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1.
Antioxidants (Basel) ; 12(3)2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36979005

RESUMO

Cerium oxide nanoparticles (nanoceria), biocompatible multifunctional nanozymes exerting unique biomimetic activities, mimic superoxide-dismutase and catalase through a self-regenerating, energy-free redox cycle driven by Ce3+/4+ valence switch. Additional redox-independent UV-filter properties render nanoceria ideal multitask solar screens, shielding from UV exposure, simultaneously protecting tissues from UV-oxidative damage. Here, we report that nanoceria favour basal proliferation of primary normal keratinocytes, and protects them from UVB-induced DNA damage, mutagenesis, and apoptosis, minimizing cell loss and accelerating recovery with flawless cells. Similar cell-protective effects were found on irradiated noncancerous, but immortalized, p53-null HaCaT keratinocytes, with the notable exception that here, nanoceria do not accelerate basal HaCaT proliferation. Notably, nanoceria protect HaCaT from oxidative stress induced by irradiated titanium dioxide nanoparticles, a major active principle of commercial UV-shielding lotions, thus neutralizing their most critical side effects. The intriguing combination of nanoceria multiple beneficial properties opens the way for smart and safer containment measures of UV-induced skin damage and carcinogenesis.

2.
Int J Mol Sci ; 24(3)2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36768364

RESUMO

Androgen deprivation therapy (ADT) is a powerful treatment for metastatic hormone-sensitive prostate cancer (mHSPC) patients, but eventually and inevitably, cancer relapses, progressing to the fatal castration-resistant (CR)PC stage. Progression implies the emergence of cells proliferating in the absence of androgen through still elusive mechanisms. We show here for the first time that ADT induces LNCaP mHSPC cells to collectively enter a metastable quasi-apoptotic state (QUAPS) consisting of partial mitochondrial permeabilization, limited BAX and caspase activation, and moderate induction of caspase-dependent dsDNA breaks; despite this, cells maintain full viability. QUAPS is destabilized by poly(ADP)-polymerase inhibition (PARPi), breaking off toward overt intrinsic apoptosis and culture extinction. Instead, QUAPS is rapidly and efficiently reverted upon androgen restoration, with mitochondria rapidly recovering integrity and cells collectively resuming normal proliferation. Notably, replication restarts before DNA repair is completed, and implies an increased micronuclei frequency, indicating that ADT promotes genetic instability. The recovered cells re-acquire insensitivity to PARPi (as untreated LNCaP), pointing to specific, context-dependent vulnerability of mHSPC cells to PARPi during ADT. Summarizing, QUAPS is an unstable, pro-mutagenic state developing as a pro-survival pathway stabilized by PARP, and constitutes a novel viewpoint explaining how ADT-treated mHSPC may progress to CRPC, indicating possible preventive countermeasures.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Androgênios , Antagonistas de Androgênios/farmacologia , Poli(ADP-Ribose) Polimerases/genética , Recidiva Local de Neoplasia , Apoptose , Caspases
3.
Int J Mol Sci ; 23(3)2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35163077

RESUMO

Apoptotic cells stimulate compensatory proliferation through the caspase-3-cPLA-2-COX-2-PGE-2-STAT3 Phoenix Rising pathway as a healing process in normal tissues. Phoenix Rising is however usurped in cancer, potentially nullifying pro-apoptotic therapies. Cytotoxic therapies also promote cancer cell plasticity through epigenetic reprogramming, leading to epithelial-to-mesenchymal-transition (EMT), chemo-resistance and tumor progression. We explored the relationship between such scenarios, setting-up an innovative, straightforward one-pot in vitro model of therapy-induced prostate cancer repopulation. Cancer (castration-resistant PC3 and androgen-sensitive LNCaP), or normal (RWPE-1) prostate cells, are treated with etoposide and left recovering for 18 days. After a robust apoptotic phase, PC3 setup a coordinate tissue-like response, repopulating and acquiring EMT and chemo-resistance; repopulation occurs via Phoenix Rising, being dependent on high PGE-2 levels achieved through caspase-3-promoted signaling; epigenetic inhibitors interrupt Phoenix Rising after PGE-2, preventing repopulation. Instead, RWPE-1 repopulate via Phoenix Rising without reprogramming, EMT or chemo-resistance, indicating that only cancer cells require reprogramming to complete Phoenix Rising. Intriguingly, LNCaP stop Phoenix-Rising after PGE-2, failing repopulating, suggesting that the propensity to engage/complete Phoenix Rising may influence the outcome of pro-apoptotic therapies. Concluding, we established a reliable system where to study prostate cancer repopulation, showing that epigenetic reprogramming assists Phoenix Rising to promote post-therapy cancer repopulation and acquired cell-resistance (CRAC).


