RESUMO
Segmentation of the white matter in MRI scans of the rat brain presents a significant challenge due to the low contrast. Existing anatomical reference maps of rat brain are usually constructed from fixed tissue, which may suffer from geometrical distortions due to fixation/processing. To significantly increase the in vivo contrast between white and gray matter in the rat brain we used a known neurotoxicant hexachlorophene, which produces selective white matter damage. This model was used to map white matter in the rat brain and estimate the partial white matter content in any given imaging voxel. Hexachlorophene was administered to rats at a dose of 30 mg/kg orally once a day over five consecutive days. A significant white matter changes were observed using quantitative T2 maps, from which the partial white matter content throughout the whole rat brain was derived. Several assumptions were made: hexachlorophene affects T2 relaxation only in the white matter; T2 of gray matter is relatively uniform in the brain; apparent T2 value in a given voxel is a combination of T2s from white and gray matter portions of that voxel, hexachlorophene affects nearly 100 % of white matter. The partial white matter map of the rat brain was constructed with the resolution of 0.2 × 0.2 × 1.0 mm per voxel. This map could be adjusted for segmentation of the brain tissue with preset threshold of the white matter content, or to establish the tissue composition in any region of interest among other applications.
Assuntos
Substância Branca , Ratos , Animais , Hexaclorofeno , Processamento de Imagem Assistida por Computador/métodos , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Substância Cinzenta , Mapeamento Encefálico/métodosRESUMO
In the aim to determine neurotoxicity, new methods are being validated, including tests and test batteries comprising in vitro and in vivo approaches. Alternative test models such as the zebrafish (Danio rerio) embryo have received increasing attention, with minor modifications of the fish embryo toxicity test (FET; OECD TG 236) as a tool to assess behavioral endpoints related to neurotoxicity during early developmental stages. The spontaneous tail movement assay, also known as coiling assay, assesses the development of random movement into complex behavioral patterns and has proven sensitive to acetylcholine esterase inhibitors at sublethal concentrations. The present study explored the sensitivity of the assay to neurotoxicants with other modes of action (MoAs). Here, five compounds with diverse MoAs were tested at sublethal concentrations: acrylamide, carbaryl, hexachlorophene, ibuprofen, and rotenone. While carbaryl, hexachlorophene, and rotenone consistently induced severe behavioral alterations by ~ 30 h post fertilization (hpf), acrylamide and ibuprofen expressed time- and/or concentration-dependent effects. At 37-38 hpf, additional observations revealed behavioral changes during dark phases with a strict concentration-dependency. The study documented the applicability of the coiling assay to MoA-dependent behavioral alterations at sublethal concentrations, underlining its potential as a component of a neurotoxicity test battery.
Assuntos
Síndromes Neurotóxicas , Poluentes Químicos da Água , Animais , Peixe-Zebra , Rotenona , Carbaril , Hexaclorofeno , Ibuprofeno/toxicidade , Acrilamidas , Embrião não MamíferoRESUMO
3ß-Hydroxysteroid dehydrogenase/steroid Δ5,4-isomerase 1 (3ß-HSD1) plays a critical role in the biosynthesis of progesterone from pregnenolone in the human placenta to maintain normal pregnancy. Whether they inhibit placental 3ß-HSD1 and mode of inhibition remains unclear. In this study, we screened 21 pesticides and fungicides in five classes to inhibit human 3ß-HSD1 and compared them to rat homolog 3ß-HSD4. 3ß-HSD activity was measured by catalyzing pregnenolone to progesterone in the presence of NAD+. Of the 21 chemicals, azoles (difenoconazole), thiocarbamates (thiram and ferbam) and organochlorine (hexachlorophene) significantly inhibited human 3ß-HSD1 with half maximal inhibitory concentration (IC50) values of 2.77, 0.24, 0.68, and 17.96 µM, respectively. We also found that difenoconazole, ferbam and hexachlorophene are mixed/competitive inhibitors of 3ß-HSD1 while thiram is a mixed/noncompetitive inhibitor. Docking analysis showed that difenoconazole and hexachlorophene bound steroid-binding site. Difenoconazole and hexachlorophene except thiram and ferbam also significantly inhibited rat 3ß-HSD4 activity with IC50 of 1.12 and 2.28 µM, respectively. Thiram and ferbam significantly inhibited human 3ß-HSD1 possibly by interfering with cysteine residues, while they had no effects on rat 3ß-HSD4. In conclusion, some pesticides potently inhibit placental 3ß-HSD, leading to the reduction of progesterone formation.
