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1.
Graefes Arch Clin Exp Ophthalmol ; 253(3): 425-30, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25398660

RESUMO

PURPOSE: Increased levels of oxidative stress have been seen in animal models of dry eye and in the conjunctival epithelial cells of patients with Sjögren's syndrome. The aims of this study were to compare the levels of oxidative stress in patients with dry eye and patients without dry eye and to evaluate the effects of treatment with preservative-free eye drops containing hyaluronic acid 0.15 % and vitamin B12 on oxidative stress and dry eye symptoms. METHODS: Three cohorts of patients who were to undergo planned cataract surgery were enrolled: patients with dry eye randomized to either no treatment (n = 29) or treatment (n = 32) with hyaluronic acid/vitamin B12 eye drops, and patients without dry eye (n = 42). Patients were assessed by Schirmer's type I test, fluorescein clearance test (FCT), Break Up Time (BUT), and Ocular Surface Disease Index (OSDI). Lipid peroxidation, a marker of oxidative stress, was assessed by LP-CHOLOX test. RESULTS: Compared with patients without dry eye, patients with dry eye had significantly increased levels of oxidative stress, higher OSDI and FCT scores, and significantly lower Schirmer's test and BUT scores. Treatment with eye drops containing hyaluronic acid 0.15 % and vitamin B12 was associated with significantly reduced levels of oxidative stress and OSDI and FCT scores and significantly increased Schirmer's test and BUT scores. CONCLUSIONS: These findings indicate that oxidative stress is associated with dry eye and that hyaluronic acid/vitamin B12 eye drops may attenuate oxidative stress and inflammation, improving dry eye symptoms. Further study in controlled clinical trials is warranted.


Assuntos
Túnica Conjuntiva/efeitos dos fármacos , Síndromes do Olho Seco/tratamento farmacológico , Ácido Hialurônico/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Viscossuplementos/administração & dosagem , Vitamina B 12/administração & dosagem , Complexo Vitamínico B/administração & dosagem , Administração Tópica , Idoso , Túnica Conjuntiva/metabolismo , Combinação de Medicamentos , Síndromes do Olho Seco/metabolismo , Epitélio/efeitos dos fármacos , Epitélio/metabolismo , Feminino , Humanos , Peroxidação de Lipídeos , Masculino , Soluções Oftálmicas , Concentração Osmolar , Conservantes Farmacêuticos , Estudos Prospectivos , Lágrimas/química
2.
Altern Lab Anim ; 41(6): 491-502, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24512233

RESUMO

The presence of waste in the environment has frequently been indicated as a significant risk to human health. Therefore, landfill sites and the disposal of urban solid and non-hazardous waste by incineration are subject to much environmental monitoring, in addition to the regulations already in place. However, little action has been taken, and consequently no specific legislation exists, in relation to the assessment of the real biological risk of various substances, including chemical mixtures and ashes, derived from the incineration processes. This study assessed the cytotoxic potential of humid lightweight coal ash (LA) derived from incineration processes and waste management, on two cell lines: NCTC 2544 normal human keratinocytes and HECV endothelial cells. To reach this goal and to assess more-realistic methods for animal replacement, we employed different in vitro experimental approaches: acute and longer exposure to LA, by direct and indirect contact (0-2mg/ml and 16mg, respectively), both in 2-D and 3-D cultures. In 2-D HECV cultures, we observed a decrease in the viability index, but only during direct contact with LA doses higher than 0.1mg/ml. Moreover, some striking differences in cytotoxicity were observed between the 2-D and 3-D models. Taken together, these observations indicate that, for studying pollutant toxicity during longer exposure times, 3-D cultures in direct contact with the pollutant seem to offer a more suitable approach - they mimic the in vivo behaviour of cells more realistically and under strictly controlled conditions. Thus, in readiness for possible forthcoming European regulations, we believe that the proposed study, even in its preliminary phase, can provide new advice on the assessment of the toxic and biological potential of particular chemical compounds derived from waste management processes.


