention, T cell transcription, and apoptosis/survival. CONCLUSIONS: HIV-infected cell lines differ from each other and from cells from ART-treated individuals in the mechanisms governing latent HIV infection. These differences in viral and cellular gene expression must be considered when gauging the suitability of a given cell line for future research on HIV. At the same time, some features were shared across cell lines, such as low expression of antiviral defense genes and a relationship between productive infection and genes involved in survival. These features may contribute to HIV latency or persistence in vivo, and deserve further study using novel single cell assays such as those described in this manuscript.


Assuntos
HIV-1/genética , HIV-1/fisiologia , Transcriptoma , Ativação Viral/genética , Latência Viral/genética , Linhagem Celular , DNA Viral/análise , Regulação Viral da Expressão Gênica , Interações entre Hospedeiro e Microrganismos/genética , Humanos , Células Jurkat , Reação em Cadeia da Polimerase Multiplex , RNA Viral/genética , Transcrição Gênica , Células U937
5.
J Med Syst ; 41(4): 64, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28283998

RESUMO

Self-directed learning is associated with knowledge and performance improvements, increased identification and amelioration of knowledge gaps, and heightened critical appraisal of available evidence. We developed and implemented a decision support system that could support self-directed learning for anesthesia residents by soliciting resident input in case selection. We hypothesized that residents would utilize this system to request complex cases, and that more advanced residents would request more complex cases. Prospective, observational study involving 101 anesthesiology residents. We used a web-based interface, RHINOS [Residents Helping in Navigating Operating Room (OR) Scheduling], which allowed residents to share their rank-ordered preferences for OR assignment. Number of cases per OR, anesthesia base units, time units, and proportion of inpatient cases were used as proxies for case complexity. Data were analyzed using a mixed linear model. Residents requested rooms with fewer cases [F(3,22,350) = 194.0; p < 0.001], more base units [F(3,19,158) = 291.4; p < 0.001], more time units [F(3,19,744) = 186.4; p < 0.001], and a greater proportion of cases requiring inpatient preoperative evaluation [F(3,51,929) = 11.3; p < 0.001]. In most cases, these differences were greater for more advanced residents. As hypothesized, residents requested ORs with higher case complexity, and these cases more often required inpatient preoperative evaluation. More advanced residents exhibited a stronger preference for more educational cases than junior residents.


Assuntos
Anestesiologia/educação , Internato e Residência , Salas Cirúrgicas , Humanos , Estudos Prospectivos
6.
Curr Opin Anaesthesiol ; 30(5): 570-576, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28708674

RESUMO

PURPOSE OF REVIEW: Chemotherapy-induced peripheral neuropathy (CIPN) is a common, frequently chronic condition characterized by pain and decreased function. Given the growing number of cancer survivors and an increasing recognition of opioid therapy limitations, there is a need for critical analysis of the literature in directing an informed and thoughtful approach for the management of painful CIPN. RECENT FINDINGS: A PubMed search for 'chemotherapy-induced peripheral neuropathy AND pain' identifies 259 publications between 1 January 2016 and 31 March 2017. Based on review of this literature, we aim to present a clinically relevant update of painful CIPN. Notably, the use of duloxetine as a first-line agent in treatment of CIPN is confirmed. Moreover, clinical trials focus on nonpharmacologic strategies for managing painful CIPN. SUMMARY: Despite the volume of recent publications, there are limited preventive or therapeutic strategies for CIPN supported by high-level evidence. Duloxetine remains the only pharmacologic agent with demonstrated benefit; its clinical use should be routinely considered. Moving forward, nonopioid analgesic therapies will likely play an increasing role in CIPN treatment, but further research is necessary to confirm their utility. Promising therapies include vitamin B12 supplementation, physical therapy, and various forms of neuromodulation.