Assuntos
Apoptose , Reprogramação Celular , Resistencia a Medicamentos Antineoplásicos , Epigênese Genética , Etoposídeo/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias da Próstata/patologia , Antineoplásicos Fitogênicos/farmacologia , Transição Epitelial-Mesenquimal , Humanos , Masculino , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Transdução de Sinais , Células Tumorais Cultivadas
4.
Metabolites ; 13(1)2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36676990

RESUMO

Prostate cancer at the castration-resistant stage (CRPC) is a leading cause of death among men due to resistance to anticancer treatments, including chemotherapy. We set up an in vitro model of therapy-induced cancer repopulation and acquired cell resistance (CRAC) on etoposide-treated CRPC PC3 cells, witnessing therapy-induced epithelial-to-mesenchymal-transition (EMT) and chemoresistance among repopulating cells. Here, we explore the metabolic changes leading to chemo-induced CRAC, measuring the exchange rates cell/culture medium of 36 metabolites via Nuclear Magnetic Resonance spectroscopy. We studied the evolution of PC3 metabolism throughout recovery from etoposide, encompassing the degenerative, quiescent, and repopulating phases. We found that glycolysis is immediately shut off by etoposide, gradually recovering together with induction of EMT and repopulation. Instead, OXPHOS, already high in untreated PC3, is boosted by etoposide to decline afterward, though stably maintaining values higher than control. Notably, high levels of EMT, crucial in the acquisition of chemoresistance, coincide with a strong acceleration of metabolism, especially in the exchange of principal nutrients and their end products. These results provide novel information on the energy metabolism of cancer cells repopulating from cytotoxic drug treatment, paving the way for uncovering metabolic vulnerabilities to be possibly pharmacologically targeted and providing novel clinical options for CRPC.

5.
Epilepsy Res ; 83(2-3): 112-6, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19081227

RESUMO

PURPOSE: To report on the first multicenter Italian experience with zonisamide as an add-on drug for refractory generalised or partial epilepsy in children, adolescents and young adults. METHODS: The patients were enrolled in a prospective, add-on, open-label treatment study from eight Italian centres for children and adolescent epilepsy care. Eighty-two young patients (45 males, 37 females), aged between 3 and 34 years (mean 13.1 years), all affected by partial (47) or generalised (35) refractory epilepsy, were enrolled in the study. ZNS was added to the baseline therapy at a starting dose of 1 mg/kg/day twice daily. This dose was increased by 2 mg/kg every 1-2 weeks over a period of up 3 months, according to the patient's response and tolerability, up to a maximum dose of 12 mg/kg. ZNS was given at the mean daily dose of 5.7/mg/kg/24 h (range 1-12 mg/kg). RESULTS: After a mean follow-up period of 11.9 months (range 2-64 months), 9 patients (10.9%) were seizure-free. The number of seizures decreased by 50-99% in 31 cases (37.8%), by 25-49% in 5 cases (6.1%), remained the same in 29 cases (35.4%) and increased in 8 cases (9.7%). After 15 months of follow-up, 61 patients (74.4%) were still taking ZNS, while the remaining 21 (25.6%) had stopped. Twenty-two patients (26.8%) reported adverse effects while taking ZNS. They generally appeared during the first weeks of treatment, and were mild to moderate. The most frequent adverse effects were irritability and a reduced appetite. CONCLUSION: ZNS effectively reduced seizure frequency in this pediatric population with both partial and generalised crypto/symptomatic refractory epilepsy. Its overall tolerability was good.


Assuntos
Anticonvulsivantes/uso terapêutico , Epilepsia/tratamento farmacológico , Isoxazóis/uso terapêutico , Adolescente , Adulto , Criança , Pré-Escolar , Tolerância a Medicamentos , Eletroencefalografia/métodos , Epilepsia/mortalidade , Feminino , Seguimentos , Humanos , Itália , Imageamento por Ressonância Magnética/métodos , Masculino , Exame Neurológico/métodos , Estatísticas não Paramétricas , Adulto Jovem , Zonisamida
6.
Epilepsy Res ; 82(2-3): 200-10, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18976884

RESUMO

PURPOSE: In the Littoral Province of Cameroon, in the Sanaga River Valley, a door-to-door epidemiological study was carried out in order to evaluate the prevalence of epilepsy in a small village located in a geographically isolated area, hyper-endemic for onchocerciasis. It was followed by an electro-clinical evaluation of patients and a case-control study. METHODS: The study involved a three-phases design: in phase I, a screening questionnaire was administered, in phase II, the presence of epilepsy was confirmed with electro-clinical evaluation, and in phase III, risk factors for epilepsy, socio-economical factors and life habits were evaluated in patients and two matched controls for the age (+/-1 year) residents in the same village. Endemicity level of onchocerciasis was assessed in the village by measuring the prevalence of nodules in adult males aged >or=20 years (PNAM). RESULTS: One hundred eighty-one subjects (100 male and 81 female) were examined (91.9% of the overall population). The crude prevalence rate of active epilepsy was 105 per 1000 pop (CI 95% 60-150) while the age-adjusted prevalence rate was 134.5 cases per 1000 pop (CI 95% 90-178). Seizures were classified as generalized in 10 patients (52.6%) and partial in nine (47.4%). In 17 patients EEG was recorded. Afterward the electro-clinical classification this distribution was inverted: generalized seizures occurred in 35.3% of cases and partial seizures in 64.7% of cases. The PNAM was 62.5%. The surveyed village was classified as hyper-endemic for onchocerciasis. Among risk factors, only positive family history for epilepsy was found (p=0.031). A sample pedigree of a family with 10 epileptic cases (4 included in the epidemiological study) was showed. CONCLUSIONS: To our knowledge, this is the first door-to-door study that produce an adjusted prevalence rate on epilepsy in Cameroon. In according to studies done in Tanzania, Liberia, Uganda, and Ethiopia, our results (i.e., the high prevalence rate in a restricted area, the clinical characteristics of epileptic seizures, the positive family history for epilepsy and the type of pedigree of a family with epileptic patients) may be accounted for by the presence of an strong interaction between environmental and genetic factors in some circumscribed areas.


Assuntos
Epilepsia/epidemiologia , Adolescente , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Camarões/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Comorbidade , Eletroencefalografia , Doenças Endêmicas , Epilepsia/etnologia , Epilepsia/etiologia , Epilepsia/genética , Etnicidade/genética , Etnicidade/estatística & dados numéricos , Feminino , Predisposição Genética para Doença , Hábitos , Inquéritos Epidemiológicos , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Oncocercose/epidemiologia , Linhagem , Prevalência , Fatores de Risco , População Rural , Fatores Socioeconômicos , Adulto Jovem
7.
Neurol Sci ; 29(4): 285-7, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18810607

RESUMO

We designed a 3-month open label trial of melatonin prophylaxis in children with primary headache. After a one month baseline period without receiving preventive drugs, all children received a 3-month course of melatonin, 3 mg, administered orally, at bedtime. A total of 22 children were enrolled (10 boys, mean age 12.2+/-2.6 years, age range 6-16 years), 13 had recurrent migraine without aura, 1 with aura and 8 had chronic tension-type headache. When the trial ended, 14 of the 21 subjects reported that the headache attacks had decreased by more than 50% in respect to baseline and 4 of them reported having no headache attacks. After receiving melatonin for one month one subject dropped out because of excessive daytime sleepiness. Our promising results warrant randomized placebo-controlled trials in children to assess the real effectiveness of melatonin in preventing primary headache.


Assuntos
Melatonina/administração & dosagem , Transtornos de Enxaqueca/tratamento farmacológico , Cefaleia do Tipo Tensional/tratamento farmacológico , Adolescente , Fatores Etários , Depressores do Sistema Nervoso Central/administração & dosagem , Depressores do Sistema Nervoso Central/efeitos adversos , Criança , Transtornos da Consciência/induzido quimicamente , Feminino , Humanos , Masculino , Melatonina/efeitos adversos , Transtornos de Enxaqueca/prevenção & controle , Fases do Sono/efeitos dos fármacos , Cefaleia do Tipo Tensional/prevenção & controle , Resultado do Tratamento
8.
J Child Neurol ; 23(1): 124-8, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18079319

RESUMO

We describe an obese child with severe obstructive sleep apnea syndrome in whom nocturnal frontal lobe seizures developed within a week after therapy was started with continuous positive airway pressure. The video polysomnographic study after the onset of nocturnal episodes showed 3 seizures: 2 starting from slow-wave sleep when he was sleeping with continuous positive airway pressure, and 1 from stage 2 non-rapid eye movement sleep when he was sleeping without continuous positive airway pressure. Cyclic alternating pattern analysis during the video polysomnography recorded after the onset of nocturnal seizures disclosed a high cyclic alternating pattern rate during slow-wave sleep, and the recording obtained after antiepileptic therapy began showed a low cyclic pattern analysis rate. In this child, we describe the non-rapid eye movement sleep instability induced by continuous positive airway pressure therapy might have had a role in triggering the nocturnal seizures.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas/efeitos adversos , Epilepsia/etiologia , Epilepsia/fisiopatologia , Lobo Frontal/fisiopatologia , Apneia Obstrutiva do Sono/terapia , Pré-Escolar , Eletroencefalografia , Humanos , Masculino , Obesidade/complicações , Periodicidade , Polissonografia , Sono/fisiologia , Transtornos do Sono-Vigília/complicações , Transtornos do Sono-Vigília/fisiopatologia , Sono REM/fisiologia
9.
Epilepsia ; 48(11): 2181-6, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17711460

RESUMO

We report the history of a 14-year-old girl with atypical childhood occipital epilepsy "Gastaut type" whose first generalized tonic-clonic seizure was preceded by migraine without aura and followed by a status migrainosus. This status lasted for 3 days despite standard analgesic therapy. An EEG recording revealed an occipital status epilepticus during her migraine complaints. Seven minutes after intravenous administration of 10 mg diazepam under continuous EEG recording, a suppression of the epileptiform discharges over the right occipital was seen, while the headache subsided 3 min later. After precise questioning about the circumstances that possibly could have led to these events, it appeared that she had played for hours with a play station on the new color TV and she had visited an exhibition of Matisse and Bonnard with bright colors and contrast-rich text. Standardized extensive intermittent photic stimulation (IPS), 2 days after the status migrainosus, evoked besides asymmetrical right-sided driving, green spots in her left visual field, while in the EEG sharp waves were recorded over the right parietotemporal region. After further IPS with 20 Hz (eye closure), she started complaining of a light pulsating headache right occipitally and in the EEG right parietotemporal sharp-waves were seen. This lasted for about 10 min. Later, an interictal routine EEG was normal except for some theta over the right temporooccipital area. The most likely diagnosis is an atypical form of occipital epilepsy "Gastaut type." We would therefore advocate recording EEGs with photic stimulation in patients with atypical migraneous features.


Assuntos
Anticonvulsivantes/uso terapêutico , Diazepam/uso terapêutico , Epilepsias Parciais/tratamento farmacológico , Transtornos de Enxaqueca/tratamento farmacológico , Adolescente , Anticonvulsivantes/provisão & distribuição , Comorbidade , Diazepam/administração & dosagem , Eletroencefalografia/estatística & dados numéricos , Epilepsias Parciais/epidemiologia , Epilepsia Reflexa/tratamento farmacológico , Epilepsia Reflexa/psicologia , Epilepsia Tônico-Clônica/tratamento farmacológico , Epilepsia Tônico-Clônica/psicologia , Feminino , Lateralidade Funcional/fisiologia , Humanos , Injeções Intravenosas , Transtornos de Enxaqueca/epidemiologia , Estimulação Luminosa , Estado Epiléptico/tratamento farmacológico , Estado Epiléptico/psicologia , Resultado do Tratamento
11.
Epilepsy Res ; 59(1): 35-42, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15135165

RESUMO

PURPOSE: To evaluate the efficacy and safety of levetiracetam (LEV) in refractory crypto/symptomatic, partial or generalised epilepsy in children, adolescents and young adults. METHODS: We performed a prospective open label add-on study in 99 patients (age 12 months to 32 years, mean 14 years) with partial or generalised, crypto/symptomatic seizures. Levetiracetam was added to no more than two baseline AEDs and the efficacy was rated according to seizure type and frequency. RESULTS: LEV was initiated at the starting dose of 10mg/kg/day with 5-day increments up to 50 mg/kg/day, unless it was not tolerated. Concomitant therapy was generally not modified throughout the study. After a mean follow-up period of 6.7 months (range 3 weeks to 29 months), 11 patients (11.1%) were free of seizures (cryptogenic partial epilepsy, 5; symptomatic partial epilepsy, 6). A more than 75% seizure decrease was found in 14 patients (14.1%) and >50% in 8 (8.1%). Seizures were unchanged in 38 (38.4%), and worsened in 23 (23.2%). Mild and transient adverse side effects were found in 17 patients (17.2%), mostly represented by irritability and drowsiness. CONCLUSION: LEV appears to be well tolerated in children and adolescents with severe epilepsy and seems to be a broad spectrum AED, though in our experience, it was more effective against partial seizures with or without secondarily generalisation. LEV efficacy in other epilepsy syndrome should be evaluated further in homogeneous, more selected patients.


Assuntos
Epilepsia/tratamento farmacológico , Piracetam/uso terapêutico , Adolescente , Adulto , Distribuição de Qui-Quadrado , Criança , Pré-Escolar , Epilepsia/fisiopatologia , Feminino , Seguimentos , Humanos , Lactente , Levetiracetam , Masculino , Piracetam/efeitos adversos , Piracetam/análogos & derivados , Estudos Prospectivos , Estatísticas não Paramétricas
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