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991.
Gianni Ciofani Giada G. Genchi Ioannis Liakos Valentina Cappello Mauro Gemmi Athanassia Athanassiou Barbara Mazzolai Virgilio Mattoli 《Pharmaceutical research》2013,30(8):2133-2145
Purpose
Oxidative stress has been found to play a key role in several diseases, that range from cancer to neurodegenerative disorders. Besides traditional anti-oxidant agents, in recent years much attention has been focused on nanotechnological solutions, including cerium oxide nanoparticles (nanoceria).Methods
Thanks to its extraordinary catalytic properties, nanoceria mimics the activity of superoxide dismutase and of catalase, therefore acting as a reactive oxygen species (ROS) scavenger in many biological contexts. In this paper, we report on nanoceria interactions with PC12 cell line, that represents a valuable model for many features of central dopaminergic neurons.Results
Nanoceria confirmed a strong anti-ROS action but, most interestingly, also showed beneficial effects on both cell differentiation and dopamine production.Conclusions
Even if deeper examinations will be necessary in order to better clarify the mechanisms at the base of the documented effects, nanoceria demonstrated a significant potential as pharmacological agent in the treatment of neurological disorders. 相似文献992.
Valentina Galbiati Verónica Martínez Sara Bianchi Montserrat Mitjans Emanuela Corsini 《Toxicology in vitro》2013,27(1):103-110
Differentiation between photoallergenic and phototoxic reactions induced by low molecular weight compounds represents a current problem. The use of keratinocytes as a potential tool for the detection of photoallergens as opposed to photoirritants is considered an interesting strategy for developing in vitro methods. We have previously demonstrated the possibility to use the human keratinocyte cell line NCTC2455 and the production of interleukin-18 (IL-18) to screen low molecular weight sensitizers. The purpose of this work was to explore the possibility to use the NCTC2544 assay to identify photoallergens and discriminate from phototoxic chemicals.First, we identified suitable condition of UV-irradiation (3.5 J/cm2) by investigating the effect of UVA irradiation on intracellular IL-18 on untreated or chloropromazine (a representative phototoxic compound)-treated NCTC2544 cells. Then, the effect of UVA-irradiation over NCTC2544 cells treated with increasing concentrations of 15 compounds including photoallergens (benzophenone, 4-ter-butyl-4-methoxy-dibenzoylmethane, 2-ethylexyl-p-methoxycinnamate, ketoprofen, 6-methylcumarin); photoirritant and photoallergen (4-aminobenzoic acid, chlorpromazine, promethazine); photoirritants (acridine, ibuprofen, 8-methoxypsoralen, retinoic acid); and negative compounds (lactic acid, SDS and p-phenilendiamine) was investigated. Twenty-four hours after exposure, cytotoxicity was evaluated by the MTT assay or LDH leakage, while ELISA was used to measure the production of IL-18. At the maximal concentration assayed with non-cytotoxic effects (CV80 under irradiated condition), all tested photoallergens induced a significant and a dose-dependent increase of intracellular IL-18 following UVA irratiation, whereas photoirritants failed. We suggest that this system may be useful for the in vitro evaluation of the photoallergic potential of chemicals. 相似文献
993.
Daniele Caprioli Young T Hong Stephen J Sawiak Valentina Ferrari David J Williamson Bianca Jupp T Adrian Carpenter Franklin I Aigbirhio Barry J Everitt Trevor W Robbins Tim D Fryer Jeffrey W Dalley 《Neuropsychopharmacology》2013,38(8):1460-1471
We have previously shown that impulsivity in rats predicts the emergence of compulsive cocaine seeking and taking, and is coupled to decreased D2/3 receptor availability in the ventral striatum. As withdrawal from cocaine normalises high impulsivity in rats, we investigated, using positron emission tomography (PET), the effects of response-contingent cocaine administration on D2/3 receptor availability in the striatum. Rats were screened for impulsive behavior on the five-choice serial reaction time task. After a baseline PET scan with the D2/3 ligand [18F]fallypride, rats were trained to self-administer cocaine for 15 days under a long-access schedule. As a follow-up, rats were assessed for impulsivity and underwent a second [18F]fallypride PET scan. At baseline, we found that D2/3 receptor availability was significantly lower in the left, but not right, ventral striatum of high-impulsive rats compared with low-impulsive rats. While the number of self-administered cocaine infusions was not different between the two impulsivity groups, impulsivity selectively decreased in high-impulsive rats withdrawn from cocaine. This effect was accompanied by a significant increase in D2/3 receptor availability in the left, but not right, ventral striatum. We further report that D2/3 receptor availability was inversely related to baseline D2/3 receptor availability in the ventral striatum of high-impulsive rats, as well as to the left and right dorsal striatum of both low-impulsive and high-impulsive rats. These findings indicate that the reduction in impulsivity in high-impulsive rats by prior cocaine exposure may be mediated by a selective correction of deficient D2/3 receptor availability in the ventral striatum. A similar baseline-dependent mechanism may account for the therapeutic effects of stimulant drugs in clinical disorders such as ADHD. 相似文献
994.
