ABSTRACT
Oxygen is a powerful trigger for cellular reactions and is used in many pathologies, including oxidative stress. However, the effects of oxygen over time and at different partial pressures remain poorly understood. In this study, the metabolic responses of normobaric oxygen intake for 1 h to mild (30%) and high (100%) inspired fractions were investigated. Fourteen healthy non-smoking subjects (7 males and 7 females; age: 29.9 ± 11.1 years, height: 168.2 ± 9.37 cm; weight: 64.4 ± 12.3 kg; BMI: 22.7 ± 4.1) were randomly assigned in the two groups. Blood samples were taken before the intake at 30 min, 2 h, 8 h, 24 h, and 48 h after the single oxygen exposure. The level of oxidation was evaluated by the rate of reactive oxygen species (ROS) and the levels of isoprostane. Antioxidant reactions were observed by total antioxidant capacity (TAC), superoxide dismutase (SOD), and catalase (CAT). The inflammatory response was measured using interleukin-6 (IL-6), neopterin, creatinine, and urates. Oxidation markers increased from 30 min on to reach a peak at 8 h. From 8 h post intake, the markers of inflammation took over, and more significantly with 100% than with 30%. This study suggests a biphasic response over time characterized by an initial "permissive oxidation" followed by increased inflammation. The antioxidant protection system seems not to be the leading actor in the first place. The kinetics of enzymatic reactions need to be better studied to establish therapeutic, training, or rehabilitation protocols aiming at a more targeted use of oxygen.
Subject(s)
Hyperoxia , Female , Humans , Male , Antioxidants/metabolism , Hyperoxia/metabolism , Oxidative Stress , Oxygen/pharmacology , Reactive Oxygen Species/metabolism , Superoxide Dismutase/metabolism , Adolescent , Young Adult , AdultABSTRACT
Huntington's disease (HD) is a progressive neurodegenerative genetic disorder which leads to motor, cognitive and psychiatric disturbances. The primary neuropathological hallmark is atrophy of the striatum. Cannabinoid CB1 receptors (CB1Rs) are particularly enriched in the striatum and previous works indicate their early loss of expression in HD, even before symptom occurrence. However, pathophysiological significance of this loss of expression remains unclear. In addition, whether specific modulation of CB1R is able to mitigate striatal neuron fate in HD remains currently controversial. In order to gain further insights on the potential role of CB1R in HD physiopathology, we evaluated the pathophysiological consequences of a genetic deletion of CB1R in the N171-82Q transgenic model and following 3-nitropropionic (3NP) intoxication. Taken together our data demonstrate that CB1R knockout (1) worsens motor performances in N171-82Q mice and (2) increases mouse susceptibility to 3NP. These results suggest that functional changes in CB1R may contribute to the physiopathological development of HD.
Subject(s)
Corpus Striatum/pathology , Huntington Disease/genetics , Neurons/pathology , Receptor, Cannabinoid, CB1/genetics , Analysis of Variance , Animals , Corpus Striatum/drug effects , Corpus Striatum/metabolism , Corpus Striatum/physiopathology , Disease Models, Animal , Disease Progression , Female , Huntington Disease/metabolism , Huntington Disease/pathology , Huntington Disease/physiopathology , Male , Mice , Mice, Knockout , Motor Activity/physiology , Neurons/drug effects , Neurons/metabolism , Nitro Compounds/pharmacology , Phenotype , Propionates/pharmacology , Receptor, Cannabinoid, CB1/metabolism , Rotarod Performance TestABSTRACT
Vaccination of dendritic cells (DC) combined with GM-CSF secreting tumor cells has shown good therapeutic efficacy in several tumor models. Nevertheless, the engineering of GM-CSF secreting tumor cell line could represent a tedious step limiting its application for treatment in patients. We therefore developed in rats, an "all in vivo" strategy of combined vaccination using an in vivo local irradiation of the tumor as a source of tumor antigens for DC vaccines and an exogenous source of GM-CSF. We report here that supplying recombinant mGM-CSF by local injections or surgical implantation of osmotic pumps did not allow reproducing the therapeutic efficacy observed with in vitro prepared combined vaccines. To bypass this limitation possibly due to the short half-life of recombinant GM-CSF, we have generated adeno-associated virus coding for mGM-CSF and tested their efficacy to transduce tumor cells in vitro and in vivo. The in vivo vaccines combining local irradiation and AAV2/1-mGM-CSF vectors showed high therapeutic efficacy allowing to cure 60% of the rats with pre-implanted tumors, as previously observed with in vitro prepared vaccines. Same efficacy has been observed with a second generation of vaccines combining DC, local tumor irradiation, and the controlled supply of recombinant mGM-CSF in poloxamer 407, a biocompatible thermoreversible hydrogel. By generating a successful "all in vivo" vaccination protocol combining tumor radiotherapy with DC vaccines and a straightforward supply of GM-CSF, we have developed a therapeutic strategy easily translatable to clinic that could become accessible to a much bigger number of cancer patients.