Assuntos
Doenças do Sistema Nervoso Periférico/induzido quimicamente , Cloridrato de Duloxetina/uso terapêutico , Humanos , Doenças do Sistema Nervoso Periférico/diagnóstico , Doenças do Sistema Nervoso Periférico/prevenção & controle , Doenças do Sistema Nervoso Periférico/terapia , Vitamina B 12/administração & dosagem
8.
Exp Dermatol ; 23(9): 645-51, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24980072

RESUMO

Systemic and topical glucocorticoids (GC) can cause significant adverse effects not only on the dermis, but also on epidermal structure and function. In epidermis, a striking GC-induced alteration in permeability barrier function occurs that can be attributed to an inhibition of epidermal mitogenesis, differentiation and lipid production. As prior studies in normal hairless mice demonstrated that topical applications of a flavonoid ingredient found in citrus, hesperidin, improve epidermal barrier function by stimulating epidermal proliferation and differentiation, we assessed here whether its topical applications could prevent GC-induced changes in epidermal function in murine skin and the basis for such effects. When hairless mice were co-treated topically with GC and 2% hesperidin twice-daily for 9 days, hesperidin co-applications prevented the expected GC-induced impairments of epidermal permeability barrier homoeostasis and stratum corneum (SC) acidification. These preventive effects could be attributed to a significant increase in filaggrin expression, enhanced epidermal ß-glucocerebrosidase activity and accelerated lamellar bilayer maturation, the last two likely attributable to a hesperidin-induced reduction in stratum corneum pH. Furthermore, co-applications of hesperidin with GC largely prevented the expected GC-induced inhibition of epidermal proliferation. Finally, topical hesperidin increased epidermal glutathione reductase mRNA expression, which could counteract multiple functional negative effects of GC on epidermis. Together, these results show that topical hesperidin prevents GC-induced epidermal side effects by divergent mechanisms.


Assuntos
Clobetasol/efeitos adversos , Clobetasol/antagonistas & inibidores , Epiderme/efeitos dos fármacos , Glucocorticoides/efeitos adversos , Glucocorticoides/antagonistas & inibidores , Hesperidina/administração & dosagem , Administração Tópica , Animais , Proliferação de Células/efeitos dos fármacos , Clobetasol/administração & dosagem , Epiderme/patologia , Epiderme/fisiopatologia , Feminino , Proteínas Filagrinas , Glucocorticoides/administração & dosagem , Glutationa Redutase/genética , Proteínas de Filamentos Intermediários/genética , Metabolismo dos Lipídeos/efeitos dos fármacos , Camundongos , Camundongos Pelados , Camundongos Endogâmicos C57BL , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Regulação para Cima/efeitos dos fármacos
9.
AIDS ; 38(9): 1281-1291, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38626436

RESUMO

OBJECTIVES: Some drugs that augment cell-intrinsic defenses or modulate cell death/survival pathways have been reported to selectively kill cells infected with HIV or Simian Immunodeficiency Virus (SIV), but comparative studies are lacking. We hypothesized that these drugs may differ in their ability to kill cells infected with intact and defective proviruses. DESIGN: To investigate this hypothesis, drugs were tested ex vivo on peripheral blood mononuclear cells (PBMC) from nine antiretroviral therapy (ART)-suppressed individuals. METHODS: We tested drugs currently in clinical use or human trials, including auranofin (p53 modulator), interferon alpha2A, interferon gamma, acitretin (RIG-I inducer), GS-9620/vesatolimod (TLR7 agonist), nivolumab (PD-1 blocker), obatoclax (Bcl-2 inhibitor), birinapant [inhibitor of apoptosis proteins (IAP) inhibitor], bortezomib (proteasome inhibitor), and INK128/sapanisertib [mammalian target of rapamycin mTOR] [c]1/2 inhibitor). After 6 days of treatment, we measured cell counts/viabilities and quantified levels of total, intact, and defective HIV DNA by droplet digital PCR (Intact Proviral DNA Assay). RESULTS: Obatoclax reduced intact HIV DNA [median = 27-30% of dimethyl sulfoxide control (DMSO)] but not defective or total HIV DNA. Other drugs showed no statistically significant effects. CONCLUSION: Obatoclax and other Bcl-2 inhibitors deserve further study in combination therapies aimed at reducing the intact HIV reservoir in order to achieve a functional cure and/or reduce HIV-associated immune activation.


