DMF (dimethyl fumarate) exerts anti-inflammatory and pro-metabolic effects in a variety of cell types, and a formulation (BG-12) is being evaluated for monotherapy in multiple sclerosis patients. DMF modifies glutathione (GSH) levels that can induce expression of the anti-inflammatory protein HO-1 (haem oxygenase-1). In primary astrocytes and C6 glioma cells, BG-12 dose-dependently suppressed nitrite production induced by either LI [LPS (lipopolysaccharide) at 1 μg/ml plus IFNγ (interferon γ) at 20 units/ml] or a mixture of pro-inflammatory cytokines, with greater efficacy in C6 cells. BG-12 reduced NOS2 (nitric oxide synthase 2) mRNA levels and activation of a NOS2 promoter, reduced nuclear levels of NF-κB (nuclear factor κB) p65 subunit and attenuated loss of IκBα (inhibitory κBα) in both cell types, although with greater effects in astrocytes. In astrocytes, LI decreased mRNA levels for GSHr (GSH reductase) and GCL (c-glutamylcysteine synthetase), and slightly suppressed GSHs (GSH synthetase) mRNAs. Co-treatment with BG-12 prevented those decreased and increased levels above control values. In contrast, LI reduced GSHp (GSH peroxidase) and GCL in C6 cells, and BG-12 had no effect on those levels. BG-12 increased nuclear levels of Nrf2 (nuclear factor-erythroid 2 p45 subunit-related factor 2), an inducer of GSH-related enzymes, in astrocytes but not C6 cells. In astrocytes, GSH was decreased by BG-12 at 2 h and increased at 24 h. Prior depletion of GSH using buthionine-sulfoximine increased the ability of BG-12 to reduce nitrites. In astrocytes, BG-12 increased HO-1 mRNA levels and effects on nitrite levels were blocked by an HO-1 inhibitor. These results demonstrate that BG-12 suppresses inflammatory activation in astrocytes and C6 glioma cells, but with distinct mechanisms, different dependence on GSH and different effects on transcription factor activation.
The neurotransmitter norepinephrine (NE) can inhibit inflammatory gene expression in glial cells; however, the mechanisms involved are not clear. In primary astrocytes, NE dose-dependently increased the expression of inhibitory IB␣ protein accompanied by an increase in steady state levels of IB␣ mRNA. Maximal increases were observed at 30 -60 min for the mRNA and at 4 h for protein, and these effects were mediated by NE binding to -adrenergic receptors. NE activated a 1.3-kilobase IB␣ promoter transfected into astrocytes or C6 glioma cells, and this activation was prevented by a -antagonist and by protein kinase A inhibitors but not by an NFB inhibitor. NE increased IB␣ protein in both the cytosolic and the nuclear fractions, suggesting an increase in nuclear uptake of IB␣. IB␣ was detected in the frontal cortex of normal adult rats, and its levels were reduced if central NE levels were depleted by lesion of the locus ceruleus. The reduction of brain IB␣ levels was paralleled by increased inflammatory responses to lipopolysaccharide. These results demonstrate that IB␣ expression is regulated by NE at both transcriptional and post-transcriptional levels, which could contribute to the observed anti-inflammatory properties of NE in vitro and in vivo.The activation of inflammatory responses in brain is normally under tight regulation that prevents the accumulation of potentially cytotoxic mediators including cytokines and reactive oxygen species (1-3). It has therefore been suggested that intrinsic mechanisms exist that maintain the brain in a refractory state of inflammatory activation. In primary cultures of rat astrocytes, we showed that neurotransmitter norepinephrine (NE) 1 prevents induction of the inducible form of nitric oxide synthase (NOS2) (4, 5) by bacterial endotoxin lipopolysaccharide (LPS) or by a combination of proinflammatory cytokines (interleukin 1, tumor necrosis factor ␣, and interferon ␥). Similarly, others show that NE reduces glial expression of pro-inflammatory cytokines including interleukin 1 and tumor necrosis factor ␣ (6 -9) and of cell adhesion molecules (13). A similar role for NE in regulating inflammatory events in brain is supported by our recent findings that experimental depletion of brain NE levels by chemical lesion of the locus ceruleus (LC) increases the cortical inflammatory responses to injection of aggregated amyloid  (14). The fact that LC neurons are lost in Alzheimer's disease (15) and that levels of  2 -adrenergic receptor (ARs) are reduced in astrocytes in multiple sclerosis patients (16,17) suggests that diminished NE levels or perturbations of the NE-signaling system contribute to the neuroinflammation that occurs in these diseases.The mechanism(s) by which NE reduces inflammatory gene expression is not yet well defined. In astrocytes, we found that NE induced protein binding to a 27-bp region of the rat NOS2 promoter, which is located immediately upstream of a NFB binding site located at bp position Ϫ107 to Ϫ96 (18). This 27-bp region contains several potenti...