Subject(s)
Antineoplastic Agents/therapeutic use , Cancer Vaccines/therapeutic use , Dendritic Cells/immunology , Granulocyte-Macrophage Colony-Stimulating Factor/therapeutic use , Neoplasms, Experimental/radiotherapy , Neoplasms, Experimental/therapy , Animals , Antineoplastic Agents/administration & dosage , Apoptosis/drug effects , Apoptosis/immunology , Cancer Vaccines/immunology , Cell Line, Tumor , Combined Modality Therapy , Dendritic Cells/transplantation , Granulocyte-Macrophage Colony-Stimulating Factor/administration & dosage , Granulocyte-Macrophage Colony-Stimulating Factor/immunology , Injections, Intralesional , Male , Neoplasms, Experimental/drug therapy , Neoplasms, Experimental/immunology , Rats , Rats, Inbred F344 , Recombinant Proteins/administration & dosage , Recombinant Proteins/immunology , Recombinant Proteins/therapeutic use , Xenograft Model Antitumor AssaysABSTRACT
Huntington's disease (HD) is a progressive neurodegenerative genetic disorder that leads to motor, cognitive, and psychiatric disturbances. The primary neuropathological hallmark is atrophy of the striatum. HD preferentially affects efferent striato-pallidal neurons that express enkephalin as well as dopamine D2 and A(2A) adenosine receptors (A(2A)Rs). Expression and function of A(2A)Rs are altered in HD but, despite being an important modulator of the striato-pallidal function, the subsequent pathophysiological consequence of such changes remains unclear. Whether blockade of A(2A)Rs is of therapeutic interest in HD remains ill-defined. In the present work, we aimed to determine the pathophysiological consequences of genetic deletion of A(2A)Rs in HD by crossing A(2A)R knockout mice with the N171-82Q HD transgenic model. Our data demonstrate that knockout of A(2A)Rs moderately but significantly worsens motor performances and survival of N171-82Q mice and leads to a decrease in striatal enkephalin expression. These results support that early and chronic blockade of A(2A)Rs might not be beneficial in HD.
Subject(s)
Huntington Disease/genetics , Huntington Disease/metabolism , Movement Disorders/genetics , Movement Disorders/metabolism , Receptor, Adenosine A2A/deficiency , Receptor, Adenosine A2A/genetics , Animals , Enkephalins/antagonists & inhibitors , Enkephalins/metabolism , Female , Huntingtin Protein , Huntington Disease/pathology , Male , Mice , Mice, Inbred C3H , Mice, Inbred C57BL , Mice, Knockout , Mice, Transgenic , Movement Disorders/pathology , Nerve Tissue Proteins/deficiency , Nerve Tissue Proteins/genetics , Neurons/metabolism , Neurons/pathology , Nuclear Proteins/deficiency , Nuclear Proteins/genetics , Survival RateABSTRACT
According to the recent controversy regarding the effects of minocycline in the R6/2 transgenic model of Huntington's disease (HD), this tetracycline has been re-evaluated in another model, the N171-82Q strain. Ten miligrams per kilogram minocycline was given daily from the age of 2 mo, corresponding to an early symptomatic stage. We did not observe improvement in survival, weight loss, or motor function in treated transgenic mice. In addition, minocycline failed to mitigate the ventricle enlargement as well as the striatal and cortical atrophies induced by the transgene. Using high-performance liquid chromatography, it was observed that minocycline was similarly present in the plasma and the brain of both wild-type and N171-82Q mice following 14 daily injections. Using Western blot, we show that the increased expression of procaspase-1 induced by the transgene in the cortex was significantly reduced by the antibiotic. Combining together these data support that despite minocycline crosses blood-brain barrier in N171-82Q mice and displays an expected effect on procaspase-1 expression, it does not provide protection in this HD model. These in vivo results are in accordance with in vitro data, since minocycline failed to protect against mutated Huntingtin in an inducible PC12-clone expressing exon1 of mutated Huntingtin103Q. Altogether, the present data does not support minocycline as a beneficial drug for HD.
Subject(s)
Anti-Bacterial Agents/therapeutic use , Huntington Disease/metabolism , Huntington Disease/prevention & control , Minocycline/therapeutic use , Animals , Anti-Bacterial Agents/pharmacology , Brain/metabolism , Caspase 1/biosynthesis , Cell Line , Huntingtin Protein , Huntington Disease/physiopathology , Mice , Mice, Transgenic , Minocycline/pharmacology , Mutation , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , PC12 Cells , RatsABSTRACT
We have evaluated the neuroprotective effects of citicoline in relevant phenotypic models of Huntington's disease induced by either the mitochondrial inhibitor 3-nitropropionic acid or the N-methyl-D-aspartate agonist quinolinic acid, which, respectively, reproduce the metabolic defect or the excitotoxicity seen in the disease. We found that citicoline failed to reverse behavioural and histological alterations induced by both neurotoxins. In addition, citicoline did not reduce PC12 cell death induced by the expression of an N-terminal fragment of mutated Huntingtin. Altogether, our results suggest that citicoline is not a potential therapeutic agent for the treatment of Huntington's disease.