Assuntos
Infecções por HIV , Indóis , Leucócitos Mononucleares , Provírus , Pirróis , Humanos , Indóis/farmacologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Pirróis/farmacologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/virologia , Provírus/efeitos dos fármacos
10.
Exp Dermatol ; 22(2): 113-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23362869

RESUMO

Caspase-14 is an enzyme that is expressed predominantly in cornifying epithelia and catalyses the degradation of profilaggrin. Additionally, caspase-14 plays an important role in the terminal differentiation of keratinocytes. However, how caspase-14 expression is regulated remains largely unknown. Here we demonstrate that ceramides (C(2) -Cer and C(6) -Cer), but not other sphingolipids (C(8) -glucosylceramides, sphinganine, sphingosine-1-phosphate or ceramide-1-phosphate), increase caspase-14 expression (mRNA and protein) in cultured human keratinocytes in a dose- and time-dependent manner. Inhibitors of glucosylceramide synthase and ceramidase increase endogenous ceramide levels and also increase caspase-14 expression, indicating an important regulatory role for ceramides and suggesting that the conversion of ceramides to other metabolites is not required. The increase in caspase-14 expression induced by ceramides is first seen at 16 h and requires new protein synthesis, suggesting that the ceramide-induced increase is likely an indirect effect. Furthermore, ceramides increase caspase-14 gene expression primarily by increasing transcription. Blocking de novo synthesis of ceramides does not affect caspase-14 expression, suggesting that basal expression is not dependent on ceramide levels. These studies show that ceramides, an important structural lipid, stimulate caspase-14 expression providing a mechanism for coordinately regulating the formation of lipid lamellar membranes with the formation of corneocytes.


Assuntos
Caspases/metabolismo , Ceramidas/metabolismo , Regulação Enzimológica da Expressão Gênica , Queratinócitos/enzimologia , Células Cultivadas , Inibidores Enzimáticos/farmacologia , Glucosiltransferases/antagonistas & inibidores , Humanos , Lipídeos/química , Receptores X do Fígado , Receptores Nucleares Órfãos/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Regiões Promotoras Genéticas , RNA Mensageiro/metabolismo , Fatores de Tempo , Ativação Transcricional
11.
Exp Dermatol ; 22(3): 210-5, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23489424

RESUMO

The beneficial effects of certain herbal medicines on cutaneous function have been appreciated for centuries. Among these agents, chrysanthemum extract, apigenin, has been used for skin care, particularly in China, for millennia. However, the underlying mechanisms by which apigenin benefits the skin are not known. In this study, we first determined whether topical apigenin positively influences permeability barrier homoeostasis, and then the basis thereof. Hairless mice were treated topically with either 0.1% apigenin or vehicle alone twice daily for 9 days. At the end of the treatments, permeability barrier function was assessed with either an electrolytic water analyzer or a Tewameter. Our results show that topical apigenin significantly enhanced permeability barrier homoeostasis after tape stripping, although basal permeability barrier function remained unchanged. Improved barrier function correlated with enhanced filaggrin expression and lamellar body production, which was paralleled by elevated mRNA levels for the epidermal ABCA12. The mRNA levels for key lipid synthetic enzymes also were upregulated by apigenin. Finally, both cathelicidin-related peptide and mouse beta-defensin 3 immunostaining were increased by apigenin. We conclude that topical apigenin improves epidermal permeability barrier function by stimulating epidermal differentiation, lipid synthesis and secretion, as well as cutaneous antimicrobial peptide production. Apigenin could be useful for the prevention and treatment of skin disorders characterized by permeability barrier dysfunction, associated with reduced filaggrin levels and impaired antimicrobial defenses, such as atopic dermatitis.