Assuntos
Fungicidas Industriais , Praguicidas , Humanos , Ratos , Feminino , Gravidez , Animais , Placenta/metabolismo , Fungicidas Industriais/toxicidade , Progesterona , 3-Hidroxiesteroide Desidrogenases/metabolismo , Praguicidas/toxicidade , Tiram , Hexaclorofeno , Esteroides , Pregnenolona/metabolismoRESUMO
Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations account for 35% of the genetic alterations in non-small cell lung cancer (NSCLC). The Src-homology region 2-containing protein tyrosine phosphatase 2 (SHP2), encoded by PTPN11, is closely involved in RAS downstream pathways and development of many tumors by affecting cell proliferation, differentiation, and immunity. Targeting SHP2 with small molecules may be a promising avenue for the treatment of KRAS-mutant (mut) NSCLC. Herein, hexachlorophene (HCP) was identified as a SHP2 inhibitor with an IC50 value of 5.63 ± 0.75 µM through screening of the FDA-approved drug library. HCP specifically inhibited SHP2 rather than other phosphatases. Molecular docking showed that HCP displayed an orientation favorable for nucleophilic attack in the catalytic domain of SHP2. HCP suppressed viability of multiple KRAS-mut and KRAS-wild type cells and induced senescence and apoptosis in KRAS-mut cells. Moreover, HCP reversed epithelial-mesenchymal transition to suppress metastasis in KRAS-mut cells, and inhibited the RAS/MEK/ERK and PI3K/AKT signaling pathways by suppression of SHP2 phosphorylation and formation SHP2/Grb2/Gab1/SOS1 complex. In summary, HCP can act as a specific SHP2 inhibitor to inhibit KRAS-mut NSCLC cell proliferation and metastasis and induce senescence through suppression of the RAF/MEK/ERK and PI3K/AKT pathways. HCP warrants further investigation as a new compound skeleton for the development of selective SHP2 inhibitors for the treatment of NSCLC.
Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Hexaclorofeno , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Simulação de Acoplamento Molecular , Mutação , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Transdução de SinaisRESUMO
Leishmaniasis is an infectious disease caused by parasites of the genus Leishmania and transmitted by the bite of a sand fly. To date, most available drugs for treatment are toxic and beyond the economic means of those affected by the disease. Protein disulfide isomerase (PDI) is a chaperone protein that plays a major role in the folding of newly synthesized proteins, specifically assisting in disulfide bond formation, breakage, or rearrangement in all non-native proteins. In previous work, we demonstrated that Leishmania major PDI (LmPDI) has an essential role in pathogen virulence. Furthermore, inhibition of LmPDI further blocked parasite infection in macrophages. In this study, we utilized a computer-aided approach to design a series of LmPDI inhibitors. Fragment-based virtual screening allowed for the understanding of the inhibitors' modes of action on LmPDI active sites. The generated compounds obtained after multiple rounds of virtual screening were synthesized and significantly inhibited target LmPDI reductase activity and were shown to decrease in vitro parasite growth in human monocyte-derived macrophages. This novel cheminformatics and synthetic approach led to the identification of a new series of compounds that might be optimized into novel drugs, likely more specific and less toxic for the treatment of leishmaniasis.
Assuntos
Anti-Infecciosos/síntese química , Inibidores Enzimáticos/química , Hexaclorofeno/síntese química , Leishmania major/enzimologia , Leishmaniose/tratamento farmacológico , Isomerases de Dissulfetos de Proteínas/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/síntese química , Anti-Infecciosos/farmacologia , Domínio Catalítico , Desenho Assistido por Computador , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Hexaclorofeno/farmacologia , Humanos , Simulação de Acoplamento Molecular , Ligação Proteica , Conformação Proteica , Bibliotecas de Moléculas Pequenas/farmacologia , Relação Estrutura-AtividadeRESUMO
It is well established that hexachlorophene, which is used as an antibacterial agent, causes intramyelinic edema in humans and animal models. The hexachlorophene myelinopathy model, in which male Sprague-Dawley rats received 25 to 30 mg/kg hexachlorophene by gavage for up to 5 days, provided an opportunity to compare traditional neuropathology evaluations with magnetic resonance microscopy (MRM) findings. In addition, stereology assessments of 3 neuroanatomical sites were compared to quantitative measurements of similar structures by MRM. There were positive correlations between hematoxylin and eosin and luxol fast blue stains and MRM for identifying intramyelinic edema in the cingulum of corpus callosum, optic chiasm, anterior commissure (aca), lateral olfactory tracts, pyramidal tracts (py), and white matter tracts in the cerebellum. Stereology assessments were focused on the aca, longitudinal fasciculus of the pons, and py and demonstrated differences between control and treated rats, as was observed using MRM. The added value of MRM assessments was the ability to acquire qualitative 3-dimensional (3-D) images and obtain quantitative measurements of intramyelinic edema in 26 neuroanatomical sites in the intact brain. Also, diffusion tensor imaging (fractional anisotropy [FA]) indicated that there were changes in the cytoarchitecture of the white matter as detected by decreases in the FA in the treated compared to the control rats. This study demonstrates creative strategies that are possible using qualitative and quantitative assessments of potential white matter neurotoxicants in nonclinical toxicity studies. Our results lead us to the conclusion that volumetric analysis by MRM and stereology adds significant value to the standard 2-D microscopic evaluations.