Assuntos
Cinza de Carvão/toxicidade , Células Endoteliais/efeitos dos fármacos , Queratinócitos/efeitos dos fármacos , Células Cultivadas , Humanos , Umidade , Técnicas In Vitro
3.
Cell Biol Int ; 33(5): 594-601, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19286468

RESUMO

A great effort has recently been made to obtain human stem cells able to differentiate into cholinergic neurons, as a number of diseases are associated to the cholinergic neuron loss, degeneration or incorrect function (Alzheimer's disease and motor neuron disease). A stem cell population (i.e. pre-adipocytes) is present in the adipose stromal compartment. Pre-adipocytes, like the mesodermic derivative cells, retain high plasticity and potentiality to convert in vitro from one phenotype into many others, and they can be isolated from adult adipose tissue. Pre-adipocytes committed in vitro to neural differentiation were followed up to the acquisition of neural morphology. Acetylcholinesterase and choline acetyltransferase are expressed from the native cell stage, with different localisations and roles during neural commitment. Western blots show the beginning of a new synthesis of these enzymes at 4 weeks of culture of neurogenic pre-adipocytes, in parallel with neural morphology. The passage of the choline-acetyltransferase immunoreactivity from cytoplasmic to membrane localisation shows the possible onset of catalytic activity and the histochemical reaction confirms the activity of acetylcholinesterase. This explains the possibility of obtaining cholinergic-like phenotype from pre-adipocytes.


Assuntos
Acetilcolina/metabolismo , Adipócitos/metabolismo , Adipócitos/fisiologia , Neurogênese/fisiologia , Células-Tronco/metabolismo , Células-Tronco/fisiologia , Acetilcolinesterase/metabolismo , Adipócitos/citologia , Animais , Diferenciação Celular/fisiologia , Células Cultivadas , Colina O-Acetiltransferase/metabolismo , Humanos , Neurônios/citologia , Neurônios/metabolismo , Receptores Nicotínicos/metabolismo , Células-Tronco/citologia
4.
Heliyon ; 3(2): e00251, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28239674

RESUMO

Oxidative stress exerts major role in the pathogenesis of side effects of many antineoplastic drugs, including ototoxicity of cisplatin. In particular, increased levels of reactive oxygen species (ROS) represent one of the molecular mechanisms underlying the apoptosis of different types of hearing cells. Antioxidants and ROS scavengers may thus represent potential therapeutic options to prevent platinum-associated ototoxicity. The aim of this preliminary case-control study was to explore the efficacy of a dietary antioxidant supplement, in order to hamper the occurrences of ototoxicity in patients undergoing cisplatin chemotherapy. As results, a significant protection against cochlear toxic damage was demonstrated in patients who took the antioxidant supplement, which furthermore prevented the occurrence of hearing disorders and tinnitus. These clinical evidences were corroborated by the oxidative status of patients. After cisplatin chemotherapy, the plasma derivatives of reactive oxygen metabolites (d-ROMs) content rapidly increased in control patients, but it was maintained in those under dietary supplementation, likely because of a higher anti-ROMs potential. Indeed, an increment in rapid anti-ROMs was detected in supplemented patients, though no differences were highlighted in terms of slow anti-ROMs. In conclusion, in this preliminary report we demonstrated the feasibility of a dietary antioxidant supplementation in order to prevent the cisplatin induced hearing damage.

5.
Artigo em Inglês | MEDLINE | ID: mdl-26736819

RESUMO

A reactive oxygen species-mediated targeting system has been used to selectively kill cancer cells. Two different cell lines, normal and cancer cells, have been cultured and treated with a peroxide olive oil (K600) in simple solution and in form of nanoemulsion (N-K600). Preliminary results of both treatments have been compared.


Assuntos
Emulsões/química , Nanoestruturas/química , Azeite de Oliva/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Emulsões/uso terapêutico , Emulsões/toxicidade , Humanos , Peroxidação de Lipídeos , Nanoestruturas/uso terapêutico , Nanoestruturas/toxicidade , Neoplasias/tratamento farmacológico , Espécies Reativas de Oxigênio/metabolismo
6.
Respir Physiol Neurobiol ; 194: 54-61, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24495442

RESUMO

Lung diffusing capacity for CO (DLCO) is compromised in haematopoietic stem-cell transplantation (HSCT) recipients. We derived alveolar-capillary membrane conductance (DM,CO) and pulmonary capillary volume (VC) from DLCO and diffusing capacity for NO (DLNO). Forty patients were studied before and 6 weeks after HSCT. Before HSCT, DLNO and DLCO were significantly lower than in 30 healthy controls. DM,CO was ∼40% lower in patients than in controls (p<0.001), whereas VC did not differ significantly. After HSCT, DLNO and DM,CO further decreased, the latter by ∼22% from before HSCT (p<0.01) while VC did not change significantly. Lung density, serum CRP and reactive oxygen metabolites were significantly increased, with the latter being correlated (R2=0.71, p<0.001) with the decrement in DLNO. We conclude that DLNO and, to a lesser extent, DLCO are compromised before HSCT mainly due to a DM,CO reduction. A further reduction of DM,CO without VC loss occurs after HSCT, possibly related to development of oedema, or interstitial fibrosis, or both.


Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Pulmão/fisiopatologia , Capacidade de Difusão Pulmonar/fisiologia , Adolescente , Adulto , Idoso , Gasometria , Proteína C-Reativa/metabolismo , Feminino , Humanos , Pulmão/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Espécies Reativas de Oxigênio/sangue , Testes de Função Respiratória , Espirometria , Tomografia Computadorizada por Raios X , Adulto Jovem
10.
Toxicol Lett ; 192(2): 101-7, 2010 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-19878710

RESUMO

According to European laws animal testing in cosmetic industry will be prohibited in a few years and it will be replaced by alternative methods based on cell and tissue culture. Many ingredients of cosmetic formulations are potentially causes of skin inflammation and sensibilization. Since cytotoxicity is known, among other factors, to trigger irritation, in an alternative model for evaluation of skin irritation, it can be considered also the precocious release of inflammatory mediators, i.e. cytokines, originating mainly from keratinocytes. In this in vitro study we have analysed some parameters directly or indirectly related to irritation/inflammation, in NCTC 2544 human keratinocytes during short-time exposure to some potential irritants cosmetic fragrances, included in the European Laws 2003/15/EEC. IIC50 was extrapolated by MTT and NRU viability indexes after exposure of cell ultures to Geraniol Limonene and Benzylic Alcohol for 1, 3 and 6h. NCTC cells were then exposed to sub-toxic doses of selected compounds and interleukin-1alpha (IL-1alpha) and leukaemia inhibitory factor (LIF) expressions were analysed as early proinflammatory cytokines. To our knowledge our findings demonstrated for the first time that NCTC cells synthesize and modulate LIF after exposure to selected irritating stimuli. Moreover, our results give evidence on LIF role as in vitro precocious endpoint for the assessment of the risk in cosmetic field, because its response under irritation stimuli is very quick and comparable to IL-1alpha.


Assuntos
Álcool Benzílico/toxicidade , Cicloexenos/toxicidade , Interleucina-1alfa/metabolismo , Fator Inibidor de Leucemia/metabolismo , Perfumes/toxicidade , Terpenos/toxicidade , Monoterpenos Acíclicos , Biomarcadores/metabolismo , Linhagem Celular , Relação Dose-Resposta a Droga , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Limoneno , Testes de Irritação da Pele/métodos , Dodecilsulfato de Sódio/toxicidade
11.
Chem Biol Interact ; 184(3): 474-83, 2010 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-20080079

RESUMO

Stem cell models offer an opportunity both for therapeutic use and for the assessment of alternative in vitro models. Human lipoaspirate is a source of adult stem cells (pre-adipocytes), which are able to differentiate into various phenotypes, such as neurogenic lineage. Here, we analyse the suitability of these in vitro models in screening exogenous compounds, such as environmental pollutants, that may affect adipose cells and neurogenic development. To evaluate neurogenic differentiation, we analysed expression of cholinergic system and acetylcholinesterase immunoreactivity. Heterocyclic derivatives of polycyclic aromatic hydrocarbons (PAHs) are often significant components of environmental contaminants. As they contain inducers of cytochrome P450 1A1 (CYP1A1), we explored the activity of CYP1A1-related enzymes, i.e. 7-ethoxycoumarin- and 7-ethoxyresorufin-O-deethylase (ECOD and EROD) in both cell systems in basal conditions and after exposure to non-cytotoxic doses of beta-naphthoflavone (BNF), a well-known PAH-type inducer. Both cell models showed basal and inducible levels of ECOD. Analysis of CYP1A1 protein expression and EROD-related enzyme activity confirmed the inducibility of the CYP1A1 isoform by BNF. These results demonstrate that mesenchymal adult stem cells can constitute innovative models. We therefore propose the use of pre-adipocytes and their neurogenic derivates to evaluate the cytotoxic/biological effects of unintended exposure to contaminants.


Assuntos
Adipócitos/citologia , Células-Tronco Adultas/enzimologia , Citocromo P-450 CYP1A1/metabolismo , Neurônios/enzimologia , O-Dealquilase 7-Alcoxicumarina/metabolismo , Acetiltransferases/metabolismo , Adipócitos/enzimologia , Células-Tronco Adultas/citologia , Diferenciação Celular , Poluentes Ambientais/toxicidade , Inibidores Enzimáticos/toxicidade , Citometria de Fluxo , Humanos , Neurônios/citologia , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Isoformas de Proteínas/metabolismo , beta-Naftoflavona/toxicidade
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