Assuntos
Apigenina/administração & dosagem , Apigenina/farmacologia , Permeabilidade da Membrana Celular/efeitos dos fármacos , Epiderme/fisiologia , Homeostase/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacologia , Transportadores de Cassetes de Ligação de ATP/metabolismo , Administração Tópica , Animais , Peptídeos Catiônicos Antimicrobianos/metabolismo , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Permeabilidade da Membrana Celular/fisiologia , Células Cultivadas , Chrysanthemum , Relação Dose-Resposta a Droga , Células Epidérmicas , Epiderme/efeitos dos fármacos , Feminino , Proteínas Filagrinas , Homeostase/fisiologia , Proteínas de Filamentos Intermediários/metabolismo , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Camundongos , Camundongos Pelados , Modelos Animais , Pele/citologia , Pele/efeitos dos fármacos , Pele/metabolismo , beta-Defensinas/metabolismo , Catelicidinas
13.
medRxiv ; 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37333215

RESUMO

Individual treatments for chronic low back pain (CLBP) have small magnitude effects. Combining different types of treatments may produce larger effects. This study used a 2×2 factorial randomized controlled trial (RCT) design to combine procedural and behavioral treatments for CLBP. The study aims were to: (1) assess feasibility of conducting a factorial RCT of these treatments; and (2) estimate individual and combined treatment effects of (a) lumbar radiofrequency ablation (LRFA) of the dorsal ramus medial branch nerves (vs. a simulated LRFA control procedure) and (b) Activity Tracker-Informed Video-Enabled Cognitive Behavioral Therapy program for CLBP (AcTIVE-CBT) (vs. an educational control treatment) on back-related disability at 3 months post-randomization. Participants (n=13) were randomized in a 1:1:1:1 ratio. Feasibility goals included an enrollment proportion ≥30%, a randomization proportion ≥80%, and a ≥80% proportion of randomized participants completing the 3-month Roland-Morris Disability Questionnaire (RMDQ) primary outcome endpoint. An intent-to-treat analysis was used. The enrollment proportion was 62%, the randomization proportion was 81%, and all randomized participants completed the primary outcome. Though not statistically significant, there was a beneficial, moderate-magnitude effect of LRFA vs. control on 3-month RMDQ (-3.25 RMDQ points; 95% CI: -10.18, 3.67). There was a significant, beneficial, large-magnitude effect of AcTIVECBT vs. control (-6.29, 95% CI: -10.97, -1.60). Though not statistically significant, there was a beneficial, large effect of LRFA+AcTIVE-CBT vs. control (-8.37; 95% CI: -21.47, 4.74). We conclude that it is feasible to conduct an RCT combining procedural and behavioral treatments for CLBP.

14.
Exp Dermatol ; 20(7): 595-9, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21457357

RESUMO

Aquaporin 3 (AQP3), a member of the aquaglyceroporin family, which transports water and glycerol, is robustly expressed in epidermis and plays an important role in stratum corneum hydration, permeability barrier function and wound healing. PPAR and LXR activation regulates the expression of many proteins in the epidermis and thereby can affect epidermal function. Here, we report that PPARgamma activators markedly stimulate AQP3 mRNA expression in both undifferentiated and differentiated cultured human keratinocytes (CHKs). The increase in AQP3 mRNA by PPARgamma activator occurs in a dose- and time-dependent fashion. Increased AQP3 mRNA levels are accompanied by an increase in AQP3 protein in undifferentiated keratinocytes and a significant increase in glycerol uptake. Activation of LXR, RAR and RXR also increases AQP3 mRNA levels in undifferentiated and differentiated CHKs, but to a lesser extent. PPARdelta activation stimulates AQP3 expression in undifferentiated CHKs but decreases expression in differentiated CHKs. In contrast, PPARalpha activators do not alter AQP3 expression. AQP9 and AQP10, other members of aquaglyceroporin family, are less abundantly expressed in CHKs, and their expression levels are not significantly altered by treatment with LXR, PPAR, RAR or RXR activators. Finally, when topically applied, the PPARgamma activator, ciglitazone, induces AQP3 but not AQP9 gene expression in mouse epidermis. Our data demonstrate that PPAR and LXR activators stimulate AQP3 expression, providing an additional mechanism by which PPAR and LXR activators regulate epidermal function.