Assuntos
Imagem de Tensor de Difusão , Hexaclorofeno , Animais , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino , Microscopia , Ratos , Ratos Sprague-DawleyRESUMO
We investigated the synthesis of N-docosahexaenoylethanolamine (synaptamide) in neuronal cells from unesterified docosahexaenoic acid (DHA) or DHA-lysophosphatidylcholine (DHA-lysoPC), the two major lipid forms that deliver DHA to the brain, in order to understand the formation of this neurotrophic and neuroprotective metabolite of DHA in the brain. Both substrates were taken up in Neuro2A cells and metabolized to N-docosahexaenoylphosphatidylethanolamine (NDoPE) and synaptamide in a time- and concentration-dependent manner, but unesterified DHA was 1.5 to 2.4 times more effective than DHA-lysoPC at equimolar concentrations. The plasmalogen NDoPE (pNDoPE) amounted more than 80% of NDoPE produced from DHA or DHA-lysoPC, with 16-carbon-pNDoPE being the most abundant species. Inhibition of N-acylphosphatidylethanolamine-phospholipase D (NAPE-PLD) by hexachlorophene or bithionol significantly decreased the synaptamide production, indicating that synaptamide synthesis is mediated at least in part via NDoPE hydrolysis. NDoPE formation occurred much more rapidly than synaptamide production, indicating a precursor-product relationship. Although NDoPE is an intermediate for synaptamide biosynthesis, only about 1% of newly synthesized NDoPE was converted to synaptamide, possibly suggesting additional biological function of NDoPE, particularly for pNDoPE, which is the major form of NDoPE produced.
Assuntos
Ácidos Araquidônicos/biossíntese , Ácidos Docosa-Hexaenoicos/metabolismo , Endocanabinoides/biossíntese , Etanolaminas/metabolismo , Lisofosfatidilcolinas/metabolismo , Neurônios/metabolismo , Animais , Ácidos Araquidônicos/antagonistas & inibidores , Ácidos Araquidônicos/isolamento & purificação , Bitionol/farmacologia , Isótopos de Carbono , Linhagem Celular Tumoral , Cromatografia Líquida , Endocanabinoides/antagonistas & inibidores , Endocanabinoides/isolamento & purificação , Etanolaminas/antagonistas & inibidores , Etanolaminas/isolamento & purificação , Hexaclorofeno/farmacologia , Cinética , Camundongos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Plasmalogênios/antagonistas & inibidores , Plasmalogênios/biossíntese , Plasmalogênios/isolamento & purificação , Alcamidas Poli-Insaturadas/antagonistas & inibidores , Alcamidas Poli-Insaturadas/isolamento & purificação , Espectrometria de Massas em TandemRESUMO
Hexachlorophene (HCP) is used in a range of general cleaning and disinfecting products and has received increased attention due to its damaging effect to the central nervous system in animals and its toxicity in humans. The chemical oxidation of HCP by KMnO4 was performed to systematically evaluate the effects of oxidant dose, pH, temperature, typical anions, humic acid (HA), and various matrices on HCP removal. The second-order rate constant for HCP was determined to be 4.83 × 104 M-1 s-1 at pH 7.0 and 25 °C. The presence of HA can inhibit the removal of HCP by KMnO4, while Cl-, NO3-, SO42-, PO43-, and CO32- have negligible effects. Degradation products analysis of the reaction, as well as theoretical calculations of HCP molecule and its phenoxy radical species, indicated that KMnO4 oxidation for HCP included a C-C bridge bond cleavage, hydroxylation, direct oxidation and self-coupling, and cross-coupling reactions. This study revealed that KMnO4 oxidation is an effective technique for eliminating HCP in real water and wastewater.
Assuntos
Hexaclorofeno/química , Poluentes Químicos da Água/química , Substâncias Húmicas/análise , Cinética , Oxidantes , Oxirredução , Águas Residuárias/análise , Água/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodosRESUMO
N-Acyl-phosphatidylethanolamine phospholipase D (NAPE-PLD) (EC 3.1.4.4) catalyzes the final step in the biosynthesis of N-acyl-ethanolamides. Reduced NAPE-PLD expression and activity may contribute to obesity and inflammation, but a lack of effective NAPE-PLD inhibitors has been a major obstacle to elucidating the role of NAPE-PLD and N-acyl-ethanolamide biosynthesis in these processes. The endogenous bile acid lithocholic acid (LCA) inhibits NAPE-PLD activity (with an IC50 of 68 µm), but LCA is also a highly potent ligand for TGR5 (EC50 0.52 µm). Recently, the first selective small-molecule inhibitor of NAPE-PLD, ARN19874, has been reported (having an IC50 of 34 µm). To identify more potent inhibitors of NAPE-PLD, here we used a quenched fluorescent NAPE analog, PED-A1, as a substrate for recombinant mouse Nape-pld to screen a panel of bile acids and a library of experimental compounds (the Spectrum Collection). Muricholic acids and several other bile acids inhibited Nape-pld with potency similar to that of LCA. We identified 14 potent Nape-pld inhibitors in the Spectrum Collection, with the two most potent (IC50 = â¼2 µm) being symmetrically substituted dichlorophenes, i.e. hexachlorophene and bithionol. Structure-activity relationship assays using additional substituted dichlorophenes identified key moieties needed for Nape-pld inhibition. Both hexachlorophene and bithionol exhibited significant selectivity for Nape-pld compared with nontarget lipase activities such as Streptomyces chromofuscus PLD or serum lipase. Both also effectively inhibited NAPE-PLD activity in cultured HEK293 cells. We conclude that symmetrically substituted dichlorophenes potently inhibit NAPE-PLD in cultured cells and have significant selectivity for NAPE-PLD versus other tissue-associated lipases.
Assuntos
Diclorofeno , Inibidores Enzimáticos , Fosfolipase D , Animais , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Bitionol/química , Bitionol/farmacologia , Diclorofeno/química , Diclorofeno/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Células HEK293 , Hexaclorofeno/química , Hexaclorofeno/farmacologia , Humanos , Camundongos , Fosfolipase D/antagonistas & inibidores , Fosfolipase D/química , Fosfolipase D/metabolismo , Quinazolinas/química , Quinazolinas/farmacologia , Streptomyces/enzimologia , Sulfonamidas/química , Sulfonamidas/farmacologiaRESUMO
To assess photoxicity, several in vitro methods using different cellular models have been developed for preclinical testing. Over prediction of the in vivo photosafety hazard has been however appointed. Herein, we describe the implementation and validation of an in vitro methodology for phototoxicity evaluation based on the 3T3 neutral red uptake phototoxicity test using the HaCaT human keratinocyte cell line, and UVA/UVB radiation. Known positive (5-methoxypsoralen, chlorpromazine, and quinine) and negative (acetyl salicylic acid, hexachlorophene, and sodium lauryl sulphate) controls were tested together with a set of chemical currently used in cosmetic/pharmaceutical formulations. Apart from the advantage of using a cell line of human origin, these cells were generally more resistant to the cytotoxic effects of the test substances relative to the 3T3 mouse fibroblasts when exposed to an UVA irradiation dose of 1.7â¯mW/cm2. Therefore, this HaCaT NRU assay provides a more realistic experimental model that overcomes the over/high sensitivity frequently noted with the 3T3 NRU assay and that is more consistent with the human in vivo situation. Using a more representative method can prevent time-consuming and expensive in vivo testing in both animal models and humans that can significantly delay the clinical development of new chemicals.
Assuntos
Alternativas aos Testes com Animais/métodos , Bioensaio/métodos , Dermatite Fototóxica , Queratinócitos/efeitos dos fármacos , Queratinócitos/efeitos da radiação , Testes de Toxicidade/métodos , 5-Metoxipsoraleno/toxicidade , Animais , Aspirina/toxicidade , Linhagem Celular , Clorpromazina/toxicidade , Cosméticos/toxicidade , Hexaclorofeno/toxicidade , Humanos , Camundongos , Vermelho Neutro/metabolismo , Quinina/toxicidade , Dodecilsulfato de Sódio/toxicidade , Raios UltravioletaRESUMO
In a previous study, we showed that 2', 3'-Cyclic Nucleotide 3'-Phosphodiesterase (CNPase) expression is induced in different temporal patterns in the cerebrum, cerebellum and medulla oblongata of hexachlorophene (HCP) and cuprizone (CPZ) treated rats. Here, we additionally examined the histopathological changes and CNPase expression in the spinal cord to clarify the reproducibility of different temporal patterns of CNPase expression in the spinal cord showing low degree or lack of spongy changes. Spongy changes were observed in HCP-treated rats, but not in CPZ-treated rats. Immunohistochemistry showed that intense expression of CNPase was not induced following HCP or CPZ treatment. Our data reveal that expression intensity of CNPase may be dependent on the degree of HCP- and CPZ-induced damage of the myelin sheath.
Assuntos
2',3'-Nucleotídeo Cíclico Fosfodiesterases/metabolismo , Cuprizona/farmacologia , Hexaclorofeno/farmacologia , Medula Espinal/efeitos dos fármacos , Animais , Feminino , Masculino , Bainha de Mielina/efeitos dos fármacos , Bainha de Mielina/patologia , Ratos , Medula Espinal/crescimento & desenvolvimento , Medula Espinal/patologia , Fatores de TempoRESUMO
BACKGROUND: Injectable hyaluronic acid fillers have been widely applied in the clinical treatment of facial wrinkles. However, further information and clinical evidence concerning dermal changes and hyaluronic acid filler longevity after injection and diffusion pattern are limited. METHODS: The authors evaluated the longevity and diffusion pattern of two hyaluronic acid fillers generated by different cross-linking technologies used in the treatment of nasolabial folds using high-frequency ultrasound. Forty-one subjects were treated with Restylane 2 and the remaining 41 were treated with Dermalax DEEP. Wrinkle severity rating scale score and high-frequency ultrasound evaluation of nasolabial folds were performed before and after the injection of hyaluronic acid filler. The ultrasound images were acquired and analyzed to determine dermal thickness and the shape and distribution of hyaluronic acid filler. RESULTS: At 2 and 24 weeks from baseline, increased dermal thickness induced by hyaluronic acid filler treatment was not significantly different between groups. At 48 weeks after injection, increased dermal thicknesses of the Restylane 2 group (0.14 ± 0.12 mm) were much lower than those of the Dermalax DEEP group (0.20 ± 0.13 mm). Ultrasound examination revealed that hyaluronic acid materials form well-demarcated and hypoechogenic areas. Restylane 2 tended to form a more diffuse pattern, with multiple smaller bubbles, whereas Dermalax DEEP developed into a more localized configuration, with larger clumps. CONCLUSIONS: This study is the first long-term assessment of nasolabial fold correction that reveals the performance of different hyaluronic acid materials in vivo and validates high-frequency ultrasound as a simple and rapid modality. Hyaluronic acid fillers generated by different cross-linking technologies display differential diffusion patterns in skin tissues. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, II.
Assuntos
Preenchedores Dérmicos/administração & dosagem , Ácido Hialurônico/uso terapêutico , Sulco Nasogeniano/fisiopatologia , Terapia por Ultrassom/métodos , Adulto , Idoso , Alantoína/uso terapêutico , Técnicas Cosméticas , Combinação de Medicamentos , Estética , Feminino , Seguimentos , Hexaclorofeno/uso terapêutico , Humanos , Ácido Hialurônico/análogos & derivados , Injeções Intradérmicas , Masculino , Pessoa de Meia-Idade , Medição de Risco , Método Simples-Cego , Envelhecimento da Pele/efeitos dos fármacos , Esqualeno/uso terapêutico , Taiwan , Fatores de Tempo , Resultado do TratamentoRESUMO
Chronic hepatitis viral infection, alcoholic intoxication, and obesity cause liver fibrosis, which progresses to decompensated liver cirrhosis, a disease for which medical demands cannot be met. Since there are currently no approved anti-fibrotic therapies for established liver fibrosis, the development of novel modalities is required to improve patient prognosis. In this study, we clarified the anti-fibrotic effects of cell sheets produced from human bone marrow-derived mesenchymal stem cells (MSCs) incubated on a temperature-sensitive culture dish with the chemical compound IC-2. Orthotopic transplantation of IC-2-engineered MSC sheets (IC-2 sheets) remarkably reduced liver fibrosis induced by chronic CCl4 administration. Further, the marked production of fibrolytic enzymes such as matrix metalloproteinase (MMP)-1 and MMP-14, as well as thioredoxin, which suppresses hepatic stellate cell activation, was observed in IC-2 sheets. Moreover, the anti-fibrotic effect of IC-2 sheets was much better than that of MSC sheets. Finally, knockdown experiments revealed that MMP-14 was primarily responsible for the reduction of liver fibrosis. Here, we show that IC-2 sheets could be a promising therapeutic option for established liver fibrosis.
Assuntos
Células da Medula Óssea/citologia , Inibidores Enzimáticos/farmacologia , Cirrose Hepática/terapia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Animais , Compostos Bicíclicos com Pontes/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/terapia , Colágeno Tipo I/metabolismo , Hexaclorofeno/farmacologia , Humanos , Imuno-Histoquímica , Cirrose Hepática/metabolismo , Metaloproteinase 1 da Matriz/metabolismo , Metaloproteinase 14 da Matriz/metabolismo , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , TemperaturaRESUMO
Glucose-regulated protein 78 (GRP78) is the ER resident 70â¯kDa heat shock protein 70 (HSP70) and has been hypothesized to be a therapeutic target for various forms of cancer due to its role in mitigating proteotoxic stress in the ER, its elevated expression in some cancers, and the correlation between high levels for GRP78 and a poor prognosis. Herein we report the development and use of a high throughput fluorescence polarization-based peptide binding assay as an initial step toward the discovery and development of GRP78 inhibitors. This assay was used in a pilot screen to discover the anti-infective agent, hexachlorophene, as an inhibitor of GRP78. Through biochemical characterization we show that hexachlorophene is a competitive inhibitor of the GRP78-peptide interaction. Biological investigations showed that this molecule induces the unfolded protein response, induces autophagy, and leads to apoptosis in a colon carcinoma cell model, which is known to be sensitive to GRP78 inhibition.