Angelo Blasio Attilio Iemolo Valentina Sabino Stefania Petrosino Luca Steardo Kenner C Rice Pierangelo Orlando Fabio Arturo Iannotti Vincenzo Di Marzo Eric P Zorrilla Pietro Cottone 《Neuropsychopharmacology》2013,38(12):2498-2507
The anti-obesity medication rimonabant, an antagonist of cannabinoid type-1 (CB1) receptor, was withdrawn from the market because of adverse psychiatric side effects, including a negative affective state. We investigated whether rimonabant precipitates a negative emotional state in rats withdrawn from palatable food cycling. The effects of systemic administration of rimonabant on anxiety-like behavior, food intake, body weight, and adrenocortical activation were assessed in female rats during withdrawal from chronic palatable diet cycling. The levels of the endocannabinoids, anandamide and 2-arachidonoylglycerol (2-AG), and the CB1 receptor mRNA and the protein in the central nucleus of the amygdala (CeA) were also investigated. Finally, the effects of microinfusion of rimonabant in the CeA on anxiety-like behavior, and food intake were assessed. Systemic administration of rimonabant precipitated anxiety-like behavior and anorexia of the regular chow diet in rats withdrawn from palatable diet cycling, independently from the degree of adrenocortical activation. These behavioral observations were accompanied by increased 2-AG, CB1 receptor mRNA, and protein levels selectively in the CeA. Finally, rimonabant, microinfused directly into the CeA, precipitated anxiety-like behavior and anorexia. Our data show that (i) the 2-AG-CB1 receptor system within the CeA is recruited during abstinence from palatable diet cycling as a compensatory mechanism to dampen anxiety, and (ii) rimonabant precipitates a negative emotional state by blocking the beneficial heightened 2-AG-CB1 receptor signaling in this brain area. These findings help elucidate the link between compulsive eating and anxiety, and it will be valuable to develop better pharmacological treatments for eating disorders and obesity. 相似文献
995.
Valentina Sarao Daniele Veritti Erica Maurutto Nicolò Rassu Enrico Borrelli Anat Loewenstein 《Expert opinion on pharmacotherapy》2013,14(14):1551-1563
ABSTRACTIntroduction: Cataracts and diabetes are widespread pathologies that are of growing concern to the global population. In diabetic patients who have had cataract surgery, the worsening of preexisting diabetic macular edema or occurrence of pseudophakic cystoid macular edema are common causes of visual impairment even with the most advanced surgical techniques available today for phacoemulsification.Areas covered: In this review, the authors assess the available literature to evaluate and compare different drugs, with the aim of establishing the best pharmacological strategies for the prevention and treatment of macular edema in diabetic patients undergoing cataract surgery.Expert opinion: Guidelines for the optimal management of diabetic macular edema in conjunction with cataract surgery or treatment of pseudophakic cystoid macular edema in diabetic patients are still lacking. To treat these conditions, clinicians need to understand the pharmacokinetics, posology, and efficacy of available drugs: topical non-steroidal anti-inflammatory drugs (NSAIDs), intravitreal anti-vascular endothelial growth factors (VEGFs), and both topical and intravitreal steroids. Diabetic patients undergoing cataract surgery should receive topical NSAIDs to prevent pseudophakic cystoid macular edema. Intravitreal anti-VEGFs and steroids, in association with cataract surgery, are indicated for patients with preexisting diabetic macular edema or those at high risk of macular edema after surgery. 相似文献
996.
Anna S Tsimokha Valentina A. Kulichkova Elena V. Karpova Julia J. Zaykova Nikolai D Aksenov Anastasia A. Vasilishina Andrei V. Kropotov Alexey Antonov Nikolai A. Barlev 《Oncotarget》2014,5(11):3555-3567
26S proteasomes are known as major non-lysosomal cellular machines for coordinated and specific destruction of ubiquitinylated proteins. The proteolytic activities of proteasomes are controlled by various post-translational modifications in response to environmental cues, including DNA damage. Besides proteolysis, proteasomes also associate with RNA hydrolysis and splicing. Here, we extend the functional diversity of proteasomes by showing that they also dynamically associate with microRNAs (miRNAs) both in the nucleus and cytoplasm of cells. Moreover, DNA damage induced by an anti-cancer drug, doxorubicin, alters the repertoire of proteasome-associated miRNAs, enriching the population of miRNAs that target cell cycle checkpoint regulators and DNA repair proteins. Collectively, these data uncover yet another potential mode of action for proteasomes in the cell via their dynamic association with microRNAs. 相似文献
997.
998.
999.
Ylenia Lombardo Monica Faronato Aleksandra Filipovic Valentina Vircillo Luca Magnani R Charles Coombes 《Breast cancer research : BCR》2014,16(3):R62