Assuntos
Aquaporina 3/metabolismo , Epiderme/metabolismo , Regulação da Expressão Gênica/fisiologia , Queratinócitos/metabolismo , PPAR gama/agonistas , Animais , Aquaporina 3/genética , Aquaporinas/genética , Cálcio/farmacologia , Diferenciação Celular/fisiologia , Células Cultivadas , Relação Dose-Resposta a Droga , Epiderme/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Glicerol/metabolismo , Humanos , Queratinócitos/efeitos dos fármacos , Receptores X do Fígado , Camundongos , Camundongos Endogâmicos , Receptores Nucleares Órfãos/agonistas , PPAR alfa/agonistas , PPAR delta/agonistas , PPAR gama/metabolismo , Receptores do Ácido Retinoico/agonistas , Receptores X de Retinoides/agonistas , Tiazolidinedionas/farmacologia
15.
J Int AIDS Soc ; 24(7): e25738, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34235864

RESUMO

INTRODUCTION: Sex-specific differences affect multiple aspects of HIV infection, yet few studies have quantified HIV levels in tissues from women. Since an HIV functional cure will likely require a major reduction of infected cells from most tissues, we measured total and intact HIV DNA and the HIV transcription profile in blood, gut, genital tract and liver from HIV-positive antiretroviral therapy (ART) -treated women. METHODS: Peripheral blood mononuclear cells (PBMC) and biopsies from the gastrointestinal (ileum, colon, rectosigmoid +/- liver) and genital (ectocervix, endocervix and endometrium) tracts were collected from 6 ART-treated (HIV RNA < 200 copies/mL) women. HIV DNA (total and intact) and levels of read-through, initiated (total), 5'elongated, polyadenylated and multiply spliced HIV transcripts were measured by droplet digital PCR. Immunophenotyping of cells was performed using Cytometry by time of flight (CyTOF). RESULTS: We detected total HIV DNA in all tissues and intact HIV DNA in blood, ileum, colon, rectosigmoid and ectocervix. Initiated HIV transcripts per provirus were higher in PBMC and endometrium than in ileum, colon, rectosigmoid, ectocervix or endocervix, and higher in the rectum than either ileum or colon. 5'Elongated HIV transcripts per provirus were comparable in PBMC and endometrium, but higher than in gut or cervical samples. Polyadenylated and multiply spliced HIV transcripts were detected in PBMC (6/6 and 3/6 individuals respectively), but rarely in the tissues. CONCLUSIONS: These results suggest tissue-specific differences in the mechanisms that govern HIV expression, with lower HIV transcription in most tissues than blood. Therapies aimed at disrupting latency, such as latency-reversing or latency-silencing agents, will be required to penetrate into multiple tissues and target different blocks to HIV transcription.


Assuntos
Infecções por HIV , HIV-1 , DNA , Feminino , Genitália , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Humanos , Leucócitos Mononucleares , Fígado , Masculino , RNA Viral
16.
J Lipid Res ; 51(11): 3207-16, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20719759

RESUMO

Phospholipids are required for epidermal lamellar body formation. Glycerol 3-phosphate acyltransferases (GPATs) catalyze the initial step in the biosynthesis of glycerolipids. Little is known about the expression and regulation of GPATs in epidermis/keratinocytes. Here, we demonstrate that GPAT 1, 3, and 4 are expressed in epidermis/keratinocytes, whereas GPAT2 is not detected. In mouse epidermis, GPAT 3 and 4 are mainly localized to the upper layers whereas GPAT1 is found in both the upper and lower layers. GPAT1 and 3 mRNA increase during fetal rat epidermal development. No change in GPAT expression was observed in adult mice following acute permeability barrier disruption. Calcium-induced human keratinocyte differentiation increased GPAT3 mRNA whereas both GPAT1 and 4 mRNA levels decreased. In parallel, total GPAT activity increased 2-fold in differentiated keratinocytes attributable to an increase in N-ethylmaleimide (NEM) sensitive GPAT activity localized to microsomes with little change in NEM resistant activity, consistent with an increase in GPAT3. Furthermore, PPARγ or PPARδ activators increased GPAT3 mRNA, microsomal GPAT activity, and glycerol lipid synthesis without affecting the expression of GPAT1 or 4. Finally, both PPARγ and PPARδ activators increased GPAT3 mRNA via increasing its transcription. Thus, multiple isoforms of GPAT are expressed and differentially regulated in epidermis/keratinocytes.