Assuntos
Proteínas de Choque Térmico HSP70/efeitos dos fármacos , Hexaclorofeno/uso terapêutico , Ensaios de Triagem em Larga Escala/métodos , Chaperona BiP do Retículo Endoplasmático , Hexaclorofeno/farmacologia , HumanosRESUMO
BACKGROUND: Pressure ulcers, localised injuries to the skin or underlying tissue, or both, occur when people cannot reposition themselves to relieve pressure on bony prominences. These wounds are difficult to heal, painful, expensive to manage and have a negative impact on quality of life. Prevention strategies include nutritional support and pressure redistribution. Dressing and topical agents aimed at prevention are also widely used, however, it remains unclear which, if any, are most effective. This is the first update of this review, which was originally published in 2013. OBJECTIVES: To evaluate the effects of dressings and topical agents on pressure ulcer prevention, in people of any age, without existing pressure ulcers, but considered to be at risk of developing one, in any healthcare setting. SEARCH METHODS: In March 2017 we searched the Cochrane Wounds Group Specialised Register, CENTRAL, MEDLINE, MEDLINE (In-Process & Other Non-Indexed Citations), Embase, and EBSCO CINAHL Plus. We searched clinical trials registries for ongoing trials, and bibliographies of relevant publications to identify further eligible trials. There was no restriction on language, date of trial or setting. In May 2018 we updated this search; as a result several trials are awaiting classification. SELECTION CRITERIA: We included randomised controlled trials that enrolled people at risk of pressure ulcers. DATA COLLECTION AND ANALYSIS: Two review authors independently selected trials, assessed risk of bias and extracted data. MAIN RESULTS: The original search identified nine trials; the updated searches identified a further nine trials meeting our inclusion criteria. Of the 18 trials (3629 participants), nine involved dressings; eight involved topical agents; and one included dressings and topical agents. All trials reported the primary outcome of pressure ulcer incidence.Topical agentsThere were five trials comparing fatty acid interventions to different treatments. Two trials compared fatty acid to olive oil. Pooled evidence shows that there is no clear difference in pressure ulcer incidence between groups, fatty acid versus olive oil (2 trials, n=1060; RR 1.28, 95% CI 0.76 to 2.17; low-certainty evidence, downgraded for very serious imprecision; or fatty acid versus standard care (2 trials, n=187; RR 0.70, 95% CI 0.41 to 1.18; low-certainty evidence, downgraded for serious risk of bias and serious imprecision). Trials reported that pressure ulcer incidence was lower with fatty acid-containing-treatment compared with a control compound of trisostearin and perfume (1 trial, n=331; RR 0.42, 95% CI 0.22 to 0.80; low-certainty evidence, downgraded for serious risk of bias and serious imprecision). Pooled evidence shows that there is no clear difference in incidence of adverse events between fatty acids and olive oil (1 trial, n=831; RR 2.22 95% CI 0.20 to 24.37; low-certainty evidence, downgraded for very serious imprecision).Four trials compared further different topical agents with placebo. Dimethyl sulfoxide (DMSO) cream may increase the risk of pressure ulcer incidence compared with placebo (1 trial, n=61; RR 1.99, 95% CI 1.10 to 3.57; low-certainty evidence; downgraded for serious risk of bias and serious imprecision). The other three trials reported no clear difference in pressure ulcer incidence between active topical agents and control/placebo; active lotion (1 trial, n=167; RR 0.73, 95% CI 0.45 to 1.19), Conotrane (1 trial, n=258; RR 0.74, 95% CI 0.52 to 1.07), Prevasore (1 trial, n=120; RR 0.33, 95% CI 0.04 to 3.11) (very low-certainty evidence, downgraded for very serious risk of bias and very serious imprecision). There was limited evidence from one trial to determine whether the application of a topical agent may delay or prevent the development of a pressure ulcer (DermalexTM 9.8 days vs placebo 8.7 days). Further, two out of 76 reactions occurred in the DermalexTM group compared with none out of 91 in the placebo group (RR 6.14, 95% CI 0.29 to 129.89; very low-certainty evidence; downgraded for very serious risk of bias and very serious imprecision).DressingsSix trials (n = 1247) compared a silicone dressing with no dressing. Silicone dressings may reduce pressure ulcer incidence (any stage) (RR 0.25, 95% CI 0.16 to 0.41; low-certainty evidence; downgraded for very serious risk of bias). In the one trial (n=77) we rated as being at low risk of bias, there was no clear difference in pressure ulcer incidence between silicone dressing and placebo-treated groups (RR 1.95, 95% CI 0.18 to 20.61; low-certainty evidence, downgraded for very serious imprecision).One trial (n=74) reported no clear difference in pressure ulcer incidence when a thin polyurethane dressing was compared with no dressing (RR 1.31, 95% CI 0.83 to 2.07). In the same trial pressure ulcer incidence was reported to be higher in an adhesive foam dressing compared with no dressing (RR 1.65, 95% CI 1.10 to 2.48). We rated evidence from this trial as very low certainty (downgraded for very serious risk of bias and serious imprecision).Four trials compared other dressings with different controls. Trials reported that there was no clear difference in pressure ulcer incidence between the following comparisons: polyurethane film and hydrocolloid dressing (n=160, RR 0.58, 95% CI 0.24 to 1.41); Kang' huier versus routine care n=100; RR 0.42, 95% CI 0.08 to 2.05); 'pressure ulcer preventive dressing' (PPD) versus no dressing (n=74; RR 0.18, 95% CI 0.04 to 0.76) We rated the evidence as very low certainty (downgraded for very serious risk of bias and serious or very serious imprecision). AUTHORS' CONCLUSIONS: Most of the trials exploring the impact of topical applications on pressure ulcer incidence showed no clear benefit or harm. Use of fatty acid versus a control compound (a cream that does not include fatty acid) may reduce the incidence of pressure ulcers. Silicone dressings may reduce pressure ulcer incidence (any stage). However the low level of evidence certainty means that additional research is required to confirm these results.
Assuntos
Bandagens , Úlcera por Pressão/prevenção & controle , Higiene da Pele/métodos , Creme para a Pele/administração & dosagem , Administração Cutânea , Idoso , Alantoína/administração & dosagem , Dimetil Sulfóxido/administração & dosagem , Esquema de Medicação , Combinação de Medicamentos , Ácidos Graxos/administração & dosagem , Hexaclorofeno/administração & dosagem , Humanos , Incidência , Pessoa de Meia-Idade , Azeite de Oliva/administração & dosagem , Úlcera por Pressão/epidemiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Silicones/administração & dosagem , Creme para a Pele/química , Esqualeno/administração & dosagemRESUMO
Maternal hexachlorophene (HCP) exposure causes transient disruption of hippocampal neurogenesis in mouse offspring. We examined epigenetically hypermethylated and downregulated genes related to this HCP-induced disrupted neurogenesis. Mated female mice were dietary exposed to 0 or 100 ppm HCP from gestational day 6 to postnatal day (PND) 21 on weaning. The hippocampal dentate gyrus of male offspring was subjected to methyl-capture sequencing and real-time reverse transcription-polymerase chain reaction analyses on PND 21. Validation analyses on methylation identified three genes, Dlx4, Dmrt1, and Plcb4, showing promoter-region hypermethylation. Immunohistochemically, DLX4+, DMRT1+, and PLCB4+ cells in the dentate hilus co-expressed GAD67, a γ-aminobutyric acid (GABA)ergic neuron marker. HCP decreased all of three subpopulations as well as GAD67+ cells on PND 21. PLCB4+ cells also co-expressed the metabotropic glutamate receptor, GRM1. HCP also decreased transcript level of synaptic plasticity-related genes in the dentate gyrus and immunoreactive granule cells for synaptic plasticity-related ARC. On PND 77, all immunohistochemical cellular density changes were reversed, whereas the transcript expression of the synaptic plasticity-related genes fluctuated. Thus, HCP-exposed offspring transiently reduced the number of GABAergic interneurons. Among them, subpopulations expressing DLX4, DMRT1, or PLCB4 were transiently reduced in number through an epigenetic mechanism. Considering the role of the Dlx gene family in GABAergic interneuron migration and differentiation, the decreased number of DLX4+ cells may be responsible for reducing those GABAergic interneurons regulating neurogenesis. The effect on granule cell synaptic plasticity was sustained until the adult stage, and reduced GABAergic interneurons active in GRM1-PLCB4 signaling may be responsible for the suppression on weaning.
Assuntos
Giro Denteado/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Neurônios GABAérgicos/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Hexaclorofeno/toxicidade , Interneurônios/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal/genética , Animais , Animais Recém-Nascidos , Giro Denteado/embriologia , Feminino , Neurônios GABAérgicos/metabolismo , Interneurônios/metabolismo , Exposição Materna/efeitos adversos , Neurogênese/efeitos dos fármacos , Neurogênese/genética , Plasticidade Neuronal/efeitos dos fármacos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Ácido gama-Aminobutírico/metabolismoRESUMO
Longitudinal MRI employing diffusion tensor imaging and T2 mapping approaches has been applied to investigate the mechanisms of white matter damage caused by acute hexachlorophene neurotoxicity in rats in vivo. Male Sprague-Dawley rats were administered hexachlorophene orally once a day for five consecutive days at a dose of 30mg/kg and were monitored in 7T MRI scanner at days 0 (baseline), 3, 6, 13, and 20 following the first hexachlorophene dose. Quantitative T2 maps as well as a number of diffusion tensor parameters (fractional anisotropy, radial and axial diffusivity, apparent diffusion coefficient, and trace) were calculated from corresponding MR images. T2, as well as all diffusion tensor derived parameters (except fractional anisotropy) showed significant changes during the course of neurotoxicity development. These changes peaked at 6days after the first dose of hexachlorophene (one day after the last dose) and recovered to practically baseline levels at the end of observation (20days from the first dose). While such changes in diffusivity and T2 relaxation clearly demonstrate myelin perturbations consistent with edema, the lack of changes of fractional anisotropy suggests that the structure of the myelin sheath was not disrupted significantly by hexachlorophene in this study. This is also confirmed by the rapid recovery of all observed MRI parameters after cessation of hexachlorophene exposure.
Assuntos
Anti-Infecciosos Locais/farmacologia , Encéfalo/efeitos dos fármacos , Encéfalo/diagnóstico por imagem , Imagem de Tensor de Difusão , Hexaclorofeno/farmacologia , Animais , Anisotropia , Processamento de Imagem Assistida por Computador , Estudos Longitudinais , Masculino , Fibras Nervosas Mielinizadas/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Substância Branca/diagnóstico por imagem , Substância Branca/efeitos dos fármacosRESUMO
Lactic acid bacteria (LAB) isolated throughout the fermentation process of Aloreña table olives were found to be resistant at least to three antibiotics (Casado Muñoz et al., 2014); however, most were sensitive to the biocides tested in this study (with minimum inhibitory concentrations [MIC] below the epidemiological cut-off values). 2-15% of the isolates were found to be biocide resistant: Leuconostoc Pseudomesenteroides, which were resistant to hexachlorophene, and Lactobacillus pentosus to cetrimide and hexadecylpiridinium. We analyzed the effect of different physico-chemical stresses, including antimicrobials, on the phenotypic and genotypic responses of LAB, providing new insights on how they become resistant in a changing environment. Results indicated that similar phenotypic responses were obtained under three stress conditions: antimicrobials, chemicals and UV light. Susceptibility patterns to antibiotics changed: increasing MICs for ampicillin, chloramphenicol, ciprofloxacin, teicoplanin and tetracycline, and decreasing the MICs for clindamycin, erythromycin, streptomycin and trimethoprim in most strains. Statistically, cross resistance between different antibiotics was detected in all stress conditions. However, expression profiles of selected genes involved in stress/resistance response (rpsL, recA, uvrB and srtA) differed depending on the stress parameter, LAB species and strain, and the target gene. We conclude that, despite the uniform phenotypic response to stresses, the repertoire of induced and repressed genes differs. So, a search for a target to improve stress tolerance of LAB, especially those of importance as starter/protective cultures or probiotics, may depend on the individual screening of each strain, even though we could predict the antibiotic phenotypic response to all stresses.
Assuntos
Anti-Infecciosos Locais/farmacologia , Desinfetantes/farmacologia , Fermentação , Lactobacillaceae/efeitos dos fármacos , Lactobacillaceae/genética , Olea/microbiologia , Aminoaciltransferases/genética , Proteínas de Bactérias/genética , Cetrimônio , Compostos de Cetrimônio/farmacologia , Cetilpiridínio/farmacologia , Cisteína Endopeptidases/genética , Microbiologia de Alimentos , Hexaclorofeno/farmacologia , Lactobacillaceae/isolamento & purificação , Lactobacillaceae/efeitos da radiação , Lactobacillus/efeitos dos fármacos , Lactobacillus/genética , Lactobacillus/isolamento & purificação , Leuconostoc/efeitos dos fármacos , Leuconostoc/isolamento & purificação , Testes de Sensibilidade Microbiana , Fenótipo , Probióticos/isolamento & purificação , Probióticos/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Recombinases Rec A/genética , Estresse Fisiológico/genéticaRESUMO
The aim of this randomized controlled trial was to assess the efficacy of a cream containing ceramides and magnesium (Cer-Mg) in the treatment of mild to moderate atopic dermatitis and to compare it with hydrocortisone and a commonly used emollient (unguentum leniens; cold cream). A total of 100 patients, randomized into 2 groups, were treated for 6 weeks simultaneously (left vs. right side of the body) with either Cer-Mg and hydrocortisone (group I) or Cer-Mg and emollient (group II). The primary outcome was a reduction in severity of lesions as assessed by (local) SCORAD (SCORing Atopic Dermatitis). Levels of trans-epidermal water loss (TEWL), skin hydration, and natural moisturizing factors (NMF) were then measured. After 6 weeks, group I showed comparable significant improvement in SCORAD and TEWL, while in group II, the decrease in SCORAD and TEWL was significantly greater after Cer-Mg compared with emollient. Finally, Cer-Mg cream was more effective in improving skin hydration and maintenance of levels of NMF than hydrocortisone and emollient.
Assuntos
Alantoína/uso terapêutico , Dermatite Atópica/tratamento farmacológico , Emolientes , Hexaclorofeno/uso terapêutico , Hidrocortisona/uso terapêutico , Pomadas , Esqualeno/uso terapêutico , Adulto , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
BACKGROUND AND PURPOSE: High-throughput screening of compound libraries using genetically encoded fluorescent biosensors has identified several second-generation. low MW inhibitors of the calcium-activated chloride channel anoctamin 1 (CaCC/Ano1). Here we have (i) examined the effects of these Ano1 inhibitors on gastric and intestinal pacemaker activity; (ii) compared the effects of these inhibitors with those of the more classical CaCC inhibitor, 5-nitro-2-(3-phenylpropylalanine) benzoate (NPPB); (ii) examined the mode of action of these compounds on the waveform of pacemaker activity; and (iii) compared differences in the sensitivity between gastric and intestinal pacemaker activity to the Ano1 inhibitors. EXPERIMENTAL APPROACH: Using intracellular microelectrode recordings of gastric and intestinal muscle preparations from C57BL/6 mice, the dose-dependent effects of Ano1 inhibitors were examined on spontaneous electrical slow waves. KEY RESULTS: The efficacy of second-generation Ano1 inhibitors on gastric and intestinal pacemaker activity differed significantly. Antral slow waves were more sensitive to these inhibitors than intestinal slow waves. CaCCinh -A01 and benzbromarone were the most potent at inhibiting slow waves in both muscle preparations and more potent than NPPB. Dichlorophene and hexachlorophene were equally potent at inhibiting slow waves. Surprisingly, slow waves were relatively insensitive to T16Ainh -A01 in both preparations. CONCLUSIONS AND IMPLICATIONS: We have identified several second-generation Ano1 inhibitors, blocking gastric and intestinal pacemaker activity. Different sensitivities to Ano1 inhibitors between stomach and intestine suggest the possibility of different splice variants in these two organs or the involvement of other conductances in the generation and propagation of pacemaker activity in these tissues.