The overall response rate (ORR) is a largely adopted outcome measure in early-phase oncology trials. ORR is highly relevant in cancer drug development at the time of deciding whether to move to confirmatory phase 3 trials; moreover, ORR is gaining increasing relevance in fast-track registration procedures. No systematic analysis has been conducted so far to investigate whether a discrepancy exists between ORR assessed by local investigators and those assessed by blinded reviewers in phase 2 oncology trials. In this study, we carried out a search in the clinicaltrials.gov and EudraCT databases, looking at the trials reporting the results of both investigator-assessed and independently-assessed ORR. A discrepancy index was obtained by calculating the ratio of each investigator-assessed ORR on the corresponding independently assessed ORR, so that a discrepancy index >1 indicates that the investigator was "more optimistic," whereas a discrepancy index <1 indicates the opposite. We also analyzed different subgroups (by tumor type, by drug type, by year). Twenty trials met the search criteria; in some cases, >1 comparison was conducted in the trial, so that the total number of comparisons analyzed was 33. The estimated mean discrepancy index was 1.175 (95% confidence interval, 1.083-1.264; n = 33). In conclusion, local investigators significantly overestimate ORR compared to paired blinded reviewers in phase 2 oncology trials. This may represent a risk in drug development, when deciding whether to move to confirmatory, more expensive phase 3 trials. Blinded independent central review should be used in ORR assessment if a more conservative estimate of treatment efficacy is required, as in the case of fast-track drug developments leading to accelerated approvals of cancer therapies.
The aim of personalized medicine is to detach from a “one-size fits all approach” and improve patient health by individualization to achieve the best outcomes in disease prevention, diagnosis and treatment. Technological advances in sequencing, improved knowledge of omics, integration with bioinformatics and new in vitro testing formats, have enabled personalized medicine to become a reality. Individual variation in response to environmental factors can affect susceptibility to disease and response to treatments. Space travel exposes humans to environmental stressors that lead to physiological adaptations, from altered cell behavior to abnormal tissue responses, including immune system impairment. In the context of human space flight research, human health studies have shown a significant inter-individual variability in response to space analogue conditions. A substantial degree of variability has been noticed in response to medications (from both an efficacy and toxicity perspective) as well as in susceptibility to damage from radiation exposure and in physiological changes such as loss of bone mineral density and muscle mass in response to deconditioning. At present, personalized medicine for astronauts is limited. With the advent of longer duration missions beyond low Earth orbit, it is imperative that space agencies adopt a personalized strategy for each astronaut, starting from pre-emptive personalized pre-clinical approaches through to individualized countermeasures to minimize harmful physiological changes and find targeted treatment for disease. Advances in space medicine can also be translated to terrestrial applications, and vice versa. This review places the astronaut at the center of personalized medicine, will appraise existing evidence and future preclinical tools as well as clinical, ethical and legal considerations for future space travel.
Glioma associated microglia/macrophages (GAMs) constitute the largest proportion of glioma infiltrating cells, particularly in high grade tumors (i.e., glioblastoma). Once inside the tumors, GAMs usually acquire a specific phenotype of activation that favors tumor growth, angiogenesis and promotes the invasion of normal brain parenchyma. Therefore, treatments that limit or prevent GAMs' recruitment at the tumor site or modulate their immune activation promoting antitumor activities are expected to exert beneficial effects in glioblastoma. In the present paper, we aim at the revision of pharmacological strategies that interfere with GAMs' function and are currently proposed as an alternative/additional option to current approved cytotoxic regimens.
Preliminary evidence in an animal model, that is, primary cultures of rat microglia cells, suggested that some antiretroviral drugs (ARVs), namely darunavir, atazanavir, efavirenz, and nevirapine, increase NO production through a mechanism involving the inhibition of arginase (ARG) activity. This study was conceived to investigate the effects of ARVs on ARG activity in a human experimental model. We compared CHME-5 human microglial immortalized cells under basal conditions with cells exposed to either IL-4, a mix of inflammatory cytokines, or both stimuli given together. We also tested the effects of ARVs on CHME-5 cell lysates after exposure to the above stimuli. Moreover, the interaction between the ARVs and ARG was investigated via computational chemistry. We found that ARVs consistently inhibit ARG activity both in intact and lysed cells. In docking studies, darunavir and atazanavir showed similar scores compared with both L-arginine and the ARG antagonist nor-NOHA. Efavirenz and nevirapine, which are less potent in inhibiting ARG in the biochemical assay, also had lower scores. In conclusion, the present findings in a human model support the notion that ARG pathway can present a new, additional molecular target for different ARVs in HIV treatments.
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