Assuntos
Epiderme/metabolismo , Regulação Enzimológica da Expressão Gênica , Glicerol-3-Fosfato O-Aciltransferase/genética , Glicerol-3-Fosfato O-Aciltransferase/metabolismo , Queratinócitos/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Epiderme/efeitos dos fármacos , Epiderme/crescimento & desenvolvimento , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Receptores X do Fígado , Camundongos , Receptores Nucleares Órfãos/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Ratos , Tiazolidinedionas/farmacologia , Ativação Transcricional/efeitos dos fármacos
17.
J Lipid Res ; 51(11): 3185-95, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20675829

RESUMO

ABCG1, a member of the ATP binding cassette superfamily, facilitates the efflux of cholesterol from cells to HDL. In this study, we demonstrate that ABCG1 is expressed in cultured human keratinocytes and murine epidermis, and induced during keratinocyte differentiation, with increased levels in the outer epidermis. ABCG1 is regulated by liver X receptor (LXR) and peroxisome proliferator-activated receptor-δ (PPAR-δ) activators, cellular sterol levels, and acute barrier disruption. Both LXR and PPAR-δ activators markedly stimulate ABCG1 expression in a dose- and time-dependent fashion. PPAR-γ activators also increase ABCG1 expression, but to a lesser degree. In contrast, activators of PPAR-α, retinoic acid receptor, retinoid X receptor, and vitamin D receptor do not alter ABCG1 expression. In response to increased intracellular sterol levels, ABCG1 expression increases, whereas inhibition of cholesterol biosynthesis decreases ABCG1 expression. In vivo, ABCG1 is stimulated 3-6 h after acute barrier disruption by either tape stripping or acetone treatment, an increase that can be inhibited by occlusion, suggesting a potential role of ABCG1 in permeability barrier homeostasis. Although Abcg1-null mice display normal epidermal permeability barrier function and gross morphology, abnormal lamellar body (LB) contents and secretion leading to impaired lamellar bilayer formation could be demonstrated by electron microscopy, indicating a potential role of ABCG1 in normal LB formation and secretion.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Epiderme/metabolismo , Regulação da Expressão Gênica , Queratinócitos/metabolismo , Lipoproteínas/genética , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células Epidérmicas , Epiderme/efeitos dos fármacos , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Técnicas de Inativação de Genes , Humanos , Hidrocarbonetos Fluorados/farmacologia , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Lipoproteínas/metabolismo , Receptores X do Fígado , Camundongos , Receptores Nucleares Órfãos/metabolismo , PPAR delta/metabolismo , Permeabilidade/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Esteróis/farmacologia , Sulfonamidas/farmacologia , Regulação para Cima/efeitos dos fármacos
18.
AIDS ; 34(14): 2013-2024, 2020 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-32910065

RESUMO

OBJECTIVE: While latently HIV-infected cells have been described in the blood, it is unclear whether a similar inducible reservoir exists in the gut, where most HIV-infected cells reside. Tissue-specific environments may contribute to differences in the mechanisms that govern latent HIV infection and amenability to reactivation. We sought to determine whether HIV-infected cells from the blood and gut differ in their responses to T-cell activation and mechanistically distinct latency reversing agents (LRAs). DESIGN: Cross sectional study using samples from HIV-infected individuals (n = 11). METHODS: Matched peripheral blood mononuclear cells (PBMC) and dissociated total cells from rectum ±â€Šileum were treated ex vivo for 24 h with anti-CD3/CD28 or LRAs in the presence of antiretrovirals. HIV DNA and 'read-through', initiated, 5' elongated, completed, and multiply-spliced HIV transcripts were quantified using droplet digital PCR. RESULTS: T-cell activation increased levels of all HIV transcripts in PBMC and gut cells, and was the only treatment that increased multiply-spliced HIV RNA. Disulfiram increased initiated HIV transcripts in PBMC but not gut cells, while ingenol mebutate increased HIV transcription more in gut cells. Romidepsin increased HIV transcription in PBMC and gut cells, but the increase in transcription initiation was greater in PBMC. CONCLUSION: The gut harbors HIV-infected cells in a latent-like state that can be reversed by T-cell activation involving CD3/CD28 signaling. Histone deacetylation and protein kinase B may contribute less to HIV transcriptional initiation in the gut, whereas protein kinase C may contribute more. New LRAs or combinations are needed to induce multiply-spliced HIV and should be tested on both blood and gut.


Assuntos
Microbioma Gastrointestinal , Infecções por HIV/sangue , Infecções por HIV/virologia , HIV-1/genética , HIV-1/fisiologia , Latência Viral/fisiologia , Linfócitos T CD4-Positivos , Estudos Transversais , Diterpenos , Infecções por HIV/tratamento farmacológico , Humanos , Leucócitos Mononucleares , Reação em Cadeia da Polimerase , RNA Viral , Ativação Viral/genética
19.
WMJ ; 118(2): 91-94, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31532936

RESUMO

INTRODUCTION: Neuropsychiatric symptoms are a well-described side effect of systemic corticosteroid therapy and can range from mild to severe. CASE PRESENTATION: We describe a case of substance-induced psychosis following epidural injection of 10 mg dexamethasone. Three days after the procedure, the patient developed symptoms including anger, hostility, insomnia, paranoia, and delusions. Symptoms resolved between 7 and 17 days. DISCUSSION: In the past 50 years, there have been several case reports of severe neuropsychiatric effects following intraarticular or other interventional pain injections with various corticosteroids. More recent reviews have identified possible risk factors, including corticosteroid dose, patient age, sex, and history of neuropsychiatric disorder, among others, although these conclusions are not duplicated across all studies. CONCLUSION: Recommendations for practice include patient and family education on possible adverse effects of corticosteroid administration, utilization of minimum effective doses for interventional procedures, and the consideration of close follow-up and multidisciplinary coordination, especially in high-risk patients.


Assuntos
Corticosteroides/efeitos adversos , Injeções Epidurais , Dor Lombar/tratamento farmacológico , Psicoses Induzidas por Substâncias/etiologia , Humanos , Masculino , Pessoa de Meia-Idade
20.
AIDS ; 33(3): 425-431, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30531314

RESUMO

OBJECTIVES: Reversing HIV-1 latency has been suggested as a strategy to eradicate HIV-1. We investigated the effect of romidepsin on the HIV transcription profile in participants from the REDUC part B clinical trial. DESIGN: Seventeen participants on suppressive antiretroviral therapy were vaccinated with six doses of the therapeutic vaccine Vacc-4x followed by treatment with three doses of romidepsin. Samples from nine study participants were available for HIV transcription profile analysis. METHODS: Read-through, total (TAR), elongated (longLTR), polyadenylated (polyA) and multiply-spliced (Tat-Rev) HIV transcripts and total HIV DNA were quantified at baseline (visit 1) and 4 h after the second (visit 10b) and third (visit 11b) romidepsin infusions. RESULTS: Read-through, total, elongated, and polyadenylated HIV transcripts increased after romidepsin infusion (P = 0.020, P = 0.0078, P = 0.0039, P = 0.027, respectively), but no changes were observed in multiply-spliced HIV RNA or HIV DNA. No change was observed in the ratio of read-through/total HIV transcripts. The ratio of elongated/total HIV RNA increased after romidepsin (P = 0.016), whereas the ratio of polyadenylated/elongated HIV decreased. Both elongated HIV transcripts and total HIV DNA correlated negatively with the time to viral rebound after interruption of ART. CONCLUSIONS: In these patients, romidepsin increased early events in HIV transcription (initiation and especially elongation), but had less effect on later stages (completion, multiple splicing) that may be required for comprehensive latency reversal and cell killing. Without cell death, increased HIV transcription before or after latency reversal may hasten viral rebound after therapy interruption.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Depsipeptídeos/administração & dosagem , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Transcrição Gênica/efeitos dos fármacos , Latência Viral/efeitos dos fármacos , Antirretrovirais/uso terapêutico , Seguimentos , Perfilação da Expressão Gênica , Humanos , Resposta Viral Sustentada
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA